• Journal of Korean Institute of Industrial Engineers
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• v.28 no.4
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• pp.415-424
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• 2002

Semiconductor manufacturing has been emerged as a highly competitive but profitable business. Accordingly it becomes very important for semiconductor manufacturing companies to meet customer demands at the right time, in order to keep the leading edge in the world market. However, due-date oriented production is very difficult task because of the complex job flows with highly resource conflicts in fabrication shop called FAB. Due to its cyclic manufacturing feature of products, to be completed, a semiconductor product is processed repeatedly as many times as the number of the product manufacturing cycles in FAB, and FAB processes of individual manufacturing cycles are composed with similar but not identical unit processes. In this paper, we propose a production scheduling and control scheme that is designed specifically for semiconductor scheduling environment (FAB). The proposed scheme consists of three modules: simulation module, cycle due-date estimation module, and dispatching module. The fundamental idea of the scheduler is to introduce the due-date for each cycle of job, with which the complex job flows in FAB can be controlled through a simple scheduling rule such as the minimum slack rule, such that the customer due-dates are maximally satisfied. Through detailed simulation, the performance of a cycle due-date based scheduler has been verified.

• IE interfaces
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• v.22 no.4
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• pp.347-358
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• 2009

Panning tasks caused by both a small screen and the lower resolution of handheld devices are known to decrease the usability of a mobile internet service. To solve this problem, we proposed FTND, an improved version of Tap-N-Drag widely used in various mobile web browsers. 30 participants performed the panning tasks with FTND embedded in combinations of 2 panning directions of Push Background user interface and Push Viewpoint user interface and 5 panning ratios of 100% (a panning ratio of Tap- N-Drag), 300%, 500%, 700%, and 900%. The usability of FTND was assessed by an objective performance and a subjective preference. The objective performance was measured by a task completion time, the number of clicks, and the number of pixels. The subjective preference was measured by satisfaction, accuracy and ease of use. Push Viewpoint user interface at the panning ratios of 300%, 500%, and 700% proved to be the most efficient way for panning tasks with small handheld devices when performing the task by using the right hand thumb.

• Journal of Korean Institute of Industrial Engineers
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• v.36 no.3
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• pp.176-185
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• 2010

As long as the information systems are spread out, various efforts are being attempted to get the effective results by the system. As a result, a new management strategy has been appeared, referred to as "collaboration", and it is necessary to use a right methodology for modeling collaborative processes accordingly. Even though many modeling methodologies such as IDEF3, Petri-Nets, UML, and ARIS have been widely used for modeling processes, they are inadequate for clearly representing collaborative processes. Some researchers, therefore, have suggested new modeling methodologies for describing collaborative processes including CPM (collaborative process modeling). In this paper, we introduce an extended version of CPM method (i.e., exCPM) as a tool for modeling collaborative works after analyzing advantages and disadvantages of aforementioned methodologies. One of distinct characteristics of exCPM is that model verification is possible by transforming the exCPM models into Petri-Nets models. We also demonstrate transformation of an exCPM model in this paper with case studies for model verification.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.36 no.3
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• pp.133-141
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• 2013

The revitalization of e-business via Internet brings big changes to the postal business, and leads to a tremendous increase of heavy and large sized postal mails with continuing growth of home delivery business. Thus, even though the number of intermediate storages for mail delivery that mailmen use for picking up mails in the middle of mail delivery has been being increased, it has still many problems such as insufficient number and size of the storages as well as avoidance of mail keeping of trust agents. It is necessary that safety of mail keeping, seamless mail delivery, and individual parcel pick-up process reestablishment should be made through an improved counter plan for the problems described previously. This study presents the efficient and right operational plan for the intermediate storage for mail delivery with providing the number and size of intermediate storages per mail delivery sequence according to four different types of post offices.

• Journal of Korean Institute of Industrial Engineers
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• v.16 no.1
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• pp.67-81
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• 1990

Effectiveness of physical exercise in reducing work-related musculoskeletal stress was investigated. This was compared to the stress alleviation accomplished by using ergonomically designed work station. Tasks chosen for the study were data entry and file maintenance on the video display terminal (VDT). Three different measures, namely root-mean-square (RMS) values of electromyogram (EMG), subjective rating and task performance were used for the evaluation. Electromyograms were recorded from the neck, the left and right trapezius muscles in the shoulder region, and L2/L3 region of the back. Subjects rated discomfort levels for the same parts of their body. Task performance was measured by recording typing speed and errors. Each of the five subjects was tested for two days (8 hours/day) in two different work stations. These were the ergonomically designed adjustable work station and the fixed work station of traditional design with no adjustable features. Assigned physical exercises were performed for four minutes, every two hours during the breaks, by the subjects while working in the fixed work station. It was concluded that the physical exercise could be helpful in reducing musculoskeletal stress as effectively as the ergonomic design of the VDT work station.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2367-2371
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• 2003

A new instrument for early detection of Alzheimer's disease is constructed from the investigative items with both the investigation of living environment, and the functional tests of the sense, the physiology, and the left and right brains. This paper describes the indexes obtained from the results of test using a new instrument for early detection of Alzheimer's disease. The indexes for early detection of Alzheimer's disease were obtained from the investigations of the living environment and the social adaptability, the functional tests of the sight and the hearing in the five senses, and the functional tests of left hemispheres in brain.

• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.636-639
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• 2009

In spite of the presence of various kind of Integrated Circuits it's not always easy to get the right part. Besides, it is hard to find a vendor for a small quantity consumers like who develop prototype applications. In this study, we've tried to get the logical signals from the PC based device we've developed that correspondents with the real ICs. It can emulate decoder ICs, multiplexers, demultiplexers and basic logic gates.

• Journal of the Korean Professional Engineers Association
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• v.32 no.6
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• pp.28-34
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• 1999

The trouble of business management of the manufacturing industrial companies in korea are constituted by that average 26∼29% of production management in the worst trouble of business management from 1973 to 1997. A movement for higher productivity and quality is very important of the basis for industry society prosperity. Continuous productivity improvement have a right understanding of a conception of productivity and its effect that are removed an act before the trouble of higher productivity enforcement. The higher productivity is used by way of a welfare society.

• Proceedings of the IEEK Conference
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• 2002.06e
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• pp.303-306
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• 2002

The EMI filter used in switching apparatus is designed on the basis of personal designer experience. A try and error approach leads to a considerables waste of time without assurance to come out to a good solution. The difficulty in the right choice of the component values resides on the dominant role played by their parasitic components at high frequencies and is aggravated by the poor knowledge of the internal impedance of the noise generators. In this paper, we proposed the design technique for the EMI filter effectively using the LISN and the EMI analyzer in the industrial field.

• Proceedings of the KAIS Fall Conference
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• 2003.06a
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• pp.208-210
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• 2003

In spite of the presence of various kind of Integrated Circuits it's not always easy to get the right part. Besides, it is hard to find a vendor fer a small quantity consumers like who develop prototype applications. In this study, we've tried to get the logical signals from the PC based device we've developed that correspondents with the real ICs. It can emulate decoder ICs, multiplexers, demultiplexers and basic logic gates.