• Title/Summary/Keyword: IS-801

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A study of Heat Transfer Enhancement by Temperature Driven Marangoni Convection (온도차 마랑고니 대류에 의한 열전달 촉진에 관한 연구)

  • 김종윤;이동호;박종화;최국광
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.15 no.10
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    • pp.795-801
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    • 2003
  • The primary object of this study is to obtain a basic knowledge of heat transfer enhancement mechanism as affected by temperature driven Marangoni convection. Experiments is achieved to visualize the enhanced heat transfer phenomena by the effect of Marangoni convection through the laser holographic interferometry. Also Nusselt Number is introduced for the relation of Marangoni Number.

Modulation in NMDA and $GABA_A$ Receptor Expression after Cerebroventricular Infusion of Ginsenosides

  • Oh Seikwan;Kim Hack-Seang
    • Proceedings of the Ginseng society Conference
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    • 2002.10a
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    • pp.96-112
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    • 2002
  • In the present study, we have investigated the effects of centrally administered ginsenoside Rc or Rgl on the modulation of NMDA receptor and $GABA_A$ receptor binding in rat brain. The NMDA receptor binding was analyzed by quantitative autoradiography using $[^3H]MK-801$ binding, and $GABA_A$ receptor bindings were analyzed by using $[^3H]muscimol\;and\;[^3H]flunitrazepam$ in rat brain slices. Rats were infused with ginsenoside Rc or Rg1 ($10\;{\mu}g/10{\mu}l/hr$, i.c.v.) for 7 days, through pre-implanted cannula by osmotic minipumps (Alzet, model 2ML), The levels of $[^3H]MK-801$ binding were highly decreased in part of cortex and cingulated by ginsenoside Rc and Rgl. The levels of $[^3H]muscimol$ binding were strongly elevated in almost all regions of frontal cortex by the treatment of ginseoside Rc but decreased by ginsenoside Rg 1. However, the $[^3H]flunitrazepam$ binding was not modulated by ginsenoside Rc or ginsenoside Rgl infusion. These results suggest that prolonged infusion of ginsenoside could differentially modulate $[^3H]MK-801\;and\;[^3H]muscimol$ binding in a region-specific manner. Also, we investigated the influence of centrally administered ginsenoside on the regulation of mRNA levels of the family of NMDA receptor subtypes (NR1, NR2A, NR2B, NR2C) by in situ hybridization histochemistry in the rat brain. The level of NR1 mRNA is significantly increased in temporal cortex, caudate putamen, hippocampus, and granule layer of cerebellum in Rgl-infused rats as compared to control group. The level of NR2A mRNA is elevated in the frontal cortex. In contrast, it was decreased in CAI area of hippocampus in Rgl-infused rats. However, there was no significant change of NR1 and NR2A mRNA levels in Rc-infused rats. The level of NR2B mRNA is elevated in cortex, caudate putamen, and thalamus in both Rc- and Rg-infused rats. In contrast, NR2B level is decreased in CA3 in Rgl-infused rats. The level of NR2C mRNA is increased in the granule layer of cerebellum in only Rg1 but not Rc infused rats. These results show that structure difference of ginsenoside may diversely affect the modulation of expression of NMDA receptor subunit mRNA after infusion into cerebroventricle in rats.

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Application and System Establishment on Quality Control of Flowing Concrete (유동화 콘크리트의 현장적용과 품질관리 시스템 구축)

  • 김규용;길배수;한장현;주지현;박선규;한승구;조성기;김무한
    • Proceedings of the Korea Concrete Institute Conference
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    • 1999.10a
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    • pp.801-804
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    • 1999
  • The interest in workability and quality control of concrete is increasing as to improve quality of concrete structure according to industrialization. Therefore, it is the aim of this study to evaluate the quality of flowing concrete and systematize quality control by analyzing the data of the quality control of concrete through a basic quality control system for improvement of the concrete in pumping flowing concrete for construction industy.

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An expert system for controlling CIM operation (CIM 공장의 운용 통제 전문가 시스템)

  • 김성식;이태진;김재만
    • 제어로봇시스템학회:학술대회논문집
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    • 1992.10a
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    • pp.801-805
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    • 1992
  • Due to the inherent complexity in the CIM operation, achieving the triple, meeting duedates, maximizing machine utilization, and maximizing system throughput simultaneously is practically impossible. Targeting the small-to-medium size industries of Korea, we propose an exrert system that 'provides a good and practical solution to the CIM operation problems. Heavy consideration has given to the real-time and dynamic nature of CIM in the development process of the system. The system is under testing stage at KU-FMS, model CIM plant.

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SLOW VISCOUS FLOW PAST A CAVITY WITH INFINITE DEPTH

  • Kim, D.W;Kim, S.B;Chu, J.H
    • Journal of applied mathematics & informatics
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    • v.7 no.3
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    • pp.801-812
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    • 2000
  • Two-dimensional slow viscous flow on infinite half-plane past a perpendicular infinite cavity is considered on the basis of the Stokes approximation. Using complex representation of the two-dimensional Stokes flow, the problem is reduced to solving a set of Fredholm integral equations of the second kind. The streamlines and the pressure and vorticity distribution on the wall are numerically determined.

RESEARCH OF AN ACTIVE FILTER BASED BALANCED POWER SUPPLY SYSTEM FOR RAIL WAY TRACTION

  • Zeng, Guohong;Hao, Rongtai
    • Proceedings of the KIPE Conference
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    • 1998.10a
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    • pp.797-801
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    • 1998
  • This paper presents a balanced 3/1 supply scheme for electric railway. By employing an active filter, the current of the three-phrase delivery system is balanced while the load is single phrase, which makes it possible for the traction system to behave like a pure-resistance load, with unity power factor and no harmonics. Simulation results are present to verify the scheme's topology and control strategies.

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On the Signal Power Normalization Approach to the Escalator Adaptive filter Algorithms

  • Kim Nam-Yong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.8C
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    • pp.801-805
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    • 2006
  • A normalization approach to coefficient adaptation in the escalator(ESC) filter structure that conventionally employs least mean square(LMS) algorithm is introduced. Using Taylor's expansion of the local error signal, a normalized form of the ESC-LMS algorithm is derived. Compared with the computational complexity of the conventional ESC-LMS algorithm employs input power estimation for time-varying convergence coefficient using a single-pole low-pass filter, the computational complexity of the proposed method can be reduced by 50% without performance degradation.

Design Considerations on Partition of SOP, CMOS and PCB technologies for Mobile Display System Implementation

  • Lee, Seung-Yong;You, Jae-Hee
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08a
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    • pp.798-801
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    • 2007
  • For lower power and smaller size with higher image quality, it is desirable to have more units integrated on a display panel. It needs careful design considerations in selecting CMOS, SOP or PCB. An experimental display system is designed and power and delay considering chip area, data rates and bus width are analyzed for all technology combinations to obtain optimum design methodologies.

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Character Extraction from the Hangeul Document Image Represented by a Quadtree (쿼드트리로 표현된 한글 문서 영상에서의 문자 추출)

  • 백은경;조동섭
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.41 no.7
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    • pp.793-801
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    • 1992
  • This paper proposes a method of extracting connected strokes and characters in a Hangeul document image represented by a quadtree. Connected strokes are extracted by examining adjacency for each node of a black region to the side of east and south. Then, each character is extracted by the sizes and the relations of connected strokes. This is done by iterative vertical and horizontal manipulation. The result shows all characters are extracted in the same sequence as that of context with space and time efficiency.

IDE-LEACH Protocol for Trust and Energy Efficient Operation of WSN Environment (WSN의 에너지 효율적 운영을 위한 신뢰성이 보장된 IDE-LEACH 프로토콜)

  • Cho, Young-Bok;Woo, Seng-Hee;Lee, Sang-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38B no.10
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    • pp.801-807
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    • 2013
  • WSN consists of hundreds to thousands of sensor nodes. In order to solve the problem of energy consumption imbalance cluster head is reelected in every round, while node authentication scheme is utilized for secure communication. However, re-clustering increases the overhead of sensor nodes and during the node authentication phase the frequent AREQ/AREP message exchange also increases the overhead. Therefore, a secure and energy efficient protocol, by which overhead of sensor nodes is reduced and long time communication is achieved, is required for wireless sensor network. In this paper, an energy efficient and reliable IDE-LEACH protocol for WSN is proposed. The proposed protocol is prolongs networks lifetime about average 20% compared to the LEACH-based protocols and all attending nodes in communication form BS authentication consisted of trusted nodes.