• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.436-437
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• 2008

초기투자비용의 과다 발생으로 제한적으로 시공되고 있는 지중송전케이블의 역사는 1971년 154kV급 OF케이블이 처음으로 한국전력에 의해 상용운전후 현재에 이르고 있으며, 최근들어 지중케이블에서 발생된 송전선로 고장은 대부분 대형화되고 있어 초창기 시공된 케이블 종류의 대부분을 차지하고 있는 OF 케이블의 현상태를 정확하게 진단하고 각종 현상들을 분석하여 결론을 도출하지 않으면 안된다. 실제 계통에서 운전되고 있는 설비를 철거하여 상태를 판정할 수 있는 여건이 아니기 때문에 케이블의 현상태를 정확하게 분석하기 위해서는 절연유의 분석 등 간접적인 방법을 택하지 않을 수 없다. OF 케이블에 있어서 급유조는 케이블의 성능에 가장 직접적인 영향을 미치는 구성요소이며, 급유조에서 기준치보다 $2{\sim}5$배에 해당되는 이상가스의 발생원인을 파악하여 예방대책을 수립할 수 있게 되었다. 분리기의 용접부분 또는 접합부분에 틈이 생기지 않도록 하고 틈 부위에는 세라믹이나 폴리머등으로 코팅하여 $H_2$가스의 과다 발생을 방지할 수 있었다.

• Proceedings of the KIEE Conference
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• 1999.07b
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• pp.894-896
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• 1999

PID 제어는 50년의 역사를 갖기 때문에 현장의 사용자는 이 제어방식에 익숙해져 있으며, 제어장치의 구성이 간단하며 제어기의 최적동조가 가능하므로 많은 분야에서 사용되고 있다[1]. 그러나 PID 제어기에 의해서 얻은 결과에 대하여 만족하기 위해서는 많은 시행착오를 겪어야 한다. 또한 만족하는 결과를 얻었다고 할지라도 외란, 플랜트의 동특성이 바뀌는 경우 시스템을 추종하지 못하기 때문에 파라미터를 재조정하여야 한다. 유전 알고리즘은 자연세계의 진화 현상에 기초한 계산모델로서 John Holland에 의해서 1975년에 개발된 전역적인 최적화 알고리즘이며[1][2], 비선형 고차원, 불연속, 다중모드, 노이즈 함수 등에 대하여 강건함을 보여주고, 복잡한 탐색 공간에서 최적 값을 스스로 발견하는 학습 능력을 갖는다. 이 방법은 재생산, 교배, 돌연변이를 통하여 최적해를 찾은 방법으로 1989년에 D. E. Goldgerg에 의해서 체계적으로 정리된 후 여러 분야에서 응용되고 있다[3][4]. 그러나 유전 알고리즘은 목적함수만을 이용하여 해집단을 탐색하기 때문에 숙련운전자가 원하는 제어 특성 명세인 상승시간, 정착시간, 초과량(oveshoot) 둥을 구체적으로 명시하여 제어에 반영할 수 없다. 또한, 유전 알고리즘은 입력 값이 크게 바뀔 경우 다른 시스템으로 인식하여 새로운 탐색을 수행하는 단점을 가지고 있다. 본 논문은 첫째, 기준모델을 도입하여 플랜트의 성능을 기준모델로 표현하여 플랜트가 요구하는 성능지표를 정량적으로 규정하는 것이 가능하였다. 또한, 이것은 미지 플랜트 동특성을 식별하기 위한 신호로 사용되어, 플랜트의 정보를 얻는데 이용되었다. 즉, 기준모델과 플랜트 출력사이의 추종 오차 정보가 적응기구인 PID 유전제어기의 입력으로 사용되며, 구형파 입력의 경우에도 기준모델과 플랜트의 출력차는 크게 변하지 않는다. 따라서, 유전 알고리즘의 목적함수에 기준 모델을 제안 적용하여 안정적이고, 세밀한 제어를 수행하였다. 둘째, PID의 간단하면서 확실한 제어가 가능하다는 점과 전역적인 최적값을 찾을 수 있는 유전 알고리즘을 적용하여 고속제어를 요하는 직류 서보 모터(DC Servo Motor) 운전 시 실시간 파라미터 동조에 적용하였다.

• Geophysics and Geophysical Exploration
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• v.12 no.1
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• pp.56-68
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• 2009

Ongoing and extensive urbanisation, which is frequently accompanied with careless construction works, may threaten important archaeological structures that are still buried in the urban areas. Ground Penetrating Radar (GPR) and Electrical Resistivity Tomography (ERT) methods are most promising alternatives for resolving buried archaeological structures in urban territories. In this work, three case studies are presented, each of which involves an integrated geophysical survey employing the surface three-dimensional (3D) ERT and GPR techniques, in order to archaeologically characterise the investigated areas. The test field sites are located at the historical centres of two of the most populated cities of the island of Crete, in Greece. The ERT and GPR data were collected along a dense network of parallel profiles. The subsurface resistivity structure was reconstructed by processing the apparent resistivity data with a 3D inversion algorithm. The GPR sections were processed with a systematic way, applying specific filters to the data in order to enhance their information content. Finally, horizontal depth slices representing the 3D variation of the physical properties were created. The GPR and ERT images significantly contributed in reconstructing the complex subsurface properties in these urban areas. Strong GPR reflections and highresistivity anomalies were correlated with possible archaeological structures. Subsequent excavations in specific places at both sites verified the geophysical results. The specific case studies demonstrated the applicability of ERT and GPR techniques during the design and construction stages of urban infrastructure works, indicating areas of archaeological significance and guiding archaeological excavations before construction work.

• Archives of design research
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• v.19 no.1 s.63
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• pp.79-88
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• 2006

A human face figure is a visual symbol of identity. Each different face per person is a critical information differentiating each person from others and it directly relates to individual identity. When we look back human history, historical change of recognition for a face led to the change of expression and communication media and it in turn caused many changes in expressing a face. However, there has not been no time period when people pay attention to a face more than this time. Technically, the advent of computer graphics opened new turning point in expressing human face figure. Especially, a visual image which can be produced, saved, and transferred in digital has no limitation in time and space, and its importance in communication is getting higher and higher. Among those visual image information, a face image in digital is getting more applications. Therefore, 3d (3-dimensional) expression of a face using computer graphics can be easily produced without any professional techniques, just like assembling puzzle parts composed of the shape of each part ands texture map, etc. This study presents a method with which a general visual designer can effectively express 3d type face by studying each producing step of 3d face expression and by visualizing case study based on the above-mentioned study result.

• 한국지구물리탐사학회:학술대회논문집
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• 2002.09a
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• pp.139-162
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• 2002

Since weak zones or geological lineaments are likely to be eroded, weak zones may develop beneath rivers, and a careful evaluation of ground condition is important to construct structures passing through a river. Dc resistivity surveys, however, have seldomly applied to the investigation of water-covered area, possibly because of difficulties in data aquisition and interpretation. The data aquisition having high quality may be the most important factor, and is more difficult than that in land survey, due to the water layer overlying the underground structure to be imaged. Through the numerical modeling and the analysis of case histories, we studied the method of resistivity survey at the water-covered area, starting from the characteristics of measured data, via data acquisition method, to the interpretation method. We unfolded our discussion according to the installed locations of electrodes, ie., floating them on the water surface, and installing at the water bottom, since the methods of data acquisition and interpretation vary depending on the electrode location. Through this study, we could confirm that the dc resistivity method can provide the fairly reasonable subsurface images. It was also shown that installing electrodes at the water bottom can give the subsurface image with much higher resolution than floating them on the water surface. Since the data acquired at the water-covered area have much lower sensitivity to the underground structure than those at the land, and can be contaminated by the higher noise, such as streaming potential, it would be very important to select the acquisition method and electrode array being able to provide the higher signal-to-noise ratio data as well as the high resolving power. The method installing electrodes at the water bottom is suitable to the detailed survey because of much higher resolving power, whereas the method floating them, especially streamer dc resistivity survey, is to the reconnaissance survey owing of very high speed of field work.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.5 no.4
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• pp.83-93
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• 1994

1886년 고트리브 다이믈러와 칼 벤즈가 가솔린 자동차를 개발한 이후 100여년이 지난 지금 자동차는 비약적으로 진보, 발전하여 현대 산업사회와 개인의 생활에 있어 산업운송수단과 이동수단으 로서 필요불가결하게 되어 밀접한 관계를 갖고 있다. 우리나라 자동차 공업의 역사는 자동차가 사회적, 경제적 효용에 따라 그 생산과 보유대수가 날이 갈수록 증가 일로에 있으며, 자동차의 생산대수는 전세 계에서 년간 약 50,606천대('94년)로서 중요한 국가 기간 산업으로 자리하고 있다. 한편 전기, 전자공업의 발전에 따른 자동차의 Car Electronics가 많이 채용되게 됨에 따라 현재의 자 동차에는 대부분이 전자제어 System으로 구성되어 있다. 최근에는 Micro Processor를 이용한 전자부품이 많이 사용되어 전자파에 대한 문제가 다양하게 발생 하고 있다. 예를 들면 미국 캘리포니아주에서 전자점화제어장치와 연료분사 장치를 설치한 구미의 자동 차가 주행중 28MHz, 28W의 아마추어 무선을 탑제한 자동차가 통과할 때 엔진이 고르지 못한 보고가 있 었고, 화학섬유로된 옷을 착용한 전자부품이 다른 부품에 영향을 주는 사례가 맣아지고 있다. 따라서 자동차에는 여러가지의 전장품, 전자기기를 탑재하기 때문에 자동차 자체에서 발생하는 것과 외부로 부터 받는 전자장해 EMI(Electromagnetic Interference), EMS(Electromagnetic Susceptibility) 가 문제로 되어 자동차 및 부품 maker에 의한 EMC(Electromagnetic Compatibility) 평가의 중요성이 고조되고 있다. 차제무전기, 차제무전기, Car-Radio는잡음방해를 많이 받기도 하지만, 잡음원이 되기 도 한다. 또한 Engine 제어, 차속제어, Brake 제어등에 이용되는 전자제품은 방해에 의한 오동작 또는 파괴가 발생하여 주행기능, 안전성에 문제가 야기되지 않도록 해야 한다. 이러한 전자기 환경은 모두 RF(Radio Frequence)와 자동차에서의 전자파 장해 문제의 원이 될 수 있다. 자동차 및 그 부품의 전자기 방해에 관한 규격화는 1987년부터 괄목할 만하게 진행되어 이에 따른 규제 움직임이 IEC(International Electrotechnical Commission: 국제전기기술위원회) 산하의 하부기 구인 CISPR(International Special Committeeon Radio Interference: 국제 무선 장해 특별위원회)가 전자기 방해파에 대한 측정법 통일안을 제안 하였고, ISO(International Standardization Organiza- tion: 국제표준화 기구) 가운데 TC 22/SC3가 자동차의 전장품에 대한 장해를 논의히고 있다. 특히, 자동차의 EMC에 관한 국가 규격은 국제 규격에서 저술한 바와 같이 특별히 규정된 것이 없고 VDE(Verband Deutscher Elektrotechniker: 서독전기기술 협회)와 SAE(Society of Automotive Engi- neers: 자동차 기술자 협회)에서 비교적 활발하고 Jaso(Japanese Automobile Standards Organization: 일본 자동차 표준협회)에서 많이 진행중에 있다. 본 고에서는 자동차의 전자제어에 따른 잡음 발생 요인과 전자파 간섭 관련 자동차 규격과 시험평가 방법에 대해 간단히 소개 하였다.

• The Journal of the Korea Contents Association
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• v.10 no.9
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• pp.496-503
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• 2010

The art education in the latter period of the 20th century was conducted in the same cramming method as education of expressionism and pragmatism from beginning to end, while post-modernism can be interpreted as a viewpoint of reflecting the diversity, popularity and needs of the era. Under such circumstances, this research is aimed at looking for an educational method that can reflect the educational method of this present period. Thus, this research is trying to analyze the works of some artists showing a variety of styles of the post-modernism period and to inquire into a new direction at a viewpoint of the post-modernism where divers cultures co-exist. This research considered these artists' works as the objects for comparison because there exists an aspect of something in common in that there are more diverse-style-based expression in the post-modernism art education though their subject and format are different individually. Therefore, this research is conducted at a viewpoint of assisting in the understanding of more diverse style-based painting in the post-modernism education.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.6
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• pp.22-30
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• 2004

It is an attempt to suggest the standard valuation method of the environmental illumination for the bridges across the Han-river from an aesthetic point of view, deviating from the technical and traditional viewpoint. In Korea the current evaluation criterion to verify the value of bridge design has a partiality for the technical and structural safety rather than the sentient beauty on the whole. However, the recently cultural reform of Korean mass society with the elevation of the standard of living forces the engineering designers for bridges to focus not only on competing physical structures but also on enhancing the formative beauty including the illumination effects for night view. Additionally, the new policy, which transforms the environments around the Han-river into the major tourist attractions has been executing strongly by the city authorities to revitalize the symbolic, historic, and cultural identity of the capital city with the introduction of the high-quality environmental illumination for the bridges. As a result, It becomes necessary to establish the manual and standardization of the environmental illumination planning for the city in terms of the formative beauty, and this study is to suggest the valuation model method of the environmental illumination for the bridges as the initial step of the standardization. In the study, the valuation items of the standard questionnaire are selected by the documentary records and the consultation of various experts in architecture, design, fine art, urban planning and even administration to verify the essential elements of the aesthetic beauty with the local amenity and the environmental harmony for the chosen bridges across the Han-river.

• Journal of Korea Game Society
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• v.12 no.1
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• pp.103-111
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• 2012

Games in 1970s have used the savings of analog wavelength as in music and the like on hardwares of small cassette, gramophone, and the like. Due to these configuration elements, durability has to be declined so much. In the event of using the music on the video game, more affordable method is to use the computer chip to convert the analog sound into the computer code to convert into the electric wavelength to send to the speaker. The sound effect of the game is generated in this method. The technical limit has been gradually overcome to grant more freedom to the composers and the sound track pre-recorded on the optic disc and the like has emerged. The game developers of today have made several attempts on the technology to produce the game music. This study has contemplated the process of advancement in the change of game music production with the influence on technology and business.

• Sijohaknonchong
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• v.30
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• pp.109-146
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• 2009

It is academically recognized that Jeong Wan-Young's sijo better represent Oriental ideas. The purpose of this study is to investigate Taoistic characteristics of Jeong Wan-Young's sijo. This is an effort to succeed and further deepen and extend previous relevant researches. For the purpose, this researcher categorized the poet's sijo in accordance with such characteristics as above mentioned. Findings of the study can be summarized as below. Pieces of Jeong Wan-Young's sijo which are based on Taoistic ideas are largely classified into three groups. First, some pieces of Jeong Wan-Young's sijo represents an orientation of return to hometown which is brought by the sense of loss. His sense of loss is attributed to the facts that his home is not what it was any longer and that he can't return to the old home. To overcome the sense, nevertheless, the poet is dreaming of return to home. The home found in Jeong Wan Young's sijo is something fundamental and original that he purposedly provided against the feeling of loss. It complies with the concept of 'Bokgwigigen(復歸基根)‘ a pursuit of Taoism. Second, other pieces of Jeong Wan-Young's sijo are seeking purity to retrieve childish innocence. Their subjects include the season of spring, dreams of childhood and longing for mother all of which represent the poet's strong desire for such retrieval as above mentioned. It may be said that pursued by that pieces are 'Purity, Feebleness and Smoothness' that are sought by Taoism. Third, other pieces of Jeong Wan-Young's sijo are considering human as a part of nature and seeking human life in harmony with nature. In other words, they are seeking union between human and nature which means going beyond discrimination between self and external objects, that is, 'Mulayangmang(物我兩忘)'. This may refer to return to nature which is the ultimate destination of Taoism.