• Journal of the Korean Ceramic Society
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• v.36 no.8
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• pp.791-798
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• 1999

The preparation method of yttria-stabilized zirconia(YSZ) thin film for an anode support type solid oxide fuel cell(SOFC) by electrophoretic deposition(EPD) and dip-coating was studied. And the difference in both preparation method was investigated through basic understanding of processing parameters which may significantly affect weight microstruxcture and defect of film. In dip-coating the thickness of film increased with time until 30 s and then the weight of film decreased with time due to particle falling off from the coagulated film. In EPD although the weight of film increased with time and applied constant-current sagging of the film was observed when the applied current was less that 0.035 mA/$cm^2$ and more than 120 s. Since YSZ thin film by EPD on porous substrate was dense smooth and homogeneous it was expected to be suitable for the electrolyte of an anode support type SOFC.

• Journal of agricultural medicine and community health
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• v.24 no.2
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• pp.351-368
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• 1999

The objective and subjective burden was evaluated toward 115 main caregivers in the family with schizophrenic patient by interview with structured questionnaire and self-report using Family Burden Scale (FBS) of family with schizophrenic patient in Korea. The results were as follows : 1) The mean age of onset by schizophrenic patient were 23 years old in male and 26 in female. 2) The mean scales of objective and subjective burden were 1.5 and 1.6. 3) By Logistic regression objective burden was significantly affected by family support (P<0.001), religion (P<0.05), occupation (P<0.05). 4) Subjective burden was significantly affected by family support (P<0.01) and family total income (P<0.05). 5) Total objective and subjective burden was significantly affected by family support (P<0.001), religion (P<0.05). In conclusion, this study suggests that main caregivers need family support from other family members. For them religion and social support are also helpful to cope with the burden to take care of the schizophrenic patients.

• Journal of the Korean Chemical Society
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• v.32 no.6
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• pp.593-602
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• 1988

Polymer-supported crown ethers (Ps-CE) which can be used for phase-transfer catalyst (PTC) were synthesized for the purpose of allowing reusable function to ordinary crown ethers, and the kinetics of the liquid-solid-liquid triphase-catalyzed nucleophilic displacement reaction of iodide (aqueous phase) on 1-bromooctane (organic phase) using synthesized Ps-CE (solid) were studied. Ps-CE were obtained by grafting of hydroxymethyl crown ethers to 1~2% cross-linked chloromethylated polystyrene. All reactions followed a pseudo-first order dependency on the 1-bromooctane concentration and the observed rate constants $(k_{obsd})$ were linearly related to the molar equivalents of Ps-CE, and were subjected to the influence of cross-linking density of polymer backbone, solvent and the reaction temperature. The catalytic activity of Ps-CE was also compared with that of structurally similar soluble crown ethers, and used Ps-CE were easily recovered after the reaction by simple filtration and could be reused without loss of catalytic activity in the same anionic displacement reaction. Enthalpies and entropies of activation associated with the displacement were 10~20kcal $mol^{-1}, 20~55eu. respectively, and the free energy of activation was ~30kcal mol^{-1}$.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.562-566
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• 2006

최근 들어 국내에서는 도서지방을 잇는 연육교와 해상구간을 통과하는 대형교량의 건설이 활발히 진행되면서 해상조건에서 발생하는 교량세굴에 대처하기 위한 연구의 중요성이 대두되고 있다. 그러나 아직까지 해상조건의 세굴현상을 파악하기 위한 적절한 세굴평가 기준이 제시되어 있지 않고 대부분 자연 하천교량 기준에 의해 해상교량의 세굴평가가 이루어지고 있는 실정이다. 교량에서 발생하는 세굴 현상은 교량 기초의 안정성에 치명적인 영향을 줄 수 있고 나아가서는 교량의 붕괴 원인이 될 수 있다. 또한 교량기초 지반의 지지력 부족이나 적정피복두께 결여 등의 원인으로 구조적인 문제점을 초래할 수 있다. 해상교량의 경우에는 조석에 의한 왕복류, 파 흐름의 상호작용, 점착성 지반 등 세굴에 영향을 미칠 수 있는 요인들이 복합적으로 작용하므로 교량 건설 전부터 해상조건을 반영한 다각적인 세굴검토가 요구된다. 본 연구는 강한 조석류가 작용하고 넓은 조간대를 형성하고 있는 인천대교의 세굴심을 합리적으로 산정하기 위하여 다학제적인 연구를 시도한 것이다. 본 연구에서는 해상조건의 침식유발특성을 파악하기 위한 연구로서 수치모형 및 수리모형 실험을 수행하고, 지반종류에 따른 침식저항능력을 파악하기 위한 세굴률 실험을 수행하였다. 더불어 인천대교 건설현장에 타설되어 있는 대구경 시험말뚝에 대한 실시간 세굴모니터링을 실시하여 얻은 현장관측 자료를 검증자료로 사용함으로써 종합적인 세굴검토를 통하여 다학제적이고 합리적인 해상교량의 세굴심을 평가하고자 한다.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.12 no.2
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• pp.125-140
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• 2001

As an attempt to grasp the current situation of traditional Korean books scattered about in the world, this study has bibliographically analyzed first of all traditional Korean books as well as old Korean maps and atlases, and topography descriptions collected by L. C.. Traditional Korean books have been analyzed classified by subject, printing or manuscript, and the kind of edition. Historical development in the compilation of geographical materials during the Chosun Dynasty has been studied. Especially on old Korean maps and atlases bibliographical characteristics have been researched. Accordingly. the foundation has been laid not only for the study on the bibliographical characteristics and the current situation of traditional Korean books and old Korean maps and atlases but also for the comparative analysis on traditional Korean books in Korea with the ones collected by L.C.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.10
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• pp.667-673
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• 2017

We investigated the temperature uniformity in an anode-supported solid oxide fuel cell, using the open source computational fluid dynamics (CFD) toolbox, OpenFOAM. Numerical simulation was performed in three different flow paths, i.e., co-flow, counter-flow, and cross-flow paths. Gas flow in a porous electrode was calculated using effective diffusivity while considering the effect of interconnect rib. A lumped internal resistance model derived from a semi-empirical correlation was implemented for the calculation of electrochemical reaction. The result showed that the counter-flow path displayed the most uniform temperature distribution.

• Journal of agricultural medicine and community health
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• v.41 no.1
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• pp.13-26
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• 2016

Purpose: This study was performed to identify the association between family support, activities of daily living (ADL) and depression among hospitalized older patients with chronic diseases. Methods: This study subjects were 100 elderly patients with chronic diseases including chronic respiratory diseases, diabetes mellitus and et al. in a general hospital. The collected data were patient characteristics, family support, ADL, and depression by structured questionnaire and medical chart review. The used statistical analyses were t-test, analysis of variance, Pearson's correlational analysis and multiple regression analysis. Results: The mean scores of family support, ADL and depression were $49.95{\pm}8.68$, $8.65{\pm}2.65$, $6.66{\pm}3.78$, respectively. The prevalence rate of depression was 64.0%. In simple analysis, the statistically significant associated factors with depression were age, spouse, economic status, social activity, subjective health status, and number of pain. Depression had statistically a significant positive correlation with ADL and a negative correlation with family support. The final result of hierarchial multiple regression analysis (Model 3), the factors related to depression were family support (b=-.135, p<.001), subjective health status (b=2.510, p=.001). Conclusions: It is necessary to develop and apply the program for controlling the depression of elderly patients with health education, reinforcement of supportive systems in hospital. And, further multidisciplinary studies should be done.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.227.1-227.1
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• 2010

본 연구는 자외선 영역의 흡수로 전자 정공의 전하쌍을 생성함으로써 광전압 및 전류를 일으키는 티타니아 물질을 금속지지체 표면에 양극산화로 튜브형 $TiO_2$(anodized tubular $TiO_2$; ATT)로 제조한 후 나노크기의 금속 혹은 $WO_3$입자를 담지하여 광감응 재료로 활용하였다. 이는 기존의 입자나 콜로이드 형태로 광촉매 물질을 고정화하여 사용한 재료의 탈리현상 및 효율저하를 극복하기 위함이다. ATT는 전해질 내에 전기화학적 에칭율과 화학적 용해율의 비율에 의해 나노튜브 길이 성장에 영향을 미치는데 이를 유기 전해질과 불산 전해질을 사용하여 정전압 혹은 정전류의 조건에서 다양한 길이의 $TiO_2$ 나노튜브를 제조하였다. 여기에 전기분해담지(electrolytic deposition; ELD)를 통하여 정전류 조건에서 다양한 금속(Pt, Pd, Ru)을 나노크기의 형태로 담지하여 광촉매 내 생성된 전자 정공의 재결합을 줄이고자 하였고 $WO_3$의 담지를 통하여 가시광 감응을 높이고자 하였다. 제조된 여러 조건의 시료는 SEM과 EDAX를 통하여 형태와 길이, 담지량을 확인 하고 XRD를 이용하여 열처리 온도에 따른 결정화상태를 확인하였으며 광전류 측정 및 Cr(VI)의 광환원과 MB의 광분해를 통하여 광효율을 관찰하였다. 금속이 도핑되었을 경우 순수 ATT보다 보통 3배의 흡착률과 UV광원 아래 2배의 광효율을 관찰할 수 있었는데 이 중 Pt의 담지가 가장 효율이 좋았으며 흡착률에서는 담지량의 증가에 따른 증가선을 관찰 할 수 있었으나 광원 사용시 3%담지율에서 최적을 확인 할 수 있었다. 또한 $TiO_2$외 가시광감응 활성을 높이기 위한 다양한 광촉매제조가 진행 중에 있다.

• Journal of Conservation Science
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• v.38 no.3
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• pp.192-200
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• 2022

This study aimed for species identification and tree-ring dating and radiocarbon dating of wooden warehous materials excavated from Baengnyeongsanseong in Geumsan. The species of 83 wooden materials were identified as 38 Platycarya spp., 34 Cerris Section, 8 Prinus section, 2 Hard pine, and 1 Kalopanax pictus. After cross-dating of 5 Cerris Section samples with the TSAP program, one Cerris Section chronology (GSQU 1S) was constructed. To identify the exact date, one material which show many tree-ring (GSQU 05) was analyzed by radiocarbon dating using wiggle match. As a result of radiocarbon dating, the outermost edge of east beam (GSQU 05) was found to be A.D. 575-655 or A.D. 665-685. The radiocarbon dating of wooden warehouse material was consistent with the archaeologically estimated date.

• Journal of agricultural medicine and community health
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• v.46 no.4
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• pp.253-265
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• 2021

Objectives: The aim of the study is to identify the success factors of 6 months of smoking cessation targeting male workers in small and medium-sized businesses. Methods: The subjects of this study were smoking male workers who had got the visiting services at a tobacco control center to stop smoking from January 2018 to December 2020. Total number of the participants was 767. Results: The male workers in small and medium enterprises had a success rate of 20.2% for smoking cessation for 6 months. With multiple logistic regression, the factors causing the differences in the success rate for 6 months of the workers were as follows. - The odds ratios (ORs)(95% confidence interval, CI) of the age group of under 29 and 40-49 years were 0.10 (0.03-0.29) and 0.43 (0.24-0.76), respectively, compared to the 50 years and older group. The ORs (95% CI) of the daily average of smoking group of 11-20 and more than 21 were 0.52(0.34-0.80) and 0.46(0.24-0.90), respectively, when compared to the group of 1-10. The ORs (95% CI) of the supporting persons for quitting smoking group of with spouse and other family were 1.99(1.18-3.34), compared to the group with no one. Conclusions: This study showed that the chance of success for smoking cessation for 6 months is higher when the subjects have spouses and other family Supporting persons for quitting smoking. And it also shows that the less they smoke a day and the older they are, the more likely it is to succeed in quitting smoking.