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
Thu Jan 20 2022
Journal Name
Webology
Information Sources and their Role in E-learning from Iraqi College Students’ Viewpoint
...Show More Authors

The study aims at identifying the sources of information and explaining their role in e-learning from the viewpoint of the Iraqi college students. The researchers relied on the descriptive method of the survey method to collect data and know the point of view of undergraduate students from the Department of Information in the College of Arts / Tikrit University and the Department of Quranic Studies at the College of Arts / University of Baghdad. The questionnaire was used as an instrument of the study, the research sample is (120) students; each section has (60) male and female students. The study concluded that there are many types and forms of information sources that students receive through electronic educational platforms from text con

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Mon Jan 01 2018
Journal Name
Aip Conference Proceedings
Indoor 222Rn measurement and hazards indices in houses of Al-Najaf province – Iraq
...Show More Authors

View Publication
Scopus (4)
Crossref (4)
Scopus Clarivate Crossref
Publication Date
Tue Dec 30 2008
Journal Name
Al-kindy College Medical Journal
Left Ventricular Hypertrophy in Diabetic Patients and Its Relation to Other Diabetic Complications
...Show More Authors

Background: left ventricular hypertrophy is independent risk factor for cardiovascular morbidity and mortality. The presence of diabetic complications such as autonomic neuropathy and retinopathy may predict cardiac structural changes in diabetic patients. Objective: To explore the chance of occurrence of left ventricular hypertrophy in diabetic patients and whether it is related to the presence of other diabetic complications. Methods: ninty seven (97) normotensive diabetic patients (57) type II with mean duration of diabetes of (12±6 y) and forty (40) type I with mean duration of (8±6 y) were studied by echocardiography and compared with 41 patients as control. Results: The LVMI was significantly higher in type II diabetics compared

... Show More
View Publication Preview PDF
Publication Date
Sat Dec 15 2018
Journal Name
Journal Of The College Of Education For Women
Camille Ben Ziad and his Place in the Arab-Islamic Heritage (Historical Study)
...Show More Authors

In a quick reading of the character of Camille Ben Ziad al-Nekha al-Kufi al-Taabi, one of the most sincere companions of Imam Ali (peace be upon him), he enjoyed great status and status because he was one of the people of his people who lived alongside Imam Ali (peace be upon him) since his tribe migrated from Yemen to Kufa To this end, he became loyal during the reign of Imam Ali (peace be upon him), who is also a member of the delegation coming from Kufa to protest against the actions of the Wali of Kufa during the reign of Caliph Uthman ibn Affan. After the death of Caliph Uthman bin Affan, (Peace and blessings of Allaah be upon him) (Duaa kamil), one of the most famous and important supplications in Islamic history, and each one of u

... Show More
View Publication Preview PDF
Publication Date
Tue Oct 22 2024
Journal Name
Hemoglobin
Prevalence and Molecular Characterization of β-Thalassemia in Kirkuk Province of Northern Iraq
...Show More Authors

View Publication
Scopus (1)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Wed Dec 08 2021
Journal Name
J. Inf. Hiding Multim. Signal Process.
Predication of Most Significant Features in Medical Image by Utilized CNN and Heatmap.
...Show More Authors

The growth of developments in machine learning, the image processing methods along with availability of the medical imaging data are taking a big increase in the utilization of machine learning strategies in the medical area. The utilization of neural networks, mainly, in recent days, the convolutional neural networks (CNN), have powerful descriptors for computer added diagnosis systems. Even so, there are several issues when work with medical images in which many of medical images possess a low-quality noise-to-signal (NSR) ratio compared to scenes obtained with a digital camera, that generally qualified a confusingly low spatial resolution and tends to make the contrast between different tissues of body are very low and it difficult to co

... Show More
View Publication Preview PDF
Scopus (2)
Scopus
Publication Date
Wed Jun 18 2025
Journal Name
Al-anbar Journal Of Veterinary Sciences
The relation between sex and Ectoparasites intestation of Albushlumbo Pseudapocrypte dentatus in Iraq
...Show More Authors

View Publication
Publication Date
Wed Sep 15 2021
Journal Name
Al-academy
Poster design and its role in drug control: باسم محمد صالح مهدي الخالدي
...Show More Authors

Our dear country faces many and varied challenges aimed at its history, civilization, its people, the scourge of drugs and psychotropic substances and their misuse. Therefore, we have a historical, ethical and professional responsibility to coordinate efforts and cooperation between all concerned to protect the Iraqi society from the threat of this scourge. Creative sources have varied in the variety of expressive means in politics, literature and the arts, in their style and technical treatment of various topics with innovative manifestations and intuitive interactive with visions as well as influences Psychological expressive descriptions of visual scene, it is one of the media and propaganda that contribute to the raising and developm

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed May 01 2013
Journal Name
Journal Of Computer Science
PROTOCOLS FOR SECURE ROUTING AND TRANSMISSION IN MOBILE AD HOC NETWORK: A REVIEW
...Show More Authors

Mobile ad hoc network security is a new area for research that it has been faced many difficulties to implement. These difficulties are due to the absence of central authentication server, the dynamically movement of the nodes (mobility), limited capacity of the wireless medium and the various types of vulnerability attacks. All these factor combine to make mobile ad hoc a great challenge to the researcher. Mobile ad hoc has been used in different applications networks range from military operations and emergency disaster relief to community networking and interaction among meeting attendees or students during a lecture. In these and other ad hoc networking applications, security in the routing protocol is necessary to protect against malic

... Show More
View Publication Preview PDF
Scopus (8)
Crossref (5)
Scopus Crossref
Publication Date
Thu Dec 09 2010
Journal Name
Journal Of Engineering
CORRELATIONS BETWEEN PHYSICAL AND MECHANICAL PROPERTIES OF AL-AMMARAH SOIL IN MESSAN GOVERNORATE
...Show More Authors

This paper describes the geotechnical properties of Al-Ammarah soil of Ammarah city in Messan Governorate-southern parts of Iraq. Data and other information taken from numbers of geotechnical reports that performed under the supervision of Consulting Engineering Bureau of Baghdad University. This research is devoted to study the correlation between different physical properties such as (LL, PI, LI, n,t, e) with different mechanical properties such as (qu, cc, cs, SPT). The correlation is verified using simple regression analysis. From the regression results it was found that there is direct correlation between different parameters. By using the correlation-with some information- preliminary investigation stages and studies of any s

... Show More