Business and Engineering Networks

Enterprise Networks

Mission

The Enterprise Networks team studies manufacturing and service systems from the perspectives of efficiency, robustness and complexity. The overarching goal is to identify better methods of design, control and management of the networks used to deliver goods and services to customers. Researchers in the group make use of optimization, stochastic modeling, simulation, network flow models, economics, decision theory, statistics, and other tools to model and analyze value chain networks. Because these systems are complex and multi-dimensional, members of the Enterprise Networks group frequently collaborate with colleagues in the behavioral, managerial and engineering sciences.

Samples of Current Research Projects

Physics of the Cycle Time-Throughput Relationship in Semiconductor Manufacturing (Ankenman, Nelson): This research develops cycle time-throughput curves to represent the production physics of complex wafer fabrication facilities by fitting parametric models to large-scale computer simulations of the fab. The approach combines queueing theory, stochastic simulation and sequential experiment design. (Funded by NSF and Semiconductor Research Corporation)

Supply Chain Design for Risk Mitigation (Daskin, Chopra, Coullard): The goal of this research is to design supply chains so that they are robust with respect to a variety of risks including the risk of significant disruptions in parts of the chain. Such disruptions can be due to natural disasters, terrorist incidents or business failures. The stochastic nature of the disruptions, coupled with the interconnected nature of the flows makes the system inherently complex. (Funded by NSF and GM).

Principles Based Knowledge Management (Hopp, Iravani, Birnbaum): This research is making use of the principles of factory physics to organize and use information in a firm's intranet to diagnose and improve the performance of manufacturing cells. The approach being used combines decision trees with context based search methods to help a decision maker both ask the right questions and find the right information to solve a specific problem. (Funded by NSF and Motorola)

Principles of White Collar Workforce Management (Hopp, Iravani, Uzzi): This research is seeking to identify fundamental principles governing the productivity and effectiveness of professional work, such as sales and engineering. Because such work is collaborative and involves creativity, the modeling framework being used is based on social network representations of organizational communication. (Funded by NSF and GM)

Flexibility in Production and Service Operations Systems (Iravani and Van Oyen): This research is making use of the theory of complex networks along with optimization models to study how flexible resources (e.g., multi-functional machines, agile workforce) contribute to the flexibility of an enterprise. The objective is to develop a set of rules and principles that help managers in their strategic decision of how to make the best use of their resources. (Funded by NSF)

Convergent Optimization via Most-Promising-Area Stochastic Search (COMPASS) (Nelson): This research develops a framework within which the performance of complex, stochastic systems can be optimized when the system is represented by a computer simulation. COMPASS uses highly adaptive random search to achieve convergence when the controllable decision variables are discrete. (Funded by NSF)

Design principles for effective transshipment networks (Smilowitz-Corr and Iravani): The objective of the proposed research is to establish basic principles of and guidelines for design for effective transshipment networks. In these networks, inventory is moved among many locations within a supply chain. Transshipment networks can achieve the benefits of risk pooling while maintaining low inventory levels at individual locations, reducing supply chain costs and improving responsiveness.

Coordination of Drayage Operations (Smilowitz-Corr and Ziliaskopoulos): This research is developing strategies to intelligently coordinate the movement of trailers and containers, with a focus on the Chicago freight interchange, a region unique in its size and complexity of operations. (Funded by NSF)

Directors

Sunil Chopra, MEDS, Kellogg
Email: s-chopra@northwestern.edu
http://www.kellogg.northwestern.edu/faculty/bio/Chopra.htm

Wallace Hopp, IEMS, McCormick
Email: hopp@northwestern.edu
http://users.iems.northwestern.edu/~hopp/

Board

Advisory Board of MMM Program

Affiliated Faculty

Philipp Afeche
Email: p-afeche@northwestern.edu
www.kellogg.northwestern.edu/faculty/bio/afeche.htm
Research Interests: design of service systems, supply chain management, economics of information systems and communication networks

Bruce Ankenman
Email: ankenman@iems.northwestern.edu
http://users.iems.nwu.edu/~bea/
Research Interests: quality engineering, design of experiments

Daniel Apley
Email: apley@iems.northwestern.edu
http://users.iems.nwu.edu/~apley
Research Interests: manufacturing control, quality management

Baris Ata
Email: b-ata@kellogg.northwestern.edu
www.kellogg.northwestern.edu/faculty/bio/ata.htm
Research Interests: dynamic control of manufacturing systems and communication networks: heavy traffic approximations, Brownian and fluid network models, discrete-review policies, and analysis of asymptotic performance; power control in wireless communication; revenue management

Sunil Chopra
Email: s-chopra@northwestern.edu
www.kellogg.northwestern.edu/faculty/bio/Chopra.htm
Research Interests: integer programming, design of communication systems, design of distribution systems, supply chain robustness

James Conley
Email: j-conleya@kellogg.northwestern.edu
www.kellogg.northwestern.edu/faculty/bio/conley.htm
Research Interests: management of intellectual property; rapid product development methods for consumer durables

Mark Daskin
Email: daskin@iems.northwestern.edu
http://users.iems.nwu.edu/~msdaskin/
Research Interests: facility location; transportation planning; scenario based risk management

Sudhakar Deshmukh
Email: s-deshmukh@northwestern.edu
www.kellogg.northwestern.edu/faculty/bio/deshmukh.htm
Research Interests: probabilistic and stochastic optimization models of decisions involving time and uncertainty, with applications in operations management, management science, and economics

Wallace Hopp
Email: hopp@northwestern.edu
http://users.iems.northwestern.edu/~hopp/
Research Interests: knowledge management; manufacturing management; product innovation; social networks; stochastic optimization;

Tito Homem-de-Mello
Email: tito@northwestern.edu
http://users.iems.northwestern.edu/%7Etito/
Research Interests: revenue management, simulation, stochastic optimization

Seyed Iravani
Email: iravani@iems.northwestern.edu
http://users.iems.northwestern.edu/~iravani/
Research Interests: optimization of queueing systems; workforce agility in production and service operations systems; stochastic scheduling; analysis of integrated production and maintenance policies in manufacturing systems with limited repair or setup capacity; design and analysis of supply chains with information sharing

Martin Lariviere
Email: m-lariviere@kellogg.northwestern.edu
www.kellogg.northwestern.edu/faculty/bio/lariv.htm
Research Interests: economics of operations management, incentives in operations, supply chain management and contracting, and the marketing-manufacturing interface

Barry Nelson
Email: nelson@iems.northwestern.edu
http://users.iems.nwu.edu/~nelsonb/
Research Interests: computer simulation of stochastic systems, stochastic processes, statistics

Sharon Novak
Email: s-novak@kellogg.northwestern.edu
www.kellogg.northwestern.edu/faculty/bio/novak.htm
Research Interests: analysis and management of supply chains. Specific research focuses on the interaction between product development and the make/buy decision in affecting the transaction costs faced by the firm

Canan Savaskan
Email: r-savaskan@kellogg.northwestern.edu
www.kellogg.northwestern.edu/faculty/bio/savaskan.htm
Research Interests: incentive, channel design and coordination issues in supply chain management; specific focus on product take-back and remanufacturing systems; analysis and modeling of interaction between manufacturing and marketing decisions

Karen Smilowitz-Corr
Email: ksmilowitz@iems.northwestern.edu
http://users.iems.northwestern.edu/%7Esmilo/
Research Interests: design of large scale logistics systems, infrastructure management, transportation

Jan Van Mieghem
Email: vanmieghem@kellogg.northwestern.edu
www.kellogg.northwestern.edu/faculty/bio/vanmiegh.htm
Research Interests: analysis and management of business processes that deliver goods and services. Specific research focuses on management and investment under uncertainty, such as pricing and dynamic control of stochastic processing networks

Rakesh Vohra
Email: r-vohra@northwestern.edu
www.kellogg.northwestern.edu/faculty/bio/vohra.htm
Research Interests: auction theory, combinatorial optimization

Social Organizations and Communication Technology

Mission

Transportation systems are complex network systems that integrate the economy and society, providing accessibility to places and mobility to people and goods. Transportation is a key determinant of the location of activities and people, and of the success and satisfaction of people and organizations. It has a major influence on resource consumption and environmental quality. Planning and management of transportation systems is essential to assuring their viability, effectiveness and efficiency in the long run to support social and economic development, and in the short run to respond to daily variations in travel demand as well unexpected disruptions in system performance.

Transportation networks are managed by a variety of interacting agents (e.g., government agencies and private firms) at different levels. The location of activities and the movements that occur on transportation networks are primarily user-determined, driven by individual objectives. The functioning of transportation systems is determined by the interaction of atomistic behavior of individuals, decisions made by the network managers and operators, and the characteristics and operations of technology-based systems.

Understanding and predicting the functioning of transportation systems, necessary for system management and planning, requires knowledge of both individual and organizational behavior and principles of network operations and control. Research in this field is directed toward understanding, developing and operating transportation systems in time and space to meet broad sets of goals and objectives.

Northwestern's transportation research community blends three capabilities:

• Network modeling for long term planning and design as well as short term operational control.
• Travel and location behavior modeling to anticipate traveler and shipper response to short- and long-term changes in accessibility, service quality, and prices.
• Policy analysis to provide decision support for managers responsible for network investments and system operations.

Faculty

Sunil Chopra, Managerial Economics and Decision Sciences

Mark S. Daskin, Industrial Engineering and Management Sciences

Pablo Durango-Cohen, Civil and Environmental Engineering

Tito Homem-de-Mello, Industrial Engineering and Management Sciences

Joel Horowitz, Economics

Frank S. Koppelman, Civil and Environmental Engineering

Barry L. Nelson, Industrial Engineering and Management Sciences

Joseph L. Schofer, Civil and Environmental Engineering

Karen R. Smilowitz-Corr, Industrial Engineering and Management Sciences

Athanasios Ziliaskopoulos, Civil and Environmental Engineering