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Connectivity and rendezvous in distributed DSA networks
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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.

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Publication Date
Thu Apr 27 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Study The Properties of Structural And Optical of Cadmium Oxide Films Prepared In A Thermal Evaporation In A Vacuum
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  In   this  research  ,  the  structural   and  optical   properties   of  pure of cadmium  oxide, pure (CdO) were studided thin films in a thermal evaporation in a vacuum depositing metal cadmium pure rules of the glass at room temperature (300K) and thickness (300 ± 20nm) and the time of deposition (1.25sec) was oxidation of thin films cadmium (Cd) record temperature (673k) for a period of one hour to the presence of air optical energy gap for direct electronic transitions were calculated (permitted) as a function of absorption coefficient and permeability and reversibility by recording the spectrum absorbance and permeability of the membrane the record

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Publication Date
Fri Mar 31 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Therapeutic Use of Silymarin in the Management of Suspected Renal and Hepatic Injury Produced by NSAIDs in Osteoarthritis Patients
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Long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) mostly associated with renal and hepatic adverse effects, and the adjunct use of compounds with potent protective effects, like silymarin, may be one of the choices to avoid these effects. This project was designed to evaluate the protective effect of silymarin against the suspected renal and hepatic injury induced with long term use of NSAIDs; 220 patients with osteoarthritis were randomized into 5 groups and treated with either silymarin 300mg/day alone, piroxicam 20mg/day alone, meloxicam 15mg/day alone or the combination of each of them with silymarin for 8 weeks. The renal and hepatic functions were evaluated before starting treatment and after 8 weeks including assessm

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Publication Date
Wed Apr 01 2015
Journal Name
Journal Of Educational And Psychological Researches
The reality of the colleges of education in quality assurance for professors teaching methods in educational and psychological science
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     That achieve a level of excellence for the quality of university education cannot be achieved only by uniting the efforts of all employees at the university and active participation by students and by alumni and the labor market and society, however we can say that the administrative and academic  university staff play an active role and the largest in achieving equivalent quality of higher education, It should unite the efforts of all employees in the educational institution in order to achieve quality education. It is the concept of quality of education, quality assurance and overall management of the quality of the basic pillars on which it is based university education. That highlight the need fo

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Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
Study the effectiveness of crude aqueous extract of the chamomile plant in uterine contractions and miscarriage in mice eggs
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Publication Date
Thu Mar 30 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
In Vitro Effect of Cholesterol and Different Sugars on Digitonin Production in Multiplied Shoots of Digitalis purpurea L. Plant
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Production of  the steroidal saponin digitonin  in multiplied shoots of Digitalis purpurea , (var. Excelsior Mixed) has been achieved in vitro by two experiments. In the experiment 1, shoot tips ( 1cm length ) explants  from the sterilized seedlings were excised and cultured on MS medium ( Murashige and Skoog medium) supplemented with 0.5 mg/L TDZ (thidiazuron) and   cholesterol at the concentrations 0.0, 0.1, 0.3, 0.5, 1.0, 1.5, 2.0 or 4.0 mg/L. After 45 day, results showed that the treatment with 0.5 mg/L TDZ and 2.0mg/L cholesterol had a positive effected on increasing the dry weight of multiplied shoots and their production of digitonin when compared with other treatments, where this treatment gave 2

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Crossref
Publication Date
Wed May 10 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Genetic and Bacteriological Study of Aerobic Bacteria Which Causes Cesarean Section Contamination in Women in The City of Diwaniya
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    This study was designed  to stand  on the most important causes of contamination in sesarean section in women by the aerobic bacteria species the bacteria isolates  were diagnosed in the Maternity and Children  Hospital in the Qadsiya province and in the special clinics. Sixty five persent of women having cesarean operation were contaminated with different bacteria in different ratios. Staphylococcus aureus  showed the higher percentage  (62.4) , Pseudomonas.aerogenosa  18% , E.coli 9.5% and Proteus.spp (6,4%).While Streptococcus pyogens showed lowest percentage 3.6% .  The results of antibiotic sensitivity test for all bacteria  isolates showed  Chloramphenicol and Ami

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Publication Date
Mon Feb 28 2022
Journal Name
Journal Of Educational And Psychological Researches
The Social Dimension of the Phenomenon of Suicide in Iraq: Reasons and Proposals "Field Study in Baghdad Police Stations
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There have been many negative phenomena in Iraqi society, especially after the political crises over the last years, such as the spread of violence, the deterioration of the economic situation, the spread of unemployment and poverty, and the disintegration of social ties, divorce, and the entry of the scourge of drugs. Among the most dangerous of these emergent phenomena, the phenomenon of suicide among young people of both sex, which has grown and increased in an unprecedented manner, surpassing all known social norms in Iraqi society and the prevailing religious values. Suicide in Iraqi society has transformed from a simple case to a visible presence in all Iraqi provinces. Suicides cases have registered in all cities of Iraq and of bo

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Publication Date
Wed Jan 30 2013
Journal Name
Al-kindy College Medical Journal
Regeneration of Pain, Touch, Cold, and Warmth, sensations in split thickness human skin grafts in adults (A clinical study)
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Back ground: Skin grafting is the most common form
of reconstructive surgery, and regeneration of
sensations in skin grafts is a complex process
influenced by many factors such as , the thickness of
the graft, the depth of the grafted bed, meshing of the
graft, the condition of the bed and the surrounding
area. So many studies performed on this subject, some
of them clinically based on subjective type of sensation
tests, and others histological to detect the presence of
nerve fibers in the grafted skin
Objectives: To detect return of sensations to split
thickness skin grafts by clinical methods.
Methods: From Oct. 1995 to Oct. 2010, a clinical
prospective study performed in Al wasity Hospital for

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Publication Date
Tue Jun 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
The Specificity of Government Expenditure Decisions and their Reflection in Financial Performance / Case Study in Diyala Governorate Sewerage Directorate
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The research examines the extent to which government spending decisions can affect the level of the financial performance of the directorate. The research problem was based on the financial reality of the Directorate of Sewerage of Diyala province. Spending on the Directorate of the research area. To achieve a set of objectives: indicate the impact of government spending decisions on financial performance, the use of financial analysis to assess the performance of the Directorate. The research adopted financial analysis tools, a set of financial ratios, through which the spending decisions taken by the Directorate of the field of research will be evaluated, and during the period (2014-2018). The research also adopted statistical

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Crossref
Publication Date
Sat Dec 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
"Testing Caldor's Hypothesis to Estimate the Relationship between the Industrial Production and Growth in Gross Domestic Product in Iraq"
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The study aimed to test the hypothesis of Caldor to estimate the relationship between industrial production and GDP growth in Iraq using with Integration Framework  and to determine the causal relationship in the short and long term using the error correction vector model for the period 1990-2016. the results showed a long-term equilibrium relationship between GDP and industrial output, while Ganger causality tests showed a causal relationship in the long run of GDP to output Subliminal thus illustrated the extent of the recession suffered by the industrial sector, which is supposed to be the driving force of the economy and the development and expansion of the productive base of the industry, so this study recommends attent

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