• 제목/요약/키워드: duality principle

검색결과 16건 처리시간 0.024초

Three-Phase Soft Switching Sinewave Inverter with Bridge Power Module Package Configurated Auxiliary Resonant AC Link Snubber

  • Iyomori Hisashi;Nagai Shin-ichiro;Shiraishi Kazuhiro;Ahmed Tarek;Eiji Hiraki;Mutsuo Nakaoka
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2003년도 춘계전력전자학술대회 논문집(2)
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    • pp.507-510
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    • 2003
  • This paper presents a novel prototype of tile three-phase bridge power block module type a auxiliary resonant AC link snubber circuit, which is effectively used for the three-phase voltage source type sinewave soft switching PWM inverter using IGBTs. Its operating principle Is described for current source load model, along with its practical design approach based on the simulation data. The performance evaluation of the three-phase voltage source type snewave soft switching PWM inverter incorporating a single three-phase bridge mo여le of active auxiliary resonant AC link snubber treated here Is illustrated, which is concerned with power duality efficiency power loss analysis. This inverter is discussed as compared with those of tile three-phase voltage source type sinewave hard switching PWM inverter. The power loss analysis of this soft switching PWM Inverter using IGBT power modules is evaluated on the basis of the measured v-i characteristics and switching power losses of IGBT, and antiparaliel diodes. The practical effectiveness of this inverter is proven by the power loss analysis for distributed power supply.

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에셔(M. C. Escher) 작품의 프랙탈 속성에 관한 연구 (A Study on the Attributes of Fractal on M.C. Escher′s Works)

  • 류시천;윤찬종
    • 디자인학연구
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    • 제15권1호
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    • pp.5-14
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    • 2002
  • Fractal which was named by Mandelbrot in 1975 and its theory have been taken notice of many fields of scholarship, namely mathematics, physics, geography, architecture, art, philosophy and so on. If we approach Fractal on the basis of the designing cogitation, it can be used not only as one of materials to take a crease thinking in design, also as a due of the methods to assess the design problem with a new point of view. Based on above background, in this study, it was studied on the graphic artist, Morits Collelius Escher who has been well known as the great artist of illusion," and on the attributes of Fractal which were contained in his various work\ulcorner As a reset, the four attributes, namey ′fractal dimension′, ′self-similarity, ′recursiveness′and ′infinity were founded in his works. Also, it was founded that Escher had employed the attributes of Fractal in his almost works for "the representation of the condition of unified-duality," that is to say, for the union of two different dimensions. After this, it is expected that this study shoed be extended to the development of the principle of Fractal-Design on the basis of ′Fractal which can be defined as the phenomenon of repetitious pattern between chaos and order and′the formative beauty of Fractal′.

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한국 대학 실내디자인 관련 교육 현황 분석과 개선 방향 연구 (An Analysis and Directional Study on Current Interior Design Related Education in Korea)

  • 서수경
    • 한국실내디자인학회논문집
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    • 제19권6호
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    • pp.121-128
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    • 2010
  • Interior design education has been developed rapidly since the discipline established in Korea in 1980s but unfortunately the development was without any progressive transition until 1990's. When Korean Institute of Interior Design/KIID inaugurated in 1992, interior design education and related research activities began to be intensified. Despite its effort, there were still confusion about the discipline as there were many similar discipline tracks (architecture, design, fine art, & home economic, etc.) each having an own definition of interior design and introducing different aspects of educating the subject. Education program for interior design still not sufficiently supporting the needs of today's rapidly changing industry nor to prepare the diverse needs of the client. In order for interior design major to be effective in the future and fulfill the needs of current industry development within our society, re-evaluation of our current interior design educational programs in Korea is important. This study will be the beginning of a research series. As the first part of the research series, this particular study has been focused on reviewing of current status of interior design majors in the nation and its current condition. While making suggestion for the changes in curriculum, the following points will have to be considered as basic principle. First, understanding the duality of technology and design to accommodate the contents of design discipline. Second, understanding the need of practice and theory combined for practical education. And lastly, considering ways to adopt the human experience in order to develop creativity in oneself. The focus of this research is only on the interior design discipline, and research method as the following; first, analyze current status by reviewing admission data for 2010. Second, process a survey regarding the interior design education and practice-related issues in admissions and collect opinions from educators and professional designers in the field. Thirdly, with reference to previous studies, suggestions will be made for the discipline to be effective in the field. As mentioned earlier, this study series will continue and develop to suggest improvement in interior design program as well as to provide curriculums for students get ready for the industry with more up-to-date knowledges and creativities.

ROI를 이용한 웨이브렛 기반 디지털 영상의 워터마킹 기법 (A Wavelet-Based Watermarking Scheme of Digital Image Using ROI Method)

  • 김태중;홍충선;성지현;황재호;이대영
    • 정보처리학회논문지B
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    • 제11B권3호
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    • pp.289-296
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    • 2004
  • 일반적인 워터마킹 기술들은 영상의 특성을 고려하지 않은 채 신체 책인 영상에 워터마크를 삽입하는 경우가 많다 본 논문에서는 워터마킹 알고리즘을 웨이브렛을 기반으로 구현을 하였으며, 견고한 워터마크 삽입을 위해 Multi-Threshold Watermark Coding(MTWC)의 원리에 기초하여 Region of Interest(ROI)라고 불리우는 영상의 영역에 큰 계수를 찾아 워터마크를 삽입하게 된다. 이때 Human Visual System(HVS)을 이용하여 견고성과 비가시성의 향상을 도모하였다. 워터마크 삽입대역은 중주파 대역에 삽입을 하게 되는데 중주파 대역에 삽입한 워터마크는 어떠한 영상 처리과정 후에도 높은 비율의 추출을 보였으며, 워터마크가 삽입된 영상의 왜곡정도도 다른 대역보다 상대적으로 적게 나타나므로 중주파 대역에 워터마크를 삽입하였다. 워터마크는 의사 랜덤 시퀀스(Pseudo Random Sequence)로 구성되어 있고 워터마크의 검출은 Cox의 유사도 측정식을 이용하여 워터마크의 삽입여부를 판단한다

공공기관의 행정서비스품질 평가에 관한 실증적 연구 : 서울시 구청 중심으로 (An Empirical Study on Evaluation for Administrative Service Quality of Public Institution : Focused on District Offices in Seoul)

  • 박경호;이강인
    • 한국컴퓨터정보학회논문지
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    • 제14권9호
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    • pp.167-177
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    • 2009
  • 서비스품질이 기업들뿐만 아니라 공공부문에서도 재고되어지고 있는 이 시점에서 기업들의 고객중심적 서비스 품질 접근방식을 공공부문에서도 많은 관심을 가지게 되었다. 하지만 공공기관의 비즈니스 문화의 차이로 인하여 서비스품질을 개선하는 것에는 많은 애로사항이 있으며 또한 서비스 개념에는 무형성, 이질성, 비분리성 및 소멸성이 포함되어있기 때문에 서비스품질을 객관적 이게 평가하기란 매우 어려운 일이다. 따라서, 본 연구에서는 주관적 환경에서 보다 객관적이게 서비스품질을 평가하기 위해 퍼지이론과 AHP 모형을 통합한 ASQI모형을 개발하였다. ASQI모형에서의 퍼지이론은 인간의 주관적 판단과 관계되는 애매한 개념들을 평가하는데 이용되어졌고, AHP모형은 고객들이 중요하게 고려하는 서비스품질 평가요인(유형성, 신뢰성, 대응성, 확신성, 공감성)들에 대한 중요도를 파악하기 위하여 이용되어졌다.

다원주의 시대에서 대순사상의 세계시민성 가치연구 (A Study on the World Citizenship Values of Daesoon Thoughts in the Era of the Plural Society)

  • 김용환
    • 대순사상논총
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    • 제23권
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    • pp.345-383
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    • 2014
  • This article intends to examine the value of the world citizenship in the perspective from the root meaning that is stressed as the behavior style of Daesoon thoughts in relation with 'desirable attitude of life in education of morality. Traditional root meaning of Daesoon thoughts turned out to be proper moral behavior principle such as Yin Yang harmonious virtue, God Humane keeping unity, and conviviality with regrets settlement. Such three principles of Daesoon Thoughts show the characteristic of global code such as respect of life, solidarity unity, and tolerant trust. To revise the phenomenon of duality, and to realize the human awakening in radically changing reality, we need to cultivate world citizenship based on the root meaning of Daesoon thoughts. Daesoon thoughts covering the East and the West, especially the key features of religion, can cultivate the world view of citizenship in the era of plural society based on folk beliefs toward Gucheon Sangje faith as the essence of the multiplism. The world citizenship of human society is necessary to unite the world in the unified construction cooperative spirits. All beings need to be away from antagonistic confrontation with the practice of mutual conviviality. The diameter of acquired joining world citizenship can have the opportunity to realize of Gucheon Sangje's Heaven and earth construction. The root meaning of Daesoon thoughts can contribute to moral practicality with world citizenship by practice of heavenly truth and human truth. First, cultivating heavenly truth by means of insight can develope the profound world citizenship. Secondly, the solidarity of the public and private can cultivate public citizenship. Thirdly, in the crisis of the mankind, this awakening conviviality can be foundation for world citizenship of public communication. Fourthly, the spirit that would not deceive ownself can be contributed to cultivating the world citizenship by means of the process of internalizing Daesoon thoughts. Nowadays in the plural society demanding world citizenship, the public citizenship can deepen the spirit of respect of life, solidarity unity, and tolerant trust in the process of world citizenship cultivation. In the future, the world citizenship can be deepen the alternative of practice in the continuous cultivation of world citizenship. In this process, we can form the culture of coexistence which can contribute to human society as well as korean society by developing the value of living together happiness through the guide of this phonesis.