• Journal of the KSME
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• v.17 no.1
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• pp.23-27
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• 1977

태양열을 냉방에 이용하기 위한 시스템은 집열기,열교환기,냉동기 등으로 구성된다. 집열기는 난 방시와 마찬가지로 볼 때 냉난방을 병용하는 집열기를 사용하면 유리하다. 열교환기는 집열기에 서 수집한 열을 냉방기에 전달시키는 기능을 가지는데 용도에 따라 이것을 사용하지 않는 경우도 있다. 냉동기로는 보통 흡수식 냉동기를 사요하나 그외 개방식, 분사식 등의 냉동기도 사용된다. 그러나 분방식 냉동기는 취급은 용이하나 흡수제의 재생조건이 까다로워 높은 습기를 갖는 경우 재생온도가 역시 높아져야 하므로 우리나라의 경우에는 여름철의 습도가 높기 때문에 재생온도가 높아져야 하므로 태양열 냉방에는 부적당하다. 또 분사식 냉동기의 경우 성적계수(Coefficient of Performance) 가 다른 냉동기에 비해 낮고 증기압력이 낮으면 이것이 극히 낮아지기 때문에 태양 열 냉방에 많이 사용하지 않는다. 그래서 태양열 냉방에 있어서 냉동기는 거의 흡수식을 사용하 고 있으며, 여기에서도 주로 흡수식 냉동기를 사용한 냉방에 대하여 논하고져 한다.

• Fire Science and Engineering
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• v.25 no.1
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• pp.57-62
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• 2011

The flash point is one of the most significant combustion properties of flammable liquids in industrial processes when evaluation process safety, In this paper, Cleveland open cup tester is used to measure the flash points for the two binary systems (n-propanol + formic acid and acetic acid + propionic acid). The measured flash points were compared with the values calculated by the Raoult's law and the optimization method using van Laar and Wilson equations. The calculated values based on the optimization method were found to be better than those based on the Raoult's law.

• Proceedings of the CALSEC Conference
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• 1999.07a
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• pp.335-347
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• 1999

o 열린정부/열린국방/열린군수 요구 - 군수품 획득/조달 : 개방/공개경쟁 요구(국민) - 군내 보급/분배 : 백화점식 개방요구(군사용자) - 민ㆍ군간 연계된 회득/군수시스템의 정보화 요구(중략)

• Fire Science and Engineering
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• v.29 no.6
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• pp.45-50
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• 2015

The flash point is one of the most important properties for characterizing the fire and explosion hazard of liquid solutions. In this study, a Tag open-cup apparatus was used to measure the flash points of two flammable binary mixtures, n-decane + n-octanol and acetic acid + n-butanol. The flash point temperature was estimated using the UNIFAC (Universal Functional Activity Coefficient) group contribution model and optimization method. The experimentally derived flash point was also compared with the predicted flash point. The two methods can estimate the flash point fairly well for the n-decane + n-octanol and acetic acid + n-butanol systems.

• Proceedings of the IEEK Conference
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• 2003.07a
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• pp.577-580
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• 2003

최근 차세대통합네트워크(NGN), ALL-IP 망 진화 방향과 함께 동기식과 비동기식 IMT-2000 망의 통합(Convergence) 또는 연동(Harmonization)에 관한 연구가 활발히 이뤄지고 있으며, 이동통신 망의 개방화에 대한 분위기가 점차 무르익어 가고 있다. 이러한 추세에 UMTS, cdma2000, WLAN 과 같은 서로 다른 방식의 무선 액세스 망으로부터 요구되는 무선인터넷 접속 요구를 하나의 통로로 연결하고 수용할 수 있는 모바일 액세스 통합 게이트웨이가 필요하다. 본 논문에서는 차세대 네트워크 발전 방향과 이동통신 망 개방의 흐름에 맞추어 동기식 망과 비동기식 IMT-2000 망에서 동시에 무선인터넷 서비스 접속을 제공하는 통합 게이트웨이 시스템(A-MiDAS)을 개발하기 위한 형상 설계 방법과 시스템 개발 시 고려사항 등에 대해서 기술한다.

• Fire Science and Engineering
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• v.20 no.3 s.63
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• pp.29-34
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• 2006

The flash and fire point are the most important combustible properties used to determine the potential for the fire and explosion hazards of flammable material. The flash point is defined as the lowest temperature at which a flammable liquid gives off sufficient vapor to form an ignitable mixture with air near its surface or within a vessel. The fire point is the temperature of the flammable liquid at which there will be flaming combustion, sustained 5 seconds in response to the pilot flame. In this study, the flash points and fire points were measured to present raw data of the flammable risk assessment for acids, using Pensky-Martens Closed Cup(C.C.) apparatus (ASTM-D93) and Tag Open-cup (O.C.) apparatus(ASTM D 1310-86). The measured fire points were compared with the estimated values based on 1.11 times stoichiometric concentration. The values calculated by the proposed equation were in good agreement with measured values.

• Journal of the Korean Society of Propulsion Engineers
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• v.18 no.3
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• pp.78-83
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• 2014

A special part such as a flow passage opening device is required to prevent the disconnection of fuel transfer in a pressurized fuel tank. To meet this requirement, the device utilizing an acceleration follow-up technique was invented. RecurDyn, a dynamic analysis tool, is introduced in this article to predict the device's performance and to determine parameters affecting it. In the analysis, it is shown that balancing weights can open the passage in accordance with fuel position.

• Journal of the Korean Institute of Gas
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• v.9 no.3 s.28
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• pp.21-26
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• 2005

The flash points and the fire points are one of the most important combustible properties used to determine the potential for the fire and explosion hazards of flammable substances. In this study, the flash points of aromatic hydrocarbons, were measured by using Pensky-Martens Closed Cup apparatus(ASTM-D93) and Tag Open-Cup apparatus(ASTM D 1310-86). Also the fire points of aromatic hydrocarbons, were measured by using Tag Open-Cup apparatus. The measured flash points were in good agreement with reference values. The measured fire points compared with the estimated values based on 1.23 times stoichiometric concentration. The values calculated by the proposed equation were in agreement with measured values.

• Fire Science and Engineering
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• v.23 no.5
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• pp.161-166
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• 2009

The lower flash points for the tert-pentanol + propionic acid and p-xylene + propionic acid systems were measured by Tag open-cup apparatus. The experimental data were compared with the values calculated by the Raoult's law, the van Laar equation and the NRTL equation. The calculated values based on the van Laar and NRTL equations were found to be better than those based on the Raoult's law. It was concluded that the van Laar and NRTL equations were more effective than the Raoult' law at describing the activity coefficients for non-ideal solution such as the tert-pentanol + propionic acid and p-xylene + propionic acid systems. The predictive curve of the flash point prediction model based on the NRTL equation described the experimentally-derived data more effectively than was the case when the prediction model was based upon the van Laar equation.

• RED RIBBON
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• s.40
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• pp.40-41
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• 2001