• Title/Summary/Keyword: hazard assessment

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Causal Factors of Hazardous Event for People Struck Considering Environment Properties (환경특성을 고려한 열차충격 위험사건의 원인 인자 분석)

  • Kim, Min-Su;Wang, Jong-Bae;Park, Chan-Woo;Choi, Don-Bum
    • Proceedings of the KSR Conference
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    • 2008.11b
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    • pp.2116-2120
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    • 2008
  • Recently, in the national railway industry there has been interested in the methodology of hazard analysis and risk assessment. The need of safety management system based on the technology of hazard analysis and risk assessment is being extended to identify in advance the weakness and threat factors causing the accident and cope with the accident actively. It is important to manage the risk of railway casualty accidents having a majority of railway accident. Especially, a hazard event of people struck takes the highest proportion of the railway casualty accidents. This paper describes the result of analysis for environment properties such as an age of casualty, time happened, day, month and weather conditions being concerned in the hazard event of people struck.

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Seismic hazard assessment for two cities in Eastern Iran

  • Farzampour, Alireza;Kamali-Asl, Arash
    • Earthquakes and Structures
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    • v.8 no.3
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    • pp.681-697
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    • 2015
  • Iran as one of the countries located on the Alpine-Himalayan seismic belt has recently experienced a few number of catastrophic earthquakes. A well-known index of how buildings are affected by earthquakes is through assessment of probable Peak Ground Acceleration (PGA) and structures' response spectra. In this research, active faults around Kerman and Birjand, two major cities in eastern parts of Iran, have been considered. Seismic catalogues are gathered to categorize effects of surrounding faults on seismicity of the region. These catalogues were further refined with respect to time and space based on Knopoff-Gardner algorithm in order to increase statistical independency of events. Probabilistic Seismic Hazard Analysis (PSHA) has been estimated for each of cities regarding 50, 100, 200 and 500 years of structures' effective life-span. These results subsequently have been compared with Deterministic Seismic Hazard Analysis (DSHA). It has been observed that DSHA not necessarily suggests upper bound of PSHA results. Furthermore, based on spectral Ground Motion Prediction Equations (GMPEs), Uniform Hazard Spectra (UHS) and spectral acceleration were provided for 2% and 10% levels of probability of exceedance. The results show that increasing source-to-site distance leads to spectral acceleration reduction regarding each fault. In addition, the spectral acceleration rate of variation would increase if the source-to-site distance decreases.

Suggestion on Seismic Hazard Assessment of Nuclear Power Plant Sites in Korea (국내 원전부지 지진재해도 평가를 위한 제언)

  • Kang, Tae-Seob;Yoo, Hyun Jae
    • Economic and Environmental Geology
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    • v.51 no.2
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    • pp.203-211
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    • 2018
  • Issues with past practice in seismic hazard analysis of nuclear power plant sites in Korea are addressed. Brief review on both deterministic and probabilistic methods in seismic hazard analysis is given, and most of the continuing discussion is focussed on the probabilistic seismic hazard analysis. Causes of uncertainty are traced on the basis of the cases that the assessment methodology was applied to the nuclear power plant sites. Considerations on the assessment include the role of experts, a representative seismic catalog, seismic source zonation, earthquake ground-motion relationship, and evaluation process. Factors increasing uncertainty in each item are analyzed and some feasible solutions are discussed.

Estimation of Wave Parameters for Probabilistic Tsunami Hazard Analysis Considering the Fault Sources in the Western Part of Japan (일본 서부 단층 지진원을 고려한 확률론적 지진해일 재해도 분석의 파고 변수 도출)

  • Rhee, Hyun-Me;Kim, Min Kyu;Sheen, Dong-Hoon;Choi, In-Kil
    • Journal of the Earthquake Engineering Society of Korea
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    • v.18 no.3
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    • pp.151-160
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    • 2014
  • Probabilistic tsunami hazard analysis (PTHA) is based on the approach of probabilistic seismic hazard analysis (PSHA) which is performed using various seismotectonic models and ground-motion prediction equations. The major difference between PTHA and PSHA is that PTHA requires the wave parameters of tsunami. The wave parameters can be estimated from tsunami propagation analysis. Therefore, a tsunami simulation analysis was conducted for the purpose of evaluating the wave parameters required for the PTHA of Uljin nuclear power plant (NPP) site. The tsunamigenic fault sources in the western part of Japan were chosen for the analysis. The wave heights for 80 rupture scenarios were numerically simulated. The synthetic tsunami waveforms were obtained around the Uljin NPP site. The results show that the wave heights are closely related with the location of the fault sources and the associated potential earthquake magnitudes. These wave parameters can be used as input data for the future PTHA study of the Uljin NPP site.

Categorizing Safety Management Elements for Fire Preparation and Assessemnt of Fire Hazard (화재에 대비한 지하공간의 안전관리 요소분류 및 화재위험성 평가방안)

  • Bae, Yoonshin;Park, Jihye
    • Journal of the Society of Disaster Information
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    • v.7 no.2
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    • pp.96-109
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    • 2011
  • In this study, risk categorized five safety management elements(equipment and structure, evacuation, lifesaving and fire extinguishing, performance based fire safety plan, operations management) were classified in order to establish safety system of underground space. Using classified safety management elements, assessment of fire hazard was performed. After calculating the grade of evaluation categories, assessment of fire hazard was suggested. The three grades of evaluation categories are classified as to importance and four criteria of evaluation are classified as to check result based on subdivisions.

Assessement of Rockfall Hazard in the Northeast Region of Ulleung-Do (울릉도 북동부 지역의 낙석재해 위험도 평가)

  • Seo, Yong-Seok;Jang, Hyung-Su;Kim, Kwang-Yeom
    • The Journal of Engineering Geology
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    • v.22 no.3
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    • pp.353-363
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    • 2012
  • The geology of Ulleung-Do is dominated by volcanic rocks with low strength and trachytic rocks with high strength but containing vertical joints that yield easily. Consequently, rockfalls along roadcuts are a major geological hazard, with the potential to affect the ring road of Ulleung-Do. In this study, we performed three types of rockfall hazard-risk assessment on the 3-km-long section of the ring road expected to have the highest possibility of rockfall. We used a rockfall ranking sheet in a roadside landslide hazard map, the Slope Stability Inspection Manual for National Highways (Japan), and a rockfall hazard rating system for inspection from the Japan Highway Public Corporation. We also employed the evaluation criteria of 'RHRS' developed by the Federal Highway Administration (FHA). An analysis of roadcuts at 27 sites with regard to geographic and geological conditions resulted in the identification of three classes of rockfall hazard (high, medium, and low). Of note, over 74% of slopes were assessed as high- and medium-class. Finally, a rockfall hazard map of the northeast region of Ulleung-Do was produced based on the evaluation results.

Quantitative Microbial Risk Assessment for Clostridium perfringens in Natural and Processed Cheeses

  • Lee, Heeyoung;Lee, Soomin;Kim, Sejeong;Lee, Jeeyeon;Ha, Jimyeong;Yoon, Yohan
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.8
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    • pp.1188-1196
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    • 2016
  • This study evaluated the risk of Clostridium perfringens (C. perfringens) foodborne illness from natural and processed cheeses. Microbial risk assessment in this study was conducted according to four steps: hazard identification, hazard characterization, exposure assessment, and risk characterization. The hazard identification of C. perfringens on cheese was identified through literature, and dose response models were utilized for hazard characterization of the pathogen. For exposure assessment, the prevalence of C. perfringens, storage temperatures, storage time, and annual amounts of cheese consumption were surveyed. Eventually, a simulation model was developed using the collected data and the simulation result was used to estimate the probability of C. perfringens foodborne illness by cheese consumption with @RISK. C. perfringens was determined to be low risk on cheese based on hazard identification, and the exponential model ($r=1.82{\times}10^{-11}$) was deemed appropriate for hazard characterization. Annual amounts of natural and processed cheese consumption were $12.40{\pm}19.43g$ and $19.46{\pm}14.39g$, respectively. Since the contamination levels of C. perfringens on natural (0.30 Log CFU/g) and processed cheeses (0.45 Log CFU/g) were below the detection limit, the initial contamination levels of natural and processed cheeses were estimated by beta distribution (${\alpha}1=1$, ${\alpha}2=91$; ${\alpha}1=1$, ${\alpha}2=309$)${\times}$uniform distribution (a = 0, b = 2; a = 0, b = 2.8) to be -2.35 and -2.73 Log CFU/g, respectively. Moreover, no growth of C. perfringens was observed for exposure assessment to simulated conditions of distribution and storage. These data were used for risk characterization by a simulation model, and the mean values of the probability of C. perfringens foodborne illness by cheese consumption per person per day for natural and processed cheeses were $9.57{\times}10^{-14}$ and $3.58{\times}10^{-14}$, respectively. These results indicate that probability of C. perfringens foodborne illness by consumption cheese is low, and it can be used to establish microbial criteria for C. perfringens on natural and processed cheeses.