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.
Document source identification in printer forensics involves determining the origin of a printed document based on characteristics such as the printer model, serial number, defects, or unique printing artifacts. This process is crucial in forensic investigations, particularly in cases involving counterfeit documents or unauthorized printing. However, consistent pattern identification across various printer types remains challenging, especially when efforts are made to alter printer-generated artifacts. Machine learning models are often used in these tasks, but selecting discriminative features while minimizing noise is essential. Traditional KNN classifiers require a careful selection of distance metrics to capture relevant printing
... Show MoreRG Majeed, AS Ahmed, Jornal of Al-Muthanna for Agricultural Sciences, 2023
Strives Total Productive Maintenance to increase the overall effectiveness of the equipment through the early involvement in the design and manufacture of equipment productivity. It also operates in an environment of simultaneous engineering work on the synchronization of activities to take advantage of early information by maintenance engineers, design, operation, and that helps to reduce the faults and facilitate future maintenance tasks.
Has adopted a search in the theoretical concept of the total maintenance productivity and concurrent engineering activities carried out during which the conjunction a
... Show MoreMotivation is one of the most important factors that influence students learning and has a great effect on their success and achievement. For this reason, in this paper, the researcher is going to investigate the motivational teaching strategies used by EFL Iraqi school teachers. To achieve the aim of the study, the researcher adapted a questionnaire with some changes and modification’s. This questionnaire with five point scale (always, often, sometimes, rarely and never). To achieve face validity, the questionnaire items are given to a jury of experts. Alpha Cronbach formula is used to achieve the questionnaire reliability. After that, the questionnaire was applied on a sample of 38 teachers during the academic year 2019-2020. Th
... Show MoreThe study aims at:
1- Identifying the contemporary educational approaches in teaching arts.
2- The effectiveness of using the visual thinking strategy in photography subject for the first year students in the institute of fine arts/Holy city of Kadhimiyah.
The study sample is made of (30 ) first year students (in the institute of fine arts/in Holy city of Kadhimiyah) distributed into two groups, an experimental group made of (15) students and a control group having the same number of students in order to conduct the test. The test for the visual thinking strategy in the subject of photography has been designed and the validity and reliability for the research tool have been verified. In order to demonstrate the results of the