Iris recognition has very high recognition accuracy in comparison with many other biometric features. Many algorithms have been proposed to improve the performance of iris recognition. This paper proposes an iris recognition algorithm in which a set of iris images of a given eye are fused to generate a final template using the most consistent feature data. Features consistency weight matrix is determined according the noise level presented in the considered images. Such an algorithm has the capability of reducing the amount of data storage and accelerate the matching process. Simulation studies are made to test the validity of the proposed algorithm. The results obtained ensure the superior of such algorithm over any other one.
This research presents and analyzes the problem of sedimentation at water intake of Rowd El-Farag pump station using a dimensional computational model, CCHE2D. A study reach with a length of 1.53km from 7.785 to 9.31km from El-Roda gauging station was selected. The pump station is located at 8.63km from El-Roda gauging station. The study shows there is a significant morphological change in this reach due to the long study period and two hydraulic Structures (Imbaba and Rowd El-Farag Bridges). Moreover, the different alternatives for sediment control are discussed such as: dikes on the western side of the river at different locations or dredging the study area at different levels 14 and 12.5 (1 and 2.5m respectively) below minimum water level. Finally, the research recommended the using of dredging as a sustainable solution for sediment control at Water Intake of Rowd El-Farag Pump Station although this solution is an expensive solution.
In this paper an ABC transient model of the three phase induction motor is developed that depends on self- and mutual inductance calculations based on accurate finite element analysis (FEA). This model can represent both healthy and broken bars’ conditions. The effects of that type of fault on the stator current, rotor bar currents distribution, the forces exerted on the rotor bars, the motor speed and motor torque are studied. It was observed that broken bar faults will cause fluctuations in the stator peak current and in the motor speed and torque. It was found that the asymmetry in the rotor bar currents will lead to asymmetrical distribution of the radial and tangential forces affecting the bars. The asymmetry in the tangential forces causes the fluctuations in the motor torque, while the asymmetry in the radial forces will increase the mechanical stresses on the rotor shaft.
The effect of both of the positioning and the thickness of soft clay layer on 3D-building resting on piled raft has not received much attention. Herein, a computer program ASTNII is developed by the author in order to examine the behavior of a layer of soft clay with different hypothetical positions and thicknesses. Composed coefficient technique is employed in ASTNII to save time. Many cases of different positions and thicknesses are diagnosed to cover practical cases.Based on finite element method, ASTNII is used to analyze three dimensional buildings on piled raft in a parametric study. That study is developed to include two different structural models of square and rectangular shapes. Different cases are analyzed to reflect the effect of changing of both of position and thickness of soft clay on the system. Discussions on the numerical results are performed and conclusions are drawn.
This paper introduces two new complex instructions over the application with specific instruction set processor. For the MCS-51 family, utilizing a reserved bit, and the unused machine code “A5h” we can modify the conventional instruction set architecture (ISA) and develop two macro instructions for data manipulation. One of them is to move a block of data from specific memory locations to any other memory locations, while the other developed instruction is to obtain maximum byte-value within a group of 8-bytes and load it into the Accumulator. There are two basic steps to achieve such developments, step-1; at which we modify the architecture of the conventional microcontroller 8051 using hardware description language HDL. In the second step we modify the instruction set architecture (ISA) of μC 8051. Such development improves the performance of the μC including fast execution time, decrease machine code size, so decrease storage requirements and provide low power consumption.
The aim of this paper is to present an efficient numerical procedure for solving the Abel’s integral equation of the first and second kind and compare it with block-pulse functions (BPFs) method. The proposed method is based on Chebyshev wavelets approximation. This method transforms the integral equation into the matrix equation. The advantages of Chebyshev wavelets are that the values of μk and M are adjustable as well as it can yield more accurate numerical solutions than piecewise constant orthogonal functions on the solution of integral equations. The uniform convergence theorem and accuracy estimation are derived and numerical examples show the validity and the wide applicability of the Chebyshev wavelets approach.
The objective of this paper is to study the effects of Hall current and radiation absorption on MHD free convection mass transfer flow of a micropolar fluid in a rotating frame of reference. A uniform magnetic field acts perpendicular to the porous surface in which absorbs micropolar fluid with a constant suction velocity. The entire system rotates about the axes normal to the plate with uniform angular velocity Ω. The dimensionless governing equations for this investigation are reduced to a system of linear differential equations using regular perturbation method, and equations are solved analytically. The influence of various flow parameters of the flow field has been discussed and explained graphically. The present study is of immediate interest in geophysical, cosmically fluid dynamics, medicine, biology, and all those processes which are greatly embellished by a strong magnetic field with a low density of the gas.
The problem of unsteady, two-dimensional, laminar, boundary-layer flow of a viscous, incompressible, electrically conducting and heat-absorbing Rivlin–Ericksen flow fluid along a semi-infinite vertical permeable moving plate in the presence of a uniform transverse magnetic field and thermal buoyancy effect is considered. The plate is assumed to move with a constant velocity in the direction of fluid flow while the free stream velocity is assumed to follow the exponentially increasing small perturbation law. Time-dependent wall suction is assumed to occur at the permeable surface. The dimensionless governing equations for this investigation are solved analytically using two-term harmonic and non-harmonic functions. The obtained analytical results reduced to previously published results on a special case of the problem. Numerical evaluation of the analytical results is performed and some graphical results for the velocity and temperature profiles within the boundary layer are presented. Skin-friction coefficient, Nusselt numbers are also discussed with the help of the graphs.
A future gas plant is to be located at the beach adjacent to Edko Town in the eastern part of Abu Qir Bay. The proposed site comprises a low elevation sandy beach and lagoon. One of the main aspects of this project is to study the possibility of land reclamation using fill material from offshore sources rather than onshore quarries. Another aspect is the method of lagoon drainage and its environmental impacts. This paper presents some challenges associated with the design phase of the project and presents the feasibility and preliminary environmental impact assessments of lagoon drainage, dredging and land reclamation. The study indicated that use of dredging spoils is attractive as it is cost effective, requires less time and has less overall environmental impacts. The environmental assessment methodology used in this study can be applied as a preliminary assessment of land reclamation projects at coastal areas.
The problem of propagation of acceleration waves in an unsteady inviscid non-ideal gas under the influence of magnetic field is investigated. The characteristic solution to the problem in the neighbourhood of leading characteristics has been determined. An evolution equation governing the behaviour of acceleration waves has been derived. It is shown that a linear solution in the characteristic plane exhibits non-linear behaviour in physical plane. The effect of magnetic field on the formation of shock in non-ideal gas flow with planar and cylindrical symmetry is analysed. It is noticed that all compressive waves terminate into a shock wave. Further, we also compare/contrast the nature of solution in ideal and non-ideal magnetogasdynamic regime.
Water is a limited resource that needs sustainable management, which aims to develop and protect it. Without a proper management, water will become a constraining factor in the socioeconomic development of Egypt.
Giving information on the economic value of water enable decision makers to take informed choices on water allocation to face the growing demands for all uses and drawing its sustainable future in agricultural and water policies. The current paper aims to assist decision makers in developing new cropping patterns considering the supply and demand aspects based on the efficient utilization of the water resources. It has proposed a cropping pattern which can increase the economic value of irrigation water from 0.88 LE/CM to 0.92 LE/CM. It can also decrease the gap between the national production and the imports, and increase self sufficiency of the main agricultural crops.
Many Internet multicast applications such as videoconferencing, distance education, and online simulation require to send information from a source to some selected destinations. These applications have stringent Quality-of-Service (QoS) requirements that include delay, loss rate, bandwidth, and delay jitter. This leads to the problem of routing multicast traffic satisfying QoS requirements. The above mentioned problem is known as the QoS constrained multicast routing problem and is NP Complete. In this paper, we present a swarming agent based intelligent algorithm using a hybrid Ant Colony Optimization (ACO)/Particle Swarm Optimization (PSO) technique to optimize the multicast tree. The algorithm starts with generating a large amount of mobile agents in the search space. The ACO algorithm guides the agents’ movement by pheromones in the shared environment locally, and the global maximum of the attribute values are obtained through the random interaction between the agents using PSO algorithm. The performance of the proposed algorithm is evaluated through simulation. The simulation results reveal that our algorithm performs better than the existing algorithms.
This work represents the main acoustical design phases for the new lecture auditorium in the Faculty of Law, Ain Shams University, Cairo/Egypt. The work also discusses some of the architectural details that were used and have a direct effect on the acoustical environment inside the auditorium. The work compares finally among field measurements (that were recorded after the construction in the unoccupied auditorium), the values expected during the acoustic design phase (utilizing ODEON ver. 4.2, assuming the occupied case), and the optimum values for speech intelligibility indicators that were considered in this work (T20, D50, STI, LAeq, and the background noise). Field measurements that were recorded utilizing MLSSA system showed that the finishing materials used successfully fulfilled a good level of speech intelligibility in the auditorium. The estimated reverberation time T20-EOC for the occupied room (based on the measured unoccupied T20-M) was close to the optimum especially in mid and high frequency bands. The measured D50 (unoccupied) was found to be within its acceptable range. The measured STI value (unoccupied) was “Fair, 0.49”. The measurements of LAeq indicated the uniformity of the acoustical field in the room. The noticed problem was a relatively high background noise (NC-40) due to the utilization of natural ventilation which directly contradicts the principles of room isolation.
This paper presents an improved adaptive fuzzy logic speed controller for a DC motor, based on field programmable gate array (FPGA) hardware implementation. The developed controller includes an adaptive fuzzy logic control (AFLC) algorithm, which is designed and verified with a nonlinear model of DC motor. Then, it has been synthesised, functionally verified and implemented using Xilinx Integrated Software Environment (ISE) and Spartan-3E FPGA. The performance of this controller has been successfully validated with good tracking results under different operating conditions.
This paper presents a decoupled control strategy using time-varying sliding surface-based sliding-mode controller for speed control of permanent magnet synchronous motor (PMSM). The decoupled method provides a simple way to achieve asymptotic stability for a PMSM by dividing the system into two subsystems electrical and mechanical systems. The simulation results for PMSM are presented to demonstrate the effectiveness and robustness of the method. Comparing this controller with pulse width modulation (PWM) controller for the same motor.
A mathematical model is conducted for the unsteady magnetohydrodynamic viscous, incompressible free convective flow of an electrically conducting Newtonian fluid over an impulsively-started semi-infinite vertical plate adjacent to saturated porous medium in the presence of appreciable thermal radiation heat transfer and chemical reaction of first order taking transverse magnetic field into account. The fluid is assumed optically thin gray gas, absorbing-emitting radiation, but a non-scattering medium. The governing non-linear partial differential equations are non-dimensionalized and are solved by an implicit finite difference scheme of Crank–Nicholson type. It is found that, increasing magnetic parameter serves to decelerate the flow, but increased temperatures and concentration values. An increase in the porosity parameter (K) is found to escalate the local skin friction (τx), Nusselt number (Nux) and the Sherwood number (Shx). Applications of the model include fundamental magneto-fluid dynamics, MHD energy systems and magneto-metallurgical processing for aircraft materials.
To deal with non-stationary and quasi-stationary signals, wavelet transform has been used as an effective tool for the time-frequency analysis. In the recent years, wavelet transform has been used extensively for feature extraction in noisy speech recognition. These filters have the benefit of having frequency bands spacing similar to the auditory Equivalent Rectangular Bandwidth (ERB) scale. Central frequencies of ERB are equally distributed with the frequency response of the human cochlea.
This paper deals with the speaker-independent Automatic Speech Recognition (ASR) system for continuous speech. This Hidden Markov Model (HMM) based ASR system was developed for English using recordings of four regions taken from TIMIT database. A new set of features were derived using wavelet packet transform’s multi-resolution capabilities and having an advantage of ERB filter based on the human cochlea. New set of wavelet features have shown significant improvements in the noisy environment, especially at low SNR values.
In recent papers the solution of Linear and Nonlinear Fredholm Integral Equations was introduced using the Adomian Decomposition Method (ADM). For cases that evaluation of integrals analytically are impossible the decomposition method can not be applied. In this paper a discretized version of the Adomian Decomposition Method is introduced and this method is called Discrete Adomian Decomposition Method (DADM). DADM arises when the quadrature rules are used to approximate the definite integrals which can not be computed analytically. The DADM gives the numerical solution at nodes used in the quadrature rules.
In this paper, we present the Legendre wavelets based method for the solution of homogeneous and nonhomogeneous advection problems. The properties of Legendre wavelets are used to reduce the problem to the solution of system of algebraic equations. The function approximation has been chosen in such a way so as to calculate the connection coefficients in an easy manner. Also the convergence analysis and error estimation for the proposed function approximation through the truncated series have been discussed and approved with the exact solution. Illustrative examples are discussed to demonstrate the validity and applicability of the technique.
This paper is focused on local scour downstream of adverse stilling basins where a submerged wall jet issued from a sluice gate. Experiments were conducted in a wide range of Froude numbers, grain sizes, tailwater depths, and stilling basin slopes. The results showed that the scour profiles at any bed slope follow shape similarity. However, the longitude evolution of scour profiles and the volume of eroded materials were increasing in accordance with slope of basin. A polynomial equation was derived to define the non-dimensional profiles under different slopes. The time evolution of scour hole dimensions and the equilibrium state were defined. It was found that under a specific condition of sediment grain size, approaching Froude number, the length and slope of adverse basin, the scour depth at the downstream of adverse basin, initially increases with tailwater depth, and after reaching its maximum value decreases to a constant value. It was also observed that the maximum depth of scour hole was decreased as the length and slope of stilling basin increased, whereas the longitudinal dimensions of the hole were increased. It was found that the maximum depth of scour hole occurs at the vicinity of side walls with slight decrease in the centerline. Finally, a power equation was expressed to fully define the dimensions of scour hole, time scale and geometry of sluice gate.
In this paper, a dynamic load-balancing scheme is developed for implementation in an agent-based distributed system. Load balancing is achieved via agent migration from heavily loaded nodes to lightly loaded ones. The credit based concept is used for the dual objective of: (1) the selection of candidate agents for migration, and (2) the selection of destination nodes. This represents an elaboration of previous research work aimed at the selection of agents only. Multiple linear regression is used to achieve our dual objective. A complexity analysis for the proposed system operation is performed, the complete operation is O(n2) where n is the number of agents on the local host.The proposed system is implemented using JADE (Java Agent DEvelopment Framework), the multiple linear regression operation is performed using R Tool. The experimental results show a modified system operation in terms of reduced user’s query response time, by implementing agent load balancing.
Recently, environmental protection has a great concern in Egypt where recycling of increased demolition debris has become a viable option to be incorporated into roads applications. An extensive laboratory program is conducted to study the feasibility of using recycled concrete aggregate (RCA) mixed with traditional limestone aggregate (LSA) which is currently being used in base or subbase applications in Egypt. Moreover, the influence of mixture variables on the mechanical properties of cement treated recycled aggregate (CTRA) is investigated. Models to predict the compressive and tensile strengths based on mixture parameters are established. The results show that the adding of RCA improves the mechanical properties of the mixture where the unconfined compressive strength (UCS) is taken as an important quality indicator. Variables influencing the UCS such as cement content, curing time, dry density play important roles to determine the performance of CTRA.
In the present paper, the experimental system under consideration is a rotating cylinder of 50 mm diameter placed in still air. The numerical calculations are carried out by using a finite volume method based computational fluid dynamics solver FLUENT. The results of the heat transfer are characterized in terms of the non-dimensional parameters: Nusselt number (Nu), Reynolds number (Re), and Grashof number (Gr). The experimental measurements are carried out for Reynolds number range of 1880–6220 and Grashof numbers range of 14,285–714,285, while the numerical calculations are carried out for Reynolds number range of 0–100,000 and Grashof numbers range of 100–1,000,000. The effects of rotation on the heat transfer characteristics are presented in terms of the isotherm patterns, streamlines, local and the average Nusselt numbers. The results correlated as: Nu = 0.022Re0.821 which compares very well with the data available for air in published works.
This research aimed to investigate the armor layer stability of the new breakwater of El Dikheila Port. An undistorted physical hydraulic model with a scale of 1:39.73 was employed as a tool to simulate the existing and the proposed new breakwaters. The physical model was constructed in the wave basin of the Hydraulics Research Institute (HRI), Delta Barrages, Egypt. The armor layer of the new breakwater was tested with regular and random placement for the trunk and the roundhead. The damage occurs with wave height of 1.2Hs at the head and the trunk sections with the random placement case. The model results showed that regular placing exhibited higher stability for initial damage and gradual damage progression than the random placement of the armor units.
This paper investigates feeder reconfiguration in balanced and unbalanced networks and presents an efficient method to optimize practical distribution systems by means of simultaneous reconfiguration and distributed generation (DG) allocation. A precise and robust load flow algorithm is applied and a composite multi-objective function is formulated to solve the problem which includes: 1. power loss saving, 2. voltage profile, 3. voltage unbalance, and 4. current unbalance of the system. The genetic algorithm (GA) is utilized to search for optimal solution. Results show significant reduction in power loss and number of voltage violations. Moreover, in unbalanced cases, ability of proposed method in three-phase balancing is demonstrated.
The aim of this work is to evaluate the machinability of Pb-free brasses with Si from 1% to 4 wt%, which were prepared using Cu 60/Zn 40 and Cu 80/Si 20 Pb-free master alloys. Machinability of the investigated alloys is tested based on cutting force, tool wear, surface roughness, and chip type. In the 1 wt% Si alloy, which exhibits maximum strength, the maximum cutting force is measured and undesirable continuous chip type is produced, while tool wear and machined surface roughness have the lowest values. Increasing the silicon content from 1% to 4%, results in increasing the tool wear by 140%, machined surface roughness by 25%, while the chip type changed from continuous to discontinuous type, and the cutting force was reduced by 50%. Machinability results are correlated with the alloy mechanical properties and with the phases present in the microstructure.
Bedsa is one of the districts in Dahshour that lays south west of Cairo and suffered from liquefaction during October 1992 earthquake, Egypt. The soil profile consists of alluvial river Nile deposits mainly sandy mud with low plasticity; the ground water is shallow. The earthquake hypocenter was 18 km far away with local magnitude 5.8; the fault length was 13.8 km, as recorded by the Egyptian national seismological network (ENSN) at Helwan. The analysis used the empirical method introduced by the national center for earthquake engineering research (NCEER) based on field standard penetration of soil. It is found that the studied area can liquefy since there are saturated loose sandy silt layers at depth ranges from 7 to 14 m. The settlement is about 26 cm. The probability of liquefaction ranges between 40% and 100%. The presence of impermeable surface from medium cohesive silty clay acts as a plug resisting and trapping the upward flow of water during liquefaction, so fountain and spouts at weak points occurs. It is wise to use point bearing piles with foundation level deeper than 14 m beyond the liquefiable depth away from ground slopes, otherwise liquefaction improving techniques have to be applied in the area.
The behavior of an amperometric biosensor based on parallel substrates conversion for steady-state condition has been discussed. This analysis contains a non-linear term related to enzyme kinetics. Simple and closed form of steady-state analytical expressions of concentrations and density of the biosensor current are derived. A Homotopy perturbation method (HPM) is employed to solve the simultaneous non-linear reaction diffusion equations. Furthermore, in this work the numerical solution of the problem is also reported using Matlab program. The analytical results are compared with the numerical results and found to be good in agreement. The provided analytical solution is very simple and more efficient to understand the behavior of the system.
In this paper, a mathematical model for gas sensing thin film semiconductor at an internal diffusion limitation for non-steady-state conditions is discussed. The model is based on diffusion equations containing a linear term related to the reaction processes. Analytical expressions for concentrations are derived using Laplace transformation. The gas sensitivity for both actual and equivalent models has been reported for all the values of reaction parameters such as rate constant and film thickness. Furthermore, in this work a complex inversion formula is employed to solve the boundary value problem. An excellent agreement with simulation data is observed. The dependence of sensitivity on temperature, film thickness and time are discussed for both actual and equivalent models.
The aim of this article is to introduce a new analytical and approximate technique to obtain the solution of time-fractional Navier–Stokes equation in a tube. This proposed technique is the coupling of Adomian decomposition method (ADM) and Laplace transform method (LTM). We have consider the unsteady flow of a viscous fluid in a tube in which, besides time as one of the dependent variable, the velocity field is a function of only one space coordinate. A good agreement between the obtained solutions and some well-known results has been demonstrated. It is shown that the proposed method robust, efficient, and easy to implement for linear and nonlinear problems arising in science and engineering.
In this paper, we obtain analytical solutions of homogeneous time-fractional Gardner equation and non-homogeneous time-fractional models (including Buck-master equation) using q-Homotopy Analysis Method (q-HAM). Our work displays the elegant nature of the application of q-HAM not only to solve homogeneous non-linear fractional differential equations but also to solve the non-homogeneous fractional differential equations. The presence of the auxiliary parameter h helps in an effective way to obtain better approximation comparable to exact solutions. The fraction-factor in this method gives it an edge over other existing analytical methods for non-linear differential equations. Comparisons are made upon the existence of exact solutions to these models. The analysis shows that our analytical solutions converge very rapidly to the exact solutions.
An analytical solution of MHD free convective, dissipative boundary layer flow past a vertical porous surface in the presence of thermal radiation, chemical reaction and constant suction, under the influence of uniform magnetic field which is applied normal to the surface is studied. The governing equations are solved analytically using a regular perturbation technique. The expressions for velocity, temperature and concentration fields are obtained. With the aid of these, the expressions for the coefficient of skin friction, the rate of heat transfer in the form of Nusselt number and the rate of mass transfer in the form of Sherwood number are derived. Finally the effects of various physical parameters of the flow quantities are studied with the help of graphs and tables. It is observed that the velocity and concentration increase during a generative reaction and decrease in a destructive reaction. The same observed to be true for the behavior of the fluid temperature. The presence of magnetic field and radiation diminishes the velocity and also the temperature.
Local scour downstream stilling basins is so complex that it makes it difficult to establish a general empirical model to provide accurate estimation for scour depth. Lack estimation of local scour can endanger to stability of hydraulic structure and can cause risk of failure. This paper presents Gene expression program (GEP) and artificial neural network (ANNs), to simulate local scour depth downstream hydraulic structures. The experimental data is collected from the literature for the scour depth downstream the stilling basin through a trapezoidal channel. Using GEP approach gives satisfactory results compared with artificial neural network (ANN) and multiple linear regression (MLR) modeling in predicting the scour depth downstream of hydraulic structures.
The ever increasing demand and depletion of fossil fuels had an adverse impact on environmental pollution. The selection of appropriate source of biodiesel and proper blending of biodiesel plays a major role in alternate energy production. This paper describes an application of hybrid Multi Criteria Decision Making (MCDM) technique for the selection of optimum fuel blend in fish oil biodiesel for the IC engine. The proposed model, Analytical Network Process (ANP) is integrated with Technique for Order Performance by Similarity to Ideal Solution (TOPSIS) and VlseKriterijumska Optimizacija I Kompromisno Resenje (in Serbian) (VIKOR) to evaluate the optimum blend. Evaluation of suitable blend is based on the exploratory analysis of the performance, emission and combustion parameters of the single cylinder, constant speed direct injection diesel engine at different load conditions. Here the ANP is used to determine the relative weights of the criteria, whereas TOPSIS and VIKOR are used for obtaining the final ranking of alternative blends. An efficient pair-wise comparison process and ranking of alternatives can be achieved for optimum blend selection through the integration of ANP with TOPSIS and VIKOR. The obtained preference order of the blends for ANP-VIKOR and ANP-TOPSIS are B20 > Diesel > B40 > B60 > B80 > B100 and B20 > B40 > Diesel > B60 > B80 > B100 respectively. Hence by comparing both these methods, B20 is selected as the best blend to operate the internal combustion engines. This paper highlights a new insight into MCDM techniques to evaluate the best fuel blend for the decision makers such as engine manufactures and R& D engineers to meet the fuel economy and emission norms to empower the green revolution.
The repeated operation of the Anti-Lock Braking System (ABS) causes accumulation of structural damages in its different subsystems leading to reduction in their functional life time. This paper proposes a Fuzzy Logic based Life-Extending Control (FLEC) system for increasing the service life of the ABS. FLEC achieves significant improvement in service life by the trade-off between satisfactory dynamic performance and safe operation. The proposed FLEC incorporates structural damage model of the ABS. The model utilizes the dynamic behavior of the ABS and predicts the wear rates of the brake pads/disc. Based on the predicted wear rates, the proposed fuzzy logic controller modifies its control strategy on-line to keep safe operation leading to increase in service time of the ABS. FLEC is fine tuned via genetic algorithm and its effectiveness is verified through simulations of emergency stops of a passenger vehicle model.
A mathematical model of the movement of the shoreline in a sedimentary ocean basin is discussed. The model includes space–time fractional derivative in Caputo sense and variable latent heat term. An approximate solution of the problem is obtained by Adomian decomposition method and the results thus obtained are compared graphically with an exact solution of integer order (β = 1, α = 1). Three particular cases, the standard diffusion, the time-fractional and the space-fractional diffusions are also discussed. The model and solution are generalization of previous works.
In this paper, a modified harmonic balance method based an analytical technique has been developed to determine approximate solutions for a strongly nonlinear oscillator with a discontinuous term which is arising from the motion of rigid rod on the surface without slipping. Usually, a set of nonlinear algebraic equations is solved in this method. However, analytical solutions of these algebraic equations are not always possible, especially in the case of a large oscillation. We have been compared the solution results of this method with the numerical solution in order to validate the approach and assess the accuracy of the solutions has been demonstrated and discussed. We found that, a second order modified harmonic balance method works very well for the whole range of initial amplitudes. The advantage of the using method is its simple procedure and gives almost similar results in comparison with the exact solution.
A dynamical model of HIV infection of CD4+ T cells is solved numerically using an approximate analytical method so-called the differential transform method (DTM). The solution obtained by the method is an infinite power series for appropriate initial condition, without any discretization, transformation, perturbation, or restrictive conditions. A comparative study between the present method, the classical Euler’s and Runge–Kutta fourth order (RK4) methods is also carried out.
In this paper, we have developed an efficient shifted second kind Chebyshev wavelets based approximation method to water quality assessment model problem. The governing equation of the uniform flow model is one-dimensional convection diffusion equation (CDE) with variable coefficients. This water quality model requires the calculation of the substance dispersion given the water velocity in the channel. To the best of our knowledge, until now there is no rigorous wavelet solution has been reported for the water quality model problem. The shifted second kind Chebyshev wavelet method (CWM) for assessment of the chemical oxygen demand (COD) in a river is considered. Some numerical examples are presented to demonstrate the validity and applicability of the method.
The aim of this work is to study the Legendre wavelets for the solution of boundary value problems for a class of higher order Volterra integro-differential equations using function approximation. The properties of Legendre wavelets together with the Gaussian integration method are used to reduce the problem to the solution of nonlinear algebraic equations. Also a reliable approach for convergence of the Legendre wavelet method when applied to a class of nonlinear Volterra equations is discussed. Illustrative examples have been discussed to demonstrate the validity and applicability of the technique and the results obtained by Legendre wavelet method is very nearest to the exact solution. The results demonstrate reliability and efficiency of the proposed method.
Local scour downstream of hydraulic structures due to hydraulic jump is considered one of the tedious and complicated problems facing their stability. Throughout this paper, an experimental study was conducted to study the effect of using different spaced corrugated aprons on the downstream local scour due to submerged jump. Sixty runs were carried out in a horizontal rectangular flume to determine the optimal corrugation wavelength which minimizing the scour. A case of flat apron included to estimate the influence of corrugated aprons on scour holes dimensions. Two types of non-cohesive soil were used. Experiments were performed for a range of Froude numbers between 1.68 and 9.29. The results showed that using spaced triangular corrugated aprons minimize the scour depth and length of fine sand by average percentage of 63.4% and 30.2%, respectively and for coarse sand by 44.2% and 20.6% in comparing with classical jump.
This paper highlights a novel strategy for online Arabic text recognition using a hybrid Genetic Algorithm (GA) and Harmony Search algorithm (HS). The strategy is divided into two phases: text segmentation using dominant point detection, and recognition-based segmentation using GA and HS. At first, the pre-segmentation algorithm uses a modified dominant point detection algorithm to mark a minimal number of points which defines the text skeleton. The generated text skeleton from this process is expressed as directional vector, using 6-directional model, to minimize the effect of character body on segmentation process. Then, GA and HS algorithms are used as recognition-based segmentation phase for text and character recognition respectively. For the segmentation based recognition, binary GA is used to explore different combinations of segmentation points which gives the best score, while HS is integrated inside the GA segmentation to explore the best character score produced from matching the character with different characters stored in the database. In order to initially calibrate and test the system, a locally collected text dataset was used that contains 4500 Arabic words. The algorithm scored a 93.4% successful word recognition rate. Finally, the system was tested on the benchmark ADAB dataset 2 consist of 7851 Arabic words and it scored a successful recognition rate in the range of 94–96%.
Twitter, an online micro blogs, enables its users to write and read text-based posts known as “tweets”. It became one of the most commonly used social networks. However, an important problem arises is that the returned tweets, when searching for a topic phrase, are only sorted by recency not relevancy. This makes the user to manually read through the tweets in order to understand what are primarily saying about the particular topic. Some strategies were developed for summarizing English micro blogs but Arabic micro blogs summarization is still an active research area. This paper presents a machine learning based solution for summarizing Arabic micro blogging posts and more specifically Egyptian dialect summarization. The goal is to produce short summary for Arabic tweets related to a specific topic in less time and effort. The proposed strategy is evaluated and the results are compared with that obtained by the well-known multi-document summarization algorithms including; SumBasic, TF-IDF, PageRank, MEAD, and human summaries.
In the present article we have discussed the blood flow analysis of Prandtl fluid model in tapered stenosed arteries. The governing equations for considered model are presented in cylindrical coordinates. Perturbation solutions are constructed for the velocity, impedance resistance, wall shear stress and shearing stress at the stenosis throat. Attention has been mainly focused to the analysis of embedded parameters in converging, diverging and non-tapered situations. Streamlines have been plotted at the end of the article for considered arteries. It is observed that due to increase in Prandtl fluid parameters, the stenosis shape and maximum height of the stenosis the velocity profile decreases.
One of the available tests that can be used to evaluate concrete sulfate resistance is USBR4908. However, there are deficiencies in this test method. This study focuses on the ANN as an alternative approach to evaluate the sulfate expansion. Three types of cement combined with FA or SF, along with variable W/B were study by USBR4908. ANN model were developed by five input parameters, W/B, cement content, FA or SF, C3A, and exposure duration; output parameter is determined as expansion. Back propagation algorithm was employed for the ANN training; a Tansig function was used as the nonlinear transfer function. It was clear that the ANN models give high prediction accuracy. In addition, The engineer can avoid the use of the borderline 2.5–5% C3A content in severe sulfate environments and borderline 6–8% C3A content in moderate sulfate environments, specially with W/B ratio greater than 0.45.
Two-sided assembly lines are common industrial practice in the assembly of large-sized products. In this paper a Genetic Algorithm (GA) is developed to solve the two-sided assembly line balancing problem. The developed GA specifies a new method for generating the initial population. It applies a hybrid crossover and a modified scramble mutation operators. A proposed station oriented procedure is adopted for assigning tasks to mated-stations. It specifies the side of the Either tasks based on proposed side assignment rules rather than assigning them randomly. These rules are effective especially in large problems. The proposed method of generating the initial population is able to generate feasible solution in different areas of the search space. The applied genetic operators are able to preserve the feasibility of all solutions throughout all the developed generations. The proposed GA is able to find the optimum and near optimum solutions within a limited number of iterations.
Voltage instability is considered as a main threat to stability, security, and reliability in the modern power systems. Prediction of voltage stability limit of multi-bus system through its two-bus equivalent model is a hot topic of the research in the field of power system operation and control. This paper presents a novel method to assess voltage stability status using a unique two-bus π-network equivalent derived with OPF solution of the actual system at different operating conditions. As the FACTS controllers are now an ineluctable part of power system, this paper considers an SVC and a TCSC in OPF formulation to assess voltage stable states of any interconnected power system in terms of its reduced two-bus integrated π-equivalent system. Simulation results for a practical power system establish that the proposed methodology is highly promising to assess voltage stability in a better way as compared to existing series equivalent model.
Multi Criteria Analysis (MCA) describes any structured approach used to determine overall preferences among alternative options, where options accomplish certain or several objectives. The flood protection of properties is a highly important issue due to the damage, danger and other hazards associated to it to human life, properties, and environment. To determine the priority of execution of protection works for any project, many aspects should be considered in order to decide the areas to start the data collection and analysis with. Multi criteria analysis techniques were tested and evaluated for the purpose of flood risk assessment, hydro-morphological parameters were used in this analysis. Finally a suitable technique was chosen and tested to be adopted as a mark of flood risk level and results were presented.
The paper presents the application of interval mathematics as a new method to, rigorously, address uncertainties associated with designing substation earthing system. While several methods exist to determine the important factors for personnel safety in and around substations such as earth resistance, different potentials of substation earthing grid, these methods usually require data which may be uncertain in nature. To account for such uncertainties the interval mathematics is developed with the integration of input parameters’ uncertainties, in interval format, into the governing standard expressions mentioned on IEEE STD 80-2000. The effects of uncertain inputs within the proposed model are examined for various assumed levels of overall uncertainties. To assess the relative contribution of each uncertain input, an interval sensitivity analysis is carried out. Successful implementation of the proposed method is described for the design and configuration arrangement of a 115/13 kV substation earthing rectangular grid with ground rods system.