• Title, Summary, Keyword: risk assessment

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Dynamic risk assessment of water inrush in tunnelling and software development

  • Li, L.P.;Lei, T.;Li, S.C.;Xu, Z.H.;Xue, Y.G.;Shi, S.S.
    • Geomechanics and Engineering
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    • v.9 no.1
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    • pp.57-81
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    • 2015
  • Water inrush and mud outburst always restricts the tunnel constructions in mountain area, which becomes a major geological barrier against the development of underground engineering. In view of the complex disaster-causing mechanism and difficult quantitative predictions of water inrush and mud outburst, several theoretical methods are adopted to realize dynamic assessment of water inrush in the progressive process of tunnel construction. Concerning both the geological condition and construction situation, eleven risk factors are quantitatively described and an assessment system is developed to evaluate the water inrush risk. In the static assessment, the weights of eight risk factors about the geological condition are determined using Analytic Hierarchy Process (AHP). Each factor is scored by experts and the synthesis scores are weighted. The risk level is ultimately determined based on the scoring outcome which is derived from the sum of products of weights and comprehensive scores. In the secondary assessment, the eight risk factors in static assessment and three factors about construction situation are quantitatively analyzed using fuzzy evaluation method. Subordinate levels and weight of factors are prepared and then used to calculate the comprehensive subordinate degree and risk level. In the dynamic assessment, the classical field of the eleven risk factors is normalized by using the extension evaluation method. From the input of the matter-element, weights of risk factors are determined and correlation analysis is carried out to determine the risk level. This system has been applied to the dynamic assessment of water inrush during construction of the Yuanliangshan tunnel of Yuhuai Railway. The assessment results are consistent with the actual excavation, which verifies the rationality and feasibility of the software. The developed system is believed capable to be back-up and applied for risk assessment of water inrush in the underground engineering construction.

Risk identification, assessment and monitoring design of high cutting loess slope in heavy haul railway

  • Zhang, Qian;Gao, Yang;Zhang, Hai-xia;Xu, Fei;Li, Feng
    • Structural Monitoring and Maintenance
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    • v.5 no.1
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    • pp.67-78
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    • 2018
  • The stability of cutting slope influences the safety of railway operation, and how to identify the stability of the slope quickly and determine the rational monitoring plan is a pressing problem at present. In this study, the attribute recognition model of risk assessment for high cutting slope stability in the heavy haul railway is established based on attribute mathematics theory, followed by the consequent monitoring scheme design. Firstly, based on comprehensive analysis on the risk factors of heavy haul railway loess slope, collapsibility, tectonic feature, slope shape, rainfall, vegetation conditions, train speed are selected as the indexes of the risk assessment, and the grading criteria of each index is established. Meanwhile, the weights of the assessment indexes are determined by AHP judgment matrix. Secondly, The attribute measurement functions are given to compute attribute measurement of single index and synthetic attribute, and the attribute recognition model was used to assess the risk of a typical heavy haul railway loess slope, Finally, according to the risk assessment results, the monitoring content and method of this loess slope were determined to avoid geological disasters and ensure the security of the railway infrastructure. This attribute identification- risk assessment- monitoring design mode could provide an effective way for the risk assessment and control of heavy haul railway in the loess plateau.

Study on Theoretical Models of Regional Humanity Lung Cancer Hazards Assessment

  • Zhang, Chuan;Gao, Xing
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.5
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    • pp.1759-1764
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    • 2015
  • Purpose: To establish the concept of lung cancer hazard assessment theoretical models, evaluating the degree of lung cancer risk of Beijing for regional population lung cancer hazard assessment to provide a basis for technical support. Materials and Methods: ISO standards were used to classify stratified analysis for the entire population, life cycle, processes and socioeconomic management. Associated risk factors were evaluated as lung cancer hazard risk assessment first class indicators. Study design: Using the above materials, indicators were given the weight coefficients, building lung cancer risk assessment theoretical models. Regional data for Beijing were entered into the theoretical model to calculate the parameters of each indicator and evaluate the degree of local lung cancer risk. Results: Adopting the concept of lung cancer hazard assessment and theoretical models for regional populations, we established a lung cancer hazard risk assessment system, including 2 first indicators, 8 secondary indicators and 18 third indicators. All indicators were given weight coefficients and used as information sources. Score of hazard for lung cancer was 84.4 in Beijing. Conclusions: Comprehensively and systematically building a lung cancer risk assessment theoretical model for regional populations in conceivable, evaluating the degree of lung cancer risk of Beijing, providing technical support and scientific basis for interventions for prevention.

A Study on the Perception Level of Health and Safety among the Participants for Optimization of Risk Assessment in Construction Industry (건설업 위험성 평가 최적화를 위한 운영 주체간 안전보건 인식도 조사 연구)

  • Paek, Chung-Hyeun;Cho, Ur-Ryong
    • Journal of the Korea Safety Management & Science
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    • v.17 no.3
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    • pp.23-32
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    • 2015
  • Recently, the Ministry of Labour, published clause 2 of Article 41 (Risk Assessment) of the Act "Industrial Safety and Health" dated 12 June 2013 in connection with continuous increase of accidents at construction sites in order to prevent accidents in industrial safety and health in new construction in accordance with the risk assessment on construction projects are realized after March 13, 2014. In this paper, positive method of calculating risk discussed by performing research the awareness of general contractors and sub-contractors with presenting risky situation is considered. The purpose will be a positive method of calculating risk and would be a sufficient base and give a positive direction in the development of new systems currently working in the construction and risk assessment which consider the characteristics of sufficient risk assessment system for future research.

The Adoption of Risk Assessment Methodology in Exposure Assessment (근로자 노출평가제도 내 위험성평가 방법론의 적용)

  • Kim, Seung Won;Choi, Sangjun;Phee, Young Gyu;Kim, Kab Bae
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.25 no.4
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    • pp.482-492
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    • 2015
  • Objectives: Exposure Assessment for workplace hazards where the exposure level is below occupational exposure limits(OELs) has been performed without considering either the degrees of risk or exposure levels and has failed to lead to intervention in many cases. The objective of this study was to suggest and test an application framework for risk assessment methodology under the current exposure assessment system in Korea. Materials: First, we investigated the exposure assessment systems in Korea and other countries. To adopt some risk assessment techniques, we also analyzed risk assessment systems and compared them to exposure assessment systems. A few suggestions were made. We held a public hearing during an industrial hygiene conference and took surveys using a questionnaire. Results: The first suggestion was to implement the risk assessment and exposure assessment through a "one-stop" system. In that case, one expected question would be who has been doing the jobs so far. In most cases, industrial hygiene consulting services or laboratories have been performing exposure assessment for business owners. Business owners are required to perform risk assessment. As two different groups of people will be required to implement two things in a one-stop system, they need to share information. As an information vehicle to share information, commonly filed survey checklists were suggested. The second suggestion was to categorize exposure level into four groups instead of the current binary divisions based on OELs. In the risk assessment system, exposure level is divided into four groups utilizing the cut-points of 10%, 50%, and 100% of OELs. The same schema can be adopted in the exposure assessment system and different levels of requirements can be assigned for each group. The third suggestion was regarding the regulation system. To provide the suggestions some thrust toward being implemented in the field, changes should be made in the legal system. Two different types of new exposure assessment result reporting forms were suggested. Some investigations such as an ergonomic survey are officially accepted as risk assessment under the current legal system. A few items were suggested to be included in the exposure assessment result reporting to be accepted as risk assessment. A pilot study in two small factories was performed and pointed out the strengths and weakness of our suggestions. Conclusions: Discussions and studies on the improvement of the exposure assessment system have been held for decades and no tangible changes have yet been made. We hope this result can help realize healthy lives for workers in Korea.

A Study on the Health Risk Assessment of Volatile Organic Compounds in a Petrochemical Complex (석유화학단지의 휘발성 유기화합물로 인한 인체 위해도 평가에 관한 연구)

  • 이진홍;김윤신;류영태;유인석
    • Journal of Korean Society for Atmospheric Environment
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    • v.13 no.4
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    • pp.257-267
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    • 1997
  • This study focuses on the health risk assessment of airborne volatile organic compounds (VOCs) in a petrochemical complex, with several emphases on a risk assessment method. The first emphasis is on the importance of hazard identification to determine the likely carcinogenic potential of a VOC. Without considering this type of information, a direct comparison of the carcinogenic risks of two pollutants is meaningless. Therefore, wer suggest that this type of information be prepared and be listed with the estimate of cancer risk in parallel. The second emphasis is on the selection of a better dose-response model to estimate unit risk or cancer potency factor of a carcinogenic VOC. Finally, probilistic risk assessment method is discussed and recommended to use within a comparison of conventional point-estimate method. A health risk assessment has also been carried out. For non-carcinogenic risk, even the highest hazard index for carbon tetrachloride is estimated to be less than 1 with the other VOCs less than 0.03. However, the lifetime cancer risk from the inhalation of airborne VOCs is estimated to be about $2.6 \times 10^{-4}$ which is higher than the risk standard of $10^{-6}$ or even $10^{-5}$. Therefore, the investigation into domestic petrochemical complexes should be strengthened to obtain more fine long-term airborne VOC data.

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Prediction of Maintenance Period of Equipment Through Risk Assessment of Thermal Power Plants (화력발전설비 위험도 평가를 통한 기기별 정비주기 예측)

  • Song, Gee Wook;Kim, Bum Shin;Choi, Woo Song;Park, Myung Soo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.37 no.10
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    • pp.1291-1296
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    • 2013
  • Risk-based inspection (RBI) is a well-known method that is used to optimize inspection activities based on risk analysis in order to identify the high-risk components of major facilities such as power plants. RBI, when implemented and maintained properly, improves plant reliability and safety while reducing unplanned outages and repair costs. Risk is given by the product of the probability of failure (POF) and the consequence of failure (COF). A semi-quantitative method is generally used for risk assessment. Semi-quantitative risk assessment complements the low accuracy of qualitative risk assessment and the high expense and long calculation time of quantitative risk assessment. The first step of RBI is to identify important failure modes and causes in the equipment. Once these are defined, the POF and COF can be assessed for each failure. During POF and COF assessment, an effective inspection method and range can be easily found. In this paper, the calculation of the POF is improved for accurate risk assessment. A modified semi-quantitative risk assessment was carried out for boiler facilities of thermal power plants, and the next maintenance schedules for the equipment were decided.

A Study on Fire Risk Assessment by the Consideration of Individual Evacuating Path Line (개인별 대피경로를 고려한 화재위험성 평가에 관한 연구)

  • Rie, Dong-Ho
    • Journal of the Korean Society of Safety
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    • v.22 no.4
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    • pp.1-6
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    • 2007
  • In this study, we provided an index for the quantitative and systematic performance based fire risk assessment. A complex cinema was adopted for the fire scenario and the fire simulation was carried out by using FDS. Also evacuation time was calculated by using SIMULEX. We obtained a big different fire risk assessment result by the focus on the between space basis and the time basis. As a result of this study, performance based fire risk assessment should be performed on the basis of individual evacuee's path line.

Considerations for Quantitative Risk Assessment of Landslides using GIS (GIS기반 산사태재해의 정량적 피해 산정을 위한 고려사항 분석)

  • Kim, Jung-Ok;Kim, Ji-Young;Kim, Hyo-Joong;Kim, Yong-Il
    • 한국방재학회:학술대회논문집
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    • pp.645-648
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    • 2008
  • This study provides considerations for quantitative risk assessment of landslide on GIS technology. It shows how the landslide possibility analysis is linked by GIS modeling to provide loss estimation tools for landslide hazards in support of socio-economic loss reduction efforts. Those risk assessment results can deliver factual damage situation prediction to policy making for the landslide damage mitigation.

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Health Risk Assessment on Environmental Pollutants (환경오염물질의 건강위해성 평가)

  • 신동천
    • Journal of environmental and Sanitary engineering
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    • v.8 no.2
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    • pp.11-24
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    • 1993
  • Methodology for health risk assessment has been developed by governmental agencies and research institutions in the United States concerning environmental and industrial health such as Environmental Protection Agency, Pood and Drug Administration, and Occupational Safety and Health Administration. The basic concept, process, and scientific rational of the health risk assessment are discussed in order to introduce this field of research for future application to risk assessment and management in Korea. As environmental criteria for most of the environmental carcinogens and nonfarcinogens are set based on the quantitative risk assessment, this quantitative methodology should be emphasized and studied in Korean situation.

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