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Multi-Channel Distributed DSA Networks: Connectivity and Rendezvous Tradeoffs
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In this paper, we investigate and characterize the effects of multi-channel and rendezvous protocols on the connectivity of dynamic spectrum access networks using percolation theory. 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-channel, 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 protocols, 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 represent the multiple channels as parallel edges in a graph and build a multi-layered graph (MLG) in R2. In order to study the connectivity, we show how percolation occurs in the MLG by coupling it with a typical discrete percolation. Using a Boolean model and the MLG, we study both cases of primaries' absence and presence. For both cases, we define and characterize connectivity of the secondary network in terms of the available number of channels, deployment densities, number of simultaneous transmissions per node, and communication range. When primary users are absent, we derive the critical number of channels which maintains supercriticality 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. For each region we show the requirement and the outcome of using either type of rendezvous techniques. Moreover, we find the tradeoff between deployment-density versus rendezvous probability which results in a connected network. Our results can be used to decide on the goodness of any channel rendezvous algorithm by computing the expected resultant connectivity. They also provide a guideline for achieving connectivity using minimal resources.

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Publication Date
Tue Mar 31 2020
Journal Name
College Of Islamic Sciences
Ruling on abortion in Sharia and law
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Research title: Ruling on abortion in Sharia and law.

The importance of research: Projection is of great importance because it touches the life of a living being who enjoys human qualities. However, this organism often wastes its rights and does not protect its human beings. These souls are lost in millions by the sake of casual desire or hidden desire.

The research plan: The research dealt with an introductory topic, four topics, and in each topic there are demands, branches, and a conclusion.

The most important findings of the study: The ruling on aborting the fetus in the Sharia is only permissible (and the necessity is valued at its va

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Publication Date
Fri Jun 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Banking efficiency between concept and measurement methods
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The research aims to review the concepts of banking efficiency and its relationship to performance, productivity and efficiency, as well as analyze the efficiency of the banking in micro-economic view.
In order to achieve the objectives of the research We have been employed graphic, Econometrics  and Mathematical methods to derive the different concepts of banking efficiency.

We showed that there are two main methods used to measure the bank efficiency, the first called Stochastic Frontier Analysis , this technique depends on the parametric methods, The other method is called Data Envelopment Analysis is based on mathematical programming methods

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Publication Date
Thu Sep 08 2022
Journal Name
Al-khwarizmi Engineering Journal
Design and Analysis of a Spraying Robot
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An indoor spraying robot is built in this research to solve numerous challenges associated with manual spraying. The mechanical, hardware and essential technologies used are all detailed and designed. The proposed spraying robot's conceptual design is split into two parts: hardware and software. The mechanical design, manufacturing, electrical, and electronics systems are described in the hardware part, while the control of the robot is described in the software section. This robot's kinematic and dynamic models were developed using three links that move in the x, y, and z directions. The robot was then designed using SolidWorks software to compute each connection's deflection and maximum stresses. The characteristics of the stepper moto

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Publication Date
Wed Mar 16 2022
Journal Name
Journal Of Educational And Psychological Researches
Internet Addiction: Healthy, Psychological, and Social Implications
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The aim of the current research is to explore the health, psychological, and social implications of Internet addiction. Internet addiction is a new type of addiction, which negatively affects an individual’s life and creates social problems, psychological and nervous disorders. The research is divided into three sections: The first section is devoted to the definition of the research and includes the research problem, its importance in addition to the objectives, and the search terms were defined in it. The second section included the concept of addiction on the Internet and the causes, symptoms of addiction, forms, and previous studies were reviewed. As for the third topic, it deals with the theories explaining Internet addiction and

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Publication Date
Sat Apr 30 2022
Journal Name
Iraqi Journal Of Science
On Large-Lifting and Large-Supplemented Modules
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      In this paper, we introduce the concepts of Large-lifting and Large-supplemented modules as a generalization of lifting and supplemented modules.  We also give some results and properties of this new kind of modules.

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Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
Antimutagenicity of arugula(Eruca sativa) and carrot
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Been studying the opposite effect of mutagenesis to juice plant watercress and compared juice carrots to induce mutations resistant Struptomaysan Palmtafr (NTG) and transactions as diverse as the use of juice before treatment Palmtafr or after using Almtafr or with Almtafr using system mutagenesis Bactra consisting of three isolates G3, G12, G27 are very sensitive to Struptomaysanstudy resulted in a user juice plants had no effect on the neighborhood number of isolates, but its effect on the watercress was clear

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Publication Date
Tue Dec 07 2021
Journal Name
2021 14th International Conference On Developments In Esystems Engineering (dese)
Object Detection and Distance Measurement Using AI
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Publication Date
Wed Dec 13 2017
Journal Name
Al-khwarizmi Engineering Journal
Synthesis and Characterization of Nanocrystalline Zeolite Y
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Worldwide attention is being focused on  nanocrystalline  zeolites  and they are replacing conventional ones due to their pronounced potential in many fields. In this study, NaY zeolite has been prepared hydrothermally using sol –gel method and modified to the proton type by ion –exchange process. Characterization is made using X-ray diffraction (XRD), thermogravimetric analysis (TGA),  Fourier transform infrared spectroscopy (FTIR),  Atomic force microscopy (AFM), Brunauer –Emmet- Teller (BET) nitrogen adsorption method, Ammonia Temperature programmed desorption (NH3-TPD) and Scanning electron microscopy( SEM).  The effect of aging time, silica to alumina ratio is studied and the results sh

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Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
fabrication and study the characteristic of PbTelSi
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In this research has been the manufacture and study the properties of the solar cell type retail hybrid manner thermal evaporation emptiness were studying the properties of the cell at room temperature showed measurements stream circuit behavior linear cell manufacturers reached were calculated efficiency tool cell manufacturers, as well as the expense of workers filling the cell

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Publication Date
Sat Aug 01 2020
Journal Name
Journal Of Engineering
Urban Morphological Studies (Concepts, Techniques, and Methods)
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Urban morphological approach (concepts and practices) plays a significant role in forming our cities not only in terms of theoretical perspective but also in how to practice and experience the urban form structures over time. Urban morphology has been focused on studying the processes of formation and transformation of urban form based on its historical development. The main purpose of this study is to explore and describe the existing literature of this approach and thus aiming to summarize the most important studies that put into understanding the city form. In this regard, there were three schools of urban morphological studies, namely: the British, the Italian, and the French School. A reflective comparison between t

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