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PublicationPerformance analysis of diabetic retinopathy detection using fuzzy entropy multi-level thresholding(Elsevier Ltd, 2023)Diabetic Retinopathy (DR) is one of the major causes of blindness. Many DR detection systems were developed to segment and determine the type and number of lesions that appeared on retinal images and used to classify DR and its severity level. Even though several researchers have already proposed many automated diagnosis systems with different image segmentation algorithms, their accuracy and reliability are generally unexplored. The accuracy of an automated diagnosis system usually depends on the segmentation techniques. The accuracy of this system is heavily dependent upon the retinal and image parameters, which have intensity level difference between background (BG)-blood vessels (BV), BV-bright lesions, BV-dark lesions, and noise levels. In this work, the automated diagnosis system accuracy has been analysed to successfully detect DR and its severity levels. The focus is on fundus image modalities segmentation based on fuzzy entropy multi-level thresholding. The analysis aimed to develop conditions to guarantee accurate DR detection and its severity level. Firstly, a retinal image model was developed that represents the retina under the variation of all retinal and image parameters. Overall, 45,000 images were developed using the retinal model. Secondly, feasibility and consistency analysis were performed based on a specific design Monte Carlo statistical method to quantify the successful detection of DR and its severity levels. The conditions to guarantee accurate DR detections are: BG to BV > 30% and BV to the dark lesions (MAs) >15% for mild DR, BG to BV > 40% and BV to the dark lesions (MAs and HEM) > 20% for moderate DR, and BG to BV > 30% and BV to the dark lesions (MAs and HEM) > 15%, and BV to the bright lesions (EX) > 55% for severe DR. Finally, the validity of these conditions was verified by comparing their accuracy against real retinal images from publicly available datasets. The verification results demonstrated that the condition for the analysis could be used to predict the success of DR detection.
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PublicationPerformance investigations on integrated MMF/FSO transmission enabled by OAM beams(Elsevier B.V., 2023)This paper introduces a new hybrid system for high-bandwidth and high-transmission-capacity communication. The system integrates a multi-mode fiber (MMF) cable with free space optics (FSO) using orbital angular momentum (OAM) multiplexing. The proposed system uses a single wavelength to simultaneously transmit 40 Gb/s data on four distinct OAM beams ((LG0,0, LG0,17, LG0,40, and LG0,75)) with a symmetric circular shape. The performance of the system was evaluated with a fixed MMF length of 100 m and varying FSO ranges, according to extreme climate changes such as rain and fog, and atmospheric turbulences. The results indicate that the suggested system is capable of transmit up to 1250 m (100 m MMF length + 1150 m FSO range) under clear weather (CW) and weak turbulence (WT), with a minimum transmission distance of 440 m (100 m MMF length + 340 m FSO range) under heavy fog (HF). The performance of the system was also demonstrated based on actual meteorological data for two different cities, Alexandria, Egypt and Chandigarh, India, with different visibility ranges and geographical locations. Since Alexandria has a longer visibility range than Chandigarh, our proposed model could spread over a larger area than it could be in Chandigarh. The obtained ranges were within an acceptable bit error rate (BER) of less than 10−9. The system's maximum range was 1200 m for Alexandria and 1100 m for Chandigarh. The proposed model can be suggested for use in next generation (NG) passive optical networks (PON) for supporting symmetric 40 Gb/s data.
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PublicationUHF RFID tag antennas for wearable devices(AIP Publishing Ltd., 2023)RFID technology is evolving as one of the most popular technologies in this era of technology, fast gaining attention due to high demand from users and rapidly garnering interest in scientific and commercial areas. The frequency used will be determined by the RFID application, and the power rate will change as the frequency increases. Without a straight line of sight, the RFID tag antenna can identify distinct objects. For wearable applications, several RFID tag antennas are too big to match the chip impedance. In order to overcome that problem, a small tag RFID tag antenna for UHF is designed which aimed to be operated from 865 to 867 MHz for assembling production. Impedance matching is used to transforms the impedance of the radiating antenna, to match the chip impedance. To design and simulate the designed antenna, CST Microwave Studio software has been used in this project to get the desired result which is the return loss and gain. The design for this antenna is very simple to ease the fabrication process. Overall, the construction comprises a spiral-shaped loop RFID tag antenna printed on Roger substrate RO4350 with a height of 0.8 mm and a dielectric constant of 3.3. The simulation result of the reflection coefficient of the antenna is 866 MHz at the operating frequency.
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PublicationHRV stress analysis using k-NN clustering technique(AIP Publishing Ltd., 2023)Human life in the modern scenario has become quite taxing; mental health issues are on the rise. Our medical science may have progressed well enough to furnish physical health excellency in the general populace (of course, in relative terms), but mental health is still taboo. This is especially so in many of the non-first-world countries, where forthcoming mental health issues and asking for help can lead to anything from public ridicule to social ostracism. In such a scenario, it is of paramount importance that someone comes up with a more private approach to mental health care and well-being. In this paper, the authors discuss how the effects of stress can be monitored using a different implementation of k-NN (k-Nearest Neighbors). With this, using the Manhattan distance metric we were able to achieve 99.84% accuracy, and even after the application of PCA, we achieved 93.97% accuracy. © 2023 American Institute of Physics Inc.. All rights reserved.
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PublicationA multilayers adaptive ALACO-OFDM for spectral efficiency improvement using PSO algorithm in visible light communication systems(De Gruyter, 2023)In this paper, we propose a new adaptive layered asymmetrically-clipped optical orthogonal frequency division multiplexing (ALACO-OFDM) technique as a method to improve the spectral efficiency of optical system, especially visible light communication (VLC). Particle swarm optimisation (PSO)-based LACO-OFDM method is used for this purpose and the channel capacities are studied. Simulations using variable layers are carried out to validate the theoretical steps. The simulation results indicate that the ALACO-OFDM technique has significantly improve the spectral efficiency compared to previous techniques such as ACO-OFDM. Moreover, it is shown that channel capacities of different layers are significantly improved when electrical power is increased.