• Economic and Environmental Geology
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• v.28 no.6
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• pp.571-577
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• 1995

Several acid-sulfate clay deposits associated with silicic magmas occur in the Haenam area of the southwestern part of Korea. Geology of the studied area consists of tuffs, granitic rocks, quartz porphyry, rhyolite, andesite and sedimentary rocks. The granitic rocks and quartz porphyry intruded tuffs and sedimentary rocks. The rhyolite and tuffs around the mines have undergone hydrothermally weak or strong alteration. Gold contents with major and trace elements have been determined for a total of sixty-seven specimens of fresh igneous rocks, wall rocks and minerals such as dickite and alunite by graphite furnace atomic absorption spectrometer and inductively coupled plasma. Gold is enriched in the alunite vein and the silicified zone, but is depleted in dickites and hydrothermally altered rocks with dickite of the Seongsan deposit. Gold is especially concentrated near the faults or conjunction area of two faults. High content of gold is shown in the mineral assemblages of alunitequartz- pyrite in the alunite vein and silicic zone of the Seongsan deposit compared with that of minerals and rocks from another deposits distributed in the studied area. Gold content in tuffs and dickites with pyrite is generally low. Gold content in silicified tuff tends to show positive correlations with content of As, Hg and Sb. Variation trends of Cd, Hg and Sb are similar to those of gold content. From the result of gold content variations, gold may be transported and concentrated by mineralizing solutions ascending along the cracks like fault. Therefore, it is important to survey alunite vein and silicified zone at the conjunction of faults, and to analyze pathfinder elements such as As, Hg and Sb for geological and geochemical exploration of gold in the studied deposits.

• Korean Security Journal
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• no.40
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• pp.87-108
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• 2014

In this study, we tried to find ways to minimize the negative effects of workplace bullying by analysing how workplace bullying affects private security guard's job attitude. The results of survey are as follows. First, as the result of analysis how the guard's workplace bullying affects job satisfaction, one of the job attitude, it showed that relational aggression and workplace bullying have a negative effect on their job satisfaction. In other words, job satisfaction decreases as relational aggression and workplace bullying increase. Second, as the result of analysis how the guard's workplace bullying affects their turnover intention, we found that relational aggression and workplace bullying have an effect on turnover intention, especially, relationally workplace bullying has a more effect on their turnover intention than relational aggression, which Is somewhat different from other studies. Study shows that workplace bullying can cause the guard's negative respond and behavior on their job satisfaction, they have to consider transferring another job. Therefore, increasing their job satisfaction and decreasing turnover intention are very important as we are exposed to crimes these days. In this study, we have come with following solutions. First, to increase job satisfaction against workplace bullying, we have to raise the efficiency of their human resources and reduce work ambiguity of actual work burden caused by positive organizational atmosphere and clear responsibility. Second, it is needed to promote personnel exchange between departments and form partnership through regular meetings by targeting common goals to concentrate same interests. At the same time, we have to improve the guard's welfare and working environment by introducing psychological counselling to the victims of bullying.

• The Journal of the Korea Contents Association
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• v.20 no.11
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• pp.170-183
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• 2020

This study sought to investigate the relationship between emotional labor and commitment to organization of flight attendants as a way to identify solutions for service quality issues attributed to reduced commitment. It was also intended to determine the relational routes in terms of the effects of social support as a supplementary factor in reduced air service quality. A survey was conducted from January 2020 for about one month and a total of 426 copies were used in the final analysis. SPSS 23.0 and AMOS 23.0 statistical programs were used for the data analysis. The results are as follows. First, the emotional labor of flight attendants showed a negative impact on the social support including support from peers, families, and team leaders. Second, support from peers and team leaders had a positive impact on commitment to organization. Third, the emotional labor of flight attendants showed a negative impact on their commitment to organization. Fourth, support from peers and team leaders were found to have a mediated effect on the relationship between emotional labor and commitment to organization.

• Korean Journal of Construction Engineering and Management
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• v.18 no.2
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• pp.38-48
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• 2017

Finding causes of workers' unsafe behaviors is important to prevent construction accidents because 80 percent of accidents occur by workers' unsafe behaviors. In this regard, this research aims to investigate possible reasons of workers' unsafe behaviors based on workers' cognitive process model using System dynamics. This study is based on two ways of workers' cognitive process which are in relation to hazard perception and failure of hazard perception. Based on existing literature, causal loops for workers' cognitive process are developed to explain workers' habituation by staying out of accidents, safety learning by experience, failure of hazard perception, and attitude change by accidents. The interactions between the developed loops provide managerial insights to reduce workers' unsafe behaviors from a safety manager's perspective including increasing the probability of workers' hazard perception through knowledge management, maintaining workers' positive attitude toward safety, and controlling first-line supervisors to eliminate workers' unsafe behavior. The research allows us to better understand the causes and solutions of workers' unsafe behaviors in workers' cognitive perspectives.

• Journal of the Korean Wood Science and Technology
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• v.44 no.5
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• pp.743-749
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• 2016

The concentration control of wood preservatives is necessary to produce a preservative treated wood having a uniform quality. Concentration measurement method of wood preservatives to be easily used in the field has not been developed yet. This study examined the way to estimate the concentration from turbidity of ACQ wood preservative that can be relatively easily measured by using a portable turbidity meter. The addition of phosphoric acid solution in an alkaline ACQ solution having a very low turbidity is created a suspension of the white substance and the turbidity suddenly increased. The optimum amount of addition of the phosphoric acid solution is until the pH of ACQ solution reaches 7, the turbidity of the ACQ solution reaches maximum value. Excessive addition of the phosphoric acid solution results in a turbidity decrease with acidification of the ACQ solution. Also ACQ solution becomes transparent. The high significance was recognized with positive correlation between the concentration and the turbidity of the ACQ solution. From the t-test, The significant difference between the actually measured concentrations and the concentrations predicted by the regression equation for industrial ACQ solutions was not recognized. Thus, it was possible to know that concentration prediction and control of industrial ACQ solution using the turbidity and a regression equation. Therefore, using the regression equation and turbidity is expected to be able to management the concentration of ACQ solution in the industrial field.

• Journal of the Korean Chemical Society
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• v.46 no.3
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• pp.287-295
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• 2002

In this study, the effects of a self-assessment on the students' science concept understanding and science-related attitudes were investigated. Student's perceptions towards the self-assessment were also examined. Five classes from a middle school in Gyunggi Province were chosen. Two of those classes were assigned to the control group that no self-assesment tool was applied to and the other 3 classes were assigned to the experimental group which a self-assess-ment tool developed for this study was applied to. The experimental group was further divided into two groups for imple-ment of two kinds of programs. One experimental group was provided some feedback such as solutions to problems and the other was not provided any type of feedback. The tests of science-related attitudes were administered before and after the instruction period. The science concepts understanding test was done only after the instruction. The results of this study were as follows. There were significant differences between the experimental group and control group in under-standing of scientific concepts. The enhancement of science-related attitudes was also higher for the experimental group. Providing feedback to students was more effective in the improvement of students' science-related attitudes. However, there were no significant differences in understanding of scientific concepts in relation to the feedback in experiment groups. From the above results, it was acknowledged thet self-assessment applied to the middle school science class showed considerably positive influences on the improvements of the understanding of scientific concepts and science-related attitudes.

• Food Science and Preservation
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• v.11 no.3
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• pp.331-335
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• 2004

This study was carried out to improve quality of minimally processed lettuce with various treatments. The treatments for preventing enzymatic browning were using different chemical immersion solutions and controlling microbial growth were using chlorine, electrolyzed water, and organic acid. The solution with ascorbic acid 1$\%$ and citric acid 1 $\%$ showed a positive effect on antibrowning of minimally processed lettuce. In the inhibition of microorganisms growth, 200 ppm NaCIO solution was more effective than fermented pollen solution and Na-dichloroisocyanurate solution. In electrolyzed water system, no-diaphragm system showed inhibitory effect of microorganisms growth. Also, total microorganisms count of minimally processed lettuce with ascorbic acid and citric acid solution was lower by about 4 log cycle after 4 days storage at l0$^{\circ}C$.

• Journal of Environmental Policy
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• v.12 no.1
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• pp.75-100
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• 2013

Health damages such as pneumoconiosis and kidney damage, caused by environmental hazardous factors are being reported in health impact assessment conducted on environmentally vulnerable areas, including cement factories and refineries. Current legal system for relieving the environmental victims is not effective enough because the environmental health act does not specify the environmental hazardous factors to be considered for the relief. The aim of this study is to examine the problems of the existing system by making empirical analysis on health damages and afflicted people as well as on cases when afflicted people were able to be covered by remedy system. The results show that, insufficiencies of the relief system are due to the following reasons: First, current Environmental Health Act does not act well as a remedy system. Second, due to its unique nature of environmental health damage, it is hard to identify and prove the cause of health damage and unlawful actions of violators in the process of environmental dispute conciliation and lawsuits against polluters. This paper suggests following solutions on above mentioned problems. First, in defining the range and definition of environmental diseases, negative system should be used alongside with the current positive system. Second, we suggest adding the nature of public law to relief system, in order to ease the legal burden of proof. Third, in case when it is hard to identify the polluters and one cannot expect reliefs for their damage, it is possible to elevate the effectiveness of the relief measure by expanding scope of the search for possible environmental hazardous factors that caused the health damage. It is urgent to improve the relief system so as to secure the environmental rights of Koreans.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.11
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• pp.1351-1357
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• 2007

"Hae-Songi" mushroom is a kind of Hypsizigus marmoreus, one of the edible mushrooms. Powder and hot water extracts of the mushroom fruit-body were investigated for their proximate composition, amino acid contents, ${\beta}-glucan$ contents, total phenolic contents and antioxidant activity. The measured antioxidant activity included free radical scavenging activity against DPPH, reducing power $Fe^{2+}$ chelating ability and SOD activity. Mushroom extracts exhibited in vitro antioxidant activity. This mushroom contained high protein (29%, total amino acid contents 204.86 mg/g), free amino acids (46.53 mg/g) and ${\beta}-glucan$(0.11%). At a concentration of 1% extracts solutions (w/v) according to different extraction times, DPPH free radical-scavenging activities were found to exhibit $89%{\sim}92%$ inhibition. Positive correlations $(R^2=0.9901{\sim}0.7424)$ were found between total phenolic content in the mushroom hot water extracts and their antioxidant activity. In this study, it is demonstrated that "Hae-Songi" mushroom may possess potential for use as a health food, due to theirantioxidant capacity.

• Analytical Science and Technology
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• v.9 no.1
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• pp.35-42
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• 1996

A rapid analytical method based on capillary electrophoresis is described for the determination of trace anions in high-purity chemicals which is used to prevent corrosion demage in nuclear power plants. Separations are carried out at 20kV using trimethylsilane-coated fused-silica capillary ($70cm{\times}50$ or $75{\mu}m$ i.d.) with the electrolyte of 5mM Chromate(pH=8). Detection was achieved using on-column indirect photometry at 254nm. The simultaneous analysis of inorganic anions, chloride, nitrate, sulfate, azide and phosphate was performed using methods of hydrodynamic(>1ppm) and / or electrokinetic(<1ppm) injection. The results of studies on the coexisting anions on analyte ions shows that peak responses of analyte in hydrodynamic injection is constant without effect of coexisting anions, but those of analysis in electrokinetic injection is strongly dependant upon the kind of coexisting anions and its ionic mobility. The analyte enrichment rate, hence peak response, is positive relationship with the resistance of the sample solution. Thus, appropriate measures, such as standard addition or internal standard technique, must be used to account for differences in conductance of standard and sample solutions.