This paper presented a web-based virtual system to simulate forging operation. The system utilized simulation techniques of Finite Element Method (FEM) to analyze the forging process and Virtual Reality Modeling Language (VRML) to visualize the simulation results in the web. The analysis using FEM could show mechanical information such as stresses and deformation profiles of a specimen during forging process and the analysis results were transferred into virtual space using VRML. Since the forging machine and specimen were modeled using Java and VRML, the forging machine and analysis results were browsed and integrated on the web that is interfaced to users through EAI to show the whole forging simulation. The developed system realized the working environment virtually so that education and experiment could be performed effectively even on the PC.

Production planning and control system plays an important role in manufacturing companies because it determines all production capacity planning, material procurement planning, and production scheduling which are needed in the process of producing products. Many researches on production planning and control system have been conducted for many manufacturing companies for recent decade. But, a considerable research achievement has mainly been obtained on the forecast-driven production for a make-to-stock and an assemble-to-order. The reason is that there are some hardships such as difficulties of standardizing product information, the frequent changes of design and material, and the unexpected dynamic events that influence the production of customer's order in a make-to-order or an engineering-to-order environments. By these characteristics and their complexities, some studies for production planning and control system in a make-to-order environment are presented recently. In this paper, we present the framework of the hietachical production planning and control for a make-to-order environment with dynamic events. In order to illustrate the usefulness of the proposed framework for a hietachical production planning and control, the information system for a make-to-order production was implemented with the object of the company of producing electricity transformer.

This paper presents a concurrent design approach that deals with manufacturing cell formation and cellular layout in Cellular Manufacturing System. Manufacturing cell formation is to group machines into machine cells dedicated to manufacture of part families, and cellular layout problem determines layout of the manufacturing cells within shop and layout of the machines within a cell. In this paper, a concurrent approach for design of machine cell and cellular layout is developed considering manufacturing parameters such as alternative process plans, alternative machines, production volume and processing time of part, and cost per unit time of operation. A mathematical model which minimizes total cost consisting of machine installation cost, machine operating cost, and intercell and intracell movements cost of part is proposed. A hybrid method based on genetic algorithm is proposed to solve the manufacturing cell formation and cellular layout design problem concurrently. The performance of the hybrid method is examined on several problems.

Logistics network management has become one of the most important sources of competitive advantage regarding logistics cost and customer service in numerous business segments. Logistics network simulation is a powerful analysis method for designing and planning the logistics network optimally in an integrated way. This paper introduces a logistics network simulator, LONSIM, developed by author. LONSIM deploys a mix of simulation and optimization functions to model and analysis logistics network issues such as facility location, inventory policy, manufacturing policy, transportation mode, warehouse assignment, supplier assignment, order processing priority rule, and vehicle routes. LONSIM is built with AweSim 2.1 and Visual Basic 6.0, and executed in windows environment.

The purpose of this paper is to develop a vehicle routing supporting system with various restrictions using a digital map. The position data and the distance data are obtained from the digital map. The system is composed of input module, execution module, output module. In the input module, we can select options, which correspond to various restrictions and criteria for the vehicle routing problem to be solved. The execution module solves the selected problem in a relatively short time and suggest a good heuristic solution to the dispatcher, and also allows the dispatcher to easily modify the solution. The vehicle routes are displayed on the digital map. The application and the effectiveness of the system were shown through two case studies.

This paper was studied to present a model for the application of AHP to the selection of airliners. For this study, a questionnaire was developed in respect to the criteria of airliner and given to 80 airline pilots and 30 maintenances in airlines to ask their opinions about the candidates for the middle-range airliners. The AHP software developed by Korean Advanced Institute of Science Technology (KAIST) was used to process the data. The result was analyzed by the criteria of selecting airliners and the several alternatives for the middle-range airliners.

In this study, we suggest a multi-generation Lotka-Volterra model, which is a competition model using game theory and complex system theory. The suggested model shows many improvements to weakness of a well known Bass model to forecast new technology in competitive markets. We show that the Lotka-Volterra model has strong power to forecast mobile communication services when it is used for competition of 1st generation mobile phone service and 2nd generation phone service in Korea. We finally use the model to forecast IMT-2000 service, the 3rd generation mobile communication service.

This paper introduces the case study that has been performed at the block paint shop, Hyundai Heavy Industries. First of all, the overall production processes of shipbuilding and research activities conducted by Korean are reviewed with a view-point of production planning. Then HYPOS(Hyundai heavy industries Painting shop Operation System) project is briefly described, which has several modules such as planning module, scheduling module, work order module, and DB(database) management module. Although the HYPOS system has several modules, this paper mainly focuses on the planning module that utilizes the rough-cut simulation algorithm to make a decision about the policy for production schedule. The HYPOS has been operated since June, 2000 and the operation data has been collected for the purpose of future evaluation about the performance of HYPOS system. The evaluation of HYPOS will be shown in a public domain as soon as the enough operation data is available.

This paper describes the simulation study which estimates the container crane efficiency in container terminal. In most simulation studies, it is assumed that container cranes are available at any time. Though the failures of container cranes don't occur often, they are very serious problems on terminal efficiency. As usual, the failures of container crane cause arrived ships to delay the departure time. In this study, a queueing simulation model for container terminal, which focuses on the failures of container cranes, is designed. The simulation approach appears to be the most appropriate one because it allows to avoid the usual exponential assumption on interarrivals of ships and service times of container cranes. Using the developed model, we tested the efficiency of container cranes considering failures with a real system size and performed the simulation experiment on real container terminal to validate the developed simulation model. The results of simulation experiment were analyzed using output statistics, which include the waiting times of vessels and yard tractors, the utilization for container cranes, and the berth occupancy rates.

In this paper, we propose a simple method to reduce categorical variables into smaller, but significant numbers, and also demonstrate how the proposed method can be applied to the problem of reduction that empirical research often faces in the course of data processing. For the purpose, we introduce a concept of pseudo-correlation coefficient to make it possible to use factor analysis (FA) as a tool for reducing variables. The main idea of the concept is to deal with the measures of association of categorical variables in the sense of the concept of Pearson's correlation coefficient in order to meet the input requirement of FA. Upon examination of existing measures that could play as pseudo-correlation coefficients, Cramer's V coefficient is selected for the best result among them. To show the detailed procedure of the proposed method, a specific demonstration with the data from 329 R&D projects conducted in 18 private laboratories in electric and electronics industry is presented.

Through the use of internet, a new trend of business which is now known as electronic commerce has emerged. Although the importance of shopping mall design has been mentioned frequently, empirical study towards the design factors has been scarcely carried. The purpose of this study is to identify the relationship between the design factors of a shopping mall and the user characteristics. Result showed that there is a significant relationship between the some design factors of shopping mall and user characteristics. Especially the users of internet shopping mall those who have used the web frequently tend to dislike the diverse use of complex fonts, bold, or italics. The result of this paper can give some ideas to the people who are designing a shopping mall and company who tries to construct a shopping mall.

Previous work measurement methods need much time and effort of time study analysts because they have to measure required time through direct observations. In this study, we propose a method which efficiently measures standard times without involvement of human analysts using digital image processing techniques. This method consists of two main steps: motion representation step and cycle segmentation step. In motion representation step, we first detect the motion of any object distinct from its background by differencing two consecutive images separated by a constant time interval. The images thus obtained then pass through an edge detector filter. Finally, the mean values of coordinates of significant pixels of the edge image are obtained. Through these processes, the motions of the observed worker are represented by two time series data of worker location in horizontal and vertical axes. In the second step, called the cycle segmentation step, we extract the frames which have maximum or minimum coordinates in one cycle and store them in a stack, and calculate each cycle time using these frames. In this step we also consider methods on how to detect work delays due to unexpected events such as operator's escapement from the work area, or interruptions. To condude, the experimental results show that the proposed method is very cost-effective and useful for measuring time standards for various work environment.

The importance of development of occupational safety index is truly great. It will contribute to the wise direction of safety program. In present, frequency and severity ratios were the standard measure. These terms express the incidence of major injuries and severity of the major injuries experience, each with relation to the employee-hours of work exposure during the period that is measured. But these measure don't expressed the dangerous feeling degree of worker. In this study, Effective Industrial Safety Index(EISI) was developed using dangerous feeling degree of worker, frequency of injuries, and severity of injury. EISI can be used as an aid for effective safety management in workplace.