• Proceedings of the KSR Conference
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• 2010.06a
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• pp.292-298
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• 2010

Recently, with the beginning of the commercial operation of high-speed railway, there have been a number of changes in track structure fields. Also, it is expected that the development and introduction of new technology will be increased afterwards. However, it accompanies a lot of risk to install new track structures of which performance and safety are not verified on permanent ways with high traffic density. Therefore, to minimize the risk and enhance the adoption of new technology, it is required to develop a systemic verification system for track structure. To do this, in this paper, main contents of a draft of guidelines for track structure verification, and main issues in debate such as criteria and method for verification, test conditions and test periods are discussed. Also, a process to choose a most appropriate one for a specific project out of proven track structures by the above verification system, the selection process by the technical investigation committee and the VE process to analyze the economical and maintenance aspects based on LCC concept in Korea Rail Network Authority is introduced.

• Journal of the Korean Society of Safety
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• v.33 no.6
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• pp.37-41
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• 2018

Process safety technology has developed from qualitative methods such as HAZOP (hazard and operability study) to semi-quantitative methods such as LOPA (layer of protection analysis), and quantitative methods are actively studied these days. Quantitative risk assessment (QRA) is often based on fault tree analysis (FTA). FTA is efficient, but difficult to apply when failure events are not independent of each other. This problem can be avoided using a Markov process (MP). MP requires definition of all possible states, and thus, generally, is more complicated than FTA. A method is proposed in this work that uses an MP model and a Weibull distribution model in order to construct a reliability model for multiple dependent failures. As a case study, a pressure safety valve (PSV) is considered, for which there are three kinds of failure, i.e. open failure, close failure, and gas tight failure. According to recently reported inspection results, open failure and close failure are dependent on each other. A reliability model for a PSV group is proposed in this work that is to reproduce these results. It is expected that the application of the proposed method can be expanded to QRA of various systems that have partially dependent multiple failure states.

• Journal of Korean society of Dental Hygiene
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• v.12 no.5
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• pp.861-870
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• 2012

Objectives : This study has made a comparison of the difference between the periodontal parameter before and after applying dental hygiene process on patients requiring supportive periodontal therapy at a private dental clinic. Methods : The entire process was conducted on 74 patients. As a result of analyzing the difference in periodontal parameters such as PPD>4mm, BOP, and O'Leary Index of 29 patients that has completed 1 circle of dental hygiene process. Results : All periodontal parameters in all subject patients had been significantly reduced(p<0.05). Furthermore, as a result of comparing the periodontal conditions of the smoking group and non-smoking group, complier and non-complier, all parameters were reduced with a significant difference in the non-smoking group and the complier, but the smoking group and the non-complier did not show difference in all parameters. As a result of making an assessment of before and after dental hygiene process according to PRA classifications, high risk group has been generally changed to moderate or low risk group. Conclusions : Accordingly, the supportive periodontal therapy applying dental hygiene process has been shown to be effective. The dental hygiene process in periodontal patients who require continuous management is anticipated to be a very efficient process.

• International Commerce and Information Review
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• v.17 no.3
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• pp.225-250
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• 2015

While strategic alliance of multinational corporation has boost, opportunistic behavior is also increased recently. This study examines the cause of opportunism in strategic alliance by focusing on the development of opportunistic behavior, a process in which resource complementarity and risk perception decides attitudinal direction, ultimately leading to opportunism. Empirical test based on 257 alliance participants shows that risk perception had a greater influence on firms' attitudinal and behavioral directions compared to benefit perception. Notably, relational risk heavily influenced firms' competitive attitude and opportunistic behavior. Finally, the study concludes that firms' competitive and independent attitude caused by risk perception negatively influence alliance outcome. Based on the results, it is drawn that alongside the external tools such as surveillance, control, monitoring or legalistic pleas, management of risk perception during the alliance process has significance influence on the achievement of alliance goals.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.1
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• pp.61-67
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• 2016

The airbag is a widely accepted device for occupant protection in the automotive industry. As the injuries induced by airbag deployment have become a critical issue, revisions to Federal Motor Vehicle Safety Standard (FMVSS) 208 were required to create advanced airbags that can protect occupants of varying statures. In this paper, we developed a new low-risk deployment passenger airbag by adding the Passenger Protection Wrap (PPW). The PPW reduces the cushion impact force to the occupant in order to ensure pressure dispersion. A series of tests were conducted by using FMVSS 208 test procedures to demonstrate the proposed system. It was found that the system not only satisfied the injury criteria of FMVSS 208 but was also effective for protecting passengers of all sizes (male, small female, 3-year-old, 6-year-old).

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.454-459
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• 2003

Feasibility study on large scale projects like an investment on infrastructure development is very important because it provides fundamental data which determine the total investment size and duration. However, previous feasibility studies have a few problems of ambiguous estimation standards, unsystematical estimation methods, and so on. Accordingly, this study intends to regulate tile problems on economic feasibility as well as financial feasibility study which have been considered more critical in recent time, subsequently presents a reform measure. Also, this study identifies predictable risks during the feasibility study, presents a scheme which lets investor and owner control the risk themselves through a process which uses theoretical and political management plans.

• The Research Journal of the Costume Culture
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• v.12 no.6 s.53
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• pp.984-998
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• 2004

The purpose of this study was to analyze contents of clothing product evaluation statements in the internet shopping mall and to discover consumers' recognition and evaluation of it. The data were collected from 151 consumers' statements in the four internet apparel shopping malls and a questionnaire was developed to measure consumers' recognition of clothing product evaluation statements. The questionnaire was administrated 272 consumers over 18 years old. The results of this study were as follows; First, The contents of clothing product evaluation statements in the internet shopping blog, were divided into three categories which were product, service and consumer buying decision process. Product category include evaluation of clothing product, description of difference between real product and product on the screen, and advice of uses. Service category include quickness and kindness in delivery, store preference for good service. For consumer buying decision process, motivation of purchasing, perceived risk, expression of satisfaction from good buying and canvassing for purchasing were included. Second, consumer recognized that clothing product evaluation statements has function of furnishing information, confirmation of purchasing decision, risk reduction of internet shopping, and interesting entertainment. Consumers also were dependent on product evaluation statements for making purchasing decision. And it was trusted by consumers. This recognition & evaluation were correlated with consumer's clothing product knowledge, involvement, risk perception of internet shopping, experiences of internet shopping. Managerial implications are provided for internet shopping mall.

• Journal of the Korean Society of Safety
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• v.24 no.3
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• pp.79-87
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• 2009

The objective of this study is to develop accident scenario models for the risk assessment of railway casualty accidents. To develop these scenario models, hazardous events and hazardous factors were identified by gathering various accident reports and information. Then, the accident scenario models were built up. Each accident scenario model consists of an occurrence scenario model and a progress scenario model. The occurrence scenario refers to the occurrence process of the event before the hazardous event. The progress scenario means the progress process of the event after the hazardous event. To manage a large amount of accident/incident data and scenarios, a railway accident analysis information system was developed using railway accident scenario models. To test the feasibility of the developed scenario models, more than 800 domestic railway casualty accidents that occurred in 2004 and 2005 were investigated and quantitative and qualitative analyses were performed using the developed information system.

• The Korean Journal of Applied Statistics
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• v.25 no.1
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• pp.81-87
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• 2012

A continuous time risk model is considered, where the premium rate is constant and the claims form a compound Poisson process. We assume that an injection is made, which is an immediate increase of the surplus up to level u > 0 (initial level), when the level of the surplus goes below ${\tau}$(0 < ${\tau}$ < u). We derive the formula of the ruin probability of the surplus by establishing an integro-differential equation and show that an explicit formula for the ruin probability can be obtained when the amounts of claims independently follow an exponential distribution.

• Korean Journal of Clinical Pharmacy
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• v.28 no.2
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• pp.124-130
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• 2018

Objective: This study examined the Risk Sharing Agreement (RSA) on pharmaceutical pricing system in Korean national health insurance. Through RSA, the insurer was able to maintain the principles in the price listing process while managing the budget effectively and improving patient access to new drugs. Despite these positive effects, there are still issues raised by some stakeholders, such as lack of transparency in the listing process and doubts about its effectiveness. Therefore, we investigated the impacts of RSA on national health insurance financing and patient access to analyze the effects of RSA. Methods: The impact of RSA was investigated by analyzing the health insurance claims data for 2014~2016. The degree of improvement in patient access was determined by the decreased amount of patients' payment. Results: Results showed that the financial impact of RSA was not significant and patients' access to the new drug greatly improved. Conclusion: These results show that RSA is a good system for improving patient access to new drugs without additional expense on insurance.