Krystian Zorychta
University of Warsaw
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Computers & Operations Research | 1992
Włodzimierz Ogryczak; Krzysztof Studzinski; Krystian Zorychta
Abstract DINAS is an interactive system to aid solving various multiobjective transshipment problems with facility location using IBM-PC XT/AT or compatibles. DINAS utilizes the so-called aspiration-based (or reference point) approach to interactive handling of multiple objectives. In this approach the decision maker forms his/her requirements in terms of aspiration and reservation levels, i.e. specifies acceptable and required values for given objectives, whereas the system searches for a satisfying efficient solution by optimization of a special scalarizing achievement function. A sophisticated solver has been developed to provide DINAS with solutions to these single-objective problems. This numerical kernel of the system is, however, hidden from the user. Therefore the interactive analysis of the multiobjective problem can be performed with DINAS by a decision maker who is familiar with neither computer techniques nor mathematical programming.
European Journal of Operational Research | 1989
Włodzimierz Ogryczak; Krzysztof Studzinski; Krystian Zorychta
Abstract This paper describes the results of research, development and implementation of the Dynamic Interactive Network Analysis System (DINAS) which enables the solution of various multi-objective transshipment problems with facility location. DINAS utilizes an extension of the classical reference-point approach to handling multiple objectives. In this approach, the decision-maker (DM) forms his requirements in terms of aspiration and reservation levels, i.e., he specifies acceptable and required values for given objectives. For providing DINAS with solutions to single-objective problems, a special TRANSLOC solver was developed. It is based on the branch-and-bound scheme with a pioneering implementation of the simplex special ordered network (SON) algorithm with implicit representation of the VUB and SUB (variable and simple upper bound, respectively) constraints. A pilot version of the system is implemented on an IBM PC/XT microcomputer. DINAS is prepared as a menu-driven and easy-to-use system armed with a special network editor.
Computer Science and Operations Research#R##N#New Developments in their Interfaces | 1992
Włodzimierz Ogryczak; Krzysztof Studzinski; Krystian Zorychta
ABSTRACT This paper presents a network editor designed and implemented to provide an interactive optimization system for multiple criteria transshipment problems with a friendly tool for problem modification and solution examination. The essential data for a network problem can be divided into two groups: logical data defining a structure of the network (nodes and arcs), and numerical data describing characteristics of the nodes and arcs of the network (e.g., capacities, coefficients of the objective functions). The general concept of the presented network editor is to edit the numerical data with a window mechanism while examining or defining the logical structure of the network, i.e. while moving along the network.
Archive | 1989
Włodzimierz Ogryczak; Krzysztof Studzinski; Krystian Zorychta
DINAS is a scientific transferable software tool which enables the solution of various multiobjective transshipment problems with facility locations. For a given number of fixed facilities and customers and for a number of potential facilities to be optionally located, DINAS provides the user with a distribution pattern of a homogeneous product under a multicriteria optimality requirement. While working in an interactive mode, the user gets optimal locations of the potential facilities and a system of optimal flows of the product between nodes of the transportation network. With DINAS one can analyse and solve such problems as: the transportation problem with new supply and/or demand points location the problem of warehouses location the problem of stores location for the agricultural production the problem of service centers location and districts reorganization and many other real-life distribution-location problems.
Archive | 1989
Włodzimierz Ogryczak; Krzysztof Studzinski; Krystian Zorychta
DINAS is a decision support system which enables the solution of various multiobjective transshipment problems with facility location using IBM-PC XT/AT or compatibles. DINAS is prepared as a menu-driven and easy in usage system equipped with a special network editor which reduces to minimum effort associated with input a real-life problem. To illustrate the interactive procedure and the system capabilities we present in this paper using of DINAS to analyse a small testing example. As the test problem we use an artificial part of the real-life model connected with the health service districts reorganization.
Archive | 1989
Włodzimierz Ogryczak; Krzysztof Studzinski; Krystian Zorychta
This paper describes the Dynamic Interactive Network Analysis System (DINAS) which enables the solution of various multiobjective transshipment problems with facility location using IBM-PC XT/AT microcomputers. DINAS utilizes an extension of the classical reference point approach to handling multiple objectives. In this approach the decision-maker forms his requirements in terms of aspiration and reservation levels, i.e., he specifies acceptable and required values for given objectives. A special TRANSLOC solver was developed to provide DINAS with solutions to single-objective problems. It is based on the branch and bound scheme with a pioneering implementation of the simplex special ordered network (SON) algorithm with implicit representation of the simple and variable upper bounds (VUB & SUB). DINAS is prepared as a menu-driven and easy in usage system armed with a special network editor which reduces to minimum effort associated with input a real-life problem.
Archive | 1993
Włodzimierz Ogryczak; Krzysztof Studzinski; Krystian Zorychta
This paper describes a tutorial example for the Dynamic Interactive Network Analysis System (DINAS) which enables the solution of various multi-objective transshipment problems with facility location using IBM-PC microcomputers. The system utilizes an extension of the classical reference point approach to handling multiple objectives. DINAS is prepared as a menu-driven and easy to use system armed with a special network editor which reduces to minimum effort associated with defining real-life problems. As the tutorial problem we use an artificial part of the real-life model connected with a sugar-beet transshipment system.
ICCI'90 Proceedings of the international conference on Advances in computing and information | 1991
Włodzimierz Ogryczak; Krzysztof Studzinski; Krystian Zorychta
DINAS (Dynamic Interactive Network Analysis System) is an interactive system to aid in the solution of various multiobjective transportation problems with facility location. DINAS utilizes an extension of the reference point approach for interactive handling multiple objectives. In this approach the decision-maker forms his requirements in terms of aspiration and reservation levels, i.e., he specifies acceptable and required values for given objectives. A special solver was developed to provide DINAS with solutions to single-objective problems. It is based on the branch and bound scheme with a pioneering implementation of the simplex special ordered network (SON) algorithm with implicit representation of the simple and variable upper bounds (SUB & VUB). DINAS is prepared for IBM-PC XT/AT or compatibles as a menu-driven and easy in usage system equipped with a special network editor which reduces to minimum effort associated with data input for real-life problems.
Archive | 1989
Włodzimierz Ogryczak; Krzysztof Studzinski; Krystian Zorychta
This paper describes the methodological background of research performed at Warsaw University under the contracted study: “Theory, Software and Testing Examples for Decision Support Systems” supervised by the International Institute for Applied Systems Analysis (Ogryczak et al., 1987). The main goal of this work is development and implementation of the Dynamic Interactive Network Analysis System (DINAS) which enables the solution of various multiobjective transshipment problems with facility location using IBM PC/XT microcomputers. DINAS utilizes an extension of the classical reference point approach to handling multiple objectives. In this approach the decision-maker forms his requirements in terms of aspiration and reservation levels, i.e., he specifies acceptable and required values for given objectives. A special TRANSLOC solver was developed to provide DINAS with solutions to single-objective problems. It is based on the branch and bound scheme with a pioneering implementation of the simplex special ordered network (SON) algorithm with implicit representation of the simple and variable upper bounds (VUB & SUB).
Archive | 1989
Włodzimierz Ogryczak; Krzysztof Studzinski; Krystian Zorychta