Multimode Slot-Waveguide Sensor Using TE/TM Polarizations for Enhanced Sensitivity
This study investigates the adoption of a different structure to serve as the platform for Multimode Interference sensing, the slot-waveguide. A Si\(_3\)N\(_4\) slot-waveguide on a SiO\(_2\) substrate is numerically modeled, and a demonstration is presented on how the low-index guiding mechanism allied with a careful selection of the propagating modes can be used for sensitivity enhancement. Optimized devices presented bulk sensitivities per sensor length up to 3.43 rad\(\cdot \) RIU\(^{-1} \cdot \)\(\mu \)m\(^{-1}\) (for 633 nm wavelength of operation), that when compared to the highest sensitivity MMI sensors in the lite...
Source: Sensing and Imaging - June 30, 2023 Category: Biomedical Engineering Source Type: research
An Attention-Based Swin U-Net-Based Segmentation and Hybrid Deep Learning Based Diabetic Retinopathy Classification Framework Using Fundus Images
This study employs an attention-based deep learning framework for classifying DR using fundus images, and the severity level is estimated to provide better treatment. The required fundus images are obtained through real-world benchmark datasets. Then, the attained images are pre-processed to remove unnecessary distortions in the images. Subsequently, the resultant pre-processed image is sent through the attention-based swin U-net for segmentation, where the affected diseased part is clearly visualized using the segmentation process. Here, the hybrid optimization algorithm named spiral bacterial colony optimization (SBCO) i...
Source: Sensing and Imaging - June 24, 2023 Category: Biomedical Engineering Source Type: research
Forgery Detection of Digital Images Using Teaching –Learning Based Optimization and Principal Component Analysis
AbstractPresent day image processing tools enable the user to modify the contents of digital images for improving the quality, colour balance, appearance, and so on. They can also be used for creating false evidence for insurance claim, law of court, medical diagnosis and treatment, thereby requiring authentication before using digital images as evidences. The interest point based forgery detection techniques are well-accepted as they are computationally better than block based approaches, still they fail to detect when the forged region is smooth with low gradients. This paper endeavours to use a limited number of interes...
Source: Sensing and Imaging - June 14, 2023 Category: Biomedical Engineering Source Type: research
Requirements for the Coding Matrix of a Probing Signal with Zero Autocorrelation Zone for the Remote Sensing Radar
AbstractOptimal discrete signals does not allow solving the problem of radar range resolution for echo signals overlapping in time with significantly different amplitudes. Also, these signals limit the possibility of improving the quality of the radar image in radar equipment of different applications due correlation noise. Therefore, to solve the above problem, it is of interest to use a probing signal with a zero autocorrelation zone. To form an autocorrelation function with a zero sidelobes region, a probing signal must be a pulse train of two or more phase-code shift keyed pulses. It is analytically substantiated in th...
Source: Sensing and Imaging - June 12, 2023 Category: Biomedical Engineering Source Type: research
A Novel Faster RCNN Model Based on Multi-scale Feature Fusion and Shape Priori for Dense Vehicle Detection
AbstractCompared with conventional targets, dense targets have less information, and the training data is difficult to be labeled, which leads to the poor detection effect with general target detection methods on dense targets, while the detection methods specially designed for dense targets are often too complex or not universal. To solve the above problems, this paper proposes a novel faster RCNN model based on multi-scale feature fusion and shape priori for dense vehicle detection. This proposed dense vehicle detection model is divided three steps. Firstly, the training strategy of multi-scale network captures the lost ...
Source: Sensing and Imaging - June 9, 2023 Category: Biomedical Engineering Source Type: research
Multiplexed Hybrid Plasmonic Ring Resonator Sensor for Label Free Biosensing Applications
AbstractLabel free multiplexed gold coated ring resonator refractive index sensor is designed which can detect cancer cells, different glucose and hemoglobin concentrations simultaneously. Various parameters of the ring resonator such as radius, gap between ring and straight waveguide, coupling length and thickness of gold layer are optimized to achieve high sensitivity of 424 nm/RIU and Q factor of 802. The proposed multiplexed hybrid ring resonator sensor has the potential for miniature size ultracompact sensing applications. (Source: Sensing and Imaging)
Source: Sensing and Imaging - May 31, 2023 Category: Biomedical Engineering Source Type: research
Perfect Absorber Based on Epsilon-Near-Zero Metamaterial as a Refractive Index Sensor
AbstractWe have designed a multilayer metamaterial structure which exploits the epsilon-near-zero (ENZ) mode for perfect absorption. The design procedure is based on the effective medium theory (EMT) model. The proposed multilayer structure consists of layers of Ag, InSb, SiO2. The thickness of the layers is adjusted so that the ENZ mode is at the communication wavelength of 1550 nm. Two alternations of the layered structure are placed on a metal (Ag) substrate to prevent light transmission. Placing the nano-ring cavity arrays at the top of the multilayer structure leads to excitation of the surface plasmon polaritons (S...
Source: Sensing and Imaging - May 22, 2023 Category: Biomedical Engineering Source Type: research
CTA-FPN: Channel-Target Attention Feature Pyramid Network for Prohibited Object Detection in X-ray Images
AbstractFast and accurate prohibited object detection in X-ray images is great challenging. Based on YOLOv6 object detection framework, in this paper, Channel-Target Attention Feature Pyramid Network (CTA-FPN) is proposed for prohibited object detection in X-ray images. It includes two key components: TAAM (Target Aware Attention Module) and CAM (Channel Attention Module). TAAM is to generate the target attention map to enhance the features of prohibited object regions and suppress those of the background regions, so as to solve the problems of object occlusion and cluttered background in X-ray images. CAM is to highlight ...
Source: Sensing and Imaging - May 4, 2023 Category: Biomedical Engineering Source Type: research
Automatic and Non-iteration Algorithm for Compensating the Phase Error for SAR based on the PGA Algorithm
AbstractAlthough many improvements have been made to synthetic aperture radar navigation systems ؛ However, it is still not possible to eliminate all the phase errors caused by the unintentional movement of the platform with these systems. Therefore, automatic phase correction algorithms were invented, the most widely used of which is the Phase Gradient Autofocus algorithm that called PGA. Th is algorithm has some drawbacks despite its good performance. The most important of these is the iterative of this algorithm, which requires high computational time. In addition, the uncertainty in the optimality of the output answe...
Source: Sensing and Imaging - April 21, 2023 Category: Biomedical Engineering Source Type: research
A Sparsity Reconstruction Algorithm of Electromagnetic Tomography Technique for High Conductivity Medium Imaging
AbstractElectromagnetic tomography (EMT) is a versatile tomographic imaging technique for reconstruction of conductivity and/or permeability distribution due to the advantages of non-contact, non-intrusive, low-cost, simple structure and fast imaging. However, the ill-posed and ill-conditioned features of EMT make it difficult to obtain high quality reconstructed images. To improve the spatial resolution of the high conductivity medium imaging, theL1–L1 framework objective function is presented, which usesL1 norm as both the data fidelity term and the regularization term to weaken the influence of the data outliers and i...
Source: Sensing and Imaging - April 12, 2023 Category: Biomedical Engineering Source Type: research
Lung Nodule Detection via Optimized Convolutional Neural Network: Impact of Improved Moth Flame Algorithm
AbstractLung cancer is a high-risk disease that affects people all over the world, and lung nodules are the most common sign of early lung cancer. Since early identification of lung cancer can considerably improve a lung scanner patient's chances of survival, an accurate and efficient nodule detection system can be essential. Automatic lung nodule recognition decreases radiologists' effort, as well as the risk of misdia gnosis and missed diagnoses. Hence, this article developed a new lung nodule detection model with four stages like “Image pre-processing, segmentation, feature extraction and classification”. In this ...
Source: Sensing and Imaging - March 13, 2023 Category: Biomedical Engineering Source Type: research
A Review of Quartz Crystal Microbalance for Chemical and Biological Sensing Applications
We present various high-sensitivity coating techniques that use this novel sensor design. Then, we briefly review available measurement parameters and technological interventions that will inform future QCM researc h. Lastly, we examine QCM’s theory and application to enhance our understanding of relevant electrical components and concepts. (Source: Sensing and Imaging)
Source: Sensing and Imaging - March 4, 2023 Category: Biomedical Engineering Source Type: research
A Hybrid Method for the Removal of RVIN Using Self Organizing Migration with Adaptive Dual Threshold Median Filter
AbstractDay-by-day impulse detection seems critical because removing the random-valued impulse noise with high density from the noisy image is a typical task. The specified noise does not regularly obstruct the pixels of the image. The proposed work, which combines self-organizing migration& adaptive dual-threshold techniques, gives optimal output for the noisy image in less time. The proposed methodology has been applied on various noisy images with different window sizes and it has proven better results while reconstructing the original image with high quality from the noisy image. To evaluate the performance of the ...
Source: Sensing and Imaging - February 27, 2023 Category: Biomedical Engineering Source Type: research
A Simple and Feasible Detection of Pipe/Tank-Wall Thinning and Corrosion Using Piezoceramic Transducers
AbstractIt is well known that corrosion drastically shortens the lifespan of pipelines. Pipe wall thinning and leakage due to corrosion are important safety concerns for pipes used in oil, petrochemical, and power plant industries. Cross-sectional irregularity, such as eccentricity or local wall thinning, which normally develops due to either process restrictions or extensive usage, is a prevalent problem in such plants. This paper introduces the feasibility of detecting pipelines and tanks thinning damage using piezo-ceramic transducers (PZCs) resonating at 2 MHz. Time and frequency processing were used in combination w...
Source: Sensing and Imaging - February 27, 2023 Category: Biomedical Engineering Source Type: research
Indoor Air Sensing: A Study in Cost, Energy, Reliability and Fidelity in Sensing
AbstractThe rise in environmental pollution and degradation of air quality worldwide has dragged researchers ’ attention due to its direct societal impact. Studies reveal that the indoor environment is more polluted than the outdoors. In this paper, a framework for indoor air quality monitoring has been presented. We have developed a portable and cost-effective air quality monitoring device. The device g enerates fine-grained data for a combination of different pollutants and meteorological sensors (humidity and temperature). In this work, an energy-aware Environment Monitoring Device (EMD) has been developed with an ada...
Source: Sensing and Imaging - February 20, 2023 Category: Biomedical Engineering Source Type: research
