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Integral equations play a crucial role in many scientific and engineering problems, though solving them is often challenging. This paper addresses the solution of multi-dimensional systems of mixed Volterra-Fredholm integral equations (SMVF-IEs) by means of a Legendre-Gauss-Lobatto collocation method. The one-dimensional case is addressed first. Afterwards, the method is extended to two-dimensional linear and nonlinear SMVF-IEs. Several numerical examples reveal the effectiveness of the approach and show its superiority in comparison to other alternative techniques for treating SMVF-IEs. [ABSTRACT FROM AUTHOR]

The passive feature of natural convection encourages continuous investigation on this field. This research work studies the natural convection inside a cavity of wavy vertical surfaces, including a heat source block standing on the base of cavity. The employed liquid is a hybrid water–Cu–Al 2 O 3 nanofluid. The vertical wavy surfaces are fixed at low temperature, while the heat source remains constant at a higher temperature. The Galerkin finite element method is applied to obtain the numerical solutions. Besides the common visualization tools, the heatlines tool is used in this paper as well. It is found from the outcomes that the Nusselt number is purely proportional to the length of the heat source. In addition, the hybrid water–Cu–Al 2 O 3 nanofluid exhibits a higher Nusselt number than that corresponding to a pure water and as well as other regular nanofluids. The percentages of the average heat transfer gained by the hybrid nanofluid at ϕ = 0.02 are 13.7% and 5% higher than those for pure water and other nanofluids. [ABSTRACT FROM AUTHOR]

A numerical approach based on shifted Jacobi-Gauss collocation method for solving mixed Volterra-Fredholm integral equations is introduced. The novel technique with shifted Jacobi-Gauss nodes is applied to reduce the mixed Volterra-Fredholm integral equations to a system of algebraic equations that has an easy solved. The present algorithm is extended to solve the one and two-dimensional mixed Volterra-Fredholm integral equations. Convergence analysis for the present method is discussed and confirmed the exponential convergence of the spectral algorithm. Various numerical examples are approached to demonstrate the powerful and accuracy of the technique. [ABSTRACT FROM AUTHOR]

One of the problems in the numerical analysis of solutions is the nonlinear variable-order fractional convection-diffusion equations for nonsmooth solutions. We offer a numerical technique based on the shifted Legendre Gauss-Lobatto collocation and the shifted Chebyshev Gauss-Radau collocation to solve the problem. The technique with shifted Legendre Gauss-Lobatto and shifted Chebyshev Gauss-Radau nodes is applied to diminish nonlinear variable-order fractional convection-diffusion equations to an easily-solvable system of algebraic equations. Besides, we give numerical test examples to show that the approach can preserve the nonsmooth solution of the underlying problems. [ABSTRACT FROM AUTHOR]

The capacity analysis under mixed traffic flow conditions considers a dynamic problem. Traffic microsimulation models have been a very effective tool for such problem. Calibration and validation of microsimulation models are essential steps to ensure the reliability of the models. This paper suggests the use of measurable variables for calibrating micro-simulation models. Therefore, the objective of this paper is to estimate the roadway capacity through micro-simulation models calibrated using spot speed distributions. The micro-simulation software VISSIM was used to model and analyze the two-lane and multi-lane roads. The models were calibrated and validated using the data collected in Menoufia Governorate, Egypt. The K-S test was performed to ensure that simulated speed distributions matched the observed distributions. It was found that the models were successfully calibrated and validated. Finally, roadway capacity was estimated based on field data and micro-simulation models through the flow rate-density relationship. The results showed a good match between the field and simulated capacity. [ABSTRACT FROM AUTHOR]

The phenomena of buoyant Marangoni natural convection in a right-angled trapezoidal enclosure filled with water-based nanofluids have been studied numerically. The left vertical wall of the trapezoidal cavity is heated uniformly, the right inclined wall is cooled, and the top and bottom walls are insulated (adiabatic). The finite element method (FEM) is implemented to solve the non-dimensional governing equations. The investigation has been done for different values of parameters: the aspect ratio of the enclosure, 0.25 ≤ Ar ≤ 1 , the nanoparticles volume fraction, 0 % ≤ ϕ ≤ 5 % , the Marangoni numbers, 0 ≤ Mabf ≤ 10 3 , and the Rayleigh numbers, 10 3 ≤ Rabf ≤ 10 4. [ABSTRACT FROM AUTHOR]

One of the most attractive subjects in applied sciences is to obtain exact or approximate solutions for different types of linear and nonlinear systems. Systems of ordinary differential equations like systems of second-order boundary value problems (BVPs), Brusselator system and stiff system are significant in science and engineering. One of the most challenge problems in applied science is to construct methods to approximate solutions of such systems of differential equations which pose great challenges for numerical simulations. Bernstein polynomials method with residual correction procedure is used to treat those challenges. The aim of this paper is to present a technique to approximate solutions of such differential equations in optimal way. In it, we introduce a method called residual correction procedure, to correct some previous approximate solutions for such systems. We study the error analysis of our given method. We first introduce a new result to approximate the absolute solution by using the residual correction procedure. Second, we introduce a new result to get appropriate bound for the absolute error. The collocation method is used and the collocation points can be found by applying Chebyshev roots. Both techniques are explained briefly with illustrative examples to demonstrate the applicability, efficiency and accuracy of the techniques. By using a small number of Bernstein polynomials and correction procedure we achieve some significant results. We present some examples to show the efficiency of our method by comparing the solution of such problems obtained by our method with the solution obtained by Runge-Kutta method, continuous genetic algorithm, rational homotopy perturbation method and adomian decomposition method. [ABSTRACT FROM AUTHOR]

A numerical study is made on the entropy generation and magnetohydrodynamics natural convection of Al 2 O 3 -water non-homogeneous nanofluid inside a square enclosure equipped with a heated trapezoidal body. The Galerkin weighted residual finite element method is applied to solve the dimensionless governing equations within the utilized computational domain along with the algorithm of Newton–Raphson iteration that is used for simplifying the nonlinear terms in the equations. The characteristics of fluid flow fields, temperature distributions and entropy generation are studied for an enormous range of the Rayleigh number (10 3 ≤ R a ≤ 10 6) , volume fraction of nanoparticles ( 0 ≤ ϕ ≤ 0.04 ), Hartmann number (0 ≤ H a ≤ 50) , thermal conductivity of the trapezoidal solid body ( k w = 0.5 , 0.76, 1.95, 7 and 16) and the height of the trapezoidal solid body ( 0.15 ≤ D ≤ 0.45 ). It is shown that the streamlines pattern is more sensitive to the increase in the Hartmann number in comparison with the augmentation of the volume fraction of nanoparticles. Also, for a more thermodynamically optimized system, the higher Hartmann number at a higher solid volume fraction of nanofluid is recommended as they show less entropy generation. [ABSTRACT FROM AUTHOR]

Numerous studies have shown the interesting properties of trivalent lanthanide ions when doped in different types of glasses. This article examines the physical, structural and optical properties of series of strontium magnesium borate glasses doped with dysprosium ion (Dy3+) and synthesized using the melt-quenching technique. Physical and optical properties such as density, molar volume, ion concentration, molar refractivity, polaron radius, reflection loss, inter-nuclear distance and molar polarizability for each concentration of the dopant were calculated and reported. The results revealed diverse variations in density with other measured parameters. The amorphous behaviour of the glass samples was confirmed by X-ray diffraction spectroscopy. FTIR spectra measurements revealed the presence of various functional groups and their associated assignments. Optical properties of the activated glass samples with different concentrations of Dy3+ were determined by measuring the absorption and luminescence spectra in the visible region. The UV–Vis–NIR spectrophotometer analysis indicated the presence of eight inhomogeneous transition bands in various positions and intensities with hypersensitive transition at 1260 nm (6H15/2 → 6F11/2). The experimental oscillator strength (fexp) for each calculated absorption band showed higher magnitudes at hypersensitive transition. The optical energy band gap in the current work showed a decrease in values with increasing ion concentrations. The luminescence spectra of the prepared glass phosphors showed three unique transitions at 4F9/2 → 6H15/2 (490 nm), 4F9/2 → 6H13/2 (585 nm) and 4F9/2 → 6H11/2 (689 nm). [ABSTRACT FROM AUTHOR]

This is a brief report on the present status and perspectives of the research programs with negative muon beams. Intense negative muon beams provide new research opportunities for neutrino nuclear responses and nuclear isotope detection and their production. We started the program at the Research Center for Nuclear Physics (RCNP), Osaka University, and now it is continuing at RCNP, J-PARC and the Paul Scherrer Institute (PSI). Gamma rays following ordinary muon capture reactions are used for studies of nuclear responses for anti-neutrinos associated with double beta decays and astro-neutrinos, and for high-sensitivity nuclear-isotope detection and high-efficiency nuclear-isotope production. Recently, we have started a new research project for these subjects in collaboration with Universiti Teknologi Malaysia (UTM) Johor Bahru, RCNP Osaka and the Joint Institute for Nuclear Research (JINR) Dubna. We discuss briefly recent results and perspectives regarding the muon experiments. [ABSTRACT FROM AUTHOR]

In this study, the conjugate natural convection in a square cavity filled with Al 2 O 3 –water nanofluid with an inner conducting solid block is studied numerically using nonhomogeneous Buongiorno's two-phase model. The left wall of the cavity is partially heated and the remaining parts of the wall are adiabatic, while the right wall is fully cooled. The top and bottom horizontal walls are adiabatic. The numerical simulations are based on the finite difference method. The results are simulated for various values of the nanoparticle volume fraction (0 ≤ ϕ ≤ 0.04) , Rayleigh number (10 2 ≤ R a ≤ 10 6) , thermal conductivity of the conjugate square (k w = 0.28 , 0.76 , 1.95 , 7.0) and 16.0 (epoxy: 0.28, brickwork: 0.76, granite: 1.95, solid rock: 7, stainless steel: 16), the size of the inner solid (0 ≤ D ≤ 0.7) , and the length of the heater ( 0.1 ≤ H ≤ 1.0 ). The numerical results for the average and local Nusselt numbers, isotherms, distribution of nanoparticles, and streamlines are presented graphically. The findings indicate that increasing the average solid volume fraction and the size of the solid block as well as the thermal conductivity will enhance the rate of the heat transfer at low values of Rayleigh number R a = 10 3 . On the other hand, increasing these parameters at high values of Rayleigh number ( R a > 10 5 ) decreases the average Nusselt number. [ABSTRACT FROM AUTHOR]

The present study investigates the conjugate heat transfer in a square cavity heated by a triangular solid and saturated with Al2O3-water nanofluid. Two-phase Buongiorno's model is used for modeling the nanofluid heat transfer. The finite element method is used for numerical solution of the dimensionless governing equations subject to the boundary conditions. Comparisons of the proposed method with previously published experimental and numerical works show a good agreement. The effects of some parameters such as the Rayleigh number, thermal conductivity ratio, dimensionless triangular wall thickness and nanofluid volume fraction on heat transfer and nanoparticle distributions are completely studied and discussed. The results show clockwise rotations for streamlines and nanoparticle migration. Also the Nusselt number increases with the nanofluid volume fraction. A continuous reduction is seen for the mean Nusselt number by increasing the dimensionless triangular wall thickness for all the considered values of the Rayleigh number. [ABSTRACT FROM AUTHOR]

This paper investigates a steady mixed convection in a lid-driven square cavity subjected to an inclined magnetic field and heated by corner heater with an inserted square solid block. Water-Al2O3 nanofluid fills the cavity based on Buongiorno's two-phase model. A corner heater is configured in the left lower corner of the cavity by maintaining 40% of the bottom and vertical walls at constant hot temperature. The top horizontal wall is moving and maintained at a constant low temperature. The remainder walls are thermally insulated. The governing equations are solved numerically using the finite element method. The governing parameters are the nanoparticles volume fraction (0≤ϕ≤0.04), Reynolds number (1≤Re≤500), Richardson number (0.01≤Ri≤100), Hartmann number (0≤Ha≤50) and the size of the inner solid (0.1≤D≤0.7). The other parameters: the Prandtl number, Lewis number, Schmidt number, ratio of Brownian to thermophoretic diffusivity and the normalized temperature parameter, are fixed at Pr=4.623, Le=3.5×105, Sc=3.55×104, NBT=1.1 and δ=155, respectively. The inclination of the magnetic field is fixed at γ=π4. Results show that at low Reynolds number, the increase in nanoparticles loading more the 2% becomes useless. It is also found that a big size of the solid block can augment heat transfer in the case of high values of both the Reynolds and Richardson numbers. [ABSTRACT FROM AUTHOR]

Traffic signals at intersections have a significant effect on traffic emissions. They interrupt traffic flow and create additional acceleration and deceleration driving modes. Therefore, the objective of this paper is to perform the optimization process of vehicle delay and exhaust emissions at isolated signalized intersections. Three-leg intersection located in Kafr El-Sheikh City, Egypt was selected in this study. Field delay times were estimated based on vehicle speed and acceleration profiles using GPS device. On-road measurements of vehicle speeds and emissions were collected simultaneously for all movements of all approaches at the selected intersection. The micro-simulation software VISSIM was used to model and analyze the selected intersection. The model was calibrated and validated using the collected data. Signal timing model was developed for the selected intersection and used for optimization of delay time and vehicle emissions. It was found that the changing of signal timing was effective in improving the operational and environmental performance of the traffic signal under study. Also, the results indicated that when the traffic flow rate is higher, the optimal cycle time corresponding to the performance index function increases. Optimization of the delay times and exhaust emissions gives traffic engineers the option of minimizing vehicle emissions in the designing of the signalized intersections or timing a signal system. [ABSTRACT FROM AUTHOR]

Examines the interdiffusion kinetics in Ta/Ni[sub81]Fe[19] polycrystalline multilayer films. Concurrent grain growth and grain-boundary diffusion; Evolution of soft magnetic preperties upon thermal annealing; Background on a kinetic analysis of interdiffusion.

A linear stability analysis has been carried out to examine the effect of internal heat source on the onset of Rayleigh–Bénard convection in a rotating nanofluid layer with double diffusive coefficients, namely, Soret and Dufour, in the presence of feedback control. The system is heated from below and the model used for the nanofluid layer incorporates the effects of thermophoresis and Brownian motion. Three types of bounding systems of the model have been considered which are as follows: both the lower and upper bounding surfaces are free, the lower is rigid and the upper is free, and both of them are rigid. The eigenvalue equations of the perturbed state were obtained from a normal mode analysis and solved using the Galerkin method. It is found that the effect of internal heat source and Soret parameter destabilizes the nanofluid layer system while increasing the Coriolis force, feedback control, and Dufour parameter helps to postpone the onset of convection. Elevating the modified density ratio hastens the instability in the system and there is no significant effect of modified particle density in a nanofluid system. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Plant Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Does racism endure? Should it still exist in an open, liberal multicultural society particularly with the establishment of anti-discriminative laws and societal development? Racism should be minimal among the educated populace in a university where individuals are more likely to be motivated to act in an objective and non-prejudiced manner. Have the programmes and policies that stress on fairness and equality suppressed the manifestation of racism into modern racism? Racial microaggression is an indirect and subtle form of racism that happens in everyday life that may be intentionally and unintentionally executed by the perpetrators and often catch the recipients off-guard. This research aims to unearth the themes of racial microaggression experienced among Malaysian public university scholars. It also explores the reactions of people experiencing racial microaggression. A qualitative study involving personal, one-to-one in-depth interviews was conducted with 40 undergraduates, from 4 racial groups (Malay, Chinese, Indian and East Malaysian) recruited through purposive and snowball sampling. Interpretational Phenomenological Analysis was used to analyse the data. Results indicated 11 common themes such as: (i) Paradox of over-scrutiny/ overlook, (ii) Differential treatment towards people from different race/ religion, and (iii) Assumption of superiority/ inferiority/ intelligence due to race. The reactions include thoughts (e.g. disbelieve) and negative emotions (e.g. disappointment). The results of this research are important in revealing and understanding the phenomenon of racial microaggression. The present research may deliver informative insights into the reality of inter/ intra-ethnic interaction in a university raising awareness and helping to develop effective measurements to reduce such behaviours among scholars. [ABSTRACT FROM AUTHOR]

Presents information on a study which investigated the structural and magnetic properties of epitaxial nickel[sub80] iron[sub20] thin films. Growth of thin films; Experimental procedure; Results and discussion.

Heat absorption and thermal radiation effects in a non-Newtonian fluid on a vertical stretching sheet with suspended particles are considered. The nonlinear partial differential equations are reduced to nonlinear ordinary differential equations via similarity approach. The equations are further solved using shooting- RK4 method and validated with homotopy-Padé solutions. Comparison between previous and present results revealed agreement up to five significant figures. The influence of various parameters on the flow velocity, temperature and concentration are examined. The profiles of reduced skin friction coefficient, Nusselt number and Sherwood number against selected parameters are sketched and discussed. Streamlines of the flow for different Maxwell parameters are visualized too. It is proclaimed that the heat flux of the flow is uplifted as value of either heat absorption or thermal radiation is multiplied. [ABSTRACT FROM AUTHOR]

A study on the pattern of mineral lick use by the Northwest Bornean orangutans ( Pongo pygmaeus pygmaeus) in the Lanjak Entimau Wildlife Sanctuary was carried out from February 2009 to December 2010. A camera trapping method was employed to investigate orangutan mineral lick visitation. The camera traps recorded a total of 263 orangutan visitations or 1.3 % from an overall 22,521 photographs taken. More visits were recorded between August 2009 and March 2010 which coincides with the dipterocarp flowering and fruiting season. Pairs and females with infants were recorded as the most regular visitors compared to pairs and females without infants and solitary males. The visitation time and duration varied among mineral licks and orangutan classes while the interval day visit showed that pairs and females with newborn infants visit the mineral licks continuously from the first day of the study to the tenth day. [ABSTRACT FROM AUTHOR]

This study investigated the effect of an informal values education programme on the development of concept of responsibilities among 5th grade students from ethnic minority groups in Vietnam. For this purpose, 38 students from an experimental group received a values education intervention, while 38 students from a control group did not. The intervention programme was adapted into the Vietnam culture in general and into the Vietnam ethnic minority groups' characteristics in particular. The pre-test and post-test of both groups were evaluated using a questionnaire that measured children's concept of responsibilities designed for the purposes of the study. Findings showed significant differences between the pre-test and post-test for the experimental group on the specified variables but not for the control group. Based on the results, an informal values education programme that has been culturally adapted is therefore suggested to make a positive impact on the development of concept of responsibilities among 5th grade students from the ethnic minority groups in Vietnam. [ABSTRACT FROM AUTHOR]

The buoyant Marangoni convection heat transfer in a differentially heated cavity is numerically studied. The cavity is filled with water-Ag, water-Cu, water-AlO, and water-TiO nanofluids. The governing equations are based on the equations involving the stream function, vorticity, and temperature. The dimensionless forms of the governing equations are solved by the finite difference (FD) scheme consisting of the alternating direction implicit (ADI) method and the tri-diagonal matrix algorithm (TDMA). It is found that the increase in the nanoparticle concentration leads to the decrease in the flow rates in the secondary cells when the convective thermocapillary and the buoyancy force have similar strength. A critical Marangoni number exists, below which increasing the Marangoni number decreases the average Nusselt number, and above which increasing the Marangoni number increases the average Nusselt number. The nanoparticles play a crucial role in the critical Marangoni number. [ABSTRACT FROM AUTHOR]

The mixed convection boundary layer flow of a micropolar nanofluid near a stagnation point along a vertical stretching sheet is investigated. The transformed nonlinear system of ordinary differential equations are solved using the shooting technique with Runge-Kutta Fehlberg method. Comparisons between present and previous results in the absence of nanofluid are tabulated. Several flow velocity, temperature and nanoparticle volume fraction profiles are visualized. The graphical variations of the reduced skin friction coefficient, the reduced Nusselt number and the reduced Sherwood number of both assisting and opposing flows are also presented. The effects of material parameter and microrotation on the Nusselt number are similar with the findings of other researchers. The presence of slip velocity between the base fluid and the nanoparticles has significant impact on the heat transfer enhancement of the stagnation flow of micropolar nanofluid. [ABSTRACT FROM AUTHOR]

In the present study, the slip boundary layer flow of a power-law non-Newtonian fluid over continuously moving permeable surface with internal heat generation/absorption has been examined at prescribed surface temperature taking into account the effect of viscous dissipation. The governing partial differential equations along with the boundary conditions are first cast into a dimensionless form and then the reduced ordinary differential equations are solved numerically via Dormand-Prince pair and shooting method. Comparison of numerical results is made with the earlier published results under limiting cases. The values of the local skin friction coefficient and the local Nusselt number are obtained and presented, graphically. A comprehensive parametric study is carried out to investigate the effects of involved parameters of the problem and it is shown that the rate of heat transfer increases with the surface temperature parameter, Prandtl number, internal heat absorption and suction. [ABSTRACT FROM AUTHOR]

In the present study, the first and second law analyses of power-law non-Newtonian flow over embedded open parallel microchannels within micropatterned permeable continuous moving surface are examined at prescribed surface temperature. A similarity transformation is used to reduce the governing equations to a set of nonlinear ordinary differential equations. The dimensionless entropy generation number is formulated by an integral of the local rate of entropy generation along the width of the surface based on an equal number of microchannels and no-slip gaps interspersed between those microchannels. The velocity, the temperature, the velocity gradient, and the temperature gradient adjacent to the wall are substituted into this equation resulting from the momentum and energy equations obtained numerically by Dormand-Prince pair and shooting method. Finally, the entropy generation numbers, as well as the Bejan number, are evaluated. It is noted that the presence of the shear thinning (pseudoplastic) fluids creates entropy along the surface, with an opposite effect resulting from shear thickening (dilatant) fluids. [ABSTRACT FROM AUTHOR]