• Proceedings of the Korean Information Science Society Conference
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• 2012.06a
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• pp.311-312
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• 2012

도시 컴퓨팅에서의 파일 시스템은 하나의 메타 데이터 서버와 여러 개의 데이터 저장 서버로 구성되어 있다. 이 데이터 저장 서버의 자료구조를 사용자의 두 가지 질의에 맞게 구성함으로써 미리읽기의 성능을 향상시킨다. 또한 데이터의 손실을 방지하기 위해 복사본을 만들 때, 두 가지의 형태로 바꿔 저장함으로써 데이터의 손실을 막고 여러 질의에 대응하여 좋은 성능을 낼 수 있다.

• Proceedings of the Korea Database Society Conference
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• 1994.09a
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• pp.213-234
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• 1994

고도 정보화 사회로 발전해 감에 따라 사회 전반에서 발생하는 정보들을 컴퓨터에 저장하여 관리하는 정보 관리 시스템들이 많이 개발되고 있다. 특히 컴퓨터 기술의 발달과 통신의 발달은 서로 떨어져 있는 정보 시스템끼리의 정보 교환을 보다 효율적으로 할 수 있게 되어 시스템 통합 환경으로 선도하고 있다. 이에 본 논문에서는 시스템 통합 환경에서 공유 데이타 저장소를 기반으로 하여 지역 데이타베이스를 구축할 수 있는 데이타 모델인 ESR 데이타 모델을 제안하고, 그에 따른 데이타 모델링 방법론을 제안하였다. 또한 공유데이타 저장소를 기반으로 하여 ESR 데이타 모델링을 통한 데이터베이스를 설계할 수 있는 지원도구를 설계하였다.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1998.05a
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• pp.131-136
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• 1998

초전도에너지저장(SMES)장치는 초전도 코일의 무저항성에 의한 고 효율성, 빠른 응답속도 등의 장점으로 미래의 전력수요공급측면에서 궁극적인 전력저장장치로서의 역할이 확실시되며 이러한 맥락에서 SMES장치의 연구개발 필요성이 강조된다.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2011.05a
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• pp.69-70
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• 2011

본 논문은 사용후핵연료의 장기저장으로 인하여 발생할 처분지연에 대한 경제적 효과를 분석하였다. 분석 결과, 사용후핵연료 장기저장을 통하여 고준위방사성폐기물의 지하처분장 건설을 190년 지연시킬 경우, 2040년에 처분장을 건설할 경우와 비교하여 약 1/3의 비용이 소요되는 것으로 계산되었다. 이러한 결과는 경수로핵연료 2만톤과 CAMDU 1만6천톤을 처분하는 것을 가정하여 순전히 경제적인 관점에서 산출된 결과이다.

• Food Science and Preservation
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• v.11 no.4
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• pp.448-454
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• 2004

This study was conducted to analyze the cooling and the quality characteristics of milled rice stored in the forced air-blast type using thermo -electric semiconductor and in the still-air type chambers using refrigeration system with refrigerant(R-22). Cooling rates of milled rice in the forced air-blast type and in the still-air type chambers were $0.30\;^{\circ}C/hour$ and $0.21\;^{\circ}C/hour$, respectively. And the temperatures of cooling air and of milled rice at different positions in the forced air-blast type chamber showed severer change than those in the still-air type chamber. During storage of milled rice in the forced air-blast type and still-air type chambers for 14 weeks, there was no significant difference in the quality characteristics, such as b value and fat acidity of milled rice, and overall sensory quality of cooked rice. But the quality characteristics of milled rice stored in room temperature chamber($25^{\circ}C$) as control decreased very rapidly compare to those stored in the cooling chambers. In aspect of fat acidity of milled rice, 6 weeks was the limitation for the safe storage in room temperature.

• Food Science and Preservation
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• v.24 no.6
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• pp.857-864
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• 2017

To establish good storage practices for hulled barley against mycotoxin contamination, we measured occurrence of fungi and mycotoxin in hulled barley grains under various storage conditions. Hulled barley grains collected from two places were stored in five different warehouses: 1) two without temperature control, 2) one with temperature controlled at $12^{\circ}C$, 3) a chamber set at $15^{\circ}C/65%$ relative humidity, and 4) one seed storage set at $10^{\circ}C$. The samples were stored for six month with temperature and relative humidity monitored regularly. Every stored samples were retrieved after 0, 1, 3, and 6 month to investigate fungal and mycotoxin contamination. From the stored grains, Fusarium, Epicoccum, Alternaria, and Drechslera spp. were frequently detected. In the warehouses without temperature control, Fusarium and Alternaria spp. constantly decreased, whereas Drechslera spp. increased along with storage period. In the other warehouses with temperature controlled, Fusarium spp. decreased slowly and more than 2.5 log CFU/g of Fusarium spp. were detected after 6 month storage. The level of nivalenol was maintained during 0-3 month but increased after 6 month storage. There was no difference in the nivalenol levels between the warehouses. Therefore reducing storage period less than 6 months could be more effective to control nivalenol contamination in hulled barley grains.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.1
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• pp.95-103
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• 1997

This experiment was carried out to obtain the basic information necessary to establish suitable postharvest handling techniques and to keep high quality of the sweet(Danok 2), supersweet(Cooktail 86) and waxy(Chalok 1) corn which are mainly consumed as vegetable in Korea. Vegetable corns were cooled with ice fragments in the insulation box immediately after harvest and stored in low temperature warehouse at 0 to 2$^{\circ}C$. During the 15 days short-term storage, changes of chemical components were compared with those of uncooled corns. The losses of moisture in kernels were as high as 7.4 to 24.4％ in uncooled corns while those of ice cooled corns increased 0.4 to 0.5％ of their weight. The ratio of pericarp and alcohol insoluble solid(AIS) content increased as the storage days prolonged in all treatments but increasing rates were much higher in uncooled samples. On the other hand, the total sugar loss during storage was the least in supersweet corn when they were cooled with ice fragments in insulation box. After 5 days storage, the ice cooled samples showed the highest free amino acid contents compare to those of uncooled and stored at room temperature (25 to 3$0^{\circ}C$) or low temperature warehouse, and ${\gamma}$-aminobutylic acid (GABA) which was known as a fuctional amino acid was detected in all three kinds of vegetable corns.

• Journal of Internet Computing and Services
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• v.9 no.1
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• pp.43-54
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• 2008

In this paper, we implement an automatic entity information management system for smart refrigerator using RFID technology in which objects containing electronic tags are automatically identified using radio wave. Unlike current "smart" refrigerators, the system presented in this paper implements smart tag information acquisition mechanism and real-time information management system to provide various information on entities in refrigerators to local and remote users. As the first step, this paper analyzes the requirements for smart refrigerator system based on the RFID and suggests design considerations. Based on the analysis, we propose and implement an efficient tag location tracking method based on antenna transfer method and an intelligent tag information management system based on embedded database and web server. We also provide a wide range of experimental results on the number of tags identified at a time and the tag recognition ratio according to the RFID antenna transfer speed and the angle between tag reader and tags.

• Tunnel and Underground Space
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• v.22 no.1
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• pp.1-11
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• 2012

Thermal energy storage is defined as the temporary storage of thermal energy at high or low temperatures for later use in need. The energy storage can reduce the time or rate mismatch between energy supply and demand, and thus it plays an important role in conserving energy and improving the efficiency of energy utilization, especially for renewable energy sources which provide energy intermittently. Underground thermal energy storage (UTES) can have additional advantages in energy efficiency thanks to low thermal conductivity and high heat capacity of surrounding rock mass. In this paper, we introduced the technologies of underground thermal energy storage and rock caverns for hot water storage in Sweden.

• Journal of Korea Society of Industrial Information Systems
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• v.27 no.4
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• pp.29-36
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• 2022

Existing IoT sensor nodes operate by receiving energy from a battery. But due to the characteristics of sensor nodes that are widely distributed for collecting various information, there is a disadvantage that the battery needs to be periodically replaced. In order to overcome this disadvantage, energy can be harvested from sunlight or high-temperature steam through an energy harvesting system. However, since the harvested power is quite limited, it is difficult to use applications that require instantaneous high power such as communication. We propose the design of the high-power energy harvesting system where a switch control unit compensates for the limited harvested energy with the energy storage device such as a capacitor. To verify the proposed system, an energy harvesting system based on sunlight was implemented, and we confirmed the maximum supply power to the application and the maximum supply time according to capacity of the energy storage device.