TY - CHAP
TI - Optical Packet Switching (OPS)
AU - Rouskas, G.N.
AU - Xu, L.
T2 - Optical Networks
A2 - Sivalingam, Krishna
A2 - Subramanian, Suresh
PY - 2006/6/15/
DO - 10.1007/0-387-29188-1_17
SP - 797–843
PB - Kluwer Academic Publishers
SN - 0387290559
UR - http://dx.doi.org/10.1007/0-387-29188-1_17
ER -
TY - JOUR
TI - Dynamic Wavelength Sharing Policies for Absolute QoS in OBS Networks
AU - Yang, Li
AU - Rouskas, George N.
AU - IEEE
T2 - Globecom 2006 - 2006 Ieee Global Telecommunications Conference
DA - 2006///
PY - 2006///
ER -
TY - JOUR
TI - Adaptive path selection in OBS networks
AU - Yang, Li
AU - Rouskas, George N.
T2 - Journal of Lightwave Technology
AB - In this paper, the authors investigate the concept of adaptive path selection in optical burst-switched networks and its potential to reducing the overall burst drop probability. Specifically, the authors assume that each source maintains a (short) list of alternate paths to each destination and uses information regarding the recent congestion status of the network links to rank the paths; it then transmits bursts along the least congested path. The authors present a suite of path selection strategies, each utilizing a different type of information regarding the link congestion status, and evaluate them using simulation. The results demonstrate that, in general, adaptive path selection outperforms shortest path routing, and, depending on the path strategy involved, the network topology, and the traffic pattern, this improvement can be significant. A new framework for the development of hybrid (or meta) path selection strategies, which make routing decisions based on a weighted combination of the decisions taken by several independent path selection strategies, has been presented. This paper presents two instances of such hybrid strategies, i.e., 1) one that assigns static weights and 2) one that dynamically adjusts the weights based on feedback from the network; it has been shown that these strategies can further improve the overall burst drop probability in the network.
DA - 2006///
PY - 2006///
DO - 10.1109/JLT.2006.878087
VL - 24
IS - 8
SP - 3002-3011
ER -
TY - JOUR
TI - A framework for absolute QoS guarantees in optical burst switched networks
AU - Yang, Li
AU - Rouskas, George N.
AU - IEEE
T2 - 2006 3rd International Conference on Broadband Communications, Networks and Systems, Vols 1-3
DA - 2006///
PY - 2006///
SP - 1-10
ER -
TY - CONF
TI - Integrating Production Planning and Safety Stock Determination
AU - Uzsoy, R.
AU - Ravindran, A.
T2 - INFORMS National Meeting
C2 - 2006/11//
CY - Pittsburgh, PA
DA - 2006/11//
PY - 2006/11//
ER -
TY - CONF
TI - Integrated Production Planning and Pricing with Congestion-Prone Production Resources
AU - Upasani, A.
AU - Uzsoy, R.
T2 - INFORMS National Meeting
C2 - 2006/11//
CY - Pittsburgh, PA
DA - 2006/11//
PY - 2006/11//
ER -
TY - CONF
TI - Multiproduct Dynamic Lot Sizing with Work in Process and Congestion
AU - Hwang, S.
AU - Uzsoy, R.
T2 - INFORMS National Meeting
C2 - 2006/11//
CY - Pittsburgh, PA
DA - 2006/11//
PY - 2006/11//
ER -
TY - CONF
TI - A Common Modeling Framework for Transportation and Production Planning Problems with Congestion Phenomena
AU - Kalafatas, G.
AU - Peeta, S.
AU - Uzsoy, R.
T2 - INFORMS National Meeting
C2 - 2006/11//
CY - Pittsburgh, PA
DA - 2006/11//
PY - 2006/11//
ER -
TY - CONF
TI - A Genetic Algorithm for a Single Product Network Design Model with Lead Time and Safety Stock Considerations
AU - Sourirajan, K.
AU - Ozsen, L.
AU - Uzsoy, R.
T2 - INFORMS National Meeting
C2 - 2006/11//
CY - Pittsburgh, PA
DA - 2006/11//
PY - 2006/11//
ER -
TY - CONF
TI - A Multi-Product Break-Bulk Network Design Model with Lead Time and Safety Stock Considerations
AU - Sourirajan, K.
AU - Ozsen, L.
AU - Uzsoy, R.
T2 - INFORMS National Meeting
C2 - 2006/11//
CY - Pittsburgh, PA
DA - 2006/11//
PY - 2006/11//
ER -
TY - SOUND
TI - From Engineering the System to Engineering Information
AU - Deshmukh, A.
AU - Uzsoy, R.
DA - 2006/2//
PY - 2006/2//
ER -
TY - CONF
TI - Heuristics for Scheduling a Single Machine with Family Dependent Setup Times
AU - Uzsoy, R.
AU - Velasquez, J.D.
T2 - INFORMS National Meeting
C2 - 2006/11//
CY - Pittsburgh, PA
DA - 2006/11//
PY - 2006/11//
ER -
TY - CONF
TI - Scheduling Engineering and Production Lots in Wafer Fabrication
AU - Crist, K.
AU - Uzsoy, R.
T2 - INFORMS National Meeting
C2 - 2006/11//
CY - Pittsburgh, PA
DA - 2006/11//
PY - 2006/11//
ER -
TY - CONF
TI - Juggling Tasks: Mine, Yours and Ours...
AU - Mendez, L.I.
AU - Uzsoy, R.
T2 - INFORMS National Meeting
C2 - 2006/11//
CY - Pittsburgh, PA
DA - 2006/11//
PY - 2006/11//
ER -
TY -
ER -
TY - JOUR
TI - A Problem Reduction Approach for Scheduling Semiconductor Wafer Fabrication Facilities
AU - Upasani, A.A.
AU - Uzsoy, R.
AU - Sourirajan, K.
T2 - IEEE Transactions on Semiconductor Manufacturing
AB - Most scheduling procedures used in industry are based on the dispatching paradigm, where decisions are made based on the jobs available at the time the machine becomes free. While optimization-based scheduling procedures have repeatedly been shown to yield significantly better schedules under ideal circumstances, their practical implementation is hampered by high computational requirements. We present a problem reduction procedure that allows a workcenter-based global scheduling heuristic to be implemented in very low CPU times. The procedure partitions the workcenters in a fab into heavily loaded and lightly loaded classes and solves the global scheduling problem only for the heavily loaded workcenters. The proposed technique is tested on instances drawn from an International SEMATECH wafer fab model. The proposed problem reduction approach yields superior results with modest computational effort, enabling the practical use of the decomposition heuristic.
DA - 2006/5//
PY - 2006/5//
DO - 10.1109/tsm.2006.873510
VL - 19
IS - 2
SP - 216-225
J2 - IEEE Trans. Semicond. Manufact.
LA - en
OP -
SN - 0894-6507
UR - http://dx.doi.org/10.1109/tsm.2006.873510
DB - Crossref
KW - empirical testing
KW - heuristic decomposition
KW - scheduling
ER -
TY - JOUR
TI - Tractable Nonlinear Production Planning Models for Semiconductor Wafer Fabrication Facilities
AU - Asmundsson, J.
AU - Rardin, R.L.
AU - Uzsoy, R.
T2 - IEEE Transactions on Semiconductor Manufacturing
AB - We describe a simulation study of a production planning model for multistage production inventory systems that reflects the nonlinear relationship between resource utilization and lead time. The model is based on the use of clearing functions that capture the nonlinear relationship between workload and throughput. We show how these clearing functions can be estimated from empirical data using a simulation model as a surrogate for observation of the production system under study. We then examine the sensitivity of the estimated clearing function to different dispatching algorithms, different demand patterns, and production planning techniques. Computational experiments based on a scaled-down model of a semiconductor wafer fabrication facility illustrate the potential benefits of the clearing function model relative to conventional linear programming models.
DA - 2006/2//
PY - 2006/2//
DO - 10.1109/tsm.2005.863214
VL - 19
IS - 1
SP - 95-111
J2 - IEEE Trans. Semicond. Manufact.
LA - en
OP -
SN - 0894-6507
UR - http://dx.doi.org/10.1109/tsm.2005.863214
DB - Crossref
KW - cycle times
KW - linear programming
KW - production planning
KW - wafer fabrication
ER -
TY - JOUR
TI - Low-level exertions of the neck musculature: A study of research methods
AU - Joines, Sharon M.B.
AU - Sommerich, Carolyn M.
AU - Mirka, Gary A.
AU - Wilson, James R.
AU - Moon, Samuel D.
T2 - Journal of Electromyography and Kinesiology
AB - Musculoskeletal neck discomfort is prevalent in many occupations and has been the focus of much research employing surface electromyography (sEMG). Significant differences in experimental methods among researchers make comparisons across studies difficult. The goal of the current research was to use empirical methods to answer specific methodological questions concerning use of sEMG in evaluation of the neck extensor system. This was accomplished in two studies. In Experiment 1, ultrasound technology was used to: (a) determine accessibility of m. splenius and semispinalis capitis with surface electrodes, (b) identify appropriate electrode locations for these muscles/muscle groups, and (c) illustrate potential benefits of using ultrasound in locating muscles/placing electrodes. Experiment 2 sought to assess effects of posture when normalizing sEMG data. Results from Experiment 1 showed no direct access to semispinalis capitis for surface electrodes; their activity can only be sampled as part of a group of muscles. In most subjects, m. splenius was found to be accessible to surface electrodes. Electrode placement recommendations are provided. Results of Experiment 2 showed significant differences in normalized EMG data between a posture-specific technique and a reference posture technique. Posture-specific normalization is recommended for accurately assessing the relative intensity of contractions of these muscles.
DA - 2006/10//
PY - 2006/10//
DO - 10.1016/j.jelekin.2005.09.007
VL - 16
IS - 5
SP - 485-497
J2 - Journal of Electromyography and Kinesiology
LA - en
OP -
SN - 1050-6411
UR - http://dx.doi.org/10.1016/j.jelekin.2005.09.007
DB - Crossref
KW - electrode location
KW - normalization method
KW - muscle access
KW - neck muscles
ER -
TY - CONF
TI - Computationally Efficient Models of Urban and Natural Terrain by Non-iterative Domain Decomposition for L1 Smoothing Splines
AU - Fang, S.
AU - Lin, Y.-M.
AU - Zhang, Y.
AU - Lavery, J. E.
T2 - 25th Army Science Conference
C2 - 2006/12//
C3 - Proceedings of the 25th Army Science Conference
DA - 2006/12//
PY - 2006/12//
ER -
TY - JOUR
TI - Cubic L1 Splines on Triangulated Irregular Networks
AU - Zhang, W.
AU - Fang, S.
AU - Wang, Y.
AU - Lavery, J.E.
T2 - Pacific Journal of Optimization
DA - 2006///
PY - 2006///
VL - 2
IS - 2
SP - 289–317
ER -
TY - JOUR
TI - Capacity Allocation and Inventory Policy in a Distribution System
AU - Dai, Yue
AU - Chao, Xiuli
AU - Fang, Shu Cherng
AU - Nuttle, Henry L. W.
T2 - Asia-Pacific Journal of Operational Research
AB - We consider a single-period distribution system with one supplier and two retailers. The supplier may have infinite or finite capacity. The demand at each retailer is random. When a stockout occurs at one retailer the customer may go to the other retailer. We study both the decentralized and centralized inventory control problems. For the decentralized problem we show that a unique Nash equilibrium exists when the capacity at the supplier is infinite. However, when the capacity is finite, only under certain conditions does the Nash equilibrium exist. For centralized inventory control we obtain the optimal allocation that maximizes the expected profit of the entire supply chain. For the case of decentralized controls we also design channel coordination mechanisms, i.e., a decentralized cost structure resulting in a Nash equilibrium with chain-wide profits equal to those achieved under a fully centralized system. We compare the performance of two retailers in the decentralized and centralized controls and analyze the impact of channel coordination on the whole supply chain.
DA - 2006/12//
PY - 2006/12//
DO - 10.1142/s0217595906001054
VL - 23
IS - 04
SP - 543–571
SN - 0217-5959 1793-7019
UR - http://dx.doi.org/10.1142/s0217595906001054
KW - game theory
KW - supply chain management
KW - channel coordination
KW - capacity allocation problem
ER -
TY - JOUR
TI - Efficient numerical methods for the 2D nonlinear Poisson–Boltzmann equation modeling charged spheres
AU - Li, Zhilin
AU - Qiao, Zhong-hua
AU - Tang, Tao
T2 - Journal of Computational Mathematics
DA - 2006///
PY - 2006///
VL - 24
IS - 3
SP - 252–264
ER -
TY - CONF
TI - Active Incipient Failure Detection: A Nonlinear Case Study
AU - Drake, K.J.
AU - Campbell, S.L.
AU - Andjelkovic, I.
AU - Sweetingham, K.
T2 - 4th International Conference on Computing, Communications and Control Technologies: CCCT '06
C2 - 2006///
C3 - Proceedings of the 4th International Conference on Computing, Communications and Control Technologies: CCCT '06
CY - Orlando, FL
DA - 2006///
PY - 2006/7/20/
ER -
TY - MGZN
TI - New ideas for SIAM conferences from Europe
AU - Ipsen, I.C.F.
T2 - SIAM News
DA - 2006/12//
PY - 2006/12//
VL - 39
SP - 5
M1 - 10
ER -
TY - JOUR
TI - Towards supply chain collaboration: An operations audit of VMI initiatives in the electronics industry
AU - Blackhurst, J.
AU - Craighead, C.W.
AU - Handfield, R.B.
T2 - International Journal of Integrated Supply Management
AB - Recently, there has been an increased focus on supply chain collaboration efforts such as Vendor-Managed Inventory (VMI). Often, supply chain partners have experienced gaps between desired and actual performance in working towards a successful collaborative relationship. In this research, we analysed two VMI initiatives that have not yet produced the level of performance desired by the supply chain partners involved. In each case, an operations audit was performed to determine where characteristic and performance gaps existed. The output of this research effort is inherent in the operations audit process employed, the VMI initiative gaps discovered during the process as well as the steps that could be undertaken to minimise or eliminate these gaps. The paper culminates in a framework that describes the operations audit in terms of an iterative, collaboration evaluation process. The framework and process can serve as valuable mechanisms for understanding the evolution towards collaborative supply chain relationships.
DA - 2006///
PY - 2006///
DO - 10.1504/IJISM.2006.008340
VL - 2
IS - 1-2
SP - 91-105
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33644509533&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Managing conflict of interest issues in purchasing
AU - Handfield, R.B.
AU - Baumer, D.L.
T2 - Journal of Supply Chain Management
AB - SUMMARY
One of the most important elements of ethical purchasing behavior is conflict of interest. In response to the heightened regulatory environment, many organizations have initiated reviews of their conflict of interest policies and ethical codes of behavior in supply management. The goal of the current exploratory study is to determine the most common approaches used to promote compliance with ethical codes of conduct (specifically conflict of interest policies) in supply management. Questionnaires were administered to eight “typical” Fortune 500 companies. Current conflicts of interest policies were identified, in addition to spotlighting common approaches to enforcing ethical behavior, including multiple communication and reporting channels, formal procedures, effective sanctions against violators and regular training of employees in ethical policies. Survey results were used to generate a scoring system that compares the overall level of ethics management maturity based on profiles of the companies studied in the research.
DA - 2006///
PY - 2006///
DO - 10.1111/j.1745-493X.2006.00016.x
VL - 42
IS - 3
SP - 41-50
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33745835070&partnerID=MN8TOARS
ER -
TY - CONF
TI - Dynamic Multidrug Therapies for HIV: Feedback and Structured Treatment Interruption Control Approaches
AU - Tran, H.
AU - Banks, H.T.
AU - David, John
AU - Toivanen, J.A.
AU - Kwon, Hae-Dae
T2 - 17th International Symposium on Mathematical Theory of Networks and Systems
C2 - 2006///
C3 - MTNS 2006 : proceedings of the 17th international symposium on mathematical theory of networks and systems, Kyoto, Japan, 24-28.07.2006.
CY - Kyoto International Conference Hall, Kyoto, Japan
DA - 2006///
PY - 2006/7/24/
PB - Kyoto University
ER -
TY - CONF
TI - Experimenting with Real-Time ATIS: Stepping Forward fromADVANCE
AU - Demers, Alixandra
AU - List, George F.
AU - Wojtowicz, Jeffrey
AU - Kornhauser, Alain
AU - Wallace, Al
AU - Lee, Earl E.
AU - Salasznyk, Paul
T2 - Ninth International Conference on Applications of Advanced Technology in Transportation (AATT)
AB - In the early 1990’s an in-vehicle navigation and route guidance project called ADVANCE was conducted in the northeastern suburbs of Chicago. It proved that travel time data could be updated on in-vehicle devices (albeit not in real-time) to assist drivers in choosing faster routes to their destinations. This past spring, about a decade later, a more progressive but similar 3-moonth field experiment was conducted in upstate New York. Nearly 200 participants used state-of-the-art, in-vehicle navigation and route guidance technology in conjunction with GPS tracking and broadband wireless to share travel time data and pick the shortest paths through a congested network. The route guidance devices observed travel times, uploaded them to a central server that updated a travel time database, and then downloaded every minute to each of the probe vehicles to ensure the latest travel time information was being used while enroute. The experiment resulted in a total of 4,111,210 latitude-longitude position/speed/time points. The largest number of location points per user was 98,018 while the smallest was 117; the average per user was just over 26,000 location points, or 325.5 points per trip. There were 12,629 probe trips for a traveled distance of 147,316 miles over a duration of 3,945.8 hours. This paper presents a discussion of the Capital District ATIS project including the parallels and differences with the ADVANCE effort. Areas covered are: travel time data, project background, description of the study data, participant statistics, experimental design, sample results, and a summary with future research directions.
C2 - 2006/8/4/
C3 - Applications of Advanced Technology in Transportation
DA - 2006/8/4/
DO - 10.1061/40799(213)51
PB - American Society of Civil Engineers
SN - 9780784407998
UR - http://dx.doi.org/10.1061/40799(213)51
DB - Crossref
ER -
TY - CONF
TI - Strategic safety stock placement in production networks with supply risk
AU - Warsing, D.P.
AU - Helmer, E.A.
AU - Blackhurst, J.V.
C2 - 2006///
C3 - 2006 IIE Annual Conference and Exhibition
DA - 2006///
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-36448975542&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Logistics planning under uncertainty for disposition of radioactive wastes
AU - List, George F.
AU - Wood, Bryan
AU - Turnquist, Mark A.
AU - Nozick, Linda K.
AU - Jones, Dean A.
AU - Lawton, Craig R.
T2 - Computers & Operations Research
AB - The US Department of Energy (DOE) faces an enormous environmental remediation challenge involving highly radioactive wastes at former weapons production facilities. The purpose of this analysis is to focus on equipment acquisition and fleet sizing issues related to transportation of wastes from remediation sites to disposal sites. Planning for the transportation of these wastes must be done with recognition of important uncertainties related to overall quantities of waste to be moved, the rate at which the wastes will be prepared for transport, and the certification of suitable transportation containers for use in the effort. However, deadlines for completion of the effort have already been set by the political process, without much regard for these uncertainties. To address this fleet sizing problem, we have created a robust optimization model that focuses on equipment investment decisions. Through this robust optimization, we illustrate how modeling can be used to explore the effects of uncertainty on the equipment acquisition strategy. The disposition of radioactive wastes from DOE sites is an important illustration of a category of problems where equipment investments must be made under conditions of considerable uncertainty. The methodology illustrated in this paper can be applied to this general class of problems.
DA - 2006/3//
PY - 2006/3//
DO - 10.1016/j.cor.2004.07.017
VL - 33
IS - 3
SP - 701-723
J2 - Computers & Operations Research
LA - en
OP -
SN - 0305-0548
UR - http://dx.doi.org/10.1016/j.cor.2004.07.017
DB - Crossref
ER -
TY - CONF
TI - A modified ALA procedure for logistic network designs with scale economies
AU - Bucci, M.J.
AU - Kay, M.G.
C2 - 2006///
C3 - 2006 IIE Annual Conference and Exhibition
DA - 2006///
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84858473880&partnerID=MN8TOARS
ER -
TY - CONF
TI - Supply chain multi-objective simulation optimization
AU - Joines, J.A.
AU - Thoney, K.A.
AU - King, R.E.
AU - Kay, M.G.
C2 - 2006///
C3 - 4th International Industrial Simulation Conference 2006, ISC 2006
DA - 2006///
SP - 377-383
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84898422528&partnerID=MN8TOARS
ER -
TY - RPRT
TI - All-Integer Dual Simplex for Binate Cover Problems (Draft)
AU - Stallmann, M.
DA - 2006///
PY - 2006///
DO -
ER -
TY - JOUR
TI - Rapid Modeling and Discovery of Priority Dispatching Rules: An Autonomous Learning Approach
AU - Geiger, Christopher D.
AU - Uzsoy, Reha
AU - Aytuğ, Haldun
T2 - Journal of Scheduling
DA - 2006/2//
PY - 2006/2//
DO - 10.1007/s10951-006-5591-8
VL - 9
IS - 1
SP - 7-34
J2 - J Sched
LA - en
OP -
SN - 1094-6136 1099-1425
UR - http://dx.doi.org/10.1007/s10951-006-5591-8
DB - Crossref
KW - priority dispatching rules
KW - single machine
KW - rule discovery
KW - genetic programming
ER -
TY - CHAP
TI - Locally Invertible Multivariate Polynomial Matrices
AU - Lobo, Ruben G.
AU - Bitzer, Donald L.
AU - Vouk, Mladen A.
T2 - Coding and Cryptography
PY - 2006///
DO - 10.1007/11779360_33
SP - 427-441
OP -
PB - Springer Berlin Heidelberg
SN - 9783540354819 9783540354826
UR - http://dx.doi.org/10.1007/11779360_33
DB - Crossref
ER -
TY - CONF
TI - Applications of Robust Failure Detection Algorithms to Power Systems
AU - Drake, K.J.
AU - Campbell, S.L.
AU - Andjelkovic, I.V.
AU - Hannas, B.L.
AU - Sweetingham, K.A.
T2 - 13th International Conference on, Intelligent Systems Application to Power Systems
AB - As modelling and simulation become increasingly popular in the design process and as an alternative to expensive testing, fault detection methods based on model identification algorithms become more reliable as well as less expensive and easier to implement. In this paper we discuss the application of two active fault detection algorithms based on model identification to power systems. The algorithms are similar in theory though differ in implementation. The first is a direct optimization approach that handles more general systems and more varied constraints. It requires more sophisticated software but it's easily adapted to more than two models. The second algorithm is a constrained control approach that can be implemented on common math software, such as Matlab or Scilab, and handles model uncertainty. In both cases, the algorithms are free of false alarms depending upon the quality of the models used
C2 - 2006/3/21/
C3 - Proceedings of the 13th International Conference on, Intelligent Systems Application to Power Systems
DA - 2006/3/21/
DO - 10.1109/isap.2005.1599275
PB - IEEE
SN - 1599751747
UR - http://dx.doi.org/10.1109/isap.2005.1599275
DB - Crossref
ER -
TY - CONF
TI - Order of Convergence in the Direct Transcription Solution of Optimal Control Problems
AU - Engelsone, A.
AU - Campbell, S.L.
AU - Betts, J.T.
T2 - 44th IEEE Conference on Decision and Control
AB - In the direct transcription approach to the numerical solution of optimal control problems, the optimal control problem is discretized and the resulting nonlinear programming problem is solved numerically. There has been considerable study over the last 10 years on order of convergence of cost, state, multipliers, and control. This paper discusses these questions, and the highly technical results in the literature, in the context of their implications for industrial grade optimal control packages.
C2 - 2006/10/4/
C3 - Proceedings of the 44th IEEE Conference on Decision and Control
DA - 2006/10/4/
DO - 10.1109/cdc.2005.1582741
PB - IEEE
SN - 0780395670
UR - http://dx.doi.org/10.1109/cdc.2005.1582741
DB - Crossref
ER -
TY - JOUR
TI - Problems and techniques: Introduction
AU - Ipsen, I.C.F.
T2 - SIAM Review
DA - 2006///
PY - 2006///
VL - 48
IS - 2
SP - 485-486
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33744920863&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Problems and techniques
AU - Ipsen, I.
T2 - SIAM Review
DA - 2006///
PY - 2006///
VL - 48
IS - 1
SP - 41-42
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33644586567&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Problems and Techniques
AU - Ipsen, Ilse
T2 - SIAM Review
AB - The Problems and Techniques section features two papers: one on differential equations, and one on sums containing binomial coefficients and their logarithms. The deflection u(x) of a beam at point x can be described by an ordinary differential equation (ODE) of fourth order, such as, for instance, $$ \hspace*{58pt}\frac{ \mbox{ \textit{d}$^{\mbox{\fontsize{6pt}{6pt}\selectfont 4}}$\textit{u}(\textit{x})}} {\mbox{ \textit{dx}$^{\mbox{\fontsize{6pt}{6pt}\selectfont 4}}$}} \mbox{ = – 100,\qquad 0 $\leq$ \textit{x} $\leq$ 1.} $$ In this specific example the vertical load on the beam is uniform, as is the bending stiffness, and the beam has length 1. A unique solution u(x) exists if appropriate boundary conditions are prescribed, e.g., u(0) = u(1) = u$^{\prime}$(0) = u$^{\prime}$(1) = 0, which means that the beam is fixed at both ends. But what if the beam isn't fixed and we don't know the boundary conditions precisely? What if we have only bounds on the deflection and rotation at the endpoints, that is, inequalities of the form –1 $\leq$ u(x) $\leq$ 1 and –1 $\leq$ u$^{\prime}$(x) $\leq$ 1 for x = 0 and x = 1? Does a solution still exist? Enrique Castillo, Antonio Conejo, Carmen Castillo, and Roberto Mínguez, in “Solving Ordinary Differential Equations with Range Conditions,” show that it does indeed. The authors present a method to determine all solutions for linear ODEs whose boundary conditions are linear and are prescribed within intervals (or ranges) rather than at single points. Based on the inequalities in the boundary conditions, they formulate a system of linear inequalities. The solutions to this system represent coefficients in a linear combination that describes all solutions of the ODE. The authors also discuss tests for existence and uniqueness of solutions. The second paper, “Difference of Sums Containing Products of Binomial Coefficients and Their Logarithms,” is concerned with the expression $$ \hspace*{59pt}\displaystyle\frac{\mbox{1}} {\mbox{2$^{\mbox{\fontsize{6pt}{6pt}\selectfont \textit{n}}}$}} \mbox{$\displaystyle\sum_{\mbox{\fontsize{6pt}{6pt}\selectfont \textit{k} = 0}} ^{\mbox{\fontsize{6pt}{6pt}\selectfont \textit{n}}}$} \left(\displaystyle\frac{\mbox{1}}{\mbox{2}} \mbox{$\alpha_{\mbox{\fontsize{6pt}{6pt}\selectfont \textit{k}}}$} \mbox{ ln } \alpha_{\mbox{\fontsize{6pt}{6pt}\selectfont \textit{k}}}-\beta_{\mbox{\fontsize{6pt}{6pt}\selectfont \textit{k}}} \mbox{ ln } \beta_{\mbox{\fontsize{6pt}{6pt}\selectfont \textit{k}}} \right)\mbox{,} \qquad \mbox{$\alpha_{\mbox{\fontsize{6pt}{6pt}\selectfont \textit{k}}}$} \equiv {\mbox{\textit{n} + 1}\choose \mbox{\textit{k}}}\mbox{,}\quad \mbox{$\beta_{\mbox{\fontsize{6pt}{6pt}\selectfont \textit{k}}}$} \equiv {\mbox{\textit{n}}\choose \mbox{\textit{k}}}\mbox{,} $$ which occurs in an analysis of covert communication channels and is related to the capacity of the covert channel. Authors Allen Miller and Ira Moskowitz use binomial identities to simplify the expression, show that it increases monotonically with n, and prove that it converges to ln 2 as n $\rightarrow \infty$.
DA - 2006/1//
PY - 2006/1//
DO - 10.1137/siread000048000002000305000001
VL - 48
IS - 2
SP - 305-305
ER -
TY - JOUR
TI - Problems and Techniques
AU - Ipsen, Ilse
T2 - SIAM Review
AB - Readers may be surprised to learn that there is something on which everybody in my department agrees: the heating system is absolutely ineffective. Some offices get too hot too fast (usually inhabitated by some who like it cold), while other offices (like mine, unfortunately) take forever to become even slightly warm. The building is heated by a network of pipes through which hot steam is circulated. Question: How to design a heating system that delivers the same amount of steam to each office as fast as possible, thereby ensuring that all offices have the same temperature as fast as possible? Answer: Construct a specific matrix, called a weighted Laplacian, and choose the weights so as to maximize its second largest eigenvalue. The weights tell us how wide each pipe needs to be. Of course, this is a constrained optimization problem, because we are on a budget and can afford only a limited amount of material for the pipes. A more general problem is discussed by Jun Sun, Stephen Boyd, Lin Xiao, and Persi Diaconis in their paper “The Fastest Mixing Markov Process on a Graph and a Connection to a Maximum Variance Unfolding Problem.” They express the problem of maximizing the second largest eigenvalue of the Laplacian as a semidefinite program. The dual of this program has a simple geometric interpretation: It’s the problem of positioning n points in n‐space, so that they are as far apart as possible, but do not exceed prescribed distances between any two points. Coming back now to the heating issues in my department, we have been promised a new building. Ground breaking is to start anytime now (or so, at least, we are told). I have been thinking about giving this paper to the architects; it might inspire them to install a more effective heating system. In the well‐written paper “Globalization Techniques for Newton–Krylov Methods and Applications to the Fully Coupled Solution of the Navier–Stokes Equations,” Roger Pawlowski, John Shadid, Joseph Simonis, and Homer Walker discuss methods for the solution of systems of nonlinear equations $F(u)=0$. Such systems arise, for instance, when one discretizes partial differential equations to solve fluid flow problems. Arguably the most popular method for solving $F(u)=0$ is Newton’s method. It starts from an initial approximation $u_0$ and produces successively better (we hope) iterates $u_{k+1}$ as updates of the previous iterate, $u_{k+1}=u_k+s_k$. The step $s_k$ is computed as the solution to the linear system $F^{\prime}(u_k)s_k=-F(u_k)$, where the Jacobian $F^{\prime}(u)$ is the matrix of derivatives. When the linear system is solved by a Krylov space method, for instance, one talks about a Newton–Krylov method. Convincing Newton’s method to converge to the solution is not always easy, especially when the initial approximation $u_0$ is far away. A variety of strategies is available that can enhance the performance of Newton’s method. The authors discuss two. To increase robustness, one can solve the linear systems more or less accurately; this is done by terminating the linear system solution as soon as the residual norm $\|F^{\prime}(u_k)+F(u_k)s_k\|$ falls below a specified forcing term. To improve the chances for convergence, one can globalize Newton’s method by changing the length of the step $s_k$ (as opposed to its direction), or by choosing a step $s_k$ that minimizes the residual norm over a particular region. The authors prove convergence results, and perform numerical experiments on standard benchmark problems to compare different forcing terms and globalization strategies. Are you one of those people who firmly believes that there is one and only one way to win a tennis match? And that’s by subjecting your opponent to that impossible‐to‐return 700‐horse‐power serve? Yes? Then we might have just the paper for you. In “Monte Carlo Tennis,” Paul Newton and Kamran Aslam analyze the probability of winning in tennis, and express it in terms of the probability that a player wins a point when serving. In previous work, Paul Newton and coauthor Joe Keller had assumed that this probability is constant—throughout the whole match, and even a tournament. This amounts to assuming that points in tennis are random variables, independently and identically distributed (i.i.d.). However, this assumption fails to account for the “hot‐hand,” when everything goes just swimmingly; the “back‐to‐the‐wall” effect, when miraculous feats become possible in the face of looming loss; or simply the adjustment to new tennis balls. Do these things really make a difference? Is the i.i.d. assumption unrealistic? Paul Newton and Kamran Asham perform Monte Carlo simulations in MATLAB to answer this question. Read the paper if you want to know what they come up with.
DA - 2006/1//
PY - 2006/1//
DO - 10.1137/siread000048000004000679000001
VL - 48
IS - 4
SP - 679-680
ER -
TY - CONF
TI - Computer Optimized Gun Design
AU - Ives, R. L.
AU - Read, M.E.
AU - Bui, Thuc
AU - David, John
AU - Tran, Hien
T2 - >2006 Joint 31st International Conference on Infrared Millimeter Waves and 14th International Conference on Teraherz Electronics
AB - Computer optimization can explore a wider parameter space than practical with manual design, particularly for 3D geometries. This allows rapid, economical development of higher performance devices. The proliferation of parametric solid modeling programs allows optimization of both geometry and operating parameters. This presentation described computer optimization in the 3D trajectory code beam optics analysis (BOA). This is possible because meshing in BOA is completely automatic, allowing the program to be controlled by the optimization routines.
C2 - 2006/9//
C3 - 2006 Joint 31st International Conference on Infrared Millimeter Waves and 14th International Conference on Teraherz Electronics
DA - 2006/9//
DO - 10.1109/icimw.2006.368358
PB - IEEE
SN - 1424403995 1424404002
UR - http://dx.doi.org/10.1109/icimw.2006.368358
DB - Crossref
ER -
TY - JOUR
TI - Stochastic portfolio optimization with log utility
AU - Pang, Tao
T2 - International Journal of Theoretical and Applied Finance
AB - A portfolio optimization problem on an infinite time horizon is considered. Risky asset price obeys a logarithmic Brownian motion, and the interest rate varies according to an ergodic Markov diffusion process. Moreover, the interest rate fluctuation is correlated with the risky asset price fluctuation. The goal is to choose optimal investment and consumption policies to maximize the infinite horizon expected discounted log utility of consumption. A dynamic programming principle is used to derive the dynamic programming equation (DPE). The explicit solutions for optimal consumption and investment control policies are obtained. In addition, for a special case, an explicit formula for the value function is given.
DA - 2006///
PY - 2006///
DO - 10.1142/s0219024906003858
VL - 9
IS - 6
SP - 869-887
SN - 0219-0249 1793-6322
UR - http://dx.doi.org/10.1142/s0219024906003858
KW - Portfolio optimization
KW - dynamic programming equations
KW - subsolution and supersolutions
ER -
TY - CONF
TI - Comparison between failure detection test signals for continuous systems and sampled-data systems
AU - Choe, D.
AU - Campbell, S. L.
AU - Nikoukhah, R.
T2 - Proceedings of the 45th IEEE Conference on Decision and Control
AB - In active failure detection it is essential to have auxiliary signal inputs that are capable of identifying the status of observed systems while the operations of the systems are minimally disturbed by the extra input. Recently, two signal-design-algorithms for active failure detection were introduced: one that computes optimal continuous detection signals for continuous systems (CS) and the other that designs optimal piecewise-constant signal inputs for sampled-data systems (SDS). In some applications simple piecewise constant inputs are sought. In this paper, we combine the key ideas of the two previous algorithms and present an algorithm that finds optimal piecewise-constant signals for continuous systems. This modified algorithm provides a suboptimal detection signal inputs for continuous systems and would appear to be greatly faster than the original CS algorithm. We also compare the three algorithms and the corresponding optimal signals through a computational experiment
C2 - 2006///
C3 - Proceedings of the 45th IEEE Conference on Decision and Control
DA - 2006///
DO - 10.1109/cdc.2006.377349
PB - IEEE
SN - 1424401712
UR - http://dx.doi.org/10.1109/cdc.2006.377349
DB - Crossref
ER -
TY - CONF
TI - Model Based Failure Detection using Test Signals from Linearizations: A Case Study
AU - Campbell, S.
AU - Drake, K.
AU - Andjelkovic, I.
AU - Sweetingham, K.
AU - Choe, D.
T2 - 2006 IEEE Conference on Computer-Aided Control Systems Design
C2 - 2006/10//
C3 - 2006 IEEE Conference on Computer-Aided Control Systems Design
DA - 2006/10//
DO - 10.1109/cacsd.2006.285526
PB - IEEE
SN - 0780397975
UR - http://dx.doi.org/10.1109/cacsd.2006.285526
DB - Crossref
ER -
TY - CONF
TI - Robust detection of incipient faults: an active approach
AU - Nikoukhah, R.
AU - Campbell, S. L.
T2 - 2006 14th Mediterranean Conference on Control and Automation
AB - The methodology of auxiliary signal design for robust failure detection based on multi-model formulation of normal and failed systems is used to study the problem of incipient fault detection. Here, the fault is modeled as a drift in a system parameter, and an auxiliary signal is to be designed to enhance the detection of variations in this parameter. It is shown that it is possible to consider the model of the system with a drifted parameter as a second model and use the multi-model framework for designing the auxiliary signal by considering the limiting case as the parameter variation goes to zero. The result can be applied very effectively to early detection problems where small parameter variations should be detected.
C2 - 2006/6//
C3 - 2006 14th Mediterranean Conference on Control and Automation
DA - 2006/6//
DO - 10.1109/med.2006.328694
PB - IEEE
SN - 0978672011 0978672003
UR - http://dx.doi.org/10.1109/med.2006.328694
DB - Crossref
ER -
TY - CONF
TI - Trust representation and aggregation in a distributed agent system
AU - Wang, Y.
AU - Singh, M.P.
C2 - 2006///
C3 - Proceedings of the National Conference on Artificial Intelligence
DA - 2006///
VL - 2
SP - 1425-1430
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33750688177&partnerID=MN8TOARS
ER -
TY - CONF
TI - Specifying and resolving preferences among agent interaction patterns
AU - Mallya, A.U.
AU - Singh, M.P.
AB - A strength of commitment protocols is that they enable agents to act flexibly, thereby enabling them to accommodate varying local policies and respond to exceptions. A consequent weakness is that commitment protocols thus fail to distinguish between possible executions that are normal and those that may be allowed but are not ideal. This paper develops an approach for specifying preferences among executions that are allowed by a protocol. It captures sets of executions via an event constraint specification language and gives them a denotational characterization based on branching-time models. This paper develops algorithms for choosing the best execution path by considering the interplay between the preference specification of a protocol and local policies of agents interacting using the protocol, thereby giving the specifications a natural operational characterization. The value of the concepts developed is illustrated by its application to a recent practical framework for protocols called OWL-P. Further, the paper shows that the operational and denotational characterizations of preference specifications coincide.
C2 - 2006///
C3 - Proceedings of the International Conference on Autonomous Agents
DA - 2006///
DO - 10.1145/1160633.1160886
VL - 2006
SP - 1361-1368
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-34247231533&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Secure data management in reactive sensor networks
T2 - Lecture Notes in Computer Science
AB - A wireless sensor network (WSN), an ad hoc network of resource constrained sensor nodes, has become an attractive option for monitoring applications. The wide use of sensor networks is due to the cheap hardware and detailed information they provide to the end user. As with every network of every computing device, security is one of the key issue of sensor networks. The resource constrained nature of sensor nodes make the security quite challenging. The sensor networks are prone to many kinds of security attack viz. report fabrication attack, denial of service attack, Sybil attack, traffic analysis attack, node replication attack, physical attack etc. The report fabrication attack is a security attack in which the adversary tries to generate bogus reports by compromising the sensor nodes. This paper proposes a security solution that makes cluster based sensor networks resilient to report fabrication attacks. The proposed solution relies on symmetric key mechanisms, appropriate for random deployment and also handles the node failures.
DA - 2006///
PY - 2006///
DO - 10.1007/11961635_16
UR - https://publons.com/publon/21294465/
ER -
TY - CHAP
TI - Producing Compliant Interactions: Conformance, Coverage, and Interoperability
AU - Chopra, Amit K.
AU - Singh, Munindar P.
T2 - Declarative Agent Languages and Technologies IV
PY - 2006///
DO - 10.1007/11961536_1
SP - 1-15
OP -
PB - Springer Berlin Heidelberg
SN - 9783540689591 9783540689614
UR - http://dx.doi.org/10.1007/11961536_1
DB - Crossref
ER -
TY - BOOK
TI - Service-Oriented Computing: Semantics, Processes, Agents
AU - Singh, Munindar P.
AU - Huhns, M.N.
AB - Traditional approaches to software development - the ones embodied in CASE tools and modeling frameworks - are appropriate for building individual software components, but they are not designed to face the challenges of open environments. Service-oriented computing provides a way to create a new architecture that reflects components' trends toward autonomy and heterogeneity. We thus emphasize SOC concepts instead of how to deploy Web services in accord with current standards. To begin the series, we describe the key concepts and abstractions of SOC and the elements of a corresponding engineering methodology.
DA - 2006///
PY - 2006///
DO - 10.1002/0470091509
PB - Chichester; Hoboken, NJ: Wiley
SE - 1-549
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84947336240&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Report on the fourth international joint conference on Autonomous Agents and Multiagent Systems (AAMAS 2005)
AU - Koenig, S.
AU - Kraus, S.
AU - Singh, M.P.
AU - Wooldridge, M.
T2 - AI Magazine
DA - 2006///
PY - 2006///
VL - 27
IS - 1
SP - 103-107
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33645745843&partnerID=MN8TOARS
ER -
TY - CHAP
TI - OWL-P: A Methodology for Business Process Development
AU - Desai, Nirmit
AU - Mallya, Ashok U.
AU - Chopra, Amit K.
AU - Singh, Munindar P.
T2 - Agent-Oriented Information Systems III. AOIS 2005
A2 - Kolp, M.
A2 - Bresciani, P.
A2 - Henderson-Sellers, B.
A2 - Winikoff, M.
T3 - Lecture Notes in Computer Science
AB - Business process modelling and enactment are notoriously complex, especially in open settings where the business partners are autonomous, requirements must be continually finessed, and exceptions frequently arise because of real-world or organizational problems. Traditional approaches, which attempt to capture processes as monolithic flows, have proved inadequate in addressing these challenges. We propose an agent-based approach for business process modelling and enactment which is centred around the concepts of commitment-based agent interaction protocols and policies. A (business) protocol is a modular, public specification of an interaction among different roles. Such protocols, when integrated with the internal business policies of the participants, yield concrete business processes. We show how this reusable, refinable and evolvable abstraction simplifies business process design and development.
PY - 2006///
DO - 10.1007/11916291_6
VL - 3529 LNAI
SP - 79–94
PB - Springer
SN - 9783540482918 9783540482925
SV - 3529
UR - http://dx.doi.org/10.1007/11916291_6
ER -
TY - CHAP
TI - Introducing Preferences into Commitment Protocols
AU - Mallya, Ashok U.
AU - Singh, Munindar P.
T2 - Agent Communication II
A2 - Dignum, Frank P.M.
A2 - van Eijk, Roger M.
A2 - Flores, Roberto
T3 - Lecture Notes in Computer Science
PY - 2006///
DO - 10.1007/978-3-540-68143-4_10
SP - 136–149
PB - Springer
SN - 9783540681427 9783540681434
SV - 3859
UR - http://dx.doi.org/10.1007/978-3-540-68143-4_10
ER -
TY - CONF
TI - Multiagent policy architecture for virtual business organizations
AU - Udupi, Y.B.
AU - Singh, M.P.
AB - A virtual organization (VO) is a dynamic collection of entities (individuals, enterprises, and information resources) collaborating on some computational activity. VOs are an emerging means to model, enact, and manage large-scale service computations. VOs consist of autonomous, heterogeneous members, often exhibiting complex behaviors. Thus VOs are a natural match for policy-based approaches. Traditional policy-based frameworks emphasize reactive behaviors, wherein an external request causes a policy engine to compute a response. However, business service settings require richer policies and call for proactive behaviors. A business not only must respond to explicit requests, but also monitor its environment, collate events, and potentially act in anticipation of events in order to ensure that its policies are satisfied. Autonomous, heterogeneous, proactive entities are best modeled as agents and, therefore, VOs are best understood as multiagent systems. Our main contributions are (1) a proactive multiagent policy-based architecture, (2) a hierarchical model of policy monitoring, compliance checking, and enforcement for VOs, and (3) a formalization of VOs. We evaluate our approach using a real business service scenario
C2 - 2006///
C3 - Proceedings - 2006 IEEE International Conference on Services Computing, SCC 2006
DA - 2006///
DO - 10.1109/SCC.2006.75
SP - 44-51
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-35148823347&partnerID=MN8TOARS
ER -
TY - BOOK
TI - Introducing preferences into commitment protocols
AU - Mallya, A.U.
AU - Singh, M.P.
DA - 2006///
PY - 2006///
VL - 3859 LNAI
SE - 136-149
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-77956013565&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Interaction-oriented programming: Concepts, theories, and results on commitment protocols
T2 - Lecture Notes in Computer Science
DA - 2006///
PY - 2006///
DO - 10.1007/11941439_3
UR - https://publons.com/publon/21294469/
ER -
TY - CONF
TI - Contract enactment in virtual organizations: A commitment-based approach
AU - Udupi, Y.B.
AU - Singh, M.P.
C2 - 2006///
C3 - Proceedings of the National Conference on Artificial Intelligence
DA - 2006///
VL - 1
SP - 722-727
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33750708550&partnerID=MN8TOARS
ER -
TY - CONF
TI - An overview of business process adaptations via protocols
AU - Desai, N.
AU - Chopra, A.K.
AU - Singh, M.P.
AB - Business process management in open environments poses special challenges. In particular, such environments are dynamic, thereby requiring frequent changes in business processes. Current business process modeling approaches handle such changes in an ad hoc manner, and lack a principled means of determining what needs to be changed and where.This paper provides an overview of process adaptability through a novel application of business protocols, especially of protocol composition, introduced in our previous work. Through a real business scenario of auto-insurance claim processing, this paper briefly describes how a wide range of adaptations can be handled naturally and systematically via protocol composition. The illustrated adaptations have been evaluated via a prototype.
C2 - 2006///
C3 - Proceedings of the International Conference on Autonomous Agents
DA - 2006///
DO - 10.1145/1160633.1160879
VL - 2006
SP - 1326-1328
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-34247252465&partnerID=MN8TOARS
ER -
TY - CONF
TI - Contextualizing commitment protocols
AU - Chopra, A.K.
AU - Singh, M.P.
AB - Commitment protocols are modularized specifications of interactions understood in terms of commitments. Purchase is a classic example of a protocol. Although a typical protocol would capture the essence of the interactions desired, in practice, it should be adapted depending on the circumstances or context and the agents' preferences based on that context. For example, when applying purchase in different contexts, it may help to allow sending reminders for payments or returning goods to obtain a refund. We contextualize a protocol by adapting it via different transformations.Our contributions are the following: (1) a protocol is transformed by composing its specification with a transformer specification; (2) contextualization is characterized operationally by relating the original and transformed protocols; and (3) contextualization is related to protocol compliance.
C2 - 2006///
C3 - Proceedings of the International Conference on Autonomous Agents
DA - 2006///
DO - 10.1145/1160633.1160884
VL - 2006
SP - 1345-1352
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-34247185859&partnerID=MN8TOARS
ER -
TY - CONF
TI - Business process adaptations via protocols
AU - Desai, N.
AU - Chopra, A.K.
AU - Singh, M.P.
AB - Business process management in service-oriented computing (SOC) environments poses special challenges. In particular, SOC environments are dynamic, thereby requiring frequent changes in business processes. Current business process modeling approaches handle such changes in an ad hoc manner, and lack a principled means of determining what needs to be changed and where. This paper addresses process adaptability through a novel application of business protocols, especially of protocol composition, introduced in our previous work. Through a real business scenario of auto-insurance claim processing, this paper demonstrates how a wide range of adaptations can be handled naturally and systematically via protocol composition. The illustrated adaptations have been evaluated via a prototype
C2 - 2006///
C3 - Proceedings - 2006 IEEE International Conference on Services Computing, SCC 2006
DA - 2006///
DO - 10.1109/SCC.2006.30
SP - 103-110
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-35148864924&partnerID=MN8TOARS
ER -
TY - JOUR
TI - All-Integer Dual Simplex for Binate Cover Problems (Draft)
AU - Stallmann, Matthias
DA - 2006///
PY - 2006///
UR - https://people.engr.ncsu.edu/mfms/Publications/int-dual.pdf
ER -
TY - JOUR
TI - Using Water Transfers to Manage Supply Risk
AU - Characklis, G W
AU - Kirsch, B R
AU - Ramsey, J
AU - Dillard, K E M
AU - Kelley, C T
T2 - Proceedings of Symposium on Safe Drinking Water: Where Science Meets Policy
DA - 2006///
PY - 2006///
ER -
TY - JOUR
TI - Reduced order models for nonlinear least squares problems
AU - Kelley, C T
AU - Sorensen, D
AU - Reese, J P
AU - Winton, C
DA - 2006///
PY - 2006///
ER -
TY - CONF
TI - Simulating Non-{D}arcy Flow through Porous Media using {S}undance
AU - Reese, J P
AU - Long, Kevin
AU - Kelley, C T
AU - Miller, C T
AU - Gray, W G
C2 - 2006///
C3 - Proceedings of Computational Methods in Water Resources XVI
DA - 2006///
SP - Paper number 148, 8 pages
ER -
TY - JOUR
TI - {SETraNS} Manual: Simulation of Electronic Transport in Nanoscale Structures
AU - Lasater, M S
AU - Recine, Greg
AU - Kelley, C T
AU - Woolard, D L
AU - Zhao, P
DA - 2006///
PY - 2006///
ER -
TY - CONF
TI - Simulating Nanoscale Devices
AU - Lasater, M S
AU - Kelley, C T
AU - Salinger, A
AU - Zhao, P
AU - Woolard, D L
A2 - Iwai, H
A2 - Nishi, Y
A2 - Shur, M S
A2 - Wong, H
C2 - 2006///
C3 - International Journal of High Speed Electronics and Systems
DA - 2006///
VL - 16
SP - 677-690
PB - World Scientific
ER -
TY - JOUR
TI - Parallel Parameter Study of the {Wigner-Poisson} Equations for {RTDs}
AU - Lasater, M S
AU - Kelley, C T
AU - Salinger, A
AU - Woolard, D L
AU - Zhao, P
T2 - Computers and Mathematics with Applications
DA - 2006///
PY - 2006///
VL - 51
SP - 1677-1688
ER -
TY - CONF
TI - Nonlinear multilevel iterative methods for multiscale models of air/water flow in porous media
AU - Kees, C E
AU - Farthing, M W
AU - Howington, S E
AU - Jenkins, E W
AU - Kelley, C T
C2 - 2006///
C3 - Proceedings of Computational Methods in Water Resources XVI
DA - 2006///
SP - Paper number 256, 8 pages
ER -
TY - JOUR
TI - Model Reduction for Nonlinear Least Squares
AU - Kelley, C T
AU - Sorensen, D
AU - Reese, J P
AU - Winton, C
DA - 2006///
PY - 2006///
ER -
TY - JOUR
TI - Special issue on accurate solution of eigenvalue problems
AU - Ipsen, I.C.F.
T2 - SIAM Journal on Matrix Analysis and Applications
DA - 2006///
PY - 2006///
VL - 28
IS - 4
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-35348933724&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Problems and techniques: Introduction
AU - Ipsen, I.C.F.
T2 - SIAM Review
DA - 2006///
PY - 2006///
VL - 48
IS - 2
SP - 485-486
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33744920863&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Problems and Techniques
AU - Ipsen, Ilse
T2 - SIAM Review
AB - Related DatabasesWeb of Science You must be logged in with an active subscription to view this.Article DataHistoryPublished online: 17 February 2012Publication DataISSN (print): 0036-1445ISSN (online): 1095-7200Publisher: Society for Industrial and Applied MathematicsCODEN: siread
DA - 2006/1//
PY - 2006/1//
DO - 10.1137/siread000048000003000485000001
VL - 48
IS - 3
SP - 485-485
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33751424677&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Problems and Techniques
AU - Ipsen, Ilse
T2 - SIAM Review
AB - The Problems and Techniques section in this issue contains three papers on very different topics: achieving reliability through optimization, improving the solution of systems of linear equations by preconditioning, and determining asymptotic expansion of integrals in Laplace form. Reliability is an important aspect in engineering design. One can make a system (such as a car) more reliable by introducing redundancy (e.g., carrying around a spare tire) or by making individual system components more reliable (e.g., using better material to manufacture car parts). In the first paper, James Falk, Nozer Singpurwalla, and Yefim Vladimirsky pursue the latter approach, opting to increase the reliability of individual components. This is called reliability allocation. Why not just adopt the simplest strategy and make all components of a system more reliable? This could be way too expensive. Consider, for instance, my Volkswagen GTI, a system with probably at least 3000 different components. Let's measure the reliability of the GTI by whether it drives or not. Replacing the plastic cup holder by one made from aluminum would cost a lot but would do nothing to increase the car's reliability. That's because the cup holder does not contribute to the drivability of the car (provided we disregard the driver who needs the cupholder for coffee to stay awake). However, replacing the plastic radiator by one made from aluminum costs only slightly more, but increases the reliability of the car significantly because the added cooling capacity prevents the engine from overheating when one wants to drive really fast. The question therefore is, which components of a system should we make more reliable, while keeping an eye on the cost? The authors propose to maximize a utility function that is aware of the interaction among components of the system, and trades off the cost of increasing reliability with greater probability of system functioning. In the second paper, Luis González presents a well-written and elegant analysis to justify the effectiveness of a particular approach for solving systems of linear equations. Systems of linear equations Ax = b whose coefficient matrix A has large dimension and is sparse (i.e., contains many zero elements) occur, for instance, whenever partial differential equations are discretized. Direct methods for solving Ax = b, such as Gaussian elimination, can be too expensive when they introduce too many nonzero elements during the course of the computation. In this case one may resort to iterative methods, which in successive iterations produce better and better approximations—or so one hopes. Unless one is lucky with one's matrix A, though, iterative methods can be slow and unreliable. Efficiency and reliability can be improved by preconditioning the system, i.e., transforming Ax = b into a preconditioned system (AN) y = b, where the matrix N is chosen such that the system (AN) y = b can be solved quickly, and the original solution x = Ny can be recovered easily. In this paper, the matrix N is chosen as an approximate inverse of A, so that the preconditioned matrix AN is close to the identity matrix I, and iterative methods applied to (AN) y = b converge fast. To ensure that recovery of the solution x = Ny is still easy, restrictions must be placed on N. The paper sets a very general context by assuming that N comes from some subspace S of matrices. Formally, the criterion is to choose N such that the residual $\|$AN – I$\|_{\fontsize{6pt}{6pt}\selectfont\textit{F}}$ is minimized, in the Frobenius norm, over all matrices from the subspace S. The idea for justifying the effectiveness of the preconditioner N is to cast the minimization problem in the form min$_{\fontsize{6pt}{6pt}\selectfont\textit{Q}}\|$Q – I$\|_{\fontsize{6pt}{6pt}\selectfont\textit{F}}$, where Q is a matrix from the subspace AS. The problem now amounts to analyzing orthogonal projections Q of the identity matrix I (hence the title of the paper). It turns out that if the smallest singular value of the preconditioned matrix AN is close to one and if also the smallest eigenvalue in magnitude is close to one, then everything works out: the residual $\|$AN – I$\|_{\fontsize{6pt}{6pt}\selectfont\textit{F}}$ is small, the matrix AN is well-conditioned, and its departure from normality is small. These are exactly the conditions that guarantee (in exact arithmetic) the effectiveness and reliability of the preconditioner N. To understand what's going on in the third paper, let's start with an example. The Gamma function can be represented as $$\hspace*{21pt}\hskip3pc \mbox{$\Gamma$($\lambda$ + 1) = $\displaystyle\int_{\mbox{\fontsize{6pt}{6pt}\selectfont 0}}^{\infty}$ u$^{\lambda}e^{\fontsize{6pt}{6pt}\selectfont\mbox{\fontsize{6pt}{6pt}\selectfont –}\textit{u}}$\textit{du},} $$ where $\lambda> $ 0. If we are interested in how $\Gamma$ depends on the positive parameter $\lambda$, we can determine the asymptotic expansion $$\hskip3pc\hspace*{21pt}\mbox{$\Gamma$($\lambda$ + 1) ~ \textit{e}$^{\mbox{\fontsize{6pt}{6pt}\selectfont–}\lambda} \lambda^{\mbox{\fontsize{6pt}{6pt}\selectfont$\lambda$ +\,1}}$ $\left(\frac{\displaystyle\mbox{2} \pi}{\mbox{\fontsize{9}{9pt}\selectfont$\lambda$}}\right)^{\mbox{\fontsize{6pt}{6pt}\selectfont 1/2}} \left[\mbox{1 + }{\mbox{1} \over \mbox{12}\mbox{\fontsize{9}{9pt}\selectfont$\lambda$}}\mbox{\,+\,}{\mbox{1}\over \mbox{288}\,\mbox{\fontsize{9}{9pt}\selectfont$\lambda$}^{\mbox{\fontsize{6pt}{6pt}\selectfont 2}}}\mbox{\,+\,}\cdots\right].$} $$ One way of obtaining such an asymptotic expansion is to change variables, u = $\lambda$(1 + x),set h(x) $\equiv$ x – log(1 + x), and write $$\hspace*{0pt}\hskip3pc\hspace*{26pt}\mbox{$\Gamma$($\lambda$ + 1) = \textit{e}$^{\mbox{\fontsize{6pt}{6pt}\selectfont–}\lambda} \lambda^{\mbox{\fontsize{6pt}{6pt}\selectfont$\lambda$ +\,1}} \displaystyle\int_{-1}^{\infty}$ \textit{e}$^{\mbox{\fontsize{6pt}{6pt}\selectfont–$\lambda$\textit{h}(\textit{x})}}$\textit{dx}.} $$ The integral is in Laplace form, i.e., it is of the form $$\hskip3pc\hspace*{23pt}\mbox{\textit{I}($\lambda$) = $\displaystyle\int_{\fontsize{6pt}{6pt}\selectfont\textit{a}}^{\fontsize{6pt}{6pt}\selectfont\textit{b}} \phi$(\textit{x})\textit{e}$^{\mbox{\fontsize{6pt}{6pt}\selectfont–$\lambda$\textit{h}(\textit{x})}}\textit{dx}$,} $$ where, in this special case, $\phi$(x) = 1, a = –1, and b = $\infty$. Here is the reason why Laplace's form is important, and why it was named after Laplace: Laplace observed that the major contributions to the integral I($\lambda$) come from those points where e$^{\fontsize{6pt}{6pt}\selectfont{-\textit{h}(\textit{x})}}$ attains its greatest values. He showed that if, among other things, h(x) has a minimum only at the left endpoint x = a, then the integral has the asymptotic expansion $$\hskip3pc \mbox{\textit{I}($\lambda$) ~ \textit{e}$^{\mbox{\fontsize{6pt}{6pt}\selectfont–$\lambda$\textit{h}(\textit{a})}}\> \displaystyle\sum_{\fontsize{6pt}{6pt}\selectfont\textit{s = 0}}^{\infty} \frac{\mbox{\textit{d}$_{\fontsize{6pt}{6pt}\selectfont\textit{s}}$}} {\lambda^{\mbox{\fontsize{6pt}{6pt}\selectfont($\alpha$ + \textit{s})$/\mu$}}}\qquad \mbox{as}~\lambda\rightarrow\infty$, } $$ where the numbers $\alpha$ and $\mu$ come from expansions of h(x) and $\phi$(x), respectively. However, symbolic computation of the coefficients d$_{\fontsize{6pt}{6pt}\selectfont\textit{s}}$ in asymptotic expansions of integrals in Laplace form I($\lambda$) has often been intractable. In his paper, John Wojdylo presents explicit expressions for the coefficients d$_{\fontsize{6pt}{6pt}\selectfont\textit{s}}$ that are more efficient and simpler than existing ones, and which should facilitate symbolic implementations. Laplace's method is one of several popular methods for determining asymptotic expansions of integrals (integration by parts is another). Asymptotic expansions can be more advantageous than numerical methods because they can reveal dependence on parameters that are physically significant, they can be differentiated or integrated exactly, and they can be more accurate.
DA - 2006/1//
PY - 2006/1//
DO - 10.1137/siread000048000001000041000001
VL - 48
IS - 1
SP - 41-42
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33644586567&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Differential-Algebraic Equations
AU - Campbell, Stephen
AU - März, Roswitha
AU - Rentrop, Peter
AU - Petzold, Linda
T2 - Oberwolfach Reports
AB - The topic of Differential Algebraic Equations (DAEs) began to attract significant research interest in applied and numerical mathematics in the early 1980's. Today, a quarter of a century later, DAEs are an independent field of research, which is gaining in importance and becoming of increasing interest for both applications and mathematical theory.\\\ This Oberwolfach workshop brought together 48 experts in applied mathematics, among them, on the one hand, some who have already influenced and formed the developments of the field, and on the other hand, some very young researchers who have shown outstanding creativity and competence in connection with their PhD theses and thus raise great hopes for further advances.\\\ The 16 female and 32 male scientists came from 13 countries to meet and work together in the wonderful, unique Oberwolfach atmosphere, which stimulated a fruitful and pleasant collaboration.\\\ The schedule comprised a total of 34 presentations, 18 of which were arranged into 14 survey lectures (some of them with more than one speaker) offering a broader treatment of a particular subject. 16 shorter contributions supplemented the scientific programmme. The areas can be classified (of course with large overlap) into 4 groups: \begin{itemize} \item abstract differential algebraic systems, coupled systems, partial differential algebraic systems; \item analysis of (ordinary) differential algebraic equations and application of numerical methods to problems having new mathematical complexity; \item innovative and improved numerical integration methods to solve highly complex application problems; \item optimization with constraints described by DAEs and control problems concerning DAEs. \end{itemize} The broad range of these areas and the diversity of the participants stimulated fruitful discussions between the different branches and gave rise to new contacts and collaborations. A considerable gain in knowledgde and progress became obvious, which includes the formulation of open questions and challenges for the future.\\\ We are grateful to the Mathematisches Forschungsinstitut Oberwolfach for providing an inspiring setting for this workshop.
DA - 2006///
PY - 2006///
DO - 10.4171/owr/2006/18
SP - 1077-1168
ER -
TY - JOUR
TI - Stochastic optimal control problems with a bounded memory
AU - Chang, M.-H.
AU - Pang, T.
AU - Pemy, Moustapha
T2 - Operations Research and Its Applications, Lecture Notes in Operations Research
DA - 2006///
PY - 2006///
VL - 6
SP - 82–94
ER -
TY - JOUR
TI - Mathematical properties and analysis of Google’s PageRank
AU - Ipsen, I.C.F.
AU - Wills, R.S.
T2 - Boletin de la Sociedad Espanola de Matematica Aplicada
DA - 2006///
PY - 2006///
VL - 34
SP - 191–196
ER -
TY - JOUR
TI - Production scheduling in a knitted fabric dyeing and finishing process
AU - Laoboonlur, P.
AU - Hodgson, T. J.
AU - Thoney, K. A.
T2 - Journal of the Textile Institute
AB - Abstract Developing detailed production schedules for dyeing and finishing operations is a very difficult task that has received relatively little attention in the literature. In this paper, a scheduling procedure is presented for a knitted fabric dyeing and finishing plant that is essentially a flexible job shop with sequence-dependent setups. An existing job shop scheduling algorithm is modified to take into account the complexities of the case plant. The resulting approach based on family scheduling is tested on problems generated with case plant characteristics.
DA - 2006/8//
PY - 2006/8//
DO - 10.1533/joti.2006.0145
VL - 97
IS - 5
SP - 391-399
KW - dyeing
KW - finishing
KW - production
KW - scheduling
KW - setups
ER -
TY - JOUR
TI - Algorithm to Systematically Reduce Human Errors in Healthcare
AU - Seastrunk, Chad Stephen
DA - 2006///
PY - 2006///
ER -
TY - CONF
TI - effective energy conservation in wireless sensor networks
AU - Tezcan, N.
AU - Wang, Wenye
AB - In this paper, we present a two-tiered scheduling scheme that provides effective energy conservation in wireless sensor networks. The effectiveness of this scheme relies on dynamically updated two-tiered scheduling architecture. We aim to prolong network lifetime, while preserving the major requirements of wireless sensor networks: coverage and connectivity. In this approach, sensors are periodically scheduled to sleep in two phases using weighted greedy algorithms. First, we establish a coverage-tier by selecting a set of sensors that covers the sensing field in order to provide fully monitoring of entire field. Sensors that are not selected for the coverage-tier, are put into sleep immediately. Then, a second tier, called connectivity-tier, is formed on top of the coverage-tier to forward the data traffic to sink node. Thus sensors, essential to coverage-tier but not in connectivity-tier may periodically sleep and become active only for sending new sensing measurement and receiving query from the sink to preserve coverage. By this way, we may allow more nodes to sleep with different sleeping behaviors, i.e., continuous sleep or periodic sleep/active. Moreover, fair energy consumption among sensors is achieved by periodically rotating the coverage and connectivity tiers. Through extensive simulations in ns2, we demonstrate that the two-tier scheduling can reduce average energy consumption up to 40% while balancing the residual energy of sensors.
C2 - 2006///
C3 - 2006 ieee international conference on communications, vols 1-12
DA - 2006///
DO - 10.1109/icc.2006.255235
SP - 3359–3364
ER -
TY - CONF
TI - Modeling and analysis of connectivity in mobile ad hoc networks with misbehaving nodes
AU - Xing, F.
AU - Wang, Wenye
AB - Mobile ad hoc networks are vulnerable to malicious attacks and failures due to their unique features, such as node mobility and dynamic network topology. The design and evaluation of routing protocols and topology control require sound analysis on network connectivity and node behaviors. However, little work has been done on how node misbehaviors affect network connectivity. Modeling and analysis of node misbehavior involves many challenges such as multiple failures caused by selfishness, mobility, and potential Denial of Service attacks. Thus, we propose a novel model to characterize node misbehaviors based on a semi-Markov process. In particular, we analyze the impact of node misbehavior on network connectivity in a mobile ad hoc network stochastically. Numerical results based on analysis and simulations are provided to demonstrate the effectiveness of our approach and results.
C2 - 2006///
C3 - 2006 ieee international conference on communications, vols 1-12
DA - 2006///
DO - 10.1109/icc.2006.254994
SP - 1879–1884
ER -
TY - CONF
TI - Metamodeling of Wi-Fi Performance
AU - Hui, J.
AU - Devetsikiotis, M.
AB - The increasing popularity of Wireless Fidelity (Wi-Fi) networks at home, in public areas and in the enterprise motivates extensive modeling and analysis of their performance measures, such as network capacity, resource requirements and quality of service (QoS) capabilities. Some of the easier performance problems can be solved by analytical modeling methods, but most of the complicated ones, involving too many factors from multiple layers, can only be answered through validated simulation models. However, an explicit mathematic model is always the most effective way to represent the system behavior and the most convenient basis for performance optimization. Here, we first advocate the application of metamodeling techniques to performance studies of Wi-Fi networks, in order to find usable, if approximate, closed-form mathematical models. Subsequently, we formulate a general metamodeling framework for Wi-Fi networks. Our results in two relevant case studies, after applying this framework, support the validity of our metamodeling methodology: our capacity metamodel for 802.11 Distributed Coordination Function (DCF) is validated by a well-known analytical model and displays an interesting log-linear relationship between capacity and number of users; our voice over Wi-Fi admission capacity metamodel gives a much tighter bound than bounds existing in the literature and composes a more practical admission control scheme. Our work, therefore, points out a new direction for future performance studies of Wi-Fi networks.
C2 - 2006///
C3 - 2006 ieee international conference on communications, vols 1-12
DA - 2006///
DO - 10.1109/icc.2006.254849
SP - 527-534
ER -
TY - CONF
TI - Dynamic wavelength sharing policies for absolute QoS in OBS networks
AU - Yang, L.
AU - Rouskas, G. N.
AB - We consider the problem of providing absolute QoS guarantees to multiple classes of users of an OBS network in terms of the end-to-end burst loss. We employ Markov decision process (MDP) theory to develop wavelength sharing policies that maximize throughput while meeting the QoS guarantees. The randomized threshold policies we obtain are simple to implement and operate, and make effective use of statistical multiplexing.
C2 - 2006///
C3 - Globecom 2006 - 2006 ieee global telecommunications conference
DA - 2006///
DO - 10.1109/glocom.2006.386
ER -
TY - CONF
TI - Challenges in service-oriented networking
AU - Callaway, R. D.
AU - Rodriguez, A.
AU - Devetsikiotis, M.
AU - Cuomo, G.
AB - We believe that application-aware networks will be a core component in the development and deployment of emerging network services. However, previous attempts at enabling application-awareness in the network have failed due to issues with security, resource allocation, and cost of deployment. The emergence of the Extensible Markup Language (XML), an open standard that enables data interoperability, along with advances in hardware, software, and networking technologies, serves as the catalyst for the development of service-oriented networking (SON). SON enables network components to become application-aware, so that they are able to understand data encoded in XML and act upon that data intelligently to make routing decisions, enforce QoS or security policies, or transform the data into an alternate representation. This paper describes the motivation behind service-oriented networking, the potential benefits of introducing application-aware network devices into service-oriented architectures, and discusses research challenges in the development of SON-enabled network appliances.
C2 - 2006///
C3 - Globecom 2006 - 2006 ieee global telecommunications conference
DA - 2006///
DO - 10.1109/glocom.2006.419
ER -
TY - CONF
TI - A novel semi-Markov smooth mobility model for mobile ad hoc networks.
AU - Zhao, M.
AU - Wang, Wenye
AB - Existing random mobility models have their limitations such as speed decay and sharp turn which have been demonstrated by the previous studies. More importantly, mobility models need to mimic the movements that abide by the physical law for accurate analysis and simulations of mobile networks. Therefore, in this paper, we propose a novel mobility model, semi-Markov smooth (SMS) model. Each SMS movement includes three consecutive phases: speed up phase, middle smooth phase, and slow down phase. Thus, the entire motion in the SMS model is smooth and consistent with the moving behaviors in real environment. Through steady state analysis, we demonstrate that SMS model has no average speed decay problem and always maintains a uniform spatial node distribution. The analytical results are validated by extensive simulation experiments. In addition, we compare the simulation results on link lifetime and percentage of node degree with random waypoint model, Gauss-Markov model and the proposed SMS model.
C2 - 2006///
C3 - Globecom 2006 - 2006 ieee global telecommunications conference
DA - 2006///
DO - 10.1109/glocom.2006.940
ER -
TY - CONF
TI - The relationship between high school mathematics and career choices among high achieving young women
AU - Berenson, S. B.
AU - Michael, J. J.
AU - Vouk, M.
C2 - 2006///
C3 - Pme 30: proceedings of the 30th conference of the international group for the psychology of mathematics education, vol 1,
DA - 2006///
SP - 220-220
ER -
TY - CONF
TI - Supply Chain Multi-Objective Simulation Optimization
AU - Joines, J.A.
AU - Thoney, K.
AU - Kay, M.G.
C2 - 2006///
C3 - Proceedings of the 4th International Industrial Simulation Conference
DA - 2006///
VL - 125-132
SP - 125-132
PB - Ostend: EUROSIS-ETI
SN - 9789077381267
ER -
TY - CHAP
TI - Probes as path seekers - A new paradigm
AU - Demers, A.
AU - List, G. F.
AU - Wallace, W. A.
AU - Lee, E. E.
AU - Wojtowicz, J. M.
T2 - Intelligent transportation systems and vehicle-highway automation 2006
AB - In a recent field experiment, a fleet of Global Positioning System—equipped vehicles shared real-time data about network travel times over a wireless network and had their path choices automatically updated accordingly. This paper describes the behavior of these 200 vehicles during the 3-month experiment and illustrates the kind of information that can be derived from the data archive that the vehicles created. Much can be learned about real-time traffic-responsive path choice, travel times, compliance, and more. Planners, designers, and system operators can learn much about the way a system behaves and can sharpen their ability to create systems that work effectively and efficiently under all ranges of use. True path seeking by probe-equipped vehicles will arise when such vehicles become a common part of the vehicle fleet.
PY - 2006///
DO - 10.3141/1944-14
SP - 107-114
PB - Washington: Transportation Research Board Natl Research Council
ER -
TY - JOUR
TI - Posterior consistency of Gaussian process prior for nonparametric binary regression
AU - Ghosal, Subhashis
AU - Roy, Anindya
T2 - ANNALS OF STATISTICS
AB - Consider binary observations whose response probability is an unknown smooth function of a set of covariates. Suppose that a prior on the response probability function is induced by a Gaussian process mapped to the unit interval through a link function. In this paper we study consistency of the resulting posterior distribution. If the covariance kernel has derivatives up to a desired order and the bandwidth parameter of the kernel is allowed to take arbitrarily small values, we show that the posterior distribution is consistent in the L1-distance. As an auxiliary result to our proofs, we show that, under certain conditions, a Gaussian process assigns positive probabilities to the uniform neighborhoods of a continuous function. This result may be of independent interest in the literature for small ball probabilities of Gaussian processes.
DA - 2006/10//
PY - 2006/10//
DO - 10.1214/009053606000000795
VL - 34
IS - 5
SP - 2413-2429
SN - 0090-5364
KW - binary regression
KW - Gaussian process
KW - Karhunen-Loeve expansion
KW - maximal inequality
KW - posterior consistency
KW - reproducing kernel Hilbert space
ER -
TY - JOUR
TI - Creating supply chain relational capital: The impact of formal and informal socialization processes
AU - Cousins, Paul D.
AU - Handfield, Robert B.
AU - Lawson, Benn
AU - Petersen, Kenneth J.
T2 - JOURNAL OF OPERATIONS MANAGEMENT
AB - Establishing closer social ties between buying and supplying organizations is increasingly cited as a critical differentiator of high and low performers in global supply chains. While the creation of relational capital within an organization is a relatively well identified concept in organizational research, comparatively little research exists on the inter-organizational socialization processes that create relational value in supply chains. In our research, we extend theoretical models of group social conduits into this context, and develop a model that posits the impact of formal and informal socialization processes on the creation of relational capital between buyers and suppliers. Results from our study of 111 manufacturing organizations in the United Kingdom suggest that informal socialization processes are important in the creation of relational capital, which in turn can lead to improved supplier relationship outcomes. Formal bridging socialization conduits appear to play a lesser role in deriving these benefits.
DA - 2006/12//
PY - 2006/12//
DO - 10.1016/j.jom.2005.08.007
VL - 24
IS - 6
SP - 851-863
SN - 1873-1317
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33751310092&partnerID=MN8TOARS
KW - supply management
KW - socialization
KW - relational capital
KW - structural equation modelling
KW - supply chain management
ER -
TY - JOUR
TI - Capacity allocation with traditional and Internet channels
AU - Dai, Yue
AU - Chao, Xiuli
AU - Fang, Shu-Cherng
AU - Nuttle, Henry L. W.
T2 - NAVAL RESEARCH LOGISTICS
AB - In this paper we study a capacity allocation problem for two firms, each of which has a local store and an online store. Customers may shift among the stores upon encountering a stockout. One question facing each firm is how to allocate its finite capacity (i.e., inventory) between its local and online stores. One firm's allocation affects the decision of the rival, thereby creating a strategic interaction. We consider two scenarios of a single-product single-period model and derive corresponding existence and stability conditions for a Nash equilibrium. We then conduct sensitivity analysis of the equilibrium solution with respect to price and cost parameters. We also prove the existence of a Nash equilibrium for a generalized model in which each firm has multiple local stores and a single online store. Finally, we extend the results to a multi-period model in which each firm decides its total capacity and allocates this capacity between its local and online stores. A myopic solution is derived and shown to be a Nash equilibrium solution of a corresponding “sequential game.” © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006
DA - 2006/12//
PY - 2006/12//
DO - 10.1002/nav.20168
VL - 53
IS - 8
SP - 772-787
SN - 0894-069X
KW - capacity allocation
KW - game theory
KW - nash equilibrium
KW - sequential game
ER -
TY - JOUR
TI - Dissecting the routing architecture of self-organizing networks
AU - Amorim, Marcelo
AU - Benbadis, Farid
AU - Fdida, Serge
AU - Sichitiu, Mihail L.
AU - Viniotis, Yannis
T2 - IEEE WIRELESS COMMUNICATIONS
AB - The proper operation of self-organizing networks (SONs) relies on the autonomous behavior of their individual nodes. Routing in such networks has been a challenging task since their conception, due to their nontraditional characteristics and design requirements. Although a large amount of routing architectures and protocols for SONs has been proposed, very little work has been done on the fundamental characteristics that make a routing strategy efficient for a particular network and/or design requirement. Contrary to traditional techniques where the routing architecture is structured as a single unit, we suggest in this article that routing be thought of as a combination of four main architectural components, namely, addressing, dissemination, discovery, and forwarding. This logical decomposition offers significant advantages from both the analysis and the design perspectives. We conclude from our observations that routing architectures should be scenario-driven, in the sense that the configuration parameters are not necessarily universally good for all application scenarios
DA - 2006/12//
PY - 2006/12//
DO - 10.1109/MWC.2006.275204
VL - 13
IS - 6
SP - 98-104
SN - 1558-0687
ER -
TY - JOUR
TI - Spatially distributed stochastic systems: Equation-free and equation-assisted preconditioned computations
AU - Qiao, Liang
AU - Erban, Radek
AU - Kelley, C. T.
AU - Kevrekidis, Ioannis G.
T2 - JOURNAL OF CHEMICAL PHYSICS
AB - Spatially distributed problems are often approximately modeled in terms of partial differential equations (PDEs) for appropriate coarse-grained quantities (e.g., concentrations). The derivation of accurate such PDEs starting from finer scale, atomistic models, and using suitable averaging is often a challenging task; approximate PDEs are typically obtained through mathematical closure procedures (e.g., mean field approximations). In this paper, we show how such approximate macroscopic PDEs can be exploited in constructing preconditioners to accelerate stochastic computations for spatially distributed particle-based process models. We illustrate how such preconditioning can improve the convergence of equation-free coarse-grained methods based on coarse timesteppers. Our model problem is a stochastic reaction-diffusion model capable of exhibiting Turing instabilities.
DA - 2006/11/28/
PY - 2006/11/28/
DO - 10.1063/1.2372492
VL - 125
IS - 20
SP -
SN - 1089-7690
ER -
TY - JOUR
TI - Production scheduling in a knitted fabric dyeing and finishing process
AU - Laoboonlur, P.
AU - Hodgson, Thom
AU - Thoney, K. A.
T2 - Journal of the Textile Institute
DA - 2006///
PY - 2006///
DO - 10.1533/joti.2005.0145
VL - 97
IS - 5
SP - 391–399
ER -
TY - JOUR
TI - Probabilistic robust linear parameter-varying control of an F-16 aircraft
AU - Lu, Bei
AU - Wu, Fen
T2 - JOURNAL OF GUIDANCE CONTROL AND DYNAMICS
AB - O PERATIONAL capability at high angles of attack, especially near and at post stall regimes, is critical for next generation fighter aircrafts and uninhabited aerial vehicles [1]. However, significantly large levels of modeling uncertainty are inevitably encountered inflight control design for those regimes. The sources of uncertainty include variations in mass, inertia, and center of gravity positions, uncertainty in the aerodynamic data, etc. [2]. The maneuverability at high angles of attack poses a challenging control problem that requires guaranteeing both robust stability and robust performance in the presence of large parameter variations. Traditional robust control techniques, like H1 and -synthesis, have been proven to be capable of producing robust uncertaintytolerant controllers for next generation aircrafts [2,3]. However, those techniques focus on deterministic worst-case robust analysis and synthesis, which often lead to overly conservative stability bound estimate and high control effort. Moreover, a large number of conventional deterministic problems in robustness analysis and synthesis are shown to be NP-hard. To reduce conservatism and computational complexity, one approach is to shift the meaning of robustness from its usual deterministic sense to a probabilistic one [4]. In contrast to traditional robust control techniques, only a probabilistic solution is given, and a certain risk-level should be accepted. However, such a system may be viewed as being practically robust from an engineering point of view. Algorithms derived in the probabilistic context are based on uncertainty randomization and usually called randomized algorithms, which may be divided into two families: methods based on statistical learning theory [5], and sequential methods based on subgradient iterations [6–8] or ellipsoid iterations [9,10]. The former can deal with nonconvex synthesis problems; however, it resorts to randomized search over the controller parameters to find a candidate solution. On the other hand, the sequential methods are formulated based on convex problems, thus avoiding the controller randomization issue [4]. The probabilistic robust control approach is still in the stage of algorithm development and improvement, and has not been explored in depth for flight control. The number of implementation of probabilistic techniques is therefore rather restricted. In the late 90s, Marrison and Stengel designed a linear quadratic regulator to control the nonlinear longitudinal dynamics of a hypersonic aircraft [11]. Recently, Wang and Stengel designed a robust flight control system for the high-incidence research model problem by combining stochastic robustness with nonlinear dynamic inversion [12]. Their work was based on statistical learning theory, and controllers were searched by using generic algorithms to minimize stochastic robustness cost functions. In our earlier paper, we applied an ellipsoid algorithm to design anH1 controller for a linearized F-16 longitudinal model [13]. Good stability and performance robustness have been achieved at the chosen flight condition. The motivation for this research is twofold. First, the probabilistic control design method for linear time-invariant plants in [13] is generalized to linear parameter-varying (LPV) systems. This generalization is very important because of the relevance of LPV systems to nonlinear systems. TheLPVcontrol synthesis condition is known to be formulated as a convex problemwith a set of parameterdependent linear matrix inequalities (LMIs) [14–16]. Second, the current state of the art does not allow accurate aerodynamicmodeling in the high angle of attack region. Because of its random nature, uncertainty in the aerodynamic data can be characterized using a statistical model, which can be handled effectively by the promising probabilistic robust control approach. Note that the study in this note focuses on the robustness issue with respect to the aerodynamic uncertainty at high angles of attack, and the results would be easily generalized to other parametric uncertainties, such as variations in mass and inertial properties. Because of the convex formulation of LPV control synthesis, the sequential method is more suitable for dealing with uncertainties and designing probabilistic robust LPV controllers. An ellipsoid algorithm with a stopping rule proposed by Oishi [10] is used to determine feasible solutions to LMI synthesis conditions. The paper is organized as follows. In Sec. II, the ellipsoid algorithm is presented, which either gives a probabilistic solution with high confidence or detects that there is no deterministic solution in an approximated sense. Section III first provides a brief overview of robust control problem of an uncertain LPV system, and then discusses the computational issues when the algorithm is applied to the robust LPV control problem. In Sec. IV, a robust LPV controller is designed for an F-16 aircraft with large aerodynamic uncertainty, and the robust performance is tested through nonlinear simulations. Finally, the paper concludes with a summary in Sec. V.
DA - 2006///
PY - 2006///
DO - 10.2514/1.22495
VL - 29
IS - 6
SP - 1454-1460
SN - 1533-3884
ER -
TY - JOUR
TI - A structured erythropoiesis model with nonlinear cell maturation velocity and hormone decay rate
AU - Ackleh, Azmy S.
AU - Deng, Keng
AU - Ito, Kazufumi
AU - Thibodeaux, Jeremy
T2 - MATHEMATICAL BIOSCIENCES
AB - We develop a quasilinear structured model that describes the regulation of erythropoiesis, the process in which red blood cells are developed. In our model, the maturation velocity of precursor cells is assumed to be a function of the erythropoietin hormone, and the decay rate of this hormone is assumed to be a function of the number of precursor cells, unlike other models which assume these parameters to be constants. Existence-uniqueness results are established and convergence of a finite difference approximation to the unique solution of the model is obtained. The finite difference scheme is then used to investigate the effects of these nonlinear parameters on the model dynamics. Our results show that a velocity of precursor cells maturation rate which is an increasing function of the hormone level and a decay rate of the hormone which is an increasing function of the number of precursor cells have a stabilizing effect on the dynamics of the model. While assuming that one parameter is a function and letting the other be a constant stabilizes the oscillations in the mature cells level, the effect is more significant when both parameters are taken to be functions. A study of robustness with respect to the forms of these functions and parameter sensitivity is also carried out.
DA - 2006/11//
PY - 2006/11//
DO - 10.1016/j.mbs.2006.08.004
VL - 204
IS - 1
SP - 21-48
SN - 1879-3134
KW - erythropoiesis
KW - structured model
KW - finite difference approximation
KW - existence-uniqueness
KW - behavior of solutions
ER -
TY - JOUR
TI - A semantics based approach to privacy languages
AU - Li, N.
AU - Yu, T.
AU - Anton, A.
T2 - Computer Systems Science and Engineering
DA - 2006///
PY - 2006///
VL - 21
IS - 5
SP - 339-352
ER -
TY - JOUR
TI - Special issue on accurate solution of eigenvalue problems
AU - Ipsen, Ilse C. F.
T2 - SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS
DA - 2006///
PY - 2006///
DO - 10.1137/sjmael0000280000040000ix000001
VL - 28
IS - 4
SP - IX-IX
SN - 0895-4798
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-35348933724&partnerID=MN8TOARS
ER -
TY - BOOK
TI - Google's PageRank and beyond: The science of search engine rankings
AU - Langville, A. N.
AU - Meyer, C. D.
AB - Why doesn't your home page appear on the first page of search results, even when you query your own name? How do other web pages always appear at the top? What creates these powerful rankings? And how? The first book ever about the science of web page rankings, Google's PageRank and Beyond supplies the answers to these and other questions and more. The book serves two very different audiences: the curious science reader and the technical computational reader. The chapters build in mathematical sophistication, so that the first five are accessible to the general academic reader. While other chapters are much more mathematical in nature, each one contains something for both audiences. For example, the authors include entertaining asides such as how search engines make money and how the Great Firewall of China influences research. The book includes an extensive background chapter designed to help readers learn more about the mathematics of search engines, and it contains several MATLAB codes and links to sample web data sets. The philosophy throughout is to encourage readers to experiment with the ideas and algorithms in the text. Any business seriously interested in improving its rankings in the major search engines can benefit from the clear examples, sample code, and list of resources provided. Many illustrative examples and entertaining asides MATLAB code Accessible and informal style Complete and self-contained section for mathematics review
CN - TK5101.884 .L36 2006
DA - 2006///
PY - 2006///
DO - 10.1515/9781400830329
PB - Princeton, NJ: Princeton University Press
SN - 0691122024
ER -
TY - JOUR
TI - Updating Markov chains with an eye on Google's PageRank
AU - Langville, AN
AU - Meyer, CD
T2 - SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS
AB - An iterative algorithm based on aggregation/disaggregation principles is presented for updating the stationary distribution of a finite homogeneous irreducible Markov chain. The focus is on large-scale problems of the kind that are characterized by Google's PageRank application, but the algorithm is shown to work well in general contexts. The algorithm is flexible in that it allows for changes to the transition probabilities as well as for the creation or deletion of states. In addition to establishing the rate of convergence, it is proven that the algorithm is globally convergent. Results of numerical experiments are presented.
DA - 2006///
PY - 2006///
DO - 10.1137/040619028
VL - 27
IS - 4
SP - 968-987
SN - 1095-7162
KW - Markov chains
KW - updating
KW - stationary vector
KW - PageRank
KW - stochastic complementation
KW - aggregation/disaggregation
KW - Google
ER -
TY - JOUR
TI - Reduced order control based on approximate inertial manifolds
AU - Ito, Kazufumi
AU - Kunisch, Karl
T2 - LINEAR ALGEBRA AND ITS APPLICATIONS
AB - A reduced-order method based on approximate inertial manifolds is applied to optimal control problems in infinite-dimensional state spaces. A detailed analysis of the method is given for the linear quadratic regulator problem. The method can also be applied to higher-order control systems with an appropriate decomposition of the state space in terms of slow and fast exponential decay.
DA - 2006/6/1/
PY - 2006/6/1/
DO - 10.1016/j.laa.2004.10.019
VL - 415
IS - 2-3
SP - 531-541
SN - 1873-1856
KW - reduced order method
KW - approximate inertial manifold
KW - LQR-problern
KW - decomposition of state space
KW - infinite-dimensional system
ER -
TY - JOUR
TI - Receding horizon control with incomplete observations
AU - Ito, K
AU - Kunisch, K
T2 - SIAM JOURNAL ON CONTROL AND OPTIMIZATION
AB - To overcome the difficulties related to the computational requirements for solving the optimality systems for optimal control problems on long time horizons, receding horizon techniques provide an important alternative. Rather than finding the optimal solution, a suboptimal control is obtained which achieves the design objective with significantly less computational effort. Moreover, the obtained control can be interpreted as a state feedback control. In this work we continue our analysis of receding horizon strategies, considering the situation when only partial state observations are available. The receding horizon strategy is combined with a state estimator framework. A linearquadratic Gaussian design based on a linearization procedure is proposed and its asymptotic performance is analyzed for systems with nonlinear dynamics. Numerical examples validate the proposed methodology.
DA - 2006///
PY - 2006///
DO - 10.1137/S0363012903437988
VL - 45
IS - 1
SP - 207-225
SN - 1095-7138
KW - receding horizon control
KW - incomplete observations
KW - dynamic compensator
ER -
TY - JOUR
TI - Predicting Shine-Dalgarno sequence locations exposes genome annotation errors
AU - Starmer, J.
AU - Stomp, A.
AU - Vouk, M.
AU - Bitzer, D.
T2 - PLOS COMPUTATIONAL BIOLOGY
AB - In prokaryotes, Shine–Dalgarno (SD) sequences, nucleotides upstream from start codons on messenger RNAs (mRNAs) that are complementary to ribosomal RNA (rRNA), facilitate the initiation of protein synthesis. The location of SD sequences relative to start codons and the stability of the hybridization between the mRNA and the rRNA correlate with the rate of synthesis. Thus, accurate characterization of SD sequences enhances our understanding of how an organism's transcriptome relates to its cellular proteome. We implemented the Individual Nearest Neighbor Hydrogen Bond model for oligo–oligo hybridization and created a new metric, relative spacing (RS), to identify both the location and the hybridization potential of SD sequences by simulating the binding between mRNAs and single-stranded 16S rRNA 3′ tails. In 18 prokaryote genomes, we identified 2,420 genes out of 58,550 where the strongest binding in the translation initiation region included the start codon, deviating from the expected location for the SD sequence of five to ten bases upstream. We designated these as RS+1 genes. Additional analysis uncovered an unusual bias of the start codon in that the majority of the RS+1 genes used GUG, not AUG. Furthermore, of the 624 RS+1 genes whose SD sequence was associated with a free energy release of less than −8.4 kcal/mol (strong RS+1 genes), 384 were within 12 nucleotides upstream of in-frame initiation codons. The most likely explanation for the unexpected location of the SD sequence for these 384 genes is mis-annotation of the start codon. In this way, the new RS metric provides an improved method for gene sequence annotation. The remaining strong RS+1 genes appear to have their SD sequences in an unexpected location that includes the start codon. Thus, our RS metric provides a new way to explore the role of rRNA–mRNA nucleotide hybridization in translation initiation.
DA - 2006/5//
PY - 2006/5//
DO - 10.1371/journal.pcbi.0020057
VL - 2
IS - 5
SP - 454-466
SN - 1553-7358
ER -
TY - JOUR
TI - Model development for atomic force microscope stage mechanisms
AU - Smith, Ralph C.
AU - Hatch, Andrew G.
AU - De, Tathagata
AU - Salapaka, Murti V.
AU - Del Rosario, Ricardo C. H.
AU - Raye, Julie K.
T2 - SIAM JOURNAL ON APPLIED MATHEMATICS
AB - In this paper, we develop nonlinear constitutive equations and resulting system models quantifying the nonlinear and hysteretic field‐displacement relations inherent to lead zirconate titanate (PZT) devices employed in atomic force microscope stage mechanisms. We focus specifically on PZT rods utilizing $d_{33}$ motion and PZT shells driven in $d_{31}$ regimes, but the modeling framework is sufficiently general to accommodate a variety of drive geometries. In the first step of the model development, lattice‐level energy relations are combined with stochastic homogenization techniques to construct nonlinear constitutive relations which accommodate the hysteresis inherent to ferroelectric compounds. Second, these constitutive relations are employed in classical rod and shell relations to construct system models appropriate for presently employed nanopositioner designs. The capability of the models for quantifying the frequency‐dependent hysteresis inherent to the PZT stages is illustrated through comparison with experimental data.
DA - 2006///
PY - 2006///
DO - 10.1137/05063307X
VL - 66
IS - 6
SP - 1998-2026
SN - 1095-712X
KW - atomic force microscope
KW - hysteresis model
KW - dynamics
ER -
TY - JOUR
TI - Locally invertible multivariate polynomial matrices
AU - Lobo, R. G.
AU - Bitzer, D. L.
AU - Vouk, M. A.
T2 - Lecture Notes in Computer Science
DA - 2006///
PY - 2006///
IS - 3969
SP - 427-441
ER -
TY - JOUR
TI - Conjunctive use of models to design cost-effective ozone control strategies
AU - Fu, Joshua S.
AU - Brill, E. Downey, III
AU - Ranjithan, S. Ranji
T2 - JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION
AB - The management of tropospheric ozone (O3) is particularly difficult. The formulation of emission control strategies requires considerable information including: (1) emission inventories, (2) available control technologies, (3) meteorological data for critical design episodes, and (4) computer models that simulate atmospheric transport and chemistry. The simultaneous consideration of this information during control strategy design can be exceedingly difficult for a decision-maker. Traditional management approaches do not explicitly address cost minimization. This study presents a new approach for designing air quality management strategies; a simple air quality model is used conjunctively with a complex air quality model to obtain low-cost management strategies. A simple air quality model is used to identify potentially good solutions, and two heuristic methods are used to identify cost-effective control strategies using only a small number of simple air quality model simulations. Subsequently, the resulting strategies are verified and refined using a complex air quality model. The use of this approach may greatly reduce the number of complex air quality model runs that are required. An important component of this heuristic design framework is the use of the simple air quality model as a screening and exploratory tool. To achieve similar results with the simple and complex air
DA - 2006/6//
PY - 2006/6//
DO - 10.1080/10473289.2006.10464492
VL - 56
IS - 6
SP - 800-809
SN - 2162-2906
ER -
TY - CHAP
TI - Characterization of the burst aggregation process in optical burst switching
AU - Mountrouidou, X.
AU - Perros, H. G.
T2 - Networking 2006. Networking Technologies, Services, and Protocols; Performance of Computer and Communication Networks; Mobile and Wireless Communications Systems: 5th International IFIP-TC6 Networking Conference, Coimbra, Portugal, May 15-19, 2006. Proceedings (Lecture notes in computer science; 3976)
AB - We describe an analytic approach for the calculation of the departure process from a burst ggregation algorithm that uses both a timer and maximum/minimum burst size. The arrival process of packets is assumed to be Poisson or bursty modelled by an Interrupted Poisson Process (IPP). The analytic results are approximate and validation against simulation data showed that they have good accuracy.
PY - 2006///
DO - 10.1007/11753810_63
VL - 3976
SP - 752-764
PB - Berlin; New York: Springer
ER -
TY - JOUR
TI - Answering queries using materialized views with minimum size
AU - Chirkova, Rada
AU - Li, Chen
AU - Li, Jia
T2 - VLDB JOURNAL
AB - In this paper, we study the following problem. Given a database and a set of queries, we want to find a set of views that can compute the answers to the queries, such that the amount of space, in bytes, required to store the viewset is minimum on the given database. (We also handle problem instances where the input has a set of database instances, as described by an oracle that returns the sizes of view relations for given view definitions.) This problem is important for applications such as distributed databases, data warehousing, and data integration. We explore the decidability and complexity of the problem for workloads of conjunctive queries. We show that results differ significantly depending on whether the workload queries have self-joins. Further, for queries without self-joins we describe a very compact search space of views, which contains all views in at least one optimal viewset. We present techniques for finding a minimum-size viewset for a single query without self-joins by using the shape of the query and its constraints, and validate the approach by extensive experiments.
DA - 2006/9//
PY - 2006/9//
DO - 10.1007/s00778-005-0162-8
VL - 15
IS - 3
SP - 191-210
SN - 0949-877X
KW - views
KW - data warehouses
KW - minimum-size viewsets
KW - distributed systems
ER -
TY - JOUR
TI - Additive scaling and the DIRECT algorithm
AU - Finkel, D. E.
AU - Kelley, C. T.
T2 - JOURNAL OF GLOBAL OPTIMIZATION
DA - 2006/12//
PY - 2006/12//
DO - 10.1007/s10898-006-9029-9
VL - 36
IS - 4
SP - 597-608
SN - 0925-5001
KW - DIRECT
KW - global optimization
KW - additive scaling
ER -
TY - JOUR
TI - A homogenized energy model for the direct magnetomechanical effect
AU - Smith, Ralph C.
AU - Dapino, Marcelo J.
T2 - IEEE TRANSACTIONS ON MAGNETICS
AB - This paper focuses on the development of a homogenized energy model which quantifies certain facets of the direct magnetomechanical effect. In the first step of the development, Gibbs energy analysis at the lattice level is combined with Boltzmann principles to quantify the local average magnetization as a function of input fields and stresses. A macroscopic magnetization model, which incorporates the effects of polycrystallinity, material nonhomogeneities, stress-dependent interaction fields, and stress-dependent coercive behavior, is constructed through stochastic homogenization techniques based on the tenet that local coercive and interaction fields are manifestations of underlying distributions rather than constants. The resulting framework incorporates previous ferromagnetic hysteresis theory as a special case in the absence of applied stresses. Attributes of the framework are illustrated through comparison with previously published steel and iron data
DA - 2006/8//
PY - 2006/8//
DO - 10.1109/TMAG.2006.875705
VL - 42
IS - 8
SP - 1944-1957
SN - 0018-9464
KW - ferromagnetic materials
KW - magnetic hysteresis
KW - magnetornechanical effects
KW - magnetostrictive devices
KW - modeling
KW - nonlinear magnetics
ER -
TY - JOUR
TI - A cost-minimization algorithm for fast location tracking in mobile wireless networks
AU - Wang, Wenye
AU - Xue, Guoliang
T2 - COMPUTER NETWORKS
AB - Location tracking is one of the most important issues in providing real-time applications over wireless networks due to its effect to quality of service (QoS), such as end-to-end delay, bandwidth utilization, and connection dropping probability. In this paper, we study cost minimization for locating mobile users under delay constraints in mobile wireless networks. Specifically, a new location tracking algorithm is developed to determine the position of mobile terminals under delay constraints, while minimizing the average locating cost based on a unimodal property. We demonstrate that the new algorithm not only results in minimum locating cost, but also has a lower computational complexity compared to existing algorithms. Furthermore, detailed searching procedures are discussed under both deterministic and statistic delay bounds. Numerical results for a variety of location probability distributions show that our algorithm compares favorably with existing algorithms.
DA - 2006/10/18/
PY - 2006/10/18/
DO - 10.1016/j.comnet.2005.09.035
VL - 50
IS - 15
SP - 2713-2726
SN - 1872-7069
KW - wireless networks
KW - location tracking
KW - partition
KW - optimization
ER -
TY - JOUR
TI - Twins: A dual addressing space representation for self-organizing networks
AU - Carneiro Viana, Aline
AU - Amorim, Marcelo
AU - Viniotis, Yannis
AU - Fdida, Serge
AU - Rezende, Jose
T2 - IEEE TRANSACTIONS ON PARALLEL AND DISTRIBUTED SYSTEMS
AB - As the size of mobile self-organizing networks increases, the efficiency of location services must increase as well so that addressing/routing scalability does not become an issue. In this paper, we propose a novel architecture, called Twins, tailored for self-organizing networks. Twins architecture involves addressing and locating nodes in large networks, forwarding packets between them, and managing in the presence of mobility/topology changes. Twins defines a logical multidimensional space for addressing and forwarding, while location service and management operations make use of a one-dimensional space. To improve scalability and performance, forwarding is hop-by-hop with greedy next-hop choice and the location service uses a rendezvous paradigm to distribute information among nodes. In this paper, we describe the Twins architecture and present a performance evaluation to assess scalability, fairness in the overhead distribution among nodes, and routing robustness.
DA - 2006/12//
PY - 2006/12//
DO - 10.1109/TPDS.2006.179
VL - 17
IS - 12
SP - 1468-1481
SN - 1558-2183
KW - distributed networks
KW - network topology
KW - wireless communication
KW - protocol architecture
KW - routing protocols
ER -
TY - BOOK
TI - The immersed interface method: Numerical solutions of PDEs involving interfaces and irregular domains
AU - Li, Zhilin
AU - Ito, K.
CN - QA374 .L42 2006
DA - 2006///
PY - 2006///
DO - 10.1137/1.9780898717464
PB - Philadelphia: SIAM, Society for Industrial and Applied Mathematics
SN - 0898716098
ER -
TY - JOUR
TI - The Picard iteration and its application
AU - Chen, X
AU - Hartwig, RE
T2 - LINEAR & MULTILINEAR ALGEBRA
AB - The convergence behavior of the Picard iteration Xk+1=AXk+B and the weighted case Yk=Xk/bk is investigated. It is shown that the convergence of both these iterations is related to the so-called effective spectrum of A with respect to some matrix. As an application of our convergence results we discuss the convergence behavior of a sequence of scaled triangular matrices {DNTN }.
DA - 2006/9//
PY - 2006/9//
DO - 10.1080/03081080500209703
VL - 54
IS - 5
SP - 329-341
SN - 0308-1087
KW - Picard iteration
KW - Schur complement
KW - path condition
ER -
TY - JOUR
TI - Supply management's evolution: key skill sets for the supply manager of the future
AU - Giunipero, Larry
AU - Handfield, Robert B.
AU - Eltantawy, Reham
T2 - INTERNATIONAL JOURNAL OF OPERATIONS & PRODUCTION MANAGEMENT
AB - Purpose In the last decade there have been dramatic impacts on, and changes within, the field of purchasing/supply management. Given supply management's new strategic role, this research seeks to examine the key skills and knowledge necessary for firms to improve in order to maximize the purchasing function's contribution to the organization. The research also aims to identifies the major shifts in supply management that have occurred in the last decade. Design/methodology/approach A qualitative study was conducted with a series of focus group meetings with 54 executives across the USA in order to construct theoretical relationships with which to develop a grounded theory of supply management skills evolution in a changing business environment. Findings The implications from this research indicate that supply management professionals will assume a more strategic role in the future. The data indicate that there are strong trends underlying this movement. These include the need for building strategic relationships, focusing on total cost and strategic cost reduction, yet collaborating and integrating with suppliers. While in the past these efforts may have appeared to be contradictory, with proper strategic planning they can be complementary. Originality/value Supply managers of the future need to acquire strategic skills that add value and enable effective alignment with key business functions at a senior decision‐making level. Additional research is needed in the area to determine how best to recruit and train managers in these skills to move forward.
DA - 2006///
PY - 2006///
DO - 10.1108/01443570610672257
VL - 26
IS - 7
SP - 822-844
SN - 1758-6593
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33745317995&partnerID=MN8TOARS
KW - skills
KW - knowledge management
KW - supply
KW - delphi method
KW - strategic management
KW - supply chain management
ER -
TY - JOUR
TI - Preconditioned iterative methods on sparse subspaces
AU - Ito, Kazufumi
AU - Toivanen, Jari
T2 - APPLIED MATHEMATICS LETTERS
AB - When some rows of the system matrix and a preconditioner coincide, preconditioned iterations can be reduced to a sparse subspace. Taking advantage of this property can lead to considerable memory and computational savings. This is particularly useful with the GMRES method. We consider the iterative solution of a discretized partial differential equation on this sparse subspace. With a domain decomposition method and a fictitious domain method the subspace corresponds a small neighborhood of an interface. As numerical examples we solve the Helmholtz equation using a fictitious domain method and an elliptic equation with a jump in the diffusion coefficient using a separable preconditioner.
DA - 2006/11//
PY - 2006/11//
DO - 10.1016/j.aml.2005.11.027
VL - 19
IS - 11
SP - 1191-1197
SN - 0893-9659
KW - subspace iteration
KW - preconditioning
KW - Krylov subspace method
KW - domain decomposition method
KW - fictitious domain method
KW - interface problem
ER -
TY - JOUR
TI - On the value of static analysis for fault detection in software
AU - Zheng, J
AU - Williams, L
AU - Nagappan, N
AU - Snipes, W
AU - Hudepohl, JP
AU - Vouk, MA
T2 - IEEE TRANSACTIONS ON SOFTWARE ENGINEERING
AB - No single software fault-detection technique is capable of addressing all fault-detection concerns. Similarly to software reviews and testing, static analysis tools (or automated static analysis) can be used to remove defects prior to release of a software product. To determine to what extent automated static analysis can help in the economic production of a high-quality product, we have analyzed static analysis faults and test and customer-reported failures for three large-scale industrial software systems developed at Nortel Networks. The data indicate that automated static analysis is an affordable means of software fault detection. Using the orthogonal defect classification scheme, we found that automated static analysis is effective at identifying assignment and checking faults, allowing the later software production phases to focus on more complex, functional, and algorithmic faults. A majority of the defects found by automated static analysis appear to be produced by a few key types of programmer errors and some of these types have the potential to cause security vulnerabilities. Statistical analysis results indicate the number of automated static analysis faults can be effective for identifying problem modules. Our results indicate static analysis tools are complementary to other fault-detection techniques for the economic production of a high-quality software product.
DA - 2006/4//
PY - 2006/4//
DO - 10.1109/TSE.2006.38
VL - 32
IS - 4
SP - 240-253
SN - 1939-3520
KW - code inspections
KW - walkthroughs
ER -
TY - JOUR
TI - Note on a linear difference equation
AU - Hartwig, RE
T2 - AMERICAN MATHEMATICAL MONTHLY
DA - 2006/3//
PY - 2006/3//
DO - 10.2307/27641892
VL - 113
IS - 3
SP - 250-256
SN - 0002-9890
ER -
TY - BOOK
TI - Modeling and simulation in Scilab/Scicos
AU - Campbell, S.
AU - Chancelier, J.-P.
AU - Nikoukhah, R.
DA - 2006///
PY - 2006///
PB - New York: Springer
SN - 0387278028
ER -
TY - JOUR
TI - Material surface design to counter electromagnetic interrogation of targets
AU - Banks, HT
AU - Ito, K
AU - Kepler, GM
AU - Toivanen, JA
T2 - SIAM JOURNAL ON APPLIED MATHEMATICS
AB - Utilization of controllable ferromagnetic layers coating a conducting object to provide an attenuation capability against electromagnetic interrogation is discussed. The problem is formulated as a differential game and/or a robust optimization. The scattered field due to interrogation can be attenuated with the assumption of an uncertainty in the interrogation wave numbers. The controllable layer composed of ferromagnetic materials [H. How and C. Vittoria, Implementation of Microwave Active Nulling, private communication; H. How and C. Vittoria, IEEE Trans. Microwave Theory Tech., 52 (2004), pp. 2177-2182] is incorporated in a mathematical formulation based on the time-harmonic Maxwell equation. Fresnel's law for the reflectance index is extended to the electromagnetic propagation in anisotropic composite layers of ferromagnetic and electronic devices and is used to demonstrate feasibility of control of reflections. Our methodology is also tested for a nonplanar geometry of the conducting object (an NACA airfoil) in which we report our findings in the form of reduced radar cross sections (RCS)\@.
DA - 2006///
PY - 2006///
DO - 10.1137/040621430
VL - 66
IS - 3
SP - 1027-1049
SN - 1095-712X
KW - electromagnetic
KW - inverse scattering
KW - attenuation
ER -
TY - JOUR
TI - Integrated modeling of information and physical flows in transportation systems
AU - Cetin, Mecit
AU - List, George F.
T2 - TRANSPORTATION RESEARCH PART C-EMERGING TECHNOLOGIES
AB - Modeling transportation systems operations in large part involves an understanding of how physical entities (i.e., vehicles) move and interact with each other in the system. Transportation systems that are integrated with information technologies involve flow of information besides the flow of physical entities. In some cases, a unified modeling approach that considers both flows is needed to create an accurate model for system operations. This paper highlights the significance of such a modeling approach that involves an explicit representation of information flow attributes (e.g., response time and information delay). Several small-scale queuing models are developed to illustrate the importance of incorporating information flow related attributes into the models of transportation systems operations. In each example system, two scenarios are considered: modeling the given system with or without explicitly representing the information flow. Comparison of performance statistics is made between these two scenarios. It is found that ignoring information flows may lead to significant inaccuracies in the estimates of the system performance.
DA - 2006/4//
PY - 2006/4//
DO - 10.1016/j.trc.2006.06.003
VL - 14
IS - 2
SP - 139-156
SN - 0968-090X
KW - intelligent transportation systems
KW - information flow
KW - performance modeling
KW - correlation
ER -
TY - JOUR
TI - Efficient implementation algorithms for homogenized energy models
AU - Braun, Thomas R.
AU - Smith, Ralph C.
T2 - CONTINUUM MECHANICS AND THERMODYNAMICS
AB - The homogenized energy framework quantifying ferroelectric and ferromagnetic hysteresis is increasingly used for comprehensive material characterization and model-based control design. For operating regimes in which thermal relaxation mechanisms and stress-dependencies are negligible, existing algorithms are sufficiently efficient to permit device optimization and the potential for real-time control implementation. In this paper, we develop algorithms employing lookup tables which permit the high speed implementation of formulations which incorporate relaxation mechanisms and electromechanical coupling. Aspects of the algorithms are illustrated through comparison with experimental data.
DA - 2006/9//
PY - 2006/9//
DO - 10.1007/s00161-006-0015-8
VL - 18
IS - 3-4
SP - 137-155
SN - 0935-1175
ER -
TY - JOUR
TI - Convergence analysis of a PageRank updating algorithm by Langville and Meyer
AU - Ipsen, ICF
AU - Kirkland, S
T2 - SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS
AB - The PageRank updating algorithm proposed by Langville and Meyer is a special case of an iterative aggregation/disaggregation (SIAD) method for computing stationary distributions of very large Markov chains. It is designed, in particular, to speed up the determination of PageRank, which is used by the search engine Google in the ranking of web pages. In this paper the convergence, in exact arithmetic, of the SIAD method is analyzed. The SIAD method is expressed as the power method preconditioned by a partial LU factorization. This leads to a simple derivation of the asymptotic convergence rate of the SIAD method. It is known that the power method applied to the Google matrix always converges, and we show that the asymptotic convergence rate of the SIAD method is at least as good as that of the power method. Furthermore, by exploiting the hyperlink structure of the web it can be shown that the asymptotic convergence rate of the SIAD method applied to the Google matrix can be made strictly faster than that of the power method.
DA - 2006///
PY - 2006///
DO - 10.1137/S0895479804439808
VL - 27
IS - 4
SP - 952-967
SN - 1095-7162
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33646455491&partnerID=MN8TOARS
KW - Google
KW - PageRank
KW - Markov chain
KW - power method
KW - stochastic complement
KW - aggregation/disaggregation
ER -
TY - JOUR
TI - Construction and experimental implementation of a model-based inverse filter to attenuate hysteresis in ferroelectric transducers
AU - Hatch, Andrew G.
AU - Smith, Ralph C.
AU - De, Tathagata
AU - Salapaka, Murti V.
T2 - IEEE TRANSACTIONS ON CONTROL SYSTEMS TECHNOLOGY
AB - Hysteresis and constitutive nonlinearities are inherent properties of ferroelectric transducer materials due to the noncentrosymmetric nature of the compounds. In certain regimes, these effects can be mitigated through restricted input fields, charge- or current-controlled amplifiers, or feedback designs. For general operating conditions, however, these properties must be accommodated in models, transducer designs, and model-based control algorithms to achieve the novel capabilities provided by the compounds. In this paper, we illustrate the construction of inverse filters, based on homogenized energy models, which can be used to approximately linearize the piezoceramic transducer behavior for linear design and control implementation. Attributes of the inverse filters are illustrated through numerical examples and experimental open loop control implementation for an atomic force microscope stage
DA - 2006/11//
PY - 2006/11//
DO - 10.1109/TCST.2006.883195
VL - 14
IS - 6
SP - 1058-1069
SN - 1558-0865
KW - atomic force microscopy (AFM)
KW - control systems
KW - dielectric hysteresis
KW - ferroelectric devices
KW - modeling
ER -
TY - JOUR
TI - An augmented approach for the pressure boundary condition in a Stokes flow
AU - Li, Z. L.
AU - Wan, X. H.
AU - Ito, K.
AU - Lubkin, S. R.
T2 - Communications in Computational Physics
DA - 2006///
PY - 2006///
VL - 1
IS - 5
SP - 874-885
ER -
TY - JOUR
TI - An adaptive cyberinfrastructure for threat management in urban water distribution systems
AU - Mahinthakumar, K.
AU - Von Laszewski, G.
AU - Ranjithan, R.
AU - Brill, D.
AU - Uber, J.
AU - Harrison, K.
AU - Sreepathi, S.
AU - Zechman, E.
T2 - Computational Science - ICCS 2006, Pt. 3, Proceedings
AB - Threat management in drinking water distribution systems involves real-time characterization of any contaminant source and plume, design of control strategies, and design of incremental data sampling schedules. This requires dynamic integration of time-varying measurements along with analytical modules that include simulation models, adaptive sampling procedures, and optimization methods. These modules are compute-intensive, requiring multi-level parallel processing via computer clusters. Since real-time responses are critical, the computational needs must also be adaptively matched with available resources. This requires a software system to facilitate this integration via a high-performance computing architecture such that the measurement system, the analytical modules and the computing resources can mutually adapt and steer each other. This paper describes the development of such an adaptive cyberinfrastructure system facilitated by a dynamic workflow design.
DA - 2006///
PY - 2006///
DO - 10.1007/11758532_54
VL - 3993
SP - 401-408
ER -
TY - JOUR
TI - A wavelet-based spectral procedure for steady-state simulation analysis
AU - Lada, Emily K.
AU - Wilson, James R.
T2 - EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
AB - We develop WASSP, a wavelet-based spectral method for steady-state simulation analysis. First WASSP determines a batch size and a warm-up period beyond which the computed batch means form an approximately stationary Gaussian process. Next WASSP computes the discrete wavelet transform of the bias-corrected log-smoothed-periodogram of the batch means, using a soft-thresholding scheme to denoise the estimated wavelet coefficients. Then taking the inverse discrete wavelet transform of the thresholded wavelet coefficients, WASSP computes estimators of the batch means log-spectrum and the steady-state variance parameter (i.e., the sum of covariances at all lags) for the original (unbatched) process. Finally by combining the latter estimator with the batch means grand average, WASSP provides a sequential procedure for constructing a confidence interval on the steady-state mean that satisfies user-specified requirements concerning absolute or relative precision as well as coverage probability. An experimental performance evaluation demonstrates WASSP’s effectiveness compared with other simulation analysis methods.
DA - 2006/11/1/
PY - 2006/11/1/
DO - 10.1016/j.ejor.2005.04.025
VL - 174
IS - 3
SP - 1769-1801
SN - 0377-2217
KW - simulation
KW - steady-state analysis
KW - spectral method
KW - time series
KW - wavelet analysis
ER -
TY - JOUR
TI - A state-dependent Riccati equation-based estimator approach for HIV feedback control
AU - Banks, HT
AU - Kwon, HD
AU - Toivanen, JA
AU - Tran, HT
T2 - OPTIMAL CONTROL APPLICATIONS & METHODS
AB - We consider optimal dynamic multidrug therapies for human immunodeficiency virus (HIV) type 1 infection. In this context, we describe an optimal tracking problem attempting to drive the states of the system to a stationary state in which the viral load is low and the immune response is strong. We consider optimal feedback control with full-state as well as with partial-state measurements. In the case of partial-state measurement, a state estimator is constructed based on viral load and T-cell count measurements. We demonstrate by numerical simulations that by anticipation of and response to the disease progression, the dynamic multidrug strategy reduces the viral load, increases the CD4+ T-cell count and improves the immune response. Copyright © 2006 John Wiley & Sons, Ltd.
DA - 2006///
PY - 2006///
DO - 10.1002/oca.773
VL - 27
IS - 2
SP - 93-121
SN - 1099-1514
KW - multidrug therapies
KW - feedback control
KW - estimator
KW - HIV model
KW - SDRE
ER -
TY - JOUR
TI - A reordering for the PageRank problem
AU - Langville, AN
AU - Meyer, CD
T2 - SIAM JOURNAL ON SCIENTIFIC COMPUTING
AB - We describe a reordering particularly suited to the PageRank problem, which reduces the computation of the PageRank vector to that of solving a much smaller system and then using forward substitution to get the full solution vector. We compare the theoretical rates of convergence of the original PageRank algorithm to that of the new reordered PageRank algorithm, showing that the new algorithm can do no worse than the original algorithm. We present results of an experimental comparison on five datasets, which demonstrate that the reordered PageRank algorithm can provide a speedup of as much as a factor of 6. We also note potential additional benefits that result from the proposed reordering.
DA - 2006///
PY - 2006///
DO - 10.1137/040607551
VL - 27
IS - 6
SP - 2112-2120
SN - 1095-7197
KW - Markov chains
KW - PageRank
KW - reorderings
KW - power method
KW - convergence
KW - stationary vector
KW - dangling nodes
ER -
TY - JOUR
TI - A homogenization model for laser beam-induced current imaging and detection of non-uniformities in semiconductor arrays
AU - Fang, Weifu
AU - Ito, Kazufumi
AU - Redfern, David A.
T2 - JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS
AB - We present an approximate model for laser beam-induced current (LBIC) imaging of arrays of semiconductor devices based on homogenization. LBIC is a non-destructive technique useful for the characterization and quality control of semiconductor focal plane arrays, a key component in modern imaging systems. The model provides not only an efficient alternative for LBIC image simulation of large uniform arrays, but also an effective method for detection of non-uniformities among arrays. Numerical examples are presented to illustrate the effectiveness of this method in detecting array non-uniformities due to variations in dislocation/size or doping level among p–n junction diodes.
DA - 2006/10/1/
PY - 2006/10/1/
DO - 10.1016/j.cam.2005.08.007
VL - 194
IS - 2
SP - 395-408
SN - 1879-1778
KW - semiconductor arrays
KW - laser beam-induced current
KW - LBIC
KW - homogenization
KW - inverse problems
ER -
TY - JOUR
TI - Traffic grooming in path, star, and tree networks: Complexity, bounds, and algorithms
AU - Huang, Shu
AU - Dutta, Rudra
AU - Rouskas, George N.
T2 - IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS
DA - 2006/4//
PY - 2006/4//
DO - 10.1109/jsac-ocn.2006.04006
VL - 24
IS - 4
SP - 66-82
SN - 1558-0008
KW - optical
KW - networks
KW - networking
KW - traffic grooming
KW - virtual topology
ER -
TY - JOUR
TI - The state of JOM: An outgoing editor's (retro)spective
AU - Handfield, Robert
T2 - JOURNAL OF OPERATIONS MANAGEMENT
DA - 2006/9//
PY - 2006/9//
DO - 10.1016/j.jom.2006.07.002
VL - 24
IS - 5
SP - 417-420
SN - 0272-6963
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33747891682&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Performance evaluation of recent procedures for steady-state simulation analysis
AU - Lada, Emily K.
AU - Steiger, Natalie M.
AU - Wilson, James R.
T2 - IIE TRANSACTIONS
AB - The performance of the batch-means procedure ASAP3 and the spectral procedure WASSP is evaluated on test problems with characteristics typical of practical applications of steady-state simulation analysis procedures. ASAP3 and WASSP are sequential procedures designed to produce a confidence-interval estimator for the mean response that satisfies user-specified half-length and coverage-probability requirements. ASAP3 is based on an inverse Cornish-Fisher expansion for the classical batch-means t-ratio, whereas WASSP is based on a wavelet estimator of the batch-means power spectrum. Regarding closeness of the empirical coverage probability and average half-length of the delivered confidence intervals to their respective nominal levels, both procedures compared favorably with the Law-Carson procedure and the original ASAP algorithm. Regarding the average sample sizes required for decreasing levels of maximum confidence-interval half-length, ASAP3 and WASSP exhibited reasonable efficiency in the test problems.
DA - 2006/9//
PY - 2006/9//
DO - 10.1080/07408170600735520
VL - 38
IS - 9
SP - 711-727
SN - 1545-8830
ER -
TY - JOUR
TI - Parabolic variational inequalities: The Lagrange multiplier approach
AU - Ito, K
AU - Kunisch, K
T2 - JOURNAL DE MATHEMATIQUES PURES ET APPLIQUEES
AB - Parabolic variational inequalities are discussed and existence and uniqueness of strong as well as weak solutions are established. Our approach is based on a Lagrange multiplier treatment. Existence is obtained as the unique asymptotic limit of solutions to a family of appropriately regularized nonlinear parabolic equations. Two regularization techniques are presented resulting in feasible and unfeasible approximations respectively. Monotonicity results of the regularized solutions and convergence rate estimate are established. The results are applied to the Black–Scholes model for American options. The case of the bilateral constraints is also treated. Numerical results for the Black–Scholes model are presented and prove the practical efficiency of our results. Des inégalités variationnelles paraboliques sont discutées et l'existence et l'unicité des solutions fortes faibles sont établies. Notre approche des solutions utilise une méthode de multiplicateur de Lagrange. L'existence est obtenue comme limite asymptotique unique des solutions à une famille d'équations paraboliques non linéaires convenablement régularisées. Deux techniques de régularisation sont présentées ayant pour résultat des approximations acceptées ou rejetées. Des résultats de monotonie des solutions régularisées et d'évaluation de taux de convergence sont établis. Les résultats sont appliqués au modèle Black–Scholes pour des options américaines. Le cas des contraintes bilatérales est également traité. Des résultats numériques pour le modèle Black–Scholes sont présentés et prouvent l'efficacité pratique de nos techniques.
DA - 2006/3//
PY - 2006/3//
DO - 10.1016/j.matpur.2005.08.005
VL - 85
IS - 3
SP - 415-449
SN - 1776-3371
KW - parabolic variational inequalities
KW - Lagrange multipliers
KW - feasible and unfeasible regularization
KW - Black-Scholes
ER -
TY - JOUR
TI - Optimal design of redundant water distribution networks using a cluster of workstations
AU - Kumar, S. V.
AU - Doby, T. A.
AU - Baugh, J. W.
AU - Brill, E. D.
AU - Ranjithan, S. R.
T2 - Journal of Water Resources Planning and Management
AB - A genetic algorithm (GA)-based method for the least-cost design of looped pipe networks for various levels of redundancy is presented in this paper. Redundancy constraints are introduced in the optimization model by considering the number of pipes assumed to be out of service at any one time. Using this approach, trade-off relationships between cost and redundancy are developed. The GA-based approach is computationally intensive, and implementations on a custom fault-tolerant distributed computing framework, called Vitri, are used to satisfy the computational requirements. The design methodology is applied to two water distribution networks of different sizes, and a comparison of the performance of the distributed GAs for the design problems is also presented. We conclude that a GA-based approach to obtaining cost-effective, redundant solutions for the least-cost design of looped pipe networks can be effectively used on a heterogeneous network of nondedicated workstations.
DA - 2006///
PY - 2006///
DO - 10.1061/(ASCE)0733-9496(2006)132:5(374)
VL - 132
IS - 5
SP - 374-384
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33747304468&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Modeling baroreflex regulation of heart rate during orthostatic stress
AU - Olufsen, Mette S.
AU - Tran, Hien T.
AU - Ottesen, Johnny T.
AU - Lipsitz, Lewis A.
AU - Novak, Vera
T2 - AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY
AB - During orthostatic stress, arterial and cardiopulmonary baroreflexes play a key role in maintaining arterial pressure by regulating heart rate. This study presents a mathematical model that can predict the dynamics of heart rate regulation in response to postural change from sitting to standing. The model uses blood pressure measured in the finger as an input to model heart rate dynamics in response to changes in baroreceptor nerve firing rate, sympathetic and parasympathetic responses, vestibulo-sympathetic reflex, and concentrations of norepinephrine and acetylcholine. We formulate an inverse least squares problem for parameter estimation and successfully demonstrate that our mathematical model can accurately predict heart rate dynamics observed in data obtained from healthy young, healthy elderly, and hypertensive elderly subjects. One of our key findings indicates that, to successfully validate our model against clinical data, it is necessary to include the vestibulo-sympathetic reflex. Furthermore, our model reveals that the transfer between the nerve firing and blood pressure is nonlinear and follows a hysteresis curve. In healthy young people, the hysteresis loop is wide, whereas, in healthy and hypertensive elderly people, the hysteresis loop shifts to higher blood pressure values, and its area is diminished. Finally, for hypertensive elderly people, the hysteresis loop is generally not closed, indicating that, during postural change from sitting to standing, baroreflex modulation does not return to steady state during the first minute of standing.
DA - 2006/11//
PY - 2006/11//
DO - 10.1152/ajpregu.00205.2006
VL - 291
IS - 5
SP - R1355-R1368
SN - 1522-1490
KW - mathematical modeling
KW - heart rate control
KW - baroreflex function
KW - sympathetic and parasympathetic responses
KW - vestibulo-sympathetic reflex
ER -
TY - BOOK
TI - Incorporating commitment protocols into Tropos
AU - Mallya, A.U.
AU - Singh, Munindar P.
DA - 2006///
PY - 2006///
DO - 10.1007/11752660_6
VL - 3950 LNCS
PB - Berlin: Springer
SE - 69-80
SN - 3540340971
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33745861698&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Experimental validation of a homogenized energy model for magnetic after-effects
AU - Braun, TR
AU - Smith, RC
AU - Dapino, MJ
T2 - APPLIED PHYSICS LETTERS
AB - In this letter, we experimentally validate the ability of a recently developed ferromagnetic hysteresis model to characterize magnetic after-effects in ferromagnetic materials. The modeling framework, which combines energy analysis at the lattice level with stochastic homogenization techniques to accommodate material, stress, and field nonhomogeneities, quantifies after-effects through a balance of the Gibbs and relative thermal energies. Attributes of the framework are illustrated through fits to experimental steel data.
DA - 2006/3/20/
PY - 2006/3/20/
DO - 10.1063/1.2188595
VL - 88
IS - 12
SP -
SN - 1077-3118
ER -
TY - JOUR
TI - Constructing generalized mean functions using convex functions with regularity conditions
AU - Zhao, Yun-Bin
AU - Fang, Shu-Cherng
AU - Li, Duan
T2 - SIAM JOURNAL ON OPTIMIZATION
AB - The generalized mean function has been widely used in convex analysis and mathematical programming. This paper studies a further generalization of such a function. A necessary and sufficient condition is obtained for the convexity of a generalized function. Additional sufficient conditions that can be easily checked are derived for the purpose of identifying some classes of functions which guarantee the convexity of the generalized functions. We show that some new classes of convex functions with certain regularity (such as S*-regularity) can be used as building blocks to construct such generalized functions.
DA - 2006///
PY - 2006///
DO - 10.1137/040603838
VL - 17
IS - 1
SP - 37-51
SN - 1095-7189
KW - convexity
KW - mathematical programming
KW - generalized mean function
KW - self-concordant functions
KW - S*-regular functions
ER -
TY - JOUR
TI - A theoretical approach to characterising setups in batch fabric dyeing operations
AU - Cho, Eunkyoung G.
AU - Thoney, Kristin A.
AU - Krauss, Jeffrey D.
T2 - COLORATION TECHNOLOGY
AB - Traditionally, most of the research published on dyeing has been on achievements in optimising the mechanical and chemical technology associated with the physical dyeing process. However, relatively little research is available in the area of scheduling dyeing operations. This could be due to a lack of information available about dyeing setups. In this study, a theoretical approach to structuring machine-cleaning setups in batch fabric dyeing operations based on the CIELAB L*C*h colour space and the tolerance of the human visual system is presented. This will permit more research on the detailed scheduling of dyeing operations that could ultimately help dyeing facilities to better meet the needs of their customers in terms of improving on-time delivery.
DA - 2006///
PY - 2006///
DO - 10.1111/j.1478-4408.2006.00021.x
VL - 122
IS - 3
SP - 145-152
SN - 1478-4408
ER -
TY - JOUR
TI - A population-based latent variable approach for association mapping of quantitative trait loci
AU - Wang, T
AU - Weir, B
AU - Zeng, ZB
T2 - ANNALS OF HUMAN GENETICS
AB - A population-based latent variable approach is proposed for association mapping of quantitative trait loci (QTL), using multiple closely linked genetic markers within a small candidate region in the genome. By incorporating QTL as latent variables into a penetrance model, the QTL are flexible to characterize either alleles at putative trait loci or potential risk haplotypes/sub-haplotypes of the markers. Under a general likelihood framework, we develop an EM-based algorithm to estimate genetic effects of the QTL and haplotype frequencies of the QTL and markers jointly. Closed form solutions derived in the maximization step of the EM procedure for updating the joint haplotype frequencies of QTL and markers can effectively reduce the computational intensity. Various association measures between QTL and markers can then be derived from the haplotype frequencies of markers and used to infer QTL positions. The likelihood ratio statistic also provides a joint test for association between a quantitative trait and marker genotypes without requiring adjustment for the multiple testing. Extensive simulation studies are performed to evaluate the approach.
DA - 2006/7//
PY - 2006/7//
DO - 10.1111/j.1469-1809.2006.00264.x
VL - 70
SP - 506-523
SN - 0003-4800
KW - association mapping
KW - maximum likelihood
KW - haplotype
KW - latent variable
KW - EM algorithm
ER -
TY - JOUR
TI - Visual factors affecting touchdown point judgments during off-airport emergency landings
AU - Mayer, Celeste M.
AU - Mershon, Donald H.
AU - Lim, Raymond W.
AU - Chipley, M. Ryan
AU - McAllister, David F.
T2 - INTERNATIONAL JOURNAL OF AVIATION PSYCHOLOGY
AB - This article provides a comprehensive discussion of research designed to examine the possible existence of consistent visual misperceptions that may occur during off-airport emergency landings. The importance of 2 particular visual experiences was evaluated: (a) the view of the world seen from the unusually steep bank at a low altitude, and (b) the visual distraction of a windmilling propeller. The influences of experience and environmental structure were also considered. Studies of these factors were conducted using a visually realistic cockpit mounted within a VisionDome
DA - 2006///
PY - 2006///
DO - 10.1207/s15327108ijap1604_4
VL - 16
IS - 4
SP - 401-418
SN - 1050-8414
ER -
TY - JOUR
TI - Pattern avoidance in compositions and multiset permutations
AU - Savage, CD
AU - Wilf, HS
T2 - ADVANCES IN APPLIED MATHEMATICS
AB - We show that among the compositions of n into positive parts, the number g(n) that avoid a given pattern π of three letters is independent of π. We find the generating function of {g(n)}, and it shows that the sequence {g(n)} is not P-recursive. If S is a given multiset, we show that the number of permutations of S that avoid a pattern π of three letters is independent of π. Finally, we give a bijective proof of the fact that if M=1a1…kak is a given multiset then the number of permutations of M that avoid the pattern (123) is a symmetric function of the multiplicities a1,…,ak. The bijection uses the Greene–Kleitman symmetric chain decomposition of the Boolean lattice.
DA - 2006/2//
PY - 2006/2//
DO - 10.1016/j.aam.2005.06.003
VL - 36
IS - 2
SP - 194-201
SN - 1090-2074
ER -
TY - JOUR
TI - Parallel parameter study of the Wigner-Poisson equations for RTDs
AU - Lasater, M. S.
AU - Kelley, C. T.
AU - Salinger, A. G.
AU - Woolard, D. L.
AU - Zhao, P.
T2 - COMPUTERS & MATHEMATICS WITH APPLICATIONS
AB - We will discuss a parametric study of the solution of the Wigner-Poisson equations for resonant tunneling diodes. These structures exhibit self-sustaining oscillations in certain operating regimes. We will describe the engineering consequences of our study and how it is a significant advance from some previous work, which used much coarser grids. We use LOCA and other packages in the Trilinos framework from Sandia National Laboratory to enable efficient parallelization of the solution methods and to perform bifurcation analysis of this model. We report on the parallel efficiency and scalability of our implementation.
DA - 2006/6//
PY - 2006/6//
DO - 10.1016/j.camwa.2006.05.006
VL - 51
IS - 11
SP - 1677-1688
SN - 1873-7668
KW - Wigner-Poisson equation
KW - resonant tunneling diode
KW - continuation
KW - LOCA
KW - scalability
ER -
TY - JOUR
TI - Nonstationary analysis of circuit-switched communication networks
AU - Alnowibet, Khalid Abdulaziz
AU - Perros, Harry
T2 - PERFORMANCE EVALUATION
AB - Circuit-switched communication networks have been analyzed extensively in the stationary case, i.e. where the arrival and/or service rates are independent of time. In this paper, we study a circuit-switched network where the rates of external arrivals at the network are time-dependent functions. The circuit-switched network is modelled as a nonstationary queueing network with population constraints, which is analyzed approximately in order to obtain the blocking probability functions. Using this method we model two circuit-switched networks, namely, a traffic-groomed tandem optical network and a single-orbit LEO satellite network.
DA - 2006/10//
PY - 2006/10//
DO - 10.1016/j.peva.2005.10.001
VL - 63
IS - 9-10
SP - 892-909
SN - 1872-745X
KW - queueing networks
KW - nonstationary arrivals
KW - circuit-switched networks
KW - traffic grooming
KW - LEO satellite networks
ER -
TY - JOUR
TI - Multiple-interval mapping for ordinal traits
AU - Li, Jian
AU - Wang, Shengchu
AU - Zeng, Zhao-Bang
T2 - GENETICS
AB - Abstract Many statistical methods have been developed to map multiple quantitative trait loci (QTL) in experimental cross populations. Among these methods, multiple-interval mapping (MIM) can map QTL with epistasis simultaneously. However, the previous implementation of MIM is for continuously distributed traits. In this study we extend MIM to ordinal traits on the basis of a threshold model. The method inherits the properties and advantages of MIM and can fit a model of multiple QTL effects and epistasis on the underlying liability score. We study a number of statistical issues associated with the method, such as the efficiency and stability of maximization and model selection. We also use computer simulation to study the performance of the method and compare it to other alternative approaches. The method has been implemented in QTL Cartographer to facilitate its general usage for QTL mapping data analysis on binary and ordinal traits.
DA - 2006/7//
PY - 2006/7//
DO - 10.1534/genetics.105.054619
VL - 173
IS - 3
SP - 1649-1663
SN - 0016-6731
ER -
TY - JOUR
TI - Memory-efficient Kronecker algorithms with applications to the modelling of parallel systems
AU - Benoit, Anne
AU - Plateau, Brigitte
AU - Stewart, William J.
T2 - FUTURE GENERATION COMPUTER SYSTEMS-THE INTERNATIONAL JOURNAL OF ESCIENCE
AB - We present a new algorithm for computing the solution of large Markov chain models whose generators can be represented in the form of a generalized tensor algebra, such as networks of stochastic automata. The tensor structure inherently involves a product state space but, inside this product state space, the actual reachable state space can be much smaller. For such cases, we propose an improvement of the standard numerical algorithm, the so-called “shuffle algorithm”, which necessitates only vectors of the size of the actual state space. With this contribution, numerical algorithms based on tensor products can now handle larger models.
DA - 2006/8//
PY - 2006/8//
DO - 10.1016/j.future.2006.02.006
VL - 22
IS - 7
SP - 838-847
SN - 1872-7115
KW - large and sparse Markov chains
KW - stochastic automata networks
KW - generalized tensor algebra
KW - vector-descriptor multiplication
KW - shuffle algorithm
ER -
TY - JOUR
TI - Integrating XML data sources using approximate joins
AU - Guha, Sudipto
AU - Jagadish, H. V.
AU - Koudas, Nick
AU - Srivastava, Divesh
AU - Yu, Ting
T2 - ACM TRANSACTIONS ON DATABASE SYSTEMS
AB - XML is widely recognized as the data interchange standard of tomorrow because of its ability to represent data from a variety of sources. Hence, XML is likely to be the format through which data from multiple sources is integrated. In this article, we study the problem of integrating XML data sources through correlations realized as join operations. A challenging aspect of this operation is the XML document structure. Two documents might convey approximately or exactly the same information but may be quite different in structure. Consequently, an approximate match in structure, in addition to content, has to be folded into the join operation. We quantify an approximate match in structure and content for pairs of XML documents using well defined notions of distance. We show how notions of distance that have metric properties can be incorporated in a framework for joins between XML data sources and introduce the idea of reference sets to facilitate this operation. Intuitively, a reference set consists of data elements used to project the data space. We characterize what constitutes a good choice of a reference set, and we propose sampling-based algorithms to identify them. We then instantiate our join framework using the tree edit distance between a pair of trees. We next turn our attention to utilizing well known index structures to improve the performance of approximate XML join operations. We present a methodology enabling adaptation of index structures for this problem, and we instantiate it in terms of the R-tree. We demonstrate the practical utility of our solutions using large collections of real and synthetic XML data sets, varying parameters of interest, and highlighting the performance benefits of our approach.
DA - 2006/3//
PY - 2006/3//
DO - 10.1145/1132863.1132868
VL - 31
IS - 1
SP - 161-207
SN - 1557-4644
KW - algorithms
KW - experimentation
KW - performance
KW - theory
KW - data integration
KW - tree edit distance
KW - XML
KW - joins
KW - approximate joins
ER -
TY - JOUR
TI - Determination of interrogating frequencies to maximize electromagnetic backscatter from objects with material coatings
AU - Banks, H. T.
AU - Ito, K.
AU - Toivanen, J.
T2 - Communications in Computational Physics
DA - 2006///
PY - 2006///
VL - 1
IS - 2
SP - 362-382
ER -
TY - JOUR
TI - A homogenized energy framework for ferromagnetic hysteresis
AU - Smith, Ralph C.
AU - Dapino, Marcelo J.
AU - Braun, Thomas R.
AU - Mortensen, Anthony P.
T2 - IEEE TRANSACTIONS ON MAGNETICS
AB - This paper focuses on the development of a homogenized energy model which quantifies certain facets of the direct magnetomechanical effect. In the first step of the development, Gibbs energy analysis at the lattice level is combined with Boltzmann principles to quantify the local average magnetization as a function of input fields and stresses. A macroscopic magnetization model, which incorporates the effects of polycrystallinity, material nonhomogeneities, stress-dependent interaction fields, and stress-dependent coercive behavior, is constructed through stochastic homogenization techniques based on the tenet that local coercive and interaction fields are manifestations of underlying distributions rather than constants. The resulting framework incorporates previous ferromagnetic hysteresis theory as a special case in the absence of applied stresses. Attributes of the framework are illustrated through comparison with previously published steel and iron data
DA - 2006/7//
PY - 2006/7//
DO - 10.1109/TMAG.2006.875717
VL - 42
IS - 7
SP - 1747-1769
SN - 1941-0069
KW - actuators
KW - Boltzmann equation
KW - magnetic hysteresis
KW - modeling
KW - nonlinear magnetics
ER -
TY - JOUR
TI - Fast solvers for 3D Poisson equations involving interfaces in a finite or the infinite domain
AU - Lai, MC
AU - Li, ZL
AU - Lin, XB
T2 - JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS
AB - In this paper, numerical methods are proposed for Poisson equations defined in a finite or infinite domain in three dimensions. In the domain, there can exists an interface across which the source term, the flux, and therefore the solution may be discontinuous. The existence and uniqueness of the solution are also discussed. To deal with the discontinuity in the source term and in the flux, the original problem is transformed to a new one with a smooth solution. Such a transformation can be carried out easily through an extension of the jumps along the normal direction if the interface is expressed as the zero level set of a three-dimensional function. An auxiliary sphere is used to separate the infinite region into an interior and exterior domain. The Kelvin's inversion is used to map the exterior domain into an interior domain. The two Poisson equations defined in the interior and the exterior written in spherical coordinates are solved simultaneously. By choosing the mesh size carefully and exploiting the fast Fourier transform, the resulting finite difference equations can be solved efficiently. The approach in dealing with the interface has also been used with the artificial boundary condition technique which truncates the infinite domain. Numerical results demonstrate second order accuracy of our algorithms.
DA - 2006/6/15/
PY - 2006/6/15/
DO - 10.1016/j.cam.2005.04.025
VL - 191
IS - 1
SP - 106-125
SN - 1879-1778
KW - arbitrary interface
KW - fast 3D Poisson solver
KW - immersed interface method
KW - infinite domain
KW - extension of jumps
KW - spherical coordinates
KW - level set function
KW - artificial boundary condition
ER -
TY - JOUR
TI - Auxiliary signal design for active failure detection in uncertain linear systems with a priori information
AU - Nikoukhah, R
AU - Campbell, SL
T2 - AUTOMATICA
AB - A method for auxiliary signal design for active failure detection based on a multi-model formulation of normal and failed systems is developed which allows for a priori information about initial conditions and the possibility of having a known input in addition to the test signal. These results permit the consideration of additional types of failures, such as biases, that a previous approach could not handle. Both theoretical results and computational algorithms are developed.
DA - 2006/2//
PY - 2006/2//
DO - 10.1016/j.automatica.2005.09.011
VL - 42
IS - 2
SP - 219-228
SN - 1873-2836
KW - failure detection
KW - active detection
KW - test signal construction
KW - model-based fault detection
ER -
TY - JOUR
TI - Validation of two major quantitative trait loci for fusarium head blight resistance in Chinese wheat line W14
AU - Chen, J
AU - Griffey, CA
AU - Maroof, MAS
AU - Stromberg, EL
AU - Biyashev, RM
AU - Zhao, W
AU - Chappell, MR
AU - Pridgen, TH
AU - Dong, Y
AU - Zeng, Z
T2 - PLANT BREEDING
AB - Identity of quantitative trait loci (QTL) governing resistance to fusarium head blight (FHB) initial infection (type I), spread (type II), kernel infection, and deoxynivalenol (DON) accumulation was characterized in Chinese wheat line W14. Ninety-six double-haploid lines derived from a cross of W14 × ’Pion2684’ were evaluated for FHB resistance in two greenhouse and one field experiment. Two known major QTL were validated on chromosomes 3BS and 5AS in W14 using the composite interval mapping method. The 3BS QTL had a larger effect on resistance than the 5AS QTL in the greenhouse experiments, whereas, the 5AS QTL had a larger effect in the field experiment. These two QTL together explained 33%, 35%, and 31% of the total phenotypic variation for disease spread, kernel infection, and DON concentration in the greenhouse experiments, respectively. In the field experiment, the two QTL explained 34% and 26% of the total phenotypic variation for FHB incidence and severity, respectively. W14 has both QTL, which confer reduced initial infection, disease spread, kernel infection, and DON accumulation. Therefore, marker-assisted selection (MAS) for both QTL should be implemented in incorporating W14 resistance into adapted backgrounds. Flanking markers Xbarc133 and Xgwm493 on 3BS and Xbarc117 and Xbarc56 on 5AS are suggested for MAS.
DA - 2006/2//
PY - 2006/2//
DO - 10.1111/j.1439-0523.2006.01182.x
VL - 125
IS - 1
SP - 99-101
SN - 1439-0523
KW - Triticum aestivum
KW - Fusarium head blight
KW - microsatellite
KW - QTL mapping
ER -
TY - JOUR
TI - Sequencing precedence-related jobs on two machines to minimize the weighted completion time
AU - Ramachandra, G
AU - Elmaghraby, SE
T2 - INTERNATIONAL JOURNAL OF PRODUCTION ECONOMICS
AB - We address the problem P2|prec|∑wjCj. The problem is known to be NP-hard. We offer a binary integer program (BIP) and a dynamic program (DP); the latter is based on the concept of “initial subsets” of jobs and the optic of “weighted earliness–tardiness”. Although the DP approach expands the size of problems that can be solved to optimality to almost twice that obtained by the BIP, it reaches its computational limit around 25 jobs with mean job processing time of 10. We then introduce a genetic algorithm (GA) procedure that is capable of solving any problem size, and further extends the domain of applicability to more than two machines in parallel (problem Pm|prec|∑wjCj). The BIP is used also to establish a good lower bound against which the performance of the GA procedure is measured for larger size problems. Experimental investigation of the GA procedure demonstrates that it is capable of achieving the optimum in very few iterations (less than 20), thanks to the manner in which the initial population is generated, and that early abortion still yields excellent approximation to the optimum as judged by its proximity to the lower bound.
DA - 2006/3//
PY - 2006/3//
DO - 10.1016/j.ijpe.2004.10.014
VL - 100
IS - 1
SP - 44-58
SN - 1873-7579
KW - scheduling
KW - parallel machines
KW - dynamic programming
KW - genetic algorithm
ER -
TY - JOUR
TI - Real-time identification of the draft system using neural network
AU - Chun, SY
AU - Bae, HJ
AU - Kim, SM
AU - Suh, MW
AU - Grady, P
AU - Lyoo, WS
AU - Yoon, WS
AU - Han, SS
T2 - FIBERS AND POLYMERS
DA - 2006/3//
PY - 2006/3//
DO - 10.1007/BF02933604
VL - 7
IS - 1
SP - 62-65
SN - 1875-0052
KW - draft system
KW - sliver
KW - control
KW - neural network
KW - modeling
ER -
TY - JOUR
TI - Classification of Escherichia coli K-12 ribosome binding sites
AU - May, EE
AU - Vouk, MA
AU - Bitzer, DL
T2 - IEEE ENGINEERING IN MEDICINE AND BIOLOGY MAGAZINE
AB - Drawing on parallels between genetic information processing in living organisms and the processing of communications data, we develop an error-control coding-based translation initiation classification system that uses an eleven base classification window. An overview of channel codes and a summary of the translation initiation process are presented. Parallels between the two are drawn and a brief review of a channel code model for translation initiation is shown. A block-code Bayesian classifier is presented and the results of applying the system to the translation start site location problem for Escherichia coli K-12 is discussed.
DA - 2006///
PY - 2006///
DO - 10.1109/memb.2006.1578668
VL - 25
IS - 1
SP - 90-97
SN - 0739-5175
ER -
TY - JOUR
TI - An automated multiresolution procedure for modeling complex arrival processes
AU - Kuhl, ME
AU - Sumant, SG
AU - Wilson, , JR
T2 - INFORMS JOURNAL ON COMPUTING
AB - To automate the multiresolution procedure of Kuhl et al. for modeling and simulating arrival processes that may exhibit a long-term trend, nested periodic phenomena (such as daily and weekly cycles), or both types of effects, we formulate a statistical-estimation method that involves the following steps at each resolution level corresponding to a basic cycle: (a) transforming the cumulative relative frequency of arrivals within the cycle (for example, the percentage of all arrivals as a function of the time of day within the daily cycle) to obtain a statistical model with approximately normal, constant-variance responses; (b) fitting a specially formulated polynomial to the transformed responses; (c) performing a likelihood ratio test to determine the degree of the fitted polynomial; and (d) fitting to the original (untransformed) responses a polynomial of the same form as in (b) with the degree determined in (c). A comprehensive experimental performance evaluation involving 100 independent replications of eight selected test processes demonstrates the accuracy and flexibility of the automated multiresolution procedure.
DA - 2006///
PY - 2006///
DO - 10.1287/ijoc.1040.0113
VL - 18
IS - 1
SP - 3-18
SN - 1526-5528
KW - simulation
KW - probability
KW - stochastic model applications
KW - statistics
KW - estimation
KW - statistical analysis
KW - nonhomogeneous Poisson processes
KW - time-dependent arrivals
ER -
TY - JOUR
TI - A level-set method for interfacial flows with surfactant
AU - Xu, JJ
AU - Li, ZL
AU - Lowengrub, J
AU - Zhao, HK
T2 - JOURNAL OF COMPUTATIONAL PHYSICS
AB - A level-set method for the simulation of fluid interfaces with insoluble surfactant is presented in two-dimensions. The method can be straightforwardly extended to three-dimensions and to soluble surfactants. The method couples a semi-implicit discretization for solving the surfactant transport equation recently developed by Xu and Zhao [J. Xu, H. Zhao. An Eulerian formulation for solving partial differential equations along a moving interface, J. Sci. Comput. 19 (2003) 573–594] with the immersed interface method originally developed by LeVeque and Li and [R. LeVeque, Z. Li. The immersed interface method for elliptic equations with discontinuous coefficients and singular sources, SIAM J. Numer. Anal. 31 (1994) 1019–1044] for solving the fluid flow equations and the Laplace–Young boundary conditions across the interfaces. Novel techniques are developed to accurately conserve component mass and surfactant mass during the evolution. Convergence of the method is demonstrated numerically. The method is applied to study the effects of surfactant on single drops, drop–drop interactions and interactions among multiple drops in Stokes flow under a steady applied shear. Due to Marangoni forces and to non-uniform Capillary forces, the presence of surfactant results in larger drop deformations and more complex drop–drop interactions compared to the analogous cases for clean drops. The effects of surfactant are found to be most significant in flows with multiple drops. To our knowledge, this is the first time that the level-set method has been used to simulate fluid interfaces with surfactant.
DA - 2006/3/1/
PY - 2006/3/1/
DO - 10.1016/j.jcp.2005.07.016
VL - 212
IS - 2
SP - 590-616
SN - 1090-2716
KW - incompressible stokes flow
KW - interfaces
KW - insoluble surfactant
KW - Marangoni force
KW - capillary force
KW - level set method
KW - immersed interface method
ER -
TY - JOUR
TI - Variational approach to shape derivatives for a class of Bernoulli problems
AU - Ito, K
AU - Kunisch, K
AU - Peichl, GH
T2 - JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS
AB - The shape derivative of a functional related to a Bernoulli problem is derived without using the shape derivative of the state. The gradient information is combined with level set ideas in a steepest descent algorithm. Numerical examples show the feasibility of the approach.
DA - 2006/2/1/
PY - 2006/2/1/
DO - 10.1016/j.jmaa.2005.03.100
VL - 314
IS - 1
SP - 126-149
SN - 1096-0813
KW - shape derivative
KW - Bernoulli problem
KW - level set
ER -
TY - JOUR
TI - Traffic grooming in WDM ring networks to minimize the maximum electronic port cost.
AU - Chen, B.
AU - Rouskas, G.
AU - Dutta, R.
T2 - Optical Switching and Networking
DA - 2006///
PY - 2006///
VL - 2
IS - 1
SP - 1-18
ER -
TY - JOUR
TI - Scheduling of a two-machine flowshop with availability constraints on the first machine
AU - Allaoui, H
AU - Artiba, A
AU - Elmaghraby, SE
AU - Riane, F
T2 - INTERNATIONAL JOURNAL OF PRODUCTION ECONOMICS
AB - We treat the problem of scheduling n immediately available jobs in a flowshop composed of two machines in series with the objective of minimizing the makespan, when it is known that there shall be an interruption in machine availability on the first machine. We also consider two types of processing regimes: “stop resume” and “stop restart”. We present efficient dynamic program models for both regimes. But we focus on the performance of the Johnson rule as a heuristic. We establish the conditions under which it yields the optimum, and demonstrate that in other cases its performance is bounded by 2.
DA - 2006///
PY - 2006///
DO - 10.1016/j.ijpe.2004.12.003
VL - 99
IS - 1-2
SP - 16-27
SN - 1873-7579
KW - scheduling
KW - availability constraints
KW - flowshop
ER -
TY - JOUR
TI - Physiologically-based pharmacokinetic modeling of benzene in humans: A Bayesian approach
AU - Yokley, Karen
AU - Tran, Hien T.
AU - Pekari, Kaija
AU - Rappaport, Stephen
AU - Riihimaki, Vesa
AU - Rothman, Nat
AU - Waidyanatha, Suramya
AU - Schlosser, Paul M.
T2 - RISK ANALYSIS
AB - Benzene is myelotoxic and leukemogenic in humans exposed at high doses (>1 ppm, more definitely above 10 ppm) for extended periods. However, leukemia risks at lower exposures are uncertain. Benzene occurs widely in the work environment and also indoor air, but mostly below 1 ppm, so assessing the leukemia risks at these low concentrations is important. Here, we describe a human physiologically-based pharmacokinetic (PBPK) model that quantifies tissue doses of benzene and its key metabolites, benzene oxide, phenol, and hydroquinone after inhalation and oral exposures. The model was integrated into a statistical framework that acknowledges sources of variation due to inherent intra- and interindividual variation, measurement error, and other data collection issues. A primary contribution of this work is the estimation of population distributions of key PBPK model parameters. We hypothesized that observed interindividual variability in the dosimetry of benzene and its metabolites resulted primarily from known or estimated variability in key metabolic parameters and that a statistical PBPK model that explicitly included variability in only those metabolic parameters would sufficiently describe the observed variability. We then identified parameter distributions for the PBPK model to characterize observed variability through the use of Markov chain Monte Carlo analysis applied to two data sets. The identified parameter distributions described most of the observed variability, but variability in physiological parameters such as organ weights may also be helpful to faithfully predict the observed human-population variability in benzene dosimetry.
DA - 2006/8//
PY - 2006/8//
DO - 10.1111/j.1539-6924.2006.00789.x
VL - 26
IS - 4
SP - 925-943
SN - 0272-4332
KW - Bayesian
KW - benzene
KW - dosimetry
KW - human
KW - metabolism
KW - PBPK
KW - variability
ER -
TY - JOUR
TI - Monte Carlo simulation of a solvated ionic polymer with cluster morphology
AU - Matthews, JL
AU - Lada, EK
AU - Weiland, LM
AU - Smith, RC
AU - Leo, DJ
T2 - SMART MATERIALS & STRUCTURES
AB - A multiscale modeling approach for the prediction of material stiffness of the ionic polymer Nafion is presented. Traditional rotational isomeric state theory is applied in combination with a Monte Carlo methodology to develop a simulation model of the conformation of Nafion polymer chains on a nanoscopic level from which a large number of end-to-end chain lengths are generated. The probability density function of end-to-end distances is then estimated and used as an input parameter to enhance existing energetics-based macroscale models of ionic polymer behavior. Several methods for estimating the probability density function are compared, including estimation using Johnson distributions, Bézier distributions, and cubic splines.
DA - 2006/2//
PY - 2006/2//
DO - 10.1088/0964-1726/15/1/048
VL - 15
IS - 1
SP - 187-199
SN - 0964-1726
ER -
TY - JOUR
TI - A unified framework for modeling hysteresis in ferroic materials
AU - Smith, RC
AU - Seelecke, S
AU - Dapino, M
AU - Ounaies, Z
T2 - JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
AB - This paper addresses the development of a unified framework for quantifying hysteresis and constitutive nonlinearities inherent to ferroelectric, ferromagnetic and ferroelastic materials. Because the mechanisms which produce hysteresis vary substantially at the microscopic level, it is more natural to initiate model development at the mesoscopic, or lattice, level where the materials share common energy properties along with analogous domain structures. In the first step of the model development, Helmholtz and Gibbs energy relations are combined with Boltzmann theory to construct mesoscopic models which quantify the local average polarization, magnetization and strains in ferroelectric, ferromagnetic and ferroelastic materials. In the second step of the development, stochastic homogenization techniques are invoked to construct unified macroscopic models for nonhomogeneous, polycrystalline compounds exhibiting nonuniform effective fields. The combination of energy analysis and homogenization techniques produces low-order models in which a number of parameters can be correlated with physical attributes of measured data. Furthermore, the development of a unified modeling framework applicable to a broad range of ferroic compounds facilitates material characterization, transducer development, and model-based control design. Attributes of the models are illustrated through comparison with piezoceramic, magnetostrictive and shape memory alloy data and prediction of material behavior.
DA - 2006/1//
PY - 2006/1//
DO - 10.1016/j.jmps.2005.08.006
VL - 54
IS - 1
SP - 46-85
SN - 1873-4782
KW - ferroic materials
KW - unified models
KW - hysteresis
KW - constitutive nonlinearities
ER -
TY - JOUR
TI - A simulation study of IP-based vertical handoff in wireless convergent networks
AU - Song, Lung Kee
AU - Wang, Wenye
T2 - WIRELESS COMMUNICATIONS & MOBILE COMPUTING
AB - Summary The advances in wireless networks and IP technologies has brought ubiquitous access to all-IP information into reality. For wireless IP services, IP-based handoff is a critical issue to the performance of application-level services. Although mobile IP (MIP) and its extensions, as network layer solutions, have been proposed as de facto standard, transmission throughput degradation due to packet loss, registration delay, and transport layer blocking are unavoidable because of MIP handoff mechanisms. In this paper, we evaluate the performance of a transport layer handoff approach, mobile stream control transmission protocol (mSCTP), and compare it with that of a network layer solution, MIP. mSCTP is based on stream control transmission protocol (SCTP), which is the third general purpose transport layer protocol from IETF. We investigate the use of mSCTP for seamless vertical handoff without any change in IP protocol stack by its multi-homing feature and dynamic address reconfiguration (DAR) extension. We evaluate the performance of mSCTP and MIP by introducing handoff delay, end-to-end transmission throughput, and packet loss, and verify our observations by a simulation study of the two protocols in UMTS/802.11b integrated networks using NS-2 network simulator. Copyright © 2006 John Wiley & Sons, Ltd.
DA - 2006/8//
PY - 2006/8//
DO - 10.1002/wcm.415
VL - 6
IS - 5
SP - 629-650
SN - 1530-8677
KW - handoff
KW - heterogeneous wireless networks
KW - mobile IP
KW - UMTS/WLANs
ER -
TY - JOUR
TI - A performance study of an optical burst switched network with dynamic simultaneous link possession
AU - Battestilli, T
AU - Perros, H
T2 - COMPUTER NETWORKS
AB - In optical burst switched (OBS) networks a burst may occupy a wavelength on one or more links as it travels through the network. In the literature, OBS networks have been analyzed assuming that each burst occupies only a wavelength on a single link. In this paper, we study analytically the performance of an OBS network with a mixture of different size bursts. The short bursts occupy a wavelength on a single link while the long bursts occupy simultaneously wavelengths on multiple consecutive links. We develop a queueing network, which models simultaneous link possession, and we calculate analytically the end-to-end burst loss probabilities over a path in the OBS network. Our results indicate that having a mix of various size bursts can greatly effect the burst loss probabilities in the network.
DA - 2006/2/8/
PY - 2006/2/8/
DO - 10.1016/j.comnet.2005.05.021
VL - 50
IS - 2
SP - 219-236
SN - 1872-7069
KW - optical burst switching (OBS)
KW - optical networks
KW - queueing network
KW - simultaneous resource possession
KW - burst loss probability
KW - decomposition algorithm
KW - traffic model
ER -
TY - JOUR
TI - Interface conditions for Stokes equations with a discontinuous viscosity and surface sources
AU - Ito, K
AU - Li, ZL
T2 - APPLIED MATHEMATICS LETTERS
AB - The interface conditions, or jump conditions, for the pressure and the velocity of the solution to the incompressible Stokes equations with a discontinuous viscosity and a singular source along an interface are derived in this work. While parts of the results agree with those in the literature, some of the results are new. These theoretical results are useful for developing accurate numerical methods for the interface problem.
DA - 2006/3//
PY - 2006/3//
DO - 10.1016/j.aml.2005.02.041
VL - 19
IS - 3
SP - 229-234
SN - 0893-9659
KW - incompressible Stokes equations
KW - interface
KW - discontinuous viscosity
KW - interface conditions
KW - singular sources
ER -
TY - CHAP
TI - Finding equivalent rewritings in the presence of arithmetic comparisons
AU - Afrati, F.
AU - Chirkova, R.
AU - Gergatsoulis, M.
AU - Pavlaki, V.
T2 - Advances in database technology :
EDBT 2006 : 10th International Conference on Extending Database Technology, Munich, Germany, March 26-31, 2006: Proceedings (Lecture notes in computer science; 3896)
AB - AbstractThe problem of rewriting queries using views has received significant attention because of its applications in a wide variety of data-management problems. For select-project-join SQL (a.k.a. conjunctive) queries and views, there are efficient algorithms in the literature, which find equivalent and maximally contained rewritings. In the presence of arithmetic comparisons (ACs) the problem becomes more complex. We do not know how to find maximally contained rewritings in the general case. There are algorithms which find maximally contained rewritings only for special cases such as when ACs are restricted to be semi-interval. However, we know that the problem of finding an equivalent rewriting (if there exists one) in the presence of ACs is decidable, yet still doubly exponential. This complexity calls for an efficient algorithm which will perform better on average than the complete enumeration algorithm. In this work we present such an algorithm which is sound and complete. Its efficiency lies in that it considers fewer candidate rewritings because it includes a preliminary test to decide for each view whether it is potentially useful in some rewriting.
PY - 2006///
DO - 10.1007/11687238_55
VL - 3896
SP - 942-960
PB - Berlin: Springer
ER -
TY - JOUR
TI - Developing portfolios of water supply transfers
AU - Characklis, GW
AU - Kirsch, BR
AU - Ramsey, J
AU - Dillard, KEM
AU - Kelley, CT
T2 - WATER RESOURCES RESEARCH
AB - [1] Most cities rely on firm water supply capacity to meet demand, but increasing scarcity and supply costs are encouraging greater use of temporary transfers (e.g., spot leases, options). This raises questions regarding how best to coordinate the use of these transfers in meeting cost and reliability objectives. This paper combines a hydrologic–water market simulation with an optimization approach to identify portfolios of permanent rights, options, and leases that minimize the expected costs of meeting a city's annual demand with a specified reliability. Spot market prices are linked to hydrologic conditions and described by monthly lease price distributions which are used to price options via a risk-neutral approach. Monthly choices regarding when and how much water to acquire through temporary transfers are made on the basis of anticipatory decision rules related to the ratio of expected supply to expected demand. The simulation is linked with an algorithm that uses an implicit filtering search method designed for solution surfaces that exhibit high-frequency, low-amplitude noise. This simulation-optimization approach is applied to a region that currently supports an active water market, with results suggesting that temporary transfers can reduce expected water supply costs substantially, while still maintaining high reliability. Also evaluated are trade-offs between expected costs and cost variability that occur with variation in a portfolio's distribution of rights, options, and leases.
DA - 2006/5/3/
PY - 2006/5/3/
DO - 10.1029/2005wr004424
VL - 42
IS - 5
SP -
SN - 1944-7973
ER -
TY - JOUR
TI - Dynamic bandwidth allocation by using efficient threshold reporting for quality of service in Ethernet passive optical networks
AU - Yang, Y. M.
AU - Nho, J. M.
AU - Perros, H.
AU - Mahalik, N. P.
AU - Kim, K.
AU - Ahn, B. H.
T2 - Optical Engineering (Redondo Beach, Calif.)
DA - 2006///
PY - 2006///
VL - 45
IS - 3
ER -
TY - JOUR
TI - Energy-efficient bandwidth allocation in wireless networks: Algorithms, analysis, and simulations
AU - Wang, Wenye
AU - Wang, Xinbing
AU - Nilsson, Arne. A.
T2 - IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
DA - 2006/5//
PY - 2006/5//
DO - 10.1109/TWC.2006.05018
VL - 5
IS - 5
SP - 1103-1114
SN - 1558-2248
KW - wireless networks
KW - energy consumption
KW - and connection admission control
ER -
TY - JOUR
TI - Variation in volume production through clonal deployment: Results from a simulation model to minimize risk for both a currently known and unknown future pest
AU - Yanchuk, A. D.
AU - Bishir, J.
AU - Russell, J. H.
AU - Polsson, K. R.
T2 - SILVAE GENETICA
AB - Abstract A simulation model was developed to examine optimum patterns of deploying selected clones in the hypothetical situations of both a currently known pest and an unknown future pest. We modelled the interactions between Sitka spruce (Picea sitchensis (Bong.) Carr.), an economically important forest tree in British Columbia and the northwestern U.S., and the spruce terminal weevil (Pissodes strobi (Peck)), a major pest in western spruces. The model is combined with the Province of British Columbia’s Tree and Stand Simulator (TASS) model to drive individual tree growth and stand establishment and development. Two clonal-sampling strategies are examined: a randomly drawn set of genotypes or clones, to depict the potential consequences of a new (e.g., exotic) or a previously unimportant natural pest attacking a ‘random’ set of genotypes, and a ‘fixed’ set of clones, emulating a ‘commercial’ or known set of clones for growth and resistance mechanisms. Simulations use a range of numbers of genotypes or clones (2, 6, 18 and 30), and three deployment patterns (a random mixture of ramets, single- clone blocks, and a mosaic of smaller clonal blocks), in one and five hectare (Ha) stands. Total merchantable timber volume on a per Ha basis at harvest age 80 is used to compare the various combinations and schemes. With both random and fixed chosen sets of clones, the random planting pattern (i.e., random mixture of ramets from the clonal set) produced the most volume. Eighteen randomly chosen clones generally produced more volume, than 2, 6 and 30 clones, but differences among 6, 18 and 30 clones were small in most cases, irrespective of planting pattern. For fixed clones, the use of more resistant clones with higher growth potential produced more volume; however, pure clonal blocks of the best clone were not better than a mixture of that clone and an inferior one. Reducing the effects of insect activity and attack on trees, by lowering the average annual temperature in the model, or turning off all insect ‘activity’, increased merchantable volume but did not change the optimum number of clones (~18) or deployment pattern (random mixture). Forestry agencies can weigh these findings against economic advantages of block plantings of similar genotypes, in the choice of an appropriate number of clones and a deployment strategy.
DA - 2006///
PY - 2006///
DO - 10.1515/sg-2006-0005
VL - 55
IS - 1
SP - 25-37
SN - 2509-8934
KW - clonal forestry
KW - genetic diversity
KW - risk
KW - merchantable volume loss
KW - insect resistance
ER -
TY - JOUR
TI - Theoretical analysis of the SABUL congestion control algorithm
AU - Oothongsap, P
AU - Viniotis, Y
AU - Vouk, M
T2 - TELECOMMUNICATION SYSTEMS
DA - 2006/3//
PY - 2006/3//
DO - 10.1007/s11235-006-6516-8
VL - 31
IS - 2-3
SP - 115-139
SN - 1572-9451
ER -
TY - JOUR
TI - Profit-oriented resource allocation using online scheduling in flexible heterogeneous networks
AU - Xu, P
AU - Michailidis, G
AU - Devetsikiotis, M
T2 - TELECOMMUNICATION SYSTEMS
AB - In this paper, we discuss a generalized measurement-based adaptive scheduling framework for dynamic resource allocation in flexible heterogeneous networks, in order to ensure efficient service level performance under inherently variable traffic conditions. We formulate our generalized optimization model based on the notion of a “profit center” with an arbitrary number of service classes, nonlinear revenue and cost functions and general performance constraints. Subsequently, and under the assumption of a linear pricing model and average queue delay requirements, we develop a fast, low complexity algorithm for online dynamic resource allocation, and examine its properties. Finally, the proposed scheme is validated through an extensive simulation study.
DA - 2006/3//
PY - 2006/3//
DO - 10.1007/s11235-006-6525-7
VL - 31
IS - 2-3
SP - 289-303
SN - 1572-9451
KW - resource allocation
KW - on line scheduling
KW - profit center
ER -
TY - JOUR
TI - Performance analysis of limited-range wavelength conversion in an OBS switch
AU - Puttasubbappa, VS
AU - Perros, HG
T2 - TELECOMMUNICATION SYSTEMS
DA - 2006/3//
PY - 2006/3//
DO - 10.1007/s11235-006-6522-x
VL - 31
IS - 2-3
SP - 227-246
SN - 1572-9451
KW - optical burst switching
KW - limited-range wavelength conversion
KW - performance evaluation
KW - simultaneous resource allocation
ER -
TY - JOUR
TI - Models and partition of variance for quantitative trait loci with epistasis and linkage disequilibrium
AU - Wang, T.
AU - Zeng, Z. B.
T2 - BMC Genetics
DA - 2006///
PY - 2006///
VL - 7
ER -
TY - JOUR
TI - Unit roots: Periodogram ordinate
AU - Bhattacharyya, BB
AU - Richardson, GD
AU - Flores, PV
T2 - STATISTICS & PROBABILITY LETTERS
AB - The periodogram ordinate is used to define an asymptotic test for the testing problem H0:α=1 vs. HA:|α|<1 under appropriate assumptions on the model Yt=αYt-1+εt-θεt-1, where θ is near one. A drift term is also included in the model. An independent and identically distributed error structure as well as one exhibiting long memory are studied.
DA - 2006/3/15/
PY - 2006/3/15/
DO - 10.1016/j.spl.2005.09.011
VL - 76
IS - 6
SP - 641-651
SN - 1879-2103
KW - autoregressive moving average processes
KW - unit roots
KW - periodograrn ordinate
KW - limiting distributions
ER -
TY - JOUR
TI - Determining sequence and ready times in a remanufacturing system
AU - Stanfield, PM
AU - King, RE
AU - Hodgson, TJ
T2 - IIE TRANSACTIONS
AB - A fundamental scheduling problem is to determine a production start (ready) time for jobs based on customer-specified due dates. Typically, the objective is to delay the ready time in an attempt to minimize work-in-process inventory and maximize production system utilization. In many practical situations, notably remanufacturing operations, highly variable operation times and intricate process plans complicate this problem. In such a case, a specific ready time implies a confidence of on-time completion. Prior analytical results imply the optimal solution is a function of: (i) customer due dates; (ii) desired confidence levels; and (iii) stochastic makespan minimization. This paper proposes the use of a network flow model to represent a remanufacturing flowshop and then presents a structured heuristic approach that is able to develop sequences and ready times for remanufacturing systems by balancing the three factors. A broad experimental design is used to demonstrate that the proposed scheduling method outperforms previous list rules in terms of the calculated mean and robustness values.
DA - 2006/7//
PY - 2006/7//
DO - 10.1080/07408170500371830
VL - 38
IS - 7
SP - 597-607
SN - 0740-817X
ER -
TY - JOUR
TI - Communicating applied mathematics: Four examples
AU - Finkel, Daniel E.
AU - Kuster, Christopher
AU - Lasater, Matthew
AU - Levy, Rachel
AU - Reese, Jill P.
AU - Ipsen, Ilse C. F.
T2 - SIAM REVIEW
AB - Communicating Applied Mathematics is a writing- and speaking-intensive graduate course at North Carolina State University. The purpose of this article is to provide a brief description of the course objectives and the assignments. Parts A--D of of this article represent the class projects and illustrate the outcome of the course: We introduce a water-supply problem considered by the optimization and hydrology communities for benchmarking purposes. The objective is to drill five wells so that the cost of pumping water out of the ground is minimized. Using the implicit filtering optimization algorithm to locate the wells, we save approximately $2,500 over the cost of a given initial well configuration. The volume of powder poured into a bin with obstructions is found by calculating the height of the surface at every point. This is done using the fast marching algorithm. We look at two different bin geometries and determine the volumes as a function of the powder height under the spout. The surface of the powder satisfies a two-dimensional eikonal equation. This equation is solved using the fast marching method. Resonant tunneling diodes (RTDs) are ultrasmall semiconductor devices that have potential as very high-frequency oscillators. To describe the electron transport within these devices, physicists use the Wigner--Poisson equations which incorporate quantum mechanics to describe the distribution of electrons within the RTD. Continuation methods are employed to determine the steady-state electron distributions as a function of the voltage difference across the device. These simulations predict the operating state of the RTD under different applied voltages and will be a tool to help physicists understand how changing the voltage applied to the device leads to the development of current oscillations. When a thin film flows down an inclined plane, a bulge of fluid, known as a capillary ridge, forms on the leading edge and is subject to a fingering instability in which the fluid is channeled into rivulets. This process is familiar to us in everyday experiments such as painting a wall or pouring syrup over a stack of pancakes. It is also observed that changes in surface tension due to a temperature gradient can draw fluid up an inclined plane. Amazingly, in this situation the capillary ridge broadens and no fingering instability is observed. Numerical and analytical studies of a mathematical model of this process led to the discovery that these observations are associated with a nonclassical shock wave previously unknown to exist in thin liquid films.
DA - 2006/6//
PY - 2006/6//
DO - 10.1137/S0036144504443523
VL - 48
IS - 2
SP - 359-389
SN - 1095-7200
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33744925177&partnerID=MN8TOARS
KW - education
KW - mathematical writing
KW - presentations
KW - audience
KW - peer critique
ER -
TY - JOUR
TI - Optical networks
AU - Perros, H
T2 - COMPUTER NETWORKS
DA - 2006/2/8/
PY - 2006/2/8/
DO - 10.1016/j.comnet.2005.05.020
VL - 50
IS - 2
SP - 145-148
SN - 1872-7069
ER -
TY - JOUR
TI - Gain-scheduling control of LFT systems using parameter-dependent Lyapunov functions
AU - Wu, F
AU - Dong, K
T2 - AUTOMATICA
AB - In this paper, we propose a new control design approach for linear fractional transformation (LFT) systems using parameter-dependent Lyapunov functions. Instead of assuming parameter dependency in LFT fashion, we consider general parameter-dependent controllers to achieve better closed-loop performance. Using full-block multipliers, new LPV synthesis conditions have been derived in terms of finite number of linear matrix inequalities (LMIs). Both continuous- and discrete-time cases are discussed. A ship steering example has been used to demonstrate advantages and benefits of the proposed approach.
DA - 2006/1//
PY - 2006/1//
DO - 10.1016/j.automatica.2005.08.020
VL - 42
IS - 1
SP - 39-50
SN - 1873-2836
KW - linear fractional transformation system
KW - parameter-dependent Lyapunov function
KW - full-block multiplier
KW - L-2 gain
KW - linear matrix inequality
ER -