Thomas A. Barta

Modeling and analysis of a manufacturing cell formation problem with fuzzy mixed-integer programming

Cell formation (CF) has received much attention from academicians and practitioners because of its strategic importance to modern manufacturing practice. In this paper a sophisticated mixed-integer programming (MIP) model is proposed to simultaneously form manufacturing cells and minimize the cost of dealing with exceptional elements. Also, we illustrate how a fuzzy mixed-integer programming (FMIP) approach can be used to solve the CF problem in a fuzzy environment, propose a new fuzzy operator, and examine the impact of different membership functions and operators on computational performance. Our study shows that FMIP not only provides a better and more flexible way of representing the problem domain, it also leads to improved overall performance.

A Petri net-based simulation tool for the design and analysis of flexible manufacturing systems

Abstract Simulation is an invaluable tool in designing and analyzing manufacturing systems. A Petri net-based simulation tool is presented to aid simulation projects in manufacturing, including flexible manufacturing systems (FMSs). Three models are developed—an object model, Petri net model, and control model. While hardware components of FMSs are modeled by Petri net objects, control functions are separately modeled and integrated with a Petri net model to resolve conflicts occurring in Petri net execution. Facilities of the developed tool are presented, and a modeling procedure with the tool is illustrated via a case study.

Fuzzy linear programming approach to manufacturing cell formation

Modeling real world problems precisely is a very difficult task as most of the objective and constraints cannot be precisely defined and the data is either unavailable or indeterminate. Fortunately, this type of problem can be solved efficiently via fuzzy mathematical programming. This paper illustrates how a fuzzy linear programming approach be used to model and solve cell formation (CF) problems. We also examined different membership functions to see their impacts on the computational performance. This study reveals that representing the CF problem using fuzzy set theory not only is a clever and flexible choice, it also can lead to improve the overall performance.<<ETX>>

A quantitative comparison of three simulation languages: SLAM, GPSS/H, SIMSCRIPT

Abstract Three simulation languages are quantitatively compared in a manufacturing job shop environment. Both model size and model run length were varied to obtain data on compilation time, execution time. CPU time, memory time and the rate of change of these variables due to changes in the simulation period.

A case-based reasoning system for housing discrimination law

Abstract A case-based reasoning system was developed for housing discrimination laws that is general enough for other applications. The knowledge base consists of previously decided housing discrimination court cases presented as templates. Events in each case are represented as patterns of actions weighted for importance. New cases are matched with old using a pattern detection mechanism. Adaptation of the old case to the new is then based on certainty factor algebra.

Placing a Value on Human-Resources: A Markov Approach

Abstract A method of placing a monetary value on the human resources of an organization is explained. The purpose is to improve the quality of managerial decisions that concern people. Markov approaches, both stationary and time-varying, are used in combination with life analysis, a technique useful in industrial property valuation. This application illustrates a use of the modern theory of Markov chains utilizing stopping times.

Animated simulation graphics for a manufacturing conveyor system

Abstract Computer simulation is an important aid for designing manufacturing systems. Computer graphics is an extremely effective medium for communication between man and computer. Because animated simulation graphics is a field whose time has come, the study described herein uses a combination of computer simulation and computer graphics in the designing of a complex manufacturing conveyor system.