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
Sun Dec 03 2017
Journal Name
Baghdad Science Journal
Construction and Operation of Solar Energy Dish for Water Heating
...Show More Authors

Construction and operation of (2 m) parabolic solar dish for hot water application were illustrated. The heater was designed to supply hot water up to 100 oC using the clean solar thermal energy. The system includes the design and construction of solar tracking unit in order to increase system performance. Experimental test results, which obtained from clear and sunny day, refer to highly energy-conversion efficiency and promising a well-performed water heating system.

View Publication Preview PDF
Scopus (1)
Scopus Crossref
Publication Date
Tue May 07 2019
Journal Name
Acm Journal On Emerging Technologies In Computing Systems
Neuromemrisitive Architecture of HTM with On-Device Learning and Neurogenesis
...Show More Authors

Hierarchical temporal memory (HTM) is a biomimetic sequence memory algorithm that holds promise for invariant representations of spatial and spatio-temporal inputs. This article presents a comprehensive neuromemristive crossbar architecture for the spatial pooler (SP) and the sparse distributed representation classifier, which are fundamental to the algorithm. There are several unique features in the proposed architecture that tightly link with the HTM algorithm. A memristor that is suitable for emulating the HTM synapses is identified and a new Z-window function is proposed. The architecture exploits the concept of synthetic synapses to enable potential synapses in the HTM. The crossbar for the SP avoids dark spots caused by unutil

... Show More
View Publication
Scopus (14)
Crossref (14)
Scopus Clarivate Crossref
Publication Date
Sun Jun 07 2015
Journal Name
Baghdad Science Journal
Association of Aquatic worms and infected snails with Digenean larvae
...Show More Authors

Six species of aquatic snails were sorted from three sites, the irrigation canal of Baghdad University campus (S1), River Tigris at Al-Za'afaraniah district / Baghdad(S2) , and River Euphrates at Al-Haideriah district Al-Najaf province(S2). The species included Melanopsis nodosa ;Melanoides tuberculata ; Thaiodaxsas jordani ; Lymnaea auricularia ; Physa acuta and Bellamya bengalensis. The first specis recorded the highest total number and was found in high density in the R. Euphrates site (S3), while the last species was the most widely distributed species, and found in all study sites. The last three species were found in Tigris river (S2) , while the first and last species were collected from the irrigation canal (S1).The result reveal

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
Preparation and diagnosis rules Leno complexes with Ortho Hyderoxa Benzldaaan
...Show More Authors

I attended the new chief base of bilateral interaction Para Amino like 1 Phenyl 4 Bayrosolin 5 Online with Alsalesl Aldehid someone Allicand by careful analysis of the elements and infrared spectrum

View Publication Preview PDF
Publication Date
Tue Dec 21 2021
Journal Name
Physical Chemistry Research
Photocatalytic and optical performances of CeO2 by substitution of titanium
...Show More Authors

In this contribution, density functional theory-based calculations have been carried out to assess the electronic, photocatalytic and optical properties of Ce1-xTixO2 system. Ti incorporation leads to a decrease of Ce 4f states and enhancement of Ti 3d states in the bottom of conduction band. Furthermore, it was found that doping ceria with Ti-like transition metals could evidently shift the absorption of pure CeO2 towards higher wavelength range. These findings can provide some new insights for designing CeO2-based photocatalysts with high photocatalytic performance. To the best of our knowledge, this investigation calculates Mullikan’s charge transfer of Ce1-xTixO2 system for the first time. Charge transfer reveals an ionic bond between

... Show More
Preview PDF
Publication Date
Sat Sep 01 2018
Journal Name
Journal Of Pharmaceutical Sciences And Research
Preparation and characterization of oro-dispersible tablets of bromhexine hydrochloride
...Show More Authors

Scopus (1)
Scopus
Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
Effect of frequency Chirp on the black and gray solitions
...Show More Authors

the behavior of the first-order black and gray solitons propagtedin optical fiber in the presence of frequency chirp is studied analytically and numerically results show that phase profile of black solitons changes abruptly

View Publication Preview PDF
Publication Date
Fri Dec 31 2021
Journal Name
Onkologia I Radioterapia
Correlation between mammographic appearance of breast cancer and histopathological results
...Show More Authors

Scopus
Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
Preparation and characterization of Activated Carbon from Iraqi Corns Stalks
...Show More Authors

In this paper, Activated Carbon was successfully prepared from local Iraqi material namely corns stalks .Zinc chloride ZnCl2 was used as activating agent with different concentrations (20%, 40%, 60%) for 72 hours. followed by carbonization at 450 C for (2) hour. UV-Spectrophotometer used for measuring absorbance of methylene blue solutions before and after adsorption. the maximum amount adsorbed for methylene blue material of the prepared activated Carbon was studied by Langmuir adsorption isotherm. Other characteristics of the resulting activated Carbon also discussed, such as pH, Moisture Content and ash content. Finally Activated carbon prepared in this work has good properties compared to the standard samples in such a way it could be

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jun 01 2008
Journal Name
Baghdad Science Journal
Preparation and Purification of natural uranium metal by Iodine method.
...Show More Authors

In this work ,glass-metal apparatus was designed and manufactured which used for preparing ahigh purity uranium. The reaction is simply take place between iodine vapour and uranium metal at 500C in closed system to form uranium tetra iodide which is decomposed on hot wire at high temperature around 1100C. Also another apparatus was made from Glass and used for preparing ahigh purity of UI4 more than 99.9% purity.

View Publication Preview PDF
Crossref