Preferred Language
Articles
/
joe-2010
ADAPTIVE CYCLIC PREFIX LENGTH FOR CONVOLUITIONAL CODE OFDM SYSTEM IN FREQUENCY SELECTIVE CHANNEL
...Show More Authors

Orthogonal Frequency Division Multiplexing (OFDM) is one of recent years multicarrier modulation used in order to combat the Inter Symbol Interference (ISI) introduced by frequency selective mobile radio channel. The circular extension of the data symbol, commonly referred to as cyclic prefix is one of the key elements in an OFDM transmission scheme. This paper study The influence of the cyclic prefix duration on the BER performance of an OFDM-VCPL (Orthogonal frequency division multiplexing - Variable Cyclic Prefix Length) system and the conventional OFDM system with frame 64-QAM modulation is evaluated by means of computer simulation in a multipath fading channel. The adaptation of CP is done with respect to the delay spread estimation of the channel.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Dec 11 2014
Journal Name
Sensors
Automatic Frequency Controller for Power Amplifiers Used in Bio-Implanted Applications: Issues and Challenges
...Show More Authors

With the development of communication technologies, the use of wireless systems in biomedical implanted devices has become very useful. Bio-implantable devices are electronic devices which are used for treatment and monitoring brain implants, pacemakers, cochlear implants, retinal implants and so on. The inductive coupling link is used to transmit power and data between the primary and secondary sides of the biomedical implanted system, in which efficient power amplifier is very much needed to ensure the best data transmission rates and low power losses. However, the efficiency of the implanted devices depends on the circuit design, controller, load variation, changes of radio frequency coil’s mutual displacement and coupling coef

... Show More
View Publication
Scopus (21)
Crossref (17)
Scopus Clarivate Crossref
Publication Date
Tue Aug 02 2022
Journal Name
Karbala International Journal Of Modern Science
Performance Simulation for Adaptive Optics Technique Using OOMAO Toolbox
...Show More Authors

The Adaptive Optics technique has been developed to obtain the correction of atmospheric seeing. The purpose of this study is to use the MATLAB program to investigate the performance of an AO system with the most recent AO simulation tools, Objected-Oriented Matlab Adaptive Optics (OOMAO). This was achieved by studying the variables that impact image quality correction, such as observation wavelength bands, atmospheric parameters, telescope parameters, deformable mirror parameters, wavefront sensor parameters, and noise parameters. The results presented a detailed analysis of the factors that influence the image correction process as well as the impact of the AO components on that process

View Publication
Scopus (6)
Crossref (1)
Scopus Crossref
Publication Date
Thu Nov 02 2023
Journal Name
Journal Of Engineering
An Improved Adaptive Spiral Dynamic Algorithm for Global Optimization
...Show More Authors

This paper proposes a new strategy to enhance the performance and accuracy of the Spiral dynamic algorithm (SDA) for use in solving real-world problems by hybridizing the SDA with the Bacterial Foraging optimization algorithm (BFA). The dynamic step size of SDA makes it a useful exploitation approach. However, it has limited exploration throughout the diversification phase, which results in getting trapped at local optima. The optimal initialization position for the SDA algorithm has been determined with the help of the chemotactic strategy of the BFA optimization algorithm, which has been utilized to improve the exploration approach of the SDA. The proposed Hybrid Adaptive Spiral Dynamic Bacterial Foraging (HASDBF)

... Show More
View Publication Preview PDF
Scopus Crossref
Publication Date
Sat Oct 01 2011
Journal Name
Journal Of Engineering
EMBEDDED LENGTH OF STEEL BARS IN SELF COMPACTED CONCRETE (SCC)
...Show More Authors

Experimental research was carried out on eight reinforced concrete beams to study the embedded length of the longitudinal reinforcement. Six beams were casted using self compacted concrete, and the two other beams were casted using normal concrete. The test was carried out on beams subjected to two point loads. The strain and the slip of the main reinforcement have been measured by using grooves placed during casting the beams at certain places. The measured strain used to calculate the longitudinal stresses (bond stress) surrounding the bar reinforcement, The study was investigated the using of self compacted concrete SCC on the embedded length of reinforcing bars, and comparing the results with normal concrete. The test results show th

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Dec 01 2013
Journal Name
Baghdad Science Journal
Construction of New Ion Selective Electrodes for Determination Fe(III) and Their Application in Pharmaceutical samples
...Show More Authors

Liquid membrane electrodes for the determination iron(III) were constructed based on chloramphenicol sodium succinate and iron(III) CPSS-Fe(III) as ion pair complex, with four plasticizers Di-butyl phosphate (DBP); Di-butyl phthalate (DBPH); Di-octyl phthalate (DOP); Tri-butyl phosphate (TBP); in PVC matrix . These electrodes give Nernstian and sub-Nernstian slopes (19.79, 24.60, 16.01 and 13.82mV/decade) and linear ranges from (1x10-5-1x10-2 M, 1x10-5-1x10-2 M, 1x10-6-1x10-2 M and 1x10-5-1x10-2 M) respectively. The best electrode was based on DBP plasticizer which gave a slope 19.79 mV/decade, correlation coefficient 0.9999, detection limit of 9×10-6 M, lifetime 37 day displayed good stability and reproducibility and used to determine

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Dec 01 2023
Journal Name
Baghdad Science Journal
Fabrication of PVC Enrofloxacin-Selective Electrodes for Estimating Enrofloxacin in Pure Form and as Preparation Formula:
...Show More Authors

This study explored the development and qualities of the response of electrochemical properties of enrofloxacin-selective electrodes using precipitation based on producing phosphotungstic, after utilizing a matrix of polyvinyl chloride (PVC) and dibutyl phthalate or dibutyl phosphate as a plasticizer. The resulting membrane sensors were an enrofloxacin-phosphotungstic electrode (sensors 1) and an ENR-DOP-PTA electrode (sensors 2). Linear responses of (ENR-DBPH-PTA) and (ENR-DOP-PTA) within the concentration ranges of 2.1×10-6-10-1 and 3.0×10-6-10-2 mol. L-1, respectively, for both sensors were observed. Slopes of 51.61±0.24 and 39.40± 0.16 mV/decade and pH ranges equal to 2.5-8.5

... Show More
View Publication Preview PDF
Scopus Crossref
Publication Date
Fri Dec 01 2023
Journal Name
Iop Conference Series: Earth And Environmental Science
Relationship Study Between Total Length with Otolith Length and Thickness in Two Fish Species: Coptodon zillii (Gervais,1848) and Cyprinus carpio” (Linnaeus,1758)
...Show More Authors
Abstract<p>This study aimed new indications that may clarify the relationships between the total and standard lengths, and the length of the otolith, as well as the thickness and weight of these bones compared to the body weights of two different species of invasive fish in the Iraqi aquatic environment, the common carp <italic>Cyprinus carpio</italic> of the Cyprinidae family, and the common Tilapia. <italic>Coptodon zillii</italic>, from the Cichlidae family. The results showed that the otolith were not related to some of the vital characteristics of the studied fish, and there were differences in the correlation coefficient between some vital measurements with high signifi</p> ... Show More
View Publication Preview PDF
Scopus (2)
Crossref (2)
Scopus Crossref
Publication Date
Fri Jun 01 2007
Journal Name
Journal Of The College Of Languages (jcl)
L’alternance codique ou le code switching dans l’échange verbal
...Show More Authors

Le mot anglais code switching ou l’équivalent français alternance codique est un terme très utilisé dans des recherches qui traitent des problèmes en sociolinguistique. Le bilingue dispose, dans son répertoire linguistique, de moyens de communication qui lui permettent d’adapter son langage à des situations de communication plus variées que ceux du monolingue. Le code-switching ou l’alternance codique qui est un lieu de structuration de stratégies de communication en est un moyen indispensable.
L’alternance codique dans la conversation est l’utilisation d’un mot ou plus appartenant à une langue B à l’intérieur d’une phrase qui appartient à une langue A. Dans la plupart des cas, le locuteur se sert de l’a

... Show More
View Publication Preview PDF
Publication Date
Sat Mar 01 2025
Journal Name
Wasit Journal Of Engineering Sciences
Blue Laser Underwater Optical Visible Light Communication Using Recursive OFDM
...Show More Authors

Water covers more than 75% of the earth's surface in the form of the ocean. The ocean investigation is far-fetched because the underwater environment has distinct phenomenal activities. The expansion of human activities inside underwater environments includes environmental monitoring, offshore field exploration, tactical surveillance, scientific data collection, and port security. This led to increased demand for underwater application communication systems. Therefore, the researcher develops many methods for underwater VLC Visible Light Communications. The new technology of blue laser is a type of VLC that has benefits in the application of underwater communications. This research article investigated the benefits of underwater blu

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Apr 18 2013
Journal Name
International Journal Of Computer Applications
Design and Simulation of Hartley based Multi Orthogonal Band OFDM
...Show More Authors

Recent advances in wireless communication systems have made use of OFDM technique to achieve high data rate transmission. The sensitivity to frequency offset between the carrier frequencies of the transmitter and the receiver is one of the major problems in OFDM systems. This frequency offset introduces inter-carrier interference in the OFDM symbol and then the BER performance reduced. In this paper a Multi-Orthogonal-Band MOB-OFDM system based on the Discrete Hartley Transform (DHT) is proposed to improve the BER performance. The OFDM spectrum is divided into equal sub-bands and the data is divided between these bands to form a local OFDM symbol in each sub-band using DHT. The global OFDM symbol is formed from all sub-bands together using

... Show More
View Publication Preview PDF
Crossref (1)
Crossref