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The Intrinsic Safety Evaluation of Solar Photovoltaic Cell (태양전지셀의 본질안전 방폭성능 평가)

  • Lee, Chun-Ha;Jee, Seung-Wook;Kim, Si-Kuk
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.7
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    • pp.49-54
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    • 2011
  • Now the world will regulate the CO2 emission due to environmental issues. For an alternative plan photovoltaic system is watched. So, photovoltaic system is trend of big city and it is mandatory for renovation of construction. Oil & gas filling station existed in city is suitable to found the photovoltaic system. But the general photovoltaic system in oil & gas filling station is difficult to found because it is classified into hazardous area. This paper evaluates intrinsic safety evaluation of solar cell for making basic data to found for the photovoltaic system on hazardous area. The intrinsic safety characteristic is evaluated by short-circuit ignition test using IEC type spark ignition test apparatus and temperature rising test. The result of short-circuit ignition test, propane-air mixture gas is exploded on condition that 4 solar cells(9[V], 90[mA]) are connected serially under insolation 800[W/$m^2$]. So, if a larger solar module will be used at oil & gas filling station than we were tested, it needs explosion proof. As the result of rising temperature test, the temperature rising due to short circuit is not so much, but when the temperature rises due to radiant heat, it demands careful consideration for environmental influence.

A Study on the Awareness & Preferences about the Elderly Care Facilities (노인 요양시설에 대한 의식 및 선호도 연구)

  • Shin, Hee-Sik;Chu, Yeon-Cheol;Youn, Chung-Yeul
    • Journal of the Korean Institute of Rural Architecture
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    • v.11 no.4
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    • pp.51-58
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    • 2009
  • The senior adults which are a central manpower of economic activity of the nation decreased and the elderly sustenance allowance already went over 10%. And the economic activity participation of the woman which are the supporter of the unpaid the elderly within the family is increasing. This big change is expected to support awareness. To respond to these changes, the improvement of social welfare system for elderly with the job of retirement lifestyles of the elderly, a figure that is needed for the ceremony. The elderly medical treatment facility that began in 2008 the elderly long-term medical treatment law enforcement because of the demand is expected to grow. It is forecast with the fact that the data which is fundamental is most important will become that old person medical treatment facility of the middle-aged layer which is a central role of the protector who decides the facility use of the preliminary consumer of the elderly care facility and currently the very the elderly and manhood ceremony and the preference to plan of the elderly welfare facility. The purpose of this study is to present the fundamental data about the elderly care facility for comparative analysis the awareness & perfernces of the elderly care facilities of the senior adults & the elderly.

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Molecular Modeling and its Experimental Verification for the Catalytic Mechanism of Candida antarctica Lipase B

  • Kwon, Cheong-Hoon;Shin, Dae-Young;Lee, Jong-Ho;Kim, Seung-Wook;Kang, Jeong-Won
    • Journal of Microbiology and Biotechnology
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    • v.17 no.7
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    • pp.1098-1105
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    • 2007
  • Quantum mechanical and molecular dynamics simulation analysis has been performed on the model system for CALB (Candida antarctica lipase B) with esters to study the reaction mechanism and conformational preference of catalytic hydrolysis and the esterification reaction. Using quantum mechanical analysis, the ping-pong bi-bi mechanism was applied and energies and 3-dimensional binding configurations of the whole reaction pathways were calculated. Further molecular dynamics simulation analysis was performed on the basis of the transition state obtained from quantum mechanical study to observe the effect of structures of the substrates. Calculation results using substrates of different chain length and chiral configurations were compared for conformational preference. The calculated results showed very small influence on chain length, whereas chiral conformation showed big differences. Calculated results from molecular modeling studies have been compared qualitatively with the experimental data using racemic mixtures of (${\pm}$)-cis-4-acetamido-cyclopent-2-ene-1-ethyl acetate as substrates.

The Buried Type Reference Electrode for Real time Wireless Remote Monitoring System for Stray Current of Subway System (지하철 누설전류의 실시간 무선 원격 감시 시스템용 매설형 기준전극)

  • Bae, Jeong-Hyo;Ha, Yoon-Cheol;Ha, Tae-Hyun;Lee, Hyun-Goo;Lee, Jae-Duck;Kim, Dae-Kyeong
    • Proceedings of the KIEE Conference
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    • 2005.07d
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    • pp.2732-2734
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    • 2005
  • In present, most of metallic structures(gas pipeline, oil pipeline, water pipeline, etc) are running parallel with subway and power line in seoul. Moreover subway system and power line make a stray current due to electrical corrosion on metallic structures. The owner of metallic structures has a burden of responsibility for the protection of corrosion and the prevention against big accident such as gas explosion or soil pollution and so on. So, they have to measure and analyze the data about P/S(Pipe to Soil) potential due to stray current of subway system. So, we have developed the Real-time Wireless Remote Monitoring System for Stray Current of Subway System. In this system, the permanent buried type reference electrode is necessary. In this paper, results of development about the permanent buried type reference electrode($Cu/CuSO_4$) are presented.

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Research for Protection Relay of Static Condenser Bank (SC 전용 보호계전기 개발)

  • Jeong, J.K.;Yun, S.Y.;Kim, S.J.;Kim, K.G.
    • Proceedings of the KIEE Conference
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    • 2006.05a
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    • pp.48-50
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    • 2006
  • SC(Static Condenser) in KEPCO is used in voltage control and power factor compensation. Currently KEPCO uses SC to 154kv 50MVA and 23kv SMVA. It is not important in old days because a SC bank accident has no effect on power system. But we are interested in the SC bank for power quality in these days. The SC Bank has a reactor and a condenser using series connection. It is operated in critical point for resonance circuit normally. Therefore the SC bank has a small reliability against other Power instruments. If a 4th harmonic frequency as a resonance frequency is supplied in system, the condenser is damaged because of a resonance current. And a trip and a closing for CB(Circuit Breaker) in many times will have a big influence of SC bank destruction. General OCR(Over Current Relay) observing SC bank is not useful for this protection We think that protection relay must be have the SC bank characteristics. A solution for this problem is active Power, resonance frequency and impedance.

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Determining Diffusion Power Users in a Blog Network (블로그 연결망에서 파급력을 가진 파워 유저의 파악 기법)

  • Lim, Seung-Hwan;Kim, Sang-Wook;Park, Sun-Ju
    • Journal of KIISE:Computing Practices and Letters
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    • v.16 no.4
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    • pp.377-382
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    • 2010
  • For business purposes, it is important to identify diffusion power users, a group of users who have big influence on other users in diffusing content. In this paper, we use the independent cascade model for determining diffusion power users, and to do so, we need a method for calculating the assimilation probability between users. This paper proposes the concepts of user delivery power and a way to quantifying the value of this. User delivery power is used to compute the assimilation probability with user content power. We analyze the proposed method by comparing its performance with those of existing methods through experiments using a real blog network data.

Saussurea grandicapitula W. Lee et H. T. Im (Compositae), a New Species from the Taebaek Mountains, Korea (택배취, 취나물속의 일신종)

  • Lee, Woo-Tchul;Im, Hyoung-Tak
    • Korean Journal of Plant Taxonomy
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    • v.37 no.4
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    • pp.387-393
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    • 2007
  • Saussurea grandicapitulata, a new species of Saussurea, was repodrted in the Taebaek Mountains. It has peculiar morphological characters, easily distinguisable from other Saussurea in Korea and Japan; robust plant size, pale green leaf beneath, purplish brown-cobwebby hairs on petioles of radical and lower cauline leaves, few heads with not so long pedicel, big globose involucres with brown-cobwebby hairs, and often recurved long phyllaries. S. grandicapitula is an endemic species to Korea which was differentiated in consequence of adaptation to heavy snowy environment of the Taebaek Mountains.

Standardized Surveying Method of Rural Amenity Resources with Database Normalization Technique (자료정규화를 통한 농촌어메니티자원 조사표의 표준화)

  • Kim, Sang-Bum;Rhee, Sang-Young;Jung, Nam-Su;Lee, Ji-Min;Cho, Soon-Jae;Lee, Jeong-Jae
    • Journal of Korean Society of Rural Planning
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    • v.10 no.4 s.25
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    • pp.1-7
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    • 2004
  • In Korea, rural community has been becomming unstable by declining of agriculture. In order to solve this problem, there were some trials to activate rural communities by maintaining rural amenities. But, it is difficult to use rural amenities as a development factor to promote rural communities because there are few researches about quantifying rural amenities. In this study, a method fer quantifying rural amenities is suggested using database normalization technique. Previous thirty seven surveying items of rural amenity resources are formally reduced to five common surveying items, seven resources, and eleven surveying tables. Finally, big picture of rural amenity resource map with surveying data for rural development is suggested.

Diagnosis Accuracy Rate Comparative Study of Each Sasang Constitutions and Sex Distinction by Body Measurement Method between 3D Body Measuring Instrument and Hand-operating (3D체형측정기와 수동측정 방법간의 사상체질별 ${\cdot}$ 성별 진단정확률 비교연구)

  • Kwon, Suk-Dong;Sul, Yu-Kyung;Lee, Eui-Ju;Kim, Kyu-Kon;Kim, Jong-Won
    • Journal of Sasang Constitutional Medicine
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    • v.19 no.1
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    • pp.60-77
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    • 2007
  • 1. Objectives This is the comparative study with hand-operated measurement method and Automatic measurement method, in order to convert the automatic measurement method. 2. Methods We measured the body of patients(hand-operated Width 5 Places and hand-operated circumference 8 place,Automatic Width 5 and automatic circumference 8 place by 3D body measuring instrument) and analyzed the anthropometric data divding into sex&age. 362 patient's data are used in the analysis. 3. Results and Conclusions 1) 1th circumference variable which standing was not a sasang constitutional difference. 2) Diagnostic accuracy rate of the body measurement was 50-80%. 3) Diagnostic accuracy rate of man is higher than Diagnostic accuracy rate of women 4) Diagnostic accuracy rate of Automatic & hand-operated measuring was not a big difference.

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NON-POINT SOURCE POLLUTANT MODELING IN USING GIS ASSESSMENT IN STREAM NETWORK AND THE IRRIGATION REGION

  • Ju-Young;Kutty Arvind
    • Water Engineering Research
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    • v.5 no.3
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    • pp.147-156
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    • 2004
  • Recently, the population growth, industrial and agricultural development are rapidly undergoing in the Lower Rio Grande Valley (LRGV) in Texas. The Lower Rio Grande Valley (LRGV) composed of the 4 counties and three of them are interesting for Non-point and point source pollutant modeling: Starr, Cameron, and Hidalgo. Especially, the LRGV is an intensively irrigation region, and Texas A&M University Agriculture Program and the New Mexico State University College of Agriculture applied irrigation district program (Guy Fipps and Craig Pope, 1998), projects in GIS and Hydrology based agricultural water management systems and assessment of prioritized protecting stream network, water quality and rehabilitation based on water saving potential in Rio Grande River. In the LRGV region, where point and non-point sources of pollution may be a big concern, because increasing fertilizers and pesticides use and population cause. This project objective seeks to determine the accumulation of non-point and point source and discuss the main impacts of agriculture and environmental concern with water quality related to pesticides, fertilizer, and nutrients within LRGV region. The GIS technique is widely used and developed for the assessment of non-point source pollution in LRGV region. This project shows the losses in kg/$km^2$/year of BOD (Biological Oxygen Demand), TN (total Nitrogen) and TP (total phosphorus) in the runoff from the surface of LRGV.

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