• 설비공학논문집
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• 제14권9호
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• pp.725-733
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• 2002

In this study, the heat transport limitations of a two-phase closed thermosyphon were investigated. For the test, a two-phase closed thermosyphon ($L_t/: 600 mm,\;L_e:105mm,\;L_a:75mm,\;L_c:420mm,\;D_o:22.2mm,$ container: copper (inner grooved surface), working fluid: PFC ($C_6F_14$) was fabricated with a reservoir that can change the fill charge ratio. The following was imposed as the factors on the heat transport limitations of a two-phase closed thermosyphon. 1) Fill charge ratio of the working fluid. 2) Tilt angle of the longitudinal axis. From tile experimental data, some results were obtained as follows. When the fill charge ratio was relatively small ($\psi$20%), the heat transport limitation occurred about 100W by dry-out limitation. However over 40%, it shelved nearly constant value (500 W) by flooding limitation. The heat transport limitation according to the tilt angle increased smoothly until the tilt angle was $60^{\circ}$,/TEX>, after then decreased slowly.

• 대한조선학회논문집
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• 제48권1호
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• pp.33-41
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• 2011

For the assessment of ultimate longitudinal strengths of damaged hull girders, it is preliminarily necessary to determine the extents and locations of the damages due to severe accidents. This paper deals with the estimation of the damages from collisions and groundings of large-sized vessels where deterministic and probabilistic approaches are investigated. Deterministic damages estimated from MARPOL(or ICLL), ABS and DNV are compared with probabilistic damages from IMO guideline and some references including damage statistic data. Damages from MARPOL show largest one among all the investigated damage estimation, since it was developed not for the residual strength of hull girder but for the damage stability calculation. IMO guideline with high level probability of damage(eg. 95% probability level) also forecasts even severer damage extents than MARPOL. On the other hand, assuming average probability level of damage, the calculated damage sizes are around the one from deterministic approaches.

• 한국수자원학회논문집
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• 제35권2호
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• pp.195-201
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• 2002

본 연구에서는 자연하천의 만곡수로에서 종방향 유속으로 인해 현재보다 더 이상 횡 방향 경사의 변형이 일어나지 않아 세굴이 감소하고 하상이 횡방향으로 안정한 상태를 유지할 수 있는 적정 유속의 한계인 한계속도를 제시하였다. 한계속도의 이론 유도는 하상횡경모형의이론적 배경이 되는 운동량모멘트방정식으로부터 얻은 하상면 횡방향전단력성분과 이에 대응하는 하상전단력과의 힘의 평형으로부터 유도되었다. 이론식의 검증을 위해 4개 자연하천수로의 실측자료론 적용하여 계산치와 실측치를 비교한 결과 잘 일치하였다. 적용결과에서 보정계수와 만곡수로의 평균입자 Froude수는 밀접한 상관관계를 갖고 있는 것으로 나타났다.

• 보건교육건강증진학회지
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• 제32권1호
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• pp.45-55
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• 2015

Objectives: This study is aimed at exploring the temporal developmental relationship of adolescent depression and parents' child-rearing attitudes, and to examine gender differences in the relationship. The middle school students of the 2011-2013 1st Korea Children and Youth Panel data were used for analysis and the sample consisted of 2.073 individuals. Methods: Research questions were answered through the Latent Growth Model and Autoregressive Cross-Lagged Model. Results: As the results of the Latent Growth Model show, adolescent depression declines as time goes by and there are differences in the depression felt by individuals. An autoregressive cross-lagged model and multiple group analysis were executed by gender. The results show significant gender differences in the relationship between depression and Parents' child-rearing attitudes. Parental neglect has shown differences influencing adolescents depression between males and females. However, in case of parental abuse, no differences between males and females were observed. Conclusion: The results of this study imply that the policy on depression should be carefully considered when preparing for interventions targeting adolescents by gender.

• 지역사회간호학회지
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• 제16권1호
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• pp.32-39
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• 2005

Purpose: this study was to verify the effects of the smoking prevention education as an intervention to prevent smoking among male middle school students. Method: this study was designed using one group pre-post test. The subjects were 169 male middle school students living in Jecheon city. The instruments used in this study were scales on smoking cessation intention and knowledge and attitude toward smoking. Students received 8 sessions of smoking prevention education for 45 minutes every week. from April to July 2003. The data was analyzed by descriptive statistics and paired t-test using the SPSS Win 8.0 program. Results: after the completion of the smoking prevention education, the smoking cessation intention(t=.37, p=.705)was not increased significantly but the knowledge(t=-3.84. p=.000) and attitude(t=-3.16, p=.002) on smoking were increased significantly. Conclusion: the smoking prevention education for male middle school students increased their knowledge on smoking and student's attitude to smoking turned more negatively. Further study on longitudinal effect using Pre-test/ Post-test control group design are also recommended.

• 대한족부족관절학회지
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• 제17권4호
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• pp.309-315
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• 2013

Purpose: The purpose of the study was to investigate five cases with chronic Achilles tendon rupture that occurred after steroid injections. Materials and Methods: In our hospital, we experienced five cases of chronic Achilles tendon rupture from September 2010 to March 2012. All patients had got steroid injection for Achilles tendinitis at the other hospitals, and their heel pain was aggravated when they visited our outpatient department. After treatment, signs and symptoms of Achilles tendon rupture were developed and the diagnosis was confirmed by ultrasonography or magnetic resonance imaging (MRI). Surgical treatment was done for Achilles tendon rupture. Results: There was difference between intra-operative findings of Achilles tendon rupture and usual chronic Achilles tendon rupture. Unlike usual findings of chronic Achilles tendon rupture whose scar tissue or tissue attenuation are found around the defect area of Achilles tendon, there were partial necrosis of tendon severe adhesion with surrounding tissue, extensive defect and longitudinal rupture on ruptured area. Also, severe inflammation of paratenon, granulation and fibrinoid deposit were found on biopsy findings in four cases. Conclusion: Based on review of data about relative risk and benefit of local corticosteroid injection to inflammatory lesion in Achilles tendon, it requires more attention to Achilles tendon rupture following local corticosteroid injection.

• 가족자원경영과 정책
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• 제15권4호
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• pp.65-78
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• 2011

The purpose of this study was to examine the experience of retirement and how life satisfaction after retirement differs depending on the individual, family, and social characteristics of middle-aged and elderly Korean men and the experience of retirement. Data were drawn from the first wave of the Korean Longitudinal Study of Ageing (KLoSA). The sample consisted of 278 retired middle-aged and elderly Korean men aged between 45 and 64. The results showed that middle-aged and elderly Korean retirees' reasons for retirement differed depending on their health satisfaction. In addition, their retirement satisfaction varied according to their education, health satisfaction, economic satisfaction, and reasons for retirement. Regarding their life satisfaction, it was predicted by their age and satisfaction with health status, economic situation, marriage, and relationship with their children.

• 대한가정학회지
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• 제34권3호
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• pp.75-87
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• 1996

The purpose of the study was to examine the effect of sex role orientation on the amount of time spent in meal preparation and cleanup, clothing care, and indoor cleaning accomplished by husbands and wives in couple-headed households in the U.S.. The overall research hypotheses examined were : (1) there is a relationship between demographic and socioeconomic characteristics of the husband and wife and the sex role orientation of the husband and wife; (2) for both husbands and wives, there is a relationship between sex role orientation and the amount of household production time that is accomplised by each individual; and (3) the relationship between sex role orientation and the amount of household production time remains when demographic and socioeconomic factors are controlled. The 1981 data from the 1975-1981 Time Use Longitudinal Panel Study collected at the University of Michigan were used for this study. The major findings is that a relationship between sex role orientation and the amount of time spent in three household production activities was not found, when all independent variables were controlled. That is, sex activities was not found, when all independent variables were controlled. That is, sex role orientation was not a predictor affecting the amount of time that husbands and wives spend on meal preparation and cleanup, clothing care, and indoor cleaning.

• E2M - 전기 전자와 첨단 소재
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• 제8권6호
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• pp.685-692
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• 1995

The electron transport coefficients in argon gas is studied over the range of E/N values from 85 to 566 Td by the Monte Carlo method considering the latest cross section data. The result of the Monte Carlo method analysis shows that the value of the electron transport coefficients such as the electron drift velocity, the ratio of the longitudinal and transverse diffusion coefficients to the mobility. It is also found that the electron transport coefficients calculated by the two-term approximation analysis agree well with those by Monte Carlo calculation. The electron energy distributions function were analysed in argon at E/N=283, and 566 Td for a case of the equilibrium region in the mean electron energy. A momentum transfer cross section for the argon atom which was consistent with both of the present electron transport coefficients was derived over the range of mean electron energy from 10.3 to 14.5 eV, also suggested as a set of electron cross section for argon atom. The validity of the results obtained has been confirmed by a Monte Carlo simulation method.

• 한국전기전자재료학회논문지
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• 제29권1호
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• pp.62-67
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• 2016

In this paper, the IES file was measured by applying a secondary optical lens to a 21 W LED engine, and the lighting calculation software RELUX was used to perform simulations with the data file of this measurement. For two-lane (two way) concrete paved roads, six LED engine are applied to each streetlight and simulation results show that Uo (uniformity) 0.56, UI (longitudinal uniformity) 0.86 and TI (threshold iIncrement) 9% which satisfies the required standards. RELUX was also used to LED streetlights by designing them in three dimensions, that is ${\pm}25%$ of the arm length of 2.8 m standardized by the road lighting standards of the Korea Expressway Corporation. Comparative analysis was carried out on adjustments were made in increments of 0.1 m that Uo, UI, and TI values in the range of arm lengths from 2.1 m~3.5 m. For the arm length range of 2.1 m~2.4 m, Uo was high, whereas UI was low. Therefore, we present the optimal light distribution values designed for an arm length of 2.5 m.