• Journal of Korean Society of Environmental Engineers
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• v.30 no.7
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• pp.705-711
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• 2008

In case of the domestic condition, as the initiating from Sumjin River Dam, total 14 units of multipurpose dams had been constructed in 1965 for the roles of flood control, waterpower generation, irrigation, water supply, industrial water supply. In the case of such multipurpose dam, it produces electric energy by converting the potential energy utilizing its head and quantity of the water into kinetic energy. However, in this process, since during the time when the turbine connected to the hydraulic turbine dynamo revolves and there occurs a loud noise, it brings the physical, mental bad influences to those people also a decline of an effective working efficiency. On such point of view, after selection of various 16 measurement points, this study has measured and analyzed the travelling characteristics of noise generated at the hydraulic turbine dynamo in Daechung Dam, and also has evaluated the degree of indoor noise using the evaluation index such as PSIL, NC. As the result of noise-evaluation, in case of Daechung Dam, since the noise damage grade appears very seriously at various spaces, it is considering that its soundproof measure would be necessitated keenly. Also, it is considered that such data could be utilized as the valuable material hereafter for establishment of an efficient noise-reduction countermeasure and a comfortable working environment for the hydraulic turbine dynamo plant.

• Journal of Acupuncture Research
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• v.32 no.2
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• pp.217-227
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• 2015

Objectives : This study is an evaluation of the effectiveness of treatments combined with Korean medical methods, such as relaxative Chuna and Gangchuk herbal medicines, for patients with failed back surgery syndrome. Methods : In this study, medical records of ten patients who experienced failed back surgery syndrome and participated in intensive Korean medical treatment were reviewed. All patients received relaxative Chuna and acupuncture along with Gangchuk herbal medicines during hospitalization. Numeric rating scale(NRS) in the degree of 0 to 10, pain-free walking distance(PFWD) and oswestry disability index(ODI) were measured before and after treatments. Results : The patients were hospitalized for an average of 22 days. The average NRS of lumbar pain in all patients decreased from $7.7{\pm}1.6$ to $3.2{\pm}2.2$ and the average NRS decline of leg pain was from $7.7{\pm}1.7$ to $3.2{\pm}2.2$, both of which indicate statistical significance(p < 0.05). PFWD in all patients increased from 113.3 m to 798.1 m on average. The average ODI in all patients significantly improved from $63.9{\pm}7.0$ to $43.9{\pm}6.9$(p < 0.05). Conclusions : The treatments combined with Korean medical methods for failed back surgery syndrome patients are clinically effective and viable.

• Journal of the Semiconductor & Display Technology
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• v.13 no.4
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• pp.21-25
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• 2014

The silicon nitride ($SiN_x$) film for surface passivation and anti-reflection coating of crystalline silicon solar cell is very important and it is generally deposited by plasma enhanced chemical vapor deposition (PECVD). PECVD can be divided into low and high frequency method. In this paper, the $SiN_x$ film deposited by low and high frequency PECVD method was studied. First, to optimize the $SiN_x$ film deposited by low frequency PECVD method, the refractive index was measured by varying the process conditions like $SiH_4$, $NH_3$, $N_2$ gas rate, and RF power. When $SiH_4$ gas rate was increased and $NH_3$ gas rate was decreased, the refractive index was increased. The refractive index was also increased with RF power decline. Second, to compare the characteristics of the low and high frequency PECVD $SiN_x$ film, the refractive index was measured by varying $NH_3/SiH_4$ gas ratio and RF power and the minority carrier lifetime of before and after high temperature treatment process was also measured. The refractive index of both low and high frequency PECVD $SiN_x$ film was decreased with increase in $NH_3/SiH_4$ gas ratio and RF power. After high temperature treatment process, the minority carrier lifetime of both low and high frequency PECVD $SiN_x$ film was increased and increased degree was similar. The minority carrier lifetime of low frequency PECVD $SiN_x$ was increased from $11.03{\mu}m$ to $28.24{\mu}m$ and that of high frequency PECVD $SiN_x$ was increased from $11.60{\mu}m$ to $27.10{\mu}m$.

• Review of Culture and Economy
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• v.21 no.2
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• pp.175-196
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• 2018

When social disaster which is a phenomenon that causes a big wave to the social members occurs, the members of the society are anxious and show feelings of shame or guilt over behaviors that are against social norms. This sense of guilt is expected to reduce consumption of arts having its luxury and hedonic characteristics. The purpose of this study is to identify the causes of the decline in art consumption at the time of social disasters and we focus on guilt. We hypothesize that guilt for art consumption at the time of social disasters will increase as the tendency toward guilt is higher and the empathy tendency is higher. A result of the questionnaire survey of 286 people shows that the higher the guilt for art consumption in the social disaster situation, the more the art consumption decreased and the guilt changed depending on the degree of personal guilt and sympathy. This study contributes to explaining the decrease of art consumption in a big social phenomenon in recent years.

• Journal of Korean Society of Forest Science
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• v.113 no.3
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• pp.292-307
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• 2024

This study aimed to develop an index to assess the level of revitalization in mountain villages by utilizing big data and to verify its applicability in such areas. To achieve this, four key indices related to mountain villages were developed to evaluate the degree of revitalization, namely, Settlement Index, Workplace Index, Learning Index, and Leisure Index. These indices enable users to compare the revitalization levels of different mountain villages by establishing living zones, assigning data weights, extracting comparative data, and generating results in both map and report formats. The revitalization index developed in this study was applied to five mountain villages (A, B, C, D, E) located in Jeollabuk-do. Results showed that Village C had the highest comprehensive score of 320 points, while Village E had the lowest score of 141 points. In the mountain village indices of Jeollabuk-do, the Workplace Index generally showed higher scores, whereas the Learning Index had relatively lower scores on average. The development of these indices provides a practical means to identify which areas should be prioritized for support to enhance revitalization in specific mountain villages and offers a clear comparison of the revitalization levels across different regions and individual villages. The mountain village revitalization index developed in this study is expected to serve as valuable foundational information for formulating mountain village revitalization policies.

• Food Science and Preservation
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• v.11 no.2
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• pp.170-174
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• 2004

Whole muskmelon was blanched at 50$^{\circ}C$ water for inhibition decline of fresh-cut melon quality from direct heat treatment. The muskmelon, after storage at 5$^{\circ}C$ for 24 hours, was processed to melon cylinders with 2 cm diameter. The changes of color, texture and the quality characteristics such as gas composition. soluble solid content, pH during storage at 5$^{\circ}C$ were measured. Degree of oxygen contents decreased and that of carbon dioxide in melon cylinder increased during storage. Especially, changes of gas composition inside packages appeared high level cor in blanched melon cylinders than non-treatment melons. Blanching with whole fruits at 50$^{\circ}C$ had effects on hardness in melon cylinder. Blanched melon, without regard on branching time, appeared higher hardness value than that of non-blanched melon at 6 days storage. There were slight difference between treatment on melon cylinder color. Degrees of change in soluble solid contents and pH on melon cylinder blanched at 50$^{\circ}C$ for 20minuets were lower than that of other treatments. In consequence, blanching with whole fruit at 50$^{\circ}C$ for 20minuets, before minimal processing, was effective in preserving of texture and quality of melon cylinder during storage.

• 대한공업교육학회지
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• v.45 no.1
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• pp.84-102
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• 2020

During the period of rapid industrial growth, specialized high schools were important vocational education institutions trained specialists and technicians. But now, specialized high schools turned into high schools where the low-ranking students who were pushed out of the competition for admission due to a decline in the education population, changes mostly in labor demand in the labor market, and discrimination against skilled workers. In order to solve this problem, the middle school 3rd grade teachers in charge of the middle school can provide early career guidance, so that they can decide to go to the specialized high school according to their aptitude and talent rather than their grades. The purpose of this study is to investigate the relationship between general characteristics and perception of middle school 3rd grade teachers, and the rate of decision to enter specialized high school. In 2018, The middle school 3rd grade teachers in charge in Daejeon metropolitan city were selected. The results of this study were as follows: When 3rd grade teachers in charge are the male teachers 21.01%(M=.2101) of their students go to specialized high schools. When they are teachers who have not graduated from college of education(M=.2110), with doctoral degree(M=0.3064), of their students go to specialized hight schools. Finally, there was a significant positive relationship between perceptions of high school teachers (β1 = .245, p = .000) and high school graduates (β2 = .149, p = .027). The regression equation derived from this is y = -0.56 + 0.037 * β1 + 0.025 * β2 10.1% (R² = 0.101).

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1296-1302
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• 2013

The quality of fresh jujube (Zizyphus jujuba) fruit rapidly declines in the postharvest stage and thus the effective storage conditions for agricultural warehouses were investigated in this study. Fresh jujubes (~10 kg) were stored using five different storage methods: plastic box without further packaging as a control (C-PL), plastic box with hanji packaging (H-PL), plastic box with functional film packaging (F-PL), cardboard box with hanji packaging (H-CB), and cardboard box with functional film packaging (F-CB). The storage boxes were stored in a refrigerator ($0^{\circ}C$ and 80~90% RH), equipped with an ethylene gas scavenging device for 9 weeks and then the quality characteristics were analyzed. The control storage conditions of jujubes showed a substantial decline in quality with decreases in moisture content, hardness, and sugar content as well as increases in decay ratio and redness. Among the tested storage conditions, F-CB was most effective in terms of maintaining the quality of jujube fruit while maintaining firmness, weightlessness, ripening degree from redness and visible appearance. In conclusion, effective storage and packaging conditions during storage enabled maintenance of fruit quality of jujubes for 9 weeks.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.163-169
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• 2019

This study examined whether industry-level competition affects excess stock returns because of changes in cash holdings. Competitive inter-company threats increase the possibility of the manager's replacement, and function to induce management to make their best efforts, resulting in the amount and quality of the information provided by the enterprise increasing. Therefore, as competition intensifies, agency problems are reduced and stock returns increase because the company's cash holdings are expected to increase. However, there is a view that firms in industries with severe competition tend to have high information asymmetry because competitors may compete in more favorable positions by using detailed information disclosed by the competing firms. Accordingly, as market competition intensifies, the excess stock returns resulting from increased cash holdings are expected to decline. These results show that excess stock returns because of increases in cash holdings increase as the degree of competition in the industry intensifies, thus supporting the positive effect of market competition. Overall, the results of this study provide an understanding that market competition plays an effective external governance mechanism and that investors positively evaluate the cash held by companies with severe industry competition.

• Environmental and Resource Economics Review
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• v.18 no.4
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• pp.587-635
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• 2009

The purpose of this study is to develop the Global Dynamic Computable General Equilibrium Model (Global CGE Model) in order to produce an economic impact analysis, including prospective obligations for the Post-2012 regime. This model explores the impact of an international emissions trading market and macroeconomic variables such as GNP, consumption, investment, imports and exports, in accordance with potential increased obligations on the Republic of Korea. Distinguishing it from existing studies, this Global CGE Model divides the global community into major economic groups, and in the capacity of the analyzed global model, reflecting the principle nations' macroeconomic indicators through the theoretical approach of endogenous growth theory. Policies such as an emissions trading scheme and carbon tax are reflected in the model. Also, in particular, the model reflects exogenous technological advances. According to this analysis, the stronger the greenhouse gas reductions, the greater the adverse effects on the economy; among macroeconomic indicators that appear, a significant decline is realized in the balance of trade, along with a significant decrease in investment and consumption. Energy dependence, in particular, plays a large role-varying in degree by industry type-, as greenhouse gas reductions would have a greater impact on energy-intensive industries. Furthermore, if Korea, currently recognized as a developing country, is given the obligation to reduce greenhouse gas emissions, competing countries such as China and other developing countries will be given an advantage.