• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.33 no.8
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• pp.23-31
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• 2004

국내 시스템에어컨 시장은 신도시 형성과 주상복합건물 및 중대형 아파트의 전실공조 필요성이 증대하고 빌딩 리노베이션 등 지속적인 건설시장 성장에 따라 수요가 급격히 증가해 왔으며, 중대형 공조설비를 대체할 차세대 공조시스템으로 시장에서 평가받고 있으며, 상업용 공조시장에서 차지하는 비율도 점차 증가하고 있다. 이런 결과 지난해 3,000∼3,500억 원대의 시장 규모는 올해 4,500∼5,000억 원대로 성장이 예상되면, 매년 30% 이상의 지속적인 시장확대가 예측되며, 도입초기에 주상복합, 아파트, 교단, 병원, 중소형 빌딩 등에 한정되었던 시장은 최근에는 중대형 빌딩용 멀티 에어컨의 수요가 꾸준히 늘어나고 있으며 선진시장인 일본에서 중앙공조 및 멀티에어컨의 장점만을 이용한 혼합 공조시스템이 90년대부터 적용되어져 왔으며, 현재에는 대형오피스 빌딩의 경우에도 공조방식이 시스템에어컨 및 혼합공조가 증가하는 추세이다. (중략)

• 보일러설비
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• no.2 s.157
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• pp.88-99
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• 2007

• Composites Research
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• v.24 no.6
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• pp.25-30
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• 2011

This paper presents an experimental study on the enhancement of electromagnetic shielding (EMI) properties of glass fiber, carbon fiber, and glass-carbon fiber composites by adding layers of multi-walled carbon nanotubes (MWCNTs). In the case of glass-fiber composites, spraying 0.1~0.2 g of MWCNT over a fiber area of $200mm{\times}200mm$ (1.8~3.6 ${\mu}m$ in thickness) resulted in significant improvement in EMI shielding effectiveness (SE). Also, when applying multiple MWCNT layers, it was more effective to place the layers concentrated near the center of the composite rather than spreading them out. On the contrary, inherently conductive carbon fiber and glass-carbon fiber composites did not show appreciable improvement with the addition of MWCNT layers. In order to maximize the effectiveness of carbon nanomaterials as EMI shielding fillers, it is imperative to understand the effect of these materials on various EMI shielding mechanisms and their interactions.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.6
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• pp.65-70
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• 2020

In this paper, to establish a high-efficiency air-conditioning and heating system, we developed a simultaneous air-conditioning and heating system that can do both air-conditioning and heating at the same time. It was applied to hybrid plant plants to enable automation of complex farms. For this purpose, the heat exchanger, which functions as a condenser during heating, was required to function as an evaporator during cooling so that air conditioning and heating could be implemented simultaneously. For experiments, the simultaneous air conditioning system for heating and cooling was produced and applied to the plant factories in the farms so that plants could be grown, stored, and dried. As a result, a single system was able to control the temperature environment of agricultural products with an energy-saving system that simultaneously resolves heating and cooling. Therefore, efficient crop management was possible by implementing an air conditioning system that did not require installing air conditioners and boilers at the same time.