• Title/Summary/Keyword: Safety function

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Review of Acceptance Sampling Plans for Parts Per Million Fraction of Defectives (PPM 부적합품률의 샘풀링 검사 계획의 고찰)

  • Choi, Sung-Woon
    • Journal of the Korea Safety Management & Science
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    • v.9 no.4
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    • pp.137-142
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    • 2007
  • This paper is to introduce attribute acceptance sampling plan based on statistical inference of binomial proportions such as PPM or PPB. In addition, this paper presents three variable sampling acceptance sampling plans based on $C_{pm},\;C_{pmk}$, and Taguchi's loss function. Producers are able to consider as not only external vendors but also internal customers.

Implementation and Application of Integrated Model for ALT(Accelerated Life Test) (ALT 통합모형의 적용 및 응용)

  • Choi, Sung-Woon
    • Proceedings of the Safety Management and Science Conference
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    • 2008.11a
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    • pp.153-160
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    • 2008
  • This paper presents the log likelihood function for integrated models for ALT such as exponential-general Eyring, Weibull-temperature and specific heat, lognormal-temperature and specific heat. Additionally this paper estimates the system reliability and mean time to failure(MTTF) for series, parallel, k of n, and standby system using ALT linkage parameter. Lastly this study designs three variable reliability acceptance sampling(RAS) plans such as type I, II censored test, sequential test by the use of integrated models for ALT.

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A Study on Development of Safety Index for Evaluating Railway Safety(I) (철도안전도 평가지수 개발에 관한 연구(I) - 안전목표 및 안전지수에 관하여 -)

  • Song, Bo-Young;Lee, Dong-Hoon;Moon, Dae-Seop;Lee, Hi-Sung;Kim, Man-Ung
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.1657-1667
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    • 2007
  • This study propose a model for railway safety evaluation with which the safety of whole railway system can be evaluated. The evaluation model is to generate a safety index which quantitatively represent the degree of railway safety. Safety index is proposed a function of three indexes; an accident index, safety management index, and safety culture index. This paper describes the first result from the study on the safety target which will be a key starting point toward the development of safety evaluation model. It is recommended that the safety target be composed of several sub-targets that are apportioned to constituent components. It is concluded that the classification of safety target influence on deciding components or attributes that constitute each sub-indexes; an accident index, safety management index, and safety culture index. Based on this study, a railway safety evaluation model will be developed in the next study.

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EPLA(Electric Park Lock Actuator) System Safety Design Based on Vehicle Functional Safety Standard ISO 26262

  • Eun-Hye Shin;Hyun-Hee Kim;Kyung-Chang Lee
    • Journal of the Korean Society of Industry Convergence
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    • v.26 no.2_1
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    • pp.239-248
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    • 2023
  • In this paper, we conduct a study on the design that can secure the safety of the EPLA system by performing safety activities based on the ISO 26262 standard for vehicle functional safety. In the case of a company developing a detailed system, it is responsible for verification through hardware design and safety analysis in the overall flow of safety activities, and safety analysis according to the ASIL safety level must be properly performed. At this time, there are cases where the safety goal quantitative metric value suggested by the ISO 26262 standard cannot be satisfied only by the hardware design of the basic function, so it is necessary to design and install the safety mechanism. Based on ISO 26262 safety activities, it is possible to derive an effective design plan through hardware safety analysis.

Effect of seismic design level on safety against progressive collapse of concentrically braced frames

  • Rezvani, Farshad Hashemi;Asgarian, Behrouz
    • Steel and Composite Structures
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    • v.16 no.2
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    • pp.135-156
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    • 2014
  • In this research the effect of seismic design level as a practical approach for progressive collapse mitigation and reaching desired structural safety against it in seismically designed concentric braced frame buildings was investigated. It was achieved by performing preliminary and advanced progressive collapse analysis of several split-X braced frame buildings, designed for each seismic zone according to UBC 97 and by applying various Seismic Load Factors (SLFs). The outer frames of such structures were studied for collapse progression while losing one column and connected brace in the first story. Preliminary analysis results showed the necessity of performing advanced element loss analysis, consisting of Vertical Incremental Dynamic Analysis (VIDA) and Performance-Based Analysis (PBA), in order to compute the progressive collapse safety of the structures while increasing SLF for each seismic zone. In addition, by sensitivity analysis it became possible to introduce the equation of structural safety against progressive collapse for concentrically braced frames as a function of SLF for each seismic zone. Finally, the equation of progressive collapse safety as a function of bracing member capacity was presented.

Changes of Pulmonary Function and Biopersistence Evaluation of Sepiolite in Sprague-Dawely Rats (랫드에 주입된 세피오라이트에 의한 폐기능 변화 및 생체내구성 평가)

  • Chung, Yong Hyun;Han, Jeong Hee;Sung, Jae Hyuck;Yu, Il Je
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.16 no.4
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    • pp.303-313
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    • 2006
  • Two kinds of sepiolite (sepiolite 1, sepiolite 2), a $500^{\circ}C$ heat treated sepiolite (sepiolite 500), and a $700^{\circ}C$ heat treated sepiolite (sepiolite 700) were analyzed for their physicochemical properties. After these sepiolites were instilled into rat lungs, the effects of these substances on lung function and biochemical changes were evaluated. In addition, the fibers in the lungs were counted and characterized after the lungs were treated for electron microscopical analysis. The lungs instilled with sepiolites increased their weight and tidal volume statistically significantly compared with the unexposed control. The numbers of lymphocytes and polymorphonuclear cells (PMN) in the bronchoalveolar lavage (BAL) fluid also increased compared with the control, indicating the sepiolite induced inflammation. The heat treated sepiolites, however, did not show any toxicological differences from the untreated sepiolites. Although sepiolite showed less change in fiber atomic % compositions ( sepiolite 500, Si 0.9%, p <0.01 ; sepiolite 700, Si 3.7%, p<0.05) than chrysotile (Si 9.7%, p<0.01), the durability of the fibers in the lungs could not be determined in this subchronic experiment.

Optimal Dual Pricing and Passenger Safety Level for Cruise Revenue Management

  • Cho, Seong-Cheol;Zhang, Mengfei
    • Journal of Navigation and Port Research
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    • v.41 no.2
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    • pp.63-70
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    • 2017
  • Despite the remarkable continual growth of the world cruise industry, studies have yet to be attempted on many revenue management problems in cruise operations. This paper suggests two schemes that can be easily applied to cruise revenue management: optimal dual pricing and passenger safety level. In optimal dual pricing, a pair of higher and lower prices is applied to cabin reservation through market segmentation. This scheme can be executed with a linear price-response function for the current unreserved cabins. A cruise line could benefit from this scheme to maximize reservation revenue while attaining full occupancy. The dual pricing scheme is also devised to produce only integer demands to suit real management practices. The life boat capacity is an additional service capacity unique to the cruise industry, catering to passengers' safety. The concept of passenger safety level is defined and computed for any passenger life boat capacity of a cruise ship. It can be used to evaluate the passenger safety of a cruise ship in operation, as well as to determine the number of life boat seats required for a new cruise ship. Hypothetical examples are used to illustrate the operation of these two schemes.

A Study on Evaluation Method of the HDA Test in Domestic Road Environment (국내도로 환경에서의 HDA 시험평가 방법에 관한 연구)

  • Bae, Geon Hwan;Kim, Bong Ju;Lee, Seon Bong
    • Journal of Auto-vehicle Safety Association
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    • v.11 no.4
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    • pp.39-49
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    • 2019
  • Autonomous vehicle is a car which drives itself without any human interaction. SAE provides technical definitions for autonomous and international standards for test evaluation. Accordingly, automobile industry is actively researching development and evaluation of various ADAS (Advanced Driver Assistance Systems), : representative technology of autonomous technology. Recently, ADAS is in the commercialization level such as ACC, LKAS, AEB, and HDA etc. And it also has issues about safety evaluation. The purpose of HDA in ADAS is reduced the driving load on highway. It has a function which can maintain lane keeping and control distance from forward vehicle. This function is evaluated to be useful for accident prevention. Therefore, this paper proposes the safety evaluation scenario of HDA, considering the domestic highway design criteria and the situation that may arise on the actual highway. We compared and analyzed the data acquired through simulation and actual vehicle test. And verified the reliability of the proposed safety evaluation scenario. The verified result is expected safety evaluation of HDA is possible even under the bad condition, which cannot be tested.

The Building for Safety Regulation DB of Urban Transit System Infrastructure used by Computer Design Tool (전산지원도구를 이용한 도시철도시설 안전기준 DB구축 연구)

  • Lee, Woo-Dong;Shin, Jeong-Ryul;Ahn, Tai-Ki
    • Proceedings of the KSR Conference
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    • 2006.11b
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    • pp.786-790
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    • 2006
  • Urban rail transit offers target performance and function because various lower part system such as rolling-stock, signal, power and trackis consisted as complex. In order to function properly an urban rail transit which is complicated system to work as safety and reliability, System must secure safety with structure, design, manufacture, install and verification and it is important to establish a safety standard follows it procedures, establish what step all it is important to operate. Safety standard of urban transit infrastructure is minimum standard necessary to secure safety of signal, power and track. Urban rail transit standard business leads to make many requirements. Recently, many types of equipment have applied to manage requirements and standards for system efficiently in part of universal, airline and car accordingly applied equipments use to manage a pursuit(Trace) between standard of system. Especially importance of management is emphasized more become more. Importance of standard management which usesa computing support tool recently in transit filed is embossed and is predicted to be more such forward. Therefore we propose the effective method of management with infrastructure system by constructed data-base system.

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Optimum Safety Indices Based On Expected Total Cost Minimization (총기대비용 최소화원칙에 의한 최적신뢰성지수)

  • 이증빈;신형우;장석모
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1993.10a
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    • pp.216-223
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    • 1993
  • The safety factors of current standard code are considered to be not appropriate compared to design and construction practices, even this safety factors are not determined from probabilistic study but merely from experiences and practices. This study pripose the optimum safety indices based on expected total cost minimization using only three parameters, which are the level of the failure cost to the initial cost by improvement in safety, and the order of the initial cost function.

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