Crow Algorithm for Irrigation Management: A Case Study

Water Resources Management - This study employed a new evolutionary algorithm namely, the crow algorithm (CA), to optimize reservoir operation and minimize irrigation water deficit. Comprehensive...     

Numerical Study of the Dynamics and Structure of a Partial Dam-Break Flow Using the VOF Method

Water Resources Management - This paper aims to evaluate the effects of the opening width of a dam site on the evolution of partial dam-break waves over a fixed dry bed. The volume of fluid (VOF)...     

Fast and efficient intra mode decision for HEVC,based on dual-tree complex wavelet

Multimedia Tools and Applications - The new video coding standard, High Efficiency Video Coding (HEVC) uses up to 33 angular intra modes to achieve better coding efficiency in intra coding. While...     

An adaptive nonmonotone truncated Newton method for optimal control of a class of parabolic distributed parameter systems

A black-box method using the finite elements, the Crank–Nicolson and a nonmonotone truncated Newton (TN) method is presented for solving optimal control problems (OCPs) governed by partial differential equations (PDEs). The proposed method finds the optimal control of a class of linear and nonlinear parabolic distributed parameter systems with a quadratic cost functional. To this end, the piecewise linear finite elements method and the well-known Crank–Nicolson method are used for discretizing in space and in time, respectively. Afterwards, regarding the implicit function theorem (IFT), the optimal control problem is transformed into an unconstrained nonlinear optimization problem. Considering that in a gradient-based method for solving optimal control problems, the evaluations of gradients and Hessians of the cost functional is important, hence, an adjoint technique is used to evaluate them effectively. In addition, to make a globalization strategy, we first introduce an adaptive nonmonotone strategy which properly controls the degree of nonmonotonicity and then incorporate it into an inexact Armijo-type line search approach to construct a more relaxed line search procedure. Finally, the obtained unconstrained nonlinear optimization problem is solved by utilizing the proposed nonmonotone truncated Newton method. Results gained from the new offered method compared with existing methods show that the new method is promising.     

QoS decomposition for service composition using genetic algorithm

Recently, a lot of research has been dedicated to optimizing the QoS-aware service composition. This aims at selecting the optimal composed service from all possible service combinations regarding user's end-to-end quality requirements. Existing solutions often employ the global optimization approach, which does not show promising performance. Also, the complexity of such methods extensively depends on the number of available web-services, which continuously increase along with the growth of the Internet. Besides, the local optimization approaches have been rarely utilized, since they may violate the global constraints. In this paper, we propose a top-down structure, named quality constraints decomposition (QCD) here, to decompose the global constraints into the local constraints, using the genetic algorithm (GA). Then the best web service for each task is selected through a simple linear search. In contrast to existing methods, the QCD approach mainly depends on a limited set of tasks, which is considerably less complex, especially in the case of dynamically distributed service composition. Experimental results, based on a well-known data set of web services (QWSs), show the advantages of the QCD method in terms of computation time, considering the number of web services.     

Modeling and simulation of a horizontal pulsed sieve-plate extraction column using axial dispersion model

In this research, the impact of pulsation intensity and phase flow rates on the volumetric overall mass transfer coefficients based on the continuous phase (K_oca) and the axial dispersion coefficients of phases in a horizontal pulsed sieve-plate column has been investigated using axial dispersion model. The toluene-acetone-water and butyl acetate-acetone-water systems with acetone transfer in both directions were used. In this study, the flow regime transition from pseudo-dispersion regime to emulsion regime has been characterized. Two new correlations have been proposed for prediction of K_oca and E_c.     

Analog/RF Study of Self-aligned In<Subscript>0.53</Subscript>Ga<Subscript>0.47</Subscript>As MOSFET with Scaled Gate Length

This study presents the impact of gate length scaling on analog and radio frequency (RF) performance of a self- aligned multi-gate n-type In_0.53Ga_0.47As metal oxide semiconductor field effect transistor. The device is fabricated using a self-aligned method, air-bridge technology, and 8 nm thickness of the Al₂O₃ oxide layer with different gate lengths. The transconductance-to-normalized drain current ratio (g _m/I _D) method is implemented to investigate analog parameters. Moreover, g _m and drain conductance (g _D) as key parameters in analog performance of the device are evaluated with g _m/I _D and gate length variation, where g _m and g _D are both showing enhancement due to scaling of the gate length. Early voltage (V _EA) and intrinsic voltage gain (A _V) value presents a decreasing trend by shrinking the gate length. In addition, the results of RF measurement for cut-off and maximum oscillation frequency for devices with different gate lengths are compared.     

Adaptive beamforming algorithm with increased speed and improved reliability for smart antennas

In this paper, a novel adaptive beamforming algorithm has been proposed which can be used for tracking the subscribers of a smart antenna in a wide angle spread environment. It can be adapted for arbitrary variations in both eigenvalues and eigenvectors of the autocorrelation matrix of received signal which is mostly the case for moving subscribers’ environment. Moreover, it uses one adaptive module which is less than two adaptive modules of previous works and leads to a high speed at least two times more than previous works.     

The impact of side walls on the MHD flow of a second-grade fluid through a porous medium

The magnetohydrodynamic flow through a porous medium of a second-grade fluid between two side walls induced by an infinite plate that exerts an accelerated shear stress to the fluid over an infinite plate is examined. Expressions for velocity and shear stress are determined with the help of integral transforms. In the absence of side walls, all the solutions that have been obtained are reduced to those corresponding to the motion over an infinite flat plate. The Newtonian solutions are also obtained as limiting case of the general solution. Finally, influence of magnetic and porosity parameter is graphically highlighted.