K. Han ¹, Y. T. Feng ¹, D. R. J. Owen¹

CMES-Computer Modeling in Engineering & Sciences, Vol.18, No.2, pp. 87-100, 2007, DOI:10.3970/cmes.2007.018.087

Abstract Numerical procedures are introduced for simulations of irregular particle transport in turbulent flows using the coupled lattice Boltzmann method (LBM) and the discrete element method (DEM). The fluid field is solved by the extended LBM with the incorporation of the Smagorinsky turbulence approach, while particle interaction is modeled by the DEM. The hydrodynamic interactions between fluid and particles are realised through an immersed boundary condition, which gives rise to a coupled solution strategy to model the fluid-particle system under consideration. Main computational aspects comprise the lattice Boltzmann formulation for the solution of fluid flows; the More >

G. Dziatkiewicz¹ and P. Fedelinski¹

CMES-Computer Modeling in Engineering & Sciences, Vol.17, No.1, pp. 35-46, 2007, DOI:10.3970/cmes.2007.017.035

Abstract The aim of the present work is to show the formulation and application of the dual reciprocity boundary element method (BEM) to free vibrations of two-dimensional piezoelectric structures. The piezoelectric materials are modelled as homogenous, linear -- elastic, transversal isotropic and dielectric. Displacements and electric potentials are treated as generalized displacements and tractions and electric charge flux densities are treated as generalized tractions. The static fundamental solutions, which are required in the proposed approach, are derived using the Stroh formalism. The domain inertial integral is transformed to the equivalent boundary integral using the dual reciprocity More >

D. Soares Jr.^1,2, W.J. Mansur¹, D.L. Lima³

CMES-Computer Modeling in Engineering & Sciences, Vol.17, No.1, pp. 19-34, 2007, DOI:10.3970/cmes.2007.017.019

Abstract The present paper discussion is concerned with the development of robust and efficient algorithms to model propagation of interacting acoustic and elastic waves. The paper considers acoustic-elastic, acoustic-acoustic and elastic-elastic partitioned analyses of coupled systems; however, the focus here is the acoustic-elastic coupling considering finite elements and the acoustic-acoustic coupling considering finite elements and finite differences (other coupling procedures can be implemented analogously). One important feature of the algorithms presented is that they allow considering different time-steps for different sub-domains; so it is possible to substantially improve efficiency, accuracy and stability of the central difference More >

Joseph G. Lawrence, John P. Dismukes, Arunan Nadarajah¹

FDMP-Fluid Dynamics & Materials Processing, Vol.3, No.3, pp. 255-264, 2007, DOI:10.3970/fdmp.2007.003.255

Abstract The atmospheric chemical vapor deposition process on continuous glass sheets is a well developed one and the parameters that affect it are relatively well understood. When this process is converted to coat discrete glass plates it introduces a new variable, the gap between the glass plates, which can significantly impact the quality of the coatings. In this study a 2D pseudo steady state model of the process was developed to study the effect of the gap, and the ratio of outlet to inlet gas flow rates (called the bias), on the coating quality. The model… More >

G. Q. Xie^1,2,3, X. Han², S. Y. Long³

CMC-Computers, Materials & Continua, Vol.6, No.1, pp. 1-12, 2007, DOI:10.3970/cmc.2007.006.001

Abstract A multi-walled carbon nanotube is modeled as a multiple-elastic cylindrical structure. The numerical-analytical method is adopted to analyze the characteristics of harmonic waves propagating along an anisotropic carbon nanotube. Each wall of the carbon nanotube is divided into three-nodal-line layer elements. The deflections of two adjacent tubes are coupled through the van der Waals. The governing equation of element is obtained from Hamilton's principle. A set of system equation of dynamics equilibrium for the entire structure is obtained by the assembling of all the elements. From solution of the eigenvalue equations, the dispersive characteristics, group More >

Le-Chung Shiau¹, Shih-Yao Kuo²

CMC-Computers, Materials & Continua, Vol.5, No.3, pp. 213-222, 2007, DOI:10.3970/cmc.2007.005.213

Abstract A high precision high order triangular plate element is developed for the linear flutter analysis of thermally buckled composite sandwich plates. Due to uneven thermal expansion in the two local material directions, the buckling mode of the plate may be shifted from one pattern to another for certain fiber orientation or plate aspect ratio as the aerodynamic pressure is present. This buckle pattern change alters the frequencies and modes of the plate and that in turn changes the flutter coalescent modes. Numerical results show that temperature has a destabilizing effect on the flutter boundary but More >

Deb Feldman-Stewart^1,2, Michael D. Brundage^1,2,3, Rob Siemens⁴, David Skarsgard⁵

Canadian Journal of Urology, Vol.13, No.6, pp. 3321-3326, 2006

Abstract Purpose: To compare the helpfulness of two educational aids or booklets on early-stage prostate cancer.
Method: Participating consecutive patients and a family member, in three centres, received one of two booklets, one produced by AstraZeneca (AZ), the other produced by us (CCE); the patient and family shared a booklet but were separate study participants. The primary outcome was the Purpose-based Information Assessment completed after participants read their booklet; they rated the importance (4-point Likert scale) of six potential purposes for the information: to help organize their thoughts, understand their situations, decide on treatment, plan, provide emotional support… More >

P.D. Shah¹, Ch. Song², C.L. Tan¹, X. Wang¹

Structural Durability & Health Monitoring, Vol.2, No.4, pp. 225-238, 2006, DOI:10.3970/sdhm.2006.002.225

Abstract Numerical T-stress solutions in two dimensional anisotropic cracked bodies are very scarce in the literature. Schemes to evaluate this fracture parameter in anisotropy have been reported only fairly recently. Among them are those developed in conjunction with two different computational techniques, namely, the Boundary Element Method (BEM) and the Scaled Boundary Finite-Element Method (SBFEM). This paper provides a review of the respective schemes using these techniques and demonstrates their efficacy with three examples. These examples, which are of engineering importance, involve cracks lying in a homogeneous medium as well as at the interface between dissimilar media. More >

P. Fedelinski¹, R. Gorski¹

CMES-Computer Modeling in Engineering & Sciences, Vol.15, No.1, pp. 31-40, 2006, DOI:10.3970/cmes.2006.015.031

Abstract The aim of the present work is to analyze and optimize plates in plane strain or stress with stiffeners subjected to dynamic loads. The reinforced structures are analyzed using the coupled boundary and finite element method. The plates are modeled using the dual reciprocity boundary element method (DR-BEM) and the stiffeners using the finite element method (FEM). The matrix equations of motion are formulated for the plate and stiffeners. The equations are coupled using conditions of compatibility of displacements and equilibrium of tractions along the interfaces between the plate and stiffeners. The final set of… More >

Baohua Ji^*, Yonggang Huang^†

Molecular & Cellular Biomechanics, Vol.3, No.3, pp. 109-120, 2006, DOI:10.3970/mcb.2006.003.109

Abstract The mechanisms governing the self-assembled structure of biomolecules (single chain and bundle of chains) are studied with an AB copolymer model via the coarse grained molecular dynamics simulations. Non-local hydrophobic interaction is found to play a critical role in the pattern formation of the assembled structure of polymer chains. We show that the polymer structure could be controlled by adjusting the balance between local (short range) and non-local (long range) hydrophobic interaction which are influenced by various factors such as the sequences, chain length, stiffness, confinement, and the topology of polymers. In addition, the competition More >