• Fisheries and Aquatic Sciences
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• 제3권2호
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• pp.163-171
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• 2000

A series of numerical experiments are performed to examine the generation of inter-annual variations by an inertial current in an idealized semi-enclosed basin with dimension comparable to that of the East Sea. Model results indicate that the inter-annual variations dominate the kinetic energy spectrum with a peak around the time scales of 2-3 years. These variations are mostly due to the westward propagating meanders and large eddies induced by the instability of current, indicating their dependency on the eddy-resolving capacity of the model. They are generated in the interior of the basin but their energy is largely confined near the western boundary such that the east-west dimension of the basin cannot be considered as a critical factor as long as the basin covers enough western boundary region. Overall, this study suggests that the inter-annual variation observed in the East Sea is due to the meandering and large eddies induced by the instability of the current.

• 대한전기학회논문지
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• 제38권7호
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• pp.549-556
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• 1989

Radiation induced current of the insulating oil used for X-ray tube housing was investigated in this paper. The X-ray induced current increased in proportion to the X-ray intensity and X-ray wave length and was greatly affected by the temperature of the insulating oil and the gap length` however, the current was not varied by the amount of the X-ray absorbed. The results suggest that one must consider the following problems as important factors for X-ray machine design and normal operation: cooling system of the X-ray tube housing, X-ray intensity, increasing temperature due to continuous operation, years used, and oil exchange and management.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1410-1411
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• 2007

This paper analyses current densities induced inside a worker using AC arc welder. Applying the boundary element method, we calculate current densities induced in organs inside a worker in case he was located at 1[cm], 3[cm], 5[cm], 10[cm], 15[cm], 20[cm] far from a power cable of AC arc welder. As results of study, we find a maximum current density induces at a heart surface and may be higher than 10[$mA/m^2$] of ICNIRP guideline if he works within 15[cm] from a power cable.

• 전기전자학회논문지
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• 제23권1호
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• pp.230-234
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• 2019

본 논문은 펄스파워 동작시의 수백 ns의 대전류를 측정하기 위한 전류 센서의 개발과 특성평가 결과에 대하여 논하였다. 개발된 전류 센서는 펄스 파워 동작시 전류에 의해 발생되는 자속으로부터 유기기전력을 측정하도록 특별히 설계하였다. 개발 된 전류 센서의 출력 특성은 상업용 센서의 출력 특성과 매우 일치하였으며, 개발 된 센서의 출력 전압 검량선을 이용하여 빠른 펄스 파워의 실제 전류를 쉽게 검출 할 수 있음을 보였다. 따라서, 본 연구에서 개발 된 전류 센서는 실제적인 펄스파워 시스템에 적용할 수 있음을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전력기술부문
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• pp.46-50
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• 2004

This paper analysed the induced current density inside human body of hot-line worker for 765kV double circuit transmission line according to locations of human body Human was modelled by several organs, which included brain, heart, lungs, liver and intestines. We applied the 3 dimensional boundary element method to calculate induced electric fields.

• 한국해안해양공학회지
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• 제19권6호
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• pp.565-573
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• 2007

타원형 수중천퇴가 있는 지형을 통과하며 변형하는 파랑을 실험한 Vincent and Briggs(1989)의 불규칙파 실험조건을 수치모의하여 파랑과 흐름의 상호작용 효과를 연구하였다. 수치모의를 위해 SHORECIRC(흐름모형)와 REF/DIF S(파랑모형)를 결합한 모형과 파랑과 흐름을 동시에 계산하는 FUNWAVE를 이용하였다. 이 수치모의로부터 수중 천퇴상에서 발생된 쇄파류는 수중천퇴후면의 파 집중현상을 방해하고, 파랑을 천퇴중심축의 바깥쪽으로 굴절시켜, 파고를 상대적으로 감소시키는 역할을 하는 것을 확인할 수 있었다. 결합모형의 수치모의 결과는 쇄파류의 영향을 고려하지 않는 파랑모형만의 결과보다 실험치와 더 일치하였으며, FUNWAVE를 이용한 수치모의도 실험결과와 잘 일치하였다. 이는 파랑쇄파류의 파랑변형에 미치는 역할의 중요성을 확인시켜주는 것이다.

• 한국해양학회지:바다
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• 제8권2호
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• pp.164-176
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• 2003

하계 진동만에서 얻어진 영양염 DIN(dissolved inorganic nitrogen) 및 DIP(dissolved inorganic phosphate)의 분포는 이들 농도가 만안쪽에서 매우 높은 것이 특징이다. 또 표층(0∼1 m)과 저층(8 m∼bottom)은 만 안쪽이 고농도 이고 중층(1∼8 m)은 상대적으로 낮다. 이러한 영양염의 분포특성을 바람, 조류, 밀도의 수평경도력 및 잔차류를 고려한 생태계모델을 이용하여 조사하였다. 수치실험은 이들 조건들이 영양염에 각기 어떻게 영향을 미치는 가에 주목하여 실시되었다 조석잔차류를 고려한 경우는 전반적으로 관측값보다 저농도의 분포를 보였고, 바람, 조석잔차류 및 밀도의 수평경도력에 의한 효과를 포함한 경우는 보다 관측값에 근접한 결과를 얻었다 이러한 결과는 통계적 분석 방법에서도 잘 뒤받침된다. 본 연구결과는 하계 진동만에서 영양염의 분포변동에 조류효과 뿐만이 아니라 바람에 의한 취송류 및 밀도의 수평경도력에 의해 발생하는 밀도류의 효과가 매우 중요함을 시사한다.

• 항공우주시스템공학회지
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• 제2권3호
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• pp.24-28
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• 2008

Eddy current are induced when a nonmagnetic, conductive material is moving as the result of being subjected to the magnetic field, or if it is placed in a time-varying magnetic field. These currents circulate in the conductive material and are dissipated, causing a repulsive force between the magnet and conductor. Using this concept, eddy current damping can be used as a form of viscous damping. This paper investigated analytically and experimentally the characteristics of an eddy current damping when a permanent magnet is placed in a conductive tube. The theoretical model of the eddy current damping is developed from electromagnetics and is verified from Maxwell program and experiments. From these comparisons, although predictability is not accurate at high excitation frequencies, the present model can be used to predict damping force at low excitation frequencies. In order to improve the prediction of the characteristics of an eddy current damping, the induced magnetic flux densities have to be considered in following researches.

• 마이크로전자및패키징학회지
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• 제12권1호
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• pp.27-33
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• 2005

The effect of microstructure on alternating current-induced damage in 200 and 300 nm thick polycrystalline sputtered Cu lines on Si substrates has been investigated. Alternating currents were used to generate temperature cycles (with ranges from 100 to $300^{\circ}C$) and thermal strains (with ranges from 0.14 to $0.42\%$) in the Cu lines at a frequency of 10 kHz. Fatigue loading caused the development of severe surface roughness that was localized within individual grains which depends severely on grain orientations.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2007년도 하계종합학술대회 논문집
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• pp.475-476
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• 2007

The stress induced leakage currents will affect data retention in synapse transistors and the stress current, transient current is used to estimate to fundamental limitations on oxide thicknesses. The synapse transistor made by thin silicon oxides has represented the neural states and the manipulation which gaves unipolar weights. The weight value of synapse transistor was caused by the bias conditions. Excitatory state and inhibitory state according to weighted values affected the channel current. The stress induced leakage currents affected excitatory state and inhibitory state.