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Zonghua Zhang
The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 33-34, 2011, DOI:10.3970/icces.2011.018.033
Abstract Optical full-field fringe projection techniques have been widely studied in academia and applied to many actual industrial fields of automatic inspection, reverse engineering, heritage protection, cosmetic surgery, and so on. With the advent of color CCD cameras and Digital Micromirror Device (DMD) based color Digital Light Processing (DLP) projectors, their major red, green and blue channels have been used as a carrier to code fringe patterns. Since three fringe patterns can be simultaneously projected and captured by a color image, the acquisition time reduces to 1/3 of the value by projecting only gray fringe patterns. This talk introduces two kinds… More >

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618

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Xiaoping Zhang
The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 35-36, 2011, DOI:10.3970/icces.2011.018.035
Abstract In this paper, we first discuss the midpoint rule for evaluating hypersingular integrals with the kernel \qopname \relax osin-2(x-s)/2 defined on a circle, and the key point is placed on its pointwise superconvergence phenomenon. We show that this phenomenon occurs when the singular point s is located at the midpoint of each subinterval and obtain the corresponding supercovergence analysis. Then we apply the rule to construct a collocation scheme for solving the relevant hypersingular integral equation, by choosing the midpoints as the collocation points. It's interesting that the inverse of coefficient matrix for the resulting linear system has an explicit… More >

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567

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Ryoichi Yamamoto
The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 37-38, 2011, DOI:10.3970/icces.2011.018.037
Abstract We developed a unique method for direct numerical simulations (DNS) of dense colloidal dispersions [3, 5]. This method, called the smoothed profile method (SPM), enables us to compute the time evolutions of colloidal particles, ions, and host fluids simultaneously by solving Newton, advection-diffusion, and Navier-Stokes equations so that the electro- hydrodynamic couplings can be fully taken into account. We have applied the SPM successfully for simulating dynamics of various particle dispersions, including colloids in liquid crystals [1, 2], electrophoresis of charged colloids [4, 5], particle diffusion in fluids [7, 8], dispersion rheology [9, 11], tumbling chain in shear flow [10],… More >

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631

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Song Zhang, Yajun Wang, Laura Ekstrand, Ying Xu, Yuanzheng Gong
The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 39-40, 2011, DOI:10.3970/icces.2011.018.039
Abstract High-speed, high-resolution 3-D shape measurement has become increasingly important, with broad applications including medicine, homeland security, and entertainment. Techniques such as structured light, stereovision, and LIDAR have led the way in this field. In recent years, we have made some progress, developing an unprecedented 60 Hz system utilizing a digital fringe projection and phase-shifting method and simultaneously achieving 40 Hz 3-D shape acquisition, reconstruction, and display. However, a conventional digital fringe projection system requires the computer to generate sinusoidal fringe patterns to be sent to the projector. Because 8 bits are usually needed to represent high-contrast sinusoidal patterns, the data-throughput… More >

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629

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Jiancheng Xu, Yong Li
The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 41-42, 2011, DOI:10.3970/icces.2011.018.041
Abstract We propose a non-iterative approach to extract the unknown phase shift in phase shifting interferometry without the assumption of equal distribution of measured phase in [0,2I?]. According to the histogram of the phase difference between two adjacent frames, the phase shift can be accurately extracted by finding the bin of histogram with the highest frequency. The main factors that influence the accuracy of the proposed method are analyzed and discussed, such as the random noise, the quantization bit of CCD, the number of fringe patterns used and the bin width of histogram. It shows that the average phase-shift extraction error… More >

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566

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S.J. Zhu, Q.H Zeng, J.J Lou, Q.W He
The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 43-44, 2011, DOI:10.3970/icces.2011.018.043
Abstract Line spectra are the most visible signs of the ships' radiated noise spectrum. The potential of chaotifying vibration isolation systems to reduce line spectra and improve its capability of concealment have been recently reported. Basically, as the existing isolation system design is based on linear theory, it is difficult to produce the nonlinear chaotic motion; and if the vibration isolation system(VIS) is designed directly using the nonlinear theory, it is also difficult to produce the chaotic motion because of the difficulties in accurate calculation of vibration isolation device parameters. In this paper, a controller design method is put forward using… More >

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615

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Yasuhiro Kajima, Miyabi Hiyama, Shuji Ogata
The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 45-46, 2011, DOI:10.3970/icces.2011.018.045
Abstract There has been increased interest to understand through computer simulation the dynamics of micro-droplets; for example, the coalescence and/or disruption of water droplets as a fundamental process of the cloud formation for the earth climate estimation, the formation and size-controlling mechanism of the ink-droplet for advanced ink-jet printer. Since long-time simulations of such water droplets at atomistic scale are required, we often choose the rigid-body type inter-atomic potential as the TIP4P. In the present paper, we propose the improved angular-momentum Verlet (IAMV) method for the time evolution of the rigid molecules, by enforcing complete time-reversibility to the AMV method [1].… More >

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617

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Philippe G. CIARLET
The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 47-48, 2011, DOI:10.3970/icces.2011.018.047
Abstract Intrinsic methods in elasticity have been introduced in a landmark series of papers by Wei-Zhang Chien in 1944. During the last two decades, Professor Wojciech Pietraszkiewicz and his group have achieved major advances in their analysis from the mechanical and engineering viewpoints, as well as in their actual implementation.
However, it was only in 2004 that their mathematical analysis began to be carried out in earnest, first for three-dimensional elasticity and more recently for elastic shells, by the author and his group.
This presentation will briefly review and discuss various problems as yet unresolved in this approach.
In… More >

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537

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H. Watanabe, M. Suzuki, N. Ito
The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 49-50, 2011, DOI:10.3970/icces.2011.018.049
Abstract Gas-liquid two-phase flow is a system containing gas and liquid phase. While the gas-liquid two-phase flow is important for applications such as power plants and pump cavitations, it is difficult to study gas-liquid multiphase flow theoretically or numerically since it is multi-scale and multi-physics system involving not only flow but also phase transitions. In order to overcome the difficulties, we study the two-phase flow with full particle simulations. In the full-particle simulation, phase boundaries create and annihilate spontaneously, and therefore, multi-physics phenomena are naturally simulated. We developed a parallel molecular dynamics (MD) simulation code which is scalable up to ten… More >

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581

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Alexander G. TYAPIN
The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 51-52, 2011, DOI:10.3970/icces.2011.018.051
Abstract The author extends the previously proposed combined asymptotic method of seismic SSI analysis for the multiply-supported structures. One of the examples of such structures in Nuclear Power Plant is the transportation portal linked to the reactor building by horizontal beams.
The first step still is (like for single-base structure) to develop the dynamic stiffness matrices condensed to the rigid contact surfaces in the frequency domain separately for the soil foundation and for the structure.
For the soil foundation special computer codes like SASSI are used for this purpose. Seismic forces acting to the fixed basements from the soil are… More >

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615

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Yu Niu, Feng Xu^*, Xiaofang Hu, Yongcun Li, Hongyan Qu, Jing Zhao, Zhong Zhang
The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 53-54, 2011, DOI:10.3970/icces.2011.018.053
Abstract In this work, the influence of the second phase fine powders on solid state sintering process was in situ investigated by synchrotron radiation X-ray computed tomography (SR-CT) technique. Microstructure evolution of the pure SiO2 powders and SiO2 powders mixed with Si3N4 fine powders during sintering is observed respectively from the SR-CT reconstructed images.
Sintering process, as the final and the most crucial step for the preparation of various ceramic materials, will inevitably affect the microstructure and properties of the material. The inclusions with different kinds or particle size may promote or hinder the sintering process. Mixed powder system is widely… More >

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590

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Luobin Wang, Feng Xu^*, Xiaofang Hu, Hongyan Qu, Hong Miao, Zhong Zhang
The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 55-56, 2011, DOI:10.3970/icces.2011.018.055
Abstract Recent studies have indicated that mechanical performance of the short fiber-reinforced polymers composites not only depends on matrix type, fiber type, fiber weight fraction, fiber orientation, fiber dispersion etc. but fiber-matrix interface and matrix morphology are also of paramount importance. Many scholars have studied on effects of matrix and interface modification on the mechanical behavior of short carbon fiber reinforced epoxy composite. However, there is little work focused on the in situ observation of fracture process of fiber/epoxy composites. And it is difficult to know about crack and crack propagation in the sample without direct observations of fiber-matrix interface when… More >

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825

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632

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Shiqin He, Pengfei Li, Feng Shang
The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 57-58, 2011, DOI:10.3970/icces.2011.018.057
Abstract A three-dimensional finite-element (FE) analytical approach for the simulation of Shear property of steel-concrete composite beam is presents in this paper. To simulate the interfacial behavior between the steel girders and concrete slabs, an interface-slip model which has been better used in analyzing the flexural property of composite beams is applied in the simulation. Both simple-supported beam experiment at positive bending zone and negative bending moment zone in literatures are simulated respectively. The load-deflection and the slip rule between the steel girders and concrete slabs as well as the crack pattern and the contour at the ultimate load are analyzed.… More >

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545

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Y. Gan, Z. Chen, S. Montgomery-Smith
The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 59-60, 2011, DOI:10.3970/icces.2011.018.059
Abstract The material point method (MPM), which is an extension from computational fluid dynamics (CFD) to computational solid dynamics (CSD), is improved for the coupled CFD and CSD simulation of the zona failure response in piezo-assisted intracytoplasmic sperm injection (piezo-ICSI). To evaluate the stresses at any zona material point, a plane stress assumption is made in the local tangent plane of the membrane point, and a simple procedure is proposed to find the effective point connectivity for the orientation of the local tangent plane. With an iterative algorithm in each time step, the original MPM is improved to better simulate fluid… More >

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538

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Zhigang Guo, Zhi Sun
The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 61-62, 2011, DOI:10.3970/icces.2011.018.061
Abstract An efficient approach to identify multiple cracks in a slender beam using the frequency response function data is presented. It is formulated in a general form from the dynamic stiffness equation of motion for a structure and then applied to a slender beam. The cracks are modeled by rotational springs and the frequency response function is computed based on a spectral element model by the spectral finite element. The procedure gives a linear relationship explicitly between the changes of the measured frequency response function and crack parameters. The inverse problem is solved iteratively for the depths and locations of the… More >

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832

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578

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Jianglin Xu, Zhi Sun
The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.2, pp. 63-64, 2011, DOI:10.3970/icces.2011.018.063
Abstract The measurement of residue prestress force is one main issue for condition and performance assessment of prestressed concrete beam bridge. This paper proposes a vibration based parameter estimation technique for this purpose. Under given form external excitation, beam velocity responses at multiple points are collected firstly. The prestress force of the beam is then identified based on the minimization of the least square difference between the measured response and the baseline response. A numerical study on a beam of variant length, subjected to a constant prestress force with variant eccentricity, is conducted to show the effect of prestress force and… More >

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