• Title/Summary/Keyword: Basic Concept

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A Snubber Circuit for Flying Capacitor Multilevel Inverter and Converter (플라잉 커패시터 멀티레벨 인버터 및 컨버터를 위한 스너버 회로)

  • 성현제
    • Proceedings of the KIPE Conference
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    • 2000.07a
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    • pp.448-451
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    • 2000
  • This paper proposed a snubber circuit for flying capacitor multilevel inverter and converter. The proposed snubber circuit makes use of Undeland snubber as basic snubber as basic snubber unit and has such an advantage of Undeland snubber used in the two-level inverter. Comparing conventional RCD/RLD snubber for multilevel in verter and converter the proposed snubber keeps such a good features as fewer number of components improved efficiency of system due to low loss snubber and reduction of voltage stress of main switching devices due to low overvoltage. Furthermore the proposed concept of constructing a snubber circuit for flying capacitor 3-level inverter and converter can apply to any level of them. In this paper the proposed snubber applies to three-level flying capacitor inverter and demonstrates its feature by computer simulation and experimental result.

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A Study on the condition of the children's facility in grand bookstores (국내대형서점내의 아동서적공간 현황에 관한 연구 - 서울지역 대형서점을 중심으로 -)

  • Kim, Dae-Hyun;Han, Hae-Ryon
    • Proceedings of the Korean Institute of Interior Design Conference
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    • 2006.05a
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    • pp.119-124
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    • 2006
  • The purpose of this study is to provide basic guidelines for qualitatively advanced children's facilities and spaces in grand bookstores. The main concept is considered with a situation that grand bookstores of large corporations are increasing in quantity, but their social missions for the user are often being connived. The study is performed by research of current six domestic grand bookstores, two branches of each three large corporations, larger than 2,500py in Seoul, and the research is applied to Murtha's User Benefit Criteria as a basic format. As a result of the research, some problems to be improved are detected in ways of behavioral facilitation, physiological maintenance, perceptual maintenance, and social facilitation, therefore findings in survey turned out to be parents' dissatisfaction in many aspects. Finally, with this result, it is desirable for interior designers to reflect the indicated insufficient elements to their following children's bookstore space design for the user, children and their parents.

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A Basic Study on Development of Merchant Ship's Security System in High-Risk Terrorism (고위험 테러시대 선박보안시스템 구축을 위한 기초 연구)

  • 이은방
    • Proceedings of KOSOMES biannual meeting
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    • 2003.05a
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    • pp.17-22
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    • 2003
  • With the terrorist attacks on 11 September 2001, the ships and their crews' safety and security have become a major issue in the maritime industries. In high-risk terrorism. not only ship owners and port authorities but also crew members on board should take precautions in the conduct of their business. In this paper, the vulnerability and essential elements in overall security of merchant ship are analyzed with a discussion in depth of the concept and principles of maritime security management. Author proposes ship's security model to reduce security risk and to minimize damage as a basic study for designing security system for merchant ship.

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Educational Program Model of Housing Welfare (주거학 전공자를 위한 주거복지 교육 프로그램 모델 개발 기초연구)

  • Park Nam-Hee;Choi Jae-Soon
    • Journal of the Korean housing association
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    • v.17 no.3
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    • pp.89-98
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    • 2006
  • The purpose of this study was to survey curriculum of the department of housing and to develop housing welfare educational program in order to offer the information helpful to the professional of housing education and housing policy makers. Documentary research and content analysis methods were used in this study. Data drawn from internet homepage of each universities and public institutions. The major results of this study are as follows. 1) There were 30 universities which has related to the department of housing and the name of major was very various. The half of their curriculum were housing and interior design. 2) The housing welfare educational program should be step by step. The first is basic step to team basic theory of housing and to establish concept of housing welfare. The second is application and practice step of housing design and housing policy and housing economics. The third is specific application step to consider that who were taker from the housing welfare policy and to take practical training in field.

Development of TTX(Tilting Train Express)for speed-up the existing main line (한국형 기존선 고속화 틸팅열차 연구개발사업)

  • Song Dal-ho;Choe Kangyoun;Han Seong-ho
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2004.10a
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    • pp.3-5
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    • 2004
  • In order to speed up basic concept is to enhance high speed, curve limit speed, cross limit speed, acceleration/deceleration speed. It is important to optimal interface fundamental technology of vehicle, rail, electrical power, and signal system. Tilting train has advantage minimizing investment cost of infra railway system for increasing train limit speed in curve. the developed tilting train should be operated to commercial service speed 180Km/h of 200Km/h at KNR upgrade railroad. This paper proposed the basic model of system engineering for developing of TTX, tilting EMU (maximum operation speed : 180km/h) with speed-up of conventional railway system.

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Study on Basic Performance Test of Electroosmotic Pump with Porous Glass Slit. (다공성 유리 슬릿 EO펌프 기초 성능 측정 연구)

  • Seo, Sang-Tae;Park, Cheol-Woo
    • 한국가시화정보학회:학술대회논문집
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    • 2007.11a
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    • pp.59-62
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    • 2007
  • The basic concept and preliminary performance results of a miniaturized electroosmotic (EO) pump with diaphragms were included in the present study. The separation of an electroosmotic pumping liquid from a drug using diaphragms is mainly to have a freedom in choosing an electroosmotic pumping liquid and to achieve the optimal drug delivery, and, preferably its precise control. We performed maximum flow rate, maximum pressure, and maximum current measurements with and without diaphragm designs. As a result, the effect of diaphragms on pump performance at the maximum condition is small. However, the presence of diaphragms does not allow indefinite continuous pumping.

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Quantitation of In-Vivo Physiological Function using Nuclear Medicine Imaging and Tracer Kinetic Analysis Methods (핵의학 영상과 추적자 동력학 분석법을 이용한 생체기능 정량화)

  • Kim, Su-Jin;Kim, Kyeong-Min;Lee, Jae-Sung
    • Nuclear Medicine and Molecular Imaging
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    • v.42 no.2
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    • pp.145-152
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    • 2008
  • Nuclear medicine imaging has an unique advantage of absolute quantitation of radioactivity concentration in body. Tracer kinetic analysis has been known as an useful investigation methods in quantitative study of in-vivo physiological function. The use of nuclear medicine imaging and kinetic analysis together can provide more useful and powerful intuition in understanding biochemical and molecular phenomena in body. There have been many development and improvement in kinetic analysis methodologies, but the conventional basic concept of kinetic analysis is still essential and required for further advanced study using new radiopharmaceuticals and hybrid molecular imaging techniques. In this paper, the basic theory of kinetic analysis and imaging techniques for suppressing noise were summarized.

Development of Spur Gear Design Software using Tooth Profile Modification (치형수정 기술을 이용한 스퍼기어설계 소프트웨어의 개발)

  • Kim, Tae-Wan;Hwang, Jin-Yeong;Jo, Yong-Ju
    • Journal of the Korean Society for Precision Engineering
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    • v.19 no.10
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    • pp.202-211
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    • 2002
  • The basic concept of 'tooth profile modification' to change a part of the involute profile to reduce the load in that area and appropriate profile modifications can help gears to run quietly and resist scoring, pitting and tooth breakage. In this study, the modification of tooth profile to make a smooth transmission of the normal loads in spur gears has been developed. The modified tooth profile has been determined by the total deflection at contact points. We use the AGMA Standard to design basic gear profile. We also developed a gear design program using tooth profile modification.

Formulation of DNC (Direct Numerical Control) system for controlling flexible manufacturing system (FMS 제어를 위한 DNC 시스템의 형성에 관한 연구)

  • 이병룡;이석희
    • 제어로봇시스템학회:학술대회논문집
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    • 1987.10b
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    • pp.242-248
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    • 1987
  • Recently, a quite large number of investigation is published on the subject of Flexible Manufacturing System which can cope with the volatile market demand and the variety of product. Minimum requirement of designing FMS is depicted and by investigating the communication system between the machine tool and the cell control computer, ana between the central computer and the cell control computer, when it is formed as a sub-system of an FEM, the software can be evolved to the control software of the total Flexible Manufacturing System. It is developed the communication system between the central computer and the cell control computer which is the basic structure of the control architecture of FMS under the concept of DNC (Direct Numerical Control). It is used CYBER 180-830 as the central computer, and GMC-1100 computer as the cell control computer, and the main basic program is developed and tested, thus forming a DNC system which can be used in educational environment.

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Educational Strategies for Clinical and Technical Skills Performance (진료와 술기 수행의 교육전략)

  • Roh, HyeRin
    • Korean Medical Education Review
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    • v.18 no.3
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    • pp.132-144
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    • 2016
  • The aim of this study is to provide the background of developing guides to clinical performance and basic clinical skills and to introduce how to teach and learn using the guide. The students' performance problems presented in an objective clinical skills examination were disease-centered tertiary hospital clinical care, incomplete performance, doing by rote, and an exam-oriented learning attitude. The problems were caused by a tertiary hospital-based educational environment as well as schools and faculty who are unfamiliar with the concept of patient-centered care. The purpose of the guide to clinical performance and basic clinical skills is to overcome these problems and address the causes. The guides show a clinical presentation approach to primary care; clinical care integrated with knowledge, skills, and attitude; a schematic approach; and a patient-centered attitude. To achieve these goals, a strategy to change the educational culture is important. Curricular reform, faculty development, and improving educational facilities and environments are suggested.