• Title/Summary/Keyword: Charge Exchange

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Heuristic for the Simultaneous Target Allocation and Fire Sequencing Problem (표적 할당과 사격 순서의 동시 결정 문제를 위한 발견적 기법)

  • Kim, Dong-Hyun;Lee, Young-Hoon
    • Journal of the Korean Operations Research and Management Science Society
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    • v.35 no.1
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    • pp.47-65
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    • 2010
  • In this study the artillery fire system is investigated in consideration of the characteristics of the troop and the target. Two kinds of decision are to be made on the target allocation with fire ammunition and the fire sequencing for the target with duties in charge. The objective is to minimize the completion time for all troops. Each target has the specified amount of load of fire, which can be accomplished by a single troop or the combination of the troops having different capabilities. Mathematical model is suggested, and the heuristic algorithm which yields a solution within a reasonable computation time is developed. The algorithm consists of iterative three steps : the initial solution generation, the division improvement, and the exchange improvement. The performance of the heuristic is evaluated through the computational experiment

Chemical composition of Am stars: RR Lyn and $\rho$ Pup

  • Yushchenko, A.V.;Lee, J.J.;Kang, Y.W.;Doikov, D.N.
    • Bulletin of the Korean Space Science Society
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    • 2008.10a
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    • pp.22.3-22.3
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    • 2008
  • We present the results of the investigations of high dispersion spectra of two stars. These are the eclipsing binary RR Lyn, and $\rho$ Pup - the prototype of the group of pulsating variables. The spectra were obtained at 1.8 m Bohyuunsan observatory telescope, and 8.2 m VLT. We found the chemical composition. The both components of RR Lyn are Am stars (metallic line stars), but the abundance patterns of the components are not similar - the iron abundance and the abundances of other elements are surely different. For few elements the differences exceeds 1 dex. We found the abundances of 56 chemical elements in the atmosphere of $\rho$ Pup. This is one of the best stellar abundance patterns. It permits to investigate the role of the charge-exchange reactions in stellar atmospheres. These reactions can produce the abundance anomalies in the atmospheres of B-F type stars. These reactions can be one of the sources of galactic cosmic rays, and the reason of the braked rotation of A-F type chemically peculiar stars.

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A Study About Necessity of a Teacher Center for Elementary and Middle School Teachers (초.중등교사를 위한 교사 센터 설립에 관한 연구)

  • Chang, Won-Hie
    • Journal of the Korean Institute of Educational Facilities
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    • v.5 no.4
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    • pp.18-27
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    • 1998
  • Our gorvernment announced an educational reformation bill to establish the institutional foundation of educational system on May 31, in 1995. To secure the open education which is to foster students' creativity, individualization and personalization, it was requested that the past teacher-centered system should be changed to learner-centered system. To gurantee such a change, however, there are many conditions that has to be satisfied first. I think that the most important thing for the new system is a close interaction between teachers and students. To accomplish a successful interaction, the teachers' understanding and attitude toward their students must change at first. The purpose of this study is to examine what kind of understanding and attitude the teachers need, and what kind of roles teachers must take charge of. At the same time, I suggest that we need to establish a Teacher Center to give teachers a seperate place to learn new theories, and to exchange among themselves the informations they got from the actual field experience.

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Calculation of ion distribution in an RF plasma etching system using monte carlo methods (몬테카를로 계산 방식에 의한 RF 플라즈마 에칭 시스템에서의 이온 분포 계산)

  • 반용찬;이제희;윤상호;권오섭;김윤태;원태영
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.35D no.5
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    • pp.54-62
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    • 1998
  • In a plasma etching system, ions become an important parameter in determining the wafer topography which depends on both the physical sputtering mechanism and the chemically enhanced reaction. this paper reports the energy and angular distributions of ions across the plasma sheath using a monte carlo method. The ion distribution is mainly affected by the magnitude of the sheath voltage and by the collision in the sheath. Furthemore, the local potential distribution in a plamsa sheath has been determined by solving the poisson's equation. In th is work, ionic collisions were cosidered in terms of both charge exchange and momentum transfer. The three-dimensional distributions of ions were calculated with varying the input process conditions in the plasma reactor.

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Manufacture of Sterilizing Media with Shell Powder and It's Application to the Filter of Water Clarifier (패각분말을 이용한 살균성 메디아의 제조 및 정수기용 필터에 대한 응용)

  • Shin, Choon-Hwan
    • Journal of Environmental Science International
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    • v.15 no.11
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    • pp.1027-1034
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    • 2006
  • Antimicrobial powder was made by exchanging silver ion on calcined oyster shell. On the purpose of application to water clarifier, bail-type media mixed with antimicrobial powder and $0{\sim}30%$ white kaoline were made. The sterilization effect, pore size distribution and zeta potential was tested to indicate the condition for the media of water clarifier. From these tests, it was confirmed that this media have an excellent sterilization power on $G^-\;and\;G^+$ germs. As the concentration of the exchanged silver ion increased, the surface charge density of the anions on the surface of the media also increased. The surface pore size decreased with the concentration of silver ion and 20% more white kaoline ratio. Consequently, mixing ratio of white kaoline would appear to indicate the optimun condition as media have sterilization power.

SPECTRAL DIAGNOSTICS OF THE ENERGETIC PARTICLES IN SOLAR FLARES

  • FANG C.;DING M. D.;HENOUX J. C.;GAN W. Q.
    • Journal of The Korean Astronomical Society
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    • v.29 no.spc1
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    • pp.295-298
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    • 1996
  • Non-LTE calculations, with the non-thermal ionization effects included, indicated that for electron bombardment, the H$\alpha$ line is widely broadened and shows a strong central reversal. Significant enhancements at the line wings of Ly$\alpha$ and Ly$\beta$ are also predicted at the beginning of the impulsive phase of flares. For the proton bombardment, no strong broadening and no large central reversal are expected. However, due to proton-hydrogen charge exchange, the enhancements at the red wings of Ly$\alpha$ and Ly$\beta$ lines at the early impulsive phase of flares are significant. Our results show that the electron beam can also in some cases generate visible and UV continuum emission in white-light flares. However, at the onset phase, a negative flare may appear within several seconds, due to the increase of the H- opacity. Another spectroscopic signature of energetic particles, i.e. the impact polarization of atomic lines, is also mentioned.

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A Study on the Merchant's Costume in Enlightment Period of Korea (개화기(開化期)의 상인(商人) 복장(服裝))

  • Nam, Yun-Suk;Chon, Hye-Suk
    • Journal of the Korean Society of Costume
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    • v.8
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    • pp.15-27
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    • 1984
  • A costume study is a part of the cultural history and also has the greatest relation to life's senses as a concrete culture. Korean costume that consists a double structure with Chinese one through Chosun Dynasty five hundred years, has recently changed up to the Western Form. In this respect Korean Costume has a important meaning in relation to Western costume. Traditional costume, generally speaking, has tendency to keep up by the common people than the higher classes. Then there were four classes. They are aristocratic classes common people, those who are engaged in the form, industry, trade and low classes. Merchant of them partially took charge of the cultural exchange about contacting with tradition and new one. Because it's easy to flow in one's character the new civilization. So there is an important significance to research of the merchant's costume in Gae Hwa Gi changing age of civilization in politics, economic, and social system. The records appeared about the merchant's costume in the age of civilization through literature study and natural photo at that time.

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Ag-modified BiOX (X=Cl, Br and I) Plates for Photocatalytic Dye Removal

  • Lee, Seung-Won;Choe, Yeong-In;Lee, Ju-Heon;Park, Yo-Han;Son, Yeong-Gu
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.424.2-424.2
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    • 2014
  • Ag-modified BiOX (X=Cl, Br and I) nanoplates were synthesized by an ion-exchange reaction. We examined the fundamental properties by scanning electron microscopy (SEM), electron transmission microscopy (TEM), X-ray diffraction, UV-visible absorption, Fourier-transform infrared and photoluminescence spectroscopy. The adsorption and photocatalytic performances of the catalysts were tested with dyes under UV and visible light. A chemical scavenger method was employed to test the roles of active species (${\cdot}OH$, ${\cdot}O2-$ and h+) and understand photodegradation mechanism. Photoluminescence spectroscopy was used to examine ${\cdot}OH$ radical formation using terephthalic acid during photoirradiation.

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Design and test of two-way communications technologies applicable to Smart meter (스마트미터에 적용 가능한 양방향 통신방식 설계 및 실험)

  • Lee, Sang-il
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.05a
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    • pp.941-943
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    • 2013
  • A standardized communication protocol is required to exchange the data of electric charge and current-using electric power through the two-way communications between the smart meter and electric power supplier. In this paper, a two-way communications technologies is designed for control technologies and de/registration services of electric equipment, and the international communication protocols is applied to the communications technologies.

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A Feasibility Study of Low-Cost Hybrid Fuel-Cell System for Ship Auxiliary Power (선박 보조전원을 위한 저가형 하이브리드 연료전지 시스템 적용 타당성 연구)

  • Yang, Geun Ryoung;An, Sang Yong;Choo, Jin Hoon
    • New & Renewable Energy
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    • v.9 no.4
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    • pp.3-12
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    • 2013
  • This paper proposes the hybrid fuel cell system that can solve disadvantages of existing fuel cell system and ensure high reliability and high stability. The system consists of PEM fuel cell, Ni-MH battery and power management system. In this system, when the power provided from the fuel cell is higher than the load power, the extra energy may be used to charge the Ni-MH battery. When the fuel cell can not provide enough energy to the load, the shortage of energy will be supplied by the Ni-MH battery. Experimental results show that the output voltage is regulated well during load variations. Also, high system efficiency is achieved.