In this paper, we use concepts and results from percolation theory to investigate and characterize the effects of multi-channels on the connectivity of Dynamic Spectrum Access networks. In particular, we focus on the scenario where the secondary nodes have plenty of vacant channels to choose from-a phenomenon which we define as channel abundance. To cope with the existence of multi-channels, we use two types of rendezvous protocols: naive ones which do not guarantee a common channel and advanced ones which do. We show that, with more channel abundance, even with the use of either type of rendezvous protocol, it becomes difficult for two nodes to agree on a common channel, thereby potentially remaining invisible to each other. We model this invisibility as a Poisson thinning process and show that invisibility is even more pronounced with channel abundance. Following the disk graph model, we define and characterize connectivity of the secondary network in terms of the available number of channels, deployment densities, number of transceivers per node, and communication range. When primary users are absent, we derive the critical number of channels which maintains super-criticality of the secondary network. When primary users are present, we characterize and analyze the connectivity for all the regions: channel abundance, optimal, and channel deprivation. Our results can be used to decide on the goodness of any channel rendezvous algorithm by computing the expected resultant connectivity.
The study aims to identify the neurological perfectionism of talented girls with disabilities and do a case study for one of these girls. The sample of the study consisted of (11) female students at the university level, 5 females with disability and (6) normal female-students. The sample also included (19) secondary school female students in Tabuk region, including 10 students with visual disability and (9) normal students. The case study was limited to one case of mentally superior girls (talented) with kinetic disability. The researcher adopted the descriptive methodology (case study), he used neurological perfectionism scale, Salah Mekhemar interview, Stanford interfacial intelligence scale fifth picture, case study form. The re
... Show MoreObjective(s): This study was conducted to deal with the importance and effect of various variables which might
have influence in hydrocephaly occurrence.
Methodology: A retrospective design was performed and continued for 4 months. It included 89 nonrandomized
consecutive samples collected from the Early Detection of Childhood Disabilities Center (E.D.C.D.C.)
Duhok. The population involved was the entire cases of both sexes that attended the centre during the period from
1
st.Jan, 1998 to 30th. Dec. 2008 with final diagnosis of hydrocephaly. Patients’ records from the centre were used to
collect data.
Results: Hydrocephaly has been recognized as a public health problem in Duhok province, Iraqi Kurdistan region,<
Abstract Since 2003. Iraq has begun a new phase in its modern history, which was after a long period of tyranny, repression of freedom of expression, and women were no better off than men; they suffered marginalization and exclusion, but after the fall of the former regime and the adoption of a parliamentary system of government, The level of participation in the government; where it approved the share of women in the legislative authority called "quota" which reflects the legislative level of a certain proportion of the seats in Parliament, amounting to 25%, and this is approved by the Iraqi constitution for 2005. But it is noticeable that women in parliament did not work within the quota; in other words they belonged to the pol
... Show MoreOwing to the energy crisis and pollution problems of today, investigations have concentrated on
decreasing fuel consumption and on lowering the concentration of toxic components in combustion
products by using non-petroleum, renewable, sustainable and non-polluting fuels. While conventional energy sources such as natural gas, oil and coal are non-renewable, alcohol can be coupled to renewable and sustainable energy sources.
In this study, the combustion characteristics of diesel fuel and methanol blends were compared.
The tests were performed at steady state conditions in a four-cylinder DI diesel engine at full load at
1500-rpm engine speed. The experimental results showed that diesel methanol blends provided
12.7% inc
The core idea of this study revolves around the news coverage by Iraqi satellite channels regarding corruption issues and their implications on the public's perception of the political process. The researcher designed a content analysis form encompassing both primary and sub-categories of news bulletins from the channels, Dijlah and Al-Itijah, spanning from 01/06/2021 to 31/08/2021, using a comprehensive enumeration method. The chosen timeframe preceded the parliamentary elections held in October 2021. Employing a descriptive-analytical approach coupled with observation, the researcher derived results that met the study's objectives. Among these findings, news items enhanced with video content topped the categorie
... Show MoreObjective: is to determine the level of awareness concerning the reproductive health among adolescent girls in
Baghdad City.
Methodology: A cross sectional study was performed in order to assess the level of awareness regarding reproductive
health among 180 adolescent school girls in the age 12-18 years from five secondary schools in Al-Seder Sector in
Baghdad city, the data was collected by direct interview using constructed questionnaire to obtain socio-demographic
characteristics and level of awareness related to reproductive health. The study started from September 2012 to
January 2013.
Results: the results show that the highest percentage of girls (47.7%) was in age (17-18) year's age, (54.5%) at 4th class
se
Was and military music still in Iraq whatever tributary of Music, where contributed Brphi Iraqi music musicians, authors and composers of musicians skilled and qualified teachers, was, and still have a big role in the growth and prosperity and progress of contemporary Iraqi music through active and vital role and make a lot of musical tenders excellence in various military and civilian walks of life whether it be in the days of war or peace.As it is the military music schools and the main source of the most important in the education of these machines and training. Therefore occupies the military musicians in Iraq prestigious and important, particularly in the Iraqi National Symphony Orchestra started the forefront of the musical instrum
... Show MoreBackground: The rapid evolution of Artificial Intelligence (AI) has significantly influenced Education, demonstrating substantial potential to transform traditional teaching and learning methods. AI reshapes teacher-student interactions and the relationship with knowledge. Objective: To analyze the potential benefits, ethical challenges, and limitations of AI in Education based on recent scientific literature, emphasizing the balance between technology and human interaction. Methods: A documentary research approach with a descriptive focus was employed, following the PRISMA protocol for systematic reviews. The search strategy involved analyzing evidence from 18 scientific articles published within the last six years. Results:AI o
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