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.
DBN Dr. Liqaa Habeb, International Journal of Multidisciplinary Reseach, 2015
Many literary research papers have dealt with the work of Margaret Atwood's The Handmaid's Tale (1985) as a feminist work. However, nearly few studies combine social oppression with religious extremism. To bridge this gap, the present study aims at exploring the use of totalitarian theocracy of terror to oppress its citizens in the name of religion. In other words, it explicates the way religion is used to brutally suppress and exploit people in general and vulnerable women in particular. To meet this objective, the study adopted the qualitative descriptive method to describe how religion is used as a contradictory controlling means in Gilead discourse. It also adopted the Foucault theory in analyzing the data of the study, illu
... Show MoreThe researcher seeks to know the extent of applying the concept of design by Iraqi electronic press sites to provide media product with the acceptance of their browsers and ensure their repeated visits to such sites in the framework of the guiding rules for laser browsing. The researcher uses analytical study on a sample of six Iraqi electronic newspaper sites to identify the general features of their design and the methods of distribution of the structural elements of the pages. The researcher also conducts a field study on a sample of the surfers of electronic newspaper sites to see the extent of their evaluation to their design and the degree of their satisfaction.
A spectrophotometric reliable, rapid and sensitive method has been developed and validated for the determination Ketotifen fumarate . A method was described for the determination of Ketotifen Fumarate in pure form or pharmaceutical formulations, a colored ion-pair complex formation reaction among ketotifen fumarate and acid-dye bromophenol blue at pH 3.0 was used for the colorimetric determination of the drug. The complex formed was extracted into chloroform and the maximum absorbance of the solution was measured at 413 nm against blank. The calibration curve calculated obey Beer's law over the concentration range of 0.4-16 μg/ml and the regression equation was A=0.069
... Show MoreThe theory of general topology view for continuous mappings is general version and is applied for topological graph theory. Separation axioms can be regard as tools for distinguishing objects in information systems. Rough theory is one of map the topology to uncertainty. The aim of this work is to presented graph, continuity, separation properties and rough set to put a new approaches for uncertainty. For the introduce of various levels of approximations, we introduce several levels of continuity and separation axioms on graphs in Gm-closure approximation spaces.
The problematic of the current research marked (style between alienation and westernization in contemporary painting) is demonstrated by the fact that the stylistic forms in art are full of the influx of subjective and emotional impressions, as well as administrative and borrowing techniques, as well as their contextual meaning, whether cultural, social and political, which gives them an alien dimension at one time or another. The aim of the research is: Define the style between alienation and alienwesternization in contemporary painting. The research included six axes dealing with the first axis: an introduction to the concept of alienation, and the second axis dealing with the style in romanticism. The third dealt with: the method in i
... Show MoreThe quality of groundwater should be improved by keeping safe water sources from contaminants in protective way by doing regular measuring and checkup before it supplied for usage. Private Wells do not receive the same services that wells supplying the public do. Well owners are responsible for protecting their drinking water. This work was carried out in Badra city, Iraq from December 2017 to May 2018, six wells water were investigated to determine the general characteristics of wells as well as studying the effect of environmental factors on the quality of water. The average of six wells were eleven parameters that is out of permissible limits were EC, Sal., Alk., TH, TDS, Na, Ca, Cl, SO4, Fe, Zn (4402-5183 /cm, 2.76-3.9 ppt
... Show MoreThis study was undertaken to prepare Nano zinc oxide (ZnO) by precipitation and microemulsion methods. Scanning electron microscopy (SEM), X-ray diffraction (XRD), FTIR spectrometry, atomic force microscopy (AFM), and Brunauer Emmett Teller (BET) surface area were the techniques employed for the preparation. The particle size of prepared nano ZnO was 69.15nm and 88.49nm for precipitation and microemulsion methods, respectively, which corresponded to the BET surface area 20.028 and 16.369m2/g respectively. The activity of prepared nano ZnO as a photocatalyst was estimated by the removal of ampicillin (Amp) under visible light. This study, therefore, examined the effect of pH in the range of 5-11, initial concen
... Show MoreIntroduction and Aim: Kruppel Like Factor 14 (KLF14) gene plays an important role in metabolic illnesses and is also involved in the regulation of many other biological processes. This study's objective was to determine whether or not the KLF14 single-nucleotide-polymorphism (SNP) known as rs972283 was linked to an increased risk of peptic ulcer disease in the population that was being investigated. Materials and Methods: Participants in this study included 71 people who had been diagnosed with peptic ulcers and 50 people who were considered to be healthy controls. In order to genotype the KLF14 SNP rs972283, an amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) was carried out, and the PCR results were
... Show MoreSeven leafhoppers (Cicadeilidae). and one plantboppei (Delpbacidae), Homoptera were identified from a one year operated light trap at the College of Agiculture farm in Abu¬Ghraib. The leafhoppers were: Balclutha hortensis Lind.; B. rufaofasciata Merine.; psammctettix alien us Dahlbem.; P. striatus L.; Extianus capicola.; Neoaliturus haematoceps H. R.; and Orozius albicnctus Dist. The planthopper was Sogatella vibix Haupt. one year records of their populations, indicated that B. rufofasciata occured during the fall from October 10 until December 18; E. capicola from October 24 until November 21 and again in the summer from March to October. The others occured only during the summer, from the end of March and early April until Mid-Septemb
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