• Title/Summary/Keyword: 다원

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Methodology for optimum design of surge relief valve in water distribution system (상수관망에서 서지 릴리프밸브의 최적 설계 방법론)

  • Kim, Hyunjun;Hur, Jisung;Kim, Geonji;Baek, Dawon;Kim, Sanghyun
    • Journal of Korean Society of Water and Wastewater
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    • v.31 no.1
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    • pp.1-6
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    • 2017
  • Surge pressure is created by rapid change of flow rate due to operation of hydraulic component or accident of pipeline. Proper control of surge pressure in distribution system is important because it can damage pipeline and may have the potential to degrade water quality by pipe leakage due to surge pressure. Surge relief valve(SRV) is one of the most widely used devices and it is important to determine proper parameters for SRV's installation and operation. In this research, determining optimum parameters affecting performance of the SRV were investigated. We proposed the methodology for finding combination of parameters for best performance of the SRV. Therefore, the objective function for evaluate fitness of candidate parameters and surge pressure simulation software was developed to validate proposed parameters for SRV. The developed software was integrated into genetic algorithm(GA) to find best combination of parameters.

A Study on MAC Protocol for Packet Data Service in Slotted CDMA Environment (Slotted CDMA 환경에서 패킷 데이터 서비스를 위한 MAC 프로토콜 연구)

  • 임인택
    • Journal of Korea Multimedia Society
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    • v.7 no.2
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    • pp.204-210
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    • 2004
  • This paper proposes a transmission probability control scheme and MAC protocol for packet data services in slotted CDMA system. In slotted CDMA system, multiple access interference is the major factor of unsuccessful packet transmissions. Therefore, in order to obtain the optimal system throughput, the number of simultaneously transmitted packets should be kept at a proper level. In the proposed protocol, the base station calculates the packet transmission probability of mobile stations according to the offered load and then broadcasts it. Mobile stations, which have a packet, attempt to transmit packet with the received probability. Numerical analysis and simulation results show that the proposed scheme can offer better system throughput than the conventional one, and guarantee a good fairness among all mobile stations regardless of the offered load.

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About the character of next generation in the poly-generous ploy copulation. (동종품 교배와 이품종 교배를 교번한 이중교배의 차대 잠형질에 관한 연구(IV) -다원다교배와 차대잠 형질-)

  • 김윤식
    • Journal of Sericultural and Entomological Science
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    • v.7
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    • pp.43-47
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    • 1967
  • The author studied on the character of next generation which was laid from poly copulated female moth. The obtained results are as follows; 1. In the three generous two copulation, selectivity of fertilization and copulating order of silkworm showed like the two generous double copulation and their intensity of fertilization was characterized in the next generation. 2. In the next generation of silkworm, new form and character were not occurred through polygenerous poly copulation. 3. Copulating time influenced on the next generation and the time was related closely tn the copulating type (copulating order) in the three generous two copulation which was differed each copulating time.

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A Study on the Variation in Meaning of Architectural Light since Modern Architecture (근대건축 이후 건축적 빛의 의미변화에 관한 연구)

  • 김경재
    • Korean Institute of Interior Design Journal
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    • no.25
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    • pp.213-220
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    • 2000
  • The meaning of light is not always developed aspect in process of architecture history as essence worth of the architecture. It means that architectural light is not affected simple development of civilization, but it has more complex aspect. The technology of applying architecture has continuous development of society that light is possible to extend quantity by development of technology because light is component not simple material or tools but strong worthy aspect, quality development of architecture comes true by exact understanding and application. Conversion from medieval society to modern society begins at the Industrial Revolution has new skills and materials, the architectural conform general space filled with non-characteristic light, and it gives rising to pursuit Utopia is not exist frequently. In result, light of metaphysical meaning is diminished and exterminated. In other hand light seems to be tools by development of technology in modern society, recovering its own meaning in other aspect. That light makes perfect image of architecture not by finite meaning only for simple space but by expressing strongly point that unify the whole architectural composition. Light is free from partial material of architecture. Light activates major composition through high-technology, and has possibility to carry out the essential worth animate architecture. The light expresses relative speciality for sense of place recognizes major component which the human being lives in and conform the real meaning of architecture.

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태양전지 interconnect ribbon용 Sn-Bi계 무연솔더 연구

  • Gang, In-Gu;Kim, Hyeok-Jong;Kim, Do-Hyeong;Kim, Jin-Sik;Kim, Hyo-Jae;Won, Su-Hyeon;Jo, Seong-Hun;Lee, Sang-Gwon;Ha, Jeong-Won;Choe, Byeong-Ho
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.05a
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    • pp.113.2-113.2
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    • 2011
  • Sn-Ag계 합금은 대표적인 무연 솔더 조성으로 전자제품의 실장 및 접합에 적용되어 왔으며, 태양전지 분야에서도 모듈의 전극과 bus바로 사용되는 등 다양한 분야에서 사용되고 있다. 그러나 최근 Ag 가격의 급격한 상승과 솔더 접합부의 신뢰성을 보다 향상시키고자 Ag의 함량을 줄이고 다원계 합금 조성의 무연 솔더 연구가 활발히 진행되고 있다. 본 실험에서는 기존의 연구 결과를 바탕으로 Sn-1.0Ag-0.5Cu-0.4In 4원계 무연솔더 조성에 Bi를 첨가하여 최적의 융점과 용융구간을 가지는 5원계 Sn-Ag-Cu-In-Bi 계 솔더 합금을 설계하였다. 이 설계된 합금은 기존의 유연 솔더인 Sn-Pb와 대표적인 무연 솔더인 Sn-3.5Ag와 각각의 특성을 비교 분석하였다. 젖음성을 평가하기 위하여 wetting balance tester를 이용하여 실험을 행하였고 Differential Scanning Calorimetry(DSC)를 분석하여 젖음 정도와 조성 분석 및 고상점과 액상점 등의 녹음 거동을 확인하였다. 또한 각각의 조성별 전단응력에 따른 파괴 거동을 분석하였다.

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A Case of Nocturnal Paroxysmal Dystonia: Frontal Lobe Epilepsy and Parasomnias (FLEP) Scale, Polysomnography and Subtraction of Ictal-interictal SPECT Coregistered with MRI (SISCOM) Findings (야간발작성근육긴장이상 1예: 전두엽간질 및 사건수면척도, 수면다원검사, 발작기 및 발작간기 감산 SPECT 소견)

  • Kim, Woojun;Oh, Yun-Sang;Yoon, Bora;Kim, Yeong-In;Lee, Kwang-Soo;Kim, Joong-Seok
    • Annals of Clinical Neurophysiology
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    • v.10 no.1
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    • pp.52-57
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    • 2008
  • Even though the origin and nature of nocturnal paroxysmal dystonia (NPD) remains unclear, it has been considered as a manifestation of the nocturnal frontal lobe epilepsy. We report a 17-year-old man with abnormal stereotyped movement during sleep. Video-EEG monitoring, ictal SPECT and night polysomnography did not show any evidence of epilepsy. However, the partial response to large dose of carbamazepine and the scoring according to the frontal lobe epilepsy and parasomnias (FLEP) scale suggest his events could be classified as epilepsy. Therefore we think the FLEP scale might be a useful tool for differential diagnosis in a patient presenting NPD.

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Evaluation of Quantitative Results of PIXE Analysis (다원소 동시분석법 PIXE법의 정량성 평가)

  • Park, Jeong-Ho;Choi, Kum-Chan
    • Analytical Science and Technology
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    • v.10 no.5
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    • pp.386-394
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    • 1997
  • The standard samples for the calibration of PIXE analysis were prepared using the single element standard samples and sulfur and chlorine compounds. The diluted standard solutions were dropped on the non-hole nuclepore film and dried. Standard sample of six elements of Ca, Cr, Co, Cu, Se and Sr had close agreement between the measurement and theoretical values. According to the theoretical study about the effects of thick samples on the accuracy of the PIXE analysis, the reduction of X-ray yields in the thick sample can not be neglected for the sample thicker than $100{\mu}g/cm^2$.

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A Semiotic Analysis of JTBC : Focusing on Significance of Ideology (드라마 <송곳>의 기호학적 분석 : 이데올로기적 의미를 중심으로)

  • Tae, Bora;Choi, Mideum
    • The Journal of the Korea Contents Association
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    • v.16 no.6
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    • pp.54-62
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    • 2016
  • This study conducted semiotic analysis of drama . Based on Paradigm, Syntagm concept, I apprehended the characteristics of descriptive structure of drama, characters and contemplated on ideology reflected in the drama. As a result, it has approaching method of Critical Pluralism which strongly exposes resistance ideology. The drama intensified Classical Ideology such as gender role, hero, and family ideology, also it consists of Humane Introspection Ideology such as self-understanding, mutual-understanding, and self-serving bias.

Quality Assurance in Polysomnography - A Korean experience and critical suggestions (수면다원검사의 정도관리 - 한국에서의 경험 및 제언)

  • Jeong, Do-Un
    • Quality Improvement in Health Care
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    • v.1 no.1
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    • pp.124-131
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    • 1994
  • Polysomnography is an essential methodology for diagnosing and following up sleep disorders and doing researches on human sleep. Sleep medicine, mainly with the utilization of polysomnographic techniques, has developed itself as one of the promising fields in the 21st century medicine. Korea is not an exception in importing and developing sleep medicine into the conventional medicine. However, it still remains to be clarified what polysomnography is for and how it should be done, considering the relatively recent introduction of sleep medicine into Korea. The author, being a board-certified sleep medicine specailist, having experienced spreading out sleep medicine within Korea for the past four years, and having recently set up a major sleep study facility in Korea at Seoul National University Hospital, attempts in this introductory critical article to review the essential issues related to quality assurance in polysomnographic study of human sleep. Also, unconditional introduction of "automated" sleep scoring system, which has been found to have significantly reduced reliability in various studies including the author's own, is critically reviewed. The author suggests that quality assurance and training program should be initiated and established by a responsible sleep medicine-related organization such as the Korean Association of Sleep Medicine and Psychophysiology.

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A Study on 'Cultural Diversity' Contents for a Global Citizenship Education from Social Studies (사회과에서 세계시민교육을 위한 '문화 다양성'수업 내용 구성)

  • Kim, Da-Won
    • Journal of the Korean association of regional geographers
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    • v.16 no.2
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    • pp.167-181
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    • 2010
  • The multicultural society under globalization have made an impact on the education since the end of 20th century. This study is for the theoretical approach and presentation of method about global citizenship education in globalization & multicultural society today. As an education which is suitable in the globalization & multicultural society I present 'cultural diversity' education. The 'cultural diversity' education for fostering global citizenship is needed to enhance the cultural sensibility while learning other cultures. The 'cultural diversity' education is having the values of human rights, fairness, diversity respect and living together. So I present the study lesson plans of 'cultural diversity' education for a global citizenship education from elementary school 6 grade social studies "Natural environments and cultures of world regions" chapter.

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