• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.05a
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• pp.321-324
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• 2005

The main purpose of the present study has been placed on investigating the effects of controlled rolling and cooling on the microstructures and mechanical properties of C-Si-Mn-V steels for cold forming. The steels were manufactured in vacuum induction melting(VIM) furnace and casted to 1.1ton Ingots and the ingots were forged to $\Box150$ billet. The forged billets were reheated in walking beam furnace and rolled to coil, the stocks were rolled by Controlled Rolling and Cooling Technology (CRCT), so rolled at low temperature by water spraying applied in rolling stage and acceleratly cooled before coiling. Rolled coils were cold drawed to the degree of $27\%$ of area reduction without heat treatment. Microstructual observation, tensile test, compression test and charpy impact tests were conducted. The mechanical properties of the steels were changed by area reduction of cold drawing and it is founded that there are optimum level of cold drawing to minimize compression stress for these steels. From the result of this study, it is conformed that mechanical properties and microstructure of C-Si-Mn-V steels for cold forming were enhanced by accelerated cooling and founded optimum level of cold drawing.

• Journal of Korean Association for Spatial Structures
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• v.7 no.1 s.23
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• pp.71-78
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• 2007

Stainless steel is very famous for using of industrials structure and joint elements. Stainless steel wire drawing is one of the most ancient crafts. But there's not any standard size of tapered die during tile drawing. This paper was studied die angle and dimension of whole die by using AFDEX drawing simulator. Stress, metal flow and strain rate was analyzed by AFDEX tools during the wire drawing. So optimum data of during dies was taken from them. Simulation data was correspond with experimental data. The results of the optimum dies are shown that (1) Reduction angle is $13.8^{\circ}$ (2) Bark relief angle is $20^{\circ}$ (3) Bearing length is 0.7975mm (4) Bearing dia is 0.2393mm The research of the optimum result when the make dies is connected an enterprise. After researching, I hope that indirection effect creation make development situation of the manufactural technical, practical application of the other die size by the detail data, utility factor and economical efficiency.

• The Journal of Korean Academic Society of Nursing Education
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• v.12 no.2
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• pp.238-247
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• 2006

The purpose of this study is to investigate the relationship between nurslng students' self-differentiation, their stress level and stress coping strategies. And following research questions were established. First, what is the difference of the stress level depending on the self-differentiation? Second, what is the difference of stress coping strategies in accordance with the self-differentiation? Participants for this study were 159 students selected from the 1st grades of G University, located in Incheon Metropolitan city. SPSS 10.0 statistic program was taken for drawing its frequency, percentage, average and standard deviation. And t-test, F-test, correlation and multiple regression were conducted. The results are summarized as follows: 1. The mean score for the level of self- differentiation, level of stress, level of stress coping strategies were 3.59, 2.50, 3.35. 2. The relationship between self-differentiation and stress level revealed a negative significant correlation 3. The relationship between self-differentiation and stress coping strategies revealed a no significant correlation. 4. The relationship between stress level and stress coping strategies revealed a no significant correlation. Conclusion: The results of investigating the variation differences depending on stress level, self-differentiation, and stress coping strategies were revealed self-differentiation and stress coping strategies explained stress level by 28.6%.

• Proceedings of the KIEE Conference
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• 2006.07e
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• pp.23-24
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• 2006

Stator winding of hydro generator is gradually deteriorated by multi-stress and steady degradation of insulation results in insulation breakdown. The region where insulation breakdown occurs in stator winding is part where the multi-stress causes the defect of insulation material and electrical stress has been concentrated. Therefore, we judged locations of insulation breakdown to be varied according to various stress factors in service. In this paper, we drew the stator winding of hydro generators which has run for a long time and separated it into 3 parts(central part, end winding part, drawing part) according to the positions laid on the core. We performed electrical and thermal stress on these specimens for 1000 hrs under the same condition, measured the condition regularlyand analyzed the insulation status of each winding by performing partial discharge test. In addition, we analyzed the trend of partial discharge concerning specimens that caused the insulation breakdown during aging.

• Proceedings of the Korean Fiber Society Conference
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• 1987.06a
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• pp.14-14
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• 1987

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.509-510
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• 2008

• Journal of the Korean Society for Precision Engineering
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• v.25 no.12
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• pp.27-32
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• 2008

• East Asian Journal of Business Economics (EAJBE)
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• v.12 no.2
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• pp.43-50
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• 2024

Purpose: The present study investigates if the type of organizational culture influences the level of job-related stress. This study is significant because creating the need to explore the concept to become more informed on the best practices to promote and foster a positive culture that prioritizes workers, it could result in a healthier workforce, improved organizational performance, and success. Research design, data and methodology: Examining previous studies by other researchers was the primary research tool for this study. The organized approach of gathering data and assessing related work was vital in developing a fundamental basis for advancing knowledge on this concept while enhancing theory development and drawing more informed conclusion. Results: These four types, including the clan, adhocracy, hierarchical, and market cultures, contribute significantly in revealing four associations between the two variables, including (i) supportive culture and reduced stress, (ii) high pressure and increased stress, (iii)autonomous culture and variable stress levels, and (iv) open culture and low-stress levels. Conclusions: The literature affirms a multifaceted link between employee workplace stress and organizational culture type. The findings show that these cultures are crucial in influencing the level of stress among employees. All four types were hypothesized to have a significant relationship with job stress.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.6
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• pp.519-525
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• 2008

For this study, SM45C steel rods using generally for power transmission shafts and machine components was selected and welded by butt-GMAW method. And then it was studied about estimation of fatigue strength and the region of infinite life by Haigh diagram using Goodman's equation. Fatigue strength in weld zone presents highly in order of the boundary between deposited metal zone and heat affected zone, deposited metal zone, heat affected zone. This result agrees with distribution of hardness in weld zone. Fatigue strength in base metal zone presents highly compared with weld zone in low cycles between $10^4$ cycles and $10^6$cycles, but it presents the lowest fatigue strength on the order of heat affected zone in the vicinity of $10^6$cycles. It is the result that the first high compressive residual stress distributed by drawing process of the steel rods is released and the base metal is softened by alternating stresses. The region of infinite life by Haigh diagram presents highly in order of the boundary between deposited metal zone and heat affected zone, deposited metal zone, heat affected zone. From this results, it is demanded that the stress for safety design of machine components using SM45C butt-welded steel rods must be selected in the region of the lowest infinite life of heat affected zone.

• Korean Journal of Health Education and Promotion
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• v.29 no.3
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• pp.103-114
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• 2012

Objectives: The purpose of this study was to investigate the relationship between mental health status, stress, coping ability, and coping strategies of college students. Methods: The questionnaires were handed out to 162 college students in the Gyeonggi province. Data was collected using the Symptom Checklist-90-Revised (SCL-90-R) scale of the 90 items, the 'Person in the Rain' drawing test, and the 20-item coping strategies questions. Results: 17.3% of the respondents were belonged to the groups of abnormal or abnormal tendency in the mental health status according to the Global Severity Index (GSI) scores. The clinical/border groups were more commonly used in the 'emotion-focused' coping strategies compared to the normal group. This difference was also statistically significant. Both coping resource and coping ability were significantly associated with the mental health status. Conclusions: These findings suggest that future intervention for effective coping strategies should be carefully designed to promote better mental health among college students. It is also important to detect problematic and weak student's behaviors in the early stages.