Chein-Shan Liu¹, Satya N. Atluri²

CMES-Computer Modeling in Engineering & Sciences, Vol.43, No.3, pp. 253-276, 2009, DOI:10.3970/cmes.2009.043.253

Abstract Since the works of Newton and Lagrange, interpolation had been a mature technique in the numerical mathematics. Among the many interpolation methods, global or piecewise, the polynomial interpolation p(x) = a₀ + a₁x + ... + a_nxⁿ expanded by the monomials is the simplest one, which is easy to handle mathematically. For higher accuracy, one always attempts to use a higher-order polynomial as an interpolant. But, Runge gave a counterexample, demonstrating that the polynomial interpolation problem may be ill-posed. Very high-order polynomial interpolation is very hard to realize by numerical computations. In this paper we propose a… More >

Yongjie Zhang¹, Wenyan Wang¹, Xinghua Liang¹, Yuri Bazilevs², Ming-Chen Hsu², Trond Kvamsdal³, Reidar Brekken⁴, Jørgen Isaksen⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.42, No.2, pp. 131-150, 2009, DOI:10.3970/cmes.2009.042.131

Abstract This paper describes a comprehensive and high-fidelity finite element meshing approach for patient-specific arterial geometries from medical imaging data, with emphasis on cerebral aneurysm configurations. The meshes contain both the blood volume and solid arterial wall, and are compatible at the fluid-solid interface. There are four main stages for this meshing method: 1) Image segmentation and geometric model construction; 2) Tetrahedral mesh generation for the fluid volume using the octree-based method; 3) Mesh quality improvement stage, in which edge-contraction, pillowing, optimization, geometric flow smoothing, and mesh cutting are applied to the fluid mesh; and 4) More >

Chein-Shan Liu¹, Satya N. Atluri²

CMES-Computer Modeling in Engineering & Sciences, Vol.41, No.3, pp. 243-262, 2009, DOI:10.3970/cmes.2009.041.243

Abstract The Fictitious Time Integration Method (FTIM) previously developed by Liu and Atluri (2008a) is employed here to solve a system of ill-posed linear algebraic equations, which may result from the discretization of a first-kind linear Fredholm integral equation. We rationalize the mathematical foundation of the FTIM by relating it to the well-known filter theory. For the linear ordinary differential equations which are obtained through the FTIM (and which are equivalently used in FTIM to solve the ill-posed linear algebraic equations), we find that the fictitous time plays the role of a regularization parameter, and its More >

S. Abdullah¹

Structural Durability & Health Monitoring, Vol.4, No.4, pp. 181-198, 2008, DOI:10.3970/sdhm.2008.004.181

Abstract This paper describes a technique to identify the important features in fatigue road spectrum loading, for which these features cause the majority of the total damage. Fatigue damaging events, called bump segments, are extracted from the spectrum loading using a wavelet-based algorithm, called Wavelet Bump Extraction (WBE). This algorithm is also used to produce a shortened mission signal that retains most of the fatigue damage whilst preserving the cycle sequences. The bump identification process has been evaluated by analysing two road spectrum loadings having a variable amplitude pattern. These data sets were obtained from the… More >

U.Suryanarayana Murty¹, V.Sreehari Rao²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.5, No.2, pp. 121-128, 2008, DOI:10.3970/icces.2008.005.121

Abstract Artificial intelligence has opened a new window of opportunity and has definitely a long way to look ahead in\nobreakspace {}area of data analysis. The enormity of magnitude of data and its complex nature often perplex the epidemiologists. This is especially true in case of vector borne diseases where a timely and precise understanding of disease during decision making process comes handy for curbing the diseases in event of an outbreak or epidemic. Often the public health officials feel the need of correct identification of true positive cases. A tool that classify disease according to presence More >

LiviuMarin ¹

CMES-Computer Modeling in Engineering & Sciences, Vol.37, No.3, pp. 203-242, 2008, DOI:10.3970/cmes.2008.037.203

Abstract In this paper, a meshless method for the stable solution of direct and inverse problems associated with the two-dimensional Laplace equation in the presence of boundary singularities and noisy boundary data is proposed. The governing equation and boundary conditions are discretized by the method of fundamental solutions (MFS), whilst the existence of the boundary singularity is taken into account by subtracting from the original MFS solution the corresponding singular solutions, as given by the asymptotic expansion of the solution near the singular point. However, even in the case when the boundary singularity is accounted for, More >

Chun Yang¹, Dalin Tang², Chun Yuan³, William Kerwin², Fei Liu³, Gador Canton³, Thomas S. Hatsukami^3,4, Satya Atluri⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.28, No.2, pp. 95-108, 2008, DOI:10.3970/cmes.2008.028.095

Abstract Atherosclerotic plaque rupture and progression have been the focus of intensive investigations in recent years. Plaque rupture is closely related to most severe cardiovascular syndromes such as heart attack and stroke. A computational procedure based on meshless generalized finite difference (MGFD) method and serial magnetic resonance imaging (MRI) data was introduced to quantify patient-specific carotid atherosclerotic plaque growth functions and simulate plaque progression. Participating patients were scanned three times (T₁,T₂, and T₃, at intervals of about 18 months) to obtain plaque progression data. Vessel wall thickness (WT) changes were used as the measure for plaque progression.… More >

Chein-Shan Liu¹, Jiang-Ren Chang², Kai-Huey Chang², Yung-Wei Chen²

CMC-Computers, Materials & Continua, Vol.7, No.2, pp. 97-108, 2008, DOI:10.3970/cmc.2008.007.097

Abstract For the inverse vibration problem a mathematical method is required to determine unknown parameters from the measurement of vibration data. When both damping and stiffness functions are identified, it is a rather difficult problem. In this paper we will propose a feasible method to simultaneously estimate both the time-dependent damping and stiffness coefficients through three mathematical transformations. First, the second-order equation of motion is transformed into a self-adjoint first-order system by using the concept of integrating factor. Then, we transform these two ODEs into two hyperbolic type PDEs. Finally, we apply a one-step group preserving More >

Jin Yeon Cho¹, Yun Hyuk Choi², You Me Song³, Chang Sik Kim⁴

The International Conference on Computational & Experimental Engineering and Sciences, Vol.4, No.3, pp. 151-158, 2007, DOI:10.3970/icces.2007.004.151

Abstract In this work, PDSL(pre-detection sort last) and SDSL(strip-wise decomposition sort last) parallel visualization algorithms are proposed for efficient visualization of massive data generated from large-scale parallel finite element analysis through investigating the characteristics of distributed parallel finite element analysis procedure. The proposed parallel visualization algorithms are based on the sort last approach, and designed to be highly compatible with the characteristics of domain-wise computation in parallel finite element analysis. To investigate the performances of proposed algorithms, in-house software is developed by applying the binary tree network communication pattern along with the proposed sorting algorithms, and More >

KARINA SAYURI UTSUNOMIYA*, MARIA SUELY PAGLIARINI*, CACILDA BORGES DO VALLE**

BIOCELL, Vol.29, No.3, pp. 295-301, 2005, DOI:10.32604/biocell.2005.29.295

Abstract The genus Brachiaria (Trin.) Griseb. has achieved considerable importance to cattle production systems, as a result of the good production and adaptation of a few cultivars to poor and acid soils of the Brazilian savannas. Many of its species and accessions are polyploid and apomictic, which limits direct hybridization. To assist the breeding program, cytogenetic characterization has been undertaken on the accessions of Brachiaria collection at the Embrapa Beef Cattle Research Center. In this study, chromosome number and meiotic behavior are reported for the Brachiaria nigropedata (Ficalho & Hiern) Stapf collection. The 20 available accessions are tetraploid… More >