• 제목/요약/키워드: Safe life design

검색결과 203건 처리시간 0.032초

Thruster Loop Controller design of Sun Mode and Maneuver Mode for KOMPSAT-2 (ICCAS 2004)

  • Choi, Hong-Taek;Oh, Shi-Hwan;Rhee, Seung-Wu
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2004년도 ICCAS
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    • pp.1392-1395
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    • 2004
  • In order to successfully develop attitude and orbit control subsystem(AOCS), AOCS engineer performs hardware selection, controller design and analysis, control logic and interface verification on electrical test bed, integrated system test, polarity test, and finally verification on orbit after launching. Attitude and orbit control subsystem for KOMPSAT-2 consists of standby mode, sun mode, maneuver mode, science mode, and power safe mode to stabilize and to control the spacecraft for performing the mission. The sun mode is usually divided into sun point submode, earth search submode and safe hold submode. The maneuver mode is divided into attitude hold submode and ${\triangle}$ V submode, while the science mode divided into science coarse submode and science fine submode. Moreover, it is added to back-up mode which uses wheels as an actuator for sun mode and maneuver mode. In this paper, we describe the controller design process and the performance of the design results with respect to the sun mode and the maneuver mode based on thrusters as an actuator using on flexible model.

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드럼 세탁기 Spider의 피로수명 신뢰성 평가에 대한 연구 (A Study on Reliability Estimation for Fatigue Life of the Spider from a Drum Washing Machine)

  • 이성민;조상봉;조성진;김영수;강동우;정연수;정보선
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2004년도 추계학술대회 논문집
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    • pp.46-49
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    • 2004
  • The spider of a drum washing machine receives the repeated fatigue loadings during laundering. Although the spider is designed statically safely, it often happens fatigue failure. Therefore it requires the safe design for fatigue and needs the prediction of quantitative fatigue life. The S-N diagram for a spider material is developed by fatigue test and statistical analysis. The stresses are measured directly from strain gages on the spider. To predict the fatigue life of spider, the rainflow counting method and Miner's rule are used. The data for fatigue life are analyzed statistically. From these data, reliability estimation for fatigue life can be done and also, equivalent fatigue life can be obtained. It will be applied to make and improve to a short period for design and prototype test.

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에이즈교육이 대학생의 에이즈에 대한 지식, 편견, 민감성,심각성, 안전한 성행위 의도에 미치는 영향 (Effects of AIDS Education on Knowledge, Prejudice, Susceptibility, Severity and Intention of Safe Sex Behavior among University Students)

  • 이종경
    • 한국보건간호학회지
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    • 제24권2호
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    • pp.258-269
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    • 2010
  • Purpose: This study investigated the effectiveness of AIDS education on knowledge, prejudice, susceptibility, severity, and intention of safe sex behavior among university students. Methods: This study was conducted from March, 2008 to May, 2008. The research design was a non-equivalent control group pre-post test. Participants 78 university students (control group) and 89 university students (experimental group). For the latter, AIDS education was provided once weekly for 1 h for 4 weeks. The educational program included understanding of sexuality, facts of AIDS, life stories of patients with AIDS, and safe sex behavior. The differences between two groups after education were analyzed by independent t-test. Results: The experimental group had significantly higher scores for knowledge, prejudice, susceptibility, and intention of safe sex behavior compared to the control group. However, no significant difference was found for severity between two groups. Conclusion: AIDS education can be effective in improving knowledge, prejudice, susceptibility, and intention of safe sex behavior, and is recommended as an effective AIDS education for university students.

An ultra-long-life small safe fast reactor core concept having heterogeneous driver-blanket fuel assemblies

  • Choi, Kyu Jung;Jo, Yeonguk;Hong, Ser Gi
    • Nuclear Engineering and Technology
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    • 제53권11호
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    • pp.3517-3527
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    • 2021
  • New 80-MW (electric) ultra-long-life sodium cooled fast reactor core having inherent safety characteristics is designed with heterogeneous fuel assemblies comprised of driver and blanket fuel rods. Several options using upper sodium plenum and SSFZ (Special Sodium Flowing Zone) for reducing sodium void reactivity are neutronically analyzed in this core concept in order to improve the inherent safety of the core. The SSFZ allowing the coolant flow from the peripheral fuel assemblies increases the neutron leakage under coolant expansion or voiding. The Monte Carlo calculations were used to design the cores and analyze their physics characteristics with heterogeneous models. The results of the design and analyses show that the final core design option has a small burnup reactivity swing of 618 pcm over ~54 EFPYs cycle length and a very small sodium void worth of ~35pcm at EOC (End of Cycle), which leads to the satisfaction of all the conditions for inherent safety with large margin based on the quasi-static reactivity balance analysis under ATWS (Anticipated Transient Without Scram).

착륙장치 피로 시험평가 (Fatigue Test and Evaluation of Landing Gear)

  • 이상욱;이승규;신정우;김태욱;김성찬;황인희;이제동
    • 대한기계학회논문집A
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    • 제36권10호
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    • pp.1181-1187
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    • 2012
  • 항공기 착륙장치의 피로설계에는 안전수명 방법이 적용된다. 즉, 균열이나 유해한 변형과 같은 구조적 결함이 항공기 운용수명 기간을 모사하는 피로 하중 스펙트럼 조건에서 발생하지 않아야 한다. 일반적으로 항공기 착륙장치는 고주기 피로 환경에 노출되므로, 설계 단계에서 착륙장치의 피로 수명은 응력 기반의 해석을 통해 예측한다. 이를 위해 재료의 분산(Scatter) 및 표면처리 특성 등을 고려한 설계 S-N 선도를 구성하여 해석에 사용한다. 시험평가 단계에서는 실물 착륙장치에 대한 피로시험을 통해 피로설계 요구조건 충족 여부를 최종 검증한다. 본 논문에서는 항공기 착륙장치의 피로수명 해석 및 시험절차를 실제 적용 사례를 통해 제시하였다.

Guidelines for Tall Buildings Development

  • Al-Kodmany, Kheir
    • 국제초고층학회논문집
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    • 제1권4호
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    • pp.255-269
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    • 2012
  • Tall buildings' implementation has often lacked urban design and architectural guidance. There are many examples of tall buildings that have been inappropriately located, designed, and built, and consequently dissatisfaction with high-rise development is wide-spread. This paper attempts to provide extensive urban and architectural guidelines in order to manage cityscape and to ensure safe and healthy living. Through recommendations on design and layout of tall buildings and open spaces the guidelines seek enhancing the visual experience, improving the microclimate conditions, and fostering active social life. These guidelines help in providing enjoyable urban experiences through the examination of spatial relationships, human scale, genius loci, perceptual characteristics, local identity, built heritage, economic activities, and social life.

안전한 주거환경 조성을 위한 범죄예방 환경디자인 제안 - 부산시 주거지역 골목길 사례를 중심으로 - (A Proposal for Crime Prevention Through Environmental Design for Making Safe Residential Environment - Focusing on Alleys in the Residential Area of Busan -)

  • 강승영;안수미;손광호
    • 한국실내디자인학회논문집
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    • 제23권6호
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    • pp.150-159
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    • 2014
  • Recently, violent crimes against the socially disadvantaged have become more frequent and became serious social issues. In addition, compared to the past, the crime methods have become more diverse and intricate, which results in larger damages. For those reasons, the public are increasingly concerned about crimes and it is detrimental to the quality of life in general. Currently, safety in alleys and other residential spaces is protected only by mechanical and managerial functions such as CCTV and police patrol. Safe environment from crimes can be achieved only if there are environmental and spatial plans such as CPTED (Crime Prevention through Environmental Design) principles. The purpose of this study is to propose a direction for spatial planning that can prevent crimes through environmental elements, by researching the spatial planning and current status of alleys and residential spaces from the viewpoint of CPTED. To do so, first, a review checklist was created based on five principles of CPTED and field surveys were conducted on the northern districts of Busan with high crime rates. Second, the problems were analyzed through the field surveys and checklist was classified based on five principles of CPTED to propose improvements for each item. Also, a computer graphic simulation was used to suggest a design proposal. We expect that the application of the basic environmental design principles and guidelines for CPTED will have the effect of creating crime-free and safe spaces in alleys and residential environment.

LNG탱크 겹침용접부의 피로강도에 관한 연구 (A Study on the Fatigue Strength of Lap Weld of LNG Tank)

  • 김종호
    • 한국해양공학회지
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    • 제13권3호통권33호
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    • pp.29-35
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    • 1999
  • At the design of Mark III membrane type LNG tank, an analytical and experimental approach on the fatigue strengths of membrane and its welds are very important in order to assist designers and surveyors. In this study, fatigue tests of lap weld of Mark III membrane type LNG tank were carried out and cumulative damage factor was calculated in order to estimate the fatigue life by probability density function and rule methods. It contained the following tests and reviews : 1) The fatigue tests of lap weld of stainless steel according to statistical testing method recommended by JSME, 2)Preparation of S-N curve for lap welds considering the statistical properties of the results of fatigue tests. 3) Procedure for estimating the initiation life of fatigue crack of lap welds under variable loads by the rule lf classification society and probability density function, 4) Guideline for inspection of lap welds fo membrane type LNG tank.

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동양 체질론의 감성적 기질을 이용한 안전 직무설계 (Job Design for Safety by Sensibility Based on the Oriental Human Constitution)

  • 최성운;이영석
    • 대한안전경영과학회지
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    • 제1권1호
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    • pp.29-39
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    • 1999
  • Human sensibility ergonomics is the technique that qualities man's sensibility, measures and evaluates it Quantitatively and makes man's life comfortable, safe and delightful by applying it to products or environmental projects. This study consider the sensibility factor of Sasang constitutional medicine, five elemental properties, and Biorhythm in terms of human sensibility ergonomics. And this study measure reaction-time dependent on a temperament or a state and evaluate the differences of reaction-times objectively with the comparison and analysis using the ANOVA. We can harness it for job design.

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고장 안전 특성을 가지는 내장형 AVTMR 시스템의 설계 및 RAMS 평가 (Design and RAMS Evaluation of embedded AVTMR System with Fail-safe Output Voter)

  • 김현기;이현태;이기서
    • 한국통신학회논문지
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    • 제30권5A
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    • pp.389-396
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    • 2005
  • 본 논문에서는 결함의 영향을 받지 않고, 결함이 발생하여도 안전측으로 동작할 수 있는 고장안전 보터(Fail-safe Voter)의 특성을 가지는 AVTMRWFSV(All Voting Triple Modular Redundancy With Fail-Safe Voter)시스템 구조를 설계하였으며, 마코브 모델링(Markov Modeling) 고장율에 따른 시스템의 RAMS(Reliability, Availability, Maintainability, Safety)를 평가하였다. 고장 안전 보터를 가지지 않은 AVTMR(All Voting Triple Modular Redundancy) 시스템과 AVTMRWFSV 시스템을 비교분석 하였고, 특히, 안전도(Safety)의 특성에 있어서 우수하다는 것을 보였으며, 설계된 AVTMRWFSV 시스템이 AVTMR보다 전반적인 시스템 평가에서 우수한 특성을 가진다는 것을 시뮬레이션을 통해 알 수 있었다. 이러한 AVTMRWFSV 시스템은 결함을 허용(Fault tolerant)하고, 고장 발생시 안전측으로 동작하는 특성을 가지기 때문에, 높은 신뢰성(Dependability)이나 안전성(safety)이 요구되는 통신 시스템이나 인간의 생명과 관련된 임베디드(Embedded) 철도통신 시스템, 선박 시스템이나 항공기 시스템에 적용될 수 있다.