Maghsoudi M.J.,University of Technology Malaysia |
Maghsoudi M.J.,Csp Inc. |
Mohamed Z.,University of Technology Malaysia |
Sudin S.,University of Technology Malaysia |
And 3 more authors.
Mechanical Systems and Signal Processing | Year: 2017
This paper proposes an improved input shaping scheme for an efficient sway control of a nonlinear three dimensional (3D) overhead crane with friction using the particle swarm optimization (PSO) algorithm. Using this approach, a higher payload sway reduction is obtained as the input shaper is designed based on a complete nonlinear model, as compared to the analytical-based input shaping scheme derived using a linear second order model. Zero Vibration (ZV) and Distributed Zero Vibration (DZV) shapers are designed using both analytical and PSO approaches for sway control of rail and trolley movements. To test the effectiveness of the proposed approach, MATLAB simulations and experiments on a laboratory 3D overhead crane are performed under various conditions involving different cable lengths and sway frequencies. Their performances are studied based on a maximum residual of payload sway and Integrated Absolute Error (IAE) values which indicate total payload sway of the crane. With experiments, the superiority of the proposed approach over the analytical-based is shown by 30–50% reductions of the IAE values for rail and trolley movements, for both ZV and DZV shapers. In addition, simulations results show higher sway reductions with the proposed approach. It is revealed that the proposed PSO-based input shaping design provides higher payload sway reductions of a 3D overhead crane with friction as compared to the commonly designed input shapers. © 2017 Elsevier Ltd
Haq S.,GIK Institute |
Uddin M.,GIK Institute |
Uddin M.,Karakoram International University
Engineering Analysis with Boundary Elements | Year: 2011
In this paper, we apply radial basis function (RBF) method for the numerical solution of Kawahara equation. Derivatives of interpolation are used to approximate the spatial derivatives and the temporal derivative approximated by a low order forward difference scheme. Computational experiments are performed for single soliton, two solitons, and three solitons interaction to examine accuracy of the method. The results obtained by the present method are in good agreement with exact solutions and some earlier work in literature. Accuracy of the method is estimated in terms of the error norms L2, L∞, the three invariants, number of nodes in the domain of influence, time step size, parameter dependent, and parameter independent RBFs. © 2010 Elsevier Ltd. All rights reserved.
Hussain S.F.,GIK Institute |
Bashir S.,Bahria University |
Bashir S.,Abu Dhabi University
Knowledge and Information Systems | Year: 2015
In many clustering problems, we have access to multiple sources of data representing different aspects of the problem. Each of these data separately represents an association between entities. Multi-view clustering involves integrating clustering information from these heterogeneous sources of data and has been shown to improve results over a single-view clustering. On the other hand, co-clustering has been widely used as a technique to improve clustering results on a single view by exploiting the duality between objects and their attributes. In this paper, we propose a multi-view clustering setting in the context of a co-clustering framework. Our underlying assumption is that similarity values generated from the individual data can be transferred from one view to the other(s) resulting in a better clustering of the data. We provide empirical evidence to show that this framework results in a better clustering accuracy than those obtained from any of the single views, tested on different datasets. © 2015 Springer-Verlag London
Haq S.,GIK Institute |
Ishaq M.,GIK Institute
International Journal of Heat and Mass Transfer | Year: 2012
An analytic approximate procedure, called optimal homotopy asymptotic method (OHAM) is considered for the solution of strongly nonlinear differential equations arising in heat transfer. Two particular applications are chosen: convecting-radiating cooling of a lumped system with variable specific heat and fins with temperature dependent surface heat flux. The effectiveness of the method, which is independent of the small parameter, is investigated by comparing the results obtained with the exact and the results already present in the literature. © 2012 Elsevier Ltd. All rights reserved.
Khan M.,Quaid-i-Azam University |
Azam N.A.,GIK Institute
Security and Communication Networks | Year: 2015
This article deals with an algorithm for the generation of impregnable substitution boxes (S-box). The proposed scheme involves the application of right translation and Gray codes over the original Advanced Encryption Standard (AES) S-box. Regular representation of Galois field GF(28) is used to produce the translational effect in the AES S-box. The translated AES S-box is then subjected to Gray codes for the enhancement in their algebraic complexity. The proposed scheme results 256 different cryptographically strong S-boxes. Several tests such as non-linearity, bit independence, strict avalanche, linear approximation and differential approximation, algebraic complexity, correlation and histogram are implemented on every newly generated S-box to analyze their resistance against computational attacks. Furthermore, the newly generated S-boxes are compared with the existing well-known S-boxes. The simulation results indicate that the resistance of proposed S-boxes against computational attacks including linear, interpolation, differential and algebraic attacks approaches to the optimal values. © 2014 John Wiley & Sons, Ltd.
Idrees M.,GIK Institute |
Islam S.,CIIT |
Haq S.,GIK Institute |
Islam S.,University of Peshawar
Computers and Mathematics with Applications | Year: 2010
In this paper, axisymmetric flow of two-dimensional incompressible fluids is studied. The Optimal Homotopy Asymptotic Method (OHAM) is applied to derive a solution of the reduced fourth-order nonlinear boundary value problem. For comparison, the same problem is also solved by the Perturbation Method (PM), the Homotopy Perturbation Method (HPM)  and the Homotopy Analysis Method (HAM) . OHAM is parameter free and provides better accuracy at lower order of approximation. Moreover we can easily adjust and control the convergence region. As a result it is concluded that the new technique, OHAM, shows fast convergence, simplicity of application and efficiency. © 2010 Elsevier Ltd. All rights reserved.
Haq S.,GIK Institute |
Ishaq M.,GIK Institute
Ocean Engineering | Year: 2014
In this work, an approximate method called Optimal Homotopy Asymptotic Method (OHAM) is proposed and implemented for the numerical solution of Whitham-Broer-Kaup (WBK) equations with blow-up and periodic solutions. Results obtained through OHAM are compared with the exact as well as with the results available in the literature. It was revealed that only second-order OHAM solutions are sufficient to achieve the desired accuracy in comparison to the higher order solutions of the methods we have made comparison with. © 2014 Elsevier Ltd.
Manan A.,University of Peshawar |
Iqbal Y.,University of Peshawar |
Qazi I.,GIK Institute
Journal of Physics: Conference Series | Year: 2010
Ceramics with layered perovskite structures are widely used as microwave dielectric components in the telecommunication industry. The potential of Sr5Nb4TiO17 as a possible Pb-and Bi-free alternative for microwave applications was investigated. Sr5Nb 4TiO17 was prepared by mixed oxide route. Calcined and sintered samples were characterized by X-ray diffraction and scanning electron microscopy. Samples sintered at temperatures ≤1400°C comprised mainly Sr5Nb4TiO17 along with a small amount of Sr2Nb2O7 as a second phase. Single phase dense Sr5Nb4TiO17 with relatively good electrical properties formed at 1450°C whereas Sr6Nb4Ti 2O20 formed as second phase at temperatures ≥1500°C. SEM showed an increase in the grain size and variation in grain morphology with increase in the sintering temperature. Further work is underway to optimize the processing and hence the properties of Sr5Nb 4TiO17. © 2010 IOP Publishing Ltd.
Hussain I.,Quaid-i-Azam University |
Azam N.A.,Quaid-i-Azam University |
Azam N.A.,GIK Institute |
Shah T.,Quaid-i-Azam University
Optics and Laser Technology | Year: 2014
In this article, an optical image encryption algorithm with an information hiding technique is presented. In this algorithm, a secret image is implanted into the cover image. After that the stego-image is encrypted with the help of double random phase encoding algorithm and chaotic substitution box transformation. Also, we present a comparative analysis between images "without substitution box transformation", "with substitution box transformation" and "with chaotic substitution box transformation". Security test shows that image transform with chaotic substitution box transformation is better than others. Furthermore we analyze proposed encryption scheme with other existing techniques and come to close that our algorithm is better than others. © 2014 Elsevier Ltd.
Abid M.,GIK Institute |
Parvez S.,GIK Institute |
Nash D.H.,University of Strathclyde
International Journal of Pressure Vessels and Piping | Year: 2013
In this study, the effect of different tip angles (30°, 60°, 90° and 120°) on the arc and weld pool behavior is analyzed in 2mm and 5mm arc lengths with tilted (70°) torch. Arc temperature, velocity, current density, heat flux and gas shear are investigated in the arc region and pool convection and puddle shapes are studied in the weld pool region. The arc temperature at the tungsten electrode is found the maximum with sharp tip and decreases as the tip angle increases. The arc temperature on the anode (workpiece) surface becomes concentrated with increase in tip angle. The arc velocity and gas shear stress are observed large with sharp tip and decreasing as the tip angle increases. Current density on the anode surface does not change with tip angle and observed almost the same in all the tip angles in both 2mm and 5mm arc lengths. Heat flux due to conduction and convection is observed more sensitive to the tip angle and decreases as the tip angle increases. The electromagnetic force is slightly observed increasing and the buoyancy force is observed slightly decreasing with increase in tip angle. Analyzing each driving force in the weld pool individually shows that the gas drag and Marangoni forces are much stronger than the electromagnetic and buoyancy forces. The weld pool shape is observed wide and shallow in sharp and narrow and deep in large tip angle. Increasing the arc length does not change the weld pool width; however, the weld pool depth significantly changes with arc length and is observed deep in short arc length. The arc properties and weld pool shapes are observed wide ahead of the electrode tip in the weld direction due to 70° torch angle. Good agreement is observed between the numerical and experimental weld pool shapes. © 2013 Elsevier Ltd.