• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.2
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• pp.265-281
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• 2017

For shallow tunnel constructions, settlement of the ground surface is a main issue. Recent technical developments in shield TBM tunneling technique have enabled a decrease in such settlements based on tunneling with ground deformation controls. For this objective, the tail void grouting is a common practice. Generally surface settlements in a soil of low permeability occur during a tunnel construction but also during a long period after completion of the tunnel. The long-term settlements occur mainly due to consolidation around the tunnel. The consolidation process is caused and determined by the tail void grouting which leads to an excess pore water pressure in the vicinity of the tunnel. Because of this, the grouting pressure has a strong effect on the long-term settlements in the shield tunneling. In order to investigate this effect, a series of coupled hydro-mechanical 3D finite element simulations have been performed. The results show that an increase in grouting pressure reduces the short-term settlements, but in many cases, it doesn't lead to a reduction of the final settlements after the completion of consolidation. Thereby, the existence of a critical grouting pressure is identified, at which the minimal settlements are expected.

• Korean Journal of Biological Psychiatry
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• v.1 no.1
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• pp.109-116
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• 1994

It is not known whether negative symptoms and cognitive functions are dissociable or improvements in symptoms are reflected in improvements in cognitive functions in chronic schizophrenic patients. We administered clozapine to evaluate its effect on cognitive functions in chronic schizophrenic patients and to show correlations between improvement in psychotic symptoms and in cognitive functions. Neuropsychological tests such as Wisconsin Card Sorting Test, Digit Span test and Judgment of Line Orientation Test were applied to 16 chronic schizophrenic patients at baseline and after 9 months of treatment with clozapine. Using BPRS we assessed psychopathology before initiation of clozapine and at 9 months. Clozapine improved both positive and negative symptoms in chronic schizophrenic patients significantly. After nine months of clozapine treatment, significant improvements occurred in attention, short-term memory and visual perception ability. And interestingly we noted the trend of improvement in executive functions even though they were not statistical significant. Any significant correlations between the clinical improvement and change in congnitive functions were not observed. Long-term treatment with clozapine improved parts of cognitive functions of chronic schizophrenics. The results of the study suggest that deficits in simple cognitive functions as well as psychotic symptoms are improved after 3 month period of short-term treatment, but executive functions requiring more sophisticated processing of information could be improved after more than 9 months of long-term treatment.

• Journal of the Korean Society of Safety
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• v.9 no.1
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• pp.146-154
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• 1994

A series of numerical calculations are performed in order to investigate the dispersion mechanism of toxic gaseous and solid pollutants in extremely short-term and short range. The calculations are carried out in an open space characterized by turbulent boundary layer. The simulation is made by the use of numerical model, in which a control-volume based finite difference method is used together with the SIMPLEC algorithm for the resolution of the pressure-velocity coupling problem. The Reynolds stresses are solved by two-equation, k-$\varepsilon$ model modified for buoyancy. The major parameters consider-ed in this study are temperature, velocity and Injection height of toxic gases, environmental conditions such as temperature and velocity of free stream air, and topographic factor. The results are presented and discussed in detail. The flow field is commonly characterized by the formation of a strong recirculation zone due to the upward motion of the hot toxic gas and ground shear stress. The driving force of the upward motion is explained by the effect of thermal buoyancy of hot gas and the difference of inlet velocity between toxic gas and free stream.

• Journal of Korean Society for Quality Management
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• v.31 no.4
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• pp.19-35
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• 2003

With the increase in family income in Korea and the improving quality of life, there is a rapid growth in the restaurant industry. Therefore there is a demand for quality service in this industry. This paper reviews the relationship between service quality and the degree of employee empowerment. The first objective of this research is to test the effects of employee empowerment on service quality, and the second one is to test how tenure affects this relationship. According to statistical analysis, meaning, competency, and autonomy generally have an affirmative impact on many service quality factors. Also the results of regression analysis to test the moderation effect show that long term employees are more sensitive to autonomy than short term employees.

• Proceedings of the Safety Management and Science Conference
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• 2006.04a
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• pp.471-484
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• 2006

The focus of analysis is effect on Non-electrical Machinery and Equipment of Macroeconomic variables through long-term and short-term periods. Also, this paper is related with implication on steady growth possibility of Non-electrical Machinery and Equipment. The period of variables is from 1985 to April in 2005. In case of not-available data is treated as missing figures. As spatial scope, these data are Non-electrical Machinery and Equipment on the basis of KSIC. In case of items, it composes MTI 1&3 digit of Korea International Trade Association (KITA), on the basis of HSK & classification of Korea Machinery industries. According to Granger causality test, yield of Cooperate Bond and export amount of Machinery have a meaning at statistical Confidence level of 10%. In case of index of the unit cost of export and export amount of Machinery, they have an interactive Granger cause. In yen dollar exchange rate and export amount of Machinery, former variable gives an unilateral Granger cause to latter that.

• Journal of Korean Society for Atmospheric Environment
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• v.2 no.3
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• pp.19-26
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• 1986

The degree of air pollution is usually presented in terms of concentration. But, in evaluating the environmental impacts or air pollution control policies, the concentration values need to be interpreted in terms of damage effects on property and human health. The damage effect varies with the types of pollution, subjects and land use pattern of an affected area. Therefore, this study is aimed at developing a method of analyzing effects of various types of air pollutions on surrounding environmental setting with the EIMS (Environmental Information Management System) developed for land suitability analysis. Using the method formulated in this study, the long- term effects of such pollutants as $SO_2$ and HF on types of vegetation and residents, and potential, short-term effects of HCl leak accidents from manufacturing facilities in Ulsan and Onsan Industrial complex are analyzed. The presentation of the damage effects of air pollution rather than the concentration of pollutants will be useful for the preparation of environmental impact statements, the formulation of environmental policies, and the development of land use plans in heavily industrialized areas.

• Journal of radiological science and technology
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• v.8 no.2
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• pp.65-69
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• 1985

In order to investigate the effects of sulfamonomethoxine (SMM) on thyroid glands in short term administration as medical dose, a total of twenty albino rabbits (mean body weight 1,750g) were selected at random and allotted to control and experimental group. Rabbits in experiment were administered SMM of 50 mg/kg/day for 30 days, and histopathological changes of thyroid glands and the blood levels for T4 and T3 were observed every 5 days. The Results obtained were summarized as follows: 1. The thyroid follicles were decreased or obliterated by highly hypertrophic and hyperplastic epithelial cells and the newly formed small follicles contained scanty colloidal materials. These changes revealed increasing tendency in accordance with the experimental days. 2. The blood levels for T4 and T3 of experimental group manifested significantly decreased values than those of control through the experimental term consistently. Finally, above observations suggest that administration of SMM to animals leads thyroid glands to typical hypofunctional hyperplastic goiter.

• Journal of Distribution Science
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• v.13 no.4
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• pp.29-33
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• 2015

Purpose - This paper aims to explain the interactive relationship between small and medium-sized enterprises' clusters and regional economic growth, with Jiangsu Province as an illustrative example. It focuses on studying the promotional effects, if any, of small and medium-sized enterprises' cluster-development on regional economic growth, and vice-versa. Research design, data, and methodology - Data were collected from the Jiangsu Statistical Yearbook and the China Industrial Economic Statistical Yearbook, by selecting 26 industries as the research subjects. The sample interval selection is 1981-2012. The data were analyzed with the dynamic panel system using stata 12.0. Results - 1) The small and medium-sized enterprises' cluster degree and Jiangsu's economic growth have a long-term stable equilibrium relationship. 2) In the short term, they have a dynamic adjustment 3) The enterprises' cluster degree leads to regional economic growth in Jiangsu, but not vice-versa. Conclusions - Small and medium-sized enterprises' clusters have an important promotional effect on Jiangsu's economic growth, especially industries with high degree of agglomeration. Therefore, the formation of these clusters can significantly improve economic growth.

• Korean Journal of Health Education and Promotion
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• v.20 no.4
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• pp.111-127
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• 2003

The government of Korea enacted the National Health Promotion Act in 1995, and set aside funds for national health promotion, endeavoring to reduce the smoking rate of its citizens. Consequently, smoking rates in all age groups of both sexes were lowered during the period of 1999-2003 when legal backing and financial support for no-smoking policies from the national health promotion funds were provided. The decrease in the smoking rate is attributed to the combined effort of the fact that enactment of related acts, their implementation, financial support, and education and publicity 'campaigns on no smoking. However, at the current pace of decreasing the smoking rates, it will be difficult to achieve the Health and Welfare Ministry's smoking rate goal of30％ among adult males by 2013. Thus, related acts should be reshaped, corresponding support should be increased, and financial support should also be provided to implement comprehensive no-smoking policies. Also, budgets should also be alloted to establish a system of providing feedback on the monitoring and evaluation of both short-term and long-term no-smoking business planning and implementation.

• The Korean Journal of Gastroenterology
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• v.72 no.5
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• pp.245-251
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• 2018

Gastric cancer is the most common cancer in Korea and the fifth most common cancer globally. Helicobacter pylori (H. pylori) infection is considered the main etiologic agent for gastric cancer development. Most regional guidelines for H. pylori treatment recommend treating the organism to prevent gastric cancer in the high-risk group. However, evidence that such a strategy can also be applied to the general population, especially in terms of the preventive effect and safety, has not been adequately presented yet. Although a meta-analysis in the general population suggested effectiveness in decreasing gastric cancer incidence, individual studies should be critically reviewed to evaluate the soundness of the evidence. Recently published, long-term, Korean studies on metachronous gastric cancer prevention ended the controversies from previous short-term studies and confirmed the effectiveness. Currently, further prospective, large, randomized studies are ongoing in the general population and will provide more definitive, high-level evidence on this gastric cancer prevention strategy in the next decade.