bluuebunny/crossref_metadata_2025 huggingface dataset:
The Practice of Management Science in R&D Project Management
Authors: Liberatore Matthew J. , Titus George J.
Published: November 2008

The results of an empirical study on the current usage of quantitative techniques for R&D project management in “Fortune 500” industrial firms are presented. A nonrandom sample of 40 respondents from 29 firms were selected to represent a mix of industrial sectors and geographic regions. The information was obtained via personal interview of R&D budget heads and some high level staff. Extensive demographic data on the respondent and his company were collected and related to familiarity and usage of project management techniques. Data were also collected on the perceived impact of techniques on project decision making, and any recent/planned changes in the cadre of techniques. Heavy use and high perceived impact of financial methods for project selection, selective use of network models, some dissatisfaction over the methods available for project scheduling and control, and no usage of mathematical programming models for R&D resource allocation were key findings. As a result, R&D managers must have a thorough understanding of the capital budgeting techniques used by their organizations. Also, the initial training for R&D managers in project management should provide a broad-based introduction to the available methods and techniques, while emphasizing organizational “fit” considerations. Finally, it is suggested that R&D managers enlist the support of management scientists in the development of decision support systems for R&D project management, especially for multi-project planning and control.
A Goal Seeking Investment Model
Authors: Cogger K. O. , Joy O. M. , Ruland W. , Yu P. L.
Published: November 2008

A probabilistic investment model is formulated as a Wiener process with a barrier. A planning horizon, targeted rate of return, discount rate, and the mean and variance rate of return are the important parameters in the model. Sensitivity analyses are studied. Several significant statements can be made: (1) contrary to traditional mean-variance portfolio models, rate of return variance may not always be an undesirable characteristic, since higher variance can increase the chances of achieving certain types of investment goals; (2) one can almost always achieve certain types of investment goals if the time horizon is sufficiently long.
The Customer Contact Model for Organization Design
Authors: Chase Richard B. , Tansik David A.
Published: November 2008

The literature on organization design has been dominated by descriptive models in its dealing with structure and operations. This paper takes an alternative view advocating the use of a normative model to be used in the design of service organizations. This model sees the extent of customer contact with the service organization as a major variable affecting system performance and advocates reconfiguring the structure of the service organization to reflect this impact. The discussion describes a taxonomy used to classify firms along the contact dimension and develops 13 propositions which convey critical distinctions between high and low contact services. Application of the model for managerial decision making involves the use of decoupling and the paper identifies factors which favor/disfavor decoupling in light of existing and desired service delivery objectives.
A Multi-Item Maintenance Center Inventory Model for Low-Demand Reparable Items
Authors: Schaefer Margaret K.
Published: November 2008

In many military and commercial contexts, complex equipment undergoes scheduled maintenance overhauls at regular intervals during which all failed components are replaced. Failure to have replacements on hand for all failed parts requires emergency measures at premium cost. When reparable parts are highly reliable and expensive, both holding and shortage costs are high. This model determines the reparable parts inventory for a maintenance center under three alternative criteria: (1) maximizing job-completion rate subject to constraint on total holding costs, (2) minimizing total holding costs plus expected job-noncompletion costs, and (3) minimizing total holding costs subject to a required minimum job-completion rate. Exact solutions may be obtained using dynamic programming. Approximate solutions, found easily by marginal analysis, have readily computed bounds on possible error. The solution methods for the three formulations are illustrated in a simple example.
An Inspection Policy Model for Production Facilities
Authors: Luss Hanan
Published: November 2008

Inspection policy models describe stochastically failing systems in which failures are detected by inspections only. We develop such an inspection model for a production facility. The model generalizes the recent work of Munford as well as the classical work of Barlow et al. Revenues are accrued for each time unit in which the facility is known to be in good operating condition. The costs considered include inspection, operating and repair costs. We present a dynamic programming algorithm that maximizes the expected profit between two successive repairs. This algorithm is then imbedded within an iterative procedure that maximizes the expected profit per time unit and the expected profit per time unit of good operating condition.
Averages of Forecasts: Some Empirical Results
Authors: Makridakis Spyros , Winkler Robert L.
Published: November 2008

An alternative to using a single forecasting method is to average the forecasts obtained from several methods. In this paper we investigate empirically the impact of the number and choice of forecasting methods on the accuracy of simple averages. It is concluded that the forecasting accuracy improves, and that the variability of accuracy among different combinations decreases, as the number of methods in the average increases. Thus, combining forecasts seems to be a reasonable practical alternative when, as is often the case, a “true” model of the data-generating process or a single “best” forecasting method cannot be or is not, for whatever reasons, identified.
Dynamic Programming and the Smoothing Problem
Authors: Bellman Richard
Published: November 2008

A problem in the study of production smoothing leads to the problem of minimizing a linear form [Formula: see text] subject to constraints of the type xi ≧ 0, [Formula: see text]. A computational solution of this problem is given, using the methods of dynamic programming.
On the Caterer Problem
Authors: Prager William
Published: November 2008

In the present paper, the Caterer Problem is shown to be equivalent to a Hitchcock Distribution Problem [Hitchcock, F. L. 1941. The distribution of a product from several sources to numerous locations. J. Math. Phys. 20 224–230.] with a very special cost matrix. For the case q = p − 1, a simple procedure taking advantage of this fact is developed and shown to yield Jacobs' solution. The possible extension of the procedure to the case p − q > 1 is illustrated by a numerical example.
Solving the Transportation Problem
Authors: Ford L. R. , Fulkerson D. R.
Published: November 2008

A simplified description of a new computing procedure for the Hitchcock-Koopmans transportation problem is given, together with a step by step solution of an illustrative example. The procedure is based on Kuhn's combinatorial algorithm for the assignment problem and a simple “labeling process” for solving maximal flow problems in networks. The proposed computation appears to be considerably more efficient than the specialized form of the simplex method which is in common use.
Optimal Design and Utilization of Communication Networks
Authors: Kalaba R. E. , Juncosa M. L.
Published: November 2008

It is shown that a number of fundamental optimal routing and design problems for communication networks consisting of facilities for transmission, switching, relaying, etc., may be treated in a straightforward, computationally feasible manner by linear programming methods. These methods provide a general system approach for resolving the complex interactions among system capacities, users' demands, and economic factors. Various aspects of implementation and generalizations are discussed.
Thoughts on Linear Programming and Automation
Authors: Dantzig George B.
Published: November 2008

We have all become increasingly aware of the postwar trend towards automation, which is an advanced form of mechanization. Mechanization's purpose is to relieve man of certain duties using human energy for power; automation's purpose is to relieve him of certain mental tasks and the related physical tasks necessary for their expression. Most of us sense that electronic computers, which are themselves examples of automation, will play an important role in the mechanization of control processes of the routine type.

We note again that linear programming makes it possible to mechanize part of the higher order controls. It appears likely that as this mechanization becomes more accepted, it will be linked more and more to tighter production control. In a word, automation may become super-automation.
On a Dynamic Programming Approach to the Caterer Problem—I
Authors: Bellman Richard
Published: November 2008

In this paper, it is shown that the “caterer” problem, a problem in mathematical economics and logistics which has been discussed by Jacobs, Gaddum, Hoffman and Sokolowsky, and Prager, can be reduced to the problem of determining the maximum of the linear form, subject to a series of “triangular” constraints in the form of inequalities, under an assumption concerning the non-accumulation of dirty laundry. This maximization problem is solved explicitly, using the functional equation technique of dynamic programming.
The Trim Problem
Authors: Eisemann Kurt
Published: November 2008

A problem of primary significance to a variety of industries is the suppression of trim losses in cutting rolls of paper, textiles, cellophane, metallic foil, or other material, for the execution of business orders. This problem is amenable to solution by the application of mathematical tools. We shall illustrate the general treatment of such problems by demonstrating a numerical example.
A Note on the Modigliani-Hohn Production Smoothing Model
Authors: Manne Alan S.
Published: November 2008

Modigliani and Hohn [Modigliani, F., F. E. Hohn. 1955. Production planning over time. Econometrica 23 (1, January) 46–66.] have formulated a production planning and inventory control model that appears relevant to an important class of non-stochastic decision-making problems. It is the purpose of this note to suggest: (1) that the Modigliani Hohn problem may be studied in terms of linear programming as well as through the calculus model originally employed; (2) that by working through the stock-flow relationships, it is possible to effect certain conceptual and computational improvements over Edward Bowman's original method for converting this type of problem into the “transportation” form [Bowman, E. H. 1956. Production scheduling by the transportation method of linear programming. J. Oper. Res. Soc. America 4 (1, February) 100–103.]; and (3) that the linear programming version is especially suitable for tracing out the cost implications of stabilizing the work force at alternative levels. Like the “caterer problem” [Jacobs, W. 1954. The caterer problem. Naval Res. Logist. Quart. 1 (2, June) 154–165.] and the “warehousing problem” [Charnes, A., W. W. Cooper. 1955. Generalizations of the warehousing model. Oper. Res. Quart. 6 (4, December) 131–172.], this linear programming model represents another instance in which every basis is pure triangular and contains no elements but zero, +1, and −1.
The Development of Organizations in a Laboratory
Authors: Guetzkow Harold , Bowes Anne E.
Published: November 2008

Does it seem feasible to attempt acceleration of the development of basic knowledge about organizations by utilizing the methodological advances which have occurred in the study of small groups? Specifically, how might the small group laboratory procedures of the social psychologist and sociologist be adapted to the study of organizations? Someday it may be possible to characterize social collectivities on a “meaningful set of orthogonal (independent) dimensions;” then “the definition of group and the discrimination of group from no-group [will] become arbitrary matters of convenience.” (1) In the meantime, it still seems fruitful to distinguish “small groups” from “organizations,” so that the extension of the methodologies from one area to the other is done with a modicum of circumspection. Groups are more or less stable configurations of persons in interaction. “Interaction” refers to the interlocking of the reactions of individuals to each other as stimulus objects.
Applications of Linear Programming in the Oil Industry
Authors: Garvin W. W. , Crandall H. W. , John J. B. , Spellman R. A.
Published: November 2008

This paper is the result of a survey made during the summer of 1956. It is a progress report on applications of linear programming by a number of oil companies. Examples are presented of applications to a variety of problems arising in the areas of Drilling and Production, Manufacturing, and Marketing and Distribution. The examples were selected to illustrate both the power and the limitations of present linear programming methods when applied to actual problems.
Sequential Production Planning Over Time at Minimum Cost
Authors: Johnson S. M.
Published: November 2008

Production of a given commodity is to be scheduled over time to meet known future requirements while minimizing total costs. The costs include both storage and production costs as functions of time. The unit production cost is an increasing function of the production rate. Previous solutions to this problem have involved complicated iterative procedures. A new approach brings out the basic principle involved and leads to a surprisingly simple solution. This coincides with a common-sense technique sometimes used in business.
The Dynamic Lot-Size Model with Stochastic Lead Times
Authors: Nevison Christopher , Burstein Michael
Published: November 2008

Optimal solutions for the dynamic lot-sizing problem with deterministic demands but stochastic lead times are “lumpy.” If lead time distributions are arbitrary except that they are independent of order size and do not allow orders to cross in time, then each order in an optimal solution will exactly satisfy a consecutive sequence of demands, a natural extension of the classic results by Wagner and Whitin. If, on the other hand, orders can cross in time, then optimal solutions are still “lumpy” in the sense that each order will satisfy a set, not necessarily consecutive, of the demands. An example shows how this characterization can be used to find a solution to a problem where interdependence of lead times is critical. This characterization of optimal solutions facilitates dynamic programming approaches to this problem.
Queues in Which Customers Receive Simultaneous Service from a Random Number of Servers: A System Point Approach
Authors: Brill Percy H. , Green Linda
Published: November 2008

We examine a multi-server queueing system with Poisson arrivals in which customers require simultaneous service from a random number of servers. Servers assigned to the same customer begin and end service concurrently. Service times are, in general, assumed to be exponentially distributed. A system point approach is presented as a framework for obtaining the waiting time distribution for each customer type. Explicit solutions are derived for the two-server system.
A Longitudinal Study of the Corporate Life Cycle
Authors: Miller Danny , Friesen Peter H.
Published: November 2008

A review of recent literature on the corporate life cycle disclosed five common stages: birth, growth, maturity, revival, and decline. Theorists predicted that each stage would manifest integral complementarities among variables of environment (“situation”), strategy, structure and decision making methods; that organizational growth and increasing environmental complexity would cause each stage to exhibit certain significant differences from all other stages along these four classes of variables; and that organizations tend to move in a linear progression through the five stages, proceeding sequentially from birth to decline. These contentions were tested by this study. A sample of 161 periods of history from 36 firms were classified into the five life cycle stages using a few attributes deemed central to each. Analyses of variance were performed on 54 variables of strategy, structure, environment and decision making style. The results seemed to support the prevalence of complementarities among variables within each stage and the predicted inter-stage differences. They did not, however, show that organizations went through the stages in the same sequence.
Asymptotic Properties of Some Confidence Interval Estimators for Simulation Output
Authors: Goldsman David , Schruben Lee
Published: November 2008

The classical confidence interval estimator commonly used in simulation is compared with four new estimators based on standardization of a time series presented in a previous paper. These new interval estimators are shown to have asymptotic properties that strictly dominate the classical estimator when used with data from independent simulation replications or means of batched observations from a single simulation run. Two of the new estimators also can be used with a single unbatched replication of a simulation program, a situation where the classical estimator is not defined.
Effect of Risk Aversion on Single Sample Attribute Inspection Plans
Authors: Moskowitz Herbert , Plante Robert
Published: November 2008

The impact of a decision maker's risk aversion on the choice of an optimal sampling plan is empirically examined for various batch sizes and prior distributions of the process quality level. These plans are compared to those of the classical linear cost model. The comparisons show that substantial differences in the characteristics of an optimal sampling plan (i.e., probability of acceptance, optimal sample size and expected total cost) occur when risk aversion is considered. A discussion of the optimization characteristics involved in the selection of a sampling plan is also presented. An optimization algorithm which obtains an optimal sampling plan based on the criterion of maximizing expected utility is proposed and evaluated.
A Perturbation Scheme to Improve Hillier’s Solution to the Facilities Layout Problem
Authors: Picone Christopher J. , Wilhelm Wilbert E.
Published: November 2008

This paper describes a new heuristic, the Revised Hillier procedure, for solving the facilities layout problem. It incorporates the effective features of the well-known Hillier procedure in combination with 3-way and 4-way exchanges to extend the neighborhood over which the search for a solution is conducted. Performance of the new heuristic is compared with that of CRAFT and the original Hillier procedure using a set of “standard” test problems; the Revised Hillier procedure yields solutions of higher quality while requiring only modest increases in computer run time.
Periodic Review Inventory Systems with Continuous Demand and Discrete Order Sizes
Authors: Tsitsiklis John N.
Published: November 2008

We study a single product inventory system with nonnegative setup cost in which the demand is a continuous random variable but orders are restricted to be integer valued. Optimal policies, when there are no setup costs, have a nice form. However, we show that, when the setup costs are nonzero, optimal policies may have a very counterintuitive form without any particular structure. We obtain a bound for the increase in costs resulting from the restriction of orders to be integers and define a suboptimal policy whose performance is within that bound.
Strong Formulations for Multi-Item Capacitated Lot Sizing
Authors: Barany Imre , Van Roy Tony J. , Wolsey Laurence A.
Published: November 2008

Multi-item capacitated lot-sizing problems are reformulated using a class of valid inequalities, which are facets for the single-item uncapacitated problem. Computational results using this reformulation are reported, and problems with up to 20 items and 13 periods have been solved to optimality using a commercial mixed integer code. We also show how the valid inequalities can easily be generated as part of a cutting plane algorithm, and suggest a further class of inequalities that is useful for single-item capacitated problems.
State of the Art—Utility Assessment Methods
Authors: Farquhar Peter H.
Published: November 2008

This paper is a comprehensive study of methods for assessing unidimensional expected utility functions. The paper describes the utility assessment process in decision analysis and then reviews problem formulation, sources of bias in preference judgments, and the analysis of risk attitudes. Two dozen utility assessment methods of which half appear for the first time are critically examined. These methods are grouped into preference comparison methods, probability equivalence methods, value equivalence methods, certainty equivalence methods, hybrid methods, paired-gamble methods, and other approaches. The paper emphasizes the nature of judgmental biases in comparing different assessment procedures. Since most multiattribute utility functions are decomposed into single-attribute functions, this study should facilitate such applications. The paper concludes with several directions for further developmental, empirical, and applied research.
Multiattribute Nonlinear Utility Theory
Authors: Fishburn Peter C.
Published: November 2008

Independence axioms similar to those proposed for multiattribute von Neumann–Morgenstern linear utility theory are examined in the context of new nonlinear utility theories developed by Chew and MacCrimmon, and Fishburn. These new theories weaken the independence axiom of von Neumann and Morgenstern, and Fishburn's theory does not require preferences to be transitive. The paper shows that axioms for independence between attributes lead to decompositions of utility for the nonlinear theories that are related to standard decompositions for linear utility.
Relational Systems of Preference with One or More Pseudo-Criteria: Some New Concepts and Results
Authors: Roy B. , Vincke Ph.
Published: November 2008

This paper proposes new concepts and new results which could lead to a more realistic preference modeling than in classical decision theory.

Sections 1–3 present four fundamental situations of preferences, their combinations and the concept of relational system of preferences. In §4, a particular case of relational system of preference is studied. It is associated with the concept of pseudo-criterion derived from the classical concept of criterion by adjunction of two thresholds. Some results are given, generalizing the properties of such well-known structures as complete preorders and semiorders.

Sections 5 and 6 emphasize the possibilities given by the preceding concepts to take the imprecisions, irresolutions and incomparabilities appearing in every concrete problem where several criteria must be considered into account.
On Efficient Solutions to Multiple Objective Mathematical Programs
Authors: Lowe T. J. , Thisse J.-F. , Ward J. E. , Wendell R. E.
Published: November 2008

This note develops properties of quasi-efficient solutions and explores interrelationships to the classical concept of efficiency. In particular, a point is a quasi-efficient solution to a multiple objective mathematical program if and only if it is an optimal solution to a scalar maximum problem for some set of nonnegative weights on the objectives. This result is then used to characterize the set of quasi-efficient solutions as the union of efficient solutions to a multiple objective problem over all nonempty subsets of the objectives.
Multiattribute Risky Choice Behavior: The Editing of Complex Prospects
Authors: Payne John W. , Laughhunn Dan J. , Crum Roy
Published: November 2008

This investigation draws upon concepts from prospect theory (Kahneman and Tversky [Kahneman, D., A. Tversky. 1979. Prospect theory: an analysis of decisions under risk. Econometrica 47 263–291.]) and multiattribute utility theory (Keeney and Raiffa [Keeney, R. L., H. Raiffa. 1976. Decisions with Multiple Objectives: Preferences and Value Tradeoffs. Wiley, New York.]) in an examination of the multiattribute risky choice behavior of 128 managers. The questions of how managers edit multiattribute prospects and how editing relates to various independence assumptions were explored. The major result is that managers appear to violate attribute independence in its general form, and especially in the form of the marginality assumption. The most common form of behavior observed was multiattribute risk aversion for prospects involving only gains and multiattribute risk seeking for prospects involving only losses. This result reinforces the importance of a target, reference point, or aspiration level that has been found in earlier studies of single attribute risky choice. Furthermore, the result casts doubt on such commonly used multiattribute utility functions as the additive, multiplicative, and multilinear forms. The implications of the results for the development of multiattribute risky decision aids are discussed.
Topological and Computational Aspects of Preemptive Multicriteria Military Personnel Assignment Problems
Authors: Klingman Darwin , Phillips Nancy V.
Published: November 2008

This paper first presents a brief reveiw of the multicriteria problems faced by the United States Army, Navy, and Marine Corps in making enlisted personnel assignment decisions. Then for the most complex of these military assignment problems, the Marine Corps problem, a new modeling and solution approach is presented with computational results for a problem having eleven criteria and approximately 10,000 constraints and 780,000 variables.

Other contributions of this paper include: New insights into the effects on model structure and solution efficiency of handling preemptive multiple criteria sequentially versus simultaneously. Derivation of an excellent convex proportional fill function. Providing multicriteria researchers with a class of large-scale test problems.
Introduction Strategy for New Products with Positive and Negative Word-of-Mouth
Authors: Mahajan Vijay , Muller Eitan , Kerin Roger A.
Published: November 2008

Existing innovation diffusion models assume that individual experience with the product is always communicated positively through word-of-mouth. For certain innovations, however, this assumption is tenuous since communicators of the product experience may transfer favorable, unfavorable, or indifferent messages through word-of-mouth. This paper examines a diffusion model for products in which negative information plays a dominant role, discusses its implications for optimal advertising timing policy and presents an application to forecast attendance for the movie Gandhi in the Dallas area.
Maximization of Labor Productivity Through Optimal Rest-Break Schedules
Authors: Bechtold Stephen E. , Janaro Ralph E. , Sumners De Witt L.
Published: November 2008

This paper focuses upon the maximization of labor productivity through selection of the optimal number, duration, and placement of rest breaks. It is demonstrated that resolution of the limited validity associated with previous models leads to a mixed-integer quadratic programming formulation of this problem. Efficient analytic procedures are developed which allow solutions to be obtained in minutes using a hand-held calculator. Then, the characteristics, properties, and potential effectiveness of optimal solutions are examined through an illustration from an existing work environment. Issues relevant to the implementation of the models are presented in a summary of an initial experiment in which one of the models in this paper was used to select rest break policy. The results of this experiment indicated that the output achieved using the model's policy was 13% higher than the output achieved when the subjects used their own rest break policies. Several future research topics are also identified.
An Approach for Developing an Optimal Discount Pricing Policy
Authors: Lal Rajiv , Staelin Richard
Published: November 2008

This paper addresses the problem of why and how a seller should develop a discount pricing structure even if such a pricing structure does not alter ultimate demand. The situation modeled is most appropriate where the seller's product does not represent a major component of the buyer's final product, where the demand for the product is derived, or where the price is only one of many factors considered in making a purchase decision. A model of buyer reaction to any given pricing scheme is developed to show that there exists a unified pricing policy which motivates the buyer to increase its ordering quantity per order, thereby reducing the joint (buyer and seller) ordering and holding costs. As a result, the seller is able to reduce its costs while leaving the buyer no worse off and often better off. The model is extended to handle variable ordering and shipping costs and situations where the seller faces numerous groups of buyers, each having different ordering policies. Finally a case study is presented explicitly showing how the proposed pricing policy can be applied to the situation of a large seller selling to a number of different buyer groups.
Different Measures of Win Rate for Optimal Proportional Betting
Authors: Griffin Peter A.
Published: November 2008

It is well known that all betting systems applied to independent, repeated, and identically distributed trials will result in the same expected gain per average unit wagered as that which applies to a single trial. This paper develops the asymptotic and paradoxical manner in which that constant win rate is maintained for optimal proportional betting according to the Kelly criterion. The appropriateness of using this traditional measure of win rate for proportional betting is contrasted with that of various alternatives.
An Urban Allocation Model Combining Time Series and Analytic Hierarchical Methods
Authors: Cook Thomas , Falchi Paul , Mariano Reynaldo
Published: November 2008

Presented is a new application in urban economic forecasting. This method actively utilizes external information for household population forecasts. The purpose is to develop a more satisfying procedure as part of the management decision taking system. In the Portland Standard Metropolitan Statistical Area (SMSA), both time series and cross-sectional data are exploited. A transfer function-noise model is developed relating national output to SMSA employment. Household population for the SMSA is forecast utilizing the same statistical technique via a job opportunities/migration hypothesis. Forecasts are allocated to planning divisions within the SMSA by univariate stochastic models. However, these forecasts are adjusted after consideration of several land use indicators. The forecast standard errors are utilized and a hierarchical weighting scheme of the land-use indicators is developed within an allocation framework. Qualitative and quantitative information is merged to provide a more complete analysis and efficient estimates of the allocation weights.
Log Bucking and Lumber Manufacturing Using Dynamic Programming
Authors: Faaland Bruce , Briggs David
Published: November 2008

The process of converting a tree into finished lumber involves several interrelated steps. The two of greatest potential for improvement are cutting the felled tree into shorter logs (called bucking the tree) and sawing the bucked logs into lumber. Unlike previous work in the area, this paper considers the two activities together as a single production system. The model allows for variations in tree shape and quality which could be recorded by modern electronic scanners. Among the principal techniques used in the paper are dynamic programming for both bucking and sawing, and a procedure for calculating the distance between two polyhedral sets in R2. Computational experience is reported on trees with representative defect patterns, taper, and sweep.
An Analysis of Network Location Problems with Distance Constraints
Authors: Moon I. Douglas , Chaudhry Sohail S.
Published: November 2008

This paper concerns a class of network location problems with minimum or maximum separation requirements between (uncapacitated) facilities or between demand points and the facilities, or both. Its purpose is three-fold. First, it is to recognize distance constraints as increasing real life restrictions through various motivating illustrations. Using a new classification scheme, the paper introduces a variety of distance-constrained problems defined in a unified manner. These include a number of new problems. Second, it is to survey existing solution techniques, available only for a few of such constrained problems. Finally, it is to shed some light on yet unstudied problems by exploring possible extensions of some of the known solution techniques or discussing varying degrees of difficulties involved. In particular, the paper presents integer programming formulations of several new problems along with the results of applying linear programming relaxation methods. Although the computational experience is somewhat disappointing for some of these problems, the results provide greater insight into the problems. With the stated purpose, it is hoped that this paper will stimulate future research in this important problem area.
Network Programming Models for Production Scheduling in Multi-Stage, Multi-Item Capacitated Systems
Authors: Zahorik Anthony , Thomas L. Joseph , Trigeiro William W.
Published: November 2008

This paper investigates a multi-item, multi-level production scheduling problem with linear costs and production and inventory constraints at one key facility. Two multi-item problems—one in which the constraint was on shipping capability and one in which there was a final stage bottleneck machine—motivated the paper. A multi-item facilities-in-series problem is formulated, in standard fashion, as a linear program. Then we show that in certain important cases the 3-period problem is a network problem. This 3-period result is used as the basis for a rolling heuristic for T-period problems. The conditions under which this heuristic fails to find optimal solutions are discussed and computational comparisons to standard linear programming are given. Finally, we discuss ways of dealing with two constrained facilities and with setup costs.
Coordinated Replenishments in a Multi-Item Inventory System with Compound Poisson Demands
Authors: Federgruen A. , Groenevelt H. , Tijms H. C.
Published: November 2008

In many practical applications or multi-item inventory systems significant economies of scale can be exploited when coordinating replenishment orders for groups of items. This paper considers a continuous review multi-item inventory system with compound Poisson demand processes; excess demands are backlogged and each replenishment requires a lead time. There is a major setup cost associated with any replenishment of the family of items, and a minor (item dependent) setup cost when including a particular item in this replenishment. Moreover there are holding and penalty costs. We present an algorithm which searches for a simple coordinated control rule minimizing the long-run average cost per unit time subject to a service level constraint per item on the fraction of demand satisfied directly from on-hand inventory. This algorithm is based on a heuristic decomposition procedure and a specialized policy-iteration method to solve the single-item subproblems generated by the decomposition procedure. The model applies to multi-location inventory systems with similar cost structures for coordinated deliveries.
A Study of Production Smoothing in a Job Shop Environment
Authors: Cruickshanks Allan B. , Drescher Robert D. , Graves Stephen C.
Published: November 2008

We consider the problem of smoothing production in a job shop in which all production is to customer order and the demand process is a stationary stochastic process. We present an approach to production smoothing based on the concept of a planning window. A planning window is the difference between the promised delivery time and the planned production time for a product. It represents the degree of flexibility available for planning the production of committed orders. We characterize the production smoothing benefits for a range of planning windows by means of an approximate analytic model and a simulation study. These analyses show that substantial smoothing benefits result from small changes in the length of the planning window. We discuss the implementation of the production smoothing approach and illustrate this implementation with an industrial case study that was the motivation for this work.
A Perspective on Health and Safety Risk Analysis
Authors: Starr Chauncey , Whipple Chris
Published: November 2008

Health and safety risks are compared with financial risks, and the differences pertinent for risk evaluation and management are described. Such differences arise from the equities of risk distribution, the multiple stakeholders in the decision process, the opportunities for risk diversification, the interpretation of social values relating to risk choices, and in the political objectives in the decision process. Health and safety regulators are faced with the problem of making decisions involving large scientific uncertainties, public perceptions at odds with professional perceptions, uncertain and conflicting public values expressed through the political process, and difficult judgments of equity when risk and benefit are borne by different groups. The effect of highly publicized risk controversies on such regulatory decisions is described.
Risks of Catastrophic Derailments Involving the Release of Hazardous Materials
Authors: Glickman Theodore S. , Rosenfield Donald B.
Published: November 2008

Models are formulated and computed to assess the risks of hazardous materials releases in train derailments in terms of: the probability of any number of fatalities in an accident, the probability of any total number of fatalities from all the accidents in a year, and the frequency of accidents which result in any given number of fatalities. These functions are evaluated using data bases and analytical methods which provide estimates of exposure levels (traffic volumes, track conditions and population densities), spill occurrence and spill size probabilities, and fatal spill impacts (the size of the lethal area in any given accident scenario). Despite the sparsity of historical data, this methodology enables us to express the potential for catastrophic occurrences in quantitative terms, to compare these numbers with estimates of other risks, and to examine the effects of selective variations in the model inputs.
Effects of Federal Support on Company-Financed R and D: The Case of Energy
Authors: Mansfield Edwin , Switzer Lorne
Published: November 2008

For decades, policy makers in both the public and private sectors have been concerned with the question: What is the impact of changes in federal R and D support on company-financed R and D expenditures? This is one of the first empirical studies at a micro level of this topic. The results, which pertain to energy R and D, indicate a complementarity between government-financed and company-financed R and D, on the average, although there is a considerable amount of interfirm variation in this regard. In about one-third of the projects studied, federally-financed R and D projects suggested some further R and D into which the firm invested its own funds. The results of a logit analysis suggest that whether or not a government-financed R and D project results in such a spinoff depends on the extent to which the performing firm contributes to the formulation of the project’s goals and strategies.
User Involvement and MIS Success: A Review of Research
Authors: Ives Blake , Olson Margrethe H.
Published: November 2008

User involvement in the design of computer-based information systems is enthusiastically endorsed in the prescriptive literature. However determining when and how much, or even if, user involvement is appropriate are questions that have received inadequate research attention. In this paper research that examines the link between user involvement and indicators of system success is reviewed. The authors find that much of the existing research is poorly grounded in theory and methodologically flawed; as a result, the benefits of user involvement have not been convincingly demonstrated. Until higher quality studies are completed intuition, experience, and unsubstantiated prescriptions will remain the practitioner's best guide to the determination of appropriate levels and types of user involvement; these will generally suggest that user involvement is appropriate for unstructured problems or when user acceptance is important.

In order to foster higher quality integrated research and to increase understanding of the user involvement-system success relationship, the authors present the following: a conceptual framework into which previous research has been mapped that can provide direction to future efforts; a review of existing measures of user involvement and system success; a set of variables that have been proposed as potentially impacting the relationship between user involvement and system success.
A Revision of the Power Approximation for Computing (s, S) Policies
Authors: Ehrhardt Richard , Mosier Charles
Published: November 2008

A revision of the Power Approximation for computing (s, S) inventory policies is presented. The revision incorporates modifications which (1) ensure homgeneity in the units chosen to measure demand and (2) ensure the proper limiting behavior of S − s when the variance of demand is extremely small. Computational experience shows that the revision has operating characteristics that are typically within a few percent of optimal, which is nearly as accurate as the original Power Approximation.
A Quantity Discount Pricing Model to Increase Vendor Profits
Authors: Monahan James P.
Published: November 2008

In this paper, we analyze how a supplier can structure the terms of an optimal quantity discount schedule. The vendor's challenge is to adjust his present pricing schedule to entice his major customer to increase his present order size by a factor of “K.” Optimal levels for “K” and the corresponding price discount are determined in order to maximize the supplier's incremental net profit and cash flow. Implementation issues are discussed and future research needs identified.
An Examination of “Push-Pull” Theory Applied to Process Innovation in Knowledge Work
Authors: Zmud Robert W.
Published: November 2008

Because many organizations have not been successful in introducing new task and managerial methods into the workplace, considerable attention has been directed toward developing a more complete understanding of organizational innovation. Three separate literatures (organizational science, engineering/R&D management, and MS/OR/MIS implementation) have, in fact, been concerned with innovation and technology diffusion; however, surprisingly little integration among the three has occurred. This paper reports on a study which examined a key tenet from each of these literatures in an effort to construct a robust model of innovative behavior. Specifically, the study utilized survey data in examining the validity of “push-pull” theory (i.e., that innovation is most likely to occur when a need and a means to resolve that need are simultaneously recognized) as well as the importance of top management attitude toward an innovation and of organizational receptivity toward change. The research context involved the diffusion of six modern software practices into 47 software development groups.

While the model's independent variables explained a rather large amount of the variance in the use of these modern software practices, “push-pull” theory was not validated. A number of explanations are offered for the apparent failure of “push-pull” theory. Top management attitude and organizational receptivity toward change, however, were generally found to influence organizational innovation. As hypothesized, significant differences emerged in the factors influencing administrative and technical innovations with organizational receptivity toward change important only for the technical innovations. This suggests that organizational processes facilitating innovation should vary depending on the nature of the innovation involved.
Priority Scheduling and Spares Stocking Policies for a Repair Shop: The Multiple Failure Case
Authors: Scudder Gary D.
Published: November 2008

Improved scheduling rules and spares stocking policies are examined for a repair shop supporting a multi-item repairable inventory system with a hierarchical product structure. The results from an earlier paper are extended to the case where more than one unit fails in each item to be repaired. A variety of scheduling rules and methods for initializing the vector of spare parts are evaluated using a simulation of a representative shop. The results indicate that procedures which perform well when only a single unit fails also perform well when multiple failures occur. More complex rules, which recognize assembly mating requirements, do not appear to provide any significant improvement.
A Distributed Parameter Cohort Personnel Planning Model That Uses Cross-Sectional Data
Authors: Gaimon Cheryl , Thompson Gerald L.
Published: November 2008

The two types of mathematical manpower planning models that appear in the literature involve either longitudinal or cross-sectional formulations. Despite the high degree of realism achieved, the use of longitudinal models is limited because the implementation requires the knowledge of a large amount of historical personnel data that is often unavailable. The value of cross-sectional models requiring a minimal amount of data is diminished due to (1) the difficulty in transferring cross-sectional results into cohort information, and (2) an assumption implicit in the structure of these models stating that the movement of an individual from one grade in the organization to another is independent of that person's organizational age.

In this paper, we present a cohort (longitudinal) personnel planning model solved using distributed parameter optimal control theory that requires only cross-sectional data. We derive the optimal hiring, promotion, separation and retirement policies of an organization as functions of time and a person's organizational age and grade. In response to changing goal levels of manpower, we observe changes in the optimal policies and their subsequent effect on the career paths of cohort groups over time.
Blood Inventory Management: An Overview of Theory and Practice
Authors: Prastacos Gregory P.
Published: November 2008

Blood Inventory Management has attracted significant interest from the Operations Research profession during the last 15 years. A number of methodological contributions have been made in the areas of inventory theory and combinatoric optimization that can be of use to other products or systems. These contributions include the development of exact and approximate ordering and issuing policies for an inventory system, the analysis of LIFO or multi-product systems, and various forms of distribution scheduling. In addition, many of these results have been implemented, either as decision rules for efficient blood management in a hospital, or as decision support systems for hierarchical planning in a Regional Blood Center.

In this paper we attempt a review of the recent Operations Research contributions to blood inventory management theory and practice. Whereas many problems have been solved, others remain open and new ones keep being created with advances in medical technology and practices. Our approach is not to present an exhaustive review of all the literature in the field, but rather to address several important issues from a unified perspective of theory and practice, and point out new areas for further research.