• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.4
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• pp.143-148
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• 2017

Flash Memory which is light and strong external shock as storage of small electronics like smartphone, digital camera, car black box has been widely used. Since the operation speed of the read operation and the write operation are different from each other, and the flash memory has the feature that it is not possible to overwrite, the delete operation is added to solve these problems. Wear-leveling must also be considered, since the number of erase times of the flash memory is limited. Many studies have been conducted on the substitutional algorithms of flash memory based on these characteristics of recent flash memories. So, to solve the problem that has existing buffer replacement algorithm this thesis divide page into 6 groups and when proposed algorithm select victim page, it consider reference page frequency and page recency.

• Fire Science and Engineering
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• v.22 no.4
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• pp.65-69
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• 2008

An accurate knowledge of the flash point is important in developing appropriate preventive and control measures in industrial fire protection. The lower flash points for the n-propanol+formic acid system were measured by Pensky-Martens closed cup apparatus. This binary mixture exhibited MFPB (minimum flash point behavior), which leads to the minimum on the flash point vs composition curve. The Raoult's law and optimization method using Wilson equation were used to predict the lower flash points and were compared with experimental data. The calculated values based on the optimization method were found to be better than those based on the Raoult's law.

• Journal of KIISE:Computer Systems and Theory
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• v.37 no.3
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• pp.161-171
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• 2010

As embedded systems adopt monolithic kernels, NAND flash memory is used for swap space of virtual memory systems. While flash memory has the advantages of low-power consumption, shock-resistance and non-volatility, it requires garbage collections due to its erase-before-write characteristic. The efficiency of garbage collection scheme largely affects the performance of flash memory. This paper proposes a novel garbage collection technique which exploits data redundancy between the main memory and flash memory in flash memory-based virtual memory systems. The proposed scheme takes the locality of data into consideration to minimize the garbage collection overhead. Experimental results demonstrate that the proposed garbage collection scheme improves performance by 37% on average compared to previous schemes.

• The Journal of the Korea Contents Association
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• v.5 no.2
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• pp.7-17
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• 2005

Flash contents for education can embody easily complex interactions with learner by splendid contents of various multimedia and animation. Moreover, they provide high class user interface and have advantages of inducing learner's interest and concentration. However, authoring flash content requires the skill to use the Flash tool, which is too difficult for professor to make the educational Flash contents. In this paper, we proposed the system that professors can make the Flash contents automatically by selecting something necessary and typing texts on the web. Also, the reusability and usability of the implemented system is analyzed in the viewpoint of professor by comparing with conventional method to reuse the Flash contents from various viewpoints.

• 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.

• Journal of the Institute of Convergence Signal Processing
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• v.8 no.3
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• pp.205-210
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• 2007

This paper presents a CMOS TIQ flash A/D converter which operates very fast compared to other types of A/D converters due to its parallel architecture. The output resolution of designed A/D converter is 6-bit. In order to reduce the power consumption and chip area of conventional flash A/D converter, TIQ based flash A/D converter is proposed, which uses the advantage of the structure of CMOS transistors. The length and width of transistors of TIQ were determined with HSPICE simulation. To speed up the ultra-high speed flash A/D converter, the Fat Tree Encoder technique is used. The TIQ A/D converter was designed with full custom method. The chip's maximum power consumption was 38.45mW at 1.8V, and the operating speed of simulation was 2.7 GSPS.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.6
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• pp.125-131
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• 2009

The aim of this study is to quantify the severity of flash food for a study watershed in Korea by estimation of flash food index using flood runoff hydrograph following Bhaskar et. al (2000). As an extension of the previous research, we examine the relation between flash food index and rainfall intensity, rainfall duration, and total runoff, respectively. This study has estimated the flash food index through simulated flood hydrographs to investigate the relative severity of flash flood in an ungauged basin, Megok river basin for 31 flood events.

• 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.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.436-439
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• 2011

본 논문은 클록 보정회로를 가진 1V 2.56-GS/s 6-bit flash analog-to-digital converter (ADC) 제안한다. 제안하는 ADC 구조에서 아날로그 블록은 단일 T/H와 2단의 프리앰프, 그리고 비교기를 사용된다. 2단의 프리앰프와 비교기의 출력에 옵셋의 크기를 줄이기 위하여 저항 평균화 기법을 적용하였다. 디지털 블록은 quasi-gray rom base 구조를 사용한다. 3입력 voting 회로로 flash ADC에서 발생하기 쉬운 bubble error를 제거하였으며, 고속 동작을 위해 단일 클록을 사용하는 TSPC F/F로 구현한다. 제안하는 flash ADC는 클록 듀티 비를 조절할 수 있는 클록 보정회로를 사용한다. 클록 보정 회로는 비교기 클록 듀티 비를 조절하여 리셋 시간과 evaluation 시간의 비율을 최적화함으로 dynamic 특성을 확보한다. 제안한 flash ADC는 1V 90nm의 CMOS 공정에서 설계되었다. Full power bandwidth인 1.2 GHz 입력에 대하여 ADC 성능을 시뮬레이션을 통해 확인하였다. 설계된 flash ADC의 면적과 전력소모는 각각 $800{\times}400\;{\mu}m^2$와 193.02mW 이다.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.1
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• pp.36-45
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• 2002

This paper introduces the design and implementation of a flash memory simulator to emulate a real flash memory. Since this simulator provides exact execution time information and parameter testing functions as well as the type, total capacity, block size, and page size of flash memory, it can be used as a real flash memory as viewed by the operating system. Furthermore, the simulator provides time logging functions of the internal routines of the flash memory management software allowing the monitoring of bottlenecks within the software. Finally, we show the performance measurements of applications under the Linux operating systems on both the simulator and a test board verifying the simulator's use as a replacement for real flash memory.