T. Aizawa¹, H. Akebono², H.Suzuki¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.5, No.4, pp. 193-198, 2008, DOI:10.3970/icces.2008.005.193

Abstract In order to achieve power transmission parts like a compact gearwheel which indicates high performance properties, hybrid surface modification was performed by combining Super Rapid Induction Heating & Quenching(SRIQ) which creates high fatigue strength and Diamond Like Carbon (DLC) coating which are well known for their high hardness, low friction and excellent wear resistance. And, in order to prevent the base material from decreasing its fatigue strength, DLC was coated by using Unbalanced Magnetron Sputtering (UBMS) method which can coat at low temperature. Rotational bending fatigue tests and friction-wear tests were carried out. It was More >

G.M. Kulikov¹, E. Carrera², S.V. Plotnikova¹, S. Brischetto²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.5, No.3, pp. 187-192, 2008, DOI:10.3970/icces.2008.005.187

Abstract This paper presents the geometrically exact assumed stress-strain four-node element with nine displacement degrees of freedom per node. The finite element formulation developed is based on the 9-parameter shell model by employing a new concept of interpolation surfaces (I-surfaces) inside the shell body. We introduce three I-surfaces and choose nine displacements of these surfaces as fundamental shell unknowns. Such choice allows us to represent the higher-order shell formulation in a very compact form and to derive in curvilinear reference surface coordinates the strain-displacement relationships, which are objective, i.e. invariant under all rigid-body motions. More >

L.C.G. DeSouza¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.5, No.3, pp. 163-172, 2008, DOI:10.3970/icces.2008.005.163

Abstract Satellite Attitude Control System usually does not have all the states available for feedback; therefore, full state estimation by any sort of filtering methodology becomes essential. A good estimation algorithm must filter out the undesirable noise from the measurement signal. Kalman Filter (KF) technique is a traditional procedure to estimate the states of a linear system that are not always measured directly by the sensors, minimizing the variance of the estimated error. However, the KF is not fully robustness proven in face of unpredictable noise sources and it is not always able to minimize the… More >

FU Zhiliang¹, GUO Hua², GAO Yanfa³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.5, No.3, pp. 145-156, 2008, DOI:10.3970/icces.2008.005.145

Abstract This paper is focused on the micro-damage evolution properties of gray green mudstone under impacting disturbance load conditions for the first time by using the real time CT testing technique. CT images and CT values for rock cross-sections under different impacting disturbance loading levels were obtained. The paper is also to describe process of rock creep damage under disturbance loads and to explore the mechanism of micro-damage. The results have shown that rock failure is easy to happen suddenly rock is in or close to limit strength neighborhood during the process of disturbance. This will More >

K. Y. Liu^1,2, S. Y. Long^1,2,3, G. Y. Li¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.5, No.2, pp. 99-120, 2008, DOI:10.3970/icces.2008.005.099

Abstract A meshless local Petrov-Galerkin method (MLPG)^[1] for the analysis of cracks in isotropic functionally graded materials is presented. The meshless method uses the moving least squares (MLS) to approximate the field unknowns. The shape function has not the Kronecker Delta properties for the trial-function-interpolation, and a direct interpolation method is adopted to impose essential boundary conditions. The MLPG method does not involve any domain and singular integrals to generate the global effective stiffness matrix if body force is ignored; it only involves a regular boundary integral. The material properties are smooth functions of spatial coordinates and More >

S. Itoh¹, K. Taguchi¹, Y. Umemoto¹, H. Serizawa¹, H. Murakawa¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.5, No.2, pp. 47-54, 2008, DOI:10.3970/icces.2008.005.047

Abstract The authors have proposed Fractal and Hierarchical Multi-Grid Methods for solving ultra large FE problems [1, 2]. In these methods, the domain to be analyzed is subdivided into multi-grid which has fractal or hierarchical structure and the solution is obtained by solving equations for small cells or nodes at each hierarchy successively. In this research, potential capability of a Hierarchical Multi-Grid method is examined through simple example problems. More >

Chen X.Y.^∗,†, Liu Y.^2,‡, Fu B.M.^§, Fan J.T.^¶, Yang J.M.¹

Molecular & Cellular Biomechanics, Vol.5, No.4, pp. 275-284, 2008, DOI:10.3970/mcb.2008.005.275

Abstract Surface glycocalyx, as a barrier to material exchange between circulating blood and body tissues, can be treated as a periodic square array of cylindrical fibers. Previous study treated the glycocalyx as porous media and simulated by continuum theory. However, it has recently been found that a relatively hexagonal fibre-matrix structure may be responsible for the ultrafiltration properties of microvascular walls. The fibre-matrix is an underlaying three-dimensional meshwork with a fibre diameter of 10$\sim$12 nm and characteristic spacing of about 20 nm. The porous medium model does not consider the particle size, when the particle size… More >

Chun Yang^∗,†, Dalin Tang^∗,‡, Shunichi Kobayashi^§, Jie Zheng^¶, Pamela K. Woodard^§, Zhongzhao Teng^*, Richard Bach^||, David N. Ku^∗∗

Molecular & Cellular Biomechanics, Vol.5, No.4, pp. 259-274, 2008, DOI:10.3970/mcb.2008.005.259

Abstract Many acute cardiovascular syndromes such as heart attack and stroke are caused by atherosclerotic plaque ruptures which often happen without warning. MRI-based models with fluid-structure interactions (FSI) have been introduced to perform flow and stress/strain analysis for atherosclerotic plaques and identify possible mechanical and morphological indices for accurate plaque vulnerability assessment. In this paper, cyclic bending was added to 3D FSI coronary plaque models for more accurate mechanical predictions. Curvature variation was prescribed using the data of a human left anterior descending (LAD) coronary artery. Five computational models were constructed based on ex vivo MRI… More >

Colin K. Choi^*, Brian P. Helmke^∗,†

Molecular & Cellular Biomechanics, Vol.5, No.4, pp. 247-258, 2008, DOI:10.3970/mcb.2008.005.247

Abstract Hemodynamic shear stress guides a variety of endothelial phenotype characteristics, including cell morphology, cytoskeletal structure, and gene expression profile. The sensing and processing of extracellular fluid forces may be mediated by mechanotransmission through the actin cytoskeleton network to intracellular locations of signal initiation. In this study, we identify rapid actin-mediated morphological changes in living subconfluent and confluent bovine aortic endothelial cells (ECs) in response to onset of unidirectional steady fluid shear stress (15 dyn/cm²). After flow onset, subconfluent cells exhibited dynamic edge activity in lamellipodia and small ruffles in the downstream and side directions for the… More >

Abhijit Sinha Roy^*, Lloyd H. Back^†, Rupak K. Banerjee^‡

Molecular & Cellular Biomechanics, Vol.5, No.4, pp. 229-246, 2008, DOI:10.3970/mcb.2008.005.229

Abstract The in vivo and ex vivo compliance of arteries are expected to be closely related and estimated. Fluid-structure interaction analysis can assess the agreement between the two compliances. To evaluate this hypothesis, a pulsatile fluid-structure interaction analysis of blood flow in femoral artery of a dog was conducted using: (1) measured in vivo mean pressure (72.5 mmHg), mean pressure drop (0.59 mmHg), mean velocity (15.1 cm/sec); and (2) ex vivo measurements of non -- linear elastic properties of femoral artery. Additional analyses were conducted for physiological pressures (104.1 and 140.7 mmHg) and blood flow using a characteristic linear pressure More >