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Terry Yuan-Fang Chen, Jian-Siang Chen
The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 33-34, 2011, DOI:10.3970/icces.2011.020.033
Abstract Chemical mechanical planarization (CMP) process flattens the wafer by polishing it against a rotating pad. During the polishing process, a diamond coated grinding wheel must be frequently employed to remove the accumulated debris lest the polishing surface glazes. To assure the flatness of polished wafers during the CMP process, the surface warpage of the diamond grid dresser surface must be small enough. In this study, phase-shifted shadow moirAC method was employed to measure the surface profile of diamond grinding wheel, and the warpage was determined by LSM (lease-squares surface method). Since the impinging light may either be reflect directly or… More >

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693

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San-Qiang Shi
The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 35-36, 2011, DOI:10.3970/icces.2011.020.035
Abstract Zirconium and its alloys are key structural materials used in the nuclear power industry. In service, these metals are susceptible to a slow corrosion process that leads to a gradual pickup of hydrogen impurities from the environment. It is well known that hydrogen impurity will be attracted to stress concentrators such as notch and crack tips. At a certain hydrogen level, a complicated pattern of hydride precipitates can develop around these stress concentrators. Because of the brittleness of these hydrides, the original strength of the alloys can be reduced by orders of magnitude, and the fracture through these hydrides may… More >

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754

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ABSTRACT

Qiao Hua, Wei-Qiu Chen, Qingda Yang
The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 37-38, 2011, DOI:10.3970/icces.2011.020.037
Abstract Predicting arbitrary delamination in laminar composites remains a significant numerical challenge in composite engineering [1,2]. Currently the major technical difficulty is to predict accurately when (at what load level) and where (in which interface) should delamination occur within a pristine composite laminates upon loading. Linear-elastic-fracture-mechanics (LEFM) based methods have limits because 1) requirement of known or assumed initial flaws of finite size, and 2) unknown crack-tip singularity functions for interfaces that bond non-orthogonal plies. Numerical tools based on LEFM such as virtual crack closure technique (VCCT) suffer from serious numerical problems including numerical instability and robustness.
Cohesive-zone-models (CZM) based simulation… More >

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730

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I. S. Raju
The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 39-40, 2011, DOI:10.3970/icces.2011.020.039
Abstract Lifetime Achievement Award

Dr. Ivatury S. Raju

NASA Engineering and Safety Center

NASA Langley Research Center, USA

for his contributions to the Structural Integrity & Durability More >

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737

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Arunachalam M. Rajendran
The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 41-42, 2011, DOI:10.3970/icces.2011.020.041
Abstract Lifetime Achievement Award

Professor Arunachalam M. Rajendran

Department of Mechanical Engineering

University of Mississippi, USA

for his contributions to the Impact Behavior of Advanced Materials & Structures More >

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942

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661

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Weichung Yeih, Chia-Min Fan, Zen-Chin Chang,Chen-Yu Ku
The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 43-44, 2011, DOI:10.3970/icces.2011.020.043
Abstract In this paper, the Cauchy problem of the nonlinear steady-state heat conduction is solved by using the polynomial expansion method and the exponentially convergent scalar homotopy method (ECSHA). The nonlinearity involves the thermal dependent conductivity and mixed boundary conditions having radiation term. Unlike the regular boundary conditions, Cauchy data are given on part of the boundary and a sub-boundary without any information exists in the formulation. We assume that the solution for a two-dimensional problem can be expanded by polynomials as: where T is the temperature distribution, np is the maximum order of polynomial expansion, x and y are Cartesian… More >

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952

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728

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A.Y.Chen, J. Lu
The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 45-46, 2011, DOI:10.3970/icces.2011.020.045
Abstract The structural reliability of many brittle materials such as nanomaterials relies on the occurrence of intergranular, as opposed to transgranular, fracture in order to induce toughening by crack bridging. The current work examines the role of interface strength and grain size distribution in promoting intergranular fracture in order to maintain high toughening. A layered nanostructural 304SS sheet characterized by periodic distribution of nanocrystalline layers and micron-grained layers with graded grain size evolution has exhibited exceptional properties. The in situ SEM observations illustrate that an intergranular path and the consequent interface bridging process can be partitioned into five distinct regimes, namely:… More >

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979

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695

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Hongyang Li, Cheng Chen, WeiWei Li, Yanjing Zhang, Xiaopeng Liu, Yandong Wang
The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 47-48, 2011, DOI:10.3970/icces.2011.020.047
Abstract Large numbers of micro lattice plastic deformation of grains set up the macro plastic deformation of polycrystal metallic materials under different macro boundary condition. And the macro homogeneous deformation is in fact the statistical result of micro anisotropic lattice plastic flow. Both of the macro and micro deformation were influenced by intrinsic initial stress, which was intrinsic in the component from micro scale impurity to macro scale non-uniform deformation. In this paper, focused on the engineering application and further damage evaluation, effect of macro initial stress on the macro and micro plasticity deformation of sample under uniaxial tension was discussed… More >

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931

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657

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Yohei Inoue, Taishi Nakamura, Shuji Ogata, Ryo Kobayashi, Toshiyuki Gotoh
The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 49-50, 2011, DOI:10.3970/icces.2011.020.049
Abstract No proper simulation method exists in between the molecular simulation method at nanometer scale using the first principles or empirical inter-molecular interaction and the continuum simulation method at micrometer-plus scale. The nanotechnology deals principally with those systems whose characteristic scales reside in such a scale-gap. Considering this, we develop a sequential scale-up scheme starting from the atomistic up to micrometer-plus scales. In the present paper we take, as an example, the system of graphenes that may or may not be fluttering in airflow, and apply to it our sequential scale-up scheme to see its capability.

The graphene is unique… More >

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701

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Lin Yifeng, Zhu Hehua, Cai Yongcang
The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 51-52, 2011, DOI:10.3970/icces.2011.020.051
Abstract Shield tunnel linings compose of segments , bolts, liners, et.al., which are quite different in geometry and mechanics. Traditional beam-spring joint model and shell-spring joint model is hard to simulate accurately the detailed characteristic. Classical three-dimensional FEM may cause serious mesh-generation difficulty and expensive calculation cost. Based on generalized finite element method and characteristics of shield tunnel, a three-dimensional shield tunnel structure model is established. In the proposed model a sixteen-node solid-shell generalized FE is devised and employed to simulate segments. Joints between segments or rings are modeled with a surface to surface contact generalized FE which comprise hidden-bolts and… More >

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949

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668

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I-Yao CHAN, Chein-Shan Liu, Weichung Yeih
The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 53-54, 2011, DOI:10.3970/icces.2011.020.053
Abstract In this study, we adopt the fictitious time integration method to treat the image reconstruction problem. The distorted image is considered as a result of diffused data from the initial perfect image by using a nonlinear diffusion equation. The image reconstruction problem then becomes an inverse problem by using the data in the final time to recover the data in the initial time. This inverse problem is known as the backward in time nonlinear diffusion problem which is highly ill-posed. We propose to use the fictitious time integration method to tackle this highly ill-posed image reconstruction problem and it is… More >

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809

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Vijay Kumar Gupta
The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 55-56, 2011, DOI:10.3970/icces.2011.020.055
Abstract Various applications of piezoelectric actuators have been explored over the years. One such application is use of piezoelectric actuators for shape control of structures. In this paper, steering of parabolic antenna by deforming the antenna surface using piezoelectric actuators has been explored. Optimization based on Genetic Algorithm is carried out to find out optimum location, length and applied electric field to the piezoelectric actuators to achieve desired steering of antenna. Constraints are included in the objective function using penalty approach. Shell finite element model is used to determine deformations induced by the actuators. As the wavelength is sufficiently smaller than… More >

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988

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821

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Zhenxing Hu, Huimin Xie, Jian Lu
The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 57-59, 2011, DOI:10.3970/icces.2011.020.057
Abstract Residual stress plays an important role in structural and material manufacturing. Measurement techniques of residual stress can be neatly divided into destructive and non-destructive ones. The destructive techniques are dependent on inferring the original stress from the displacement incurred by completely or partially relieving the stress by removing material. The hole drilling method for residual stress measurement is a destructive method and was first introduced in the 1930s by Mathar. In recent years, the hole drilling method for evaluating residual deformation has been implemented with optical method such as holographic interferometry, electronic speckle pattern interferometry, digital image correlation (DIC), and… More >

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851

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Zheng Yi Wu
The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 60-62, 2011, DOI:10.3970/icces.2011.020.060
Abstract Infrastructure system analysis is a computation-intensive task. Equipped with the software tools, engineers are able to analyze a handful of alternative solutions, but often end up with a workable alternative far from the optimized solution. Effectively optimizing an infrastructure system is a challenging task. Undertaking such a task requires not only well-developed optimization software tools, but also powerful computing facilities. Therefore, infrastructure system optimization is highly desirable to be conducted on cloud.
Infrastructure system optimization is usually an implicit and nonlinear programming problem. The problem has to be carefully formulated in the way that classic mathematic programming can be applied… More >

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926

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894

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Dehao Yu
The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 63-64, 2011, DOI:10.3970/icces.2011.020.063
Abstract In many fields of scientific and engineering computing the Artificial Boundary Method has been widely applied to solve boundary value problems of partial differential equations, especially it is a very important method for solving problems on unbounded domains. This method is first suggested by K. Feng and D. Yu, called the natural boundary element method, and then also called DtN method by J.B. Keller and D. Givoli. The exact artificial boundary condition is the natural boundary integral equation on the artificial boundary, that is just the Dirichlet to Neumann mapping.

The natural boundary integral equation is hypersingular integral equation.… More >

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932

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785

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Ye-Shuang Xu, Shui-Long Shen, Jin-Chun Chai, Zhen-Shun Hong
The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 65-66, 2011, DOI:10.3970/icces.2011.020.065
Abstract With the process of urbanization, a large amount of infrastructures, e.g. metro tunnels, underground path, and building basement, is constructed in underground along coastal mega-cities, e.g. Shanghai, Tianjin, and Guangzhou etc. The existence of underground in aquifers within the urban region obstructs the behavior of seepage and results in the raise of groundwater level at the upper side and drawdown of groundwater level at the lower side of the structure. Therefore, rebound at the upper side and settlement at the lower side of underground structures may occur due to consolidation in long-term and redistribution of land subsidence in urban area… More >

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803