• Journal of the Korean Institute of Gas
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• v.19 no.3
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• pp.18-24
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• 2015

The flash point is one of the most important indicators of the flammabiliy of liquid solutions. The flash point is the lowest temperature at which there is enough concentration of flammable vapor to form an ignitable mixture with air. In this study the flash points of binary flammable solutions, 2-propanol+propionic acid and n-hexanol+formic acid systems, were measured using Seta flash closed cup tester. Particularly n-hexanol+formic acid system exhibited minimum flash point behavior. The measured values were compared with the calculated values using Raoult's law and optimization method. The calculated data by optimization method described the measured values more effectively than those calculated by Raoult's law.

• Journal of the Korean Institute of Gas
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• v.20 no.6
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• pp.31-36
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• 2016

The flash point is one of the most important indicators of the flammability of liquid solutions. The flash point is the lowest temperature at which there is enough concentration of flammable vapor to form an ignitable mixture with air. In this study the flash points of ternary liquid solutions, n-nonane+n-decane+n-dodecane system, were measured using Seta flash closed cup tester. The measured values were compared with the calculated values using Raoult's law and empirical equation. The calculated data by empirical equation described the measured values more effectively than those calculated by Raoult's law.

• Journal of the Korean Institute of Gas
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• v.18 no.5
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• pp.60-65
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• 2014

The flash point is the major physical property used to characterize the fire hazard of flammable liquid solutions. In the present study, the main focus is on measuring and estimating the flash points for binary flammable mixture. The flash points for n-propanol+propionic acid were measured by Seta flash closed cup apparatus. The experimental data were correlated with the van Laar and NRTL equations through the optimization method. The results estimated by these correlations were compared with the values calculated by the method based on Raoult's law. The optimization method were found to be better than the method based on the Raoult's law.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.1039-1043
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• 1996

In the firing operation, muzzle jumping phenomenon was investigated, and a method of reducing muzzle jump was suggested. The muzzle jumping force was determined from the torque acting on the rifle due to a recoil force. For the purpose of reducing a muzzle jump, the gas flowing through the M16A1 flash suppressor was considered. A flash suppressor, improved in reducing a muzzle imp, was modeled and tested. The experiment shows that muzzle jump has quantitative relation to shape of a flash suppressor, and can be reduced by the improved modeling of a flash suppressor.

• Journal of the Korean Institute of Gas
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• v.24 no.6
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• pp.11-17
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• 2020

In order to guarantee safe storage and transportation of a flammable liquid solution, it is very important to know its flash point information. In this paper, flash points of n-octane+n-nonane system and n-nonane+n-decane system were measured by Seta flash apparatus and an empirical equation is proposed for the accurate estimation of flash point. Empirical equation is used to predict flash point of n-octane+n-nonane system and n-nonane+n-decane system, which were also compared to Unifac-based model. Absolute average errors of flash point data predicted by Unifac-based model are 0.7℃ and 0.6℃ for n-octane+n-nonane system and n-nonane+n-decane system, respectively. Absolute average errors of flash point data predicted by empirical equation are 0.2℃ and 0.4℃ for n-octane+n-nonane system and n-nonane+n-decane system, respectively. In conclusion, empirical equation proposed in this paper, presented the most satisfactory.

• 한국가스학회:학술대회논문집
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• 2003.05a
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• pp.207-212
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• 2003

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.5
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• pp.283-288
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• 2016

A non-lethal weapon is a device that can subdue targets without causing death or mortal wounds. A high-intensity flash generator can negate electro-optical sensors and cause temporal flash blindness with a high intensity of light. In this study, we derive the design parameters of an explosive-driven high-intensity flash generator that uses the interaction of plasma caused by the detonation of explosives with surrounding inert gas. To determine the design parameters of the flash generator, we analyze test results measured using optical sensors. The experimental results show that the light intensity of xenon gas is about four times higher than that of air. In addition, the intensity increases with the weight of the explosive, and the inert gas cross-sectional area encountered a shock wave in the airframe. The light intensity caused by a double-initiation generator is about two times higher than that of the single-initiation generator.

• Journal of the Korean Institute of Gas
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• v.11 no.3
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• pp.13-18
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• 2007

The multivariate statistical analysis, using the multiple linear regression(MLR), have been applied to analyze and predict the flash points of binary systems. Prediction for the flash points of flammable substances is important for the examination of the fire and explosion hazards in the chemical process design. In this paper, the flash points are predicted by MLR based on the physical properties of pure substances and the experimental flash points data. The results of regression and prediction by MLR are compared with the values calculated by Raoult's law and Van Laar equation.

• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.2
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• pp.146-151
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• 2009

It is known that muzzle flash can be generated by the reaction between the oxygen in the air and unburned gunpowder contained in the propellant gas if a barrel is not long enough to burn gunpowder fully inside of the barrel. A hugh muzzle flash, which is a characteristic of small arms with short barrel length, disturbs a shooter in aiming at the target at night by making the shooter blind for a while and endangers the shooter's life by revealing firing position to enemies. In addition, the heat of muzzle flash can deteriorate the performance of thermal sights, which are attached to small arms for effective night combat. In this paper, flash suppressors of different shapes were designed for a newly developed 5.56mm caliber rifle with short barrel length and the performance of each flash suppressor to reduce the muzzle flash was compared by on-site test firing. Through the test firing, a highly efficient design of flash suppressor for reducing the muzzle flash was identified. The result of the paper can be referred when designing flash suppressors for small arms with short barrel length.

• Journal of the Korean Institute of Gas
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• v.23 no.3
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• pp.40-45
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• 2019

Flash point is the important flammability indicator characterizing the risk of fire and explosion of flammable liquid mixture. In this study, flash points of water+formic acid and water+acrylic acid were measured by Seta flash apparatus. The flash points estimated by the methods based on empirical equation and Raoult's law were compared with experimental flash points. Absolute average errors of the results estimated by Raoult's law are $10.7^{\circ}C$ and $4.8^{\circ}C$ for water+formic acid and water+acrylic acid, respectively. Absolute average errors of the results estimated by empirical equation are $1.0^{\circ}C$ and $0.5^{\circ}C$ for water+formic acid and water+acrylic acid, respectively. In conclusion, the estimated values by empirical equation simulated the measured values better than those calculated by Raoult's law.