• 한국전자통신학회논문지
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• 제10권9호
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• pp.1001-1008
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• 2015

본 논문은 안전 시스템의 구성하는 요소 중 전원 장치에 대한 안전 무결성 목표를 설정하고, 설정된 목표를 달성하기 위한 전원 장치의 구조를 설계하였다. 해당 안전 시스템은 안전 최고 등급인 SIL4(Safety Integrity Level 4)를 목표로 하였으며, 철도 응용 분야의 규격인 IEC 62425에 부합하는 구조 설계 및 변경 프로세스를 정립하여 6단계의 기본 구조 설계 방안을 적용하였다. 본 연구에서는 전원 장치의 고장으로부터 시스템의 안전 무결성을 유지할 수 있는 전원 장치의 구조를 FMEA(Failure Modes and Effect Analysis) 기법을 사용하여 도출하였으며, 해당 결과를 적용한 전원 장치는 안전 시스템에 적용할 수 있다는 것을 제시하였다. 최종적으로 전원 장치 모듈에 대한 고장빈도의 정량적 목표치를 제시하였다.

• 대한안전경영과학회지
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• 제16권4호
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• pp.123-131
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• 2014

Modern weapon systems are getting more complex in terms of the functionality and also the conditions on the environment and range in which they are deployed and used. Therefore, many development programs can easily be exposed to a variety of risks, resulting in delayed schedules and cost overrun. As such, effective means are necessary to keep the defence budget at an affordable level while competitive edges on technological aspects are retained. As one way to meet those need, modeling and simulation (M&S) methods have widely been used, particularly in the test and evaluation (T&E) process for weapon systems development. The result of M&S-based systems development should be evaluated by the verification, validation & accreditation (VV&A) process to assure keeping reliability at a desired level. On the other hand, due to the explosiveness, the weapons systems development naturally requires to consider safety issues in both the T&E and operational periods. The purpose of this paper is to improve the VV&A process by reflecting the safety requirements therein. To do so, the VV&A process has been analyzed and graphically modeled first and then safety elements have been incorporated effectively. The use of the improved process in the war ships development has also been discussed. Based on the process proposed and the consequent database constructed, the target system can be expected to benefit from reducing development risks while assuring systems safety.

• Safety and Health at Work
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• 제1권2호
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• pp.192-200
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• 2010

Objectives: We have investigated the toxic effects of the inhalation of subchronic and acute levels of n-octane. Methods: The rats were exposed to n-octane of 0, 2.34, 11.68 and 23.36 mg/L (n = 5 rats/group/gender) in an acute inhalation test (Organization for Economic Co-operation and Development (OECD) TG 403), or to 0, 0.93, 2.62 and 7.48 mg/L (n = 10 rats/group/gender) for a subchronic inhalation test (OECE TG 413), to establish a national chemical management system consistent with the Globally Harmonized Classification System (GHS). Results: Acutely-exposed rats became lethargic but recovered following discontinuation of inhalation. Other clinical symptoms such as change of body weight and autopsy finds were absent. The LC50 for the acute inhalation toxicity of n-octane was determined to exceed 23.36 mg/L and the GHS category was 'not grouping'. Subchronically-treated rats displayed no significant clinical and histopathological differences from untreated controls; also, target organs were affected hematologically, biochemically and pathologically. Therefore, the no observable adverse effect level was indicated as exceeding 7.48 mg/L and the GHS category was 'not grouping' for the specific target organ toxicity upon repeated exposure. Conclusion: However, n-octane exposure should be controlled to be below the American Conference of Industrial Hygienists recommendation (300 ppm) to prevent inhalation-related adverse health effects of workers.

• 자동차안전학회지
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• 제6권1호
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• pp.27-32
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• 2014

A study assessing driver acceptance level for various active safety systems against Korean drivers has been conducted. A 2013 Cadillac ATS model vehicle was tested along southern outskirt of Seoul including local roadway and interurban highway. Active safety systems included were FCA(Forward Collision Alert), LDW(Lane Departure Warning), SBZA(Side Blind Zone Alert), FRPA(Front/Rear Park Assist), RCTA(Rear Cross Traffic Alert), ACC(Adaptive Cruise Control), and AEB(Autonomous Emergency Braking). Participants experienced the FRPA, RCTA and AEB features in a controlled parking lot with a dummy vehicle and traffic cones as target obstacles. Remaining features have been tested on the accumulated stretched of 106 km long urban and interurban roadway. Series of questionnaires corresponding to each active safety systems have been conducted. Tentative results revealed that RCTA and SBZA systems received favourable ratings compared to the other ones.

• Smart Structures and Systems
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• 제33권1호
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• pp.27-39
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• 2024

The effectiveness of conventional tuned liquid dampers (TLDs) in controlling the wind-induced response of tall flexible structures has been indicated. However, the impaired control effect in the detuning condition or a considerably high mass cost of liquid may be incurred in ensuring the high-level serviceability. To provide an efficient TLD-based solution for wind-induced vibration control, this study proposes a serviceability-oriented optimal design method for isolated TLDs (ILDs) and derives analytical design formulae. The ILD is implemented by mounting the TLD on the linear isolators. Stochastic response analysis is performed for the ILD-equipped structure subjected to stochastic wind and white noise, and the results are considered to derive the closed-form responses. Correspondingly, an extensive parametric analysis is conducted to clarify a serviceability-oriented optimal design framework by incorporating the comfort demand. The obtained results show that the high-level serviceability demand can be satisfied by the ILD based on the proposed optimal design framework. Analytical design formulae can be preliminarily adopted to ensure the target serviceability demand while enhancing the structural displacement performance to increase the safety level. Compared with conventional TLD systems, the ILD exhibits higher effectiveness and a larger frequency bandwidth for wind-induced vibration control at a small mass ratio.

• 대한안전경영과학회지
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• 제11권1호
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• pp.115-120
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• 2009

Single PPM Quality Innovation Movement is originally developed quality program in Korea for supplier's quality level-up since 1995. The quality target is below the 10ppm(parts per million) in outgoing quality and delivered goods plus field claim. This Single PPM Quality Innovation Movement program was conducted to realize the anticipated results not only due to management result level's increasing, but also the company's confidence and competitiveness. This study attempted to find the mutual influences on the participation of the constituent members, satisfaction of the constituent members and results of the management from Single PPM Quality Innovation Movement. The reliance analysis for the measurement material on the questionnaire was verified by Cronbach's alpha coefficient. Participation of the constituent members, satisfaction of the constituent member and result of the management, the influences upon Single PPM improvement degree level were verified through the structural analysis by using SPSS statistic package. The influence evaluation among the groups was evaluated by the structure equation.

• 한국컴퓨터정보학회논문지
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• 제28권1호
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• pp.55-63
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• 2023

본 논문에서는 재난 위기경보 발령을 하기 위해 상황판단 기준을 자동분석하는 재난위기경보관리시스템의 기능 및 서비스와 국가재난관리정보시스템(NDMS) 체계에서 운영하기 위한 방안을 제안한다. 재난 발생시 위험수준에 따라 위기경보(관심-주의-경계-심각)를 발령하고 있다. 위기경보 수준을 자동분석 판단하기 위해 첫째, 데이터 수집, 위기경보 수준 분석, 위기경보 수준 판단, 공간규모별(시도, 시군구) 위기경보 등급을 표출하는 재난위기경보관리시스템을 구현하였다. 위기경보 수준 판단은 지능형 위기경보 수준(지역민감도, 위험수준, 위기경보 등급 판단)과 위기관리 매뉴얼의 위기경보 기준(시도 단위 기준 표준 설정)을 적용하여 두 가지 방식으로 분석하여 표출한다. 둘째, 국가재난정보관리시스템내에서 운영할 수 있도록 재난안전데이터 공유 플랫폼의 데이터 연동과 위기경보 데이터를 공동활용하기 위해 표준 메타데이터(구성항목 정의), 상황정보 연계(대상 정의), 데이터 제공을 위한 openAPI 표준을 제시한다.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제53권2호
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• pp.99-106
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• 2004

Train control system in LRT (Light Rail Transit) is developed as a part of "Light Rail Transit System Development Project". But there was no specific requirement representing the system safety. Because system safety must be ensured before the customization, we applied the system to a officially recognized specific procedure, such as "A Guideline to Ensure the Safety of Train Control System in Korea" that was officially announced by KNR (Korea National Railroad) in 2001. We should draw system safely requirement to guarantee system safety for the first time. In this paper, the hazard identification and analysis to derive the safety requirement on LRT train control system are carried out following the KNR guideline. To analyze hazard, we have to deduce system functions, identify related hazards, derive the effects of the hazards, analyze current risk, define the target risk of the system, and deduce the alternative plans to reduce the effects of the hazards. After the hazard analysis following the upper procedure, 30 hazards are identified and analysed. Especially detailed analysis on train collision that is a main hazard of the train control of system is specially carried out.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.434-439
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• 1993

This paper present a sensor based obstacle avoidance method which is based on a VFH(Vector Field Histogram) method. The basic idea of obstacle avoidance is to find a minimum obstacle direction and distance. From the minimum sonar index and the target direction high level system determine steering angle of mobile robot. The sonar sensor system consists of 12 ultra sonic sensor, and each sensor have its direction and safety value. This method has advantage on calculation speed and small memory. This method is implemented on indoor autonomous vehicle'ALiVE-2'.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.389-389
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• 2000

The number of automobiles is rapidly increasing , as are the importance of the car as a way of transportation, and the variety of its uses. In these surroundings, a safety, one of the primary factors which must be considered in automotive engineering, demands a system that aids the driver's vision and perception. In this point of view, development of the more promoted system that complement the existing passive method which relies on just man's ability is the important issue of the advanced traffic system including ITS. In this paper, we provide an algorithm and implementation of a control system that warns the collisions ahead and avoids this situation, using informations about the host-car, target-car and surroundings. The warning is made by an algorithm that decides the degree of safely. With this degree of safely, the controller automatically controls a vehicle's speed to a proper level.