• Fire Science and Engineering
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• v.24 no.3
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• pp.66-71
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• 2010

In order to evaluate the fire and explosion involved and to ensure the safe and optimized operation of chemical processes, it is necessary to know combustion properties. Explosion limit is one of the major combustion properties used to determine the fire and explosion hazards of the flammable substances. In this study, the lower explosion and upper explosion limits of esters were predicted by using the heat of combustion. The values calculated by the proposed equations agreed with literature data within a few percent. From the given results, using the proposed methodology, it is possible to predict the explosion limits of the other ester flammable substances.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.9
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• pp.1444-1451
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• 2001

The evolutionary structural optimization(ESO) method has been under continuous development since 1992. The bidirectional evolutionary structural optimization(BESO) method is made of additive and removal procedure. The BESO method is very useful to search the global optimum and to reduce the computational time. This paper presents the ranked bidirectional evolutionary structural optimization(R-BESO) method which adds elements based on a rank, and the performance indicator which can estimate a fully stressed model. The R-BESO method can obtain the optimum design using less iteration number than iteration number of the BESO.

• Fire Science and Engineering
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• v.26 no.4
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• pp.63-69
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• 2012

Explosion limit is one of the major combustion properties used to determine the fire and explosion hazards of the flammable substances. In this study, the lower explosion limit (LEL) and upper explosion limit (UEL) of organic halogenated hydrocarbons were predicted by using the heat of combustion and chemical stoichiometric coefficients. The calculated explosion limits by the proposed equations agreed with literature data within a few percent. From the given results, using the proposed methodology, it is possible to predict the explosion limits of the other organic halogenated hydrocarbons.

• Journal of the Korean Society of Safety
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• v.8 no.3
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• pp.50-55
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• 1993

A new model for predicting upper flammability limits( UFL ) of paraffinic hydrocarbons is developed, based on statistics and numerical simulation. With the proposed model, UFL have been calculated for 24 compounds, and when compared with experimental data, this model produced average percent error of 2.96%. When compared to established methods published by Spakowski and Zabetakis, this model produced more accurate results.

• Fire Science and Engineering
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• v.10 no.2
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• pp.13-19
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• 1996

An estimation methodology, based on statistics and numerical method, has been developed for estimating the upper explosive limits(UEL) of paraffinic and olefinic hydrocarbon compounds. With proposed method, the UEL has been calculated for 24 paraffinic and 10 olefinic hydrocarbon compounds. The estimated the UEL agree with the experimental values within a few percent. A comparisond with four other methods avaiable in the literature are also presented. It is hoped eventually that this method will permit estimation of the UEL with improved accuracy and broader application for other compounds.

• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.3
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• pp.16-23
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• 2012

This study has been conducted to scrutinize agitation effects of an ultrasonic standing wave on the dynamic behavior of methane/air premixed flame. The propagating flame was caught by high-speed Schlieren images, through which local flame velocities of the moving front were analyzed in unprecedent detail. It is revealed that the propagation velocity agitated by the ultrasonic standing wave is greater than that without agitation at the stoichiometric ratio: the velocity enhancement diminishes as the equivalence ratio approaches upper flammability limit or lower flammability limit. Also, vertical locations of the wave-affected frontal distortions do not vary appreciably, unless the propagating-mode characteristics (pressure amplitude and driving frequency) of ultrasonic standing wave were not changed.

• Journal of Korean Medical classics
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• v.19 no.1 s.32
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• pp.194-201
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• 2006

일반래설(一般來說), 상한소양병포괄소시호탕증(傷寒小陽病包括小柴胡湯證), 시호계지탕증(柴胡桂枝湯證), 대시호탕증(大柴胡湯證), 황금탕증(黃芩湯證), 시호계지건강탕증(柴胡桂枝乾薑湯證), 시호가용골모려탕증(柴胡加龍骨牡蠣湯證). 가시한국대표성적임상의서(可是韓國代表性的臨床醫書)${\ulcorner}$동의보감(東醫寶鑑)${\lrcorner}$, 주요재잡병편중(主要在雜病篇中)${\ulcorner}$한(寒)${\lrcorner}$문적소양형증용약리참천술료소양병(門的少陽形證用藥裏參闡術了少陽病) 종차가이간출(從此可以看出)${\ulcorner}$동의보감(東醫寶鑑)${\lrcorner}$대소양병적인식정도여(對少陽病的認識程度與一般的傷寒體系具有明顯的區別). 필자통과분석(筆者通過分析)${\ulcorner}$동의보감(東醫寶鑑) 잡병편(雜病篇) 한(寒)${\lrcorner}$당중적유관소양형증용약적조문(當中的有關少陽形證用藥的條文), 득출여하결론(得出如下結論): ${\ulcorner}$동의보감(東醫寶鑑)${\lrcorner}$당중(當中), 소양병시이구고(少陽病是以口苦), 인건(咽乾), 목현(目眩), 협만(脇滿), 건구(乾區), 왕래한열등증상위주(往來寒熱等症狀爲主), 발병부위시소양병호발부위태양양명지간화흉협(發病部位是少陽病好發部位太陽陽明之間和胸脇); 기재적주요치방시소시호탕(記載的主要治方是小柴胡湯), 황금탕(黃芩湯), 십조탕등삼개처방(十棗湯等三個處方). 종저일점가이간출(從這一點可以看出)${\ulcorner}$동의보감(東醫寶鑑)${\lrcorner}$불구니어(不拘泥於)${\ulcorner}$상한론(傷寒論)${\lrcorner}$적체계(的體系), 갱가중시실용성(更加重視實用性), 즉이증상위중심료해병정(卽以症狀爲中心了解病情), 심조갱가적합적치법여치방(尋更加適合的治法與治方). 기대금후능유인연구유관십조탕시부가이열입소양병치방화(期待今後能有人硏究有關十棗湯是否可以列入少陽病治方和)${\ulcorner}$동의보감(東醫寶鑑)${\lrcorner}$육경형증용약당중적표본개념(六經形證用藥當中的標本槪念).

• Fire Science and Engineering
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• v.27 no.3
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• pp.47-51
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• 2013

The explosion limit is one of the major combustion properties used to determine the fire and explosion hazards of the flammable substances. The explosion limit of organic acids have been shown to be correlated the heat of combustion and the chemical stoichiometric coefficients. In this study, the lower explosion and upper explosion limits of organic acids were predicted by using the heat of combustion and chemical stoichiometric coefficients. The values calculated by the proposed equations agreed with literature data within a few percent. From the given results, using the proposed methodology, it is possible to predict the explosion limits of the other organic acids.

• Fire Science and Engineering
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• v.23 no.5
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• pp.50-56
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• 2009

Explosion limit and autoignition temperature are the major properties used to determine the fire and explosion hazards of the flammable substances. Explosion limit and autoignition temperature for safe handling of ethylene were investigated. By using the literatures data, the lower and upper explosion limits of ethylene recommended 2.6vol% and 36vol%, respectively. Also autoignition temperatures of ethylene with ignition sources recommended $420^{\circ}C$ at the electrically heated crucible furnace (the whole surface heating) and recommended about $800^{\circ}C$ in the local hot surface. The new equations for predicting the temperature dependence and the pressure dependence of the lower explosion limits for ethylene are proposed. The values calculated by the proposed equations were a good agreement with the literature data.

• Fire Science and Engineering
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• v.28 no.2
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• pp.64-68
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• 2014

For the safe handling of cyclohexanol, this study was investigated the explosion limits of cyclohexanol in the reference data. The flash points and auto-ignition temperatures (AITs) by ignition delay time were experimented. The lower flash points of cyclohexanol by using closed-cup tester were experimented in$60^{\circ}C{\sim}64^{\circ}C$. The lower flash points of cyclohexanol by using open cup tester were experimented in $66^{\circ}C{\sim}68^{\circ}C$. This study measured relationship between the AITs and the ignition delay times by using ASTM E659 tester for cyclohexanol. The AIT of cyclohexanol was experimented as $297^{\circ}C$. The lower explosion limit (LEL) and the upper explosion limit UEL) by the measured the lower flash point and the upper flash point of cyclohexanol were calculated as 0.95 Vol% and 10.7 Vol%, respectively.