• Journal of the Korea Society of Computer and Information
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• v.19 no.6
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• pp.109-117
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• 2014

A cold storage is a warehouse of a insulated building with cooling installations. It has many different types of cold rooms with temperatures below 0 degrees Celsius, and the sequential workflow such as receiving, picking and packing runs in that rooms. Recently, the cold storages have adopted RFID technology, and consequently, warehouse product management in them are becoming intelligent and network. However, information inconsistency in warehouses caused by physical and logical errors reduces reliability in the RFID cold storage management system and worsens their work efficiency. Therefore, it is necessary to develop an early detection system to identify errors. In this paper, we suggest a supervisory system detecting logical errors on business processes of the RFID cold storage. It is composed of a master supervisor and mobile supervisor. In the master supervisor, the manager can set the constraints conditions and get alerts, and in the mobile supervisor, the workers confirm and deal with these faults directly. The supervisory system improve reliability of the RFID cold storage management system by recognizing a failure to identify physically and logically using these constraint conditions. This paper shows that the supervisory system can reduce the average recovery time to improve reliability by decreasing the time for detecting and analyzing errors in the RFID cold storage management system.

• Journal of the Korean Professional Engineers Association
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• v.32 no.2
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• pp.39-43
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• 1999

• The Science & Technology
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• v.35 no.8 s.399
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• pp.30-31
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• 2002

• Journal of the Korean Professional Engineers Association
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• v.34 no.2
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• pp.23-27
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• 2001

Until 1996, CFC refrigerants haven't been used because it destroyed ozone that affecting In ecosystem. And HCFC will prohibit until 2020. In Europe, they attempt to move up its fulfillment. Until now the change have completed CFC into HFC134a and is considerated HCFC into HFC410A and HFC407C. But HFC41 OA has high condenser temperature and HFC407C is non-azeotropic refrigerant mixture and gliding temperature phenomenon. New refrigerant ell POE, PVE, PAG was also developed.

• JOURNAL OF ELECTRICAL WORLD
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• no.5 s.53
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• pp.77-79
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• 1981

건물의 냉방에서 뺄 수 없는 것은 냉방기이다. 냉방기는 보일러와 같이 인축사고와 연결되는 위험성은 거의 없으나 구조가 복잡하기 때문에 점검 개소가 많아 이를 소홀히 하면 치명적인 사고 유발 우려가 있다. 그러므로 운전에 있어서는 세심한 주의를 기울려야 한다. 도한 기계적으로는 이상이 없으나 자동제어 계통 고장에 의해 냉방기가 시동 안되거나 운전중 정지되는 일이 자주 있다. 이때 우리 전기기술자가 빨리 수거하거나 어떻게라도 운전될 수 있는 상태로 만들어야 한다. 먼저 이런 사고가 발생하지 않도록 해야 하는데 발생한 사고에 대해서는 긴급조치를 하는 것도 전기기술자의 사명이다. 그러므로 꼭 알아 두어야 할 냉동기의 기초 지식과 자동시동 회로를 두 번에 걸쳐 해설 하겠다.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.33 no.7
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• pp.33-37
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• 2004

우리나라의 축산물은 소와 돼지가 주를 이루고 있는데, 이의 도축후 냉각에 있어 특별한 관리가 미흡한 실정이다. 그러나 유럽에서는 축산물 도축 후 냉각시스템은 육류의 품질관리에 가장 중요한 요소로 여겨지고 있다. 특히 도축전후의 냉동냉장 기술은 육질뿐만 아니라 중량의 감소를 최소화 할 수 있는 기술로서 중요한 관리점이 되고 있다. 본 고에서는 과거 우리나라에 일부 소개되었던 유럽의 축산물 냉각시스템의 내용 중 축산물 도축 후 냉각시스템을 중심으로 요약 정리하였다. (중략)

• Proceedings of the Membrane Society of Korea Conference
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• 1998.06a
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• pp.171-221
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• 1998

막분리기술은 이제 분리, 정제만의 단순한 개념이 아니며 고도분리정제와 자원재활용등이 복합적으로 해결되는 효율적 공정으로서 "Zero discharge" 및 "Closed-loop System" 으로서의 개념을 가지고 있다. 이것은 Clean Technology의 개념으로서 Membrane기술의 향후 Vision이라고 할 수 있다. 국내에 적용되고 있는 UF/MF막의 용도는 다음과 같다. -수처리분야, 가정용정수기, 폐수처리분야, 식품/생물공정 분야, 전착도장, 흡수식 냉동기의 LiBr 용액정제, 흡수식 냉동기의 LiBr 용액정제

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.59-60
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• 2000

냉각탑(Cooling Tower)은 가열된 물을 냉각, 재순환시켜 냉각수로 재사용하는 일종의 열교환장치로서, 빌딩, 호텔, 병원, 백화점 및 극장 등과 같은 대형건물의 냉동공조시스템에 필수적으로 사용되는 것은 물론이고, 주물공장, 냉동공장 및 석유화학플랜트 등의 중화학공장과 같은 대형공장에도 중요한 Utility설비 중의 하나이다. 이 냉각탑은 각 구성품의 재질은 주로 FRP와 철구조물로 되어있고, 대기 중에서 물 또는 수증기와 직접 접촉하므로 강한 부식성 환경에 노출되어 있다.(중략)

• Journal of the Korean Society of Mechanical Technology
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• v.13 no.1
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• pp.73-79
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• 2011

In this paper, cycle performance analysis of cascade refrigeration system using alternative FREON refrigerants are presented to offer the basic design data for the operating parameters of the system. The operating parameters considered in this study include subcooled and superheated degree, and evaporating and condensing temperature, temperature difference of cascade heat exchanger in cascade refrigeration system. The COP of cascade refrigeration system increases with the increasing subcooled degree, but there is no significant changes with the increasing superheated degree. The COP of cascade refrigeration system depends on evaporating and condensing temperatures of cascade heat exchanger. Therefore, subcooled degree, evaporating and condensing temperature of cascade heat exchanger using alternative FREON refrigerants have an effect on the COP of this system. In this paper, COP of cascade refrigeration system using R23 for low temperature system and R507A for high temperature system is higher 8 ~ 29 % than using R13 for low temperature system and R22 for high temperature system.

• Journal of Food Hygiene and Safety
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• v.38 no.5
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• pp.373-380
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• 2023

This study surveyed and compared the temperature distribution in domestic refrigerators and freezers used in Korea to determine whether temperature varied according to the location of food storage. We selected 50 people to collect temperature data; among them, 25 measured the temperature of refrigerators, while the remaining measured the temperature of freezers. Consequently, the lowest and highest temperatures measured in domestic refrigerators were found to be -8.2℃ and 15.8℃, respectively, with an average temperature of 3.73℃. The temperature distribution based on internal location was: 5.06±1.69℃ for the door storage compartment, 4.18±1.19℃ for the inside wall surface, and 3.41±1.36℃ for the inner storage box. Significant temperature differences between the top and bottom were only identified at the door storage compartment (P<0.01). Further, the minimum and maximum temperatures measured in the freezer was -30.3℃ and 0.7℃, respectively, with an average temperature of -17.95℃. The temperature distribution based on location was: -17.19±1.68℃ for the door storage compartment, -17.81±1.07℃ for the inside wall surface, and -18.78±1.72℃ for the inside storage box. The results were similar to that of the refrigerator, with the lowest temperature in the inside storage box, and a significant temperature difference between the top and bottom noted only at the door (P<0.01). The maximum temperature difference (between locations) within the refrigerator and freezer was found to be 2.18 and 2.02℃, respectively. In conclusion, the temperature in the entire space was not constant; there were significant deviations at different storage locations. Therefore, public authorities should actively advise customers on the recommended storage locations for each food type. People will benefit from awareness about storage management, including avoiding storage of temperature-sensitive foods in door compartment.