• Journal of the Korean Society of Safety
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• v.12 no.3
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• pp.114-119
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• 1997

The lower flash points and upper flash points of 2-propanol and toluene mixtures were determined by air-blowing method instead of Tag-closed flash point tester. The relations between the flash points and the composition of the mixtures are as follows, $T_{F.L}=4.3182+6.0909X_1$ $T_{F.U}=39.3636-2.9091X_1$ As results, the experimental data and the estimated values from the relations are considerably agreed, and we could plotted the relative diagram between flash points and the explosive range.

• Journal of the Korean Society of Safety
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• v.30 no.4
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• pp.86-91
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• 2015

The flash point is used to categorize inflammable liquids according to their relative flammability. Such a categorization is important for the safe handling, storage, and transportation of inflammable liquids. The flash point temperature of two binary liquid mixtures(n-octane+n-decane and n-octane+n-dodecane) has been measured for the entire concentration range using Seta-flash closed cup tester based on the ASTM D3278 method. The closed cup flash point temperature was estimated using the UNIFAC(Universal Functional Activity Coefficient) group contribution model. The experimentally derived flash point was also compared with the predicted flash point from the UNIFAC model. The UNIFAC model is able to estimate the flash point fairly well for n-octane+n-decane mixture and n-octane+n-dodecane mixture.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.362-362
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• 2020

Flash flood is a dangerous weather phenomenon, affecting humans and the economy. The identification, forecast of the changing trend and its characteristics are increasingly concerned. In the world, there have many methods for determining the characteristics of flash floods, in which flash flood guidance (FFG) is a fast, effective and widely used method. The main source of flash floods is short-term rainfall. In this study, we used the data of cross-sectional measurement at the tributaries and the hourly rain data from the automatic rainfall measurement stations in the Geum river basin. Besides, we use a combination of the flash flood guidance and the best fit distribution function to estimate the repeatability of flash floods for head-water catchments in Geum river basin. In which, FFG determines the threshold of rainfall for flash floods. The study has determined the best hourly rainfall distribution function for the Geum river basin and estimated the maximum rainfall of 1hr according to the return periods.

• International Journal of Safety
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• v.10 no.1
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• pp.5-9
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• 2011

Two popular activity coefficient models, Wilson and NRTL equations have been used to correlate the published flash point data on the n-propanol + propionic acid and n-butanol + propionic acid systems through the optimization method. The results of these correlation were compared with the results calculated by Raoult's law. The optimization method were found to be better than those based on the Raoult's law. The optimization method based on the Wilson equation described the published data more effectively than was the case when the optimization method was based upon the NRTL equation.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.5
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• pp.372-377
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• 2003

To realize a high integrated flash memory utilizing SONOS memory devices, the NOR type ITC(one Transistor Cell) SONOS flash arrays are fabricated and characterized. This SONOS flash arrays with the common source lines are designed and fabricated by conventional 0.35$\mu\textrm{m}$ CMOS process. The thickness of ONO for memory cells is tunnel oxide of 34${\AA}$, nitride of 73${\AA}$ and blocking oxide of 34${\AA}$ . To investigate operating characteristics, CHEI(Channel Hot Electron Injection) method and bit line method are selected as the program and 4he erase operation, respectively. The disturbance characteristics ,according to the program/erase/read cycling are also examined. The degradation characteristics are investigated and then the reliability of SONOS flash memory is guaranteed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.10a
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• pp.58-61
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• 2010

In this paper, we research the method for HDD I/O Performance improvement by Filter Driver &NAND FLASH Memory. We analyze the effect of the operation of the Device Driver & NAND FLASH Memory and propose the method for the HDD I/O Performance improvement.

• IEMEK Journal of Embedded Systems and Applications
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• v.18 no.1
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• pp.25-30
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• 2023

We propose a method to update DSP (Digital Signal Processor) firmware using USB (Universal Serial Bus) flash drives. The DSP automatically detects USB drives based on an interrupt when the USB drive is inserted into the USB port. The new firmware binary file is found in the mounted USB drive, and the destination address of DSP flash memory is identified for the firmware update writing by investigating the firmware file header. After the new firmware is written to the DSP flash memory, the DSP is reset and rebooted with the newly updated firmware. By employing TI's TMS320F28379D control card with USB ports, we conduct experiments and verify the normal operation of the implemented method.

• 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.

• Journal of the Korean Society of Safety
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• v.34 no.1
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• pp.34-39
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• 2019

Flash point is the important indicator to determine fire and explosion hazards of liquid solutions. In this study, flash points of n-propanol+n-hexanol and n-butanol+n-hexanol systems were obtained by Seta flash tester. The methods based on UNIFAC equation and multiple regression analysis were used to calculate flash point. The calculated flash point was compared with the experimental flash point. Absolute average errors of flash points calculated by UNIFAC equation are $2.9^{\circ}C$ and $0.6^{\circ}C$ for n-propanol+n-hexanol and n-butanol+n-hexanol, respectively. Absolute average errors of flash points calculated by multiple regression analysis are $0.5^{\circ}C$ and $0.2^{\circ}C$ for n-propanol+ n-hexanol and n-butanol+n-hexanol, respectively. As can be seen from AAE, the values calculated by multiple regression analysis are noticed to be better than the values by the method based on UNIFAC eauation.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.3
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• pp.151-156
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• 2011

Previously most of flood prevention efforts have been made for relatively large watersheds near to channel flow. However, as economical development and the expansion of leisure areas to mountainous region, human casualty by flash flood occurs frequently, requiring additional prevention activity. Therefore, to reduce the damage of human lives and property by flash flood, we develop an assessment method for flash flood occurrence for mountainous areas considering various factors involving it. PROMETHEE(Preference Ranking Organization METHod for Enrichment Evaluations) which is one of the MCDM(Multi-Criteria Decision Making) was adopted to assess the contribution of each factor to the risk of the flash flood in the mountainous area. The main evaluation criteria are classified into three categories, namely, the regional and rainfall characteristics, and geographical features. Also, the Entropy method is used to determine the weight of each evaluation criteria without survey. The suggested method based on PROMETHEE with Entropy method is applied to BongHwa region to verify its applicability. After applied, the method successfully assesses the relative risk of flash flood occurrence of each sub region in the BongHwa region. Out of the seventeen sub-regions, five, seven and five of them are evaluated as high-risk, medium-risk, and low-risk, respectively. To verify the results, we searched the historical data of flash flood and the flash flood had occurred in one of high-risk sub-regions at 2008.