Massive multiple-input multiple-output (massive-MIMO) is considered as the key technology to meet the huge demands of data rates in the future wireless communications networks. However, for massive-MIMO systems to realize their maximum potential gain, sufficiently accurate downlink (DL) channel state information (CSI) with low overhead to meet the short coherence time (CT) is required. Therefore, this article aims to overcome the technical challenge of DL CSI estimation in a frequency-division-duplex (FDD) massive-MIMO with short CT considering five different physical correlation models. To this end, the statistical structure of the massive-MIMO channel, which is captured by the physical correlation is exploited to find sufficiently

The research aims to design a narrow-band frequency drive amplifier (1.5GHz -1.6GHz), which is used to boost the transmitter amplifier's input signal or amplify the GPS, GlONASS signals at the L1 band.

The Power Amplifier printed circuit board (PCB) prototype was designed using InGaP HBT homogeneous technology transistor and GaAs Heterojunction Bipolar Transistor (HBT) transistor. Two models have been compared; one of the models gave 16dB gain, and the other gave 23dB when using an input power signal (-15dBm). The PCB consumes 2.4W of power and has a physical dimension of 11 x 4 cm.

      Applying 4K, (Ultra HD) Real-time video streaming via the internet network, with low bitrate and low latency, is the challenge this paper addresses. Compression technology and transfer links are the important elements that influence video quality. So, to deliver video over the internet or another fixed capacity medium, it is essential to compress the video to more controllable bitrates (customarily in the 1-20 Mbps range). In this study, the video quality is examined using the H.265/HEVC compression standard, and the relationship between quality of video and bitrate flow is investigated using various constant rate factors, GOP patterns, quantization parameters, RC-lookahead, and other types of video motion sequences. The ultra

The present study analyzes the effect of couple stress fluid (CSF) with the activity of connected inclined magnetic field (IMF) of a non-uniform channel (NUC) through a porous medium (PM), taking into account the sliding speed effect on channel walls and the effect of nonlinear particle size, applying long wavelength and low Reynolds count estimates. The mathematical expressions of axial velocity, stream function, mechanical effect and increase in pressure have been analytically determined. The effect of the physical parameter is included in the present model in the computational results. The results of this algorithm have been presented in chart form by applying the mathematical program.

 The purpose of this research is to investigate the effects of rotation on heat transfer using
inclination magnetohydrodynamics for a couple-stress fluid in a non-uniform canal. When the
Reynolds number is low and the wavelength is long, math formulas are used to describe the stream
function, as well as the gradient of pressure, temperature, pressure rise and axial velocity per
wavelength, which have been calculated analytically. The many parameters in the current model
are assigned a definite set of values. It has been noticed that both the pressure rise and the pressure
gradient decrease with the rise of the rotation and couple stress, while they increase with an
increase in viscosity and Hartmann nu

In this paper, the effect of both rotation and magnetic field on peristaltic transport of Jeffery fluid through a porous medium in a channel are studied analytically and computed numerically. Mathematical modeling is carried out by utilizing long wavelength and low Reynolds number assumptions. Closed form expressions for the pressure gradient, pressure rise, stream function, velocity and shear stress on the channel walls have been computed numerically. Effects of Hartman number, time mean flow, wave amplitude, porosity and rotation on the pressure gradient, pressure rise, stream function, velocity and shear stress are discussed in detail and shown graphically. The results indicate that the effect of Hartman number, time mean flow, wave a

In this paper, we study the impacts of variable viscosity , heat and mass transfer on magneto hydrodynamic (MHD) peristaltic flow in a asymmetric tapered inclined channel with porous medium . The viscosity is considered as a function of temperature. The slip conditions at the walls were taken into consideration. Small
Reynolds number and the long wavelength approximations were used to simplify the governing equations. A comparison between the two velocities in cases of slip and no-slip was plotted. It was observed that the behavior of the velocity differed in the two applied models for some parameters. Mathematica software was used to estimate the exact solutions of temperature and concentration profiles. The resolution of the equatio

     In this present paper , a special model was built to govern the equations of  two dimensional peristaltic transport to nanofluid  flow of a heat source in a tapered  considered in an asymmetric channel. The equations of dimensionless temperature concentration are analytical solve under assumption slow Reynolds number and long wave length. Furthermore, the results that receive by expressing the maximum pressure rise  communicates increased in case of  non-Newtonian fluid when equated with Newtonian fluid. Finally, MATHEMATICA  11 program has been used to solve such system after obtaining the initial conditions.  Most of the results  of drawing  for many are obtained via above program .

In recent years it has spread the used of e-commerce sites quite dramatically. Thus, these sites have become display huge number of diverse products. It became difficulty for the customer to choose what he/she wants from this product. The recommender systems are used to help customers to finding the desired product of their interests and proved to be an important solution to information overload problem.
This paper, designed a recommendation system based on content, which is usually textual description. Furthermore, the proposed system uses cosine similarity function to find the similarities among the characteristics of various products, and nominate a suitable product closer to customer satisfaction. The experimental result shows tha