• 대한기계학회논문집B
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• 제36권11호
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• pp.1073-1079
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• 2012

본 논문은 나노유체를 적용하여 써모사이폰 열전달 성능 특성 변화를 실험적으로 규명하는 것을 목적으로 하고 있다. 이를 위하여, 증발부 내부체적을 공유하는 3 개의 독립된 파이프를 가지는 써모사이폰을 제작하였으며 증류수, Ag 나노유체 그리고 $TiO_2$ 나노유체에 대하여 충진량, 증발부에 가해지는 입력열량 그리고 농도변화에 따른 써모사이폰 성능특성 변화를 고찰하였다. 증류수를 작동유체로 사용하는 경우 써모사이폰의 최적충진량은 30%로 결정되었고, $TiO_2$ 나노유체를 적용하는 써모사이폰 열저항이 Ag 나노유체를 적용한 경우에 비하여 평균 18.1% 감소하였다. 또한, 300W 입력열량 및 $TiO_2$ 나노유체 농도 1%에서 써모사이폰의 열전달 성능은 가장 우수하였다.

• Nutrition Research and Practice
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• 제1권4호
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• pp.363-370
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• 2007

Single nucleotide polymorphism (SNP) in adiponectin gene has been associated with insulin resistance, diabetes, and cardiovascular disease (CVD). This study was performed to investigate the association of SNP 276G${\rightarrow}$T at adiponectin gene with CVD risk factors in Korean type 2 diabetes mellitus (DM) patients. The subjects were 351 type 2 DM patients visited a DM clinic in Seoul, and the patients with known CVD were excluded. The adiponectin SNP 276G${\rightarrow}$T was analyzed and dietary intakes were assessed by a Food Frequency Questionnaire. The prevalence of G/G, G/T, and T/T genotype was 47.6%, 43.3%, and 9.1%, respectively. Male subjects with T/T genotype showed significantly lower level of adiponectin and HDL-cholesterol and significantly higher C-reactive protein (CRP) level compared to G/G and G/T genotypes. In G/G genotype, protein intake was negatively correlated to body weight, BMI, and waist circumference, and there were positive correlation between carbohydrate intake and BMI, waist-hip ratio, and ApoB/apoA-1 ratio in G/T genotype. However, in T/T genotype, there was no significant association between macronutrient intakes and anthropometric and hematological values. In conclusion, CVD risk would be high in type 2 DM patients with T/T genotype, and the association of macronutrient intakes with anthropometric and hematologic factors was different among the three adiponectin genotypes. These results may imply the need for different dietary management regime according to adiponectin genotype to lower CVD complications in Korean type 2 DM patients.

• 한국정보시스템학회지:정보시스템연구
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• 제21권1호
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• pp.153-172
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• 2012

The purpose of this study is twofold: first, to identify the factors affecting the relationships between the organizational context for work innovation(organizational citizenship behaviors, IS innovation resistance, and user IT capability) and the intention of ERP extension usage, and second, to examine the mediating effect of the ERP performance on the relationships between the ERP adaptation and the intention of ERP extension usage. In order to achieve the goals of this study, data were obtained from 304 members of the seven organizations such as manufacturers, distributors and service industries, and were analyzed by using SPSS 12.0 and AMOS 5.0. The study results are as follows. There were positive effects of the organizational citizenship behaviors and the user IT capability on the change management activity. The IS innovation resistance had a negative effects on the change management activity. The change management activity had a positive effect on the ERP adaptation. The ERP adaptation had a positive effect on the ERP performance and the intention of ERP extension usage. The ERP performance had a positive effect on the intention of ERP extension usage. In addition, there was a partial mediating effect of the ERP performance on the relationships between ERP adaptation and intention of ERP extension usage. Based on these findings, the implications and limitations of the study were presented including some directions for future studies.

• 한국산학기술학회논문지
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• 제18권4호
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• pp.191-200
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• 2017

본 연구는 시간과 공간의 제약에서 벗어나 효율적으로 일할 수 있는 업무 환경을 만들어 주는 스마트워크의 도입이 기대한 만큼의 성과를 내지 못 하는 것에 대해, 성공적 안착을 위해 가장 주요한 요소로 간주되는 스마트워크에 대한 사용자의 저항을 연구 하였다. 이에 혁신저항 모델을 기반으로 하여 업무의 혁신성과 사용자 특성을 사용자 저항에 영향을 주는 요인으로 설정하였고 이 두 요인과 사용자들의 스마트워크에 대한 저항의 관계를 조절하는 요인으로 사용자가 하는 일의 공간적, 시간적 차원의 자유도를 설정하였다. 검증결과 업무효율성이 낮을수록, 조직의 평가방식이 사용자에게 불리할수록, 그리고 사용자의 기존 업무방식에 대한 만족도가 높을수록 사용자의 저항은 높은 것으로 밝혀졌다. 또한 시간적 자유는 사용자의 특성과 저항 간의 관계에 영향을 미쳤다. 반대로 공간의 자유는 업무의 혁신적인 특성과 저항간의 관계에 영향을 미쳤다. 본 연구의 결과는 성공적인 스마트워크 도입을 위해 기업은 우선적으로 스마트워크 근로자들이 불리해지지 않도록 적절한 비즈니스 프로세스 및 평가 방법을 우선적으로 설정하는 것이 필요하다는 것을 제시한다.

• 품질경영학회지
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• 제42권3호
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• pp.301-310
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• 2014

Purpose: The purpose of this study is to improve a mechanism of expendable bathythermograph measurement by balancing wire resistances between plus wire part and minus wire part and by removing effects of sea water resistance between XBT(Expendable Bathythermograph) and temperature recorder. Methods: The problems are exactly found out through the analysis of XBT and temperature recorder circuit. A process of XBT manufacturing that balances wire resistances between plus wire part and minus wire part is added. Results: The results of this study are as follows; the complicated test process such as temperature accuracy test with a cistern is substituted with a simple process of XBT manufacturing such as balancing wire resistances between plus wire part and minus wire part. Then, the temperature accuracy tolerance of XBT is improved up to ${\pm}0.1^{\circ}C$. Conclusion: Consequently, balancing wire resistances and removing effects of sea water resistance improve temperature accuracy of XBT and reduce expensive and harassing process of XBT manufacturing.

• 한국가금학회지
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• 제19권3호
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• pp.151-160
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• 1992

현재 콕시듐 병의 방제는 약제 투여, 사육관리, 백신을 이용하거나 혹은 이들 방법을 적당히 혼합하여 실시하고 있다. 약제 투여 방법은 약의 내성이라는 문제점을 내재하고 있지만 아직도 콕시듐 방제에 최우선 방법으로 쓰고 있으며 이러한 약제 내성을 조금이나마 지연시키기 위하여 shuttle, 혹은 rotation program을 쓰고 있다. 따라서 약제 내성 검사는 각 농장에 어떠한 약제가 효과가 있는지를 알아보는데 가장 중요한 방법이 되어 왔던 것이다. 콕시듐 방제에 있어서 사육관리에 의한 방법은 아직은 완전한 효과적인 방법으로 정착되지 않았는데 그 이우는 소독제만으로는 콕시듐의 원충을 죽일 수 없기 때문이다. 백신에 의한 방법은 현재까지 살아있는 콕시듐 원충을 제한적으로 쓰고 있는 단계이다. 새로운 형태의 백신개발이 요즈음 연구가 되고 있는데 이 백신은 순화시킨 콕시듐 원충을 사용하거나 유전공학적 방법 혹은 원충의 일부분에 대한 항원을 추출하여 백신으로 이용하는 것이다.

• 벤처창업연구
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• 제9권6호
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• pp.145-152
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• 2014

본 연구에서는 우리나라 의료기기 기업에서 이용 가능한 생체 저항 분석법의 유용성을 비만뿐만 아니라 심혈관질환의 위험성을 예측하고 관리 가능한지를 파악하기 위해 혈액검사와 비교하여 분석하였다. 특히 BIA 측정치 중 인체부위별 겉둘레와 지방두께와의 상관관계를 분석하였다. 본 연구에서는 우리나라 의료기기 산업에 있어 BIA의 활용과 진단을 기반으로 효율적인 관리와 평가를 위해 이용 가능하도록 제안하는데 목적이 있다.

• Toxicological Research
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• 제26권4호
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• pp.301-313
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• 2010

Growth promoters including hormonal substances and antibiotics are used legally and illegally in food producing animals for the growth promotion of livestock animals. Hormonal substances still under debate in terms of their human health impacts are estradiol-$17\beta$, progesterone, testosterone, zeranol, trenbolone, and melengestrol acetate (MGA). Many of the risk assessment results of natural steroid hormones have presented negligible impacts when they are used under good veterinary practices. For synthetic hormonelike substances, ADIs and MRLs have been established for food safety along with the approval of animal treatment. Small amounts of antibiotics added to feedstuff present growth promotion effects via the prevention of infectious diseases at doses lower than therapeutic dose. The induction of antimicrobial resistant bacteria and the disruption of normal human intestinal flora are major concerns in terms of human health impact. Regulatory guidance such as ADIs and MRLs fully reflect the impact on human gastrointestinal microflora. However, before deciding on any risk management options, risk assessments of antimicrobial resistance require large-scale evidence regarding the relationship between antimicrobial use in food-producing animals and the occurrence of antimicrobial resistance in human pathogens. In this article, the risk profiles of hormonal and antibacterial growth promoters are provided based on recent toxicity and human exposure information, and recommendations for risk management to prevent human health impacts by the use of growth promoters are also presented.

• Journal of Advanced Marine Engineering and Technology
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• 제40권2호
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• pp.96-101
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• 2016

The thermal management of high-power LED components in an assembly structure is crucial for the stable operation and proper luminous function. This study employs numerical tools to determine the optimum thermal design in LEDs with a heat sink consisting of a crevice-type vapor-chamber heat pipe. The effects of the MCPCB are investigated in terms of the substrate thicknesses on which the LEDs are mounted. Further, different placement configurations in a system module are considered. This study found that for a confined area, a power of 40 W/LED is applicable to a high-power package. Furthermore, the thermal conductivity of dielectric layer materials should ideally be greater than 0.9 W/m.K. The temperature conditions of the vapor chamber in a heat pipe greatly affect the thermal performance of the system. At an offset distance of 9.0 mm and a $2^{\circ}C$ increase in the temperature of the heat pipe, the resulting maximum temperature increase is approximately $1.9^{\circ}C$ for each heat dissipation temperature. Finally, at a thermal conductivity of 0.3 W/m.K, it was found that the total thermal resistance changes dramatically. Above 1.2 W/m.K, the resistance change reduces exponentially.

• 한국전기전자재료학회논문지
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• 제31권7호
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• pp.515-520
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• 2018

A large number of lithium-ion batteries are arranged in series and parallel in battery packs, such as those in electric vehicles or energy storage systems. As battery packs age, their output power and energy density drop because of voltage deviation, constant and non-uniform exposure to abnormal environments, and increased contact resistance between batteries; this reduces application system efficiency. Despite the balancing circuit and logic of the battery management system, the output of the battery pack is concentrated in the most severely aged unit cell and the output is frequently limited by power derating. In this study, we implemented a cell imbalance detection algorithm and selected parameters to detect a sudden decrease in battery pack output. In addition, we propose a method to increase efficiency by applying the measured testing values considering the operating conditions and abnormal conditions of the battery pack.