TY - CHAP TI - On the design of dynamic reconfiguration policies for broadcast WDM networks AU - Baldine, I AU - Rouskas, GN AU - Senoir, JM AU - Qiao, C T2 - All-Optical Networking: Architecture, Control, and Management Issues AB - We study the issues arising when considering the problem of reconfiguring broadcast optical networks in response to changes in the traffic patterns. Although the ability to dynamically optimize the network under changing traffic conditions has been recognized as one of the key features of multiwavelength optical networks, this is the first in-depth study of the trade-offs involved in carrying out the reconfiguration process. Our contribution is three-fold. First, we identify the degree of load balancing and the number of retunings as two important, albeit conflicting, objectives in the design of reconfiguration policies. Second, we formulate the problem as a Markovian Decision Process and we develop a systematic and flexible framework in which to view and contrast reconfiguration policies. Third, we also show how an appropriate selection of reward and cost functions can be used to achieve the desired balance among various performance criteria of interest. Our work demonstrates that it is practical to apply Markov Decision Process theory to obtain optimal reconfiguration policies even for networks of large size. The advantages of optimal policies over a class of threshold-based policies are also illustrated through numerical results. PY - 1998/// DO - 10.1117/12.327053 VL - 3531 SP - 146-157 PB - SE - ER - TY - CHAP TI - Dynamic load balancing in broadcast WDM networks with tuning latencies AU - Baldine, I AU - Rouskas, GN AU - IEEE T2 - Ieee Infocom '98 - the Conference on Computer Communications, Vols. 1-3 PY - 1998/// SP - 78-85 PB - SE - ER - TY - CONF TI - Predictable Scheduling of a Single Machine with Breakdowns and Sensitive Jobs AU - O’Donovan, R. AU - McKay, K.N. AU - Uzsoy, R. T2 - INFORMS National Meeting C2 - 1998/4// CY - Montreal, Canada DA - 1998/4// PY - 1998/4// ER - TY - CONF TI - Empirical Evaluation of Heuristics: A Tutorial AU - Rardin, R.L. AU - Uzsoy, R. T2 - INFORMS National Meeting C2 - 1998/4// CY - Montreal, Canada DA - 1998/4// PY - 1998/4// ER - TY - CONF TI - Decomposition Procedures for Scheduling Complex Job Shops AU - Demirkol, E. AU - Uzsoy, R. AU - Wang, C.S. T2 - Sixth International Workshop on Project Management and Scheduling C2 - 1998/7// C3 - Proceedings of the Sixth International Workshop on Project Management and Scheduling DA - 1998/7// PY - 1998/7// ER - TY - JOUR TI - Supply Chain Management for Companies with Product Recovery and Remanufacturing Capability AU - Uzsoy, R. AU - Venkatachalam, G. T2 - International Journal of Environmentally Conscious Design and Manufacturing DA - 1998/// PY - 1998/// VL - 7 SP - 59–72 ER - TY - SOUND TI - Predictable Scheduling of Job Shops Subject To Machine Breakdowns AU - Uzsoy, R. AU - Mehta, S.V. DA - 1998/3// PY - 1998/3// ER - TY - SOUND TI - A Senior Design Course with Industrial Experience AU - Uzsoy, R. DA - 1998/4// PY - 1998/4// ER - TY - SOUND TI - Management of Spare Parts Inventories in a Wafer Fabrication Facility AU - Teyner, T. AU - Uzsoy, R. DA - 1998/5// PY - 1998/5// ER - TY - SOUND TI - Maintenance Management Problems in a Semiconductor Wafer Fabrication Facility AU - Uzsoy, R. DA - 1998/11// PY - 1998/11// ER - TY - CONF TI - Effects of epitaxial silicon technology on the manufacturing performance of wafer fabrication lines AU - Hughes, J.C. AU - Neudeck, G.W. AU - Uzsoy, R. T2 - Twenty Third IEEE/CPMT International Electronics Manufacturing Technology Symposium. 1998 IEMT Symposium AB - This paper evaluates the manufacturing benefits of silicon selective epitaxial growth (SEG) as a front-end device isolation fabrication process. The technology is evaluated in two different ways. First, the cost of ownership (COO) of the equipment is used to obtain a cost of process (COP) for SEG and compared to the current alternatives, which are local oxidation of silicon (LOCOS) and shallow trench isolation (STI). Results of the processes, up to the point where the CMOS MOSFETs are produced, show that cost reductions using SEG was more than 22% compared to LOCOS and 49% compared to STI. The second evaluation approach examines the effects of the three processes on the mean and variance of fabrication cycle time using queuing network models. These results indicate that the mean cycle time for the portion of the line being considered could drop by as much as one third when the dielectric isolation by SEG (DI-SEG) process is implemented. Significant increases in line yield may also result. C2 - 1998/// C3 - Twenty Third IEEE/CPMT International Electronics Manufacturing Technology Symposium (Cat. No.98CH36205) DA - 1998/// PY - 1998/10/19/ DO - 10.1109/iemt.1998.731090 PB - IEEE UR - http://dx.doi.org/10.1109/iemt.1998.731090 ER - TY - JOUR TI - Control of a batch-processing machine: A computational approach AU - Avramidis, A. N. AU - Healy, K.J. AU - Uzsoy, R. T2 - International Journal of Production Research AB - Batch processing machines, where a number of jobs are processed simultaneously as a batch, occur frequently in semiconductor manufacturing environments, particularly at diffusion in wafer fabrication and at burn-in in final test. In this paper we consider a batch-processing machine subject to uncertain (Poisson) job arrivals. Two different cases are studied: (1) the processing times of batches are independent and identically distributed (IID), corresponding to a diffusion tube; and (2) the processing time of each batch is the maximum of the processing times of its constituent jobs, where the processing times of jobs are IID, modelling a burn-in oven. We develop computational procedures to minimize the expected long-run-average number of jobs in the system under a particular family of control policies. The control policies considered are threshold policies, where processing of a batch is initiated once a certain number of jobs have accumulated in the system. We present numerical examples of our methods and verify their accuracy using simulation. DA - 1998/11// PY - 1998/11// DO - 10.1080/002075498192355 VL - 36 IS - 11 SP - 3167-3181 J2 - International Journal of Production Research LA - en OP - SN - 0020-7543 1366-588X UR - http://dx.doi.org/10.1080/002075498192355 DB - Crossref ER - TY - JOUR TI - Benchmarks for shop scheduling problems AU - Demirkol, Ebru AU - Mehta, Sanjay AU - Uzsoy, Reha T2 - European Journal of Operational Research AB - In this paper we present extensive sets of randomly generated test problems for the problems of minimizing makespan (Cmax) and maximum lateness (Lmax) in flow shops and job shops. The 600 problems include three different types of routings, four different due date configurations and a variety of problem sizes. The problems, as well as the best existing solution and a lower bound on the optimal value are available on the world-wide web. DA - 1998/8// PY - 1998/8// DO - 10.1016/s0377-2217(97)00019-2 VL - 109 IS - 1 SP - 137-141 J2 - European Journal of Operational Research LA - en OP - SN - 0377-2217 UR - http://dx.doi.org/10.1016/s0377-2217(97)00019-2 DB - Crossref KW - combinatorial optimization KW - scheduling KW - benchmarks ER - TY - JOUR TI - Predictable scheduling of a job shop subject to breakdowns AU - Mehta, S.V. AU - Uzsoy, R.M. T2 - IEEE Transactions on Robotics and Automation AB - Schedule modification may delay or render infeasible the execution of external activities planned on the basis of the predictive schedule. Thus it is of interest to develop predictive schedules which can absorb disruptions without affecting planned external activities, while maintaining high shop performance. We present a predictable scheduling approach where the predictive schedule is built with such objectives. The procedure inserts additional idle time into the schedule to absorb the impacts of breakdowns. The amount and location of the additional idle time is determined from the breakdown and repair distributions as well as the structure of the predictive schedule. The effects of disruptions on planned support activities are measured by the deviations of job completion times in the realized schedule from those in the predictive schedule. We apply our approach to minimizing maximum lateness in a job shop environment with random machine breakdowns, and show that it provides high predictability with minor sacrifices in shop performance. DA - 1998/6// PY - 1998/6// DO - 10.1109/70.678447 VL - 14 IS - 3 SP - 365-378 J2 - IEEE Trans. Robot. Automat. OP - SN - 1042-296X UR - http://dx.doi.org/10.1109/70.678447 DB - Crossref KW - job shop KW - predictable scheduling KW - rescheduling KW - scheduling KW - uncertainties ER - TY - JOUR TI - Maintenance scheduling and staffing policies in a wafer fabrication facility AU - Mosley, S.A. AU - Teyner, T. AU - Uzsoy, R.M. T2 - IEEE Transactions on Semiconductor Manufacturing AB - We examine how to reduce the adverse effects of machine down time by prioritizing production equipment for attention by a limited number of maintenance personnel. The maintenance scheduling policies use system information to determine which machines are the most critical at a given time. This information includes repair times, queue lengths, due dates, available capacity, and steady-state utilizations. The effects of different staffing levels are also considered. A discrete-event simulation model of a wafer fabrication facility is used to examine the performance of the different policies. Results indicate that the choice of maintenance scheduling policy can significantly affect system performance under restrictive staffing-levels. Moreover, factory performance is shown to be sensitive to small changes in staffing level. DA - 1998/5// PY - 1998/5// DO - 10.1109/66.670182 VL - 11 IS - 2 SP - 316-323 J2 - IEEE Trans. Semicond. Manufact. OP - SN - 0894-6507 UR - http://dx.doi.org/10.1109/66.670182 DB - Crossref KW - maintenance management KW - scheduling KW - staffing KW - wafer fabrication ER - TY - JOUR TI - Minimizing total tardiness on a batch processing machine with incompatible job families AU - Mehta, Sanjay V. AU - Uzsoy, Reha T2 - IIE Transactions AB - Abstract Motivated by an application in semiconductor manufacturing, we study the problem of minimizing total tardiness on a batch processing machine with incompatibl8e job families, where all jobs of the same family have identical processing times and jobs of different families cannot be processed together. We present a dynamic programming algorithm which has polynomial time complexity when the number of job families and the batch machine capacity are fixed. We also examine various heuristic solution procedures which can provide near optimal solutions in a reasonable amount of computation time. DA - 1998/2// PY - 1998/2// DO - 10.1080/07408179808966448 VL - 30 IS - 2 SP - 165-178 J2 - IIE Transactions LA - en OP - SN - 0740-817X 1545-8830 UR - http://dx.doi.org/10.1080/07408179808966448 DB - Crossref ER - TY - JOUR TI - Scheduling a single batch processing machine with secondary resource constraints AU - Kempf, Karl G. AU - Uzsoy, Reha AU - Wang, Cheng-Shuo T2 - Journal of Manufacturing Systems AB - This paper studies the problems of minimizing total completion time (ΣCi) and makespan (Cmax) on a single batch processing machine with job families and secondary resource constraints. The motivation for this problem is the burn-in operation in the final testing stage of semiconductor manufacturing, where both oven capacity and the number of boards available may constrain scheduling decisions. Because both problems are NP-hard, integer programming formulations are developed for special cases and are then used to develop heuristics. Extensive computational experiments show that the heuristics are capable of consistently obtaining good solutions in modest CPU times. DA - 1998/1// PY - 1998/1// DO - 10.1016/s0278-6125(98)80008-3 VL - 17 IS - 1 SP - 37-51 J2 - Journal of Manufacturing Systems LA - en OP - SN - 0278-6125 UR - http://dx.doi.org/10.1016/s0278-6125(98)80008-3 DB - Crossref KW - scheduling KW - semiconductor manufacturing KW - batch processing machines KW - heuristics ER - TY - JOUR TI - A capacity allocation problem with integer side constraints AU - Toktay, L.Beril AU - Uzsoy, Reha T2 - European Journal of Operational Research AB - We address a capacity allocation problem arising as a subproblem of an artificial intelligence-based scheduling system for a semiconductor wafer fabrication facility. Tooling constraints, setup considerations and differences in machine capabilities are taken into account. Focusing on the objectives of maximizing throughput and minimizing deviation from predetermined production goals, we formulate the problem as a maximum flow problem on a bipartite network with integer side constraints and develop efficient heuristics which obtain near-optimal solutions in negligible computation time. The type of network flow problem we study has not been addressed in the literature to date and is of considerable theoretical interest. From a practical point of view, the network flow model of the problem and the algorithms developed for its solution are applicable to a wide range of production settings. DA - 1998/8// PY - 1998/8// DO - 10.1016/s0377-2217(98)80011-8 VL - 109 IS - 1 SP - 170-182 J2 - European Journal of Operational Research LA - en OP - SN - 0377-2217 UR - http://dx.doi.org/10.1016/s0377-2217(98)80011-8 DB - Crossref KW - scheduling KW - network flows KW - semiconductor manufacturing ER - TY - CONF TI - Wetlands Mitigation Optimization Model Using NC Crews AU - Gainey, K.W. AU - Roise, J.P. T2 - Connections 98: National Conference on Transportation, Wetlands and the Natural Environment C2 - 1998/9/16/ CY - New Bern, NC DA - 1998/9/16/ PY - 1998/9/16/ ER - TY - CONF TI - A Tactical Level Approach to Lumber Manufacturing Decisions: use of a Computer-Aided Sawing Pattern Design Program AU - Roise, J.P. T2 - INFORMS National Conference C2 - 1998/10/25/ CY - Seattle, WA DA - 1998/10/25/ PY - 1998/10/25/ ER - TY - RPRT TI - If a matrix has a single eigenvalue, how sensitive is this eigenvalue? AU - Cho, G.E. AU - Ipsen, I.C.F. A3 - Center for Research in Scientific Computation, Department of Mathematics, North Carolina State University DA - 1998/// PY - 1998/// M1 - CRSC-TR98-8 M3 - Technical Report PB - Center for Research in Scientific Computation, Department of Mathematics, North Carolina State University SN - CRSC-TR98-8 ER - TY - RPRT TI - A note on the field of values of non-normal matrices AU - Ipsen, I.C.F. A3 - Center for Research in Scientific Computation, Department of Mathematics, North Carolina State University DA - 1998/// PY - 1998/// M1 - CRSC-TR98-26 M3 - Technical Report PB - Center for Research in Scientific Computation, Department of Mathematics, North Carolina State University SN - CRSC-TR98-26 ER - TY - RPRT TI - A different approach to bounding the minimal residual norm in Krylov methods AU - Ipsen, I.C.F. A3 - Center for Research in Scientific Computation, Department of Mathematics, North Carolina State University DA - 1998/// PY - 1998/// M1 - CRSC-TR98-19 M3 - Technical Report PB - Center for Research in Scientific Computation, Department of Mathematics, North Carolina State University SN - CRSC-TR98-19 ER - TY - RPRT TI - Multicustomer Due-Date Bargainer AU - Nuttle, H.L.W. AU - Fang, S-C AU - Wang, D-W AU - Donovan, M. A3 - North Carolina State University DA - 1998/10// PY - 1998/10// M3 - software PB - North Carolina State University ER - TY - JOUR TI - Theoretical and numerical analysis on a thermo-elastic system with discontinuities AU - Li, Zhilin AU - Wang, Deshen AU - Zou, Jun T2 - Journal of Computational and Applied Mathematics AB - A second-order accurate numerical scheme is proposed for a thermo-elastic system which models a bar made of two distinct materials. The physical parameters involved may be discontinuous across the joint of the two materials, where there might be also singular heat and/or force sources. The solution components, the temperature and the displacement, may change rapidly across the joint. By transforming the system into a different one, time-marching schemes can be used for the new system which is well posed. The immersed interface method is employed to deal with the discontinuities of the coefficients and the singular sources. The proposed numerical method can fit both explicit and implicit formulation. For the implicit version, a stable and fast prediction-correction scheme is also developed. Convergence analysis shows that our method is second-order accurate at all grid points in spite of the discontinuities across the interface. Numerical experiments are performed to support the theoretical analysis in this paper. DA - 1998/5// PY - 1998/5// DO - 10.1016/s0377-0427(98)00044-2 VL - 92 IS - 1 SP - 37-58 J2 - Journal of Computational and Applied Mathematics LA - en OP - SN - 0377-0427 UR - http://dx.doi.org/10.1016/s0377-0427(98)00044-2 DB - Crossref KW - mixed type system KW - discontinuous coefficients KW - Dirac delta function KW - finite difference KW - semi-implicit prediction-correction scheme KW - error analysis ER - TY - JOUR TI - The scientific theory-building process: A primer using the case of TQM AU - Handfield, R.B. AU - Melnyk, S.A. T2 - Journal of Operations Management AB - Abstract As Operations Management (OM) researchers begin to undertake and publish more empirical research, there is a need to understand the nature of the scientific theory‐building process implicit in this activity. This tutorial presents a process map approach to this process. We begin by defining the nature of scientific knowledge, and proceed through the stages of the theory‐building process, using illustrations from OM research in Total Quality Management. The tutorial ends with a discussion of the criteria for OM journal reviewers to consider in evaluating theory‐driven empirical research, and suggests a number of OM topic areas that require greater theory development. DA - 1998/// PY - 1998/// DO - 10.1016/s0272-6963(98)00017-5 VL - 16 IS - 4 SP - 321-339 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032118213&partnerID=MN8TOARS ER - TY - CONF TI - TQM dynamics - an empirical study of TQM practice and performance AU - Das, Ajay AU - Handfield, Robert B. AU - Calantone, Roger J. AU - Ghosh, Soumen C2 - 1998/// C3 - Proceedings - Annual Meeting of the Decision Sciences Institute DA - 1998/// VL - 3 SP - 1620-1622 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0031634149&partnerID=MN8TOARS ER - TY - CONF TI - Supplier development: An empirical investigation AU - Krause, Daniel R. AU - Handfield, Robert B. AU - Scannell, Thomas V. C2 - 1998/// C3 - Proceedings - Annual Meeting of the Decision Sciences Institute DA - 1998/// VL - 3 SP - 1275-1277 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0031639017&partnerID=MN8TOARS ER - TY - JOUR TI - Success factors in strategic supplier alliances: The buying company perspective AU - Monczka, R.M. AU - Petersen, K.J. AU - Handfield, R.B. AU - Ragatz, G.L. T2 - Decision Sciences AB - ABSTRACT The emerging area of supply chain alliances has received considerable attention in the academic and managerial press, yet there are many unanswered questions regarding the dynamics of such relationships. A number of such fundamental issues drive this research initiative, including how alliances are developed, their key success factors, and the specific benefits to be achieved. The study begins by establishing a definition of strategic supplier alliances, based on a comparison of both theoretical and managerial descriptions. The critical antecedents associated with the success of strategic supplier alliances are next developed, and the magnitude of the effect of these factors on partnership success is assessed. The analysis employs both qualitative and quantitative data, collected through an electronic network of over 200 companies, as part of an ongoing benchmarking initiative in supply chain management. From the perspective of the buying company in the alliance, the following attributes of supplier alliances were found to be significantly related to partnership success: trust and coordination, interdependence, information quality and participation, information sharing, joint problem solving, avoiding the use of severe conflict resolution tactics, and the existence of a formal supplier/commodity alliance selection process. Resource commitment and smoothing over problems were found to be poor predictors of alliance success. The implications of these results for managerial decision making in supplier alliance development are discussed. DA - 1998/// PY - 1998/// DO - 10.1111/j.1540-5915.1998.tb01354.x VL - 29 IS - 3 SP - 553-577 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032272611&partnerID=MN8TOARS KW - linear regression KW - purchasing KW - and supply chain management ER - TY - JOUR TI - Stages of global sourcing strategy evolution: An exploratory study AU - Bozarth, C. AU - Handfield, R. AU - Das, A. T2 - Journal of Operations Management AB - Abstract This paper analyzes the interrelationships between international sourcing decisions, sourcing strategies, and supplier performance. We first discuss the effect of global competition on the need for firms to seek international suppliers, and present a number of taxonomies that describe the evolution of global supply base development. The deployment of different commodity strategies (e.g., information sharing, single vs. multiple sourcing, contracts, and partnering) in conjunction with international sourcing is also reviewed. In the second half of the paper, we examine a set of international sourcing practices from a sample of 55 US manufacturing firms. Results suggest that US purchasing professionals are not spending as much time managing the ongoing buyer–supplier relationship as they are making the initial purchasing decision. This gap between ‘prescription’ and ‘practice’ represents both a competitive opportunity and threat for manufacturers. DA - 1998/// PY - 1998/// DO - 10.1016/s0272-6963(97)00040-5 VL - 16 IS - 2-3 SP - 241-255 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032066374&partnerID=MN8TOARS ER - TY - CONF TI - Process model of successful supplier integration into new product/process/service development AU - Ragatz, Gary L. AU - Handfield, Robert B. AU - Petersen, Kenneth J. AU - Monczka, Robert M. C2 - 1998/// C3 - Proceedings - Annual Meeting of the Decision Sciences Institute DA - 1998/// VL - 3 SP - 1364-1366 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0031637711&partnerID=MN8TOARS ER - TY - JOUR TI - May you live in interesting times...the emergence of theory-driven empirical research AU - Melnyk, Steven A. AU - Handfield, Robert B. T2 - Journal of Operations Management AB - Journal of Operations ManagementVolume 16, Issue 4 p. 311-319 Preface May you live in interesting times…the emergence of theory-driven empirical research Steven A Melnyk, Steven A Melnyk The Department of Marketing and Supply Chain Management, Michigan State University, East Lansing, MI, USASearch for more papers by this authorRobert B Handfield, Robert B Handfield The Department of Marketing and Supply Chain Management, Michigan State University, East Lansing, MI, USASearch for more papers by this author Steven A Melnyk, Steven A Melnyk The Department of Marketing and Supply Chain Management, Michigan State University, East Lansing, MI, USASearch for more papers by this authorRobert B Handfield, Robert B Handfield The Department of Marketing and Supply Chain Management, Michigan State University, East Lansing, MI, USASearch for more papers by this author First published: 25 November 1998 https://doi.org/10.1016/S0272-6963(98)00027-8Citations: 52 Corresponding author. 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Learn more.Copy URL Citing Literature Volume16, Issue4July 1998Pages 311-319 RelatedInformation DA - 1998/// PY - 1998/// DO - 10.1016/S0272-6963(98)00027-8 VL - 16 IS - 4 SP - 311-319 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032116183&partnerID=MN8TOARS ER - TY - CONF TI - Literature review of Environmentally Responsible Manufacturing AU - Curkovic, Sime AU - Handfield, Rob AU - Melnyk, Steve AU - Sroufe, Rob C2 - 1998/// C3 - Proceedings - Annual Meeting of the Decision Sciences Institute DA - 1998/// VL - 1 SP - 33-35 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0031646174&partnerID=MN8TOARS ER - TY - CONF TI - Green supply chain: Integrating suppliers into environmental management processes AU - Walton, Steve V. AU - Handfield, Robert B. AU - Melnyk, Steven A. C2 - 1998/// C3 - Proceedings - Annual Meeting of the Decision Sciences Institute DA - 1998/// VL - 3 SP - 1114-1116 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0031629406&partnerID=MN8TOARS ER - TY - JOUR TI - Enhancing the firm’s performance through quality and supply base management: An empirical study AU - Tan, K.C. AU - Handfield, R.B. AU - Krause, D.R. T2 - International Journal of Production Research AB - Over the past ten years, both total quality management and supply base management have become significant strategic tools for firms that are striving to achieve competitive success. This study examines firms' operational quality approaches, supplier evaluation practices, and supply base management activities, and relates these strategic initiatives to firm performance. Hypotheses were tested through the use of bivariate correlation, factor analysis and multiple regression analysis of survey data from a cross-industry sample of quality directors and vice presidents in US firms. While many strategic quality approaches and supply base management tools are positively correlated with firm performance, our results show that quality management and supply base management techniques and tools must be implemented conjointly to achieve superior financial and business performance. The implication is that managers must seek to integrate the activities of quality assurance with those of purchasing and materials management. DA - 1998/// PY - 1998/// DO - 10.1080/002075498192490 VL - 36 IS - 10 SP - 2813-2837 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032188660&partnerID=MN8TOARS ER - TY - CONF TI - Enhancing firm's performance through quality and supply base management: An empirical study AU - Tan, Keah Choon AU - Handfield, Robert B. AU - Krause, Daniel R. C2 - 1998/// C3 - Proceedings - Annual Meeting of the Decision Sciences Institute DA - 1998/// VL - 3 SP - 1659-1661 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0031629431&partnerID=MN8TOARS ER - TY - JOUR TI - An empirical investigation of supplier development: Reactive and strategic processes AU - Krause, D.R. AU - Handfield, R.B. AU - Scannell, T.V. T2 - Journal of Operations Management AB - Abstract As firms continue to focus on core competencies and outsource non‐core products and services to external suppliers, supply chain management is increasingly viewed as a source of competitive advantage. However, if the supply chain is to be a source of competitive advantage, suppliers' performance must be managed and developed to meet the needs of the buying firm. In an exploratory study based on data collected from 84 companies, the authors develop a process model for supplier development. Using this process model as a framework, the authors then compare two approaches buying firms use in supplier development: (1) reactive efforts to increase the performance of laggard suppliers, and (2) strategic efforts to increase the capabilities of the supply base to enhance the buying firm's long‐term competitive advantage. Strategic efforts were found to significantly increase the buying company's involvement in suppliers' processes, and required greater dedication of resources, personnel and communication. DA - 1998/// PY - 1998/// DO - 10.1016/S0272-6963(98)00030-8 VL - 17 IS - 1 SP - 39-58 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032295038&partnerID=MN8TOARS ER - TY - RPRT TI - Principles of Standardization AU - Singh, Munindar P. A3 - Foundation of Intelligent Physical Agents (FIPA) DA - 1998/1// PY - 1998/1// PB - Foundation of Intelligent Physical Agents (FIPA) ER - TY - BOOK TI - Book review of Michael Schroeder, Autonomous, Model-Based Diagnosis Agents AU - Singh, Munindar P. AU - Schroeder, Michael DA - 1998/12// PY - 1998/12// SE - 39 ER - TY - BOOK TI - Intelligent Agents IV Agent Theories, Architectures, and Languages T2 - Lecture Notes in Computer Science A3 - Singh, Munindar P. A3 - Rao, Anand A3 - Wooldridge, Michael J. DA - 1998/// PY - 1998/// DO - 10.1007/bfb0026744 M1 - 1365 PB - Springer SN - 9783540641629 9783540696964 UR - http://dx.doi.org/10.1007/bfb0026744 ER - TY - CHAP TI - Multiagent systems in information-rich environments AU - Huhns, Michael N. AU - Singh, Munindar P. T2 - Cooperative Information Agents II Learning, Mobility and Electronic Commerce for Information Discovery on the Internet AB - Information-rich environments are the open environments that characterize most of the modern applications of computing technology. The applications include ubiquitous information access, electronic commerce, virtual enterprises, logistics, and sensor integration, to name but a few. These applications differ from conventional database applications not only in the nature and variety of information they involve, but also in including a significant component that is beyond the information system per se: the creation, transformation, use, and ultimate fate of information. The environments are typified only by the large amounts and varieties of information they include, and whose effective and efficient management is key to the above applications. Multiagent systems (MAS) are an important paradigm for building complex information systems, especially cooperative ones. We describe how cooperative information system architectures have evolved a set of common types of computational agents. We also describe two approaches that address complementary aspects of MAS construction. PY - 1998/// DO - 10.1007/bfb0053676 SP - 79-93 OP - PB - Springer Berlin Heidelberg SN - 9783540646761 9783540691099 UR - http://dx.doi.org/10.1007/bfb0053676 DB - Crossref ER - TY - CONF TI - Fusing a hyper-ellipsoid clustering Kohonen network with the Julier-Uhlmann-Kalman filter for autonomous mobile robot map building and tracking AU - Janet, J.A. AU - White, M.W. AU - Kay, M.G. AU - Sutton, J.C. AU - Brickley, J.J. AB - We fuse a self-organizing hyperellipsoid clustering (HEC) Kohonen neural network with the Julier-Uhlmann-Kalman filter (JUKF) to perform map building and low-level position estimation. The HEC Kohonen uses the Mahalanobis distance to learn elongated shapes (typical of sonar data) and obtain a stochastic measurement of data-node association. The number of nodes is regulated by measuring how well a node model matches its associated data. The HEC Kohonen can handle high-dimensional problems and can be generalized to other pattern recognition problems. The JUKF compliments the HEC Kohonen in that it performs low-level (nonlinear) tracking more efficiently and more accurately than the extended Kalman filter. By estimating and propagating error covariances through system transformations, the JUKF eliminates the need to derive Jacobian matrices. The inclusion of stochastic information inherent to the HEC map renders the JUKF an excellent tool for our HEC-based map building, position estimation, motion planning and low-level tracking. C2 - 1998/// C3 - Proceedings - IEEE International Conference on Robotics and Automation DA - 1998/// DO - 10.1109/ROBOT.1998.677301 VL - 2 SP - 1405-1410 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0031637149&partnerID=MN8TOARS ER - TY - JOUR TI - Workflow agents T2 - IEEE Internet Computing DA - 1998/// PY - 1998/// UR - https://publons.com/publon/21294538/ ER - TY - JOUR TI - Workflow agents AU - Huhns, M.N. AU - Singh, M.P. T2 - IEEE Internet Computing AB - Software agents as user agents, resource agents, and brokers may be able to enhance usefulness of workflow applications. Workflow technology is important to network computing because workflows exist naturally wherever distributed resources are interrelated. The problem with current workflow technology is that it is often too rigid. The lack of freedom accorded to human participants causes workflow management systems to appear unfriendly. As a result, they are often ignored or circumvented. This rigidity also causes productivity losses by making it harder to accommodate the flexible, ad hoc reasoning of human intelligence. Another challenge is that system requirements are rarely static. Software agents promise to address these challenges. The roles of greatest interest to a workflow setting are user agents, resource agents, and brokers. When a workflow is constituted in terms of distinct roles that agents can instantiate, the agents can be set up to respect the constraints of their users and resources. User agents negotiate with one another and with resource agents to ensure that global constraints are not violated and that global efficiencies can be achieved. Agents can include functionality to identify different kinds of exception conditions and react appropriately, possibly by negotiating a special sequence of actions. More importantly, agents can learn from repeated instances of the same kinds of exceptions. With this learning ability, agents can process the updated set of constraints when system requirements change. DA - 1998/// PY - 1998/// DO - 10.1109/4236.707813 VL - 2 IS - 4 SP - 94-96 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0345046978&partnerID=MN8TOARS ER - TY - JOUR TI - Developing formal specifications to coordinate heterogeneous autonomous agents T2 - International Conference on Multi-agent Systems, Proceedings AB - We have been developing an approach for the distributed coordination of heterogeneous, autonomous agents. This approach takes as input (a) agent skeletons, giving compact descriptions of the given agents in terms of their events that are significant for coordination, as well as (b) relationships among the events occurring in these skeletons. A natural question is how may the skeletons and relationships be produced in the first place. Parunak (1996) proposed a methodology for designing multiagent systems based on Dooley graphs (1976) from discourse analysis. We show how with a few key modifications, Dooley graphs can also be used to generate the skeletons and relationships required for coordination. This combines the benefits of an intuitive methodology with a formal and distributed framework for developing multiagent systems from autonomous agents. DA - 1998/// PY - 1998/// DO - 10.1109/ICMAS.1998.699063 UR - https://publons.com/publon/21294534/ ER - TY - JOUR TI - The intentions of teams: Team structure, endodeixis, and exodeixis T2 - ECAI 1998: 13TH EUROPEAN CONFERENCE ON ARTIFICIAL INTELLIGENCE, PROCEEDINGS DA - 1998/// PY - 1998/// UR - https://publons.com/publon/21294546/ ER - TY - JOUR TI - Intelligent Agents IV - Agent Theories, Architectures, and Languages - 4th International Workshop, ATAL'97, Providence, Rhode Island, USA, July 24-26, 1997 - Proceedings - Introduction T2 - Lecture Notes in Computer Science DA - 1998/// PY - 1998/// UR - https://publons.com/publon/21294544/ ER - TY - JOUR TI - Personal assistants AU - Huhns, M.N. AU - Singh, M.P. T2 - IEEE Internet Computing AB - Already there are simple personal agents to help with some of our shopping. There are agents to track stocks in our portfolios, advise us on how to use particular software products, and arrange meetings within corporate workgroups. However, none of these agents takes more than one aspect of our activities into account, nor do they adapt easily to our preferences. Personal assistants, on the other hand, are agents that can represent individuals on the Web. They help users in their day-to-day activities, especially those involving information retrieval, negotiation, or coordination. A personal assistant might schedule a meeting and then, based on the meeting location, find the nearest babysitting service or the ATM with the lowest transaction fee. The paper discusses the interaction framework, negotiation, profiles and standards. DA - 1998/// PY - 1998/// DO - 10.1109/4236.722236 VL - 2 IS - 5 SP - 90-92 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-2442709095&partnerID=MN8TOARS ER - TY - JOUR TI - Agent information contracts within virtual private networks T2 - Third Ieee International High-assurance Systems Engineering Symposium, Proceedings AB - Virtual enterprises are being built on an Internet backbone, for which security provisioning is an obvious first concern. However, additional services need provisioning as well. For instance, contracted arrangements for quality inspection, notification of delay, and other such coordinations can be provided by semi-autonomous agent-based services. We introduce information contracts, which specify the commitments of ContractAgents to each other. Based on human-readable contract templates with fill-in-the-black terms, ContractAgents manage the negotiation stage between user specialists and then operationalize and ensure these commitments during enactment. Building on the idea of an agent-based sphere of commitments (SoComs) to overcome weaknesses in extended transaction processing and traditional workflow management, we show how ContractAgents also need to be positioned within the security architecture of virtual private networks. The standardization of contracts, SoCom servers, and operationalized commitments can then provide a basis for compliance checks by trusted third parties and oversight authorities. DA - 1998/// PY - 1998/// DO - 10.1109/HASE.1998.731634 UR - https://publons.com/publon/21294543/ ER - TY - JOUR TI - A customizable coordination service for autonomous agents T2 - Lecture Notes in Computer Science AB - We address the problem of constructing multiagent systems by coordinating autonomous agents, whose internal designs may not be fully known. We develop a customizable coordination service that (a) takes declarative specifications of the desired interactions, and (b) automatically enacts them. Our approach is based on temporal logic, and has a rigorous semantics and a naturally distributed implementation. DA - 1998/// PY - 1998/// DO - 10.1007/BFB0026752 UR - https://publons.com/publon/21294545/ ER - TY - JOUR TI - Anthropoid agents AU - Huhns, M.N. AU - Singh, M.P. T2 - IEEE Internet Computing AB - In the study of agents on the Internet, we often ascribe to them human qualities, such as beliefs and intentions. These qualities are best understood as metaphors that give developers a way to talk about and design the capabilities and applications of agents. Despite all the progress in computing, users have been slow to accept the technology. They have often accepted what was thrown at them, but only under economic duress. Bringing the technology closer to their emotional needs might ease this resistance. So how can we put a human face on computing? Maybe by putting an animated face on it! Thus, an interface may consist of an agent, which has an explicit presence (for example, as an on-screen animated figure) and appears to have a personality. In computer human interfaces, especially for education and commerce where a large variety of people must deal with computers, an anthropoid agent might be more inviting. Depending on the situation, the agent might appear shy, friendly, stern, or knowledgeable. For example, people might better accept advice offered politely by a shy agent, or heed warnings uttered seriously by a stern agent. And they might be more likely to purchase goods or services offered by a friendly, knowledgeable agent that could appear empathetic to their needs. DA - 1998/// PY - 1998/// DO - 10.1109/4236.656099 VL - 2 IS - 1 SP - 94-95 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0011365415&partnerID=MN8TOARS ER - TY - CONF TI - New Analysis of the {N}elder-{M}ead Algorithm AU - Kelley, C T A2 - Scott, D W C2 - 1998/// C3 - Proceedings of the 29th Symposium on the Interface DA - 1998/// SP - 407 ER - TY - JOUR TI - Robust Solution of {R}ichards' Equation for Non-Uniform Porous Media AU - Miller, C T AU - Williams, G A AU - Kelley, C T AU - Tocci, M D T2 - Water Resources Research DA - 1998/// PY - 1998/// VL - 34 SP - 2599-2610 ER - TY - CONF TI - The Simplex Gradient and Noisy Optimization Problems AU - Bortz, D M AU - Kelley, C T A2 - Borggaard, J T A2 - Burns, J A2 - Cliff, E A2 - Schreck, S C2 - 1998/// C3 - Computational Methods in Optimal Design and Control DA - 1998/// VL - 24 SP - 77-90 PB - Birkh{ä}user, Boston ER - TY - CONF TI - Efficient and robust numerical modeling of variably saturated flow in layered porous media AU - Miller, C T AU - Williams, G A AU - Kelley, C T A2 - Burganos, V N A2 - Karatzas, G P A2 - Payatakes, A C A2 - Brebbia, C A A2 - Gray, W G A2 - Pinder, G F C2 - 1998/// C3 - XII Conference on Computational Methods in Water Resources, Crete, Greece DA - 1998/// VL - 1 SP - 151-158 ER - TY - RPRT TI - Optimization of Automotive Valve Train Components with Implicit Filtering AU - Choi, T D AU - Eslinger, O J AU - Kelley, C T AU - David, J W AU - Etheridge, M A3 - North Carolina State University, Center for Research in Scientific Computation DA - 1998/12// PY - 1998/12// VL - 1 SP - 9-28 PB - North Carolina State University, Center for Research in Scientific Computation ER - TY - JOUR TI - Relative perturbation results for matrix eigenvalues and singular values AU - Ipsen, Ilse C. F. T2 - Acta Numerica AB - It used to be good enough to bound absolute of matrix eigenvalues and singular values. Not any more. Now it is fashionable to bound relative errors. We present a collection of relative perturbation results which have emerged during the past ten years. No need to throw away all those absolute error bound, though. Deep down, the derivation of many relative bounds can be based on absolute bounds. This means that relative bounds are not always better. They may just be better sometimes – and exactly when depends on the perturbation. DA - 1998/1// PY - 1998/1// DO - 10.1017/s0962492900002828 VL - 7 SP - 151-201 J2 - Acta Numerica LA - en OP - SN - 0962-4929 1474-0508 UR - http://dx.doi.org/10.1017/s0962492900002828 DB - Crossref ER - TY - JOUR TI - Hysteresis Modeling in Magnetostrictive Materials Via Preisach Operators AU - Smith, R.C. T2 - Journal of Mathematical Systems, Estimation and Control DA - 1998/// PY - 1998/// VL - 8 IS - 2 ER - TY - JOUR TI - The genetic algorithm optimization toolbox (GAOT) for Matlab 5 AU - Houck, CR T2 - http://www. ie. ncsu. edu/mirage/GAToolBox/gaot DA - 1998/// PY - 1998/// ER - TY - JOUR TI - Cell Formation Using Genetic Algorithms AU - Joines, J. A. AU - King, R. E. AU - Culbreth, C. T. T2 - Group Technology and Cellular Manufacturing DA - 1998/// PY - 1998/// DO - 10.1007/978-1-4615-5467-7_11 SP - 185-204 ER - TY - JOUR TI - The connectivity of acyclic orientation graphs AU - Savage, CD AU - Zhang, CQ T2 - DISCRETE MATHEMATICS AB - The acyclic orientation graph, AO(G), of an undirected graph, G, is the graph whose vertices are the acyclic orientations of G and whose edges are the pairs of orientations differing only by the reversal of one edge. Edelman (1984) has observed that it follows from results on polytopes that when G is simple, the connectivity of AO(G) is at least n − c, where n is the number of vertices and c is the number of components of G. In this paper we give a simple graph-theoretic proof of this fact. Our proof uses a result of independent interest. We establish that if H is a triangle-free graph with minimum degree at least k, and the graph obtained by contracting the edges of a matching in H is k-connected, then H is k-connected. The connectivity bound on AO(G) is tight for various graphs including Kn, Kp,q, and trees. Applications and extensions are discussed, as well as the connection with polytopes. DA - 1998/4/6/ PY - 1998/4/6/ DO - 10.1016/S0012-365X(97)00201-X VL - 184 IS - 1-3 SP - 281-287 SN - 0012-365X ER - TY - JOUR TI - Durfee polynomials AU - Canfield, E. R. AU - Corteel, S. AU - Savage, C. D. T2 - Electronic Journal of Combinatorics DA - 1998/// PY - 1998/// VL - 5 IS - 1, Research paper 32 SP - 1-21 ER - TY - JOUR TI - Call admission control schemes and ATM network topological design AU - Lo, SZ AU - Makrucki, BA AU - Bilbro, GL AU - Elmaghraby, SE T2 - EUROPEAN JOURNAL OF OPERATIONAL RESEARCH AB - Call admission control criteria are not only important for call admission control itself, but also can be an important input to network topological design. In this paper, we show the difference in terms of network cost incurred by adopting different call admission control schemes in network topological design. We compare two call admission control schemes. Scheme 1 uses equivalent bandwidth as its call admission control criterion and Scheme 2 is based on modeling the volatility of call traffic using Reflected Brownian Motion. Though Scheme 2 increases the complexity of network topological design, it can give lower network costs. Our experimental results show that for the same traffic mix, the network cost can be as little as 10% and as much as 35% lower when Scheme 2 is used instead of Scheme 1. The differences between the pair of resulting networks suggests that network topological design can be used as one of the criteria for choosing the call admission control scheme. DA - 1998/12/1/ PY - 1998/12/1/ DO - 10.1016/S0377-2217(97)00320-2 VL - 111 IS - 2 SP - 393-404 SN - 0377-2217 KW - ATM network topological design KW - call admission control KW - integer programming KW - mixed integer programming ER - TY - CHAP TI - Observer design for linear time varying descriptor systems: Numerical algorithms AU - Biehn, N. AU - Campbell, Stephen AU - Delebecque, F. AU - Nikoukhah, R. T2 - Proceedings of the 37th IEEE Conference on Decision and Control: December 16-18, 1998, Hyatt Regency Westshore, Tampa, Florida AB - Examines the design of observers for linear time varying descriptor systems for which the observer estimates are also physically correct in that they satisfy the same constraints as the solutions of the descriptor system. Careful attention is paid to ensuring that all quantities are computable by numerical algorithms. One way to implement this approach is fully developed. A computational example is given. CN - TJ217 .I17 1998 PY - 1998/// DO - 10.1109/cdc.1998.761815 SP - 3801–3806 PB - Piscataway, N.J.: IEEE ER - TY - CHAP TI - Intelligent DAE solvers and user friendly design, simulation, and analysis packages AU - Campbell, Stephen T2 - 1998 IEEE International Conference on Systems, Man, and Cybernetics: Intelligent systems for humans in a cyberworld, Hyatt La Jolla, San Diego, California, USA, October 11-14, 1998 AB - Simulation and design packages are an integral part of many computational systems. However, the current capabilities of many of these systems are limited by their ability to handle naturally posed questions in a user friendly manner. This paper examines what would be required to handle those problems that naturally lead to differential algebraic equations. CN - TA168 .I524 1998 PY - 1998/// DO - 10.1109/icsmc.1998.726491 SP - 177–3182 PB - Piscataway, NJ: IEEE ER - TY - CONF TI - Least squares estimation of nonhomogeneous Poisson processes AU - Kuhl, M. E. AU - Damerdji, H. AU - Wilson, J. R. AB - We formulate and evaluate weighted least squares (WLS) and ordinary least squares (OLS) procedures for estimating the parametric mean-value function of a nonhomogeneous Poisson process. We focus the development on processes having an exponential rate function, where the exponent may include a polynomial component or some trigonometric components. Unanticipated problems with the WLS procedure are explained by an analysis of the associated residuals. The OLS procedure is based on a square root transformation of the detrended event (arrival) times - that is, the fitted mean-value function evaluated at the observed event times; and under appropriate conditions, the corresponding residuals are proved to converge weakly to a normal distribution with mean 0 and variance 0.25. The results of a Monte Carlo study indicate the advantages of the OLS procedure with respect to estimation accuracy and computational efficiency. C2 - 1998/// C3 - 1998 Winter Simulation Conference: Proceedings: Grand Hotel, Washington, D.C., 13-16 December, 1998 CN - QA76.9.C65 W56 1998 DA - 1998/// DO - 10.1109/wsc.1998.745045 SP - 637-646 PB - Piscataway, New Jersey: IEEE ; New York, New York: Association for Computing Machinery ; San Diego, California: Society for Computer Simulation International ER - TY - CONF TI - A revised simplex search procedure for stochastic simulation response-surface optimization AU - Humphrey, D. G. AU - Wilson, J. R. AB - We develop a variant of the Nelder-Mead (NM) simplex search procedure for stochastic simulation optimization that is designed to avoid many of the weaknesses encumbering such direct-search methods-in particular, excessive sensitivity to starting values, premature termination at a local optimum, lack of robustness against noisy responses, and lack of computational efficiency. The revised simplex search (RSS) procedure consists of a three-phase application of the NM method in which: (a) the ending values for one phase become the starting values for the next phase; (b) the size of the initial simplex (respectively, the shrink coefficient) decreases geometrically (respectively, increases linearly) over successive phases; and (c) the final estimated optimum is the best of the ending values for the three phases. To compare RSS versus the NM procedure and RS9 (a simplex search procedure recently proposed by Barton and Ivey (1996)), we summarize a simulation study based on separate factorial experiments and follow-up multiple comparisons tests for four selected performance measures computed on each of six test problems, with three levels of problem dimensionality and noise variability used in each problem. The experimental results provide substantial evidence of RSS's improved performance with only marginally higher computational effort. C2 - 1998/// C3 - 1998 Winter Simulation Conference: Proceedings: Grand Hotel, Washington, D.C., 13-16 December, 1998 CN - QA76.9.C65 W56 1998 DA - 1998/// DO - 10.1109/wsc.1998.745060 SP - 751-760 PB - Piscataway, New Jersey: IEEE ; New York, New York: Association for Computing Machinery ; San Diego, California: Society for Computer Simulation International ER - TY - JOUR TI - Prediction of yarn tensile properties based on HVI testing of 36 U.S. upland cottons AU - Suh, M. W. AU - Koo, H.-J. AU - Cui, X. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 1 IS - 1998 SP - 786-790 ER - TY - CONF TI - Prototype decision support tool for developing tropospheric ozone control strategies AU - Loughlin, D. AU - Ranjithan, S. AU - Brill, E. D. AU - Baugh, J. AU - Fine, S. C2 - 1998/// C3 - Water resources and the urban environment-98: Proceedings of the 1998 National Conference on Environmental Engineering. ASCE Joint 25th Annual Conference on Water Resources Planning and Management and 1998 National Conference on Environmental Engineering, Chicago, IL, June 7-10,1998 CN - TD201 .N28 1998 DA - 1998/// PB - Reston, VA: American Society of Civil Engineers ER - TY - JOUR TI - Estimation of HVI bundle modulus and toughness as determinants to tensile properties of spun yarns AU - Suh, M. W. AU - Koo, H.-J. AU - Watson, M. D. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 2 IS - 1998 SP - 1530-1536 ER - TY - CONF TI - Development of alternative solid waste management options with economic and environmental considerations: A mathematical modeling approach AU - Ranjithan, S. R AU - Barlaz, M. A. AU - Brill, E. D. AU - Dumas, R. D. AU - Harrison, K. W. AU - Kosmicki, B. A. AU - Solano, E. C2 - 1998/// C3 - International Solid Waste Association 1998 World Congress, Charlotte, NC, Oct. 26-29, 1998 DA - 1998/// M1 - 1998 Oct. ER - TY - JOUR TI - Correlation-induction techniques for estimating quantiles in simulation experiments AU - Avramidis, AN AU - Wilson, , JR T2 - OPERATIONS RESEARCH AB - A simulation-based quantile estimator measures the level of system performance that can be delivered with a prespecified probability. To estimate selected quantiles of the response of a finite-horizon simulation, we develop procedures based on correlation induction techniques for variance reduction, with emphasis on antithetic variates and Latin hypercube sampling. These procedures achieve improved precision by controlling the simulation's random-number inputs as an integral part of the experimental design. The proposed multiple-sample quantile estimator is the average of negatively correlated quantile estimators computed from disjoint samples of the simulation response, where negative correlation is induced between corresponding responses in different samples while mutual independence of responses is maintained within each sample. The proposed single-sample quantile estimator is computed from negatively correlated simulation responses within one all-inclusive sample. The single-sample estimator based on Latin hypercube sampling is shown to be asymptotically normal and unbiased with smaller variance than the comparable direct-simulation estimator based on independent replications. Similar asymptotic comparisons of the multiple-sample and direct-simulation estimators focus on bias and mean square error. Monte Carlo results suggest that the proposed procedures can yield significant reductions in bias, variance, and mean square error when estimating quantiles of the completion time of a stochastic activity network. DA - 1998/// PY - 1998/// DO - 10.1287/opre.46.4.574 VL - 46 IS - 4 SP - 574-591 SN - 0030-364X ER - TY - JOUR TI - Quantitative management techniques and application in Taiwan AU - Fang, S. C. AU - Kao, C. T2 - International Journal of Operations and Quantitative Management DA - 1998/// PY - 1998/// VL - 4 IS - 3 ER - TY - CONF TI - Operation scheduling of mill/turn machining centers with genetic algorithms AU - Fang, S.-C. AU - Chiu, N. C. AU - Lee, Y. S. C2 - 1998/// C3 - Proceedings of the Fourth Joint Conference of Information Sciences. 1998 DA - 1998/// VL - 2 SP - 437-440 M1 - 1998 ER - TY - CONF TI - Multi-customer due-date bargaining with soft computing AU - Fang, S.-C. AU - Donovan, M. AU - Nuttle, H. AU - Wilson, J. C2 - 1998/// C3 - Proceedings of the Fourth Joint Conference of Information Sciences. 1998 DA - 1998/// VL - 2 SP - 84-87 M1 - 1998 ER - TY - JOUR TI - Inexact Newton methods and the method of lines for solving Richards' equation in two space dimensions AU - Tocci, MD AU - Kelley, CT AU - Miller, CT AU - Kees, CE T2 - COMPUTATIONAL GEOSCIENCES DA - 1998/// PY - 1998/// DO - 10.1023/A:1011562522244 VL - 2 IS - 4 SP - 291-309 SN - 1420-0597 KW - Richards' equation KW - method of lines KW - inexact Newton methods ER - TY - CHAP TI - Design and verification of real-time systems AU - Baugh, J. W. T2 - Artificial intelligence in structural engineering: Information technology for design, collaboration, maintenance, and monitoring AB - Advances in sensing, effecting, and computational technologies will change the way we design, construct, and monitor systems that interact with the physical world. Building structures will sense and respond to external loads, autonomous robots will occupy construction sites, and intelligent vehicles will monitor network flows to circumvent delays. As engineers, we must be prepared to work with the information technologies that underpin these coming systems. This paper addresses several of the prominent technical concerns in designing real-time systems that control some aspect of their environment. The view taken is that, by considering software systems to be an engineering artifact, we can begin to develop the kinds of quantitative approaches found in other areas of engineering design. CN - TA636 .A77 1998 PY - 1998/// DO - 10.1007/bfb0030441 VL - 1454 SP - 30-47 PB - Berlin; New York: Springer SN - 3540648062 ER - TY - CONF TI - A Web-based computing environment for structural analysis and design AU - Baugh, J. W., Jr. C2 - 1998/// C3 - Structural engineering world wide 1998: Proceedings of the Structural Engineers World Congress, July 19-23, 1998, San Francisco, California CN - TA633 .S88 1998 DA - 1998/// VL - 1 SP - T140-1 ER - TY - JOUR TI - The Winter Simulation Conference: The premier forum on simulation practice and theory AU - Wilson, J. R. AU - Carson, J. S. AU - Manivannan, M. T2 - OR/MS Today DA - 1998/// PY - 1998/// VL - 25 IS - 4 SP - 29-31 ER - TY - JOUR TI - Mixed symbolic-numerical computations with general DAEs II: An applications case study AU - Campbell, Stephen L. AU - Marszalek, W. T2 - Numerical Algorithms DA - 1998/// PY - 1998/// DO - 10.1023/A:1019106507166 VL - 19 IS - 1-4 SP - 85–94 SN - 1017-1398 KW - differential-algebraic equations KW - DAE KW - numerical integration KW - implicit differential equation ER - TY - JOUR TI - Mixed symbolic-numerical computations with general DAEs I: System properties AU - Campbell, Stephen L. AU - Hollenbeck, R. AU - Yeomans, K. AU - Zhong, Y. T2 - Numerical Algorithms DA - 1998/// PY - 1998/// DO - 10.1023/A:1019154423096 VL - 19 IS - 1-4 SP - 73–83 SN - 1017-1398 KW - differential-algebraic equations KW - DAE KW - numerical integration KW - implicit differential equation ER - TY - CHAP TI - The interaction between simulation and modeling in infinite dimensional systems AU - Campbell, Stephen AU - Marszalek, W. T2 - Theory and practice of control: proceedings of the 6th IEEE Mediterranean Conference, Alghero, Sardinia, Italy 9-11 June 1998 A2 - A. Tornambae, G. Conte A2 - Perdon, A. M. CN - TJ212 .T47 1998 PY - 1998/// DO - 10.1142/9789814447317_0053 SP - 322–327 PB - Singapore; River Edge, NJ: World Scientific ER - TY - JOUR TI - LQR control of thin shell dynamics: Formulation and numerical implementation AU - Del Rosario, RCH AU - Smith, RC T2 - JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES AB - A PDE-based feedback control method for thin cylindrical shells with surface-mounted piezoceramic actuators is presented. Donnell-Mushtari equations modified to incorporate both passive and active piezoceramic patch contributions are used to model the system dynamics. The well-posedness of this model and the associated LQR problem with an unbounded input operator are established through analytic semigroup theory. The model is discretized using a Galerkin expansion and basis functions constructed from Fourier polynomials tensored with cubic splines, and convergence criteria for the associated approximate LQR problem are established. The effectiveness of the method for attenuating the coupled longitudinal, circumferential and transverse shell displacements is illustrated through a set of numerical examples. DA - 1998/4// PY - 1998/4// DO - 10.1177/1045389X9800900408 VL - 9 IS - 4 SP - 301-320 SN - 1045-389X ER - TY - JOUR TI - Design of economical noise array experiments for a partially controlled simulation environment AU - Koksal, G. AU - Fathi, Yahya T2 - Computers & Industrial Engineering AB - Design of economical experiments for estimation of a response function's moments in a partially controlled laboratory environment is studied. The noise factors affecting the response are assumed to be statistically independent and normally distributed. It is also assumed that if a factor is set to a specific level in the experimentation, its actual value is also a normally distributed random variable with a smaller variance. Experimental design levels of the factors are found by matching first few moments of the response function calculated from the distributions of the factors, with the moments of that calculated from the distributions of the experimental values of the factors. These levels are evaluated with regard to the performance of appropriate moment estimators of the response. Suggestions are made as to which levels and experimental design should be used for different degrees of control in the experimentation environment. DA - 1998/// PY - 1998/// DO - 10.1016/S0360-8352(98)00157-0 VL - 35 IS - 3-4 SP - 555–558 ER - TY - JOUR TI - A global-filtering algorithm for linear programming problems with stochastic elements AU - Guan, SH AU - Fang, SC T2 - MATHEMATICAL METHODS OF OPERATIONS RESEARCH DA - 1998/// PY - 1998/// DO - 10.1007/s001860050029 VL - 48 IS - 3 SP - 287-316 SN - 1432-2994 KW - linear programming KW - stochastic programming KW - Kalman filter KW - infeasible-interior-point method ER - TY - BOOK TI - Probability and random processes for electrical engineers AU - Viniotis, Y. CN - QA273 .V55 1998 DA - 1998/// PY - 1998/// PB - Boston, MA: WCB/McGraw-Hill SN - 0070674914 ER - TY - CHAP TI - On second order sufficient conditions for structured nonlinear programs in infinite-dimensional function spaces AU - Dunn, J. C. T2 - Mathematical programming with data perturbations CN - QA402.5 .M3558 1998 PY - 1998/// SP - 83-108 PB - New York: Marcel Dekker ER - TY - JOUR TI - Solving convex programming problems with equality constraints by neural networks AU - Chen, YH AU - Fang, SC T2 - COMPUTERS & MATHEMATICS WITH APPLICATIONS AB - This paper presents a neural network approach for solving convex programming problems with equality constraints. After defining the energy function and neural dynamics of the proposed neural network, we show the existence of an equilibrium point at which the neural dynamics becomes asymptotically stable. It is shown that under proper conditions, an optimal solution of the underlying convex programming problems is an equilibrium point of the neural dynamics, and vise versa. The configuration of the proposed neural network with an exact layout is provided for solving linear programming problems. The operational characteristics of the neural network are demonstrated by numerical examples. DA - 1998/10// PY - 1998/10// DO - 10.1016/S0898-1221(98)00172-2 VL - 36 IS - 7 SP - 41-68 SN - 0898-1221 KW - convex programming KW - penalty function KW - artificial neural networks KW - Hopfield networks ER - TY - JOUR TI - Relative perturbation results for eigenvalues and eigenvectors of diagonalisable matrices AU - Eisenstat, SC AU - Ipsen, ICF T2 - BIT AB - Let $$\hat \lambda $$ and $$\hat x$$ be a perturbed eigenpair of a diagonalisable matrixA. The problem is to bound the error in $$\hat \lambda $$ and $$\hat \lambda $$ . We present one absolute perturbation bound and two relative perturbation bounds. The absolute perturbation bound is an extension of Davis and Kahan's sin θ Theorem from Hermitian to diagonalisable matrices. The two relative perturbation bounds assume that $$\hat \lambda $$ and $$\hat x$$ are an exact eigenpair of a perturbed matrixD 1 AD 2 , whereD 1 andD 2 are non-singular, butD 1 AD 2 is not necessarily diagonalisable. We derive a bound on the relative error in $$\hat \lambda $$ and a sin θ theorem based on a relative eigenvalue separation. The perturbation bounds contain both the deviation ofD 1 andD 2 from similarity and the deviation ofD 2 from identity. DA - 1998/9// PY - 1998/9// DO - 10.1007/BF02510256 VL - 38 IS - 3 SP - 502-509 SN - 0006-3835 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0039285620&partnerID=MN8TOARS KW - eigenvalue KW - eigenvector KW - condition number KW - relative error KW - diagonalisable matrix KW - angle between subspaces ER - TY - JOUR TI - Graphical basis partitions AU - Nolan, JM AU - Sivaraman, V AU - Savage, CD AU - Tiwari, PK T2 - GRAPHS AND COMBINATORICS AB - A partition of an integer n is graphical if it is the degree sequence of a simple, undirected graph. It is an open question whether the fraction of partitions of n which are graphical approaches 0 as n approaches infinity. A partition π is basic if the number of dots in its Ferrers graph is minimum among all partitions with the same rank vector as π. In this paper, we investigate graphical partitions via basis partitions. We show how to efficiently count and generate graphical basis partitions and how to use them to count graphical partitions. We give empirical evidence which leads us to conjecture that, as n approaches infinity, the fraction of basis partitions of n which are graphical approaches the same limit as the fraction of all partitions of n which are graphical. DA - 1998/// PY - 1998/// DO - 10.1007/s003730050029 VL - 14 IS - 3 SP - 241-261 SN - 0911-0119 ER - TY - JOUR TI - Speaker independence in automated lip-sync for audio-video communication AU - McAllister, DF AU - Rodman, RD AU - Bitzer, DL AU - Freeman, AS T2 - COMPUTER NETWORKS AND ISDN SYSTEMS AB - By analyzing the absolute value of the Fourier transform of a speaker's voice signal we can predict the position of the mouth for English vowel sounds. This is without the use of text, speech recognition or mechanical or other sensing devices attached to the speaker's mouth. This capability can reduce the time required for mouth animation considerably. We expect it to be competitive eventually with the speech/text driven solutions which are becoming popular. Our technique would require much less interaction from the user and no knowledge of phonetic spelling. We discuss the problems of producing an algorithm that is speaker independent. The goal is to avoid having to measure mouth movements off video for each speaker's training sounds. We have discovered that eliminating variation due to pitch yields moments which are mouth shape dependent but not speaker dependent. This implies that careful construction of predictor surfaces can produce speaker independent prediction of mouth motion for English vowels. DA - 1998/11/12/ PY - 1998/11/12/ DO - 10.1016/S0169-7552(98)00216-5 VL - 30 IS - 20-21 SP - 1975-1980 SN - 0169-7552 KW - facial animation KW - lip synchronization KW - speech processing ER - TY - JOUR TI - Semantical considerations on intention dynamics for BDI agents AU - Singh, MP T2 - JOURNAL OF EXPERIMENTAL & THEORETICAL ARTIFICIAL INTELLIGENCE AB - The BDI paradigm is a powerful means for constructing intelligent agents in terms of their beliefs, desires, and intentions. For this paradigm to bear its full potential, it must incorporate considerations from rationality. This paper develops a set of postulates for intelligent agents who deliberate about their intentions and actions. However, even simple postulates can lead to paradoxical results when formalized naively. We propose an approach based on temporal possibility and action that avoids those problems. This approach incorporates a formal model based on branching time in which a probabilistic analysis of choice can be captured. In this manner, the intuitions of the BDI paradigm can be reconciled with those of rational agency. DA - 1998/// PY - 1998/// DO - 10.1080/095281398146752 VL - 10 IS - 4 SP - 551-564 SN - 0952-813X UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032344134&partnerID=MN8TOARS KW - intentions KW - rational agents KW - BDI model KW - BDI architectures ER - TY - JOUR TI - Relaxed cutting plane method for solving linear semi-infinite programming problems AU - Wu, S. Y. AU - Fang, Shu-Cherng AU - Lin, C. J. T2 - Journal of Optimization Theory and Applications AB - One of the major computational tasks of using the traditional cutting plane approach to solve linear semi-infinite programming problems lies in finding a global optimizer of a nonlinear and nonconvex program. This paper generalizes the Gustafson and Kortanek scheme to relax this requirement. In each iteration, the proposed method chooses a point at which the infinite constraints are violated to a degree, rather than a point at which the violations are maximized. A convergence proof of the proposed scheme is provided. Some computational results are included. An explicit algorithm which allows the unnecessary constraints to be dropped in each iteration is also introduced to reduce the size of computed programs. DA - 1998/// PY - 1998/// DO - 10.1023/A:1021763419562 VL - 99 IS - 3 SP - 759–779 ER - TY - JOUR TI - Optimal cutter selection and machining plane determination for process planning and NC machining of complex surfaces AU - Chen, YH AU - Lee, YS AU - Fang, SC T2 - JOURNAL OF MANUFACTURING SYSTEMS AB - This paper deals with the optimal cutter selection and machining plane determination problems for NC machining and process planning. Two optimization methods, an integer programming (IP) method and a dynamic programming (DP) method, are presented. While the IP method provides an upper bound for such a problem, the DP method provides an optimal solution at the cost of longer computational time. Both methods can be used to automate the traditional, experience-based cutter selection tasks and to reduce the total machining time in NC machining operations. Numerical examples are included to illustrate both methods. DA - 1998/// PY - 1998/// DO - 10.1016/S0278-6125(98)80004-6 VL - 17 IS - 5 SP - 371-388 SN - 0278-6125 KW - cutter selection KW - process planning KW - computer aided manufacturing KW - NC machining KW - dynamic programming KW - integer programming ER - TY - JOUR TI - On the mean waiting time of a population constrained open tandem queueing network with constant service times AU - Rhee, Y. AU - Perros, H. G. T2 - IIE Transactions AB - We obtain an approximate expression for the mean waiting time of an open tandem queueing network with population constraint, constant service times and an arbitrary arrival process. DA - 1998/// PY - 1998/// DO - 10.1080/07408179808966550 VL - 30 IS - 10 SP - 973-979 ER - TY - CONF TI - Automated lip-sync animation as a telecommunications aid for the hearing impaired AU - Rodman, R. D. AU - McAllister, D. F. AU - Bitzer, D. L. AU - Freeman, A. S. C2 - 1998/// C3 - Proceedings, 1998 IEEE 4th Workshop Interactive Voice Technology for Telecommunications Applications: IVTTA '98, September 29th-30th, 1998, Turino, Italy CN - TK7882.S65 I39 1998 DA - 1998/// SP - 202-208 PB - New York: Institute of Electrical and Electronics Engineers, Inc.; Piscataway, NJ: IEEE Service Center ER - TY - JOUR TI - Applying the mu-calculus in planning and reasoning about action AU - Singh, MP T2 - JOURNAL OF LOGIC AND COMPUTATION AB - Planning algorithms have traditionally been geared towards achievement goals in single-agent environments. Such algorithms essentially produce plans to reach one of a specified set of states. More general approaches for planning based on temporal logic (TL) are emerging. Current approaches tend to use linear TL, and can handle sets of sequences of states. However, they assume deterministic actions with all changes effected solely by one agent. By contrast, we use a branching model of time that can express concurrent actions by multiple agents and the environment, leading to nondeterministic effects of an agent's actions. For this reason, we view plans not as sequences of actions, but as decision graphs describing the agent's actions in different situations. Thus, although we consider single-agent decision graphs, our approach is better suited to multiagent systems. We also consider an expressive formalism, which allows a wider variety of goals, including achievement and maintenance goals. Achievement corresponds to traditional planning, but maintenance is more powerful than traditional maintenance goals, and may require nonterminating plans. To formalize decision graphs requires a means to ‘alternate’ the agent's and the environment's choices. From logics of program, we introduce the prepositional mu-calculus;, which has operators for least and greatest fixpoints. We give a semantics, a fixpoint characterization, and an algorithm to compute decision graphs. DA - 1998/6// PY - 1998/6// DO - 10.1093/logcom/8.3.425 VL - 8 IS - 3 SP - 425-445 SN - 1465-363X UR - https://publons.com/publon/21294536/ KW - mu-calculus KW - planning KW - reasoning about action KW - temporal logic ER - TY - CONF TI - A customizable coordination service for autonomous agents AU - Singh, M. P. A2 - M. P. Singh, A. Rao A2 - Wooldridge, M. J. C2 - 1998/// C3 - Intelligent agents IV: Agent theories, architectures, and languages: 4th International Workshop, ATAL'97, Providence, Rhode Island, USA, July 24-26, 1997: Proceedings CN - QA76.76.I58 A83 1997 DA - 1998/// SP - 93-106 PB - New York: Springer ER - TY - JOUR TI - A bijection for partitions with all ranks at least t AU - Corteel, S AU - Savage, CD AU - Venkatraman, R T2 - JOURNAL OF COMBINATORIAL THEORY SERIES A AB - It follows from the work of Andrews and Bressoud that fort⩽1, the number of partitions ofnwith all successive ranks at leasttis equal to the number of partitions ofnwith no part of size 2−t. We give a simple bijection for this identity which generalizes a result of Cheema and Gordon for 2-rowed plane partitions. The bijection yields several refinements of the identity when the partition counts are parametrized by the number of parts and/or the size of the Durfee rectangle. In addition, it gives an interpretation of the difference of (shifted) successive Gaussian polynomials which we relate to other interpretations of Andrews and Fishel. DA - 1998/8// PY - 1998/8// DO - 10.1006/jcta.1998.2873 VL - 83 IS - 2 SP - 202-220 SN - 0097-3165 ER - TY - JOUR TI - Real-time optical characterization of GaP heterostructures by p-polarized reflectance AU - Dietz, N AU - Ito, K T2 - THIN SOLID FILMS AB - The stringent tolerances in the engineering of advanced optoelectronic integrated circuits with respect to control thickness and composition of ultra-thin layers require the development of monitoring and control techniques that follow the deposition process with sub-monolayer resolution. These demands led to the development of surface-sensitive real-time optical sensors that are able to move the control point close to the point where the growth occurs, which in a chemical beam epitaxy process is the surface reaction layer, built up of physisorbed and chemisorbed precursor fragments between the ambient and film interface. In this contribution, we explore the application of p-polarized reflectance spectroscopy (PRS) in the context of real-time monitoring and control of pulsed chemical beam epitaxy (PCBE) during low temperature growth of epitaxial GaP heterostructures on Si(001) substrates by PCBE. The effect of periodic alterations in composition and thickness of a surface reaction layer (SRL) is monitored by PRS as a periodic modulated reflectance amplitude, denoted as fine structure. Using a `reduced order kinetic model' we demonstrate the linkage of the PRS response towards surface reaction chemistry, film growth rate, and film properties. Mathematical control algorithms are introduced that link the PR signals to the growth process control parameters. DA - 1998/2// PY - 1998/2// DO - 10.1016/S0040-6090(97)00896-1 VL - 313 SP - 614-619 SN - 0040-6090 KW - p-polarized reflectance spectroscopy KW - pulsed chemical beam epitaxy KW - reduced order kinetic model ER - TY - JOUR TI - Optimal control of thermally convected fluid flows AU - Ito, K AU - Ravindran, SS T2 - SIAM JOURNAL ON SCIENTIFIC COMPUTING AB - We examine the optimal control of stationary thermally convected fluid flows from the theoretical and numerical point of view. We use thermal convection as control mechanism; that is, control is effected through the temperature on part of the boundary. Control problems are formulated as constrained minimization problems. Existence of optimal control is given and a first-order necessary condition of optimality from which optimal solutions can be obtained is established. We develop numerical methods to solve the necessary condition of optimality and present computational results for control of cavity- and channel-type flows showing the feasibility of the proposed approach. DA - 1998/11// PY - 1998/11// DO - 10.1137/S1064827596299731 VL - 19 IS - 6 SP - 1847-1869 SN - 1064-8275 KW - flow control KW - temperature control KW - optimization KW - Navier-Stokes equations KW - finite element methods ER - TY - PCOMM TI - On locally invertible rate-1/n convolutional encoders AU - Bitzer, DL AU - Dholakia, A AU - Koorapaty, H AU - Vouk, MA AB - A locally invertible convolutional encoder has a local inverse defined as a full rank w/spl times/w matrix that specifies a one-to-one mapping between equal-length blocks of information and encoded bits. In this correspondence, it is shown that a rate-1/n convolutional encoder is nondegenerate and noncatastrophic if and only if it is locally invertible. Local invertibility is used to obtain upper and lower bounds on the number of consecutive zero-weight branches in a convolutional codeword. Further, existence of a local inverse can be used as an alternate test for noncatastrophicity instead of the usual approach involving computation of the greatest common divisor of n polynomials. DA - 1998/1// PY - 1998/1// DO - 10.1109/18.651074 SP - 420-422 KW - convolutional encoders KW - focally invertible encoders KW - noncatastrophic encoders KW - semi-infinite generator matrix KW - zero-run problem ER - TY - JOUR TI - Evaluation of AGV routeing strategies using hierarchical simulation AU - Seifert, RW AU - Kay, MG AU - Wilson, , JR T2 - INTERNATIONAL JOURNAL OF PRODUCTION RESEARCH AB - To analyse an automated guided vehicle (AGV) system operating under selected vehicle routeing strategies, we present a simulation model that can handle an arbitrary system layout as well as arbitrary numbers of AGVs and pedestrians causing congestion in the system. We introduce a dynamic vehicle routeing strategy based on hierarchical simulation that operates as follows: at the time of each AGV routeing decision in the main simulation, subordinate simulations are performed to evaluate a limited set of alternative routes in succession until the current routeing decision can be finalized and the main simulation resumed. A case study involving a prototype AGV system operating under the control of a global vision system illustrates the advantages not only of this strategy but also of global-vision-based control. DA - 1998/7// PY - 1998/7// DO - 10.1080/002075498193057 VL - 36 IS - 7 SP - 1961-1976 SN - 0020-7543 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032121916&partnerID=MN8TOARS ER - TY - JOUR TI - Three absolute perturbation bounds for matrix eigenvalues imply relative bounds AU - Eisenstat, SC AU - Ipsen, ICF T2 - SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS AB - We show that three well-known perturbation bounds for matrix eigenvalues imply relative bounds: the Bauer--Fike and Hoffman--Wielandt theorems for diagonalizable matrices, and Weyl's theorem for Hermitian matrices. As a consequence, relative perturbation bounds are not necessarily stronger than absolute bounds, and the conditioning of an eigenvalue in the relative sense is the same as in the absolute sense. We also show that eigenvalues of normal matrices are no more sensitive to perturbations than eigenvalues of Hermitian positive-definite matrices. The relative error bounds are invariant under congruence transformations, such as grading and scaling. DA - 1998/9/22/ PY - 1998/9/22/ DO - 10.1137/S0895479897323282 VL - 20 IS - 1 SP - 149-158 SN - 0895-4798 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032217351&partnerID=MN8TOARS KW - eigenvalues KW - relative perturbation bounds KW - conditioning ER - TY - JOUR TI - Theoretical and practical aspects of fiber length comparisons of various cottons AU - Cui, X. L. AU - Calamari, T. A. AU - Suh, M. W. T2 - Textile Research Journal AB - Fiber length is one of the most important physical properties of cotton. Frequently, it is necessary to compare the fiber lengths of various cottons. The commonly used statistical characteristics of a cotton fiber length distribution include the mean fiber length, short fiber content, and upper quartile length. These statistics may be calculated from number-based or weight-based distributions. This paper shows theoretically and experimentally that number-based and weight-based statistics may give opposite rank orders in some cases when they are used to compare cotton fiber lengths. DA - 1998/// PY - 1998/// DO - 10.1177/004051759806800701 VL - 68 IS - 7 SP - 467-472 ER - TY - JOUR TI - Robust solution of Richards' equation for nonuniform porous media AU - Miller, CT AU - Williams, GA AU - Kelley, CT AU - Tocci, MD T2 - WATER RESOURCES RESEARCH AB - Capillary pressure–saturation‐relative permeability relations described using the van Genuchten [1980] and Mualem [1976] models for nonuniform porous media lead to numerical convergence difficulties when used with Richards' equation for certain auxiliary conditions. These difficulties arise because of discontinuities in the derivative of specific moisture capacity and relative permeability as a function of capillary pressure. Convergence difficulties are illustrated using standard numerical approaches to simulate such problems. We investigate constitutive relations, interblock permeability, nonlinear algebraic system approximation methods, and two time integration approaches. An integral permeability approach approximated by Hermite polynomials is recommended and shown to be robust and economical for a set of test problems, which correspond to sand, loam, and clay loam media. DA - 1998/10// PY - 1998/10// DO - 10.1029/98WR01673 VL - 34 IS - 10 SP - 2599-2610 SN - 0043-1397 ER - TY - JOUR TI - Performance analysis of a photonic single-hop ATM switch architecture, with tunable transmitters and fixed frequency receivers AU - McKinnon, MW AU - Rouskas, GN AU - Perros, HG T2 - PERFORMANCE EVALUATION AB - We consider a photonic asynchronous transfer mode (ATM) switch based on the single-hop wavelength division multiplexing (WDM) architecture with tunable transmitters and fixed frequency receivers. The switch operates under a schedule that masks the transceiver tuning latency. We analyze approximately a queueing model of the switch in order to obtain the queue-length distribution and the cell-loss probability at the input and output ports. The analysis is carried out assuming two-state Markov modulated Bernoulli process (MMBP) sources that capture the notion of burstiness and correlation, two important characteristics of ATM traffic, and non-uniform destination probabilities. We present results which establish that the performance of the switch is a complex function of a number of system parameters, including the load balancing and scheduling algorithms, the number of available channels, and the buffer capacity. We also show that the behavior of the switch in terms of cell-loss probability as these parameters are varied cannot be predicted without an accurate analysis. Our work makes it possible to study the interactions among the system parameters, and to predict, explain, and fine tune the performance of the switch. DA - 1998/7// PY - 1998/7// DO - 10.1016/S0166-5316(98)00003-0 VL - 33 IS - 2 SP - 113-136 SN - 1872-745X KW - optical networks KW - photonic ATM switch architecture KW - Markov modulated Bernoulli process (MMBP) KW - wavelength division multiplexing (WDM) KW - discrete-time queueing networks ER - TY - JOUR TI - L-2 sufficient conditions for end-constrained optimal control problems with inputs in a polyhedron AU - Dunn, JC T2 - SIAM JOURNAL ON CONTROL AND OPTIMIZATION AB - An $\hbox{{\bbb L}}^2$-local optimality sufficiency theorem is proved for a class of structured infinite-dimensional nonconvex programs with constraints of the form $u\in\Omega$ and h(u)=0, where $\Omega$ is a set of Lebesgue measurable essentially bounded vector-valued functions $u(\cdot ): [0,1]\rightarrow \hbox{{\bbb R}}^m$ with range in a polyhedron U, and h is a smooth map of the space of essentially bounded functions $u(\cdot )$ into ${\bbb R}^k$. The sufficiency theorem is based on formal counterparts of the finite-dimensional Karush--Kuhn--Tucker sufficient conditions in a Cartesian product of polyhedra, a strengthened variant of Pontryagin's necessary condition, and structure and continuity conditions on the first and second differentials of the objective function and equality constraint functions. The new sufficient conditions are directly applicable to nonconvex continuous-time Bolza optimal control problems with control-quadratic Hamiltonians, unqualified affine inequality constraints on vector-valued control inputs, and equality constraints on the terminal state vector or equivalent isoperimetric constraints on integrals of functions depending on the state and control variables. DA - 1998/9// PY - 1998/9// DO - 10.1137/S0363012995288513 VL - 36 IS - 5 SP - 1833-1851 SN - 0363-0129 KW - infinite-dimensional programs KW - affine inequality constraints KW - nonconvex equality constraints KW - nonconvex objectives KW - L-2-local optimality KW - second-order sufficient conditions KW - optimal control KW - constrained inputs KW - terminal state constraints ER - TY - JOUR TI - Basis partitions AU - Nolan, JM AU - Savage, CD AU - Wilf, HS T2 - DISCRETE MATHEMATICS AB - We study basis partitions , introduced by Hansraj Gupta in 1978. For this family of partitions, we give a recurrence, a generating function, identities relating basis partitions to more familiar families of partitions, and a new characterization of basis partitions. DA - 1998/1/15/ PY - 1998/1/15/ DO - 10.1016/S0012-365X(97)00101-5 VL - 179 IS - 1-3 SP - 277-283 SN - 0012-365X ER - TY - CHAP TI - Augmented gradient projection calculations for regulator problems with pointwise state and control constraints AU - Dunn, J. C. T2 - Optimal control: Theory, algorithms, and applications A2 - W. W. Hager, A2 - Pardalos, P. M. AB - A new implementation of the augmented gradient projection (AGP) scheme is described for discrete-time approximations to continuous-time Bolza optimal control problems with pointwise bounds on control and state variables. In the conventional implementation, control and state vectors are the primal variables, and local forms of the control problem’s state equations are treated as equality constraints incorporated in an augmented Lagrangian with a penalty parameter c. In the new implementation, the original control vectors and new artificial control vectors are the primal variables, and an integrated form of the state equations replaces the usual local form in the augmented Lagrangian. The resulting relaxed nonlinear program for the augmented Lagrangian amounts to a Bolza problem with pure pointwise control constraints, hence the associated gradient and Newtonian direction vectors can be computed efficiently with adjoint equations and dynamic programming techniques. For unscaled AGP methods and prototype regulator problems with bound constraints on control and state vectors, numerical experiments indicate rapid deterioration in the convergence properties of the conventional implementation as the discrete-time mesh is refined with the penalty constant fixed. In contrast, the new implementation of the unscaled AGP scheme exhibits mesh-independent convergence behavior. The new formulation also offers certain additional computational advantages for control problems with separated control and state constraints. CN - QA402.3 .H27 1998 PY - 1998/// DO - 10.1007/978-1-4757-6095-8_7 SP - 130-153 PB - Boston: Kluwer Academic Pubs. ER - TY - JOUR TI - A fast iterative algorithm for elliptic interface problems AU - Li, ZL T2 - SIAM JOURNAL ON NUMERICAL ANALYSIS AB - A fast, second-order accurate iterative method is proposed for the elliptic equation \[ \grad\cdot(\beta(x,y) \grad u) =f(x,y) \] in a rectangularregion $\Omega$ in two-space dimensions. We assume that there is an irregular interface across which the coefficient $\beta$, the solution u and its derivatives, and/or the source term f may have jumps. We are especially interested in the cases where the coefficients $\beta$ are piecewise constant and the jump in $\beta$ is large. The interface may or may not align with an underlying Cartesian grid. The idea in our approach is to precondition the differential equation before applying the immersed interface method proposed by LeVeque and Li [ SIAM J. Numer. Anal., 4 (1994), pp. 1019--1044]. In order to take advantage of fast Poisson solvers on a rectangular region, an intermediate unknown function, the jump in the normal derivative across the interface, is introduced. Our discretization is equivalent to using a second-order difference scheme for a corresponding Poisson equation in the region, and a second-order discretization for a Neumann-like interface condition. Thus second-order accuracy is guaranteed. A GMRES iteration is employed to solve the Schur complement system derived from the discretization. A new weighted least squares method is also proposed to approximate interface quantities from a grid function. Numerical experiments are provided and analyzed. The number of iterations in solving the Schur complement system appears to be independent of both the jump in the coefficient and the mesh size. DA - 1998/2// PY - 1998/2// DO - 10.1137/S0036142995291329 VL - 35 IS - 1 SP - 230-254 SN - 1095-7170 KW - elliptic equation KW - discontinuous coefficients KW - immersed interface method KW - Cartesian grid KW - Schur complement KW - GMRES method KW - preconditioning ER - TY - JOUR TI - Toward a model theory of actions: How agents do it in branching time AU - Singh, MP T2 - COMPUTATIONAL INTELLIGENCE AB - A clear understanding and formalization of actions is essential to computing, and especially so to reasoning about and constructing intelligent agents. Several approaches have been proposed over the years. However, most approaches concentrate on the causes and effects of actions, but do not give general characterizations of actions themselves. A useful formalization of actions would be based on a general, possibly nondiscrete, model of time that allows branching (to capture agents’ choices). A desirable formalization would also allow actions to be of arbitrary duration and would permit multiple agents to act concurrently. We develop a branching‐time framework that allows great flexibility in how time and action are modeled. We motivate and formalize several coherence constraints on our models, which capture some nice intuitions and validate some useful inferences relating actions with time. DA - 1998/8// PY - 1998/8// DO - 10.1111/0824-7935.00064 VL - 14 IS - 3 SP - 287-317 SN - 0824-7935 UR - https://publons.com/publon/21294532/ KW - actions KW - time KW - formal models KW - branching-time temporal logics ER - TY - JOUR TI - Soil bulk density, soil strength, and regeneration of a bottomland hardwood site one year after harvest AU - Hassan, A. E. AU - Roise, Joseph T2 - Transactions of the ASAE AB - The first year soil physical properties and regeneration measurements following harvest indicate ampleregeneration on all treatments including the landing areas. Comparisons included three machine systems (three skidders)and a helicopter-yarded control that were field tested for harvesting a bottomland hardwood site under adverseconditions. The results also demonstrate a significantly greater number of tree stem count following the winter than thesummer harvest. Results of the statistical analysis of soil bulk density indicate that the soil had partially recovered frommachine traffic one year after harvest. DA - 1998/// PY - 1998/// DO - 10.13031/2013.17273 VL - 41 IS - 5 SP - 1501–1508 ER - TY - JOUR TI - Rank modifications of semidefinite matrices associated with a secant update formula AU - Chu, MT AU - Funderlic, RE AU - Golub, GH T2 - SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS AB - This paper analyzes rank modification of symmetric positive definite matrices H of the form H- M+ P, where H- M denotes a step of reducing H to a lower-rank, symmetric and positive semidefinite matrix and ( H- M)+ P denotes a step of restoring H- M to a symmetric positive definite matrix. These steps and their generalizations for rectangular matrices are fully characterized. The well-known BFGS and DFP updates used in Hessian and inverse Hessian approximations provided the motivation for the generalizations and are special cases with H and P having rank one. DA - 1998/10/30/ PY - 1998/10/30/ DO - 10.1137/S0895479896306021 VL - 20 IS - 2 SP - 428-436 SN - 0895-4798 KW - rank-one reduction KW - Wedderburn theorem KW - BFGS update KW - DFP update KW - quasi-Newton methods KW - rank subtractivity KW - rank additivity ER - TY - CONF TI - On L-2 sufficient conditions for end-constrained optimal control problems with inputs in a polyhedron AU - Dunn, J. C. AB - An L/sup 2/-local optimality sufficiency theorem proved for constrained optimal control problems is described here. This theorem applies to a class of structured infinite-dimensional nonconvex programs with constraints of the form, u/spl isin//spl Omega/ and h(u)=0, where /spl Omega/ is a set of Lebesgue measurable essentially bounded vector-valued functions u(/spl middot/):[0, 1]/spl rarr/R/sup m/ with range in a polyhedron U, and h is a smooth map of the space of essentially bounded functions u(/spl middot/) into R/sup k/. The theorem is based on formal counterparts of the finite-dimensional Karush-Kuhn-Tucker sufficient conditions in a Cartesian product of polyhedra, a strengthened variant of Pontryagin's necessary condition, and structure/continuity conditions on the first and second differentials of the objective function and equality constraint functions. Its sufficient conditions are directly applicable to nonconvex continuous-time Bolza optimal control problems with control-quadratic Hamiltonians, affine inequality constraints on the control inputs, and equality constraints on the terminal state vector, or equivalent isoperimetric constraints. C2 - 1998/// C3 - Proceedings of the 37th IEEE Conference on Decision and Control, Tampa, FL, December 16-18, 1998 CN - TJ217 .I17 1998 DA - 1998/// DO - 10.1109/cdc.1998.758679 ER - TY - BOOK TI - Cornelius Lanczos: Collected published papers with commentaries AU - Davis, W. R. AU - Chu, M. T. AU - McConnell, J. R. AU - Dolan, P. AU - Norris, L. K. AU - Ortiz, E. AU - Plemmon, R. J. AU - Ridgeway, D. AU - Scaife, B.K.P. AU - Stewart, W. J. AU - York, J. W. AU - Doggett, W. O. AU - Gellai, B. M. AU - Gsponer, A. A. AU - Prioli, C. A. CN - QC19.3 .L363 1998 DA - 1998/// PY - 1998/// PB - Raleigh, NC: College of Physical and Mathematical Sciences, North Carolina State University SN - 0929493003 ER - TY - JOUR TI - A dispersion model for the hepatic uptake and elimination of 2,3,7,8-tetrachlorodibenzo-p-dioxin AU - Banks, HT AU - Musante, CJ AU - Tran, HT T2 - MATHEMATICAL AND COMPUTER MODELLING AB - A convection-dispersion model for the uptake and elimination of 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD) in the liver is presented. The model is adapted from the general dispersion model of Roberts and Rowland and includes the dynamics of TCDD interaction with two intracellular proteins, the Ah receptor and cytochrome P450 IA2. A “well-mixed” compartment was added to describe the venous blood concentration of TCDD. The result is a nonlinear system of seven coupled partial and ordinary differential equations with time delays. DA - 1998/7// PY - 1998/7// DO - 10.1016/S0895-7177(98)00077-6 VL - 28 IS - 1 SP - 9-29 SN - 0895-7177 KW - physiologically-based pharmacokinetic (PBPK) model KW - 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) KW - liver transport models KW - nonlinear partial differential equations KW - delay equations ER - TY - JOUR TI - A case study in off-line quality control: characterization and optimization of batch dyeing process design AU - Koksal, G AU - Smith, WA AU - Fathi, Y AU - Lu, JCY AU - McGregor, R T2 - INTERNATIONAL JOURNAL OF TECHNOLOGY MANAGEMENT AB - A method is provided and demonstrated for robust design of the batch dyeing process. This method is used to identify optimal batch dyeing process parameter settings, which produce target colour with the least colour variation within and among dyed fabric pieces. The robust design problem is defined in terms of the design objectives, control factors and noise factors. Performance measures are presented to evaluate mean and dispersion characteristics of the dyeing output. Design and conduct of experiments are discussed for developing empirical models of the performance measures, and these models are developed for the study case. The robust design problem is formulated and solved as a nonlinear programming problem. Confirmation of results and iterative use of the proposed design method are discussed. DA - 1998/// PY - 1998/// DO - 10.1504/IJTM.1998.002676 VL - 16 IS - 4-6 SP - 358-382 SN - 0267-5730 KW - off-line quality control KW - quality engineering KW - parameter design KW - robust design KW - design optimization KW - textiles dyeing KW - colour control ER - TY - JOUR TI - Viscous scalar conservation law with nonlinear flux feedback and global attractors AU - Ito, K AU - Yan, Y T2 - JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS AB - In this paper we study the forced viscous scalar conservation law on (0, 1) with the nonlinear flux feedback at the boundary. Global existence and uniqueness are established forL∞bounded initial conditions and forcing functions. Under an appropriate growth condition on the flux function and nonlinear dissipation at the boundary, we show the existence of an absorbing set that absorbs the whole spaceL∞(0, 1), and the existence of a compact global attractor in theL∞topology. DA - 1998/11/1/ PY - 1998/11/1/ DO - 10.1006/jmaa.1998.6016 VL - 227 IS - 1 SP - 271-299 SN - 0022-247X KW - viscous scalar conservation law KW - nonlinear boundary feedback KW - L-infinity estimates KW - absorbing sets KW - global attractors ER - TY - JOUR TI - An unconstrained convex programming approach to linear semi-infinite programming AU - Lin, CJ AU - Fang, SC AU - Wu, SY T2 - SIAM JOURNAL ON OPTIMIZATION AB - In this paper, an unconstrained convex programming dual approach for solving a class of linear semi-infinite programming problems is proposed. Both primal and dual convergence results are established under some basic assumptions. Numerical examples are also included to illustrate this approach. DA - 1998/5// PY - 1998/5// DO - 10.1137/S105262349427621X VL - 8 IS - 2 SP - 443-456 SN - 1095-7189 KW - semi-infinite programming KW - linear programming KW - convex programming KW - entropy optimization ER - TY - JOUR TI - A pentagonal number sieve AU - Corteel, S AU - Savage, CD AU - Wilf, HS AU - Zeilberger, D T2 - JOURNAL OF COMBINATORIAL THEORY SERIES A AB - We prove a general “pentagonal sieve” theorem that has corollaries such as the following. First, the number of pairs of partitions of n that have no parts in common isp(n)2−p(n−1)2−p(n−2)2+p(n−5)2+p(n−7)2−….Second, if two unlabeled rooted forests of the same number of vertices are chosen i.u.a.r., then the probability that they have no common tree is .8705… . Third, iff,gare two monic polynomials of the same degree over the fieldGF(q), then the probability thatf,gare relatively prime is 1−1/q. We give explicit involutions for the pentagonal sieve theorem, generalizing earlier mappings found by Bressoud and Zeilberger. DA - 1998/5// PY - 1998/5// DO - 10.1006/jcta.1997.2846 VL - 82 IS - 2 SP - 186-192 SN - 0097-3165 ER - TY - JOUR TI - The lack of influence of the right-hand side on the accuracy of linear system solution AU - Banoczi, JM AU - Chiu, NC AU - Cho, GE AU - Ipsen, ICF T2 - SIAM JOURNAL ON SCIENTIFIC COMPUTING AB - It is commonly believed that a fortunate right-hand side b can significantly reduce the sensitivity of a system of linear equations Ax=b. We show, both theoretically and experimentally, that this is not true when the system is solved (in floating point arithmetic) with Gaussian elimination or the QR factorization: the error bounds essentially do not depend on b, and the error itself seems to depend only weakly on b. Our error bounds are exact (rather than first-order); they are tight; and they are stronger than the bound of Chan and Foulser. We also present computable lower and upper bounds for the relative error. The lower bound gives rise to a stopping criterion for iterative methods that is better than the relative residual. This is because the relative residual can be much larger, and it may be impossible to reduce it to a desired tolerance. DA - 1998/// PY - 1998/// DO - 10.1137/S106482759630526X VL - 20 IS - 1 SP - 203-227 SN - 1064-8275 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032131636&partnerID=MN8TOARS KW - linear system KW - right-hand side KW - condition number KW - backward error KW - stopping criterion ER - TY - JOUR TI - Repair-unit location models for power failures AU - Yao, MJ AU - Min, KJ T2 - IEEE TRANSACTIONS ON ENGINEERING MANAGEMENT AB - Extreme weather conditions such as ice storms often cause significant damage to electric power transmission and distribution systems and result in large-scale power failures. In such cases, electric utilities need to repair the transmission and distribution systems as expeditiously and economically as possible. In this paper, for the electric utilities, the authors present three mathematical goal programming models: (1) a tactical model that provides the optimal repair-unit dispatch plan after a forecast of severe weather conditions; (2) a short-term strategic model that provides the optimal repair-unit location plan under normal weather conditions; and (3) a long-term strategic model that provides the optimal number of repair units. These models will assist electric utilities to locate and dispatch repair units and to restore the transmission and distribution failures efficiently. The authors illustrate some features of these models with a numerical example. Finally, a comparative study shows how these models could be more efficient than a modified conventional model. DA - 1998/2// PY - 1998/2// DO - 10.1109/17.658661 VL - 45 IS - 1 SP - 57-65 SN - 0018-9391 KW - goal programming KW - power failure KW - unit location model ER - TY - JOUR TI - Optimizing tensor product computations in stochastic automata networks AU - Fernandes, P. AU - Plateau, B. AU - Stewart, W. J. T2 - RAIRO. Recherche Operationnelle = Operations Research AB - In this paper we consider some numerical issues in computing solutions to networks of stochastic automata (SAN). In particular our concern is with keeping the amount of computation per iteration to a minimum, since iterative methods appear to be the most effective in determining numerical solutions. In a previous paper we presented complexity results concerning the vector-descriptor multiplication phase of the analysis. In this paper our concern is with optimizations related to the implementation of this algorithm. We also consider the possible benefits of grouping automata in a SAN with many small automata, to create an equivalent SAN having a smaller number of larger automata. DA - 1998/// PY - 1998/// DO - 10.1051/ro/1998320303251 VL - 32 IS - 3 SP - 325-351 ER - TY - JOUR TI - Efficient descriptor-vector multiplications in stochastic automata networks AU - Fernandes, P AU - Plateau, B T2 - JOURNAL OF THE ACM AB - This paper examines numerical issues in computing solutions to networks of stochastic automata. It is well-known that when the matrices that represent the automata contain only constant values, the cost of performing the operation basic to all iterative solution methods, that of matrix-vector multiply, is given by ρ N = Π N i-1 n i × Σ N i=1 n i , where n i is the number of states in the i th automaton and N is the number of automata in the network. We introduce the concept of a generalized tensor product and prove a number of lemmas concerning this product. The result of these lemmas allows us to show that this relatively small number of operations is sufficient in many practical cases of interest in which the automata contain functional and not simply constant transitions. Furthermore, we show how the automata should be ordered to achieve this. DA - 1998/5// PY - 1998/5// DO - 10.1145/278298.278303 VL - 45 IS - 3 SP - 381-414 SN - 1557-735X KW - generalized tensor algebra KW - Markov chains KW - stochastic automata networks KW - vector-descriptor multiplication ER - TY - JOUR TI - An approximation theory of solutions to operator Riccati equations for H(infinity) control AU - Ito, K AU - Morris, KA T2 - SIAM JOURNAL ON CONTROL AND OPTIMIZATION AB - As in the finite-dimensional case, the appropriate state feedback for the infinite-dimensional $H^\infty$ disturbance-attenuation problem may be calculated by solving a Riccati equation. This operator Riccati equation can rarely be solved exactly. We approximate the original infinite-dimensional system by a sequence of finite-dimensional systems and consider the corresponding finite-dimensional disturbance-attenuation problems. We make the same assumptions required in approximations for the classical linear quadratic regulator problem and show that the sequence of solutions to the corresponding finite-dimensional Riccati equations converge strongly to the solution to the infinite-dimensional Riccati equation. Furthermore, the corresponding finite-dimensional feedback operators yield performance arbitrarily close to that obtained with the infinite-dimensional solution. DA - 1998/1// PY - 1998/1// DO - 10.1137/S0363012994274422 VL - 36 IS - 1 SP - 82-99 SN - 0363-0129 KW - H(infinity) KW - approximations KW - partial differential equation KW - optimal control KW - infinite dimensional ER - TY - JOUR TI - The immersed interface method using a finite element formulation AU - Li, ZL T2 - APPLIED NUMERICAL MATHEMATICS AB - A finite element method is proposed for one dimensional interface problems involving discontinuities in the coefficients of the differential equations and the derivatives of the solutions. The interfaces do not have to be one of grid points. The idea is to construct basis functions which satisfy the interface jump conditions. By constructing an interpolating function of the solution, we are able to give a rigorous error analysis which shows that the approximate solution obtained from the finite element method is second order accurate in the infinity norm. Numerical examples are also provided to support the method and the theoretical analysis. Several numerical approaches are also proposed for dealing with two dimensional problems involving interfaces. DA - 1998/7// PY - 1998/7// DO - 10.1016/S0168-9274(98)00015-4 VL - 27 IS - 3 SP - 253-267 SN - 0168-9274 KW - immersed interface method KW - finite element method KW - modified basis function KW - natural jump condition KW - error analysis ER - TY - JOUR TI - Termination of Newton/Chord iterations and the method of lines AU - Kelley, CT AU - Miller, CT AU - Tocci, MD T2 - SIAM JOURNAL ON SCIENTIFIC COMPUTING AB - Many ordinary differential equation (ODE) and differential algebraic equation (DAE) codes terminate the nonlinear iteration for the corrector equation when the difference between successive iterates (the step) is sufficiently small. This termination criterion avoids the expense of evaluating the nonlinear residual at the final iterate. Similarly, Jacobian information is not usually computed at every time step but only when certain tests indicate that the cost of a new Jacobian is justified by the improved performance in the nonlinear iteration. In this paper, we show how an out-of-date Jacobian coupled with moderate ill conditioning can lead to premature termination of the corrector iteration and suggest ways in which this situation can be detected and remedied. As an example, we consider the method of lines (MOL) solution of Richards' equation (RE), which models flow through variably saturated porous media. When the solution to this problem has a sharp moving front, and the Jacobian is even slightly ill conditioned, the corrector iteration used in many integrators can terminate prematurely, leading to incorrect results. While this problem can be solved by tightening the tolerances for the solvers used in the temporal integration, it is more efficient to modify the termination criteria of the nonlinear solver and/or recompute the Jacobian more frequently. Of these two, recomputation of the Jacobian is the more important. We propose a criterion based on an estimate of the norm of the time derivative of the Jacobian for recomputation of the Jacobian and a second criterion based on a condition estimate for tightening of the termination criteria of the nonlinear solver. DA - 1998/1// PY - 1998/1// DO - 10.1137/S1064827596303582 VL - 19 IS - 1 SP - 280-290 SN - 1064-8275 KW - termination of nonlinear iterations KW - Richards' equation KW - method of lines ER - TY - PCOMM TI - Solving interval-valued fuzzy relation equations AU - Li, GZ AU - Fang, SC AB - Solving systems of fuzzy relation equations is an important topic in fuzzy set theory. This paper studies the composite interval-valued fuzzy relation equations. After analyzing the properties of its solution set, we convert the fuzzy relation equations into a fuzzy relation inequality system and propose an efficient computational procedure to generate the whole solution set. Examples are included to illustrate the idea and algorithm. DA - 1998/5// PY - 1998/5// DO - 10.1109/91.669033 SP - 321-324 KW - composite interval-valued fuzzy relation equations KW - fuzzy relation equations KW - max-min composition ER - TY - JOUR TI - Real-time monitoring of steady-state pulsed chemical beam epitaxy by p-polarized reflectance AU - Bachmann, KJ AU - Sukidi, N AU - Hopfner, C AU - Harris, C AU - Dietz, N AU - Tran, HT AU - Beeler, S AU - Ito, K AU - Banks, HT T2 - JOURNAL OF CRYSTAL GROWTH AB - The structure in the p-polarized reflectance (PR) intensity Rp4(t) - observed under conditions of pulsed chemical beam epitaxy (PCBE) - is modeled on the basis of the four-layer stack: ambient/surface reaction layer (SRL)/epilayer/substrate. Linearization of the PR intensity with regard to the phase factor associated with the SRL results in a good approximation that can be expressed as Rp4 = Rp3 + ΔRp.Rp3 is the reflectivity of the three-layer stack ambient-epilayer-substrate. ΔRp describes the properties of the SRL. An explicit relation is derived between ΔRp(t) and the time-dependent surface concentrations ch(t) (h = 1, 2, …, N) of the constituents of the SRL, which holds for conditions of submonolayer coverage of the surface by source vapor molecules. Under conditions of low temperature PCBE at high flux, the SRL is expected to exhibit nonideal behavior, mandating replacement of the surface concentrations by activities. Also, in this case, the thickness of the SRL must be represented in terms of partial molar volumina Vh. Since the relation between ΔRp(t) and the activities of reactants, intermediates and products of the chemical reactions driving heteroepitaxial growth is non-linear, the extraction of kinetic parameters from the measured time dependence of the PR signal generally requires numerical modeling. DA - 1998/1// PY - 1998/1// DO - 10.1016/s0022-0248(97)00410-7 VL - 183 IS - 3 SP - 323-337 SN - 0022-0248 KW - p-polarized reflectance KW - surface kinetics KW - chemical beam epitaxy KW - real-time process monitoring ER - TY - JOUR TI - On the structure of stochastic matrices with a subdominant eigenvalue near 1 AU - Hartfiel, DJ AU - Meyer, CD T2 - LINEAR ALGEBRA AND ITS APPLICATIONS AB - An n × n irreducible stochastic matrix P can possess a subdominant eigenvalue, say λ2(P), near λ = 1. In this article we clarify the relationship between the nearness of these eigenvalues and the near-uncoupling (some authors say “nearly completely decomposable”) of P. We prove that for fixed n, if λ2(P) is sufficiently close to λ = 1, then P is nearly uncoupled. We then provide examples which show that λ2(P) must, in general, be remarkably close to 1 before such uncoupling occurs. DA - 1998/3/15/ PY - 1998/3/15/ DO - 10.1016/s0024-3795(97)00333-9 VL - 272 SP - 193-203 SN - 0024-3795 ER - TY - JOUR TI - A fast multilevel algorithm for the solution of nonlinear systems of conductive-radiative heat transfer equations AU - Banoczi, JM AU - Kelley, CT T2 - SIAM JOURNAL ON SCIENTIFIC COMPUTING AB - In this paper we describe and analyze a fast multilevel algorithm for the solution of a system of nonlinear integro-differential equations that model steady-state combined conductive-radiative heat transfer. This system of equations for radiative intensity and temperature can be formulated as a compact fixed point problem in temperature alone with a fixed point map that requires both a solution of the linear transport equation and the linear heat equation for its evaluation. We obtain an efficient evaluation of the fixed point map by coupling a finite element diffusion solver with a fast transport solver developed by the second author. As a solver we apply a modification of the Atkinson--Brakhage method, with Newton--GMRES as the coarse mesh solver, to the full nonlinear system. We compare our discretization/solver pair with Newton--GMRES and the classical Atkinson--Brakhage algorithm. DA - 1998/1// PY - 1998/1// DO - 10.1137/S1064827596302965 VL - 19 IS - 1 SP - 266-279 SN - 1064-8275 KW - conductive-radiative heat transfer KW - multilevel algorithm KW - compact fixed point problems ER - TY - JOUR TI - Intractability of the dial-a-ride problem and a multiobjective solution using simulated annealing AU - Baugh, JW AU - Kakivaya, GKR AU - Stone, , JR T2 - ENGINEERING OPTIMIZATION AB - Abstract Numerous techniques for generating approximate solutions have been proposed in the last decade for routing and scheduling in multi-vehicle dial-a-ride problems. While some of these techniques have mathematical foundations, it is often difficult to assess the global optimality of the generated solution due to the use of pure local improvement methods. In additon, most of these methods are based on a single objective, such as minimization of the number of vehicles used, and cannot account for different or competing objectives that characterize the problem. This paper proves the intractability of the dial-a-ride problem, and then describes a new approximate method based on simulated annealing that is used to solve these problems in the presence of multiple objectives. DA - 1998/// PY - 1998/// DO - 10.1080/03052159808941240 VL - 30 IS - 2 SP - 91-123 SN - 0305-215X UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0031680443&partnerID=MN8TOARS KW - dial-a-ride problem KW - simulated annealing KW - multiobjective programming KW - decision-support systems ER - TY - JOUR TI - The idea behind Krylov methods AU - Ipsen, ICF AU - Meyer, CD T2 - AMERICAN MATHEMATICAL MONTHLY AB - Click to increase image sizeClick to decrease image size Additional informationNotes on contributorsIlse C. F. IpsenILSE IPSEN received a Vordiplom in computer science/mathematics from the Universität Kaiserslautern in Germany and a Ph.D. in computer science from Penn State. Before joining the Mathematics Department at North Carolina State University she taught computer science at Yale. Her research interests include numerical linear algebra and scientific computing.Carl D. MeyerCARL MEYER is a professor of Mathematics at North Carolina State University. He received an undergraduate degree in mathematics from the University of Northern Colorado and a Masters and Ph.D. degree in mathematics from Colorado State University. His research interests include matrix and numerical analysis, and applied probability. He has served as Managing Editor for the SIAM Journal on Algebraic and Discrete Methods (now SIMAX), and he is the author of a new text, Matrix Analysis and Applied Linear Algebra. DA - 1998/12// PY - 1998/12// DO - 10.2307/2589281 VL - 105 IS - 10 SP - 889-899 SN - 1930-0972 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032280255&partnerID=MN8TOARS ER - TY - JOUR TI - Solving fuzzy inequalities with concave membership functions AU - Hu, CF AU - Fang, SC T2 - FUZZY SETS AND SYSTEMS AB - Solving systems of fuzzy inequalities could lead to the solutions of fuzzy mathematical programs. It is shown that a system of fuzzy inequalities with concave membership functions can be converted to a regular convex programming problem. A “method of centres” with “entropic regularization” techniques is proposed for solving such a problem. Some computational results are included. DA - 1998/10/16/ PY - 1998/10/16/ DO - 10.1016/S0165-0114(97)00013-4 VL - 99 IS - 2 SP - 233-240 SN - 1872-6801 KW - fuzzy mathematical programming KW - fuzzy membership functions KW - systems of fuzzy inequalities ER - TY - JOUR TI - Power additivity and orthogonality AU - Hartwig, RE AU - Semrl, P T2 - SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS AB - The relation between rank additivity and orthogonality is analyzed. The central role played by Cochran's theorem is illustrated and the properties of orthogonal and power-additive families are investigated. DA - 1998/9/16/ PY - 1998/9/16/ DO - 10.1137/S089547989731498X VL - 20 IS - 1 SP - 1-13 SN - 0895-4798 KW - power additivity KW - rank additivity KW - orthogonality KW - Cochran's theorem ER - TY - JOUR TI - Personal assistants AU - Huhns, MN AU - Singh, MP T2 - IEEE INTERNET COMPUTING AB - The agent metaphor comes packaged with a number of powerful abstractions. Some of these are psychological, such as beliefs, knowledge, and intentions-abstractions that were traditionally studied in AI. However, there are a number of other abstractions that the agent metaphor brings to the fore. Of these, one has been emphasizing the social abstractions. Close cousins of the social abstractions are the ethical and legal abstractions. These too are being recognized as increasingly important in developing agents that are not only sociable, but also well behaved. DA - 1998/// PY - 1998/// DO - 10.1109/4236.670692 VL - 2 IS - 5 SP - 90-92 SN - 1089-7801 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-11644317014&partnerID=MN8TOARS ER - TY - JOUR TI - Note. Satisfying due dates in large job shops AU - Hodgson, TJ AU - Cormier, D AU - Weintraub, AJ AU - Zozom, A T2 - MANAGEMENT SCIENCE AB - For the multi-machine job shop scheduling problem, a conceptually simple simulation-based procedure (first proposed by Lawrence and Morton 1986) is shown to be both effective and efficient in providing optimal, or near optimal, schedules for minimizing the maximum lateness, L max . Computational experimentation is used to identify the conditions under which the approach is most viable. DA - 1998/10// PY - 1998/10// DO - 10.1287/mnsc.44.10.1442 VL - 44 IS - 10 SP - 1442-1446 SN - 0025-1909 KW - job shop scheduling KW - maximum lateness KW - simulation ER - TY - JOUR TI - Decision support system for lumber procurement and dry kiln scheduling AU - Huang, J.-C. AU - Culbreth, C.T. AU - Joines, J.A. AU - King, R.E. AU - Hodgson, T.G. T2 - Forest Products Journal DA - 1998/// PY - 1998/// VL - 48 IS - 9 SP - 51-59 ER - TY - JOUR TI - Cognitive agents AU - Huhns, MN AU - Singh, MP T2 - IEEE INTERNET COMPUTING AB - Several researchers have proposed using cognitive concepts as a semantic basis for agent communications (M.N. Huhns and M.P. Singh, 1997). One of the leading candidates for such a semantics is based on Arcol, the communication language used within Artimis. Interestingly, this application (not only of Arcol, but also in general) appears extremely misguided. The intentional concepts are well suited to designing agents, but are not suited to giving a basis to a public, standardizable view of communication. A challenge for using the cognitive concepts is that although they are natural in several respects and can guide implementations, full blown implementations that try to be faithful to every aspect of the model can end up being computationally demanding. As the cognitive concepts are put to use in real applications, the principles for simplifying the implementations will emerge. In any case, because of their naturalness to humans, the cognitive concepts are here to stay, and we will do well to consider them in the design of our agents. DA - 1998/// PY - 1998/// DO - 10.1109/4236.735992 VL - 2 IS - 6 SP - 87-89 SN - 1941-0131 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0010221078&partnerID=MN8TOARS ER - TY - JOUR TI - Behavior of the nonunique terms in general DAE integrators AU - Campbell, SL AU - Yeomans, KD T2 - APPLIED NUMERICAL MATHEMATICS AB - Differential algebraic equations (DAEs) are implicit systems of ordinary differential equations F(y′, y, t) = 0. DAEs arise in many applications and a variety of numerical methods have been developed for solving DAEs. Numerical methods have been proposed for integrating general higher index DAEs and successfully applied to test problems. These methods require solving a nonlinear system of equations which is larger than the original DAE at each time step. For fully implicit problems part of the solution of the nonlinear system is not uniquely determined. This poses questions about the effects of predictors and also a possible instability in the growth of these terms during a numerical integration. In this paper it is shown that the nonunique component is actually the numerical solution of an auxiliary DAE which depends not only on the original DAE but also on the predictor being used in the Gauss-Newton iteration. As an important consequence we both establish a basis for the design of low order integrators for high index DAEs and develop guidelines for the use of predictors in integrating general high index DAEs. DA - 1998/10// PY - 1998/10// DO - 10.1016/S0168-9274(98)00044-0 VL - 28 IS - 2-4 SP - 209-226 SN - 0168-9274 KW - differential algebraic equation KW - DAE KW - numerical methods ER - TY - JOUR TI - All agents are not created equal AU - Huhns, M.N. AU - Singh, Munindar P. T2 - IEEE Internet Computing AB - As the technology advances, we can expect the development of specialized agents to be used as standardized building blocks for information systems. Two trends lend credence to such a prediction. First, software systems in general are being constructed with larger components, such as ActiveX and JavaBeans, which are becoming closer to being agents themselves. They have more functionality than simple objects, respond to events autonomously, and, most importantly, respond to system builders at development time, as well as to events at runtime. Moreover, there is a move toward more cooperative information systems, in which the architecture itself plays an important role in the effectiveness of the system, as opposed to traditional software systems where effectiveness depends on the quality of the individual components. These architectures are generating a set of standardized agents. Architectures based on standardized agent types should be easier to develop, understand, and use. Perhaps most important of all, these architectures will make it easier for separately developed information systems to interoperate. DA - 1998/// PY - 1998/// DO - 10.1109/4236.683806 VL - 2 IS - 3 SP - 94-96 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-11344261363&partnerID=MN8TOARS ER - TY - JOUR TI - Agent communication languages: Rethinking the principles AU - Singh, MP T2 - COMPUTER AB - Agent communication languages have been used for years in proprietary multiagent systems. Yet agents from different vendors-or even different research projects-cannot communicate with each other. The author looks at the underlying reasons and proposes a conceptual shift from individual agent representations to social interaction. DA - 1998/12// PY - 1998/12// DO - 10.1109/2.735849 VL - 31 IS - 12 SP - 40-+ SN - 0018-9162 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032294174&partnerID=MN8TOARS ER - TY - JOUR TI - A nonlinear optimal control method for magnetostrictive actuators AU - Smith, RC T2 - JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES AB - This paper addresses the development of a nonlinear optimal control methodology for magnetostrictive actuators. At moderate to high drive levels, the output from these actuators is highly nonlinear and contains significant magnetic and magnetomechanical hysteresis. These dynamics must be accommodated by models and control laws to utilize the full capabilities of the actuators. A characterization based upon ferromagnetic mean field theory provides a model which accurately quantifies both transient and steady state actuator dynamics under a variety of operating conditions. The control method consists of a linear perturbation feedback law used in combination with an optimal open loop nonlinear control. The nonlinear control incorporates the hysteresis and nonlinearities inherent in the transducer and can be computed offline. The feedback control is constructed through linearization of the perturbed system about the optimal system and is efficient for online implementation. As demonstrated through numerical examples, the combined hybrid control is robust and can be readily implemented in linear PDE-based structural models. DA - 1998/6// PY - 1998/6// DO - 10.1177/1045389X9800900608 VL - 9 IS - 6 SP - 468-486 SN - 1045-389X ER - TY - JOUR TI - Utilization of coupling effects in compensator design for structural acoustic systems AU - Banks, HT AU - Demetriou, MA AU - Smith, RC T2 - JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA AB - The quantification and utilization of coupling effects in a prototypical structural acoustic system are examined in this paper. In typical systems, the coupling mechanisms are manifested in two ways. The first leads to the transfer of energy from an ambient field to an adjacent structure and is often responsible for exogenous structural excitation. The second involves the transfer of energy from the vibrating structure to an adjacent field. This is the source of structure-borne noise and is ultimately the mechanism through which structural actuators are utilized to attenuate noise. The examples presented here demonstrate that in fully coupled systems, both mechanisms should be incorporated to accurately model system dynamics. The examples also illustrate advantages and limitations of compensators which utilize the accurate modeling of the structural coupling. DA - 1998/2// PY - 1998/2// DO - 10.1121/1.421205 VL - 103 IS - 2 SP - 872-887 SN - 0001-4966 ER - TY - JOUR TI - The Trotter-Kato theorem and approximation of PDEs AU - Ito, K AU - Kappel, F T2 - MATHEMATICS OF COMPUTATION AB - We present formulations of the Trotter-Kato theorem for approximation of linear C 0 {}_0 -semigroups which provide very useful framework when convergence of numerical approximations to solutions of PDEs are studied. Applicability of our results is demonstrated using a first order hyperbolic equation, a wave equation and Stokes’ equation as illustrative examples. DA - 1998/1// PY - 1998/1// DO - 10.1090/S0025-5718-98-00915-6 VL - 67 IS - 221 SP - 21-44 SN - 0025-5718 KW - semigroups of transformations KW - Trotter-Kato-theorems KW - numerical approximation of linear evolutionary equations ER - TY - JOUR TI - Observer design for general linear time-invariant systems AU - Nikoukhah, R AU - Campbell, SL AU - Delebecque, F T2 - AUTOMATICA AB - It is noted that, for both explicit and implicit linear systems, several observer design problems, including system inversion, for systems with or without unknown inputs can all be formulated as a single problem involving descriptor systems. The method used for solving this problem is based on recursively applying the reduction operation which consists of identifying and discarding equations that do not provide useful information for the estimation problem. The reduction algorithm produces a reduced dimension system for which standard observers can be constructed. The method presented can be implemented using numerically robust algorithms. One such algorithm is presented. DA - 1998/5// PY - 1998/5// DO - 10.1016/S0005-1098(98)00003-X VL - 34 IS - 5 SP - 575-583 SN - 0005-1098 KW - observers KW - unknown input observers KW - system inversion KW - linear systems KW - descriptor systems ER - TY - JOUR TI - Local convergence of the symmetric rank-one iteration AU - Kelley, CT AU - Sachs, EW T2 - COMPUTATIONAL OPTIMIZATION AND APPLICATIONS DA - 1998/1// PY - 1998/1// DO - 10.1023/A:1018330119731 VL - 9 IS - 1 SP - 43-63 SN - 0926-6003 KW - SRI update KW - pointwise quasi-Newton method KW - optimal control ER - TY - JOUR TI - Convergence analysis of pseudo-transient continuation AU - Kelley, CT AU - Keyes, DE T2 - SIAM JOURNAL ON NUMERICAL ANALYSIS AB - Pseudo-transient continuation ($\Psi$tc) is a well-known and physically motivated technique for computation of steady state solutions of time-dependent partial differential equations. Standard globalization strategies such as line search or trust region methods often stagnate at local minima. \ptc succeeds in many of these cases by taking advantage of the underlying PDE structure of the problem. Though widely employed, the convergence of \ptc is rarely discussed. In this paper we prove convergence for a generic form of \ptc and illustrate it with two practical strategies. DA - 1998/4// PY - 1998/4// DO - 10.1137/S0036142996304796 VL - 35 IS - 2 SP - 508-523 SN - 0036-1429 KW - pseudo-transient continuation KW - nonlinear equations KW - steady state solutions KW - global convergence ER - TY - JOUR TI - A reduced-order method for simulation and control of fluid flows AU - Ito, K AU - Ravindran, SS T2 - JOURNAL OF COMPUTATIONAL PHYSICS AB - This article presents a reduced-order modeling approach for simulation and control of viscous incompressible flows. The reduced-order models suitable for control and which capture the essential physics are developed using the reduced-basis method. The so-called Lagrange approach is used to define reduced bases and the basis functions in this approach are obtained from the numerical solutions. The feasibility of this method for flow control is demonstrated on boundary control problems in closed cavity and in wall-bounded channel flows. Control action is effected through boundary surface movement on a part of the solid wall. Our formulation of the reduced-order method applied to flow control problems leads to a constrained minimization problem and is solved by applying Newton-like methods to the necessary conditions of optimality. Through our computational experiments we demonstrate the feasibility and applicability of the reduced-order method for simulation and control of fluid flows. DA - 1998/7/1/ PY - 1998/7/1/ DO - 10.1006/jcph.1998.5943 VL - 143 IS - 2 SP - 403-425 SN - 1090-2716 KW - reduced-basis method KW - reduced-order modeling KW - Navier-Stokes equations KW - finite element KW - optimal control ER - TY - JOUR TI - A fuzzy due-date bargainer for the make-to-order manufacturing systems AU - Wang, DW AU - Fang, SC AU - Hodgson, TJ T2 - IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS PART C-APPLICATIONS AND REVIEWS AB - For a make-to-order manufacturing system, the uncertainty and flexibility of the due dates required by customers and the production capacity owned by the manufacturer can be modeled in a fuzzy environment. A combined due-date assignment and production planning methodology for the make-to-order manufacturing systems is developed. The fuzzy approach determines the optimal due dates for the manufacturer based upon a rough-cut resource balance, while a customer can request earlier due dates by paying a higher price to cover the extra manufacturing cost incurred. The resulting fuzzy due-date bargainer is exercised using manufacturing resource planning (MRP-II) data from a furniture manufacturing company. Experimental results indicate its potential as a useful tool for real applications. DA - 1998/8// PY - 1998/8// DO - 10.1109/5326.704596 VL - 28 IS - 3 SP - 492-497 SN - 1558-2442 KW - branch-and-bound KW - due-date assignment KW - fuzzy optimization KW - just-in-time (JIT) KW - MRP-II KW - production planning ER -