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Frontiers of Information Technology & Electronic Engineering 2024年第8期25卷 1134-1144页

作者： Yitao YANG Lidong ZHANG school of Science Tianjin University of TechnologyTianjin 300384China

This article investigates the event-triggered adaptive neural network(NN)tracking control problem with deferred asymmetric time-varying(DATV)output *** deal with the DATV output constraints,an asymmetric time-varying barrier Lyapunov function(ATBLF)is first built to make the stability analysis and the controller construction ***,an event-triggered adaptive NN tracking controller is constructed by incorporating an error-shifting function,which ensures that the tracking error converges to an arbitrarily small neighborhood of the origin within a predetermined settling time,consequently optimizing the utilization of network *** is theoretically proven that all signals in the closed-loop system are semi-globally uniformly ultimately bounded(SGUUB),while the initial value is outside the constraint ***,a single-link robotic arm(SLRA)application example is employed to verify the viability of the acquired control algorithm.

关键词： Adaptive control Deferred asymmetric time-varying output constraints Error-shifting function Event-triggered control

Experimental,Numerical,and Analytical Studies on the Bending of Mechanically Lined Pipe

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China Ocean Engineering 2024年第2期38卷 221-232页

作者： WEI Wen-bin YUAN Lin ZHOU Jia-sheng LIU Zheng State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China school of Civil Engineering Tianjin UniversityTianjin 300072China school of Mechanical Engineering Tianjin UniversityTianjin 300072China

Mechanically lined pipe(MLP)is often used for offshore oil and gas transport because of its low cost and corrosion *** installation and operation,the pipe may undergo severe bending deformation,which causes the liner to separate from the outer pipe and buckles,affecting the stability of the whole *** this paper,the buckling response of MLP subjected to bending is investigated to clarify its bending characteristics by employing both experiments,numerical simulation,as theoretical *** types of MLPs were manufactured with GB 45 carbon steel(SLP)and Al 6061(ALP)used as the outer pipe material,*** hydraulic expansion and bending experiments of small-scale MLPs are *** addition to the ovalized shape of the cross-section for the SLP specimens,the copper liner was found to wrinkle on the compressive *** contrast,the liner of ALP remains intact without developing any wrinkling and collapse *** addition,a dedicated numerical framework and theoretical models were also *** was found both the manufacturing and bending responses of the MLP can be well reproduced,and the predicted maximum moment and critical curvatures are in good agreement with the experimental results.

关键词： lined pipe bending nonlinear ring theory buckling plasticity

Coexisting fast–slow dendritic traveling waves in a 3D-array electric field coupled neuronal network

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Chinese Physics B 2024年第6期33卷 614-626页

作者：魏熙乐任泽宇卢梅丽樊亚琴常思远 The tianjin Key Laboratory of Process Measurement and Control School of Electrical and Information EngineeringTianjin UniversityTianjin 300072China school of Information Technology Engineering Tianjin University of Technology and EducationTianjin 300074China

Coexistence of fast and slow traveling waves without synaptic transmission has been found in hhhippocampal tissues,which is closely related to both normal brain activity and abnormal neural activity such as epileptic discharge. However, the propagation mechanism behind this coexistence phenomenon remains unclear. In this paper, a three-dimensional electric field coupled hippocampal neural network is established to investigate generation of coexisting spontaneous fast and slow traveling waves. This model captures two types of dendritic traveling waves propagating in both transverse and longitude directions: the N-methyl-D-aspartate(NMDA)-dependent wave with a speed of about 0.1 m/s and the Ca-dependent wave with a speed of about 0.009 m/s. These traveling waves are synaptic-independent and could be conducted only by the electric fields generated by neighboring neurons, which are basically consistent with the in vitro data measured experiments. It is also found that the slow Ca wave could trigger generation of fast NMDA waves in the propagation path of slow waves whereas fast NMDA waves cannot affect the propagation of slow Ca waves. These results suggest that dendritic Ca waves could acted as the source of the coexistence fast and slow waves. Furthermore, we also confirm the impact of cellular spacing heterogeneity on the onset of coexisting fast and slow waves. The local region with decreasing distances among neighbor neurons is more liable to promote the onset of spontaneous slow waves which, as sources, excite propagation of fast waves. These modeling studies provide possible biophysical mechanisms underlying the neural dynamics of spontaneous traveling waves in brain tissues.

关键词： hippocampal network epileptiform dendritic oscillation traveling wave electric field coupling

Effect of applied electric fields on supralinear dendritic integration of interneuron

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Chinese Physics B 2024年第2期33卷 84-95页

作者：樊亚琴魏熙乐卢梅丽伊国胜 tianjin Key Laboratory of Process Measurement and Control School of Electrical and Information EngineeringTianjin UniversityTianjin 300072China school of Information Technology Engineering Tianjin University of Technology and EducationTianjin 300222China

Evidences show that electric fields(EFs)induced by the magnetic stimulation could modulates brain activities by regulating the excitability of GABAergic ***,it is still unclear how and why the EF-induced polarization affects the interneuron response as the interneuron receives NMDA synaptic *** the key role of NMDA receptor-mediated supralinear dendritic integration in neuronal computations,we suppose that the applied EFs could functionally modulate interneurons’response via regulating dendritic *** first,we build a simplified multi-dendritic circuit model with inhomogeneous extracellular potentials,which characterizes the relationship among EF-induced spatial polarizations,dendritic integration,and somatic *** performing model-based singular perturbation analysis,it is found that the equilibrium point of fast subsystem can be used to asymptotically depict the subthreshold input–output(sI/O)relationship of dendritic *** predicted that EF-induced strong depolarizations on the distal dendrites reduce the dendritic saturation output by reducing driving force of synaptic input,and it shifts the steep change of sI/O curve left by reducing stimulation threshold of triggering NMDA ***,the EF modulation prefers the global dendritic integration with asymmetric scatter distribution of NMDA ***,we identify the respective contribution of EF-regulated dendritic integration and EF-induced somatic polarization to an action potential generation and find that they have an antagonistic effect on AP generation due to the varied NMDA spike threshold under EF stimulation.

关键词： GABAergic interneuron electrical field supralinear dendritic integration action potential generation

An Analytical Method for Delineating Feasible Region for PV Integration Capacities in Net-zero Distribution Systems Considering Battery Energy Storage System Flexibility

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 475-487页

作者： Shida Zhang Shaoyun Ge Hong Liu Guocheng Hou Chengshan Wang school of Electrical and Information Engineering Tianjin UniversityTianjin 300072China

To provide guidance for photovoltaic(PV)system integration in net-zero distribution systems(DSs),this paper proposes an analytical method for delineating the feasible region for PV integration capacities(PVICs),where the impact of battery energy storage system(BESS)flexibility is ***,we introduce distributionally robust chance constraints on network security and energy/carbon net-zero requirements,which form the upper and lower bounds of the feasible ***,the formulation and solution of the feasible region is *** resulting analytical expression is a set of linear inequalities,illustrating that the feasible region is a polyhedron in a high-dimensional space.A procedure is designed to verify and adjust the feasible region,ensuring that it satisfies network loss constraints under alternating current(AC)power *** studies on the 4-bus system,the IEEE 33-bus system,and the IEEE 123-bus system verify the effectiveness of the proposed *** is demonstrated that the proposed method fully captures the spatio-temporal coupling relationship among PVs,loads,and BESSs,while also quantifying the impact of this relationship on the boundaries of the feasible region.

关键词： Net-zero distribution system photovoltaic(PV)integration capacity feasible region battery energy storage system(BESS).

A semantic segmentation-based underwater acoustic image transmission framework for cooperative SLAM

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Defence Technology（防务技术） 2024年第3期33卷 339-351页

作者： Jiaxu Li Guangyao Han Shuai Chang Xiaomei Fu school of Marine Science and Technology Tianjin UniversityTianjin 300072China

With the development of underwater sonar detection technology,simultaneous localization and mapping(SLAM)approach has attracted much attention in underwater navigation field in recent *** the weak detection ability of a single vehicle limits the SLAM performance in wide ***,cooperative SLAM using multiple vehicles has become an important research *** key factor of cooperative SLAM is timely and efficient sonar image transmission among underwater ***,the limited bandwidth of underwater acoustic channels contradicts a large amount of sonar image *** is essential to compress the images before ***,deep neural networks have great value in image compression by virtue of the powerful learning ability of neural networks,but the existing sonar image compression methods based on neural network usually focus on the pixel-level information without the semantic-level *** this paper,we propose a novel underwater acoustic transmission scheme called UAT-SSIC that includes semantic segmentation-based sonar image compression(SSIC)framework and the joint source-channel codec,to improve the accuracy of the semantic information of the reconstructed sonar image at the *** SSIC framework consists of Auto-Encoder structure-based sonar image compression network,which is measured by a semantic segmentation network's *** that sonar images have the characteristics of blurred target edges,the semantic segmentation network used a special dilated convolution neural network(DiCNN)to enhance segmentation accuracy by expanding the range of receptive *** joint source-channel codec with unequal error protection is proposed that adjusts the power level of the transmitted data,which deal with sonar image transmission error caused by the serious underwater acoustic *** results demonstrate that our method preserves more semantic information,with advantages over existing methods at the sa

关键词： Semantic segmentation Sonar image transmission Learning-based compression

Investigation on the Velocity-Dependent Adhesion Hysteresis via Molecular Dynamics Simulation

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Acta Mechanica Solida Sinica 2024年第3期37卷 423-429页

作者： Jinshan He Yiran Li Zhaoyang Ma Ganyun Huang Department of Mechanics School of Mechanical EngineeringTianjin UniversityTianjin300350China

Adhesion plays an important role in miniaturized devices and technologies,which depends not only on indentation depth but also on the history of contact making and breaking,giving rise to adhesion *** the present work,adhesion hysteresis has been investigated via molecular dynamics simulations on approaching and retracting a rigid tip to and from a *** results show that hysteresis in the force-displacement curve that depends on approaching and retraction velocities arises under both elastic and plastic *** underlying mechanisms have been *** implications of the results in friction have been discussed briefly.

关键词： Adhesion hysteresis Molecular dynamics simulation Contact instability Plastic deformation

Permeable and robust polymer-silica hybrid armor on cell catalyst for sustainable biomanufacturing

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Particuology 2024年第9期92卷 106-112页

作者： Yiran Cheng Zhenhua Wu Boyu Zhang Jiaxu Zhang Jiafu Shi Zhongyi Jiang school of Environmental Science and Engineering Tianjin UniversityTianjin300072China Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China

Inactivated cell catalysis is one of several central techniques in green biomanufacturing ***,the instability and leakage of enzymes in inactivated cell severely restrict the practical applications of inactivated cell *** armor on the surface of inactivated cells affords a feasible and effective strategy to enhance the stability of cells while commonly lowering the ***,polymer-silica hybrid armor(PSHA)is directly generated on the surface of enzyme-containing *** branched structure of PEI enables higher porosity of cell@PSHA,exhibiting 1.52-fold enhancement in substrate permeability by contrast with cell@silica armor(SA).The electrostatic interactions(NH_(3)^(+)with O^(−))and hydrogen bonding(N⋯H or O⋯H)interactions between structural units enables higher stability of cell@PSHA,showing 3.13-fold elevation in Young's modulus compared with cell@*** a result,the cell@PSHA can catalyze continuous conversion of starch to tagatose for 15 batches over 969 h,with an average yield of 77.76 g L^(−1).

关键词： Biomanufacturing Wholecell catalysis Polymer-silica hybrid armor Tagatose production Starch conversion

Potential application of radiant floor cooling systems for residential buildings in different climate zones

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Building Simulation 2024年第4期17卷 543-560页

作者： Mengying Cui Yang Song Yudong Mao Kaimin Yang Jiying Liu Zhe Tian school of Thermal Engineering Shandong Jianzhu UniversityJinan250101China school of Environmental Science and Engineering Tianjin UniversityTianjin300072China Key Lab of Building Environment and Energy of tianjin Tianjin UniversityTianjin300072China

A radiant floor cooling system(RFCS)is a high-comfort and low energy consumption system suitable for residential *** floor systems usually work with fresh air,and their operating performance is affected by climatic *** and outdoor environmental disturbances and the system’s control strategy affect the indoor thermal comfort and energy efficiency of the ***,a multi-story residential building model was established in this *** system simulation program was used to study the operation dynamics of three control strategies of the RFCS based on the calibrated ***,the performance of the control strategies in five climate zones in China were compared using multi-criteria decision-making in *** results show that control strategy has a negligible effect on condensation risk,but the thermal comfort and economic performance differ for different control *** adaptability of different control strategies varies in different climate zones based on the consideration of multiple *** performance of the direct-ground cooling source system is better in Hot summer and warm winter *** variable air volume control strategy scores higher in Serve cold and Temperate zones,and the hours exceeding thermal comfort account for less than 3%of the total simulation ***,it is suggested to choose the RFCS control strategy for residential buildings according to the climate zone characteristics,to increase the energy *** results provide a reliable reference for implementing RFCSs in residential buildings.

关键词： control strategy radiant floor cooling system residential building energy efficiency climate zones

Mg-doped,carbon-coated,and prelithiated SiO_(x) as anode materials with improved initial Coulombic efficiency for lithium-ion batteries

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Carbon Energy 2024年第3期6卷 204-214页

作者： Bin Liu Jie Liu Cheng Zhong Wenbin Hu Key Laboratory of Advanced Ceramics and Machining Technology(Ministry of Education) School of Materials Science and EngineeringTianjin UniversityTianjinChina tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjinChina Joint school of National University of Singapore and tianjin University TianjinChina International Campus of tianjin University Binhai New CityFuzhouChina

Silicon suboxide(SiO_(x),x≈1)is promising in serving as an anode material for lithium-ion batteries with high capacity,but it has a low initial Coulombic efficiency(ICE)due to the irreversible formation of lithium silicates during the first *** this work,we modify SiO_(x) by solid-phase Mg doping reaction using low-cost Mg powder as a reducing *** show that Mg reduces SiO_(2) in SiO_(x) to Si and forms MgSiO_(3) or Mg_(2)SiO_(4).The MgSiO_(3) or Mg_(2)SiO_(4) are mainly distributed on the surface of SiO_(x),which suppresses the irreversible lithium-ion loss and enhances the ICE of SiO_(x).However,the formation of MgSiO_(3) or Mg_(2)SiO_(4) also sacrifices the capacity of SiO_(x).Therefore,by controlling the reaction process between Mg and SiO_(x),we can tune the phase composition,proportion,and morphology of the Mg-doped SiO_(x) and manipulate the *** obtain samples with a capacity of 1226 mAh g^(–1) and an ICE of 84.12%,which show significant improvement over carbon-coated SiO_(x) without Mg *** the synergistical modification of both Mg doping and prelithiation,the capacity of SiO_(x) is further increased to 1477 mAh g^(–1) with a minimal compromise in the ICE(83.77%).

关键词： initial Coulombic efficiency lithium-ion batteries magnesium doping prelithiation silicon suboxide