• Nuclear Engineering and Technology
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• v.53 no.10
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• pp.3298-3313
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• 2021

The objective of this study is to estimate the occurrence probabilities of severe accident phenomena based on a fuzzy elicitation technique. Normally, it is difficult to determine these probabilities due to the lack of information on severe accident progression and the highly uncertain values currently in use. In this case, fuzzy set theory (FST) can be best exploited. First, questions were devised for expert elicitation on technical issues of severe accident phenomena. To deal with ambiguities and the imprecision of previously developed (reference) probabilities, fuzzy aggregation methods based on FST were employed to derive the occurrence probabilities of severe accidents via four phases: 1) choosing experts, 2) quantifying weighting factors for the experts, 3) aggregating the experts' opinions, and 4) defuzzifying the fuzzy numbers. In this way, this study obtained expert elicitation results in the form of updated occurrence probabilities of severe accident phenomena in the OPR-1000 plant, after which the differences between the reference probabilities and the newly acquired probabilities using fuzzy aggregation were compared, with the advantages of the fuzzy technique over other approaches explained. Lastly, the impact of applying the updated severe accident probabilities on containment integrity was quantitatively investigated in a Level 2 PSA model.

• Journal of the Korean Statistical Society
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• v.33 no.1
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• pp.35-58
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• 2004

For fixed positive integers and $\textit{k}\;(n\;{\geq}\;{\textit{k}}\;+\;2)$, the exact probability distributions of non-overlapping and overlapping patterns of two failures separated by (i) exactly $textsc{k}$ successes, (ii) at least $\textit{k}$ successes and (iii) at most $\textit{k}$ successes have been obtained for Bernoulli independent and Markov dependent trials by using combinatorial technique. The waiting time distributions for the first occurrence and the $r^{th}$ (r > 1) occurrence of the patterns have also been obtained.

• Journal of the Korean earth science society
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• v.30 no.5
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• pp.598-604
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• 2009

Three species of Pseudolarix including P. japonica, P. sp. A, and P. sp. B, all belonging to Pinaceae, are systematically described from the Middle Miocene Duho Formation of the Yeonil Group based on the detached seminiferous scales. The presence of Pseudolarix in the Yeonil flora indicates that various kinds of Pinaceae did flourish during the Middle Miocene. The occurrence of Pseudolarix is the first record in the Korean Tertiary flora.

• Journal of the korean veterinary medical association
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• v.20 no.4
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• pp.239-243
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• 1984

The occurrence of left displacement of the abomasum (LDA) were studied in 32 dairy cows of surrounding pastures in Gim-po contry of Kyung-Gi Do through year. The results observed were as follows; 1. The rate of occurrence by LDA were the most in the first

• Korean journal of applied entomology
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• v.34 no.4
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• pp.295-299
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• 1995

This study was conducted to find the control methods, status of overwintering and seasonal occurrence of Erioccoccus largerstroemiae on persimmon trees in Ch'ondo area, Kyongbuk province in Korea. Usually, overwintering eggs were sheltered in bark, among them the rate of alive eggs was 28.7%. The activiation of garpe-myrtle scale showed from late April, and they have three generations per year. The first occurrence of larval stage of Erioccoccus largerstroemiae starts from late June to early July, the second occurrence begins from middle August to late August, and from late June to early July, the second occurrence begins from middle August to late August, and from middle September to late September is the third, thus, three peaks of occurrence revealed in early July middle August, and late September respectively. Average number of eggs conceived in female adult was 229.3. Spray effect of chemical control showed as follows; lime sulfur with tow applications of pesticides (late June, late August) at 97.8%, machine oil with tow applications of pesticides (late June, late August) at 96.8%. And during the growing period, the spray results using three applications of pesticide only (late June, late August, amid September) showed 77.2% in field condition.

• The Journal of Fisheries Business Administration
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• v.52 no.4
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• pp.29-43
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• 2021

This study investigated whether there is a correlation between the occurrence of hazardous substances such as vibrio, norovirus, radioactivity, shellfish posion, hepatitis A, etc. and media reports, and whether the occurrence of hazardous substances and media reports affect the production, distribution and consumption of aquatic products. The main research results are as follows. First, it can be seen that there is a difference in the relationship between the occurrence of hazardous substances and media reports according to hazardous substances. Second, it suggests seen that the occurrence of hazardous substances and media reports can have a negative effect on the production and the prices of aquatic products. Third, it was found that the occurrence and reporting of hazardous substances had different effects on the distribution margin of aquatic products due to the complexity and rigidity of the distribution structure. Fourth, consumers feel a threat to aquatic products safety and significantly reduce consumption when hazardous substances occur. There is a possibility that concerns about one item may lead to a decrease in consumption of domestic and imported aquatic products that are not related at all to the occurrence of hazardous substances. In conclusion, aquatic products are exposed to various hazardous substances such as vibrio, norovirus, radioactivity, shellfish posion, and hepatitis A. It was found that the occurrence of hazardous substances and its media reports could cause damage to the fishery sector.

• Animal Systematics, Evolution and Diversity
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• v.29 no.3
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• pp.253-258
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• 2013

Two specimens of Chromis albicauda were collected from Jeju Island, Korea. The species is most similar to C. analis, but is distinguishable by the presence of a white caudal fin when alive, 4-5 scale rows on the anterior portion of the preorbital, and a blackish blotch around anal opening. The results of a molecular analysis based on mitochondrial DNA 16S rRNA sequences confirm that the two individuals are not C. analis but C. albicauda as the genetic distance between the two species is 0.044. A comparison of the two individuals of C. albicauda with yellow chromis shows that none of the previously reported yellow chromis is C. analis, but rather they are C. albicauda. Herein, we suggest the new Korean name "Huin-ggo-ri-no-rang-ja-ri-dom" for C. albicauda.

• Clinical and Experimental Vaccine Research
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• v.12 no.2
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• pp.87-96
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• 2023

The fast development of vaccines against the novel coronavirus disease is among the most critical steps taken to control this potentially fatal viral disease. Like other vaccines, the coronavirus disease 2019 (COVID-19) vaccines can also cause unwanted reactions. Erythema multiforme (EM) is among the oral mucocutaneous side effects of COVID-19 vaccines. This study aimed to comprehensively review the reported cases of EM since the global onset of COVID-19 vaccination. Data from 31 relevant studies regarding the type and dose of COVID-19 vaccines administered, time of initiation of symptoms, age, and gender of patients, site of involvement, patients' medical history, and treatment options were extracted. In total, 90 patients were identified with EM as a side effect of COVID-19 vaccination across studies. EM had the highest frequency after receiving the first dose of mRNA vaccines in older individuals. The first symptoms of EM appeared in less than 3 days in 45% and after 3 days in 55% of patients. EM is not a common side effect of COVID-19 vaccination, and fear of its occurrence should not impede vaccination.

• Clinical and Experimental Pediatrics
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• v.59 no.2
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• pp.74-79
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• 2016

Purpose: Febrile seizure, the most common type of pediatric convulsive disorder, is a benign seizure syndrome distinct from epilepsy. However, as epilepsy is also common during childhood, we aimed to identify the prognostic factors that can predict epilepsy in children with febrile seizures. Methods: The study comprised 249 children at the Korea University Ansan Hospital who presented with febrile seizures. The relationship between the subsequent occurrence of epilepsy and clinical factors including seizure and fever-related variables were analyzed by multivariate analysis. Results: Twenty-five patients (10.0%) had additional afebrile seizures later and were diagnosed with epilepsy. The subsequent occurrence of epilepsy in patients with a history of febrile seizures was associated with a seizure frequency of more than 10 times during the first 2 years after seizure onset (P<0.001). Factors that were associated with subsequent occurrence of epilepsy were developmental delay (P<0.001), preterm birth (P =0.001), multiple seizures during a febrile seizure attack (P =0.005), and epileptiform discharges on electroencephalography (EEG) (P =0.008). Other factors such as the age at onset of first seizure, seizure duration, and family history of epilepsy were not associated with subsequent occurrence of epilepsy in this study. Conclusion: Febrile seizures are common and mostly benign. However, careful observation is needed, particularly for prediction of subsequent epileptic episodes in patients with frequent febrile seizures with known risk factors, such as developmental delay, history of preterm birth, several attacks during a febrile episode, and epileptiform discharges on EEG.

• Korean Journal of Agricultural Science
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• v.50 no.4
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• pp.723-734
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• 2023

Erwinia pyrifoliae, which causes black shoot blight in apple and pear trees, was first identified in Korea in 1995. Extensive measures are typically used to control the disease by eradicating trees in diagnosed orchards, owing to the detrimental impact of the disease on apple and pear production. However, despite governmental efforts, the disease has continuously spread. In this study, we analyzed the current status of the black shoot blight occurrence in apple and pear orchards between 1995 to 2022. Our findings reveal that over the past 28 years, black shoot blight has occurred in 26 cities and districts across five Korean provinces. The affected regions are predominantly concentrated in the northern part of Korea, including the Gangwon and Gyeonggi provinces. Furthermore, black shoot blight has gradually expanded to the northern provincial regions of Chungbuk, Chungnam, and Gyeongbuk, which are centrally situated in Korea. Furthermore, the occurrence pattern of black shoot blight differed between apple and pear orchards; in apple orchards, black shoot blight occurred consistently each year, with a sudden increase in cases in 2020; however, in pear orchards, it has considerably decreased since 2007. To the best of our knowledge, this is the first comprehensive report on the occurrence of black shoot blight in apple and pear trees in 28 years, and the results will provide valuable insights for future disease management strategies.