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
Tue Jul 07 2020
Journal Name
Journal Of Mechanical Engineering Research & Developments
Occupational noise and its effects on Baghdad airport workers
...Show More Authors

The problem of noise in the Baghdad airport has been examined in this study; and noise measurement and survey studies have been carried out at four high noise level (operation, training and development, quality system, and information and technology) zones located in this region. Noise exposure is a common hazard to workforce in general although at varying degrees depending on the occupation, as many workers are exposed for long periods of time to potentially hazardous noise. A questionnaire was completed by 122 workers during this study in order to determine the physical, physiological, and psycho-social impacts of the noise on workers and to specify what kind of measurements have been taken both by the employers and workers for protection

... Show More
View Publication Preview PDF
Publication Date
Fri Feb 14 2020
Journal Name
Journal Of Mechanical Engineering Research And Developments
Occupational Noise and Its Effects on Baghdad Airport Workers
...Show More Authors

The problem of noise in the Baghdad airport has been examined in this study; and noise measurement and survey studies have been carried out at four high noise level (operation, training and development, quality system, and information and technology) zones located in this region. Noise exposure is a common hazard to workforce in general although at varying degrees depending on the occupation, as many workers are exposed for long periods of time to potentially hazardous noise. A questionnaire was completed by 122 workers during this study in order to determine the physical, physiological, and psycho-social impacts of the noise on workers and to specify what kind of measurements have been taken both by the employers and workers for protection

... Show More
Publication Date
Wed Dec 01 2010
Journal Name
Desalination And Water Treatment
Removal of lead, cadmium, and mercury ions using biosorption
...Show More Authors

View Publication
Scopus (31)
Crossref (21)
Scopus Clarivate Crossref
Publication Date
Wed Feb 20 2019
Journal Name
Iraqi Journal Of Physics
The solar eclipse and its relation with higree months
...Show More Authors

The solar eclipse occurs at short time before the crescent birth moment when the moon near any one of moon orbit nodes It is important to determine the synchronic month which is used to find Higree date. The 'rules' of eclipses are: 

Y= ± 0.997  of Earth radius , the solar eclipse is central and 0.997 < |Y| < 1.026 the umbra cone touch the surface of the Earth, where Y is the least distance from the axis of the moon's shadow to the center of the Earth in units of the equatorial radius of the Earth.

A new model have been designed, depend on the horizontal coordinates of the sun, moon, the distances Earth-Moon (rm), Earth-sun (rs) and |Y| to determine the date and times of total solar eclipse and the geogra

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Feb 28 2021
Journal Name
Journal Of Economics And Administrative Sciences
Evaluation of Educational Performance according to Centralization and Decentralization
...Show More Authors

The research aims to identify the effect of applying administrative decentralization to an educational performance by assessing educational performance before and after the process of transferring powers from the federal government (the Iraqi Ministry of Education) to local governments (governorates) as well as identifying the appropriate central or decentralized administrative system to advance the educational reality and performance. To achieve the goal of the research, educational data was collected and analyzed, as well as the measurement of educational performance indicators and analysis during two phases, the first represents the stage of applying the central system and spanned between the academic year (2011-2012) and the

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Jan 20 2025
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Assessing Landsat Processing Levels and Support Vector Machine Classification
...Show More Authors

The availability of different processing levels for satellite images makes it important to measure their suitability for classification tasks. This study investigates the impact of the Landsat data processing level on the accuracy of land cover classification using a support vector machine (SVM) classifier. The classification accuracy values of Landsat 8 (LS8) and Landsat 9 (LS9) data at different processing levels vary notably. For LS9, Collection 2 Level 2 (C2L2) achieved the highest accuracy of (86.55%) with the polynomial kernel of the SVM classifier, surpassing the Fast Line-of-Sight Atmospheric Analysis of Spectral Hypercubes (FLAASH) at (85.31%) and Collection 2 Level 1 (C2L1) at (84.93%). The LS8 data exhibits similar behavior. Conv

... Show More
View Publication
Publication Date
Sun Jun 02 2013
Journal Name
Baghdad Science Journal
Synthesis and Characterizationof Some New Phenolic Schiff Bases Derivatives
...Show More Authors

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).

View Publication Preview PDF
Crossref
Publication Date
Thu Aug 03 2023
Journal Name
Journal Of Kufa For Mathematics And Computer
Category Theory and New Classes of Semi Bornological Group
...Show More Authors

Publication Date
Mon Jun 30 2003
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Extraction and Purification of Magnesium Sulphate from Iraqi Dolomite
...Show More Authors

View Publication Preview PDF
Publication Date
Sun Dec 31 2023
Journal Name
College Of Islamic Sciences
Fuzuli al-Baghdadi, his purposes and his poetic arts
...Show More Authors

This research is mainly about the Arabic poetical work of the poet “Fadhuli AL-Baghdadi ». It aims to show the poetic purposes used like (advice, flirting and praise). This research sheds some lights on how the poetical work was hardly found because it has only one copy, which is originally a transcript

This study analyses AL-Baghdadi's poems, as well as Sheding some lights on earlier life and his other compositions, AL-Baghdadi is considered a tri-lingual poet who wrote in Turkish, Arabic and persian. His Surname as "AL- Baghdadin was as mentioned by some historians, due to his being born in Baghdad or to All a resident in Baghdad at that some poets, who wrote in Arabic have been mentioned here also, like The judge Burhan Al-

... Show More
View Publication Preview PDF