• 한국진공학회지
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• 제7권s1호
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• pp.149-155
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• 1998

The linear electro-optic (EO) effect is one of the second-order nonlinear optical effects existing in a noncentrosymmetric macroscopic system. In a polymer thin film, the noncentrosymmetry is achieved by electric field poling. The magnitude of the linear EO response is determined through the orientational distribution function of hyperpolarizable molecular dipoles. The relation between the linear EO coefficient and the second-order nonlinear optical susceptibility is explained. Three different methods of measuring the linear EO coefficient of a poled nonliner optical polymer thin film are introduced and discussed. All of them make use of the interferometric technique, the difference being in the optical parameters which are interfering.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1988년도 학술발표초록집
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• pp.34-34
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• 1988

The pyroelectricity of poly(vinylidenefluoride) films prepared by varying the draw ratio and the poling field was investigated. As the draw ratio and the electric field on poling of the drawn samples increased, so did the pyroelectric coefficient. But the effect of electric field on the pyroelectricity was greater than that of draw ratio. The pyroelectric and piezoelectric activities could be explained by the polarization using the thermally stimulated current. The relation between pyroelectric coefficient and piezoelectric stress constant showed a good linearity.

• 한국산학기술학회논문지
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• 제6권1호
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• pp.72-77
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• 2005

본 연구에서는 점토퇴적지반의 투수특성을 실험적으로 연구하기 위하여 표준압밀시험, 일정변형률압밀시험 등을 수행하였다. 시험결과를 분석하여 비등방성, 투수변화지수, 간극비와의 관계 및 투수계수에 영향을 미치는 다양한 영향요소에 관하여 고찰하였으며, 대표투수계수를 제안하였다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제5권3호
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• pp.325-332
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• 2013

Diffuse interface model for numerical analysis was used to compute supercavitating flows around various cavitators. The ambient pressures of 2 atm permitted cavitation studies in a range of cavitation number, ${\sigma}=0.1$ to 1.0 on selected conical and disk-headed cavitors. The computed results were compared with relation by Reichardt. Drag coefficient obtained from pressure forces acting on the cavitator also compared well with those obtained from analytical relations.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1617-1619
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• 2000

In this study the nonlinear dielectric properties of amorphous copolymers were analyzed by the related nonlinear dielectric theory. The theory is related to the cooperated dipoles and the number of the dipoles. The relation between the polarization coefficient $R_p$ and the nonlinear coefficient $R_s$ was deduced under the assumption of isotropic media.

• 한국환경과학회지
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• 제17권4호
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• pp.451-459
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• 2008

This study was carried out forecasting of pollution inflow of the Small Mountainous Catchment, namely; Seolma-cheon experimental catchment. Pollutographs of DO, BOD, T-N, Conductivity, T-p, pH. COD, SS from this catchment were obtained from in-situ data of total ten events using QUAL2E-PULS model. From the analysis results, between up stream(Sabang-bridge) and down stream (Memorial-bridge, outlet) obtained relation formula of water quality component. Determination coefficient of relation formula, Conductivity, COD, BOD, DO, pH, T-N, T-P, and SS showed high relation of $0.87{\sim}0.99$. The increases of DO, BOD, COD, and pH concentration of Memorial-bridge were associated with pollution inflow by road building far 2.25km from Sabang-bridge to down stream. The analysis results of QUAL2E-PULS simulation and up/down stream relation formula, pollution amounts of DO, BOD, COD and pH increased at Memorial-bridge and pollution source site. Therefore, pollution inflow can be forecasted exactly by up/down stream relation formula at pollution source site.

• 한국세라믹학회지
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• 제34권8호
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• pp.797-802
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• 1997

The use of carbon materials in mechanical components such as bearings, seals, and bushings that do not require lubricants is increasing rapidly. This paper reports on establishing the optimal condition for resin-bonded carbon materials. We fixed the content ratio of materials, which include graphite powder and diatomite as a lubricant modifier and a friction modifier, respectably, with resin used as a bonding material. We then produced bushings using hot-pressing within the temperature range of resin curing. The properties of bushing, the friction coefficient, wear rate and the mechanical strengths are discussed in relation to the content of respective materials, with correlation of friction coefficient and sliding distance. Finally, we examined the friction coefficient changes according to the applied load on bushing and the friction coefficient changes according to contact speed of bushing.

• 한국IT서비스학회지
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• 제13권3호
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• pp.165-181
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• 2014

This study proposes the accurate labor inducement coefficient (employment inducement coefficient/hiring inducement coefficient) of Korea software industry by analyzing the inter-industry relation using the modified inter-industry table. To rewrite the inter-industry table of Korea, some previous studies related to the inter-industry analysis were reviewed and the key problems were identified. First, in the current inter-industry table published by the Bank of Korea, the output of software industry includes not only the pure software related output but also the output of non-software section due to the misclassification of the industry. This causes the output to become bigger than the actual output of software industry. Therefore, if the inter-industry table is not modified, the labor inducement coefficient would be overestimated too much. Second, during rewriting the inter-industry table, the output is changing. The inter-industry table is the table in the form of rows and columns, which records the transactions of goods and services among industries which are required to continue the activities of each industry. Accordingly, if only an output of a specific industry is changed, the reliability of the table would be degraded because the table is prepared based on the relations with other industries. This possibly causes the labor inducement coefficient to be over or underestimated. This study tries to correct these problems to get the more accurate labor inducement coefficient of the software industry. First, to get the output of the pure software section only, the data from the Korea Electronics Association (KEA) was used in the inter-industry table. Second, to prevent the difference in the outputs during rewriting the inter-industry table, the difference between the output in the current inter-industry table and the output from KEA data was identified and then it was defined as the non-software section output for the analysis. The followings are the labor inducement coefficient obtained when the output is divided into the pure software section (package software, and IT service) and non-software section. As of 2011, the employment inducement coefficients of pure software section, package software section and IT service of Korea were 8.616, 13.998, and 7.773 respectively while the labor inducement coefficients of pure software section, package software section and IT service of Korea were 7.979, 13.332, and 7.083, respectively.

• 한국간호교육학회지
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• 제26권3호
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• pp.290-298
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• 2020

Purpose: This study aimed to grasp the correlation between communication ability, empathy, and interpersonal relations among nursing students, and to explore the mediating effect of empathy on the relation between communication and interpersonal relation in nursing students. Methods: Participants were 209 college students in the Department of Nursing at two universities. The data collection period was from October 1, 2019 to November 1, 2019. The questionnaire consisted of measuring tools for general characteristics, communication ability, interpersonal relation and empathy. SPSS/23.0 program was used. The analysis used descriptive statistics, Pearson's correlation coefficient, independent t-test, one-way ANOVA, multiple regression analysis, and Sobel's tests. Results: The communication ability was nursing major satisfaction (t=8.25, p<.001), and last year's average grade (t=7.29, p=.001). Interpersonal relationships showed significant differences in gender (t=2.51, p=.013) and nursing major satisfaction (t=10.99, p<.001). Communication ability and empathy (r=.37, p<.001), communication ability and interpersonal relation (r=.77, p<.001), empathy and interpersonal relation (r=.43, p<.001) showed a significant static correlation. In communication ability and interpersonal relation, empathy had a partial mediating effect (Z=2.97, p<.001), and explanatory power was 62%. Conclusion: To improve the communication ability and interpersonal relation of nursing students, it is necessary to develop a personalized and empathy-enhanced education program for each grade.

• 한국수자원학회논문집
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• 제37권12호
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• pp.1055-1063
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• 2004

공간적 위치 및 유량 값에 따라 각 계산점마다 조도계수의 값이 달리 주어질 수 있도록 하는 가변 조도변수 부정류 계산모형을 수립하였다. 유량과 조도계수의 관계식으로는 계단함수 또는 멱함수를 적용할 수 있도록 하였다. 수립된 모형을 충주댐부터 팔당댐까지의 남한강 구간에 적용하여 최적화에 의한 매개변수의 추정을 수행하였다. 가변 매개변수 모형의 보정 결과, 계단함수 도형 및 멱함수 모형 모두 유량이 커질수록 조도계수가 감소하는 경향이 일관되게 나타났다. 이러한 경향은 여주 지점 상류구간의 경우에 더욱 현저한 것으로 나타났다. 가변 조도계수 모형의 매개변수 추정에 따른 오차가 고정 조도계수 모형의 경우보다 작아짐을 알 수 있었다.