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 Aug 27 2020
Journal Name
European Journal Of Ophthalmology
Comparison of corneal epithelial thickness profile in dry eye patients, keratoconus suspect, and healthy eyes
...Show More Authors
Purpose:

To compare the corneal epithelial thickness profile in patients with dry eyes and keratoconus suspect with normal healthy eyes.

Methods:

The study involved 120 eyes with an age range from 19 to 30 years. Forty eyes had normal corneal topography and no dry eyes. Forty eyes had dry eyes but had normal corneal topography. The last 40 eyes were keratoconus suspect and had no symptoms or signs of dry eyes.

Results:

Central epithelial thickness was not different statistically for all eyes. ( p-value: 0.1). The superior epithelial thickness was 53.5 µm ±3.1 in the control

... Show More
View Publication
Scopus (17)
Crossref (18)
Scopus Clarivate Crossref
Publication Date
Wed Feb 28 2024
Journal Name
The Scientific World Journal
Leaf Extracts of Moringa oleifera Cultivated in Baghdad: Characterization and Antimicrobial Potential against Endodontic Pathogens
...Show More Authors

The use of medicinal plant preparations to clean and disinfect root canal infection is gaining popularity. The aim of this study was to evaluate the bioactive composition of leaf extracts of Moringa oleifera plants cultivated in Iraq (specifically Baghdad) and their antimicrobial activity against selected root canal pathogens for potential application in endodontic treatment. Materials and Methods. Moringa leaf extracts were prepared either through cold maceration or warm digestion techniques to perform an ethanolic or aqueous extraction, respectively. Phytochemical detection was performed before thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC) to measure flavonoids and phenolic compounds within both

... Show More
View Publication
Scopus (5)
Crossref (1)
Scopus Crossref
Publication Date
Sun Jan 01 2023
Journal Name
Revista Iberoamericana De Psicología Del Ejercicio Y El Deporte
EXPLORING THE MODELING OF SOCIO-TECHNICAL SYSTEMS IN THE FIELDS OF SPORT, ENGINEERING AND ECONOMICS
...Show More Authors

Scopus (26)
Scopus
Publication Date
Wed Sep 20 2017
Journal Name
Mechanical Sciences
Comparative experimental investigation and gap flow simulation in electrical discharge drilling using new electrode geometry
...Show More Authors

Abstract. This study presents experimental and numerical investigation on the effectiveness of electrode geometry on flushing and debris removal in Electrical Discharge Drilling (EDD) process. A new electrode geometry, namely side-cut electrode, was designed and manufactured based on circular electrode geometry. Several drilling operations were performed on stainless steel 304 using rotary tubular electrodes with circular and side-cut geometries. Drilling performance was characterized by Material Removal Rate (MRR), Electrode Wear Rate (EWR), and Tool Wear Ratio (TWR). Dimensional features and surface quality of drilled holes were evaluated based on Overcut (OC), Hole Depth (HD), and Surface Roughness (SR). Three-dimensional

... Show More
View Publication
Scopus (5)
Crossref (8)
Scopus Clarivate Crossref
Publication Date
Thu Sep 30 2021
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Mathematical Model, Simulation and Scale up of Batch Reactor Used in Oxidative Desulfurization of Kerosene
...Show More Authors

   In this paper, a mathematical model for the oxidative desulfurization of kerosene had been developed. The mathematical model and simulation process is a very important process due to it provides a better understanding of a real process. The mathematical model in this study was based on experimental results which were taken from literature to calculate the optimal kinetic parameters where simulation and optimization were conducted using gPROMS software. The optimal kinetic parameters were Activation energy 18.63958 kJ/mol, Pre-exponential factor  2201.34 (wt)-0.76636. min-1  and the reaction order 1.76636. These optimal kinetic parameters were used to find the optimal reaction conditions which

... Show More
View Publication Preview PDF
Crossref (11)
Crossref
Publication Date
Sun Dec 01 2013
Journal Name
Toxicon
Methods for simultaneous detection of the cyanotoxins BMAA, DABA, and anatoxin-a in environmental samples
...Show More Authors

View Publication Preview PDF
Scopus (35)
Crossref (34)
Scopus Clarivate Crossref
Publication Date
Fri May 01 2020
Journal Name
Indonesian Journal Of Electrical Engineering And Computer Science
Smart grid in the context of industry 4.0: an overview of communications technologies and challenges
...Show More Authors

The recent advances in technology, the increased dependence on electrical energy and the emergence of the fourth industrial revolution (Industry 4.0) were all factors in the increased need for smart, efficient and reliable energy systems. This introduced the concept of the Smart Grid (SG). A SG is a potential replacement for older power grids, capable of adapting and distributing energy based on demand. SG systems are complex. They combine various components and have high requirements for real time reliable operation. This paper attempts to provide an overview of SG systems, by outlining SG architecture and various components. It also introduces communication technologies, integration and network management tools that are involved in SG sys

... Show More
View Publication
Scopus (42)
Crossref (19)
Scopus Crossref
Publication Date
Sat Jul 01 2017
Journal Name
Journal Of Construction Engineering And Management
Identification, Quantification, and Classification of Potential Safety Risk for Sustainable Construction in the United States
...Show More Authors

View Publication
Scopus (54)
Crossref (50)
Scopus Clarivate Crossref
Publication Date
Wed Sep 01 2021
Journal Name
Baghdad Science Journal
Concentrations and Radiation Hazard Indices of Naturally Radioactive Materials for Flour Samples in Baghdad Markets
...Show More Authors

In the present work, Uranium (238U), Thorium (232Th) and Potassium (40K) specific activity concentration in (Bq/kg) was measured in five different types for wheat flours that are available in the Iraqi markets. The gamma spectrometry method with an NaI (Tl) detector has been used for radiometric measurements. Calculations of radium equivalent activity, annual effective dose equivalent, external hazard index (Hex), internal hazard index (Hin), representing gamma index and gamma dose rate in all  flour samples were 17.98132 Bq/kg, 0.0100334, 0.04502, 0.04857, 0.06872, 0.125883 and 8.181244 respectively. It is found that the average of specific activity concentration of wheat flour sam

... Show More
View Publication Preview PDF
Scopus (5)
Crossref (3)
Scopus Clarivate Crossref
Publication Date
Wed Jun 08 2022
Journal Name
Applied Sciences
Effect of Adjuvant, Concentration and Water Type on the Droplet Size Characteristics in Agricultural Nozzles
...Show More Authors

One of the goals of adding adjuvants to agricultural spray solutions is to enhance the droplet size characteristics of this spray. Droplet size, in turn, has an influence in the deposited spray quality, in addition to the drift and losses of spray to off-target places. The aim of this research was to evaluate the effect of adding adjuvants to two types of water from different sources on the droplet size characteristics. Two types of adjuvants were employed in the tests: the active substance content of the first adjuvant was a 50% aqueous solution of sodium salt of alkylbenzenesulfonic acid—10% (HY), whereas the second was from rapeseed oil (natural origin)—85% (OL). Both adjuvants were tested in two concentrations: the first was

... Show More
View Publication
Scopus (17)
Crossref (16)
Scopus Clarivate Crossref