• The Korean Journal of Malacology
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• v.29 no.3
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• pp.251-258
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• 2013

This study aims to find out a suitable cryoprotective agent (CPA) for cryopreservation and its optimum concentration in order to conduct planned artificial seed production of Pacific oyster, Crassostrea gigas and to preserve superior sperm. For this, we tried to understand toxicity and the effect of cryopreservation by CPA type and concentrations first and then looked into cell damage of the sperm after thawing. Toxicity analysis on the sperm of Pacific oyster according to different CPA and immersion time shows that dimethyl sulfoxide (DMSO) comes first when it comes to survival rate and mobility followed by ethylene glycol (EG), glycerol and methanol. To identify the optimum CPA and its level, filtered seawater was used as a diluent before cryopreservation for 30 days. As a result, cryopreserved sperm of Pacific oyster with 15% of DMSO showed the highest survival rate and activation. Also, we observed the cryopreserved and thawed sperm with Scanning electron micrographs by CPAs and concentrations. Consequently, DSMO showed the lowest cell damage followed by EG, methanol, glycerol and the level was 15, 20, 10, 5% respectively. In a nutshell, it is proven that the optimum CPA and its level is 15% of DMSO.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.6
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• pp.92-99
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• 2005

We are interaction refrigeration warehouse cold water pump system and photovoltaic generation system. At this time, a target pressure is able to control in spite of change of the pressure according to pump head and rate of flow of pump. Also, we carry out the vector control of BLDC motor with the maximum torque operation and a high reliability from territory of each operation speed. Therefore, in this paper, we conclude energy saving technique of refrigeration warehouse cold water pump system.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.4
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• pp.137-144
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• 2016

Commercial buildings account for a significant proportion of the total building energy use in Korea, and cooling energy, in turn, accounts for the largest proportion of total energy consumption in commercial buildings. Under this circumstance, chiller staging is considered to be a reasonable and practical solution for cooling energy saving. In this study, the part-load ratio and the operating characteristics of a vapor compression chiller were analysed within an office building. In addition, energy consumption among different chiller staging schemes was comparatively analysed. As a result, significant proportions of total operating hours, cooling load and energy consumption turned out to be in the part load ratio range from 0% through 50%, and thus energy consumption was significantly affected by the chiller COP at low part-load conditions, indicating that the chiller operation at the part-load is an important factor in commercial buildings. In addition, utilizing a sequential chiller staging scheme can reduce the annual cooling energy usage by more than 10.3% compared to operating a single chiller.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.10a
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• pp.172-176
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• 2005

본 연구의 목적은 냉동 저장 시 돈육의 부위, 포장방법 및 저장기간이 지방산패에 미치는 영향을 측정하기 위하여 실시하였다. pH는 고지방인 삼겹이 저지방인 등심보다 높은 값을 나타냈다(P<0.05). TBARS 값은 저장기간과 포장방법에 의한 차이는 나타나지 않았으나(P>0.05) 저장 후반부로 갈수록 고지방인 삼겹이 저지방인 등심보다 높게 나타났다. (P<0.05). 유리지방산가는 TBARS 값과 반대로 오히려 저지방인 등심이 고지방인 삼겹보다 높게 나타났다(P<0.05). 과산화물가는 저장기간이 증가함에 따라 값이 증가하였다(P<0.05). 미생물 변화는 저장기간, 포장방법, 지방함량에 따른 뚜렷한 차이는 나타나지 않았다. (P>0.05). 추출된 휘발성 화합물들은 저장기간에 따른 변화가 미미하였고 포장방법에 따른 효과는 나타나지 않았으나 (P>0.05) 탄소수 10개 미만인 2,4-dimethyl-1-heptene, hexanal 그리고 4-methyl-2-hexanone은 저지방인 등심보다 고지방인 삼겹에서 더 많이 검출되었으며, 이와는 반대로 탄소수 10개 이상인 고분자 화합물들은 고지방인 삼겹보다는 오히려 저지방인 등심에서 많이 검출되었다(P< 0.05). 상관관계를 조사한 결과 삼겹에서 유리지방산가와 4-methyl-2-hexanone, 등심에서 유리지방산가와 9-octadecenal을 제외하고는 별다른 유의성이 존재하지 않았다. 이러한 결과는 식육의 냉동보관은 식육내 존재하는 지방의 산화와 미생물 성장을 억제하여 미생물, 효소 그리고 자동산화로 인해 발생되는 여러 가지 2차 생성물의 생성을 저해하는 것으로 판단된다.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.594-599
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• 1988

Methods by which liquid egg could be stored in liquid state at frozen storage temperature$(-15^{\circ}C)$ with selected cryoprotectants and enzyme treatment were investiated, and quality changes in samples during storage were examined. The concentration of cryoprotectants (45% fructose and 55% glucose) to be added to egg yolk and whole egg to store them at $-15^{\circ}C$ in unfrozen state were 45.2% and 70.3%, respectively. Changes in consistency, precipitation of protein and microstructure of egg samples during storage indicated that adding cryoprotectants to liquid egg could effectively inhibit development of gelation during storage at $-15^{\circ}C$. Treating liquid egg with 0.15% papain could inhibit gelation during storage to some extent.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.60 no.2
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• pp.194-206
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• 2024

This study focuses on analyzing the energy-saving effects of the recirculation aquaculture system using seawater source heat pumps and solar power generation. Based on the thermal load analysis conducted using the transient system simulation tool, the annual energy consumption of the recirculation aquaculture system was analyzed and the energy-saving effects of utilizing the photovoltaic system was evaluated. When analyzing the heat load, the sea areas where the fish farms are located, the type of breeding tank, and the circulation rate of breeding water were taken into consideration. In addition, a method for determining the appropriate capacity for each operation time was examined when applying the energy storage system instead of the existing diesel generator as an emergency power, which is required to maintain the water temperature of breeding water during power outage. The results suggest that, among the four seas considered, Jeju should be estimated to achieve the highest energy-saving performance using the solar power generation, with approximately 45% energy savings.

• 월간 기계설비
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• s.40
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• pp.50-56
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• 1993

장인상 대한주택공사 기계설치 1처 과정은 모든 건축물의 고층화가 가속화되고 있는 가운데 배관설비 규정의 내용과 제정 배경을 살펴보고, 규정 적용상의 효과와 문제점을 검토함으로써 공동주택 배관시스템 개발의 방향을 제시한 원고를 (사)공기조화$\cdot$냉동 공학회의 기술자료(제22권 제3호)에 게재, 본지에서는 그 내용중 일부를 요약 발췌 게재한 것임을 밝혀드립니다.

• the MEAT Journal
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• s.26 fall
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• pp.80-95
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• 2002

우리 협회에서는 식육가공품(식육,육가공품,냉동식품)에 대한 소비자 인식계몽과 업계 및 회원사의 주요 PR 사항을 기사화하여 식육가공품에 대한 소비자들의 호응도를 높이기 위해 다양한 형태의 대언론 활동을 강화하고 있습니다. 지난 9월까지 협회의 도움말로 주요 언론매체에 기사화된 내용을 수록합니다. 더욱 효과적인 홍보효과를 얻을 수 있도록 회원사 여러분의 적극적인 참여를 기대합니다.

• Electrical & Electronic Materials
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• v.6 no.5
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• pp.417-427
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• 1993

액체질소하에서의 물리적인 현상 및 실험결과를 통하여 캐리어 냉동현상, 좁은 폭 및 숏트 채널효과를 포함한 문턱전압 모델, Surface Roughness Scattering 및 Ioniaed Impurity Scattering을 포함한 이동도 모델과 적합한 기판 전류모델이 제안되었으며 이 모델들은 모의실험 프로그램인 BSIM과 SPICE에 이식되었다. 제작된 링 오실레이터와 리플 가산기에 적용한 결과 측정한 데이타와 잘 부합되었다.

• Proceedings of the Korean Aquaculture Society Conference
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• 2004.05a
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• pp.302-303
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• 2004