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.
Two groups of chronic hepatitis B and C virus patients were divided into Pre-treated patients (25 CHB patients with positive HBs Ag for more than 6 months and 40 CHC patients), and post-treated patients [12 CHB patients (4, 6, and 2 were treated with lamivudine, IFN-? and combination of LMV + IFN-? respectively), and 27 patients for CHC (3, 13 and 11 patients were treated with Ribavirin, IFN-? and combination therapy (RBV+ IFN-?) respectively].These patients were followed up for 6 months. By using ELISA technique, levels of IL-6, IL-10, IFN-? and TNF-? were measured in vivo and in vitro (supernatant of PBMCs stimulated with PHA) and compared with healthy control. The mean level of IL-6, IL-10 and TNF-? in CHB patients showed significant dif
... Show MoreThe study aimed to reveal the degree of inclusion of media concepts in the books of social and national studies in general education in light of the criteria of media education and the nature of the Saudi society. Additionally, to identify the estimations of the participants in the study of the importance of including media concepts in these books, and to build a matrix of the range and sequence of media concepts in the books of social and national studies in the grades of Saudi general education. The study followed the descriptive approach in both descriptive analysis of the textbooks and descriptive survey of the study participants who were (203) students in the schools of boys and girls in general education in Makkah. The study used t
... Show MoreLanguage is essential for politics, for producing, disseminating, engaging with, and reacting to political discourse. The pragmatics of political speeches is crucial to the development of effective political communication tactics. Thus, speech is situated at the intersection of rhetoric, linguistics, and politics. In communication, intent is a pragmatic factor that plays a crucial role at the time of the communication process. Speech is of paramount importance to the social and political domains. Through the use of concepts and the relationship between language and politics, the study analyzes the function of language in communication and interpretation of intentions. The study of the relationships between language and the situations in whi
... Show MoreThe study of the concepts of "democracy" and "human rights" and their impact on development, has taken a prominent place in the context of general political and cultural concerns, or in specialized studies even though researchers and scholars do not agree on defining the concepts: Democracy, Human Rights, Development or deriving a global definition hindering them, and that because of the importance of this topic, which proceeds from a number of considerations standing in the forefront, of which:
First: What the world witnesses today in the first decade of this century of consecration of the unipolar theory, trying to give its concepts and perceptions through the law ((excessive force)) to the power of international
... Show MoreGender mainstreaming is a goal for building a society characterized by justice and equality. Gender mainstreaming requires a clear understanding of the concept. Therefore, the research focuses on the concept of gender and how it was addressed in the literature through which the concepts related to gender were extracted which is represented by the role and social status through which the relationship of gender can be measured. In order to find out the basis for the different status and roles of both sexes in societies, the interpreted theories of gender were addressed, through which the most important factors affecting gender relations, such as biological, social and economic factors, as well as political systems, were discussed. Due to t
... Show MoreThe importance of the heritage of the Iraqi heavy symbolism and connotations where contacted habits rights and beliefs from antiquity to the present, in addition to being represented with data aesthetic it is an expression philosophical concepts associated implications incentives cultural aesthetic of the content of the intellectual including contents of semantics and symbols and the dimensions of the meanings Sayings , to turn form a legacy popularly moving window to communicate worth studying its details and search function on the character and identity and origins . Where have emerged in recent years, a phenomenon characterized by inventing new designs by modernist styles that have entered into technical system design and effectivenes
... Show MoreAbstract\
Dealing economic units at the present time with an industrial environment characterized by competitiveness and the pace of change and its strength as a result of this changing environment shall be on those who made it to adopt strategies that allow them to confront these variables and work in order to meet the market requirements of quality and price appropriate products to suit and the demand for those products and conditions to maintain
its competitive position and its development.
As a result, it became the subject of competitiveness in recent years and enjoys widespread attention at the global level. And in order to keep up
... Show MoreThe decorative supplements added are important factors in determining many decorative effects and how to implement them, whether in fabrics or fashion, and also work to determine the nature of perception for both the designer and the recipient and have a key role in shaping the human personality and determining his motives and emotional tendencies in the acquisition of fabrics and fashion and the vocabulary they carry A design that has certain connotations and symbols that gain its value from the effects it leaves on the physical formations of women. The problem of the research came with the following question (What are the decorative supplements and their role in the designs of fabrics and women’s fashion?) The research also dealt wit
... Show MoreThe aim of the study is to diagnose the real level of technology usage in teaching and learning EFL at university from teachers and students’ viewpoints, and see if it is possible to achieve something of the researchers’ dream - accessing top universities. Two questionnaires have been used to measure the range of technology usage in Colleges of Education for Women, Baghdad and Iraqi Universities, and College of Basic Education. The results have shown that the reality of using technology is still away from the dream. The results have been ascribed to two reasons: The first is the little knowledge of using technology in teaching, and the second is that technology is not included in the curriculum.
NAA Mustafa, University of Sulaimani, Ms. c Thesis, 2010 - Cited by 4