• 한국가스학회:학술대회논문집
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• 한국가스학회 2000년도 추계학술발표회 논문집
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• pp.232-243
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• 2000

• 설비공학논문집
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• 제24권8호
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• pp.636-645
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• 2012

The performance of various type plate exchangers with different chevron angle, dimple size and arrangement was analysed by using Ansys v13.0. Heat transfer performance, pressure drop and flow patten of plate heat exchanger were investigated according to mass flow ratio investigated and compared. As a result, the $60^{\circ}$-chevron type plate heat exchanger showed the highest heat transfer performance but pressure drop was relatively high. The efficiency of $45^{\circ}$-chevron type plate heat exchanger showed the best performance in considering of heat transfer performance and pressure drop simultaneously. Among dimple type plate heat exchangers, the highest heat transfer performance was shown in a dim_zigzag type plate heat exchanger but pressure drop was very high. Besides, the dim_upsize plate heat exchanger showed very low pressure drop.

• 디지털융복합연구
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• 제14권3호
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• pp.83-94
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• 2016

본 연구는 중소기업의 기술이전에 영향을 미치는 결정인자가 무엇인지를 분석하여 중소기업의 융복합 경영 전략을 수립하기 위한 기초자료를 제공하기 위한 것이 목적이다. 중소기업을 대상으로 한 2008년부터 2012년까지 기술이전 사례를 지식재산거래정보시스템 등에서 기술거래 데이터를 수집하여 중소기업 기술이전의 결정요인을 로지스틱 회귀분석을 통해 분석하였으며 그 연구결과는 다음과 같다. 첫째, 중소기업 기술이전의 경우 해당 기술 발명자의 수가 많을수록 기술이전의 성공에 긍정적인 영향을 미치는 것으로 나타났고 둘째, 해당 기술의 청구항의 수가 많아질수록 기술이전의 성공률이 제고되었고 셋째, 해당 기술에 대한 피인용문헌의 수가 많을수록 중소기업의 기술이전 성과와 정의 관계가 있는 것으로 나타났다.

• 디지털융복합연구
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• 제16권9호
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• pp.51-61
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• 2018

본 연구의 목적은 국내의 연구개발과 그 결과물의 기술이전, 이전된 기술을 활용한 사업화의 배경적 특징을 반영한 기술이전-사업화 모델을 제시하고자 한다. 이에 기존 연구에서 제시된 기술사업화 모델을 개괄하고, 국내 기술이전 현황과 기술이전 주체의 배경을 조사하여 제시할 모델의 적합성을 밝히고자 한다. 이어서 기술이전-사업화 모델을 제시하고, 이 모델을 적용한 사례를 소개하는 절차로 연구를 진행하였다. 연구결과로 제시하는 기술이전-사업화 모델은 사업화의 각 단계에서 참여 주체별 역할을 제시하면서 추가개발 단계를 중심으로 공급자 주도 영역 영역과 수요자 주도 영역이 구분하였다. 그리고 기술이전 과정에서의 공급자와 수요자 및 중개기관의 역할을 제안하였다. 본 모델의 활용은 기술공급자의 경우 사업화 완료 단계까지 점진적으로 역할을 줄여가는 방식으로, 기술수요자의 경우 제품화 및 수익실현까지 주도적 역할을 점진적으로 확대하는 기업혁신 모델로 삼을 수 있다. 본 연구는 기술이전 주체들의 역할과 주도 수준을 명확히 제시한 점에서 의의가 있으며, 향후 사례로 분석한 기업에 대한 분석을 통해 기술의 적용 및 성과에 대한 연구로 확장하고자 한다.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.407-408
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• 2002

This paper presents a split cooling system for a new inline 4-cylinder automotive engine. The split cooling system circulates coolant to the cylinder head and cylinder block separately. The coolant flow in the cylinder block is controlled by a $2^{nd}$ Thermostat installed at the outlet of cylinder block. The $2^{nd}$ thermostat closes when the coolant temperature is low. And this makes the coolant flow in cylinder block nearly stagnant, thereby reducing the coolant-side heat transfer coefficient and raising cylinder bore temperature. The $2^{nd}$ thermostat starts to open when the coolant temperature reaches a specified temperature. The test results on engine dynamometer show improved fuel economy and lower exhaust emission which result from the decrease in friction works and cooling loss. Also, several vehicle tests, with application of the new engine have been performed. Fuel economy improvement of 0.5{\sim}2.0%$ yields from different test modes and details are discussed in this paper.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.589-595
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• 2001

The present study conducted heat transfer analysis in multi-layer of CD-R. It is necessary to analyze heat transfer during the recording process to find optimum power and write strategy in CD-R. This study investigated effects of several parameters such as recording speed, laser power, layer thickness and thermal property. The calculated results presented temperature distribution in the multi-layer and detailed information of recording characteristics. Optimum laser power was estimated, comparing an optimum mark length with the calculated mark lengths. The results showed that the optimum laser power was influenced significantly by the layer thickness and the thermal properties of the dye.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.163-166
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• 2003

Laser-Induced Thermal Imaging (LITI) is a laser addressed patterning process and has unique advantages, such as high-resolution patterning with over-all position accuracy of the imaged stripes within 2.5 micrometer and scalability to large-size mother glass. This accuracy is accomplished using real-time error correction and a high -resolution stage control system that includes laser interferometers. Here the new concept of mixed hybrid system which complement the advantages of small molecular and polymeric materials for use as an OLED; our system can realize the easy processing of polymers and high luminance efficiency of recently developed small molecules. LITI process enables to pattern the stripes with excellent thickness uniformity and multi-stacking of various functional layers without using any type of fine metal shadow mask. In this study, we report a full-color hybrid OLED using the multi-layered structure of small molecular/polymeric species.

• 한국수정란이식학회지
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• 제29권1호
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• pp.91-99
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• 2014

Oxygen consumption is a useful parameter for evaluating mammalian embryo quality, since individual bovine embryos was noninvasively quantified by scanning electrochemical microscopy (SECM). Recently, several approaches have been used to measure the oxygen consumption rates of individual embryos, but relationship between oxygen consumption and pregnancy rates of Hanwoo following embryo transfer has not yet been reported. In this study, we measured to investigate the correlation between oxygen consumption rate and pregnancy rates of Hanwoo embryo using a SECM. In addition to, the expression of pluripotent gene and anti-oxidant enzyme was determined using real-time PCR by extracting RNA according to the oxygen consumption of in vivo embryo. First, we found that the oxygen consumption significantly increased in blastocyst-stage embryos (blastocyst) compared to early blastocyst stage embryos, indicating that oxygen consumption reflects the embryo quality (Grade I). Oxygen consumption of blastocyst was measured using a SECM and total cell number of in vitro blastocyst was enumerated by counting cells stained by propidium iodide. The oxygen consumption or GI blastocysts were significantly higher than those of GII blastocysts ($10.2{\times}10^{15}/mols^{-1}$ versus $6.4{\times}10^{15}/mols^{-1}$, p<0.05). Total cell numbers of in vitro blastocysts were 74.8, 90.7 and 110.2 in the oxygen consumption of below 10.0, 10.0~12.0 and over $12.0{\sim}10^{15}/mols^{-1}$, respectively. Pregnant rate in recipient cow was 0, 60 and 80% in the transplantation of embryo with the oxygen consumption of below 10.0, 10.0~12.0 and over $12.0{\times}10^{15}/mols^{-1}$, respectively. GPX1 and SOD1 were significantly increased in over -10.0 group than below 10.0 groups but in catalase gene, there was no significant difference. On the other hand, In OCT-4 and Sox2, pluripotent gene, there was a significant difference (p<0.05) between the below-10.0 ($0.98{\pm}0.1$) and over 10.0 ($1.79{\pm}0.2$). In conclusion, these results suggest that measurement of oxygen consumption maybe help increase the pregnant rate of Hanwoo embryos.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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• pp.24-26
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• 1995

The Development of A.C. Induction Motor for Railway Rolling Stock. The traction motor is designed as 4-pole induction motor with self ventilation. The winding insulation is throughout of materials of class C. The rotor is designed as a squrrel rotor with copper bar and casting. The rotor speed is detected by means of a pulse generator. The newer tection motor have no casting(frame). Punched-in holes make up the air duct and transfer the heat losses in complete. Maximim motor rpm is higher due to rotor construction. New is the entry of water-cooled traction motors in urban, However the water cooling design in - unfortunately - not applicable in traction motor.

• 한국군사과학기술학회지
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• 제26권4호
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• pp.361-370
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• 2023

Swarm has recently become a critical component of offensive and defensive systems. Multi-agent reinforcement learning(MARL) empowers swarm systems to handle a wide range of scenarios. However, the main challenge lies in MARL's scalability issue - as the number of agents increases, the performance of the learning decreases. In this study, transfer learning is applied to advanced MARL algorithm to resolve the scalability issue. Validation results show that the training efficiency has significantly improved, reducing computational time by 31 %.