Accurate identification of impact loads is vital for structural assessment and design. Traditional methods rely on complex equipment, such as accelerometers or strain gauge, which can be expensive and prone to failure...
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Accurate identification of impact loads is vital for structural assessment and design. Traditional methods rely on complex equipment, such as accelerometers or strain gauge, which can be expensive and prone to failure. This study introduces a non-contact intelligent identification approach incorporating visual sensing technology, providing a convenient means to identify impact loads. Numerical simulations explore the differences in identifying impact forces through acceleration and displacement responses, particularly by considering such variables as measurement noise and number of measurement points. A meticulously designed experiment verified the feasibility of the proposed method for measuring the displacement and velocity of rapidly moving targets, and evaluated its performance in terms of accuracy. A series of impact loading experiments were conducted on a simply supported girder bridge model to validate the effectiveness of the proposed impact force identification method. Results indicate strong agreement between displacement response measurements and percentile meters. The proposed non-contact method accurately identifies single or continuous impact loads, with a minimum peak relative error of 0.2%. This study represents a pioneering application of intelligent visual sensing technology in the field of impact load identification. Moreover, the current research introduces a novel approach to address the challenges faced by conventional methods in identifying impact loads. Future research can leverage the groundwork laid by this study to further optimize and expand the proposed method, enhancing its capabilities and fully harnessing its potential to offer advanced solutions in structural health monitoring.
Polydimethylsiloxane(PDMS)is an electron-withdrawing material that is widely used in triboelectric nanogenerators(TENGs).However,PDMS has poor mechanical properties after curing and is easily damaged when subjected to...
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Polydimethylsiloxane(PDMS)is an electron-withdrawing material that is widely used in triboelectric nanogenerators(TENGs).However,PDMS has poor mechanical properties after curing and is easily damaged when subjected to long-term ***,the long-term stable operation of TENGs under mechanical deformation cannot be *** this work,multiple hydrogen bonds and aromatic disulfide bonds were introduced into PDMS *** elastomers exhibited high toughness(a tensile strength of 1.91 MPa and an elongation at break of 340%),good recyclability,and room-temperature self-healing properties(healing efficiency of 96.4%in 24 h).Recyclable sandwich-like triboelectric nanogenerators with excellent electrical output performance(13.5 V)and room-temperature self-healing performance(24 h,98%recovery of self-generating performance)were prepared by utilizing the hydrogen bonding between the PDMS elastomer and *** work reported herein offers theoretical guidance and a compelling strategy for developing high-performance TENG negative friction layers.
Salinity is a major challenge for plant growth, but Populus euphratica, a species native to desert regions, has a remarkable ability to tolerate salt stress. This study aimed to explore how salinity affects the rhizos...
Salinity is a major challenge for plant growth, but Populus euphratica, a species native to desert regions, has a remarkable ability to tolerate salt stress. This study aimed to explore how salinity affects the rhizosphere microbiome of P. euphratica, focusing on diversity patterns, assembly mechanisms, network characterization, and the functional roles of specialists and generalists under salt stress conditions. The findings revealed that increased salinity enhances the complexity of the rhizosphere microbial network and the diversity of bacterial specialists. Specialists demonstrated a wider range of environmental adaptation and played a pivotal role in species interactions within the microbial network. Notably, salinity stress altered the structure and assembly of plant rhizosphere specialists, facilitating functional compensation and potentially augmenting the health of P. euphratica. This research offers critical insights into the microbiome dynamics of P. euphratica under salinity stress, advancing the understanding of specialists and generalists in the rhizosphere.
Seeking new energy sources, especially those with less environmental impact, has been a consistent effort in the field of energy harvesting. In this work, we present an innovative energy harvesting technique for colle...
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Seeking new energy sources, especially those with less environmental impact, has been a consistent effort in the field of energy harvesting. In this work, we present an innovative energy harvesting technique for collecting energy from clothing. In this convenient but powerful method, electrical energy is generated by simply sliding a zein film assembly on the surface of clothes by constructing zein/cloth direct current (DC) triboelectric nanogenerators (TENGs). These TENGs contain only one electrode, which is connected to the zein assembly, leaving the cloth electrode free. Therefore, the clothes avoid any modification or tailoring, allowing for typical washing after separating the zein. Upon testing many ordinary clothing made with typical fabrics, the proposed zein/cloth TENGs worked efficiently with the most studied fabrics. The zein/cloth DC TENGs could generate electrical signals with an output performance of V = 23.45 V and I = 113.12 nA, making it capable of easily powering at least 10 LED lights simultaneously. Thus, our pioneer work provides a promising method for designing a portable ultra-light nano-energy generator that can harvest energy for small electrical power demands using the simple friction between clothes and the flexible zein assembly, irrespective of the location and time. This technique damages the clothing only negligibly and extricates energy harvesting from environmental constraints, such as sunlight and wind.
A dynamic multi-beam resource allocation algorithm for large low Earth orbit(LEO)constellation based on on-board distributed computing is proposed in this *** allocation is a combinatorial optimization process under a...
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A dynamic multi-beam resource allocation algorithm for large low Earth orbit(LEO)constellation based on on-board distributed computing is proposed in this *** allocation is a combinatorial optimization process under a series of complex constraints,which is important for enhancing the matching between resources and requirements.A complex algorithm is not available because that the LEO on-board resources is *** proposed genetic algorithm(GA)based on two-dimen-sional individual model and uncorrelated single paternal inheri-tance method is designed to support distributed computation to enhance the feasibility of on-board application.A distributed system composed of eight embedded devices is built to verify the algorithm.A typical scenario is built in the system to evalu-ate the resource allocation process,algorithm mathematical model,trigger strategy,and distributed computation *** to the simulation and measurement results,the proposed algorithm can provide an allocation result for more than 1500 tasks in 14 s and the success rate is more than 91%in a typical *** response time is decreased by 40%com-pared with the conditional GA.
Ionic liquid electrospray(ILE) in an atmospheric environment is often accompanied by the gas discharge phenomenon. It interferes with the normal operation of the electrospray and the measurement of experimental parame...
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Ionic liquid electrospray(ILE) in an atmospheric environment is often accompanied by the gas discharge phenomenon. It interferes with the normal operation of the electrospray and the measurement of experimental parameters. In this study, electrospray experiments were conducted on the ionic liquid EMI-BF4. The observations revealed that the operating modes of the ionic liquid depend on the voltage polarity at high voltages. Additionally, a correspondence between the operating mode of ILE and the current signal in the circuit was established. The shape of the liquid cone formed at the needle tip bore a striking resemblance to the plume of corona discharge, suggesting that the motion trajectory of electrons influenced the curvature of the liquid cone. Steamer theory provided a clear explanation for the change in curvature as the voltage increased.
In this paper,a hybrid integrated broadband Doherty power amplifier(DPA)based on a multi-chip module(MCM),whose active devices are fabricated using the gallium nitride(GaN)process and whose passive circuits are fabric...
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In this paper,a hybrid integrated broadband Doherty power amplifier(DPA)based on a multi-chip module(MCM),whose active devices are fabricated using the gallium nitride(GaN)process and whose passive circuits are fabricated using the gallium arsenide(GaAs)integrated passive device(IPD)process,is proposed for 5G massive multiple-input multiple-output(MIMO)*** inverted DPA structure with a low-Q output network is proposed to achieve better bandwidth performance,and a single-driver architecture is adopted for a chip with high gain and small *** proposed DPA has a bandwidth of 4.4-5.0 GHz that can achieve a saturation of more than 45.0 *** gain compression from 37 dBm to saturation power is less than 4 dB,and the average power-added efficiency(PAE)is 36.3%with an 8.5 dB peak-to-average power ratio(PAPR)in 4.5-5.0 *** measured adjacent channel power ratio(ACPR)is better than50 dBc after digital predistortion(DPD),exhibiting satisfactory linearity.
Fragmented data suggest that bisphenol AF(BPAF),a chemical widely used in a variety of products,might have potential impacts on the ***,we employed male neonatal mice following maternal exposure to explore the effects...
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Fragmented data suggest that bisphenol AF(BPAF),a chemical widely used in a variety of products,might have potential impacts on the ***,we employed male neonatal mice following maternal exposure to explore the effects of low-dose BPAF on hypothalamic development by *** found that maternal exposure to approximately 50μg/(kg·day)BPAF from postanal day(PND)0 to PND 15 altered the hypothalamic transcriptome,primarily involving the pathways and genes associated with extracellular matrix(ECM)and intercellular adhesion,neuroendocrine regulation,and neurological *** RNA analysis confirmed the changes in the expression levels of concerned ***,we further revealed that low-dose BPAF posed a stimulatory impact on pro-opiomelanocortin(POMC)neurons in the arcuate nucleus of the hypothalamus and induced the browning of inguinal white adipose *** findings indicate that developmental exposure to low-dose BPAF could interfere with hypothalamic development and thereby lead to alterations in the ***,5000μg/(kg·day)BPAF caused slighter,non-significant or even inverse alterations than the low dose of 50μg/(kg·day),displaying a dose-independent *** observations suggest that the the dose-independent effects of BPAF might be associated with oxidative stress and inflammatory responses caused by the high ***,our study highlights a risk of low-dose BPAF to human neuroendocrine regulation and metabolism.
Triboelectric nanogenerators(TENGs)have emerged as a promising approach for generating electricity and providing electrical stimuli in medical electronic *** their potential benefits,the clinical implementation of TEN...
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Triboelectric nanogenerators(TENGs)have emerged as a promising approach for generating electricity and providing electrical stimuli in medical electronic *** their potential benefits,the clinical implementation of TENGs faces challenges such as skin compliance and a lack of comprehensive assessment regarding their biosafety and ***,further research is imperative to overcome these limitations and unlock the full potential of TENGs in various biomedical *** this study,we present a flexible silk fibroin-based triboelectric nanogenerator(SFB-TENG)that features an on-skin substrate and is characterized by excellent skin compliance and air/water *** range of electrical output generated by the SFB-TENG was shown to facilitate the migration and proliferation of Hy926,NIH-3T3 and RSC96 ***,apoptosis of fibroblast NIH-3T3 cells was observed when the output voltage increased to more than 20 V at a frequency of 2 *** addition,the moderate electrical stimulation provided by the SFB-TENG promoted the cell proliferation cycle in Hy926 *** research highlights the efficacy of a TENG system featuring a flexible and skin-friendly design,as well as its safe operating conditions for use in biomedical *** findings position TENGs as highly promising candidates for practical applications in the field of tissue regeneration.
The ohmic contact interface between diamond and metal is essential for the application of diamond *** modification can significantly affect the contact performance and eliminate the interface polarization ***,the radi...
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The ohmic contact interface between diamond and metal is essential for the application of diamond *** modification can significantly affect the contact performance and eliminate the interface polarization ***,the radiation stability of a diamond detector is also sensitive to surface *** this work,the influence of surface modification technology on a diamond ohmic contact under high-energy radiation was *** radiation,the specific contact resistivities(ρc)between Ti/Pt/Au-hydrogen-terminated diamond(H-diamond)and Ti/Pt/Au-oxygenterminated diamond(O-diamond)were 2.0×10^(-4)W·cm^(2) and 4.3×10^(-3)Wcm^(2),*** 10 MeV electron radiation,the ρc of Ti/Pt/Au H-diamond and Ti/Pt/Au O-diamond were 5.3×10^(-3)W·cm^(2)and 9.1×10^(-3)W·cm^(2),*** rates of change of ρc of H-diamond and O-diamond after radiation were 2550%and 112%,*** electron radiation promotes bond reconstruction of the diamond surface,resulting in an increase in ρc.
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