• 방재기술
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• 통권29호
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• pp.39-45
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• 2000

All objects emit thermal radiation and this radiation is the basis of the techniques used to detect flames. The usual phenomena occurring in the initial stage of a fire are generally invisible products of a combustion and visible smoke. Liquid or gaseous materials do not undergo a smoldering stage such fires develop very rapidly. Also, the heat generated by the initial flames is usually not sufficient to active a heat detector. In this case the most effective criterion for automatic fire detection is the flame. In fire regulation of korea, the compulsory standard provided that a flame detector shall be installed a place of the attachment hight of detector is higher than 20 m, chemical plants, hangar, refinery, etc.. The result of the research and development are discriminated between a flame and other radiant emitters, developed PZT pyroelectric element is based on the use of photo-voltanic cell, developed IR band-pass filter that only allow a 4.3 radiation wavelength to reach the sensors and developed IR flame detector.

• 대한산업공학회지
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• 제26권3호
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• pp.238-248
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• 2000

Facilities are getting more automated and informative in modern manufacturing systems, especially in semiconductor and LCD plants. These systems keep a great deal of such information on its current and near-future status as the arrival time and job completion time of their parts. This paper presents an efficient policy for AGV and part routing using information on the future status of the system where AGVs are playing a central role for material handling. Efficient control of AGVs is very important because AGV systems often become the bottleneck and limit the total production capacity of a very expensive plant. The cell controller records the future events chronologically in Next Event Schedule, and uses this list to determine to which place the AGVs and parts to be sent.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.571-573
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• 2007

It is known that the main source of the area image sticking is the ion charge adsorption on the alignment layer. We found out that the adsorption of the ion charge of the liquid crystal in the cell was physisorption, which takes place between all molecules on any surface providing the adsorption force is small.

• Transactions on Electrical and Electronic Materials
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• 제16권3호
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• pp.146-150
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• 2015

Insulation breakdown voltage and insulation lifetime were investigated in straight lines or twisted pairs with polyesterimide-polyamideimide enameled round wires (EI/AIW ). The enamel thickness was 50 μm and the conducting copper radius was 0.50, 0.75, 1.09, and 1.50 mm, respectively. There were many air gaps in a twisted pair therefore, when voltage was applied to the twisted pair, enamel erosion took place in the air gap area because of partial discharge according to Paschen's law. Insulation breakdown voltage and insulation lifetime were highest in the sample of 0.75 mm conductor radius, which was higher than those values for 0.50 mm or 1.09 and 1.55 mm.

• Archives of Pharmacal Research
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• 제28권8호
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• pp.963-969
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• 2005

Many reports have stated that some of the pathogenic bacteria can obtain iron from ferroproteins, such as cytochrome C, ferritin, hemin, hemoglobin, and myoglobin. These reports prompted us to determine if an opportunistic pathogenic fungus, Candida albicans, can utilize ferroproteins to circumvent the iron-regulatory effect of transferrin. The following assays were carried out to measure in vitro growth stimulation by the ferroproteins: as an initial step, C. albicans was cultured in iron-free (pretreated with apotransferrin for 24h) culture medium. Once Candida albicans yeast cell growth reached stasis from iron starvation, individual ferroproteins were added to the culture media. Results showed that hemin, hemoglobin, and myoglobin supported a partial growth recovery. Additional studies with haptoglobin, a serum protein that interacts with the globin moiety of certain ferroproteins, established that C. albicans could obtain iron from the haptoglobin-ferroprotein complexes. These data indicate that the heme part of the ferroproteins is the source of iron. This implies that heme oxygenase, CaHMX1 might be involved in bringing about dissociation of heme-containing protein for iron-acquisition. In addition, anticandidal activity of transferrin takes place not only by the process of iron regulation, but also by direct interaction with the yeast cells.

• 한국수소및신에너지학회논문집
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• 제11권4호
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• pp.179-188
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• 2000

The anodic reaction of hydrogen/oxygen gas mixture at platinum or palladium electrode interfacing with a solid polymer electrolyte was investigated using AC impedance method. The impedance spectrum of the electrode reactions of the mixture depends on the gas composition, electrode roughness, the mode of electrochemical operation and the cell potential. For electrolysis mode of operation, the spectrum taken for the reaction on a rough platinum electrode for the gas mixture revealed clearly that the local anodic reduction of oxygen gas takes place concurrently with the anodic oxidation of hydrogen gas.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.17-20
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• 2000

Over the years of decades, the memory technology has progressed a long, marble way. As we have evidenced from the Intel’s 1Kb DRAM in 1970 to the Gigabit era of 2000’s, the road further ahead towards the Terabit era will be unfolded. The technology once perceived inconceivable is in realization today, and similarly roadblocks as we know of today may become trivial issues for tomorrow. For the inquiring mind, the question is how the “puzzle” of tomorrow’s memory technology is pieced-in today. The process will take place both in evolutionary and revolutionary ways. Among these, note-worthy are the changes in DRAM architecture and the cell process technology. In this paper, some technical approaches will be discussed to bring these aspects into a general overview and a perspective with possibilities for the new memory technology will be presented.

• Advances in concrete construction
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• 제4권4호
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• pp.305-317
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• 2016

Porous materials such as concrete could be subjected to aggressive ions transport. Durability of cement paste is extremely depended on water and ions penetration into its interior sections. These ions transport could lead different damages depending on reactivity of ions, their concentrations and diffusion coefficients. In this paper, chloride diffusion process in cement hydrates is simulated at atomistic scale using molecular dynamics. Most important phase of cement hydrates is calcium silicate hydrate (C-S-H). Tobermorite, one of the most famous crystal analogues of C-S-H, is used as substrate in the simulation model. To conduct simulation, a nanopore is considered in the middle of simulation cell to place water molecules and aggressive ions. Different chloride salts are considered in models to find out which one is better for calculation of the transport properties. Diffusion coefficients of water molecules and chloride ions are calculated and validated with existing analytical and experimental works. There are relatively good agreements among simulation outputs and experimental results.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2010년도 춘계학술대회
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• pp.658-661
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• 2010

태양에너지의 활용은 새로운 산업의 창출과 함께 다양화 되고 있다. 본 연구에서는 태양에너지를 이용하기 위한 단일 모듈 형태의 전원공급시스템을 구현함으로써 공간적 지배를 받지 않고 전기 공급이 어려운 곳에서도 전기를 효율적으로 충전하고 간편하게 사용할 수 있는 개선된 성능의 전원공급시스템을 개발하고자 한다.

• 대한전자공학회논문지
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• 제24권1호
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• pp.149-158
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• 1987

This paper describes the SEAS which is a 2-dimensional graphic editor for schematic circuit and IC mask layout. This system runs on general purpose computer and Tektronix 4110 series graphic terminal. With this system, user can edit schematic circuits and/or IC mask layout with 2 level hierarchy. This system supports more than 20 kinds of built-in symbol, user definable internal symbols, 60 macros, 16 function keys, 4 level on-screen menu operation and edit-in-place of cell in main drawing. And it provides editing functions such as reflection, rotation, move and copy of one or a group of elements, and modification of polygona geometry etc. To improve the excution speed, we used local memory of graphic terminal. For the portability of the program, the system is written in FORTRAN 77 programming language.