• Safety and Health at Work
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• v.8 no.4
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• pp.410-412
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• 2017

Post-traumatic stress disorder (PTSD) is a serious problem not only among workers who experience industrial accidents but also among workers who witness such accidents. Early intervention is needed to prevent prolonged psychological problems. There has been no study conducted regarding the psychological problems of and interventions for bystander workers in Korea. This study introduces the experience of intervention on psychological problems at the Busan Workers' Health Center workers who witnessed their colleagues' death. An investigation and an intervention were conducted according to the Korean Occupational Safety and Health Agency (KOSHA) Guide. In total, 21 individuals including indirect observers showed statistical differences on scores of the Impact Event Scale Revised and the Patient Health Questionnaire 9 after the intervention. Future interventions and research involving a larger sample size over a longer period are needed. The KOSHA Guide could be a useful tool for urgent psychological intervention in the event of major workplace disasters.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.7
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• pp.463-474
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• 2020

This study aims to investigate the impact of COVID-19 pandemic on the stock markets of sixteen countries. Pooled OLS regression, conventional t-test and Mann-Whitney test are used to estimate the results of the study. We construct a weekly panel data of COVID-19 new cases and stock returns. Pooled OLS estimation result shows that the growth rate of weekly new cases of COVID-19 negatively predicts the return in stock market. Next, the returns on leading stock indices of these countries during the COVID-19 outbreak period are compared with returns during the non-COVID period. We use a t-test and Mann-Whitney test to compare the returns. The results reveal that investors in these countries do not react to the media news of COVID-19 at the early stage of the pandemic. However, once the human-to-human transmissibility had been confirmed, all of the stock market indices negatively reacted to the news in the short- and long-event window. Interestingly, we noticed that the Shanghai Composite Index, which was severely affected during the short-event window, bounced back during the long-event window. This indicates that the Chinese government's drastic measures to contain the spread of the pandemic regained the confidence of investors in the Shanghai Stock Market.

• Journal of Biomedical Engineering Research
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• v.29 no.1
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• pp.73-81
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• 2008

The purpose of this study is to observe the brain activity patterns during visual oddball tasks with two difficulty levels by the analysis of high-density event-related potential (ERP). Along with conventional statistical analysis of averaged ERP waveforms, we applied independent component analysis (ICA) for the individual, single-trial analysis and verified its effectiveness. We could identify multiple ERP components such as early visual components (P1, N1), and two components which seem to be important task-related components and showed difficulty-dependent variability (P2, P300). The P2 was found around central region at $180{\sim}220ms$, and the P300 was found globally at $300{\sim}500ms$ poststimulus. As the task became difficult, the P2 amplitude increased, and the P300 amplitude decreased. After single-trial ERPs were decomposed into multiple independent components (ICs), several ICs resulting from P2 and P300 sources were identified. These ICs were projected onto scalp electrodes and the projected ICs were statistically compared according to two task difficulties. For most subjects, the results obtained from single-trial/individual analysis using ICA gave the tendencies of amplitude change that are similar to the averaged ERP analysis for most subjects. The temporal pattern and number of ICs corresponding to ${\mu}$ rhythm was not dependent on the task difficulty. It seems that the motor response was not affected by the task difficulty.

• Korean Journal of Clinical Pharmacy
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• v.31 no.4
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• pp.324-331
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• 2021

To investigate signals of adverse drug reactions of finasteride by using the Korea Adverse Events Reporting System (KAERS) database. This pharmacovigilance was based on the database of the drug-related adverse reactions reported spontaneously to the KAERS from 2013 to 2017. This study was conducted by disproportionality analysis. Data mining analysis was performed to detect signals of finasteride. The signal was defined by three criteria as proportional reporting ratio (PRR), reporting odds ratio (ROR), and information component (IC). The signals of finasteride were compared with those of the other drugs; dutasteride (similar mechanism of action), minoxidil (different mechanism but similar indications for alopecia), silodosin (different mechanism but similar indications for BPH). It was examined whether the detected signals exist in drug labels in Korea. The total number of adverse event-drug pairs was reported 2,665,429 from 2013 to 2017, of which 1,426 were associated with finasteride. The number of investigated signals of finasteride was 42. The signals that did not include in the drug label were 29 signals, including mouth dry, hypotension, dysuria etc. The signal of finasteride was similar to that of dutasteride and silodosin but was different to that of minoxidil. Early detection of signals through pharmacovigilance is important to patient safety. We investigated 29 signals of finasteride that do not exist in drug labels in Korea. Further pharmacoepidemiological studies should be needed to evaluate the signal causality with finasteride.

• Journal of The Korean Society of Agricultural Engineers
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• v.63 no.3
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• pp.87-95
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• 2021

The Doam Lake Watershed is one of Gangwon-do's non-point source management areas. This area has a lot of snowfall in winter, and it is expected that there will be a lot of soil erosion in early spring due to snow melting. In this study, snow melting was monitored in the Doam Lake watershed from February to 3, 2020. It was conducted to analyze the water quality changes by calculating the concentration of non-point source pollution caused by snowmelt, and to compare the concentration of water quality during snowmelt event with rainfall and non-rainfall event. As a result of water quality analysis, Event Mean Concentration (EMC) at the first monitoring was SS 33.9 mg/L, TP 0.13 mg/L, TN 4.33 mg/L, BOD 1.35 mg/L, TOC 1.84 mg/L. At the second monitoring, EMC were SS 81.3 mg/L, TP 0.15 mg/L, TN 3.12 mg/L, BOD 1.32 mg/L, TOC 3.46 mg/L. In parameter except SS, it showed good water quality. It is necessary to establish management measures through continuous monitoring.

• Journal of Service Research and Studies
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• v.13 no.1
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• pp.1-26
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• 2023

We analyze the effects and related factors of Smart Factory adoption. 110 and 325 samples were collected by median-size-industry matching method, respectively, of adopting and non-adopting companies. We use financial statement data (ROA, etc.) from the year before adoption to the fourth year after adoption. Abnormal operating performance and annual abnormal changes are obtained according to event study method, and analyzed by Wilcoxon signed-rank test and t-test. ROA and sales growth rate demonstrate short-term effects after adoption, but not long-term effects. As a result of regression analysis to examine if the three factors of labor intensity, R&D intensity, and prior financial performance have moderating effect, the moderating effect of R&D intensity and prior financial performance is confirmed. In addition, we perform regression analysis to confirm performance effects of early and late adoptions and whether prior financial performance and organization size have moderating effect. It is confirmed that the later the time of adoption, the greater the effect of adoption in the long term and the moderating effect of prior financial performance and organization size is confirmed.

• Journal of Korean Society of Forest Science
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• v.96 no.1
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• pp.21-28
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• 2007

This study was conducted to investigate how the qualities of the stream water vary during the event in the regrowth and rehabilitation catchments in Yangju, Gyeonggido, from June to September 2005. During the observation periods, we sampled the stream water continuously by an auto-sampler (ISCO, 6712FR). The sampled waters were analyzed for suspended solid concentration, electrical conductivity and pH. The suspended solid concentration during the event increased concurrently with the stream flow. The peak of suspended solid concentration usually precedes the peak flow. The maximum value of suspended solid concentration was 420.89 mg/l in the event 1 at the regrowth catchment. Among the events simultaneously sampled at both catchments, the maximum values of suspended solid concentration were 212.8 mg/l and 58.24 mg/l in the event 3 at the regrowth and rehabilitation catchment respectively. The maximum value of EC in each event showed in the early stage of rising limb. EC decreased during the rising limb, and then showed minimum value at peak flow. EC gradually increased to pre-event value after minimum one. pH varied in similar pattern with EC. The maximum value of suspended solid concentration during each event was 2.8 to 4.3 times higher at the regrowth catchment than at the rehabilitation catchment. And the EC during each event was higher at the regrowth catchment than at the rehabilitation catchment. This results indicate that a disturbed forest soil during clear cutting at regrowth catchment still has been unstable.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.353-353
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• 2017

Rice yield of South Korea in 2015 was the highest of the last 30 years. It is important issue to establish food policy whether the historically highest yield in 2015 can be continued or just one-off event. Therefore, it is necessary to understand whether such a high yield as 2015 will be reoccurred. The aim of this study was to find out what climatic factor affect rice yield and how often these climatic factor could occur. For this study, the yield monitoring data from National Institute of Crop Science, Rural Development Administration and the meteorological data provided by Korea Meteorological Administration are used to identify the weather conditions could cause high yield, and how often these conditions occurred in the past. Our results indicated that such as high yield as 2015 could occur only when the mean sunshine hours of July and the mean sunshine hours from the end of August to early September was more than 5.1 hours and 6 hours, respectively. Mean sunshine hour of July may be related to grain number. The mean sunshine hour from the end of August to early September was presumed to relate to grain filling ratio. The relationship between monthly mean temperature and yield or yield component was not clear in this study. In this study, any cycle of high weather condition was not found. Therefore, the probability of high yield weather condition was expressed by frequency. The frequency of the sunshine hour, could make high yield, were 8/35 (23%) over the past 35 years. And the frequency of two years consecutive sunshine hour condition, which could cause high yield, was 1/35 (2.9%). The frequency of recurrence of sunshine hour making high yield within the next 5 years or 10 years after high yield weather condition were 4/35 (11.4%). After all, the high yield as much as yield of 2015 could not be one-off event. But it was not also consecutive event.

• The Journal of the Petrological Society of Korea
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• v.25 no.4
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• pp.389-400
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• 2016

The study area, which is located in the southeastern part of the Jirisan province of the Yeongnam massif, Korea, consists mainly of the Precambrian Sancheong anorthosite complex and the Jirisan metamorphic rock complex, the Mesozoic granitoids which intruded them. Several fracture sets with various geometric indicators, which determine their relative timing and shear sense, are well observed in the Sancheong anorthosite complex. The aim of this study is to determine the development sequence of extension fractures, the movement sense and development sequence of shear fractures in the Sancheong anorthosite complex on the basis of detailed analysis of their geometric indicators. This study suggests fracture system of the Sancheong anorthosite complex was formed at least through five different fracturing events, named as Dn to Post-Dn+3 phases. (1) Dn phase: extension fracturing event of NNW trend. The fracture set experienced the reactivations of dextral ${\rightarrow}$ sinistral shearing with the change of stress field afterward. (2) Dn+1 phase: extension fracturing event of (N)NE trend. The fracture set experienced the reactivations of sinistral ${\rightarrow}$ sinistral ${\rightarrow}$ dextral. (3) Dn+2 phase: extension fracturing event of NW trend. The fracture set experienced the activated of dextral shearing. (4) Dn+3 phase: extension fracturing event of N-S trend. (5) Post-Dn+3 phase: extension fracturing event of (E)NE trend. Dn deformation formed during the early Songnim orogeny. Dn+1 deformation formed during the late Songnim orogeny. Dn+2 deformation formed during the Daebo orogeny. Dn+3 deformation formed during the Bulguksa orogeny.

• Journal of Plant Biotechnology
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• v.38 no.2
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• pp.125-129
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• 2011

Environmental risk assessment (RA) is essential prior to the environmental release of GM crops. RA, however, costs at least 7 to 15 million US dollars and requires several years to complete field tests. Therefore, it is strongly suggested that developers of GM crops must consider all criteria for RA at the beginning stage of the development if it aims for commercialization. Previous review papers have pointed out that the "death valley" for the commercialization of GM crops is the screening stage of early GM events since many candidates are given up due to insufficient data on the molecular characterization of a GM event such as inserted gene's copy number, position of inserted site of a chromosome, flanking sequence of recombinant T-DNA, rearrangement of chromosome, and knock out of endogenous gene of host plant. Recently, Rural Development Administration (RDA) in South Korea has launched a Grand National Project named as "Next Generation of BioGreen 21 Project" from 2011 to 2020 and research funding for the development of global GM crops has been allocated to accelerate the commercialization of GM crops. In this regard, I strongly suggest that researchers involved in the development of GM crops for commercialization must conduct RA by themselves at the screening stage of pre-GM event based on the data for molecular characterization.