• 제목/요약/키워드: Fail-Safety system

검색결과 94건 처리시간 0.026초

ERP 구축 후 사용자만족도에 관한 사례연구 (A case study about the user's degree of satisfaction after ERP Implementation)

  • 문찬오;김창은
    • 대한안전경영과학회지
    • /
    • 제10권2호
    • /
    • pp.175-185
    • /
    • 2008
  • The research it sees the many enterprises ERP system Go-Live after, which fail are appearing to are actuality plentifully with continuous change management insufficiency. One objective of the research it sees the ERP system effect leads simple with successful ERP system embodiment end me, the thing knows, the successful change management to ERP system Go-Live after and there is report that the effect appears. The ERP system Go-Live after the domestic enterprise 2 year above is analysis about the user's degree of satisfaction.

도시철도 신호시스템 설계에서의 운전시격 향상에 대한 연구 (The Study of Headway Improvement on Signaling System Des19n of Urban Transit)

  • 백종현;안태기;정락교;한성호;변윤섭;박현준
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1999년도 하계학술대회 논문집 A
    • /
    • pp.492-494
    • /
    • 1999
  • To improve safety operation of urban transit, compatible design of signaling system is most important factor at future train operation and management. Therefore, signaling system should be designed compatible transport demand of target year. In addition, signaling system should be designed improved train safety, based fail-safe principle. Most of all, to solve passenger concentration, high density and to improve efficiency of train operation. Headway improvement of train is most important. Train organization length of new urban transit as light rail is generally shorter than EMU. Therefore, to increase passenger service and operation efficiency, minimum headway of one minute in this system should be important required.

  • PDF

Concept definition of Small-Medium Reactor Coolant System using System Engineering

  • Park, Jung Hwan;Jung, Jae Cheon
    • 시스템엔지니어링학술지
    • /
    • 제10권1호
    • /
    • pp.33-41
    • /
    • 2014
  • New design concept of Reactor Coolant System (RCS) including a reactor assembly for the SMR is introduced in this work. An exploration of new type of reactor that is advanced from proposed SMRs is performed by using systems engineering approach. In this point of view project structured on three main phases; needs analysis (NA), concept exploration (CE), and concept definition (CD). Main objectives as an output of the CE stage are a small size, low cost, shortening the schedule, and enhancing safety. The SMRs usually have a small size requirement. In order to meet the size requirement and to achieve a productivity, in other words, easiness to manufacture, this paper suggests an integrated PWR design concept through researching predecessors. Although the integrated PWR concept provides many advantages, it has disadvantages that composite of maintenance and a low availability problem. Therefore, this paper comes up with a run-to-fail design concept based on modular design to address the maintenance problem and to maximize the availability of SMRs as well as to be compatible with the overall-SMRs including Barge Mounted(BM)type.

Quantitative Reliability Assessment for Safety Critical System Software

  • Chung, Dae-Won
    • Journal of Electrical Engineering and Technology
    • /
    • 제2권3호
    • /
    • pp.386-390
    • /
    • 2007
  • At recent times, an essential issue in the replacement of the old analogue I&C to computer-based digital systems in nuclear power plants becomes the quantitative software reliability assessment. Software reliability models have been successfully applied to many industrial applications, but have the unfortunate drawback of requiring data from which one can formulate a model. Software that is developed for safety critical applications is frequently unable to produce such data for at least two reasons. First, the software is frequently one-of-a-kind, and second, it rarely fails. Safety critical software is normally expected to pass every unit test producing precious little failure data. The basic premise of the rare events approach is that well-tested software does not fail under normal routine and input signals, which means that failures must be triggered by unusual input data and computer states. The failure data found under the reasonable testing cases and testing time for these conditions should be considered for the quantitative reliability assessment. We presented the quantitative reliability assessment methodology of safety critical software for rare failure cases in this paper.

A Study on Design of the Trip Computer for ECC System Based on Dynamic Safety System

  • Kim, Seog-Nam;Seong, Poong-Hyun
    • Nuclear Engineering and Technology
    • /
    • 제32권4호
    • /
    • pp.316-327
    • /
    • 2000
  • The Emergency Core Cooling System in current nuclear power plants typically has a considerable number of complex functions and largely cumbersome operator interfaces. Functions for initiation, switch-over between various phases of operation, interlocks, monitoring, and alarming are usually performed by relays and analog comparator logic which are difficult to maintain and test. To improve problems of an analog based ECC (Emergency Core Cooling) System, the trip computer for ECCS based on Dynamic Safety System (DSS) is implemented. The DSS is a computer based reactor protection system that has fail-safe nature and performs a dynamic self-testing. The most important feature of the DSS is the introduction of test signal that send the system into a tripped state. The test signals are interleaved with the plant signals to produce an output which switches between a tripped and health state. The dynamic operation is a key feature of the failsafe design of the system. In this work, a possible implementation of the DSS using PLC is presented for a CANDU Reactor. ECC System of the CANDU Reactor is selected as the reference system.

  • PDF

추진시스템 종합성능시험에서의 엔진부 비상정지 설정 (Emergency Blockage Application of Engine Part for Integrated Propulsion Performance Test)

  • 하성업;이정호;권오성;김병훈;강선일;한상엽
    • 한국추진공학회:학술대회논문집
    • /
    • 한국추진공학회 2003년도 제20회 춘계학술대회 논문집
    • /
    • pp.171-176
    • /
    • 2003
  • 추진시스템 종합성능시험을 위한 시험시설이 구축되었으며, 최소계측을 통하여 최대한의 안전을 확보하기 위한 비상정지시스템이 검토되었다. 이에 연소실압력과 가속도신호를 이용한 비상정지시스템이 구축되었고, 이 측정변수를 통하여 점화지연 및 실패, 소화, 추진제공급상태, 불안정연소, 과도 구조진동 등을 감시할 수 있었으며, 시험 중 빠른 판단 및 조치에 의하여 시험의 안전을 확보할 수 있었고, 목적한 종합성능시험을 안전하게 완료할 수 있었다.

  • PDF

산업안전·위생지도사 제도 및 운영에 대한 인식도 조사연구 (Survey on the Industrial Safety & Hygiene Consultant System and It's Operational Issues)

  • 원정일;박종태
    • 한국산업보건학회지
    • /
    • 제15권3호
    • /
    • pp.192-201
    • /
    • 2005
  • The Korean government had introduced the industrial safety & hygiene consultant(ISHC) system to improve worksite health and safety level by providing specialized industrial safety & hygiene(S&H) services in 1996. Despite of initial hopeful expectation it has been said that this plan might fail to settled down and maintain its purpose. This study was designed to investigate operational issues and problems concerning the ISHC system, that would direct the way of change and future role. Questionnaire were sent to ISHC, professional engineer, agencies for occupational injury prevention, S&H specialist in the corporation nationwide and totally 256 people responded to in having 62.7% of response rate. The result of this study were as follows; 1. One hundred and forty two cases of safety assessment and 27 cases of process safety reports were the six years' results since 1996 the ISHC program had first been introduced. This results showed that injury prevention activities of ISHC had been stagnant. 2. The 78.8% of respondents had negative opinion about injury prevention activities of ISHC program. 3. The operational problems of ISHC were lack of understanding of company about ISHC, low systematization of work items, duty overlapping with agencies for occupational injury prevention, low support by government. in order. 4. It was suggested that abolition of ISHC and promotion of professional engineer system should be considered. 5. To promote professional engineer system it was suggested that the professional engineer could conduct consulting service and ISHC should be integrated with the expert system.

IPPT, SQT에서의 엔진부 비상정지 시스템 설계 및 운용 (Design and Application of Emergency Blockage System for Engine Part at IPPT and SQT)

  • 하성업;이중엽;정태규;한상엽
    • 한국추진공학회지
    • /
    • 제7권2호
    • /
    • pp.44-53
    • /
    • 2003
  • KSR-III의 추진시스템 종합성능시험과 단인증시험을 위한 수직형 연소시험시설이 구축되었다. 이러한 시험은 발사체에 준하는 단품을 사용하는 시험으로, 상대적으로 낮은 수준의 안전율 하에서 시험이 진행되게 된다. 이에 연소시험 안전대책의 하나로 엔진부에 대한 비상정지 시스템이 검토되었으며, 정확하고 빠른 판단을 위하여 연소실 압력과 가속도신호를 사용하는 비상정지 시스템이 구축되었다. 이러한 측정변수를 통하여 점화지연 및 실패, 소화, 추진제 공급상태, 불안정 연소, 구조물 과도진동 등을 감시할 수 있었으며, 이상 상황인지 후 빠르게 시험을 중단할 수 있었다. 이처럼 빠른 판단과 후속조치로 시험의 안전을 확보할 수 있었으며, 목적한 개발시험을 안전하게 마칠 수 있었다.

라이다를 이용한 고층 건물의 변위 계측 기법에 관한 연구 (A Study on the Displacement Measuring Method of High-rise Buildingas using LiDAR)

  • 이홍민;박효선
    • 한국전산구조공학회:학술대회논문집
    • /
    • 한국전산구조공학회 2006년도 정기 학술대회 논문집
    • /
    • pp.151-158
    • /
    • 2006
  • Structural health monitoring is concerned with the safety and serviceability of the users of structures, especially for the case of building structures and infrastructures. When considering the safety of a structure, the maximum stress in a member due to live load, earthquake, wind, or other unexpected loadings must be checked not to exceed the stress specified in a code. It will not fail at yield, excessively large displacements will deteriorate the serviceability of a structure. To guarantee the safety and serviceability of structures, the maximum displacement in a structures must be monitored because actual displacement is a direct assessment index on its stiffness. However, no practical method has been reported to monitor the displacement, especially for the case of displacement of high-rise buildings because of not to easy accessive. In this paper, it is studied displacement measuring method of high-rise buildings using LiDAR The method is evaluated by analyzing accuracy of measured displacements for existing building.

  • PDF

자율주행 자동차의 제어권 전환 시간 확보를 위한 차간 통신 기반 종방향 제어 알고리즘 개발 (Development of a Longitudinal Control Algorithm based on V2V Communication for Ensuring Takeover Time of Autonomous Vehicle)

  • 이혜원;송태준;윤영민;오광석;이경수
    • 자동차안전학회지
    • /
    • 제12권1호
    • /
    • pp.15-25
    • /
    • 2020
  • This paper presents a longitudinal control algorithm for ensuring takeover time of autonomous vehicle using V2V communication. In the autonomous driving of more than level 3, autonomous systems should control the vehicles by itself partially. However if the driver's intervention is required for functional safety, the driver should take over the control reasonably. Autonomous driving system has to be designed so that drivers can take over the control from autonomous vehicle reasonably for driving safety. In this study, control algorithm considering takeover time has been developed based on computation method of takeover time. Takeover time is analysed by conditions of longitudinal velocity of preceding vehicle in time-velocity plane. In addition, desired clearance is derived based on takeover time. The performance evaluation of the proposed algorithm in this study was conducted using 3D vehicle model with actual driving data in Matlab/Simulink environment. The results of the performance evaluation show that the longitudinal control algorithm can control while securing takeover time reasonably.