Sujuan Guo, Guozheng Kang, Juan Zhang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.4, pp. 121-122, 2011, DOI:10.3970/icces.2011.018.121

Abstract With a newly developed homogenization cyclic constitutive model of particle reinforced metal matrix composites (Guo et al., 2011), the effects of tangent operators, i.e., continuum and algorithmic tangent operators [defined by Doghri and Ouaar (2003)] on the accuracy of the developed meso-mechanical constitutive model to predict the monotonic tensile and uniaxial ratchetting deformation of SiCP/6061Al composites were investigated in this work. The predicted results were obtained by the developed model with the choices of different tangent operators and various magnitudes of loading increments. Some useful accuracy comparison and error analysis on the predicted results were conducted. It is shown that:… More >

Dong-Hoon Kim¹, Sang-Wook Lee¹, Dong-Ik Cheon¹, Hwa-Suk Oh¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.11, No.2, pp. 33-34, 2009, DOI:10.3970/icces.2009.011.033

Abstract In general, accurate attitude information is essential to perform the mission. Two algorithms are well-known to determine the attitude through two or more vector observations. One is deterministic method such as TRIAD algorithm, the other is optimal method such as QUEST algorithm. This paper suggests the idea to improve performance of the TRIAD algorithm and to determine the attitude by combination of different sensors. First, we change the attitude matrix to Euler angle instead of using orthogonalization method and also use covariance in place of variance, then apply an unbiased minimum variance formula for more accurate solutions. We also suggest… More >

G. Papaioannou¹, G. Nianios¹, C. Mitroyiannis¹, S.Tashman², K.H. Yang²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.8, No.1, pp. 7-12, 2008, DOI:10.3970/icces.2008.008.007

Abstract Little is known about in vivo menisci loads and displacements in the knee during strenuous activities. We have developed a method that combines biplane high-speed dynamic radiography (DRSA) and a subject-specific finite element model for studying in vivo meniscal behavior. In a very controlled uniaxial compression loading condition, removing of the pressure sensor from the model can result in relatively large errors in contact and cartilage stress that are not reflected in the change of meniscal displacement. More >

A.Iwasaki¹, K.Yuguchi², A.Todoroki³, Y.Shimamura⁴

The International Conference on Computational & Experimental Engineering and Sciences, Vol.6, No.3, pp. 183-188, 2008, DOI:10.3970/icces.2008.006.183

Abstract The present study is about study on the diagnostic accuracy of the unsupervised damage diagnosis method named SI-F method. For the health monitoring of existing structures, modeling of entire structure or obtaining data sets after creating damage for training is almost impossible. This raises significant demand for development of a low-cost diagnostic method that does not require modeling of entire structure or data on damaged structure. Therefore, the present study proposes a low-cost unsupervised statistical diagnostic method for structural damage detection. The proposed method statistically diagnoses structural condition by means of investigating the change of a response surface which conducts… More >

M.R. Moosavi¹, A. Khelil¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.5, No.4, pp. 211-238, 2008, DOI:10.3970/icces.2008.005.211

Abstract In this paper, a combined formulation of the Finite Volume Method (FVM) and the Meshless Local Petrov-Galerkin (MLPG) is investigated to solve elasto-static problem. Accuracy and computational efficiency study between the combined formulation and the Finite Element Method (FEM) is presented. Some problems of beam under various loading and boundary conditions are analyzed by the proposed method, and the numerical results are compared with analytical solution and result of other numerical method which is obtained by well-known FEM software ABAQUS. The advantages of the FVM combined MLPG (FVMLPG) with respect to the FEM are illustrated. Higher accuracies and computational efficiencies… More >

Zhangzhen Sun¹, Tianhe Xu^1,*, Fan Gao¹, Chunhua Jiang¹, Guochang Xu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.119, No.2, pp. 263-280, 2019, DOI:10.32604/cmes.2019.04425

Abstract Abnormal effects in GPS broadcast ephemerides can have a significant effect on real-time navigation and positioning solutions that use the orbit and clock error data provided by GPS broadcast ephemerides. This paper describes three types of non-integer-hour navigation data in GPS broadcast ephemeris data. Compared with GPST integer hour data, we find that there are two types of data blocks for non-integer-hour navigation containing gross errors with different levels of precision, which is reflected in the user range accuracy (URA) of the broadcast ephemeris. These gross errors can cause large deviations when using the GPS broadcast ephemeris for orbit calculation… More >

D. Yuvaraj¹, M. Sivaram², B. Karthikeyan^3,*, Jihan Abdulazeez⁴

CMC-Computers, Materials & Continua, Vol.59, No.3, pp. 729-739, 2019, DOI:10.32604/cmc.2019.05945

Abstract The perfect image retrieval and retrieval time are the two major challenges in CBIR systems. To improve the retrieval accuracy, the whole database is searched based on many image characteristics such as color, shape, texture and edge information which leads to more time consumption. This paper presents a new fuzzy based CBIR method, which utilizes colour, shape and texture attributes of the image. Fuzzy rule based system is developed by combining color, shape, and texture feature for enhanced image recovery. In this approach, DWT is used to pull out the texture characteristics and the region based moment invariant is utilized… More >

Hao Dong¹, Yufeng Nie^1,2, Zihao Yang¹, Yang Zhang¹, Yatao Wu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.111, No.5, pp. 395-419, 2016, DOI:10.3970/cmes.2016.111.395

Abstract In this paper, we discuss the numerical accuracy of asymptotic homogenization method (AHM) and multiscale finite element method (MsFEM) for periodic composite materials. Through numerical calculation of the model problems for four kinds of typical periodic composite materials, the main factors to determine the accuracy of first-order AHM and second-order AHM are found, and the physical interpretation of these factors is given. Furthermore, the way to recover multiscale solutions of first-order AHM and MsFEM is theoretically analyzed, and it is found that first-order AHM and MsFEM provide similar multiscale solutions under some assumptions. Finally, numerical experiments verify that MsFEM is… More >

I. Kvasnica¹, P. Kvasnica²

CMES-Computer Modeling in Engineering & Sciences, Vol.107, No.6, pp. 447-462, 2015, DOI:10.3970/cmes.2015.107.447

Abstract The issue of simulation of decentralized mathematical models is discussed in the paper. The authors’ knowledge is based on a theory of design of decentralized computer control systems. Their knowledge is gained in the process of designing mathematical models that are simulated. A decomposed control system is required to meet the conditions of observation and control. The methodology of a multi-model design is based on main principles of object orientation such as abstraction, hierarchy, and modularity. Modelling on a parallel architecture has an impact on a simulator system. The system is defined by the equations shown below. An important part… More >

Delfim Soares Jr.¹

CMES-Computer Modeling in Engineering & Sciences, Vol.107, No.3, pp. 223-247, 2015, DOI:10.3970/cmes.2015.107.223

Abstract In this work, an explicit time marching procedure, with solution-adaptive time integration parameters, is introduced for the analysis of hyperbolic models. The proposed technique is conditionally-stable, second-order accurate and it has controllable algorithm dissipation, which locally adapts at each time step, according to the computed solution. Thus, spurious modes can be more effectively dissipated and accuracy is improved. Since this is an explicit time integration technique, the new procedure is very efficient, requiring no system of equations to be dealt with at each time-step. Moreover, the technique is simple and easy to implement, being based just on displacement-velocity relations, requiring… More >