• 한국식품영양과학회지
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• 제26권3호
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• pp.450-455
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• 1997

Scallop, Patinopecten yessonensis(Jay), cultivated in the cold east coast of Kwangwon region, Korea, is expected to be producted to about 50,000 tones in 2000 year. Freezing is one of the most effective methods applied for soraging seafoods. But, the domestic refrigerator with an automatic defrost system shows the temperature fluctuation during defrosting, thus might result in the deterioration of the frozen foods. In this study, the domestic refrigerator with an automatic defrost system, temperature fluctuation from -18 to -5$\pm$1$^{\circ}C$ and fluctuation intervals from 16 to 20 hr, was used for storing scallop. pH was decreased rapidly after 3 month storage, while the content of amino nitrogen was increased continuously. The TMA content of open state was increased very rapidly on 3 month storage and then increased slowly, whereas that of vinyl package increased slowly. The VBN content was increased almost constantly with no significant differences between storage methods. The TBA content was increased up to 3 month storage with the higher value in open state than vinyl package in the beginning periods of storage, and then decreased very rapidly. The number of total viable cell was increased continuously during storage with higher number in open state than vinyl package. The estimated shelf-lives of frozen scallop with open state and vinyl package stored at -18$^{\circ}C$ in the domestic refrigerator with an automatic defrost system were 3.55 and 3.78 months, respectively.

• 기술혁신학회지
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• 제13권1호
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• pp.99-123
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• 2010

Chesbrough가 개방형 혁신이 기업성과에 미치는 영향을 규명한 이래 개방형 혁신의 다양한 성과와 내용을 다루는 연구들이 활성화되고 있다. 아울러, Hippel은 User Innovation 연구를 통해서 의료 장비와 산업자전거 등과 같은 분야에서는 사용자 혁신이 신제품 혁신으로 연결되어 나타나고 있는 것을 보여 주었다. 후자의 경우는 사용자 기반 개방형 혁신의 한 유형으로 볼 수 있다. 그런데 기업의 개방형 혁신의 정도와 내용을 규명하는 방법은 개별 사례연구 혹은 기업에 대한 설문조사를 통한 직접적이고 상당히 질적인 조사 이외에 활성화된 조사 모델이 개발되어 있지 않다. 본 연구는 기술경영 분석 연구에서 그리고 기업의 경영 컨설팅과 신성장 전략에서 각광을 받고 있는 개방형 혁신 연구 방법 모델에 특허분석을 적용하고자 한다. Chesbrough가 자신의 연구에서 일회적으로 밝힌 바 있는 특허를 통한 기업의 개방형 혁신 분석방법을 보다 체계적인 분석모델의 형태로 제안한다. 아울러, 특허기반 개방형 혁신 분석 모델을 대경지역의 IT의료 및 연료전지 분야에 적용하고, 국내외 자동차 및 모바일 대표 대기업인 삼성 모바일 부문과 노키아, 현대자동차와 도요타에 적용함으로써 특허기반 개방형 혁신 분석 모델의 타당성을 검증한다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.167-168
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• 2010

본 연구는 곡면부재로서의 FRP 패널의 활용 가능성을 검토하고 제작장치의 개선을 통해 인발성형된 곡면패널 시작품을 제작하였다.

• Reproductive and Developmental Biology
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• 제30권4호
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• pp.279-285
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• 2006

Vitrification has been suggested to be an effective method for the cryopreservation of human ES cells. However, the efficiency of vitrification with different vehicles remains a matter of ongoing controversy. The objective of this study was to assess the efficiency of cryopreservation in human ES cells by vitrification using different vehicles. A human ES cell line and a variety of vehicles, including micro-droplet (MD), open-pulled straw (OPS) and electron microscopic grid (EM-grid), were employed in an attempt to assess vitrification efficiency. In order to evaluate the survivability and the undifferentiated state of the post-vitrified human ES cells, we conducted alkaline phosphatase staining and characterization via both RT-PCR and immunofluorescence assays. The survival rates of the post-vitrified human ES cells using MD, OPS and EM-grid were determined to be 61.5%, 66.6% and 53.8%, respectively. There also exist significant differences between slow-freezing and vitrification (p<0.01). However, no significant differences were detected between the vehicle types. Finally, the pluripotency of human ES cells after thawing was verified by teratoma formation. Cryopreservation using vitrification is more effective than slow-freezing, and the efficiency of vehicles proved effective with regard to the preservation of human ES cells.

• ETRI Journal
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• 제26권6호
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• pp.583-588
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• 2004

In this paper we investigate the effect of a shield metal line inserted between adjacent bit lines on the refresh time and noise margin in a planar DRAM cell. The DRAM cell consists of an access transistor, which is biased to 2.5V during operation, and an NMOS capacitor having the capacitance of 10fF per unit cell and a cell size of $3.63{\mu}m^2$. We designed a 1Mb DRAM with an open bit-line structure. It appears that the refresh time is increased from 4.5 ms to 12 ms when the shield metal line is inserted. Also, it appears that no failure occurs when $V_{cc}$ is increased from 2.2 V to 3 V during a bump up test, while it fails at 2.8 V without a shield metal line. Raphael simulation reveals that the coupling noise between adjacent bit lines is reduced to 1/24 when a shield metal line is inserted, while total capacitance per bit line is increased only by 10%.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.75.1-75.1
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• 2010

This research presents a fuel cell simulator for control logic verification and operator training. Nowadays, power industries are focusing on clean energy as a response to new policy. The fuel cell can be the solution for clean energy, but operating technology is not well developed compared to other conventional power plans because of its short history. Therefore we need a simulator to verify the new control strategy and train operators, because the price of a real fuel cell system is too high and mechanically weak to be used for these kind of purposes. To develop the simulator, a 300 KW MCFC(Molten Carbonate Fuel Cell) system was modeled with stack, BOPs(pre-reformer, steam generator, etc) and mechanical components(valves, pipes, pumps, blowers, etc). The process model was integrated to emulated control system and HMI(Human Machine Interface). A static load and open loop tests were conducted for verifying the accuracy of the process model, since it is the most important part in the simulation. After verifying the process model, an automatic load change and start-up tests were conducted to verify the performance of a new control strategy(logic and functional loops).

• 조명전기설비학회논문지
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• 제26권11호
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• pp.104-108
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• 2012

Flexible organic thin film solar cell device with Bulk Hetero-Junction (BHJ) structure was fabricated with blended conjugated polymer of PCDTBT : $PC_{71}BM$ as active layer. Surface of ITO anode for the organic solar cell device was treated with ozone. The organic solar cell device with bare ITO showed short circuit current density ($J_{sc}$) of $8.2mA/cm^2$, open-circuit voltage ($V_{oc}$) of 0.73V, fill factor (FF) of 0.36, and power conversion efficiency (PCE) of 2.16%, respectively. The organic solar cell device with ozone treated ITO anode revealed distinctively improved performance parameters:$J_{sc}$ of $9.8mA/cm^2$, $V_{oc}$ of 0.82V, FF of 0.43, PCE(${\eta}$) of 3.42%.

• BMB Reports
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• 제33권3호
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• pp.263-267
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• 2000

We cloned $hda1^+$ (histone deacetylase 1) of fission yeast Schizosaccharomyces pombe. The hda1 of S. pombe was previously reported to encode for an active histone deacetylase (Rundlett et al., 1996; Olsson et al., 1998). The $hda1^+$ is phylogenetically related to the new open reading frame HOS2 of Saccharomyces cerevisiae and only shows a partial homology to the well-known histone deacetylase subclasses, RPD3 and HDA1. A single hda1 mRNA of 1.8 kb was detected at the same level in actively growing and nitrogen-starved cells. When highly over-expressed in S. pombe from an inducible promoter, $hda1^+$ inhibited cell proliferation and caused defects in morphology and cell division. The increased histone deacetylase activity was detected in hdar over-expressing cells. These results suggest that the Hda1p should function on the regulation of cell division possibly by (Allfrey, 1966) direct deacetylation of cytoskeletal (Wade et al., 1997) and cell division regulatory proteins, (Wolffe, 1997) or by controlling their gene expressions.

• 대한기계학회논문집B
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• 제27권5호
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• pp.635-643
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• 2003

Parametric study for the analysis of performance characteristics of a planar -type solid oxide fuel cell(SOFC) using computational flow analysis is conducted. A planar -type SOFC, which is composed by two gas channels (fuel and ai.) and one set of anode-electrolyte-cathode assembly, is modeled as a two -dimensional isothermal case. Results of computational analysis of flow field including distributions of mass fractions in gas channels are used to the performance analysis of the fuel cell. Flow analysis makes it possible to consider current density distributions along the length of the cell in the process of performance analysis of the SOFC. As results of parametric study, it is found that the mole fraction of fuel at the inlet of fuel channel, operating pressure and temperature are closely related to the performance characteristics of SOFC.

• 마이크로전자및패키징학회지
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• 제10권2호
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• pp.33-37
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• 2003

Si 태양전지의 효율 개선을 위해 textured 표면을 갖는 에피텍셜 베이스 전지(TSEB)를 제작하고 이의 전기광학적 특성을 조사하였다. 제작된 전지는 AM-1 100 mW/$cm^2$ 입사광 아래에서 개방전압이 0.62 V로, 단락전류가 40 mA로, 충실도가 0.7, 전력변환 효율이 16%로 나타났다. 본 연구에서 제안된 전지는 $P^-/P^+$ 에피구조에 의한 광흡수 영역에서 캐리어의 드리프트 이동과 효과적 배면전계의 형성, 그리고 buried contact을 통한 낮은 직렬저항 등으로 인해 고효율 Si 태양전지의 제작에 적합한 구조로 판단된다.