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The epistemic uncertainty in coronavirus disease (COVID-19) model-based predictions using complex noisy data greatly affects the accuracy of pandemic trend and state estimations. Quantifying the uncertainty of COVID-19 trends caused by different unobserved hidden variables is needed to evaluate the accuracy of the predictions for complex compartmental epidemiological models. A new approach for estimating the measurement noise covariance from real COVID-19 pandemic data has been presented based on the marginal likelihood (Bayesian evidence) for Bayesian model selection of the stochastic part of the Extended Kalman filter (EKF), with a sixth-order nonlinear epidemic model, known as the SEIQRD (Susceptible–Exposed–Infected–Quarantined–Recovered–Dead) compartmental model. This study presents a method for testing the noise covariance in cases of dependence or independence between the infected and death errors, to better understand their impact on the predictive accuracy and reliability of EKF statistical models. The proposed approach is able to reduce the error in the quantity of interest compared to the arbitrarily chosen values in the EKF estimation.

The efficiency of solar cells is strongly influenced by factors such as durability, cost-effectiveness, environmental compatibility, and overall performance. Recent advancements in kesterite-based CZTSSe solar cells have revealed a persistent challenge of low open-circuit voltage (V OC ), which significantly limits device efficiency. This work focuses on optimizing absorber and interface properties to enhance the simulated performance of CZTSSe solar cells. The thermal stability of the proposed structure is also evaluated by examining the effect of operating temperature on key photovoltaic parameters. To address performance limitations, a BaSi₂-based back surface field (BSF) layer is incorporated, and numerical simulations are carried out using the SCAPS-1D software. The introduction of the BaSi₂-based BSF layer effectively reduces V OC -related losses and enhances the overall device efficiency. The model’s validity is supported through comparison with previously published experimental and simulation data. Incorporating BaSi₂ as the BSF layer increases the simulated efficiency from 12.54% to 16.37%. In parallel, a systematic study of the CZTSSe absorber layer was conducted to determine the optimal thickness and doping concentration for further improving solar cell performance. The values can be varied systematically, such as the absorber’s layer thickness from 0.5 to 3 μm, and the doping concentration is modified from 10 12 to 10 18 cm − 3 . An efficiency of 19.61% can be achieved for the recently improved configuration using a CZTSSe thickness of just only 0.5 μm under idealized conditions but not experimentally realistic. This reduction of the thickness of the CZTSSe solar cells is an important factor in the decline of performance, but it can improve the lifetime of minority carriers.

The proposed research paper focuses on the study of fully depleted silicon (Si)‐on‐insulator negative capacitance metal oxide‐semiconductor field‐effect transistor (FDSOI‐NC‐MOSFET) performance for biosensor and digital circuit applications. The study mainly aims to use ferroelectric (FE) material to improve the performance and efficiency of FDSOI‐NC‐MOSFETs compared to conventional planar MOSFETs. Using TCAD software, the proposed device is simulated and analyzed under various parameter conditions (parameters like temperature, channel thickness, input supply voltages, and channel doping levels). Later, the proposed device is also designed for different biomolecular structures to analyze the selectivity and sensitivity behavior of the device. Sensitivity is the change in electrical characteristics in response to applied external stimuli or parameters like current and voltages. Variations in these parameters will affect the operating region of the device, thereby, the choice of parameters in achieving the best performance will depend on the operating conditions and device applications. NC‐MOSFET with FE materials can obtain an acceptable on/off current ratio by lowering the off current and can achieve an adequate subthreshold swing (SS), thus, observed that the NC‐MOSFET device has enhanced performance and transfer characteristics in comparison to planar MOSFET. For K = 4, at an input voltage of 0.25 V, the I on / I off ratio was 6.21 × 10 5 and the sensitivity was 6.20 × 10 7 and at 0.5 V, these values rise to 8.07 × 10 5 and 8.073 × 10 7 , respectively. Similarly for K = 6 and at an input voltage of 0.25 V, we observed an I on / I off ratio is 1.5 × 10 7 and a sensitivity of 1.52 × 10 9 . When the input voltage was increased to 0.5 V, the I on / I off ratio improved to 2.07 × 10 7 and the sensitivity increased to 2.073 × 10 9 . From these analyses, it is apparent that as the K ‐values increase at a given input voltage, both the I on / I off ratio and the sensitivity also increase significantly. Finally, in this paper, we also demonstrated the implementation and simulation of digital logic gates using the proposed NC‐MOSFET device, supporting circuit‐level design applications.

Cold Start problems in recommender systems pose various challenges in the adoption and use of recommender systems, especially for new item uptake and new user engagement. This restricts organizations to realize the business value of recommender systems as they have to incur marketing and operations costs to engage new users and promote new items. Owing to this, several studies have been done by recommender systems researchers to address the cold start problems. However, there has been very limited recent research done on collating these approaches and algorithms. To address this gap, the paper conducts a systematic literature review of various strategies and approaches proposed by researchers in the last decade, from January 2010 to December 2021, and synthesizes the same into two categories: data-driven strategies and approach-driven strategies. Furthermore, the approach-driven strategies are categorized into five main clusters based on deep learning, matrix factorization, hybrid approaches, or other novel approaches in collaborative filtering and content-based algorithms. The scope of this study is limited to a systematic literature review and it does not include an experimental study to benchmark and recommend the best approaches and their context of use in cold start scenarios.

In this fast-growing technological world biosensors become more substantial in human life and the extensive use of biosensors creates enormous research interest among researchers to define different approaches to detect biomolecules. The FET based biosensors have gained a lot of attention among all because of its high detection ability, low power, low cost, label-free detection of biomolecules, and CMOS compatible on-chip integration. The sensitivity of the biosensor inversely proportional to device size since they detect low concentration yields quick response time. Although FET based biosensor is having a lot of advantages among others but the short channel effects (SCE’s) and the theoretical limitation on the subthreshold swing (SS > 60mv/dec) of the FET leads to restrict device sensitivity and also have higher power dissipation due to the thermionic emission of electrons. To avoid these problems researchers focus shifts to the new technology FET based biosensors i.e. TFET based biosensors which are having low power and superior characteristics due to Band to band tunneling of carrier and steep subthreshold swing. This manuscript describes the full-fledged detail about the TFET based biosensors right from unfolding the device evaluation to biosensor application which includes qualitative and quantitative parameters analysis study like sensitivity parameters and different factors affecting the sensitivity by comparing different structures and the mechanisms involved. The manuscript also describes a brief review of different sensitivity parameters and improvement techniques. This manuscript will give researchers a brief idea for developing for the future generation TFET biosensors with better performance and ease of fabrication.

The work carried out in this paper first generates all edge-disjoint minimal paths between every pair of nodes of the interconnection network. Then the merging of the edge disjoint minimal paths from each source nodes to the rest of nodes occurs only if such merging of minimal paths does not result into cycle. Thus, the merging operation ensures connectivity of all nodes of interconnection network without any cycle which is equivalent to the generation of spanning trees. In this manner, a number of spanning tree rooted on each source node are generated and ranked according to their generation. The network reliability is then evaluated from these spanning trees by applying sum of disjoint product techniques on these trees. A mathematical model followed by an algorithm is proposed in this paper. The proposed method is well illustrated by taking a suitable example network. The simulated results obtained from the proposed method are validated against existing method. The validation results show a tolerable level discrepancy in estimating the network reliability of some benchmark networks while using a very less number of spanning trees in leu of all possible spanning tress. The network reliability of some important interconnection networks viz. Hypercube, crossed cube, folded hypercube, mesh and torus are evaluated and analyzed. The network reliability of fully connected network with size varying from 3 to 10 are evaluated and analysed.

This work investigated the performance of overlapped gate-on-drain of a gate all around-tunnel field-effect transistor (GAA-TFET) biosensors by considering the dielectric modulated technique by immobilizing the targeted biomolecules in the cavity region curved under the overlapped gate-on-drain. The nanowire GAA-TFET device shows excellent controllability over the channel and reduces leakage current to a greater extent. Here, we tried to make the ambipolar nature of the TFET, an advantage for the biosensor by detecting the biomolecule using variation of ambipolar current of TFET. Due to structural arrangement, the nanocavity under the overlapped gate region suppresses the ambipolar drain current by increasing the dielectric constant of the targeted biomolecules. The device can show a variation of 10 2 and 10 3 amount of sensitivity for the variation of dielectric constant from 1 to 5 and, compared with the other TFET structure, the proposed overlapped gate-on-drain GAA-TFET biosensor shows higher sensitivity and low leakage with a highly controlled channel.

The revolutions made in the CMOS technology are brought up by, continuous downscaling in order to obtain higher density, better performance and low power consumption, causing deleterious Short Channel Effects. Planar MOSFET’s have faced very hard challenges in the nanometer space, when ever the channel 4length happens to be in the same order of magnitude like the depletion-layer widths of drain and the source junctions. Hence, the channel length of the MOSFET’s should be great enough when compared to the sum of drain and source depletion widths in order to eradicate edge effects. Orelse numerous effects would occur. In MOSFET’s as channel Length diminishes the gate loose’s its control on the channel, as it isn’t good from power consumption point of view. MOSFET’s cannot control leakage path, removing leakage current is a path for improvising electrostatic control. A way of achieving it can be done by using a structure with multiple-gates as they allow the scaling of a transistor beyond the MOSFET scaling limit. In this case, the leakage current happens to be in the channel centre and reducing the channel decreases the current. Hence SOI and FINFET structures are used in order to achieve high gate-to-channel capacitance and decreases drain-to-channel capacitance. Another way of improvising the computational power can be done through changing the materials employed during manufacturing. In short, FINFET devices display superior SCE’s behaviour have considerably lower switching times, and higher current density than MOSFET technology. The review has been done on the various structures for performance escalation materials for FINFET structure performance Escalation as well as the various applications in which FINFET’s are used along with the various applications in which FINFET are used, various parameters used to perform RF and Linearity applications are noted.

In this paper, we present a double gate JL-TFET based biosensor by varying the gate dielectric constant to detect various biomolecules through label-free detection technique. An investigation regarding properties and behavior device has been investigated with the help of Silvaco TCAD. It is observed that Junction less TFET has advantageous over JLFET and TFETdue to the absence of junctions. The proposed device shows reduced short channel effects, lower subthreshold swing along with a higher voltage gain. The detection of the biomolecule is done by varying the gate dielectric constant inside the cavity and different electrical parameters such as electric field, sensing current, threshold voltage and transconductance are observed. The change in the threshold voltage, drain current, transconductance has been used as the sensing metric to detect the sensitivity of the presented device for biomolecule detection. Biomolecule position inside the cavity have been investigated to find out their effect on sensitivity parameter.

In this paper, a dielectric modulated dual material gate TFET (DM-DMG_TFET)based biosensor is proposed. In order to detect various biomolecules, a nanogap cavity is formed by the overlapping the gate on the drain side. The change in ambipolar current is considered as the sensing parameter by changing the dielectric constants of various immobilized biomolecule inside the nano cavity. A complete investigation on the performance of the biosensor is also done by considering different positions and filling factor of the biomolecules inside the nano cavity region. The dual-material gate structure is considered with dissimilar work functions (ф M1  < ф M2 ), which can effectively reduce the ambipolar current by enhancing the barrier width at channel-Drain junction. The proposed structure deliberately reduces ambipolar current and increases the sensitivity as compared to the single material gate structure. In this work we report a drift in the sensitivity from 10 4 to 10 6 for low dielectric constant biomolecules.