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An analysis of entropy generation in motion of peristaltic nanofluid through a symmetric channel with Ohmic heating and Hall effects is made here. In this study, the effects of distinct parameters (nanoparticles volume fraction, Hartman number, Hall parameter, etc) on temperature, entropy generation, Bejan number, velocity and heat transfer rate are analyzed. Mathematical modeling is executed by the implementation of low Reynolds number and long-wavelength assumptions. Final nonlinear system has been solved using homotopy perturbation method. Physical analysis has been carried out through graphs. For comparison, numeric and analytic solutions are presented. Moreover, comparisons of numeric and analytic results of heat transportation rate are provided in tabular form. Results indicate that temperature is boosted by the enhancement of Hartman number. Further, entropy generation number shows increasing behavior for rise in the value of heat absorption/generation parameter.

Magnetohydrodynamic (MHD) mixed convection flow of an incompressible Jeffrey fluid induced by a bidirectional stretching surface was investigated. Heat and mass transfer analysis was carried out in the presence of thermophoresis particle deposition and thermal radiation. Convective heat and mass conditions at the boundaries were taken. Mathematical analysis is presented subject to boundary layer assumptions. Homotopic procedure was implemented for the computations of solutions. Impacts of various physical parameters on the dimensionless temperature and concentration fields are plotted and discussed. Physical quantities of interest, namely, the local Nusselt and Sherwood numbers are analyzed through numerical values.

The impact of Cattaneo-Christov heat flux in three-dimensional flow of an Oldroyd-B fluid over a bidirectional stretching surface is explored in this article. The boundary layer flow of an incompressible fluid is considered. Heat transfer analysis is discussed via the Cattaneo-Christov model of heat flux. Similarity transformations lead to the nonlinear ordinary differential systems. Convergent solutions of dimensionless velocities and temperature have been computed. Convergence analysis is presented graphically and numerically. The influence of physical parameters on the velocities and temperature are plotted and discussed. We observed that the values of temperature gradient are higher for the Cattaneo-Christov heat flux model when we compare it with the values obtained by the simple Fourier’s law of heat conduction.

Today, satellite communication networks are being integrated into the infrastructure of modern Terrestrial communication networks and becoming popular for the delivery of educational content and data, as well as education-centric services, including information, tele-conferencing, entertainment, or ‘edutainment’ services. With fresh demand for new services and applications, it is becoming essential that wireless network architecture seamlessly interoperate with new and existing technologies, protocols and standards. This paper presents recent work on the use of hybrid wireless network infrastructures for delivering tele-education and e-learning applications to remote communities by combining a variety of satellite, terrestrial and wireless technologies, and provides the results from live scenarios carried out employing various methods of interoperability testing. The analysis of the results examines a number of different issues such as delay, jitter, packet loss, latency, throughput measurement, and bandwidth. By combining satellite and terrestrial (wireless) technologies, full coverage and high capacity can be achieved for true broadband services for delivering educational content. The interoperability among such diverse networks imposes a number of challenges regarding service provision and management.

In this article, the peristaltic flow of an Eyring-Powell fluid in a curved channel is modeled. Anapproach utilizing along wavelength and low Reynolds number is employed for the analysis in a wave frame. A series solution is obtained. Results for stream function, longitudinal velocity, pressure gradient, and pressure rise are plotted and analyzed. The pressure rise per wavelength is examined numerically. It is noted that results for aplane channel and viscous fluid can be deduced as the limiting cases of the present work. A comparison of flow between the planarand curved channel is also shown.

Peristaltic transport of copper-water nanofluid in an inclined channel is reported in the presence of mixed convection. Both velocity and thermal slip conditions are considered. Mathematical modelling has been carried out using the long wavelength and low Reynolds number approximations. Resulting coupled system of equations is solved numerically. Quantities of interest are analyzed through graphs. Numerical values of heat transfer rate at the wall for different parameters are obtained and examined. Results showed that addition of copper nanoparticles reduces the pressure gradient, axial velocity at the center of channel, trapping and temperature. Velocity slip parameter has a decreasing effect on the velocity near the center of channel. Temperature of nanofluid increases with increase in the Grashoff number and channel inclination angle. It is further concluded that the heat transfer rate at the wall increases considerably in the presence of copper nanoparticles.

The wide occurrence of peristaltic pumping should not be surprising at all since it results physiologically from neuro-muscular properties of any tubular smooth muscle. Of special concern here is to predict the rheological effects on the peristaltic motion in a curved channel. Attention is focused to develop and simulate a nonlinear mathematical model for Carreau-Yasuda fluid. The progressive wave front of peristaltic flow is taken sinusoidal (expansion/contraction type). The governing problem is challenge since it has nonlinear differential equation and nonlinear boundary conditions even in the long wavelength and low Reynolds number regime. Numerical solutions for various flow quantities of interest are presented. Comparison for different flow situations is also made. Results of physical quantities are interpreted with particular emphasis to rheological characteristics.

Today, satellite communication networks are being integrated into the infrastructure of modern Terrestrial communication networks and becoming popular for the delivery of educational content and data, as well as education-centric services, including information, tele-conferencing, entertainment, or “edutainment” services. With fresh demand for new services and applications, it is becoming essential that wireless network architecture seamlessly interoperate with new and existing technologies, protocols and standards. This paper presents recent work on the use of hybrid wireless network infrastructures for delivering tele-education and e-learning applications to remote communities by combining a variety of satellite, terrestrial and wireless technologies, and provides the results from live scenarios carried out employing various methods of interoperability testing. The analysis of the results examines a number of different issues such as delay, jitter, packet loss, latency, throughput measurement, and bandwidth. By combining satellite and terrestrial (wireless) technologies, full coverage and high capacity can be achieved for true broadband services for delivering educational content. The interoperability among such diverse networks imposes a number of challenges regarding service provision and management.

Present study examines the mixed convective peristaltic transport of Cu–H2O nanofluid with velocity slip and convective boundary conditions. Analysis is performed using the two-phase model of the nanofluid. Viscous dissipation and heat generation/absorption effects are also taken into account. Problem is formulated using the long wavelength and low Reynolds number approach. Numerical solutions for the pressure rise per wavelength, pressure gradient, axial velocity, temperature and heat transfer rate at the boundary are obtained and studied through graphs. Results show that the area of peristaltic pumping decreases with an increase in the nanoparticles volume fraction. Increase in the velocity slip parameter shows an increase of the pressure gradient in the occluded part of the channel. Further, addition of copper nanoparticles reduces both the axial velocity and temperature of the base fluid. Temperature of the nanofluid also decreases sufficiently for an increase in the value of Biot number.

We investigate the Cattaneo–Christov heat flux model for a two-dimensional laminar boundary layer flow of an incompressible Oldroyd-B fluid over a linearly stretching sheet. Mathematical formulation of the boundary layer problems is given. The nonlinear partial differential equations are converted into the ordinary differential equations using similarity transformations. The dimensionless velocity and temperature profiles are obtained through optimal homotopy analysis method (OHAM). The influences of the physical parameters on the velocity and the temperature are pointed out. The results show that the temperature and the thermal boundary layer thickness are smaller in the Cattaneo–Christov heat flux model than those in the Fourier's law of heat conduction.

By combining satellite and terrestrial (wireless) technologies, full coverage and high capacity can be achieved for true broadband services. The interoperability of such diverse networks imposes a number of challenges regarding service provision and management. The end-to-end quality of service (QoS) management implies that features such as service scalability between different networks have to be available. On the other hand, wireless QoS capabilities provide a promising diversity for a wide range of seamless applications. However, differences in QoS properties between both the wired and the wireless applications have a considerable effect on the quality level as well as platform and application dimensions of network interoperability. This paper examines the so-called interoperability requirements in integrated uses of satellite communication technology together with terrestrial (wireless) network technology for seamless delivery of broadband services (using ISABEL and CLIX e-learning applications) in rural and remote areas. This is demonstrated with an example of two educational, real-time and recorded, eLearning services.

Due to rapid and constant evolution of wireless communication technologies, standards, protocols, applications, and systems, it is hard to rely on personal experience to make their selection, design and deployment. Testing helps to determine actual performance and limitations of technologies. Testing is also important to avoid the financial and reputation losses of the company as well as to ensure uninterrupted flow of the information for essential services such as healthcare, airports, railways, and military services. Testing covers many aspects of a communications network, including interoperability, conformance, performance and availability. The end-to-end quality of service management implies that features such as service scalability between different networks have to be available. However, wireless QoS requirements are very diverse due to its seamless applications, and moreover, , differences in QoS properties between both wired and wireless applications have a considerable effect on the level of user service quality as well as platform and application dimensions of network interoperability. The aim of this paper is to establish the network performance and availability requirements for the integrated use of satellite communication technology together with terrestrial network technology in a particular, niche application area, namely the seamless delivery of educational services in rural and remote areas. The suggested testing programme aims to identify the performance and availability issues for the operation of heterogeneous satellite-terrestrial network technologies.

This paper addresses the effects of applied magnetic field and partial slip effects in peristalsis of water-based nanofluids in an asymmetric flow configuration. Analysis is carried out using silver and copper nanoparticles. Viscous dissipation, mixed convection, Ohmic heating and heat generation/absorption are considered. Mathematical modeling is done employing lubrication approximations. Resulting coupled system is solved numerically. Physical quantities like axial velocity, pressure gradient, temperature and heat transfer rate are graphically analyzed. Comparison between the silver–water and copper–water nanofluids is presented and analyzed. Results show that the maximum velocity, temperature and heat transfer rate at the wall in silver–water nanofluid are comparatively greater than that of copper–water nanofluid. It is also observed that addition of nanoparticles results in a decrease in the velocity and temperature of fluid. However, the heat transfer rate at the wall is enhanced through addition of nanoparticles.

Advancements in the biomedical engineering have enhanced the usage of magnto-nanoparticles in improving the precision and efficiency of the magneto-drug delivery systems. Such systems make use of the externally applied magnetic fields to direct the drug towards a specific target in the human body. Peristalsis of magneto-nanofluids is of significant importance in such considerations. Hence peristaltic transport of Fe3O4-water nanofluid through a two-dimensional symmetric channel is analyzed in the presence of an externally applied constant magnetic field. Hamilton-Crosser’s model of the thermal conductivity is utilized in the problem development. The nanofluid saturates a non-uniform porous medium in which the porosity of the porous medium varies with the distance from the channel walls. Analysis is performed for the spherical and the cylindrical nanoparticles. Resulting system of equations is numerically solved. Impacts of sundry parameters on the axial velocity, temperature, pressure gradient and heat transfer rate at the boundary are examined. Comparison between the results for spherical and cylindrical nanoparticles is also presented. Results show that the nanoparticles volume fraction and the Hartman number have increasing effect on the pressure gradient throughout the peristaltic tract. Effective heat transfer rate at the boundary tends to enhance with an increase in the nanoparticles volume fraction. Use of spherical nanoparticles results in a higher value of axial velocity and the temperature at the center of channel when compared with the case of cylindrical nanoparticles.

This article explores the hydromagnetic steady flow of Jeffrey fluid in the presence of thermal radiation. The chosen nanofluid model takes into account the Brownian motion and thermophoresis effects. Flow and heat transfer characteristics are determined by a stretching surface with flux conditions. The nonlinear boundary layer flow through partial differential systems is converted into the ordinary differential systems. The resulting reduced systems are computed for the convergent solutions of velocity, temperature and nanoparticle concentration. Graphs of dimensionless temperature and nanoparticle concentration profiles are presented for different values of emerging parameters. Skin-friction coefficient are computed and analyzed in both hydrodynamic and hydromagnetic flow situations.