Yanling Bai^1,*, Feng Liu²

FDMP-Fluid Dynamics & Materials Processing, Vol.15, No.4, pp. 307-319, 2019, DOI:10.32604/fdmp.2019.07833

Abstract Levenberg-Marquardt (LM) algorithm is applied for the optimization of the heat transfer of a batch reactor. The validity of the approach is verified through comparison with experimental results. It is found that the mathematical model can properly describe the heat transfer relationships characterizing the considered system, with the error being kept within ±2°C. Indeed, the difference between the actual measured values and the model calculated value curve is within ±1.5°C, which is in agreement with the model assumptions and demonstrates the reliability and effectiveness of the algorithm applied to the batch reactor heat transfer model. Therefore, the present work provides… More >

Longling Fan^1,§, Jing Yao^2,§, Chun Yang³, Di Xu², Dalin Tang^1,4*

Molecular & Cellular Biomechanics, Vol.13, No.1, pp. 33-55, 2016, DOI:10.3970/mcb.2016.013.044

Abstract Modeling ventricle active contraction based on in vivo data is extremely challenging because of complex ventricle geometry, dynamic heart motion and active contraction where the reference geometry (zero-stress geometry) changes constantly. A new modeling approach using different diastole and systole zero-load geometries was introduced to handle the changing zero-load geometries for more accurate stress/strain calculations. Echo image data were acquired from 5 patients with infarction (Infarct Group) and 10 without (Non-Infarcted Group). Echo-based computational two-layer left ventricle models using one zero-load geometry (1G) and two zero-load geometries (2G) were constructed. Material parameter values in Mooney-Rivlin models were adjusted to match… More >

A. Prieto-Moreno¹, L.D.Tavares Câmara², O. Llanes-Santiago¹, A. J. Silva Neto²

CMES-Computer Modeling in Engineering & Sciences, Vol.106, No.6, pp. 441-462, 2015, DOI:10.3970/cmes.2015.106.441

Abstract This work deals with a statistical approach to the uncertainty propagation analysis when estimating the kinetic mass transfer parameters used to model a chromatographic column in the Simulated Moving Bed. The chromatographic column modeling was performed using the new front velocity approach. The uncertainty propagation analysis of operational factors intervening in the chromatographic process to estimated parameters was made using the response surface methodology. The application of the factorial experimental design allowed us to establish those operational factors showing a greater influence on continuous chromatography. Besides, the chromatographic regions, where factors cause a greater output variation as well as their… More >

C. J. Reddy¹

CMES-Computer Modeling in Engineering & Sciences, Vol.5, No.5, pp. 455-462, 2004, DOI:10.3970/cmes.2004.005.455

Abstract This paper presents an efficient algorithm to evaluate multi-spectral and multi-angular monostatic radar cross section (RCS) of large objects with very fine increments. The technique is based on the combination of Model Based Parameter Estimation (MBPE) method with hybrid frequency domain formulations. A general approach to formulation of MBPE is presented along with a similar approach called the Asymptotic Waveform Evaluation (AWE). Various numerical examples are presented for multi-spectral response calculations using method of moments (MoM) and the hybrid Finite Element-MoM technique in conjunction with MBPE. Example application of MBPE for hybrid MoM-Physical Optics approach for multi-angular calculations is also… More >

M. Irízar, L. D. Câmara, A. J. Silva Neto, O. Llanes

CMES-Computer Modeling in Engineering & Sciences, Vol.54, No.1, pp. 1-14, 2009, DOI:10.3970/cmes.2009.054.001

Abstract Modeling of Chromatography allows a better understanding and development of new techniques to be applied at industrial level, although it's relatively complex. The models of this process are represented by systems of partial differential equations with non linear parameters difficult to estimate generally, which constitutes an inverse problem. In general there aren't analytical solutions and therefore numerical methods should be used for their direct solutions. Frequently typical boundary conditions are considered, but it's convenient to study different approaches for those. Evolutionary Computation has been used successfully in many problems of diverse areas for searching in complex spaces. Considering previous works… More >

F. Daghia¹, W. Hasan¹, L. Nobile¹, E. Viola^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.39, No.1, pp. 1-28, 2009, DOI:10.3970/cmes.2009.039.001

Abstract In this paper, a finite element model has been developed for analysing the flexural vibrations of a uniform Timoshenko beam-column on a two-parameter elastic foundation. The beam was discretized into a number of finite elements having four degrees of freedom each. The effect of end springs was incorporated in order to identify the end constraints. \newline The procedure for identifying geometric and mechanical parameters as well as the end restraints of a beam on two-parameter elastic foundation is based on experimentally measured natural frequencies from dynamic tests on the structure itself. \newline An iterative statistical identification method, based on the… More >