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 in

The development of human resources training programs can assist in agreat deal in creating products of high quality with quantitive advantage for the economicunit;through the sale of products by prices higher of the peer products price in the arket,or decreasing production costs which lead into increusing the unet  profits. for these reasons, the human resources have got great importance for their great role in  any economy,and they havestarled to consentrate on accounting these resource.From this point of view, this research has handied human resources accounting and their effect on quality costs.  In(MID-Refinery Company),quality costs are determined ,then we have larified the reality of training and development in the o

The optimum separators operating pressure is determined by using flash calculations and equilibrium ratios. In this study, the optimum separator size for Jambur field is calculated by using equations introduced by Arnold and Stewart and API12J Specification [1]. Because Jambur field has a high production rate two conditions are taken in the study to determine separator size, first based on production rate 80,000 bbl/day and second based on split the production between two banks A and B (40,000 bbl/day for each bank). The calculation resulted in optimum separator pressure for the first stage of 700 psi, and the second stage of 300 psi, and the third stage of 120 psi. The results show that as the number of stages increased above three

The architecture of the richly decorated mosques demonstrated that the Islamic culture is one of the most significant and greatest civilizations in the history of humanity. The plant decorative units are one of the key areas in which the Muslim artist excelled. As a result, he created various plant forms that he took from nature, which led him to invent the arabesque art consisting of plant motifs with curved and rounded lines or wrapped between them. These shapes with curved borders include leaves, twigs, and flowers. Buildings and artefacts from the nineteenth century AD have this shape. they achieved their objectives during the twelfth and thirteenth centuries. There was another kind of vegetable decorative unit, made up of stems and

Starting from bis (4,4'-diamino phenoxy) ethan(1), a variety of phenolicschiff bases (methylolic, etheric, epoxy) derivatives have been synthesized. All proposed structure were supported by FTIR, 1H-NMR, 13C-NMR Elemental analysis, some derivatives evaluated by thermal analysis (TGA).

(1) Background: Sleeping disorders are frequently reported following traumatic brain injury (TBI). Different forms of sleeping disorders have been reported, such as sleepiness, insomnia, changes in sleeping latency, and others. (2) Methods: A case-control study with 62 patients who were victims of mild or moderate TBI with previous admissions to Iraqi tertiary neurosurgical centers were enrolled as the first group, and 158 patients with no history of trauma were considered as the control. All were 18 years of age or older, and the severity of the trauma and sleep disorders was assessed. The Pittsburgh sleep quality index was used to assess sleep disorders with average need for sleep per day and average sleep latency were assessed in

In light of what constitutes the cultural factor from a great importance in the context of the incorporation of an active and participant civil society in the process of democracy- building and the achievement of political development, this article tries to look at the concept of the political culture and the civil society with the stand on the nature of existing relationship between them in its theoretical part, then the move to dissection of the civil society crisis in Algeria under the prevalent cultural values for understanding the relationship between the two variables in its empirical part, as a step towards the detection on the pivoting of democratic values in activating the political participation and attainment the democratic co

The aim of this research is to compare traditional and modern methods to obtain the optimal solution using dynamic programming and intelligent algorithms to solve the problems of project management.

It shows the possible ways in which these problems can be addressed, drawing on a schedule of interrelated and sequential activities And clarifies the relationships between the activities to determine the beginning and end of each activity and determine the duration and cost of the total project and estimate the times used by each activity and determine the objectives sought by the project through planning, implementation and monitoring to maintain the budget assessed