• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 Techno-Fair 및 추계학술대회 논문집 전기물성,응용부문
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• pp.212-213
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• 2007

In case of a line-to-ground fault at transmission lines, a portion of fault current will flow into the earth through the footings of the faulted tower causing electrical potential rise nearby the faulted tower footings. In this situation, any buried pipelines or structures nearby the faulted tower can be exposed to the electrical stress by earth potential rise. Although many research works has been conducted on this phenomena, there has been no clear answer of the required separation distance between tower footings and neary buried pipeline because of its dependancy on the soil electrical charactersics of the concerned area and the faulted system. In this paper, an analytical formula to calculate the requried sepeartion distance from the faulted tower has been derived.

• 대한전자공학회논문지SD
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• 제39권4호
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• pp.10-18
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• 2002

본 논문에서는 IPS모드의 액정 셀에서 전압에 따른 액정 거동을 수치 해석적으로 계산하는 방법을 보고한다. 액정 거동을 해석하기 위해 복잡한 구조에 적용이 용이한 3차원 유한 요소법을 사용하여 액정 셀 내부의 전압 분포와 전계 분포를 계산하였다. 전기 에너지와 액정 분자의 탄성 에너지로 이루어지는 액정 셀 내부의 자유에너지 밀도를 고려하였으며, 에릭슨-레슬리(Ericksen-Leslie) 방정식과 라플라스(Laplace) 방정식을 해석함으로서 액정 셀의 스위칭 특성을 계산하였다. 24㎛×12㎛×4.5㎛ 사이즈의 IPS 모드 액정 셀에 대하여 1,859개의 노드와 8,640개의 사면체 요소를 생성하여 16ms까지 과도 해석하였다. 그 결과, 전극 위 부분을 제외한 영역에서 횡방향의 전계가 형성되었고, 전극 위 영역에서 전경선(disclination)이 발생하는 것을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
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• pp.270-273
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• 2001

In this paper, some of optical current transformers and optical potential transformers for extra high voltage system are introduced. The optical current transformer and optical potential transformer will be adopted in the near future, because of increasing demands of high accuracy and good reliability of current transformer and potential transformer. The application cases of optical current transformers and optical potential transformers are also introduced.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2016년도 제54차 하계학술대회논문집 24권2호
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• pp.261-262
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• 2016

본 논문에서는 계기용변압기(Potential Transformer, PT) 1차권선의 절연내력을 향상시키기 위하여 전위분포가 일정하게 되도록 권선 배치를 최적화하는 프로그램을 작성하여 반복 분석하였다. 우선 기존의 권선 배치에 대한 국소점의 전계분포를 고찰하여 전계의 최대치를 구한 후, 권선 배치를 자동화된 순환 계산형 시뮬레이터를 제작하여 적절한 분포로 교정하고 최초의 기대 함수치를 극소화하는 형상을 반복 추적하는 알고리즘을 이용하였다.

• 대한기계학회논문집A
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• 제32권11호
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• pp.918-923
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• 2008

Since crack detection for laminated composites in-service is effective to improve the structural reliability of laminated composites, it have been tried to detect cracks of laminated composites by various nondestructive methods. An electric potential method is one of the widely used approaches for detection of cracks for carbon fiber composites, since the electric potential method adopts the electric conductive carbon fibers as reinforcements and sensors and the adoption of carbon fibers as sensors does not bring strength reduction induced by embedding sensors into the structures such as optical fibers. However, the application of the electric method is limited only to electrically conductive composite materials. Recently, a piezoelectric method using piezoelectric characteristics of epoxy adhesives has been successfully developed for the adhesive joints because it can monitor continuously the damage of adhesively bonded structures without producing any defects. Polymeric materials for the matrix of composite materials have piezoelectric characteristics similarly to adhesive materials, and the fracture of composite materials should lead to the fracture of polymeric matrix. Therefore, it seems to be valid that the piezoelectric method can be applied to monitoring the damage of composite materials. In this research, therefore, the feasibility study of the damage monitoring for composite materials by piezoelectric method was conducted. Using carbon fiber epoxy composite and glass fiber composite, charge output signals were measured and analyzed during the static and fatigue tests, and the effect of fiber materials on the damage monitoring of composite materials by the piezoelectric method was investigated.

• Advances in nano research
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• 제8권1호
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• pp.69-82
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• 2020

In this study, the free and forced vibration analysis of micro sandwich plate with porous core layer and magneto-electric face sheets based on modified couple stress theory and first order shear deformation theory under simply supported boundary conditions is illustrated. It is noted that the core layer is composed from balsa wood and also piezo magneto-electric facesheets are made of BiTiO₃-CoFe₂O₄. Using Hamilton's principle, the equations of motion for micro sandwich plate are obtained. Also, the Navier's method for simply support boundary condition is used to solve these equations. The effects of applied voltage, magnetic field, length to width ratio, thickness of porous to micro plate thickness ratio, type of porous, coefficient of porous on the frequency ratio are investigated. The numerical results indicate that with increasing of the porous coefficient, the non-dimensional frequency increases. Also, with an increase in the electric potential, the non-dimensional frequency decreases, while and with increasing of the magnetic potential is vice versa.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2000년도 추계학술대회 논문집
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• pp.98-104
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• 2000

The conventional model did not take momentum conservation into consideration when the electron absorbs and emits the photons. II-ray provides momentum conservations on any directions of the entering photons, and also the electrons have radial momentum conservations and fully elastic bouncing between two atoms, in the new atom model. Conventional atom model must be criticized on the following four points. (1) Natural motions between positive and negative entities are not circular motions but linear going and returning ones, for examples sexual motion, tidal motion, day and night etc. Because the radius of hydrogen atom's electron orbit is the order of 10$^{-11}$ m and the radia of the nucleons in the nucleus are the order of 10$^{-14}$ m and then the converging $\pi$-gamma rays to the nucleus have so great circular momentum, the electron can not have a circular motion. We can say without doubt that any elementary mass particle can have only linear motion, because of the $\pi$-rays'hindrances, nearthenucleus. (2) Potential energy generation was neglected when electron changes its orbit from outer one to inner one. The h v is the kinetic energy of the photo-electron. The total energy difference between orbits comprises kinetic and potential energies. (3) The structure of the space must be taken into consideration because the properties of the electron do not change during the transition from outer orbit to inner one even though it produces photon. (4) Total energy conservation law applies to the energy flow between mind and matter because we daily experiences a interconnection between mind and body. Conventional Concept of Electric Field must be extended in the case of the direct and alternating current. Conventional concept is based on coulomb's force while the electric potential in the direct and alternating current is from Gibb's free energy. And also conventional concept has not any consciousness with human being but the latters has a conscious sensibility. The cell emf is from the kinetic energy of the open $\pi$-rays flow through the conducting wire. The electric potential in alternating current is from that the trans-orbital moving of the induced change of magnetic field in the wire produces flows of open $\pi$-rays, which push the rotating electrons on the orbital and then make the current flow. Human consciousness can induce a resonance with the sensibility of the open $\pi$-rays in the electric measuring equipment. Specially treated acupunctures with Nasucon is for sending an acupunctural effect from one place to another via space by someone's will power.

• 스마트미디어저널
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• 제6권2호
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• pp.26-32
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• 2017

본 논문에서는 지구전기장 왜란신호를 전위차로 변환하는 EPIC(Electric Potential Integrated Circuit) 센서를 이용한 NUI(Natural User Interface) 기술의 요소기술인 신호검출 전자회로를 기반으로 LED 조명을 제어하는 시스템을 구현하였다. 기존에는 CIB 개발 장비를 통해서만 제한적인 형태로 이용 가능했던 신호를 모든 EPIC 센서 각각의 신호를 추출할 수 있도록 개발된 신호검출 전자회로를 이용하였다. 이렇게 추출한 신호는 이후 손동작 인식프로세스에서 특징추출 등의 과정에서 더 많은 자유도와 성능개선 효과를 보여준다. 설계되어 제작된 회로의 실제 응용시스템으로서 적용성을 검증하기 위하여 4개의 손동작으로 LED 조명의 on/off 와 밝기를 조정할 수 있는 시스템을 설계하였다. 기존의 EPIC 센서를 이용하여 명령체계를 구축하고 인터페이스 제어신호를 이용하여 보다 빠른 패턴인식 처리 속도를 얻을 수 있었다.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2001년도 춘계학술대회 논문집
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• pp.10-14
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• 2001

Physical chemistry states that electric potential is due to Gibb's free energy from chemical reaction of the electric cell. However we have not the electromagnetic meaning of Gibb's free energy. the free energy is discovered to be a kinetic energy part of the rotating electromagnetic wave ($\pi$-ray), which is different from conventional Coulomb attraction energy and can anticipate that there is a current difference between before and after the electric load. This paper manipulates the relationship between $\pi$-rays (Gibb's free energy) and electrolysis, cell reaction and brown gas reaction.

• Journal of the Korean Wood Science and Technology
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• 제18권1호
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• pp.24-30
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• 1990

This study was attempted to propose a method evaluating fixation of active ingredients in Copper-Chromium-Arsenic preservatives treatment. Fixated amount of active ingredients on wood was obtained by measuring the density of surface electric charge based on $\varsigma$ potential. Data accumulated from density of surface electric charge showed that the fixated amount of preservatives on wood increased linearly as concentration of treating solution increaced, which indicatied quantitative reactions in fixation of preservatives.