• 한국수소및신에너지학회논문집
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• 제22권4호
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• pp.443-450
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• 2011

The three-reactor chemical-looping process (TRCL) for the production of hydrogen from natural gas is attractive for both $CO_2$ capture and hydrogen production. In this study, redox property of $Fe_2O_3$ and $WO_3$ supported with $ZrO_2$ and $MgAl_2O_4$ were studied with temperature programmed oxidation/reduction (TPO/R) experiment. All metal oxides were prepared by ball mill method. Metal oxides supported with $ZrO_2$ showed the good redox property in TPO and TPR tests. Reduction behavior was matched well the theoretical reduction mechanism. Metal oxides supported with $MgAl_2O_4$ formed a solid solution ($MgFe_{0.6}Al_{1.4}O_4$, $MgWO_4$). $Fe_2O_3$ showed more narrow reaction range and lower reaction temperature than $WO_3$.

• 성인간호학회지
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• 제12권3호
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• pp.477-489
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• 2000

The purpose of study was to assess how hospital nurses practice their health promoting lifestyle and to identify affecting factors. The subjects were 286 nurses working at three general hospitals in Kwang-ju. The data were collected by questionnaire from September 1st. to September 10th, 1999. The instruments for this study were the Health Promoting Lifestyle Profile developed by Walker et al., perceived health status scale developed by Ware et al., self-efficacy scale developed by Sherer et al., and social support scale developed by Cohen et al.. The data were analyzed with mean, standard deviation, t-test, ANOVA, Pearson's Correlation Coefficient and Stepwise Multiple Regression. The results of this study were as follows: 1. The mean score of health promoting lifestyle was 2.36. Interpersonal support showed the highest score(2.67) and health responsibility (1.92) showed the lowest score. The mean score of perceived health status was 3.07, self-efficacy was 2.62, and social support was 2.91. 2. The relationship between general characteristics of subjects and health promoting lifestyle showed significant differences according to duty cycle(t=4.15, p=.042), disease experience (t=5.18, p=.023), monthly income(F=3.13, p=.025), exercise frequency(F=9.12, p=.000), stress reliefe method(F=5.98, p=.000), job satisfaction(t=11.44, p=.000), and perceived fatigue(F=6.13, p=.002). 3. Health promoting lifestyle showed significant positive correlations with perceived health status (r=.2190, p=.0002), self-efficacy (r=.5137, p=.0001) and social support (r=.5181, p=.0001). 4. The combination of social support(27.1%), exercise frequency(10.4%), self-efficacy(8.8%), job satisfaction, perceived health status, perceived fatigue and explained 53.5% of the variance of health promoting lifestyle. Therefore, this study suggests that a replicate study is needed until more affecting factors other than health promoting lifestyle.

• 한국의류산업학회지
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• 제11권3호
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• pp.453-459
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• 2009

The purpose of this study was to provide the basic knowledge to determine the proper seam finish according to the design of sewing products. Four seam finishes(no seam finishes, over-edged seam finishes, turned-and-stitched seam finishes, and bias-bound seam finishes) were constructed with seams in warp, weft and bias directions of the fabric. Using a drape measurement system involving two 18cm diameter supporting disks and a digital camera, the images of draped specimens were captured and processed. Drape behavior was evaluated in terms of drape coefficient, node number, and drape profile. Drape coefficients of the fabrics increased with seam formation and varied by the seam finishes, however no significant differences in drape coefficients by the seam finishes were observed on the heavier fabric. Node numbers of heavier fabric were more deeply affected by the seam finishes than those of lighter fabric. The specimens with turned-and-stitched seam finishes and bias-bound seam finishes showed significantly smaller node numbers compared to the specimens with no seam finishes and over-edged seam finishes on heavier fabric. The length of the seamed part showed positive correlation with the weight of the specimens and negative correlation with the number of nodes in each seam direction. The maximum length of all draped specimens was found in the same direction as the seam direction. In the case of the lighter fabric, the seam and the seam finish had a great influence on the shape of the draped profile.

• Fisheries and Aquatic Sciences
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• 제13권2호
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• pp.140-149
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• 2010

We determined the seasonal gonad maturation in Strongylocentrotus nudus sea urchins inhabiting an artificially enhanced seaweed forest along the Samchuk Coast of Korea from April 2006 to March 2007. A total of 30 sea urchins per month were collected from the study area, and gonadosomatic index (GSI), gonad index (GI), egg diameter, and RNA/DNA variation were measured for each specimen. GSI values of female and male urchins achieved maximums of 17.6 and 17.0, respectively, in June. Based on histological studies, maximum GI values occurred in July (4.6 for females and 4.8 for males). A mean ovarian egg diameter of $73.7\;\pm\;14.2\;{\mu}m$ was measured in August; during the main spawning period in September, mean egg diameter reached a maximum of $74.2\;\pm\;17.8\;{\mu}m$. The RNA/DNA ratio and RNA content for both males and females showed a distinct peak during the ripe stage in July, but another peak occurred in the spring season from March to April, when urchins deposit protein into the nutritive phagocytes of immature gonads prior to gametogenesis. The reproductive cycle of S. nudus is divided into five stages: early active (December-May), late active (March-July), ripe (July-September), spent and degenerative (August-November), and inactive (October-February). Our continuous removal of sea urchins from the study area did not influence the reproductive cycle, as populations quickly recovered, and achieved normal gonad development cycle in the site.

• 정보처리학회논문지B
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• 제12B권3호
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• pp.247-256
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• 2005

컴퓨터 비젼에 관한 고전적인 연구 주제들 중의 하나는 두 개 이상의 이미지로부터 3차원 형상을 재구성하는 3차원 변환에 관한 것이다. 본 논문은 단안 카메라로 촬영한 일반적인 2차원 영상물에서 능동적으로 움직이는 3차원 영상의 깊이 정보를 추출하는 문제를 다룬다. 연속하는 프레임들간의 영상 블록의 움직임을 평가하여 카메라의 회전과 배율효과를 보상하고 다음과 같은 두 개의 단계에 걸쳐 블록의 움직임을 추출한다. (i) 블록의 위치와 움직임을 이용하여 카메라의 이동과 초점거리에 대한 전역 파라메타를 계산한다. (ii) 전역 파라메타, 블록의 위치와 움직임을 이용하여 평균 영상 깊이에 대한 상대적인 블록의 깊이를 계산한다. 다양한 동영상을 대상으로 특이점인 경우와 그렇지 않은 경우를 실험하였다. 결과로 얻어지는 상대적인 깊이 정보와 객체는 인간이 판단하는 경우와 동일함을 보였다.

• Korean Chemical Engineering Research
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• 제54권4호
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• pp.453-458
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• 2016

고분자전해질 연료전지용 MEA (Membrane and Electrode Assembly)와 돼지분뇨를 이용해 미생물연료전지(MFC)를 구동하였다. 미생물 연료전지에서 과불소계막과 탄화수소막의 성능을 비교하였다. 탄화수소막으로 sPAES 막을 사용하였고 과불소계막은 Gore 막을 사용했다. sPAES MEA가 Gore MEA보다 OCV는 50mV 높았고 출력 밀도는 비슷했다. sPAES 막을 강화시킴으로써 성능을 안정시킬 수 있었다. 미생물 연료전지의 셀 온도 $45^{\circ}C$에서 최고의 성능을 얻었고 배양액 순환속도 50 ml/min에서 최고의 성능을 얻었다. 최적 조건에서 돼지 분뇨를 이용한 미생물연료전지에서 최고 $1,100mW/m^2$의 출력 밀도가 발생하였다.

• Korean Chemical Engineering Research
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• 제51권6호
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• pp.671-676
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• 2013

최근에 대용량 에너지 저장 시스템으로 레독스 흐름전지(Redox Flow Battery, RFB)가 활발히 연구 개발되고 있다. 불소계막을 대신할 저가의 탄화수소막이 RFB막으로 주목받고 있다. 본 연구에서는 Poly(arylene ether sulfone) (PAES) 막을 사용해 고가의 불소계막과 그 특성을 바나듐 레독스 흐름전지(VRB, Vanadium Redox Flow Battery)조건에서 비교하였다. 바나듐 이온투과도, 이온 교환 용량, OCV 변화, 팽윤, 충 방전 곡선, 에너지 효율 등을 측정했다. PAES 막은 Nafion 117막에 비해 바나듐 이온투과도가 낮고, 이온교환용량은 커서 Nafion 117을 사용한 RFB보다 에너지 효율이 높았다.

• 한국지역사회생활과학회지
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• 제20권3호
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• pp.343-355
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• 2009

The purpose of this study was to examine the efficacy of child care and the education and the influence of job-stress on job-satisfaction of child care and education teachers. 172 child care and education teachers were chosen from 40 child care centers located in Incheon, Gyeonggido, and Seoul. Data were collected using the efficacy of child care and education index, the job-stress instrument, and the job-satisfaction instrument, and were analyzed using t-test, one-way ANOVA(Duncan test), correlation analysis and multiple regression analysis. There were significant differences in child care and education teacher's job-satisfaction according to the teacher-related variables, including the type of institution, the number of classes, the age of children, the education, the teaching experience, the income, the age of teacher, and the marital status of the teacher. Correlation analysis indicated that the teacher's efficacy of child care and education and the job-satisfaction had significant correlations, especially the satisfaction of job itself indicated high positive correlations. Job-stress and job-satisfaction of the child care and education teachers had significant negative correlations in all sub-variables, especially the stress from the working environment and the satisfaction of administration system indicated high negative correlations. It was also found that stress from the working environment, stress from the overload, stress from the peer relations, and the efficacy of child care and education were all significant predictors of the child care and education teacher's job-satisfaction.

• 대한토목학회논문집
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• 제32권4C호
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• pp.139-147
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• 2012

본 연구에서는 모래의 수급 문제와 회처리장 부족으로 전력생산 위기에 처해진 화력발전소의 문제점을 해결하며, 쇄석다짐말뚝의 폐색 현상에 대처하기 위한 방안으로 모래와 공학적 성질이 유사한 화력발전소 부산물인 저회를 조립재료다짐말뚝 재료로 활용하기 위하여 다양한 공학적 시험을 실시하였다. 특히 연약지반에 쇄석다짐말뚝의 클로깅 현상을 줄이고 말뚝 내 공극을 감소시키기 위한 연구가 수행되었다. 각 재료의 배합비별 전단강도 시험을 통해 적정혼합비를 산정하고 연약지반에 적용 시 효율적인 치환율을 공학적 시험으로 도출하였다. 다짐 시험 및 대형직접전단 시험결과, 쇄석:저회 혼합비 80:20의 전단강도가 가장 크므로 쇄석과 저회 혼합다짐말뚝의 최적 혼합비로 결정하였다. 저회의 혼합비가 20% 이상의 영역에서는 혼합재료의 입자간 맞물림 효과 감소에 의한 내부마찰각 저하가 발생하였다. 동결융해법에 의한 모형시험 방법을 개발하여 압축시험을 수행한 결과, 저회혼합다짐말뚝의 치환율이 40% 이상일 경우 그 영향이 크게 증가하지 않았다. 따라서 저회혼합다짐말뚝을 연약지반에 시공 시 경제적인 치환율은 40%로 판단된다.

• 한국의류학회지
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• 제34권5호
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• pp.775-783
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• 2010

This study examines the dyeability, light fastness, washing fastness, and the antibacterial activity of chitosan and nano silver composite non-woven fabrics dyed with an extracted solution from Chrysanthemum Indicum Linn. The results show that an increase in the chitosan and nano silver percentage resulted in an increase in the $a^*$ values and $b^*$ values; however, the $L^*$ values decreased in the undyed condition. ${\Delta}E$ values of chitosan and nano silver composite non-woven fabrics were higher than cotton 100% non-woven fabrics in the dyed condition with an extracted solution from Chrysanthemum Indicum Linn, and mordant treatments influenced the chrominance change. In the dyed condition with an extracted solution from Chrysanthemum Indicum Linn, an increase in the percentage of chitosan and nano silver resulted in an increase of the K/S values. The dyeability of chitosan and nano silver composite non-woven fabrics increased by mordant treatments. The light fastness and washing fastness of the mordanted non-woven fabrics were better than the non-mordanted. For the antibacterial activity, the bacterial reduction rate of chitosan and nano silver composite non-woven fabrics was 99.9% to Staphylococcus aureus and Klebsiella pneumoniae.