• 제목/요약/키워드: Lee Jang Ga

검색결과 275건 처리시간 0.028초

유전자 알고리즘을 이용한 퍼지 제어규칙의 최적동조 (Optimal Auto-tuning of Fuzzy control rules by means of Genetic Algorithm)

  • 김중영;이대근;오성권;장성환
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 추계학술대회 논문집 학회본부 B
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    • pp.588-590
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    • 1999
  • In this paper the design method of a fuzzy logic controller with a genetic algorithm is proposed. Fuzzy logic controller is based on linguistic descriptions(in the form of fuzzy IF-THEN rules) from human experts. The auto-tuning method is presented to automatically improve the output performance of controller utilizing the genetic algorithm. The GA algorithm estimates automatically the optimal values of scaling factors and membership function parameters of fuzzy control rules. Controllers are applied to the processes with time-delay and the DC servo motor. Computer simulations are conducted at the step input and the output performances are evaluated in the ITAE.

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시간영역유한차분법을 이용한 극초고주파용 CPW의 최적화 설계 (Optimum Design of EHF CPW using FDTD)

  • 장인범;이준웅
    • 한국전기전자재료학회논문지
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    • 제18권12호
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    • pp.1129-1132
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    • 2005
  • The purpose of this reserch is to establish the new design technology for microwave Coplanar structure. The components in microwave circuit are classified to transmission devices, EM devices, and quasi-TEM devices. After design of these devices, we analyzed these CPWs electromagnetically using FDTD method, and suggested optimum CPW structure. In oder to realize a CPW module up to 30 GHz-100 GHz band, we research on a technology of 3-dimensional microwave CPW, and GaAs substrate with Si layer for ohmic loss. As a result this research, we suppressed the leakage, resonance, coupling, and radiation of CPW EMI, and improved resonance quality of CPW.

Multipoint Process Monitoring System Based on a Near Infrared Ray(NIR) Acousto-Optic Tunable Filter(AOTF)

  • You, Jang-Woo;Kim, Daesuk;Kim, Soohyun;Kong, Hong-Jin;Lee, Yunwoo;Kwak, Yoon-Keun
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.105.4-105
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    • 2001
  • This paper describes a newly designed multipoint process monitoring system based on a NIR acousto-optic tunable filter. The NIR multipoint process monitoring system consists of a NIR AOTF device for wavelength selection, an InGaAs array sensor, and a specially designed iin-line type of optical fiber probe. Unlike a FTS(Fourier Transform Spectrometry) or grating based monitoring system, an AOTF has no moving parts, and it can be rapidly tuned to any wavelength in its operating range within microseconds. Thus, the AOTF is advantageous in terms of faster spectral imaging capability and rigidity required for industrial monitoring environment. In the current feasibility evaluation, an enhanced optical fiber probe with 3 monitoring points was used. However, ...

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송전손실 재분배를 고려한 유전 알고리즘 기반의 무효전력 최적배분 (GA-Based ORPD considering Transmission Losses Re-Distribution)

  • 채명석;이명환;김병섭;신중린
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 추계학술대회 논문집 학회본부 A
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    • pp.190-192
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    • 1999
  • This paper presents an algorithm for optimal reactive power dispatch problem based on genetic algorithm. Optimal reactive power dispatch is particularized to the minimization of transmission line losses by suitable selection of generator reactive power outputs and transformer tap settings. To attain for the objective, in this paper, loss re-distribution algorithm(LRDA) is applied to ORPD. The proposed method has been evaluated on the IEEE 30 bus system. Results of the application of the method are compared with a simple genetic algorithm.

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The current status of fish biodiversity around the DMZ and CCL area

  • Cho, Ga-Ik;Jang, Min-Ho;Lee, Chan-Woo;Joo, Gea-Jae
    • 한국어업기술학회:학술대회논문집
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    • 한국어업기술학회 2003년도 춘계 수산관련학회 공동학술대회발표요지집
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    • pp.351-352
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    • 2003
  • The demilitarized zone (DMZ) covered about 1, 528 $\textrm{km}^2$ (length, 248 km; width, about 4 km), and the civilian control line (CCL) was established around the DMZ after the Korean War. The international organizations (UNESCO and IUCN) showed a continued interests on the biodiversity of the DMZ area, because of relatively well preserved environment and lack of anthropogenic disturbances other than agricultural practice (KFRI, 2000). (omitted)

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High performance organic gate dielectrics for solution processible organic and inorganic thin-film transitors

  • 가재원;장광석;이미혜
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2012년도 춘계학술발표대회
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    • pp.64.1-64.1
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    • 2012
  • Next generation displays such as high performance LCD, AMOLED, flexible display and transparent display require specific TFT back-planes. For high performance TFT back-planes, low temperature poly silicon (LTPS), and metal-oxide semiconductors are studied. Flexible TFT backplanes require low temperature processible organic semiconductors. Not only development of active semiconducting materials but also design and synthesis of semiconductor corresponding gate dielectric materials are important issues in those display back-planes. In this study, we investigate the high heat resistant polymeric gate dielectric materials for organic TFT and inorganic TFT with good insulating properties and processing chemical resistance. We also controlled and optimized surface energy and morphology of gate dielectric layers for direct printing process with solution processible organic and inorganic semiconductors.

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합금화 용융아연 도금강판의 가공시 손상모델을 이용한 도금층 파우더링에 관한 유한요소 해석 (Finite Element Analysis of Powdering of Hot-dip Galvannenled Steel using Damage Model)

  • 김동욱;김성일;장윤찬;이영석
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2007년도 추계학술대회 논문집
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    • pp.215-222
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    • 2007
  • Coating of Hot-dip galvannealed steel consists of various Fe-Zn intermetallic compounds. Since the coating is hard and there for is very brittle, the surface of steel sheet is easy to be ruptured during second manufacturing processing. This is called as powdering. In addition, forming equipment might be polluted with debris by powdering. Therefore, various research have been carried out to prohibit powdering fur improving the quality of GA steel. This paper carried out finite element analysis combined with damage model which simulate the failure of local layer of hot-dip galvannealed steel surface during v-bending test. Since the mechanical property of intermetallic compound was unknown exactly, we used the properties calculated from measurements. The specimen was divided into substrate, coating layer and interface layer. Local failure at coating layer or interface layer was simulated when elemental strain reached a prescribed strain.

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Ursane-Type Triterpenoids from the Aerial Parts of Potentilla discolor

  • Jang, Dae-Sik;Kim, Jong-Min;Lee, Ga-Young;Kim, Joo-Hwan;Kim, Jin-Sook
    • Journal of Applied Biological Chemistry
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    • 제49권2호
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    • pp.48-50
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    • 2006
  • Four ursane-type triterpenoids, ursolic acid (1), 23-hydroxyursolic acid (2), corosolic acid (3), and tormentic acid (4), and a phytosterol, ${\beta}-sitosterol-3-O-{\beta}-D-glucoside$, were isolated from an EtOAcsoluble extract of the aerial parts of Potentilla discolor. The structures of 1-4 were identified by spectroscopic methods, particularly by extensive NMR studies. This is the first report on the isolation of compounds 1-4 from this plant.

Neuroimaging-Based Deep Learning in Autism Spectrum Disorder and Attention-Deficit/Hyperactivity Disorder

  • Song, Jae-Won;Yoon, Na-Rae;Jang, Soo-Min;Lee, Ga-Young;Kim, Bung-Nyun
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • 제31권3호
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    • pp.97-104
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    • 2020
  • Deep learning (DL) is a kind of machine learning technique that uses artificial intelligence to identify the characteristics of given data and efficiently analyze large amounts of information to perform tasks such as classification and prediction. In the field of neuroimaging of neurodevelopmental disorders, various biomarkers for diagnosis, classification, prognosis prediction, and treatment response prediction have been examined; however, they have not been efficiently combined to produce meaningful results. DL can be applied to overcome these limitations and produce clinically helpful results. Here, we review studies that combine neurodevelopmental disorder neuroimaging and DL techniques to explore the strengths, limitations, and future directions of this research area.

전력반도체 소자에 따른 All Metal Induction Cooktop 설계 및 손실분석 (Design and Analysis of All-Metal Induction Cooktop for Power Semiconductor Devices)

  • 심동현;권만재;장은수;박상민;이병국
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2019년도 추계학술대회
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    • pp.160-161
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    • 2019
  • 본 논문에서는 Si-MOSFET 및 GaN-HEMT 기반 All Metal Induction Cooktop의 고효율 동작을 위한 공진네트워크 설계 및 운전주파수영역을 제시한다. 이를 위해 워킹 코일과 용기의 등가 파라미터를 바탕으로 동작 주파수에 따른 공진 네트워크를 각각 설계한다. 또한 시뮬레이션 및 수학적 계산을 통해 설계된 시스템의 주파수 조건 별 손실 비교를 통해 각 스위칭 소자에 따른 적합한 공진네트워크 설계방안을 제시한다.

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