• 한국철도학회논문집
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• 제17권1호
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• pp.7-13
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• 2014

팬터그래프와 전차선 사이의 이선을 유발하는 주요 요인은 팬터그래프로 인하여 전차선에 야기되는 파동의 전파와 반사 그리고 열차 진행방향의 전차선로 강성변화이다. 본 논문의 목적은 200km/h급 일반철도와 300km/h급 고속철도에서 이선을 효과적으로 줄이기 위하여 앞서 언급하였던 두 가지 요인 중에서 어느 쪽을 중요하게 고려해야 하는지를 분석하는 것이다. 고속철도 경우에는 파동의 전파와 반사가 강성 변화에 비하여 집전성능에 영향을 더 크게 미친다. 증속을 위해서는 드로퍼 경량화와 전차선 고 장력 부여를 위한 고 강도 전차선 개발이 필요하다. 파동전파속도를 향상하기 위하여 조가선의 장력을 증가시키면 오히려 집전성능을 악화할 수 있음에 유의해야 한다. 200km/h급 일반철도의 경우에는 전차선로 강성 변화가 파동 전파 및 반사에 비하여 집전성능에 영향을 더 미치므로 강성변화를 완화시키기 위하여 경간길이 축소, 전차선로의 장력 증가 및 드로퍼배치 최적화가 필요하다.

• 한국도서관정보학회지
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• 제48권4호
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• pp.303-320
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• 2017

이 연구는 공공도서관을 건립하고 개관하는 과정에서 새롭게 구축되는 개관장서 구성의 방법론에 대하여 논하고 있다. 최근 지역자치단체 등이 공공도서관을 지속적으로 설립하고 있는 것은 매우 고무적이다. 반면, 도서관의 가장 중요한 요소인 장서구성에 대한 방법론이 정립되어 있지 않아 일선에서는 혼선의 여지가 있다, 이에 따라 이 연구에서는 최근 개관한 10개 공공도서관의 개관장서 구축 사례를 검토하여 장서개발정책 수립, 장서구성기본계획 수립, 개관장서 규모 도출, 그리고 향토자료 구축 방안 등의 측면에서 표준적인 공공도서관 개관장서 구축방안을 모색하고자 하였다.

• 전기학회논문지
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• 제62권12호
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• pp.1803-1808
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• 2013

To maintain contact between catenary and pantograph copper is important in order to transmit power smoothly on Current collection system. But, Arc discharge with strong light is generated because of contact loss. Therefore, Arc discharge detection is important measurement factor judging performance of current collection system. In this paper, It is described to results of arc discharge applying UV detection technology using arc generator. And Arc discharge was detected using the most commonly used processing catenary and rigid catenary and pantograph copper of electric rolling stock for securing arc detection instrument reliability. Results of contact loss detection instrument in this paper will be used for maintenance of current collection quality and system.

• 전기학회논문지
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• 제63권6호
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• pp.855-859
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• 2014

Quality criteria for interaction between a pantograph and overhead contact wire is a most important requirement to assess of the performance for the current collection system. Interaction performance between pantograph and catenary system is subject to approval by the infrastructure manager when a new design and contraction of overhead contact line and pantograph are installed. Among the various performance, percentage of arcing at maximum line speed is a simple test method compared with contact force of pantograph due to direct sensing of pantagraph, calibrations, installations of train, and etc. On the other hand, percentage of arcing is need to reliable arcing detector and general requirements with accordance with EN 50317. In this paper, percentage of arcing are investigated on the function of duration of arc and proposed which is satiable of percentage of arcing. As a results, we proposed which duration of arcs are unsuitable from infrastructures point of view as performance testing for quality of current collection.

• 한방안이비인후피부과학회지
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• 제13권2호
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• pp.182-187
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• 2000

Current status and quality administration of botanical products in America which has one of the biggest market need to be analyzed for the internationalization of oriental medicine. In this study, current status of botanical products as dietary supplements was analyzed and quality adminstration by United States Pharmacopoeia and National Formulary(USP-NF) was compared with The Korea Pharmacopoeia and botanical drug standard collection(KP), Even though the number of botanical products in USP-NF is small, it is rapidly increasing and more detailed compared with KP. Especially, reference standard compound should be determined for each botanical drugs, and more detailed standard for other items should be established in KP considering international trends. Though the history of botanical drugs in America is short, its annual market is about 3.2 billion dollar, so American administration system should be examined carefully for the internationalization of oriental medicine and related industry.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.3052-3058
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• 2011

A high-speed train is the system that the electric power is supplied through the overhead contact line and drives motors. In this case that the de-wiring beteen the overhead contact line and the pantograph of a high-speed train, the occasion that smooth power supply is not accomplished occurs sometimes. If the de-wiring occurs, the arc discharge may damage the overhead contact line or the pantograph, and the falling-off in power quality may cause the damage and malfunctioning of motor block. This paper presents the methodology that the arc discharge by de-wring between overhead line and pantograph is discriminated through measuring the PT and CT in the vehicle, and measures the current collection characteristics for a high speed train.

• 전기학회논문지
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• 제61권8호
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• pp.1216-1220
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• 2012

The current collection between pantograph and contact wire is a more critical component for need to train speed up in electric railway. The basic purpose of this paper is to establish a measure of determining arc by developing an arc detector assessment system. The system was designed under conditions of EN 50317 and simulations were conducted using the developed device. According to the results, it was possible to conduct certification tests following regulations of international standards. To check the validity of our approach for the intended application, we analysis contact loss of catenary system using developed arcing measurement system in Korea. The proposed arcing measurement system is expected to enhance precision of current collection quality performance assessment methods at high-speed lines and conventional lines.

• Current Research on Agriculture and Life Sciences
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• 제32권4호
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• pp.175-177
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• 2014

This is the first report describing the seasonal conditions affecting shoot regeneration by the chrysanthemum cv. Baeksun. The shoot regeneration from petal explants was found to be more favorable from September to December, reaching the highest values in December. In addition, the quality of the shoots was also influenced according to the season of the explant collection, where healthy and uniform plants were derived from the explants collected in December. Choosing the proper season for explant collection affected the successive plant growth parameters (i.e., plant height and fresh weight). Thus, the current results strongly suggest that season plays an important role in plant tissue culturing, which is an essential tool for micropropagation and Agro-bacterium-mediated genetic transformation studies.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 추계학술대회 논문집
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• pp.557-570
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• 2000

It is necessary to perform a study on the interrace between a G7 pantograph and a KTX catenary system prior to G7 on-line tests in the Korea High Speed Test Track in order to predict how high current collection quality can be obtained during the on-line tests and check if safety problems shall be caused b)Y the tests or not. According to the simulation results, current collection quality of the G7 pantograph at 350km/h is lower than that of a GPU pantograph at 300km/h, but the contact wire uplifts and average contact forces are within the safe-zone. In addition, the ratio of running speed (350km/h) to safe running. Therefore, the G7 on-line tests at 350km/h in the Korea High Speed Test Track is expected not to cause the safety problem.

• 한국도서관정보학회지
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• 제52권2호
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• pp.167-188
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• 2021

국가도서관은 한 국가의 지식문화유산인 국가장서를 집중적으로 개발·보존하고 제공해야할 책무가 있다. 특히 국립중앙도서관의 사명을 완수하기 위한 4대 목표 가운데 '국가지식자원 접근·보존 기반 고도화'를 이루기 위해서는 외연적 범위를 국내자료뿐 아니라 외국자료로도 확대하여 국가지식자원을 강화할 필요가 있다. 즉, 국내에서 생산되는 최신자료와 소급자료를 최대한 수집·제공·보존하는 기능은 물론이며 외국에서 생산·유통·보존되고 있는 고품질 학술자료 및 한국과 관련된 자료를 가능한 한 많이 수집하여 국가지식정보센터로서의 기능을 수행해야 한다. 본 연구는 선진국 국가도서관의 외국자료 수집 및 서비스 현황을 조사·분석하여 시사점을 도출하였다. 이를 바탕으로 현재 국립중앙도서관의 외국장서 수집수준을 비교·평가한 다음 고품질 학술자료 및 한국 관련 외국자료를 최대한 확보하기 위한 전략을 제시하는데 본 연구의 목적이 있다.