The Al2O3 ceramic substrate exhibits significant potential in advanced packaging due to its superior comprehensive properties but is hindered by complex technology (separate processing of ceramic sheets and circuits),...
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Robot teleoperation plays an important role in industrial manufacturing in unknown and dangerous environments beyond human *** telerobotic manufacturing tasks,environmental interaction forces may vary significantly fr...
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Robot teleoperation plays an important role in industrial manufacturing in unknown and dangerous environments beyond human *** telerobotic manufacturing tasks,environmental interaction forces may vary significantly from task to ***,it is crucial to provide operators with the specific proportional feedback of environmental interaction forces to enhance their environmental awareness and manipulation ***,variable time delays and various scales of environmental interaction force feedback seriously affect the system stability,which should be rigorously addressed when designing control *** cope with these difficulties,a position and scaled force tracking control framework is proposed and the LyapunovKrasovskii theory is used to obtain a simple algebraic stability criterion with the scaling factor of the environmental interaction force *** addition,a low-pass filter-based radial basis function neural network is designed to avoid the effect of the measurement noise and the sudden change of the non-passive environmental interaction force on the system *** with different controllers in various telerobotic manufacturing tasks such as heavy lifting,cutting,and polishing,our proposed method achieves better position and scaled force tracking performance.
Laser-Induced Graphene (LIG) is regarded as a promising sensor carrier due to its inherent three-dimensional porous structure. However, as two mutually exclusive properties of the pressure sensor, sensitivity and work...
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Laser-Induced Graphene (LIG) is regarded as a promising sensor carrier due to its inherent three-dimensional porous structure. However, as two mutually exclusive properties of the pressure sensor, sensitivity and working range are difficult to be further improved by the single porous structure. Inspired by the unique geometry of Oxalis corniculata L. leaves, we here propose a novel method consist of laser pre-etching and inducing steps to fabricate LIG-based electrodes with a two-stage architecture featuring microjigsaw and microporous structures. The following injection of liquid-silicone significantly improves the friction resistance and bending reliability of LIG materials. The interface contact between external microjigsaw structures induces substantial resistance changes, and the internal microporous structure exhibits reversibility during dynamic deformation. Consequently, the jigsaw-like pressure sensor achieves a balanced performance with sensitivities of 3.64, 1.20 and 0.03 kPa^(- 1) in pressure range of 0 -20, 20 - 40 and 40 - 150 kPa, respectively. The bionic LIG-based pressure sensor serves as the core component and further integrated with an all-in-one wireless transmission system capable of monitoring various health parameters such as subtle pulse rates, heartbeat rhythms, sounds, etc., indicating broad prospects in future wearable electronics.
The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression *** establishing the constitutive equations for simulating th...
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The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression *** establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow *** concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present.
Multiarmed bandit(MAB) models are widely used for sequential decision-making in uncertain environments, such as resource allocation in computer communication systems.A critical challenge in interactive multiagent syst...
Multiarmed bandit(MAB) models are widely used for sequential decision-making in uncertain environments, such as resource allocation in computer communication systems.A critical challenge in interactive multiagent systems with bandit feedback is to explore and understand the equilibrium state to ensure stable and tractable system performance.
This paper proposes an innovative simultaneous optimization approach for single and multi-component mass exchanger network synthesis (MENS). A retrofitted stage-wise superstructure and a parallelized random walk algor...
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This paper proposes an innovative simultaneous optimization approach for single and multi-component mass exchanger network synthesis (MENS). A retrofitted stage-wise superstructure and a parallelized random walk algorithm with compulsive evolution (RWCE) are adopted. An iterative calculation method is designed to satisfy the requirements of multi-component mass transfer, with a relaxation for the outlet composition of the lean streams. The parametric analysis shows that the relaxation coefficient plays a major role in driving the convergence of the method. To improve the robustness of the established model, an adaptive relaxation coefficient strategy is implemented for multi-component MENS problems. In a divergence situation, the outlet concentration of the lean stream can be adjusted automatically by a random relaxation coefficient. Finally, three industrial MENS examples are considered in this work, whose total annual cost (TAC) are reduced by 7179, 2212, and 551 $·year^(-1). The corresponding optimization times are obtained to be 336, 125, and 145 s. The results indicate improvements in the economy and time, demonstrating that the parallelized RWCE can yield an optimal TAC and optimization efficiency compared to previous results. Overall, the adaptive relaxation coefficient strategy enhances the convergence for multi-component MENS problems.
This paper studies finite-time stability and instability theorems in the probability sense for stochastic nonlinear timevarying systems. Firstly, a new sufficient condition is proposed to guarantee that the considered...
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This paper studies finite-time stability and instability theorems in the probability sense for stochastic nonlinear timevarying systems. Firstly, a new sufficient condition is proposed to guarantee that the considered system has a global ***, we propose new finite-time stability and instability criteria that relax the constraints on LV(the infinitesimal operator of Lyapunov function V) by the uniformly asymptotically stable function. On the one hand, these obtained results make up for the shortcomings of the existing results. On the other hand, the new finite-time stability theorems can be viewed as natural extensions of the existing results and also allow LV to be indefinite(negative or positive) rather than just only allow LV < ***, some simulation examples verify the validity of the theoretical results.
The Design and manufacturing of a noble piezoresistive pressure sensor(PS) for subtle pressures(<1 kPa) were presented. Meanwhile, in the studies conducted in the field of pressure sensors, the measurement of subtl...
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The Design and manufacturing of a noble piezoresistive pressure sensor(PS) for subtle pressures(<1 kPa) were presented. Meanwhile, in the studies conducted in the field of pressure sensors, the measurement of subtle pressures has received less attention. The limitations in the inherent gauge factor in silicon, have led to the development of polymer and composite resistive sensitive elements. However,in the development of resistance sensing elements, the structure of composite elements with reinforcement core has not been used. The proposed PS had a composite sandwich structure consisting of a nanocomposite graphene layer covered by layers of PDMS at the bottom and on the top coupled with a polyimide(PI) core. Various tests were performed to analyze the PS. The primary design target was improved sensitivity, with a finite-element method(FEM) utilized to simulate the stress profile over piezoresistive elements and membrane deflection at various pressures. The PS manufacturing process is based on Laser-engraved graphene(LEG) technology and PDMS casting. Experimental data indicated that the manufactured PS exhibits a sensitivity of 67.28 mV/kPa for a pressure range of 30-300 Pa in ambient temperature.
A reasonable process plan is an important basis for implementing wire arc additive and subtractive hybrid manufacturing(ASHM), and a new optimization method is proposed. Firstly, the target parts and machining tools a...
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The pollution especially organic dyes pollution of water resources is an urgent issue to be *** is crucial to develop highly efficient,low cost and recyclable heterogeneous catalysts for wastewater *** this study,a he...
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The pollution especially organic dyes pollution of water resources is an urgent issue to be *** is crucial to develop highly efficient,low cost and recyclable heterogeneous catalysts for wastewater *** this study,a heterogeneous Fenton catalyst loaded with Fe_(3)O_(4)nanoparticles was prepared by one step pyrolysis using natural crop waste corncob as carbon *** prepared porous carbon catalyst can effectively degrade methyl orange(MO,25 mg·L^(-1))at room temperature,and the degradation rate is 99.7%.In addition to high catalytic degradation activity,the layered porous carbon structure of the catalyst also provides high stability and *** degradation rate can be maintained above 93%after 10 ***,the prepared catalyst is magnetic,which makes the catalyst easy to recycle in practical *** addition,the prepared Fe3O4/RCC catalyst has efficient Fenton degradation activity for bisphenol A(BPA)(96.9%)and antibiotic tetracycline hydrochloride(TC-HCl)(95.5%),which proves that it has universal applicability for the degradation of most organic *** study provides a feasible and scalable strategy to prepare a heterogeneous Fenton catalyst treating wastewater and high-value utilization of biomass waste.
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