• 산업공학
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• 제21권3호
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• pp.247-253
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• 2008

There are various types of unexpected troubles in service of a thermal power plant, which consists of many complicated high-tech mass equipments. The troubles are mostly caused by the manufacturing defects, the material deteriorations, the human errors, and others. Failures of its system due to the troubles, can bring on the extravagant economic loss and the qualitative degradation of electricity. Especially, it is most important to find a way to decrease human errors because it can result in not only the economic loss, but also morale declination of employees or the department related to the trouble. Therefore, we categorize previous troubles related to the human errors, and try to show the causations and the counter-measures based on the various categories such as maintenance, an operation, and system of the thermal power plants.

• 소성∙가공
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• 제21권8호
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• pp.473-478
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• 2012

The yoke, a component of conventional motor-driven power steering system, often contains welding defects from its manufacturing process. To eliminate these defects, the precision cold forging process has been tried. In this study, the double-action complex forging has been used to manufacture a torsion joint yoke. The backward extrusion proved faster than the forward extrusion in forging of the product. The double-action complex forging process utilized an upper die composed of a punch, a punch guide, a disc spring and a coil spring. The forged material pushes up the punch guide, and then the disc spring and the coil spring balances the backward extrusion force. Consequently, the flow of material was essentially in the forward direction, resulting in a successful forging operation. The forging load of Al 6061-T6 was higher than that of the automotive structural hot rolled plate.

• 지역연구
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• 제10권1호
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• pp.19-37
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• 1994

The past studies on the change of industrial location can be reinterpreted as spatial determinism, decision making process determinism and industrial sturcure determinism according to the view of the mutual operation between the economic activity and spatial structure. From the point of the industrial structure determinism which focuses on the fact that the locational type of production activity can be differenciated by the structural change of industry itself, it is proper to explain the change of industrial location not only by spatial condition but also by containing the fundamental changing causes for the reorganization of the spatial condition. One of the most important changing causes for reorganizing economic space is industrial technology. This study aims to explain the spatialization process of industrial technology and consists of the process of suggesting the hypothesis that the spatialization process is differentiated according to the production organization as the user of industrial technology and the user of industrial technology and the production system as using method. In other words, this study attempts to internalize the technology variable, which has been treated as external in the past studies on the industrial location, as an independent one and consider the production organization and production system as a paramenter, so that it can represent 'conceptual framework' for explaining the change of industrial location.

• 한국자동차공학회논문집
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• 제21권5호
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• pp.40-46
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• 2013

Automatic swing door for an automotive application is considered. The equation of motion for a driver side swing door is introduced and gravity cancellation control scheme is adapted. The control scheme supposed to cancel the moment due to the tilt of the car. A speed control is suggested for door operation automation but the output of the speed control is not suppose to be precise as for the manufacturing system control. In the frame of the velocity control of the door, feedback linearization was applied for collision detection. The collision detection performance is satisfactory. The estimate of the magnitude of disturbance due to the collision is close to the actual magnitude of disturbance. Simulation study has been performed to gain insight into the system behavior. Also real test on the prototype hardware has been performed for verification purpose.

• 대한조선학회논문집
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• 제53권5호
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• pp.428-434
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• 2016

A lot of drawings for pipe construction and installation are needed to construct plant process system on the offshore plant structures. Depending on their scale or complexity, the required number of drawings related pipes sometimes amounts to several hundreds of thousands. Most major shipyards, therefore, have their own system which can automatically depict pipes’ geometric, manufacturing, and BOM(Bill of Material) information on the drawings. However, as the complexity and absolute quantity in the isometric region on the drawings is increased, the information extraction from the customized DB and positioning at the typical locations does not get to be enough to avoid the overlap between geometric contours, labels, and symbols. For this reason, the novel methods to arrange additional annotations without overlaps are presented in the paper. This approach is expected to increase the readability and legibility of the drawing and prevent the human error, and finally decrease the time-consuming and tedious jobs which are unnecessarily required to designers.

• 제어로봇시스템학회논문지
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• 제9권1호
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• pp.90-98
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• 2003

The real-time industrial network, often referred to as fieldbus, is an important element for building automated manufacturing systems. Thus, in order to satisfy the real-time requirements of field devices, numerous fieldbus protocols have been announced. But the application of fieldbus has been limited due to the high cost of hardware and the difficulty in interfacing with multi-vendor products. Therefore, as an alternative to fieldbus, the computer network technology, especially Ethernet (IEEE 802.3), is being adapted to the industrial environment. However, the crucial technical obstacle for Ethernet is its non-deterministic behavior that makes it inadequate for industrial applications where real-time data have to be delivered within a certain time limit. Recently, the development of switched Ethernet shows a very promising prospect for industrial application due to the elimination of uncertainties in the network operation resulting in much improved performance. This paper focuses on the application of the switched Ethernet for industrial communications. More specifically, this paper presents an analytical and experimental performance evaluation of the switched Ethernet and a case study about networked control system.

• 제어로봇시스템학회논문지
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• 제14권2호
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• pp.184-190
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• 2008

This paper describes a message model based on XML (eXtensible Markup Language) to present real-time data from sensors and instruments at manufacturing processes for web service. HTML (Hyper Text Markup Language) is inadequate for describing real-time data from process control plants while it is suitable for displaying non-real-time multimedia data on web. For XML-based web service of process data, XML format for the data presentation was proposed after investigating data of various instruments at steel-making plants. Considering transmission delay inevitably caused from increased message length and processing delay from transformation of raw data into defined format, which was critical for operation of a real-time system, its performance was evaluated by simulation. In the simulation, we assumed two implementation models for conducting the transformation function. In one model, transformation was done at an SCC (Supervisory Control Computer) after receiving real-time data from instruments. In the other model, transformation had been carried out at instruments before the data were transmitted to the SCC. Various tests had been conducted under different conditions of offered loads and data lengths and their results were described.

• 한국공작기계학회논문집
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• 제14권4호
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• pp.104-109
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• 2005

The catalyst layer design is one of the most important factors to enhance the performance of PEMFC(Proton Exchange Membrane Fuel Cell) system. The hydrophobic and ion conductive type is studied for the MEA(Membrane Electrolyte Assembly). It is found that those have some limitations for performance enhancement when they are used separately. Thus, the dual catalyst type, a mixed model, is developed for the better MEA performance. In the meantime, the design of flow field plate is subsequently carried out in order to give more enhanced output during its operation. The conductivity of flow field plate showed better performance in the case of manufactured by the more compressed process(20MPa) than by the less compressed process(10MPa). The micro-structure of the flow field plate is examined in details using SEM(Scanning Electron Microscope) to analyse the effects on the different compression processes.

• 디지털융복합연구
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• 제10권7호
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• pp.99-106
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• 2012

본 본 연구는 중규모 기업의 AIS시스템 아웃소싱이 업무성과와 시스템성과에 나타나는 영향관계를 탐색하고자 하였다. 또한 AIS의 아웃소싱 결과를 통해 효율적인 운영방안을 모색하고자 하였다. 본 연구에서는 중규모의 정보화 기업을 중심으로 실무부서와 관리부서 그리고 시스템운영부서를 중심으로 AIS의 현황을 분석하여 실증분석을 실시하였다. 본 연구결과를 요약하면 첫째로, 중규모의 기업에서 AIS 아웃소싱은 초기 회계모듈만 도입 운영하는 경우 업무성과가 높은 것으로 분석되었다. 둘째, AIS의 아웃소싱에서 통합모듈을 통해 운영하는 경우 시스템에 대한 성과는 매우 높은 것으로 나타났다. 통합운용에 따른 상승효과로 분석된다. 본 연구의 결과는 향후 중소규모 제조업의 AIS아웃소싱 방법 및 구축 방향을 제시해 줄 것으로 기대된다.

• 산업경영시스템학회지
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• 제32권4호
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• pp.1-8
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• 2009

The studies on semiconductor industrial accident in korea have been focused on the frequencies of each type of safety management employee, characteristics, cause and unsafe conditions, acts and so on. Those attributes of semiconductor industrial accidents were usually analyzed independently, so that it was hard to provides a wel-developed process and systematic guidelines for efficient safety management. Therefore, there were a few studies based on comprehensive survey in terms of the shape type of safe management. The questionnaire survey carried out for the 284 workers who were responsible for safety management in center with cooperation companies in semiconductor industry factor analysis showed that there were three factors of safety management. First, investment and operation and management for accident prevention, Second, unsafe act and condition, safety management Third, general human error and behavior. The industries of respondents were correlative with three groups. Three groups showed statistically significant differences on the number of cases. Actually, the group with the larger investment and the more unsafe cause, human error of accidents prevention had a smaller causes of accident cases.