Darrell W. Pepper¹, Xiuling Wang²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.13, No.1, pp. 15-22, 2009, DOI:10.3970/icces.2009.013.015

Abstract A meshless method for simulating indoor contaminant dispersion within buildings and rooms has been developed. The approach utilizes the advantages of the meshless method by distributing collocation points and different order radial basis functions according to the computational domain and evolving numerical solution. The numerical scheme yields fast convergence and high accuracy necessary for providing quick assessments of contamination transport within enclosures. More >

AnteBilić¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.13, No.1, pp. 13-14, 2009, DOI:10.3970/icces.2009.013.013

Abstract Using several popular first-principles packages for materials modeling the nature of the cubic lattice of barium zirconate has been investigated. The evaluated vibrational spectra typically exhibit an extended and prominent dynamical instability. The instability manifests through imaginary frequency optical modes along the whole R-M edge of the Brillouin zone. The experimentally observed simple cubic structure is found to be dynamically unstable against an antiferro-distortive transformation. The computations predict an orthorhombic crystal structure of the material, only slightly distorted from the cubic lattice, with an eight times larger unit cell and alternate ZrO₆ octahedra slightly rotated in More >

N. J. Lee, C.R. Welch¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.13, No.1, pp. 11-12, 2009, DOI:10.3970/icces.2009.013.011

Abstract Carbon nanotubes have significant potential as the basis for super infrastructure material. The shear modulus of carbon nanotube ensembles is relatively low, comparable to graphite, as the carbon nanotubes interact via weak van der Waals forces. Unmodified, their intermolecular interactions are insufficient to take full advantage of the extraordinarily high strengths predicted for carbon nanotube-based fibers. Thus, a key to their use in high-strength materials is developing strong bonds between these molecules. In this study, we examine the potential development of covalent bonds between carbon nanotube pairs cross-bonded by proton bombardment using molecular dynamics simulation. More >

Sutthinane Nilbuaklee¹, Chanyut Kolitawong¹, Banpot Horbanluekit^1,2

The International Conference on Computational & Experimental Engineering and Sciences, Vol.13, No.1, pp. 4-10, 2009, DOI:10.3970/icces.2009.013.004

Abstract The purpose of this research is to determine fracture effects of vulcanize elastomer at various thickness to width ratios under opening mode fracture mechanics. The J-integral values from finite element method are compared with those from experiment. In this research, fracture tests perform under Single Edge Notch Tensile (S.E.N.T) tests using the multiple-specimen method. Compare to the experimental data, the numerical results are acceptable at the deep crack length, i.e. high crack length to width ratio. The k values from the 3-D numerical calculation show that thin sheet is dominated by plane stress state, but thick sheet More >

Soojin Cho¹, Jin-Hak Yi², Chung-Bang Yun¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.12, No.4, pp. 151-152, 2009, DOI:10.3970/icces.2009.012.151

Abstract The bridges are exposed to severe operational and environmental loadings, such as traffic, wind, and earthquake during their life time. Continuous exposure to such severe loadings may lead to structural damage requiring costly repair/retrofit and even may result in an unexpected disaster, which emphasizes the importance of assessing the current condition of bridges. From the last decade, FE model updating techniques based on the bridge dynamic characteristics are emerged to evaluate the current condition of bridges quantitatively. Most of the model updating techniques basically utilize an optimization process with an objective function built up by… More >

R.M. Reddy¹, B.N. Rao²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.12, No.4, pp. 149-150, 2009, DOI:10.3970/icces.2009.012.149

Abstract Probabilistic fracture mechanics (PFM) blends the theory of fracture mechanics and the probability theory provides a more rational means to describe the actual behavior and reliability of structures. However in PFM, the fracture parameters and their derivatives are often required to predict the probability of fracture initiation and/or instability in cracked structures. The calculation of the derivatives of fracture parameters with respect to load and material parameters, which constitutes size-sensitivity analysis, is not unduly difficult. However, the evaluation of response derivatives with respect to crack size was a challenging task, since it requires shape sensitivity… More >

Janja Kramer, Renata Jecl, Leopold Skerget

The International Conference on Computational & Experimental Engineering and Sciences, Vol.12, No.4, pp. 147-148, 2009, DOI:10.3970/icces.2009.012.147

Abstract A numerical study of double diffusive natural convection in porous media due to opposing buoyancy forces is reported, using the Boundary Domain Integral Method (BDIM). There have been several reported studies dealing with natural convection in porous media, mainly because of its importance in several industrial and technological applications. Less attention, however, has been dedicated to the so-called double diffusive problems, where density gradients occur due to the effects of combined temperature and concentration buoyancy. The current investigation is focused on the special problem, where the thermal and solutal buoyancy forces are opposing each other.
The… More >

Nucu Antohi¹, Eugen Merticaru², Emil Budescu²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.12, No.4, pp. 145-146, 2009, DOI:10.3970/icces.2009.012.145

Abstract In the theory of coaching an important role belongs to the factorial management. The art of planning, controlling and evaluating the main factors (physical, technical, tactical, psychological and theoretical) gives to the coach the real value of his work. The individualization of these factors turn the process of coaching into a complex activity which in nowadays has teamwork finality: to achieve the performance. At the same time, the manager of the whole process of coaching has the whole responsibility of the task.
All the sports have specialists who make decisions to improve the process of coaching,… More >

F. Keissarian¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.12, No.4, pp. 137-144, 2009, DOI:10.3970/icces.2009.012.137

Abstract In this paper, a new image compression technique is proposed in which variable block size technique is adopted, using quadtree decomposition, for coding images at low bit rates. The proposed algorithm decomposes the host image into blocks of variable sizes according to histogram analysis of the block residuals. Variable block sizes are then encoded at different rates based on their visual activity levels. To preserve edge integrity, a high-detail block is coded by a set of parameters associated with the pattern appearing inside the block. The use of these parameters at the receiver together with More >

Arif Amirov¹, Fikret Gölgeleyen¹, Ayten Rahmanova²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.12, No.4, pp. 125-136, 2009, DOI:10.3970/icces.2009.012.125

Abstract This paper has two purposes. The first is to prove the existence and uniqueness of the solution of an inverse problem for the general linear kinetic equation with a scattering term. The second one is to develop a numerical approximation method for the solution of this inverse problem for two dimensional case using finite difference method. More >