Increasing Solar Energy Conversion Efficiency in Thin Film Hydrogenated Amorphous Silicon Solar Cells with Patterned Plasmonic Silver Nano-Disk Array

Thin film hydrogenated amorphous silicon (a-Si:H) solar photovoltaic (PV) cells are inexpensive and have the fastest energy payback time, however, they suffer from light-induced degradation in performance termed as the Staebler-Wronski effect (SWE). Recent advances in the field of plasmonics have revealed the ability of metallic nanostructures to provide polarization independent, wide angle and broadband absorption for ultrathin active absorbing layers (\u3c100 \u3enm). We investigated a two-dimensional array of multi-resonant plasmonic nano-disk structures to improve the optical absorption in the active absorbing layer of a-Si:H PV cells and to compensate for the negative effects of SWE. This nano-disk patterned solar cell (NDPSC) was found to be superior in performance over a commercial thin film a-Si:H reference PV cell by 18.51% for total optical absorption and by 19.65% in short-circuit current density (JSC). To maximize the optical enhancement in the NDPSC structures, ultra-thin transparent conducting oxide (TCOs) films with high transmittance and low resistivity are desired. We theoretically investigated the ultra-thin (\u3c 50nm) TCO films of different materials and thickness to ascertain their potential employment in plasmonic-enhanced a-Si:H PV devices. We further numerically evaluated the performance of NDPSC structures for experimentally optimized (by our collaborators) ultra-thin TCO films of indium tin oxide (ITO) having high transmittance and low resistivity. We found a 21% enhancement in optical absorption in the active layer of NDPSC structures using a 36nm high quality ITO films. The plasmonic nanostructures employed for improving optical absorption in solar PV cell applications are not lossless, and suffer from Ohmic losses. We developed a novel technique of exchanging undesired Ohmic losses in metals with useful absorption in the active semiconducting layers in plasmonic-enhanced PV cells. This technique requires the tailoring of geometric skin depth of metals and engaging the inherent absorbance characteristics of the semiconductors. We have demonstrated that between 75%-95% absorbance can be achieved in the semiconducting layers using this technique

Open electronics for medical devices: State-of-art and unique advantages

A wide range of medical devices have significant electronic components. Compared to open-source medical software, open (and open-source) electronic hardware has been less published in peer-reviewed literature. In this review, we explore the developments, significance, and advantages of using open platform electronic hardware for medical devices. Open hardware electronics platforms offer not just shorter development times, reduced costs, and customization; they also offer a key potential advantage which current commercial medical devices lack—seamless data sharing for machine learning and artificial intelligence. We explore how various electronic platforms such as microcontrollers, single board computers, field programmable gate arrays, development boards, and integrated circuits have been used by researchers to design medical devices. Researchers interested in designing low cost, customizable, and innovative medical devices can find references to various easily available electronic components as well as design methodologies to integrate those components for a successful design

Efficacy of Decentralized CSS Clustering Model Over TWDP Fading Scenario

Cognitive Radio technology, which lowers spectrum scarcity, is a rapidly growing wireless communication technology. CR technology detects spectrum holes or unlicensed spectrums which primary users are not using and assigns it to secondary users. The dependability of the spectrum-sensing approach is significantly impacted from two of the most critical aspects, namely fading channels and neighboring wireless users. Users of non-cooperative spectrum sensing devices face numerous difficulties, including multipath fading, masked terminals, and shadowing. This problem can be solved using a cooperative- spectrum-sensing technique. For the user, CSS enables them to detect the spectrum by using a common receiver. It has also been divided into distributed CSS and centralized CSS. This article compares both ideas by using a set of rules to find out whether a licensed user exists or not. This thought was previously used to the conventional fading channels, such as the Rician, Rayleigh and the nakagami-m models. This work focused on D-CSS using clustering approach over TWDP fading channel using two-phase hard decision algorithms with the help of OR rule as well as AND rule. The evaluation of the proposed approaches clearly depicted that the sack of achieve a detection-probability of greater than 0.8; the values SNR varies between -14 dB to -8 dB. For all two-phase hard decision algorithms using proposed approach and CSS techniques, the detection probability is essentially identical while the value of signal to noise ratio is between -12 dB to -8dB. Throughout this work, we assess performance of cluster-based cooperative spectrum-sensing over TWDP channel with the previous findings of AWGN, Rayleigh, and wei-bull fading channels. The obtained simulation results show that OR-AND decision scheme enhanced the performance of the detector for the considered range of signal to noise ratios

INKJET PRINTING MATERIALS

An inkjet printing material comprises a mixture that includes a solvent and a crosslinkable organic material dispersed in the solvent, and an additive configured to modify a surface tension of the mixture. The additive includes a low surface tension surfactant, such as a siloxane based polymer or oligomer (e.g., polyether siloxanes or polyester siloxanes, such as polyether modified polydimethylsiloxane or polyether modified dimethylpolysiloxane), a fluorinated based polymer, oligomer, or small molecule surfactant, fluorinate siloxane, or a combination thereof. In some embodiments, a weight percentage of the additive is between about 0.1% and about 5% (e.g., between about 0.3% and about 1%) of the solid materials in the inkjet printing material

Optimal Design of Thin-film Plasmonic Solar Cells using Differential Evolution Optimization Algorithms

International audienceAn approach using a differential evolution (DE) optimization algorithm is proposed to optimize design parameters for improving the optical absorption efficiency of plasmonic solar cells (PSC). This approach is based on formulating the parameters extraction as a search and optimization process in order to maximize the optical absorption in the PSC. Determining the physical parameters of three-dimensional (3-D) PSC is critical for designing and estimating their performance, however, due to the complex design of the PSC, parameters extraction is time and calculation intensive. In this paper, this technique is demonstrated for the case of commercial thin-film hydrogenated amorphous silicon (a-Si:H) solar photovoltaic cells enhanced through patterned silver nano-disk plasmonic structures. The DE optimization of PSC structures was performed to execute a real-time parameter search and optimization. The predicted optical enhancement (OE) in optical absorption in the active layer of the PSC for AM-1.5 solar spectrum was found to be over 19.45% higher compared to the reference cells. The proposed technique offers higher accuracy and automates the tuning of control parameters of PSC in a time-efficient manner

View Consistent Purification for Accurate Cross-View Localization

This paper proposes a fine-grained self-localization method for outdoor robotics that utilizes a flexible number of onboard cameras and readily accessible satellite images. The proposed method addresses limitations in existing cross-view localization methods that struggle to handle noise sources such as moving objects and seasonal variations. It is the first sparse visual-only method that enhances perception in dynamic environments by detecting view-consistent key points and their corresponding deep features from ground and satellite views, while removing off-the-ground objects and establishing homography transformation between the two views. Moreover, the proposed method incorporates a spatial embedding approach that leverages camera intrinsic and extrinsic information to reduce the ambiguity of purely visual matching, leading to improved feature matching and overall pose estimation accuracy. The method exhibits strong generalization and is robust to environmental changes, requiring only geo-poses as ground truth. Extensive experiments on the KITTI and Ford Multi-AV Seasonal datasets demonstrate that our proposed method outperforms existing state-of-the-art methods, achieving median spatial accuracy errors below $0.5$ meters along the lateral and longitudinal directions, and a median orientation accuracy error below 2 degrees.Comment: Accepted for ICCV 202