• Title/Summary/Keyword: 김두현

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Damage and Failure Characteristics of Semiconductor Devices by ESD (ESD에 의한 반도체소자의 손상특성)

  • 김두현;김상렬
    • Journal of the Korean Society of Safety
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    • v.15 no.4
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    • pp.62-68
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    • 2000
  • Static electricity in electronics manufacturing plants causes the economic loss, yet it is one of the least understood and least recognized effects haunting the industry today. Today's challenge in semiconductor devices is to achieve greater functional density pattern and to miniaturize electronic systems of being more fragile by electrostatic discharges(ESD) phenomena. As the use of automatic handling equipment for static-sensitive semiconductor components is rapidly increased, most manufacturers need to be more alert to the problem of ESD. One of the most common causes of electrostatic damage is the direct transfer of electrostatic charge from the human body or a charged material to the static-sensitive devices. To evaluate the ESD hazards by charged human body and devices, in this paper, characteristics of electrostatic attenuation in domestic semiconductor devices is investigated and the voltage to cause electronic component failures is investigated by field-induced charged device model(FCDM) tester. The FCDM simulator provides a fast and inexpensive test that faithfully represents ESD hazards in plants. Also the results obtained in this paper can be used for the prevention of semiconductor failure from ESD hazards.

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A Study on Heat-Flux Evaluation for Cable Fire Including Diagnostic Methodology for Degradation in Nuclear Power Plants (원전 케이블 화재 열속평가 및 열화 진단방법에 관한 연구)

  • Lim, Hyuk-Soon;Kim, Doo-Hyun
    • Journal of the Korean Society of Safety
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    • v.26 no.2
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    • pp.20-25
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    • 2011
  • The fire event occurred in fire proof zone often causes serious electrical problems such as shorts, ground faults, or open circuits in nuclear power plants. These would be directed to the loss of safe shutdown capabilities performed by safety related systems and equipments. The fire event can treat the basic design principle that safety systems should keep their functions with redundancy and independency. In case of a multi-core cable fire, operators can not perform their mission properly and can misjudge the situation because of spurious operation, wrong indication or instrument. These would deteriorate the plant capabilities of safety shutdown and make disastrous conditions. In this paper, the characteristic of cable fire is investigated and the heat-flux evaluation for cable fire is studied. Moreover, a diagnostic methodology for degraded cable in nuclear power plants is presented.

A Case of Idiopathic Isolated Hypoglossal Nerve Palsy (특발성 단독설하신경마비 1례)

  • Kim, Doo-Hyun;Lee, Se-Jin
    • Journal of Yeungnam Medical Science
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    • v.27 no.1
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    • pp.74-77
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    • 2010
  • Isolated hypoglossal nerve palsy is a rare clinical condition and it causes deviation of the tongue and dysarthria. A 50-year-old female presented with tongue deviation to the left and mild dysarthria. She had no remarkable past medical history except several recent upper respiratory infections. On examination, the other cranial nerves were intact and she had no focal neurological signs. The findings of MRI and MR angiography were normal. Cerebrospinal fluid analysis revealed only mild elevation of protein. We diagnosed her as suffering with idiopathic isolated hypoglossal nerver palsy and we administered steroid therapy. The dysarthria was improved, but the tongue deviation still remained at 50 days after onset. We report here on a rare case of idiopathic isolated hypoglossal nerve palsy.

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A Design and Implementation of Firewall System for Virus Detection in Network (네트워크상의 바이러스 탐지를 위한 방화벽 시스템 설계 및 구현)

  • Choi, Jun-Ho;Kim, Doo-Hyun;Kim, Pan-Koo;Kwon, Suck-Chun
    • Proceedings of the Korea Information Processing Society Conference
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    • 2001.04b
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    • pp.1069-1072
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    • 2001
  • 인터넷 사용의 증가와 더불어 컴퓨터 바이러스의 제작기법의 지능화 및 그로 인한 피해가 날로 확산됨에 따라 시스템 사용자들의 바이러스 탐지에 대한 어려움은 증가되고 있으며, 또한 개인용 컴퓨터뿐만 아니라 서버급 컴퓨터를 겨냥한 신종 바이러스가 계속 증가함으로 이에 대한 대비책이 시급한 상황이다. 이에 본 논문에서는 네트워크 상의 바이러스 탐지를 위해 방화벽 시스템을 도입하여 네트워크 보안을 유지하며 네트워크 상에서 유입되는 파일의 바이러스 진단 및 치료의 과정을 효과적으로 수행 할 수 있는 시스템을 제안한다.

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A Study on the Techniques of Temporal-Fidelity Scaling for Dynamic QoS Adaptation (동적 QoS 적응을 위한 Temporal-Fidelity Scaling 기법에 관한 연구)

  • Kim, Hyun-Jeong;Lee, Heung-Ki;Son, Ho-Shin;Yoo, Woo-Jong;Kim, Do-Hyon;Yoo, Kwan-Jong
    • Proceedings of the Korea Information Processing Society Conference
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    • 2000.10a
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    • pp.691-694
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    • 2000
  • 인터넷을 통한 정보 전송이 급증하고 있는 오늘날 멀티미디어 데이터 전송 또한 상당 부분을 차지하고 있다. 그러나 네트워크 대역폭이 보장되지 않고 유동적인 인터넷상에서 실시간으로 멀티미디어 정보를 전송하는 것은 여러 가지 문제점을 안고 있다. 이에 멀티미디어 데이터의 스케일러블 전송에 대한 연구가 등장하게 되었다. 본 논문에서는 동적으로 변하는 네트워크 QoS에 따라 MPEG 비디오 스트림의 스케일러블 전송이 가능하도록 하는 Temporal-Fidelity Scaling 기법에 대해 제안하고자 한다.

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A Study on Layered Streaming Service based on TCP/UDP for Multimedia Data Transport (멀티미디어 데이터 전송을 위한 TCP/UDP 기반의 Layered Streaming Service에 관한 연구)

  • Kim, Sang-Hyong;Sinn, Jeong-Ah;Cho, Jae-Sang;Lee, Sung-In;Yoo, Won-Kyong;Yoo, Kwan-Jong;Kim, Doo-Hyun
    • Proceedings of the Korea Information Processing Society Conference
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    • 2003.11b
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    • pp.1225-1228
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    • 2003
  • 인터넷의 급속한 확산과 통신 기술의 발전에도 불구하고 제한된 통신망의 자원을 최대한 이용하여 대용량의 멀티미디어 데이터를 서비스하고자 하는 계층적 서비스 기술들이 각광을 받고 있다. 이에 본 논문에서는 현재까지 이루어진 MPEG-4 미디어 데이터의 계층화 기법을 이용하여 분할된 스트리밍 데이터를 가변적인 네트웍 환경에 원활하게 서비스할 수 있는 TCP/UDP 기반의 스트리밍 서비스를 활용한 시스템의 구성을 제안한다.

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Experimental Power Consumption Measurement of H.264 Decoder Functions using Qplus/Esto (QplusME/Esto를 이용한 H.264 디코더의 함수별 전력 측정)

  • Chae Song-Ah;Kim Doo-Hyun;Lim Chae-Duk;Woo Duk-Kyun;Jung Chang-Hee
    • Proceedings of the Korean Information Science Society Conference
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    • 2006.06a
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    • pp.247-249
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    • 2006
  • 본 논문에서는 임베디드 리눅스와 그에 따른 통합 개발 환경인 QpusME/Esto에서 제공하는 전력소모량 분석도구를 이용하여 H.264 디코더의 함수별 전력 소모량을 측정하여 공개함으로써 향후 연구에 기반 정보로 사용하도록 한다. 또한 이를 이용하여 MacroBlock 디코딩시, 전력을 줄일 수 있는 다양한 방법 중 하나의 예를 제시하고 그 실험 결과를 제시한다.

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A Study on The Security Measures of The 17th FIFA World Cup in 2002 (2002년월드컵축구대회에 대한 안전대책)

  • Kim, Doo-Hyun
    • Korean Security Journal
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    • no.2
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    • pp.33-60
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    • 1999
  • I Study on the security measures of the World Cup Korea and Japan jointly in 2002. The paper, purporting to consider security counterplans, comprise five chapters. Chapter I which sets out purpose, scope and method, is followed by chapter II, dealing largely with the legislations and importance on the security measures of the 17th FIFA World Cup in 2002. Chapter III concerns the security environment -internal environment, external environment- and the highlights accidents and events of history on the FIFA World Cup. Chapter IV consider security measures of the World Cup Korea in 2002. It is followed by concluding observation made in chapter V. To be operated security systems effectively, these need to be regulated according to a security measures organizations, security facilities and equipments, security plan and protective force, security operations and so forth.

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Development of Powertrain Model for Vehicle Dynamic Analysis Program, AutoDyn7 (차량동역학 해석 프로그램 AutoDyn7의 동력전달장치 모델)

  • 손정현;유완석;김두현
    • Transactions of the Korean Society of Automotive Engineers
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    • v.9 no.2
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    • pp.185-191
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    • 2001
  • In many papers, the powertrain system generally has been madeled as one-dimensional torque model. One-dimensional powertrain model may calculate the torque correctly but it does not consider the non-rotational degrees-of-freedom of the powertrain components and the interaction of these degrees-of-freedom with the vehicle body frame and suspension. To consider the non-rotational degrees of freedom, the differential is modeled as a three-dimensional rigid body in this paper. A constant velocity joint is newly formulated and a relative constraint is also formulated to model the motion transfer due to gear ratio of the differential. Implementing the proposed powertrain system in the multibody model, more detail dynamic responses can be obtained. Obtained outputs such as reaction torques on the constant velocity joint and reaction forces on the rack can be useful data in the design of a powertrain.

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An Electrical fire Diagnosis System Using the Mixed Approach of the Case-Based Reasoning with the Knowledge-Based Reasoning (지식기반 추론과 사례기반 추론의 혼합 적용 기법을 이용한 전기화재 원인진단 시스템)

  • 권동명;김두현;김상철;김상렬
    • Proceedings of the Korean Institute of Industrial Safety Conference
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    • 1999.06a
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    • pp.223-228
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    • 1999
  • This paper presents an electrical fire diagnosis system using intellectual reasoning which is the mixed approach of the case-based reasoning with the knowledge-based reasoning A prototype system is implemented using Delphi, one of the program development tools under windows environment, for making an application program for database. And database is builded using Paradox. The results of applying the system to some imaginary fire cases to verify its capability and validity show that the causes of fires is successfully diagnosed, so the proposed system proves to be reasonable.

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