V.G. Kozlov^1,2, A.A. Ivanova³, P. Evesque¹

FDMP-Fluid Dynamics & Materials Processing, Vol.2, No.3, pp. 203-210, 2006, DOI:10.3970/fdmp.2006.002.203

Abstract Sedimentation of granular matter in a vertical channel filled with a viscous liquid and subject to longitudinal translational vibration is studied, starting froma compact suspension. A new vibrational effect is foundexperimentally and described theoretically; it is the formation of blocks (with a relatively high density) of sedimenting granular matter with stable lower and upper horizontal demarcations and a sharp density discontinuity. Owing to this phenomenon the sedimentation velocity of such granular matter is reduced. A new theoreticalmodel based on viscous vibrational particle interactionin the limit of concentrated suspensions is elaborated, assuming particle-particle attraction in direction parallel tovibration and particle-particle repulsion… More >

Nesrine EBRAHIM¹, Eman EHSAN², Eman Abd EL GHANY², Dina SABRY³, Ashraf SHAMAA⁴

BIOCELL, Vol.43, No.1, pp. 21-28, 2019, DOI:10.32604/biocell.2019.06111

Abstract The neonatal hypoxic–ischemic encephalopathy (HIE) is an important cause of neurological morbidity and mortality in neonates. Cell therapy is considered a promising method for treating severe neurological disorders such as this one. Stem cells have the capacity for self-renewal and differentiation into certain cell lineages. The present study was aimed to find out the most beneficial route of bone marrow-derived mesenchymal stem cells (BMSCs) administration for the attenuation of experimentally induced HIE in neonatal rats. Sixty neonatal rats were divided randomly into four groups. Group 1: control group. Group 2: rats were exposed to bilateral ligation of cephalic arteries. Group… More >

Leone Corradi¹, Francesco Genna²

CMES-Computer Modeling in Engineering & Sciences, Vol.4, No.3&4, pp. 381-396, 2003, DOI:10.3970/cmes.2003.004.381

Abstract A critical comparison of several Finite Element models is presented, with reference to the analysis of the stress and strain states around a tooth or a fixed dental implant. Such an analysis, if performed on a full, three-dimensional geometry of the jaw-tooth/dental implant system, requires significant computational resources, and it is therefore often done on simplified models, whose validity can be questionable. On the other side, the use of simplified models is adequate --- almost mandatory --- when detailed results are needed, or when geometrical and material nonlinearities, as well as other complicating factors, are to be taken into account.… More >

G. Suguinoshita¹, C. H. Silva¹, M. A. Luersen^{1, *}

CMES-Computer Modeling in Engineering & Sciences, Vol.117, No.1, pp. 59-71, 2018, DOI:10.31614/cmes.2018.01777

Abstract This paper describes a study of the effects of graphite nodule characteristics on a subsurface crack in austempered ductile iron (ADI). A representative specimen of ADI, subjected to sliding contact load, is modeled using finite elements aiming to obtain the shear stress intensity factor (K_II). The parameters varied were (i) the nodule diameter (two different values were considered), (ii) the distance between the nodule and the tip of the crack and (iii) the position of the load relative to the tip of the crack. The results of the numerical simulations show that the smaller diameter nodule has a larger influence… More >

C. Gopinath^{1, *}, M. Rajvikram¹

CMES-Computer Modeling in Engineering & Sciences, Vol.115, No.3, pp. 359-386, 2018, DOI: 10.3970/cmes.2018.06143

Abstract This research paper proposes a single phase fifteen level inverter for a grid connected PV system. The proposed inverter is also called cascaded asymmetric multilevel inverter. By adopting appropriate hybrid modulation technique improved output voltage is obtained with minimum number of power electronic switches. By reducing the number of gate triggering circuits of the switches, the size and power consumption of the driving circuits can be reduced. The total harmonic distortion of the output of the inverter is improved by this inverter. The proposed inverter developed by cascading a full bridge inverter with modified H bridge multilevel inverter. The validity… More >

Haitao Liao¹

CMES-Computer Modeling in Engineering & Sciences, Vol.115, No.2, pp. 233-262, 2018, DOI: 10.3970/cmes.2018.01004

Abstract A hybrid method combined the reduced Sequential Quadratic Programming (SQP) method with the harmonic balance method has been developed to analyze the characteristics of mode localization and internal resonance of nonlinear bladed disks. With the aid of harmonic balance method, the nonlinear equality constraints for the constrained optimization problem are constructed. The reduced SQP method is then utilized to deal with the original constrained optimization problem. Applying the null space decomposition technique to the harmonic balance algebraic equations results in the vanishing of the nonlinear equality constraints and a simple optimization problem involving only upper and lower bound constraints on… More >

V. Venkatachalam^{1, *}, D. Prabhakaran¹

CMES-Computer Modeling in Engineering & Sciences, Vol.114, No.3, pp. 321-334, 2018, DOI:10.3970/cmes.2018.114.321

Abstract This paper presents, using Lyapunov-Krasovskii functional technique combined with reciprocal convex lemma is considered for a networked control temperature control system with additive time-varying-delays. In the stability analysis, a new LK functional is assumed, and take the time-derivative of the (LK) functional, using reciprocal convex combination technique was employed to obtain less conservative stability criteria. Finally, the proposed stability analysis culminates into a stability criterion in the LMI (linear matrix inequalities) framework. The results obtained are in accordance with the theoretically obtained in the temperature control system and they are closer to the standard benchmark temperature-control system. More >

Kuntao Ye^1,*, Yan Luo¹, Yingtao Jiang^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.114, No.3, pp. 261-276, 2018, DOI:10.3970/cmes.2018.114.261

Abstract Torsional micromirror devices have been widely used in micro displays, RF switches, optical communications, and optical coherence tomography systems. In order to study the stability of electrostatically driven torsional micromirror system with double bottom plates and two voltage sources, a dimensionless, two degrees of freedom (2-DoF) dynamic model was constructed. Governed by the dimensionless phase space model equation, the pull-in and bifurcation phenomena were analyzed using the Hamiltonian method and numerical simulation. In particular, the influence of the damping coefficient and the torsion-bending coupling effect on the phase trajectory was investigated. Furthermore, the conditions that can lead to pull-in were… More >

Dongkai Shen^1,2,+, Qian Zhang¹, Yixuan Wang^1,*, Huiqing Ge^3,*, Zujin Luo^4,+

CMES-Computer Modeling in Engineering & Sciences, Vol.114, No.2, pp. 117-139, 2018, DOI:10.3970/cmes.2018.114.117

Abstract A pressure controlled mechanical ventilator with an automatic secretion clearance function can improve secretion clearance safely and efficiently. Studies on secretion clearance by pressure controlled systems show that these are suited for clinical applications. However, these studies are based on a single lung electric model and neglect the coupling between the two lungs. The research methods applied are too complex for the analysis of a multi-parameter system. In order to understand the functioning of the human respiratory system, this paper develops a dimensionless mathematical model of double-lung mechanical ventilation system with a secretion clearance function. An experiment is designed to… More >

Zeng Xiangfu, Ma Shaopeng, Ma Qinwei, Chen Pengwan

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 111-112, 2011, DOI:10.3970/icces.2011.017.111

Abstract In order to measure the attitude parameters of the projectile, a high-speed 3-dimensional digital image correlation (H3D-DIC) system is designed and constructed. In the H3D-DIC system, two high-speed cameras are used to capture the images of the projectile from two different directions and the 3-dimensional coordinates of the markers painted on projectile are obtained by processing the images using stereovision techniques. Because of the difference on the resolution of the two cameras, the images captured are with different magnification. Therefore, a new correlation program, in which the parameter of pixel size is also included in the correlation schedule, is designed… More >