• Title/Summary/Keyword: continuous method

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Construction of Continuous Bridges in Hi8h-Speed Railway using Precast Span Method (프리캐스트 스팬 공법을 적용한 고속철도 연속교 시공)

  • 김성일;김성호;이원표;윤철수
    • Proceedings of the KSR Conference
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    • 2001.05a
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    • pp.401-407
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    • 2001
  • Out of 412km long Kyung-bu high-speed railway, 302km was designed in tile form of either bridges or tunnels. Most of bridges were designed to be prestressed concrete box girder type. The precast span method was selected because of good quality of bridge section secured by factory manufacturing, fast construction speed, low construction cost with mechanized construction and the safety fur field workers. The precast span method has been mainly utilized in bridges consisted of repeated simple spans. However, we applied the precast span method to continuous bridge for high-speed railway Since it was the first attempt to apply ate precast span method to a continuous bridge for high-speed railway, many design and construction details were studied and implemented in the construction. Design and construction processes of a continuous bridge construction using tile precast span mettled are briefly described in this paper.

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Continuous element method for aeroacoustics' waves in confined ducts

  • Khadimallah, Mohamed A.;Harbaoui, Imene;Casimir, Jean B.;Taieb, Lamjed H.;Hussain, Muzamal;Tounsi, Abdelouahed
    • Advances in nano research
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    • v.13 no.4
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    • pp.341-350
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    • 2022
  • The continuous elements method, also known as the dynamic stiffness method, is effective for solving structural dynamics problems, especially over a large frequency range. Before applying this method to fluid-structure interactions, it is advisable to check its validity for pure acoustics, without considering the different coupling parameters. This paper describes a procedure for taking wave propagation into account in the formulation of a Dynamic Stiffness Matrix. The procedure is presented in the context of the harmonic response of acoustic pressure. This development was validated by comparing the harmonic response calculations performed using the continuous element model with the analytical solution. In addition, this paper illustrates the application of this method to a simple compressible flow problem, since it has been applied solely to structural problems to date.

Servo System Control Using Continuous Time Deadbeat Controller (연속시간 유한정정제어기를 이용한 서보시스템 제어)

  • 김진용;김성은;김성열;이정국;이금원;이준모
    • Proceedings of the Korea Institute of Convergence Signal Processing
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    • 2001.06a
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    • pp.117-120
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    • 2001
  • Deadbeat property is well established in digital control system design, But in continuous time, it can hardly realized for it's asymtotic property. But recently japanese researchers suggested serveral method for continuous time deadbeat property. They use delay elements In polynomials and established for the deadbeat condition. By solving this condition, unknown coefficients in polynomials with delay elements is obtained. In this paper, design method for optimal continuous time deadbeat servo system using 2nd order smooting elementsis studied. Continuous time deadbeat controller is consisted of serial integral compensator and local feedback one in state feedback loop. Determining method for damping rations and natural frequencies of smothing elements is described. By computer simulations, control inputs and system outputs are shown to have desirable property such as smoothness.

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An Efficient PAB-Based Query Indexing for Processing Continuous Queries on Moving Objects

  • Jang, Su-Min;Song, Seok-Il;Yoo, Jae-Soo
    • ETRI Journal
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    • v.29 no.5
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    • pp.691-693
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    • 2007
  • Existing methods to process continuous range queries are not scalable. In particular, as the number of continuous range queries on a large number of moving objects becomes larger, their performance degrades significantly. We propose a novel query indexing method called the projected attribute bit (PAB)-based query index. We project a two-dimensional continuous range query on each axis to get two one-dimensional bit lists. Since the queries are transformed to bit lists and query evaluation is performed by bit operations, the storage cost of indexing and query evaluation time are reduced significantly. Through various experiments, we show that our method outperforms the containment-encoded squares-based indexing method, which is one of the most recently proposed methods.

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Phase Equilibria in Multicomponent Mixtures using Continuous Thermodynamics (연속열역학을 이용한 다성분 혼합물의 상평형)

  • Yong, Pyeong-Soon;Kim, Ki-Chang;Kwon, Yong Jung
    • Journal of Industrial Technology
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    • v.18
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    • pp.267-275
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    • 1998
  • Continuous thermodynamics has been applied for modeling of phase equilibria in multicomponent mixtures, to avoid disadvantages of the pseudo-component and key-component method. In this paper continuous thermodynamic relations formulated by using the Pate-Teja equation of state were adopted for calculations of phase equilibria in natural gas mixtures, crude oil mixtures and mixtures extracted by supercritical $CO_2$ fluids. Calculations of phase equilibria were performed by two procedures ; a moment method coupled with the beta distribution function and a quadrature method combined with Gaussian-Legendre polynomials. Calculated results were compared with experimental data. It was showed that continuous thermodynamic frameworks considered in this paper were well-matched to experimental data.

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A STUDY ON THE PHYSICAL PROPERTIES AND VOLUMETRIC STABILITY OF SR-IVOCAP RESIN SYSTEM (SR-Ivocap resin system의 물리적 특성과 체적 안정성에 관한 연구)

  • Eun, Sung-Sik;Kweon, Hyeog-Sin;Chung, Chae-Heon
    • The Journal of Korean Academy of Prosthodontics
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    • v.36 no.3
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    • pp.453-467
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    • 1998
  • This study helps to clarify conflicting reports by comparing the physical properties and accuracy of complete denture processed by the pack and press technique, continuous- pressure injection technique(SR-Ivocap system) and Mark press technique. The 6 different specimens have been evaluated using the SEM, Impact test, DSC (Differential Scanning Calorimetry) and DMTA (Dynamic Mechanical Thermal Analysis). Each sample was made of SR-Ivocap resin and QC-20 resin by different processing methods. The results were as follows ; 1. As the result of the observation on the fracture surface of resin by use of SEM, sample SR-Ivocap resin cured by continuous pressure injection method showed the most homogeneous structure. This is why molecules in SR-Ivocap resin have no orientation. 2. As the result of the Impact test in order to measure the deformity, fracture energy and impact resistance of resin, the samples with QC-20 acrylic resin and SR-Ivocap resin cured by continuous pressure injection method were exellent. 3. In consequence of measuring ${\alpha}$-glass transition temperature by use of DSC on the basis of temperature change, the glass transition temperatures of sample QC-20 resin cured by pack and press method and sample SR-Ivocap resin cured by continuous pressure injection method were very similar. Thus volumetric stability could not be evaluated only by glass transition temperature. 4. In comparing volumetric stability data by DMTA, the glass transition temperature(Tg) showed $137.88^{\circ}C$ at sample QC-20 resin cured by pack and press method and $139.78^{\circ}C$ at sample SR-Ivocap resin cured by continuous pressure injection method. Therefore sample SR-Ivocap resin cured by continuous pressure injection method seems to be superior to sample QC-20 resin cured by pack and press method in the dimensional stability at high temperature. 5. In comparing storage modulus data by DMTA, the storage modulus of sample SR-Ivocap resin cured by continuous pressure injection method was higher than that of sample QC-20 resin cured by pack and press method. So. sample SR-Ivocap resin cured by continuous pressure injection method seems to be superior to sample QC-20 resin cured by pack and press method in impact strength.

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Study on the Dynamic Analysis of the Continuous System by Digital Modeling (이산화 기법에 의한 연속계의 동적 응답해석에 관한 연구)

  • 이용관;김인수;홍성욱;췌처린
    • Journal of KSNVE
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    • v.7 no.1
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    • pp.135-142
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    • 1997
  • This paper presents a digital modeling technique of the distributed system. The basic idea of the proposed technique is to discretize a continuous system with respect to the spatial coordinates using bilinear method. The response of the discretized system is analyzed by Laplace transform and z-transform. The computational results in torsional shaft and Timoshenko beam using the proposed technique are compared with the exact solutions and the results of finite element method.

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CONVERGENCE OF THE NEWTON METHOD FOR AUBIN CONTINUOUS MAPS

  • Argyros, Ioannis K.
    • East Asian mathematical journal
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    • v.25 no.2
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    • pp.153-157
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    • 2009
  • Motivated by optimization considerations we revisit the work by Dontchev in [7] involving the convergence of Newton's method to a solution of a generalized equation in a Banach space setting. Using the same hypotheses and under the same computational cost we provide a finer convergence analysis for Newton's method by using more precise estimates.

Input Dimension Reduction based on Continuous Word Vector for Deep Neural Network Language Model (Deep Neural Network 언어모델을 위한 Continuous Word Vector 기반의 입력 차원 감소)

  • Kim, Kwang-Ho;Lee, Donghyun;Lim, Minkyu;Kim, Ji-Hwan
    • Phonetics and Speech Sciences
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    • v.7 no.4
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    • pp.3-8
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    • 2015
  • In this paper, we investigate an input dimension reduction method using continuous word vector in deep neural network language model. In the proposed method, continuous word vectors were generated by using Google's Word2Vec from a large training corpus to satisfy distributional hypothesis. 1-of-${\left|V\right|}$ coding discrete word vectors were replaced with their corresponding continuous word vectors. In our implementation, the input dimension was successfully reduced from 20,000 to 600 when a tri-gram language model is used with a vocabulary of 20,000 words. The total amount of time in training was reduced from 30 days to 14 days for Wall Street Journal training corpus (corpus length: 37M words).

Precast Full Span Construction of Continuous PSC Box Girder Bridge for High Speed Railway (고속철도 PSC 박스거더 연속고의 프리캐스트 경간 일괄 가설)

  • Park Jeong Wha;Kim Kwang Soo;Sim Chungwook;Yoon Chul-Soo
    • Proceedings of the KSR Conference
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    • 2004.06a
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    • pp.1168-1173
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    • 2004
  • Bridges and tunnels mainly compose the structural system of Kyung-bu high-speed railway in Korea and the prestressed concrete box girder bridges are applied for the most part of bridge structures. Precast full span construction method was practiced in the construction of many prestressed concrete box girder bridges in Kyung-bu high speed railway for the high quality, great construction speed, low construction cost and construction safety. However, there have been no application of this method in continuous bridges until now. Therefore, a new advanced precast full span construction method is developed using pre-tensioning for precast and post-tensioning in alternating the simple span into a continuous bridge system. since the high-speed railway trains can cause dynamic problems in a continuous bridge. This study shows the structural behavior and the construction process of the new advance method.

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