• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.05a
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• pp.113-116
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• 2005

In this paper, a computational and experimental analysis about the flow behavior of thin polymer film in the spin coating process for stable cover layer coating of a blu-ray disc is described. The blu-ray disc, a next-generation optical disc format over 25GB, consists of a 1.1mm thick substrate and a 0.1mm tick cover layer. Generally, cover layer on the blu-ray disc is made by the polymer spin coating process. However, it is hard to secure sufficient coating uniformity around the rim on the cover layer. In order to get the uniform thickness deviation and to minimize the bead around the rim, the edge of the disc substrate can be modified into various shapes around the rim on the disc and analyzed with various parameters, such as surface tension, viscosity, and rotation speed, etc. The optimal shape of the rim was tried to get by 3 dimensional computer simulation of the polymer expulsion process.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.3
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• pp.27-33
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• 2008

It is shown that the rate of wear can be related to 'index of wear intensity' using a leaf-spring in the disc on disk on wear tests. Since both upper and lower specimens have used the same hardness values, equivalent hardness of 'the index of wear intensity' used the mean hardness value of specimens. This index is derived from the external variables of load, sliding speed and the hardness of the sliding pairs. The wear behavior as the hardness of the sliding elements on the dry wear has been investigated using a disc on disc configuration. The materials of the specimens are used as ten kinds along their hardness. Using experimental data, we figured the relationship between wear rate and index of wear intensity. A newly wear equation had been derived the result using a leaf-spring in disc on disc wear system.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.5
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• pp.47-53
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• 2013

The wide application of disc springs to the designing of mechanical products with space limit is mainly attributable to their property of sustaining large axial load with small displacement. Due to the impediments in expecting the final results caused by the significant differences existing between a single unit and a stacked form, the force-displacement characteristics of a single disc spring and stacked disc springs are mainly examined in this study. In particular, the hysteresis of the series stack and the parallel stack will be investigated through the FE analysis and the analytical results will finally be compared with the acquired experimental data. In the final result, the analytical results were in accordance with the experimental data.

• Tribology and Lubricants
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• v.29 no.2
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• pp.85-90
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• 2013

The effects of contact pressure on the sliding wear behavior of mild steel in a pin-on-disc type apparatus were investigated. Sliding wear tests were conducted with various combinations of the load and apparent area of contact. The wear behavior of mild steel as a function of sliding speed was independent of contact pressure. However, the wear rate at different sliding speeds was influenced by the load regardless of the apparent area of contact. This was attributed to the fact that there may be no difference in the real area of contact for any combination of the load and apparent area of contact.

• Korean Journal of Occupational Health Nursing
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• v.21 no.2
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• pp.98-107
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• 2012

Purpose: In this research, we recognized the effects of DISC behavior styles of office workers on job satisfaction, organizational commitment and job performance, and tried to present a basic data for designing an efficient working system and enhancing the quality of personal life by applying them in the real office work environment. Methods: A survey was conducted for 315 office workers in D city from Jan. 28th to May 30th 2010, and the collected data were analyzed with the SPSS/WIN 17.0. Results: 1. The differences on job satisfaction, organizational commitment and job performance according to the general characteristics of subjects, were significant except for the gender in job satisfaction and education in organizational commitment. 2. Relationships in job satisfaction, organizational commitment and job performance of subjects, showed positive correlation. 3. Job satisfaction, organizational commitment and job performance according to the DISC behavior styles, were generally not significant. However, some questions were characterized by the DISC types. Conclusion: It is necessary to seek an efficient design method by identifying the differences of individual behavior types to enhance job satisfaction, organizational commitment and job performance of office workers, and such an effective job design should be made at the organizational level.

• Journal of Convergence for Information Technology
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• v.9 no.10
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• pp.254-263
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• 2019

This study was designed to understand the Education recognition, satisfaction, and job preferences of college students majoring in beauty through the DISC behavior type, and to be used as customized career and beauty education data considering individual tendencies through the DISC behaviour type. From September 20 to October 11, 2017, the final questionnaire was analyzed for students of beauty education who lived in South Chungnam Province and Gyeonggi Province. Significant differences in the Education recognition and job preferences of the study participants were shown, followed by D, I, S, and C, and were found to be satisfactory for their majors. Through this study, it is believed that it will be possible to identify the Education recognition, satisfaction and job preferences of college students in beauty education and use them as basic data that can help them decide their career path after beauty education.

• Tribology and Lubricants
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• v.35 no.2
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• pp.139-147
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• 2019

This study investigates the effects of corrosion resistance characteristics of opponent materials in relative motion on the sliding wear behavior of mild carbon steel. Pin specimens made of mild carbon steel are tested at several sliding speeds against mating discs made of two types of alloyed steels, such as type D2 tool steel (STD11) and type 420 stainless steel (STS420J2), with different corrosion resistance characteristics in a pin-on-disc type sliding wear test machine. The results clearly show that the sliding wear behavior of mild carbon steel is influenced by the corrosion resistance characteristics of the mating disc materials at low sliding speeds. However, the sliding wear behavior at high sliding speeds is irrelevant to the characteristics because of the rising temperature. During the steady state wear period, the sliding wear rate of mild carbon steel against the type 420 stainless steel at a sliding speed of 0.5 m/s increases considerably unlike against the type D2 tool steel. This may be because the better corrosion resistance characteristics achieve a worse tribochemical reactivity. However, during the running-in wear period at low sliding speeds, the wear behavior of mild carbon steel is influenced by the microstructure after heat treatment of the mating disc materials rather than by their corrosion resistance characteristics.

• Journal of Korean Association for Spatial Structures
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• v.23 no.4
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• pp.89-96
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• 2023

The seismic retrofits of existing structures have been focused on the control of structural responses which can be achieved by providing displacement capacity through inelastic ductile action at supplemental devices. Due to their hysteretic characteristics, it is expected to sustain damage through repeated inelastic behaviors including residual deformation which might increase repair costs. To solve such drawbacks of existing yielding devices, this study proposes a self-centering disc spring brace that sustains large axial deformation without structural damage while providing stable energy dissipation capacity. The hysteretic behaviors of suggested brace are first investigated based on the quasi-static cyclic test procedure. Experimental results present the effective self-centering behavior and an analytical model is then suggested in order to reasonably capture the flag-shaped hysteretic behavior of the disc spring brace.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.1155-1156
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• 2012

• Health Communication
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• v.13 no.2
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• pp.223-231
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• 2018

Background: Many nursing university students were stressed during clinical practice. The purpose of this study was to identify the difference between stress of clinical practice and mental health according to behavioral styles in nursing university students. Methods: The participants of this study were 233 junior and senior nursing students who had experienced clinical practice. Data were collected by self-report questionnaires in online from November 2017 to March 2018. Collected data were analyzed with SPSS/WIN 25.0 using descriptive statistics, t-test, ANOVA, Pearson correlation coefficients. Results: The most frequent DISC behavior style of the subjects was conscientiousness (43.8%), follewed by steadiness (19.7%), influence (18.9%), and dominance (17.6%). The participants'scores for stress of clinical practice and mental health were $3.35{\pm}0.55$ and $1.13{\pm}0.65$. The stress of clinical practice of the subjects was different according to DISC behavior styles(F=2.86, p=.038). The results show that the higher the score of stress of clinical practice was the higher the score of mental health(r=.51, p<.001). Conclusion: This study found that the difference of DISC behavioral styles can be attributed to stress of clinical practice. Therefore, nursing intervention program considering with the subjects'DISC behavior styles needs to be developed to reduce their stress of clinical practice.