bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Nonlinear Optimization Model of Water Allocation for Hydroelectric Energy Production and Irrigation
Authors: Rabinowitz Gad , Mehrez Abraham , Oron Gideon 
Published: November 2008

An optimal decision and control model was developed and used for dual purpose allocation of water from a reservoir. The model was constructed for the Hazbani-Dan Water System in the Upper Galilee (Israel). In this system about half of the Dan River water enters and is stored in a reservoir and is then released via a 70″ pipe either to a hydroelectric power station or to agricultural fields for irrigation. The electricity generated is sold to the national electricity utility according to a three-tiered pricing system which is a function of the time in the day and the season. The decision and control model maximizes the expected return on energy production subject to storage capacity and flow limitations. According to the policy of the system management, water demand for irrigation has to be satisfied and so it is taken as a constraint in the model. The following paper develops the model, exploring the feasibility conditions of the model and the uniqueness of the solution. An example containing a sensitivity analysis is given.
Strategies for the Probabilistic Lot-Sizing Problem with Service-Level Constraints
Authors: Bookbinder James H. , Tan Jin-Yan 
Published: November 2008

We formulate a stochastic-demand version of the single-stage lot-sizing problem with time-varying demand, incorporating a service-level constraint on the probability of a stockout. Three strategies are studied. The “static uncertainty” strategy, in which lot-sizing decisions for every period must be made at the beginning of period 1, is shown to yield an equivalent deterministic problem with time-varying demands for which optimal or good heuristic solutions exist. The procedure by which this equivalent problem is obtained is computationally simple. The “dynamic uncertainty” strategy allows subsequent lot sizes to be chosen on the basis of demands that have become known at a later point in time. The “static-dynamic” uncertainty approach combines features of the above two strategies and yields an equivalent linear program for any given order schedule. Relationships are suggested between these strategies and various aspects of rolling horizon production planning. Arguments are given that in such an environment, the static uncertainty strategy is the most straightforward to modify and “roll along” as new demands become known. Good results are found when this procedure is applied to some 300-period stochastic-demand problems using rolling horizons of between 2 and 12 periods in length.
Prospect Versus Utility
Authors: Currim Imran S. , Sarin Rakesh K. 
Published: November 2008

We show how to calibrate a prospect model of decision making under risk for an individual. The prospect model is empirically compared to a utility model on two criteria, verification of the postulates of each model, and predictive accuracy. The empirical comparison is performed via three experiments. In Experiment 1, predictive accuracy of the models is compared in nonparadoxical situations, those which favor neither model. In contrast the predictions in Experiment 2 are for paradoxical choices, those which favor the prospect model. In Experiment 1, the prospect model is compared to a model comprising a utility function which permits separate risk attitudes for gain and losses, and hence is more flexible than a utility model as traditionally assessed. In contrast the utility model in Experiment 3 is assessed as is traditionally done assuming constant risk attitude across gains and losses. Several calibration procedures are contrasted across experiments. Our results show a high degree of consistency with the postulates of both models. On predictive accuracy the prospect model outperforms the utility model for paradoxical choices. However, for nonparadoxical situations there is little difference in the predictive ability of both models.
Technological Accumulation, Diversification and Organisation in UK Companies, 1945–1983
Authors: Pavitt K. , Robson M. , Townsend J. 
Published: November 2008

A survey of more than 4,000 significant innovations and innovating firms in the UK from 1945–1983 shows that the scope and organisation of technological activities vary greatly as functions of firms' principal activities and size. 1. Technological opportunities and threats are greatest in firms in chemicals and engineering. Opportunities in such science-based and specialist supplier firms in general emerge horizontally (in related product markets) and downstream (in user sectors). In scale-intensive (e.g. steel, vehicles) and supplier-dominated (e.g. printing, construction) firms, opportunities tend to be upstream in related production technologies. Breakthrough innovations in science-based firms also induce clusters of technological opportunities upstream for suppliers, horizontally for partners, and downstream for users. Their effective exploitation requires diversity of firms' technological activities greater than that strictly required for current output. 2. The nature of technological opportunities, and of organisation for their exploitation, also varies with firm size. Firms with fewer than 1,000 employees have major opportunities with specialised strategies in mechanical engineering and instruments. The prevalence of broad front technological strategies, and of divisionalisation, increases sharply with firm size, together with dependence on formal R and D activities. The size of innovating divisions has diminished sharply over the period. Divisionalisation improves the “goodness of fit” between the core business of innovating divisions and the innovations themselves, but 40% have remained consistently outside the core business of divisions. 3. These findings help identify the key tasks of technological strategy in firms in different industries, and of different sizes. Thus, in large firms, divisionalisation can create the small size of unit conducive to effective implementation, but it cannot absolve central management from the continuous task of matching technological opportunities with organisational forms and boundaries.
A Discrepancy Model of End-User Computing Involvement
Authors: Doll William J. , Torkzadeh Gholamreza 
Published: November 2008

Within the context of traditional data processing, the MIS literature has devoted considerable attention to the relationship between user involvement and MIS success: unfortunately, this research has produced conflicting results. After reviewing these results, Ives and Olson provide a framework for research on user involvement. Although their framework uses cognitive and motivational psychological mechanisms to explain the linkage between user involvement and MIS success, the contingency variables they identify do not pertain to individual differences between users. Thus, the framework has limitations that reduce its usefulness for explaining conflicting research findings, and its applicability to the end-user computing environment. End-user computing is an emerging phenomenon characterized by substantial differences between individuals in skill and motivation. The unique aspects of this dynamic end-user environment are identified here and an end-user involvement construct is described. Next, after reviewing the participative decision making literature, a model of end-user involvement based upon Alutto and Belasco's discrepancy concept of participation is presented. Focusing on individual differences, this model hypothesizes a contingency relationship between perceived involvement, desired involvement, and end-user satisfaction. Three intervening psychological mechanisms described by Locke and Schweiger (value attainment as well as cognitive and motivational) are used to provide a theoretical rationale for the linkage between involvement and end-user satisfaction. The model is empirically examined using a sample of 618 respondents from 44 firms. The results tend to support the contingency hypotheses. The usefulness of this model for reconciling conflicting research findings in the user involvement literature is discussed, and suggestions for further research are described.
Flight Scheduling and Maintenance Base Planning
Authors: Feo Thomas A. , Bard Jonathan F. 
Published: November 2008

In an effort to control costs, airlines have begun to concentrate on their maintenance operations as a potential source for savings. Nevertheless, federal regulations and internal safety policies effectively limit cost savings to improvements in productivity and scheduling. The purpose of this paper is to present a model that can be used by planners to both locate maintenance stations and to develop flight schedules that better meet the cyclical demand for maintenance. The problem is formulated as a min-cost, multicommodity flow network with integral constraints, and solved using a two-phase heuristic. The procedure is demonstrated with data supplied by American Airlines for their Boeing 727 fleet. The results show a significant improvement over current techniques, and indicate that substantial cost reductions can be achieved by eliminating up to 5 of the 22 maintenance bases now in operation. Similar results were obtained for American's Super 80 and DC-10 fleets. Perturbation analysis confirms the robustness of these findings, and suggests that loss in flexibility due to interruptions in the flight schedule will be negligible.
Planning for Surprise: Water Resources Development Under Demand and Supply Uncertainty I. The General Model
Authors: Erlenkotter Donald , Sethi Suresh , Okada Norio 
Published: November 2008

A study of water resources development in South Sweden revealed that water consumption unexpectedly stopped growing after construction had begun on a large project to expand water supplies. The project had a long lead time for completion, and planning had been based on traditional deterministic forecasts of future water use. To explore the implications of such an uncertain structural shift in future consumption patterns, we develop a model for determining the timing for initiating such a project. In this model, the original consumption forecast may be disrupted at some random future time by an event called a “surprise.” As in the Swedish situation, we have modeled the surprise as an unexpected stagnation in future demand growth and benefit levels. We show that this form of uncertainty makes desirable delaying the initiation of the project beyond the time optimal under the original forecast. We then extend the model to include the lead time for the project as a variable, and demonstrate that the lead time should be reduced from that optimal under a deterministic future. Finally, we incorporate the option of abandoning the project when the surprise occurs, and show that higher salvage values for the project lead to earlier optimal commitment times.
Industry Concentration and Allocation of Resources to Basic Research
Authors: Joglekar Prafulla , Hamburg Morris 
Published: November 2008

While the mainstream of Western economic thought believes in competitive markets, the Schumpeterian school considers concentrated industry to be the ideal vehicle for the advancement of industrial technology. Empirical evidence on the Schumpeterian hypothesis that a concentrated industry allocates relatively more resources to its research and development (R&D) activities has been inconclusive. We believe the reason is that the Schumpeterian hypothesis is too general and vague. The fact is that there are several dimensions of industrial concentration, for example, total number of firms in an industry, interfirm differences on a variety of characteristics such as sales, assets, resources, and so forth. Similarly, R&D activities are of several types such as long-term or short-term research, and basic research or applied research and development. Unfortunately, modeling efforts focusing on resource allocation by specific types of concentrated industries to specific types of R&D activities are almost nonexistent, with the exception of Joglekar and Hamburg (Joglekar, P., M. Hamburg. 1986. A homogeneous industry model of resource allocation to basic research and its policy implications. Management Sci. (February) 225–236; Joglekar, P., M. Hamburg. 1987. Industry resource allocation to basic research under normally distributed benefits. Decision Sci. (Winter) 1–24.) who showed that industries consisting of smaller numbers of firms allocate relatively greater amounts of resources to their basic research than industries consisting of larger numbers of firms. Extending Joglekar and Hamburg's models here we find that when two industries consist of the same number of firms, in most cases, a heterogeneous industry falls as short of its Pareto optimal investment in basic research as its comparable homogeneous counterpart. Numerical examples suggest that in some cases, concentrated (heterogeneous) industries may do worse. Policy implications of the results as well as directions for further research are discussed.
Control Policies for the MX/G/1 Queueing System
Authors: Lee Hyo-Seong , Srinivasan Mandyam M. 
Published: November 2008

The MX/G/1 queueing system is studied under the following two situations: (1) At the end of a busy period, the server is turned off and inspects the length of the queue every time an arrival occurs. When the queue length reaches, or exceeds, a pre-specified value m for the first time, the server is turned on and serves the system until it is empty. (2) At the end of a busy period, the server takes a sequence of vacations, each for a random amount of time. At the end of each vacation, he inspects the length of the queue. If the queue length is greater than, or equal to, a pre-specified value m at this time, he begins to serve the system until it is empty. For both cases, the mean waiting time of an arbitrary customer for a given value of m is derived, and the procedure to find the stationary optimal policy under a linear cost structure is presented.
Efficient Corporate Diversification: Methods and Implications
Authors: Amit Raphael , Livnat Joshua 
Published: November 2008

This study develops and tests a measure of efficient corporate diversification (ECD) that compares the variability of a firm’s revenues with the variability of a minimum-variance portfolio of businesses that maintain the same sales growth rate. According to ECD, which incorporates the exposure of a firm to business cycle fluctuations, a firm is considered more efficient the higher its ratio of minimum variance to the realized variance. The empirical results indicate that efficient diversifiers manage to reduce the variability of their returns without sacrificing profitability. Moreover, such firms have a more favorable trade-off between risk and return in the equity market. Further, efficient diversifiers are found to be less diversified as measured by the extent of operations in different SIC industries. Instead, they operate in related business segments that have differential responses to business cycle changes and thereby enjoy the benefits from related diversification while minimizing their operating risk.
Generalized Assignment with Nonlinear Capacity Interaction
Authors: Mazzola Joseph B. 
Published: November 2008

The utility of the generalized assignment problem (GAP) is well known in regard to resource allocation problems arising in the areas of production planning, scheduling, and facility location. This paper introduces an important generalization of the GAP, which is called the 0-1 generalized assignment problem with nonlinear capacity constraints (NLGAP) and which allows for capacity interaction among tasks assigned to the same agent. For example, NLGAP can be used to model the hierarchical production planning problem involving the assignment of product families to production facilities in the case where process changeover gives rise to nonlinear capacity interaction among product families assigned to be produced at the same facility. Other applications of NLGAP occur readily throughout the areas of production planning and scheduling. We define a branch-and-bound algorithm for the NLGAP. This algorithm draws upon the underlying structure of the problem by combining in a novel manner recent advances in both nonlinear 0-1 programming and bounding techniques for the GAP. A heuristic for obtaining approximate solutions to NLGAP is also defined. We discuss computational experience with both the exact algorithm and the heuristic. The computational results demonstrate that the heuristic is extremely effective in obtaining near-optimal solutions and that the branch-and-bound algorithm can solve to optimality NLGAPs with 5 agents, 20 tasks, and over 1000 nonlinear terms per constraint.
Perceptual Position and Competitive Brand Strategy in a Two-Dimensional, Two-Brand Market
Authors: Carpenter Gregory S. 
Published: November 2008

Brand positioning and competitive reaction are important determinants of optimal brand strategy. Analyses of brand strategy have focused on optimal pricing and positioning issues using either empirical models of perceptions and preferences, game theory to examine competition, or both. However, the important issues of advertising and distribution strategy have not been fully addressed. This paper analyzes competition and strategy between two brands that compete in a two-dimensional market with advertising and distribution spending, in addition to prices and product positions. In particular, for a unimodal taste distribution of ideal points we show how • optimal competitive (Nash equilibrium) marketing mix levels and profits depend on the positions of both brands, • brands can reposition to increase profit and under what conditions these strategies imply minimum versus maximum differentiation positioning equilibria, and • how the intensity of advertising and distribution competition affect equilibrium brand positions.
Dependability and Organizational Bankruptcy: An Application of Agency and Prospect Theory
Authors: D'Aveni Richard A. 
Published: November 2008

This paper proposes and tests a new model of organizational bankruptcy based on agency and prospect theory. The paper argues that debtors with unprestigious top managers, low liquidity and high leverage signal that they will be undependable exchange partners. The model proposes that survival is contingent on maintaining an acceptable, minimum level of these financial and managerial assets. If a firm falls below that threshold level, it has a higher probability of bankruptcy because creditors withdraw their financial support from the debtor. Consistent with agency theory, this implies that bankruptcy can be viewed as the legal resolution of severe shareholder-creditor conflicts about the levels of financial and managerial assets that the debtor should maintain. This new model proposes that maintaining a minimum level of these assets is a necessary, but not sufficient, condition for bankruptcy. Some undependable firms delay bankruptcy by using strategies that create the hope that they will become dependable in the future. According to prospect theory, these strategies work because creditors wish to avoid recognizing significant losses, and thus take on more risk than they might otherwise assume.
Firm-Level Productivity and Management Influence: A Comparison of U.S. and Japanese Automobile Producers
Authors: Lieberman Marvin B. , Lau Lawrence J. , Williams Mark D. 
Published: November 2008

This study compares the productivity of six major US and Japanese motor vehicle manufacturers—General Motors, Ford, Chrysler, Toyota, Nissan and Mazda—from the early 1950's through 1987. Techniques of productivity measurement, conventionally applied at the level of industries or national economies, are adapted for the analysis of individual firms. Several potential determinants of growth in productivity are evaluated, including economies of scale, adoption of “just-in-time” manufacturing, and changes in top management. The results show that productivity improvement by the six motor vehicle producers was attained primarily through more efficient utilization of labor; long-term growth in capital productivity was negligible for most firms. The three Japanese producers had achieved higher labor productivity than their US counterparts by the late 1970's. More recently, though, differences among firms within each country have become large relative to the gap between the US and Japan. Early productivity growth for Japanese producers was derived in part from the achievement of scale economies, but this source of improvement was largely exhausted by the mid-1960's. In both countries, significant shifts in the growth rate and level of firm productivity have followed changes in top management.
The Cooperative Venture Formation Process: A Latent Variable Structural Modeling Approach
Authors: Fornell Claes , Lorange Peter , Roos Johan 
Published: November 2008

This article addresses management process issues for forming cooperative ventures with an increased likelihood of subsequent success. Based on Roos (1989) the cooperative venture formation process is conceptualized in terms of three theoretical constructs: the extent of sufficient “internal push” for the project, the breadth and depth of “analytical scope,” and the strength of key “stakeholder support.” These constructs are related to subsequent perceived performance. Data from sixty seven firms were collected and analyzed via latent variable structural modeling a partial least square (PLS). One key contribution of this article is the modeling approach to strategic formation process. It contributes to an existing, but not very well developed, theory regarding strategy formation processes. The PLS method used in this study is quite unique within strategy research. As such, it contributes to methodology development in the strategy research field. The main managerial implication is that the process by which a cooperative venture is formed should largely be seen as a step-by-step approach—not a discrete decision. If the three fundamentals discussed in the article are thoroughly addressed, we can up the ante for success during implementation and, therefore, subsequent performance.
Information Technology Implementation Research: A Technological Diffusion Approach
Authors: Cooper Randolph B. , Zmud Robert W. 
Published: November 2008

Based on the innovation and technological diffusion literatures, promising research questions concerning the implementation of a production and inventory control information system (material requirements planning: MRP) are identified and empirically examined. These questions focus on the interaction of managerial tasks with the information technology and the resulting effect on the adoption and infusion of that technology. Using a random sample of manufacturing firms across the United States, we find that this interaction does indeed affect the adoption of MRP, though it does not seem to affect MRP infusion. These results support the notion that though rational decision models may be useful in explaining information technology adoption, political and learning models may be more useful when examining infusion.