TY - JOUR
TI - The SILO architecture for services integration, control, and optimization for the future Internet
AU - Dutta, Rudra
AU - Rouskas, George N.
AU - Baldine, Ilia
AU - Bragg, Arnold
AU - Stevenson, Dan
AU - IEEE
T2 - 2007 Ieee International Conference on Communications, Vols 1-14
AB - We propose a new internetworking architecture that represents a departure from current philosophy and practice, as a contribution to the ongoing debate regarding the future Internet. Building upon our experience with the design and prototyping of the just-in-time protocol suite, we outline a framework consisting of (1) building blocks of fine-grain functionality, (2) explicit support for combining elemental blocks to accomplish highly configurable complex communication tasks, and (3) control elements to facilitate (what is currently referred to as) cross-layer interactions. In this position paper, we take a holistic view of network design, allowing applications to work synergistically with the network architecture and physical layers to select the most appropriate functional blocks and tune their behavior so as to meet the application's needs within resource availability constraints. The proposed architecture is flexible and extensible so as to foster innovation and accommodate change, it supports a unified Internet, it allows for the integration of security and management features at any point in (what is now referred to as) the networking stack, and it is positioned to take advantage of hardware-based performance-enhancing techniques.
DA - 2007///
PY - 2007///
DO - 10.1109/ICC.2007.316
SP - 1899-1904
ER -
TY - JOUR
TI - TDM emulation in packet-switched networks
AU - Rouskas, George N.
AU - BaradwaJ, Nikhil
AU - IEEE
T2 - 2007 Ieee International Conference on Communications, Vols 1-14
AB - Many network operators offer some type of tiered service, in which users may select only from a small set of service levels (tiers). In this work, we study the problem of designing a tiered-service network that allocates bandwidth in multiples of a basic bandwidth unit. Such a packet-switched network can enjoy many of the benefits, in terms of control and management, of a TDM network, but without the associated data plane rigidities.
DA - 2007///
PY - 2007///
DO - 10.1109/ICC.2007.318
SP - 1911-1916
ER -
TY - JOUR
TI - On the suitability of composable services for the assurable future Internet
AU - Stevenson, Daniel
AU - Dutta, Rudra
AU - Rouskas, George
AU - Reeves, Douglas
AU - Baldine, Ilia
AU - IEEE
T2 - 2007 Ieee Military Communications Conference, Vols 1-8
DA - 2007///
PY - 2007///
SP - 3695-3701
ER -
TY - JOUR
TI - Hierarchical Grooming in Multigranular Networks
AU - Iyer, Mohan
AU - Rouskas, George N.
AU - Dutta, Rudra
AU - IEEE
T2 - 2007 First International Symposium on Advanced Networks and Telecommunication Systems
DA - 2007///
PY - 2007///
SP - 35-36
ER -
TY - JOUR
TI - Framework for tiered service in MPLS networks
AU - Rouskas, George N.
AU - Baradwaj, Nikhil
AU - IEEE
T2 - Infocom 2007, Vols 1-5
AB - Many network operators offer some type of tiered service, in which users may select only from a small set of service levels (tiers). Such a service has the potential to simplify a wide range of core network functions, allowing the providers to scale their operations efficiently. In this work, we provide a theoretical framework for reasoning about and tackling algorithmically the general problem of service tier selection. Drawing upon results from discrete location theory, we formulate the problem as a *p* -median problem under a new directional distance measure, and we develop efficient algorithms for a number of important variants. Our main finding is that, by appropriately selecting the set of service levels, network providers may realize the benefits of tiered service with only a small sacrifice in network resources.
DA - 2007///
PY - 2007///
DO - 10.1109/INFCOM.2007.185
SP - 1577-1585
ER -
TY - CHAP
TI - Clustering for hierarchical traffic grooming in large scale mesh WDM networks
AU - Chen, Bensong
AU - Dutta, Rudra
AU - Rouskas, George N.
AU - Tomkos, I
AU - Neri, F
AU - Pareta, JS
AU - Bruin, XM
AU - Lopez, SS
T2 - Optical Network Design and Modeling, Proceedings
PY - 2007///
VL - 4534
SP - 249-258
PB -
SE -
ER -
TY - CHAP
TI - A unified software architecture to enable cross-layer design in the future Internet
AU - Baldine, Ilia
AU - Vellala, Manoj
AU - Wang, Anjing
AU - Rouskas, George
AU - Dutta, Rudra
AU - Stevenson, Daniel
AU - IEEE
T2 - Proceedings - 16th International Conference on Computer Communications and Networks, Vols 1-3
PY - 2007///
SP - 26-32
PB -
SE -
ER -
TY - JOUR
TI - A practical and efficient implementation of WF(2)Q+
AU - Rouskas, George N.
AU - Dwekat, Zyad
AU - IEEE
T2 - 2007 Ieee International Conference on Communications, Vols 1-14
AB - The WF ^{2} Q+ scheduler combines all three properties that are important to a fair queueing algorithm: a tight delay bound, a small worst-case fair index value, and a relatively low worst-case complexity of *O* ( *log* *n* ) for a link with *n* flows. We present a new implementation of WF ^{2} Q+ in which both the number of packet sorting operations and the computation of the virtual time function are independent of the number *n* of flows. Our implementation exploits two widely observed characteristics of the Internet, namely that service providers offer some type of tiered service with a small number of service levels, and that a small number of packet sizes dominate. Our scheduler combines provably good performance with amenability to hardware implementation in high-speed routers.
DA - 2007///
PY - 2007///
DO - 10.1109/ICC.2007.36
SP - 172-176
ER -
TY - CONF
TI - Multiproduct Network Design Model with Lead Time and Safety Stock Considerations
AU - Sourirajan, K.
AU - Ozsen, L.
AU - Uzsoy, R.
T2 - INFORMS International Meeting
C2 - 2007/7//
CY - Rio Mar, Puerto Rico
DA - 2007/7//
PY - 2007/7//
ER -
TY - CONF
TI - Lead Time Based Heuristics for Integrated Production and Safety Stock Planning
AU - Orcun, S.
AU - Uzsoy, R.
AU - Kempf, K.G.
T2 - INFORMS International Meeting
C2 - 2007/7//
CY - Rio Mar, Puerto Rico
DA - 2007/7//
PY - 2007/7//
ER -
TY -
ER -
TY - CHAP
TI - Performance Analysis of Traffic-Groomed Optical Networks Employing Alternate Routing Techniques
AU - Washington, Nicki
AU - Perros, Harry
T2 - Managing Traffic Performance in Converged Networks. ITC 2007
A2 - Mason, L.
A2 - Drwiega, T.
A2 - Yan, J.
T3 - Lecture Notes in Computer Science
PY - 2007/9/1/
DO - 10.1007/978-3-540-72990-7_90
SP - 1048–1059
PB - Springer
SN - 9783540729891
SV - 4516
UR - http://dx.doi.org/10.1007/978-3-540-72990-7_90
ER -
TY - CHAP
TI - Analysis and Provisioning of a Circuit-Switched Link with Variable-Demand Customers
AU - Tian, Wenhong
AU - Perros, Harry
T2 - Managing Traffic Performance in Converged Networks. ITC 2007
A2 - Mason, L.
A2 - Drwirga, T.
A2 - Yan, J.
T3 - Lecture Notes in Computer Science
AB - We consider a single circuit-switched communication link, depicted by a Erlang multi-class loss queue, where a customer may vary its required bandwidth during its service. We obtain approximately the steady-state blocking probability of each class of customer. Comparisons with simulation results show that the approximation solution has a good accuracy. For the proposed model, we also provide an efficient capacity provisioning algorithm.
PY - 2007/9/1/
DO - 10.1007/978-3-540-72990-7_77
SP - 890–900
PB - Springer
SN - 9783540729891
SV - 4516
UR - http://dx.doi.org/10.1007/978-3-540-72990-7_77
ER -
TY - CHAP
TI - Measuring Bandwidth Signatures of Network Paths
AU - Neginhal, Mradula
AU - Harfoush, Khaled
AU - Perros, Harry
T2 - NETWORKING 2007. Ad Hoc and Sensor Networks, Wireless Networks, Next Generation Internet
A2 - Akyildiz, I.F.
A2 - Sivakumar, R.
A2 - Ekici, E.
A2 - Oliveira, J.C.
A2 - McNair, J.
T3 - Lecture Notes in Computer Science
AB - In this paper, we propose a practical and efficient technique, Forecaster, to estimate (1) the end-to-end available bandwidth, and (2) the speed of the most congested (tight) link along an Internet path. Forecaster is practical since it does not assume any a priori knowledge about the measured path, does not make any simplifying assumptions about the nature of cross-traffic, does not assume the ability to capture accurate packet dispersions or packet queueing delays, and does not try to preserve inter-packet spacing along path segments. It merely relies on a simple binary test to estimate whether each probe packet has queued in the network or not. Forecaster is efficient as it only requires two streams of probe packets that are sent end-to-end at rates that are much lower than the available bandwidth of the investigated path, thus avoiding path saturation. Theoretical analysis and experimental results validate the efficacy of the proposed technique.
PY - 2007///
DO - 10.1007/978-3-540-72606-7_92
SP - 1072–1083
PB - Springer
SN - 9783540726050 9783540726067
SV - 4479
UR - http://dx.doi.org/10.1007/978-3-540-72606-7_92
ER -
TY - JOUR
TI - Exact expected values of variance estimators for simulation
AU - Aktaran-Kalaycı, Tûba
AU - Alexopoulos, Christos
AU - Argon, Nilay Tanık
AU - Goldsman, David
AU - Wilson, James R.
T2 - Naval Research Logistics
AB - Abstract We formulate exact expressions for the expected values of selected estimators of the variance parameter (that is, the sum of covariances at all lags) of a steady‐state simulation output process. Given in terms of the autocovariance function of the process, these expressions are derived for variance estimators based on the simulation analysis methods of nonoverlapping batch means, overlapping batch means, and standardized time series. Comparing estimator performance in a first‐order autoregressive process and the M / M /1 queue‐waiting‐time process, we find that certain standardized time series estimators outperform their competitors as the sample size becomes large. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007
DA - 2007///
PY - 2007///
DO - 10.1002/nav.20215
VL - 54
IS - 4
SP - 397-410
J2 - Naval Research Logistics
LA - en
OP -
SN - 0894-069X 1520-6750
UR - http://dx.doi.org/10.1002/nav.20215
DB - Crossref
KW - simulation
KW - stationary process
KW - variance estimation
KW - nonoverlapping batch means
KW - overlapping batch means
KW - standardized time series
ER -
TY - JOUR
TI - Analysis of Network Revenue Management under Uncertainty
AU - Xu, Y.
AU - Fang, S.
AU - Feng, Y.
T2 - Nonlinear Dynamics and Systems Theory
DA - 2007///
PY - 2007///
VL - 7
IS - 1
SP - 85–96
ER -
TY - CONF
TI - Considering Demand Variability and Measurement Uncertainties in Adaptive Source Characterization in Water Distribution Networks
AU - Liu, Li
AU - Brill, Jr., E. Downey
AU - Mahinthakumar, G.
AU - Uber, James
AU - Zechman, Emily M.
AU - Ranjithan, S.
T2 - World Environmental and Water Resources Congress 2007
AB - Characterizing the sources of contamination in water distribution networks continues to be a challenging problem. Several methods have been reported to address this problem. The authors previously presented and continue to investigate an adaptive search procedure that attempts to solve this problem under dynamic conditions. Since demand variability and measurement errors contribute significantly to the quality of the solutions obtained as well as the time to solve the problem, we investigate these effects on the adaptive dynamic optimization procedure. First, the effects of these variabilities and uncertainties on the solutions obtained under deterministic conditions are evaluated. Second, we incorporate them such that the search for the source characterization is conducted under noisy conditions. This paper reports the results from these investigations based on an investigation conducted for an illustrative water distribution network.
C2 - 2007/5/11/
C3 - World Environmental and Water Resources Congress 2007
DA - 2007/5/11/
DO - 10.1061/40927(243)502
PB - American Society of Civil Engineers
SN - 9780784409275
UR - http://dx.doi.org/10.1061/40927(243)502
DB - Crossref
ER -
TY - JOUR
TI - Robust receding horizon control for constrained linear fractional transformation parameter-dependent systems
AU - Wu, F.
AU - Chen, Y.
T2 - IET Control Theory & Applications
AB - A robust receding horizon control (RHC) scheme is proposed for parameter-dependent linear systems with linear fractional parameter dependency and input–output constraints. The cost function is defined over a moving finite horizon as the quadratic performance for future parameter trajectories. The robust stability of the proposed RHC scheme is guaranteed using a parameter-dependent control Lyapunov function as the terminal penalty term, which is available through off-line synthesis procedure. Moreover, it is shown that the domain of attraction will be enlarged and the controlled performance of the RHC scheme will be gradually improved as the upper bound of performance is monotonically decreasing on-line. Both off-line robust control synthesis and on-line RHC computation are formulated and solved using linear matrix inequality optimisation techniques.
DA - 2007/9/1/
PY - 2007/9/1/
DO - 10.1049/iet-cta:20060305
VL - 1
IS - 5
SP - 1423-1430
LA - en
OP -
SN - 1751-8644 1751-8652
UR - http://dx.doi.org/10.1049/iet-cta:20060305
DB - Crossref
ER -
TY - JOUR
TI - An augmented immersed interface-level set method for Stokes equations with discontinuous viscosity
AU - Li, Zhilin
AU - Lubkin, S.
AU - Wan, X.
T2 - Electronic Journal of Differential Equations, Conference
DA - 2007///
PY - 2007///
VL - 15
SP - 193–210
SN - 1072-6691
ER -
TY - BOOK
TI - Applied Numerical Mathematics for the International Conference on Scientific Computing
A3 - Li, Zhilin
DA - 2007///
PY - 2007///
VL - 57
M3 - Special Issues
PB - American Mathematical Society
ER -
TY - MGZN
TI - First SIAG linear algebra school slated for July 2008
AU - Ipsen, I.C.F.
T2 - SIAM News
DA - 2007/11/3/
PY - 2007/11/3/
VL - 40
M1 - 9
ER -
TY - JOUR
TI - Incorporating manufacturing lead times in joint production-marketing models: A review and some future directions
AU - Upasani, Abhijit
AU - Uzsoy, Reha
T2 - Annals of Operations Research
DA - 2007/12/6/
PY - 2007/12/6/
DO - 10.1007/s10479-007-0294-x
VL - 161
IS - 1
SP - 171-188
J2 - Ann Oper Res
LA - en
OP -
SN - 0254-5330 1572-9338
UR - http://dx.doi.org/10.1007/s10479-007-0294-x
DB - Crossref
KW - production/marketing interface
KW - dynamic price and lead time quotation
KW - load dependent lead time
ER -
TY - BOOK
TI - Special Issue for the International Conference on Scientific Computing
DA - 2007/5//
PY - 2007/5//
UR - https://www.sciencedirect.com/journal/applied-numerical-mathematics/vol/57/issue/5
ER -
TY - BOOK
TI - Moving Interface Problems and Applications in Fluid Dynamics
DA - 2007///
PY - 2007///
UR - https://books.google.com/books/about/Moving_Interface_Problems_and_Applicatio.html?id=fMYbCAAAQBAJ
ER -
TY - JOUR
TI - Multiscale Considerations in Modeling of Nonlinear Elastomers
AU - Banks, H. T.
AU - Medhin, Negash G.
AU - Pinter, Gabriella A.
T2 - International Journal for Computational Methods in Engineering Science and Mechanics
AB - We present a survey of results from an extended project focused on the understanding of the dynamic behavior of elastomers or filled rubbers. This entailed experimental, modeling, computational and theoretical efforts. Of particular emphasis are the nonlinear and hysteretic aspects of dynamic deformations.
DA - 2007/2/13/
PY - 2007/2/13/
DO - 10.1080/15502280601149346
VL - 8
IS - 2
SP - 53-62
J2 - International Journal for Computational Methods in Engineering Science and Mechanics
LA - en
OP -
SN - 1550-2287 1550-2295
UR - http://dx.doi.org/10.1080/15502280601149346
DB - Crossref
KW - Nonlinear Partial Differential Equations
KW - Computational Methods
KW - Viscoelasticity
KW - Hysteresis
KW - Molecular Dynamics
KW - Multiscale Modeling
ER -
TY - JOUR
TI - Matching and stabilization of discrete mechanical systems
AU - Bloch, Anthony M.
AU - Leok, Melvin
AU - Marsden, Jerrold E.
AU - Zenkov, Dmitry V.
T2 - PAMM
AB - Abstract Controlled Lagrangian and matching techniques are developed for the stabilization of equilibria of discrete mechanical systems with symmetry as well as broken symmetry. Interesting new phenomena arise in the controlled Lagrangian approach in the discrete context that are not present in the continuous theory. Specifically, a nonconservative force that is necessary for matching in the discrete setting is introduced. The paper also discusses digital and model predictive controllers. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
DA - 2007/12//
PY - 2007/12//
DO - 10.1002/pamm.200700390
VL - 7
IS - 1
SP - 1030603-1030604
J2 - Proc. Appl. Math. Mech.
LA - en
OP -
SN - 1617-7061 1617-7061
UR - http://dx.doi.org/10.1002/pamm.200700390
DB - Crossref
ER -
TY - CHAP
TI - Clustering for Hierarchical Traffic Grooming in Large Scale Mesh WDM Networks
AU - Chen, Bensong
AU - Dutta, Rudra
AU - Rouskas, George N.
T2 - Optical Network Design and Modeling
AB - We present a clustering algorithm for hierarchical traffic grooming in large WDM networks. In hierarchical grooming, the network is decomposed into clusters, and one hub node in each cluster is responsible for grooming traffic from and to the cluster. Hierarchical grooming scales to large network sizes and facilitates the control and management of traffic and network resources. Yet determining the size and composition of clusters so as to yield good grooming solutions is a challenging task. We identify the grooming-specific factors affecting the selection of clusters, and we develop a parameterized clustering algorithm that can achieve a desired tradeoff among various goals.KeywordsProblem InstanceWavelength AssignmentLogical TopologyPhysical TopologyElectronic PortThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
PY - 2007/7/20/
DO - 10.1007/978-3-540-72731-6_28
SP - 249-258
OP -
PB - Springer Berlin Heidelberg
SN - 9783540727293
UR - http://dx.doi.org/10.1007/978-3-540-72731-6_28
DB - Crossref
ER -
TY - CONF
TI - Public logistics network protocol design and implementation
AU - Ling, X.
AU - Kay, M.G.
AU - Telford, J.
C2 - 2007///
C3 - IIE Annual Conference and Expo 2007 - Industrial Engineering's Critical Role in a Flat World - Conference Proceedings
DA - 2007///
SP - 1593-1598
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-44949150426&partnerID=MN8TOARS
ER -
TY - CONF
TI - A comparison of meta-heuristics for large scale facility location problems with economies of scale
AU - Bucci, M.J.
AU - Kay, M.G.
AU - Warsing, D.P.
C2 - 2007///
C3 - IIE Annual Conference and Expo 2007 - Industrial Engineering's Critical Role in a Flat World - Conference Proceedings
DA - 2007///
SP - 1410-1415
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-44949149427&partnerID=MN8TOARS
ER -
TY - CONF
TI - High-contrast algorithm behavior
AU - Stallmann, Matthias F.
AU - Brglez, Franc
T2 - the 2007 workshop
AB - After extensive experiments with two algorithms, CPLEX and our implementation of all-integer dual simplex, we observed extreme differences between the two on a set of design automation benchmarks. In many cases one of the two would find an optimal solution within seconds while the other timed out at one hour.
C2 - 2007///
C3 - Proceedings of the 2007 workshop on Experimental computer science - ExpCS '07
DA - 2007///
DO - 10.1145/1281700.1281712
PB - ACM Press
SN - 9781595937513
UR - http://dx.doi.org/10.1145/1281700.1281712
DB - Crossref
ER -
TY - JOUR
TI - Environmental management systems and green supply chain management: complements for sustainability?
AU - Darnall, Nicole
AU - Jolley, G. Jason
AU - Handfield, Robert
T2 - Business Strategy and the Environment
AB - Some researchers question the legitimacy of EMSs since organizations can claim to have one when in fact they make no attempt to reduce their environmental harm. In instances where EMSs enhance an organization's environmental performance, critics argue that improvements are likely to occur within the organization's operational boundaries rather than being extended throughout the supply chain. However, previous research suggests that the organizational capabilities required to adopt an EMS may facilitate GSCM implementation and the institutional pressures to adopt both management practices are similar. Consequently, EMS adopters may have a greater propensity to expand their focus beyond their organizational boundaries and utilize GSCM practices to minimize system-wide environmental impacts. This research illuminates the debate by empirically evaluating the relationship between EMS and GSCM practices. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment.
DA - 2007///
PY - 2007///
DO - 10.1002/bse.557
VL - 17
IS - 1
SP - 30-45
J2 - Bus. Strat. Env.
LA - en
OP -
SN - 0964-4733 1099-0836
UR - http://dx.doi.org/10.1002/bse.557
DB - Crossref
ER -
TY - CHAP
TI - On the Resilient Overlay Topology Formation in Multi-hop Wireless Networks
AU - Xing, Fei
AU - Wang, Wenye
T2 - NETWORKING 2007. Ad Hoc and Sensor Networks, Wireless Networks, Next Generation Internet
AB - In this paper, we study the problem of how to design overlay topologies in multi-hop wireless networks such that the overlays achieve perfect resilience, in terms of all cooperative nodes included but misbehaving nodes excluded, and preserve the k-connectivity with high probability. To address this problem, we propose a new distributed topology control protocol called PROACtive. By using PROACtive, every node pro-actively selects its cooperative adjacent nodes as neighbors by mutually exchanging neighbor request and reply messages. As a result, the union of all neighbor sets forms a resilient overlay for a given network. Our analysis finds that the PROACtive protocol is light-weighted with the message complexity of only O(m), where m is the number of links in the original network. Our simulation results validate the effectiveness of PROACtive and show that the overlays generated by our protocol preserve the k-connectivity with high probability (> 90%) and low false positive ratio (< 5%).
PY - 2007///
DO - 10.1007/978-3-540-72606-7_1
SP - 1-12
OP -
PB - Springer Berlin Heidelberg
SN - 9783540726050 9783540726067
UR - http://dx.doi.org/10.1007/978-3-540-72606-7_1
DB - Crossref
ER -
TY - JOUR
TI - Supply chain optimisation and protocol environment (SCOPE) for rapid prototyping and analysis of complex supply chains
AU - Orcun, S.
AU - Asmundsson, J. M.
AU - Uzsoy, R.
AU - Clement, J. P.
AU - Pekny, J. F.
AU - Rardin, R. L.
T2 - Production Planning & Control
AB - There is a strong need for modelling tools that allow decision makers to rapidly develop aggregate models of supply chains, including both material and information flow, that they can use to gain insights and assess alternative configurations. We present a prototype implementation of such a system and apply it to a simple supply chain for validation purposes, and to a real world case study from the consumer packaged goods industry.
DA - 2007/6/25/
PY - 2007/6/25/
DO - 10.1080/09537280701417116
VL - 18
IS - 5
SP - 388-406
J2 - Production Planning & Control
LA - en
OP -
SN - 0953-7287 1366-5871
UR - http://dx.doi.org/10.1080/09537280701417116
DB - Crossref
KW - supply chain modelling
KW - non-linear dynamics
KW - agents
KW - collaboration
KW - capacitated systems
KW - aggregate production planning
ER -
TY - JOUR
TI - A single-product network design model with lead time and safety stock considerations
AU - Sourirajan, Karthik
AU - Ozsen, Leyla
AU - Uzsoy, Reha
T2 - IIE Transactions
AB - Most existing network design and facility location models have focused on the trade-off between the fixed costs of locating facilities and variable transportation costs between facilities and customers. However, operational performance measures such as service levels and lead times are what motivates customers to bring business to a company and should be considered in the design of a distribution network. While some previous work has considered lead times and safety stocks separately, they are closely related in practice, since safety stocks are often set relative to the distribution of demand over the lead time. In this paper we consider a two-stage supply chain with a production facility that replenishes a single product at retailers. The objective is to locate Distribution Centers (DCs) in the network such that the sum of the location and inventory (pipeline and safety stock) costs is minimized. The replenishment lead time at the DCs depends on the volume of flow through the DC. We require the DCs to carry enough safety stock to maintain the prescribed service levels at the retailers they serve. The explicit modeling of the relationship between the flows in the network, lead times and safety stocks allows us to capture the trade-off between them. We develop a Lagrangian heuristic to obtain near-optimal solutions with reasonable computational requirements for large problem instances.
DA - 2007/2/26/
PY - 2007/2/26/
DO - 10.1080/07408170600941631
VL - 39
IS - 5
SP - 411-424
J2 - IIE Transactions
LA - en
OP -
SN - 0740-817X 1545-8830
UR - http://dx.doi.org/10.1080/07408170600941631
DB - Crossref
KW - location-inventory model
KW - congestion
KW - service level
KW - Lagrangian relaxation
ER -
TY - JOUR
TI - A genetic algorithm for minimizing maximum lateness on parallel identical batch processing machines with dynamic job arrivals and incompatible job families
AU - Malve, Sujay
AU - Uzsoy, Reha
T2 - Computers & Operations Research
AB - We consider the problem of minimizing maximum lateness on parallel identical batch processing machines with dynamic job arrivals. We propose a family of iterative improvement heuristics based on previous work by Potts [Analysis of a heuristic for one machine sequencing with release dates and delivery times. Operations Research 1980;28:1436-41] and Uzsoy [Scheduling batch processing machines with incompatible job families. International Journal for Production Research 1995;33(10):2685-708] and combine them with a genetic algorithm (GA) based on the random keys encoding of Bean [Genetic algorithms and random keys for sequencing and optimization. ORSA Journal on Computing 1994;6(2):154-60]. Extensive computational experiments show that one of the proposed GAs runs significantly faster than the other, providing a good tradeoff between solution time and quality. The combination of iterative heuristics with GAs consistently outperforms the iterative heuristics on their own.
DA - 2007/10//
PY - 2007/10//
DO - 10.1016/j.cor.2005.11.011
VL - 34
IS - 10
SP - 3016-3028
J2 - Computers & Operations Research
LA - en
OP -
SN - 0305-0548
UR - http://dx.doi.org/10.1016/j.cor.2005.11.011
DB - Crossref
KW - batch processing machines
KW - scheduling
KW - genetic algorithms
KW - heuristics
ER -
TY - JOUR
TI - Hybrid decomposition heuristics for solving large-scale scheduling problems in semiconductor wafer fabrication
AU - Sourirajan, Karthik
AU - Uzsoy, Reha
T2 - Journal of Scheduling
DA - 2007/2//
PY - 2007/2//
DO - 10.1007/s10951-006-0325-5
VL - 10
IS - 1
SP - 41-65
J2 - J Sched
LA - en
OP -
SN - 1094-6136 1099-1425
UR - http://dx.doi.org/10.1007/s10951-006-0325-5
DB - Crossref
KW - job shop scheduling
KW - maximum lateness
KW - shifting bottleneck
KW - vomputational evaluation
ER -
TY - JOUR
TI - Lagrangian heuristics for scheduling new product development projects in the pharmaceutical industry
AU - Varma, Vishal A.
AU - Uzsoy, Reha
AU - Pekny, Joseph
AU - Blau, Gary
T2 - Journal of Heuristics
DA - 2007/4/27/
PY - 2007/4/27/
DO - 10.1007/s10732-007-9016-4
VL - 13
IS - 5
SP - 403-433
J2 - J Heuristics
LA - en
OP -
SN - 1381-1231 1572-9397
UR - http://dx.doi.org/10.1007/s10732-007-9016-4
DB - Crossref
KW - resource constrained multi-project scheduling
KW - dual block angular matrix
KW - lagrangian dual
KW - decomposition
KW - integer programming
ER -
TY - JOUR
TI - Outbound supply chain network design with mode selection and lead time considerations
AU - Eskigun, Erdem
AU - Uzsoy, Reha
AU - Preckel, Paul V.
AU - Beaujon, George
AU - Krishnan, Subramanian
AU - Tew, Jeffrey D.
T2 - Naval Research Logistics
AB - We present a large-scale network design model for the outbound supply chain of an automotive company that considers transportation mode selection (road vs. rail) and explicitly models the relationship between lead times and the volume of flow through the nodes of the network. We formulate the problem as a nonlinear zero-one integer program, reformulate it to obtain a linear integer model, and develop a Lagrangian heuristic for its solution that gives near-optimal results in reasonable time. We also present scenario analyses that examine the behavior of the supply chain under different parameter settings and the performance of the solution procedures under different experimental conditions. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2007
DA - 2007///
PY - 2007///
DO - 10.1002/nav.20205
VL - 54
IS - 3
SP - 282-300
J2 - Naval Research Logistics
LA - en
OP -
SN - 0894-069X 1520-6750
UR - http://dx.doi.org/10.1002/nav.20205
DB - Crossref
KW - supply chain
KW - network design
KW - Lagrangian heuristic
ER -
TY - CONF
TI - Evaluation of Non-Uniqueness in Contaminant Source Characterization Based on Sensors with Event Detection Methods
AU - Kumar, Jitendra
AU - Zechman, E. M.
AU - Brill, E. D.
AU - Mahinthakumar, G.
AU - Ranjithan, S.
AU - Uber, J.
T2 - World Environmental and Water Resources Congress 2007
AB - Due to the present state of sensor technology, during a water distribution contamination event, sensors may be able to detect only the presence of a contaminant and not necessarily the complete concentration profile. Some sensors trigger a detection based on a specified threshold concentration of observation, yielding a binary detection/no-detection signal. Event detection can also be based on observed concentrations of water quality parameters, such as pH and chlorine, which are routinely measured. These concentration observations are then processed through event detection algorithms to yield a detection/no-detection signal. These event detection techniques filter the measured concentrations at sensors to produce a discrete signal. When using this filtered information to characterize the contamination source, the certainty of identifying a unique solution is likely reduced, i.e., a set of widely different source characteristics may provide a match for the sensor observations. The authors previously presented an evolutionary algorithm-based procedure for source characterization and for assessing non-uniqueness by generating a set of maximally different alternatives. The procedure is extended here to characterize a contaminant source and any non-uniqueness arising by using sensor information processed through different event detection methods.
C2 - 2007/5/11/
C3 - World Environmental and Water Resources Congress 2007
DA - 2007/5/11/
DO - 10.1061/40927(243)513
PB - American Society of Civil Engineers
SN - 9780784409275
UR - http://dx.doi.org/10.1061/40927(243)513
DB - Crossref
ER -
TY - CHAP
TI - Cyberinfrastructure for Contamination Source Characterization in Water Distribution Systems
AU - Sreepathi, Sarat
AU - Mahinthakumar, Kumar
AU - Zechman, Emily
AU - Ranjithan, Ranji
AU - Brill, Downey
AU - Ma, Xiaosong
AU - von Laszewski, Gregor
T2 - Computational Science – ICCS 2007
AB - This paper describes a preliminary cyberinfrastructure for contaminant characterization in water distribution systems and its deployment on the grid. The cyberinfrastructure consists of the application, middleware and hardware resources. The application core consists of various optimization modules and a simulation module. This paper focuses on the development of specific middleware components of the cyberinfrastructure that enables efficient seamless execution of the application core in a grid environment. The components developed in this research include: (i) a coarse-grained parallel wrapper for the simulation module that includes additional features for persistent execution, (ii) a seamless job submission interface, and (iii) a graphical real time application monitoring tool. The performance of the cyberinfrastructure is evaluated on a local cluster and the TeraGrid.
PY - 2007///
DO - 10.1007/978-3-540-72584-8_139
SP - 1058-1065
OP -
PB - Springer Berlin Heidelberg
SN - 9783540725831 9783540725848
UR - http://dx.doi.org/10.1007/978-3-540-72584-8_139
DB - Crossref
ER -
TY - JOUR
TI - Shape derivatives without taking the shape derivative
AU - Ito, K.
AU - Kunisch, K.
AU - Peichl, G.
T2 - PAMM
AB - Abstract A general framework for calculating shape derivatives for optimization problems with partial differential equations as constraints is presented. Exploiting the structure of the cost functional the proposed technique allows to obtain the shape derivative of the cost without the necessity to involve the shape derivative of the state variable. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
DA - 2007/12//
PY - 2007/12//
DO - 10.1002/pamm.200700780
VL - 7
IS - 1
SP - 1061005-1061006
J2 - Proc. Appl. Math. Mech.
LA - en
OP -
SN - 1617-7061 1617-7061
UR - http://dx.doi.org/10.1002/pamm.200700780
DB - Crossref
ER -
TY - JOUR
TI - An immersed interface method for the Navier-Stokes equations on irregular domains
AU - Li, Zhilin
AU - Lai, Ming-Chih
AU - Ito, Kazufumi
T2 - PAMM
AB - Abstract An augmented method based on a Cartesian grid is proposed for the incompressible Navier Stokes equations on an irregular domain. The irregular domain is embedded into a rectangular one so that a fast Poisson solver can be used in the projection method. Unlike several methods suggested in the literature that set the force strengths as unknowns, which often results an ill‐conditioned linear system, we set the jump in the normal derivative of the velocity as the augmented variable. The new approach improve the condition number of the system for the augmented variable significantly. Using the immersed interface method, we achieve second order accuracy for the velocity. Numerical results and comparisons are given to validate the new method. Some interesting new numerical experiments results are also presented. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
DA - 2007/12//
PY - 2007/12//
DO - 10.1002/pamm.200700758
VL - 7
IS - 1
SP - 1025401-1025402
J2 - Proc. Appl. Math. Mech.
LA - en
OP -
SN - 1617-7061 1617-7061
UR - http://dx.doi.org/10.1002/pamm.200700758
DB - Crossref
ER -
TY - JOUR
TI - Simulation of Fusion Plasmas: Current Status and Future Direction
AU - Batchelor, D A
AU - Beck, M
AU - Becoulet, A
AU - Budny, R V
AU - Chang, C S
AU - Diamond, P H
AU - Dong, J Q
AU - Fu, G Y
AU - Fukuyama, A
AU - Hahm, T S
AU - Keyes, D E
AU - Kishimoto, Y
AU - Klasky, S
AU - Lao, L L
AU - Li, K
AU - Lin, Z
AU - Ludaescher, B
AU - Manickam, J
AU - Nakajima, N
AU - Ozeki, T
AU - Podhorszki, N
AU - Tang, W M
AU - Vouk, M A
AU - Waltz, R E
AU - Wang, S J
AU - Wilson, H R
AU - Xu, X Q
AU - Yagi, M
AU - Zonca, F
T2 - Plasma Science and Technology
AB - I. Introduction (Z. Lin, G. Y. Fu, J. Q. Dong) II. Role of theory and simulation in fusion sciences 1. The Impact of theory and simulation on tokomak experiments (H. R. Wilson, T.S. Hahm and F. Zonca) 2. Tokomak Transport Physics for the Era of ITER: Issues for Simulations (P.H. Diamond and T.S. Hahm) III. Status of fusion simulation and modeling 1. Nonlinear Governing Equations for Plasma Simulations (T. S. Hahm) 2. Equilibrium and stability (L.L. Lao, J. Manickam) 3. Transport modeling (R.E. Waltz) 4. Nonlinear MHD (G.Y. Fu) 5. Turbulence (Z. Lin and R.E. Waltz) 6. RF heating and current drive (D.A. Batchelor) 7. Edge physics Simulations (X.Q. Xu and C.S. Chang) 8. Energetic particle physics (F. Zonca, G.Y. Fu and S.J. Wang) 9. Time-dependent Integrated Modeling (R.V. Budny) 10. Validation and verification (J. Manickam) IV. Major initiatives on fusion simulation 1. US Scientific Discovery through Advanced Computing (SciDAC) Program & Fusion Energy Science (W. Tang) 2. EU Integrated Tokamak Modelling (ITM) Task Force (A. Becoulet) 3. Fusion Simulations Activities in Japan (A. Fukuyama, N. Nakajima, Y. Kishimoto, T. Ozeki, and M. Yagi) V. Cross-disciplinary research in fusion simulation 1. Applied mathematics: Models, Discretizations, and Solvers (D.E. Keyes) 2. Computational Science (K. Li) 3. Scientific Data and Workflow Management (S. Klasky, M. Beck, B. Ludaescher, N. Podhorszki, M.A. Vouk) 4. Collaborative tools (J. Manickam)
DA - 2007/6//
PY - 2007/6//
DO - 10.1088/1009-0630/9/3/13
VL - 9
IS - 3
SP - 312-387
J2 - Plasma Sci. Technol.
OP -
SN - 1009-0630
UR - http://dx.doi.org/10.1088/1009-0630/9/3/13
DB - Crossref
ER -
TY - CHAP
TI - Automation of Network-Based Scientific Workflows
AU - Vouk, M. A.
AU - Altintas, I.
AU - Barreto, R.
AU - Blondin, J.
AU - Cheng, Z.
AU - Critchlow, T.
AU - Khan, A.
AU - Klasky, S.
AU - Ligon, J.
AU - Ludaescher, B.
AU - Mouallem, P. A.
AU - Parker, S.
AU - Podhorszki, N.
AU - Shoshani, A.
AU - Silva, C.
T2 - IFIP The International Federation for Information Processing
AB - Comprehensive, end-to-end, data and workflow management solutions are needed to handle the increasing complexity of processes and data volumes associated with modern distributed scientific problem solving, such as ultrascale simulations and high-throughput experiments. The key to the solution is an integrated network-based framework that is functional, dependable, faulttolerant, and supports data and process provenance. Such a framework needs to make development and use of application workflows dramatically easier so that scientists’ efforts can shift away from data management and utility software development to scientific research and discovery. An integrated view of these activities is provided by the notion of scientific workflows - a series of structured activities and computations that arise in scientific problem-solving. An information technology framework that supports scientific workflows is the Ptolemy II based environment called Kepler. This paper discusses the issues associated with practical automation of scientific processes and workflows and illustrates this with workflows developed using the Kepler framework and tools.
PY - 2007/11/16/
DO - 10.1007/978-0-387-73659-4_3
SP - 35-61
OP -
PB - Springer US
SN - 9780387736587
UR - http://dx.doi.org/10.1007/978-0-387-73659-4_3
DB - Crossref
ER -
TY - JOUR
TI - Some software aspects of DAE simulation & optimization software
AU - Campbell, S. L.
AU - Betts, J. T.
AU - Engelsone, A.
AU - Nikoukhah, R.
AU - Najafi, M.
T2 - PAMM
AB - Abstract Considerable numerical software has been written for simulation and optimization of dynamical systems. From the beginning of their development, differential algebraic equations (DAEs) have often been proposed as a way to make modeling easier. The modeler need only write down equations relating the variables in the model. However, much DAE software requires at least as much user numerical and mathematical expertise as explicit methods. An important aspect of our research has been working toward helping the idea of DAEs achieve its promise in modeling and simulation by both pushing the software to handle more general problems and to also allow for less user expertise. Some recent examples are presented where this research impacts on software and their underlying algorithms. Space necessitates we assume the reader has a rough idea of what a DAE is. The examples are implicit Scicos, and optimization of DAE models. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
DA - 2007/12//
PY - 2007/12//
DO - 10.1002/pamm.200700495
VL - 7
IS - 1
SP - 1023103-1023104
SN - 1617-7061 1617-7061
UR - http://dx.doi.org/10.1002/pamm.200700495
ER -
TY - JOUR
TI - Problems and techniques: Introduction
AU - Ipsen, I.
T2 - SIAM Review
DA - 2007///
PY - 2007///
VL - 49
IS - 4
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-37249005235&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Problems and techniques
AU - Ipsen, I.
T2 - SIAM Review
DA - 2007///
PY - 2007///
VL - 49
IS - 2
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-34249999151&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Problems and Techniques
AU - Ipsen, Ilse
T2 - SIAM Review
AB - The three papers in this issue deal with how to describe spikes and plateaus; how to bound the probability that a random variable belongs to a particular set; and how to analyze thermodynamic properties of DNA and RNA. 1. If you had only a (mathematical) sound bite to explain the difference between the broad plateau of the Black Mesa in Arizona and the steep spike of the Matterhorn in Switzerland, what could you do? Thomas Hillen, in his paper “A Classification of Spikes and Plateaus,” proposes that you inspect fourth derivatives. In Flatland (a one‐dimensional domain, that is), the Black Mesa has a negative fourth derivative at its highest point, while the Matterhorn has a positive fourth derivative. For n‐dimensional domains it’s a little bit more complicated because one has to check whether the Hessian of the Laplacian is positive definite or negative definite. The author illustrates how the classification of plateaus and spikes benefits the qualitative analysis of several partial differential equations from mathematical physics and biology. 2. Given a random vector $X\in\real^n$ whose first two moments (the expected mean vector $\mathbf{E}X$ and the covariance matrix $\mathbf{E}XX^T$) are known, the problem considered in the second paper is to bound the probability that X lies in a particular subset C of $\real^n$. Here the set C is defined by m strict quadratic inequalities, $$C=\left\{x\in\real^n:\ x_i^TA_ix+2b_i^Tx+c_i<0, \quad 1\leq i\leq m\right\},$$ which involve symmetric matrices $A_i$, vectors $b_i$, and scalars $c_i$. The best possible (“sharp”) lower bound on the probability that X lies in C is an example of a generalized Chebyshev inequality. In general, generalized Chebyshev inequalities are sharp upper or lower bounds on the probability that a random vector with given moments lies in a particular set. The first such inequality was formulated in the nineteenth century by Chebyshev and proved by his student Markov. Almost a hundred years later duality theory and optimization emerged as powerful tools for deriving Chebyshev inequalities. Since then Chebyshev inequalities have appeared in decision analysis, statistics, finance, and machine learning. In their well‐written paper “Generalized Chebyshev Bounds via Semidefinite Programming,” Lieven Vandenberghe, Stephen Boyd, and Katherine Comanor construct two equivalent (dual) semidefinite programs for solving the above Chebyshev inequality. That is, the optimal value of these programs equals the best possible lower bound on the probability that a random vector X with given mean and covariance lies in the set C. If you have time, savor the well‐organized and constructive proofs, and check out the two simple examples to watch the semidefinite programs in action. 3. Nucleic acid technology is based on the design of molecular systems that self‐assemble out of strands of DNA or RNA, so as to implement functions relevant to robotics, biosensing, medicine, and many other applications. Fundamental to the success of this technology is a rigorous analysis of the thermodynamic properties of nucleic acid strands. In their paper “Thermodynamic Analysis of Interacting Nucleic Acid Strands,” Robert Dirks, Justin Bois, Joseph Schaeffer, Erik Winfree, and Niles Pierce make a significant advance by devising models and algorithms, not just for a single strand, but for an entire test tube of interacting strands of nucleic acids. They do this by combining an unusual variety of different mathematical techniques. A nucleic acid strand can be represented as a sequence of bases from a four‐letter alphabet (for DNA the bases are A, C, G, and T). Complementary bases can interact to form base pairs (for DNA these base pairs are C‐G and A‐T). The set of base pairs in a molecular conformation of interacting nucleic acid strands is called the secondary structure. In the simplest case, two fully‐complementary strands can base‐pair to each other completely, bringing to mind a ladder in which the rungs represent base pairs and the two sides of the ladder represent the backbones of the two strands. In practice, however, things are usually more complicated. Not every base is paired, and the strands might interact to form branched structures with various types of bulges and loops between the base pairs. For reasons of practicality, the authors disallow certain complicated secondary structures (pseudoknots). An important thermodynamic property, useful for the design of nucleic acids, is the equilibrium probability of a secondary structure. It can be calculated in a straightforward way from the partition function. Calculating the partition function for a single strand requires summing the partition functions of all smaller subsequences. This can be done by a dynamic program that computes the sums recursively. By contrast, calculating the partition function for a complex of several interacting strands is much more difficult, due to the physical and mathematical issues that arise when bases from different strands pair up. The authors present models and algorithms for computing the partition function for a complex of an arbitrary number of interacting strands. In particular, they use graph theory to map each allowed secondary structure to a unique ordering of strands (representation theorem). And they use group theory to eliminate symmetries and redundancies that would lead to overestimates of the partition function (distinguishability correction). Together, these results ensure that a dynamic program can again be used to recursively calculate the partition function. Now the authors are ready to extend their analysis to realistic experimental conditions where an arbitrary number of strand species interact (in a dilute solution) to form a variety of complexes. The authors use combinatorial arguments to determine how many times the dynamic program must be invoked to compute the partition function for such a system. They express the computation of the equilibrium concentration of each species of complex as a convex programming problem and use the concave dual problem as the basis for an efficient numerical implementation.
DA - 2007/1//
PY - 2007/1//
DO - 10.1137/siread000049000001000033000001
VL - 49
IS - 1
SP - 33-34
ER -
TY - JOUR
TI - Problems and Techniques
AU - Ipsen, Ilse
T2 - SIAM Review
DA - 2007/1//
PY - 2007/1//
DO - 10.1137/siread000049000002000209000001
VL - 49
IS - 2
SP - 209-209
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-34548494833&partnerID=MN8TOARS
ER -
TY - CONF
TI - Computer optimization of electron gun designs
AU - Ives, R.L.
AU - Bui, Thuc
AU - David, J.
AU - Tran, Hien
AU - Read, M.
T2 - 2007 Joint 32nd International Conference on Infrared and Millimeter Waves and the 15th International Conference on Terahertz Electronics (IRMMW-THz)
AB - Computer optimization is applied to three dimensional design of electron guns. The resulting designs exhibit improved performance with significantly reduced design cost compared to manual design. Design tables update geometric parameters in a solid modeling program, including dimensions for points defining spline surfaces. Algorithms then modified the geometry and other parameters based on goal functions defining the desired performance. Optimal designs were achieved by automatic execution of the optimization loop. Results for confined flow Pierce guns, sheet beam guns, and multiple beam guns will be described.
C2 - 2007/9//
C3 - 2007 Joint 32nd International Conference on Infrared and Millimeter Waves and the 15th International Conference on Terahertz Electronics
DA - 2007/9//
DO - 10.1109/icimw.2007.4516435
PB - IEEE
SN - 9781424414383
UR - http://dx.doi.org/10.1109/icimw.2007.4516435
DB - Crossref
ER -
TY - JOUR
TI - Subset selection for parameter estimation in an HIV model
AU - Fink, Martin
AU - Attarian, Adam
AU - Tran, Hien
T2 - PAMM
AB - Abstract This paper discusses methodologies for subset selection for nonlinear least squares parameter estimation. In particular, we will present approaches for partitioning the parameter space into well‐conditioned and ill‐conditioned subsets. The algorithms are applied to a simplified mathematical model of the physiologic response of the human immunodeficiency virus (HIV) in humans. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
DA - 2007/12//
PY - 2007/12//
DO - 10.1002/pamm.200700319
VL - 7
IS - 1
SP - 1121501-1121502
J2 - Proc. Appl. Math. Mech.
LA - en
OP -
SN - 1617-7061 1617-7061
UR - http://dx.doi.org/10.1002/pamm.200700319
DB - Crossref
ER -
TY -
ER -
TY - CONF
TI - Representing and reasoning about commitments in business processes
AU - Desai, N.
AU - Chopra, A.K.
AU - Singh, M.P.
C2 - 2007///
C3 - Proceedings of the National Conference on Artificial Intelligence
DA - 2007///
VL - 2
SP - 1328-1333
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-36349027545&partnerID=MN8TOARS
ER -
TY - CONF
TI - Toward verification of commitment protocols and their compositions
AU - Desai, N.
AU - Cheng, Z.
AU - Chopra, A.K.
AU - Singh, M.P.
AB - Commitment protocols have been proposed as a basis for modeling and enacting interactions among agents, such as those needed to carry out business processes. A central idea is that protocols would be developed and shared via libraries, and refined and composed to produce protocols that serve specific needs. Success in this program, therefore, presupposes that individual protocols and their compositions can be formally verified with respect to the properties of interest. This paper outlines an approach for verifying the correctness of commitment protocols and their compositions that exploits the well-known software engineering technique of model checking.
C2 - 2007///
C3 - Proceedings of the International Conference on Autonomous Agents
DA - 2007///
DO - 10.1145/1329125.1329165
SP - 144-146
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-60349102464&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Governance of cross-organizational service agreements: A policy-based approach
T2 - IEEE INTERNATIONAL CONFERENCE ON SERVICES COMPUTING, PROCEEDINGS
DA - 2007///
PY - 2007///
UR - https://publons.com/publon/21294458/
ER -
TY - JOUR
TI - Formalizing Communication Protocols for Multiagent Systems
T2 - 20TH INTERNATIONAL JOINT CONFERENCE ON ARTIFICIAL INTELLIGENCE
DA - 2007///
PY - 2007///
UR - https://publons.com/publon/21294460/
ER -
TY - JOUR
TI - Formal Trust Model for Multiagent Systems
T2 - 20TH INTERNATIONAL JOINT CONFERENCE ON ARTIFICIAL INTELLIGENCE
DA - 2007///
PY - 2007///
UR - https://publons.com/publon/21294461/
ER -
TY - CONF
TI - Governance of cross-organizational service agreements: A policy-based approach
AU - Udupi, Y.B.
AU - Singh, M.P.
AB - Many real-life organizations are hierarchies of largely autonomous, heterogeneous members (individuals or other organizations), often exhibiting rich policies. We restrict our attention to organizations that monitor their environment, collate events, determine compliance of their behaviors with their policies, and potentially act in anticipation of events to ensure the satisfaction of their policies. This paper models cross-organizational service agreements as resulting in the formation of organizations. This paper emphasizes the importance of proactive policy-based governance in organizations (modeled as multiagent systems) and provides a novel architecture supporting policy monitoring, governance, and enactment. This paper provides an initial formalization and discusses the compliance and completeness of behaviors produced from specified policies. To demonstrate the practical utility of this approach, it is implemented using an existing policy engine and messaging middleware.
C2 - 2007///
C3 - Proceedings - 2007 IEEE International Conference on Services Computing, SCC 2007
DA - 2007///
DO - 10.1109/SCC.2007.63
SP - 36-43
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-35248815169&partnerID=MN8TOARS
ER -
TY - CONF
TI - Engineering foreign exchange processes via commitment protocols
AU - Desai, N.
AU - Chopra, A.K.
AU - Arrott, M.
AU - Spechte, B.
AU - Singh, M.P.
AB - Foreign exchange (FX) markets see a transaction volume of over $2 trillion per day. A number of standard ways of conducting business have been developed in the FX industry. However, current FX specifications are informal and their business semantics unclear. The resulting implementations tend to be complex and compliance with the standards unverifiable. This results in potential loss of value due to incompatible business processes and possible trades not consummated. This paper validates a formal, protocol-based approach by specifying foreign exchange processes as standardized by the TWIST consortium. The proposed approach formalizes a small, core set of foreign exchange interaction protocols on which the desired processes can be based. The core protocols can be composed to yield a large variety of possible processes. Each protocol is rigorously defined in terms of the commitments undertaken and manipulated by the parties involved. By contrast, traditional approaches as used in the current TWIST specification lead to redundancy in specification and difficulty in understanding the import of the interactions involved. In addition, our approach discovered interesting business scenarios that traditional approaches would have missed.
C2 - 2007///
C3 - Proceedings - 2007 IEEE International Conference on Services Computing, SCC 2007
DA - 2007///
DO - 10.1109/SCC.2007.58
SP - 514-521
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-35248848926&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Logic-Based Agent Verification
AU - Fisher, M.
AU - Singh, M.
AU - Spears, D.
AU - Wooldridge, M.
T2 - Journal of Applied Logic
DA - 2007///
PY - 2007///
DO - 10.1016/j.jal.2005.12.012
VL - 5
IS - 2
SP - 193-195
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-34247135747&partnerID=MN8TOARS
ER -
TY - CONF
TI - InterPol: A policy framework for managing trust and privacy in referral networks
AU - Udupi, Y.B.
AU - Singh, M.P.
AB - Referral networks are a kind of P2P system consisting of autonomous agents who seek, provide services, or refer other service providers. Key applications include service discovery and selection, and knowledge sharing. This use of referrals is inspired by human interactions, where referrals are a key basis for judging the trustworthiness of a given service.The use of referrals enable an agent to control how its request is processed, it also provides an architectural basis for four kinds of interaction policies. InterPol is a language and framework supporting such policies. InterPol has been implemented using a Datalog-based policy engine for each agent. It has been applied on scenarios from a (multinational) health care project. The contribution of this paper is in a general referrals-based framework for privacy and trust management, which is shown to effectively capture a variety of privacy and trust requirements of autonomous users.
C2 - 2007///
C3 - Proceedings of the International Conference on Autonomous Agents
DA - 2007///
DO - 10.1145/1329125.1329332
SP - 1095-1097
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-60349089685&partnerID=MN8TOARS
ER -
TY - CONF
TI - An event-driven approach for agent-based business process enactment
AU - Chakravarty, P.
AU - Singh, M.P.
AB - Agents enacting business processes in large open environments need to adaptively accommodate exceptions. Work on multiagent approaches can flexibly model business processes. This paper proposes an event-driven architecture that enriches such models with events resulting in a more robust and proactive system. Specifically, we place this architecture in a business process framework based on protocols and policies, where agents' behaviors are specified via rules. The contributions of this paper include (1) an event-driven architecture, (2) a specification language that combines event logic with rules and (3) a methodology to incorporate events into a process (such as for fine-grained monitoring), (4) a way to manage subscriptions to simple events efficiently. This approach is applied on a well-known business scenario.
C2 - 2007///
C3 - Proceedings of the International Conference on Autonomous Agents
DA - 2007///
DO - 10.1145/1329125.1329383
SP - 1269-1271
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-60349117905&partnerID=MN8TOARS
ER -
TY - CONF
TI - A modular action description language for protocol composition
AU - Desai, N.
AU - Singh, M.P.
C2 - 2007///
C3 - Proceedings of the National Conference on Artificial Intelligence
DA - 2007///
VL - 2
SP - 962-967
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-36349036553&partnerID=MN8TOARS
ER -
TY - CONF
TI - Enacting protocols by commitment concession
AU - Yolum, P.
AU - Singh, M.P.
AB - Commitment protocols formalize interactions among autonomous, heterogeneous agents, leaving the agents' local policies unspecified. This paper studies the problem of agents enacting commitment protocols, which inherently requires that their policies cohere with the given protocols. Specifically, in many important settings, if agents incautiously create and discharge commitments, they can expose themselves to certain risk; conversely, if the agents are (excessively) cautious, a protocol enactment may deadlock. This paper adopts the well-known idea of monotonic concession, but specializes and enhances it with the particular features of commitments. Specifically, this paper formulates inference rules for commitment concession that respect the nature of commitments. Next, it shows how commitments can be systematically revised as the agents incrementally engage each other in enacting their protocol. This paper demonstrates how such rules can be applied in practice, and identifies conditions under which progress and termination of protocol enactment can be guaranteed.
C2 - 2007///
C3 - Proceedings of the International Conference on Autonomous Agents
DA - 2007///
DO - 10.1145/1329125.1329158
SP - 116-123
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-45449096030&partnerID=MN8TOARS
ER -
TY - CONF
TI - Dynamics of contracts-based organizations: A formal approach based on institutions
AU - Udupi, Y.B.
AU - Singh, M.P.
AB - An organization comprises a group of collaborating agents (individual agents or nested organizations) that exhibit complex behaviors. Of particular interest are dynamic organizations that form and dissolve as their members' needs change. Such organizations are important in many applications, including scientific and business computing. Contracts among autonomous agents have long been used to facilitate their collaboration. This paper provides a contracts-based approach for managing organizations. The proposed approach places organizations within institutions, themselves modeled as specialized organizations. Commitments form the basis of contracts and this paper establishes some important dynamic aspects by providing a commitment life cycle analysis. This approach has been applied in a prototype tool to manage organizations.
C2 - 2007///
C3 - Proceedings of the International Conference on Autonomous Agents
DA - 2007///
DO - 10.1145/1329125.1329149
SP - 82-84
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-60349099664&partnerID=MN8TOARS
ER -
TY - CONF
TI - Choice and interoperation in protocol enactment
AU - Chopra, A.K.
AU - Singh, M.P.
AB - Protocols describe interactions among agents and thus underlie the engineering of multiagent systems. However, protocols are enacted by agents in physical systems. In particular, considerations of communication models and how distributed agents are able to make compatible choices would greatly affect whether a protocol may in fact be enacted successfully. The objective of this paper is to study the conceptual underpinnings of protocol enactment in multiagent systems. It seeks to characterize the operationalization of agents so as to determine whether and when agents may be interoperable.
C2 - 2007///
C3 - Proceedings of the International Conference on Autonomous Agents
DA - 2007///
DO - 10.1145/1329125.1329161
SP - 132-134
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-60349125584&partnerID=MN8TOARS
ER -
TY - RPRT
TI - View and index selection for query-performance improvement: Algorithms, heuristics and complexity
AU - Kormilitsin, Maxim
AU - Chirkova, Rada Y
AU - Fathi, Yahya
AU - Stallmann, Matthias F
A3 - North Carolina State University. Dept. of Computer Science
DA - 2007///
PY - 2007///
PB - North Carolina State University. Dept. of Computer Science
ER -
TY - CONF
TI - Proofchecker: an accessible environment for automata theory correctness proofs
AU - Stallmann, Matthias F
AU - Balik, Suzanne P
AU - Rodman, Robert D
AU - Bahram, Sina
AU - Grace, Michael C
AU - High, Susan D
T2 - ACM
C2 - 2007///
C3 - ACM SIGCSE Bulletin
DA - 2007///
VL - 39
SP - 48-52
M1 - 3
ER -
TY - CONF
TI - High-contrast algorithm behavior: observation, hypothesis, and experimental design
AU - Stallmann, Matthias F
AU - Brglez, Franc
T2 - ACM
C2 - 2007///
C3 - Proceedings of the 2007 workshop on Experimental computer science
DA - 2007///
SP - 12
ER -
TY - JOUR
TI - A case for smaller class size with integrated lab for introductory computer science
AU - Boyer, Kristy Elizabeth
AU - Dwight, Rachael S
AU - Miller, Carolyn S
AU - Raubenheimer, C Dianne
AU - Stallmann, Matthias F
AU - Vouk, Mladen A
T2 - ACM SIGCSE Bulletin
DA - 2007///
PY - 2007///
VL - 39
IS - 1
SP - 341-345
ER -
TY - JOUR
TI - Convergence Analysis of the {DIRECT} Algorithm
AU - Finkel, D E
AU - Kelley, C T
DA - 2007///
PY - 2007///
ER -
TY - JOUR
TI - A Case Study in Using Local {I/O} and {GPFS} to Improve Simulation Scalability
T2 - 8th LCI International Conference on High-Performance Clustered Computing
DA - 2007///
PY - 2007///
ER -
TY - JOUR
TI - Analysis of A Scalable Preconditioner for the Wigner-Poisson Equation
AU - Lasater, M.S.
AU - Kelley, C.T.
AU - Salinger, A.
AU - Woolard, D.L.
AU - Recine, G.
AU - Zhao, P.
T2 - International Journal of Pure and Applied Mathematics
DA - 2007///
PY - 2007///
VL - 37
SP - 247–270
ER -
TY - JOUR
TI - Problems and Techniques
AU - Ipsen, Ilse
T2 - SIAM Review
AB - This issues features papers about mathematical genetics, data compression, and data assimilation in oceanography. 1. Computer algebra can help to predict the genetic makeup of a population. This is what we can conclude from the first paper, “Buchberger's Algorithm and the Two-Locus, Two-Allele Model.” With reproduction rates and probability of chromosome recombination as parameters, and one variable for each chromosome type, one can set up a system of polynomial equations. The solution value for a variable indicates how often this chromosome type occurs in the population. The question is now, over all parameter choices, how many different equilibrium solutions can there be? In other words, in the long term, can a chromosome type occur with any possible frequency? Arthur Copeland's answer is no: the number of solutions is almost always finite (and conjectured to be 15) in the special case when a population contains at most four different chromosome types. He arrives at his answer by means of affine varieties, ideals, and Gröbner bases. He also shows that the equilibrium solutions vary smoothly with the parameters. 2. The second paper, “A Direct Formulation for Sparse PCA Using Semidefinite Programming,” by Alexandre d'Aspremont, Laurent El Ghaoui, Michael I. Jordan, and Gert R. G. Lanckriet, is concerned with principal component analysis (PCA), a technique for compressing data so that as little information as possible is lost. PCA accomplishes this by finding directions of maximum variance in the data. In data analysis of gene expressions, for instance, different elements of a direction vector correspond to different genes. However, interpreting the meaning of a direction is much easier if only a few genes contribute to the direction. Such a direction vector has many zero elements and is called sparse. The authors propose a semidefinite programming method that maximizes variance as well as sparsity. The method is computationally efficient and robust. 3. The topic of the third paper, “A Reduced-Order Kalman Filter for Data Assimilation in Physical Oceanography,” by D. Rozier, F. Birol, E. Cosme, P. Brasseur, J. M. Brankart, and J. Verron, is a technique used by oceanographers to increase the accuracy of numerical models for predicting ocean circulation. Data assimilation combines the output of a simulation step with observed data and error statistics and then returns this “corrected” output to the simulation as the basis for the next step. Data assimilation based on Kalman filters assumes that measurement and model errors are unbiased and Gaussian. This is expensive, however, because an error covariance matrix must be constructed at every step. A reduced-order Kalman filter (called SEEK) is a cheaper version that reduces (or compresses) the size of the covariance matrix—the same key idea as in the paper described above. The authors give a very readable account of the issues associated with so-called ocean global circulation models: choice of vertical coordinate system (depending on the ocean region: shallow coastal shelf, steeply sloping ocean floors, stratified regions); limitations of models for ocean circulation simulations; sequential data assimilation techniques; adaptation of Kalman filters to geophysical applications; and modes of data acquisition (via satellites, ships, floats, mooring networks). The effectiveness of the SEEK filter is illustrated with numerical simulations of the Gulf Stream and the Bay of Biscay.
DA - 2007/1//
PY - 2007/1//
DO - 10.1137/siread000049000003000419000001
VL - 49
IS - 3
SP - 419-420
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33847672254&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Problems and techniques: Introduction
AU - Ipsen, I.
T2 - SIAM Review
DA - 2007///
PY - 2007///
VL - 49
IS - 4
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-37249005235&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Problems and Techniques
AU - Ipsen, Ilse
T2 - SIAM Review
AB - In this issue, the Problems and Techniques section features papers concerned with parallel matrix vector multiplication, polynomial interpolation, and propagation of electromagnetic waves. The first paper, “Revisiting Hypergraph Models for Sparse Matrix Partitioning” by Bora Uçar and Cevdet Aykanat, is concerned with parallelizing matrix vector multiplication $y=Ax$, where the matrix A is sparse and rectangular. The authors propose a hypergraph model to describe dependences among the data and model communication among processors. In the hypergraph model, the elements of x and y and the rows of A are represented by vertices of a graph. If element $a_{i,j}$ of A is nonzero, then the multiplication $a_{ij}x_j$ contributes a nonzero summand and requires $x_j$ to be present in the processor holding row i. This dependence is accounted for with an undirected edge connecting $x_j$ with row i of A. A so-called net collects all dependences for a vertex: For instance, the net $n_x(j)$ contains vertex $x_j$ as well as all rows of A that have an edge with $x_j$. The problem of minimizing communication among processors can now be formulated as allocating the vertices to processors, so that each net has its vertices spread over as few processors as possible. The authors illustrate the effectiveness of hypergraph models when constraints are put on the allocation of the data to processors. When the German mathematician, physicist, and spectroscopist Carl David Tolmé Runge (1856–1927) interpolated the function $f(x)=1/(1+25x^2)$ at $n+1$ equally spaced points in the interval $[-1,1]$ by a polynomial of degree n, he made a startling observation: With increasing degree n, the polynomials approximate f less accurately—instead of, as one would have hoped, more accurately. Although the polynomials agree with f at the interpolation points, they oscillate between the interpolation points, and the oscillations worsen as the polynomial degree grows. Thence polynomial interpolation at equally spaced points fell into disrepute. It turns out, however, that interpolation at equally spaced points cannot be avoided altogether. It is necessary, for instance, in computational fluid dynamics, when one has to solve hyperbolic partial differential equations. Moreover, the interpolant may also have to retain the positivity, monotonicity, and boundedness of the underlying function. How to meet these demands in the face of Runge's phenomenon? This is the subject of Martin Berzins's paper “Adaptive Polynomial Interpolation on Evenly Spaced Meshes.” The third paper, “Uniform Asymptotics Applied to Ultrawideband Pulse Propagation” by Natalie Cartwright and Kurt Oughstun, deals with a problem that was first studied by the German theoretical physicist Arnold Sommerfeld (1868–1951) and his student, the French physicist Léon Brillouin (1889–1969): the propagation of electromagnetic waves in dispersive materials. The problem at hand is complicated by the fact that the pulse is an ultrawide band consisting of a wide range of frequencies. The propagation of the pulse is represented as a complex integral, and the authors derive a continuous asymptotic expansion of this integral by applying a combination of saddle point methods.
DA - 2007/1//
PY - 2007/1//
DO - 10.1137/siread000049000004000593000001
VL - 49
IS - 4
SP - 593-593
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-34548494833&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Model-Based Failure Detection on Nonlinear Systems: Theory and Transition
AU - Drake, Kimberly J.
AU - Campbell, Stephen L.
AU - Andjelkovic, Ivan
AU - Sweetingham, Kelly
T2 - Naval Engineers Journal
AB - Failure detection is an active area of Navy research due to its many important applications. Recently, an approach for multi-model identification and fault detection in the presence of bounded energy noise over finite time intervals has been introduced. This family of algorithms was originally designed to work on linear systems that can be modeled analytically. In this paper, efforts made toward extending this algorithm for fault detection to nonlinear systems along with efforts in testing this family of algorithms on real systems are discussed.
DA - 2007/10//
PY - 2007/10//
DO - 10.1111/j.0028-1425.2007.00022.x
VL - 119
IS - 2
SP - 93-107
LA - en
OP -
SN - 0028-1425 1559-3584
UR - http://dx.doi.org/10.1111/j.0028-1425.2007.00022.x
DB - Crossref
ER -
TY - JOUR
TI - The Hill–Robertson effect is a consequence of interplay between linkage, selection and drift: a commentary on ‘The effect of linkage on limits to artificial selection’ by W. G. Hill and A. Robertson
AU - Zeng, Zhao Bang
T2 - Genetics Research
AB - The Hill–Robertson effect is a consequence of interplay between linkage, selection and drift: a commentary on ‘The effect of linkage on limits to artificial selection’ by W. G. Hill and A. Robertson - Volume 89 Issue 5-6
DA - 2007/12//
PY - 2007/12//
DO - 10.1017/s0016672308009506
VL - 89
IS - 5-6
SP - 309-310
J2 - Genet. Res.
LA - en
OP -
SN - 0016-6723 1469-5073
UR - http://dx.doi.org/10.1017/s0016672308009506
DB - Crossref
ER -
TY - JOUR
TI - Immersed-interface finite-element methods for elliptic interface problems with nonhomogeneous jump conditions
AU - Gong, Y.
AU - Li, B.
AU - Li, Zhilin
T2 - SIAM Journal on Numerical Analysis
AB - In this work, a class of new finite-element methods, called immersed-interface finite-element methods, is developed to solve elliptic interface problems with nonhomogeneous jump conditions. Simple non-body-fitted meshes are used. A single function that satisfies the same nonhomogeneous jump conditions is constructed using a level-set representation of the interface. With such a function, the discontinuities across the interface in the solution and flux are removed, and an equivalent elliptic interface problem with homogeneous jump conditions is formulated. Special finite-element basis functions are constructed for nodal points near the interface to satisfy the homogeneous jump conditions. Error analysis and numerical tests are presented to demonstrate that such methods have an optimal convergence rate. These methods are designed as an efficient component of the finite-element level-set methodology for fast simulation of interface dynamics that does not require remeshing.
DA - 2007///
PY - 2007///
DO - 10.1137/060666482
VL - 46
IS - 1
SP - 472–495
KW - elliptic interface problems
KW - nonhomogeneous jump conditions
KW - immersed-interface finite-element method
KW - level-set functions
KW - error estimates
ER -
TY - JOUR
TI - Strategic analysis of speed and flexibility in sourcing textile products
AU - Hartman, Lisa M
DA - 2007///
PY - 2007///
ER -
TY - CONF
TI - AC 2007-3009: COMPUTER-BASED MODELING FOR ENGINEERS USING EXCEL AND VBA
AU - Roberts, Stephen
C2 - 2007///
C3 - 2007 ASEE
DA - 2007///
VL - 12
SP - 1
ER -
TY - CONF
TI - Computer-Based Modeling for Engineers using Excel and VBA
AU - Joines, J.A.
AU - Roberts, S.
AU - Raubenheimer, D.
C2 - 2007///
C3 - Proceedings of the ASEE International Conference
DA - 2007///
UR - http://www.asee.org/acPapers/code/getPaper.cfm?paperID=13338
ER -
TY - CONF
TI - A Comparison Meta-Heuristics for Large Scale Facility Location Problems with Economies of Scale
AU - Bucci, M.G.
AU - Kay, M.G.
AU - Warsing, D.P.
AU - Joines, J.A.
C2 - 2007///
C3 - Proceedings of the Industrial Engineering Research Conference
DA - 2007///
ER -
TY - JOUR
TI - AN EXPERIMENTAL STUDY ON SECURITY PROTOCOLS IN WLANS
AU - Agarwal, Avesh Kumar
AU - Wang, Wenye
T2 - WIRELESS NETWORK SECURITY
DA - 2007///
PY - 2007///
DO - 10.1007/978-0-387-33112-6_12
SP - 295-322
SN - 1860-4862
ER -
TY - CONF
TI - Formalizing communication protocols for multiagent systems
AU - Singh, M.P.
C2 - 2007///
C3 - IJCAI International Joint Conference on Artificial Intelligence
DA - 2007///
SP - 1519-1524
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-75649138061&partnerID=MN8TOARS
ER -
TY - CONF
TI - Formal trust model for multiagent systems
AU - Wang, Y.
AU - Singh, M.P.
C2 - 2007///
C3 - IJCAI International Joint Conference on Artificial Intelligence
DA - 2007///
SP - 1551-1556
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84880909594&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Fuzzy optimization and decision making (vol 4, pg 331, 2005)
AU - Wang, S.
AU - Fang, S. C.
AU - Nuttle, H. L. W.
T2 - Fuzzy Optimization and Decision Making
DA - 2007///
PY - 2007///
VL - 6
IS - 3
SP - 297-297
ER -
TY - JOUR
TI - Fuzzy optimization and decision making (vol 2, pg 41, 2003)
AU - Wang, S.
AU - Fang, S. C.
AU - Nuttle, H. L. W.
T2 - Fuzzy Optimization and Decision Making
DA - 2007///
PY - 2007///
VL - 6
IS - 3
SP - 297-297
ER -
TY - CONF
TI - Pricing and optimal resource allocation in next generation network services
AU - Kallitsis, M. G.
AU - Michailidis, G.
AU - Devetsikiotis, M.
C2 - 2007///
C3 - 2007 IEEE Sarnoff Symposium
DA - 2007///
SP - 457-461
ER -
TY - CONF
TI - Pricing and measurement-based optimal resource allocation in next generation network services
AU - Kallitsis, M. G.
AU - Michailidis, G.
AU - Devetsikiotis, M.
C2 - 2007///
C3 - 2007 IEEE Globecom Workshops, Proceedings
DA - 2007///
SP - 189-194
ER -
TY - JOUR
TI - Overlapping variance estimators for simulation
AU - Alexopoulos, Christos
AU - Argon, Nilay Tank
AU - Goldsman, David
AU - Tokol, Gamze
AU - Wilson, James R.
T2 - OPERATIONS RESEARCH
AB - To estimate the variance parameter (i.e., the sum of covariances at all lags) for a steady-state simulation output process, we formulate certain statistics that are computed from overlapping batches separately and then averaged over all such batches. We form overlapping versions of the area and Cramér–von Mises estimators using the method of standardized time series. For these estimators, we establish (i) their limiting distributions as the sample size increases while the ratio of the sample size to the batch size remains fixed; and (ii) their mean-square convergence to the variance parameter as both the batch size and the ratio of the sample size to the batch size increase. Compared with their counterparts computed from nonoverlapping batches, the estimators computed from overlapping batches asymptotically achieve reduced variance while maintaining the same bias as the sample size increases; moreover, the new variance estimators usually achieve similar improvements compared with the conventional variance estimators based on nonoverlapping or overlapping batch means. In follow-up work, we present several analytical and Monte Carlo examples, and we formulate efficient procedures for computing the overlapping estimators with only order-of-sample-size effort.
DA - 2007///
PY - 2007///
DO - 10.1287/opre.1070.0475
VL - 55
IS - 6
SP - 1090-1103
SN - 0030-364X
ER -
TY - JOUR
TI - Adaptive monitoring and accommodation of nonlinear actuator faults in positive real infinite dimensional systems
AU - Demetriou, Michael A.
AU - Ito, Kazufumi
AU - Smith, Ralph C.
T2 - IEEE TRANSACTIONS ON AUTOMATIC CONTROL
AB - We consider a class of positive real infinite dimensional systems which are subjected to incipient actuator faults. The actuator fault is modeled as a time varying transition from an initial (linear or even nonlinear) map into another unknown nonlinear map at the onset of the fault occurrence. An infinite dimensional adaptive detection observer is utilized to generate a residual signal in order to detect the fault occurrence and to assist in the fault accommodation. This is done via an automated control reconfiguration which utilizes information on the new actuator map and adjusts the controller via a right inverse of the new actuator map. A robust modification is utilized in order to avoid false alarms caused by unmodeled dynamics. An example is included to illustrate the applicability of the proposed detection scheme.
DA - 2007/12//
PY - 2007/12//
DO - 10.1109/TAC.2007.910694
VL - 52
IS - 12
SP - 2332-2338
SN - 1558-2523
KW - actuator faults
KW - distributed parameter systems
KW - fault accommodation
KW - nonlinear actuator dynamics
ER -
TY - JOUR
TI - A novel optimization approach for minimum cost design of trusses
AU - Kripakaran, Prakash
AU - Gupta, Abhinav
AU - Baugh, John W., Jr.
T2 - COMPUTERS & STRUCTURES
AB - This paper describes new optimization strategies that offer significant improvements in performance over existing methods for bridge-truss design. In this study, a real-world cost function that consists of costs on the weight of the truss and the number of products in the design is considered. We propose a new sizing approach that involves two algorithms applied in sequence – (1) a novel approach to generate a “good” initial solution and (2) a local search that attempts to generate the optimal solution by starting with the final solution from the previous algorithm. A clustering technique, which identifies members that are likely to have the same product type, is used with cost functions that consider a cost on the number of products. The proposed approach gives solutions that are much lower in cost compared to those generated in a comprehensive study of the same problem using genetic algorithms (GA). Also, the number of evaluations needed to arrive at the optimal solution is an order of magnitude lower than that needed in GAs. Since existing optimization techniques use cost functions like those of minimum-weight truss problems to illustrate their performance, the proposed approach is also applied to the same examples in order to compare its relative performance. The proposed approach is shown to generate solutions of not only better quality but also much more efficiently. To highlight the use of this sizing approach in a broader optimization framework, a simple geometry optimization algorithm that uses the sizing approach is presented. This algorithm is also shown to provide solutions better than the existing results in literature.
DA - 2007/12//
PY - 2007/12//
DO - 10.1016/j.compstruc.2007.04.006
VL - 85
IS - 23-24
SP - 1782-1794
SN - 1879-2243
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-36049020582&partnerID=MN8TOARS
KW - truss design
KW - structural optimization
KW - hybrid search
KW - genetic algorithms
KW - member grouping
KW - discrete sizing optimization
KW - cost minimization
ER -
TY - JOUR
TI - Wavelet-based neighborhood control for self-sizing networks
AU - Nalatwad, Srikant
AU - Devetslkiotis, Michael
T2 - SIMULATION-TRANSACTIONS OF THE SOCIETY FOR MODELING AND SIMULATION INTERNATIONAL
AB - The exponential growth of the Internet has turned it into a multiservice complex network of heterogeneous elements with dynamically changing traffic conditions. To regulate such a large scale network it is necessary to place intelligence in the nodes and find simple distributed rules and strategies that can produce meaningful and consistent behavior. These control mechanisms must be adaptive to effectively respond to continually changing network conditions. A “self-sizing” network can allocate link/switch capacity automatically and adaptively using online traffic data. Such adaptive, distributed, localized mechanisms are crucial to provide a scalable solution for controlling large, complex networks. In this paper, we propose a new, distributed self-sizing framework for locally controlled networks, which can support the stringent requirements of real-time applications in the Internet. Our unified and critical study of online resource allocation algorithms of two different classical approaches, led us to the use of adaptive multi-resolution decomposition (“wavelet”) algorithms. Our results show that by performing online resource allocation at each node based on their local knowledge, we can achieve considerable bandwidth savings and also satisfy QoS at the packet level. In our novel “neighborhood control” technique, we establish that by increasing the knowledge of some nodes so that higher self-sizing gains can be attained.
DA - 2007/3//
PY - 2007/3//
DO - 10.1177/0037549707081187
VL - 83
IS - 3
SP - 229-244
SN - 1741-3133
KW - self-sizing
KW - resource allocation
KW - wavelets
KW - neighborhood control
ER -
TY - JOUR
TI - The joint distribution of descent and major index over restricted sets of permutations
AU - Corteel, Sylvie
AU - Gessel, Ira M.
AU - Savage, Carla D.
AU - Wiif, Herbert S.
T2 - ANNALS OF COMBINATORICS
DA - 2007///
PY - 2007///
DO - 10.1007/s00026-007-0325-y
VL - 11
IS - 3-4
SP - 375-386
SN - 0219-3094
KW - permutation enumeration
KW - q-Eulerian polynomials
KW - P-partitions
ER -
TY - JOUR
TI - The Lumber Procurement and Kiln Scheduling Problem: A Hybrid-GA Approach
AU - Joines, J.A.
AU - Culbreth, C.T.
AU - Schultz, S.
T2 - Wood and Fiber Science
DA - 2007///
PY - 2007///
VL - 39
IS - 4
SP - 628-638
ER -
TY - JOUR
TI - Pagerank computation, with special attention to dangling nodes
AU - Ipsen, Ilse C. F.
AU - Selee, Teresa M.
T2 - SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS
AB - We present a simple algorithm for computing the PageRank (stationary distribution) of the stochastic Google matrix G. The algorithm lumps all dangling nodes into a single node. We express lumping as a similarity transformation of G and show that the PageRank of the nondangling nodes can be computed separately from that of the dangling nodes. The algorithm applies the power method only to the smaller lumped matrix, but the convergence rate is the same as that of the power method applied to the full matrix G. The efficiency of the algorithm increases as the number of dangling nodes increases. We also extend the expression for PageRank and the algorithm to more general Google matrices that have several different dangling node vectors, when it is required to distinguish among different classes of dangling nodes. We also analyze the effect of the dangling node vector on the PageRank and show that the PageRank of the dangling nodes depends strongly on that of the nondangling nodes but not vice versa. Last we present a Jordan decomposition of the Google matrix for the (theoretical) extreme case when all Web pages are dangling nodes.
DA - 2007///
PY - 2007///
DO - 10.1137/060664331
VL - 29
IS - 4
SP - 1281-1296
SN - 1095-7162
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-38049017083&partnerID=MN8TOARS
KW - stochastic matrix
KW - stationary distribution
KW - lumping
KW - rank-one matrix
KW - power method
KW - Jordan decomposition
KW - similarity transformation
KW - Google
ER -
TY - JOUR
TI - Optimal wavelength sharing policies in OBS networks subject to QoS constraints
AU - Yang, Li
AU - Rouskas, George N.
T2 - IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS
AB - We consider the general problem of optimizing the performance of OBS networks with multiple traffic classes subject to strict (absolute) QoS constraints in terms of the end-to-end burst loss rate of each guaranteed class of traffic. We employ Markov decision process (MDP) theory to obtain optimal wavelength sharing policies for two performance objectives, namely, maximization of weighted network throughput and minimization of the loss rate of best-effort traffic, while meeting the QoS guarantees. The randomized threshold policies we obtain are simple to implement and operate, and make effective use of statistical multiplexing. In particular, the threshold randomization feature enables the policies to allocate bandwidth at arbitrarily fine sub-wavelength granularity, hence making effective use of the available network capacity.
DA - 2007/12//
PY - 2007/12//
DO - 10.1109/JSAC-OCN.2007.029707
VL - 25
IS - 9
SP - 40-49
SN - 1558-0008
KW - optical burst switching (OBS) networks
KW - wavelength reservations
KW - quality of service
KW - Markov decision process
KW - randomized threshold policies
ER -
TY - JOUR
TI - Closure to "optimal design of redundant water distribution networks using a cluster of workstations" by Sujay V. Kumar, Troy A. Doby, John W. Baugh Jr., E. Downey Brill, and S. Ranji Ranjithan
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
DA - 2007///
PY - 2007///
DO - 10.1061/(asce)0733-9496(2007)133:6(580)
VL - 133
IS - 6
SP - 580-581
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-36349011269&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Robust receding horizon control for constrained linear fractional transformation parameter-dependent systems
AU - Wu, F.
AU - Chen, Y.
T2 - IET Control Theory and Applications
DA - 2007///
PY - 2007///
DO - 10.1049/ict-cta:20060305
VL - 1
IS - 5
SP - 1423-1430
ER -
TY - JOUR
TI - Integrating suppliers into new product development
AU - Handfield, Robert B.
AU - Lawson, Benn
T2 - RESEARCH-TECHNOLOGY MANAGEMENT
AB - OVERVIEW:New product development is becoming increasingly risky, expensive and reliant on disparate knowledge bases spread across multiple firms. Many organizations are devolving design responsibility to their suppliers in order to meet these challenges, yet may lack appropriate knowledge of “best practice” in managing supplier integration. For example, how to adjust their management practices to the timing of supplier integration and the degree of design responsibility award to suppliers. A survey of 134 global industrial organizations, and their efforts to integrate suppliers into their new product development processes, shows that early assessment of supplier capabilities and setting joint technology goals can improve the effectiveness of NPD project teams, and lead to improved product design and financial outcomes for the firm.
DA - 2007///
PY - 2007///
DO - 10.1080/08956308.2007.11657461
VL - 50
IS - 5
SP - 44-51
SN - 0895-6308
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-35348833556&partnerID=MN8TOARS
KW - new product development
KW - supplier integration
KW - supply management
ER -
TY - JOUR
TI - Efficient computation of overlapping variance estimators for simulation
AU - Alexopoulos, Christos
AU - Argon, Nilay Tanik
AU - Goldsman, David
AU - Steiger, Natalie M.
AU - Tokol, Gamze
AU - Wilson, James R.
T2 - INFORMS JOURNAL ON COMPUTING
AB - For a steady-state simulation output process, we formulate efficient algorithms to compute certain estimators of the process variance parameter (i.e., the sum of covariances at all lags), where the estimators are derived in principle from overlapping batches separately and then averaged over all such batches. The algorithms require order-of-sample-size work to evaluate overlapping versions of the area and Cramér–von Mises estimators arising in the method of standardized time series. Recently, Alexopoulos et al. showed that, compared with estimators based on nonoverlapping batches, the estimators based on overlapping batches achieve reduced variance while maintaining similar bias asymptotically as the batch size increases. We provide illustrative analytical and Monte Carlo results for M/M/1 queue waiting times and for a first-order autoregressive process. We also present evidence that the asymptotic distribution of each overlapping variance estimator can be closely approximated using an appropriately rescaled chi-squared random variable with matching mean and variance.
DA - 2007///
PY - 2007///
DO - 10.1287/ijoc.1060.0198
VL - 19
IS - 3
SP - 314-327
SN - 1526-5528
KW - steady-state simulation
KW - simulation output analysis methods
KW - method of batch means
KW - method of standardized time series
KW - area variance estimator
KW - Cramer-von Mises variance estimator
KW - nonoverlapping variance estimator
KW - overlapping variance estimator
ER -
TY - JOUR
TI - An evolution of virtual reality training designs for children with autism and fetal alcohol spectrum disorders
AU - Strickland, Dorothy C.
AU - McAllister, David
AU - Coles, Claire D.
AU - Osborne, Susan
T2 - TOPICS IN LANGUAGE DISORDERS
AB - This article describes an evolution of training programs to use first-person interaction in virtual reality (VR) situations to teach safety skills to children with autism spectrum disorder (ASD) and fetal alcohol spectrum disorder (FASD). Multiple VR programs for children aged 2 to 9 were built and tested between 1992 and 2007. Based on these results, a learning design evolved that uses practice in virtual space with guidance and correction by an animated character, strategic limitations on allowed actions to force correct patterning, and customization of worlds and responses to simplify user controls. This article describes program evolution by comparing design details and results as variations in behavioral responses between disorders, differences in skill set complexity between different safety skills being taught, and improved technology required changes in the virtual training methodology. A series of research projects are summarized in which the VR programs proved effective for teaching children with ASD and FASD new skills in the virtual space and, where measured, most children generalized the actions to the real world.
DA - 2007///
PY - 2007///
DO - 10.1097/01.TLD.0000285357.95426.72
VL - 27
IS - 3
SP - 226-241
SN - 1550-3259
ER -
TY - JOUR
TI - A very large scale neighborhood search algorithm for the q-mode problem
AU - Kulkarni, Girish
AU - Fathi, Yahya
T2 - IIE TRANSACTIONS
AB - The q-mode problem is a combinatorial optimization problem that arises in the context of partitioning a given collection of data vectors with categorical attributes. A neighborhood search algorithm is proposed for solving the q-mode problem. This algorithm is based on a very large scale neighborhood that is implicitly searched using network flow techniques. The algorithm is evaluated through a computational experiment using randomly generated instances. The results show that in general this algorithm obtains very-good-quality local optima, and that in instances with strong natural clusters the algorithm consistently finds optimal or near-optimal solutions.
DA - 2007/10//
PY - 2007/10//
DO - 10.1080/07408170701416657
VL - 39
IS - 10
SP - 971-984
SN - 0740-817X
KW - cluster analysis
KW - data mining
KW - local search/local improvement
ER -
TY - JOUR
TI - A dynamic TCP-Aware call admission control scheme. for generic next generation packet-switched wireless networks
AU - Wang, Xinbing
AU - Eun, Do Young
AU - Wang, Wenye
T2 - IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
AB - Traditional call admission control (CAC) schemes only consider call-level performance and are mainly designed for circuit-switched wireless network. Since future wireless communications will become packet-switched systems, the packet-level features could be explored to improve the system performance. This is especially true when the TCP-type of elastic applications are running over such packet-switched wireless networks, as the elasticity of TCP applications has more tolerance toward the throughput/delay variation than non-elastic traffic does. In order to efficiently utilize the system resource from an admission control perspective, we propose a TCP-aware CAC scheme to regulate the packet-level dynamics of TCP flows. We analyze the system performance under realistic scenarios in which (i) the call holding time for non-elastic traffic like voice is independent of system states and (ii) the call holding time for TCP type of traffic depends on the system state, i.e., on the TCP flow's transmission rate. Extensive simulations are presented under different scenarios to show that the proposed scheme can effectively improve the system performance in terms of call blocking probability, call-level throughput (call/min) and link utilization, in accordance with our theoretical results.
DA - 2007/9//
PY - 2007/9//
DO - 10.1109/TWC.2007.06064
VL - 6
IS - 9
SP - 3344-3352
SN - 1558-2248
KW - admission control
KW - wireless networks
KW - TCP
ER -
TY - JOUR
TI - The role of epistasis in the manifestation of heterosis: A systems-oriented approach
AU - Melchinger, A. E.
AU - Utz, H. F.
AU - Piepho, H. -P.
AU - Zeng, Z. -B.
AU - Schoen, C. C.
T2 - GENETICS
AB - Abstract Heterosis is widely used in breeding, but the genetic basis of this biological phenomenon has not been elucidated. We postulate that additive and dominance genetic effects as well as two-locus interactions estimated in classical QTL analyses are not sufficient for quantifying the contributions of QTL to heterosis. A general theoretical framework for determining the contributions of different types of genetic effects to heterosis was developed. Additive × additive epistatic interactions of individual loci with the entire genetic background were identified as a major component of midparent heterosis. On the basis of these findings we defined a new type of heterotic effect denoted as augmented dominance effect di* that comprises the dominance effect at each QTL minus half the sum of additive × additive interactions with all other QTL. We demonstrate that genotypic expectations of QTL effects obtained from analyses with the design III using testcrosses of recombinant inbred lines and composite-interval mapping precisely equal genotypic expectations of midparent heterosis, thus identifying genomic regions relevant for expression of heterosis. The theory for QTL mapping of multiple traits is extended to the simultaneous mapping of newly defined genetic effects to improve the power of QTL detection and distinguish between dominance and overdominance.
DA - 2007/11//
PY - 2007/11//
DO - 10.1534/genetics.107.077537
VL - 177
IS - 3
SP - 1815-1825
SN - 0016-6731
ER -
TY - JOUR
TI - A semiparametric approach for composite functional mapping of dynamic quantitative traits
AU - Yang, Runqing
AU - Gao, Huijiang
AU - Wang, Xin
AU - Zhang, Ji
AU - Zeng, Zhao-Bang
AU - Wu, Rongling
T2 - GENETICS
AB - Abstract Functional mapping has emerged as a powerful tool for mapping quantitative trait loci (QTL) that control developmental patterns of complex dynamic traits. Original functional mapping has been constructed within the context of simple interval mapping, without consideration of separate multiple linked QTL for a dynamic trait. In this article, we present a statistical framework for mapping QTL that affect dynamic traits by capitalizing on the strengths of functional mapping and composite interval mapping. Within this so-called composite functional-mapping framework, functional mapping models the time-dependent genetic effects of a QTL tested within a marker interval using a biologically meaningful parametric function, whereas composite interval mapping models the time-dependent genetic effects of the markers outside the test interval to control the genome background using a flexible nonparametric approach based on Legendre polynomials. Such a semiparametric framework was formulated by a maximum-likelihood model and implemented with the EM algorithm, allowing for the estimation and the test of the mathematical parameters that define the QTL effects and the regression coefficients of the Legendre polynomials that describe the marker effects. Simulation studies were performed to investigate the statistical behavior of composite functional mapping and compare its advantage in separating multiple linked QTL as compared to functional mapping. We used the new mapping approach to analyze a genetic mapping example in rice, leading to the identification of multiple QTL, some of which are linked on the same chromosome, that control the developmental trajectory of leaf age.
DA - 2007/11//
PY - 2007/11//
DO - 10.1534/genetics.107.077321
VL - 177
IS - 3
SP - 1859-1870
SN - 1943-2631
ER -
TY - JOUR
TI - Speed-mapping quantitative trait loci using microarrays
AU - Lai, Chao-Qiang
AU - Leips, Jeff
AU - Zou, Wei
AU - Roberts, Jessica F.
AU - Wollenberg, Kurt R.
AU - Parnell, Laurence D.
AU - Zeng, Zhao-Bang
AU - Ordovas, Jose M.
AU - Mackay, Trudy F. C.
T2 - NATURE METHODS
DA - 2007/10//
PY - 2007/10//
DO - 10.1038/NMETH1084
VL - 4
IS - 10
SP - 839-841
SN - 1548-7105
ER -
TY - JOUR
TI - Nonparametric Bayesian estimation of positive false discovery rates
AU - Tang, Yongqiang
AU - Ghosal, Subhashis
AU - Roy, Anindya
T2 - BIOMETRICS
AB - We propose a Dirichlet process mixture model (DPMM) for the P-value distribution in a multiple testing problem. The DPMM allows us to obtain posterior estimates of quantities such as the proportion of true null hypothesis and the probability of rejection of a single hypothesis. We describe a Markov chain Monte Carlo algorithm for computing the posterior and the posterior estimates. We propose an estimator of the positive false discovery rate based on these posterior estimates and investigate the performance of the proposed estimator via simulation. We also apply our methodology to analyze a leukemia data set.
DA - 2007/12//
PY - 2007/12//
DO - 10.1111/j.1541-0420.2007.00819.x
VL - 63
IS - 4
SP - 1126-1134
SN - 0006-341X
KW - Dirichlet mixture
KW - Dirichlet process
KW - Markov chain Monte Carlo
KW - multiple testing
KW - positive false discovery rate
KW - posterior estimates
ER -
TY - JOUR
TI - Complexity of path traffic grooming
AU - Iyer, Prashant
AU - Dutta, Rudra
AU - Savage, Carla D.
T2 - JOURNAL OF OPTICAL NETWORKING
AB - Feature Issue on Transmission in Optically Transparent Core NetworksThe problem of efficiently designing lightpaths and routing traffic on them in hybrid electro-optic data communication networks so that optical pass-through is maximized and the electronic switching cost is minimized is known as traffic grooming and has been studied extensively. Traffic grooming is known to be an inherently difficult problem. It has been shown to be NP-complete even for path networks, a simple topology in which lightpath wavelength assignment is tractable. In this paper, we explore the borderline between tractability and intractability by considering grooming in unidirectional path networks in which all traffic requests are destined for a single egress node. Whether the complete grooming problem is NP-hard with this restriction is an open question. We show that at least the problem of routing traffic on a given virtual topology to minimize electronic switching (NP-hard for path networks with arbitrary traffic matrices) becomes polynomial on the egress model. We also show that in the egress model, if the capacity constraint is relaxed, the entire problem becomes polynomial. If, in addition, traffic requests are uniform, we provide an explicit combinatorial formula for the optimum solution as well as an algorithm that constructs a routing that achieves this optimum. For the case of finite capacity and unit traffic requests, we show how to polynomially find a feasible solution that is optimal under reasonable assumptions.
DA - 2007/11/1/
PY - 2007/11/1/
DO - 10.1364/JON.6.001270
VL - 6
IS - 11
SP - 1270-1281
SN - 1536-5379
ER -
TY - JOUR
TI - Performance of a wavelet-based spectral procedure for steady-state simulation analysis
AU - Lada, E. K.
AU - Wilson, J. R.
AU - Steiger, N. M.
AU - Joines, J. A.
T2 - INFORMS Journal on Computing
AB - A summary and an analysis are given for an experimental performance evaluation of WASSP, an automated wavelet-based spectral method for constructing an approximate confidence interval on the steady-state mean of a simulation output process such that the delivered confidence interval satisfies user-specified requirements on absolute or relative precision as well as coverage probability. The experimentation involved three difficult test problems, each with an output process exhibiting some combination of the following characteristics: a long warm-up period, a persistent autocorrelation structure, or a highly nonnormal marginal distribution. These problems were used to compare the performance of WASSP with that of the Heidelberger-Welch algorithm and ASAP3, two sequential procedures based respectively on the methods of spectral analysis and nonoverlapping batch means. Concerning efficiency (required sample sizes) and robustness against the statistical anomalies commonly encountered in simulation studies, WASSP outperformed the Heidelberger-Welch procedure and compared favorably with ASAP3.
DA - 2007///
PY - 2007///
DO - 10.1287/ijoc.1050.0161
VL - 19
IS - 2
SP - 150–160
KW - simulation
KW - statistical analysis
KW - spectral analysis
KW - steady-state analysis
KW - wavelet analysis
ER -
TY - JOUR
TI - Nonlinear feedback controllers and compensators: a state-dependent Riccati equation approach
AU - Banks, H. T.
AU - Lewis, B. M.
AU - Tran, H. T.
T2 - COMPUTATIONAL OPTIMIZATION AND APPLICATIONS
AB - State-dependent Riccati equation (SDRE) techniques are rapidly emerging as general design and synthesis methods of nonlinear feedback controllers and estimators for a broad class of nonlinear regulator problems. In essence, the SDRE approach involves mimicking standard linear quadratic regulator (LQR) formulation for linear systems. In particular, the technique consists of using direct parameterization to bring the nonlinear system to a linear structure having state-dependent coefficient matrices. Theoretical advances have been made regarding the nonlinear regulator problem and the asymptotic stability properties of the system with full state feedback. However, there have not been any attempts at the theory regarding the asymptotic convergence of the estimator and the compensated system. This paper addresses these two issues as well as discussing numerical methods for approximating the solution to the SDRE. The Taylor series numerical methods works only for a certain class of systems, namely with constant control coefficient matrices, and only in small regions. The interpolation numerical method can be applied globally to a much larger class of systems. Examples will be provided to illustrate the effectiveness and potential of the SDRE technique for the design of nonlinear compensator-based feedback controllers.
DA - 2007/6//
PY - 2007/6//
DO - 10.1007/s10589-007-9015-2
VL - 37
IS - 2
SP - 177-218
SN - 1573-2894
KW - nonlinear feedback control
KW - nonlinear compensator
KW - state-dependent Riccati equations
ER -
TY - JOUR
TI - Efficiently querying large XML data repositories: A survey
AU - Gou, Gang
AU - Chirkova, Rada
T2 - IEEE TRANSACTIONS ON KNOWLEDGE AND DATA ENGINEERING
AB - Extensible markup language (XML) is emerging as a de facto standard for information exchange among various applications on the World Wide Web. There has been a growing need for developing high-performance techniques to query large XML data repositories efficiently. One important problem in XML query processing is twig pattern matching, that is, finding in an XML data tree D all matches that satisfy a specified twig (or path) query pattern Q. In this survey, we review, classify, and compare major techniques for twig pattern matching. Specifically, we consider two classes of major XML query processing techniques: the relational approach and the native approach. The relational approach directly utilizes existing relational database systems to store and query XML data, which enables the use of all important techniques that have been developed for relational databases, whereas in the native approach, specialized storage and query processing systems tailored for XML data are developed from scratch to further improve XML query performance. As implied by existing work, XML data querying and management are developing in the direction of integrating the relational approach with the native approach, which could result in higher query processing performance and also significantly reduce system reengineering costs.
DA - 2007/10//
PY - 2007/10//
DO - 10.1109/tkde.2007.1060
VL - 19
IS - 10
SP - 1381-1403
SN - 1041-4347
KW - XML query processing
KW - twig pattern matching
ER -
TY - JOUR
TI - Application of complex demodulation on bZIP and bHLH-PAS protein domains
AU - Wang, Z.
AU - Smith, C. E.
AU - Atchley, W. R.
T2 - Mathematical Biosciences
AB - Proteins are built with molecular modular building blocks such as an alpha-helix, beta-sheet, loop region and other structures. This is an economical way of constructing complex molecules. Periodicity analysis of protein sequences has allowed us to obtain meaningful information concerning their structure, function and evolution. In this work, complex demodulation (CDM) is introduced to detect functional regions in protein sequences data. More specifically, we analyzed bZIP and bHLH-PAS protein domains. Complex demodulation provided insightful information about changing amplitudes of periodic components in protein sequences. Furthermore, it was found that the local amplitude minimum or local amplitude maximum of the 3.6-aa periodic component is associated with protein structural or functional information due to the observation that the extrema are mainly located in the boundary area of two structural or functional regions.
DA - 2007///
PY - 2007///
DO - 10.1016/j.mbs.2007.01.004
VL - 207
IS - 2
SP - 204-218
ER -
TY - JOUR
TI - A roadmap for COMPREHENSIVE online privacy policy management
AU - Anton, Annie I.
AU - Bertino, Elisa
AU - Li, Ninghui
AU - Yu, Ting
T2 - COMMUNICATIONS OF THE ACM
AB - A framework supporting the privacy policy life cycle helps guide the kind of research to consider before sound privacy answers may be realized.
DA - 2007/7//
PY - 2007/7//
DO - 10.1145/1272516.1272522
VL - 50
IS - 7
SP - 109-116
SN - 1557-7317
ER -
TY - JOUR
TI - A periodic inventory model for stocking modular components
AU - Thomas, D.J.
AU - Warsing, Donald
T2 - Production and Operations Management
AB - We study the benefit obtained by exploiting modular product design in fulfilling exogenous demand for both a complete assembly and its components in a service parts inventory system. Our goal is to reduce overall service system costs by allowing assembly and/or disassembly (A/D) to occur at some unit cost per A/D action. In an extensive set of computational experiments, we compare a naive stocking and operating policy that treats all items independently and ignores the modular product structure and related A/D capability to the optimal base stock policy, and to a policy that allows A/D from the naive stocking levels. While extensive computational analysis shows that the optimal base stock policy improves the system cost between 3 to 26% over the naive approach, simply allowing A/D from the naive stocking levels captures a significant portion (an average of 67%) of the naive–optimal gap. Our computational results demonstrate that the optimization shifts the component-assembly mix from the naive levels and that limiting A/D capacity affects this mix. Limiting A/D capacity can actually increase the expected number of A/D actions (versus the uncapacitated case), since the optimization shifts stocking levels to reduce the probability that “too many” actions will be required.
DA - 2007///
PY - 2007///
DO - 10.1111/j.1937-5956.2007.tb00263.x
VL - 16
IS - 3
SP - 343-359
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-34547327241&partnerID=MN8TOARS
ER -
TY - JOUR
TI - View selection for real conjunctive queries
AU - Afrati, Foto
AU - Chirkova, Rada
AU - Gergatsoulis, Manolis
AU - Pavlaki, Vassia
T2 - ACTA INFORMATICA
DA - 2007/9//
PY - 2007/9//
DO - 10.1007/s00236-007-0046-z
VL - 44
IS - 5
SP - 289-321
SN - 1432-0525
ER -
TY - JOUR
TI - The relationships between supplier development, commitment, social capital accumulation and performance improvement
AU - Krause, Daniel R.
AU - Handfield, Robert B.
AU - Tyler, Beverly B.
T2 - JOURNAL OF OPERATIONS MANAGEMENT
AB - Abstract This study investigates the relationships between U.S. buying firms’ supplier development efforts, commitment, social capital accumulation with key suppliers, and buying firm performance. We identify linkages between supply chain management research on supplier development and organization theory research on social capital to consider how buying firm commitment to a long‐term relationship, cognitive capital (goals and values), structural capital (information sharing, supplier evaluation, supplier development), and relational capital (length of relationship, buyer dependency, supplier dependency) are related to buying firm performance improvements (cost improvements, and quality, delivery, flexibility improvements). Analysis of buying firms from the U.S. automotive and electronics industries provides support for the theory that buyer commitment and social capital accumulation with key suppliers can improve buying company performance. Moreover, the findings suggest that the relationships of structural and relational capital vary depending on the type of performance improvement considered.
DA - 2007/3//
PY - 2007/3//
DO - 10.1016/j.jom.2006.05.007
VL - 25
IS - 2
SP - 528-545
SN - 1873-1317
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33847682667&partnerID=MN8TOARS
KW - supply management
KW - purchasing
KW - supplier development
KW - social capital
KW - buyer-supplier relationship
ER -
TY - JOUR
TI - Real-time implementation of a frequency shaping controller on a cantilever beam
AU - Lewis, B. M.
AU - Tran, H. T.
T2 - APPLIED NUMERICAL MATHEMATICS
AB - In this paper, we present the real time implementation of a control methodology for the attenuation of beam vibrations in a smart structure paradigm caused by a narrow-band exogenous force. By narrow-band exogenous force we mean a periodic force over a narrow frequency band or a particular harmonic. The particular control method is based on the minimization of a frequency dependent quadratic cost functional. This control method has been used successfully in various applications; however, this investigation differs from other works in that it emphasizes the real-time implementation of this model-based control methodology using real-time partial state measurements.
DA - 2007///
PY - 2007///
DO - 10.1016/j.apnum.2006.07.017
VL - 57
IS - 5-7
SP - 778-790
SN - 0168-9274
ER -
TY - JOUR
TI - Preface of the special issue of APNUM - International Conference on Scientific Computing in Nanjing, China
AU - Li, Zhilin
AU - Song, Yongzhong
AU - Tang, Tao
T2 - APPLIED NUMERICAL MATHEMATICS
DA - 2007///
PY - 2007///
DO - 10.1016/j.apnum.2006.07.023
VL - 57
IS - 5-7
SP - 473-474
SN - 0168-9274
ER -
TY - JOUR
TI - Posterior convergence rates of dirichlet mixtures at smooth densities
AU - Ghosal, Subhashis
AU - Vaart, Aad
T2 - ANNALS OF STATISTICS
AB - We study the rates of convergence of the posterior distribution for Bayesian density estimation with Dirichlet mixtures of normal distributions as the prior. The true density is assumed to be twice continuously differentiable. The bandwidth is given a sequence of priors which is obtained by scaling a single prior by an appropriate order. In order to handle this problem, we derive a new general rate theorem by considering a countable covering of the parameter space whose prior probabilities satisfy a summability condition together with certain individual bounds on the Hellinger metric entropy. We apply this new general theorem on posterior convergence rates by computing bounds for Hellinger (bracketing) entropy numbers for the involved class of densities, the error in the approximation of a smooth density by normal mixtures and the concentration rate of the prior. The best obtainable rate of convergence of the posterior turns out to be equivalent to the well-known frequentist rate for integrated mean squared error n−2/5 up to a logarithmic factor.
DA - 2007/4//
PY - 2007/4//
DO - 10.1214/009053606000001271
VL - 35
IS - 2
SP - 697-723
SN - 0090-5364
KW - bracketing
KW - dirichlet mixture
KW - entropy
KW - maximum likelihood
KW - mixture of normals
KW - posterior distribution
KW - rate of convergence
KW - sieve
ER -
TY - JOUR
TI - Optimal control of obstacle problems by H-1-obstacles
AU - Ito, Kazufumi
AU - Kunisch, Karl
T2 - APPLIED MATHEMATICS AND OPTIMIZATION
DA - 2007///
PY - 2007///
DO - 10.1007/s00245-007-0877-6
VL - 56
IS - 1
SP - 1-17
SN - 1432-0606
KW - control of variational inequalities
KW - optimality system
KW - Moreau-Yosida approximation
ER -
TY - JOUR
TI - Enhanced features for design of traveling wave tubes using CHRISTINE-1D
AU - David, John A.
AU - Kory, Carol L.
AU - Tran, Hien T.
AU - Ives, R. Lawrence
AU - Chernin, David
T2 - IEEE TRANSACTIONS ON PLASMA SCIENCE
AB - Traveling wave tubes (TWTs) are vacuum devices invented in the early 1940s for amplification of radio frequency power. These devices are critical for radar, communications, and electronic warfare missions in the military, as well as in commercial applications. The physics-based design and simulation code CHRISTINE-1D was used in the past to explore different TWT circuit designs and to automate the process of parameter estimation. However, the current capability of CHRISTINE-1D allows optimization of only helix TWT designs and includes a limited number of optimization goal functions. In addition, the current optimizer in CHRISTINE-1D employs a modified steepest descent method to carry out the optimization process. The objectives of this paper are threefold: (1) to investigate optimization techniques that may be better suited for this problem (for example, simplex type methods such as Nelder-Mead and Dividing Rectangles); (2) to allow optimization of nonhelix TWTs; and (3) to implement new optimization goal functions. Finally, to show the feasibility of our approach, we apply our optimization algorithms to the problem of designing a folded waveguide slow-wave circuit.
DA - 2007/8//
PY - 2007/8//
DO - 10.1109/TPS.2007.902128
VL - 35
IS - 4
SP - 1056-1064
SN - 0093-3813
KW - DIviding RECTangles (DIRECT)
KW - folded waveguide slow-wave circuit
KW - goal functions
KW - Nelder-Mead
KW - optimization
KW - traveling wave tubes (TWTs)
ER -
TY - JOUR
TI - Direct transcription solution of optimal control problems with higher order state constraints: theory vs practice
AU - Betts, J. T.
AU - Campbell, S. L.
AU - Engelsone, A.
T2 - OPTIMIZATION AND ENGINEERING
DA - 2007/3//
PY - 2007/3//
DO - 10.1007/s11081-007-9000-8
VL - 8
IS - 1
SP - 1-19
SN - 1573-2924
KW - optimal control
KW - numerical methods
KW - direct transcription
KW - constraints
ER -
TY - JOUR
TI - Convergence rates of posterior distributions for noniid observations
AU - Ghosal, Subhashis
AU - Van Der Vaart, Aad
T2 - ANNALS OF STATISTICS
AB - We consider the asymptotic behavior of posterior distributions and Bayes estimators based on observations which are required to be neither independent nor identically distributed. We give general results on the rate of convergence of the posterior measure relative to distances derived from a testing criterion. We then specialize our results to independent, nonidentically distributed observations, Markov processes, stationary Gaussian time series and the white noise model. We apply our general results to several examples of infinite-dimensional statistical models including nonparametric regression with normal errors, binary regression, Poisson regression, an interval censoring model, Whittle estimation of the spectral density of a time series and a nonlinear autoregressive model.
DA - 2007/2//
PY - 2007/2//
DO - 10.1214/009053606000001172
VL - 35
IS - 1
SP - 192-223
SN - 0090-5364
KW - covering numbers
KW - Hellinger distance
KW - independent nonidentically distributed observations
KW - infinite dimensional model
KW - Markov chains
KW - posterior distribution
KW - rate of convergence
KW - tests
ER -
TY - JOUR
TI - A two-scale model for an array of AFM's cantilever in the static case
AU - Lenczner, M.
AU - Smith, R. C.
T2 - MATHEMATICAL AND COMPUTER MODELLING
AB - The primary objective of this paper is to present a simplified model for an array of Atomic Force Microscopes (AFMs) operating in static mode. Its derivation is based on the asymptotic theory of thin plates initiated by P. Ciarlet and P. Destuynder and on the two-scale convergence introduced by M. Lenczner which generalizes the theory of G. Nguetseng and G. Allaire. As an example, we investigate in full detail a particular configuration, which leads to a very simple model for the array. Aspects of the theory for this configuration are illustrated through simulation results. Finally the formulation of our theory of two-scale convergence is fully revisited. All the proofs are reformulated in a significantly simpler manner.
DA - 2007/9//
PY - 2007/9//
DO - 10.1016/j.mcm.2006.12.028
VL - 46
IS - 5-6
SP - 776-805
SN - 1872-9479
KW - atomic force microscopy
KW - microsystems arrays
KW - multiscale modeling
KW - homogenization
ER -
TY - JOUR
TI - A study of numerical methods for the level set approach
AU - Gremaud, Pierre A.
AU - Kuster, Christopher M.
AU - Li, Zhilin
T2 - APPLIED NUMERICAL MATHEMATICS
AB - The computation of moving curves by the level set method typically requires reinitializations of the underlying level set function. Two types of reinitialization methods are studied: a high order “PDE” approach and a second order Fast Marching method. Issues related to the efficiency and implementation of both types of methods are discussed, with emphasis on the tube/narrow band implementation and accuracy considerations. The methods are also tested and compared. Fast Marching reinitialization schemes are faster but limited to second order, PDE based reinitialization schemes can easily be made more accurate but are slower, even with a tube/narrow band implementation.
DA - 2007///
PY - 2007///
DO - 10.1016/j.apnum.2006.07.022
VL - 57
IS - 5-7
SP - 837-846
SN - 0168-9274
ER -
TY - JOUR
TI - A reduced Hsieh-Clough-Tocher element with splitting based on an arbitrary interior point
AU - Peker, A. S.
AU - Lavery, J. E.
AU - Fang, S.-C.
T2 - JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS
AB - We present formulas for a reduced Hsieh–Clough–Tocher (rHCT) element with splitting based on an arbitrary interior point. These formulas use local barycentric coordinates in each of the subtriangles and are not significantly more complicated than formulas for an rHCT element with splitting based on the centroid.
DA - 2007/9/1/
PY - 2007/9/1/
DO - 10.1016/j.jmaa.2006.12.030
VL - 333
IS - 1
SP - 500-504
SN - 0022-247X
KW - Bernstein-Bezier
KW - Clough-Tocher element
KW - reduced Hsieh-Clough-Tocher element
KW - splitting
KW - subtriangle
KW - triangle
ER -
TY - JOUR
TI - A fast iterative solver for scattering by elastic objects in layered media
AU - Ito, K.
AU - Toivanen, J.
T2 - APPLIED NUMERICAL MATHEMATICS
AB - We developed a fast iterative solver for computing time-harmonic acoustic waves scattered by an elastic object in layered media. The discretization of the problem was performed using a finite element method with linear elements based on a locally body-fitted uniform triangulation. We used a domain decomposition preconditioner in the iterative solution of the resulting system of linear equations. The preconditioner was based on a cyclic reduction type fast direct solver. The solution procedure reduces GMRES iterates onto a sparse subspace which decreases the storage and computational requirements essentially. The numerical results demonstrate the effectiveness of the proposed approach for two-dimensional domains that are hundreds of wavelengths wide and require the solution of linear systems with several millions of unknowns.
DA - 2007///
PY - 2007///
DO - 10.1016/j.apnum.2006.07.020
VL - 57
IS - 5-7
SP - 811-820
SN - 1873-5460
ER -
TY - JOUR
TI - A consistent nonparametric Bayesian procedure for estimating autoregressive conditional densities
AU - Tang, Yongqiang
AU - Ghosal, Subhashis
T2 - COMPUTATIONAL STATISTICS & DATA ANALYSIS
AB - This article proposes a Bayesian infinite mixture model for the estimation of the conditional density of an ergodic time series. A nonparametric prior on the conditional density is described through the Dirichlet process. In the mixture model, a kernel is used leading to a dynamic nonlinear autoregressive model. This model can approximate any linear autoregressive model arbitrarily closely while imposing no constraint on parameters to ensure stationarity. We establish sufficient conditions for posterior consistency in two different topologies. The proposed method is compared with the mixture of autoregressive model [Wong and Li, 2000. On a mixture autoregressive model. J. Roy. Statist. Soc. Ser. B 62(1), 91–115] and the double-kernel local linear approach [Fan et al., 1996. Estimation of conditional densities and sensitivity measures in nonlinear dynamical systems. Biometrika 83, 189–206] by simulations and real examples. Our method shows excellent performances in these studies.
DA - 2007/5/15/
PY - 2007/5/15/
DO - 10.1016/j.csda.2006.06.020
VL - 51
IS - 9
SP - 4424-4437
SN - 1872-7352
KW - Dirichlet process mixture models
KW - posterior consistency
KW - no-gaps algorithm
ER -
TY - JOUR
TI - The additional dynamics of least squares completions for linear differential algebraic equations
AU - Okay, Irfan
AU - Campbell, Stephen L.
AU - Kunkel, Peter
T2 - LINEAR ALGEBRA AND ITS APPLICATIONS
AB - Several approaches have been proposed for numerically solving lower dimensional, nonlinear, higher index differential algebraic equations (DAEs) for which more classical numerical methods such as backward differentiation or implicit Runge–Kutta may not be appropriate. One of these approaches is called explicit integration (EI). This approach is based on solving nonlinear DAE derivative arrays using nonlinear singular least squares methods. This results in a computed ODE, called the least squares completion, whose solutions contain those of the original DAE. This ODE is then integrated by a classical numerical method. The additional dynamics of the least squares completion can affect the numerical solution of the DAE. This paper begins the study of determining these extra dynamics.
DA - 2007/9/1/
PY - 2007/9/1/
DO - 10.1016/j.laa.2007.02.005
VL - 425
IS - 2-3
SP - 471-485
SN - 1873-1856
KW - differential algebraic equations
KW - DAEs
KW - extra dynamics
ER -
TY - JOUR
TI - Performance analysis of an ingress switch in a JumpStart optical burst switching network
AU - Xu, Lisong
AU - Perros, Harry G.
T2 - PERFORMANCE EVALUATION
AB - We consider an ingress optical burst switching (OBS) node employing the JumpStart signaling protocol. The switch serves a number of users, each connected to the switch with a fiber link that supports multiple wavelengths. Each wavelength is associated with a 3-state Markovian burst arrival process which permits short and long bursts to be modeled. We model the ingress switch as a closed multi-class non-product-form queueing network, which we analyze approximately by decomposition. Specifically, we develop new techniques to analyze the queueing network, first assuming a single class of customers, and subsequently multiple classes of customers. These analytical techniques have applications to general queueing networks beyond the one studied in this paper. We also develop computationally efficient approximate algorithms to analyze an ingress switch in the limiting case where the number of wavelengths is large. The algorithms have a good accuracy, and they provide insight into the effect of various system parameters on the performance of an ingress OBS switch.
DA - 2007/5//
PY - 2007/5//
DO - 10.1016/j.peva.2006.05.012
VL - 64
IS - 4
SP - 315-346
SN - 1872-745X
KW - optical burst switching
KW - JumpStart project
KW - Marie's algorithm
KW - multi-class queueing networks
KW - closed non-product-form queueing networks
ER -
TY - JOUR
TI - Generalized wavelength sharing policies for absolute QoS guarantees in OBS networks
AU - Yang, Li
AU - Rouskas, George N.
T2 - IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS
AB - We consider the problem of supporting absolute QoS guarantees in terms of the end-to-end burst loss in OBS networks. We present a parameterized model for wavelength sharing which provides for isolation among different traffic classes while also making efficient use of wavelength capacity through statistical multiplexing. We develop a heuristic to optimize the policy parameters for a single link of an OBS network. We also develop a methodology for translating the end-to-end QoS requirements into appropriate per-link parameters so as to provide network-wide guarantees. Our approach is easy to implement, it can support a wide variety of traffic classes, and is effective in meeting the QoS requirements and keeping the loss rate of best-effort and overall traffic low
DA - 2007/4//
PY - 2007/4//
DO - 10.1109/TWC.2007.026706
VL - 25
IS - 4
SP - 93-104
SN - 1558-0008
KW - optical burst switching
KW - wavelength division multiplexing
KW - resource sharing policies
KW - quality of service
ER -
TY - JOUR
TI - An augmented approach for Stokes equations with a discontinuous viscosity and singular forces
AU - Li, Zhilin
AU - Ito, Kazufumi
AU - Lai, Ming-Chih
T2 - COMPUTERS & FLUIDS
AB - For Stokes equations with a discontinuous viscosity across an arbitrary interface or/and singular forces along the interface, it is known that the pressure is discontinuous and the velocity is non-smooth. It has been shown that these discontinuities are coupled together, which makes it difficult to obtain accurate numerical solutions. In this paper, a new numerical method that decouples the jump conditions of the fluid variables through two augmented variables has been developed. The GMRES iterative method is used to solve the Schur complement system for the augmented variables that are only defined on the interface. The augmented approach also rescales the Stokes equations in such a way that a fast Poisson solver can be used in each iteration. Numerical tests using examples that have analytic solutions show that the new method has average second order accuracy for the velocity in the infinity norm. An example of a moving interface problem is also presented.
DA - 2007/3//
PY - 2007/3//
DO - 10.1016/j.compfluid.2006.03.003
VL - 36
IS - 3
SP - 622-635
SN - 1879-0747
ER -
TY - JOUR
TI - A stress-dependent hysteresis model for ferroelectric materials
AU - Ball, Brian L.
AU - Smith, Ralph C.
AU - Kim, Sang-Joo
AU - Seelecke, Stefan
T2 - JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES
AB - This article addresses the development of a homogenized energy model which characterizes the ferroelastic switching mechanisms inherent to ferroelectric materials in a manner suitable for subsequent transducer and control design. In the first step of the development, we construct Helmholtz and Gibbs energy relations which quantify the potential and electrostatic energy associated with 90 and 180 dipole orientations. Equilibrium relations appropriate for homogeneous materials in the absence or presence of thermal relaxation are respectively determined by minimizing the Gibbs energy or balancing the Gibbs and relative thermal energies using Boltzmann principles. In the final step of the development, stochastic homogenization techniques are employed to construct macroscopic models suitable for nonhomogeneous, polycrystalline compounds. Attributes and limitations of the characterization framework are illustrated through comparison with experimental PLZT data.
DA - 2007/1//
PY - 2007/1//
DO - 10.1177/1045389X07070937
VL - 18
IS - 1
SP - 69-88
SN - 1530-8138
KW - PZT
KW - PLZT
KW - ferroelastic
KW - THUNDER
KW - hysteresis
KW - ferroelectric
KW - Helmholtz
ER -
TY - JOUR
TI - Solving variational inequalities defined on a domain with infinitely many linear constraints
AU - Fang, Shu-Cherng
AU - Wu, Soonyi
AU - Birbil, S. Ilker
T2 - COMPUTATIONAL OPTIMIZATION AND APPLICATIONS
AB - We study a variational inequality problem whose domain is defined by infinitely many linear inequalities. A discretization method and an analytic center based inexact cutting plane method are proposed. Under proper assumptions, the convergence results for both methods are given. We also provide numerical examples to illustrate the proposed methods.
DA - 2007/5//
PY - 2007/5//
DO - 10.1007/s10589-007-9013-4
VL - 37
IS - 1
SP - 67-81
SN - 1573-2894
KW - variational inequality problem
KW - analytic center based cutting plane method
KW - discretization method
KW - semi-infinite programming
ER -
TY - JOUR
TI - Simulation of fusion plasmas: Current status and future direction
AU - Batchelor, D. A.
AU - Beck, M.
AU - Becoulet, A.
AU - Budny, R. V.
AU - Chang, C. S.
AU - Diamond, P. H.
AU - Dong, J. Q.
AU - Fu, G. Y.
AU - Fukuyama, A.
AU - Hahm, T. S.
AU - Keyes, D. E.
AU - Kishimoto, Y.
AU - Klasky, S.
AU - Lao, L. L.
AU - Li, K.
AU - Lin, Z.
AU - Ludaescher, B.
AU - Manickam, J.
AU - Nakajima, N.
AU - a,
T2 - Plasma Science & Technology
DA - 2007///
PY - 2007///
VL - 9
IS - 3
SP - 312-387
ER -
TY - JOUR
TI - Queuing analysis of power management in the IEEE 802.11 based wireless LANs
AU - Lei, H. Y.
AU - Nilsson, A. A.
T2 - IEEE Transactions on Wireless Communications
DA - 2007///
PY - 2007///
DO - 10.1109/TWC.2007.04783
VL - 6
IS - 4
SP - 1286-1294
ER -
TY - JOUR
TI - Posterior consistency of Dirichlet mixtures for estimating a transition density
AU - Tang, Yongqiang
AU - Ghosal, Subhashis
T2 - JOURNAL OF STATISTICAL PLANNING AND INFERENCE
AB - The Dirichlet process mixture of normal densities has been successfully used as a prior for Bayesian density estimation for independent and identically distributed (i.i.d.) observations. A Markov model, which generalizes the i.i.d. set up, may be thought of as a suitable framework for observations arising over time. The predictive density of the future observation is then given by the posterior expectation of the transition density given the observations. We consider a Dirichlet process mixture prior for the transition density and study posterior consistency. Like the i.i.d. case, posterior consistency is obtained if the Kullback–Leibler neighborhoods of the true transition density receive positive prior probabilities and uniformly exponentially consistent tests exist for testing the true density against the complement of its neighborhoods. We show that under reasonable conditions, the Kullback–Leibler property holds for the Dirichlet mixture prior. For certain topologies on the space of transition densities, we show consistency holds under appropriate conditions by constructing the required tests. This approach, however, may not always lead to the best possible results. By modifying a recent approach of Walker [2004. New approaches to Bayesian consistency. Ann. Statist. 32, 2028–2043] for the i.i.d. case, we also show that better conditions for consistency can be given for certain weaker topologies.
DA - 2007/6/1/
PY - 2007/6/1/
DO - 10.1016/j.jspi.2006.03.007
VL - 137
IS - 6
SP - 1711-1726
SN - 0378-3758
KW - Dirichlet mixture
KW - Markov process
KW - posterior consistency
KW - transition density
KW - uniformly exponentially consistent tests
ER -
TY - JOUR
TI - Optimal bilinear control of an abstract Schrodinger equation
AU - Ito, Kazufumi
AU - Kunisch, Karl
T2 - SIAM JOURNAL ON CONTROL AND OPTIMIZATION
AB - Well‐posedness of abstract quantum mechanical systems is considered and the existence of optimal control of such systems is proved. First order optimality systems are derived. Convergence of the monotone scheme for the solution of the optimality system is proved.
DA - 2007///
PY - 2007///
DO - 10.1137/05064254X
VL - 46
IS - 1
SP - 274-287
SN - 0363-0129
KW - Schrodinger equation
KW - C(0)-groups
KW - optimal control
KW - optimality systems
KW - monotone scheme
ER -
TY - JOUR
TI - Linear combinations of overlapping variance estimators for simulation
AU - Aktaran-Kalayci, Tuba
AU - Goldsman, David
AU - Wilson, James R.
T2 - OPERATIONS RESEARCH LETTERS
AB - We estimate the variance parameter of a stationary simulation-generated process using a linear combination of overlapping standardized time series (STS) area variance estimators based on different batch sizes. We establish the linear-combination estimator's asymptotic distribution, presenting analytical and simulation-based results exemplifying its potential for improvements in accuracy and computational efficiency.
DA - 2007/7//
PY - 2007/7//
DO - 10.1016/j.orl.2006.08.007
VL - 35
IS - 4
SP - 439-447
SN - 1872-7468
KW - simulation
KW - stationary process
KW - variance estimation
KW - standardized time series
KW - area estimator
KW - overlapping area estimator
ER -
TY - JOUR
TI - Following the thread: Industry cluster theory, the New England cotton textiles industry, and implications for future supply chain research
AU - Bozarth, Cecil
AU - Blackhurst, Jennifer
AU - Handfield, Robert B.
T2 - PRODUCTION AND OPERATIONS MANAGEMENT
AB - The purpose of this paper is to introduce supply chain management researchers to industry cluster theory within the context of supply chain management decisions. Industry cluster theory emphasizes the explicit and implicit benefits that accrue to various economic players due to geographic proximity. As such, it provides a contrasting view to the current pressure on supply chains to seek out the “best” partners, regardless of location. We review the theory behind industry clusters, and illustrate it using the example of the New England cotton textile industry. Incorporating these concepts into future research has the potential to improve our understanding of how decisions regarding supply chain location and sourcing decisions are currently made, and what role location-based benefits should play in these decisions.
DA - 2007///
PY - 2007///
DO - 10.1111/j.1937-5956.2007.tb00172.x
VL - 16
IS - 1
SP - 154-157
SN - 1937-5956
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-34249710741&partnerID=MN8TOARS
KW - industry cluster theory
KW - supply chain management
KW - textile industry
ER -
TY - JOUR
TI - Direct transcription solution of high index optimal control problems and regular Euler-Lagrange equations
AU - Campbell, Stephen L.
AU - Maerz, Roswitha
T2 - JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS
AB - Direct transcription methods are used to solve optimal control problems in many industrial settings. Models for physical systems often take the form of differential algebraic equations (DAEs). The index of the DAE traditionally is viewed as an important factor in deciding whether a particular numerical approach should be used. Recently it has been observed that what the user thinks is the index of the DAE may not be the same as the index available to the optimization software. An investigation of this fact is underway in order to develop guidelines to assist users of various numerical optimal control packages. This paper develops some theoretical results that will be needed for this development.
DA - 2007/5/15/
PY - 2007/5/15/
DO - 10.1016/j.cam.2006.02.024
VL - 202
IS - 2
SP - 186-202
SN - 1879-1778
KW - direct transcription
KW - optimal control
KW - control selection
KW - numerical algorithms
KW - differential algebraic equations
ER -
TY - JOUR
TI - Cost-effective single-hub WDM ring networks: A proposal and analysis
AU - Bouabdallah, N.
AU - Perros, H.
T2 - Computer Networks (Amsterdam, Netherlands : 1999)
AB - In this paper, we study a new concept of traffic grooming in wavelength-division multiplexing (WDM) ring networks that aims at eliminating both the bandwidth underutilization and the scalability concerns that are typical of all-optical wavelength routed ring networks. Our objective is to reduce the network cost while preserving the benefits of all-optical WDM ring networks. In order to assess the efficiency of our proposal, all underlying network costs are compared. These costs include that of the transceivers required at node level, as well as the number of wavelengths. Our results show that the proposed aggregation technique can significantly improve the resource utilization while reducing the network cost.
DA - 2007///
PY - 2007///
DO - 10.1016/j.comnet.2007.04.014
VL - 51
IS - 13
SP - 3878-3901
ER -
TY - JOUR
TI - Convergence of the primal-dual active set strategy for diagonally dominant systems
AU - Ito, Kazufumi
AU - Kunisch, Karl
T2 - SIAM JOURNAL ON CONTROL AND OPTIMIZATION
AB - Sufficient conditions for global convergence of the primal-dual active set strategy for finite and infinite dimensional quadratic, as well as nonlinear optimization, problems with affine equality and inequality constraints are presented. These conditions involve diagonal dominance and cone preserving properties of the operator defining the cost functional. Globalization strategies are also provided, and specific sufficient conditions for the primal-dual active set step to have a descent property are given.
DA - 2007///
PY - 2007///
DO - 10.1137/050632713
VL - 46
IS - 1
SP - 14-34
SN - 0363-0129
KW - primal-dual active set strategy
KW - diagonally dominant systems
KW - bilateral constraints
KW - globalization
ER -
TY - JOUR
TI - The severity of supply chain disruptions: Design characteristics and mitigation capabilities
AU - Craighead, Christopher W.
AU - Blackhurst, Jennifer
AU - Rungtusanatham, M. Johnny
AU - Handfield, Robert B.
T2 - DECISION SCIENCES
AB - ABSTRACT Supply chain disruptions and the associated operational and financial risks represent the most pressing concern facing firms that compete in today's global marketplace. Extant research has not only confirmed the costly nature of supply chain disruptions but has also contributed relevant insights on such related issues as supply chain risks, vulnerability, resilience, and continuity. In this conceptual note, we focus on a relatively unexplored issue, asking and answering the question of how and why one supply chain disruption would be more severe than another. In doing so, we argue, de facto, that supply chain disruptions are unavoidable and, as a consequence, that all supply chains are inherently risky. Employing a multiple‐method, multiple‐source empirical research design, we derive novel insights, presented as six propositions that relate the severity of supply chain disruptions (i) to the three supply chain design characteristics of density, complexity, and node criticality and (ii) to the two supply chain mitigation capabilities of recovery and warning. These findings not only augment existing knowledge related to supply chain risk, vulnerability, resilience, and business continuity planning but also call into question the wisdom of pursuing such practices as supply base reduction, global sourcing, and sourcing from supply clusters.
DA - 2007/2//
PY - 2007/2//
DO - 10.1111/j.1540-5915.2007.00151.x
VL - 38
IS - 1
SP - 131-156
SN - 1540-5915
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-34047184222&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Output feedback stabilization of linear systems with actuator saturation
AU - Wu, Fen
AU - Lin, Zongli
AU - Zheng, Qian
T2 - IEEE TRANSACTIONS ON AUTOMATIC CONTROL
AB - The note presents a method for designing an output feedback law that stabilizes a linear system subject to actuator saturation with a large domain of attraction. This method applies to general linear systems including strictly unstable ones. A nonlinear output feedback controller is first expressed in the form of a quasi-LPV system. Conditions under which the closed-loop system is locally asymptotically stable are then established in terms of the coefficient matrices of the controller. The design of the controller (coefficient matrices) that maximizes an estimate of the domain of attraction is then formulated and solved as an optimization problem with LMI constraints
DA - 2007/1//
PY - 2007/1//
DO - 10.1109/TAC.2006.886498
VL - 52
IS - 1
SP - 122-128
SN - 1558-2523
KW - actuator saturation
KW - domain of attraction
KW - invariant set
KW - output feedback
KW - stability
ER -
TY - JOUR
TI - On Roth's pseudo equivalence over rings
AU - Hartwig, R. E.
AU - Patricio, P.
T2 - Electronic Journal of Linear Algebra
AB - The pseudo-equivalence of a block lower triangular matrix T = [Tij ] over a regular ring and its block diagonal matrix D(T)=[Tii] is characterized in terms of suitable Roth consistency conditions. The latter can in turn be expressed in terms of the solvability of certain matrix equations of the form TiiX − Y Tjj = Uij .
DA - 2007///
PY - 2007///
DO - 10.13001/1081-3810.1187
VL - 16
SP - 111-124
ER -
TY - JOUR
TI - Integer programming models for the q-mode problem
AU - Kulkarni, Girish
AU - Fathi, Yahya
T2 - EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
AB - The q-mode problem is a combinatorial optimization problem that requires partitioning of objects into clusters. We discuss theoretical properties of an existing mixed integer programming (MIP) model for this problem and offer alternative models and enhancements. Through a comprehensive experiment we investigate computational properties of these MIP models. This experiment reveals that, in practice, the MIP approach is more effective for instances containing strong natural clusters and it is not as effective for instances containing weak natural clusters. The experiment also reveals that one of the MIP models that we propose is more effective than the other models for solving larger instances of the problem.
DA - 2007/10/16/
PY - 2007/10/16/
DO - 10.1016/j.ejor.2006.08.039
VL - 182
IS - 2
SP - 612-625
SN - 1872-6860
KW - integer programming
KW - linear programming
KW - cluster analysis
KW - data mining
ER -
TY - JOUR
TI - Editor's introduction: Special issue honoring Perwez Shahabuddin
AU - Wilson, James R.
T2 - ACM TRANSACTIONS ON MODELING AND COMPUTER SIMULATION
DA - 2007/4//
PY - 2007/4//
DO - 10.1145/1225275.1225276
VL - 17
IS - 2
SP -
SN - 1049-3301
ER -
TY - JOUR
TI - A tabu search algorithm for maximum parsimony phylogeny inference
AU - Lin, Yu-Min
AU - Fang, Shu-Cherng
AU - Thorne, Jeffrey L.
T2 - EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
AB - Phylogeny reconstruction is too complex a combinatorial problem for an exhaustive search, because the number of possible solutions increases exponentially with the number of taxa involved. In this paper, we adopt the parsimony principle and design a tabu search algorithm for finding a most parsimonious phylogeny tree. A special array structure is employed to represent the topology of trees and to generate the neighboring trees. We test the proposed tabu search algorithm on randomly selected data sets obtained from nuclear ribosomal DNA sequence data. The experiments show that our algorithm explores fewer trees to reach the optimal one than the commonly used program “dnapenny” (branch-and-bound based) while it generates much more accurate results than the default options of the program “dnapars” (heuristic search based). The percentage of search space needed to find the best solution for our algorithm decreased rapidly as the number of taxa increased. For a 20-taxon phylogeny problem, it needs on average to examine only 3.92 × 10−15% of the sample space.
DA - 2007/2/1/
PY - 2007/2/1/
DO - 10.1016/j.ejor.2005.10.031
VL - 176
IS - 3
SP - 1908-1917
SN - 1872-6860
KW - tabu search
KW - OR in biology
KW - bioinformatics
KW - phylogeny inference
KW - maximum parsimony
ER -
TY - JOUR
TI - The directional p-median problem: Definition, complexity, and algorithms
AU - Jackson, Laura E.
AU - Rouskas, George N.
AU - Stallmann, Matthias F. M.
T2 - EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
AB - An instance of a p-median problem gives n demand points. The objective is to locate p supply points in order to minimize the total distance of the demand points to their nearest supply point. p-Median is polynomially solvable in one dimension but NP-hard in two or more dimensions, when either the Euclidean or the rectilinear distance measure is used. In this paper, we treat the p-median problem under a new distance measure, the directional rectilinear distance, which requires the assigned supply point for a given demand point to lie above and to the right of it. In a previous work, we showed that the directional p-median problem is polynomially solvable in one dimension; we give here an improved solution through reformulating the problem as a special case of the constrained shortest path problem. We have previously proven that the problem is NP-complete in two or more dimensions; we present here an efficient heuristic to solve it. Compared to the robust Teitz and Bart heuristic, our heuristic enjoys substantial speedup while sacrificing little in terms of solution quality, making it an ideal choice for real-world applications with thousands of demand points.
DA - 2007/6/16/
PY - 2007/6/16/
DO - 10.1016/j.ejor.2005.06.080
VL - 179
IS - 3
SP - 1097-1108
SN - 0377-2217
KW - directional p-median problem
KW - traffic quantization
KW - vector quantization
ER -
TY - JOUR
TI - Satisfying due-dates in the presence of sequence dependent family setups with a special comedown structure
AU - Taner, Mehmet R.
AU - Hodgson, Thom J.
AU - King, Russell E.
AU - Schultz, Scott R.
T2 - COMPUTERS & INDUSTRIAL ENGINEERING
AB - This paper addresses a static, n-job, single-machine scheduling problem with sequence dependent family setups. The setup matrix follows a special structure where a constant setup is required only if a job from a smaller indexed family is an immediate successor of one from a larger indexed family. The objective is to minimize the maximum lateness (Lmax). A two-step neighborhood search procedure and an implicit enumeration scheme are proposed. Both procedures exploit the problem structure. The enumeration scheme produces optimum solutions to small and medium sized problems in reasonable computational times, yet it fails to perform efficiently in larger instances. Computational results show that the heuristic procedure is highly effective, and is efficient even for extremely large problems.
DA - 2007/2//
PY - 2007/2//
DO - 10.1016/j.cie.2006.10.008
VL - 52
IS - 1
SP - 57-70
SN - 0360-8352
KW - scheduling
KW - maximum lateness
KW - sequence dependent family setups
KW - comedown
KW - heuristics
ER -
TY - JOUR
TI - Robust and gain-scheduling control of LFT systems through duality and conjugate Lyapunov functions
AU - Dong, K.
AU - Wu, F.
T2 - INTERNATIONAL JOURNAL OF CONTROL
AB - In this paper, we study stability and performance properties of linear fractional transformation (LFT) parameter-dependent systems using duality theory and tools from convex analysis. A pair of conjugate functions, the convex hull and the maximum of a family of quadratic functions, are used for analysis and synthesis of LFT systems. Sufficient synthesis conditions for both robust state feedback and gain-scheduling output feedback control problems are formulated as a set of linear matrix inequalities (LMIs) with linear search over scalar variables. Finally, a numerical example is used to demonstrate the advantages of the proposed approaches.
DA - 2007/4//
PY - 2007/4//
DO - 10.1080/00207170601080213
VL - 80
IS - 4
SP - 555-568
SN - 1366-5820
ER -
TY - JOUR
TI - Prediction of surface uniformity in woven fabrics through 2-D anisotropy measures, Part II: Simulation and verification of the prediction model
AU - Guenay, M.
AU - Suh, M. W.
AU - Jasper, W. J.
T2 - JOURNAL OF THE TEXTILE INSTITUTE
AB - Abstract Yarn diameter profiles were captured from an online measurement system and then translated into a two-dimensional (2-D) fabric matrix by assigning each point of the yarn to a specific location within a virtual fabric. A method to quantify the anisotropy in fabric nonuniformity was developed by combining the gray-scale image of the 2-D fabric matrix with the newly defined between-area variance curves. The 2-D anisotropy measures thus obtained were found to be highly useful for characterizing certain appearance features of woven fabrics such as vertical or horizontal streaks and random cloudiness. Methods for selecting different shapes of the unit area facilitated comparison of the resulting between-area variance curves, and thus a measure of isotropy in the nonuniformity features of the woven fabrics.
DA - 2007///
PY - 2007///
DO - 10.1533/joti.2005.0234
VL - 98
IS - 2
SP - 117-126
SN - 0040-5000
KW - variance-area curves
KW - anisotropy
KW - surface uniformity
KW - simulation
ER -
TY - JOUR
TI - Prediction of surface uniformity in woven fabrics through 2-D anisotropy measures, Part I: Definitions and theoretical model
AU - Suh, M. W.
AU - Guenay, M.
AU - Jasper, W. J.
T2 - JOURNAL OF THE TEXTILE INSTITUTE
AB - Abstract A method has been developed for analyzing and predicting the surface uniformity of fabrics directly from yarn diameter measurements by using variance-area curves. The variance-length curves were first derived as a function of correlogram obtainable from the neighboring points within a yarn. Then the between-area variance curves were obtained directly from the variance-length curve and a correlation function. The anisotropy of surface irregularity was defined for woven fabrics, and a quantification method was proposed.
DA - 2007///
PY - 2007///
DO - 10.1533/joti.2005.0232
VL - 98
IS - 2
SP - 109-116
SN - 0040-5000
KW - variance-area curves
KW - anisotropy
KW - surface uniformity
ER -
TY - JOUR
TI - Model-based robust control design for magnetostrictive transducers operating in hysteretic and nonlinear regimes
AU - Nealis, James M.
AU - Smith, Ralph C.
T2 - IEEE TRANSACTIONS ON CONTROL SYSTEMS TECHNOLOGY
AB - This paper addresses the development of robust control designs for high-performance smart material transducers operating in nonlinear and hysteretic regimes. While developed in the context of a magnetostrictive transducer used for high-speed, high-accuracy milling, the resulting model-based control techniques can be directly extended to systems utilizing piezoceramic or shape memory alloy compounds due to the unified nature of models used to quantify hysteresis and nonlinearities inherent to all of these materials. When developing models and corresponding inverse filters or compensators, significant emphasis is placed on the utilization of the material's physics to provide the accuracy and efficiency required for real-time implementation of resulting model-based control designs. In the material models, this is achieved by combining energy analysis with stochastic homogenization techniques, whereas the efficiency of forward algorithms is combined with monotonicity properties of the material behavior to provide highly efficient inverse algorithms. These inverse filters are then incorporated in H _{2} and H _{infin} theory to provide robust control algorithms capable of providing high-accuracy tracking even though the actuators are operating in nonlinear and hysteretic regimes. Through numerical examples, it is illustrated that the robust designs incorporating inverse compensators can achieve the required tracking tolerance of 1-2 mum for the motivating milling application, whereas robust designs which treat the uncompensated hysteresis and nonlinearities as unmodeled disturbances cannot achieve design specifications
DA - 2007/1//
PY - 2007/1//
DO - 10.1109/TCST.2006.883235
VL - 15
IS - 1
SP - 22-39
SN - 1558-0865
KW - constitutive nonlinearities
KW - distributed parameter systems
KW - hysteresis
KW - inverse filter
KW - magnetostrictive devices
KW - robust control design
ER -
TY - BOOK
TI - Secure data management in decentralized systems
AB - The field of database security has expanded greatly, with the rapid development of global inter-networked infrastructure. Databases are no longer stand-alone systems accessible only to internal users of organizations. Today, businesses must allow selective access from different security domains. New data services emerge every day, bringing complex challenges to those whose job is to protect data security. The Internet and the web offer means for collecting and sharing data with unprecedented flexibility and convenience, presenting threats and challenges of their own. This book identifies and addresses these new challenges and more, offering solid advice for practitioners and researchers in industry.
DA - 2007///
PY - 2007///
DO - 10.1007/978-0-387-27696-0
PB - New York: Springer
SN - 0387276947
ER -
TY - JOUR
TI - On the impact of quality of protection in wireless local area networks with IP mobility
AU - Agarwal, Avesh K.
AU - Wang, Wenye
T2 - MOBILE NETWORKS & APPLICATIONS
DA - 2007/2//
PY - 2007/2//
DO - 10.1007/s11036-006-0009-6
VL - 12
IS - 1
SP - 93-110
SN - 1572-8153
KW - wireless local area networks
KW - quality of service
KW - quality of protection
KW - security protocols
KW - mobile IP
KW - performance analysis
ER -
TY - JOUR
TI - Direct transcription solution of higher-index optimal control problems and the virtual index
AU - Engelsone, A.
AU - Campbell, S. L.
AU - Betts, J. T.
T2 - APPLIED NUMERICAL MATHEMATICS
AB - Direct transcription methods are a popular approach for solving optimal control problems. They are sometimes able to solve problems that the classical numerical theory would suggest that they cannot solve. The dynamics of an equality constrained optimal control problem form a differential algebraic equation (DAE), and most numerical methods for solving these optimal control problems require solving this DAE for the states and algebraic variables, which would imply that the problem is unsolvable if this DAE is high index. We will demonstrate that direct transcription methods, which use a different approach, can successfully solve some higher index equality constrained optimal control problems and that the role of the index needs reinterpretation when using direct transcription methods. These results and observations have implications for software design and guidance provided to users.
DA - 2007/3//
PY - 2007/3//
DO - 10.1016/j.apnum.2006.03.012
VL - 57
IS - 3
SP - 281-296
SN - 1873-5460
KW - numerical methods
KW - optimal control
KW - direct transcription
ER -
TY - JOUR
TI - Condition estimates for pseudo-arclength continuation
AU - Dickson, K. I.
AU - Kelley, C. T.
AU - Ipsen, I. C. F.
AU - Kevrekidis, I. G.
T2 - SIAM JOURNAL ON NUMERICAL ANALYSIS
AB - We bound the condition number of the Jacobian in pseudo‐arclength continuation problems, and we quantify the effect of this condition number on the linear system solution in a Newton‐GMRES solve. Pseudo‐arclength continuation solves parameter dependent nonlinear equations $G(u,\lambda) = 0$ by introducing a new parameter s, which approximates arclength, and viewing the vector $x = (u,\lambda)$ as a function of s. In this way simple fold singularities can be computed directly by solving a larger system $F(x,s) = 0$ by simple continuation in the new parameter s. It is known that the Jacobian $F_x$ of F with respect to $x=(u,\lambda)$ is nonsingular if the path contains only regular points and simple fold singularities. We introduce a new characterization of simple folds in terms of the singular value decomposition, and we use it to derive a new bound for the norm of $F_x^{-1}$. We also show that the convergence rate of GMRES in a Newton step for $F(x,s)=0$ is essentially the same as that of the original problem $G(u,\lambda)=0$. In particular, we prove that the bounds on the degrees of the minimal polynomials of the Jacobians $F_x$ and $G_u$ differ by at most 2. We illustrate the effectiveness of our bounds with an example from radiative transfer theory.
DA - 2007///
PY - 2007///
DO - 10.1137/060654384
VL - 45
IS - 1
SP - 263-276
SN - 1095-7170
KW - pseudo-arclength continuation
KW - singularity
KW - GMRES
KW - singular vectors
KW - eigenvalues
KW - rank-one update
KW - turning point
KW - simple fold
KW - fold point
KW - limit point
ER -
TY - JOUR
TI - An algebra for commitment protocols
AU - Mallya, Ashok U.
AU - Singh, Munindar P.
T2 - AUTONOMOUS AGENTS AND MULTI-AGENT SYSTEMS
DA - 2007/4//
PY - 2007/4//
DO - 10.1007/s10458-006-7232-1
VL - 14
IS - 2
SP - 143-163
SN - 1573-7454
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33846465461&partnerID=MN8TOARS
KW - commitments
KW - interaction protocols
KW - formal methods
KW - multiagent system modelling and design
ER -
TY - JOUR
TI - A model for life cycle evaluation of highway investments
AU - List, George
T2 - STRUCTURE AND INFRASTRUCTURE ENGINEERING
AB - Sustainable development has added a new dimension to the evaluation of highway capacity investments. It places an emphasis on analyzing the entire life of a facility, from an environmental as well as an economic perspective. This paper presents a way to analyze capacity investments that is consistent with the sustainable development perspective. It departs from the typical approach of focusing on a small set of peak use conditions, often in the design year. It couples economic concepts with a representation of the facility's lifetime use to perform a robust analysis. A freeway facility is used to illustrate the ideas. Principles of engineering economics and life cycle costing help determine what incremental capacity investments would be warranted given postulated or observed use patterns. It is then demonstrated that the findings from this analysis and the principles employed can be applied to a wide range of infrastructure investment decision making situations.
DA - 2007/6//
PY - 2007/6//
DO - 10.1080/15732470600590903
VL - 3
IS - 2
SP - 95-101
SN - 1573-2479
KW - life cycle
KW - infrastructure
KW - economics
ER -
TY - JOUR
TI - A distribution-free tabular CUSUM chart for autocorrelated data
AU - Kim, Seong-Hee
AU - Alexopoulos, Christos
AU - Tsui, Kwok-Leung
AU - Wilson, James R.
T2 - IIE TRANSACTIONS
AB - A distribution-free tabular CUSUM chart called DFTC is designed to detect shifts in the mean of an autocorrelated process. The chart's Average Run Length (ARL) is approximated by generalizing Siegmund's ARL approximation for the conventional tabular CUSUM chart based on independent and identically distributed normal observations. Control limits for DFTC are computed from the generalized ARL approximation. Also discussed are the choice of reference value and the use of batch means to handle highly correlated processes. The performance of DFTC compared favorably with that of other distribution-free procedures in stationary test processes having various types of autocorrelation functions as well as normal or nonnormal marginals.
DA - 2007/3//
PY - 2007/3//
DO - 10.1080/07408170600743946
VL - 39
IS - 3
SP - 317-330
SN - 0740-817X
KW - statistical process control
KW - tabular CUSUM chart
KW - autocorrelated data average run length
KW - distribution-free statistical methods
ER -
TY - JOUR
TI - A compressed primal-dual method for generating bivariate. cubic L-1 splines
AU - Wang, Yong
AU - Fang, Shu-Cherng
AU - Lavery, John E.
T2 - JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS
AB - In this paper, we develop a compressed version of the primal-dual interior point method for generating bivariate cubic L1 splines. Discretization of the underlying optimization model, which is a nonsmooth convex programming problem, leads to an overdetermined linear system that can be handled by interior point methods. Taking advantage of the special matrix structure of the cubic L1 spline problem, we design a compressed primal-dual interior point algorithm. Computational experiments indicate that this compressed primal-dual method is robust and is much faster than the ordinary (uncompressed) primal-dual interior point algorithm.
DA - 2007/4/1/
PY - 2007/4/1/
DO - 10.1016/j.cam.2006.02.005
VL - 201
IS - 1
SP - 69-87
SN - 0377-0427
ER -
TY - JOUR
TI - eQTL Viewer: visualizing how sequence variation affects genome-wide transcription
AU - Zou, W.
AU - Aylor, D. L.
AU - Zeng, Z. B.
T2 - BMC Bioinformatics
DA - 2007///
PY - 2007///
VL - 8
IS - 7
ER -
TY - JOUR
TI - A delayed nonlinear PBPK model for genistein dosimetry in rats
AU - Zagera, Michael G.
AU - Schlosser, Paul M.
AU - Tran, Hien T.
T2 - BULLETIN OF MATHEMATICAL BIOLOGY
AB - Genistein is an endocrine-active compound (EAC) found in soy products. It has been linked to beneficial effects such as mammary tumor growth suppression and adverse endocrine-related effects such as reduced birth weight in rats and humans. In its conjugated form, genistein is excreted in the bile, which is a significant factor in its pharmacokinetics. Experimental data suggest that genistein induces a concentration-dependent suppression of biliary excretion. In this article, we describe a physiologically based pharmacokinetic (PBPK) model that focuses on biliary excretion with the goal of accurately simulating the observed suppression. The mathematical model is a system of nonlinear differential equations with state-dependent delay to describe biliary excretion. The model was analyzed to examine local existence and uniqueness of a solution to the equations. Furthermore, unknown parameters were estimated, and the mathematical model was compared against published experimental data.
DA - 2007/1//
PY - 2007/1//
DO - 10.1007/s11538-006-9068-x
VL - 69
IS - 1
SP - 93-117
SN - 1522-9602
KW - genistein
KW - biliary excretion
KW - pharmacokinetics
KW - delay-differential equations
ER -
TY - JOUR
TI - A Finite Difference Method and Analysis for 2D Nonlinear Poisson–Boltzmann Equations
AU - Li, Zhilin
AU - Pao, C. V.
AU - Qiao, Zhonghua
T2 - Journal of Scientific Computing
DA - 2007/1/31/
PY - 2007/1/31/
DO - 10.1007/s10915-005-9019-y
VL - 30
IS - 1
SP - 61–81
SN - 0885-7474 1573-7691
UR - http://dx.doi.org/10.1007/s10915-005-9019-y
KW - nonlinear Poisson-Boltzmann equation
KW - exterior problem
KW - immersed interface method
KW - monotone iterative method
ER -