• 전기학회논문지
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• 제64권6호
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• pp.857-863
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• 2015

OF cable with excellent reliability and economic efficiency, has been used as the main cable of underground transmission in Korea. However, as XLPE cable is excellent in view points such as reduction of loss, convenience on the construction/operation, and manufacturing technology, it has been replaced as instead of OF cable. Also, when the aging occurs in some sections of OF cable, the section is replaced as XLPE cable without changing of whole cable line. However, there are some differences like electrical constants between both types of cables. Therefore if underground transmission system will be operated as combined connection composited of both cables, it should be proved that overvoltage is stable in steady and transient state. This paper describes the effectiveness of connection operation in combined OF and XLPE cable. For the evaluation of effectiveness, some important analysis such as sheath component voltage, lightning and switching overvoltage, single line-to-ground fault are carried out in steady and transient state. EMTP/ATPDraw is used for modeling and analysis of system.

• 전기학회논문지
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• 제61권1호
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• pp.41-49
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• 2012

This paper describes the operation mode development for the grid-tied PMSG(permanent magnet synchronous generator) wind power system combined with a battery energy storage. The development of operation modes was carried out through simulations with PSCAD/EMTDC software and experiments with a 10kW hardware prototype. The detailed simulation models for PMSG wind power system and battery energy storage were developed using user-defined models programed with C-code. A 10kW hardware simulator was built and tested in connection with the local load and the utility power. The simulation and experimental results confirm that the grid-tied PMSG wind power system combined with battery energy storage can supply highly reliable power to the local load in various operation modes.

• Journal of Chest Surgery
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• 제15권4호
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• pp.394-401
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• 1982

Recently, 4 cases underwent successful surgical correction of tetralogy of Fallot combined with pulmonary atresia in 2 cases, with abnormal coronary artery in another 2 cases. The operation consisted of a patch repair to the ventricular septal defect. The pulmonary atresia and stenosis were corrected with the method of external connection, from the right ventricle to the pulmonary artery using the valved conduits.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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• pp.313-316
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• 2006

As Decentralized Generation(DG) becomes more reliable and economically feasible, it is expected that a higher application of DG units would be interconnected to the existing grids. This new market penetration of DG technologies is linked to a large number of factors like technologies costs and performances, interconnection issues, safety, market regulations, environmental issues or grid connection constrains. Korea Electric Power Corporation (KEPCO) has researched performance characteristics of the 60k W class 1) basic start-up & shutdown operation analysis 2) interconnection test 3) MGT -absorption chiller-heater system in the local condition. Variations of heat recovery from exhaust gas has measured according to micro gas turbine output of 15, 30, 45, 60kW. From those results, the performance of the MGT-absorption chiller/heater system has been evaluated. The suggested strategy and experience for the evaluation of the distributed generation will be used for the introduction of other distributed generation technologies into the grid in the future.

• 신재생에너지
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• 제2권3호
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• pp.15-22
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• 2006

As the distributed generation becomes more reliable and economically feasible, it is expected that a higher application of the distributed generation units would be interconnected to the existing grids. This new market penetration using the distributed generation technology is linked to a large number of factors like economics and performance, safety and reliability, market regulations, environmental issues, or grid connection standards. KEPCO, a government company in Korea, has performed the project to identify and evaluate the performance of Micro Gas Turbine(MGT) technologies focused on 30, 60kW-class grid-connected optimization and combined Heat & Power performance. This paper describes the results for the mechanical, electrical, and environmental tests of MGT on actual grid-connection under Korean regulations. As one of the achievements, the simulation model of Exhaust-gas Absorption Chiller was developed, so that it will be able to analyze or propose new distributed generation system using MGT. In addition, KEPCO carried out the field testing of the MGT Cogeneration system at the R&D Center Building, KEPCO. The field test was conducted in order to respond to a wide variety of needs for heat recovery and utilization. The suggested method and experience for the evaluation of the distributed generation will be used for the introduction of other distributed generation technologies into the grid in the future.

• 융합정보논문지
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• 제7권6호
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• pp.181-186
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• 2017

최근 아이들의 창의력 학습 및 놀이에 로봇이 활발하게 이용되고 있지만 대부분 로봇이 정형화된 형태를 가지고 있으며 프로그램의 의존도가 높아 창의력 학습 및 놀이에 어려움이 있다. 우리는 이러한 단점을 보완하기 위해 정형화 되지 않은 모듈 형태의 로봇구조를 가지고 있으면서 결합을 쉽고 안정적으로 할 수 있도록 하였고 하나의 버튼을 이용하여 사용자가 원하는 동작을 기억시키고 기억된 동작을 똑같이 재생하는 로봇을 제작 하였다. 또한 모듈 사이를 무선으로 연결하고 정보를 공유하여 다수의 모듈이 결합 되었을 경우 어느 모듈에서나 버튼을 한번 누르면 결합된 모든 모듈의 동작을 쉽게 조정할 수 있도록 하였다. 실제 동작을 검증하기 위해 두 개, 3개 및 5개의 모듈을 결합하여 자벌레 동작과 보행 로봇을 구현하여 제안된 구조와 알고리즘의 유용성을 보였다. 향 후 무선연결 방법을 보완하여 인터넷상에서 통제할 수 있는 지능화된 모듈라 로봇의 연구가 필요하다.

• Journal of Chest Surgery
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• 제18권4호
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• pp.806-811
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• 1985

Pulmonary arteriovenous fistula is a rare congenital vascular malformation in the lung, resulting from erroneous capillary development, with incomplete formation or disintegration of the vascular septa that would normally divide the primitive connection between the venous and arterial plexus. The pathogenesis of its symptom is that unoxygenated and desaturated arterial blood enter into the pulmonary venous system directly. Recently we have experienced a case of multiple pulmonary arteriovenous fistula in a 15 year old male patient, who presented the symptom of cyanosis and dyspnea on exertion. The operation revealed well circumscribed and multilobulated aneurysmal lesion in left lower lobe with its subpleural and posterolateral basal location, and another aneurysmal lesion in inferior lingular segment of left lung. There was no abnormal connection between the fistula and systemic circulation. The left lower lobectomy was performed along with local extirpation of the inferior lingular segment of left lung. Both lesions showed angiomatous dilatation of the various sized vessels embedded in the parenchyma microscopically. Postoperative clinical course disclosed much improvement in symptoms and in the value of blood gas analysis. The patient was discharged without any complication.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.585-588
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• 2007

As the distributed generation becomes more reliable and economically feasible, it is expected that a higher application of the distributed generation units would be interconnected to the existing grids. This new generation technology is linked to a large number of factors like economics and performance, safety and reliability, market regulations, environmental issues, or grid connection constrains. KEPCO (Korea Electric Power Corporation) is performing the project to develope the Distributed Micro Gas Turbine (MGT) technolgies by using Swine BIO-ENERGY. This paper describes the plans and strategies for the renewable energy of MGT on actual grid-connection under Korean situations. KEPCO also, has a research plan on bio-gas pretreatment system applicable to our domestic swine renewable resources and is performing concept design of pilot plant to test grid operation. In addition, this testing will be conducted in order to respond to a wide variety of needs for application and economic evaluation in the field of On-site generation.

• 한국철도학회논문집
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• 제14권5호
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• pp.461-469
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• 2011

국내 중소도시 KTX와의 연계교통이 부족하여 정시성 확보가 어려운 점을 고려하여 중소도시 KTX와의 연계버스를 확충하고 연계버스 이용자의 편리성과 승차감을 높이는 합리적인 버스 디자인 가이드라인과 철도교통정책을 제안한다. 이에 따라 연계버스의 합리적인 디자인을 위해 버스이용 조건과 버스시설별 디자인 고려사항 그리고 버스운행업체의 관련된 관계법규 및 제한조건을 조사 분석하여 버스 디자인 가이드라인을 정한다. 또한 연계버스 운행의 실용화가 가능토록 연계버스의 디자인 가이드라인을 적용한 실용화시스템 요소의 최적화 방법론을 제시한다. 끝으로 중소도시 KTX와 연계교통수단으로서의 버스 디자인 가이드라인과 연계버스 운행에 따른 철도교통정책을 제안한다.

• Journal of Chest Surgery
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• 제13권4호
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• pp.442-447
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• 1980

A 8-year-old boy underwent surgical correction of complete transposition S.D.D. of great arteries combined with subaortic ventricular septal defect and pulmonary stenosis [infundibular and valvular]. The operation consisted of an internal baffling connecting the left ventricle to the aorta through the ventricular septal defect. The pulmonary stenosis was corrected with the method of external connection, the right ventricle to the pulmonary artery using the conduit valve [20 mm] contained Hancock due to abnormal distribution of left coronary artery of which conduit due to abnormal distribution of left coronary artery of which the circumflex branch crossed the portion of right ventricular outflow tract. This case was suitable for corrective surgery-Rastelli operation-and the patient`s condition in very good until present [post-operative 5 months].