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.
Background: Oral Lichen Planus is a chronic inflammatory mucosal disease, presenting in various clinical forms .Both antigen-specific and non-specific mechanisms involved in the pathogenesis of OLP. Apoptosis or programmed-cell death is a physiological process essential for the normal development and maintenance of homeostasis in many organisms. Fas is a cell-surface glycoprotein, 40-kDa, that belongs to the nerve growth factor / tumor necrosis factor (TNF) receptor family. Fas is expressed in several tissues including blood, where its expression is upregulated on activated T and B lymphocytes and natural killer cells. Fas ligand is a type II transmembrane protein that belongs to the tumor necrosis factor family. The proto-oncogene c-Myc is
... Show MoreData <span>transmission in orthogonal frequency division multiplexing (OFDM) system needs source and channel coding, the transmitted data suffers from the bad effect of large peak to average power ratio (PAPR). Source code and channel codes can be joined using different joined codes. Variable length error correcting code (VLEC) is one of these joined codes. VLEC is used in mat lab simulation for image transmission in OFDM system, different VLEC code length is used and compared to find that the PAPR decreased with increasing the code length. Several techniques are used and compared for PAPR reduction. The PAPR of OFDM signal is measured for image coding with VLEC and compared with image coded by Huffman source coding and Bose-
... Show MoreCOVID-19 is a unique viral infectious illness that causes a variety of symptoms and health hazards, particularly to the respiratory system and has been declared a worldwide pandemic. The disease is characterized by a cytokine release in severe conditions. Interleukin-6 (IL-6), a proinflammatory cytokine, mediates an important immunomodulatory process. Also, vitamin D was identified to have a role in the innate immunity of individuals. Our study was designed to find the role of IL-6 and vitamin D in COVID-19 patients, as well as, to see whether there is a link between vitamin D deficiency and cytokine syndrome development. The study included 90 COVID-19 patients and 30 control people from Baghdad, Iraq. The age of the participants was non-s
... Show MoreTraction force and power requirement when performing primary tillage occupy the minds of almost farmers, this field research had aim to determine and calculate the pulling force of the most commonly used moldboard and chisel plows, the research conducted in silt clay loam for chisel and moldboard plows as the main factor, two depths of tillage 18 and 25 cm as a second factor and three speeds of tractor 2.55, 4.30 and 6.15 km.h-1 as a third factor. Moldboard plow recorded least traction force 7.550 kN, drawbar power 11.583 hp, power losses due to slippage 1.088 hp, power on the rear axle of the tractor 15.770 hp and brake horse power 17.495 hp. Chisel plow recorded best traction efficiency 76.217 % and total traction efficiency 68.659 %. Dep
... Show MoreThis field experiment, was conducted to investigate a comparison of two methods for harvesting potatoes: mechanical and handy when using moldboard and chisel plow for primary tillage and three different distances for planting tubers in the rows 15, 25, and 35 cm in silt clay loam soil south of Baghdad. The factorial experiment followed a randomized complete block design with three replications using L.S.D. 5 % and 1 %. Mechanical harvest recorded the best valid potato tubers at 88.78 %, marketable yield of 31.74 ton. ha-1, efficiency lifted 95.68 %, tubers damage index 28.41, speeding up the harvesting process and reducing time and effort. Handy harvest gave the least damage to potato tubers, 6.02 %, and unlifted potato tubers, 4.32 %. Howe
... Show MoreBackground: Semen contamination is a detrimental factor in decreasing fertility. Seasonal changes may affect the contamination, too. Objectives: This study was designed to detect semen contamination in ovine and caprine during different seasons. Methods: Six fully mature male sheep and goats were subjected to electro-ejaculator collection twice monthly from February 1, 2022, to January 31, 2023 (Spring, February 1, 2022-April 30, 2022; Summer, May 1, 2022, July 31, 2022; Autumn August 1, 2022, October 31, 2022; Winter November 1, 2022, January 31, 2023), for studying the seasonal effect. A total of 288 semen samples were collected from both species (36 samples from each per season). All samples were subjected to bacterial isolatio
... Show MoreIn the name of God, the Most Gracious, the Most Merciful
Praise be to God who revived Balu. And the good word brought hard hearts after removing from them what had almost killed them of ignorance, injustice, hatred, hostility, estrangement, and irritation... So God replaced for them what was best with what was best in terms of knowledge and fairness, and what was corrupt, love, and altruism. So the example of a believer and a good word is like a tree with good roots and branches. Then I pray and greet the one who watered it from the pure and inexhaustible spring of Islam, our Master Muhammad, so that the valleys flowed in their capacity, and the crops grew, then they became thicker and became even, and their good fruits in behavi
... Show MoreThe aim of this message to monitor this phenomenon throught the Quran , which is the constitution of the Islamic nation and Hariatha as well as to express kasalah integrity , justice honesty , patience , abd pacr .
We feel this vocabulary to hight athical values advocated by the Quran and the need to build commitment to the orthodox society free of corruption that leads ta a disorder of the human society .
The outcome of the study the researcher found that faith to a number of results was most notably the advent of righteusness in the Holy Quran meaning of comprehensive RPR spacious field and breadth Maadenh .
The research is a special case of semantics modern Iraqi art, especially with regard to the art of sculpture, and the exact Nasba sculpture, has included research, four chapters on whale1. The first chapter: which consisted of:A. The research problem.B. The importance of research.C. Find goal.H. Find borders.Kh. Determine the terms.2. Chapter II: The theoretical framework: which consisted ofA. The first topic: sculptured configuration.B. The second topic:1. The first axis: contemporary Iraqi sculpture.2. The second axis: the sculptor Jawad Salim.3. The third axis: Mohammed sculptor debateC. Theoretical framework indicators.D. Previous studies.3. Chapter III: proceedings: which included:A. Find community.B. The research sample.C. Research
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