Che-Wun Hong^1,2, Chia-Yun Tsai¹

CMES-Computer Modeling in Engineering & Sciences, Vol.67, No.2, pp. 79-94, 2010, DOI:10.3970/cmes.2010.067.079

Abstract This paper describes the quantum mechanical simulation on the photonic properties of group-III nitride clusters, whose bulk types are common materials for light emitting diodes (LEDs). In order to emit different colors of light using the same semiconductor materials, it is possible to vary the band gap by controlling the quantum dot sizes or doping a third atom theoretically. Density functional theory (DFT) calculations are performed to analyze a set of binary (GaN)_n (3≤n≤32) and ternary In_xGa_1-xN (0≤x≤0.375) clusters to study their photonic characteristics. The ground state structures are optimized to calculate the binding energies using More >

Mahdi Izadi¹, Mohd Zainal Abidin Ab. Kadir¹

CMES-Computer Modeling in Engineering & Sciences, Vol.67, No.1, pp. 1-12, 2010, DOI:10.3970/cmes.2010.067.001

Abstract Evaluation of electric field due to indirect lightning strike is an interesting subject. Calculation of electric and magnetic fields in time domain with the consideration of ground conductivity effect in the shortest possible time is an important objective. In this paper, using dipole method, Maxwell's equation and Cooray-Rubinstein formula, a new method for calculation of electric field in time domain is proposed. In addition, this proposed algorithm can also be used to evaluate the effect at the far distance cases of observation point from lightning channel. More >

Chein-Shan Liu¹, Hong-Ki Hong¹, Satya N. Atluri²

CMES-Computer Modeling in Engineering & Sciences, Vol.60, No.3, pp. 279-308, 2010, DOI:10.3970/cmes.2010.060.279

Abstract We propose novel algorithms to calculate the inverses of ill-conditioned matrices, which have broad engineering applications. The vector-form of the conjugate gradient method (CGM) is recast into a matrix-form, which is named as the matrix conjugate gradient method (MCGM). The MCGM is better than the CGM for finding the inverses of matrices. To treat the problems of inverting ill-conditioned matrices, we add a vector equation into the given matrix equation for obtaining the left-inversion of matrix (and a similar vector equation for the right-inversion) and thus we obtain an over-determined system. The resulting two modifications… More >

J.A.Ferreira^2,3, P. Oliveira¹, P.M. Silva⁴, A. Carreira^5,3, J.N. Murta⁶

CMES-Computer Modeling in Engineering & Sciences, Vol.60, No.2, pp. 151-180, 2010, DOI:10.3970/cmes.2010.060.151

Abstract This paper focuses on the release of an ophthalmic drug (flurbiprofen) from a loaded copolymer where the drug is simultaneously dispersed in the polymeric matrix and entrapped in particles. The copolymer is based in 2-hydroxyethyl methacrylate co-methacrylic acid and silicone is used to prepare the loaded particles. A mathematical model to simulate the drug release is proposed and a qualitative analysis is performed. In vitro experimental results are compared with simulation results. Contact lens made from the presented copolymer are expected to deliver drug at therapeutical levels for a few days. More >

Dalin Tang¹, Chun Yang^1,2, Tal Geva^3,4, Glenn Gaudette⁴, and Pedro J. del Nido⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.56, No.2, pp. 113-130, 2010, DOI:10.3970/cmes.2010.056.113

Abstract Right and left ventricle (RV/LV) combination models with three different patch materials (Dacron scaffold, treated pericardium, and contracting myocardium), two-layer construction, fiber orientation, and active anisotropic material properties were introduced to evaluate the effects of patch materials on RV function. A material-stiffening approach was used to model active heart contraction. Cardiac magnetic resonance (CMR) imaging was performed to acquire patient-specific ventricular geometries and cardiac motion from a patient with severe RV dilatation due to pulmonary regurgitation needing RV remodeling and pulmonary valve replacement operation. Computational models were constructed and solved to obtain RV stroke volume,… More >

X.P. Shen, A. Diaz¹, T. Sheehy²

CMC-Computers, Materials & Continua, Vol.20, No.3, pp. 205-224, 2010, DOI:10.3970/cmc.2010.020.205

Abstract This paper presents a case study for the design of a mud-weight window (MWW) with three-dimensional (3-D), finite-element (FE) tools for subsalt wells. The trajectory of the target well penetrates a 7 km thick salt body. A numerical scheme has been proposed for calculating the shear failure gradient (SFG) and fracture gradient (FG) with 3-D FE software. User subroutines have been developed to address non-uniform pore-pressure distribution. A series of FE calculations were performed to obtain the MWW of the target wellbore, which consists of the SFG and FG for the subsalt sections. Although no… More >

X.P. Shen¹, J.L. Feng²

CMC-Computers, Materials & Continua, Vol.20, No.2, pp. 185-204, 2010, DOI:10.3970/cmc.2010.020.185

Abstract The characteristic length of a gradient-dependent damage model is a key parameter, which is usually regarded as the length of damage process zone (DPZ). Value and evolution of the size of DPZ were investigated by both a numerical method and an experimental manner. In the numerical study, the geometrical model adopted was a set of four-point shearing beams; the numerical tool used was the Abaqus/Explicit software. The distance between the front and end of a complete DPZ was obtained. Values of strain components at these points were given out at given time points. The experimental… More >

Zoran Ivanovic

European Cytokine Network, Vol.20, No.1, pp. 7-9, 2009, DOI:10.1684/ecn.2009.0144

Abstract This article has no abstract. More >

Marco Presta¹, Domenico Ribatti²

European Cytokine Network, Vol.20, No.4, pp. 157-157, 2009, DOI:10.1684/ecn.2009.0171

Abstract This article has no abstract. More >

Ochoa-Fuentes YM¹, E Cerna², J Landeros², O Vazquez¹, V Olalde³, A Flores²

Phyton-International Journal of Experimental Botany, Vol.78, pp. 25-30, 2009, DOI:10.32604/phyton.2009.78.025

Abstract Forty two Mexican isolates of Phytophthora cinnamomi Rands were examined for genetic diversity by the random amplified polymorphic DNA assay. The amount of genetic variation was evaluated by polymerase chain reaction amplification with a set of twenty one random 10-mer primers. All amplifications revealed scorable polymorphisms among the isolates, and a total of 23 band positions were scored for the 21 primers tested. Genetic distances among the isolates were calculated, and cluster analysis was used to generate a dendogram which showed relationships between them. These results suggest that the geographic groups were strong. More >