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.
Abstract The dissemination of knowledge is no longer confined to schools and universities, not even books. For nearly two centuries, the media have become prominent in disseminating knowledge and culture, in its public and particularly political aspects. After the development of the media from newspapers and magazines to the visual media, their role has increased from the dissemination of abstract information and abstract knowledge towards the process of forming new knowledge through what it publishes and broadcasts from different programs such as drama, news and talk shows. The impact of the media has changed the overall community awareness. Half a century ago the media was not so powerful and widespread. The evolution of the 1990s made
... Show MoreIn this research, the use of natural materials like wool and cannabis as intermediate reinforcement for prosthetic limbs due to their comfort, affordability, and local availability was discussed. As part of this study on below-the-knee (BK) prosthetic sockets, two sets of samples were made using a vacuum method. These sets were made of natural fiber-reinforced polymer composites with lamination 80:20: group (Y) had 4 perlon, 1 wool 4 perlon, and group (G) had 4 perlon, 1 cannabis 4 perlon. The two groups were compared with a socket made of polypropylene. Tensile testing was used to determine the mechanical characteristics of the socket materials. The Y group has a yield stress of 17 MPs, an ultimate strength of 18.75 MPa, and an elastic
... Show MoreFifty patients(24 female and 26 male)with pressure ulcersassociated with different diseasesand attending AL-yarmouk Teaching Hospital in Baghdad were selected in this study. The duration of sample collection was from March to December 2018. All blood samples collected from patients were submitted to a blood culturing technique to examine bacteremia. The results showed that12 blood bacterial isolates were obtained. The isolated bacteria were subjected to Vitek-2, which is an accurate identification technique. The results of the blood culturing technique revealed that 33.3% were Gram negative bacteria, while 66.6% were Gram positive. Diagnosis by Vitek-2 showed that 33.3% wereStaphylococcus spp. , 33.3% were Enterococcus
... Show MoreObjective: To conduct a standardized method for cavity preparation on the palatal surface of rat maxillary molars and to introduce a standardized method for tooth correct alignment within the specimen during the wax embedding procedure to better detect cavity position within the examined slides. Materials and methods: Six male Wistar rats, aged 4-6 weeks, were used. The maxillary molars of three animals were sectioned in the frontal plane to identify the thickness of hard tissue on the palatal surface of the first molar which was (250-300µm). The end-cutting bur (with a cutting head diameter of 0.2mm) was suitable for preparing a dentinal cavity (70-80µm) depth. Cavity preparation was then performed using the same bur on the tooth
... Show MoreThere are numerous ways to define the traits of influential professors, including behavior (such as warmth, civility, and clarity), knowledge (of subject matter and students), and beliefs, among many others. According to research; influential teaching can also defined as the capacity to improve student achievement. This; is only one way to express effectiveness, as stated. However; the preferred definition of high-quality teaching in the United States and many other countries is teacher effects on student achievement. Therefore; this study aimed to determine the characteristics of influential professors in Online Teaching at the English department. This study; believed to be significant for college professors who will show them how
... Show MoreGlassy polymers like Poly Mathyel Metha Acrylate are usually classified as non-porous materials; they are almost considered as fully transparent. Thin samples of these materials reflect color changing followed by porous formation and consequently cracking when exposed to certain level of ?-irradiation. The more the dose is the higher the effect have been observed. The optical microscope and UV-VIS spectroscopy have clearly approved these consequences especially for doped polymers.
Simple, sensitive and accurate two methods were described for the determination of terazosin. The spectrophotometric method (A) is based on measuring the spectral absorption of the ion-pair complex formed between terazosin with eosin Y in the acetate buffer medium pH 3 at 545 nm. Method (B) is based on the quantitative quenching effect of terazosin on the native fluorescence of Eosin Y at the pH 3. The quenching of the fluorescence of Eosin Y was measured at 556 nm after excitation at 345 nm. The two methods obeyed Beer’s law over the concentration ranges of 0.1-8 and 0.05-7 µg/mL for method A and B respectively. Both methods succeeded in the determination of terazosin in its tablets
Leishmaniasis is a transmissible infection brought about by an obligatory intracellular protozoan from the genus Leishmania. It occurs worldwide in tropical and subtropical regions and can be burdensome in resource-constrained countries. The infection ranges in severity from mild cutaneous lesions to more severe and sometimes life-threatening visceral and distorting mucocutaneous sicknesses. Importantly, cutaneous leishmaniasis (CL) is prevalent in the Middle East with a pooled prevalence of 12%. It imposes a significant health and socioeconomic burden
The Sound of the letter (ق) in the Contemporary Arabic Dialects
Rheumatoid arthritis is a worldwide inflammatory chronic autoimmune disease with varying severity. Due to no definitive cure for this disease, current therapies aim to decrease the pain and slow further damage. The interleukin (IL)‐36 cytokine was little known for its role in rheumatoid arthritis; this research aimed to evaluate the serum IL36 levels in RA patients compared to healthy controls. This study included 80 patients with rheumatoid arthritis registered at the Rheumatology Clinic in Baghdad teaching hospital. The patients were divided into three groups based on the treatments received. Group 1 included patients treated with biological therapy (etanercept, adalimumab), Group2 patients with non-biological treatment (methotr
... Show More