• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.891-898
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• 2009

A high rock embankment by means of dynamic compaction has hardly carried out in domestic area. For the successful accomplishment of such a high rock embankment, construction quality and measurement control are conducted. Plate loading tests are carried out to verify the bearing capacity and safety against the long term settlement. In addition, settlement of each layer is measured in order to verify the effect of dynamic compaction and to predict long term settlement.

• 전기학회논문지
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• 제59권7호
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• pp.1187-1193
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• 2010

This paper provides the methods for enhancing the stability with normal or emergency operating conditions in real power systems and copes with the unbalance of demand of reactive power due to the loss of facility, such as 765kV transmission line. In this paper, we focused on the maximum allowable transmission power(hereafter, MAXTP) in the metropolitan area. In order to increase the MAXTP, the application of reactive power compensators, SVC, and Shunt compensator and reactor, is analyzed as an enhancing method of stability and MAXTP. Particularly, the f-V analysis was performed for the postulated contingency, in order to evaluate the effects on SVC. Conclusively, the stability of power systems could be enhanced and the MAXTP is increased effectively with Dongseoul SVC which has the capacity 200MVAr.

• 대한기계학회논문집
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• 제18권1호
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• pp.85-92
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• 1994

With the wide application of fiber-reinforced composite meterial in aircraft space structures and robot arms, the design and manufacture of composite joints have become a very important research area because they are often the weakest areas in composite structure. In this paper, the torque transmission capacities of the adhesive tubular single lap joint and double lap joint were studied. The stress and torque transmission capacity of the adhesive joints were analyzed by the finite element method and compared to the experimental results. The torque capacity of the double lap joint was increased 2.7 times over that of the single lap joint. Also, the fatigue limit of the double lap joint was increased 16 times over that of the single lap joint.

• 대한전기학회논문지:전력기술부문A
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• 제52권4호
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• pp.193-200
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• 2003

The use of underground transmission tables has continuously increased in densely inhabited urban and suburban area. Due to a increasing demand of underground cables, two or more circuits are installed in parallel for several kilometers. It, however, has not been realized that the sheath circulating current is generated in the system where a large number of cables are laid in the same route. In this paper, Author studied diversely the sheath circulating current on underground cables depending on the various length rate, the phase arrangement, and the grounding resistance of the sheath in the cross-bonded section. It was clear that very large circulating current is generated in cable systems due to unbalanced length rate and phase arrangement in the cross-bonded section.

• 대한전기학회논문지:전력기술부문A
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• 제55권5호
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• pp.191-194
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• 2006

Power system restoration following a wide area or complete blackout starts with energizing primary restorative transmission systems. During this primary restoration process, unexpected over-voltage may happen due to nonlinear interaction between the unloaded transformer and the transmission system. This is known as the harmonic resonance phenomenon that may cause burning out of transformer or other devices. Since the harmonic resonance originates from the nonlinear characteristics, it is very difficult to predict the occurrence of this phenomenon. This paper reports the analyses of the harmonic resonance occurred in domestic power system. Various analyses and results of the harmonic over-voltage is presented based on the PSCAD/EMTDC simulations.

• 전기학회논문지
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• 제59권11호
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• pp.1949-1955
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• 2010

This paper describes the characteristic and effectiveness of combined GIL transmission line through lightning surge analysis. In addition the XLPE cable is analyzed in the same condition to compare with GIL. Lighting surge analysis is carried out by EMTP/ATP-Draw to obtain overvoltage of GIL and XLPE cable at service-point and load-out area of underground line. Propagation velocity is calculated in combined transmission lines with GIL and XLPE cable. The overvoltage is also analyzed on GIL and XLPE cable with or without arrester operation. The Analysis results show that overvoltage of GIL is occurred higher than XLPE cable at the same condition. Therefore it is evaluated that the application of GIL at the field should be considered cautiously when more detailed transient analysis, another electrical testes and economic evaluations are implemented.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전력기술부문
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• pp.291-293
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• 2003

Energy markets of the Northeast Asia countries and in particular South Korea are perspective enough from the standpoint of export of energy resources from Russia. South Korea Power System has been rapidly growing. However, recently it has been confronted with difficulties in regard to constructing new Power Stations and especially Hydro Power Plants. Therefore it is mutually beneficial to build electric tie to South Korea in order to use highly effective Power of Northeast Asia. In this paper, we describe the maximum available transmission power through interconnected line without loss of stability in power system. For this simulation, the AC transmission system is assumed appropriate for this preliminary study. The transmission system will pass through territory of North Korea and connect to 765 kV Network near Seoul with long distance.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 A
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• pp.186-188
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• 2004

This paper describes the feasibility study of HVDC system application to KEPCO power system for increasing power transfer capability or the flexibility of power delivery from one area to the other using the existing transmission line. This paper assumes the 345kV transmission line connecting between Shinokchun and Sedaegu to be converted to the DC line by replacing the AC insulator with that of DC. Then, the HVDC bipole system of 1000MVA with $\pm300kV$ is designed and the contingency studies are carried out.

• Journal of Acupuncture Research
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• 제20권4호
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• pp.145-156
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• 2003

Objective : This study is to investigate the effect of electro-acupuncture ST36 on altered transmission of afferent somatosensory information caused by amyloid-${\beta}$(A-${\beta}$) that caused Alzheimer's disease. Methods : The effects of topical application of A-${\beta}$, A-${\beta}$ with ST36, aggregated A-${\beta}$(aA-${\beta}$), aA-${\beta}$ with ST36 and ST36 on the afferent sensory transmission to the neurons in the primary somatosensory(SI) cortex was observed in anesthetized rats. Quantitative determination of the effects of A-${\beta}$, A-${\beta}$ with ST36, aA-${\beta}$, aA-${\beta}$ with ST36 and ST36 was made by generating poststimulus time histogram of evoked response of individual cortical neuron by electrical stimulation of the receptive located in peripheral area(forepaw) Results : The results obtained in present study were summerized as follow : 1. Application of physiological concentrative 0.5 nM A-${\beta}$ caused afferent sensory transmission of SI cortex facilitated. 0.5 nM A-${\beta}$ with ST36 exerted much stronger effects than 0.5 nM A-${\beta}$ alone. 2. Application of $10{\mu}M$ A-${\beta}$ caused afferent sensory transmission of SI cortex unchangeable. But $10{\mu}M$ A-${\beta}$ with ST36 is facilitated at 30 min of post-drug period 3. Application of $10{\mu}M$ aA-${\beta}$ caused afferent sensory transmission of SI cortex diminished. $10{\mu}M$ aA-${\beta}$ with ST36 is diminished after 15min of post-drug period but is facilitated after 75min.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.510-510
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• 2012

반도체, 디스플레이, 태양광 등의 공정에서 사용되는 웨이퍼의 크기가 증가하고, 생산률이 플라즈마의 밀도에 비례한다는 연구 결과가 발표되면서 대면적 고밀도 플라즈마 소스 개발에 대한 연구가 활발히 진행되고 있다. 특히, ECR, ICP, Helicon plasma 등 고밀도 플라즈마 소스에 대한 관심이 높아지고 있다. 이에 따라, 여러 개의 ICP를 결합한 multiple ICP를 이용해 대면적 고밀도 플라즈마 소스 개발을 진행했다. Multiple ICP의 경우 각 ICP 소스에 같은 power (current)를 공급해야만 균일한 플라즈마 방전이 발생되어 균일도를 확보 할 수 있다. Current controller 같은 추가적인 장비를 설치하지 않고, power를 분배하는 transmission line을 coaxial 형태로 설계하고 같은 길이로 병렬 연결함으로써 각각의 ICP소스에서 균일한 플라즈마를 방전시킬 수 있었다. Power generator에서 보는 각 ICP의 total impedance는 각 ICP 소스의 impedance와 coaxial 형태의 transmission line의 characteristic impedance, frequency, 길이의 함수로 구할 수 있고, 이 total impedance가 일정하기 때문에 current가 균등하게 분배되어 각 ICP소스에 균등한 power 분배가 가능한 것이다. 실질적으로 ICP 소스의 impedance는 플라즈마 방전 유무에 따라 변화하기 때문에 일정하게 유지하는 것은 어렵다. Transmission line의 characteristic을 사용함으로써 ICP의 impedance의 변화에 상관없이 Total impedance를 일정하게 유지시킴으로써 균등한 power 분배가 가능하다는 것을 연구했다. Frequency는 13,56MHz, characteristic impedance를 $50{\Omega}$ (coaxial cable)으로 고정하고, ICP 소스의 플라즈마 방전 유무/antenna turn/소스 위치에 따른 total impedance를 transmission line의 길이에 따라 측정하고, 이를 이론값, 그래프와 비교하였다. 특정 length에서 플라즈마 방전 유무(ICP의 impedance 변화)와 상관없이 비교적 일정한 total impedance를 유지하는 것을 확인 했다. 이것은 특정 길이를 갖는 coaxial형태의 transmission line를 연결하면, total impedance는 플라즈마 방전 유무로 발생하는 ICP의 impedance 변화와 상관없이 일정하게 유지되어 각 ICP소스에 균등한 파워 분배가 가능하다는 것을 보여준 결과이다. 이것을 토대로 frequency에 따라(또는 characteristic impedance에 따라) 균등한 파워 분배가 가능한 coaxial 형태 transmission line의 특정 길이를 구할 수 있고, 대면적 소스에서 균등한 파워 분배를 위한 병렬연결에 적용할 수 있을 것이다.