• Korean Journal of Clinical Pharmacy
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• v.28 no.1
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• pp.40-50
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• 2018

Objective: This study presented the analysis period, the complexity of combined therapy and comparator choice as the key limitations in the economic evaluation of new drugs, and discussed programs for coping with these limitations. Methods: This study evaluated the post-evaluation, risk-sharing agreement, extra funding program, and flexible incremental cost-effectiveness ratio (ICER) threshold as actions or programs that would increase accessibility to costly new drugs. The study also presented the cases of other countries. The application of the post-evaluation was considered to deal with high uncertainty regarding new drugs. Results: The risk-sharing agreement was introduced in European countries as well as South Korea and has been responsible for the shift from using the financial schemes to outcome-based schemes. The drug funding program has had troubled in securing stable extra funds. The application of higher ICER in the economic evaluation of expensive and innovative oncology drugs was criticized because of the inequity between oncology patients and patients with other diseases. Conclusion: Therefore, introducing and applying actions that would increase the accessibility to costly new drugs in South Korea have been deemed necessary after careful reviews and discussions with various stakeholders (insurer, policy makers, pharmaceutical companies and patients).

• Journal of the Korean Home Economics Association
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• v.23 no.1
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• pp.49-57
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• 1985

The central problem of purchasing houses is choice, which is accompanied by perception of risk. Perceived risk is defined as a risk perceived by a consumer subjectively in choice situations. The components of perceived risk are uncertainty and consequence. There are seven types of perceived risk in purchasing houses. Those are financial risk, functional risk, social risk, psychological risk, physical risk, time risk and future opportunity lost risk. The empirical survey about comsumer's purchasing Public Apartment suggests : 1) In general, rspondents perceive relatively high risk in purchasig Public Apartment. 2) Of seven risk types, financial, functionalm, future opportunity lost, time, and social risk correlate highest with overall perceived risk and explain the variance of it. 3) Physical and psychological risks don't correlate significantly with overall perceived risk. From the findings in empirical analysis, consumers are recommended to device riskreduction activities in purchasing Public Apartment. 1. Active information search is needed in purchasing Public Apartment in order to reduce overall perceived risk. 2. Housing concept should change from ownership to rental thinking. 3. Consumers should be accustomed to Housing Loans by bank. 4. Purchasing goals should be established clearly before purchasing houses. 5. Careful deliberation is required and informations from personal sources are useful.

• Journal of the Korean Society for Railway
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• v.12 no.3
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• pp.342-347
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• 2009

Failure Mode Effects and Criticality Analysis (FMECA) is one of most widely used methods in modern engineering system to investigate potential failure modes and its severity upon the system. While performing FMECA, the experts evaluates criticality and severity of each failure mode and visualize the risk level matrix putting those indices to column and row variable respectably. Which results uncertainty in the result. In order to handle the uncertainty and conclude risk level matrix, this paper proposes a new FMECA procedure using minimal cut set (MCS) and fuzzy theory. Severity is calculated by proposed structural importance while criticality is determined by typical equipment failure rate data from IEEE Std 493. Finally, the risk level is compounded of these indices.

• Geomechanics and Engineering
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• v.24 no.3
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• pp.281-293
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• 2021

Uncertainties in geomechanical input parameters which mainly related to inappropriate data acquisition and estimation due to lack of sufficient calibration information, have led wellbore instability not yet to be fully understood or addressed. This paper demonstrates a workflow of employing Quantitative Risk Assessment technique, considering these uncertainties in terms of rock properties, pore pressure and in-situ stresses to makes it possible to survey not just the likelihood of accomplishing a desired level of wellbore stability at a specific mud pressure, but also the influence of the uncertainty in each input parameter on the wellbore stability. This probabilistic methodology in conjunction with Monte Carlo numerical modeling techniques was applied to a case study of a well. The response surfaces analysis provides a measure of the effects of uncertainties in each input parameter on the predicted mud pressure from three widely used failure criteria, thereby provides a key measurement for data acquisition in the future wells to reduce the uncertainty. The results pointed out that the mud pressure is tremendously sensitive to UCS and SHmax which emphasize the significance of reliable determinations of these two parameters for safe drilling. On the other hand, the predicted safe mud window from Mogi-Coulomb is the widest while the Hoek-Brown is the narrowest and comparing the anticipated collapse failures from the failure criteria and breakouts observations from caliper data, indicates that Hoek-Brown overestimate the minimum mud weight to avoid breakouts while Mogi-Coulomb criterion give better forecast according to real observations.

• Journal of Korea Water Resources Association
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• v.30 no.6
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• pp.691-698
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• 1997

The risk assessment model for dam and levee is applied to a river where two adjacent dams are located in the upstream of the watershed. "A" dam is proven to be safe with 200-year precipitation and unsafe with PMP condition, whereas "B" dam to be safe with 200-year precipitation and PMP condition. The computed risk considering the uncertainties of the runoff coefficient. initial water depth and relevant data of the dam and spillway turn out to be equivalent results in Monte-Carlo and AFOSM method. In levee risk model, this study addresses the uncertainty of water surface elevation by Manning's equation. Monte-Carlo simulation with the variations of Manning's roughness coefficient is calculated by assuming that it follows atriangular distribution. The model can be used for preparing flood risk maps, flood warning systems, and establishing nation's flood disaster protection plan.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.36 no.3
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• pp.43-50
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• 2013

In this paper, the single-period inventory problem, what is called newsboy problem, has been revisited with two different conditions, uncertain supply and risk-averseness. Eeckhoudt et al. [5] investigated the effect of risk-averseness of a newsboy on the optimal order quantity in a stochastic demand setting. In contrary to Eeckhoudt et al. [5] this paper investigates the effect of risk-averseness in a stochastic supply setting. The findings from this investigation say that if ${\alpha}^*$ represents the optimal order quantity without risk-averseness then the risk-averse optimal order quantity can be greater than ${\alpha}^*$ and can be less than ${\alpha}^*$ as well.

• Journal of Environmental Health Sciences
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• v.33 no.1 s.94
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• pp.1-10
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• 2007

This study accomplished to grasp the present condition of HAPs and to examine efficiently carcinogenic and non-carcinogenic health effects through health risk assessment in new apartments from June, 2004 to May,2005. Moreover, we performed uncertainty analysis by Monte-Carlo analysis to control uncertainty of exposure factors. The major results obtained from this study were as follows. Firstly, cancer risk of formaldehyde for male was $1.67{\times}10^{-5}$ in CTE in point estimation. Cancer risk of formaldehyde was showed $2.94{\times}10^{-3}$ in RME that applied worst case used results of 95 percentile in point estimation. It exceeds $10^{-6}$ of guide line in US EPA. Moreover, cancer risks of formaldehyde for female were $3.98{\times}10^{-5}$ in CTE and $3.93{\times}10^{-3}$ RME. Secondly, every hazard index for non-carcinogenic pollutants was less than 1 of permitted standards in CTE. However, in RME of male, hazard indexes of 1,2-Dichloropropane and Toluene were 1.3 and 2.0, respectively. Hazard indexes of 1,2-Dichloropropane and Totuene for female in RME were 1.7 and 2.6, respectively.

• Nuclear Engineering and Technology
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• v.46 no.4
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• pp.481-488
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• 2014

An analysis of the uncertainty quantification related to LBLOCA using the Monte-Carlo calculation has been performed and compared with the tolerance level determined by the Wilks' formula. The uncertainty range and distribution of each input parameter associated with the LOCA phenomena were determined based on previous PIRT results and documentation during the BEMUSE project. Calulations were conducted on 3,500 cases within a 2-week CPU time on a 14-PC cluster system. The Monte-Carlo exercise shows that the 95% upper limit PCT value can be obtained well, with a 95% confidence level using the Wilks' formula, although we have to endure a 5% risk of PCT under-prediction. The results also show that the statistical fluctuation of the limit value using Wilks' first-order is as large as the uncertainty value itself. It is therefore desirable to increase the order of the Wilks' formula to be higher than the second-order to estimate the reliable safety margin of the design features. It is also shown that, with its ever increasing computational capability, the Monte-Carlo method is accessible for a nuclear power plant safety analysis within a realistic time frame.

• Korean Management Science Review
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• v.15 no.2
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• pp.211-227
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• 1998

The process of implementing risk management systems for the organizations in financial service industry can be viewed as a diffusion of innovation since the introduction of the risk management systems changes the decision making process on risks faced by the organizations. The purpose of the reported research is to examine the factors that affect the successful implementation of ALM(asset & liability management) systems, the risk management systems managing interest rate risk. Specifically, this paper presents an investigation of three factors from the diffusion of innovation studies; internal factors, external factors, and time. A field survey was conducted for Korean banks that have implemented ALM systems. The results suggest that the perceived uncertainty of market, system supports, and management supports be most significantly related to the successful implementation of the risk management systems. The findings of the current study also suggest a certain amount of time should be passed to diffuse the risk management systems in organizations.

• Journal of Korea Water Resources Association
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• v.31 no.3
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• pp.337-345
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• 1998

DAMBRK-U model is developed for the evaluation of overtopping risk of dam and levee and for the estimation of uncertainty in floodwave simulation. The original algorithm is revised and expanded to include Monte-Carlo analysis to estimate them. The model is tested by applying to hypothetical channels of widening, uniform and narrowing geometry. Larger variation in discharge and water depth are expected at narrower sections of a river. It is calibrated by applying to the Hantan River, where severe damages from Yunchun dam-break and levee overtopping occurred on July, 1996. Overtopping risk of dam is calculated for various discharge conditions for Yunchun-dam, and that of levee is also calculated by comparing levee height with flood level at Hantan recreation area. Simulation results show that the overflow depth of flood level is 1,266~0.782 m and the overflow risk turns out to be 100%.