Preferred Language
Articles
/
XYZ-soYBIXToZYAL3LHN
Connectivity and rendezvous in distributed DSA networks
...Show More Authors

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.

Scopus Crossref
Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
GENERATION AND TOOTH CONTACT ANALYSIS (TCA) OF HYPOID GEAR DRIVE
...Show More Authors

The present work covers the Face-Hobbing method for generation and simulation of meshing of Face hobbed hypoid gear drive. In this work the generation process of hobbed hypoid gear has been achieved by determination of the generation function of blade cutter. The teeth surfaces have been drawn depending on the simulation of the cutting process and the head cutter motion. Tooth contact analysis (TCA) of such gear drive is presented to evaluate analytically the transmission error function for concave and convex tooth side due to misalignment errors. TCA results show that the gear is very sensitive to misalignment errors and
the increasing of the gear teeth number decrease the transmission error for both concave and convex tooth sides a

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Sun Sep 06 2015
Journal Name
Baghdad Science Journal
Methionine as a Spacer between Poly Acrylic acid and Ampicillin
...Show More Authors

In this work a novel drug delivery system through modification of poly acrylic acid with Methionine as a spacer between the poly acrylic acid which was converted to its acyl chloride and reacted with Methionine as spacer unit which has been reacted with Ampicillin drug. In vitro drug release study had been conducted successfully in basic medium in pH 7.4 and acidic medium in pH 1.1 at 37?. Due to many problems associated with drug release and, this modification could decrease the side effect of drug. The prepared prodrug polymer was characterized by spectra method [FTIR and 1H?NMR]. Physical properties and intrinsic viscosity of drug polymer were determined. The good results were obtained in the presence of spacer unit with compar

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon May 27 2019
Journal Name
Al-khwarizmi Engineering Journal
Design and Implementation of SCADA System for Sugar Production Line
...Show More Authors

SCADA is the technology that allows the operator to gather data from one or more various facilities and to send control instructions to those facilities.  This paper represents an adaptable and low cost SCADA system for a particular sugar manufacturing process, by using Programmable Logic Controls (Siemens s7-1200, 1214Dc/ Dc/ Rly). The system will control and monitor the laboratory production line chose from sugar industry. The project comprises of two sections the first one is the hardware section that has been designed, and built using components suitable for making it for laboratory purposes, and the second section was the software as the PLC programming, designing the HMI, creating alarms and trending system. The system will ha

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Thu Dec 23 2010
Journal Name
Arabian Journal Of Geosciences
Climatic prediction of the terrestrial and coastal areas of Iraq
...Show More Authors

View Publication
Crossref (2)
Crossref
Publication Date
Wed Jun 20 2018
Journal Name
Al-academy
Cinematic Costumes Between the Function of Publicity and Semiotics Significance
...Show More Authors

    The cinematic costume is a qualitative element that transcends the direct function of it. It is an active personality that can become a brand of publicity and transformative signs that dismantle the intellectual system of acts, characters and events and reconstructs them aesthetically. For this reason, the researcher identified the subject of his research with the following address: (cinematic costumes between the function of publicity and Semiotics Significance). The researcher divided the research into the following: The methodological framework. The theoretical framework: The researcher divided it into three topics: the first topic: publicity. Function and concept. The second topic: fashion text and significance. Th

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Oct 31 2013
Journal Name
Al-khwarizmi Engineering Journal
Pressure Control of Electro-Hydraulic Servovalve and Transmission Line Effect
...Show More Authors

The effected of the long transmission line (TL) between the actuator and the hydraulic control valve sometimes essentials. The study is concerned with modeling the TL which carries the oil from the electro-hydraulic servovalve to the actuator. The pressure value inside the TL has been controlled by the electro-hydraulic servovalve as a voltage supplied to the servovalve amplifier. The flow rate through the TL has been simulated by using the lumped π element electrical analogy method for laminar flow. The control voltage supplied to servovalve can be achieved by the direct using of the voltage function generator or indirect C++ program connected to the DAP-view program built in the DAP-card data acqu

... Show More
View Publication Preview PDF
Publication Date
Thu Mar 11 2021
Journal Name
Annals Of Tropical Medicine & Public Health
Morphological and Molecular Study of Biofilm Formation by Enterobacter cloacae
...Show More Authors

Publication Date
Fri May 16 2014
Journal Name
International Journal Of Computer Applications
Design and Implementation of Real Time Face Recognition System (RTFRS)
...Show More Authors

View Publication
Crossref (6)
Crossref
Publication Date
Tue Jan 01 2019
Journal Name
Indian Journal Of Public Health Research & Development
Anterior Loop Presence and Extension Using Cone-Beam Computed Tomography
...Show More Authors

View Publication
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Tue Jun 22 2010
Journal Name
Journal Of Al-nahrain University
STUDY THE STRUCTURAL AND ELECTRICAL PROPERTIES OF CdTe:Ag THIN FILMS
...Show More Authors

The influence of silver doped n-type polycrystalline CdTe film with thickness of 200 nm and rate deposition of 0.3 nm.s -1 prepared under high vacuum using thermal co-evaporation technique on its some structural and electrical properties was reported. The X- ray analysis showed that all samples are polycrystalline and have the cubic zinc blend structure with preferential orientation in the [111] direction. Films doping with impurity percentages (2, 3, and 4) %Ag lead to a significant increase in the carrier concentration, so it is found to change from 23.493 108 cm -3 to 59.297 108 cm -3 for pure and doped CdTe thin films with 4%Ag respectively. But films doping with impurity percentages above lead to a significant decrease in the electrica

... Show More