• Title/Summary/Keyword: Analytical calculation

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Form-finding analysis of suspension bridges using an explicit Iterative approach

  • Cao, Hongyou;Zhou, Yun-Lai;Chen, Zhijun;Wahab, Magd Abdel
    • Structural Engineering and Mechanics
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    • v.62 no.1
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    • pp.85-95
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    • 2017
  • This paper presents an explicit analytical iteration method for form-finding analysis of suspension bridges. By extending the conventional analytical form-finding method predicated on the elastic catenary theory, two nonlinear governing equations are derived for calculating the accurate unstrained lengths of the entire cable systems both the main cable and the hangers. And for the gradient-based iteration method, the derivation of explicit calculation for the Jacobian matrix while solving the nonlinear governing equation enhances the computational efficiency. The results from sensitivity analysis show well performance of the explicit Jacobian matrix compared with the traditional finite difference method. According to two numerical examples of long span suspension bridges studied, the proposed method is also compared with those reported approaches or the fundamental criterions in suspension bridge structural analysis, which eventually confirms the accuracy and efficiency of the proposed approach.

Estimation of Loads on Tunnel Lining Based on Case Studies (사례연구를 통한 터널 하중의 예측)

  • 김학준
    • The Journal of Engineering Geology
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    • v.7 no.3
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    • pp.207-216
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    • 1997
  • Estimation of loads on tunnel lining is one of the major issues to be addressed in the design of a tunnel. The existing analytical methods do not consider important details of construction and the variation of geology along the tunnel axis. The measured loads obtained from several sanitary and subway tunnels in Edmonton, Alberta, Canada, are compared with the lining loads calculated using the existing analytical methods. However, the existing methods are determined to be not fully satisfactory for the estimation of lining loads. To account for face and heading effects occurring prior to lining installation, the stress reduction factor determined using Eisenstein and Negro's method is used coupled with an analytical solution for calculation of lining loads.

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Force Characteristic Analysis of Linear Motor to Reduce Manufacturing Error in A Linear Motion Machine Tool (선형 운동 공작기계의 가공오차 저감을 위한 리니어 모터의 힘 특성 해석)

  • Cho, Han-Wook;Han, Cheol;Choi, Jang-Young;Choi, Sang-Gyu;Park, Cheol-Ho;Jang, Seok-Myeong
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.1081-1082
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    • 2011
  • In order to predict the accuracy of the linear motion machine tools, the force characteristics such as the detent force, the attraction force and the moment are estimated by analytical method or FEM. In this paper, we proposed the analytical calculation process for the force characteristics of a linear motor. The analytical results are good agreement with FEM one. They could be used for the precision prediction simulator with the information of linear bearings, encoders, etc.

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An Analytical Calculation of the Transport of the Solute Dumped in a Homogeneous Open Sea with Mean and Oscillatory Flows

  • Lee Ho Jin;Jung Kyung Tae
    • Fisheries and Aquatic Sciences
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    • v.7 no.2
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    • pp.90-95
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    • 2004
  • An analytical model for predicting the convection-diffusion of solute dumped in a homogeneous open sea of constant water depth has been developed in a time-integral form. The model incorporates spatially uniform, uni-directional, mean and oscillatory currents for horizontal convection, the settling velocity for the vertical convection, and the anisotropic turbulent diffusion. Two transformations were introduced to reduce the convection-diffusion equation to the Fickian type diffusion equation, and then the Galerkin method was then applied via the expansion of eigenfunctions over the water column derived from the Sturm-Liouville problem. A series of calculations has been performed to demonstrate the applicability of the model.

Calcuation of Stress Free Surface Profile of Stock in Red Rolling(I) (선재 압연의 소재 자유표면 형상 계산(I))

  • 이영석;최상우;유선준;주웅용
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1999.08a
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    • pp.78-87
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    • 1999
  • A mathematical model for the stress free surface profile in Over-Round and Round-Oval grove rolling, which can be used effectively in the calculation of pass area, is presented. The new model has generality, simplicity and accuracy for practical usage. The stress free surface profile of an outgoing stock can be modeled when the maximum spread of it known a priori. The equation for the stress free surface profile is formulated from the linear interpolation of the radius of curvature of an incoming stock and that of roll groove to the axis direction. In developing the analytical model, the effect of rolling temperature and friction between roll and work piece(stock) were not considered since the geometry of roll groove and the incoming work piece were assumed a dominant factor which decides the stress free surface profile of the outgoing stock. A simulation with the analytical model developed also has been carried out to demonstrate the stress free surface profile of the outgoing stock.

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Calculation of Distributed Magnetic Flux Density under the Stator-Turn Fault Condition

  • Kim, Kyung-Tae;Hur, Jin;Kim, Byeong-Woo
    • Journal of Power Electronics
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    • v.13 no.4
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    • pp.552-557
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    • 2013
  • This paper proposed an analytical model for the distributed magnetic field analysis of interior permanent magnet-type blush-less direct current motors under the stator-turn fault condition using the winding function theory. Stator-turn faults cause significant changes in electric and magnetic characteristic. Therefore, many studies on stator-turn faults have been performed by simulation of the finite element method because of its non-linear characteristic. However, this is difficult to apply to on-line fault detection systems because the processing time of the finite element method is very long. Fault-tolerant control systems require diagnostic methods that have simple processing systems and can produce accurate information. Thus analytical modeling of a stator-turn fault has been performed using the winding function theory, and the distributed magnetic characteristics have been analyzed under the fault condition. The proposed analytical model was verified using the finite element method.

A comparison of the transmission losses of two-dimensional dissipative silencers predicted by analytical method and BEM (이론적 해 및 경계요소법에 의한 2차원 흡음형 소음기의 전달 손실치 예측 비교)

  • 김회전;이정권;정지훈
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.05a
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    • pp.1001-1004
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    • 2002
  • Accurate prediction of the transmission loss of dissipative silencers has been considered difficult due to the ambiguity and complexity in the physical properties of sound absorbing materials. Additional difficulty lies in the fact that the analytical calculation of the propagation constant is unknown yet. In this paper. as a first step toward obtaining the Propagation constant and thus predicting the transmission loss, an approximation equation stemming from the wave analysis in the lined interior has been derived. Such an analytical solution and numerical solution using the boundary element method are compared for a two-dimensional simple dissipative silencer under the assumption of the locally reacting sound absorbent.

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Analytical criteria for fuel fragmentation and burst FGR during a LOCA

  • Khvostov, G.
    • Nuclear Engineering and Technology
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    • v.52 no.10
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    • pp.2402-2409
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    • 2020
  • Analytical criteria for the onset of fuel fragmentation and Burst Fission Gas Release in fuel rods with ballooned claddings are formulated. On that basis, the GRSW-A model integrated with a fuel behaviour code is updated. After modification, the updated code is successfully applied to simulation of the Halden LOCA test IFA-650.12. Specifically, the calculation with Burst Fission Gas Release during the test resulted in prediction of cladding failure, whereas it could not be predicted at the test planning, before new models were implemented. A good agreement of the current model with experimental data for transient Fission Gas Release in the tests IFA-650.12 and IFA-650.14 is shown, as well.

The calculation of inductance profile for linear switched reluctance motor by analytical method (해석적 방법에 의한 리니어 스위치드 릴럭턴스 전동기의 인덕턴스 프로파일 산정)

  • Jang, Seok-Myeong;Park, Ji-Hoon;Choi, Jang-Young;Sung, Ho-Kyung
    • Proceedings of the KIEE Conference
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    • 2005.10c
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    • pp.138-140
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    • 2005
  • This paper deals with inductance profile of linear switched reluctance motor. Inductance profile of LSRM calculate at align and unalign position using analytical method. Analytical method of this paper used space harmonics method, Also, analysis result compares with data that is derived through an experiment, and proved validity.

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Analytical Investigation on Fundamental Electrical Characteristics of Large Air-gap Superconducting Synchronous Machine

  • Yazdanian, M.;Elhaminia, P.;Zolghadri, M.R.;Fardmanesh, M.
    • Journal of Magnetics
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    • v.18 no.3
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    • pp.260-267
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    • 2013
  • In this paper a general 2-D model of a large air-gap synchronous machine either with non-magnetic or magnetic core rotor is investigated and electrical characteristics of the machine are analytically calculated. Considering the general model, analytical equations for magnetic field density in different regions of the large air-gap machine are calculated. In addition, self and mutual inductances in the proposed model of the machine have been developed, which are the most important parameters in the electromagnetic design and transient analysis of synchronous machines. Finite element simulation has also been performed to verify the obtained results from the equations. Analytical results show good agreement with FEM results.