• Journal of KIISE:Computer Systems and Theory
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• v.29 no.6
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• pp.361-368
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• 2002

This paper presents a new data path synthesis algorithm which takes into account simultaneously three important design criteria: testability, design area, and total execution time. We define a goodness measure on the testability of a circuit based on three rules of thumb introduced in prior work on synthesis for testability. We then develop a stepwise refinement synthesis algorithm which carries out the scheduling and allocation tacks in an integrated fashion. Experimental results for benchmark and other circuit examples show that we are able to enhance the testability of circuits with very little overheads on design area and execution time.

• International Journal of Precision Engineering and Manufacturing
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• v.4 no.2
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• pp.71-76
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• 2003

A virtual machine tool (VMT) is presented in this two-part paper. In Part 1, the analytical foundation for a virtual machining system is developed, which is envisioned as the foundation for a comprehensive simulation environment capable of predicting the outcome of cutting processes. The VHT system undergoes "pseudo-real machining", before actual cutting with a CNC machine tool takes place, to provide the proper cutting conditions for process planners and to compensate or control the machining process in terms of the productivity and attributes of the products. The attributes can be characterized by the machined surface error, dimensional accuracy, roughness, integrity, and so forth. The main components of the VMT are the cutting process, application, thermal behavior, and feed drive modules. In Part 1, the cutting process module is presented. When verified experimentally, the proposed models gave significantly better prediction results than any other methods. In Part 2 of this paper, the thermal behavior and feed drive modules are developed, and the models are integrated into a comprehensive software environment.vironment.

• Korean Management Science Review
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• v.18 no.2
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• pp.125-134
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• 2001

This paper is concerned with the development of a GIS-based distribution system with service consideration. The proposed model could be used for a wide range of logistics applications in planning, engineering and operational purpose for logistics system. This research addresses the formulation of those complex prob1ems of two-echelon logistics system to plan the incorporating supply center locations and distribution problems based on GIS. We propose an integrated logistics model for determining the optimal patterns of supply centers and inventory allocations (customers) with a three-step sequential approach. 1) First step, Developing GIS-distance model and stochastic set-covering program to determine Optimel pattern of supply center location. 2) Second step, Optimal sector-clustering to support customers. 3) Third step, Optimal vehicle rouse scheduling based on GIS, GIS-VRP In this research we developed GUI-tree program, the GIS-VRP provide the vehicle to users and freight information in real time. We applied a set of sample examples to this model and demonstrated samp1e results. It has been found that the proposed model is potentially efficient and useful in solving multi-depot problem through examples. However the proposed model can provide logistics decision makers to get the best supply schedule.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.11
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• pp.74-79
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• 2001

In this two-part paper, a virtual machine tool (VMT) is presented. In part 1, the analytical foundation of a virtual machining system, envisioned as the foundation for a comprehensive simulation environment capable of predicting the outcome of cutting processes, is developed. The VMT system purposes to experience the pseudo-real machining before real cutting with a CNC machine tool, to provide the proper cutting conditions for process planners, and to compensate or control the machining process in terms of the productivity and attributes of products. The attributes can be characterized with the machined surface error, dimensional accuracy, roughness, integrity and so forth. The main components of the VMT are cutting process, application, thermal behavior and feed drive modules. In part 1, the cutting process module is presented. The proposed models were verified experimentally and gave significantly better prediction results than any other method. The thermal behavior and feed drive modules are developed in part 2 paper. The developed models are integrated as a comprehensive software environment in part 2 paper.

• Journal of the Korea Society of Computer and Information
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• v.1 no.1
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• pp.147-158
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• 1996

This paper proposed a concurrency control structure based on specialized data flow graphs that was analysed a run-time concurrency control activity to be integrated with the task scheduler Data were viewed as flowing on the arcs from one node to another in a stream of discrete to tokens. The network that Is based upon the Entity-Relationship model, can be viewed a fixed problems used query tokens as a data flow graph. The performance was measured used in the various expriments compared the overall performance of the different concurrency control methods, DBFG (DataBase Flow graphs) scheduling had the knowledge to obtain better performance than 2PL in a distributed environment.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.57 no.2
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• pp.202-208
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• 2008

Condition monitoring technologies allow achieving this goal by minimizing downtime through the integrated planning and scheduling of repairs indicated by condition monitoring techniques. Thermal runaways induced by conduction problems deteriorate insulating material and cause disruptive dielectric discharges resulting in arcing faults. Therefore, having the ability to directly measure the temperature of the contacts while in service will provide more information to determine the true condition of the equipment. It allows connective measures to be taken to prevent upcoming failure. Continuous temperature monitoring and event recording provides information on the energized equipment's response to normal and emergency conditions. On-line temperature monitoring helps to coordinate equipment specifications and ratings, determine the real limits of the monitored equipment and optimize facility operations. Using wireless technique eliminates any need for special cables and wires with lower installation costs if compared to other types of online condition monitoring equipment. In addition, wireless temperature monitoring works well under difficult conditions in strategically important locations. Wireless technology for on -line condition monitoring of energized equipment is applicable both as stand alone system and with an interface for power quality monitoring system. The paper presents the results of wireless temperature monitoring: of electrical equipment at a power plant.

• IE interfaces
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• v.10 no.3
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• pp.75-93
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• 1997

Unlike individual applications, it is extremely hard to obtain user requirements for group systems, since there exists very complicated dynamics in group. This may result in spreading a great amount of products with a broad range of contents. Thus, this study presents a comparative analysis of groupware products. As a result, these products have been categorized into three areas which include cooperation/document management systems, collaborative writing systems, and decision-making/meeting systems. While the systems reviewed here focus on the cooperation/document management systems, the other two areas will be dealt in details in part Ⅱ. The first area ends up with two large categories such as proprietary groupware products and intranet groupware products. However, it has been observed that there is a natural convergence between these two categories. Consequently, the comparative analysis has been performed in terms of functions provided on the two categories and a combined category. Each group of the functions has been divided into three parts which consist of basic functions, quasi-basic functions, and others. Such a decision has been made based on the frequency rate of the functions provided in the products. With a more strict rule, the basic functions comprise electronic mail, sanction, bulletin board, document management, scheduling, security, Web browser, and Internet connectivity. This study also provides a framework for integrated functional model of groupware systems. The basic functions are merged into the model. However, the model is so flexible that it can partially include the quasi-functions in addition to the basic functions. In the future, it is expected that a large number of products will stem from the modification of the functional model.

• Korean Journal of Construction Engineering and Management
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• v.5 no.2 s.18
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• pp.123-135
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• 2004

Construction accident have been increasing in despite of safety management activities and education in construction site. This study surveyed safety organization, education, safety management, scheduling, safety checklist with construction firms in order to grasp the actual condition. A improved method is suggested that safety checklist is supplemented with various safety materials and then stored as database. Furthermore, safety checklists are connected and operated with schedule in ender to more efficiently prevent construction accidents.

• The Transactions of the Korea Information Processing Society
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• v.4 no.7
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• pp.1781-1787
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• 1997

Future high speed networks are expected to use the Asynchronous Transfer Mode(ATM), which provides desired quality of service for the various traffic types(e.g., voice, video and data). Proper traffic control scheme helps ensure efficient and fair operation of networks. In this paper, we analyze various related traffic-control strategies and propose a new traffic control scheme and ATM control architecture with an integrated buffer management method and multi-thresholds in order to solve the problem of each class's cell loss ratio and cell delay in ATM networks. In addition, we evaluate the performance improvement of the proposed traffic control scheme through simulation. As shown in the result, the proposed traffic control scheme improves cell loss ratio in proportion to the buffer size.

• Journal of the Korean Institute of Navigation
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• v.8 no.1
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• pp.1-16
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• 1984

The economical property of a shipping enterprise, as well as other transportation industries, is determined by the difference between the freight earned and expense paid. This study can be regarded as a division of optimizing ship allocation to routes under the integrated port transport system. Fleet planning and scheduling require complicated allocations of cargoes to ships and ships to routes in order to optimize the given criterion function for a given forecast period. This paper deals with the optimum ship allocation problem minimizing the operating cost of ships in a shipping company. Optimum fleet operating for a shipping enterprise is very important, since the marine transportation is a form of large quantity transport requiring long-term period, and there is a strong possibility to bring about large amount of loss in operation resulting from a faulty ship allocation. Where there are more than one loading and discharging ports, and a variety of ship's ability in speed, capacity, operating cost etc., and when the amount of commodities to be transported between the ports has been determined, then the ship's schedule minimizing the operating cost while satisfying the transport demand within the predetermined period will be made up. First of all a formula of ship allocation problems will be established and then will be constructed to solve an example by the Integer Programming application after consideration of the ship's ability, supply and demand of commodity, amount of commodity to be transported, operating costs of each ship etc. This study will give good information on deciding intention for a ship oprator or owner to meet the computerization current with shiping management.