Channel estimation and synchronization are considered the most challenging issues in Orthogonal Frequency Division Multiplexing (OFDM) system. OFDM is highly affected by synchronization errors that cause reduction in subcarriers orthogonality, leading to significant performance degradation. The synchronization errors cause two issues: Symbol Time Offset (STO), which produces inter symbol interference (ISI) and Carrier Frequency Offset (CFO), which results in inter carrier interference (ICI). The aim of the research is to simulate Comb type pilot based channel estimation for OFDM system showing the effect of pilot numbers on the channel estimation performance and propose a modified estimation method for STO with less numb

The UN organization is considered one of the most important organizations at the international level. It has accomplished multiple tasks and roles of many different issues and events that hit the developing and advanced world countries. It has performed a series of procedures and laws that have had an impact on ending the wars and conflicts that plagued some countries and continued for a period of time in the past. Moreover, it has improved the level of the international relations between a number of countries due to the problems and incidents took place between them. It has relied on finding solutions and treatments for humanitarian problems such as the preservation of the environment, preventing the spread of epidemics and diseases Thi

The two dimensional steady, combined forced and natural convection in vertical channel is
investigated for laminar regime. To simulate the Trombe wall channel geometry properly, horizontal
inlet and exit segments have been added to the vertical channel. The vertical walls of the channel are
maintained at constant but different temperature while horizontal walls are insulated. A finite
difference method using up-wind differencing for the nonlinear convective terms, and central
differencing for the second order derivatives, is employed to solve the governing differential
equations for the mass, momentum, and energy balances. The solution is obtained for stream
function, vorticity and temperature as dependent variables

The Gender study is consider one of the concepts which the Postmodernism reached
after the end of Modernism, where the first one has limited the criticism study choices before
the second after closed many doors of subjects which was enriched by researches.
It is pretty clear that the root of this concept belongs to the Linguistics which provided
the Criticism with a countable reasons of it is growth.
The attention in the study of gender in Feminine Literature and Criticism increased in
Arabic studies since the early years of twenty one century, so this research is presented to be
an introduction to this subject which could pave the way to more studies.
In addition to the Gender studies this research deals with ano

The )Resalat Al-Gofran) which means to Abi Ala Al-Ma'arri is included in the studies of prose in Arabic literature. The study of the "Message of Forgiveness" was passed in two stages. The first is the traditional linguistic study, specifically the rhetorical one. The second study, which took place in the sixties of the last century, was conducted in the light of comparative literary studies, after Dr. Taha Hussein summarized this letter and rid it of its complex language and after Dr. Bent Shati achieved it. Dr. Lewis Awad relied on her study in the light of comparative studies, Which appeared in Europe in the modern era and was able to discover similarities between them and the old texts that dealt with the subject of "literature of the

The Subject  of  contritutions  to Jerusalemites  Scientific  in  Egypt  from  8.5  Century  14.11 AD of  noteworthy  studies  Concern  Coming  Of these  Scientists  to  Egypt  has  helped  toth  to  Seek  Knowledge  and  Study  or  teaching  in  the tooming  w0rid of Science  broadly  and  distinctive  through  Scientific  interaction  and  intermingling  of  Civilization  between  Scientists  this  Mixing  effect  of  the  Scientific  life  and  in tellectal  of The  nam

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    In this paper, we study the peristaltic transport of incompressible Bingham plastic fluid in a curved channel. The formulation of the problem is presented through, the regular perturbation technique for small values of  is used to find the final expression of stream function. The numerical solution of pressure rise per wave length is obtained through numerical integration because its analytical solution is impossible. Also the trapping phenomenon is analyzed. The effect of the variation of the physical parameters of the problem are discussed and illustrated graphically.

Genus Salix is among family Salicaceae, distributing in the northern hemisphere. It is represented in Egypt by two species (Salix mucronata and Salix tetrasperma). The classification of Salix at the generic and infra-generic levels is still outstanding. We have agreed to list the Egyptian species of this genus. We collected them during field trips to most Egyptian habitats; fresh and herbarium specimens were subjected to taxonomic revision based on morphological characters; scanning electron microscope (SEM) for pollen grains; isozyme analysis using esterase and peroxidase enzymes and genetic diversity using random amplified polymorphic DNA (RAPD). We recorded that both sexes of S.