• Transactions of Materials Processing
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• v.12 no.6
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• pp.521-528
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• 2003

Powder injection molding (PIM) uses the shaping advantage of injection molding but is applicable to metals and ceramics. This process combines a small quantity of polymer with an inorganic powder to form a feedstock that can be molded. After shaping, the polymeric binder is extracted and the powder is sintered, often to near-theoretical densities. According1y, PIM delivers structural materials in a shaping technology previously restricted to polymers. The process overcomes the shape limitations of traditional powder compaction, the costs of machining, the productivity limits of isostatic pressing and slip casting, and the defect and tolerance limitations of conventional casting. Since 1980s when major attention was given to PIM process, it has been widening the application area from small parts with complex shape and tailored properties to structural parts requiring strength and ductility as in automotive, military and medical industries.

• Journal of Powder Materials
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• v.9 no.4
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• pp.211-217
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• 2002

It is well known that the powder injection molding(PIM) process can overcome the shape limitations of traditional powder compaction, the costs of machining, the productivity limits of isostatic pressing and slip casting, and the defect and tolerance limitations of conventional casting. Increasing demands from industry for not only the dimensional accuracy nut mechanical strength in PIMed parts have had much effort focused on the investigation of mechanical properties of mechanical strength in PIMed parts have had much effort focused on the investigation of mechanical properties of sintered parts formed with high-strength metallic powders. The 17_4 PH $10\mu{m}$ were injection-molded into flat tensile specimens. Sintering of the compacts was carried out at the various temperatures ranging from 900 to $1350^{\circ}C$. Sintering behavior of the compacts and tensile properties of sintered specimens were investigated.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.50
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• pp.45-54
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• 1999

Cellular manufacturing(CM) is a manufacturing philosophy and strategy for improving both productivity and flexibility. Cell formation(CF), the first and key problem faced in designing an effective CM system, is a process whereby parts with similar design features or processing requirements are grouped into part families, and the corresponding machines into machine cells. In this paper, a sophisticated fuzzy mixed-integer programming model is proposed to simultaneously form manufacturing cells and minimize the total costs of dealing with exceptional elements. Also, we will proposed a new method to solve the cell formation problem in the fuzzy environment.

• ETRI Journal
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• v.28 no.5
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• pp.692-695
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• 2006

Recently, there has been a constant barrage of worms over the Internet. Besides threatening network security, these worms create an enormous economic burden in terms of loss of productivity not only for the victim hosts, but also for other hosts, as these worms create unnecessary network traffic. Further, measures taken to filter these worms at the router level incur additional network delays because of the extra burden placed on the routers. To develop appropriate tools for thwarting the quick spread of worms, researchers are trying to understand the behavior of worm propagation with the aid of epidemiological models. In this study, we present an optimization model that takes into account infection and treatment costs. Using this model we can determine the level of treatment to be applied for a given rate of infection spread.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.1
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• pp.33-40
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• 2014

Air compressor is an important facility with electric power in the industry. However, because of the noise and vibration of air compressor and is installed outside the building management difficulty. In this study, MCP (Micro Control Processor) to remote monitoring of the air compressor via the compressed air through improved quality and allows stable maintenance were designed. So, increase the productivity improvement of energy-saving effect can be obtained. Remote real-time information stored on your PC to manage air compressor equipment was higher reliability. Monitoring system is developed in this study was applied to embedded systems. It is easy to install air compressor, and low maintenance costs was to raise the economic impact.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.12-13
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• 2013

Free-form building is increasing because of request that an order to raise the value and request of the local residents and the government trying to own iconic and beautiful buildings. In addition, the installation and production of free-form concrete segment are now available because of development of construction technology, such as the development of materials and equipment. However, the production of free-form concrete segment requires a lot of time and manpower than shaping. In particular, resources of the mold for the production of free-from segment will be invested excessively because mold can not be recycled. Thus, the problems of increased costs, construction periods and loss of productivity occur. To solve these problems, this study proposes a technique of making the mold of for variable within a short time. Technique proposed in this study can be recycled die and will realize fast and accurate free-form concrete segment.

• Korean Institute of Interior Design Journal
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• no.29
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• pp.163-172
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• 2001

An office is understood as a system consisted of three subsystem : office work, technology and organization. In the age of information, an office is a complicated device in an organization to create, process, modify and deliver various information for organizational goals. The purpose of this study is to provide design guidelines on office workstations based on the analysis of employees' preference and work-style responding to current changes of an organization and work process. Through a literature survey, the study briefly reviewed characteristics of interior design to find changing factors and directions of office interior. Work characteristics in an office are analyzed based on information, activity and communication characteristics while office environment is analyzed based on physical and technological factors. Finally, questionnaire items are derived from a critical comparison between work characteristics and workstation organization(furniture etc) factor. workplace strategies by preference are suggested to increase office productivity, employee satisfaction and to reduce space costs.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.4
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• pp.559-569
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• 1998

Cellular manufacturing system (CMS) has been recognized as an alternative to improve manufacturing productivity in conventional batch-type manufacturing systems through reducing set-up times, work-in-process inventories and throughput times by means of group technology. Most of the studies on the design of CMS assumed that each part has a unique process plan, and that its demand is known as a deterministic value despite of the probabilistic nature of the real world problems. This study suggests an approach for designing CMS, considering both alternative process plans and uncertain demand. A mathematical model is presented to show how to minimize the expected amortized and operating costs satisfying these two relaxations. Four heuristic algorithms are developed based on tabu search which is well suited for getting an optimal or near-optimal solution. Example problems are carried out to illustrate the heuristic algorithms and each of them is compared with the deterministic counterpart.

• Journal of Microbiology and Biotechnology
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• v.18 no.5
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• pp.885-888
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• 2008

In this work, we demonstrate that glycolytic intermediates can serve as efficient energy sources to regenerate ATP during continuous-exchange cell-free (CECF) protein synthesis reactions. Through the use of an optimal energy source, approximately 10 mg/ml of protein was generated from a CECF protein synthesis reaction at greatly reduced reagent costs. Compared with the conventional reactions utilizing phosphoenol pyruvate as an energy source, the described method yields 10-fold higher productivity per unit reagent cost, making the techniques of CECF protein synthesis a more realistic alternative for rapid protein production.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.33
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• pp.45-53
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• 1995

The Purpose of this paper is to describe and demonstrate a quantitative procedure for evaluating alternative material handling systems that are being considered for possible purchase. The procedure considers both quantitative factors(i.e. costs) and qualitative factors(i.e. equipment productivity) that should be considered in the evaluation process. Since these factors are not always quantifiable it is necessary that the procedure be able to quantify all factors in commensurable units. This is accomplished via a modification of the Brown and Gibson model for facility site location and selection. The model was demonstrated via a case example that encompassed the derivation of performance measures for three material handling systems.