• Nuclear Engineering and Technology
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• v.46 no.1
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• pp.11-26
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• 2014

The analyses carried out within the Seismic Probabilistic Risk Assessments (SPRAs) of Nuclear Power Plants (NPPs) are affected by significant aleatory and epistemic uncertainties. These uncertainties have to be represented and quantified coherently with the data, information and knowledge available, to provide reasonable assurance that related decisions can be taken robustly and with confidence. The amount of data, information and knowledge available for seismic risk assessment is typically limited, so that the analysis must strongly rely on expert judgments. In this paper, a Dempster-Shafer Theory (DST) framework for handling uncertainties in NPP SPRAs is proposed and applied to an example case study. The main contributions of this paper are two: (i) applying the complete DST framework to SPRA models, showing how to build the Dempster-Shafer structures of the uncertainty parameters based on industry generic data, and (ii) embedding Bayesian updating based on plant specific data into the framework. The results of the application to a case study show that the approach is feasible and effective in (i) describing and jointly propagating aleatory and epistemic uncertainties in SPRA models and (ii) providing 'conservative' bounds on the safety quantities of interest (i.e. Core Damage Frequency, CDF) that reflect the (limited) state of knowledge of the experts about the system of interest.

• Journal of the Korea Society of Computer and Information
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• v.23 no.11
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• pp.75-84
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• 2018

Social engineering attack means to get information of Social engineering attack means to get information of opponent without technical attack or to induce opponent to provide information directly. In particular, social engineering does not approach opponents through technical attacks, so it is difficult to prevent all attacks with high-tech security equipment. Each company plans employee education and social training as a countermeasure to prevent social engineering. However, it is difficult for a security officer to obtain a practical education(training) effect, and it is also difficult to measure it visually. Therefore, to measure the social engineering threat, we use the results of social engineering training result to calculate the risk by system asset and propose a attack graph based probability. The security officer uses the results of social engineering training to analyze the security threats by asset and suggests a framework for quick security response. Through the framework presented in this paper, we measure the qualitative social engineering threats, collect system asset information, and calculate the asset risk to generate probability based attack graphs. As a result, the security officer can graphically monitor the degree of vulnerability of the asset's authority system, asset information and preferences along with social engineering training results. It aims to make it practical for companies to utilize as a key indicator for establishing a systematic security strategy in the enterprise.

• Earthquakes and Structures
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• v.16 no.6
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• pp.705-714
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• 2019

Seismic assessment of underground structures is one of the challenging problems in engineering design. This is because there are usually many sources of uncertainties in rocks and probable earthquake characteristics. Therefore, for decreasing of the uncertainties, seismic response of underground structures should be evaluated by sufficient number of earthquake records which is scarcely possible in common seismic assessment of underground structures. In the present study, a practical risk-based approach was performed for seismic risk assessment of an unsupported tunnel. For this purpose, Incremental Dynamic Analysis (IDA) was used to evaluate the seismic response of a tunnel in south-west railway of Iran and different analyses were conducted using 15 real records of earthquakes which were chosen from the PEER ground motion database. All of the selected records were scaled to different intensity levels (PGA=0.1-1.7 g) and applied to the numerical models. Based on the numerical modeling results, seismic fragility curves of the tunnel under study were derived from the IDA curves. In the next, seismic risk curve of the tunnel were determined by convolving the hazard and fragility curves. On the basis of the tunnel fragility curves, an earthquake with PGA equal to 0.35 g may lead to severe damage or collapse of the tunnel with only 3% probability and the probability of moderate damage to the tunnel is 12%.

• Journal of the Korea Safety Management & Science
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• v.24 no.4
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• pp.61-70
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• 2022

In spite of lab safety act for over 10 years, over 100 safety accidents in the laboratory have been constantly occurring. The ideal safety management system is to prevent accidents by differential classifying and managing laboratory regulatory materials according to the risk level. In order to approach this system, in-depth interviews with safety managers were first conducted to identify the current status of safety management in domestic university laboratories. And then through comparative analysis of safety management systems in domestic and foreign laboratories, a new regulatory substance classification standard based on the analysis of the hazards and the classification of risk grades, and a safety management system are proposed. From this study, it will contribute to the creation of a safe laboratory environment by differential classification and management laboratory regulatory materials based on the risk level.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.9
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• pp.75-91
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• 2022

This study assesses the Internet banking adoption tendency by existing bank customers of Bangladesh. Currently, almost all the leading banks in the country have implemented Internet banking platforms. However, the active user count remains relatively low and there hasn't been any conclusive research on the drivers and inhibitors of Internet banking. This study evaluates the reasons and quantitatively establishes the factors leading to the adoption and usage continuance of internet banking by existing bank customers. Responses from 460 bank account holders were collected via online questionnaires using a purposive sampling approach, and a core conceptual framework based on Technology Acceptance Model (TAM) and Technology Readiness Index (TRI) was used. The study concluded that internet banking adoption is significantly impacted by the ease of use, customer service, and technology familiarity. Similarly, customer satisfaction is affected by the perceived value and the perceived risk. Through regression analysis, it was found that usage continuance is 89% explained by adoption and customer satisfaction. Multi-group moderation showed significant impact by groups divided based on usage frequency, income level, and age. Perceived risk weakened the impact of perceived value and technology familiarity on usage adoption. Additionally, perceived risk reduced the impact of consumer satisfaction and usage continuance.

• Asia-Pacific Journal of Business
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• v.13 no.4
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• pp.163-175
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• 2022

Purpose - This study introduces a methodology for finding the optimal tracking error of active stock funds. Tracking error is commonly used in risk budgeting techniques as a concept of cost for alpha creation. Design/methodology/approach - This study uses a post-optimal smart beta portfolio that maximizes alpha under the given tracking error constraint. Findings - As a result of the analysis, the smart beta strategy that maximized alpha under the constraint of 0.15% daily tracking error shows the highest IR. This means the maximum theoretically achievable efficiency. In this regard, a fixed-effect panel regression analysis is conducted to evaluate the active efficiency of domestic stock funds. In addition to control variables based on previous studies, the effect of tracking error on alpha is analyzed. The alpha used in this model is calculated using the smart beta portfolio according to the size of the constraint of the tracking error as a benchmark. Contrary to theoretical estimates, in Korea, the alpha performance is maximized under a daily tracking error of 0.1%. This indicates that the active efficiency of domestic equity funds is lower than the theoretical maximum. Research implications or Originality - Based on this study, it is expected that it can be used for active risk management of pension funds and performance evaluation of active strategies.

• Asia-Pacific Journal of Business
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• v.12 no.1
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• pp.135-149
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• 2021

Purpose - I analyzes risk-to-performance evaluated in the market using data from sale and lease back. Specifically, I analyze from the perspective of financial institutions that purchase sale and lease back based on the cases of investment by ship investment companies and acquisition of ships. Design/methodology/approach - I use 49 sale and lease back data from 2017 to 2019 for empirical analysis. Findings - The main results of this paper are as follows. First, after sale and lease back of domestic ships, the average amount of sales by the leased shipping company is 25.1 billion won, the average amount of investment by the purchased financial institution is 14.6 billion won (60%) and the average length of the ship is nine years. In ship finance, sale and lease back is deemed to be appropriately used as a means of restructuring for a large amount of money. Second, the main risk factor for sale and lease back of domestic ships is credit risk and can be measured in VaR in practice. As a result of the empirical analysis, the average credit risk burden ratio is 9%. As a major risk factor, low creditworthiness of restructuring companies is the key. Third, as a result of measuring the profitability of financial institutions that purchase sale and lease back of domestic ships at a net current price, it has an average value of 300 million won, but the deviation by case is very large. Fourth, the risk adjusted performance of sale and lease back of domestic ships is 0.54 on average compared to the total risk capital, and 0.52 compared to the stock-risk capital, and as with profitability earlier, the deviation of each case is very large and misaligned. In order to boost the sale and lease back market for large and long-term assets, in order to overcome low profitability as a prerequisite for future participation of commercial purchased financial institutions, it is expected that purchase decisions based on expectations versus risk will be necessary. Research implications or Originality - The results of this paper are expected to broaden the understanding of sale and lease back and foster the ability to assess long-term risk and performance. Based on this, it is believed that rapid restructuring of companies through sale and lease back of large amounts of long-term assets will greatly increase the utility of the domestic financial market.

• Journal of Distribution Science
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• v.14 no.6
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• pp.89-98
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• 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.

• Journal of Navigation and Port Research
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• v.41 no.3
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• pp.93-102
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• 2017

When VTSOs (Vessel Traffic Service Operator) determine the degree of collision risk for two vessels, they consider comprehensive information about each vessel's course, speed, DCPA, TCPA, and encountering situation. In this study, we proposed a utility function based on the risk attitudes of VTSOs toward the Risk Index (RI). The RI was calculated using the risk of encounter, the risk of approach, and the risk of time for two vessels in order to predict each ship's collision risk from the VTS viewpoint. We obtained each coefficient of the RI and the risk attitude through a survey of collision risks among VTSOs of Korea. In order to verify whether the proposed utility is reasonable, we validated by applying the degree of collision risk to some historical cases of accidents in Busan port along with the Ship of ES value($ES_S$) of ES(Environmental Stress) model.

• Journal of Technology Innovation
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• v.21 no.1
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• pp.165-198
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• 2013

The purpose of the study is to identify risk factors and analyze risk impacts to increase R&D outcome by taking into consideration the activities undertaken in each phase of New Product Development(NPD) process. The paper builds on survey research that has been developed new IT products within the past 5 years at SAMSUNG and LG subsidiaries in the Republic of Korea. This study identified risk factors in accordance with NPD process and evaluated the identified risk factors with survey questionnaires. To analyze the risk impacts were used to perform a logistic regression analysis based on R&D output. The impact of risk factors were higher for the low-output group. High-output group took a risk into consideration unique undertakings in project management and managed risk factors effectively in order to increase R&D output. Consequently, with the aim of improving output of R&D, a risk management is necessary to identify the risk factors for each phase of NPD and focus on managing risk factors with great effect.