Preferred Language
Articles
/
BRcLWpIBVTCNdQwCTq3L
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 coefficients. This paper provides a comprehensive survey on various power amplifier classes and their characteristics, efficiency and controller techniques that have been used in bio-implants. The automatic frequency controller used in biomedical implants such as gate drive switching control, closed loop power control, voltage controlled oscillator, capacitor control and microcontroller frequency control have been explained. Most of these techniques keep the resonance frequency stable in transcutaneous power transfer between the external coil and the coil implanted inside the body. Detailed information including carrier frequency, power efficiency, coils displacement, power consumption, supplied voltage and CMOS chip for the controllers techniques are investigated and summarized in the provided tables. From the rigorous review, it is observed that the existing automatic frequency controller technologies are more or less can capable of performing well in the implant devices; however, the systems are still not up to the mark. Accordingly, current challenges and problems of the typical automatic frequency controller techniques for power amplifiers are illustrated, with a brief suggestions and discussion section concerning the progress of implanted device research in the future. This review will hopefully lead to increasing efforts towards the development of low powered, highly efficient, high data rate and reliable automatic frequency controllers for implanted devices.

Scopus Clarivate Crossref
View Publication
Publication Date
Tue Mar 01 2022
Journal Name
Iraqi Journal Of Physics
Simulation of Small Radio Telescope Antenna Parameters at Frequency of 1.42 GHz
...Show More Authors

The paper presents an overview of theoretical aspects of small radio telescope antenna parameters. The basic parameters include antenna beamwidth, antenna gain, aperture efficiency, and antenna temperature. These parameters should be carefully studied since they have vital effects on astronomical radio observations. The simulations of antenna parameters were carried out to assess the capability and the efficiency of small radio telescopes to observe a point source at a specific frequency. Two-dimensional numerical simulations of a uniform circular aperture antenna are implemented at different radii. The small diameter values are chosen to be varied between (1-10) m. This study focuses on a small radio telescope with a diameter of 3 m sin

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Sun May 21 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Antimicrobial Activities of Aqueous and Methanolic Extracts from Salvia officinalis and Salix acmophylla Used in the treatment of wound infection isolates
...Show More Authors

    The aqueous and methanol extracts of Salvia officinals and Salix acmoplylla traditionally used for the treatment of infections disease were tested for their active  against gram positive and gram negative bacteria isolated from wound  infection culture using the broth dilution and disc diffusion melhod. Results of   this study revealed the prescence of phytochemical which were  active  against gram positive and negative bacteria. Methanol extracts of both plants showed  the highest activity other the aqueous extract. The minimum inhibitory concentration (MIC) of the aqueous extracts on the test organism was  25- 100 mg\ml,while that of the  methanol extract was ranged betwee

... Show More
View Publication Preview PDF
Publication Date
Sat Dec 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Multiplicity of Accounting Concepts and it’s Impact on Thinking and Practical Applications
...Show More Authors

Accounting profession has been survived for long time and expected to survive in future, with out basing on theory in the field of practical practice . But there are numerous problems which emerge from the practical practice, their solution needs to be based on generally accepted accounting theory. The results of the researches in this field since the beginning of the last century unfolded the difficulty of formulating theory in accounting , but possible to formulate several accounting

مجلة العلوم الاقتصادية والإدارية

المجلد 18

العدد 69

الصفحات  318-  332  

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Jun 01 2022
Journal Name
Eurasian Chemical Communications
Characterization and synthesis of some new Schiff bases and their potential applications
...Show More Authors

In this present work, [4,4`-(biphenyl-4,4`-diylbis(azan-1-yl-1-ylidene))bis(methan-1-yl-1-ylidene)bis(2-methoxyphenl)(A1),4,4`-(biphenyl-4,4`-diylbis(azan-1-yl-1-ylidene))bis(methan-1-yl-1-ylidene)diphenol(A2),1,1`-(biphenyl-4,4`-diylbis(azan-1-yl-1-ylidene))bis(methan-1-yl-1-ylidene) dinaphthalen-2-ol (A3)]C.S was prepared in 3.5% NaCl. Corrosion prevention at (293-323) K has been studied by using electrochemical measurements. It shows that the utilized inhibitors are of mixed type based on the polarization curves. The results indicated that the inhibition efficiency changes were used with a change according to the functional groups on the benzene ring and through the electrochemical technique. Temperature increases with corrosion current

... Show More
View Publication Preview PDF
Scopus (7)
Scopus Clarivate
Publication Date
Tue May 01 2018
Journal Name
Journal Of Physics: Conference Series
Multispectral and Panchromatic used Enhancement Resolution and Study Effective Enhancement on Supervised and Unsupervised Classification Land – Cover
...Show More Authors

View Publication
Scopus (1)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Tue Jun 01 2021
Journal Name
Minar International Journal Of Applied Sciences And Technology
STRUCTURAL AND ELECTRICAL PROPERTIES OF (CDO)1-X (V2O5)X PREPARED BY PULSE LASER DEPOSITION TECHNIQUE FOR SOLAR CELL APPLICATIONS
...Show More Authors

In this work ,pure and doped(CdO)thin films with different concentration of V2O5x (0.0, 0.05, 0.1 ) wt.% have been prepared on glass substrate at room temperature using Pulse Laser Deposition technique(PLD).The focused Nd:YAG laser beam at 800 mJ with a frequency second radiation at 1064 nm (pulse width 9 ns) repetition frequency (6 Hz), for 500 laser pulses incident on the target surface At first ,The pellets of (CdO)1-x(V2O5)x at different V2O5 contents were sintered to a temperature of 773K for one hours.Then films of (CdO)1-x(V2O5)x have been prepared.The structure of the thin films was examined by using (XRD) analysis..Hall effect has been measured in orded to know the type of conductivity, Finally the solar cell and the effici

... Show More
View Publication
Crossref
Publication Date
Mon Mar 02 2009
Journal Name
Albahith Alalami
Types, contents and scientific research methods used in public relations research at the College of Mass Communication 1989 - 2007.
...Show More Authors

This study deals with knowing the types of research in public relations studies at the Faculty of Mass Communication for the period from 1989 to 2007 and knowing the methods that researchers used in their studies, as well as knowing the methods and tools of scientific research that were used, and whether one method or tool is used more than others, and knowing Samples used in the analysis. As well as the contents and types of this research The institutions that were subjected to the study, and the preparation of the respondents This research aims to answer the following questions:. A- What are the types of research and methods that were used in university theses that dealt with the topic? Public Relations at the Faculty of Media from 1989

... Show More
Publication Date
Tue Sep 05 2023
Journal Name
Migration Letters
The Impact of Climate Change on the Increase in the Frequency of Drought in the Eastern Region of Iraq
...Show More Authors

Aim: This abstract aims to highlight the critical nature of climate change as a pressing challenge facing humanity in the 21st century. It underscores the severe consequences it poses to essential facets of human existence, including water and energy resources, agricultural production, and the broader environmental systems. Method: The abstract primarily utilizes a descriptive approach to emphasize the impact of climate change on the Middle East, particularly the Arab region. It relies on a review of existing knowledge and data related to climate change and its effects on ecosystems and drought patterns. Results: The abstract outlines the direct and indirect repercussions of climate change on human life and the environment. It draws atten

... Show More
View Publication Preview PDF
Publication Date
Mon Mar 03 2025
Journal Name
Iop Conference Series: Earth And Environmental Science
Study on Frequency of Hard Tick Isolated from Goat (<i>Capra hircus</i> Linnaeus, 1758) in Iraq
...Show More Authors
Abstract<p>In Iraq, the domestic goat <italic>Capra hircus</italic> is valued as a valuable commercial resource. As obligatory ectoparasites, ixodid ticks cause significant harm to their animal hosts. Hard ticks parasitize the abdomen, inside limbs, ears, and head. Out of a total of 200 samples evaluated, 150 goat- infested samples had a total of 450 Hard ticks (303male and 147 female) and were infested at a rate of 75%. The results of the current research eight species of hard ticks were recognized. Goat species belonging to the family Ixodidae (Capra hircus: Linnaeus, 1758), obtained from distinct areas involving: the Iraqi capital Baghdad governorate [Al-Yusifiya], Al-Anbar governor</p> ... Show More
View Publication
Scopus Crossref
Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
EVALUATION OF ELECTRONIC GOVERNMENT SECURITY ISSUES APPLIED TO COMPUTER CENTER OF BAGHDAD UNIVERSITY (CASE STUDY)
...Show More Authors

Information security contributes directly to increase the level of trust between the government’s departments by providing an assurance of confidentiality, integrity, and availability of sensitive governmental information. Many threats that are caused mainly by malicious acts can shutdown the egovernment services. Therefore the governments are urged to implement security in e-government projects.
Some modifications were proposed to the security assessment multi-layer model (Sabri model) to be more comprehensive model and more convenient for the Iraqi government. The proposed model can be used as a tool to assess the level of security readiness of government departments, a checklist for the required security measures and as a commo

... Show More
View Publication Preview PDF