• Title/Summary/Keyword: Risk Factor Assessment

Search Result 606, Processing Time 0.024 seconds

Reliability and risk assessment for rainfall-induced slope failure in spatially variable soils

  • Zhao, Liuyuan;Huang, Yu;Xiong, Min;Ye, Guanbao
    • Geomechanics and Engineering
    • /
    • v.22 no.3
    • /
    • pp.207-217
    • /
    • 2020
  • Slope reliability analysis and risk assessment for spatially variable soils under rainfall infiltration are important subjects but they have not been well addressed. This lack of study may in part be due to the multiple and diverse evaluation indexes and the low computational efficiency of Monte-Carlo simulations. To remedy this, this paper proposes a highly efficient computational method for investigating random field problems for slopes. First, the probability density evolution method (PDEM) is introduced. This method has high computational efficiency and does not need the tens of thousands of numerical simulation samples required by other methods. Second, the influence of rainfall on slope reliability is investigated, where the reliability is calculated from based on the safety factor curves during the rainfall. Finally, the uncertainty of the sliding mass for the slope random field problem is analyzed. Slope failure consequences are considered to be directly correlated with the sliding mass. Calculations showed that the mass that slides is smaller than the potential sliding mass (shallow surface sliding in rainfall). Sliding mass-based risk assessment is both needed and feasible for engineered slope design. The efficient PDEM is recommended for problems requiring lengthy calculations such as random field problems coupled with rainfall infiltration.

Risk Assessment of Soil Erosion in Gyeongju Using RUSLE Method (RUSLE 기법을 이용한 경주지역의 토양침식 위험도 평가)

  • Oh, Jeong-Hak;You, Ju-Han;Kim, Kyung-Tae;Lee, Woo-Sung
    • Journal of Environmental Impact Assessment
    • /
    • v.20 no.3
    • /
    • pp.313-324
    • /
    • 2011
  • The purpose of this study is to present the raw data for establishing the plan of top soil conservation in soil environment and preventing the soil loss by establishing the potential amount of soil loss using RUSLE. The results are as follows. To apply the RUSLE model, we calculated the potential amount of soil loss by using 5 factors; rainfall erosion factor(R), topographical factor(LS), soil erosion factor(K), land cover factor(C) and erosion control factor(P). The assessment map of soil loss was drawn up by classifying 5 grades. According to the soil loss estimation by the RUSLE, it showed that approximately 83.9% of the study area had relatively lower possibility of soil loss which was the 1 ton/ha in annual soil loss. Whereas, the 7.0% of the study area was defined as high risk area which was the 10 ton/ha in annual. Therefore, this area was needed that there was environment-friendly construction of farm land, improvement of cultivation environment and so forth. In future, if we will analyze the amount of soil loss of Gyeongju national park and Hyeongsan river watershed, we will offer the help to establishing the conservation plan of soil environment in Gyeongsangbuk-do.

Analysis of Operation System Establishment Cases for Efficient use of Risk Assessment at Construction Sites - H Focusing on Construction Company Cases (건설현장의 위험성평가 효율적 활용을 위한 운영 시스템 구축사례 분석 - H 건설사 사례중심으로)

  • Jae-Bung Lee
    • Journal of the Society of Disaster Information
    • /
    • v.18 no.4
    • /
    • pp.828-838
    • /
    • 2022
  • Purpose: Through the establishment of a computerized system of risk assessment, the purpose is to analyze the case of whether the co-workers who are subject to the risk assessment at the construction site can easily fill it out and expect disaster reduction through efficient risk assessment activities. Method: By providing the risk factors and safety measures for the work by selecting the type of work, the risk estimation and the establishment of countermeasures can be made, and a system has been established to enable practical disaster prevention activities by presenting disaster cases for the work. Result: Through the analysis of the change in the scaled disaster rate for the years following the on-site application after the establishment of the risk assessment computer system of H Construction Company, it was confirmed that the scaled disaster rate of the domestic construction industry increased, while the conversion disaster rate of H Construction Company decreased. Conclusion: Through the computational systemization of risk assessments, workers in the field can easily access the risk assessment, evaluate the risk factors of the process and establish risk prevention measures, and it has been analyzed that there is an impact on the reduction of the disaster rate during the operational analysis period.

An Analysis on the Relative Importance of the Risk Factors for the Marine Traffic Environment using Analytic Hierarchy Process

  • Lee, Hong-Hoon;Kim, Chol-Seong
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.19 no.3
    • /
    • pp.257-263
    • /
    • 2013
  • The classification of risk factors and the identification of risk acceptance criteria are core works to assess risk levels with high enough confidential level in the field of marine traffic environment. In the previous study work, the twenty kinds of risk factors and its assessment criteria for the domestic marine traffic environment were proposed. In this paper, with these previous studying results, the relative importance of the risk factors were analyzed by questionnaire survey of marine traffic experts using the analytic hierarchy process. The analysis results showed that the relative importance of the visibility restriction is the highest among the twenty kinds of risk factors, and the relative importance of the traffic condition is the highest among the five kinds of risk categories. As results from analysis, it is expected that the approaching method on the relative importance is to be one of basic techniques for the development of risk assessment models in the domestic marine traffic environment.

Nutrition Assessment of Older Subjects in a Health Care Center by MNA (Mini Nutritional Assessment) (MNA (Mini Nutritional Assessment)를 이용한 건강증진센터 내원 노인의 영양상태 판정)

  • Lee, Hye-Ok;Lee, Jeong-Sook;Shin, Ji-Won;Lee, Geum-Ju
    • Journal of the Korean Dietetic Association
    • /
    • v.16 no.2
    • /
    • pp.122-132
    • /
    • 2010
  • Elderly people comprise an increasing proportion of the population, and nutritional impairments may contribute to health problems among this group. This study was conducted to evaluate the nutritional status by Mini-Nutritional Assessment (MNA) and to identify relationships among anthropometric measurements, biochemical indicators, bone Mineral Density (BMD) and MNA results among older adults (${\geq}$65 yrs, n=98, 66.7${\pm}$2.5 yrs; M=52, F=46, BMI 24.5${\pm}$2.8 $kg/m^2$) at a Health Care Center. A dietitian administered MNA and collected anthropometric measurements (weight, height, waist circumference), biochemical indicators (albumin, hemoglobin, hematocrit, TLC, glucose, lipids) and the BMD (spine, femur, F=46). Subjects were grouped into a normal nutrition group (0~2 risk factors of malnutrition) and a high risk of malnutrition group (>=3 risk factors of malnutrition) based on their risk factor status for malnutrition. The risk factors for malnutrition include age ${\geq}$65 years, PIBW <90%, albumin <3.5 g/dl, TLC <1,500%, Hgb <14 g/dl (men), Hgb <10 g/dl (women), loss of appetite and weight loss 1~3 kg/last 3 months. In addition, subjects were grouped into a normal, osteopenia and osteoporosis group by BMD. We found that 12% of the subjects were at risk of malnutrition (MNA score, 21.4${\pm}$2.1) and that 88% were well nourished (27.3${\pm}$1.5) according to the MNA. Full-MNA scores were positively and significantly (p<0.05) associated with BMI, mid-arm circumference (MAC), calf circumference (CC), albumin and hemoglobin, respectively. The full-MNA score of the high risk of malnutrition group (23.0${\pm}$3.8) was lower than that of the normal nutrition group (27.0${\pm}$2.1) (p<0.05). In addition, the Full-MNA score was negatively associated with the risk factor of malnutrition (r=-0.35, p=0.0004). We found that 39.1% of the subjects had osteoporosis, 45.7% had osteopenia and 15.2% were normal according to their BMD. The MNA score of osteoporosis group (24.58${\pm}$3.3) was lower than that of the normal (27.4${\pm}$1.1) and osteopenia group (26.9${\pm}$1.5) (p<0.05). These results suggested that MNA can be useful as a nutritional screening tool of older adults in Health Care Centers.

Analysis of Installation Status and Application of GIS for Preliminary Risk Assessment of Underground Storage Tanks in Chuncheon City (춘천시의 지하 저장 탱크의 예비적 위해성 평가를 위한 설치 현황 분석 및 지리정보시스템의 적용)

  • Kim, Joon-Hyun;Han, Young-Han;Lee, Jong-Chun;Kwon, Young-Sung;Lee, Kwang-Yeon
    • Journal of Industrial Technology
    • /
    • v.22 no.A
    • /
    • pp.127-135
    • /
    • 2002
  • In this study, the preliminary risk assessment for the underground storage tanks(UST) in Chunchon city was implemented using the geographical information system(GIS). The estimation variables, such as the installation year, storage capacity, the distances from streams, and from groundwater pumping wells, were selected to estimate the relative risk levels. The weighting factors were given to all the estimation variables. Cumulative scores were induced by the combination of all the scores of the corresponding variables using the buffering technique and the overlay analysis in ArcView. Using the these process, the relative risk level of each UST was estimated. Some sites in this study are simplified and reduced because the number of useable data are limited or too enormous. Thus the selection of the comprehensive estimation variables and the proper weighting values are required for the future study. The methodology in this study could be served not only for the preliminary risk assessment of UST but also for the selection of the proper location of new and old UST. And, it can be used for the effective management system of UST.

  • PDF

Pyrolytic Formation of Benzo[a]pyrene in Foods During Heating and Cancer Risk Assessment in Koreans (식품가열에 따른 Benzo[a]pyrene 생성 및 한국인의 발암 위해성 평가)

  • 최옥경;이병무
    • Journal of Food Hygiene and Safety
    • /
    • v.9 no.3
    • /
    • pp.133-139
    • /
    • 1994
  • The pyrolytic formation of benzo[a]pyrene during the cooking procedure was analysed in beef, pork, pacific saury, rice, and soybean by HPLC. In raw foods, benzo[a]pyrene (B[a]P) was not detected or negligible, but it was increasingly formed when foods were boiled (0.010~0.037 ppb) and more dramatically during broiling (0.302~0.851 ppb) in a time dependent manner. Human daily intake of B[a]P in Koreans and cancer risk assessment were estimated based on food consumption per capita and carcinogenic potency of B[a]P. When cooked foods were consumed for entire life time, cancer risk was estimated to bo 1.77$\times$10-6>1.65$\times$10-7>1.32$\times$10-8 by the order of broiled, boiled, and raw foods consumption. These data suggest that broiled foods produce more benzo[a]pyrene than water boiled foods. Thus cooking procedure is an important factor for the formation of carcinogens and needs to bo modified to reduce cancer risk for man.

  • PDF

A Study on the Hazard Factor and Safety Management at Transmission Line During Live Line Works (송전선로 직접활선공법의 위험요인과 안전대책에 관한 연구)

  • Choi, Seung-Dong;Kang, Kyong-Sik
    • Journal of the Korea Safety Management & Science
    • /
    • v.8 no.3
    • /
    • pp.51-66
    • /
    • 2006
  • This study was attempted to analyze risk factors and suggest accident prevention in live line works for power transmission lines to be developed and applied in Korea. Safety problem cannot but occur at development of live line works and application to the field. With respect to this, problems likely to occur in the field among works adopting methods of works including live line works for power transmission lines were investigated and analyzed through documentary survey and risk assessment method. The results are summarized as follows. A risk assessment method model was suggested. This method enables scientific and systematic development of safety control. That is, the owner may autonomously induce safety control and build risk assessment database by work process to use them as best training data for workers. Also, in the field, it may induce all workers to participate in safety program and secure safety by making workers seek for safety working method under smooth flow from looking at risk factors to accident prevention activities. It is deemed that this humble study will prevent both accident and injury likely to occur in live line works for power transmission lines.

Validation of the Short Form Bobath Memorial Hospital Fall Risk Assessment Scale at a Specialized Geriatric Hospital in Korea (단축형 노인 낙상위험 사정도구의 타당도)

  • Sohng, Kyeong-Yae;Park, Mi Hwa;Chaung, Seung Kyo;Park, Hye Ja
    • Journal of Korean Public Health Nursing
    • /
    • v.28 no.3
    • /
    • pp.495-508
    • /
    • 2014
  • Purpose: This study was conducted in order to evaluate the reliability, validity, sensitivity, and specificity of the Short Form of Bobath Memorial Hospital Fall Risk Assessment Scale (BMFRAS-SF). Methods: A validation study was conducted on 207 elderly patients aged over 65 who were admitted to Bobath Memorial Hospital. Fall risk scores of BMFRAS, composed of eight subscales (age, fall history, physical activity, consciousness level, communication, fall risk factors, underlying disease, and medications) were assessed from the electronic medical record. BMFRAS-SF was derived from eight subscales of the BMFRAS representing the significance between fallers and non-fallers (fall history, physical activity, fall risk factors, underlying disease, and medications). Internal consistency reliability and interrater reliability were assessed by Cronbach's alpha and kappa coefficient. Validity was assessed by Spearman correlation analysis, factor analysis. Sensitivity, specificity, positive predictive and negative predictive values, and a receiver-operating characteristic curve (ROC) were generated. Results: Fallers had significantly higher risk scores than non-fallers in fall history, physical activity, fall risk factors, underlying disease, and medication scales. The BMFRAS-SF demonstrated acceptable Cronbach's alpha (.706) and kappa coefficients of .95. The BMFRAS-SF subscales showed good convergent validity and construct validity. The BMFRAS-SF presented good sensitivity(86.7%), specificity(67.9%), positive predictive value(42.9%) and good negative predictive value(94.8%) at a cut-off score of 5. Areas under the ROC curves were .860 for the BMFRAS and .861 for the BMFRAS-SF. Conclusion: The BMFRAS-SF was proved to be reliable and valid. It could be used for time-saving assessment and evaluation of the high risks for falls in clinical practice settings.

The effect of a risk factor on quantitative risk assessment in railway tunnel (철도터널에서 위험인자가 정량적 위험도 평가에 미치는 영향)

  • Yoo, Ji-Oh;Kim, Jin-Su;Rie, Dong-Ho;Shin, Hyun-Jun
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.17 no.2
    • /
    • pp.117-125
    • /
    • 2015
  • Quantitative risk assessment (QRA) of railway is to create a variety of scenario and to quantify the degree of risk by a result of the product of accident frequency and accident. Quantitative risk Assessment is affected by various factors such as tunnel specifications, characteristics of the fire, and relation of smoke control and evacuation direction. So in this study, it is conducted that how the way of smoke control and the relation of smoke control and evacuation direction affect quantitative risk assessment with variables (the tunnel length (2, 3, 4, 5, 6 km) and the slope (5, 15, 25‰)). As the result, in a train fire at the double track tunnel (Area = $97m^2$), it is most efficient to evacuate to the opposite direction of smoke control regardless of the location of train in train fire. In addition, under the same condition, index risk in mechanical ventilation up to 1/10.