• 설비공학논문집
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• 제20권9호
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• pp.571-580
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• 2008

In this work, pool boiling heat transfer coefficients(HTCs) of 5 refrigerants of differing vapor pressure are measured on horizontal smooth square surface of 9.52 mm length. Tested refrigerants are R123, R152a, R134a, R22, and R32 and HTCs are taken from $10\;kW/m^2$ to critical heat flux of each refrigerant. Wall and fluid temperatures are measured directly by thermocouples located underneath the test surface and by thermocouples in the liquid pool. Test results show that pool boiling HTCs of refrigerants increase as the heat flux and vapor pressure increase. This typical trend is maintained even at high heat fluxes above $200\;kW/m^2$. Zuber's prediction equation for critical heat flux is quite accurate showing a maximum deviation of 21% for all refrigerants tested. For all refrigerant data up to the critical heat flux, Stephan and Abdelsalam's well known correlation underpredicted the data with an average deviation of 21.3% while Cooper's correlation overpredicted the data with an average deviation of 14.2%. On the other hand, Gorenflo's and lung et al.'s correlation showed only 5.8% and 6.4% deviations respectively in the entire nucleate boiling range.

• 한국태양에너지학회 논문집
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• 제31권6호
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• pp.49-56
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• 2011

In this study a novel cogeneration system driven by low-temperature sources at a temperature level below $190^{\circ}C$ is investigated by first and second laws of thermodynamics. The system consists of Organic Rankine Cycle(ORC) and an additional heat generation as a parallel circuit. Seven working fluids of R143a, R22, R134a, R152a, $iC_4H_{10}$(isobutane), $C_4H_{10}$(butane), and R123a are considered in this work. Maximum mass flow rate of a working fluid relative to that of the source fluid and optimum turbine inlet pressure are considered to extract maximum power from the source. Results show that due to a combined heat and power generation, both the efficiencies by first and second laws can be significantly increased in comparison to a power generation, however, the second law efficiency is more resonable in the investigation of cogeneration systems. Results also show that the working fluid for the maximum system efficiency depends on the source temperature.

• 산학경영연구
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• 제16권
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• pp.123-144
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• 2003

R&D 성과이전은 좁은 의미의 기술이전 형태이다. 본 연구는 기술개발 아이디어 탐색으로부터 시장진입에 이르는 R&D 성과이전을 효과적으로 수행하는데 유용한 관리시스템의 구성을 연구하였다. 이를 위해 본 연구는 기술이전의 특성과 성공요소를 분석하고 실험실 연구결과를 사업화 하는 학술적 기업가의 실험실 창업프로젝트의 수명주기를 7단계로 구분하고 사례연구를 통해 위험유형을 각 단계별로 탐색하였다. 이를 바탕으로 학술적 기업가의 R&D 성과를 성공적으로 이전하기 위한 전략으로 마케팅 지향적 사고, R&D 참여 당사자간 역할 명시, 학술적 기업가의 역동적 리더십 발휘 시스템 구축, R&D 성과이전 관리시스템 구축, 그리고 프로젝트 위험관리기법의 사용 등을 제시하였다.

• Interdisciplinary Bio Central
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• 제4권4호
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• pp.12.1-12.6
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• 2012

The advanced glycation endproducts receptor (AGE-R) is a signal transduction receptor for multiligand such as S100b and AGEs. S100b has been demonstrated to activate various cells with important links to atherosclerosis initiation and progression including endothelial cells, and smooth muscle cells via AGE-R, triggering activation of multiple signaling cascades through its cytoplasmic domain. Many studies have suggested AGE-R might even participate in the cardiovascular complications involved in the pathogenesis of type I diabetes. Recently, Small Ubiquitin-Related Modifier 1 (SURM-1 also known as SUMO-1) has been recognized as a protein that plays an important role in cellular post-translational modifications in a variety of cellular processes, such as transport, transcriptional, apoptosis and stability. Computer Database search with SUMOplot Analysis program identified the five potential SURMylation sites in human AGE-R: K43, K44, K123, and K273 reside within the extracellular domain of AGE-R, and lastly K374 resides with the cytosolic domain of AGE-R. The presence of the consensus yKXE motif in the AGE-R strongly suggests that AGE-R may be regulated by SURMylation process. To test this, we decided to determine if AGE-R is SURMylated in living vascular cell system. S100b-stimulated murine aortic vascular smooth muscle cells were used for western blot analysis with relevant antibodies. Taken together, bioinformatics database search and molecular biological approaches suggested AGE-R is SURMylated in living cardiovascular cell system. Whilst SURMylation and AGE-R undoubtedly plays an important role in the cardiovascular biology, it remains unclear as to the exact nature of this contribution under both physiological and pathological conditions.

• 멤브레인
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• 제24권2호
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• pp.123-135
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• 2014

고도정수처리를 위한 관형 세라믹 정밀여과와 이산화티타늄($TiO_2$) 광촉매 첨가 PES (polyethersulfone) 구의 혼성공정에서 pH 및 포화산소, 역세척 매체의 영향을 막오염에 의한 저항($R_f$) 및 투과선속(J), 총처리수량($V_T$) 측면에서 물 또는 질소, 산소 역세척 결과를 비교하였다. pH가 증가할수록 $R_f$는 감소하였고 J과 $V_T$는 증가하였다. 탁도 처리효율은 pH에 상관없이 물 또는 질소 역세척 모두 유사한 값을 보였고, 용존유기물(DOM) 처리효율은 물 역세척 시 일정한 경향을 보이지 않았다. $R_f$는 공급수를 산소로 포화시킨 무역세척(NBF)에서 포화산소(SO)가 없는 NBF보다 낮게 나타났다. DOM 처리효율도 SO가 있는 NBF에서 SO가 없는 NBF보다 낮게 나타났다. 이러한 결과는 SO가 광촉매 $TiO_2$와 반응하여 발생된 OH 라디칼이 모듈 내에 채워진 물에 의해 희석되었기 때문이다. 역세척 주기 10분에서 물 역세척보다 기체 역세척 시 DOM 처리효율은 큰 값을 보였다. 이러한 결과는 기체 역세척이 물 역세척보다 PES 구를 효과적으로 세척함으로써, PES 구에 의한 흡착과 광분해가 활발하게 진행되기 때문이다.

• Journal of Nutrition and Health
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• 제34권2호
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• pp.123-131
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• 2001

The purpose of this study was to investigate the effects of diet composition on serum leptin and lipids profiles in rats. At the baseline, seven 4-week-old Sprague-Dawley rats, male, were sacrificed and the remaining rats were divided into five groups and each group was fed one of the following five dietary regiments for 2 weeks and 6 weeks;the control diet AIN76(CAL, n=2l), high-carbonhydrate(rice)(HCR, n=2l), high-carbohydrate(flour)(HCF, n=2l), high-fat(corn oil)(HFO, n=2l), high-fat(beef tallow)(HFB, n=2l). Serum leptin was determined by a double antibody ELISA assay at the baseline(n=7), 6 week(n=35) and 10 week of age(n=70). At 6 weeks of age, the increase in the Food Efficiency Ratio(FER) was related to adipocyte hyperplasia in rats on HFB diets. The serum triglyceride, total cholesterol, and LDL-cholesterol increased significantly in HFB group, and decreased in HFO group compared to control group. The HFC group showed significant increase in serum triglyceride level compared with control group. After 2 weeks and 6 weeks, noticeably high increases in epididymal adipose tissue fat cell mass and numbers were observed with the HFB fed group. Serum leptin levels increased as body weight increased over the period of time(4weeks; 1.50$\pm$0.13ng/ml versus 10weeks; 2.08$\pm$-.13ng/ml). And this result shows that there are 193% higher in rats fed high fat-beef tallow diet than the control diet. Serum leptin levels of the HFB group(4.01$\pm$0.39mg/ml) were significantly higher than that of the HFO(2.06$\pm$0.5613ng/ml), CAL(2.08$\pm$0.1313ng/ml), HCR(2.41$\pm$0.2113ng/ml) and HCF(2.80$\pm$0.4713ng/ml) at p<0.05. The serum leptin concentration was positively correlated with the amount of epididymal fat pads(r=0.47 p<0.01), serum triglyceride(r=0.49, p<0.001), tatal cholesterol(r=0.48, p<0.001), LDL-cholesterol(r=0.58, p<0.001), atherogenic index(r=0.67, p<0.001), and inversely correlated with HDL-cholesterol(r=-0.65, p<0.001). In conclusion, the changes in composition of dietary fat and carbohydrate intake could affect changes in concentration of serum lipids and leptin. Especially, the high-fat diet with animal fat source could increase circulating leptin level. (Korean J Nutrition 34(2) : 123-131, 2001)

• 한국산학기술학회논문지
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• 제21권4호
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• pp.109-116
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• 2020

본 연구는 간호대학생의 진로동기, 유머감각, 문제해결능력이 정신건강에 미치는 영향을 확인하여 정신건강을 향상시키기 위한 기초자료를 제공하기 위하여 시도되었다. 연구대상자는 B, Y시의 간호대학생 253명을 대상으로 하였다. 자료수집은 2018년 10월 22일부터 10월 31일까지 였다. 수집된 자료는 SPSS 22.0 program을 이용하여 실수, 백분율, 평균, 표준편차, t-검증, 일원분산분석, 피어슨 상관계수, 다중회귀분석으로 분석하였다. 연구결과 대상자의 정신건강은 평균 2.19±0.77점으로 나타났다. 대상자의 일반적 특성에 따른 정신건강의 차이는 성별(F=2.219, p=.027), 학년(F=7.142, p<.001), 용돈(F=5.055, p=.007), 학교 성적(F=4.322, p=.014), 동료와의 관계(F=23.561, p<.001), 건강상태(F=21.555, p<.001)에서 유의한 차이가 나타났다. 대상자의 정신건강은 진로동기(r=-.443, p<.001), 유머감각(r=-.400, p<.001), 문제해결능력(r=-.465, p<.001)와 부적 상관관계를 나타냈다. 대상자의 정신건강에 영향을 미치는 요인은 성별(β=-.121, p=.033), 용돈(β=.123, p=.028), 동료와의 관계(β=.165, p=.004), 유머감각(β=-.168, p=.012), 문제해결능력(β=-.186, p=.006)으로 나타났고, 설명력은 33.6%로 나타났다. 본 연구결과를 통하여 간호대학생의 정신건강에 영향을 미치는 다양한 요인을 확인하는 연구가 필요하다. 또한 일반적 특성, 자신을 조절할 수 있는 심리적 요인, 학습을 통해 획득할 수 있는 기술적인 요인을 확인하는 반복연구를 통해 정신건강을 향상시킬 수 있는 중재방안을 개발하는 것이 필요하다.

• 한국해양학회지:바다
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• 제12권3호
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• pp.225-233
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• 2007

Small subunit ribosomal RNA (18S rRNA)의 loop 부위들의 변이를 분석하여 해양 섬모충류의 종 특이 유전적 마커로써 이용 가능성을 확인하고자 9종의 Euplotes (Hypotrichia : Ciliophora)에 대하여 18S rRNA 유전자의 염기서열 변이성을 조사하였다. 연구 결과에 의하면 V1, V3 그리고 V5 부위는 종간 변이가 없었고, V7과 V8은 종간변이는 높으나 염기서열의 길이가 각각 44 bp와 79 bp로 길이가 짧아서 충분한 유전 정보를 가지기 어렵기 때문에이 부위들은 종특이 분자마커로 적합하지 않았다. 그러나 V2와 V4부위는 $1.75{\sim}20.61%$로 높은 변이성을 보여주었고 종간 계통 관계도 잘 나타내었다. 또한 염기서열의 길이도 각각 123 bp와 306 bp로 마커 개발에 충분한 길이를 가지고 있었다. 따라서 18S rRNA의 V2와 V4부위는 섬모충류의 종 특이 분자 마커 개발에 가장 적합한 부위라는 결론을 얻었다.

• 종양간호연구
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• 제11권3호
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• pp.237-246
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• 2011

Purpose: The aim of this study was to investigate the relationships between stigma, distress, and quality of life (QOL) in patients with lung cancer. Methods: The subjects of the study were 123 lung cancer patients who visited the outpatient department of S hospital in Seoul from July 21st to August 29th, 2011. To measure stigma, distress, and QOL, Cataldo Lung Cancer Stigma Scale, Hospital Anxiety and Depression Scale (HADS), and EORTC QLQ-C30 (Quality of Life Questionnaire, Core 30) were used in this study. The collected data were analyzed using frequency, average, t-test, ANOVA, and Pearson correlation with SPSS WIN 19.0. Results: Stigma showed positive correlations with anxiety, depression, and symptom (r=.37, p<.001; r=.44, p<.001; r=.23 p=.012), while it showed negative correlations with global QOL and function (r=-.26, p=.003; r=-.40, p<.001). Anxiety and depression also positively correlated with symptoms (r=.43, p<.001; r=.58, p<.001) while anxiety and depression negatively correlated with global QOL (r=-.40, p<.001; r=-.56, p<.001) and function (r=-.64, p<.001; r=-.66, p<.001). Conclusion: The findings of the study demonstrated that lung cancer patients experienced stigma and distress that had a negative influence on the subjects' QOL. Thus the study's findings can be useful in developing psychosocial nursing strategies to improve QOL of lung cancer patients in the future.

• 대한수학회논문집
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• 제26권4호
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• pp.543-549
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• 2011

In 1945, the notion of free lattice over a poset was introduced by R. Dilworth (Trans. Am. Math. Soc. 57 (1945), 123{154). In this note, a construction of the free algebra over a poset in varieties finitely generated is shown. Finally, this result is applied to different classes of algebras.