• Title/Summary/Keyword: 호재

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Development of the Pre-Release Simulation System Using Generic Agricultural System Simulator(GASS) (범용적 농업 시스템 시뮬레이터(GASS)를 이용한 예비방류 모의 시스템의 개발)

  • Song, Sang-Ho;Lee, Jeong-Jae;Kim, Han-Joong;Yi, Ho-Jae
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2003.10a
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    • pp.539-542
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    • 2003
  • In South Korea, flooding is controlled with large or small reservoirs scattered spatially over the territory. Because recent unexpected hard-rain events requires more flood control capacities, the pre-release system is considered with the most economical alternative. In this case time and volume of discharge should be determined by the simulation. But, existing pre-release simulation system has the problem of specificity. Therefore, GASS is considered to estimate the pre-release time and volume with different configurations of pre-release system. This paper shows that pre-release simulation system could be constructed with arranging GASAtmosphere, GASWatershed, Reservoir, Gate components using GASS. It is also shows that GASS could be used as a foundation for constructing pre-release simulation system that is easy to use and is flexible to reflect the changing configurations of reservoir systems.

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Static Output-Feedback-Based Robust Fault Tolerant Controller Design (정적 출력궤환 기반 강인 고장포용 제어기 설계)

  • Jee, Sung Chul;Moon, Ji Hyun;Lee, Ho Jae
    • Journal of Institute of Control, Robotics and Systems
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    • v.19 no.7
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    • pp.587-591
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    • 2013
  • This paper addresses the robust fault tolerant controller design problems of static output systems with disturbance. The fault is expressed by the abrupt chattering of system parameters. The design conditions are derived in terms of linear matrix inequalities and linear matrix equalities. An illustrative example is provided to verify performances of the proposed controller.

An experimental study on the Bonding Strength and Strain of Coating Material according to Temperature Condition (온도조건에 따른 표면보호재의 부착강도 특성 및 변형 특성에 관한 실험적 연구)

  • Bae, Jun-Young;Kwan, In-Pyo;Kim, Kyung-Deok;Kang, Suk-Pyo;Kawk, Ju-Ho;Kim, Jung-Hwan
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.05b
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    • pp.293-296
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    • 2006
  • Normally, using coating material could result in different performance according to the various changes of environments or operation conditions. For these reasons, there are decreasing tendency for the durability, beauty and scenery of structures as the separation or exfoliation occurred after operation. Especially we must find out not only bond strength characteristics of coating material under temperature conditions but also bond strength reduction under heating-cooling repeat test because Korea has four distinct seasons. In this paper, the deformation and bond strength characteristics of coating material have been investigated. and we suggest some preliminary data of coating material for its best performance under various temperature condition.

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An Experimental Study on the Properties of Surface Protection Materials to Durability of Concrete (콘크리트 내구성 향상을 위한 표면보호재의 특성에 관한 실험적 연구)

  • Lee, Jeoung-Yun;Cho, Byoung-Young;Kim, Young-Geun;Oh, Sang-Keun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.05b
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    • pp.173-176
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    • 2006
  • Concrete has been considered as a semi-permanent structural material, because its excellent durability. But concrete durability is affected by carbon dioxide, chloride, water, etc. This study is about surface protection materials-one materials is silane type and the other silicate type for the promoting of concrete durability. As a results, Silane type could protect affection of chloride(Cl-), water(H2O), carbon dioxide(CO2). Also silicate type could improve the abrasion of concrete.

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The corrosion behaviour of steel in high alumina cement concrete (알루미나 시멘트 콘크리트의 철근 부식 저항성)

  • Lee, Ho-Jae;Kim, Jae-Hwan;Ann, Ki-Yong;Song, Ha-Won
    • Proceedings of the Korea Concrete Institute Conference
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    • 2009.05a
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    • pp.289-290
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    • 2009
  • In this study, the resistance of calcium aluminate cement (CAC) against chloride-induced corrosion was assessed by testing for the strength, chloride transport, and corrosion behaviour. The study found that the CAC concrete had better performance than ordinary Portalnd cement(OPC) in resisting the corrosion of steel.

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Fuzzy Controller by Using Digital Redesign (디지털 재설계를 이용한 퍼지제어기)

  • Lee, Ho-Jae;Joo, Young-Hoon;Park, Jin-Bae
    • Proceedings of the KIEE Conference
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    • 1999.07b
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    • pp.630-632
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    • 1999
  • In this paper, we develop intelligent digitally redesigned PAM and PWM fuzzy controllers for nonlinear systems. Takagi-Sugeno fuzzy model is used to model the nonlinear systems and a continuous-time fuzzy-model-based controller is designed based on the extended parallel-distributed-compensation method. The digital controllers are determined from existing analogue controllers. The proposed method provides an accurate and effective method for digital control of continuous·time nonlinear systems and enables us to efficiently implement a digital controller via pre-determined continuous-time TS fuzzy-model-based controller. We have applied the proposed method to the balancing problem of the inverted pendulum to show the effectiveness and feasibility of the method.

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Effects of water-cement ratio on the freeze thaw resistance of fly ash concrete (물시멘트비에 따른 플라이애시 콘크리트의 동결융해 저항성에 관한 연구)

  • Kim, Do-Gyum;Lee, Jang-Hwa;Lee, Ho-Jae;Kim, Jae-Hwan
    • Proceedings of the Korea Concrete Institute Conference
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    • 2010.05a
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    • pp.211-212
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    • 2010
  • This study is aimed to investigate effects of water-cement ratio on the freeze thaw resistance of fly ash concrete. Assess the effects of physical properties of fly ash concrete by measure the length change, weight change, dynamic modulus of elasticity.

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Multi-Inernal Division Localization Algorithm by Edge Information for Indoor Wireless Sensor Network (실내 무선 센서 네트워크에서 모서리 정보를 고려한 다중 내분 위치인식 기법)

  • Lee, Ho-Jae;Lee, Sung-Jin;Lee, Sang-Hoon;Kim, Yeon-Soo
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.363-364
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    • 2008
  • Localization algorithms are required for indoor sensor network applications. In this paper, we introduce an efficient algorithm for low complexity and high accuracy, termed multi-internal division localization(MID), which emphasizes simple refinement and low system-load for low-cost and low-rate wireless sensors. We inspect MID algorithm through MATLAB simulation.

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Observer-based Fault Tolerant Controller Design for Multi-UAV Systems (다개체 무인 항공기 시스템을 위한 관측기 기반 고장포용제어기 설계)

  • Jee, Sung-Chul;Lee, Ho-Jae;Kim, Do-Wan
    • Journal of Institute of Control, Robotics and Systems
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    • v.18 no.5
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    • pp.407-412
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    • 2012
  • In this paper, we discuss an observer-based fault tolerant controller design for the unmanned aerial vehicle (UAV) systems with exogenous disturbance. To derive robust controller design conditions, we use $H_{\infty}$ design technique. The design conditions are derived in terms of linear matrix inequalities. An illustrative example is provided to show the effectiveness of the proposed methodology.

ESD damage mechanism of CMOS DRAM internal circuit and improvement of input protection circuit (정전기에 의한 CMOS DRAM 내부 회오의 파괴 Mechanism과 입력 보호 회로의 개선)

  • 이호재;오춘식
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.31A no.12
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    • pp.64-70
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    • 1994
  • In this paper, we inverstigated how a parricular internal inverter circuit, which is located far from the input protection in CMOS DRAM, can be easily damaged by external ESD stress, while the protection circuit remains intact. It is shown in a mega bit DRAM that the internal circuit can be safe from ESD by simply improving the input protection circuit. An inverter, which consists of a relatively small NMOSFET and a very large PMOSFET, is used to speed up DRAMs, and the small NMOSFET is vulnerable to ESD in case that the discharge current beyond the protection flows through the inverter to Vss or Vcc power lines on chip. This internal circuit damage can not be detected by only measuring input leakage currents, but by comparing the standby and on operating current before and after ESD stressing. It was esperimentally proven that the placement of parasitic bipolar transistor between input pad and power supply is very effective for ESD immunity.

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