• 제목/요약/키워드: superposition

검색결과 921건 처리시간 0.025초

펄스 중첩법을 이용한 내부 보이드에서의 부분방전 특성. (Partial Discharge Characteristics at a Internal Void Using a Pulse Superimposing Technique)

  • 강지훈;신두성;황보승;한민구
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 C
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    • pp.1624-1626
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    • 1997
  • In this paper, a new PD measurement technique of pulse superposition method was proposed in order to investigate both PD mechanism and phase related PD patterns. From the experimental results, we could find that the polarity and the phase angle of the superposed pulse take great effects on PD characteristics and these method make it possible to get the physical information which statistical approach can not give. We could conclude that the changes of PD characteristics in the void surrounded by polymers may be attributed to the injection of charge carriers thereby formation of space charge in the surface and/or the bulk of the polymer.

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루프운전 배전선로의 고장계산 방법 (A Fault Calculation Method for Loop Structured Distribution Feeders)

  • 황지희;임성일
    • 전기학회논문지
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    • 제65권10호
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    • pp.1633-1638
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    • 2016
  • Loop system arrangement in the primary distribution system has been increased for higher reliability of power supply to the customer. This paper presents a new fault calculation method for the loop structured unbalanced distribution feeders. Mathematical modeling method of the distribution system and superposition principal based fault calculation procedures are provided. In order to establish feasibility of the proposed method, various case studies have been performed using Matlab power system toolbox.

전기설비용 PET의 절연파괴와 공간전하효과에 관한 연구 (A Study on the Effect of Space Charge and tole Dielectric Breakdown of PEF for Electric Installation)

  • 윤성도;박상현;정학수;서장수;박중순;국상훈
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 1992년도 추계학술발표회논문집
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    • pp.37-40
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    • 1992
  • This paper examined the existance behavior of charged particles by measuring polarity inversion current Thermal Stimulate Current (TSC) and analysed appearance mechanism of polarity inversion current Peak and Also investigated relation between ionic space charge format ion and dielectric breakdown by measuring D.C breakdown impulse breakdown D.C - impulse superposition as a sample of FET. As a result. lie found that dielectric breakdown is likely to happen due to ionic space charge at the transient state when applied polarity inversion voltage and that charged partion of TSE Peak at the high temperature was the same as that of polarity inversion current. Also there was no effect on ionic space charge about the dielectric breakdown in stationary state when applied D.C voltage.

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10/350 ${\mu}s$ 전류파형을 형성하기 위한 대용량 인덕터 특성 (Characteristics of High Energy Inductor to Generate Current Waveform of 10/350 ${\mu}s$)

  • 이태형;조성철;엄주홍;김기복
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2009년도 추계학술대회 논문집
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    • pp.331-334
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    • 2009
  • This paper presents the characteristics of external inductor for impulse current waveform with 10/350 ${\mu}s$ time parameters. Impulse generator was composed with capacitor having large capacitance and low working voltage for the safe of operator and small discharging sound. Parallel R-L-C circuits with crow-bar gaps and superposition method were proposed to make a high current lightning impulse according to IEC 62305-1. The high energy inductor with several taps for fitting half decay time T2 within the tolerance range and experimental data of inductance according to charging voltages were suggested.

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Rheological properties of chitosan solutions

  • Hwang, Jae-Kwan;Shin, Hae-Hun
    • Korea-Australia Rheology Journal
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    • 제12권3_4호
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    • pp.175-179
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    • 2000
  • Rheological properties of chitosan solutions were investigated as a function of polymer concentration. The viscosity curves for chitosan solutions consisted of two distinct viscosity regions, the Newtonian zero-shear viscosity (η$_{0}$) region and the shear rate dependent apparent viscosity (η$_{app}$) region. The shear rate dependence of viscosity was more clearly observed at higher chitosan concentrations. The critical coil overlap parameter (C*〔η〕) was determined to be approximately 3.2 from a plot of zero-shear specific viscosity η$_{sp,0}$ vs coil overlap parameter (C〔η〕), which was lower than C〔η〕4.0 reported for other random coil polysaccharides. It was also found that the slope of η$_{sp,0}$ vs C〔η〕 was 3.9 at concentrated C〔η〕>C*〔η〕domain, while 1.2 at dilute C〔η〕$_{0}$ ${\gamma}$/${\gamma}$$_{0.8}$ relation.ion.n.n.

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Quantum-behaved Electromagnetism-like Mechanism Algorithm for Economic Load Dispatch of Power System

  • Zhisheng, Zhang;Wenjie, Gong;Xiaoyan, Duan
    • Journal of Electrical Engineering and Technology
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    • 제10권4호
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    • pp.1415-1421
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    • 2015
  • This paper presents a new algorithm called Quantum-behaved Electromagnetism-like Mechanism Algorithm which is used to solve economic load dispatch of power system. Electromagnetism-like mechanism algorithm simulates attraction and repulsion mechanism for particles in the electromagnetic field. Every solution is a charged particle, and it move to optimum solution according to certain criteria. Quantum-behaved electromagnetism-like mechanism algorithm merges quantum computing theory with electromagnetism-like mechanism algorithm. Superposition characteristic of quantum methodology can make a single particle present several states, and the characteristic potentially increases population diversity. Probability representation of quantum methodology is to make particle state be presented according to a certain probability. And the quantum rotation gates are used to realize update operation of particles. The algorithm is tested for 13-generator system and 40-generator system, which validates it can effectively solve economic load dispatch problem. Through performance comparison, it is obvious the solution is superior to other optimization algorithm.

구조 지형학적 관점에서 본 현대 건축 공간에 관한 연구 (A Study on Contemporary Architecture Space from a view of structural Geomorphology)

  • 정우석;임종엽
    • 한국실내디자인학회:학술대회논문집
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    • 한국실내디자인학회 2006년도 추계학술발표대회 논문집
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    • pp.219-222
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    • 2006
  • Architecture is builded on the ground and affected environment which include shape of topography and situation. What this study saying is the analysis about the relation between the concept of structural geomorphology and the space modern architecture. As there are many issue about boundary of space and organic architecture, It is important what study about structural geomorphology In paper, we will aware that there are many similarities between architecture and topography. Notion of folded structure in structural geomorphology is connected with continuity or infinity. This is one of many example.

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The Feasibility Study on the Monte Carlo Based RTP Commissioning

  • Kang, Sei-Kwon;Cho, Byung-Chul;Park, Suk-Won;Oh, Do-Hoon;Park, Hee-Chul;Bae, Hoon-Sik
    • 한국의학물리학회:학술대회논문집
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    • 한국의학물리학회 2004년도 제29회 추계학술대회 발표논문집
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    • pp.43-46
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    • 2004
  • The commissioning of a treatment planning system of model-based dose calculation algorithm requires a lot of parameters to be selected to fit measured data, in which process physical insights for the parameters are often forgotten. We present the photon beam commissioning of Pinnacle$^3$ with the help of Monte Carlo (MC) simulation and evaluate the parameters Pinnacle$^3$ demands. Even though the MC calculation produces reasonable values for the commissioning, the thorough physical basis of the Pinnacles$^3$'s commissioning process is needed to use the MC derived parameters directly.

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영상정보 수집 장치용 짐발 구조물의 진동특성해석 (Vibration Characteristic Analysis Of Gimbal Structure in Collection Equipment of Image Information)

  • 이상은;이태원
    • 한국기계가공학회지
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    • 제9권2호
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    • pp.20-25
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    • 2010
  • A camera module is supported by a gimbal structure in collection equipment of image information. During flight, the gimbal system undergoes serious accelerations with wide frequencies. To get the correct images, the camera module must be stably vibrated under these conditions. If natural frequency unfortunately exists in a exciting frequency range, resonance occurs there. Hence, harmonic responses analysis is needed to know correct vibration characteristic of the gimbal system. Finite element analysis was performed to get an acceleration of the gimbal system by mode superposition after extracting mode shapes and natural frequencies. Considering damping ratio of 2%, the reponses of gimbal structure were calculated from excitations with a design frequency band. As results, a maximum acceleration transmissibility, which is the ratio of response to excitation, was obtained and it can be used to design the gimbal structure effectively.

웨이퍼 가공기에서 회전 원판의 동특성에 미치는 불균일 장력의 영향 분석 (Analysis of Non-uniform Tension Effect on Dynamic Characteristics of Spinning Circular Plates in the Wafer Cutting Machine)

  • 임경화
    • 소음진동
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    • 제8권2호
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    • pp.324-330
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    • 1998
  • The forced vibration analysis of the outer-clamped spinnig annular disk with arbitrary in-plane is formulated to investigate the influence of non-uniform tension on the cutting accuracy of wafer cutting machine. The arbitrary in-plan force along the outer edge of an annular plate is expressed as a Fourier series. Galerkin method and modal superposition method are employed to obtain the forced responses under the static force and the impulse force in astationary coordinate. Through qualitative and quantitative analyses, it can be found that forced and impulse responses are sensitive to the non-uniformity of in-plane force, which can bring a bad effect to the accuracy of wafer cutting process. Also, in case of a spinning disk with non-uniform in-plane force, critical speed is required to define in a different way, compared with conventional definition in axi-symmetrical spinning disk.

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