Showing papers in "Infor in 1995"
TL;DR: The hybrid method developed in this paper is well suited for Open Shop Scheduling problems (OSSP), and the results obtained appear to be quite satisfactory.
Abstract: We present in this paper a new evolutionary procedure for solving general optimization problems that combines efficiently the mechanisms of genetic algorithms and tabu search. In order to explore the solution space properly interaction phases are interspersed with periods of optimization in the algorithm. An adaptation of this search principle to the National Hockey League (NHL) problem is discussed. The hybrid method developed in this paper is well suited for Open Shop Scheduling problems (OSSP). The results obtained appear to be quite satisfactory.
132 citations
TL;DR: It is illustrated that cross-evaluation can give better results (in terms of robustly recovering unobserved ‘real’ efficiencies) than simple DEA effi...
Abstract: There is a need to distinguish among efficient DMUs in Data Envelopment Analysis (DEA). We introduce cross-evaluation in DEA as a logical extension of the reference set count, an idea which is alre...
126 citations
TL;DR: In this article, the authors discuss the commonly used quantitative risk assessment (QRA) techniques and provide a review of measures of risk acceptability, focusing on the fundamentals of quantifying risks near transportation corridors.
Abstract: We are faced with various types of risks in our everyday lives and continue to be exposed to new risk sources. Decision makers are continually faced with deciding whether a new risk source should be allowed in a particular community. Before making such decisions, it is desirable to know what the existing risks are, and what additional risks a new facility would bring. Then, if there are established guidelines for risk acceptability, planning decisions can be made so that some segments of the society are not exposed to unduly high risks, especially risks over which they may have very little control.Quantitative risk assessment (QRA) techniques are playing an increasing role in analyzing safety of industrial systems, such as transportation networks or fixed industrial facilities. The present paper discusses the commonly used QRA techniques and provides a review of measures of risk acceptability. Particular emphasis is given to the fundamentals of quantifying risks near transportation corridors, whic...
86 citations
TL;DR: This paper considers the problem of developing effective routes for transporting hazardous materials for the case where the routing ends after the occurrence of the first accident, with constraints on the accident probabilities, the expected a prioririsk, the transportation cost, and the equity of risk.
Abstract: This paper considers the problem of developing effective routes for transporting hazardous materials for the case where the routing ends after the occurrence of the first accident. A multiple route situation is permitted, the objective being to minimize the expected risk of the first accident, with constraints on the accident probabilities, the expected a prioririsk, the transportation cost, and the equity of risk. A column generation technique is used to generate heuristic solutions. A brief summary of our results from extensive computational testing, based on a “real-life” hazardous materials routing scenario, is presented. Also presented is an example problem that illustrates several features of the model.
51 citations
TL;DR: In this paper, a multiobjective model for locating solid waste transfer stations (SWTS) examines the tradeoffs between minimizing costs and public opposition, while expected public opposition is modeled as a decreasing function of distance from the facility.
Abstract: Solid waste transfer stations (SWTS) are facilities where municipal refuse is transferred from collection trucks to long-haul trucks for more economical shipping to distant landfills. In this paper, a multiobjective model for locating SWTS examines the tradeoffs between minimizing costs and public opposition. The cost objective combines the transshipment and the fixed-charge problems, while expected public opposition is modeled as a decreasing function of distance from the facility. We believe this is the first location model for any type of undesirable facility to use an opposition function derived empirically from opinion survey data (Rahman, et al., 1992). A case study of Phoenix, Arizona uses actual data on sites, zones, tonnages, costs, and local residential attitudes. The model is calibrated to historical budget data for accuracy and also to explore the model’s sensitivity to various parameters. Six sets of multiobjective analyses generate noninferior tradeoff curves under various assumption...
44 citations
TL;DR: In this paper, an approach to calculate return-on-investment at the component process level is proposed using an extension of Kolomogorov's Complexity Theory, which can be used to measure value added by component processes before and after a reengineering effort.
Abstract: Today, there is no objective, countable way to measure value added by component processes before and after a reengineering effort and, therefore, no way to provide executives with return-based assurances. Objective value allocation among the component processes of a compound process cannot be gotten through existing approaches (e.g., generally accepted accounting practices, activity-based costing, economic value added, cost of quality, quality function deployment) (Drucker, 1993; Eccles, 1991; Johnson, 1992). These approaches focus on cost or various subjective assessments of value and cannot be used in return based financial ratios because they do not use comparably objective units of measurement (e.g., money). Using an extension of Kolomogorov’s Complexity Theory, this paper offers a solution to this problem. Specifically, this article proposes an approach to calculating return-on-investment at the component process level.
41 citations
TL;DR: A mobile inspection system that automates the very labor-intensive and therefore time-heavy and expensive process of manually inspecting trucks on the underlying transportation network to enforce rules regarding hazardous material transportation.
Abstract: To enforce rules regarding hazardous material transportation, regulating agencies need to make choices on where to inspect trucks on the underlying transportation network. If each inspectio...
41 citations
TL;DR: The number of routes obtained when varying the parameter across its permissible range is small enough, however, that the MAU formulation can be thought of as one that generates “MAU noninferior routes” before interacting with the decision maker.
Abstract: We show that a multi-attribute utility (MAU) formulation of the single shipment, cost-exposure, hazardous materials optimal routing problem can conceivably be solved with traditional shortest path algorithms. We argue, however, that the parameter scaling the single attribute cost disutility function into the two attribute cost-exposure disutility function could not be estimated to more than an order of magnitude. In a numerical study using the Columbus, Ohio highway network, we see that such an estimate is not precise enough either to specify a unique optimal route or to screen out a substantial number of routes as suboptimal when the optimal route is to be other than the minimum cost or minimum risk of exposure route. The number of routes obtained when varying the parameter across its permissible range is small enough, however, that the MAU formulation can be thought of as one that generates “MAU noninferior routes” before interacting with the decision maker. We speculate on the impacts of extend...
22 citations
TL;DR: In this paper, the authors consider the two-dimensional guillotine cutting problem and compare their performance with some randomly generated examples, and propose a heuristic to handle large problems, that is, problems with a large number of possible cutting patterns.
Abstract: The two dimensional cutting problem consists of cutting a rectangular plate into specified smaller rectangular pieces, so that an objective function is optimized (for example, minimizing the waste). Different approaches and constraints for this problem have been considered by a number of authors. In particular, the unconstrained non-staged two-dimensional guillotine cutting problem was studied by Beasley(1985), who proposed a heuristic to handle large problems, that is, problems with a large number of possible cutting patterns. It is also possible to deal with large problems by imposing an artificial constraint of limiting the cuts to two stages. In this paper we consider both approaches, comparing their performance with some randomly generated examples.
19 citations
TL;DR: In this paper, the authors evaluated current thinking on business process reengineering (BPR) in the context of four schools of thought with respect to business strategy, with aspects of the management of change literatur...
Abstract: Current thinking on business process reengineering (BPR) is evaluated in the context of four schools of thought with respect to business strategy, with aspects of the management of change literatur...
19 citations
TL;DR: In this paper, the authors present three information and decision support systems which can be used to improve the availability and access to relevant data and information regarding the risk assessment associated with hazardous materials.
Abstract: This paper presents three information and decision support systems which can be used to improve the availability and access to relevant data and information regarding the risk assessment associated with hazardous materials. These systems offer quick and effective generation, display, analysis, evaluation and comparison of different alternatives. These alternatives involve technological environmental, socio-economic and political elements which are in a usable form of risk analysis.
TL;DR: In this article, two models for hazardous routing are briefly described and a condition is derived which, if satisfied, ensures that the linear model and the nonlinear model generate the same solution path, and if not satisfied, provides a strategy for obtaining the optimal solution.
Abstract: Two models for hazardous routing are briefly described. A condition is derived which, if satisfied, ensures that the linear model and the nonlinear model generate the same solution path, and if not satisfied, provides a strategy for obtaining the optimal solution to the nonlinear problem.
TL;DR: In this paper, a new methodology for business process reengineering is described, which builds on the experiences of organisations who have reengineered and also considers existing methodologies, and the experience of the author and some of his colleagues who have played a central role in a major reengineering project within British Telecommunications plc (BT).
Abstract: This paper describes a new methodology for Business Process Reengineering It builds on the experiences of organisations who have reengineered It also considers existing methodologies, and the experience of the author and some of his colleagues who have played a central role in a major reengineering project within British Telecommunications plc (BT) Though all “reengineering” consultancies undoubtably have methodologies for BPR, this paper reports an academically rigorous methodology which builds on the reported experiences of organisations, and views of leaders in the reengineering field
TL;DR: This paper presents the process developped for the selection of SWSF sites in French-speaking Switzerland, which is a multidisciplinary iterative approach that incorporates multicriteria decision making techniques like ELECTRE I.
Abstract: The search for sites to locate stabilised special waste storage facilities (SWSF) falls in the realm of hazardous/non-desirable facility location problems. The implementation of such projects is of...
TL;DR: In the 1990s, reengineering has become the preferred method of introducing major change and renewal in business practice as discussed by the authors, and much of the controversy surrounding reengineering stems from th...
Abstract: During the 1990s, reengineering has become the preferred method of introducing major change and renewal in business practice. Much of the controversy surrounding reengineering stems from th...
TL;DR: The service and inventory implications of this simple rule as a function of the parameters involved, in particular n and L, are investigated.
Abstract: In a consulting study for a major North American distributor it was observed that the materials manager had implemented a simple plausible method of establishing the reorder point of a stock keeping unit. Specifically, the demands in the last n periods (months) were observed. Then the current value of the reorder point was set as the maximum of these observations multiplied by the replenishment lead time (L) in periods, i.e., protection was provided against the situation where the maximum rate (observed in the last n periods) would occur throughout the entire lead time. In this paper we investigate the service and inventory implications of this simple rule as a function of the parameters involved, in particular n and L..
TL;DR: In this article, the authors advocate the use of location models to assess or even specify technologies for hazardous materials logistics, arguing that the existing technologies for toxic waste disposal have dictated the terms of the public debate and the evolution of our models.
Abstract: In this commentary, we advocate the use of location models to assess or even specify technologies for hazardous materials logistics. We argue that the existing technologies for toxic waste disposal — landfills and incinerators — have dictated the terms of the public debate and the evolution of our models. We then describe some alternative solar technologies for recycling toxic waste, with different implications for siting. Location science can be used proactively to envision how a new technology could restructure the spatial system dealing with toxic waste.
TL;DR: An approximate analysis of closed queueing networks where batch service and consequently batch arrivals are permitted is presented and the proposed approximation developed for multiple routing chains with load independent service rates is based on Mean Value Analysis (MVA) solution technique.
Abstract: The paper presents an approximate analysis of closed queueing networks where batch service and consequently batch arrivals are permitted. Bulk queueing systems arise naturally in many computer systems and computer communication contexts and may have a significant effect on system performance. Such systems present difficulties in analytic modeling because they violate the one step assumption which are essential to product form queueing networks. The proposed approximation developed for multiple routing chains with load independent service rates is based on Mean Value Analysis (MVA) solution technique. Simulation is employed to evaluate the accuracy of the method.
TL;DR: In 1995, the special issue of Infor on Hazardous Materials Logistics as discussed by the authors was published, where the authors presented a survey of the state-of-the-art in the field of information systems and operational research.
Abstract: (1995). Special Issue of Infor on Hazardous Materials Logistics. INFOR: Information Systems and Operational Research: Vol. 33, No. 2, pp. 65-67.
TL;DR: This work searches for efficient algorithms for solving RCP by reducing instances of RCP to known problems and applying solutions developed for them and extends the consensus procedure of Quine to solve RCP directly, ending up with three algorithms.
Abstract: GE Capital Services (GECS) has 80 million holders of private label credit cards that are regularly classified into homogeneous groups. For example, in collections millions of delinquent accounts are classified daily by attributes such as the amount owed and the number of months late in payment, and in marketing millions of accounts are classified daily according to the promotional material to be sent with the bills. A classification strategy specifies the mapping from accounts to groups based on the attributes of the accounts. A concise and powerful method of specifying a classification strategy is through the use of rules, which test account attributes and determine classification groups. A set of rules, however, can be inconsistent when one or more rules make another rule useless (we say that this rule is covered). The Rule Coverage Problem (RCP) is determining if any rule in a sequence of rules is covered.
We search for efficient (and possibly incomplete) algorithms for solving RCP (1) by reducing instances of RCP to known problems and applying solutions developed for them and (2) by extending the consensus procedure of Quine to solve RCP directly. We end up with three algorithms: one from reducing instances of RCP to instances of Co-SAT, which are solved using resolution; one from reducing instances of RCP to instances of Co-SAT, which are reduced to instances of the integer programming problem and solved using the simplex procedure; and one from solving RCP directly with the extended consensus procedure.
This work contributes theoretically, empirically, and commercially. Theoretically, several original problems with practical applications are introduced and solved using three diverse methods. For one method the consensus procedure of Quine is extended and applied to create efficient algorithms. Empirically, several diverse algorithms for solving subproblems of RCP are implemented and compared on GECS data. Commercially, a solution of RCP is ported to a PC and combined with a user interface to create two software products that are in full production use, improving GECS's collection and marketing efforts. With 80 million credit card holders, small decreases in losses (from collecting better) or small increases in sales (from marketing better) can significantly increase GECS's earnings.
TL;DR: In this article, the concept of reducing the feasible range of decision variables or fixing the value of the variables is extended for the knapsack problem to include sets of variables and the ease of fixing these variables is measured by a stability index.
Abstract: The concept of reducing the feasible range of decision variables or fixing the value of the variables is extended for the knapsack problem to include sets of variables. The ease of fixing these variables is measured by a stability index. The potential use of the concept is discussed in the context of approximation algorithms. Generalization to general zero-one problems is also considered.