Liliane Cruz Gomes de Souza Santos^1*, Eliane Ayres², Flávio Renato de Góes Padula¹

Journal of Renewable Materials, Vol.5, No.3-4, pp. 307-312, 2017, DOI:10.7569/JRM.2017.634121

Abstract In this study, bamboo powder and/or hollow glass microspheres were added to thermoplastic cassava starch in order to overcome its drawbacks. The composites were characterized by scanning electron microscopy (SEM), tensile testing, water contact angle measurement and X-ray diffractometry (XRD), in addition to their thermal properties. The mechanical strength of the composites showed a general decline with increasing bamboo powder content while the water contact angles increased up to 15% of bamboo powder content (% w/w dry starch). The addition of hollow glass microspheres provides an optimal balance between hydrophobicity and mechanical strength. The results pointed to improved properties that… More >

Dilson E. Rassier^*

Molecular & Cellular Biomechanics, Vol.6, No.4, pp. 229-242, 2009, DOI:10.3970/mcb.2009.006.229

Abstract When activated skeletal muscles are stretched at slow velocities, force increases in two phases: (i) a fast increase, and (ii) a slow increase. The transition between these phases is commonly associated with the mechanical detachment of cross-bridges from actin. This phenomenon is referred to asforce enhancement during stretch. After the stretch, force decreases and reaches steady-state at levels that are higher than the force produced at the corresponding length during purely isometric contractions. This phenomenon is referred to asresidual force enhancement.The mechanisms behind the increase in force during and after stretch are still a matter of debate, and have physiological… More >

Dhanjoo N. Ghista^1,2, Liang Zhong², Leok P.Chua², Eddie Y-K Ng², Soo T.Lim³, Ru S. Tan³, TerranceS-J Chua³

Molecular & Cellular Biomechanics, Vol.2, No.4, pp. 217-234, 2005, DOI:10.3970/mcb.2005.002.217

Abstract Background: In this paper, the left ventricle (LV) is modeled as a cylinder with myocardial fibers located helically within its wall. A fiber is modeled into myocardial structural units (MSUs); the core entity of each MSU is the sarcomeric contractile element. The relationship between the sarcomere unit's contractile force and shortening velocity is expressed in terms of the LV model's wall stress and deformation, and hence in terms of the monitored LV pressure and volume. Then, the LV systolic performance is investigated in terms of a mechatronic (excitation-contraction) model of the sarcomere unit located within the LV cylindrical model wall.… More >

A. Parassuram^1,*, P. Somasundaram¹

CMES-Computer Modeling in Engineering & Sciences, Vol.117, No.2, pp. 169-187, 2018, DOI:10.31614/cmes.2018.01720

Abstract A continuous-time Model Predictive Controller was proposed using Kautz function in order to improve the performance of Load Frequency Control (LFC). A dynamic model of an interconnected power system was used for Model Predictive Controller (MPC) design. MPC predicts the future trajectory of the dynamic model by calculating the optimal closed loop feedback gain matrix. In this paper, the optimal closed loop feedback gain matrix was calculated using Kautz function. Being an Orthonormal Basis Function (OBF), Kautz function has an advantage of solving complex pole-based nonlinear system. Genetic Algorithm (GA) was applied to optimally tune the Kautz function-based MPC. A… More >

G. R. Venkatakrishnan^1,*, R. Rengaraj², S. Salivahanan³

CMES-Computer Modeling in Engineering & Sciences, Vol.115, No.1, pp. 25-45, 2018, DOI:10.3970/cmes.2018.115.025

Abstract A new and efficient Grey Wolf Optimization (GWO) algorithm is implemented to solve real power economic dispatch (RPED) problems in this paper. The nonlinear RPED problem is one the most important and fundamental optimization problem which reduces the total cost in generating real power without violating the constraints. Conventional methods can solve the ELD problem with good solution quality with assumptions assigned to fuel cost curves without which these methods lead to suboptimal or infeasible solutions. The behavior of grey wolves which is mimicked in the GWO algorithm are leadership hierarchy and hunting mechanism. The leadership hierarchy is simulated using… More >

Munish Kumar¹, Simpel Rani Jindal²

CMES-Computer Modeling in Engineering & Sciences, Vol.113, No.2, pp. 195-202, 2017, DOI:10.3970/cmes.2017.113.201

Abstract Grading of writers in perspective of their handwriting is a challenging task owing to various writing styles of different individuals. This paper presents a framework for grading of Devanagari writers in perspective of their handwriting. This framework of grading can be useful in conducting the handwriting competitions and then deciding the winners on the basis of an automated process. Selecting the set of features is a challenging task for implementing a handwriting grading system of particular language. In this paper, curvature features, namely, parabola curve fitting and power curve fitting have been considered for extracting the vital information of writers,… More >

T. V. Viknesh¹, V. Manik,an

CMES-Computer Modeling in Engineering & Sciences, Vol.113, No.1, pp. 109-116, 2017, DOI:10.3970/cmes.2017.113.107

Abstract The working of Canonical switching cell (CSC) converter was studied and its equivalent circuit during ON and OFF states were obtained. State space model of CSC converter in ON and OFF states were developed using the Kirchhoff laws. The state space matrices were used to construct the transfer functions of ON & OFF states. The step response of the converter was simulated using MATLAB. The step response curve was obtained using different values of circuit components (L, C1, C2 and RL)and optimized. The characteristic parameters such as rise time, overshoot, settling time, steady state error and stability were determined using… More >

R. Shamsoddini, N. Aminizadeh1, M. Sefid

CMES-Computer Modeling in Engineering & Sciences, Vol.105, No.3, pp. 209-230, 2015, DOI:10.3970/cmes.2015.105.209

Abstract In this study, an improved weakly compressible Smoothed Particle Hydrodynamics method is introduced and applied for investigation of the non- Newtonian power-law fluid flow which is induced by motion of a square cylinder. The method is based on a predictor-corrector scheme and pressure velocity coupling to overcome the non-physical fluctuations of WCSPH. The numerical method is also supported by the corrective tensors and shifting algorithm. The results are validated against the well known test cases and benchmark data. The square motion is tested in various Reynolds numbers for various power law indices. The results show that the drag coefficient increases… More >

Guoqing Yang¹, Baotong Li^2,3, Yang Wang², Jun Hong²

CMES-Computer Modeling in Engineering & Sciences, Vol.103, No.4, pp. 251-279, 2014, DOI:10.3970/cmes.2014.103.251

Abstract Mechanical behaviors arising at the contact interface largely depend on its surface topographies, particularly when it comes to rough surfaces. A numerical simulation based on an appropriate characterization of rough surfaces especially in terms of three dimensional can be of great significance when it comes to capturing the deformation patterns of micro-scale contacts. In this paper, a simple and practical scheme is developed to generate 3D rough surfaces and to analyze and evaluate the contact characteristics. Firstly amplitude and spatial statistical characterizations of asperities are introduced to avert from the redundancy of topography data caused by traditional measuring methods. A… More >

Max de Castro Magalhaes¹

CMES-Computer Modeling in Engineering & Sciences, Vol.89, No.4, pp. 263-281, 2012, DOI:10.3970/cmes.2012.089.263

Abstract The main objective is to develop a 'hybrid' numerical method for predicting sound power radiated from honey-comb panels and analyze the sensitivity and variability of it to different boundary conditions. The honey-comb panels are mainly used on the aerospace, mechanical and civil engineering design. The method used herein is a combination of the Finite Element Method and the Jinc Function Approach. The original contribution of this paper is therefore to show the sensitivity of sound power radiated from a honey-comb panel using a 'hybrid' method which is simple and efficient on tackling sound radiation problems for complex orthotropic panels, especially… More >