Fausto Pedro García Márquez¹

Structural Durability & Health Monitoring, Vol.6, No.2, pp. 89-100, 2010, DOI:10.3970/sdhm.2010.006.089

Abstract This paper presents a simple graphic method for detecting and classifying faults in point mechanisms based on the study of some statistical parameters of the force and current signals of the point machine. Principal Components Analysis (PCA) employed in order to reduce the number of these parameters. PCA is utilised in this paper for modifying the parameter dataset, and reducing the coordinate system by linear transformation. It is then possible to plot the new coordinate system in 2 or 3 dimensions, where the faults can be detected and identified. In this work most of the More >

Ismet Gölgeleyen¹

CMES-Computer Modeling in Engineering & Sciences, Vol.64, No.1, pp. 71-90, 2010, DOI:10.3970/cmes.2010.064.071

Abstract In this paper, the solvability conditions for an inverse problem for an integro-differential transport equation are obtained and a numerical approximation method based on the finite difference method is developed. A comparison between the numerical solution and the exact solution of the problem is presented. Experimental results show that proposed method is robust to data noises. More >

C.S. Lin, T.C. Chen, C.C. Yu ,M.E. Wu, Y.H. Tu¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.15, No.3, pp. 103-110, 2010, DOI:10.3970/icces.2010.015.103

Abstract Most old apartments in Taiwan lack fire prevention equipment, making fire awareness and escape difficult, as well as timely fire fighting, which leads to increased death tolls from fire incidents. This research utilizes Fire Dynamics Simulator (FDS) software to analyze and simulate the fire accident that occurred in a single old-style five-story apartment on Siu-Lang Road, Chung-Ho City. In this event, many occupant vehicles were parked at the front door of the apartment building or in nearby parking lanes. The fire engine can only drive in after vehicles were cleared from the fire area, a More >

Leela Rakesh¹, Anja Mueller², Pratik Chhetri¹

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.2, pp. 179-202, 2010, DOI:10.3970/fdmp.2010.006.179

Abstract A new material for proton conducting membrane with a higher proton transport but reduced water transport is being developed. The new material optimizes proton channel formation, this reducing water transport at the same time. Different proton transporting groups along with different gas flowing channels are examined as well. To meet the goals we design, synthesize, and simulate various proton transporting groups using MD techniques for faster optimization, which in turn helps to synthesize and test only promising structures in the laboratory. At the same time, computer modeling is used to improve the fuel cell system More >

Arif Amirov¹, Zekeriya Ustaoglu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.54, No.3, pp. 283-300, 2009, DOI:10.3970/cmes.2009.054.283

Abstract We present the solvability of a two space dimensional coefficient inverse problem for a transport-like equation and investigate the approximate solution of this problem with the use of centered difference formulas and a symbolic approximation method. Since this inverse problem is overdetermined, which is the main difficulty in studying of its solvability, it is replaced by a related determined one by using some extension of the class of unknown functions. More >

G.S. Li¹, D. Yao², Y.Z. Wang³, H.Y. Jiang²

CMES-Computer Modeling in Engineering & Sciences, Vol.51, No.1, pp. 53-72, 2009, DOI:10.3970/cmes.2009.051.053

Abstract In this paper, an undisturbed soil-column infiltrating experiment is investigated, and a mathematical model describing multi-components solutes transport behaviors in the column is put forward by combing hydro-chemical analysis with advection dispersion mechanisms, which is a group of advection-dispersion-reaction partial differential equations. Since the model involving six reaction coefficients which can not be obtained directly, an optimal perturbation regularization algorithm of determining these parameters is performed, and numerical simulations under different conditions are carried out. Furthermore, the inversion algorithm is applied to solve the real inverse problem by utilizing the measured breakthrough data. The reconstruction More >

M.J. Galán Moreno, J.J. Sánchez Medina, L. Álvarez Álvarez E. Rubio Royo¹

CMES-Computer Modeling in Engineering & Sciences, Vol.50, No.3, pp. 191-226, 2009, DOI:10.3970/cmes.2009.050.191

Abstract Urban traffic is a key factor for the development of a city. There exist many different approaches facing traffic optimization. In our case we have focused on traffic lights optimization. We have designed and tested a new architecture to optimize traffic light cycle times. The purpose of this research is to demonstrate the good performance of our architecture in a congested scenario. We have simulated several congestion situations for a very large real world traffic network - "La Almozara" in Zaragoza, Spain. Our results seem encouraging in this extreme situation. As we increase the load More >

Mei-Jiau Huang¹, Tung-Chun Tsai¹, Liang-Chun Liu^1,2, Ming-shan Jeng², Chang-Chung Yang²

CMES-Computer Modeling in Engineering & Sciences, Vol.42, No.2, pp. 107-130, 2009, DOI:10.3970/cmes.2009.042.107

Abstract We develop a Monte-Carlo simulator for phonon transport in nanostructured semiconductors, which solves the phonon Boltzmann transport equation under the gray medium approximation. Proper physical models for the phonon transmission/reflection at an interface between two different materials and proper numerical boundary conditions are designed and implemented carefully. Most of all, we take advantage of geometric symmetry that exists in a system to reduce the computational amount. The validity and accuracy of the proposed MC solver was successfully verified via a 1D transient conduction problem and the cross-plane (1D) and in-plane (2D) phonon transport problems associated More >

A. Alke¹, D. Bothe¹

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.4, pp. 345-372, 2009, DOI:10.3970/fdmp.2009.005.345

Abstract We present a computational approach based on the Volume-of-Fluid (VOF) method for simulating the influence of a soluble surfactant on the behavior of two-phase systems with deformable interface. Our approach is applicable to diffusion controlled processes, where the relation between the area-specific excess surfactant concentration on the interface and the volume-specific concentration adjacent to the interface is given by an adsorption isotherm. Main issues of the numerical model are an extended surface transport theorem used for describing the interfacial flux and an iso-surface of the VOF-variable used as a connected approximation for the interface. 3D-simulations More >

J. Roszmann¹, Y.C. Liu¹, S. Dost^1,2, B. Lent¹, S. Grenier³, N. Audet³

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.3, pp. 231-244, 2009, DOI:10.3970/fdmp.2009.005.231

Abstract The article presents the results of a combined numerical and experimental study of the effect of rotating magnetic field on impurity transport in a zone refining system. An impurity (selenium) with a segregation coefficient close to unity was targeted. The three-zone system previously developed was used for experiments and numerical simulations. The numerical simulations were performed for tellurium (Te) and cadmium (Cd) molten zones, but the experiments could only be carried out for the Te-system. More >