bluuebunny/crossref_metadata_2025 huggingface dataset:
Strategic and Operational Management with Optimization at Tata Steel
Authors: Sinha Gopal P. , Chandrasekaran B. S. , Mitter Niloy , Dutta Goutam , Singh Sudhir B. , Choudhury Aditya Roy , Roy P. N.
Published: October 2008

Tata Steel has been striving to optimize its operations amidst scarce resources and capacity imbalances. To provide decision support, we developed a mathematical model based on mixed-integer linear-programming (MILP) and hierarchical optimization between 1983 and 1986. It considers marketing constraints, capacities, yields, profitability, routes, energy, and oxygen balances. Its use just for optimal distribution of power has provided a benefit of US $73 million in the first year of implementation (1986–1987). Tata Steel has realized other benefits, such as optimal distribution of scarce oxygen and liquid iron, optimal power cogeneration levels, break-even prices and quantities of purchased scrap, and optimal conversion of semifinished steel into finished products by other companies functioning as conversion agents. In the early ’8Os, the model shifted Tata Steel’s emphasis from maximizing tonnage to maximizing contribution to profits.
Global Supply Chain Management at Digital Equipment Corporation
Authors: Arntzen Bruce C. , Brown Gerald G. , Harrison Terry P. , Trafton Linda L.
Published: October 2008

Digital Equipment Corporation evaluates global supply chain alternatives and determines worldwide manufacturing and distribution strategy, using the Global Supply Chain Model (GSCM) which recommends a production, distribution, and vendor network. GSCM minimizes cost or weighted cumulative production and distribution times or both subject to meeting estimated demand and restrictions on local content, offset trade, and joint capacity for multiple products, echelons, and time periods. Cost factors include fixed and variable production charges, inventory charges, distribution expenses via multiple modes, taxes, duties, and duty drawback. GSCM is a large mixed-integer linear program that incorporates a global, multi-product bill of materials for supply chains with arbitrary echelon structure and a comprehensive model of integrated global manufacturing and distribution decisions. The supply chain restructuring has saved over $100 million (US).
The Traffic-Control System on the Hanshin Expressway
Authors: Yoshino Tsuyoshi , Sasaki Tsuna , Hasegawa Toshiharu
Published: October 2008

In 1970, the Hanshin Expressway Public Corporation started operating an automated traffic control system to maximize the total traffic flowing into its expressway network. The corporation has been improving the system ever since. The system relies on two control methods. The first is to limit the cars coming onto the expressway at each entrance ramp to avoid congestion in any section. The system calculates the maximum allowable inflows by solving a linear programming problem once in every five minutes using data from detectors installed along the expressway and at all ramps. The second method is to give drivers the most recent and accurate traffic information about the expressway and its vicinity, including expected travel times and accidents, through various information channels so that they can decide what routes to take. This system is greatly appreciated by the corporation because it is extremely cost effective and also by drivers, who now consider it an indispensable service.
Consolidating and Dispatching Truck Shipments of Mobil Heavy Petroleum Products
Authors: Bausch Dan O. , Brown Gerald G. , Ronen David
Published: October 2008

Mobil Oil Corporation consolidates and dispatches truck shipments of heavy petroleum products—lubricants in packages and in bulk—from 10 lubricant plants nationwide. It dispatches hundreds of orders daily either individually or as consolidated truckloads, using a very nonhomogeneous fleet of Mobil-controlled and contract vehicles and common carriers. Shipment schedules may span several days and include stops to pick up returned drums or entire trailers. Shipping costs depend upon the vehicle used, the shipment size, the locations of the stops, and the route distance and time. Candidate consolidations are generated automatically or with dispatcher assistance. Then, the dispatcher uses optimization to select a minimal-cost set of schedules. Mobil has been using this system for three years, reducing annual transportation costs by about $1 million (US).
Misapplications Reviews: Jail Terms
Authors: Barnett Arnold
Published: October 2008

I have had several opportunities in recent months to serve as a statistical “expert” in judicial proceedings. Some people, of course, believe that such proceedings get even more incomprehensible and farcical as their quantitative content grows. But with regulations and requirements now routinely expressed in numerical terms, it is hard to see how statistics can be absent from accusations that the standards have been violated. And if one side in a case plays an absurd numbers game, then the other is as free to attack the analysis as it is to rebut any other form of evidence.
Creativity in MS/OR: Ten Exercises and the Number 24
Authors: Evans James R. , Pritsker A. Alan B.
Published: October 2008

In a previous column (Evans [Evans, James R. 1993. Creativity in MS/OR: The multiple dimensions of creativity. Interfaces 23(2) 80–83.]), I described some key traits that promote divergent thinking among creative individuals. These include awareness and problem sensitivity, fluency, flexibility, originality, and intellectual playfulness. Creativity can be enhanced by consciously trying to improve these traits. The two most important rules are to defer judgment and seek quantity (of ideas).
Lessons from an Early Management Scientist
Authors: Meyer Brad C.
Published: October 2008

Over 100 years ago, the silk industry in France was facing a serious threat. They called in an analyst, a “management scientist” if you will, named Louis Pasteur. Working with a small team, Pasteur critically studied the system to determine cause/effect relationships and the variables that management could control. He determined an optimal strategy and fought an uphill battle to win organizational approval. A setback occurred when he discovered that his model was invalid, not including an important factor. Pasteur persevered not only in the tedium of analysis, but also against jealous fellow scientists who sought to discredit his work. He was finally able to convince management by employing a variant of the now-popular technique of simulation. I have found this account from history a useful way to introduce the practice of management science to MBA students. The story shows (1) the usefulness of scientific analysis to business profitability; (2) the importance of observation skills, rigor, and critical thought; and (3) that there is more to management science than mathematics.
Managing Bank Productivity Using Data Envelopment Analysis (DEA)
Authors: Sherman H. David , Ladino George
Published: October 2008

One bank used data envelopment analysis (DEA) to substantially improve its branch productivity and profits while maintaining service quality. It identified over $6 million of annual expense savings not identifiable with traditional financial and operating ratio analysis in its 33-branch system. A fairly new linear-programming-based benchmarking technique, DEA explicitly considers all the resources each branch uses and the services it provides. It compares branches objectively to identify the best-practice branches, the less productive branches, and the changes the less productive branches need to make to reach the best-practice level and to improve their profitability.
The Paradigm of the Science of Management: In Celebration of C. W. Churchman’s 80th Birthday
Authors: van Gigch John P.
Published: October 2008

I explore C. W. Churchman’s philosophy of science to show his influence on the present-day paradigm of the science of management. I emphasize his seminal ideas concerning (a) the differentiation between the science of management and management science and (b) the resolution of dilemmas confronting the paradigm and discuss Churchman’s ideas on how the modern inquiring system—a system dedicated to the acquisition and production of knowledge and to the ethical solution of contemporary management problems—should be designed.
Completing the Loops
Authors: Denning Peter J. , Medina-Mora Raül
Published: October 2008

Total quality management (TQM) and business process reengineering (BPR) have emerged as important practices but not yet as a discipline. A methodology for mapping, measuring, tracking, and managing commitments in business processes is necessary to make a discipline from TQM and BPR. An organization’s network of commitments can be depicted as a map of interconnected work-flow loops. That map can be used as a guide to design work processes and their supporting information technologies, manage commitments to completion with customer satisfaction, and measure productivity. A study of a complex process, course scheduling, at George Mason University shows how the mapping notation and the method work.
Freight Routing and Scheduling at CSX Transportation
Authors: Huntley Christopher L. , Brown Donald E. , Sappington David E. , Markowicz Bernard P.
Published: October 2008

Two of a railroad’s fundamental tactical operations are routing shipments along its rails and scheduling trains necessary to service the routes. The computer-aided routing and scheduling system (CARS) bridges the gap between these day-to-day operations and strategic planning. By investigating low-cost routes and schedules in a controlled environment under various cost scenarios, CSX Transportation’s strategic planners can better account for these tactical operations in their long-range policies.
Quality Management at Kentucky Fried Chicken
Authors: Apte Uday M. , Reynolds Charles C.
Published: October 2008

Kentucky Fried Chicken (KFC) Corporation, a member of the quick-service restaurant industry, uses a sophisticated program to manage the quality of service it offers to its customers. In the last quarter of 1989, the south central division of KFC launched a test program in four Oklahoma City restaurants to improve the speed of service at its drive-through-window operation. It proved extremely successful. The restaurants cut service time by more than half while improving labor productivity. They also dramatically outperformed other restaurants in the division in profits, sales growth, and growth in customer transactions. The improved processes in the test restaurants have served as benchmarks for other KFC restaurants aiming for continuous process improvement, while the reduced service time now serves as the revised specification in KFC’s quality measurement and management program.
Services and Technology: Reengineering the Railroads
Authors: Harker Patrick T.
Published: October 2008

In the service-sector, productivity improvements due to technology investments are difficult to measure and document. Measuring productivity in this sector is problematic and many service-related technology investments have not generated major productivity gains. The railroad industry may be making such an investment. Advanced train control systems (ATCS) and their associated control algorithms have the potential to revolutionize this industry or to become yet another statistic in the low-productivity saga of services. One railroad’s experience with this technology highlights the need to carefully match the technology with the strategic direction of the firm and its services delivery processes and operations.
Undergraduate Business Statistics: A Survey of Topics and Teaching Methods
Authors: Strasser Sandra E. , Ozgur Ceyhun
Published: October 2008

Participants in the annual conferences on “Making statistics more effective in schools of business” have made recommendations for improving the teaching of statistics in schools of business. To determine what is being taught and how it is being taught in terms of these recommendations, we surveyed professors teaching undergraduate business statistics courses. We found that hypothesis testing receives the greatest share of coverage and quality control the least. Computers are not used in one quarter of the courses, and lecturing is still the dominant teaching method. When asked for a wish list of changes, professors most often listed greater use of computers and more relevant data.
Using Mathematical Programming to Help Supervisors Balance Workloads
Authors: Grandzol John R. , Traaen Thomas
Published: October 2008

As resources in the Department of Defense shrink, the Naval Aviation Supply Office must reduce the size of its organization, balancing work assignments fairly as it does. Having recently converted to Deming’s TQM principles, management assembled an employee involvement group to develop appropriate criteria for assigning work. Our introduction of management science techniques enabled this group to pursue its objectives. Using participative processes throughout, we applied mixed-integer programming to produce a model for repetitive use that all the participants own and understand. We utilized this model several times to mix types of work so that all participating employees received at least, and no more than, their fair shares.
Interdisciplinary Industry-University Collaboration: Lessons from an Operations Improvement Project
Authors: Balakrishnan Anantaram , Brown Stuart , Dunlap Duane , Pahl Robert
Published: October 2008

A six-month Leaders-for-Manufacturing student internship at the Alcoa extrusion and tube plant in Lafayette, Indiana identified a promising operations improvement opportunity in tube manufacturing and led to a two-year collaboration between Alcoa and faculty members from the schools of engineering and management at MIT to develop integrated process planning models. Project participants included production managers, supervisors and planners at the plant, process engineers from the Alcoa Technical Center, and faculty and students in engineering, operations research, and management. The project demonstrated that the plant could reduce tube drawing effort by more than 20 percent by using decision support tools and improving the planning processes. It also generated techniques to diagnose problems, new performance metrics, and software for short-term and medium-term process planning, persuaded plant managers to take a systems view of process planning, led to undergraduate and graduate thesis research, provided examples for class room use, and highlighted the enablers and challenges in conducting industry-university projects, particularly those dealing with supply-chain integration.
Thirty Years of Modeling Midair Collisions
Authors: Machol Robert E.
Published: October 2008

For 30 years, operations researchers have developed mathematical models of processes leading to possible collisions of aircraft flying in proximity to one another in order to estimate the risk of collision. These “collision risk models” were applied in the 1960s to determine safe separation standards between pairs of co-altitude aircraft on parallel courses over the North Atlantic Ocean. The models have been and are being continually refined and improved. They have been applied to different geographic regions (for example, the Pacific Ocean and domestic airspace), to different flight regimes (for example, high-altitude cruise and landing on closely spaced runways), and to different types of separation (vertical and longitudinal as well as lateral).
Integrated Planning for Poultry Production at Sadia
Authors: Taube-Netto Miguel
Published: October 2008

Sadia Concórdia SA, the largest poultry producer in Brazil, processing over 300 million chickens and 11 million turkeys a year, has increasingly used mathematical models since 1990 to improve decision making throughout its production chain. It has saved more than $50 million over a three-year period, as a result of (1) better conversion of feed to live bird weight; (2) improved utilization of birds to produce more than 300 products classified by weight range, taking into account weight variations between and within flocks; (3) almost 100 percent fulfillment of daily production plans with increased output of higher value products; (4) greater flexibility and reduced lead time in meeting market demand; and (5) timely and wide ranging studies of different price and demand scenarios. This original and pioneering use of operations research and management science approaches in the poultry industry is also adaptable to diverse production practices and applicable to other animal-processing industries.
IMPReSS: An Automated Production-Planning and Delivery-Quotation System at Harris Corporation—Semiconductor Sector
Authors: Leachman Robert C. , Benson Robert F. , Liu Chihwei , Raar Dale J.
Published: October 2008

IMPReSS, an optimization-based production planning system at Harris Corporation's semiconductor sector, generates capacity-feasible production schedules for a worldwide manufacturing network and quotes product delivery dates in response to customer inquiries. The planning engine of IMPReSS is the Berkeley Planning System (BPS), which models the problem in a form that permits linear programming optimization. BPS embeds formulation techniques for planning the requirements of binning and substitutable products, for representing dynamic capacity consumption by reentrant process flows, and for developing multiple optimization calculations that reflect marketing priorities. It uses a heuristic decomposition strategy to break the overall problem into several manageable calculations. Its implementation raised on-time deliveries of line items from 75 to 95 percent without increasing inventories, enabled the sector to expand its markets and its market share, and helped move the sector from a loss of $75 million to profit of over $40 million annually.
SQOM-2: The Israeli Air Force's Air Power Multiplier
Authors: Spector Yishay , Marom Leon
Published: October 2008

The major expense in the budget of any air force is its flight squadrons. A modern fighter squadron costs US $2 billion and consumes some US $100 million annually. The total investment in a fighter squadron over 25 years is some US $5 billion, and the cost of an average-sized air force is on the order of US $100 billion over this period. The Israel Air Force (IAF) estimated that these huge resources were not used properly in training and at times of crisis due to time-consuming manual management procedures at the squadron level and inefficient information updating in IAF headquarters and regions. In 1993, following successful installation and tests in two IAF squadrons, the IAF decided to install the SQOM-2 system in all IAF squadrons. With the system, squadrons executed 25 percent more sorties than squadrons without the system and increased accurate target hits by 17 percent, producing a 146-percent performance improvement. Operational management mistakes decreased by 30 percent and are moving towards zero.
Editorial: A Book About the Downside of New Technology
Authors: Rothkopf Michael H.
Published: October 2008

Editorial announcing a book review of the book “Silicon Snake Oil: Second Thoughts on the Information Highway” by Clifford Stoll.
Reducing Cycle Time at an IBM Wafer Fabrication Facility
Authors: Demeester Lieven , Tang Christopher S.
Published: October 2008

In 1991, IBM San Jose decided to produce and sell magnetic heads for computer disk drives on the open market to original equipment manufacturers. However, as IBM's wafer fabrication facility increased the number of products it manufactured, its manufacturing cycle time lengthened. Since cycle time is important in competing in the open market, IBM San Jose formed a study team (in cooperation with UCLA) to examine the wafer fab and to develop ways to reduce cycle time. The team designed a new production control system and proposed new performance measures for operators and engineers. IBM implemented the new production control system and established the performance measures in June 1992, and the cycle time decreased by 50 percent by the end of 1992.
Scheduling Coast Guard District Cutters
Authors: Brown Gerald G. , Dell Robert F. , Farmer Robert A.
Published: October 2008

United States Coast Guard (USCG) districts schedule cutters 180 feet or less in length to weekly statuses (statuses is USCG jargon for assignments) from which they primarily respond to calls for search and rescue, law enforcement, and pollution control. The First Coast Guard District, based in Boston, has one of the largest scheduling problems: Each of 16 cutters is assigned weekly to one of six statuses to ensure patrol coverage, enforce equitable distribution of patrols, and honor restrictions on consecutive cutter statuses. When we state this quarterly scheduling problem as an elastic mixed-integer linear program, we obtain face-valid schedules—superior to manually prepared schedules for all measures of effectiveness considered—within a few minutes on a personal computer. Initial acceptance of the model was hampered by disruptive schedule revisions that resulted from minor changes in input. Modifications to preserve run-to-run persistence of solutions have brought success.
Du Pont Uses a Decision Support System to Select Its Audit Portfolio
Authors: Lieb Eugene B. , Gillease Joanne K.
Published: October 2008

We designed a decision support system (DSS) to help select financial audit portfolios for E. I. Du Pont de Nemours and Company. Du Pont's finance department performs audits to ensure that financial control procedures are in place throughout the firm and that they are being followed. The system selects portfolios based on the potential risk of not auditing a specific auditable unit. Audit risk is based on the collective judgment of management. The DSS allows Du Pont to capture and merge individual opinions into a consensus and to select a sample portfolio. Using the audit decision support system, Du Pont reorganized its audit division, greatly reducing the resources required. The system has been in use since 1986 with virtually no programming maintenance.
Creativity in OR/MS: Creativity-Enhancing Strategies
Authors: Evans James R.
Published: October 2008

In previous columns, I discussed important attributes that creative individuals possess and the internal and external blocks that prevent one from being creative. In this column, I focus on some of the fundamental strategies and techniques for enhancing creativity. Hadamard notes that Henri Poincaré observed that unconscious work is not possible or even fruitful, unless it is first preceded and then followed by a period of conscious work. Conscious methods for creativity are intended to guide the formation and flow of ideas in the mind. They act as seeding vehicles to provide us with new insights, and they hasten the creative thinking process and help us to overcome obstacles to creativity by focusing our thoughts and energies.
MIMI/G: A Graphical Environment for Mathematical Programming and Modeling
Authors: Jones Chris , Baker Thomas E.
Published: October 2008

MIMI/G allows users to model their planning and scheduling problems graphically as well as textually. Users can view their models, data, and solutions as different types of graphs (networks). The graphical modeling capabilities are general enough to allow one to view and edit mathematical programs and expert system rules as graphs. MIMI/G has been successfully used by over 40 companies in 100 applications worldwide.
Personal Operations Research: Practicing OR on Ourselves
Authors: Lewis Tony
Published: October 2008

Documented cases of people applying OR in making personal decisions are hard to find. Standard OR models can be used to advantage in making personal and family decisions. In two examples, I used standard economic order quantity models to plan the size and timing of the transfer of funds to an overseas bank account. In a third case I used standard linear programming software to make financial plans to handle, in the best way, the problem of making regular household income cope with the lumpy nature of household bills. The benefits of producing a good financial plan for the family are partly monetary but are mostly in satisfaction gained and relief of stress.
People Skills: Using the Cooperative Learning Model to Teach Students “People Skills”
Authors: Fellers Jack W.
Published: October 2008

In his Interfaces article [1994], Robert Levasseur emphasized the need for and importance of “people skills” for students today. While Levasseur discussed the need for students to acquire such skills as interpersonal communication, group dynamics, and leadership, to take it the next step, faculty members need a means to provide students with these essential skills. One such means, the cooperative learning model, provides a way for students to learn “people (or process) skills” as they are learning the content material of their chosen field of study. Cooperative learning is based on structuring learning outcomes and experiences to promote student interaction and to improve student learning. Ultimately, faculty members must consider what knowledge, skills, and abilities students need and how to best prepare them for the changing workplace.
The Teachers' Forum: The Operations Analysis Curriculum at the Naval Postgraduate School
Authors: Washburn Alan
Published: October 2008

The operations analysis curriculum at the Naval Postgraduate School has responded to a variety of pressures for change in the 45 years since its founding, and its managers have continually wrestled with the theory-versus-practice question that has recently preoccupied ORSA/TIMS and INFORMS. Even though NPS is almost unique among graduate schools on account of its navy sponsorship, our experiences may still be of interest to others.
New Issues in Forest Land Management from an Operations Research Perspective
Authors: Weintraub Andrés , Bare B. Bruce
Published: October 2008

Over the last two decades, forest land management practices have changed in response to ecological issues and the need to improve efficiency to remain competitive in emerging global markets. Decision processes have become more open and complex as information and communication technologies change. The OR/MS community is meeting these challenges by developing new modeling strategies, algorithms, and solution procedures that address spatial requirements, multiresource planning, hierarchical systems, multiple objectives, and uncertainty as they pertain to both industrial timberlands and public forests.
What's the Problem? An Introduction to Problem Structuring Methods
Authors: Rosenhead Jonathan
Published: October 2008

OR's traditional problem-solving techniques offer remarkably little assistance in deciding what the problem is. New problem structuring methods (PSMs) provide decision makers with systematic help in identifying an agreed framework for their problem. The result is either a well-defined project that can be addressed using traditional OR methods, or a clarification of the situation that enables those responsible to agree on a course of action. In principle, PSMs can provide analysts with greater access to strategic problems—those engaging multiple relatively independent decision makers. PSMs' transparent methods of representation can capture differing perceptions of the situation, to help generate a consensus or to facilitate negotiations.
Finding the Yellow Brick Road: Part 2, Lions and Tigers and Bears!
Authors: Powell Warren B. , Mayoras Donald E.
Published: October 2008

Sometimes, there is more truth in fiction than in publicly available accounts. This story by Warren B. Powell, a leading researcher of real-time routing and scheduling models and frequent consultant to the motor carrier industry, and Donald E. Mayoras, a senior transportation executive and president of a trucking company, provides a view into the discussions many carriers undertake prior to adopting an optimization model. The account is too long to appear as a single article and instead is being published in serial form. This is the second installment.
Editorial: Models as Aids to Thought
Authors: Rothkopf Michael H.
Published: October 2008

The opening chapters of most good texts on operations research or management science discuss the approximate nature of models and the need for interaction between the modeler and the decision maker. Also, somewhere in the text is some discussion of sensitivity analysis. Nonetheless, the overall impression the texts give is that the models of our profession are directly applicable. While our models do contain important thinking, I believe that it is dangerous to treat them merely as embodiments of thought rather than as aids to further thought.
Modeling Crude Oil Lightering in Delaware Bay
Authors: Andrews Scott , Murphy Frederic H. , Wang Xiao Pei , Welch Steve
Published: October 2008

Crude oil destined for Philadelphia-area refineries is transferred to lighters from the tankers in Delaware Bay because the channel in the Delaware River is too shallow for fully loaded tankers. We developed a simulation model for studying the effects of various policies on service levels. The results were used by Maritrans, the provider of the lightering services, and its largest customer to examine ways in which they could improve their working relationship. Although the customer valued Maritrans' services, it was considering alternative lightering solutions and most seriously considering doing its own lightering. The results of the model provided a deeper understanding of the role of lightering in the customer's crude-oil logistics system, showing that acquiring a separate fleet would be costly and allowing both parties to evaluate other alternatives for reducing costs and improving response times.
A Consortium Sponsored Knowledge-Based System for Managerial Decision Making in Industrial Construction
Authors: Gupta Vipul K. , Fisher Deborah J. , Murtaza Mirza B.
Published: October 2008

Driven by economic and environmental considerations, a consortium of companies sponsored the development of a knowledge-based decision support system, called MODEX (Modularization Expert) to help professionals in the construction industry to make decisions about the feasibility of using modularization technology for construction projects. MODEX also provides a detailed analysis of the impact of modularization on the cost and schedule of the constructed facility. To acquire knowledge, we interviewed experts from 22 organizations including facility owners, contractors, and fabricators. Over 50 member companies of the consortium have evaluated and validated the system, and about 80 companies and universities in the US and other countries are now using it. By encouraging companies to use modules in building industrial plants, MODEX can help reduce the damage to the natural environment that results from heavy on-site construction activities.
Franz Edelman Award for Management Science Achievement
Authors: Finkelberg Howard , Graves Stephen C.
Published: October 2008

Editorial of the chairman of the 25th annual competition for the Franz Edelman Award for Management Science Achievement. The competition is sponsored jointly by INFORMS and its practice section, the College for the Practice of the Management Sciences (CPMS). The primary purpose of the competition is to recognize outstanding accomplishments in the practice of management science. The prizes recognize verifiable results that had a major impact on the client organization. The award is named in honor of Franz Edelman. Dr. Edelman was responsible for management sciences at RCA, one of the earliest industrial OR/MS activities in North America. He worked for 30 years at RCA and is counted among the fathers of innovation in management science.
Absolutely, Positively Operations Research: The Federal Express Story
Authors: Mason Richard O. , McKenney James L. , Carlson Walter , Copeland Duncan
Published: October 2008

Federal Express Corporation has used operations research (OR) to help make its major business decisions since its overnight package delivery operations began in 1973. An early failure pointed out the need for scientific analysis. Subsequently, a successful origin-destination model followed by models to simulate operations, finances, engine use, personal assignments, and route structures influenced the conduct of business during periods of substantial growth. There were many false starts between the successes. CEO and founder Frederick W. Smith played a central role in the use of OR at the company: he established a relationship with OR and management science personnel and this relationship supported the growth and success of the company.
The Shuttle by United
Authors: Kimes Sheryl E. , Young Franklin S.
Published: October 2008

United Airlines designed the Shuttle by United to compete in the short-haul air service market. Up to mid-1994, United had been steadily losing market share in the short-haul markets to new carriers with lower costs. It seized an opportunity created by an employee buyout through an employee stock ownership plan (ESOP) to reestablish itself as a competitor in those markets. Using a combination of market research, employee teams, and process analysis, United reduced its costs by 30 percent, increased plane utilization, and cut turnaround time in half from its existing air service. Its efforts have resulted in higher customer satisfaction, improved market share, reduced costs, and increased profitability.
The Cost of Regulation
Authors: Littrell Earl , Thompson Fred
Published: October 2008

Advocates of regulatory benefit-cost analysis are right in theory, albeit somewhat impractical. In a sense, they have put the cart before the horse. Right now we cannot satisfactorily estimate the costs of government regulation, let alone its benefits. We must understand what drives cost before we can make satisfactory cost estimates. But, first of all, we need good cost measures to figure out what drives cost. We don't now measure the costs of regulation. Accurate measurement of the cost of regulation is, therefore, the first step to better regulatory practice. This means accounting for the regulatory burdens on firms and subordinate governments and allocating those burdens to the regulatory policies that induced them.
Evaluating Future Military Space Technologies
Authors: Burk Roger C. , Parnell Gregory S.
Published: October 2008

In a major Air Force study of future space systems, SPACECAST 2020, study teams produced a set of system concepts for 21st century military space operations. Our goal was to assess the potential operational utility of these systems in an objective, traceable, and robust manner, so that we could compare the systems and identify the most important. An additional goal was to determine the technologies whose advancement will do the most to make the high-priority systems a reality. To do this, we developed a hierarchical value model based on Department of Defense policy documents and the operational judgments of Air University faculty and students (senior and mid-level managers who will be future Air Force leaders). We completed the study within an extremely tight deadline, and it was widely accepted within the Air Force.
Learning the Practice of Operations Research
Authors: Eaves B. Curtis
Published: October 2008

The OR department at Stanford University has made a 20-year effort to develop an environment for learning the practice of OR. The first of two courses is based on student teams competing to improve existing case results, and the second course is based on student teams undertaking sponsored projects in industry.
Estimating and Projecting Regional HIV/AIDS Cases and Costs, 1990–2000: A Case Study
Authors: Harris Carl M. , Rattner Edward
Published: October 2008

We developed predictions of HIV/AIDS caseloads and costs for the Northern Virginia Planning District Commission as input to its continuing evaluation of the economic welfare of northern Virginia's cities and counties. We developed a series of procedures beginning with US case and cost estimates for the period 1990 to 2000 and leading to estimates of state and local HIV/AIDS cases and costs. As a result, we estimate that the annual incidence of AIDS in northern Virginia will increase from 391 in 1990 to 643 by 2000, while pre-AIDS prevalence will decline from a peak of about 6,900 in 1993 to about 4,400 in 2000. We estimate the medical costs to the region of AIDS (excluding pre-AIDS cases) will reach $65 million annually (1992 $) by the turn of the century.
Creativity in OR/MS: The Creative Problem-Solving Process, Part 1
Authors: Evans James R.
Published: October 2008

Over the years, Gene Woolsey and others have taught us that mathematics and models are not always necessary to solve important problems in OR/MS. Often the best solutions are novel and unusual—that is, they are creative. The principles of creative thinking can help practitioners and researchers in OR/MS explain, understand, and enhance their work. In this series of columns, I discuss many principles of creative thinking and ways in which you can become more creative and enhance your problem-solving skills. I invite you to submit your examples, comments, and perspectives on creativity.
Locating and Sizing Plants for Bottling Propane in South India
Authors: Sankaran Jayaram K. , Raghavan N. R. Srinivasa
Published: October 2008

Shri Shakti LPG Ltd. (SSLPG) imports and markets propane (referred to as liquefied petroleum gas (LPG) in India) in south India. It sells LPG in packed (cylinder) form to domestic customers and commercial establishments through a network of dealers. Dealers replenish their stocks of filled cylinders from bottling plants, which in turn receive LPG in bulk from the cheaper of SSLPG's two import-and-storage facilities that are located on the Indian coast. We implemented integer programming to help SSLPG decide on the locations and long-run sizes of its bottling plants. We estimate that our recommended configuration of bottling plants is about $1 million cheaper annually than the one that SSLPG had initially planned.
Managerial Relevance: The Key to Survival for OR/MS
Authors: Carraway Robert L. , Clyman Dana R.
Published: October 2008

OR/MS has come under increasing pressure within the MBA community to justify its place in the curriculum. Bucking this trend, Darden's first-year OR/MS course, “Quantitative analysis” (QA), is routinely rated by students as one of the top courses in the required core of the MBA curriculum. We believe the course's success is due largely to its focus on managerial relevance, rather than operations research, management science, statistics, or any other methodological discipline, per se. By managerial relevance, we mean that our modules and individual classes have a decision-oriented focus, raise issues and address contexts pertinent to the informed business person, and integrate closely with functional courses like finance, marketing, and operations. We contend that managerial relevance depends less on the macro-level course design than on the details at the class- and module-design levels.
Optimal Investment Policies for Pollution Control in the Copper Industry
Authors: Mondschein Susana V. , Schilkrut Ariel
Published: October 2008

We developed a decision-support system for investment projects in pollution abatement plants at state-owned copper smelters in Chile. We formulated a mixed-integer linear model to determine the optimal investment policy for this interrelated production-environmental problem. Because of the significant differences between the model's solutions and the initial clean-up plans the smelters submitted to the environmental authorities, the government has revised the smelters' clean-up plans, initially working to obtain more complete and reliable information. Furthermore, it has put some of the projects presented in the original clean-up plans on hold until it has a refined version of the model. The Chilean budget director has approved other clean-up plans because, as the director of policy planning at Cochilco said, they are consistent with the model's recommendations.
An Assessment of Tritium Supply Alternatives in Support of the US Nuclear Weapons Stockpile
Authors: von Winterfeldt Detlof , Schweitzer Eric
Published: October 2008

Nuclear weapons require the periodic replacement of tritium, a radioactive gas that decays at approximately 5.5 percent per year. Currently no tritium-supply facility exists in the US, and due to the decay, the tritium inventory will fall below the required reserve level in 2011. To decide how to fill this projected gap, the US Department of Energy assessed 10 tritium-supply alternatives, including several types of new reactors, an accelerator, and the use of commercial reactors. The DOE compared the alternatives with respect to three objectives: production assurance, cost, and environmental impacts. We combined a dynamic production-simulation model and probabilistic assessments of schedule, production capacity, and availability risks to predict the production behavior of each alternative over 40 years. We also assessed the cost and environmental risks. The secretary of energy decided to pursue both the commercial-reactor and accelerator alternatives, based, in part, on the results of this analysis.
Modeling the Impacts of the 1990 Clean Air Act Amendments
Authors: Luong Thanh , Murphy Frederic H. , Sanders Reginald , Holte Susan H. , Whitman Peter
Published: October 2008

The Clean Air Act Amendments of 1990 changed the regulations for air pollution by replacing a set of mandated actions with a market mechanism for pollution rights, where electric utilities can buy or sell rights to emit sulphur dioxide (SO2). We implemented the provisions related to the reduction in SO2 in the National Energy Modeling System (NEMS) to assess their impacts on energy markets. Because of the decentralized design of NEMS, the implementation was quite complex. We had to use Lagrangian relaxation, which turned out to be more difficult than first envisioned, and other techniques to arrive at a consistent equilibrium among the relevant energy sectors. As a result of these difficulties, we revised the NEMS model. This exercise illustrates that often an organization should be ready to take a step back from what exists to take a step forward.
Teaching Operations Research: Lessons from Cognitive Psychology
Authors: Liebman Judith S.
Published: October 2008

Instructors increase their students' understanding and retention of knowledge by creating more opportunities for active learning. According to cognitive psychologists, instructors should design learning activities according to the type and difficulty of the specific knowledge to be learned. Ten cognitive strategies, related to three types of knowledge, can be used to generate active learning.
A Hierarchical Approach to Managing Dairy Routing
Authors: Adenso-Díaz Belarmino , González Mónica , García Emérita
Published: October 2008

We designed and implemented a decision support system to organize the delivery network for the products of a large dairy. To deal with this complex problem, we employed a five-level hierarchic structure distributing the clients among the sales promoters in the levels of greater aggregation and assigning shops to individual drivers in the level with the greatest detail, which corresponds to a version of the traveling salesman problem with time windows. We implemented the model on a microcomputer, importing the necessary data from the company mainframe.
Simulating the Control of a Heterosexual HIV Epidemic in a Severely Affected East African City
Authors: Bernstein Robert S. , Sokal David C. , Seitz Steven T. , Auvert Bertran , Stover John , Naamara Warren
Published: October 2008

We compared three intervention strategies for preventing heterosexual transmission of the human immunodeficiency virus (HIV) using deterministic and stochastic models to simulate the epidemic of acquired immunodeficiency syndromes (AIDS). We estimated demographic, biological, and behavioral parameters for a severely affected east African city early in the epidemic, and used these parameter values in computing the spread of HIV under five scenarios: (1) a baseline scenario with no public health interventions; three single-intervention scenarios with strategies to (2) reduce the number and rate of change of sex partners, (3) increase condom use, or (4) improve treatment of sexually transmitted diseases (STD); and a (5) combined-intervention scenario. The rankings were the same in both models—decreasing partner change was most effective, followed by condom use and STD treatment. Combined interventions were more effective than single interventions. They interacted to produce impacts that varied with the trajectory of the epidemic at the onset of the interventions. Their timely, targeted, and sustained implementation appears critical to slow the epidemic significantly.
A Dynamic HIV-Transmission Model for Evaluating the Costs and Benefits of Vaccine Programs
Authors: Edwards Donna M. , Shachter Ross D. , Owens Douglas K.
Published: October 2008

We developed a dynamic model of HIV transmission to evaluate the costs and benefits of HIV-vaccine programs in a population of homosexual men. We examined how changes in high-risk sexual behavior and the growth pattern of the epidemic influence the cost-effectiveness of preventive vaccines and of therapeutic vaccines. We found that the effect of reductions in condom use is more important for therapeutic vaccines than for preventive vaccines. Therapeutic vaccines may increase HIV seroprevalence in the population, unless the vaccine program is accompanied by increased condom use. Epidemic growth patterns also influence the cost-effectiveness of both vaccines, but the effects are more pronounced for preventive vaccines, which are more cost-effective in an early-stage epidemic than in a late-stage epidemic.
Designing HIV Vaccination Policies: Subtypes and Cross-Immunity
Authors: Porco Travis C. , Blower Sally M.
Published: October 2008

We developed and used mathematical models to assess vaccine programs for controlling two subtypes of HIV, both for developing countries where more than one subtype is present and for countries where only one subtype is present but other subtypes may invade. We began by formulating a model of the intrinsic transmission dynamics of the two HIV subtypes and then extended this model to include the effects of a prophylactic vaccine that provides a degree of protection against infection by one subtype and vaccine-induced cross-immunity against infection by the second subtype. Using these models, we assessed the potential impact of using a prophylactic vaccine when one subtype of HIV is endemic and a second subtype is introduced into the community. In each case, mass vaccination could result in one of four possible outcomes: (1) both subtypes are eradicated, (2) the endemic subtype persists and the invading subtype is eradicated, (3) the endemic subtype is eradicated and the invading subtype persists, or (4) both subtypes coexist.
Planning Home Assistance for AIDS Patients in the City of Rome, Italy
Authors: De Angelis V.
Published: October 2008

In allocating resources to health-care services, the main difficulties derive from uncertainty concerning the number of patients who need the service and the level of care required by each patient who is entitled to receive it. I deal with the problem of allocating resources to the home-care service provided to AIDS patients in the city of Rome, Italy, which include medical assistance provided by nurses and doctors and social assistance and accompaniment of patients provided by social workers. A simple linear programming model solves the problem for single organizations, which provide assistance within a given budget, and for public-health authorities, which have to evaluate the results of tentative budgets assigned to home care.