Moderate ultraviolet(UV)radiation from sunlight is essential for human health,but overexposure to UV rays can cause serious adverse *** is important to detect UV radiation from sunlight in time to prevent damage from ...
详细信息
Moderate ultraviolet(UV)radiation from sunlight is essential for human health,but overexposure to UV rays can cause serious adverse *** is important to detect UV radiation from sunlight in time to prevent damage from excessive ***,a ready-to-use,easy-to-interpret,inexpensive,reusable,and wearable all-in-one UV monitoring and shielding sensor SP-TPE@PU textile has been *** SP-TPE@PU textiles are constructed by photochromic molecule SP-TPE and commercial polymer polyurethane(PU)through *** SP-TPE molecule acts as the sensor component,and PU contributes to high *** SP-TPE@PU textiles show remarkable durability(against repeated twisting,curling,bending deformations,and water immersion)and good permeability,making them durable and breathable wearable *** exposed to sunlight,the SP-TPE@PU textiles rapidly exhibit significant color changes due to the efficient isomerization of SP-TPE,serving as an early warning and monitoring of UV *** addition,the SP-TPE@PU textiles can revert to the initial state with visible light irradiation for ***,the SP-TPE@PU textiles possess excellent UV shielding ability,contributing to human body *** and easy operation,significant and reversible color changes,good breathability and mechanical properties make SP-TPE@PU textiles reusable and wearable all-in-one UV monitoring and shielding sensors.
Biosignal representation learning (BRL) plays a crucial role in emotion recognition for game users (ERGU). Unsupervised BRL has garnered attention considering the difficulty in obtaining ground truth emotion labels fr...
详细信息
Biosignal representation learning (BRL) plays a crucial role in emotion recognition for game users (ERGU). Unsupervised BRL has garnered attention considering the difficulty in obtaining ground truth emotion labels from game users. However, unsupervised BRL in ERGU faces challenges, including overfitting caused by limited data and performance degradation due to unbalanced sample distributions. Faced with the above challenges, we propose a novel method of biosignal contrastive representation learning (BCRL) for ERGU, which not only serves as a unified representation learning approach applicable to various modalities of biosignals but also derives generalized biosignals representations suitable for different downstream tasks. Specifically, we solve the overfitting by introducing perturbations at the embedding layer based on the projected gradient descent (PGD) adversarial attacks and develop the sample balancing strategy (SBS) to mitigate the negative impact of the unbalanced sample on the performance. Further, we have conducted comprehensive validation experiments on the public dataset, yielding the following key observations: 1) BCRL outperforms all other methods, achieving average accuracies of 76.67%, 71.83%, and 63.58% in 1D-2C Valence, 1D-2C Arousal and 2D-4C Valence/Arousal, respectively;2) The ablation study shows that both the PGD module (+7.58% in accuracy on average) and the SBS module (+14.60% in accuracy on average) have a positive effect on the performance of different classifications;3) BCRL model exhibits the certain generalization ability across the different games, subjects and classifiers. IEEE
With the great development of Multi-Target Tracking(MTT)technologies,many MTT algorithms have been proposed with their own advantages and *** to the fact that requirements to MTT algorithms vary from the application s...
详细信息
With the great development of Multi-Target Tracking(MTT)technologies,many MTT algorithms have been proposed with their own advantages and *** to the fact that requirements to MTT algorithms vary from the application scenarios,performance evaluation is significant to select an appropriate MTT algorithm for the specific application *** this paper,we propose a performance evaluation method on the sets of trajectories with temporal dimension specifics to compare the estimated trajectories with the true *** proposed method evaluates the estimate results of an MTT algorithm in terms of tracking accuracy,continuity and ***,its computation is based on a multi-dimensional assignment problem,which is formulated as a computable form using linear *** enhance the influence of recent estimated states of the trajectories in the evaluation,an attention function is used to reweight the trajectory errors at different time ***,simulation results show that the proposed performance evaluation method is able to evaluate many aspects of the MTT *** evaluations are worthy for selecting suitable MTT algorithms in different application scenarios.
The advantages of Fe,Ni metals and one-dimensional(1D)carbon materials are combined in this study using a simple method to prepare FeNi/C nanofibers for electromagnetic microwave(EM)*** prepared FeNi/C nanofibers exhi...
详细信息
The advantages of Fe,Ni metals and one-dimensional(1D)carbon materials are combined in this study using a simple method to prepare FeNi/C nanofibers for electromagnetic microwave(EM)*** prepared FeNi/C nanofibers exhibit excellent EM absorption performance under dielectric/magnetic synergistic *** a frequency of 13.3 GHz,the minimum reflection loss(RLmin)reaches-57.15 dB,and effective absorption bandwidth(EAB)is as high as 4.0 GHz(12.5-16.5 GHz),with a thickness and filling rate of only 1.6 mm and 30 wt.%,*** shows that the EM absorption performance of FeNi/C nanofibers far exceeds that of single-component nanofibers and pure carbon fibers,and the excellent EM absorption performance is due to its unique microstructure and excellent electromagnetic *** FeNi alloy loaded on carbon nanofibers forms rich heterogeneous interfaces,and the three-dimensional(3D)conductive network composed of 1D carbon fibers increases the migration path of *** addition,FeNi alloy,as an impedance regulation factor,strengthens the dielectricity of the carbon matrix while providing multidimensional magnetism,achieving impedance *** work is thought to contribute to the promotion of emerging absorbers by providing a novel strategy for the development of new 1D magnetic carbon-based high-performance EM absorbing materials.
Grain boundary diffusion process(GBDP)has been developed as an effective approach to increase the coercivity of sintered Nd-Fe-B magnets by regulating the compositions and phase distributions near grain *** work aims ...
详细信息
Grain boundary diffusion process(GBDP)has been developed as an effective approach to increase the coercivity of sintered Nd-Fe-B magnets by regulating the compositions and phase distributions near grain *** work aims to explore how to select the optimum annealing temperature after *** this work GBDP was performed on a sintered Nd-Fe-B magnet using Dy_(70)Cu_(30) *** GBDP the low eutectic temperature of the grain boundary phases decreases from the initial 492 to 451℃.The magnetic property dependent on different annealing temperatures near the low eutectic temperature was *** magnetic properties,especially the squareness factor of demagnetization curve show a strong dependence on the annealing *** GBDP the optimal magnetic properties can be obtained after annealing just above the low eutectic temperature of the grain boundary *** mechanism is discussed based on the microstructure analysis.
Decentralized Anonymous Payment Systems (DAP), often known as cryptocurrencies, stand out as some of the most innovative and successful applications on the blockchain. These systems have garnered significant attention...
详细信息
For a sub-connected hybrid multiple-input multiple-output(MIMO) receiver with K subarrays and N antennas, there exists a challenging problem of how to rapidly remove phase ambiguity in only single time-slot. A directi...
详细信息
For a sub-connected hybrid multiple-input multiple-output(MIMO) receiver with K subarrays and N antennas, there exists a challenging problem of how to rapidly remove phase ambiguity in only single time-slot. A direction of arrival(DOA) estimator of maximizing received power(Max-RP) is proposed to find the maximum value of K-subarray output powers, where each subarray is in charge of one sector, and the center angle of the sector corresponding to the maximum output is the estimated true DOA. To make an enhancement on precision, Max-RP plus quadratic interpolation(Max-RP-QI) method is designed. In the proposed Max-RP-QI, a quadratic interpolation scheme is adopted to interpolate the three DOA values corresponding to the largest three receive powers of *** achieve the Cramer Rao lower bound, a Root-MUSIC plus Max-RP-QI scheme is developed. Simulation results show that the proposed three methods eliminate the phase ambiguity during one time-slot and also show low computational complexities. The proposed Root-MUSIC plus Max-RP-QI scheme can reach the Cramer Rao lower bound,and the proposed Max-RP and Max-RP-QI are still some performance losses 2–4 d B compared to the Cramer Rao lower bound.
The catalytic efficacy of copper-based catalysts for volatile organic compounds（VOCs） oxidation is significantly affected by the metal oxide support's chemical properties. However, rigorous comparative analyses ...
详细信息
The catalytic efficacy of copper-based catalysts for volatile organic compounds（VOCs） oxidation is significantly affected by the metal oxide support's chemical properties. However, rigorous comparative analyses on TiO2and CeO2supports are scarce. This study systematically constructs Cu/TiO2and Cu/CeO2catalysts and investigates their mechanisms in promoting propane oxidation. Cu/CeO2exhibits superior performance and stability. Our research reveals the key role of Cu-O-Ce interfacial architecture in forming Cu1+sites for efficient propane adsorption and triggering surface Olattgeneration, accelerating propane combustion. These findings elucidate Cu/CeO2catalyst enhanced performance and offer insights into non-noble metal catalysts. By demonstrating CeO2catalyst superiority, this study provides a basis for selecting optimal support materials to optimize catalyst performance, driving the development of cost-effective and eco-friendly catalytic technologies for air pollution control.
Traditional autonomous driving usually requires a large number of vehicles to upload data to a central server for training. However, collecting data from vehicles may violate personal privacy as road environmental inf...
详细信息
Moist-electric generation,a green and environmentally friendly energy harvesting technology,is undoubt-edly one of the effective methods to alleviate energy shortages and environmental ***,the lack of fiber-like moist...
详细信息
Moist-electric generation,a green and environmentally friendly energy harvesting technology,is undoubt-edly one of the effective methods to alleviate energy shortages and environmental ***,the lack of fiber-like moist-electric generators(MEGs)that combine continuous power generation and high electrical output performance has constrained the development of moist-electric in the fields of flexi-ble wearable and self-power *** this work,sodium alginate(SA)/multi-walled carbon nanotubes(MWCNT)fibers with axial heterogeneous(axi-he)of oxygen-containing functional groups(Ocfgs)are prepared through a mold forming method in assistance with the coagulation *** interaction be-tween axi-he MEG and moisture is investigated by analyzing the electrical signal changes of dried MEG under moisture *** maximum output voltage and current of axi-he MEG can reach 0.35 V and 1.92 pA under the stimulation of *** on the regulation of Ocfgs,axi-he MEG has a con-tinuous high moist-electric performance and environmental *** maximum output power density(Pmo)of axi-he MEG with a length of only 2 cm can reach 27.37 pW cm-2 at RH=90％,which exceeds most of the MEGs reported in ***,a continuous output voltage of 0.33-0.37 V for more than 15 h can be obtained from this axi-he ***,the axi-he MEG from Ocfg distribution design and mold forming method provides a new way of clean energy generation using moisture from the ambient environment,exhibiting enormous potential in energy supply for Internet of Things(loT)devices.
暂无评论