Andang Sunarto^1,*, Praveen Agarwal^2,3,4, Jumat Sulaiman⁵, Jackel Vui Lung Chew⁶

Intelligent Automation & Soft Computing, Vol.31, No.2, pp. 1173-1184, 2022, DOI:10.32604/iasc.2022.020542

Abstract Solving time-fractional diffusion equation using a numerical method has become a research trend nowadays since analytical approaches are quite limited. There is increasing usage of the finite difference method, but the efficiency of the scheme still needs to be explored. A half-sweep finite difference scheme is well-known as a computational complexity reduction approach. Therefore, the present paper applied an unconditionally stable half-sweep finite difference scheme to solve the time-fractional diffusion equation in a one-dimensional model. Throughout this paper, a Caputo fractional operator is used to substitute the time-fractional derivative term approximately. Then, the stability of the difference scheme combining the… More >

Haishan Lu, Shuguang Gong^*, Jianping Zhang, Guilan Xie, Shuohui Yin

CMES-Computer Modeling in Engineering & Sciences, Vol.128, No.3, pp. 1151-1178, 2021, DOI:10.32604/cmes.2021.016165

Abstract We proposed an improved graphics processing unit (GPU) acceleration approach for three-dimensional structural topology optimization using the element-free Galerkin (EFG) method. This method can effectively eliminate the race condition under parallelization. We established a structural topology optimization model by combining the EFG method and the solid isotropic microstructures with penalization model. We explored the GPU parallel algorithm of assembling stiffness matrix, solving discrete equation, analyzing sensitivity, and updating design variables in detail. We also proposed a node pair-wise method for assembling the stiffness matrix and a node-wise method for sensitivity analysis to eliminate race conditions during the parallelization. Furthermore, we… More >

Park Chan-Yeob, Hyun-Ro Jae, Jun-Yong Jang, Song Hyoung-Kyu^*

CMC-Computers, Materials & Continua, Vol.68, No.1, pp. 137-148, 2021, DOI:10.32604/cmc.2021.016108

Abstract Linear precoding methods such as zero-forcing (ZF) are near optimal for downlink massive multi-user multiple input multiple output (MIMO) systems due to their asymptotic channel property. However, as the number of users increases, the computational complexity of obtaining the inverse matrix of the gram matrix increases. For solving the computational complexity problem, this paper proposes an improved Jacobi (JC)-based precoder to improve error performance of the conventional JC in the downlink massive MIMO systems. The conventional JC was studied for solving the high computational complexity of the ZF algorithm and was able to achieve parallel implementation. However, the conventional JC… More >

Zhongxu Yin^{1, *}, Yiran Song², Huiqin Chen³, Yan Cao⁴

CMC-Computers, Materials & Continua, Vol.63, No.2, pp. 1013-1029, 2020, DOI:10.32604/cmc.2020.09345

Abstract Security-sensitive functions are the basis for building a taint-style vulnerability model. Current approaches for extracting security-sensitive functions either don’t analyze data flow accurately, or not conducting pattern analyzing of conditions, resulting in higher false positive rate or false negative rate, which increased manual confirmation workload. In this paper, we propose a security sensitive function mining approach based on preconditon pattern analyzing. Firstly, we propose an enhanced system dependency graph analysis algorithm for precisely extracting the conditional statements which check the function parameters and conducting statistical analysis of the conditional statements for selecting candidate security sensitive functions of the target program.… More >

De la Rosa M¹, L Arce¹, JA Villarreal¹, L Ibarra², J Lozano³

Phyton-International Journal of Experimental Botany, Vol.81, pp. 165-168, 2012, DOI:10.32604/phyton.2012.81.165

Abstract Simojovel pepper seeds were first treated with 0.5 M NaCl, and then put to germinate in solutions of gibberellic acid at different concentrations. Initially, seeds were either preconditioned or not with NaCl combined with 0, 100, 200, 300 or 400 mg/L gibberellic acid. In a second phase of the study, seeds preconditioned with NaCl were exposed to 0, 350, 400, 450 or 500 mg/L gibberellic acid. Experiments were arranged in a completely randomized design with a factorial arrangement of 2 x 5 with four replications. The greatest (p≤0.01) germination percentage (91.75%) was obtained on seeds previously exposed to NaCl and… More >

M. Rodríguez, B. Buchholz, V. D’Annuzio, M. Donato, G.E. González, M. A. Goyeneche, T. Mazo, V. Pérez, L. Wilensky, R.J. Gelpi^*

BIOCELL, Vol.40, No.1, pp. 43-46, 2016, DOI:10.32604/biocell.2016.40.043

Abstract Dystrophin is a membrane-associated protein responsible for structural stability of the sarcolemma in cardiac myocytes and is very sensitive to ischemic damage. The goal of our study was to determine if ischemic preconditioning could prevent dystrophin breakdown through inhibition of matrix metalloproteinase-2 (MMP-2) activity. Isolated rabbit hearts were subjected to global ischemia with or without reperfusion in order to evaluate if dystrophin is preserved by ischemic preconditioning through MMP-2 inhibition. Ischemic preconditioning significantly reduced the infarct size induced by 30 min of ischemia and 180 min of reperfusion. Importantly, it also diminished dystrophin proteolysis and attenuated MMP-2 activity after 30… More >

S.H. Ju¹

CMES-Computer Modeling in Engineering & Sciences, Vol.64, No.1, pp. 91-109, 2010, DOI:10.3970/cmes.2010.064.091

Abstract This study develops an OpenMP scheme to parallel the preconditioned conjugate gradient methods (PCG) in shared memory computers. The proposed method is simple and systematic, so a minor change in traditional PCG methods may produce effective parallelism. At first, the global stiffness matrix is re-numbered in order to produce a parallel three-line form matrix, and a subroutine only needs to be called once in the finite element analysis. Several basic OpenMP commands are then added into the traditional incomplete Cholesky factorization (ILU) and symmetric successive over-relaxation (SSOR) codes to make the procedures of matrix multiplication, decomposition, forward substitution, and backward… More >

S.N. Lee¹, S.W. Baek¹, K.M. Kim², M.J. Yu³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.15, No.1, pp. 1-8, 2010, DOI:10.3970/icces.2010.015.001

Abstract A finite volume method with nongray gases is applied to examine the radiative base heating due to plume which is changed by mechanical deflection. Numerical approaches are made to predict the effect of TVC. The radiative properties within plume flow are modeled with the weighted sum of 4 gray gases. The exhaust plume is considered as an absorbing and emitting medium with no scattering. Flow field is molded with using Preconditioned Navier-Stokes(N-S) algorithms with multi-block. The Geometric Conservation Law(GCL) is considered to compute the nozzle moving mechanism. The radiative base heating is changed by the nozzle deflection angle. More >

N. Mai-Duy¹, T. Tran-Cong¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.14, No.2, pp. 51-56, 2010, DOI:10.3970/icces.2010.014.051

Abstract This paper presents a preconditioning scheme to improve the condition number of integrated radial-basis-function (RBF) matrices in solving large-scale 2D elliptic problems. The problem domain is discretised using a Cartesian grid, over which integrated RBF networks are employed to represent the field variable. The present preconditioner is constructed from 1D integrated RBF networks along grid lines. Test problems defined on rectangular and non-rectangular domains are employed to study the performance of the scheme. More >

Suely Oliveira², Fang Yang²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.3, No.2, pp. 113-120, 2007, DOI:10.3970/icces.2007.003.113

Abstract In this paper we describe and compare preconditioners for saddle-point systems obtained from meshfree discretizations, using the concepts of hierarchical (or H-)matrices. Previous work by the authors using this approach did not use H-matrix techniques throughout, as is done here. Comparison shows the method described here to be better than the author's previous method, an AMG method adapted to saddle point systems, and conventional iterative methods such as JOR. More >