• 제목/요약/키워드: E-J characteristic

검색결과 177건 처리시간 0.023초

BLDC 모터 구동을 위한 신경회로망 PI파라미터 자기 동조 시뮬레이터 (Neural Network PI Parameters Self-tuning Simulator for BLDC Motor operation)

  • 배은경;권중동;김태우;김대균;전지용;이승환;이훈구;김용주;한경희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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    • pp.759-760
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    • 2006
  • In this paper proposed to Neural network PI self-tuning direct controller using Error back propagation algorithm. Proposed controller applies to speed controller and current controller. Also, this built up the interface environment to drive it simply and exactly in any kind of reference, environment fluent and parameter transaction of BLDC motor. Neural network PI self-tuning simulator using Visual C++ and Matlab Simulation is organized to construct this environment. Built-u-p interface has it's own purpose that even the user who don't have the accurate knowledge of neural network can embody operation characteristic rapidly and easily.

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Human Apolipoprotein E2 Transgenic Mice Show Lipid Accumulation in Retinal Pigment Epithelium and Altered Expression of VEGF and bFGF in the Eyes

  • Lee, Sung-Joon;Kim, Jeong-Hun;Kim, Jin-Hyoung;Chung, Mi-Ja;Wen, Qingcheng;Chung, Hum;Kim, Kyu-Won;Yu, Young-Suk
    • Journal of Microbiology and Biotechnology
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    • 제17권6호
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    • pp.1024-1030
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    • 2007
  • We investigated the human apolipoprotein E2 (apoE2) transgenic mouse as an animal model system for age-related macular degeneration (AMD). Transgenic mice expressing human apoE2 and C57BL/6J mice were fed normal chow or a high-fat diet for 4 weeks. Eyes were collected from the mice and lipid deposits in retinal pigment epithelium (RPE) were assessed using electron microscopy. The expressions of apoE, vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and pigment-epithelium derived factor (PEDF), which are molecular markers for angiogenesis, were assessed with immunohistochemistry. Eyes from apoE2 mice, regardless of diet, contained lipid accumulation in RPE under electron microscopy, whereas control C57BL/6J eyes did not. Lipid accumulation was found predominantly in the RPE and the Bruch's membrane and increased in the eyes of apoE2 mice after one month of a high-fat diet ($8{\pm}2\;per\;50{\mu}m^2$ for normal chow and $11{\pm}2\;per\;50\;{\mu}m^2,\;p<0.05)$. ApoE expression was similar in the apoE2 and control mice; however, VEGF and bFGF were overexpressed in the retinal pigment epithelium of apoE2 eyes compared with control eyes, and PEDF expression was slightly decreased. These expression patterns of VEGF, bFGF, and PEDF suggest angiogenesis is progressing in apoE2 eyes. In conclusion, the eyes of apoE2 mice develop typical lipid accumulations, a common characteristic of AMD, making them a suitable animal model for AMD. The expression profile of VEGF and bFGF on the retinal pigment epithelium suggests that apoE2 may induce neovascularization by altering angiogenic cytokines.

석조문화재의 석재공급지에 관한 연구 -익산 지역에 대한 지형학적 및 암석학적 접근- (Study on the Source Area of the Stones from Stone-cultural Properties -Geomorphological and Petrological Approach for the Iksan Area-)

  • 조기만;좌용주
    • 암석학회지
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    • 제14권1호
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    • pp.24-37
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    • 2005
  • 본 연구에서는 익산의 미륵산 일대의 화강암 지형경관에 대한 지형학적 및 지질학적 특성을 파악하고, 더불어 미륵사지 서탑에 사용된 석재의 공급지를 추정하였다. 절리는 익산 지역에서 가장 뚜렷한 지형학적 및 지질학적 구조이며, J1 절리의 방향은 N71°E∼EW이고 J2 절리의 방향은 N20°W∼N20°E의 범위를 나타낸다. 절리의 형태를 세분할 때 연구지역에서는 cross형의 절리가 우세하며 또한 linear형의 수직절리도 관찰된다. 지형적 특징으로 토어와 핵석도 관찰되는데, 토어를 이루는 핵석들은 2∼3m의 길이에 2∼3m 또는 5m 이상의 높이를 가진다. 그들의 경도는 주로 hammer bounce에 속한다. 미륵산 화강암에서 나타나는 토어는 tower형과 castle형이 우세하다. 한편 타포니와 나마 등과 같은 지형적 특징도 나타난다. 미륵사지 서탑의 석재와 인근 미륵산 화강암의 암석기재적 및 지구화학적 특징들을 비교할 때, 이 두 암석들은 매우 유사함이 지적되어 미륵산이 석재의 공급지일 가능성이 제기된다. 미륵산에서는 과거 채석의 흔적이 다수 발견되기도 한다.

Single-Electron Logic Cells and SET/FET Hybrid Integrated Circuits

  • Kim, S.J.;Lee, C.K.;Lee, J.U.;Choi, S.J.;Hwang, J.H.;Lee, S.E.;Choi, J.B.;Park, K.S.;Lee, W.H.;Paik, I.B.;Kang, J.S.
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제6권1호
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    • pp.52-58
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    • 2006
  • Single-electron transistor (SET)-based logic cells and SET/FET hybrid integrated circuits have been fabricated on SOI chips. The input-output voltage transfer characteristic of the SET-based complementary logic cell shows an inverting behavior where the output voltage gain is estimated to be about 1.2 at 4.2K. The SET/FET output driver, consisting of one SET and three FETs, yields a high voltage gain of 13 and power amplification with a wide-range output window for driving next circuit. Finally, the SET/FET literal gate for a multi-valued logic cell, comprising of an SET, an FET and a constant-current load, displays a periodic voltage output of high/low level multiple switching with a swing as high as 200mV. The multiple switching functionality of all the fabricated logic circuits could be enhanced by utilizing a side gate incorporated to each SET component to enable the phase control of Coulomb oscillations, which is one of the unique characteristics of the SET-based logic circuits.

Gaussian Mixture Model 기반 전완 근전도 패턴 분류 알고리즘 (A Gaussian Mixture Model Based Pattern Classification Algorithm of Forearm Electromyogram)

  • 송영록;김서준;정의철;이상민
    • 재활복지공학회논문지
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    • 제5권1호
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    • pp.95-101
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    • 2011
  • 본 논문에서는 의수환자의 일상생활을 고려한 1-자유도 동작을 손을 쥐고 폄으로 정의하고, 두 동작에 대한 근전도 패턴 분류를 위한 가우시안 혼합 모델 기반의 근전도 패턴 분류 알고리즘을 제안한다. 근전도 패턴 분류 알고리즘의 핵심이 되는 근전도 신호의 특징점 추출을 위하여 근전 신호의 진폭 특성을 고려하는 절대차분평균치(DAMV)와 평균절대값(MAV)을 사용한다. 또한 동작에 대한 근전 신호의 진폭 특성을 보다 명확히 구분하기 위하여 D_DAMV와 D_MAV를 제안한다. 본 논문에서는 4명의 성인남성을 대상으로 실험을 실시하였고, 두 동작에 대한 근전도 패턴의 정확한 분류 여부를 확인하였다.

Mindlin판 특성함수를 이용한 직사각형 후판의 진동해석 (Vibration Analysis of Rectangular Thick Plates Using Mindlin Plate Characteristic Functions)

  • 이종문;김극천
    • 대한조선학회논문집
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    • 제33권2호
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    • pp.85-95
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    • 1996
  • 직사각형 Mindlin판 유추계의 고유진동 및 동적응답의 해석에 대하여 종래의 방법들 보다 정확도 및 계산효율을 향상시킬 수 있는 방법을 추구하였다. Mindlin 판이론에 입각하여 탄성구속경계조건에 대해 정식화 하고, Timoshenko 보함수로부터 시작하는 Kantorovich 방법을 원용하여 Mindlin 판특성함수를 도출했다. 이 Mindlin판 특성함수에 기초하여 등방성후판 및 직교이방성후판에 대해서 반복적 Kantorovich 방법에 의해 고유해를 구하는 방법을 제시했다. 이 방법은 정확도 및 계산효율면에서 종래의 다른 근사해법보다 그 우월성이 인정되며, 특히 중복고유치를 갖는 경우 명확한 고유치 및 고유모드를 얻을 수 있다. 또 모드해석방법에 의한 동적응답계산에 있어서도 보다 더 정확한 결과를 얻을 수 있다.

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최적화 기법에 의한 발전시뮬레이션 방법론의 개발 및 전원확충계획 문제에의 적용 (The Development of Production Simulation Methodology by Optimization Technique and It's Application to Utility Expansion Planning)

  • 송길영;오광해;김용하;차준민
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 B
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    • pp.793-796
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    • 1996
  • This study proposes a new algorithm which performs a production simulation under various constraints and maintains computational efficiency. In order to consider the environmental and operational constraints, the proposed algorithm is based on optimization techniques formulated in LP form In the algorithm, "system characteristic constraints" reflect the system characteristics such as LDC shape, unit loading order and forced outage rate. By using the concept of Energy Invariance Property and two operational rules i.e. Compliance Rule for Emission Constraint, Compliance Rule for Limited Energy of Individual Unit, the number of system characteristic constraints is appreciably reduced. As a solution method of the optimization problem, the author uses Karmarkar's method which performs effectively in solving large scale LP problem. The efficiency of production simulation is meaningful when it is effectively used in power system planning. With the proposed production simulation algorithm, an optimal expansion planning model which can cope with operational constraints, environmental restriction, and various uncertainties is developed. This expansion planning model is applied to the long range planning schemes by WASP, and determines an optimal expansion scheme which considers the effect of supply interruption, load forecasting errors, multistates of unit operation, plural limited energy plants etc.

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환경 인자에 따른 FRP의 표면화특성에 관한 연구 (A Study on the Surface Degradation Properties of Glass Fiber Reinforced Plastics by Environmental Factors)

  • 임경범;정기현;이백수;황명환;박종관;박종국;정의남;이덕출
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 D
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    • pp.1627-1629
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    • 1999
  • In order to analysis the degradation process of epoxy/glass fiber for outdoor condition, FRP laminate was exposed to high temperature and water. Then the degradation process was evaluated by comparing contact angle, surface potential decay, and surface resistivity. For the change of wettability, the contact angle of thermal-treated specimen with the high temperature of $200^{\circ}C$ increased. But that of water-treated specimen decreased. The characteristic of surface potential decay shows the tendency of the remarkable decrease on water-treated specimens, but no difference on thermal-treated specimen compared with untreated one. Also, for the surface resistivity, it shows the same trend compared with the change of contact angle.

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Humanized Milk제조에 관한 연구 제 1 보 모유화분유 조제와 외국산제품과의 비교 (Development of the Humanized Milk Part 1. Relative Nutritional Value, Preparation Chemical Composition of Humanized milk and Comparison of Commercial Products)

  • 유영진;이태녕;김승한;한덕봉;고정배;정충일
    • 한국식품과학회지
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    • 제6권2호
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    • pp.91-97
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    • 1974
  • This paper was developed for production of the humanized milk, comprising similarly to the composition and characteristic of human milk. Humanized milk of superior quality can be made directly from the fresh raw milk mixed vegetable oil, corn syrup, whey powder, ${\beta}-lactose$, sugar, vitamin, ${\beta}-carotene$ and minerals showing formulation of the humanized milk at table 2. The improving effects of adding vegetable oil and corn syrup are both more reformed the chemical and physical properties of humanized milk. The former enhanced the essential fatty acid and energy source in this product, the latter has the most solving function in water and induced amount of emulsion and stabilizer. The products contain about 13% protein, 23% fat, 58.3% carbohydrate, 2% ash and ensue reasonably balance of essential amino acid, poly-unsaturated fatty acid for the requirement of infants and controlled component of the humanized milk such as human milk.

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PWM 컨버터를 이용한 계통연계형 태양광발전 시스템 (A Utility Interactive Photovoltaic Generation System using PWM Converter)

  • 김대균;정정훈;정춘병;김성남;이승환;강승욱;오봉환;이훈구;김용주;한경희
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2004년도 전력전자학술대회 논문집(1)
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    • pp.133-136
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    • 2004
  • Since the residential load is an AC load and the output of solar cell is a DC power, the photovoltaic system needs the DC/AC converter to utilize solar cell. In case of driving to interact with utility line, in order to operate at unity power factor, converter must provide the sinusoidal wave current and voltage with same phase of utility line. Since output of solar cell is greatly fluctuated by insolation, it is necessary that the operation of solar cell output in the range of the vicinity of maximum power point. In this paper, DC/AC converter is three phase PWM converter with smoothing reactor. And then, feedforward control used to obtain a superior characteristic for current control and digital PLL circuit used to detect the phase of utility line.

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