• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.2
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• pp.9-17
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• 2019

In order to deal with high uncertainty and variability in emergency medical centers, many researchers have developed various models for their operational planning and scheduling. However, most of the models just provide static plans without any risk measures as their results, and thus the users often lose the opportunity to analyze how much risk the patients have, whether the plan is still implementable or how the plan should be changed when an unexpected event happens. In this study, we construct a simulation model combined with a risk-based planning and scheduling module designed by Simio LLC. In addition to static schedules, it provides possibility of treatment delay for each patient as a risk measure, and updates the schedule to avoid the risk when it is needed. By using the simulation model, the users can experiment various scenarios in operations quickly, and also can make a decision not based on their past experience or intuition but based on scientific estimation of risks even in urgent situations. An example of such an operational decision making process is demonstrated for a real mid-size emergency medical center located in Seoul, Republic of Korea. The model is designed for temporal short-term planning especially, but it can be expanded for long-term planning also with some appropriate adjustments.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1990.04a
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• pp.272-288
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• 1990

The uncertainty quantification process in probabilistic Risk Assessment usually involves a specification of the uncertainty in the input data and the propagation of this uncertainty to the final risk results. The distributional sensitivity analysis is to study the impact of the various assumptions made during the quantification of input parameter uncertainties on the final output uncertainty. The uncertainty importance of input parameters, in this case, should reflect the degree of changes in the whole output distribution and not just in a point estimate value. A measure of the uncertainty importance is proposed in the present paper. The measure is called the distributional sensitivity measure(DSM) and explicitly derived from the definition of the Kullback's discrimination information. The DSM is applied to three typical discrimination information. The DSM is applied to three typical cases of input distributional changes: 1) Uncertainty is completely eliminated, 2) Uncertainty range is increased by a factor of 10, and 3) Type of distribution is changed. For all three cases of application, the DSM-based importance ranking agrees very well with the observed changes of output distribution while other statistical parameters are shown to be insensitive.

• Journal of the Korean Society of Food Culture
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• v.23 no.4
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• pp.421-426
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• 2008

The purpose of this study was to measure the effects of trust, knowledge, optimism, risk and benefits on consumer attitudes toward genetically modified foods. A total of 326 questionnaires were completed. Moderated regression analysis was used to measure the relationships among the variables. The analysis results for the data indicated a good model fit in Model 2 rather than Model 1, in which the direct effects of trust, optimism and benefits had statistically significant direct effects on the respondents' attitudes toward genetically modified foods, while the direct effects of knowledge and risk were not statistically significant. As expected, the interaction term of risk and benefit had a significant effect on consumer attitude. Moreover, the effect of risk on consumer's attitude toward genetically modified foods was statistically significant at all levels of benefit, except at the lower benefit level. Finally, the results of this study indicated that genetically modified food developers and marketers should attach importance to the interaction effect of benefits to understand the elements of market demand and customer loyalty.

• East Asian mathematical journal
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• v.36 no.1
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• pp.55-60
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• 2020

We study a probabilistic approach for valuing an exchange option with default risk. The structural model of Klein [6] is used for modeling default risk. Under the structural model, we derive the closed-form pricing formula of the exchange option with default risk. Specifically, we provide the pricing formula of the option with the bivariate normal cumulative function via a change of measure technique and a multidimensional Girsanov's theorem.

• Proceedings of the Korea Database Society Conference
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• 2010.06a
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• pp.203-212
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• 2010

The mam purpose of this study is to find out how perceived risk elements influence to customers' perceived value and repurchase intention in the electronic commerce environment. To achieve the goal, we set 6 sub-dimensions - privacy risk, social risk, time loss risk, economic risk, psychological risk, and performance risk - based on comprehensive consideration of related studies, and established a research model included 2 factors such as perceived value and repurchase intention to measure performance in internet shopping malls. From 174 customers of the electronic commerce shopping malls survey data have been collected and analyzed based on the covariance structural model method. The results of this study are summarized as follows. Firstly, five perceived risk characteristics of privacy risk, time loss risk, economic risk, psychological risk, and performance risk are significantly positive effect on perceived value. Secondly, perceived value IS very significantly related to repurchase intention in electronic commerce shopping malls. Consequently, we discussed the strategies to create perceived value and repurchase intention in electronic commerce environment. Also we suggested the implications and further research directions.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.37
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• pp.187-216
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• 2008

Risk regarding the possibility of loss can be especially problematic. If a loss is certain to occur, it may be planned for in advance and treated as a definite, known expense. It is when there is uncertainty about the occurrence of a loss that risk becomes an important problem. The word risk is often used in connection with insurance. No one generally accepted definition of risk exists, however. Of the many definitions, two distinctive ones are commonly used. One defines risk as the variation in possible outcomes of an event based on chance. That is, the greater the number of different outcomes that may occur, the greater the risk. Another way of expressing this concept is to state: The greater the variation around an average expected loss, the greater the risk. The second definition of risk is the uncertainty concerning a possible loss. The definition of risk as a useful one because it focuses attention on the degree of risk in given situations. The degree of risk is a measure of the accuracy with which the outcome of an event based on chance can be predicted. For now, it will serve our purpose to note the more accurate the prediction of the outcome of an event based on chance, the lower the degree of risk. After sources of risks are identified and measured, a decision can be made as to how the risk should be handled. A pure risk that is not identified does not disappear, the business merely loses the opportunity to consciously decide on the best technique for dealing with that risk. The process used to systematically manage risk exposures is known as risk management. Some persons use the term risk management only in connection with businesses, and often the term refers only to the management of pure risks. In this sense, the traditional risk management goal has been to minimize the cost of pure risk to the company. But as firms broaden the ways that they view and manage many different types of risk, the need for new terminology has become apparent. The terms integrated risk management and enterprise risk management reflect the intent to manage all forms of risk, regardless of type. International trade transaction is called between countries has features of globalism, cultural gap, long distance and long terms for the transaction. It is riskier than domestic transaction has its specific risks, such as foreign exchange risk and political risk, and requires various active risk management skills. Risks in relation to the international trade transaction are the contract risk, transit risk and payment risk, etc. The risk management in relation to the international trade transaction is to identify and measure these risks. The purpose of this study is to analyse the practical problems and its solution plan by analyzing various cases related to the risk management of bill of lading in the international trade transaction.

• Journal of the Korean Institute of Gas
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• v.14 no.4
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• pp.18-23
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• 2010

After conducting QRA(quantitative risk assessment) for the high pressure urban gas pipelines planned to be installed, RMMs(risk mitigation measures) when the societal risk is outside the acceptable region have been derived in this paper. Also risk reduction rates are calculated for each RMM. As a result of QRA, we find out that damaged distance caused by radiational heat is largely dependent upon the wind velocity and the atmospheric stability. The measure that has the highest risk reduction effect is No. 10 which includes pipeline corrosion monitoring, MOV(motor operated valve) installation and the method to protect pipeline damage caused by third-party mechanical interference, and which shows 75 % of risk reduction effect.

• The Korean Journal of Applied Statistics
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• v.27 no.1
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• pp.71-87
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• 2014

The Bayes premium or the net premium in the credibility theory does not reflect the underlying tail risk. In this study we examine how the tail risk measures can be utilized in determining the risk premium. First, we show that the risk measures can not only provide the proper risk loading, but also allow the insurer to avoid the wrong decision made with the Bayesian premium alone. Second, it is illustrated that the rank of the tail thickness among different conditional loss distributions does not preserve for the corresponding predictive distributions, even if they share the identical prior variable. The implication of this result is that the risk loading for a contract should be based on the risk measure of the predictive loss distribution not the conditional one.

• Journal of Korea Multimedia Society
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• v.18 no.5
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• pp.599-609
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• 2015

As smartphone usage has increased recently, so has smartphone addiction. Many of the smartphone users, however, do not even recognize the risk of smartphone addiction. In this experiment, smartphone users have been categorized into two groups by smartphone addiction measure (S-measure) developed by 2011 National Information Society Agency (NIA): A high risk group and a normal group. The changes of brain waves have been observed when the subjects were watching emotional videos of anger, sadness, happiness, and fear. The results show that the values of FP1 and FP2 (frontal lobe) theta band of the high risk group have been measured to be high, which indicate anxiety disorder. Although happiness and fear videos showed no difference between these groups, sadness and anger videos showed significantly different results for these groups: the brain waves of the high risk group showed higher values than those of the normal group. Therefore, this experiment showed that the high risk group takes feelings of sadness and anger more sensitively than the normal group.

• Proceedings of the Safety Management and Science Conference
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• 2002.11a
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• pp.285-294
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• 2002

The size of state in Korea is like Israel, this country's venture capital is ruled by government. This venture capital's character is below: the concentration on research of venturer affect positively at qualify of products, This paper lies with venture capital's risk character & performance. The results show that Korean venture capitals have lager unsystematic risk than systematic risk, which implies they specialize in specific business and/or regional areas instead of diversification. The Sharpe measure reveals that the performances of Korean venture capitals are very low relative to even the market portfolio(Kospi) and Kosdaq.