A non-contact method for millimeter-scale inspection of material surface flatness via Laser-Induced Breakdown Spectroscopy(LIBS)is investigated *** experiment is performed using a planished surface of an alloy steel s...
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A non-contact method for millimeter-scale inspection of material surface flatness via Laser-Induced Breakdown Spectroscopy(LIBS)is investigated *** experiment is performed using a planished surface of an alloy steel sample to simulate its various flatness,ranging from 0 to 4.4 mm,by adjusting the laser focal plane to the surface distance with a step length of 0.2 *** is found that LIBS measurements are successful in inspecting the flatness differences among these simulated cases,implying that the method investigated here is *** is also found that,for achieving the inspection of surface flatness within such a wide range,when univariate analysis is applied,a piecewise calibration model must be *** is due to the complex dependence of plasma formation conditions on the surface flatness,which inevitably complicates the inspection *** solve the problem,a multivariate analysis with the help of Back-Propagation Neural Network(BPNN)algorithms is applied to further construct the calibration *** detailed analysis of the model performance,we demonstrate that a unified calibration model can be well established based on BPNN algorithms for unambiguous millimeter-scale range inspection of surface flatness with a resolution of about 0.2 mm.
Due to ever-growing soccer data collection approaches and progressing artificial intelligence(AI) methods, soccer analysis, evaluation, and decision-making have received increasing interest from not only the professio...
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Due to ever-growing soccer data collection approaches and progressing artificial intelligence(AI) methods, soccer analysis, evaluation, and decision-making have received increasing interest from not only the professional sports analytics realm but also the academic AI research community. AI brings gamechanging approaches for soccer analytics where soccer has been a typical benchmark for AI research. The combination has been an emerging topic. In this paper, soccer match analytics are taken as a complete observation-orientation-decision-action(OODA) *** addition, as in AI frameworks such as that for reinforcement learning, interacting with a virtual environment enables an evolving model. Therefore, both soccer analytics in the real world and virtual domains are discussed. With the intersection of the OODA loop and the real-virtual domains, available soccer data, including event and tracking data, and diverse orientation and decisionmaking models for both real-world and virtual soccer matches are comprehensively reviewed. Finally, some promising directions in this interdisciplinary area are pointed out. It is claimed that paradigms for both professional sports analytics and AI research could be combined. Moreover, it is quite promising to bridge the gap between the real and virtual domains for soccer match analysis and decision-making.
The high-speed maglev vehicle/guideway coupled model is an essential simulation tool for investigating vehicle dynamics and mitigating coupled *** improve its accuracy efficiently,this study investigated a hierarchica...
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The high-speed maglev vehicle/guideway coupled model is an essential simulation tool for investigating vehicle dynamics and mitigating coupled *** improve its accuracy efficiently,this study investigated a hierarchical model updating method integrated with field ***,a high-speed maglev vehicle/guideway coupled model,taking into account the real effect of guideway material properties and elastic restraint of bearings,was developed by integrating the finite element method,multi-body dynamics,and electromagnetic levitation ***,simultaneous in-site measurements of the vehicle/guideway were conducted on a high-speed maglev test line to analyze the system response and structural modal *** the hierarchical updating,an Elman neural network with the optimal Latin hypercube sampling method was used to substitute the FE guideway model,thus improving the computational *** multi-objective particle swarm optimization algorithm with the gray relational projection method was applied to hierarchically update the parameters of the guideway layer and magnetic force layer based on the measured modal parameters and the electromagnet vibration,***,the updated coupled model was compared with the field measurements,and the results demonstrated the model’s accuracy in simulating the actual dynamic response,validating the effectiveness of the updating method.
A reasonable planting density is vital for wheat resource efficiency and yield enhancement. However, systematic research on the impact of spraying TiO2-NPs on wheat growth, metabolism, and stress tolerance cultivated ...
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A reasonable planting density is vital for wheat resource efficiency and yield enhancement. However, systematic research on the impact of spraying TiO2-NPs on wheat growth, metabolism, and stress tolerance cultivated in cadmium (Cd)-contaminated soil is limited, especially in integration with planting density, requiring a deeper understanding. Our study showed that spraying with 3.1 mg per plant TiO2-NPs (in pots) and 21.6 mg m-2 TiO2-NPs combined with high planting densities (in the field) both significantly reduced the Cd content in wheat grains by 27.9 and 35.7%, respectively. Immobilization of subcellular water-soluble Cd and the conversion of Cd into inactive plant components in leaves were the primary reasons for this reduction. Metabolomics further revealed the up-regulation of metabolites related to antioxidant activity, plant stress resistance, growth promotion, and the tricarboxylic acid (TCA) cycle, which promotes plant growth, enhances wheat antioxidant enzyme activity, and alleviates oxidative stress. Transcriptomic analysis validated the association between these responses and improved plant stress resistance, with genes such as MYB, WRKY, P450, and Cd membrane transport-related genes like ABCG2 and ABCC3 contributing to the decrease in Cd levels in wheat. Importantly, the Cd-associated human health risk index was also reduced via foliar TiO2-NPs application. Overall, foliar spraying of TiO2-NPs combined with high plant density was beneficial in alleviating Cd levels in wheat grains, limiting the risk of Cd exposure to human health via the food chain.
Infrastructure-as-a-Service(IaaS)cloud platforms offer resources with diverse buying *** can run an instance on the on-demand market which is stable but expensive or on the spot market with a significant ***,users hav...
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Infrastructure-as-a-Service(IaaS)cloud platforms offer resources with diverse buying *** can run an instance on the on-demand market which is stable but expensive or on the spot market with a significant ***,users have to carefully weigh the low cost of spot instances against their poor *** instances will be revoked when the revocation event ***,an important problem that an IaaS user faces now is how to use spot in-stances in a cost-effective and low-risk *** on the replication-based fault tolerance mechanism,we propose an on-line termination algorithm that optimizes the cost of using spot instances while ensuring operational *** prove that in most cases,the cost of our proposed online algorithm will not exceed twice the minimum cost of the optimal of-fline algorithm that knows the exact future a *** a large number of experiments,we verify that our algorithm in most cases has a competitive ratio of no more than 2,and in other cases it can also reach the guaranteed competitive ratio.
Enhanced CO_(2)sequestration(ECS)within low-permeable reservoirs during CO_(2)-enhanced oil recovery(CO_(2)-EOR)processes has gained significant interest,primarily driven by the need to mitigate the greenhouse effect ...
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Enhanced CO_(2)sequestration(ECS)within low-permeable reservoirs during CO_(2)-enhanced oil recovery(CO_(2)-EOR)processes has gained significant interest,primarily driven by the need to mitigate the greenhouse effect caused by excessive CO_(2)*** this work,the in-situ nuclear magnetic resonance(NMR)is applied to investigate the oil production and CO_(2)sequestration within the micropores of low-permeable ***,the impact of CO_(2)-water-oil-rock reactions on CO_(2)-EOR and CO_(2)sequestration is studied by analysis of the changes in minerals,pore structures,and wettability of cores by scanning electron microscopy(SEM),X-ray diffraction(XRD),and contact angle measurements with the experiments of CO_(2)-water-oil-rock interaction in the high-temperature and high-pressure(HT-HP)*** results reveal that the residual water saturation(Swr),CO_(2)injection pressure,and the interaction among CO_(2),water,oil,and rock all exerted a considerable impact on oil recovery and CO_(2)sequestratio *** with the oil recovery and CO_(2)sequestration of the two oil-satu rated cores(Core No.2 and Core No.3)after CO_(2)injection,the accumulated oil recoveries of the two cores with S_(wr)=0.5are enhanced by 1.8%and 4.2%,and the CO_(2)sequestration ratios are increased by 3%and 10%,*** with the CO_(2)-water-rock that occurred in oil-saturated cores,the CO_(2)-water-rock reaction for cores(S_(wr)=0.5)is more intense,which leads to the formation of more hydrophilic rock on pore surfaces after the reaction,thereby reducing the adhesion work of CO_(2)stripping *** oil and water mixtures in pores also inhibit CO_(2)premature breakthrough from cores,therefore expanding the swept volume of CO_(2)in ***,oil recovery and CO_(2)sequestration in small pores of cores are significantly improved with the rise in CO_(2)injection pressure due to the enhanced driving pressure degree and also the improved mutual solubility and mass tr
Partial nitrification-Anammox (PN-A) is a cost-effective, environmentally friendly, and efficient method for removing ammonia (NH4+-N) pollutants from water. However, the limited accumulation of nitrite (NO2--N) repre...
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Partial nitrification-Anammox (PN-A) is a cost-effective, environmentally friendly, and efficient method for removing ammonia (NH4+-N) pollutants from water. However, the limited accumulation of nitrite (NO2--N) represents a bottleneck in the development of PN-A processes. To address this issue, this study developed a composite carrier loaded with nano zero-valent iron (nZVI) and zeolite to enhance NO2--N accumulation during short-cut nitrification. The modified composite carrier revealed electropositive, hydrophilicity, and surface roughness. These surface characteristics correlate positively with the carrier's total biomass adsorption capacity;the initial adsorption of microorganisms by the composite carrier was increased by 8.7 times. Zeolite endows the carrier with an NH4+-N adsorption capacity of 4.50 mg/g carrier. The entropy-driven ammonia adsorption process creates an ammonia-rich microenvironment on the surface of the carrier, providing effective inhibition of nitrite-oxidizing bacteria (NOB). In tests conducted with a moving bed biofilm reactor and a sequencing batch reactor, the composite carrier achieved a 95% NH4+-N removal efficiency, a NO2--N accumulation efficiency of 78%, and a doubling in total nitrogen removal efficiency. This composite carrier enhances NO2--N accumulation by preventing biomass washout, inhibiting NOB, and enriching PN-A functional bacteria, suggesting its potential for large-scale, stable PN-A applications.
Chiral inorganic materials with unique asymmetries hold promising potential in several fields,including catalytic ***,imparting structural chirality to inorganic materials presents substantial challenges that hinders ...
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Chiral inorganic materials with unique asymmetries hold promising potential in several fields,including catalytic ***,imparting structural chirality to inorganic materials presents substantial challenges that hinders their exploration in many *** this study,we report a simple two-step method for synthesizing structurally chiral nickel oxides(NiO)nanostructures and demonstrate that the chiral-induced spin-selective mechanism enhances the catalytic performance during electrocatalytic oxygen evolution reaction(OER).Compared to their achiral NiO counterparts,the chiral NiO nanostructures not only improve the reaction kinetics(a 60 mV reduction in overpotential),but also effectively modulate the reaction pathway to inhibit the byproduct hydrogen peroxide *** neutral conditions,this modulation results in a 4.5-fold reduction in hydrogen peroxide *** work enriches the variety of chiral inorganic nanomaterials and paves the way for the development and application of chiral inorganic nanomaterials in spin-dependent processes.
Based on the relevant theories of M-matrix and the Lyapunov stability technique, this paper investigates the multistability of equilibrium points and periodic solutions for Clifford-valued memristive Cohen-Grossberg n...
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Based on the relevant theories of M-matrix and the Lyapunov stability technique, this paper investigates the multistability of equilibrium points and periodic solutions for Clifford-valued memristive Cohen-Grossberg neural networks. With the help of Cauchy convergence criterion, the exponential stability inequality is derived. The system has [Pi(A)(K-A+1)](n) locally exponentially stable equilibrium points and periodic solutions, which greatly increases the number of solutions compared with the existing Cohen-Grossberg neural networks, where the K-A is a Clifford-valued and there is no limitation of linearity and monotonicity for activation functions. Furthermore, the attraction basins of stable periodic solutions are obtained, and it is proved that the basins can be enlarged. It is worth mentioning that the results can also be used to discuss the multistability of equilibrium points, periodic solutions, and almost periodic solutions for real-valued, complex-valued, and quaternion-valued memristive Cohen-Grossberg neural networks. Finally, two numerical examples with simulations are taken to verify the theoretical analysis.
Mining dump trucks play an important role in engineering construction and resource extraction. Current research mainly focuses on the dynamic modeling and reliability analysis of the vehicle frame, suspension and over...
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Mining dump trucks play an important role in engineering construction and resource extraction. Current research mainly focuses on the dynamic modeling and reliability analysis of the vehicle frame, suspension and overall model. However, with the development of electric drive, the wheel hub system has become an important component in mining truck equipment. This paper investigates the multi-body modeling of a mining truck's hub drive reduction system in order to analyze its output characteristics including the stability of the angular velocity of its planetary carriers and the fluctuations in its meshing forces. A bench experiment was also conducted to verify the accuracy and stability of the proposed modeling. And the simulation results revealed that the fluctuations in the angular velocity of the planetary carriers were primarily influenced by the excitation from the hub motor's input and the meshing forces between the gears of the reducers, which were mainly determined by the contact stiffness, damping, and clearance value during gear contact.
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