bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Comparison of Constraint and Mixed-Integer Programming Solvers for Batch Sequencing with Sequence-Dependent Setups
Authors: Jordan Carsten , Drexl Andreas 
Published: October 2008

A batch sequencing model with sequence-dependent setup-times and -costs is used to compare modeling and solving with two different general solvers. “Conceptual models” are implemented and solved using the constraint programming language CHARME. The mixed-integer-programming (MIP) formulation of the same problem is solved with OSL, a state-of-the-art MIP solver. We compare modeling in both solvers and the performance of the constraint versus the mixed-integer programming solver. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
Introduction to the Cluster on Knowledge and Data Management
Authors: Basu Amit 
Published: October 2008

The design and analysis of efficient database management systems (DBMSs) and knowledge based systems (KBSs) is an important research area where operations research (OR) methods such as mathematical programming, stochastic modeling, and simulation have a significant role to play. To appreciate this, consider that although relational database technology is about 25 years old, it is only in the last 5 to 10 years that large organizations have started adopting relational DBMSs for critical applications, primarily because of concerns about the efficiency of relational systems. Mathematical programming models that address the significant costs of data processing, and permit OR-based performance analysis of DBMSs, are essential for making the technology more acceptable and reliable. Similarly, relatively few organizations today use KBSs for domains where the knowledge bases are large, or where response time is critical. As with DBMSs, the primary constraint is efficiency and reliability. OR methods for optimization can be used to improve the performance of these systems, and OR methods for performance analysis can help answer critical questions about their efficiency and reliability. The articles in this cluster present interesting examples of the use of OR in data and knowledge management. The articles address issues ranging from established ones such as distributed database design, query optimization, and rule processing to emerging areas such as main memory databases. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
A Stochastic Model for Performance Evaluation of Main Memory Resident Database Systems
Authors: Goes Paulo B. 
Published: October 2008

With the rapid evolution in the computer industry where memory chips of increasing capacity are introduced every year at lower costs coupled with the increasing demand for massive on-line databases, a great deal of research has been done in the area of main memory resident databases. The use of these systems can achieve significant performance improvements in environments with very high volume of transactions by eliminating the need for most I/O functions while performing basic database operations. A primary concern in such systems is how to develop efficient recovery mechanisms to cope with system failures that can erase the contents of the main memory. This paper presents a stochastic model to evaluate the performance of the database system in terms of normal operation, checkpointing and recovery from system failures. Through a multi-variate model important transform results of effective residence times in each of the database states are derived, which allows the computation of first moments of interest, ergodic state probabilities, including the system availability, and reward measures. The model developed in the paper is significantly more general than previous stochastic models for traditional databases thus capturing the special features of recovery of main memory systems. The applicability of the model is supported and verified through numerical experiments. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
A Relationship Between CNF and DNF Systems Derivable from Examples
Authors: Triantaphyllou Evangelos , Soyster Allen L. 
Published: October 2008

In learning from examples, the main goal is to use a collection of positive examples and a collection of negative examples to derive a Boolean expression which satisfies the requirements imposed by the examples. In order to represent such a Boolean expression, the conjunctive normal form (CNF) and the disjunctive normal form (DNF) have been proposed. This paper makes two contributions. First it shows how to use any DNF algorithm to derive a CNF formula (or vice-versa). Furthermore, it demonstrates how to make efficient use of DNF algorithms which cannot handle a large number of positive (or negative) examples by using them as negative (or positive) examples and deriving CNF (or vice-versa). Therefore, the findings of this paper can be used to solve efficiently large scale learning problems. Two learning algorithms are used to illustrate the above issues. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
A Graph Theory-Based Approach for Partitioning Knowledge Bases
Authors: Srikanth Rajan 
Published: October 2008

The growing interest in using structured methodologies for design and development is a clear signal of the maturation of knowledge-based systems technology. The objective of this paper is to explore “modularization”—one of the cardinal principles of good design—as it applies to knowledge-based systems. Drawing upon the fact that graphs have routinely been used to pictorially depict different approaches to knowledge representation, this paper argues that the problem of modularizing a knowledge base corresponds to one of decomposing its equivalent graph with nodes depicting objects/frames/rules, and edges depicting relationships between them. The problem of finding cohesive, minimally coupled decompositions of this graph is made particularly interesting because it is not meaningful to assign cardinal weights to the labelled edges (or relationships) for minimum cost partitioning, and difficult to assess the similarity of different nodes (or objects/frames/rules) for purposes of clustering. A lexicographic ordering of edge types can however be, and often is specified, as are structural properties for each of the subgraphs. The paper proposes a formulation of the decomposition problem as one of partitioning the graph of a knowledge base using a “pseudo-cost” construct that ensures internal structural properties of subgraphs while operationalizing lexicographic priority in the placement of partition boundaries. It also demonstrates how a heuristic algorithm for partitioning knowledge bases can be developed by using this construct and appropriately adapting any of the procedures currently available for minimum cost graph partitioning. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
A Staged Primal-Dual Algorithm for Perfect b-Matching with Edge Capacities
Authors: Miller Donald L. , Pekny Joseph F. 
Published: October 2008

We describe an algorithm for finding a minimum cost perfect b-matching in a weighted undirected graph G=(V,E), with arbitrary edge capacities. The algorithm is based on a staged approach that sequentially applies increasingly more expensive steps until a solution is found. The most significant step involves a primal-dual tree growth procedure that selectively activates and deactivates facet inducing blossom constraints. The algorithm progressively eliminates half-integral values from the primal solution without creating any new fractional values. We introduce the concept of frozen supervertices to address previously unknown complications that arise due to the presence of non-unit capacity edges. We discuss the relationship of the algorithm to previously published cutting plane methods. The algorithm is guaranteed to terminate in O(|V|2|E|) steps, although computational results suggest that much less effort is typically required. Computational results show the algorithm to be effective on problems derived from TSPLIB ranging in size from 532 to 3795 vertices for various b values. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
Parallel Algorithms for Stochastic Dynamic Programming with Continuous State and Control Variables
Authors: Eschenbach Elizabeth A. , Shoemaker Christine A. , Caffey Hugh M. 
Published: October 2008

We compare two partitioning methods for solving a multi-dimensional optimal control problem in parallel using continuous state, continuous control, stochastic dynamic programming (SCP). The algorithm uses tensor products to interpolate the multi-dimensional, continuous variable state space. Unlike previous parallel SDP applications, an iterative optimization routine is used to find the optimal continuous control for each node point in the state space. This routine causes load balance and dependence problems not encountered in previous parallel SDP applications. Even with these additional computational complexities, superb efficiencies are achieved on a shared memory MIMD architecture. The two methods of solution differ in the following way: Method 1 uses the outer state loop index to send subsets of the state space (called parcels) to each concurrent process. The number of parcels sent as parallel tasks is the number of discretizations of one of the state variables. Method 2 allows the user to determine the number of parcels to be sent as parallel tasks. Method 2 splits the state space into a greater number of parcels, so that the processors are more likely to finish at the same time at a synchronization barrier. Computational results indicate that Method 2 has better load balance, with efficiencies up to 93.5%. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
Tabu Thresholding: Improved Search by Nonmonotonic Trajectories
Authors: Glover Fred 
Published: October 2008

There is an appeal to methods like simulated annealing and threshold acceptance that operate by imposing a monotonically declining ceiling on objective function levels or degrees of disimprovement (treated probabilistically or deterministically). An alternative framework, embodied in tabu search, instead advocates a nonmonotonic form of control, keyed not only to the objective function but to other elements such as values of variables, direction of search, and levels of feasibility and infeasibility. This creates a more flexible search behavior and joins naturally with the use of memory-based strategies that are the hallmark of tabu search approaches. Embodied particularly in the strategic oscillation component of tabu search, this nonmonotonic control has been shown in a variety of studies to yield outcomes superior to those of simulated annealing and threshold acceptance. The question arises whether such an approach offers a sufficiently rich source of search trajectories to be relied upon as a primary guidance mechanism, with greatly reduced reliance on forms of memory customarily used in tabu search. To provide an easily implemented method of this type we propose a tabu thresholding approach, which joins prescriptions of strategic oscillation with a candidate list procedure derived from network optimization studies. The candidate list and tabu search philosophies are mutually reinforcing, and the computational advantages contributed by these elements, documented by studies cited in this paper, motivate a closer look at combining them. The result yields a method with a significant potential for variation and an ability to take advantage of special structure. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
Problem and Heuristic Space Search Strategies for Job Shop Scheduling
Authors: Storer Robert H. , Wu S. David , Vaccari Renzo 
Published: October 2008

In a recent paper we discussed “problem” and “heuristic” spaces which serve as a basis for local search in job shop scheduling problems. By encoding schedules as heuristic, problem pairs (H,P) search spaces can be defined by perturbing problem data and/or heuristic parameters. In this paper we attempt to determined, through computational testing, how these spaces can be successfully searched. Well known local search strategies are applied in problem and heuristic space and compared to Shifting Bottleneck heuristics, and to probabilistic dispatching methods. An interesting result is the good performance of genetic algorithms in problem space. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
A Study of the Augmented System and Column-Splitting Approaches for Solving Two-Stage Stochastic Linear Programs by Interior-Point Methods
Authors: Czyzyk Joseph , Fourer Robert , Mehrotra Sanjay 
Published: October 2008

Linear programs that arise in two-stage stochastic programming offer a particularly difficult test of the robustness of interior-point methods. These LPs are typically very large, yet incorporate “dense columns”—corresponding to the first-stage variables—that rule out the standard approach of solving the so-called normal equations. We compare two alternative approaches by running tests on six groups of stochastic linear programs that have been used in previous studies. We find that the augmented system approach consistently requires an amount of work that is very nearly linear in the number of scenarios, whereas the column-splitting approach requires a less predictable amount of work that grows worse than quadratically in some cases. We conclude by explaining how the differences between the two approaches can be viewed as a consequence of the way in which myopic elimination strategies deal with the block-structured matrices involved. Our analysis also leads to a useful comparison of the augmented system approach with the Schur complement approach considered in other recent research. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
Management Communication Analysis
Authors: Bennett J. G. 
Published: October 2008

Until recently, it has been assumed that within a corporation communications follow the lines drawn upon an organization chart. With this goes the belief that with clarity, a judicious balance of authority and cajolery, and the need to keep the organization going, the flow of messages will do what is required. Since failure of communication is, throughout the world, recognized as the principal cause of disputes and error of management, these assumptions must become suspect. Communication analysis is more than a branch of management science; it is the basic instrument of the science as mathematics is the basic instrument of engineering. As mathematicians use instruments like computers to expedite their work, communications analysts use media; but, in neither case does the instrument do the creative work. In communication systems, the basic problems arise from human relationships, and for this reason it is a mistake to suppose that communication consists in the flow of orders and information and that the obstacles to communication are mainly economic and political. The real purpose of any communication is to evoke a positive response, whether in the form of overt action or a change of inner attitude. A message that has no effect upon either the behavior or the attitude of the recipient is not a communication.
Note from Chairman of Student Chapters
Authors: Halbrecht Herbert Z. 
Published: October 2008

We are anxious to organize Student Chapters of TIMS on every campus where we can attract enough students and faculty advisors to make such chapter activities viable, useful, and interesting. Possibly even joint chapters could be formed by two or three schools in the same area. We are in the process of organizing panels of chief executives and senior operating officers of a number of the country's leading industrial, commercial, and financial corporations, nonprofit research firms, and major governmental agencies to lead seminars discussing how they actually use management sciences, what they really do, and what they foresee in terms of future functions as prospects for the students should they decide to enter industry.
Observations on Computer Simulation in the Civilian Concerns of Government
Authors: Tribus Myron 
Published: October 2008

Simulation is a tool made practical by the capabilities of the modern highspeed computer, a tool which may be used by enlightened decision makers in the public and private sectors to gain insights into very complex situations. The advent of meaningful simulation models to help understand and contemplate large complex systems is relatively new. At present there is no universal agreement on the meaning of the term. In my own view, simulation implies a concern with dynamics—that is, the use of any mathematical or physical model which may be moved through time. Simulation may or may not involve the use of Monte Carlo techniques, but the prime thought here is that models are time dependent and may be used to study the effects of decisions made in one time period on behavior in subsequent time periods.
What is a Management Scientist?
Authors: Simon Leonard S. 
Published: October 2008

Early in November, approximately 2,000 questionnaires were mailed to a randomly selected sample of the membership of The Institute of Management Sciences. The stated goal of the questionnaire was to accumulate data from which a discussion could commence about the definition of a management scientist. Each of the questions was of an attitudinal nature and dealt with the individual's perception of himself and/or his professional colleagues who considered themselves management scientists. A copy of the questionnaire is provided in Exhibit I. The statements focused on three areas, namely the person's viewpoints on the training necessary to be a management scientist, the job characteristics of a management scientist, and the contribution of the management scientist to his organization. There were several statements related to each area, but these were randomized in actual presentation of the questionnaire.
Management Science Roundup
Authors: Bucatinsky Julio 
Published: October 2008

—“Quantitative Techniques in Accounting”; —“Corporate Planning”; —“Simulation Applications”; —“More on Simulation”; —“Model of a Profit Sharing Plan”; —“Management Science in Banking”; —“Marketing and Financial Planning”; —“To Learn How Higher Education Ticks”; —“1970 Management Systems Conference”; —“Seen Elsewhere: (1) Modeling of Distant Futures, (2) Algorithms, (3) Approximation by Linear Programming, and (4) Decision Theory Analysis”; —“Bulletin Board”.
Management Science Roundup
Authors: Bucatinsky Julio 
Published: October 2008

Updates about introducing new features to the column. In this issue: —“Specials: (1) Unemployment—Halbrecht, (2) Corporate models—Gershefski and Allan”; —“Correspondents: (1) Denver—Auglund, (2) Monterrey—Herrera, (3) New York—Koo”; —“Seen Elsewhere: (1) Management science and top management, (2) Least squares, (3) Large LP models, (4) Layout planning, (5) Analysis of covariance, (6) Management education, (7) Organization, (8) Multi-facility production-transportation, (9) Industrial Engineering, (10) Need for achievement”; —“Bulletin Board: (1) Meetings and symposia, (2) Summer courses, (3) Personal notes, (4) Notices”; —“Deadlines for future issues of INTERFACES”.
Reflections on the Role and Function of Managerially-Oriented Professional Societies
Authors: Weinwurm George F. 
Published: October 2008

Most of the managerially-oriented professional associations with which TIMS members are likely to be involved do a creditable job of that which has traditionally dominated their attention—helping professionals communicate with each other. By means of journals, meetings, proceedings, tutorial seminars, and the like, these organizations make it possible for any person who, by any reasonable standard, has something to say that is relevant to these societies' interests to have his say in print or on the rostrum. Surely these activities make a substantial contribution to the development of the knowledge which the managerially-oriented professions embody and to the sense of community which their associations represent. Yet, this obsession with communication for the sake of communication seems to many to have reached the point where it has become counter-productive. For instance, most professional associations believe themselves to be irretrievably committed to having at least one, and often two or more, major meetings a year—to maintain the members' interest, so the reasoning goes. The number of parallel sessions in a meeting often seems to be more a function of the physical arrangement of the most expansive facility the organization's credit can afford rather than devolving from any particular purpose that attaches to an individual meeting. The number of speakers in many a session seems to be determined more by the number of papers that have been contributed rather than by any obligation to the speakers whose papers have been accepted. In all, these professional bazaars are the natural result of the widely-accepted notion that every member and interest group ought to have an equal right to be heard—every time.
Blood Contamination: An Industry Hours Model
Authors: Hemmer Hugh D. 
Published: October 2008

Considerable good research has been done on the subject of lead in blood. Most of it has been concerned with the effects of automobile exhaust fumes upon ordinary folk going about their everyday business. Less has been devoted to people working in lead contaminated industrial environments. Much of what has been done in this area has been in the nature of statistical surveys, relating average levels of blood lead to particular job situations and surrounding these averages with measures of dispersion and confidence. Nearly all these industrial surveys conclude that personal work-cleanliness is the major reason for dispersions around the averages. After a study in one of our factories, our Operational Research group was forced to the same conclusion, but with a slightly different twist. As always, the problem was stated with urgency. A few blood lead figures had gone higher than expectations: why? A quick study of the usual statistical type showed conclusively that all the norms were being held; the factory was not generally out of control. Those people with high blood lead concentrations were moved and everyone quieted down again. But OR continued.