• Journal of the Korean Society of Manufacturing Process Engineers
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• v.6 no.4
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• pp.15-21
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• 2007

The effect of manufacturing parameters on friction characteristics of motorcycle break system was studied using a disk-on-pad type friction tester. Such parameters conditions have an effect on the frictional factor such as number of ventilated disk hole, applied load, sliding speed, and sliding distance. However, it is difficult to know the mutual relation of these factors. In this study, the friction characteristics using design of experiment containing 4 elements were investigated for an optimal condition for the best motorcycle break system employing regression analysis method. From this study, the result was shown that the applied load in frictional factors was the most important, next to sliding speed, number of ventilated disk hole.

• The Journal of Korean Physical Therapy
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• v.21 no.1
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• pp.57-63
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• 2009

Purpose: We determined the recruitment pattern of lumbar elector spinalis, gluteus maxims, inner and outer hamstring muscle during trunk flexion and extension. Methods: Thirty healthy subjects(male; 15, female; 15) without low back pain and other problems in lower extremities participated in this study. To measure the recruitment pattern, the onset times of electromyographic activity of the muscles were recorded during trunk flexion and return(extension) to standing position. Results: The medial and lateral hamstring muscle was activated first, next elector spinalis, the last, gluteus maximus in trunk flexion. In trunk extension to standing position, the order of recruitment was similar to trunk flexion although the frequency is different. There were different between male and female in flexion and extension movement. Conclusion: The recruitment order of lumbar extensor and hip extensors in trunk flexion and extension will provide database in evaluation and intervention of lower back pain and lumbo.pelvic rhythm disorder.

• Korea-Australia Rheology Journal
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• v.18 no.1
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• pp.31-38
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• 2006

A systematic approach is employed to elucidate the interrelationships among macroeconomic entities such as science, engineering, technology, industry and national economy. Specifically, a conceptual, sequential method has been developed to clearly identify the essential ingredients needed for each macroeconomic entity starting from science to transform to the next one, and all the way to the national economy where the production of added-value is of overriding importance. The results thus obtained can then be utilized for macroeconomists to readily apply the engineering theory and knowledge to various macroeconomics situations, while engineers can likewise utilize the results on top of the microeconomic knowledge already prevalent in many engineering fields in getting better grasp of the seemingly difficult nation's macroeconomic picture. Other peripheral concepts and issues such as the evolutionary development of industry, the perspectives of the $21^{st}$ century civilization, an analogy between macroeconomics and chemical engineering, and national policies for each macroeconomic entity are also presented in this study.

• The Journal of Society for e-Business Studies
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• v.5 no.1
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• pp.19-37
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• 2000

There are numerous researches being studied regarding Electronic Commerce (EC), that is one of the hottest issues for the 21 century in the various areas such as management, engineering and science; etc, This paper concerns the logistics functions which are essential for completing a commerce process even under the EC environment. Even though both the traditional and the electronic commerce via internet share many common problems regarding logistics, new logistical issues are generated as the EC is being popularized. We study the logistics competitiveness under the EC environment and provide ways to improve the logistical performance. We first point the emerging logistical paradigm to check the issues under EC. Next, logistics competitiveness factors are provided. Finally we propose several ways for the logistical performance and cost perspective.

• Journal of Industrial Technology
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• v.21 no.A
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• pp.181-188
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• 2001

An XML is an markup language which has been focused on the next generation Web programming language. It easily represents the complex structure of a document, and it is possible to provide the access control over each component of an XML document. An implicit authorization technique means that granting an authorization to a node has effect on granting the same implicit authorization to its all descendants. Therefore, it enhances the time for the authorization grant and reduces the memory required for the authorization information. An authorization technique using an intention type and a authorization replacement solves a redundancy problem and decides whether the access is possible or the authorization conflict occurs at the first attempt.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.269-274
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• 1999

As the semiconductor industry enters the next century, we are facing to the technological changes and challenges. Optical lithography has driven by the miniaturisation of semiconductor devices and has been accompanied by an increase in wafer productivity and performance through the reduction of the IC image geometries. In the last decade, DRAM(Dynamic Random Access Memories) have been quadrupoling in level of integration every two years. Korean chip makers have been produced the memory devices, mainly DRAM, which are the driving force of IC＇s(Integrated Circuits) development and are the technology indicator for advanced manufacturing. Therefore, Korean chip makers have an important position to predict and lead the patterning technology. In this paper, we will be discussed the limitations of the optical lithography, such as KrF and ArF. And, post optical lithography technology, such as E-beam lithography, EUV and E-beam Projection Lithography shall be introduced.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1240-1245
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• 2000

A Spacecraft container must afford the satellite a relatively benign thermal, vibration, and particle environment that is oblivious to the extreme temperatures, sand, dust, vibrations and shocks that can accompany the transportation. This paper discusses the extensive yet simple vibration test and validation of one such spacecraft container used for KOMPSA T-1 spacecraft, which was transported from KARl Taejon, Korea to Vandenberg Air Force Base(VAFB) on September 30 and launched successfully December 21, 1999. The test results are presented and compared with the design requirement. The dynamic characteristics of shipping container, such as natural frequencies, satisfied the design requirement and showed that shipping container was well. designed and manufactured. This kind of know-how will help to develop the next generation of Korean space program, such as KOMPSAT-2 and Korean tele-communication satellite.

• Journal of the Korean Data and Information Science Society
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• v.16 no.4
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• pp.879-888
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• 2005

Fashion is hard to expect owing to the rapid change in accordance with consumer taste and environment, and has a tendency toward variety and individuality. Especially street fashion of 21st century is not being regarded as one of the subcultures but is playing an important role as a fountainhead of fashion trend. Therefore, Searching and analyzing street fashions helps us to understand the popular fashions of the next season and also it is important in understanding the consumer fashion sense and commercial area. So, we need to understand fashion styles quantitatively and qualitatively by providing visual data and dividing images. There are many kinds of data in street fashion information. The purpose of this study is to design and implementation for street fashion information analysis system using data fusion. We can show visual information of customer's viewpoint because the system can analyze the fused data for image data and survey data.

• Journal of the Korean Society of Safety
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• v.21 no.5 s.77
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• pp.77-83
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• 2006

The purpose of this study is to assess the organizational personality types, employee-organization fits and the job satisfaction/involvement in a Korea standard nuclear power plant(NPP), which is a representative safety work place. First we chose 427 procedures that are related to safety out of 777 officially managed procedures referenced by 13.5 of FSAR(final safety analysis report). Next, we finally chose 70 procedures of 8 divisions for 44 employees regarding the duties for NPPs' division, experiences of operations, an operational know-how, and the indication of operational weakness. This study used OPTI(organizational personality type indicators) and the combination of 4 preference types for determining the organizational personality to produce personality types of organizations for NPPs' division. To assess the job satisfaction and involvement, we used a questionnaire and an interview, for 300 employees(83.5%) of the Korea standard NPP.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.10
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• pp.840-847
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• 2007

This Paper focuses on modeling and simulation to analyze the characteristic of hybrid vehicle. The system includes a proton exchange membrane fuel cell(PEMFC), photovoltaic generator(PV), lead-acid battery, motor, vehicle and controller. Main electricity is produced by the PEMFC and battery to meet the requirements of a user load. When vehicle is parked in a sunny place, extra power is generated by the photovotaics and is charged in a battery for next drive. Further we evaluate usefulness of this hybrid vehicle by using ADVISOR - the advanced vehicle simulator written in the Matlab/Simulink environment. According to simulation results, the extra power obtained by photovoltaics which have been explored in nature conditions can help to reduce the electrical load of PEMFC and increase the efficiency (over 21 %).