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.
Cohesion is well known as the study of the relationships, whether grammatical and/or lexical, between the different elements of a particular text by the use of what are commonly called 'cohesive devices'. These devices bring connectivity and bind a text together. Besides, the nature and the amount of such cohesive devices usually affect the understanding of that text in the sense of making it easier to comprehend. The present study is intendedto examine the use of grammatical cohesive devicesin relation to narrative techniques. The story of Joseph from the Holy Quran has been selected to be examined by using Halliday and Hasan's Model of Cohesion (1976, 1989). The aim of the study is to comparatively examine to what extent the type
... Show MoreThe corcosion behoviour of Aluminum bronze in sodium chloride solution has been studied ^tentiostatically at five temperatures in the range 293-313K.The corrosion potential shifted to more negative values with increasing temperature. The corrosion current density increased with increasing temperature. Values of Tal'el slopes and the transfer coefficients indicated hydrogen evolution reaction to occur at the cathode and mainly the dissolution at the anode.Benzotriazole (BTA) had an inhibiting effect ??? the corrosion of the Al-bronze in deaerated NaCl solution at a concentration (1*10'?- IxlO‘1) mol dm'^ over the temperature range 293-313K. Values of the protection efficiency and kinetics parameters were obtained from the corrosion current
... Show MoreOsteoporosis is described as sickness due to fading bone mass and microarchitecture spoilage of bone tissue leads to consolidation bone fragility and increase risk of fracture. The relationship between osteoporosis and thyroid is important by of the skeleton bones in turnout of circulating physical thyroid hormone and TSH condensation to reduced bone mineral loss in osteoporosis patients, also researcher derives that hormone thyroid and TSH scale increased bone resorption, by increase bone mineral deposition. (110) patients female transfer from provincial and civilian habitation, their ages between (55-75) years old, they pay a visit to DEXA station to measure the density. The samples of blood after diagnosis of disease were taken, then
... Show MoreIn his life, a person engages in different types of verbal and actual dispositions that result in various effects, some of which are necessary and not valid, such as selling, and some are not necessary for one of the two contracting parties, such as a mortgage or both, such as lending and agency. However, there are some actions that are sometimes necessary and not necessary at other times, such as a gift that indicates in its simplest sense. Owning money for another without compensation, it is one of the doors of benevolence and benevolence, and it is one of the attributes of perfection with which God, may He be glorified and exalted be He, described Himself. - And if this analogy is the difference - and distanced himself from greed, the
... Show MoreGenerally, there are many problems that people run into; unemployment is one of these common diseases which usually hits the whole communities leaving crucial effects (economic, social, and psychological) that are difficult to handle them. The current study aims to identify the level of emotional disorders among Iraqi unemployed alumni for the academic years (2013-2016). To this end, the researchers have prepared a questionnaire to measure (anxiety, depression, and anger): these criteria distributed over (30) item. As for sample, it limited to (50) male and female student. The findings of study have revealed that the whole sample showed a high level of emotional disorders, and anger disorder showed higher level than the level of (depress
... Show MoreIn this paper, Mann-Kendall test was used to investigate the existence of possible deterministic and stochastic climatic trends in (Baghdad,Basrah,Mosul,Al-Qaim) stations. The statistical test was applied to annual monthly mean of temperatures for the period (19932009). The values of S-statistic were (62, 44, 52, 64) by comparing these values with the table of null probability values for S we get a probability of (0.002, 0.026, 0.010, 0.002) this result is less than α for the 95% confidence level (α = 0.05) indicating a significant result at this level of confidence. Concluded that an increasing trend in concentration is present at the 95% confidence level and the variance of the S-statistic is calculated and it is com
... Show MoreBackground: Oral health is a mirror of general health. During pregnancy, oral health is affected by changes in saliva and oral hygiene measures which may lead to more dental caries.
Objective: Assess oral health status in relation to salivary antimicrobial peptides in pregnant women.
Subjects and Method: This cross sectional study was carried out in different primary health care centers in Rusafa sectors/ Baghdad city. The total sample included was 80 women (their age range from 21-30). The study group consisted of 40 pregnant women: half of them were in the first trimester and others were in third trimester, while the control group included 40 non-pregnant married fem
... Show MoreThe commercial job is one of the most important businesses in the cities as there is no city can exist without commercial markets to offer service to its inhabitants. This study aims to distribute the commercial function in Abu Tayara Street located in the municipality of Al-Dora by highlighting the size of such businesses in this street. It focuses on analyzing the change that has occurred due to the usages of the commercial land not only in the residential areas, but also in various aspects associated with the growth of the population in the city. Both expansion and development of the economic and social aspects in the area have increased the demand for commercial services. So, the research focuses on the aspects of functional speciali
... Show MoreNowadays, many new technologies developed in a lot of countries. These technologies are promising in many areas such as environmental monitoring, precision agriculture as well as in animal production. The purpose of this study was to define a better understanding of how new and advanced technologies affect the agriculture and livestock sector alike. Although agriculture and animal husbandry are among the most important sectors, advanced equipment and information technology cannot be used adequately. This situation leads to low production efficiency. It is also known that there can be a significant difference in temperature between the position of the climate control sensor (room temperature) and the area occupied by the animal. This study e
... Show MoreThe liver is one of the most prominent glands in the digestive system. It crosses vital organs with multiple functions, including the secretion of enzymes, digestion of fats, and secretion of bile. Through histological studies and those interested in them, the tissue structure of the liver is of interest to researchers, and the four samples of Guinea pig Cavia porcellus were taken in this study to know the histological structure and compare it with rodents in particular. and other animals in general. The results of the liver parenchyma were comparable to those of the studied mammals in periods of hepatocytes, Kupffer cells, and sinusoids surrounding the central vein, blood supply, and bile ducts. He did not record differences, eve
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