• Title, Summary, Keyword: risk index

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A method to evaluate the risk-based robustness index in blast-influenced structures

  • Abdollahzadeh, Gholamreza;Faghihmaleki, Hadi
    • Earthquakes and Structures
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    • v.12 no.1
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    • pp.47-54
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    • 2017
  • Introduction of robustness index in the structure is done in three ways: deterministic robustness index, probabilistic robustness index, and risk-based robustness index. In past decades, there have been numerous researches to evaluate robustness index in both deterministic and probabilistic ways. In this research, by using a risk analysis, a risk-based robustness index has been defined for the structure. By creating scenarios in accordance with uncertainty parameters of critical and unexpected gas blast accident, a new method has been suggested for evaluating risk-based robustness index. Finally, a numerical example for the evaluation of risk-based robustness index of a four-storey reinforced concrete moment frame, designed and built based on Eurocode 8 code, has been presented with results showing a lower risk of robustness.

A Noise-Reduced Risk Aversion Index

  • Park, Beum-Jo;Cho, Hong Chong
    • Journal of Information Technology Applications and Management
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    • v.25 no.1
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    • pp.67-85
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    • 2018
  • We propose a noise reduced risk aversion index for measuring risk aversion through a laboratory experiment to overcome disadvantages of the multiple pricing list format developed by Holt and Laury (2002). We use randomized multiple list choices with coarser classification and reward weighting, supplement the rank of risk aversion with extra individual characteristics of risk attitude, and construct an index of risk aversion by standardizing the risk aversion ranking with quantile normalization. Our method reduces multiple switching problems that noisy decision makers mistakenly commit in experimental approaches, so that it is free of the framing effect which severely occurred in the HL. Furthermore, the index doesn't utilize any specific utility function or probability weighting, which allows researcher to hold the independence axiom. Since our noise reduced index of risk aversion has many good traits, it is widely used and applied to reveal fundamental characteristics of risk-related behaviors in economics and finance regardless of experimental environment.

DEVELOPMENT OF ROBUST LATERAL COLLISION RISK ASSESSMENT METHOD (측후방 충돌 안전 시스템을 위한 횡방향 충돌 위험 평가 지수 개발)

  • Kim, Kyuwon;Kim, Beomjun;Kim, Dongwook;Yi, Kyongsu
    • Journal of Auto-vehicle Safety Association
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    • v.5 no.1
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    • pp.44-49
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    • 2013
  • This paper presents a lateral collision risk index between an ego vehicle and a rear-side vehicle. The lateral collision risk is designed to represent a lateral collision risk and provide the appropriate threshold value of activation of the lateral collision management system such as the Blind Spot Detection(BSD). The lateral collision risk index is designed using the Time to Line Crossing(TLC) and the longitudinal collision index at the predicted TLC. TLC and the longitudinal collision index are calculated with the signals from the exterior sensor such as the radar equipped on the rear-side of a vehicle and a vision sensor which detects the distance and time to the lane departure. For the robust situation assessment, the perception of driving environment determining whether the road is straighten or curved should be determined. The relative motion estimation method has been proposed with the road information via the integrated estimator using the environment sensors and vehicle sensor. A lateral collision risk index was composed with the estimated relative motion considering the relative yaw angle. The performance of the proposed lateral collision risk index is investigated via computer simulations conducted using the vehicle dynamics software CARSIM and Matlab/Simulink.

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Predicting the Potential Habitat and Risk Assessment of Amaranthus patulus using MaxEnt (Maxent를 활용한 가는털비름(Amaranthus patulus)의 잠재서식지 예측 및 위험도 평가)

  • Lee, Yong Ho;Na, Chea Sun;Hong, Sun Hea;Sohn, Soo In;Kim, Chang Suk;Lee, In Yong;Oh, Young Ju
    • Korean Journal of Environmental Biology
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    • v.36 no.4
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    • pp.672-679
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    • 2018
  • This study was conducted to predict the potential distribution and risk of invasive alien plant, Amaranthus patulus, in an agricultural area of South Korea. We collected 254 presence localities of A. patulus using field survey and literature search and stimulated the potential distribution area of A. patulus using maximum entropy modeling (MaxEnt) with six climatic variables. Two different kinds of agricultural risk index, raster risk index and regional risk index, were estimated. The 'raster risk index' was calculated by multiplying the potential distribution by the field area in $1{\times}1km$ and 'regional risk index' was calculated by multiplying the potential distribution by field area proportion in the total field of South Korea. The predicted potential distribution of A. patulus was almost matched with actual presence data. The annual mean temperature had the highest contribution for distribution modeling of A. patulus. Area under curve (AUC) value of the model was 0.711. The highest regions were Gwangju for potential distribution, Jeju for 'raster risk index' and Gyeongbuk for 'regional risk index'. This different ranks among the index showed the importance about the development of various risk index for evaluating invasive plant risk.

A Determining Contingency Ranking Using the Weather Effects of the Power System (날씨효과를 고려한 전력계통의 상정사고 순위 결정)

  • 김경영;이승혁;김진오;김태균;전동훈;차승태
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.53 no.9
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    • pp.487-493
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    • 2004
  • The electric power industry throughout the world is undergoing considerable changes from the vertically integrated utility structure to the deregulated market. However, the deregulated electricity market is operated with respect to theory of economical efficiency, and therefore, the system operator requires data with fast contingency ranking for security of the bulk power system. This paper compares the weather dependant probabilistic risk index(PRI) with the system performance index for power flow in the IEEE-RTS. The system performance index for power flow presents the power system stability. This paper presents fast calculation method for determining contingency ranking using the weather dependant probabilistic risk index(PRI). The probabilistic risk index can be classified into the case of normal and adverse weather. This paper proposes calculation method using the probabilistic risk index in determining contingency ranking required for security under the deregulated electricity market.

Proposing a Method for Robustness Index Evaluation of the Structures Based on the Risk Analysis of Main Shock and Aftershock

  • Abdollahzadeh, Gholamreza;Faghihmaleki, Hadi
    • International journal of steel structures
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    • v.18 no.5
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    • pp.1710-1722
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    • 2018
  • Investigating remained damages from terrible earthquakes, it could be concluded that some events including explosion because of defect and failure in the building mechanical facilities or caused by gas leak, firing, aftershocks, etc., which are occurred during or a few time after the earthquake, will increase the effects of damages. In this paper, by introducing a complete risk analysis which included direct and indirect risks for earthquake (the main shock) and aftershock, the corresponding robustness index was created that called as "robustness index sequential critical events risk-based". One of the main properties of the intended robustness index is using progressive collapse percentage in its evaluation. Then, in a numerical example for a 4-storey moment resisting steel frame structure, a method is presented for obtaining all effective parameters in robustness index evaluation based on the intended risk and at last its results were reported.

A Study on the Risk Index Model of Work Type in Architectural Construction Work (건축공사 공종별 위험지수 산정모델에 관한 연구)

  • Chang, Seong-Rok;Go, Seong-Seok;Lee, Jong-Bin
    • Journal of the Korean Society of Safety
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    • v.22 no.6
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    • pp.63-68
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    • 2007
  • The purpose of this study is to verify the relation between the risk index using AHP(Analytic Hierarchy Process) and the risk index using Computing Model. For doing the objective, this research classified 22 work types in architectural construction work from the analysis Korean architectural standard specification and Korea occupational safety & health agency code. Based on the classified 22 work types in architectural construction work, the risk index of each work type was calculated by AHP and Computing Model. For verifying the correlation of risk index between AHP and Computing Model methods, SAS version 8.0 System, which is one of the statistics programs, was used.

Development and Application of Risk Recovery Index using Machine Learning Algorithms (기계학습알고리즘을 이용한 위험회복지수의 개발과 활용)

  • Kim, Sun Woong
    • Journal of Information Technology Applications and Management
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    • v.23 no.4
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    • pp.25-39
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    • 2016
  • Asset prices decline sharply and stock markets collapse when financial crisis happens. Recently we have encountered more frequent financial crises than ever. 1998 currency crisis and 2008 global financial crisis triggered academic researches on early warning systems that aim to detect the symptom of financial crisis in advance. This study proposes a risk recovery index for detection of good opportunities from financial market instability. We use SVM classifier algorithms to separate recovery period from unstable financial market data. Input variables are KOSPI index and V-KOSPI200 index. Our SVM algorithms show highly accurate forecasting results on testing data as well as training data. Risk recovery index is derived from our SVM-trained outputs. We develop a trading system that utilizes the suggested risk recovery index. The trading result records very high profit, that is, its annual return runs to 121%.

Development of Risk Rating and Index for Coastal Activity Locations

  • Lee, Young-Jai;Jung, Cho-Young;Gu, Ja-Yeong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.26 no.3
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    • pp.227-232
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    • 2020
  • This paper develops a risk index based on an indicator of risk assessment in terms of coastal activity location and accident type. The risk index is derived from a formula which adds the consequence of failure to a vulnerability value, then subtracts the mitigation value. Specifically, the consequence of failure is the number of casualties in coastal activity locations. An indicator of vulnerability refers to coastal environment elements and social elements. A pointer of mitigation includes managerial and organizational elements that indicate the capabilities of coastal activities. A risk rating of coastal activity location is found from a risk matrix consisting of the accident location and type. The purpose of this study is to prevent accidents at coastal activity locations by allowing the Coastal police guard to monitor effectively and inform visitors of potential risks.

Optimal Asset Allocation with Minimum Performance and Inflation Risk (최소 자산제약 및 인플레이션을 고려한 자산 할당에 관한 연구)

  • Lim, Byung Hwa
    • Korean Management Science Review
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    • v.30 no.1
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    • pp.167-181
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    • 2013
  • We investigate the dynamic asset allocation problem under inflation risk when the wealth of an investor is constrained with minimum requirements. To capture the investor's risk preference, the CRRA utility function is considered and he maximizes his expected utility at predetermined date of the refund by participation in the financial market. The financial market is supposed to consist of three kinds of financial instruments which are a risk free asset, a risky asset, and an index bond. The role of an index bond is managing inflation risk represented by price process. The optimal wealth and the optimal asset allocation are derived explicitly by using the method to get the European call option pricing formula. From the numerical results, it is confirmed that the investments on index bond is high when the investor's wealth level is low. However, as his wealth increases, the investments on index bond decreases and he invests on risky asset more. Furthermore, the minimum wealth constraint induces lower investment on risky asset but the effect of the constraints is reduced as the wealth level increases.