• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.124-130
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• 2001

The heat transfer and flow measurements were made on a cylindrical pedestal mounted on a flat plate with a turbulent impinging air jet. The heat transfer coefficient distributions on the flat plate were measured using the shroud-transient technique and liquid crystal was used to measure the surface temperature. The jet Reynolds number (Re) is 23,000, the dimensionless nozzle-to-surface distance (L/d) from 2 to 10, the dimensionless pedestal diameter-to-height (H/D) from 0 to 1.5, the dimensionless 2nd pedestal diameter-to-height ($H/D_2$) from 0 to 0.4 and the distance from the stagnation point to 2nd pedestal (p/D). The results show that for H/D = 0.5 to 1.5, the Nusselt number distributions on the plate surface exhibit a maximum between $r/d\;{\cong}\;1.0$ and 1.5. The presence of the pedestal appears to cause the flow separation and reattachment on the plate surface, which results in the maximum heal transfer coefficient. Also, for p/D = 2.5 and $H/D_2$ = 0.3, the local Nusselt number in the region corresponding to $r/d\;{\cong}\;1.1$ was increased up to 50% compared to that for $H/D_2=0$.

• Journal of Mechanical Science and Technology
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• 제20권5호
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• pp.681-691
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• 2006

Nucleate boiling heat transfer for refrigerants, R113, and R113+wt4% ethanol mixture, an azeotropic mixture under electric field was investigated experimentally in a single-tube shell/ tube heat exchanger. A special electrode configuration which provides a more uniform electric field that produces more higher voltage limit against the dielectric breakdown was used in this study. Experimental study has revealed that the electrical charge relaxation time is an important parameter for the boiling heat transfer enhancement under electric field. Up to 1210% enhancement of boiling heat transfer was obtained for R113+wt4% ethanol mixture which has the electrical charge relaxation time of 0.0053 sec whereas only 280% enhancement obtained for R113 which has relaxation time of 0.97 sec. With artificially machined boiling surface, more enhancement in the heat transfer coefficient in the azeotropic mixture was obtained.

• 한국태양에너지학회 논문집
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• 제25권4호
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• pp.101-110
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• 2005

An experimental study of heat transfer of submerged water jet impinging normally on a flat plate is presented. Heat transfer measurements obtained with Reverse cone type nozzle(Rcone) were compared to those obtained with Cone type nozzle(Cone) and Square edged type nozzle(Vert) of the same diameter(D=8mm) for different jet velocities in the range of $3{\sim}7m/s(Re_D=30000{\sim}70000)$ and various nozzle-to target spacings($H/D=2{\sim}10$). The local Nusselt number profiles exhibited a sharp drop for $r/D{\leq}0.5$ and 2nd, 3rd peaks revealed at r/D=2, 3 respectively, followed by a slower decrease there after. The peaks were weakened with increasing the nozzle-to target spacing and decreasing the jet velocity. The stagnation Nusselt number of the Reverse cone type nozzle was larger than those of the other two nozzles for H/D=2. 10, but Cone type nozzle had the highest value for $H/D=4{\sim}8$. Also average Nusselt number of the Reverse cone type nozzle was higher than those of the other two nozzles at $H/D=2{\sim}10$, except for $V_o=7ms$ of H/D=6.

• 유통과학연구
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• 제17권2호
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• pp.53-69
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• 2019

Purpose - National scientific technology R&D investment is exceeding 60 trillion won per year, and the results of patent applications and technology transfers are visually improving. However, despite the improving research results of national R&D, the practical results of technology startups are mediocre. It is now time to expand the construction of the technology commercialization ecosystem, where the expansion of national R&D leads to the results of technology startups. Therefore, this study discussed the measures to increase the competitiveness of technology startups through the factual survey of the companies that benefitted from R&D support programs. Research design, data, and methodology - This study targeted 996 companies that benefitted from the R&D projects of the Technology Transfer Center for National R&D Programs, and deducted itemized issues through the survey replies. Survey questions were prepared to estimate the national R&D results, and the technology recognition path, the purpose of detailed introduction of the technology, investment of the commercialization fund, economic results, and the factors of success and failure were analyzed. Results - As for the recognition rate of technology during the process of corporate technology commercialization through the technology transfer, recognition through project participation showed a high response rate, and diverse implications of technology commercialization were deducted through the analysis of economic results. As for the resolution alternatives, the proliferation of technology commercialization platform that can create excellent technology for the companies in early stages and the measure of expanding the distribution of technology infrastructure were suggested. In this study, public technology commercialization strategy is established, and the innovative marketing strategy is presented. Conclusions - This study reveal that the result of creating scientific technology jobs should be deducted, in order to produce the revolutionary results of job creation by suggesting the success models of technology commercialization based on domestic scientific technology. In particular, even though the support systems for public research results are being diversely suggested, accurate studies on their actual conditions are currently lacking. Therefore, this study suggest realistic political alternatives to assure results in the process of public technology commercialization, by examining the current state of public research results of R&D support institutions and diagnosing the issues.

• 기술혁신학회지
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• 제17권3호
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• pp.604-628
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• 2014

본 연구는 산업기술혁신사업의 성과창출에 미치는 영향을 산학연협력형태를 중심으로 분석하여 산학연협력과 관련된 정책이나 전략 수립에 시사점을 제공하는 것을 연구목적으로 하였다. 이를 위해 산업기술혁신사업 성과활용조사 자료를 이용하여 협력형태별로 가설을 설정하였다. 협력연구가 단독연구에 비해 성과가 높게 나타나는지, 협력연구는 주관기관 유형 및 협력파트너에 따라 성과가 달라지는지를 논문, 특허, 기술이전, 사업화, 신규고용을 대상으로 이항 로지스틱 회귀분석을 이용하여 실증분석하였다. 분석결과 협력연구는 단독연구에 비해 성과가 높게 나타났다. 구체적으로 민간기업이 주관하는 연구과제에서는 비영리기관과 협력할 때 논문, 특허, 신규고용 성과가 증가하는 것으로, 반면 민간기업간 협력연구에서는 논문, 기술이전 등의 성과창출은 감소하는 것으로 나타났다. 비영리기관이 주관하는 연구과제에서 민간기업과 협력할 경우, 특허, 기술이전 등 지식 공유 확산 차원의 성과는 증가하는 것으로 나타났다. 본 연구는 산업기술혁신사업 등 정부연구개발 사업의 연구개발 협력과 관련된 정책 수립에 시사점을 제시할 것으로 판단된다.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2001년도 춘계학술대회 발표논문집
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• pp.290-291
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• 2001

The relationship between velocity, viscosity, diffusion coefficient, mass transfer coefficient and characteristic length and mass transfer data can be correlated by dimensionless relationship in electrolytic process. The performance of dyestuff removal was decreased as the flow rate of electrolyte was increased. It was due to the effect of retention time decreasing was superior to that of turbulent inlet mixing. Sh/Sc$\^$1/3/ vs Re plot for Al flat electrode did not showed the general tendency of the relationship between Sh/Sc$\^$1/3/ and Re. It can be thought that flow rate was not sufficiently high to increase the effect of mixing.

• 한국균학회지
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• 제15권4호
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• pp.250-253
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• 1987

원형질체내에 외래유전물질 도입에 의한 균주 개발의 가능성 검토의 일환으로 사철느타리의 원형질체로부터 핵을 분리하여 느타리의 원형질체내로 전이하여 얻은 결과는 다음과 같았다. 1. 핵전이주는 크게 3가지 type으로 구분되었는데 type 1은 아주 빠른 균사생장과 clamp connection를 형성하지 않으며 CM+benomyl에서 균총분리가 나타남으로서 이질이배체로 사료되었다. type 2는 주된 핵전이주로서 모균주와 비슷하거나 다소 빠른 균사생장과 clamp connection을 지녀 자실체를 형성하였으며 heterokaryon으로서 원형질체 융합주와 유사하였다. 그러고 type 3은 핵 또는 염색체 단편의 전이로 clamp connection를 지니지 않고 아주 느리거나 MM에서 생육이 거의 불가능한 균주였다. 2. 핵전이주 및 모균주를 전기영동법으로 esterase 동위효소 pattern을 조사한 결과 핵전이주는 모균주와 구별되었는데 type 1인 이질이배체는 새로운 band를 나타내었으며, type 2와 type 3은 모균주들을 합한 것으로 보였다.

• 한국추진공학회지
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• 제24권3호
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• pp.59-70
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• 2020

본 논문에서는 기존 적층형 배관의 총 열전달 계수 경험식을 활용할 때 발생하는 한계점을 해결하고자, 외부 총 열전달 계수의 강제 대류 열전달 계수 항을 독립적으로 도출하는 간소화된 모델링을 제안하고, 이를 극저온 환경의 실험 결과로 확인하였다. 액체 산소 냉각 나선형 열교환기가 액체 질소와 열교환하는 실험 장치를 구성하고 열교환기의 열전달량을 계측하여, 외부 총 열전달 계수를 도출하였다. 측정된 외부 총 열전달 계수가 모델링으로 예측 곡선과 일치함을 확인하였다.

• 경영과학
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• 제11권3호
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• pp.169-183
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• 1994

Government provides for special considerations to technology transfer and cooperative R&D between Government-Supported Research Institutes(GSRI) and Private sector. Nevertheless, the results of many cooperative R&D stagnates in the innovation. This paper examines the reasons for the current low level of the effectiveness of cooperative R&D between GSRIs and small & medium firms. Recommendation are made to enhance the effectiveness of cooperative R & D.

• 기술혁신연구
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• 제22권4호
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• pp.1-19
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• 2014

본 연구는 교수의 연구 활동과 성과를 바탕으로 교수의 역량이 대학의 기술이전 성과에 미치는 영향력 분석을 목적으로 한다. 이를 위해서 기술이전 경험이 있는 이공계 분야 교수 80명의 개별 데이터를 수집하여 논문 질적 수준, 특허활동, 정부지원 연구비 규모, 민간 연구비 규모, 임용 전 산업체 경력, 임용 후 경력, 연구팀 규모가 기술이전 성과에 미치는 영향을 분석하였다. 주요 연구 결과로 대학에서 교수의 특허활동, 민간 연구비 규모, 교수 임용 후 경력이 기술이전에 영향을 주는 요인으로 분석되었다.