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Mingchao Cai, Chun Yang, Mehmet H. Kural, Richard Bach, David Muccigrosso, Deshan Yang, Jie Zheng, Kristen L. Billiar, Dalin Tang
The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 97-104, 2011, DOI:10.3970/icces.2011.019.097
Abstract Image-based computational modeling has been introduced for vulnerable atherosclerotic plaques to identify critical mechanical conditions which may be used for better risk assessment and rupture predictions. In vivo patient-specific coronary plaque models are lagging due to limitations on non-invasive image resolution, flow data, and vessel material properties. We propose a procedure where intravascular ultrasound (IVUS) imaging, biaxial mechanical testing and computational modeling are combined together to acquire better and more complete plaque data and make more accurate plaque vulnerability assessment and predictions. More >

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798

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Jiahui Pan, Ken Chiavone, Neil Hubble, Ryan Curry
The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 105-106, 2011, DOI:10.3970/icces.2011.019.105
Abstract Recently a number of changes have occurred in electronic packaging, such as increased contact density in both packages and substrates, high reflow temperature due to Pb-free conversion, new materials, new package configurations and new fabrication processes. All these trends demand tighter mechanical tolerances and increase the challenges in modern electronic assembly. Consequently surface flatness plays a more important role in the design and manufacturing process. Warpage introduced by dissimilar CTE (Coefficient of Thermal Expansion) can cause die cracking, solder joint opens, and solder joint cracking. Characterization of the thermally-induced warpage is proving to have significant value in improving manufacturing yield… More >

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985

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735

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Yukitoshi OTANI, Fumio KOBAYASHI, Yasuhiro MIZUTANI, Manabu Harada, Toru YOSHIZAWA
The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 107-108, 2011, DOI:10.3970/icces.2011.019.107
Abstract A uni-axial three dimensional surface measurement by a liquid crystal digital shifter( LCDC) is proposed using a telecentric optical system. Distance information can be determined by measuring the contrast in the projected grating pattern. The magnification of the object image captured by a CCD camera is adjusted constant by changing the focus distance. A shadow less measurement of the object's area is archived by using a uni-axial system. The liquid crystal digital shifter is a powerful tool to make arbitrary intensity and frequency distribution. Surface profiles of some mechanical parts were measured to demonstrate this method. More >

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1131

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801

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M.S. Raju & Dan Bulzan
The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 109-110, 2011, DOI:10.3970/icces.2011.019.109
Abstract The paper presents the results from a validation study undertaken as a part of the NASA's fundamental aeronautics initiative on high altitude emissions in order to assess the accuracy of several atomization models used in both sub-cooled and superheat spray calculations. As a part of this investigation we have undertaken the validation based on four different cases to investigate the spray charactereristics of (1) a ashing jet generated by the sudden release of pressurized R134A from cylindrical nozzle, (2) a liquid jet atomizing in a subsonic cross ow, (3) a Parker-Hannin pressure swirl atomizer, and (4) a single-element LDI (Lean… More >

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1125

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812

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N.A. Dumont, D. Huaman
The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 111-112, 2011, DOI:10.3970/icces.2011.019.111
Abstract This paper proposes a hybrid finite element formulation of the strain gradient elasticity that provides a natural conceptual framework to properly deal with the interelement compatibility of normal displacement gradients and the equilibrium of non-classical boundary forces. It is based on developments firstly proposed by Mindlin and further elaborated by Aifantis. Consistency is assessed - in the full manuscript version - by means of several generalized patch tests. More >

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1118

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870

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V.K. Tewary
The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 113-114, 2011, DOI:10.3970/icces.2011.019.113
Abstract Interfacial region between two nanomaterials can be treated as a separate material since its atomistic structure and characteristics are different than the two materials on its either side. The mechanical as well as electronic properties of composite materials are sensitive to the interfaces. For industrial application of the nanomaterial systems, it is vital to model and measure the discrete atomistic locations in the interface during operating conditions. As the dimensions of nanomaterial systems shrink, the role of interfaces become increasingly important. Because of its nanothickness, the conventional characterization and design parameters like elastic constants, stress and strains are not reliable… More >

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1125

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810

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Takahide Nakamura
The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 115-116, 2011, DOI:10.3970/icces.2011.019.115
Abstract No limitation exists virtually in target size for the classical simulation of atoms with the O(N) algorithms on parallel machines. On the other hand, the time step cannot be changed and hence the total simulation time still remains short. It is meaningful to increase the time step by the coarse-graining the atomic system. The coarse-grained particle (CGP) method has been proposed for such purposes, but it is applicable only to crystalline solids at zero-temperature limit [1,2]. The total energy of the CGP system is defined as the statistical ensemble average of the atomistic Hamiltonian under some certain constraint. For analytic… More >

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1139

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839

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Zhi Sun, Yuxiong Yan
The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 117-118, 2011, DOI:10.3970/icces.2011.019.117
Abstract Tower crane is the most generally used construction equipment for civil engineering structures. This paper proposes a method on dynamic modeling and vibration response analysis for high-rise tower cranes in operation. Concerning that tower crane structure is a beam-like lattice structure; a continuum modeling technique is firstly proposed to model the tower crane segment as a box girder element. The modeling based on this element will greatly reduce the number of degrees of freedom for tower crane dynamic analysis and thus improve analyzing efficiency. Based on the equivalent beam model, dynamic response of the tower crane induced by lifting, rotation… More >

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1145

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873

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Guojian Li, Qiang Wang, Yongze Cao, Jiaojiao Du, Jicheng He
The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 119-120, 2011, DOI:10.3970/icces.2011.019.119
Abstract This paper studies the size-dependent freezing of Co, Co-Ni, and Co-Cu clusters by using molecular dynamics with a general embedded atom method. There is size effect occurs in these three types of clusters. The clusters with large sizes always freeze to form their bulk-like structures. However, the frozen structures for small sizes are generally related to their compositions. The icosahedral clusters are formed for Co clusters (for 3.2 nm diameter) and also for Co-Ni clusters but at a larger size range (for 4.08 nm). Upon Co-Cu clusters, decohedral structure is obtained for small size (for 2.47 nm). The released energy… More >

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1146

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813

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C. J. ZHENG, H. B. CHEN, T. MATSUMOTO, T. TAKAHASHI
The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 121-122, 2011, DOI:10.3970/icces.2011.019.121
Abstract A fast multipole boundary element method is presented for three dimensional acoustic shape sensitivity analysis in this study. The Burton-Miller formula which is a linear combination of the conventional boundary integral equation and the normal derivative boundary integral equation is adopted to conquer the fictitious eigenfrequency problem associated with the conventional boundary integral equation method in solving exterior acoustic problems. The continuous adjoint variable method is implemented in the sensitivity analysis and the concept of material derivative is used in the derivation. Constant elements are employed to discretize the boundary so that the hypersingular boundary integrals contained in the formulae… More >

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1183

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904

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Yufeng Nie, Yu Zhang, Yiqiang Li, Gu YT
The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 123-124, 2011, DOI:10.3970/icces.2011.019.123
Abstract When the set of nodes distributed randomly is applied to approximate function, the size of the domain support of point has a great influence on the validity and accuracy of approximation. In order to study the radius of the support domain, this paper gives a new concept of the node density firstly, which not only can characterize the density level of distribution of the node and its calculation algorithm is simple, but also is easy to determine the radius of the support domain; Secondly, based on the concept of the node density, an algorithm which is used to search nodes… More >

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947

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Hyung-Jo Jung, Jong-Jae Lee, Jeong-Su Park
The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 125-126, 2011, DOI:10.3970/icces.2011.019.125
Abstract A vision-based displacement measurement method for structural health monitoring of large-scale infrastructures such as high-rise buildings and long-span bridges is presented. The method uses digital image processing techniques including a target recognition algorithm, projection of the captured image, and calculation of the actual displacement using target geometry and the number of pixels moved. To measure the displacement of a flexible structure from a distant location which can be regarded as a fixed reference point, a novel image processing method has been devised by means of successive estimation of relative displacement and rotational angle using a synchronized vision-based system. By measuring… More >

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1208

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912

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Elena Jakubikova, David N. Bowman
The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 127-128, 2011, DOI:10.3970/icces.2011.019.127
Abstract The Sun is an abundant source of energy capable of meeting all our energy needs if properly harvested. Some of the ways to utilize solar energy is conversion of sunlight to electricity via photovoltaic solar cells or to chemical fuels via photocatalytic synthetic cells. Many of such systems are designed around a photoactive molecule (a chromophore) anchored to a semiconductor. The conversion of sunlight to electricity occurs via absorption of light by the chromophore, followed by the interfacial electron transfer between the chromophore and semiconductor. We investigate the use of Fe(II)-polypyridine compounds as chromophores in the molecular assemblies for solar… More >

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1347

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956

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Neha Satak, John E Hurtado
The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 129-130, 2011, DOI:10.3970/icces.2011.019.129
Abstract Rigid Body Reorientation with Two Impulses: Two-axis and Single-axis Thrust Cases More >

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1173

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935

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ABSTRACT

Hua Qiao, Wei-Qiu Chen
The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 131-132, 2011, DOI:10.3970/icces.2011.019.131
Abstract The Arlequin method was first proposed by Ben Dhia aiming to provide an efficient analysis of engineering structures with some local-global property. Using reliable energy partition function and coupling operators, the Arlequin method can be used to couple two different mechanical states to conduct multi-scale or multi-model simulations.
This study explores the various applications of the Arlequin method to multi-scale or multi-model simulation of structures. The Arlequin method has been implemented into the large commercial finite element software ABAQUS by using the user defined elements (UELs). The 1D, 2D and 3D UELs have been systematically developed within the Lagrange-multipler… More >

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1140

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911

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ABSTRACT

Lin LU, Bin TENG, Bing CHEN
The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 133-134, 2011, DOI:10.3970/icces.2011.019.133
Abstract This work describes the numerical implements of a two-dimensional viscous numerical wave flume, which is based on the Finite Element Method (FEM), Computational lagrangian-Eulerian Advection Remap Volume of Fluid Method (CLEAR-VOF), internal wave generation and artificial wave damping technique. Owning to the inherent consistence of CLEAR-VOF with FEM, the present numerical model allows the simulations of wave propagation and interaction with structures to be simulated with irregular mesh partition. The present numerical wave flume is validated by several applications in comparisons with available experimental data and numerical results, including the problems of standing wave trains in front of vertical wall,… More >

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935