• 제목/요약/키워드: alignments

검색결과 285건 처리시간 0.023초

곡선구간을 포함한 고가철도의 레일 구조물 상호작용 해석 (Rail Structure Interaction Analysis for the Curved-Elevated Viaducts)

  • 조의경;박성룡
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2005년도 추계학술대회 논문집
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    • pp.376-381
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    • 2005
  • This paper presents the rail structure interaction analysis of the elevated viaducts which contains the curved alignments with smallest radius of 300 metre. The aim of this study is to check the compatibility between the track and the curved structure in order to verify the safety of the continuous welded rail track under service conditions. To perform the rail structure interaction analysis, nonlinear static rail structure interaction calculation is implemented. The bridge structures, the rails and the track behaviour are modelled according to the UIC774-3 and the Eurocode prEN1991-2 recommendations. Criteria in Eurocode prEN1991-2 are investigated to check the compatibility between the track and the structure for the rail structure interaction effects.

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고정밀 장비의 진동허용규제치에 대한 시간 및 주파수 영역에서 나타나는 불일치 문제에 관한 연구 (A Study on the Mismatch of Time and Frequency Domain for Vibration Criteria of Sensitive Equipment)

  • 이홍기;김강부;백재호
    • 반도체디스플레이기술학회지
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    • 제1권1호
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    • pp.1-7
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    • 2002
  • Modem technology depends on the reliability of extremely high precision equipments. In the production of semiconductor wafer, optical and electron microscopes, ion-beam, laser device must maintain their alignments within a sub-micrometer. This equipment requires a vibration free environment to provide its proper function. Therefore, this high technology equipments require very strict environmental vibration criteria because it is used as basic data for the design of building structure and structural dynamics of equipment. In this paper, the new approach is proposed to investigate the mismatch problem of time and frequency domain for vibration criteria of sensitive equipment. The proposed approach is based on a vibration measurement data and a relative transfer function which can be obtained by experiment or analysis.

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Abnormal Temperature Dependence of Tunneling Magnetoresistance for Magnetic Tunnel Junctions

  • Lee, K.I.;Lee, J.H.;Lee, W.Y.;Rhie, K.;Lee, B.C.;Shin, K.H.
    • Journal of Magnetics
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    • 제7권2호
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    • pp.59-62
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    • 2002
  • Magnetic tunnel junctions (MTJs) were fabricated with high bias for plasma oxidation and the effects of annealing on the temperature dependence of tunneling magnetoresistance (TMR) were investigated experimentally. As-grown, TMR increases, peaks around 160 K, and decreases with increasing temperature from 80 K to 300 K. When MTJs are annealed, $T_{max}$, the temperature at which maximum TMR is obtained, decreases as annealing temperature increases to the optimal point. In order to explain this abnormal temperature dependence of TMR, the difference of conductance between parallel and antiparallel alignments of magnetizations as a function of temperature is also analyzed. The shifts of $T_{max}$ due to annealing process are described phenomenologically with spin-dependent transfer rates of electrons tunnel through the barrier.

GPS 반송파 위상변화율을 이용한 GPS/SDINS 결합모델 (GPS/SDINS integration model using GPS carrier phase rate measurements)

  • 박준구
    • 정보통신설비학회논문지
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    • 제4권1호
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    • pp.1-6
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    • 2005
  • As an application of the GPS/SDINS integration for its synergistic results, the alignments of the SDINS utilizing GPS carrier phase rate measurements is introduced. A measurement model of GPS carrier phase rate, which does not require integer ambiguity determination process, is newly derived in order to be adopted with the SDINS in-flight alignment process. For in-flight alignment, the performance of the GPS/SDINS integration method suggested in this paper is analyzed using the covariance analysis.

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러빙배향된 액정셀에 대한 자외선 조사효과 (Effects of UV Irradation on the Alignment of Liquid Crystal)

  • 김영식;김재형
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집
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    • pp.324-327
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    • 2001
  • Liquid crystal alignments on a rubbed polyimide layer were investigated by using optical transmission method. Using this technique, we also studied the pretilt angle of the polymer molecules near the surface of a side-chain polymer layer as a function of the rubbing strength. In particular, we obtained the optical characteristics of liquid crystal orientations and pretilt angles for LC cell photo-aligned by UV as well after rubbing alignment. High pretilt angle of 3.84 degree was obtained on the weekly rubbed polymide layer during UV irradation time of 60min.

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스트랩다운 관성항법 시스템의 운항 중 정렬을 위한 궤적에 따른 가관측성 분석 (The Observability Analysis of SDINS on The Trajectory for The In-Flight Alignments)

  • 박준구;이장규;박찬국;정도형
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 B
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    • pp.1002-1004
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    • 1996
  • In this paper, presented are the results of observability analysis for the vehicle maneuver during In-Flight Alignment of SDINS. The target system for observability analysis is 10th order one. Three trajectories for IFA are considered. To analyze the observability of the time varying system, correlation coefficient is used and to measure the degree of observability of the given system, simulation is carried out using covariance matrix. The results of simulation show that trajectories which are having continuous changes in attitude and acceleration of system is superior to straight trajectory in correcting navigation errors.

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Effect of Bundle Junction Face and Misalignment on the Pressure Drops Across a Randomly Loaded and Aligned 12 Bundles in Candu Fuel Channel

  • H. C. Suk;K. S. Sim;C. H. Chung;Lee, Y. O.
    • Nuclear Engineering and Technology
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    • 제28권3호
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    • pp.280-289
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    • 1996
  • The pressure drop of twelve fuel bundle string in the CANDU-6 fuel channel is equal to the sum of the eleven junction pressure losses, the bundle string entrance and exit pressure losses, the skin friction pressure loss, and other appendage pressure losses, where the junction loss is dependent on the bundle end faces and angular alignments of the junctions. The results of the single junction pressure drop tests in a short rig show that the most probable pressure drop of the eleven junctions was analytically equal to the eleven times of average pressure drop of all the possible single junction pressure drops, and also that the largest and smallest junction pressure drops across the eleven junctions probably occurred only with BA and BB type junctions, respectively, where A and B denote the bundle end sides with an end-plates on which a company monogram is stamped and unstamped, respectively.

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고정밀 장비의 진동허용규제치에 대한 시간 및 주파수 영역에서 나타나는 불일치 문제에 관한 연구 (A Study on the Mismatch of Time and Frequency Domain for Vibration Criteria of Sensitive Equipment)

  • 이홍기;김강부;전종균;백재호
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2001년도 추계학술대회논문집 II
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    • pp.1376-1383
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    • 2001
  • Modem technology depends on the reliability of extremely high technology equipments. In the production of semiconductor wafer, optical and electron microscopes, ion-beam, laser device must maintain their alignments within a sub-micrometer. This equipment requires a vibration free environment to provide its proper function. Especially, lithography and inspection devices, which have sub-nanometer class high accuracy and resolution, have come to necessity for producing more improved giga and tera class semiconductor wafers. This high technology equipments require very strict environmental vibration standard, vibration criteria, in proportion to the accuracy of the manufacturing, inspecting devices. The vibration criteria of high sensitive equipment should be represented in the form of 'exactness' and 'accuracy', because this is used as basic data for the design of building structure and structural dynamics of equipment. This paper deals with the properties of time and frequency domain in order to obtain more improved vibration criteria for high sensitive equipment.

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주행경제를 위한 드라이빙 시뮬레이터 모듈 연구 (Development of driving simulator modules for driving safely)

  • 정성학
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2008년도 추계학술대회
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    • pp.569-578
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    • 2008
  • The aim of this study is to propose economical safety driving speed index which those are geometric road status; examine the levels of which those cost-benefit of driving fuel expenditure; are search road safety design and operational technology for driving simulators. For the objective, we analyzed the current status of driving fuel expenditure and driving scenarios by the road alignments, and reviewed driving and technical specifications by the geometric types of road according to the implementation, and extended completion. Throughout the result of this study, diverse related driving information provision service, efficiently driving system is expected to be implemented in the national highway design system.

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번역지원 시스템을 위한 유사 예문 검색 (Searching Similar Example Sentences for the Computer-Aided Translation System)

  • 김동주;김한우
    • 한국컴퓨터정보학회지
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    • 제14권1호
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    • pp.197-204
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    • 2006
  • 본 논문에서는 번역 지원 시스템을 위한 유사문장 검색 알고리즘을 제안한다. 이 알고리즘은 Needleman- Wunsch 알고리즘에 기반을 두고 있으며, 단어의 비교를 위해 단어의 표면어 정보, 표제어 정보, 품사 정보 계층으로 된 다층 정보의 융합을 통해 유사도를 계산하고 정렬을 수행하게 된다. 제안하는 알고리즘은 전기통신 분야의 문장 데이터에 대해 매우 우수한 검색 정확률을 보였다.

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