SCM Researcher 2 -- David Wu

David Wu:
http://www.lehigh.edu/~sdw1/index.htm
Research Field:

Iacocca Professor and Dean
P.C. Rossin College of Engineering and Applied Science
LEHIGH UNIVERSITY

19 Memorial Drive West
Bethlehem, PA 18015
tel: 610. 758.5308
e-mail: david.wu@lehigh.edu

Teaching

Operations Research and Logistics

IE 316 Advanced Operations Research Topics
IE 395 Supply Chain Logistics

IE 412 Quantitative Models in Supply Chain Management
IE 405 Discrete Optimization
IE 411 Networks and Graphs
IE 429 AI Techniques in Combinatorial Optimization
IE 405-I Design of Manufacturing and Logistics Systems
IE 405-II Mathematical Modeling of Manufacturing
and Logistics Systems
IE 498 Probabilistic Reasoning Methods in Decision Analysis
MSE 425 Production Planning and Resource Allocation

Research

Manufacturing, Production and Logistics Systems

This area of research is motivated by industry interactions over the past ten years with Bethlehem Steel, Lucent Technologies, Ford Motor Company, UPS, PP&L, Unisys and a number of medium size manufacturing companies. While my earlier research focused on planning and scheduling robustness, the industry interaction has broadened my interests considerably. Along with my colleagues we identified a new focus in manufacturing called Manufacturing Logistics, referring to the planning, coordination, and integration issues among manufacturing facilities. My particular interest is in the coordination of production and shipment planning in manufacturing supply chains (specifically, automotive and electronics supply chains). In 1995, I co-founded the Manufacturing Logistics Institute (MLI), a research group conducting academic research on real industry problems. We have been quite successful in getting NSF and private sector supports for these research activities (a MLI brochure summarizing current projects is attached). More excitingly, MLI has assumed a leadership role in charting a national research agenda in manufacturing and logistics. In May 29-30, 1997, MLI hosted an NSF workshop on Manufacturing Logistics where more than 100 academic and industry researchers attended. After lively discussion and many debates, a comprehensive outline of future research directions was put into shape. In 1998, a workshop organized for UPS will take place, focusing on Supply Chain Integration services for their regional and worldwide customers.

Specific Topics:

• Planning and Scheduling Robustness, Assembly Design
• Supply Chain Integration via Coordinated Manufacturing Planning
• Capacity Planning, Configuration, and Allocation for Semiconductor Facilities
• Demand Characterization in Electronics and Automotive Supply Chains
• Sipment Planning to Achieve Supply Chain Lead Time Reduction

  This line of research has been supported by several NSF grants, and several grants provided by the industry. I have collaborated many of these activities with Bob Storer and Laura Burke and this has been the subject of a few dissertations by my Ph.D. students Mary J. Meixell, Kadir Ertogral, Kedar Naphade, Jorge Leon, Eui-Seok Byeon, Michael Bartolacci, Jewel Bonser and Michael Chang, and master's students Phil Brennan, Nabeela Al-Refai, Hakan Gobashi and Koichi Tsuruta.

Distributed and Game Theoretic Decision Processes

My research in this area examines theories and analytic tools basic to various industrial decision processes. My focus has been to methods that reconcile centralized, monolithic planning processes with distributed, multi-facet operational environments. This entails theories and models that reconcile a priori stochastic analysis with dynamic recourse policies, reconcile global strategic objectives (e.g., business planning) with local constraints/ preferences (e.g., manufacturing operations), and reconcile aggregated a priori information (e.g., forecast, market analysis) with actual observations over time (e.g., actual demand, sales data). Techniques rooted in graph theory, mathematical programming, game/group decision theory, and robust /stochastic optimization provide me with the primary tools to address these problems. Most research are motivated by experiences from modeling real industrial planning systems.

Specific Topics:

• Distributed Decision Making
• Auction and Bidding Models
• Mapping Distributed and Monolithic Optimization Models
• Graph-Theoretic Decomposition
• Lagrangean Methods for Model Preprocessing
• Robust A Priori Optimization
• Applications: Supplier Management, Networks Traffic Management, Reconcile Contracted and Short-Term Procurement Decisions (PP&L), Reconcile Centralized Resources with Multi-Facet, Market Specific Requirements (Ford, Lucent), Reconcile Forecasted and Actual Demand Information (Lucent), Reconcile Business Planning with Manufacturing Process Design (Bethlehem Steel)

  This line of research has been supported by an NSF grant and a grant from U.S. Air Force, and several grants provided by the industry. I have collaborated many of these activities with Pat Harker at the University of Pennsylvania and this has been the subject of a few dissertations by my Ph.D. students Erhan Kutanoglu, Suleyman Karabuk, and Hakan Golbasi.

Discrete and Combinatorial Optimization

My focus in this area is to develop search algorithms, decomposition schemes, relaxation methods and other computational techniques that allow the efficient solution of optimization problems. Of special interests are discrete and combinatorial optimization. The research is motivated by special structures often observed in real-world optimization problems, which provide insights for efficient algorithm design. Research has been conducted in construction project management (ATLSS), production scheduling (Neapco, Bethlehem Steel, Tray-Pak), critical resource scheduling (Bethlehem Steel), software project management (UNISYS), VLSI design and routing problems (AT&T), telecommunication network routing, and assembly design and planning problems.

Specific Topic Areas:

• Specialized Search Algorithms: Problem Space Search, Simulated Annealing, Genetic Algorithms
• Lagrangean Heuristics
• Graph Theoretic Algorithms
• Ordinal Comparison of Algorithms
• Special Structures in Scheduling and Routing Problems

I have collaborated with Bob Storer on many of these problems. The students I have collaborated with in this line of research includes Kedar Naphade , Mike Bartolacci, I.-K. Park (Ph.D. students), and Ranzo Vaccari, Bhavin Doshi, Jaime Bustos (Master's).

Quantitative Supply Chain Analysis (New)

"Managing Capacity in the High-Tech Industry: A Review of Literature," S. D. Wu, M. Erkoc, and S. Karabuk, (new 2005), Click here to view the PDF document.

"Managing Short-Lifecycle Technology Products for Agere Systems," S. D. Wu, B. Aytac, R. Berger, and C. Armbruster (new 2005), Click here to view the PDF document.

"Repeated Procurement Auctions with U-Shpaed Cost Functions: Competitive Equilibrium Analysis," S. Ozkan and S. D. Wu, (new 2005), Click here to view the PDF document.

"Supplier Coalition Formation in Buyer-Oriented Market," S. Oshkai and S. D. Wu, (new 2005), Click here to view the PDF document.

Supply Chain Planning and Coordination

• "Managing High-Tech Capacity Expansion Via Reservation Contracts," M. Erkoc and S.D. Wu, (Updated June 2005) click here to view the PDF document.
• "Incentive Schemes for Semiconductor Capacity Allocation: A Game Theoretic Analysis," S. Karabuk and S.D. Wu, (updated June 2005), click here to view the PDF document.
• "Supply Chain Intermediation: A Bargaining Theoretic Framework," S.D. Wu, (new, May 2004) click here to view the PDF document.
• "Coordinating Supplier Competition via Auctions," M. Jin and S.D. Wu, (updated August 2004), click here to view the PDF document.
• "Modeling Capacity Reservation in High-Tech Manufacturing," M. Jin and S.D. Wu, (Updated December 2001), click here to view the PDF document.
• "Lead Time Coordination Between Marketing and Operations in an Internal Market," H. Golbasi and S.D. Wu, (updated June 2001), click here to view the PDF document.
• "Due-Date Coordination in an Internal Market via Risk Sharing," M. Erkoc and S.D. Wu, click here to view the PDF document.
• "Decentralizing Semiconductor Capacity Planning via Internal Market Coordination," S. Karabuk and S.D. Wu, click here to view the PDF document.
• "Procurement Auction with Supplier Coalitions: Validity Requirements and Mechanism Design," M. Jin and S.D. Wu, click here to view the PDF document. (Updated July 2002)
• "A Bargaining Game for Supply Chain Contracting," K. Ertogral and S.D. Wu, click here to view the PDF document.
• "Strategic Capacity Planning in the Semiconductor Industry: A Stochastic Programming Approach," S. Karabuk and S. D. Wu, click here to view the PDF document.
• "Manufacturing Planning Over Alternative Facilities: Modeling, Analysis and Algorithms," S.D Wu and H. Golbasi, click here to view the PDF document.
• "Auction-Theoretic Coordination of Production Planning in the Supply Chain," K. Ertogral and S.D. Wu, click here to view the PDF document.
• "Scenario Analysis of Demands in a Technology Market Using Leading Indicators," M.J. Meixell and S.D. Wu, click here to view the PDF document.
• "Relating Demand Behavior and Production Policies in the Manufacturing Supply Chain," S.D. Wu and M.J. Meixell, IMSE Technical Report 98T-007, submitted for publication, click here to view the PDF document.
• "Integrating Production and Transportation Logistics in a Supply Chain Environment: A Lagrangean Decomposition Approach," K. Ertogral, S.D. Wu and L.I. Burke, IMSE Technical Report 98T-008, click to view the paper in PDF format.
• "A Multistage Stochastic Linear Program for Annual Capacity Planning," R. Christie and S.D. Wu, IMSE Technical Report 97T-004, 1997.
• "Integrating Manufacturing Planning with Multiple Supply Chain Management: Models and Analysis," M. Meixell and S.D. Wu, IMSE Technical Report, 96W-005, 1996.
• "A Multi-Stage Stochastic Programming Model for Fuel Procurement Problems," J.S. Bonser, S.D. Wu and R.H. Storer, IMSE Technical Report 96T-014,1996.
• "Demand Propagation in Manufacturing Supply Chains: A Multi-Period Production Model," M. Meixell and S. D. Wu, manuscript under preparation.
• "Improving Melt Scheduling in Steel Manufacturing Processes," K.S. Naphade, S.D. Wu, R.H. Storer, and B.J. Doshi, submitted for publication, under review, click here to view the PDF document.
• "Graph-Theoretic Generation of Assembly Plans, Part I: Correct Generation of Precedence Graphs," K.S. Naphade, R.H. Storer, and S.D. Wu, submitted for publication, under review, click here to view the PDF document.
• "Graph-Theoretic Generation of Assembly Plans, Part II: Problem Decomposition and Optimization Algorithms," K.S. Nahpade, S.D. Wu and R.H. Storer, submitted for publication, under review, click here to view the PDF document
• "Manufacturing Logistics Research: Taxonomy and Directions," S.David Wu, Robin Roundy, Rober H. Storer and Louis A. Martin-Vega, submitted for publication, click here to view the PDF document.

Robust Optimization and Graph Theoretic Decomposition

• "A Graph-Theoretic Decomposition of Job Shop Scheduling Problems to Achieve Scheduling Robustness", S.D. Wu, E.S. Byeon, and R.H. Storer; Operations Research, Vol 47, Number 1, 1999. pp113-124.
• "Decomposition Heuristics for Robust Job-Shop Scheduling", E.S. Byeon, S.D. Wu, and R.H. Storer; IEEE Transactions on Robotics and Automation (forthcoming).
• "A Local Search Method for Robust and Adaptable Job Shop Scheduling," P. Brennan and S. D. Wu, Technical Report 95T-006, Department of IMSE, Lehigh University, Submitted for publication.
• "Robust Scheduling via Disjunctive Graph Pre-Processing – A Computational Study," S.D. Wu, P. Brennan, and K. Tsuruta, submitted to INFORMS Journal on Computing, under review.
• "Robust Job-Shop Scheduling: a Simulation Study", E.S. Byeon, S.D. Wu, and R.H. Storer, in Proceeding of the Third Industrial Engineering Research Conference, L. Burke and J. Jackman (eds.), 1994, pp. 666-670, Atlanta,

  — Applied to Procurement Planning

  • "A Procurement Planning Model Integrating Strategic Planning with Dynamic Purchasing Decisions," Bonser, J. and S.D. Wu, To appear, Management Science.

  
  — Applied to Telecommunication Networks Routing
  

  • "A Path Constrained Approach to Dynamic Network Routing: A Virtual Clustering and Flow Deviation Algorithm," IMSE Technical Report, 98T-005, 1998.
  • "A Virtual Clustering Approach for Routing Problems in Telecommunication Networks," M.R. Bartolacci and S.D. Wu, INFORMS Journal on Computing, Vol . 10, No. 1, 1998, pp. 12-24.
  • "A Search Heuristic for Single Path and Bifurcated Routing in Wide Area Communication Networks," M.R. Bartolacci and S.D. Wu, Annals of OR, under revision.
  • "A Routing Optimization Model for Communication Networks Subject to Traffic Fluctuation and Component Failures," M.R. Bartolacci and S.D. Wu, in Proceedings, Manufacturing Systems Engineering 8th Conference with Industry, 1994, pp. 89-96.
  • "An Adaptable Routing Optimization Model for Communication Networks," M.R. Bartolacci and S.D. Wu, in Proceedings, the Third International Conference on Telecommunication Systems, Modeling and Analysis, 1995.
  
  
  

  — Applied to Process Planning and Scheduling
  

  • "Integrating Process Planning and Scheduling Decisions in a Machine Shop Environment," N. Al-Refai and S.D. Wu, Technical Report 96T-008, Department of Industrial and Manufacturing Systems Engineering, Lehigh University.

Rescheduling Algorithms

• "One-Machine Rescheduling Heuristics with Efficiency and Stability as Criteria," Wu, S.D., Storer, R.H. and Chang, P.C., Computers and Operations Research, Vol. 20, No.1, 1993, pp.1-14.
• "A Rescheduling Procedure for Manufacturing Systems Under Random Disruptions," u, S.D., Storer, R.H. and Chang, P.C., in New Directions for Operations Research in Manufacturing, T. Gulledge and A. Jones (eds), Springer-Verlag, 1991.

Game Theoretic Analysis

• "A Game Theoretic Approach for Job Shops in the Presence of Random Disruptions", Leon,V.J., Wu, S.D., and Storer, R.H., International Journal of Production Research, Vol. 32, No.6, 1994, pp. 1451-1476.
• "A Decision Structure Using Generalized AND/OR Trees Containing Chance Nodes," Wu, S.D. and Leon,V.J., Computer & Industrial Engineering, Vol. 22, No. 1, 1994, pp.151-171.
• "Robust Scheduling and Game-Theoretic Control for Short-Term Scheduling of Job Shops", V.J. Leon, S.D. Wu, and R.H. Storer, in Operations Research in Production Planning and Control, G. Fandel, T. Gulledge, and A. Jones (eds.), Springer-Verlag, 1993.

Bircriterion Optimizaiton

• "A Bi-Level Local Search Algorithm for Heavily Constrained Bi-Criterion Scheduling ProblemsAn Adaptive Local Search Method for Heavily Constraint Multi-Objective Scheduling," K.Naphade, B.J. Doshi, S.D. Wu, and R.H. Storer, submitted to Proceedings, IE Research Conference.
• "A Bi-level Local Search Method for the Melt Scheduling Problem at BethForge," B. Dhoshi, S.D. Wu, and R.H. Storer, in Proceedings IE Research Conference, Minneapolis , May 1996.
• "A Rescheduling Procedure for Manufacturing Systems Under Random Disruptions," u, S.D., Storer, R.H. and Chang, P.C., in New Directions for Operations Research in Manufacturing, T. Gulledge and A. Jones (eds), Springer-Verlag, 1991.
• "One-Machine Rescheduling Heuristics with Efficiency and Stability as Criteria," Wu, S.D., Storer, R.H. and Chang, P.C., Computers and Operations Research, Vol. 20, No.1, 1993, pp.1-14.

Robust Scheduling and Control

• "Robustness Measures and Robust Scheduling for Job Shops," Leon, V. J., Wu, S.D. and Storer, R. H., IIE Transactions, Vol. 26, No. 5, 1994, pp. 32-43.
• "A Bidirectional Inference Engine for the Planning and Control of Manufacturing Systems," Wu, S.D. and Wysk, R.A., Computers & Industrial Engineering, Vol. 18, No. 3, 1990.
• "Job Scheduling with Random Objective Functions," Storer, R.H. and Wu, S.D. in Proceedings of the First IIE Research Conference, May 20-21, 1992, 401-403, Chicago, Ill.
• "A Multi-Pass Expert Control System for Flexible Manufacturing Systems," Wysk, R.A., Wu, S.D. and Yang, N.S., ASME Bound Volume of the Symposium on Integrated and Intelligent Manufacturing, 1986.
• "Scheduling, Control and Rescheduling Methodologies for Job-Shops in the Presence of Disruptions," Wu, S.D., V.J. Leon and R.H. Storer, in Proceedings, NSF Design and Manufacturing Systems Grantees Conference, January, 1992.
• "Scheduling, Control and Rescheduling Methodologies for Uncertain Manufacturing Environments," Wu, S.D., in Proceedings, NSF Design and Manufacturing Systems Grantees Conference, January, 1991.

Scheduling with Vacations

• "On Scheduling with Ready-Times, Due-Dates and Vacations," Leon, V.J. and Wu, S.D. Naval Research Logistics, Vol. 39, 1992, pp.53-65.
• "Generation and Control of Job-Shop Schedules in Failure Prone Production Systems," Wu, S.D., Leon, V.J., and Storer, R.H. in Proceedings of the First IIE Research Conference , May 20-21, 1992, 391-394, Chicago, Ill.

Survey and Overview in Scheduling

• "A Survey of Commercial Scheduling Packages," S.D. Wu, Technical Report to the National Institute of Standard and Technologies, 1995.
• "Advantages of Scaled and Unscaled Physical Models for FMS Research and Instruction," Wysk, R.A., Ghosh, B.K., Cohen, P.H. and Wu, S.D., Journal of Manufacturing Systems, Vol. 6, No. 2, 1987.
• "Characteristics of Computerized Scheduling and Control of Manufacturing Systems", V.J. Leon and S. D. Wu, in Computer Control of Flexible Manufacturing Systems, S. Joshi and J. Smith (ed.), Chapman & Hall, London, U.K., 1994, pp. 63-74.
• "Scheduling, Optimization and Control of Automated Systems," Advances in Control & Dynamic Systems: Advances in Manufacturing and Automation Systems, C.T. Leondes (Edited), Academic Press, Wu, S. D. and Wysk, R.A., pp. 51-76, Vol. 47., Academic Press, 1991.
• "Integrated Computer-Aided Manufacturing," in Computer-Aided Manufacturing, T.C. Chang, R.A. Wysk and H.P. Wang, Prentice-Hall Inc., 1991.

Discrete Event Simulation and Scheduling

• "An Application of Discrete-Event Simulation to On-Line Control and Scheduling of Flexible Manufacturing," Wu, S.D. and Wysk, R.A., International Journal of Production Research, Vol. 27, No. 9, 1989.
• "Multi-pass Expert Control System- A Control/Scheduling Structure for Flexible Manufacturing Cells," Wu, S.D. and Wysk, R.A., Journal of Manufacturing Systems, Vol. 7, No. 2, 1988.
• "Artificial Intelligence and Scheduling Applications," Wu, S.D.,Artificial Intelligence in Manufacturing: Theory and Practice, S. Kumara, R.L. Kashyap and A.L. Soyster (eds), Institute of Industrial Engineers, 1988.
• "Genic- A Generic CNC Emulator"Wu, S.D., Computer Aided Manufacturing: PC Application Software, R.A. Wysk,T.C. Chang and H.P. Wang, Delmar Publishers, Albany, New York, 1988.
• "MPECS -- A Flexible Machining Cell Controller," Wu, S.D. and Wysk, R.A., in Proceedings, IXth ICPR Conference, Cincinnati, OH, August 1987.
• "An Intelligent Flexible Machining Cell Controller," Wu, S.D. and Wysk, R.A., in Proceedings, European Simulation Multiconference , July, 1987.
• "A Multi-Pass Expert Control System for Flexible Manufacturing Systems," Wu, S.D., Wysk, R.A. and Yang, N.S., in Proceedings, The Symposium on Real-Time Optimization in Manufacturing Facilities, National Bureau of Standard, Gaithersburg, MD, January, 1986.
• "Physical and Graphical Modeling of Flexible Machining Systems," Ghosh, B.K., Wysk, R.A., Wu, S.D. and Cohen, R.H., in Proceedings of IIE Conference, Los Angeles, May 1985.

Game Theoretic Analysis and Distibuted Models

• "Supply Chain Intermediation: A Bargaining Theoretic Framework," S.D. Wu, (new, May 2004) click here to view the PDF document.
• "Managing High-Tech Capacity Expansion Via Reservation Contracts," M. Erkoc and S.D. Wu, (Updated August 2004) click here to view the PDF document.
• "Incentive Schemes for Semiconductor Capacity Allocation: A Game Theoretic Analysis," S. Karabuk and S.D. Wu, (updated August 2004), click here to view the PDF document.
• "Coordinating Supplier Competition via Auctions," M. Jin and S.D. Wu, (updated August 2004), click here to view the PDF document.
• "A Bargaining Game for Supply Chain Contracting," K. Ertogral and S.D. Wu, click here to view the PDF document. (updated August 2001)
• "Collaborative Resource Planning with Distibuted Agents ," E. Kutanoglu and S.D. Wu, (updated November 2001), click here to view the PDF document.
• "Procurement Auction with Supplier Coalitions: Validity Requirements and Mechanism Design," M. Jin and S.D. Wu, click here to view the PDF document. (Updated July 2002)
• "Due-Date Coordination in an Internal Market via Risk Sharing," M. Erkoc and S.D. Wu, click here to view the PDF document.
• "Decentralizing Semiconductor Capacity Planning via Internal Market Coordination," S. Karabuk and S.D. Wu, click here to view the PDF document.
• "Strategic Capacity Planning in the Semiconductor Industry" S. Karabuk and S. D. Wu, click here to view the PDF document.
• "An Incentive Compatible Mechanism for Distributed Resource Planning," E. Kutanoglu and S. D. Wu, click here to view the PDF document.
• "A Distributed Decision Framework Integrating Manufacturing Planning and Supply Chain Management" S.D. Wu and P.T. Harker, NSF Design and Manufacturing Grantees Conference, Monterrey, Mexico, January 1998.
• "Toward a Distributed Paradigm for Manufacturing Logistics," S. D. Wu and P. T. Harker, NSF Design and Manufacturing Grantees Conference, Long Beach, California, January 1999, click here to view the PDF document.
• "Auction-Theoretic Coordination of Production Planning in the Supply Chain," K. Ertogral and S.D. Wu, click here to view the PDF document.
• "On Combinatorial Auction and Lagrangean Relaxation for Distributed Resource Scheduling," E. Kutanoglu and S.D. Wu, IMSE Technical Report 97T-012, click to view the paper in PDF format
• "Improving Schedule Robustness via Stochastic Analysis and Dynamic Adaptation," E. Kutanoglu and S. D. Wu, IMSE Technical Reprot 98T-001, click to view the paper in PDF format
• "Ordinal Comparison of Heuristic Algorithms Using Stochastic Optimization", C.-H. Chen, S. D. Wu and L. Dai, IEEE Transactions on Robotics and Automation, forthcoming, click to view the paper in PDF format.
• "Integrating Production and Transportation Logistics in a Supply Chain Environment: A Lagrangean Decomposition Approach," K. Ertogral, S.D. Wu and L.I. Burke, IMSE Technical Report 98T-008, click to view the paper in PDF format.
• "A Multicommodity Flow Model for Manufacturing Planning Over Alternative Facilities," H. Golbasi and S.D. Wu, IMSE Technical Report 98T-004, 1998.
• "A Distributed Stochastic Optimization Model to Semiconductor Capacity Design, Configuration, and Allocation," S. Karabuk and S. D. Wu, manuscript under preparation.
• "Integration Production and Transportation in a Supply Chain via Negotiation and Bidding," K. Ertogral and S. D. Wu, manuscript under preparation

• Discrete and Combinatorial Optimazation

  Combinatorial Optimization

  "Optimization", S.D. Wu, in McGraw-Hill Yearbook of Science and Technology: 1994, McGraw-Hill, New York, 1994.
  "Ordinal Comparison of Heuristic Algorithms Using Stochastic Optimization," C.-H. Chen, S. D. Wu and L. Dai, IEEE Transactions on Robotics and Automation, click here to view the PDF document.
  An Incentive Compatible Mechanism for Distributed Resource Planning," E. Kutanoglu and S. D. Wu, click here to view the PDF document.

  Job Shop Scheduling (Problem Space Search)

• "Local Search in Problem and Heuristic Space for Job Shop Scheduling", Storer, R.H., Wu, S.D., and Vaccari, R., ORSA Journal on Computing, Vol.7, No.2, pp.453-467, 1996.
• "New Search Spaces for Sequencing Problems with Application to Job Shop Scheduling," Storer, R.H., Wu, S.D. and Vaccari, R., Management Science, Vol.38, No. 10, 1992, pp. 1495-1509.
• "Genetic Algorithms in Problem Space for Sequencing Problems", R.H. Storer, S.D. Wu, and I. Park, in Operations Research in Production Planning and Control, G. Fandel, T. Gulledge, and A. Jones (eds.), Springer-Verlag, 1993.
• "Local Search in Problem and Heuristic Space for Job Shop Scheduling Genetic Algorithms," Storer, R.H., Wu, S.D. and Vaccari, R., in New Directions for Operations Research in Manufacturing, T.Gulledge and A. Jones (eds), Springer- Verlag, 1991
• "Extensions of Problem Space in Job Shop Scheduling," I.-K. Park, S.D. Wu and R.H. Storer, Technical Report #94T-003, Dept. of Industrial Engineering, 1994.

Resource Constrained Project Scheduling

• "A Problem Space Search Method for the Resource Constraint Project Scheduling Problem," K. Naphade, S.D. Wu, and R.H. Storer; Annals of Operations Research, Special Volumn on Scheduling: Theory and Applications, Annals of Operations Research 70, Special Volume on Scheduling: Theory and Applications, 1997, pp. 307-326
• "Local Search in Problem Space for Resource Constrained Project Scheduling", I. Park, S.D. Wu, and R.H. Storer, ATLSS Technical Report No.94-02, 1994. 34. "Problem Space Search", I. Park, R.H. Storer, and S.D. Wu, ATLSS Technical Report No.94-03, 1994.

Other Combinatorial Problems

• "Problem Space Local Search for Number Partitioning", R.H. Storer, S.W. Flanders, and S.D. Wu, Annals of Operations Research 63, 1996, pp.465-487.
• "A Search Heuristic for Single Path and Bifurcated Routing in Wide Area Communication Networks," M.R. Bartolacci and S.D. Wu; Annals of Operations Research, Special Volumn on the Interface between Information Systems and Operations Research, under revision.
• "A Procurement Planning Model Integrating Strategic Planning with Dynamic Purchasing Decisions," Bonser, J. and S.D. Wu, Technical Report, Department of IMSE, Lehigh University.
• "Placement Problem in VLSI Design," I.-K. Park, R.H. Storer and S.D. Wu, Technical Report #94T-004, Dept. of Industrial Engineering, Lehigh University, 1994.