• 제목/요약/키워드: Quantitative Assessments

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A Progress-based Expert System for Quantitative Assessments of Project Delay

  • Yoo, Wi Sung
    • Architectural research
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    • 제10권1호
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    • pp.41-48
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    • 2008
  • Construction projects have frequently exceeded their schedule despite reliable estimates at the start of a project. This problem was attributed to unpredictable causes at the beginning and to shortage of proper tools to accurately predict project completion date. To supplement this difficulty, project managers need a comprehensive system that can be employed to monitor the progress of an ongoing project and to evaluate potential delay for achieving the goal on time. This paper proposed a progressive-based expert system for quantitative assessments of project delay at the early stages of the execution. Furthermore, the system is used to inspect the change of the uncertainty on completion date and its magnitude. The proposed expert system is helpful for furnishing project managers a warning signal as a project is going behind schedule and for tracking the changed uncertainty at a desired confidence level. The main objectives of this paper are to offer a new system to overcome the difficulties of conventional forecasting tools and to apply a construction project into the system to illustrate its effectiveness. This paper focuses on construction phase of project development and is intended for the use by project managers.

정량적 위험성 평가에 의한 안전관리 투자의 비용-편익분석 (Cost-Benefit Analysis for Safety Management Cost using Quantitative Risk Analysis)

  • 장서일;조지훈;김태옥
    • 대한안전경영과학회지
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    • 제4권4호
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    • pp.15-26
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    • 2002
  • The quantitative evaluation method of the safety management cost was suggested to prevent a gas accident as a major industrial accident. In a gas governor station, process risk assessments such as the fault tree analysis(FTA) and the consequence analysis were performed. Based on process risk assessments, potential accident costs were estimated and the cost-benefit analysis(CBA) was performed. From the cost-benefit analysis for five classification items of safety management cost, the order of the cost/benefit ratio was estimated.

Microbial Modeling in Quantitative Risk Assessment for the Hazard Analysis and Critical Control Point (HACCP) System: A Review

  • Min, Sea-Cheol;Choi, Young-Jin
    • Food Science and Biotechnology
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    • 제18권2호
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    • pp.279-293
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    • 2009
  • Quantitative risk assessments are related to implementing hazard analysis and critical control points (HACCP) by its potential involvement in identifying critical control points (CCPs), validating critical limits at a CCP, enabling rational designs of new processes, and products to meet required level of safety, and evaluating processing operations for verification procedures. The quantitative risk assessment is becoming a standard research tool which provides useful predictions and analyses on microbial risks and, thus, a valuable aid in implementing a HACCP system. This paper provides a review of microbial modeling in quantitative risk assessments, which can be applied to HACCP systems.

Case Studies of Risk Assessment in Analyzing Risks Associated with MSDS

  • Kim, Woo Jin;Jeong, Byung Yong
    • 대한인간공학회지
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    • 제32권1호
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    • pp.153-158
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    • 2013
  • Objective: This study aims to suggest different approaches in analyzing risks associated with musculoskeletal disorders (MSDS) for risk assessment. Background: Upon concluding that the changes in the industrial environments have made it hard to regulate diverse risk factors, the government has implemented a policy for risk assessment. Method: This study has proposed a method, creating programs using Excel that perform qualitative or quantitative analysis, for evaluating risk factors in risk assessments and has applied this in manufacture and service industries. Results: To verify the validity of the developed program, risk assessment has been performed on restaurant chefs as an example. For quantitative evaluation, the study has suggested approaches using the results for REBA evaluation and the analysis report on the work scenes of a fitting-shop in a shipbuilding industry. Application: Constructing and adapting a system using Excel in evaluating risk factors for risk assessments as this study suggests, is expected to contribute to revitalizing risk assessments.

농촌마을종합개발사업 중간 점검을 위한 평가지표 적용사례 (Development of An Evaluation System for the Interim Check of Integrated Rural Village Development Project)

  • 한경수;김기현;전택기;엄대호;최윤상
    • 농촌계획
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    • 제13권2호
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    • pp.121-132
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    • 2007
  • In this study, We developed an evaluation system for the interim check of Integrated Rural Village Development Project and analyzed its applicability to an actual evaluation process through a pilot evaluation on regions selected. The evaluation system consists of documentary assessments(30%) and field inspections(70%). The documentary assessments are quantitative assessments on check-lists reports by self-evaluation prepared by local governments. The field inspections are qualitative assessments by evaluation teams. Sixteen evaluation indices were developed for documentary assessments and seven criteria were designed for field inspections. For a pilot evaluation, one region in each province excluding Jeju Do, eight regions was selected and the field inspections due to circumstances was proceeded in two regions. The results of documentary assessments indicate that most of regions are evaluated low in project performance attributable to the delay in security for sites. In the field inspections, it appears that most of the regions evaluated high at the documentary assessments got a high point from them. They also show that coordination of action plans, rather than quantitative achievements, is a base determining success of the projects.

Quantitative Risk Assessment

  • Ryzin John Van
    • 대한예방의학회:학술대회논문집
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    • 대한예방의학회 1994년도 교수 연수회(환경)
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    • pp.469-475
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    • 1994
  • This paper presents a brief survey of current methodology available for quantitative risk assessment of environmental carcinogens. Four current models for low-dose extrapolation are reviewed. Current problems and controversies and possible options in doing quantitative risk assessments based on chronic animal studies are discussed.

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초고속 통신망에서 비디오의 주관적 품질 평가에 관한 연구 (The research on subjective video quality assessments of Broadband Networks)

  • 강명화;강진석;최연성;김장형
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2001년도 춘계종합학술대회
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    • pp.279-284
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    • 2001
  • 멀티미디어와 정보통신의 발달과 더불어 정보통신 사업의 모든 영역에서 경쟁을 맞게 됨에 따라 과거 양적인 팽창에 주력하던 시대에서 이제는 질적인 향상에 주력해야되는 시대가 도래하였다. 본 연구에서는 갈수록 수요가 급증하고 있는 실시간 대화형 멀티미디어 서비스의 비디오에 대한 품질 평가를 수행하고자 한다. 그리고 ITU-T를 비롯한 외국 관련 기관과 국내에서의 멀티미디어 품질평가 활동을 분석하며, 초고속 통신망에서 비디오에 대한 전송 품질의 주관적 평가를 실시하고 우리에게 맞는 새로운 주관적 품질 평가 기준을 제시하고자 한다.

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ALVIM Phantom을 이용한 화질관리 (Image Quality Management Using ALVIM Phantom)

  • 임득춘;동경래;박용순;김창복;류영환
    • 대한디지털의료영상학회논문지
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    • 제11권2호
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    • pp.63-68
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    • 2009
  • Among various physical or subjective assessments of the quality of X-ray images, physical assessments can be quantitative but they are eventually judged by the view of observers thus subjective assessments including the aspect of observers are required. The changes in the ability to detect lesions caused by changes in the thickness of acrylic plates were tested with the ROC interpretation method that has taken into consideration, all the features of physical assessments as well as observers' ability to observe and mental stages and even surrounding environments using an Alvim phantom and the result indicated that as the thickness of acrylic plates increased, the amount of noises occurred increased compared to signals and thus the ability to detect signals as well as the sensitivity that is an ability to signals accurately and the ability to distinguish noises from signals thus it is considered that more efforts of radiologic technologists will be required to detect small lesions of fat patients with diagnostic X-ray generating apparatus.

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Principles of Chemical Risk Assessment: The ATSDR Perspective

  • Johnson Barry L.
    • 대한예방의학회:학술대회논문집
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    • 대한예방의학회 1994년도 교수 연수회(환경)
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    • pp.405-411
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    • 1994
  • Hazardous wastes released into the general environment are of concern to the public and to public health authorities. In response to this concern, the Comprehensive Environmental Response, Compensation, and Liability Act, as amended (commonly called Superfund), was enacted in 1980 to provide a framework for environmental, public health, and legal actions concerning uncontrolled releases of hazardous substances. The Agency for Toxic Substances and Disease Registry (ATSDR) was created by Superfund to address the public health issues of hazardous wastes in the community environment. Two key Agency programs, Public Health Assessments and Toxicological Profiles, are designed to assess the risk to human health of exposures to hazardous substances that migrate from waste sites or through emergency releases (e.g., chemical spills). The Agency's public health assessment is a structured process that permits ATSDR to identify which waste sites or other point sources require traditional public health actions (e.g.. human exposure studies, health studies, registries, health surveillance, health advisories). The ATSDR qualitative public health assessment complements the U.S. Environmental Protection Agency's quantitative risk assessment. For Superfund purposes, both assessments are sitespecific. ATSDR's toxicological profiles are prepared for priority hazardous substances found most frequently at Superfund sites. Each profile presents the current toxicologic and human health effects information about the substance being profiled. Each profile also contains Minimal Risk Levels (MRLs), a type of risk assessment value. This paper covers ATSDR's experience in conducting public health assessments and developing MRLs, and it relates this experience to recommendations on how to improve chemical risk assessments.

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해수유동모델 검증을 위한 오차평가방법 비교 연구 (Skill Assessments for Evaluating the Performance of the Hydrodynamic Model)

  • 김태윤;윤한삼
    • 한국해양환경ㆍ에너지학회지
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    • 제14권2호
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    • pp.107-113
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    • 2011
  • 해수유동모델의 검증 및 평가를 위해 적용되는 또는 적용가능한 10종류의 모델 오차평가방법 - 네가지의 정량적 평가방법(절대평균오차, 평균제곱근 오차, 상대적 절대평균오차, 백분율모델오차)과 여섯가지의 정성적 평가방법(상관계수, 신뢰지수, 일치지수, 모델효율성, 비용함수, 잔여량계수) - 을 소개하고, 실제 조위, 유속, 염분관측치와 3차원 곡선형 모델(CH3D)에서 구해진 플로리다 하구에서의 수치해에 이들 모델 오차평가방법들을 적용하였다. 조위 및 유속평가시 절대평균오차, 평균제곱근 오차, 상대적 절대평균오차, 상관계수, 일치지수, 모델효율성, 비용함수, 잔여량계수 등이 적합하였다. 그리고 염분평가시 절대평균오차, 평균제곱근 오차, 상대적 절대평균오차, 백분율모델오차, 상관계수, 신뢰지수, 비용함수, 잔여량계수 등의 사용이 타당하였다. 정량/정성적 평가방법들이 서로 유사한 평가경향을 보여 줌으로써, 상호간의 신뢰성도 보여 주었다. 다양한 모델 오차평가방법을 통하여 계산된 평가값을 토대로, 본 연구에서는 조위, 유속, 염분이 잘 재현된 해수유동모델의 평가범위를 제시하였다. 조위의 경우 상대적 절대평균 오차는 10%이내, 상관계수는 0.95이상, 일치지수는 0.98이상, 모델효율성은 0.93이상, 비용함수는 0.21이내이며, 유속의 경우 상대적 절대평균오차는 20%이내, 상관계수는 0.7이상, 일치지수는 0.8이상, 모델효율성은 0.5이상, 비용 함수는 0.5이내이며, 염분의 경우 상대적 절대평균오차와 백분율모델오차는 10%이내, 상관계수는 0.9이상, 신뢰지수는 1.15이내, 비용함수는 0.1이내 이다.