• Journal of the Korean Institute of Gas
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• v.9 no.3 s.28
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• pp.21-26
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• 2005

The flash points and the fire points are one of the most important combustible properties used to determine the potential for the fire and explosion hazards of flammable substances. In this study, the flash points of aromatic hydrocarbons, were measured by using Pensky-Martens Closed Cup apparatus(ASTM-D93) and Tag Open-Cup apparatus(ASTM D 1310-86). Also the fire points of aromatic hydrocarbons, were measured by using Tag Open-Cup apparatus. The measured flash points were in good agreement with reference values. The measured fire points compared with the estimated values based on 1.23 times stoichiometric concentration. The values calculated by the proposed equation were in agreement with measured values.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.36 no.1
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• pp.23-28
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• 2023

This paper demonstrates a novel NAND flash memory structure and annealing configuration including through-silicon via (TSV) inside the silicon substrate to improve annealing efficiency using an electro-thermal annealing (ETA) technique. Compared with the conventional ETA which utilizes WL-to-WL current flow, the proposed annealing method has a higher annealing temperature as well as more uniform heat distribution, because of thermal isolation on the silicon substrate. In addition, it was found that the annealing temperature is related to the electrical and thermal conductivity of the TSV materials. As a result, it is possible to improve the reliability of NAND flash memory. All the results are discussed based on 3-dimensional (3-D) simulations with the aid of the COMSOL simulator.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.12
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• pp.1983-1993
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• 1993

A power-reduction technique for full-flash A/D converters is proposed. As the resolution of a full-flash A/D converter increases linearly, the number of comparators increases exponentially. The power dissipation is generally larger than other A/D converter architectures because there are many comparators, and they are operating continuously. In this proposed architecture, only a selected number of conmarators are made to operate instead of activating all the comparators of the full-flash A/D convertor. To determine whichcomparators should be activated, voltage levelfider circuits are used. A new clock driver is developed to suppress the dynamic glitch noise which is fed back into the input stage of the comparator. By using this clock driver, the glitch noise in the current source is reduced to one fourth of that when the typical clock signal is applied. The proposed architecture has been implemented with 1.2 m 5GHz BiCMOS technology. The maximum conversion speed is 350Msamples/s. and dissipates only 900mW.

• Proceedings of the Korean Society of Computer Information Conference
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• 2014.07a
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• pp.227-229
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• 2014

플래시 메모리는 빠른 처리 속도, 비휘발성, 저 전력, 강한 내구성 등으로 인해 최근 스마트폰, 태블릿, 노트북, 컴퓨터와 같은 여러 분야에서 많이 사용하고 있다. 최근 기존에 사용하던 NAND 플래시가 미세화 기술의 한계에 봉착함에 따라 기존 2차원 구조의 NAND플래시를 대처할 장치로 3차원 수직구조 NAND 플래시 메모리(3D Vertical NAND)가 주목받고 있다. 기존의 플래시 메모리는 데이터를 효율적으로 삽입/삭제/검색하기 위해 B-tree와 같은 색인기법을 필요로 한다. 플래시 메모리 상에서 B-tree 구현에 관한 기존 연구로서는 BFTL(B-Tree Flash Translation Layer)기법이 최초로 제안되었다. 현재 3차원 V-NAND 구조의 플래시 메모리가 시작품으로 제작되어 머지않아 양산 될 예정이다. 본 논문에서는 향후 출시될 3차원 구조의 플래시 메모리에 적합한 Octree 기반의 파일시스템을 제안한다.

• Journal of the Korean Society of Safety
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• v.25 no.2
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• pp.35-40
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• 2010

Explosion limit and flash point are the major combustion properties used to determine the fire and explosion hazards of the flammable substances. In this study, in order to predict upper explosion limits(UEL), the upper flash point of n-alcohols were measured under the VLE(vapor-liquid equilibrium) state by using Setaflash closed cup tester(ASTM D3278). The UELs calculated by Antoine equation using the experimental upper flash point are usually lower than the several reported UELs. From the given results, using the proposed experimental and predicted method, it is possible to research the upper explosion limits of the other flammable substances.

• Journal of the Korean Society of Safety
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• v.26 no.4
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• pp.59-64
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• 2011

Explosion limit and flash point are the major combustion properties used to determine the fire and explosion hazards of the flammable substances. In this study, in order to predict upper explosion limits(UELs), the upper flash point of n-alkanes and aromatic compounds were measured under the VLE(vapor-liquid equilibrium) state by using Setaflash closed cup tester(ASTM D3278). The UELs calculated by Antoine equation and chemical stoichiometric coefficient tusing the experimental upper flash point were compared with the several reported UELs. From the given results, using the proposed experimental and predicted method, it is possible to research the upper explosion limits of the other flammable substances.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.909-914
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• 2007

Today's dynamic nature of the construction environment requires management systems to be active enough to take real-time decisions. For real-time decision making, effective 3D spatial information acquisition is imperative. Various 3D data acquisition technologies are being developed and tested for 3D spatial information acquisition and its use for wide range of areas in the construction industry, however, there are shortcomings in these technologies. The major problems are long processing time and high cost which make current technologies impossible to be used for real-time applications. Laser-based Flash LADAR that illuminates the entire scene with diffuse laser light is comparatively fast and cost effective, therefore it is well suited for 3D spatial modeling of dynamic environment on a construction site. This paper presents experimental results to evaluate the performance of flash LADAR and discuss issues of applicability of Flash LADAR to 3D spatial modeling on a construction site.

• The KIPS Transactions:PartD
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• v.15D no.5
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• pp.589-598
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• 2008

Recently, Mobile Computing Devices are used generally. And Information which is processed by Mobile computing devices is increasing. Because information is digitalizing. So Mobile computing Devices demand an Embedded DBMS for efficient management of information. Moreover Mobile computing Devices demand an efficient storage management in NAND-type flash memory because the NAND-type flash memory is using generally in Mobile computing devices and the NAND-type flash memory is more expensive than the magnetic disks. So that in this paper, we present an efficient Compressed Data Management System for the embedded DBMS that is used in flash memory. This proposed system improve the space utilization and extend a lifetime of a flash memory because it decreases the size of data.

• Journal of Convergence for Information Technology
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• v.11 no.9
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• pp.124-129
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• 2021

A time-interpolation technique has been applied to the conventional FLASH analog-to-digital converter (ADC) to increase a number of quantization level, thus it reduces not only a power dissipation, but also minimize an active chip area. In this work, we demonstrated 5-bit ADC which has 31 quantization levels consisting of 16 conventional voltage-mode comparators and 15 time-mode comparators. As a result, we have achieved about 48.4% voltage-mode comparator reductions. The ADC is fabricated in a 14nm fin Field-effect transistor (FinFET) process with an active die area of 0.0024 mm2 while consuming 0.82 mW through a 0.8 V supply. At 400-MS/s conversion rate, the ADC performs 28.03 dB SNDR (4.36 ENOB) at 21MHz input frequency.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.826-830
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• 2002

In the civil engineering and architecture fields, welding for large sectional members, such as I section steel and H section steel, are usually performed. a flash welding system, by which large I section steel or H section steel can be welded for a short time, was newly developed. In order to know the basic characteristics of welded joints, the specimens were cut out from flash welded joints, and tensile and fatigue experiments were carried out. The joint efficiency of welded joints by flash welding is 100% for the specimens with reinforcements and 93% for without reinforcements. The fatigue strength of welded joints with reinforcement was about 50% of that of the base metal. Removing the reinforcement generated by flash welding, fatigue strength of flash welded joints became 75% of that of the base metal. In case of flash welded joints with reinforcements, after a couple of fatigue cracks had propagated, ductile fracture occurred at the toe. In flash welded joints without reinforcements, fracture occurred at the bond or at HAZ (Heat Affected Zone). In case of fracture at the bond, fracture was brittle, and in case at HAZ, fracture was ductile.