• Title/Summary/Keyword: RT structure

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ERROR ESTIMATES OF RT1 MIXED METHODS FOR DISTRIBUTED OPTIMAL CONTROL PROBLEMS

  • Hou, Tianliang
    • Bulletin of the Korean Mathematical Society
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    • v.51 no.1
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    • pp.139-156
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    • 2014
  • In this paper, we investigate the error estimates of a quadratic elliptic control problem with pointwise control constraints. The state and the co-state variables are approximated by the order k = 1 Raviart-Thomas mixed finite element and the control variable is discretized by piecewise linear but discontinuous functions. Approximations of order $h^{\frac{3}{2}}$ in the $L^2$-norm and order h in the $L^{\infty}$-norm for the control variable are proved.

The strength evaluation of European Diesel Multiple Unit(DMU) (유럽형 디젤 동차 차체의 강도 평가)

  • Choi, Jeong-Yong;Kim, Seung-Tech;Park, Geun-Soo;Park, Hyung-Soon
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.836-842
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    • 2007
  • Recently it is a tendency that Diesel rolling stock is committing in the commuter's train route of the suburb for solving commuting traffic congestion. It has advantage which expense of diesel rolling stock is relatively cheaper than electric rail car or high-speed train. In addition, it can be using the exist route without large-scale facility investment. Because of this advantage, the demand of diesel rolling stock occupy regular portion from overseas railway car market. GM/RT 2100 specifies the loads vehicle bodies shall be capable of withstanding, identifies how material data shall be used and presents the principles to be used for design verification by analysis. Therefore, in order to fulfill the structural requirements, Rotem Company has carried out Finite Element Analysis (FEA) to verify whether the carbody structure has enough strength to withstand the loads specified by GM/RT 2100. This research contains the results obtained by the analysis. The analysis was carried out using I-DEAS 12 NX Series

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STM Study of Nb Clusters on Ag(110)

  • 윤홍식;이준희;양경득;여인환
    • Proceedings of the Korean Vacuum Society Conference
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    • 1999.07a
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    • pp.173-173
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    • 1999
  • The initial growth mode of Nb on Ag(110) in sub-monolayer region is studied using Scanning Tunneling microscopy. E-beam evaporated Nb is deposited onto the substrate at RT, and STM measurements are carried out at RT and 78K. With Nb being immiscible in bulk Ag, 3D islands formation begins at early stage and no particular ordered structure is found. At very low coverages, however, many interesting phenomena are observed in association with Nb clusters. Small Nb clusters as deposited displays very strong size dependence against atom-manipulation by the STM tip. In addition, the apparent corrugation of clusters below the critical size exhibits dramatic dependence on the imaging bias, disappearing completely over a wide range of the bias. Possible physical mechanism responsible for such behavior will be discussed.

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Compiling Multicopy Single-Stranded DNA Sequences from Bacterial Genome Sequences

  • Yoo, Wonseok;Lim, Dongbin;Kim, Sangsoo
    • Genomics & Informatics
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    • v.14 no.1
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    • pp.29-33
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    • 2016
  • A retron is a bacterial retroelement that encodes an RNA gene and a reverse transcriptase (RT). The former, once transcribed, works as a template primer for reverse transcription by the latter. The resulting DNA is covalently linked to the upstream part of the RNA; this chimera is called multicopy single-stranded DNA (msDNA), which is extrachromosomal DNA found in many bacterial species. Based on the conserved features in the eight known msDNA sequences, we developed a detection method and applied it to scan National Center for Biotechnology Information (NCBI) RefSeq bacterial genome sequences. Among 16,844 bacterial sequences possessing a retron-type RT domain, we identified 48 unique types of msDNA. Currently, the biological role of msDNA is not well understood. Our work will be a useful tool in studying the distribution, evolution, and physiological role of msDNA.

Optically Pumped Stimulated Emission from Column-III Nitride Semiconductors. (III족 질화물반도체의 광여기 유도방출)

  • 김선태;문동찬
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1994.11a
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    • pp.50-53
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    • 1994
  • In this study. we report the properties of optically pumped stimulated emission at room temperature (RT) from column-III nitride semiconductors of GaN, GaInN, AlGaN/GaN double hetero-structure (DH) and AlGaN/GaInN DH which grown by low pressure metal-organic vapor phase epitaxy on sapphire substrate using an AIN buffer-layer. The peak wavelength of the stimulated emission at RT from AlGaN/GaN DH is 370nm and the threshold of excitation pumping power density (P$\_$th/) is about 89㎾/$\textrm{cm}^2$, and they from AlGaN/GaInN DH are 403nm and 130㎾/$\textrm{cm}^2$, respectively. The P$\_$th/ of AlGaN/GaN and AlGaN/GaInN DHs are lower than the bulk materials due to optical confinement within the active layers of GaN and GaInN. The optical gain and the polarization of stimulated emission characteristics are presented in this article.

Detection and Genomic Analysis of Viroid-like RNA Molecules Isolated from Korean Peonies (한국산 작약에서 분리한 바이로이드 유사 RNA 분자의 확인과 유전자 분석)

  • 정동수;김무인;이재열
    • Korean Journal Plant Pathology
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    • v.13 no.2
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    • pp.113-117
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    • 1997
  • Low moleuclar weight (LMW) RNAs were isolated form Korean peonies which expressed symptoms of stunt and epinasty. The LMW plant RNAs were purified by Qiagen column chromatography which could separate viroid specific nucleic acid at differential salt concentration. After the inoculation of the purified RNAs from the peonies, the inoculated tomatoes (cv. Rutgers) expressed the symptoms of stunt and epinasty. Also the same molecular weight RNAs with viroid-like RNAs were isolated from the inoculated tomatoes. Double-stranded cDNA were synthesized by the methods of reverse transcription (RT) and polymerase chain reaction (PCR) with the purified RNA and primers. The same cDNAs associated with viroid-like RNAs wre cloned from the inoculated tomatoes. The cDNA has been sequenced and its 375-nucleotides were arranged into secondary structure. The cloned cDNA showed 47~54% homology compared with other viroids. The sequence homology of the cloned cDNA were partially high with plant genomic RNAs.

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Time Service Guranteeing in Real-Time Distributed Simulation Object Oriented Programming

  • Kim, Hee-Chul;Kim, Gwang-Jun;Kim, Moon-Hwan;Ra, Sang-Dong;Bae, Chul-Soo
    • Proceedings of the IEEK Conference
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    • 2002.07c
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    • pp.1843-1846
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    • 2002
  • The object-oriented(OO) distributed real- time(RT) programming movement started in 1990’s and is growing rapidly at this turn of the century Distributed real-time simulation is a field in its infancy but it is bounded to receive steadily growing recognition for its importance and wide applicability. The scheme is called the distributed time-triggered simulation scheme which is conceptually simple and easy to use but widely applicable. A new generation object oriented(00) RT programming scheme is called the time-triggered message triggered object(TMO) programming scheme and it is used to make specific illustrations of the issues. The TMO structuring scheme is a general-style components structuring scheme and supports design of all types of component including hard real time 1 objects and non real time objects within one general structure.

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Object Oriented Real Time Distributed Programming and Time-triggered Message-triggered Object(TMO) Scheme

  • Kim, Gwang-Jun;Ra, Sang-Dong;Bae, Chul-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.10A
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    • pp.990-999
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    • 2002
  • The object-oriented(OO) distributed real-time(RT) programming movement started in 1990's and is growing rapidly at this turn of the century. Distributed real-time simulation is a field in its infancy but it is bounded to receive steadily growing recognition for its importance and wide applicability. The scheme is called the distributed time-triggered simulation scheme which is conceptually simple and easy to use but widely applicable. A new generation object oriented(OO) RT programming scheme is called the time-triggered message triggered object(TMO) programming scheme and it is used to make specific illustrations of the issues. The TMO structuring scheme is a general-style components structuring scheme and supports design of all types of component including hard real time objects and non real time objects within one general structure.

Ag(100) 기판위에 증착된 Nb Cluster에 관한 STM연구

  • 윤홍식;유미애;한권환;이준희;양경득;여인환
    • Proceedings of the Korean Vacuum Society Conference
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    • 2000.02a
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    • pp.140-140
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    • 2000
  • The initial growth mode of Nb on Ag(11) in sub-monolayer regime and the influence of subsequent 520K annealing are studied using UHV Scanning Tunneling Microscopy. E-beam evaporated Nb is deposited onto the substrate at RT, and STM measurements are carried out at RT and 78 K. With Nb being immiscible in bulk Ag, 3D islands formation begins at early stage and no particular ordered structure is found. After annealing to 520K, most of islands are disappeared from terrace. There exist 2 possibilities. : (1) Diffusion of Nb into the 2nd or 3rd layer of Ag substrate or (2) agglomeration of Nb on Ag at higher temperature. A model will be given to explain the evidence. In addition, we investigated the change of STM image according to bias voltage depending on island size. Possible physical mechanism responsible for such behavior together with interaction between Nb islands and reactive gases will be also discussed.

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HYBRIDIZATION EFFECTS IN $RT_2$ COMPOUNDS (R = Ce, Pr, Nd, Sm, Gd; T = Fe, Co, Ni)

  • Kang, Kicheon;Min, B.I.;Kang, J.S.
    • Journal of the Korean Magnetics Society
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    • v.5 no.5
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    • pp.376-379
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    • 1995
  • Employing the muffin-tin-orbital theory combined with pseudo-potential concepts, we have evaluated hybridization matrix elements between R and T sites in $RT_{2}$ compounds. The matrix elements are calculated with two parameters, the interatomic distance between R and T atoms from the crystal structure data, and the expectation values of the radial distances for the radial wave functions of the ground state charge densities, which are obtained from the linearized muffin-tin orbital band method within the local density approximation. It is found that the R 4f/T 3d hybridization matrix elements decrease with an increasing atomic number from R=Ce to Gd, and that they are smaller in $RNi_{2}$ than in $RCo_{2}$, which are consistent with trends observed in recent photoemission spectroscopy experiments. It is also found that the magnitudes of the hybridization matrix elements in $RFe_{2}$ are comparable to those in $RNi_{2}$.

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