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The article presents information on a method or algorithm for finding proposals on which all members of a group can agree. The method is confined to situations where the variables can be changed by any "small" amount and, where the group is attempting to decide on a change in the variables from some "existing situation." A possible change in the variables will be called a "proposal." A proposal would be "acceptable" to an individual if it would increase his utility. The problem is not to pick a particular proposal which is acceptable to all individuals.

"Pattern recognition" is a field of techniques for distinguishing significant phenomena, for determining on the whether a phenomenon is a known type or into a number of groups, etc. cybernetics which develops common properties of some basis of these properties not, for clustering phenomena into a number of groups, etc. Pattern is a name of a set of objects or phenomena distinguished according to a specific problem, bearing resemblance to each other and differing from the objects of other sets. Depending on the specific objective of the research one and the same pair of objects may be related to one pattern or to different ones. The hypothesis of "the simplicity of structural regularities" assumes the construction of a decision rule describing special features in the structure of the set of points in the given pattern. The points may be by no means "solidly" beside each other, but if there is some regularity in their array it should attract the attention. In order to secure the regularity against the influence of arbitrariness because of choosing scales of devices which measure properties, the isomorphism between the considered system with relations and the numerical model of this system is required.

The general problem of interdisciplinary relations and transdisciplinary integration has its counterpart in the field of education in the problem of producing generalists rather than specialists, and at the undergraduate college level, in the problem of devising a rational core curriculum. At present, neither the student nor the faculty knows why one mixture of courses is better or worse than another. This paper advocates a solution to this problem based on the development of a computerized model of the core curriculum in which the interrelated mutually relevant concepts of various disciplines would be associated with teaching time allocations proportional to their degree of conceptual relevance. The foundation for such a development is laid by a discussion of conceptual vs. personal relevance, of acculturation vs. exculturation, of education vs. instruction, and of immediate vs. delayed motivation. An algorithmic procedure is then outlined which would result in a dynamic model allowing the determination of educational bottlenecks or critical paths in the communication network transforming inputs into outputs. The general concepts of dynamic programming, program evaluation and review techniques, system and decision theory are used in developing the algorithm. The existence of such a model would allow a rational optimization of the curriculum and would make the present perennial trial-and-error experimentation in curriculum design unnecessary, since the computer could test various alternatives quickly and efficiently. [ABSTRACT FROM AUTHOR]

A specialized neurosurgical data acquisition and processing system was developed and applied in practice to monitor some 60 patients after head injury or neurosurgical operations. At first the system allowed off-line operation, and the experiences thus gained made it possible to implement the system in its present form for real-time online patient monitoring. The algorithms prepared in our laboratory allow rapid and concise presentation of results and have proved their usefulness in clinical practice. The main parameters of interest in neurosurgery are intracranial pressure (ICP) and the volume of cerebrospinal fluid (CSF) drained from one of the lateral ventricles. Examples of statistical analysis of both these variables, and their presentation in the form of tables, diagrams and histograms are given. [ABSTRACT FROM AUTHOR]

In large disaggregated input-output tables the conventional practice of triangularizied hierarchy of industries may not always work. Very often there are sets of industries which are mutually related by backward and forward linkages such that they represent coherent groups that are unrelated to the remaining industries in terms of transactions taking place in the input-output tables. To identify such coherent sets or blocks of industries which we call 'industrial complexes' in the input-output tables has been the major objective of this paper. An algorithm is designed to meet this objective that also avoids the irrelevance and complications of the multivariate analyses that are usually applied to such a search. Some empirical tests are then performed to discover the industrial complexes from the input-output tables of Canada, 1961 and 1966, and the US, 1963. [ABSTRACT FROM AUTHOR]

This note describes the application of the variable projection (VP) algorithm developed by Golub and Pereyra [1973], and successively modified by Krogh [1974] and Kaufman [1975] to the iterated generalized least squares estimation of nonlinear systems of equations whose parameters separate into a linear part and a nonlinear part. The VP algorithm was originally applied to the least squares estimation of single-equation models having this structure. Recently an extension has been proposed [Corradi] for the estimation of seemingly unrelated nonlinear regressions, which has proved to be computationally more efficient than the standard methods as employed e.g. in Gallant [1975]. In Section 1 we outline the proposed computational procedure and examine its relevant features, while in Section 2 we present some numerical results. [ABSTRACT FROM AUTHOR]

In a recent paper McCormick and Ritter consider two classes of algorithms, namely methods of conjugate directions and quasi-Newton methods, for the problem of minimizing a function of n variables F(x). They show that the former methods possess an n-step superlinear rate of convergence while the latter are every step superlinear and therefore inherently superior. In this paper a simple and computationally inexpensive modification of a method of conjugate directions is presented. It is shown that the modified method is a quasi-Newton method and is thus every step superlinearly convergent. It is also shown that under certain assumptions on the second derivatives of F the rate of convergence of the modified method is n-step quadratic. [ABSTRACT FROM AUTHOR]

A variable dimension algorithm is presented for the linear complementarity problem s − Mz = q; s,z ≥ 0; s z = 0 for i = 1,2, ⋯ , n. The algorithm solves a sequence of subproblems of different dimensions, the sequence being possibly nonmonotonic in the dimension of the subproblem solved. Every subproblem is the linear complementarity problem defined by a leading principal minor of the matrix M. Index-theoretic arguments characterize the points at which nonmonotonic behavior occurs. [ABSTRACT FROM AUTHOR]

Copyright of Computing is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Computing is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Computing is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Computing is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Although the first multidimensional scaling algorithms developed were metric algorithms, the development of non-metric methods led to a rapid and nearly complete abandonment of the metric procedures in favor of these newer algorithms. Recently, however, there has been a resurgence of interest in metric algorithms, particularly within the field of human communication research, where the use of metric procedures predominates. In order to understand this reversion to what many psychometricians believe to be an outdated technique it is necessary to understand the difficulties and philosophy, which led to the increased interest in metric scaling. While there is little doubt that the development of non-metric multidimensional scaling algorithms represents a great advance in the methods available to the contemporary social scientist, there exist some areas of inquiry in which the metric scaling routines may offer certain advantages. This article discusses one such case, familiar to communication researchers in particular. The article shows that the Riemannian character of the spatial configurations resulting from these methods cannot be attributed solely to unreliability of measurement.

The article presents abstracts of several articles and research papers that appeared in the December 1982 issue of the journal Quality and Quantity. An article authored by Joseph Woelfel and George A. Barnett examines the imaginary dimensions, which may result from metric multidimensional scaling of pairwise comparison data. A non-Euclidean solution results because the dissimilarity matrix entered into the scaling algorithm is non-positive semidefinite. Authors first discuss the reliability and predictive validity of these dimensions and then provide theoretical interpretations for their existence. The article offers two alternative interpretations for the imaginary dimensions. Another article by Lily Neumann states that in the construction of a rating scale in attitude and satisfaction questionnaires, a common issue concerns the number of rating categories to use. The effects of grouping on the correlation coefficient have been examined for several bivariate distributions-uniform, normal, logistic and exponential. Another paper presents a property-space perspective for handling interaction terms in statistical models.

We address several issues that are raised by Bentler and Tanaka's [1983] discussion of Rubin and Thayer [1982]. Our conclusions are: standard methods do not completely monitor the possible existence of multiple local maxima; summarizing inferential precision by the standard output based on second derivatives of the log likelihood at a maximum can be inappropriate, even if there exists a unique local maximum; EM and LISREL can be viewed as complementary, albeit not entirely adequate, tools for factor analysis. [ABSTRACT FROM AUTHOR]

Copyright of Computing is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Epicardial mapping is an important method for locating the accurate portion of the accessory pathway. Mapping is usually executed by measuring the time of the major deflection (the activation time) between two electrodes about 1 mm apart. The epicardial isochrone map is made up of contour lines connecting points with an equal activation time on the epicardium. The paper describes a newly developed microcomputer-based system for drawing epicardial isochrone maps. In this system, a simplified algorithm is introduced to extract the excitation delay from intracardiac reference signals and epicardial activation signals. By applying the B-Spline function to drawing the excitation map, an excitation pattern which is similar to the original is, obtained for each standard excitation pattern. [ABSTRACT FROM AUTHOR]

The goal is to give some theoretical explanation for the efficiency of the simplex method of George Dantzig. Fixing the number of constraints and using Dantzig's self-dual parametric algorithm, we show that the number of pivots required to solve a linear programming problem grows in proportion to the number of variables on the average. [ABSTRACT FROM AUTHOR]

Copyright of Computing is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents a list of articles related to randomized algorithms published in several periodicals. The articles include "Two Theorems on Random Polynomial Time," by L. Adleman, "On a Primality Test of Solovay and Strassen," by A. O. L. Atkin and R. G. Larson, "On the Frequency Solution of Algorithmically Unsolvable Mass Problems," by J. M. Barzdin," and "Factoring Polynomials Over Large Finite Fields," by E. R. Berlekamp.

Copyright of Computing is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Proximity data are very common in the behavioral sciences. A review of procedures for gathering similarity or dissimilarity data can be found in J.B. Kruskal, M. Wish and E.E. Roskam. Often a set of proximity data is incomplete. Dissimilarity data are usually analyzed by means of multidimensional scaling or hierarchical clustering. More recently, additive trees have been used for representing proximity data. Dissimilarity data are usually analyzed by means of multidimensional scaling or hierarchical clustering. More recently, additive trees have been used for representing proximity data. Researchers found that additive trees can give a better account of proximities between conceptual stimuli than multidimensional scaling. Since they do not require the data to satisfy the ultrametric inequality, additive trees are less restrictive than most hierarchical-clustering models. The Monte Carlo results obtained show that for complete data the algorithm is quite insensitive to the choice of the initial parameter estimates.

Copyright of Computing is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Computing is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Let P and Q be two convex polygons with m and n vertices, respectively, which are specified by their cartesian coordinates in order. A simple O(m+n) algorithm is presented for computing the intersection of P and Q. Unlike previous algorithms, the new algorithm consists of a two-step combination of two simple algorithms for finding convex hulls and triangulations of polygons. [ABSTRACT FROM AUTHOR]

Focuses on the operations research for the development of algorithms and software for optimization problems. Emphasis of combinatorial optimization on problems motivated by routing and scheduling problems; Presentation of a survey on the area of interactive optimization; Explanation on how optimization can be combined with the popular spreadsheet programs for microcomputers.

The inventory routing problem is a distribution problem in which each customer maintains a local inventory of a product such as heating oil and consumes a certain amount of that product each day. Each day a fleet of trucks is dispatched over a set of routes to resupply a subset of the customers. In this paper, we describe and compare algorithms for this problem defined over a short planning period, e.g. one week. These algorithms define the set of customers to be serviced each day and produce routes for a fleet of vehicles to service those customers. Two algorithms are compared in detail, one which first allocates deliveries to days and then solves a vehicle routing problem and a second which treats the multi-day problem as a modified vehicle routing problem. The comparison is based on a set of real data obtained from a propane distribution firm in Pennsylvania. The solutions obtained by both procedures compare quite favorably with those in use by the firm. [ABSTRACT FROM AUTHOR]

This paper develops certain sensitivity analysis capabilities for use with a primal-dual matching code. The specific problem addressed is reoptimizing after the costs of a subset of the edges have been increased by a constant amount. This capability is applied to a dual ascent procedure for a Lagrangian relaxation of a matching problem with a single generalized upper bound side constraint. Some of the sensitivity analysis capabilities should be useful in other contexts as well. In particular, we give a method for solving for a set of dual variables that satisfy the strong complementary conditions given a blossom structure. [ABSTRACT FROM AUTHOR]

In this paper we discuss the shortest augmenting path method for solving assignment problems in the following respect: — we introduce this basic concept using matching theory; — we present several efficient labeling techniques for constructing shortest augmenting paths; — we show the relationship of this approach to several classical assignment algorithms; — we present extensive computational experience for complete problems, and — we show how postoptimal analysis can be performed using this approach and naturally leads to a new, highly efficient hybrid approach for solving large-scale dense assignment problems. [ABSTRACT FROM AUTHOR]

We review the Lawler-Murty [24,20] procedure for finding the JC best solutions to combinatorial optimization problems. Then we introduce an alternative algorithm which is based on a binary search tree procedure. We apply both algorithms to the problems of finding the K best bases in a matroid, perfect matchings, and best cuts in a network. [ABSTRACT FROM AUTHOR]

In the last years, decomposition techniques have seen an increasing application to the solution of problems from operations research and combinatorial optimization, in particular in network theory and graph theory. This paper gives a broad treatment of a particular aspect of this approach, viz. the design of algorithms to compute the decomposition possibilities for a large class of discrete structures. The decomposition considered is the substitution decomposition (also known as modular decomposition, disjunctive decomposition, X-join or ordinal sum). Under rather general assumptions on the type of structure considered, these (possibly exponentially many) decomposition possibilities can be appropriately represented in a composition tree of polynomial size. The task of determining this tree is shown to be polynomially equivalent to the seemingly weaker task of determining the closed hull of a given set w.r.t. a closure operation associated with the substitution decomposition. Based on this reduction, we show that for arbitrary relations the composition tree can be constructed in polynomial time. For clutters and monotonic Boolean functions, this task of constructing the closed hull is shown to be Turing-reducible to the problem of determining the circuits of the independence system associated with the clutter or the prime implicants of the Boolean function. This leads to polynomial algorithms for special clutters or monotonic Boolean functions. However, these results seem not to be extendable to the general case, as we derive exponential lower bounds for oracle decomposition algorithms for arbitrary set systems and Boolean functions. [ABSTRACT FROM AUTHOR]

The paper deals with the network optimization problem of minimizing regular project cost subject to an arbitrary precedence relation on the sets of activities and to arbitrarily many resource constraints. The treatment is done via a purely structural approach that considerably extends the disjunctive graph concept. It is based on so-called feasible posets and includes a quite deep and useful representation theorem. This theorem permits many insights concerning the analytical behaviour of the optimal value function, the description and counting of ail essentially different optimization problems, the nature of Graham anomalies, connections with the online stochastic generalizations, and several others. In addition, it also allows the design of a quite powerful class of branch-and-bound algorithms for such problems, which is based on an iterative construction of feasible posets. Using so-called distance matrices, this approach permits the restriction of the exponential part of the algorithm to the often comparatively small set of ‘resource and cost essential’ jobs. The paper reports on computational experience with this algorithm for examples from the building industry and includes a rough comparison with the integer programming approach by Talbot and Patterson. [ABSTRACT FROM AUTHOR]

A common problem frequently faced by business firms and individual investors is to select a few investment opportunities from many available possibilities. This problem, in its simplest form, can be modeled as a O-l knapsack problem. In a more general investment scenario, however, we obtain a model which is a general knapsack problem with a multiple-choice constraint. To solve this problem, an efficient enumerative algorithm is developed. The algorithm includes an efficient procedure to solve the LP-relaxed problem, a reduction algorithm which may allow the initial fixing of some of the variables, and various other implicit enumeration criteria derived from the group problem. Extensive computational experience illustrates the efficiency of the algorithm and related results. [ABSTRACT FROM AUTHOR]

We develop local search algorithms for routing problems with time windows. The presented algorithms are based on the k-interchange concept. The presence of time windows introduces feasibility constraints, the checking of which normally requires O(N) time. Our method reduces this checking effort to O(1) time. We also consider the problem of finding initial solutions. A complexity result is given and an insertion heuristic is described. [ABSTRACT FROM AUTHOR]

A new zero-one integer programming model for the job shop scheduling problem with minimum makespan criterion is presented. The algorithm consists of two parts: (a) a branch and bound parametric linear programming code for solving the job shop problem with fixed completion time; (b) a problem expanding algorithm for finding the optimal completion time. Computational experience for problems having up to thirty-six operations is presented. The largest problem solved was limited by memory space, not computation time. Efforts are under way to improve the efficiency of the algorithm and to reduce its memory requirements. [ABSTRACT FROM AUTHOR]

Animators frequently use paint systems to create and refine their images. In such a program, an artist creates a brush that is moved across a frame buffer, providing a simplified simulation of a physical brush moving across an actual canvas. Movement of the brush often requires modification of a large number of pixels in a small amount of time. Existing algorithms for brush movement are discussed, and two new algorithms are presented that reduce the amount of i/o needed to move a brush, but at the expense of increased computational complexity. [ABSTRACT FROM AUTHOR]

Polynomial regression, long known to provide an approach to curvilinear analyses, is limited by its inability to provide clearly interpretable results as required by disciplines such as sociology. First, as social scientist J.A. Stimson emphasize, any attempt to attach meaning in the sense of partial effects of the polynomial terms is nonsensical. Second, when polynomial regression is used in sociological explanation, the absolute contribution of each term in the equation becomes critical. With ordinary polynomial regression, the multicollinearity is of such magnitude that it is usually not possible to obtain stable estimates of each variable's contribution. This paper demonstrates the limitations of the translation technique and presents a straightforward algorithm for its application when appropriate. A special form of the polynomial is then developed which, for specific shapes of the function, can estimate a polynomial of any degree without encountering the problems which have limited application of the polynomial to both theory and measurement models.

We present a general active set algorithm for the solution of a convex quadratic programming problem having a parametrized Hessian matrix. The parametric Hessian matrix is a positive semidefinite Hessian matrix plus a real parameter multiplying a symmetric matrix of rank one or two. The algorithm solves the problem for all parameter values in the open interval upon which the parametric Hessian is positive semidefinite. The algorithm is general in that any of several existing quadratic programming algorithms can be extended in a straightforward manner for the solution of the parametric Hessian problem. [ABSTRACT FROM AUTHOR]

This paper describes the formulation of a nonlinear mixed integer programming model for a large-scale product development and distribution problem and the design and computational implementation of a special purpose algorithm to solve the model. The results described demonstrate that integrating the art of modeling with the sciences of solution methodology and computer implementation provides a powerful approach for attacking difficult problems. The efforts described here were successful because they capitalized on the wealth of existing modeling technology and algorithm technology, the availability of efficient and reliable optimization, matrix generation and graphics software, and the speed of large-scale computer hardware. The model permitted the combined use of decomposition, general linear programming and network optimization within a branch and bound algorithm to overcome mathematical complexity. The computer system reliably found solutions with considerably better objective function values 30 to 50 times faster than had been achieved using general purpose optimization software alone. Throughout twenty months of daily use, the system was credited with providing insights and suggesting strategies that led to very large dollar savings. [ABSTRACT FROM AUTHOR]

This paper considers basis construction in a linear program when the number of activities with basic status is not equal to the number of rows in the particular scenario. This arises when starting with an ‘advanced basis’, obtained from a solution to another scenario. The goal here is to provide a triangular-seeking algorithm that takes advantage of structural properties during the construction of a basis agenda. For completeness, some facts, which are known but have not been published, are given about choosing an advanced basis and about spikes. [ABSTRACT FROM AUTHOR]

In this paper, an algorithm is presented for the transshipment problem that is an adaption of the method used by Jones, Saigal, and Schneider for solving single-commodity, spatial-equilibrium problems. The approach uses a variable-dimension strategy in which a sequence of subproblems is formed by solving the problem ‘one-node-at-a-time’. The algorithm is tested on uncapacitated transportation problems. Although the computational results are not directly comparable to other methods (since the algorithm is implemented in C under UNIX), the results show that the method is very effective and may be competitive with the best available algorithms for linear network problems. [ABSTRACT FROM AUTHOR]

This paper is concerned with computational experimentation leading to the design of effective branch and bound algorithms for an important class of nonlinear integer programming problems, namely linearly constrained problems, which are used to model several real-world situations. The main contribution here is a study of the effect of node and branching variable selection and storage reduction strategies on overall computational effort for this class of problems, as well as the generation of a set of adequate test problems. Several node and branching variable strategies are compared in the context of a pure breadth-first enumeration, as well as in a special breadth and depth enumeration combination approach presented herein. Also, the effect of using updated pseudocosts is briefly addressed. Computational experience is presented on a set of eighteen suitably-sized nonlinear test problems, as well as on some random linear integer programs. Some of the new rules proposed are demonstrated to be significantly superior to previously suggested strategies; interestingly, even for linear integer programming problems. [ABSTRACT FROM AUTHOR]

Gauss-Seidel type relaxation techniques are applied in the context of strictly convex pure networks with separable cost functions. The algorithm is an extension of the Bertsekas-Tseng approach for solving the linear network problem and its dual as a pair of monotropic programming problems. The method is extended to cover the class of generalized network problems. Alternative internal tactics for the dual problem are examined. Computational experiments - aimed at the improved efficiency of the algorithm - are presented. [ABSTRACT FROM AUTHOR]

Optimization algorithms or heuristics in which the user interacts significantly either during the solution process or as part of post-optimality analysis are becoming increasingly popular. An important underlying premise of such man/machine systems is that there are some steps in solving a problem in which the computer has an advantage and other steps in which a human has an advantage. This paper first discusses how man/machine systems can be useful in facilitating model specification and revision, coping with aspects of a problem that are difficult to quantify and assisting in the solution process. We then survey successful systems that have been developed in the areas of vehicle scheduling, location problems, job shop scheduling, course scheduling, and planning language-based optimization. [ABSTRACT FROM AUTHOR]

Copyright of Computing is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A comprehensive functional assessment requires thorough and careful inquiry, which is difficult to accomplish in most busy clinical practices. This paper examines the reliability and validity of the Functional Status Questionnaire (FSQ), a brief, standardized, self-administered questionnaire designed to provide a comprehensive and feasible assessment of physical, psychological, social and role function in ambulatory patients. The FSQ can be completed and computer-scored in minutes to produce a one-page report which includes six summated-rating scale scores and six single-item scores. The clinician can use this report both to screen for and to monitor patients' functional status. In this study, the FSQ was administered to 497 regular users of Boston's Beth Israel Hospital's Healthcare Associates and 656 regular users of 76 internal medicine practices in Los Angeles. The data demonstrate that the FSQ produces reliable sub-scales with construct validity. The authors believe the FSQ addresses many of the problems behind the slow diffusion into primary care of systematic functional assessment. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to review some of the many instances in which a location analyst must make a decision as to where an obnoxious facility should be placed. An obnoxious facility is one that can be defined as a facility which has undesirable interactions with existing facilities. Examples include equipment which emit pollutants such as particulates, noise and radiation or warehouses that contain flammable materials. Other obnoxious facilities include machines that are potential sources of hazards to nearby machines and workers. The interaction between the obnoxious facility and each existing facility is reflected through a weighting factor. The feasible region is considered to be continuous in the form of a convex or nonconvex simple polygon. Since the new facility is to be located away from the existing facilities, an appropriate criterion for optimization is the MAXIMIN or the MAXISUM criterion. Algorithms are reviewed for two common metrics under both criteria, i.e. Euclidean and rectilinear. [ABSTRACT FROM AUTHOR]

Classical location theories and models were initially developed for the private sector, so that the related operational research literature has emphasized performance measures of efficiency and effectiveness. For public sector applications, measures of equity become important, yet such measures have received little formal treatment. This paper suggests a locational equity measure, the variance measure, and investigates its properties for tree networks. A fast algorithm (O(M)) to locate the minimum variance point on a tree network is developed, and some numerical results illustrate the variance optimal location. [ABSTRACT FROM AUTHOR]

In location-routing problems, the objective is to locate one or many depots within a set of sites (representing customer locations or cities) and to construct delivery routes from the selected depot or depots to the remaining sites at least system cost. The objective function is the sum of depot operating costs, vehicle acquisition costs and routing costs. This paper considers one such problem m which a weight is assigned to each site and where sites are to be visited by vehicles having a given capacity. The solution must be such that the sum of the weights of sites visited on any given route does not exceed the capacity of the visiting vehicle. The formulation of an integer linear program for this problem involves degree constraints generalized subtour elimination constraints, and chain baring constraints. An exact algorithm, using initial relaxation of most of the problem constraints, is presented which is capable of solving problems with up to twenty sites within a reasonable number of iterations [ABSTRACT FROM AUTHOR]