• Title/Summary/Keyword: Modem.

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The development of the KTX realtime control network$(Tornad^*)$ physical layer based on FPGA (FPGA기반의 KTX용 실시간 제어네트워크$(Tonard^*)$ 물리계층 개발)

  • Hwang, Seung-Kon;Park, Jae-Hyun
    • Proceedings of the KSR Conference
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    • 2007.05a
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    • pp.1735-1740
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    • 2007
  • Communication network in KTX (Korea Train eXpress), the express train system, has to transmit status variables periodically within tens of seconds and real-time control informations which has short reply like status transition or alarm. KTX uses $Tornad^*$ (TOken Ring Network Alsthom Device) network for this purpose. This network can send and receive messages which enable express train applications embedded in intelligence boards to communicate by itself. Layer 1, 2 of $Tornad^*$ is implemented with differential manchester encoding and IEEE 802.4 standard(token bus standard) respectively. To implement layer 1 and 2, we implemented twisted pair modem using FPGA for layer 1 and used MC68824 from Motorola for layer 2. MC68824 bus arbitration and memory controller is implemented using CPLD.

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Efficient calculation method of derivative of traveltime using SWEET algorithm for refraction tomography

  • Choi, Yun-Seok;Shin, Chang-Soo
    • 한국지구물리탐사학회:학술대회논문집
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    • 2003.11a
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    • pp.402-409
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    • 2003
  • Inversion of traveltime requires an efficient algorithm for computing the traveltime as well as its $Frech\hat{e}t$ derivative. We compute the traveltime of the head waves using the damped wave solution in the Laplace domain and then present a new algorithm for calculating the $Frech\hat{e}t$ derivative of the head wave traveltimes by exploiting the numerical structure of the finite element method, the modem sparse matrix technology, and SWEET algorithm developed recently. Then, we use a properly regularized steepest descent method to invert the traveltime of the Marmousi-2 model. Through our numerical tests, we will demonstrate that the refraction tomography with large aperture data can be used to construct the initial velocity model for the prestack depth migration.

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Optics in China: past, present and future

  • Gan, Fuxi
    • Proceedings of the Optical Society of Korea Conference
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    • 2000.02a
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    • pp.68-68
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    • 2000
  • In this paper a very brief review of historical development of optical science and technology in China is presented. More attention has been pain on Modem Optics, which developed since 1950s. The recent development of optical science and technology in following fields are introduced. 1. Optical engineering and instrumentation (tracking theodolites, high speed cameras, satellite laser ranging systems, satellite flying attitude control, cameras for remote sensing, astronomical optical instrument) 2. Applied optics (adaptive optics, optical metrology, infrared optics, optical processing, optical holography) 3. Laser science and technology (ultrashort pulse lasers, UV-X ray lasers, high power laser facilities and laser fusion, laser isotope separation) 4. Laser and nonlinear materials (rare earth elements doped laser glasses and crystals, tunable laser crystals, borate series and organic nonlinear crystals) 5. Optoelectronic science and technology (Optical communication, optical data storage, optical computing) The current situation and developing prospect of optical and optoelectronic industry in China are presented. Furthermore it points out that the optical industry could be developed vigorously only if products development capacity is enhanced and new products industrialization is heightened. The main research and education institutions in the optics field in China, as well as the Chinese Optical Society (COS) are introduced.

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Orange Image on the Modern Fashion(Part II) (현대패션에 나타난 주황색 이미지(제2보))

  • 주소현;이경희
    • Journal of the Korean Society of Clothing and Textiles
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    • v.26 no.9
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    • pp.1331-1341
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    • 2002
  • The purpose of the study is to clarify orange image in the modem fashion. So kinds of costume sample being visual power in orange have been selected from photographs in fashion magazines and divided into the tones : mist(Vp, Lgr, L), bright(p, B), vivid(S, V, Dp). The study was measured by using 27 semantic differential hi-polar scales. The subjects were 50 female students majoring in clothing and textiles, The data was analyzed using the statistical SPSS package. The data were collected using self-administred questionnaires and analyzed by MDS, Cluster Analysis, ANOVA Sheff test and Regression analysis. The major findings of this research were as follows. 1. Evaluaion dimension of orange was classified as Feminine-Mannish, Lively-Mist.2. There were significant difference in visual evaluation of tones.3. The image effect on Preference, Buying needs, Pleasant and Riches was consist of complicated sensibility.

A Study on the Image-Virtualization in Fashion Illustration (패션 일러스트레이션에서의 이미지 가상화 연구)

  • Kim, Soon-Ja
    • Journal of the Korean Society of Clothing and Textiles
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    • v.32 no.3
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    • pp.505-516
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    • 2008
  • Image which appears in fashion illustration on the late twentieth century is not the representative image as an equivalence to the real fashion styles but the virtual image which bears no relation to any reality. The purpose of this study is review the concept of virtuality and analyze in which way virtual image is expressed in fashion illustrations on the background of Jean Baudrillard's simulacre theory. In post-modem paintings the expression methods of image-virtualization were image mixing through photo-image appropriation, image overlapping, and the icons inserted unreasonably, the focus-out effect through scrubbing and the over-painting on the photograph. Image-virtualization in fashion illustration was expressed through image mixing and expression of image uncertainty. Image mixing was made by photo-image appropriation, image overlapping, connection of heterogeneous images and using interface image, and uncertain image was expressed through the expression of visual ambiguity and virtual movement.

Phanerozoic Geodynamics of the Korean Peninsula (한반도의 조구조 진화)

  • Min, Kyung-Duck;Lee, Youn-Soo
    • Economic and Environmental Geology
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    • v.39 no.4 s.179
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    • pp.353-368
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    • 2006
  • The modem kinematic behaviors of the rigid block motions are well developed using synthetic analyses of paleomagnetic, petrologic, paleontologic and geophysical data which have been established in the last a quater of a century. Phanerozoic geodynamic evolution and tectonic episodes of the Korean Peninsula and East Asia region are discussed and summarized here.

TMR Contribution Analysis of Spindle-Disk System Vibration for the High-Density Hard Disk Drive of 80GB/Platter (80GB/PLATTER 하드 디스크 드라이브 설계를 위한 스핀들-디스크 시스템 진동의 TMR 기여도 분석)

  • 강성우;한윤식;오동호;황태연;김명업
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.11a
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    • pp.58-64
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    • 2001
  • An investigation of the TMR(Track Misregistration) requirements to achieve the capacity of 80GBytes/Platter in 7200rpm disk drive system is reported. This paper also gives an overview of the PES(Position Error Signal) characteristics in the 57,500TPI disk drive to estimate the required 95,000TPI-system PES. The TMR measured by PES are presented and decomposed in order to identify the portions and their contributions of the spindle-disk system vibration and HSA(Head-Stack-Assembly) system vibration respectively. A comprehensive review on the servo system is also presented to provide the practical limits of the modem servo architecture into TMR budget design. The decomposed PES energy distribution shows that the spindle-disk pack vibration is one of the top-ranking sources of the total TMR budget and its percentage contribution is about 50% considering all the other TMR sources.

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Development of Air Foil Bearing for High Speed Generator (고속 발전기용 Air Foil Bearing 개발)

  • 염병용;박희용;백기영;이영섭;김명섭
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.11a
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    • pp.349-353
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    • 2001
  • An air foil bearing is developed for the high speed generator. The bearing is type of multi-leaf and is stable on 60,000RPM. The vibration level is 12um(p-p) and the highest temperature level is below 100$^{\circ}C$. The dynamic parameter of air foil bearing is acquired by experimental method using exciter. The air foil bearing is also good condition at test of real generator and load condition. The condition of foil is very good after 3,000cycle start-stop test. Therefore the air foil bearing is ideal for high speed, light weight and modem turbo-machinery.

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Development of finite element model updating program (유한요소 모델 개선 프로그램 개발)

  • Wang, S.M.;Ko, C.S.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.1633-1640
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    • 2000
  • The finite element analysis (FEA) is widely used in modem structural dynamics because the performance of structure can be predicted in early stage. However, due to the difficult in determination of various uncertain parameters, it is not be easy to obtain a reliable finite element model. To overcome these difficulties, updating program of FE model is developed by consisting of pretest, correlation and updating. In correlation, it calculates modal assurance criteria, cross orthogonality, mixed orthogonality and coordinate modal assurance criteria. For the model updating, the continuum sensitivity analysis and design optimization tool (DOT) are used. The SENSUP program is developed for model updating to obtain physical parameter sensitivity. The developed program is applied to practical examples such as the base plate of HDD, BLDC spindle motor, and upper housing of induction motor. And the sensor placement for the square plate is compared using several methods.

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Theoretical Determination of Transfer Length in Pretensioned Members Using Thick Cylinder Theory

  • Oh, Byung-Hwan;Kim, Eui-Sung
    • KCI Concrete Journal
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    • v.12 no.2
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    • pp.31-43
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    • 2000
  • The extensive usage of pretensioned prestressed concrete component in modem construe- tion as structural members mandates precise understanding of its mechanism. Especially, an adequate transfer of prestressing force from steel tendons to concrete around the end regions of the member is a critical issue. Due to the importance of the topic, several investigators have formulated equations modeling the transfer bond length based on various bonding mechanism between steel and concrete. However, the existing models are still inadequate in predicting the bond development in pretensioned prestressed concrete members. Therefore, this study presents a model of transfer bond length based on rational theory that can simulate experimental results. The model is developed into solid mechanics based structural analysis computer program. The program is validated by comparing the analysis results with experimental results of bond stress distribution, concrete strain profiles, and transfer length in pretensioned prestressed concrete members. The proposed analytical procedure in this study can be utilized as a useful tool for realistic evaluation of transfer length in pretensioned prestressed concrete members.

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