Hongying Huang, Dehao Yu

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.2, pp. 65-66, 2011, DOI:10.3970/icces.2011.017.065

Abstract In this paper, we apply the coupling of local discontinuous Galerkin(LDG) and natural boundary element (NBE) methods to solve a class of exterior transmission problems in the plane. As a consequence, the main features of LDG and NBEM are maintained and hence the coupled approach benefits from the advantages of both methods. Referring to cite{Gatica2010}, we employ LDG subspaces whose functions are continuous on the coupling boundary. The continuity can be implemented either directly. In this way, the normal derivative becomes the only boundary unknown, and hence the total number of unknown functions is reduced by two. We prove the… More >

Zixin Zhang, Qinghua Lei, Yongchang Cai

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.2, pp. 63-64, 2011, DOI:10.3970/icces.2011.017.063

Abstract Realistic computer models of fracture-block systems have significant impacts on the performance of Block-group Model of fractured rock mass, especially for hydro-mechanical problems. In this paper, a reasonable and effective algorithm for block system construction and visualization is presented. The methodology is based on CAGD Computer Aided Geometric Design and employs object oriented programming (OOP) technique to organize project data, including input parameters, research objects, graphic information and analytical results.

The use of traditional key-block theory for the analysis of blocky rock mass structures in mining and civil engineering is well established. And such methods have been used to… More >

F. ZHANG, S. ZHANG, Y. L. XIONG, H. NAKANO, T. NISHIMURA

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.2, pp. 61-62, 2011, DOI:10.3970/icces.2011.017.061

Abstract In deep geological disposal for high-level radioactive waste (HLW), one of the most important factors is to study the thermo-hydraulic-mechanical (THM) behavior of natural barrier that consists of host rock, most made from sedimentary rock or granite. In this paper, based on a new simple thermo-elasto-viscoplastic model of soft rock proposed by Zhang & Zhang (2009), a program of finite element method (FEM) has been developed to simulate the above-mentioned THM behavior of geological disposal. 2D and 3D analyses are conducted to estimate long-term stability of the host rock. The men-made barrier, usually composed of buffer material of bentonite, metal… More >

B. Liu¹, D. Tang²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.2, pp. 55-60, 2011, DOI:10.3970/icces.2011.017.055

Abstract The effects of the non-Newtonian blood viscosity on the wall shear stress (WSS) of the blood flows in stenotic right coronary arteries have been investigated by computer simulations. The numerical calculations were performed using the Newtonian Model and the non-Newtonian models with the fluid obeying the Power Law and the Carreau models for the simulations of unsteady blood flows. The differences on the spatial and temporal WSS distribution patterns due to the different blood properties were compared. The computational results demonstrate that the blood viscosity properties do not affect the spatial WSS distribution pattern qualitatively. The region on the inner… More >

DaMing Yuan, XiaoLiang Cheng

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.2, pp. 53-54, 2011, DOI:10.3970/icces.2011.017.053

Abstract In this paper, we discuss the numerical method for solving the i??rst kind of elliptic variational inequality. We i??rst use the fundamental solution as the basis function to approximate the solution of variational inequality, then we employ the Uzawa's algorithm to determine the free boundary and the solution. Numerical examples are given to testify the efi??ciency of the method. More >

Xue Feng Yao, Yin Ji Ma, Wen Feng Hao, Yu Chao Ke, Dai Ning Fang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.2, pp. 51-52, 2011, DOI:10.3970/icces.2011.017.051

Abstract In this paper, some applications of residual stress measurement in engineering material and structures are introduced. First, some advanced measurement technologies are described like drill hole, residual strain gauge and digital image correlations. Second, the manufacture stresses are explained. Finally, the typical measurement results about the manufacture stress are provided, including: residual stress of integrated composite T-section structures, residual stress of adhesive joint, residual stress of bending tube, residual stress of fiber interface. These results will play an important role in designing and evaluating of advanced material and structure. More >

Younho Cho, Weibin Li, Bin Yang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.2, pp. 49-50, 2011, DOI:10.3970/icces.2011.017.049

Abstract This paper aims at an experimental method for detecting thermal-damages in a tube-like structure using acoustic nonlinear parameter of ultrasonic guided waves. The material nonlinearity of aluminum pipe specimens, which have been subjected to different heat-loading cycles, is measured to characterize the micro-damages. Flexible Polyvinylidene Fluoride (PVDF) comb transducers are used to generate and receive the fundamental and second harmonic waves. The amplitude of the second harmonic wave is extracted from the Fast Fourier Transform (FFT) spectrum of a received signal. The measured relative nonlinear parameter increases monotonically as a function of the propagation distance, and the relative nonlinear parameter… More >

Sheng Sun, Joseph T. Y. Wong, Tong-Yi Zhang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.2, pp. 47-48, 2011, DOI:10.3970/icces.2011.017.047

Abstract Micro/nano structures formed via self-assembly of biological macromolecules, such as DNA and RNA, have potential applications as building units in micro/nano/bio-devices. The self-assembled structures of biological macromolecules can be manipulated by applying electric field. Here we demonstrate such manipulation by using coarse-grained molecular dynamics simulations. Starting from randomly distributed CG DOPE lipids and polarizable water molecules, we studied the self-assembled structures in different hydration levels of lipid (the number of water molecules per lipid) and different strength of external electric fields. When the hydration level of lipid was 24 water per lipid (w/l) or 36 w/l, the self-assembled structures were… More >

Sheng Sun, Joseph T. Y. Wong, Tong-Yi Zhang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.2, pp. 45-46, 2011, DOI:10.3970/icces.2011.017.045

Abstract Lipids in water form different structures (or phases) via self-assembly depending on hydration level of lipid. As the hydration level of lipid increases, the self-assembled structures are micelles, cylinder phase, lamellar phase, and inverted cylinder phase. Lamellar phase or bilayer is the most common structure in cells. Experiments reveal that external electric fields can induce cell membrane poration and fusion, and the technique is widely used to transfer external molecules, such as DNA and drugs, into cells.

By using molecular dynamics simulations, we studied the behaviors of pure phospholipid membrane bilayer in an external electric field, which was applied… More >

Li Jicheng, Lin Li, Wu Di, Li Ximeng

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.2, pp. 43-44, 2011, DOI:10.3970/icces.2011.017.043

Abstract Two kinds of plasma sprayed Cr2O3 coating specimens are tested with electro-mechanical impedance (EMI) method. Quantitative investigation on the relationship between PZT excitation voltage and sensitivity of EMI method is performed in the frequency range of 100-110 kHz, with WK 6500B precision impedance analyzer and high excitation voltage electric impedance measurement system (HEVEIMS). A series of excitation voltage are designed from 0.01 to 15 V. Root mean square deviation (RMSD) of the PZT electric impedance signatures is used as an evaluation indicator. The results show that in the frequency range of 100-110 kHz, the RMSD values are not monotone with… More >