• Title/Summary/Keyword: the risk model

Search Result 5,295, Processing Time 0.033 seconds

An Alternative Risk Assessment Model in EMS (환경경영시스템에서의 위험평가 모델)

  • 김종걸;김창수
    • Proceedings of the Safety Management and Science Conference
    • /
    • 2004.05a
    • /
    • pp.271-276
    • /
    • 2004
  • The risk assessment model is an important subsystem for effective establishment and operation of EMS (environment management system). In case of poor risk assessment long-term and large-scale failure expense might be brought. Managing policy, target and other indices based on risk assessment can guarantee successful EMS. In this paper, we aim at comparative analysis of various risk methods and propose an alternative risk assessment model for EMS.

  • PDF

A TBM tunnel collapse risk prediction model based on AHP and normal cloud model

  • Wang, Peng;Xue, Yiguo;Su, Maoxin;Qiu, Daohong;Li, Guangkun
    • Geomechanics and Engineering
    • /
    • v.30 no.5
    • /
    • pp.413-422
    • /
    • 2022
  • TBM is widely used in the construction of various underground projects in the current world, and has the unique advantages that cannot be compared with traditional excavation methods. However, due to the high cost of TBM, the damage is even greater when geological disasters such as collapse occur during excavation. At present, there is still a shortage of research on various types of risk prediction of TBM tunnel, and accurate and reliable risk prediction model is an important theoretical basis for timely risk avoidance during construction. In this paper, a prediction model is proposed to evaluate the risk level of tunnel collapse by establishing a reasonable risk index system, using analytic hierarchy process to determine the index weight, and using the normal cloud model theory. At the same time, the traditional analytic hierarchy process is improved and optimized to ensure the objectivity of the weight values of the indicators in the prediction process, and the qualitative indicators are quantified so that they can directly participate in the process of risk prediction calculation. Through the practical engineering application, the feasibility and accuracy of the method are verified, and further optimization can be analyzed and discussed.

Risk Assessments for Ports and Waterways

  • Jeong, Duke H.;Harrald, John R.
    • Proceedings of KOSOMES biannual meeting
    • /
    • 1999.03a
    • /
    • pp.43-51
    • /
    • 1999
  • The objective of this research is to ensure that the ports and waterways management system can establish and maintain a reasonable level of safety level during high density passenger operations. The research model was developed included computer based model that could be used that can be used to measure and monitor risk and evolved overtime. The research methodology provides model for assessing relative risk and evaluating risk reduction measures. The risk analysis based on expert judgement was refined overtime. They provide a basis for risk reduction and risk management policies and strategies. The evaluation and validation of risk model and development of data, methods, tools required to measure, monitor and evaluate ports and waterway risk was implemented.

  • PDF

Risk Monitor Development for On-Line Maintenance (가동중 정비를 위한 Risk Monitor 개발)

  • 김길유;한상훈;김태운
    • Journal of the Korean Society of Safety
    • /
    • v.12 no.4
    • /
    • pp.21-26
    • /
    • 1997
  • Korea Atomic Energy Research Institute (KAERI) developed a risk monitor called Risk Monster which supports for plant operators and maintenance schedulers to monitor plant risk and to avoid high peak risk by rearranging maintenance work schedule. Risk Monster can update the plant risk continuously according to the change of system/component configuration since Risk Monster reevaluates the plant risk based on the Probabilistic Safety Assessment (PSA) results. A brief description of Risk Monster is provided. The PSA model of UCN 3, 4 nuclear power plant was converted by KAERI to Risk Monster model. Using this Risk Monster model, a feasibility study of the on-line maintenance of an Essential Service Water (ESW) pump was performed. On-line maintenance of one ESW pump has been shown to be acceptably safe, and has economic benefits. In addition, it is not a violation of technical specification to continue plant operation with an out-of-service ESW pump.

  • PDF

Development of the Risk Assessment Model for Train Collision and Derailment (열차 충돌/탈선사고 위험도 평가모델 개발)

  • Choi, Don-Bum;Wang, Jong-Bae;Kwak, Sang-Log;Park, Chan-Woo;Kim, Min-Su
    • Proceedings of the KSR Conference
    • /
    • 2008.06a
    • /
    • pp.1518-1523
    • /
    • 2008
  • Train collision and derailment are types of accident with low probability of occurrence, but they could lead to disastrous consequences including loss of lives and properties. The development of the risk assessment model has been called upon to predict and assess the risk for a long time. Nevertheless, the risk assessment model is recently introduced to the railway system in Korea. The classification of the hazardous events and causes is the commencement of the risk assessment model. In previous researches related to the classification, the hazardous events and causes were classified by centering the results. That classification was simple, but might not show the root cause of the hazardous events. This study has classified the train collision and derailment based on the relevant hazardous event including faults of the train related the accidents, and investigates the causes related to the hazardous events. For the risk assessment model, FTA (fault tree analysis) and ETA (event tree analysis) methods are introduced to assess the risk.

  • PDF

Systematic Risk Analysis on Bitcoin Using GARCH Model (GARCH 모형을 활용한 비트코인에 대한 체계적 위험분석)

  • Lee, Jung Mann
    • Journal of Information Technology Applications and Management
    • /
    • v.25 no.4
    • /
    • pp.157-169
    • /
    • 2018
  • The purpose of this study was to examine the volatility of bitcoin, diagnose if bitcoin are a systematic risk asset, and evaluate their effectiveness by estimating market beta representing systematic risk using GARCH (Generalized Auto Regressive Conditional Heteroskedastieity) model. First, the empirical results showed that the market beta of Bitcoin using the OLS model was estimated at 0.7745. Second, using GARCH (1, 2) model, the market beta of Bitcoin was estimated to be significant, and the effects of ARCH and GARCH were found to be significant over time, resulting in conditional volatility. Third, the estimated market beta of the GARCH (1, 2), AR (1)-GARCH (1), and MA (1)-GARCH (1, 2) models were also less than 1 at 0.8819, 0.8835, and 0.8775 respectively, showing that there is no systematic risk. Finally, in terms of efficiency, GARCH model was more efficient because the standard error of a market beta was less than that of the OLS model. Among the GARCH models, the MA (1)-GARCH (1, 2) model considering non-simultaneous transactions was estimated to be the most appropriate model.

Developing a Product Risk Assessment Model for Korea Using Injury Data (위해정보를 활용한 한국형 제품 위험성 평가 모델 개발에 관한 연구)

  • Bae, Jinhan;Song, HaeGeun;Park, Young T.
    • Journal of Korean Society for Quality Management
    • /
    • v.41 no.4
    • /
    • pp.623-635
    • /
    • 2013
  • Purpose: The recent major recalls of hazardous products caused consumer product safety acts to be strengthen worldwide. Although the recall system of hazardous products in Korea has been operating based on Framework Act on Product Safety since 2011, the evaluation of product risk has been relied on not the results of objective incident data but the results of illegal product investigations. The purpose of this paper is to propose a product risk assessment model for Korea using injury data. Methods: The authors derived Korea's risk assessment method by analysing the advantages and disadvantages of the most widely used models in advanced countries such as EU's RAPEX RAG and Janpan's R-MAP. In this study, the level of relative frequency and severity of injury are determined based on the objective incident data and the length of hospitalization respectively. In addition, the injury data occurred during 2011 is applied to the proposed risk assessment model for case study. Results: The data analysed in this paper can be classified as high risk, medium risk, low risk, acceptable risk, and safe products through the matrix f rom the combination of the relative frequency and the severity derived. Conclusion: The proposed risk assessment model in this study has advantage obtaining reliable objective results because it uses actual injury data and redeems the drawbacks of the existing models used in advanced countries. Furthermore, because the proposed model shows the high risk products among many, it is expected to be useful especially for customs whose main job is inspecting the imported goods and the government when selecting the target product groups for safety investigation.

Applications of SMCRE Model on Social Amplification of MERS Risk Information and its Implications (메르스 위험정보유통의 사회적 확산에 관한 SMCRE 모형의 적용과 함의)

  • Choi, Choong-Ik;Bae, Suk-Kyeong;Kim, Chul-Min
    • Journal of Distribution Science
    • /
    • v.14 no.6
    • /
    • pp.89-98
    • /
    • 2016
  • Purpose - This article tackles risk communication issues and aims to address the characteristics of MERS risk information distribution in South Korea, and secondly to examine the communicative behavior of the public health authority in terms of the quality of communication strategies. Thirdly, the study attempts to figure out the risk communication to cope with MERS through the applications of SMCRE model in chronological order. We employ the social amplification of risk framework for analyzing the emergent public response as one of the main approaches. Research Design, Data and Methodology - The main framework of this study is theoretically based on the social amplification of risk, which describes signals about risk transmitted and processed by individuals and social groups. The model also reflects the interactions between social groups and institutes about disaster-related risk issues, which are potential amplifiers or attenuators of communication signals. S-M-C-R-E Model is methodologically employed to examine the social amplification for MERS risk information in each period, which we defined operationally. The proposed methodology allows the assessment of effectiveness and ineffectiveness on risk communication to be conceptualized as a countermeasure against disasters. The paper focuses on exploring how social risk amplification can be applied and organized in each stage. Results - The SMCRE model describes the exchange of risk information and is also applied to all forms of communication between stakeholders including public health authority, local government and media. Each factor of risk communication includes source, message, channel, receiver and effect. The results support that the effective risk communication involves not only the improved reliability of public health authority as a key factor of risk communication, but also a close cooperation and good collaboration with local governments. It does not seem to be possible that the government-initiated risk communication based on controllability and management cope effectively with infectious disease in early stage. The results of this study imply that the shared risks between local, regional and national authorities can enhance risk communication system. Conclusions - The study supports that the disparities in how disaster-related risk information is interpreted and coded, have made effective risk communication and public sense-making impeded. Our findings support a more communicative discussion about the role of risk information sharing between governments for the improvement of emergency management and underline the importance of social elements in the risk communication, such as relationship and trust building. Findings suggest that trust building between stakeholders could be added to help explain the processes of social amplification and attenuation of risk. It would be recommended that the continuous risk communication with all the involved stakeholders will be able to help national health promotion policy to be improved regarding emergency management. Furthermore, risk communication has to be a scientific approach for the communication pertaining to potentially sensitive or controversial situations with public concerns and low public trust.

The Relationship between Default Risk and Asset Pricing: Empirical Evidence from Pakistan

  • KHAN, Usama Ehsan;IQBAL, Javed
    • The Journal of Asian Finance, Economics and Business
    • /
    • v.8 no.3
    • /
    • pp.717-729
    • /
    • 2021
  • This paper examines the efficacy of the default risk factor in an emerging market context using the Fama-French five-factor model. Our aim is to test whether the Fama-French five-factor model augmented with a default risk factor improves the predictability of returns of portfolios sorted on the firm's characteristics as well as on industry. The default risk factor is constructed by estimating the probability of default using a hybrid version of dynamic panel probit and artificial neural network (ANN) to proxy default risk. This study also provides evidence on the temporal stability of risk premiums obtained using the Fama-MacBeth approach. Using a sample of 3,806 firm-year observations on non-financial listed companies of Pakistan over 2006-2015 we found that the augmented model performed better when tested across size-investment-default sorted portfolios. The investment factor contains some default-related information, but default risk is independently priced and bears a significantly positive risk premium. The risk premiums are also found temporally stable over the full sample and more recent sample period 2010-2015 as evidence by the Fama-MacBeth regressions. The finding suggests that the default risk factor is not a useless factor and due to mispricing, default risk anomaly prevails in the Pakistani equity market.

A Study on Cost Risk Estimation applying Joint Cost-Schedule Probability Distribution Model (비용과 일정의 결합확률 분포를 적용한 위험비용추정에 관한 연구)

  • Kim, Dong-Kyu;Kang, Sung-Jin;Han, Gyu-Sik
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.14 no.5
    • /
    • pp.850-858
    • /
    • 2011
  • The risk analysis plays an important role in weapon system acquisition project due to uncertainties in the acquisition process. But in domestic, studies on risk analysis are insufficient and risk cost is not included in acquisition budget in policy. Therefore, in this study, we suggest a method that measures risk or success probability of project using the stochastic model. In particular, in order to calculate the success probability, we apply the joint probability distribution model of cost and schedule that are critical factors influencing the project risk. And also we verify the applicability of this model in Korean defence industry environment through case studies.