Cognitive radio is observed as a new approach, which could be cope with the spectral limitations. This approach is designed to detect whether a particular segment of the radio spectrum is currently in use and to jump into the temporarily unused spectrum rapidly without interfering with the transmissions of other users. CR is the promising radio technology which aims to detect and utilize the temporally unused spectrum bands by sensing its radio environment in order to improve spectrum utilization. To enhance the sensing performance, cooperative spectrum sensing has been proposed. However, when the number of cognitive user tends to be very large, the bandwidth for reporting sensing results to the common receiver will be very huge. In this paper we described interference avoidance in spectrum sensing and then we illustrated the benefits of cooperation in cognitive radio by considering a simple user network and showing improvement in agility , we propose a practical scheme which allows cooperation between cognitive users.
The liver (hepatic) is one of the largest glands or organs of the digestive system in the body of living organisms, including rodents, take the squirrel in this study for example. The study and the collection of sources emerged to be put into the hands of those, especially those interested in histological studies, including junior or professionals and veterinarians, knowledge of the stains used in the research and their final results.
The steady state laminar mixed convection and radiation through inclined rectangular duct with an interior circular tube is investigated numerically for a thermally and hydrodynamicaly fully developed flow. The two heat transfer mechanisms of convection and radiation are treated independently and simultaneously. The governing equations which used are continuity, momentum and energy equations. These equations are normalized and solved using the Vorticity-Stream function and the Body Fitted Coordinates (B.F.C) methods. The finite difference approach with the Line Successive Over-Relaxation (LSOR) method is used to obtain all the computational results. The (B.F.C) method is used to generate the grid of the problem. A computer program (Fortr
... Show More The integration of AI technologies is revolutionizing various aspects of the apparel and textile industry, from design and manufacturing to customer experience and sustainability. Through the use of artificial intelligence algorithms, workers in the apparel and textile industry can take advantage of a wealth of opportunities for innovation, efficiency and creativity.
The research aims to display the enormous potential of artificial intelligence in the clothing and textile industry through published articles related to the title of the research using the Google Scholar search engine. The research contributes to the development of the cultural thought of researchers, designers, merchants and the consumer with the importance of integ
The possibility of using the magnetic field technique in prevention of forming scales in heat exchangers pipes using
hard water in heat transfer processes, also the studying the effective and controllable parameters on the mechanism of
scale formation.
The new designed heat exchanger experimental system was used after carrying out the basic process designs of the
system. This system was used to study the effect of the temperature (40-90 °C) and water flow rate (0.6-1.2 L/min) on
the total hardness with time as a function of precipitation of hardness salts from water and scale formation.
Different magnetic field designs in the heat exchanger experimental system were used to study the effect of magnetic
field design a
. Mesopotamian art is thase mployed all around him into forms for artistic purposes and different con not at ions help him to understand the world around him and customized for their interests
The mural architectural art has distinguished traits that made it promote to the rank of the prominent arts that have been employed by the Mesopotamian human to relate to the world the heroic deeds and exploits of that civilization ,that formed greatest and most splendid wonderful works that still illustrious and outstanding till nowadays .The mural architectural art of pottery and glazed considered one of the most ancient wonders of Mesopotamian creation in Old Iraq .The best quintessence of mural
... Show MoreFirstly, in this study, a brief updated description and applications of different solar collectors used in renewable energy systems for supplying electric and thermal energy was presented. Secondly, an attempt was made to utilize tilting orientation of solar collector for maximizing collector energy with time in respect to horizontal orientation. For energy calculation, global solar radiation was used since they are directly related. For that purpose, field measurements of half-hourly radiation on two flat panels of tilting and horizontal orientations were carried out throughout 8-month period under local climate of Baghdad. Then, energy gain and radiation level averages were calculated based on the field radiation
... Show MoreA new laboratory study conducted on stepped spillways in order to investigate their efficiency of dissipating flow energy. All previous study on stepped spillway indicated that the flow energy dissipation decreased as increasing in discharge. Increasing in the step numbers and the spillway slope led to energy dissipation decrease. In this study, an experimental attempt to increase energy dissipation at variable discharges was performed on stepped spillway and that leads to decreasing the cost of initiating the stilling basin or may be ignoring it. Five spillways were constructed from concrete and tested to investigate and compare among them. Three were roughed by gravel with different size for each one, one of them was s
... Show MoreThe aim of this study is to determine serum IL-33 levels and atherogenic index of plasma (AIP) .Forty patients with moderate activity of rheumatoid arthritis (RA) and forty healthy individuals as control group were enrolled in this study, age (25-45) years. Disease activity was assessed in patients by erythrocyte sedimentation rate (ESR),C-reactive protein (CRP) and rheumatoid factor(RF) .Also lipid profile(cholesterol TC, triglyceride TG, low density lipoprotein LDL-C, very low density lipoprotein VLDL and high density lipoprotein HDL-C), AIP, and IL-33 were determined in all subjects. The results revealed a significant increase in ESR,CRP and RF , TG, VLDL,AIP and IL-33,while is a significant decrease in HDL concentration in patients gr
... Show MoreColor is one of the most important elements involved and contributing mainly to designs and visual works, whether they are fixed or mobile, for internal spaces through what color gives it the possibilities on the physical and intellectual level, if the process is linked to the functional performance or the aesthetic value, which is thus included within the system of processors and basic works in Designing the interior spaces and highlighting the functional and aesthetic aspects of them through the executed designs that are linked to certain techniques and mechanisms. Therefore, they are processed according to the references and pressure structures or the creation and modern dealing with materials and designs to implement operations in hi
... Show MoreThe debate on the methodology of media and communication research is no longer subject to the logic of the contradiction between the quantitative and the qualitative approach, nor the logic of the comparison between them. The nature of the topics presented for research, the problems they raise, the goals to be achieved from the research, and the epistemological positioning of researchers are among the critical factors that dictate the appropriate approach or methodological approaches to conduct their research. This positioning means the implicit philosophical principles upon which any researcher relies and which determine the path he/ she takes to produce scientifically approved knowledge. The method of the researcher's access to the phe
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