• Transactions of the Korean hydrogen and new energy society
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• v.31 no.1
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• pp.73-81
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• 2020

For the fault tree analysis (FTA) analysis of the packaged hydrogen filling station, the composition of the charging station was analyzed and the fault tree (FT) diagram was prepared. FT diagrams were created by dividing the causes of events into external factors and internal factors with the hydrogen event as the top event. The external factors include the effects of major disasters caused by natural disasters and external factors as OR gates. Internal factors are divided into tube tailer, compressor & storage tank, and dispenser, which are composed of mistakes in operation process and causes of accidents caused by parts leakage. In this study, the purpose was to improve the hydrogen station. The subjects of this study were domestic packaged hydrogen stations and FTA study was conducted based on the previous studies, failure mode & effect analysis (FMEA) and hazard & operability study (HAZOP). Top event as a hydrogen leaking event and constructed the flow of events based on the previous study. Refer to "Off shore and onshore reliability data 6th edition", "European Industry Reliability Data Bank", technique for human error rate prediction (THERP) for reliability data. We hope that this study will help to improve the safety and activation of the hydrogen station.

• Nuclear Engineering and Technology
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• v.47 no.1
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• pp.59-65
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• 2015

Background: After the Fukushima accident, the importance of hazard analysis for extreme external events was raised. Methods: To analyze typhoon-induced hazards, which are one of the significant disasters of East Asian countries, a statistical analysis using the extreme value theory, which is a method for estimating the annual exceedance frequency of a rare event, was conducted for an estimation of the occurrence intervals or hazard levels. For the four meteorological variables, maximum wind speed, instantaneous wind speed, hourly precipitation, and daily precipitation, the parameters of the predictive extreme value theory models were estimated. Results: The 100-year return levels for each variable were predicted using the developed models and compared with previously reported values. It was also found that there exist significant long-term climate changes of wind speed and precipitation. Conclusion: A fragility analysis should be conducted to ensure the safety levels of a nuclear power plant for high levels of wind speed and precipitation, which exceed the results of a previous analysis.

• Korean Journal of Culture and Social Issue
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• v.11 no.1
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• pp.85-108
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• 2005

This study was to conceptualize Palzha and investigate Palzha inference as mode of self-view. In general, people would like to attribute their unhappy and unfortunate life events or histories to Palzha which is given by the supernatural being. According to analysis of interviews and open-ended responses concerning on Plazha, Palzha indicated 'luck', 'uncontrollable situation', or 'fate' given by the supernatural being. In study 2, we conducted an analysis of the relationship between locus of control belief and Palzha attribution. More having external control belief, more tending to attributing the rugged life events or histories, and unexpected fortunate events to Palzha. Consequently, Palzha as mode of self-view on everyday events or life-events indicated it is likely to be another dimension of attribution on negative as well as positive life events in Korean culture.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2005.05a
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• pp.23-27
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• 2005

Humans perceptually segment events, but models that predict where events will be segmented are limited. Developing a detailed model may be hard because of the overlapping quality of events (i.e., one can smile and walk at the same time, but the endpoint of each event can be different). However, some aspects of events appear to be universally represented in the world's languages. For example, path, the trajectory of an object's movement, is one of the most universally encoded event features. Although it is generally encoded in the prepositions of English (e.g., up), in other languagesit is encoded in the verbs (e.g., descendere). Linguistic universals may represent basic levels of event perception. Here we consider how one of these, path, might be parsed. Because the spatiotemporal projection of paths to an observation point is similar to the spatial projection of objects, we tested the hypothesis that path segmentation and object segmentation would be based on similar image properties, such as discontinuities in orientation.

• Language and Information
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• v.2 no.1
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• pp.157-176
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• 1998

This paper claims that beneficiary adjuncts are best analyzed as involving external predication in a version of grammatical framework called Head-driven Phrase Structure Grammar. This paper also claims that verbal catefories need to include the attribute INDEX among their semantic components in order to account for the external predication proposed in this paper. This paper distinguishes between recipient and beneficiary reles and assumes that the former is a semantic argument of a verb-type relation and that the latter is an adjunct which makes a semantic contribution as a modifier. This approach achives a unified analysis of modification phenomena of nominal and verbal categories and it can also accomodate Parson's(1990) idea that a verbal category denotes a set of events, not just an event.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.13 no.2
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• pp.87-98
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• 2015

Safety assessments of geological radioactive waste disposal systems, need to consider the abnormal scenario in which a system is impacted by external events in addition to a reference scenario. In this study, the characterization and prediction of an earthquake as an external event which will impact disposal systems were conducted probabilistically and statistically for the safety assessment. The domestic earthquake data were analyzed, and the prediction methodologies of the earthquake were suggested with a computational example. From the results, the earthquake occurrence rates in Korea ranged from 0.4 /yr to 36.2 /yr depending on the data set and the completeness magnitude. From a conservative point of view, the earthquake occurrence rate in the disposal system was suggested as 5.4×10^-4 /yr considering the area of the disposal system. At that time, the completeness magnitude of an earthquake was 2.3. This study will be followed by an appraisal of impacts associated with external events on the geological disposal system, and it will contribute to improvements in reliability of the safety assessment.

• Journal of Convergence for Information Technology
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• v.12 no.5
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• pp.107-115
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• 2022

The purpose of this study is to identify the drivers of supply chain vulnerability and internal/external disruptive events and to verify the moderating effect of SCRM to mitigate negative disruption impacts. The analysis results of 182 SMEs are as follows. First, SC vulnerability proceeded from excessive efficiency. Second, the probability and severity of internal factors were higher than that of external factors. In particular, the priority of responding to risks arising from the supply chain process was higher than the value chain within the firm. Finally, the higher the level of risk management in the supply chain, the more positively the negative disruption impact was mitigated. This study is valuable in providing practical clues to the decision-making of a firm's managers and policymakers responding to supply chain risks.

• Radiation Oncology Journal
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• v.31 no.4
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• pp.234-238
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• 2013

Purpose: Esophageal tolerance is needed to guide the safe administration of stereotactic radiosurgery (SRS). We evaluated comprehensive dose-volume parameters of acute esophageal toxicity in patients with spinal metastasis treated with SRS. Materials and Methods: From May 2008 to May 2011, 30 cases in 27 patients with spinal metastasis received single fraction SRS to targets neighboring esophagus. Endpoints evaluated include length (mm), volume (mL), maximal dose (Gy), and series of dose-volume thresholds from the dose-volume histogram (volume of the organ treated beyond a threshold dose). Results: The median time from the start of irradiation to development of esophageal toxicity was 2 weeks (range, 1 to 12 weeks). Six events of grade 1 esophageal toxicity occurred. No grade 2 or higher events were observed. $V_{15}$ of external surface of esophagus was found to predict acute esophageal toxicity revealed by multivariate analysis (odds radio = 1.272, p = 0.047). Conclusion: In patients with spinal metastasis who received SRS for palliation of symptoms, the threshold dose-volume parameter associated with acute esophageal toxicity was found to be $V_{15}$ of external surface of esophagus. Restrict $V_{15}$ to external surface of esophagus as low as possible might be safe and feasible in radiosurgery.

• The Journal of Korean Medicine
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• v.29 no.5
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• pp.41-51
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• 2008

Objective : To observe the efficacy and safety of CheungYeolYiSeup-tang and Hwangbaek external dressings on dampness-heat pattern atopic dermatitis(AD) in a non-comparative study. Methods : 10 patients with AD were included for 4 weeks of treatment. Efficacy and safety assessment included the scoring atopic dermatitis index(SCORAD), typical signs and symptoms of AD, results of some laboratory tests related to toxicity, and the incidence of adverse events. Results : Improvements in efficacy parameters were observed and produced no significant changes in laboratory tests related to toxicity in these patients. Their SCORAD results significantly decreased after 4weeks(P value<.01, according to the Wilcoxon sum of ranks test). Similarly, significant reductions from baseline in subjective pruritus scores and (P value<.05 by the Wilcoxon sum of ranks test) and the mean average of individual signs and symptoms of AD were reported after 4 weeks(P value<.05, P<0.01 by the Wilcoxon sum of ranks test). There were no significant changes in eosinophil, neutrophil, lymphocyte, immunoglobulin E and ESR in blood serum by paired ttest. Conclusion :CheungYeolYiSeup-tang administration and Hwangbaek external dressings are an effective and safe treatment for the management of dampness-heat pattern atopic dermatitis.

• Journal of Preventive Medicine and Public Health
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• v.46 no.5
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• pp.261-270
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• 2013

Objectives: This study investigated the socio-demographic characteristics and medical causes of death among meteorological disaster casualties and compared them with deaths from all causes. Methods: Based on the death data provided by the National Statistical Office from 2000 to 2011, the authors analyzed the gender, age, and region of 709 casualties whose external causes were recorded as natural events (X330-X389). Exact matching was applied to compare between deaths from meteorological disasters and all deaths. Results: The total number of deaths for last 12 years was 2 728 505. After exact matching, 642 casualties of meteorological disasters were matched to 6815 all-cause deaths, which were defined as general deaths. The mean age of the meteorological disaster casualties was 51.56, which was lower than that of the general deaths by 17.02 (p<0.001). As for the gender ratio, 62.34% of the meteorological event casualties were male. While 54.09% of the matched all-cause deaths occurred at a medical institution, only 7.6% of casualties from meteorological events did. As for occupation, the rate of those working in agriculture, forestry, and fishery jobs was twice as high in the casualties from meteorological disasters as that in the general deaths (p<0.001). Meteorological disaster-related injuries like drowning were more prevalent in the casualties of meteorological events (57.48%). The rate of amputation and crushing injury in deaths from meteorological disasters was three times as high as in the general deaths Conclusions: The new information gained on the particular characteristics contributing to casualties from meteorological events will be useful for developing prevention policies.