• Journal of the Korean Institute of Gas
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• v.12 no.3
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• pp.50-55
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• 2008

The flash points for the systems, ethlybenzene+n-butanol and ethlybenzene+n-hexanol, were measured by using Tag open-cup tester (ASTM D1310-86). These binary mixtures exhibited MFPB (minimum flash point behavior), which leads to the minimum on the flash point vs composition curve. The experimental data were compared with the values calculated by the Raoult's law, the UNIQUAC equation and the NRTL equation. The calculated values based on the UNIQUAC and NRTL equations were found to be better than those based on the Raoult's law. It was concluded that the UNIQUAC and NRTL equations were more effective than the Raoult' law at describing the activity coefficients for nonideal solution such as the ethlybenzene+n-butanol and ethlybenzene+n-hexanol systems. And 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 UNIQUAC equation.

• Journal of electromagnetic engineering and science
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• v.17 no.4
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• pp.233-237
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• 2017

In this paper, a dual-band high frequency (HF) and ultra-high frequency (UHF) radio-frequency identification (RFID) tag antenna is presented that operates in the 13.56 MHz band as well as in the 920 MHz band. A spiral coil along the edges of the antenna substrate is designed to handle the HF band, and a novel meander open complementary split ring resonator (MOCSRR) dipole antenna is utilized to generate the UHF band. The dual-band antenna is supported by a single-feeding port for mono-chip RFID applications. The antenna is fabricated using an FR4 substrate to verify theoretical and simulation designs, and it has compact dimensions of $80mm{\times}40mm{\times}0.8mm$. The proposed antenna also has an omnidirectional characteristic with a gain of approximately 1 dBi.

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.181-185
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• 2005

The flash point is one of the most important combustible properties used to determine the potential for fire and explosion hazards of industrial material. An accurate knowledge of the flash point is important in developing appropriate preventive and control measures in industrial fire protection. The flash points for the n-butanol+n-propionic acid and n-propanol+n-propionic acid systems were measured by using Tag open-cup apparatus(ASTM D 1310-86). The experimental data were compared with the values calculated by the laws of Raoult and van Laar equation. The calculated values based on the van Laar equation were found to be better than those based on the Raoult's law.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.10C
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• pp.946-954
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• 2009

General RFID system has assumed that the communication channel between reader and back-end database is secure channel. However, the reader can be communicated with the database through insecure channel like the communication channel between the reader and the tag according to application environment. In this paper, we propose a new secure RFID mutual authentication protocol based on open network channel which assumed that all communication channels between the database, the reader and the tag are insecure communication channels. The proposed protocol uses a secure one-way hash function to provide authentication and integrity against all communication messages which exchanged on the open channels. In addition, we designed that the proposed protocol can provide forward secrecy by performing the database and the tag update their old secret key with a new secret key after finished mutual authentication.

• Journal of the Korean Society of Safety
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• v.20 no.2 s.70
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• pp.162-168
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• 2005

The lower flash points for the n-propanol+n-decane flammable mixture were measured by the Tag open-cup apparatus(ASTM D 1310). The experimental results of mixture exhibited the lower flash point than those of pure component in the flash point versus composition curve. The experimental value of the minimum flash point is $27^{\circ}C$ at a mole fraction of n-propanol of 0.71, and the flash point of n-propanol was $28^{\circ}C$. The experimentally obtained data were compared with the values that had been calculated by use of the prediction model, which assumes an ideal solution, and the flash point prediction models based on the van Laar equation were used to estimate the activity coefficients. The predictive curve based on an ideal solution deviated from the experimental data for this system. The experimental results demonstrate a close agreement with the predicted curves, which used the van Laar equation. The average absolute deviation(A.A.D.) from using the van Lau equation is $0.83^{\circ}C$. The methodology proposed here in this paper can thus be applied to incorporate an inherently safer design for chemical processes, such as determining safe storage and handling conditions for flammable solutions.

• Journal of Energy Engineering
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• v.24 no.4
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• pp.18-23
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• 2015

The flash point is used to categorize inflammable liquids according to their relative flammability. The flash point is important for the safe handling, storage, and transportation of inflammable liquids. The flash point temperature of two binary liquid mixtures($CCl_4+o-xylene$ and $CCl_4+p-xylene$) has been measured for the entire concentration range using Tag open cup tester. The flash point temperature was estimated using Raoult's law, UNIQUAC model and empirical equation. The experimentally derived flash point was also compared with the predicted flash point. The empirical equation is able to estimate the flash point fairly well for $CCl_4+o-xylene$ and $CCl_4+p-xylene$ mixture.

• Journal of the Korean Society of Safety
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• v.28 no.1
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• pp.35-39
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• 2013

The flash point is an important indicator of the flammability of a chemical. In this study, the flash points for the n-propanol+n-butanol and n-propanol+acetic acid systems were measured by Tag open-cup apparatus. The experimental data were compared with the values calculated by the Raoult's law and optimization method based on van Laar and UNIQUAC equations. The calculated values by optimization method were found to be better than those based on the Raoult's law.

• 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.

• Fire Science and Engineering
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• v.21 no.2 s.66
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• pp.48-53
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• 2007

The knowledge of the flash point of the mixtures is very important for prevention and protection of fire in the industrial field. The flash points for the water+2-propanol system were measured by using Tag open-cup apparatus(ASTM D1310-86). The experimental data were compared with the values calculated by the Raoult's law, the Van Laar equation and the NRTL(Non Random Two Liquids) 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 Van Laar and NRTL equations were more effective than the Raoult' law at describing the activity coefficients for non-ideal solution such as the water+2-propanol system. And the predictive curve of the flash point prediction model based on the Van Law equation described the experimentally-derived data more effectively than was the case when the prediction model was based upon the NRTL equation.

• 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.