Preferred Language
Articles
/
ijs-2997
Enhancement of Spectrum Sensing Performance via Cooperative Cognitive Radio ‎Networks at Low SNR
...Show More Authors

     The inefficient use of spectrum is the key subject to overcome the upcoming spectrum crunch issue. This paper presents a study of performance of cooperative cognitive network via hard combining of decision fusion schemes. Simulation results presented different cooperative hard decision fusion schemes for cognitive network. The hard-decision fusion schemes provided different discriminations for detection levels. They also produced small values of Miss-Detection Probability at different values of Probability of False Alarm and adaptive threshold levels. The sensing performance was investigated under the influence of channel condition for proper operating conditions. An increase in the detection performance was achieved for cognitive users (secondary users) of the authorized unused dynamic spectrum holes (primary users) while operating in a very low signal-to-noise ratio  with the proper condition of minimum total error rate.

Scopus Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Jun 01 2010
Journal Name
Al-khwarizmi Engineering Journal
Land Use/Cover Change Analysis Using Remote Sensing Data: A Case Study, Zhengzhou Area, Henan Province, China
...Show More Authors

In the last two decades, arid and semi-arid regions of China suffered rapid changes in the Land Use/Cover Change (LUCC) due to increasing demand on food, resulting from growing population. In the process of this study, we established the land use/cover classification in addition to remote sensing characteristics. This was done by analysis of the dynamics of (LUCC) in Zhengzhou area for the period 1988-2006. Interpretation of a laminar extraction technique was implied in the identification of typical attributes of land use/cover types. A prominent result of the study indicates a gradual development in urbanization giving a gradual reduction in crop field area, due to the progressive economy in Zhengzhou. The results also reflect degradati

... Show More
View Publication Preview PDF
Publication Date
Sat Jan 12 2013
Journal Name
Pierb
RADAR SENSING FEATURING BICONICAL ANTENNA AND ENHANCED DELAY AND SUM ALGORITHM FOR EARLY-STAGE BREAST CANCER DETECTION
...Show More Authors

A biconical antenna has been developed for ultra-wideband sensing. A wide impedance bandwidth of around 115% at bandwidth 3.73-14 GHz is achieved which shows that the proposed antenna exhibits a fairly sensitive sensor for microwave medical imaging applications. The sensor and instrumentation is used together with an improved version of delay and sum image reconstruction algorithm on both fatty and glandular breast phantoms. The relatively new imaging set-up provides robust reconstruction of complex permittivity profiles especially in glandular phantoms, producing results that are well matched to the geometries and composition of the tissues. Respectively, the signal-to-clutter and the signal-to-mean ratios of the improved method are consis

... Show More
Publication Date
Thu Feb 07 2019
Journal Name
Iraqi Journal Of Laser
Tapered Splicing Points SMF-PCF-SMF Structure based on Mach-Zehnder interferometer for Enhanced Refractive Index Sensing
...Show More Authors

Photonic crystal fiber interferometers (PCFIs) are widely used for sensing applications. This work presented solid core-PCFs based on Mach-Zehnder modal interferometer for sensing refractive index. The general structure of sensor was applied by splicing short lengths of PCF in both sides with conventional single mode fiber (SMF-28).To apply modal interferometer theory collapsing technique based on fusion splicing used to excite higher order modes (LP01 and LP11). A high sensitive optical spectrum analyzer (OSA) was used to monitor and record the transmitted wavelength. This work studied a Mach-Zahnder interferometer refractive index sensor based on splicing point tapered SMF-PCF-SMF. Relation between refractive index sensitivity and tape

... Show More
View Publication Preview PDF
Publication Date
Tue Jan 08 2019
Journal Name
Iraqi Journal Of Physics
Estimation the blast wave pressure effecters by apply Remote Sensing (RS) and Geographic Information System (GIS) techniques
...Show More Authors

After the year 2003 terrorist attacks knock Baghdad city capital of Iraq using bomb explosion various, shook the nation, and made public resident of Baghdad aware of the need for better ways to protect occupants, assets, and buildings cause the terrorist gangs adopt style burst of blast to injury vulnerability a wider range form, and many structures will suffer damage from air blast when the overpressure concomitant the blast wave, (i.e., the excess over the atmospheric pressure 14.7 pounds per square inch at standard sea level conditions are about one-half pound per square inch or more(
to attainment injury. Then, the distance to which this overpressure level will extend depends primarily on the energy yield (§1.20) of the burst of

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Jan 01 2024
Journal Name
Fifth International Conference On Applied Sciences: Icas2023
Facial deepfake performance evaluation based on three detection tools: MTCNN, Dlib, and MediaPipe
...Show More Authors

View Publication
Scopus Crossref
Publication Date
Fri Jul 01 2022
Journal Name
Iraqi Journal Of Science
Study of Actual Jupiter Observation Days at UFRO Station During 2004 Year
...Show More Authors

In this Paper, There are attempts to compare the actual Observation Days in Decametric range (18-28 MHz), For Jupiter received by UFRO Earths’ station with the Prediction Observation Days that the Jupiter can be observed at Jupiter’s suitable location. The Jupiter’s Radio Observations actual data during year 2004, was taken from (Radio JOVE Data Archive website). The determination of the prediction days carried out by using the (Radio-Jupiter pro Jove Edition) software for Jupiter radio storms at UFRO station coordinates. Some Cases are considered according to Jupiter’s altitudes and Sun location at UFRO station Sky. The conclusion is, it could be found that there are (82) number of Predictions Observation Days, and It’s found

... Show More
View Publication Preview PDF
Publication Date
Tue Nov 30 2021
Journal Name
Iraqi Journal Of Science
Data integrity enhancement for the encryption of color images based on CRC64 technique using multiple look-up tables
...Show More Authors

Communication is one of the vast and rapidly growing fields of engineering, where
increasing the efficiency of communication by overcoming the external
electromagnetic sources and noise is considered a challenging task. To achieve
confidentiality for color image transmission over the noisy communication channels
a proposed algorithm is presented for image encryption using AES algorithm. This
algorithm combined with error detections using Cyclic Redundancy Check (CRC) to
preserve the integrity of the encrypted data. This paper presents an error detection
method uses Cyclic Redundancy Check (CRC), the CRC value can be generated by
two methods: Serial and Parallel CRC Implementation. The proposed algorithm for
the

... Show More
View Publication Preview PDF
Publication Date
Sat Oct 01 2011
Journal Name
Iraqi Journal Of Physics
Two dimensional grating and efficiency enhancement of Si photovoltaic cells by surface texturing using UV femtosecond laser pulses
...Show More Authors

A fast laser texturing technique has been utilized to produce micro/nano surface textures in Silicon by means of UV femtosecond laser. We have prepared good absorber surface for photovoltaic cells. The textured Silicon surface absorbs the incident light greater than the non-textured surface. The results show a photovoltaic current increase about 21.3% for photovoltaic cell with two-dimensional pattern as compared to the same cell without texturing.

View Publication Preview PDF
Publication Date
Wed Jan 01 2014
Journal Name
The Scientific World Journal
Heat Transfer Enhancement of Laminar Nanofluids Flow in a Circular Tube Fitted with Parabolic-Cut Twisted Tape Inserts
...Show More Authors

Numerical investigation has been carried out on heat transfer and friction factor characteristics of copper-water nanofluid flow in a constant heat-fluxed tube with the existence of new configuration of vortex generator using Computational Fluid Dynamics (CFD) simulation. Two types of swirl flow generator: Classical twisted tape (CTT) and Parabolic-cut twisted tape (PCT) with a different twist ratio (y= 2.93, 3.91 and 4.89) and different cut depth (w= 0.5, 1.0 and 1.5 cm) with 2% and 4% volume concentration

... Show More
View Publication
Scopus (34)
Crossref (26)
Scopus Clarivate Crossref
Publication Date
Tue Nov 09 2021
Journal Name
Energies
Natural Convection Effect on Solidification Enhancement in a Multi-Tube Latent Heat Storage System: Effect of Tubes’ Arrangement
...Show More Authors

The solidification process in a multi-tube latent heat energy system is affected by the natural convection and the arrangement of heat exchanger tubes, which changes the buoyancy effect as well. In the current work, the effect of the arrangement of the tubes in a multi-tube heat exchanger was examined during the solidification process with the focus on the natural convection effects inside the phase change material (PCM). The behavior of the system was numerically analyzed using liquid fraction and energy released, as well as temperature, velocity and streamline profiles for different studied cases. The arrangement of the tubes, considering seven pipes in the symmetrical condition, are assumed at different positions in the system, i

... Show More
View Publication
Scopus (12)
Crossref (9)
Scopus Clarivate Crossref