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Digital Communications and Networks 2024年第2期10卷 282-291页

作者： Jiachen Yang Meng xi Jiabao Wen Yang Li Houbing Herbert Song school of Electrical and Information Engineering Tianjin UniversityTianjin300072China Security and Optimization for Networked Globe Laboratory(SONG Lab) Embry-Riddle Aeronautical UniversityDaytona BeachFL32114USA

The Autonomous Underwater Glider(AUG)is a kind of prevailing underwater intelligent internet vehicle and occupies a dominant position in industrial applications,in which path planning is an essential *** to the complexity and variability of the ocean,accurate environment modeling and flexible path planning algorithms are pivotal *** traditional models mainly utilize mathematical functions,which are not complete and *** existing path planning algorithms depend on the environment and lack *** overcome these challenges,we propose a path planning system for underwater intelligent internet *** applies digital twins and sensor data to map the real ocean environment to a virtual digital space,which provides a comprehensive and reliable environment for path *** design a value-based reinforcement learning path planning algorithm and explore the optimal network structure *** path simulation is controlled by a closed-loop model integrated into the terminal vehicle through edge *** integration of state input enriches the learning of neural networks and helps to improve generalization and *** task-related reward function promotes the rapid convergence of the *** experimental results prove that our reinforcement learning based path planning algorithm has great flexibility and can effectively adapt to a variety of different ocean conditions.

关键词： Digital twins Reinforcement learning Edge computing Underwater intelligent internet vehicle Path planning

The study of adsorption gas sensor based carbon nanotube film

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science china(Technological sciences) 2005年第4期48卷 372-384页

作者： LI xin1, LIU Junhua2.& ZHU Changchun1 1. school of Electronic and Information Engineering, xi’an jiaotong university,{2., china 2. school of Electric Engineering, xi’an jiaotong university,{2., china 1. school of Electronic and Information Engineering Xi’an Jiaotong University 710049 Xi’an China 2. school of Electric Engineering Xi’an Jiaotong University 710049 Xi’an China

The study of gas sensitivity of multi-wall carbon nanotubes (MWNTs), which is deposited by low press chemical vapor deposition (LPCVD), is presented. The results show that the pure MWNTs are not sensitive to the gases measured, while the composite film consisting of the MWNTs and silicon dioxide is sensitive to the methane, the hydrogen and the acetylene. The MWNTs and silicon dioxide composite film have the capacitance characteristic because of the formation of Schottky junctions within the MWNTs. The chemistry adsorption of the gas measured on the surface of the MWNTs affects the space discharge area of the Schottky junction, so that the dielectric constant changes with the gas concentration. That is why the gas is sensed.

关键词： gas sensor, carbon nanotubes, low press chemical vapor deposition, scatter.

Descriptors-based machine-learning prediction of cetane number using quantitative structure–property relationship

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Energy and AI

Energy and AI 2024年第3期17卷 168-178页

作者： Rodolfo S.M.Freitas xi Jiang school of Engineering and Materials science Queen Mary University of LondonMile End RoadLondonE14NSUK

The physicochemical properties of liquid alternative fuels are important but difficult to measure/predict, especially when complex surrogate fuels are concerned. In the present work, machine learning is used to develop quantitative structure–property relationship models. The fuel chemical structure is represented by molecular descriptors, allowing the linking of important features of the fuel composition and key properties of fuel utilization. Feature selection is employed to select the most relevant features that describe the chemical structure of the fuel and several machine learning algorithms are tested to construct interpretable models. The effectiveness of the methodology is demonstrated through the development of accurate and interpretable predictive models for cetane numbers, with a focus on understanding the link between molecular structure and fuel properties. In this context, matrix-based descriptors and descriptors related to the number of atoms in the molecule are directly linked with the cetane number of hydrocarbons. Furthermore, the results showed that molecular connectivity indices play a role in the cetane number for aromatic molecules. Also, the methodology is extended to predict the cetane number of ester and ether molecules, leveraging the design of alternative fuels towards fully sustainable fuel utilization.

关键词： Chemical descriptors Quantitative structure-property relationship Machine learning Cetane number Fuel design

Heterostructure of 2. MoSe_(2. nanosheets vertically grown on bowllike carbon for high-performance sodium storage

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Nano Research 2024年第5期17卷 4023-4030页

作者： Nianxiang Shi Guangzeng Liu Baojuan xi Xuguang An Changhui Sun Shenglin xiong school of Chemistry and Chemistry Engineering Qilu Normal UniversityJinan 250200China school of Chemistry and Chemical Engineering Shandong UniversityJinan 250100China school of Mechanical Engineering Chengdu UniversityChengdu 610106China

Transition metal dichalcogenides are attractive anode materials for sodium ion batteries(SIBs)due to their high theoretical capacity and large interlayer ***,its practical application is hampered by the sluggish kinetics of Na^(+)insertion and structure collapse caused by Na^(+)insertion/***,the heterostructures of MoSe_(2. nanosheets vertically growing on bowl-like carbon(MoSe_(2.@C)are designed and prepared by a template method coupled with selenization treatment to boost storage sodium *** hollow and collapse could provide enough storage space for Na^(+)and alleviate the volume expansion during the charge/discharge ***_(2. nanosheets vertically grown on carbon could expose more active sites for adsorbing Na^(+)to enhance the utilization rate of electrode ***,building heterostructures by combining different phase components could facilitate Na^(+)diffusion and advance reaction *** from these merits,the bowl-like MoSe_(2.@C shows outstanding reversible capacity(356.8 mAh·g^(-1) after 1500 cycles at 1 A·g^(-1))and remarkable rate performance(2.9.9 mAh·g^(-1)10 A·g^(-1)).

关键词： MoSe_(2.nanosheets bowl-like carbon heterostructure sodium ion batteries

Effect of Mn Addition and Heat Treatment on the Corrosion Behaviour of Mg-Ag-Mn Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 665-677页

作者： You Lv Yupeng Zhang xi Liu Zehua Dong xiaorong Zhou xinxin Zhang Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074China Hubei Engineering Research Centre for Biomaterials and Medical Protective Materials Huazhong University of Science and TechnologyWuhan430074China Corrosion and Protection Centre Department of MaterialsThe University of ManchesterManchesterM139PLUK

The high corrosion sensitivity and the potential bio-toxicity of Mg-Ag alloys limit their wide applications for the production of implanted devices. In the present work, Mn is added into the Mg-Ag alloy to optimize its corrosion behaviour. The corrosion behaviour of Mg-Ag-Mn alloys is investigated with the underlying microstructural factors examined. The Mg-Ag alloy with 2.wt% Mn exhibits the highest corrosion resistance after post-casting heat treatment at 440 ℃. The addition of Mn results in α-Mn phase with the incorporation of Fe, which suppresses the cathodic activity of impurity Fe. Further, heat treatment of the cast alloys homogenizes the distribution of Ag and promotes the precipitation of α-Mn phase. The former removes Ag segregations as potential cathodes;the latter promotes a more uniform distribution of cathodes and, therefore, prevents localized corrosion.

关键词： Mg-Ag alloy Mn addition Post-casting heat treatment Cathodic activity Corrosion mechanism

Variational Neural Inference Enhanced Text Semantic Communication System

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china Communications 2024年第7期21卷 50-64页

作者： Zhang xi Zhang Yiqian Li Congduan Ma xiao school of Electronics and Communication Engineering Sun Yat-Sen UniversityShenzhen 518107China Guizhou university State Key Laboratory of Public Big Data Guiyang 550025China Shenzhen Key Laboratory of Navigation and Communication Integration Shenzhen 518107China school of Computer science and Engineering Sun Yat-Sen UniversityGuangzhou 510006China

Recently,deep learning-based semantic communication has garnered widespread attention,with numerous systems designed for transmitting diverse data sources,including text,image,and speech,*** efforts have been directed toward improving system performance,many studies have concentrated on enhancing the structure of the encoder and ***,this often overlooks the resulting increase in model complexity,imposing additional storage and computational burdens on smart ***,existing work tends to prioritize explicit semantics,neglecting the potential of implicit *** paper aims to easily and effectively enhance the receiver's decoding capability without modifying the encoder and decoder *** propose a novel semantic communication system with variational neural inference for text ***,we introduce a simple but effective variational neural inferer at the receiver to infer the latent semantic information within the received *** information is then utilized to assist in the decoding *** simulation results show a significant enhancement in system performance and improved robustness.

关键词： deep learning semantic communication variational neural inference

Solar energetic particles intensity variations associated with a tilted-dipole 3D corotating interaction region

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Earth and Planetary Physics 2024年第5期8卷 797-810页

作者： YuJi Zhu Fang Shen xi Luo Yang Wang BoFeng Tang State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences Shandong Institute of Advanced Technology (SDIAT) College of Earth and Planetary sciences University of Chinese Academy of Sciences school of science Harbin Institute of Technology

The effect of a tilted-dipole three-dimensional corotating interaction region(CIR) on the transport and acceleration of solar energetic particles(SEPs) is *** this work,we discussed how the particle intensity longitudinal and radial dependence might be influenced by the background ***,we investigate how the spectral index distribution is modulated by the CIR structure We use the focused transport equation(FTE) to describe the propagation and acceleration of SEPs in a tilt-dipole 3D CIR,generated by the high-resolution 3D magnetohydrodynamic(MHD) *** forward stochastic differential method is used to solve the *** protons with theE～(-4.4)spectrum from 0.5 to 15 MeV are injected uniformly at the heliographic equator of 0.15 *** quantities are extracted along each interplanetary magnetic field(IMF) line to show the *** the tilted-dipole CIR background,if injected from the solar equator at the inner boundary,particles in the slow flow are transported to higher latitudes due to the extension of the IMF lines to higher *** longitudinal patterns of the particles are dominated by the density of IMF *** focusing effect modulates the longitudinal variation of the particle intensity and gives rise to new longitudinal intensity *** adiabatic effect largely increases the intensity fluctuation along the *** structure of the solar wind can also lead to the difference of the index α in the empirical functionI＿(max)=kR～(-α),describing the radial variation of peak intensity according to our *** the influence of the CIR structure,the index α varies from 1.9 to 3.4 at 0.3-1.0 *** variation of the solar wind speed should be considered when estimating the radial dependence of the SEP peak *** spectra indices rise near the CIR boundaries and drop near the stream interface(SI).The adiabatic effect makes the spatial variability of the spectral index *** spectral index could be sim

关键词： solar energetic particle (SEP) corotating interaction regions (CIR) magnetohydrodynamic (MHD)

Refractive index changes induced by sheet beams with various intensity distributions in LiNbO_(3):Fe crystal

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science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 399-412页

作者： ZHANG Peng1, ZHAO Jianlin1, XU Honglai1, SUN Yidong2. YANG Dexing1 & WANG Meirong1 1. Institute of Optical Information science and Technology, school of science, Northwestern Polytechnical university, xi’an 710072. china 2. school of science, xi’an jiaotong university, xi’an 71.049, china 1. Institute of Optical Information science and Technology School of Science Northwestern Polytechnical University 710072 Xi’an China 2. school of science Xi’an Jiaotong University 710049 Xi’an China

According to the Kukhtarev equations and a simplified model based on the photovoltaic charge carriers transport mechanism, the distributions of the index changes (DICs) in LiNbO3:Fe crystals induced by sheet beams with various intensity profiles are theoretically analyzed. The numerically simulated results coincide with the analytic expressions deduced from the simplified model. The DICs in a LiNbO3:Fe crystal induced by sheet beams with rectangular, Gaussian and square law profiles are measured by using the interferometric method. By employing the analytic expressions, the experimental data points are well fitted. By utilizing the angular spectrum theory and the ray equation, the uniformities of the intensity profiles of the writing beams along the propagation directions and the influences of the self-defocusing effect of the crystal are numerically simulated, respectively. The results show that the experimental results are reliable. The numerically simulated method and the analytic expressions can be both employed to predict the DICs induced by sheet beams with various light intensity profiles. Furthermore, utilizing writing beams with proper intensity profiles, any desired index distributions could be obtained.

关键词： LiNbO3:Fe crystal, light intensity profile, distribution of refractive index changes, sheet beam.

TRPC6 Knockout Alleviates Renal Fibrosis through PI3K/AKT/GSK3B Pathway

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Current Medical science 2024年第3期44卷 589-602页

作者： An-bang SUN Fang-hua LI Lin ZHU xi-xi ZENG Min ZHU Qing-hua LEI Yan-hong LIAO Department of Anatomy School of Basic MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Department of Transfusion Medicine Wuhan Hospital of Traditional Chinese and Western MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Department of Nephrology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou450052China Department of Thoracic Surgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China National Basic Medical Teaching Demonstration Center Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Key Laboratory of Neurological Diseases of Ministry of Education Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

Objective Renal fibrosis is the ultimate pathway of various forms of acute and chronic kidney ***,the knockout of transient receptor potential channel 6(TRPC6)has shown promise in alleviating renal ***,the regulatory impact of TRPC6 on renal fibrosis remains *** In vivo,TRPC6 knockout(TRPC6−/−)mice and age-matched 12. SvEv(WT)mice underwent unilateral renal ischemia-reperfusion(uIR)injury surgery on the left renal pedicle or sham *** and serum were collected on days 7,14,2.,and 2. after *** vitro,primary tubular epithelial cells(PTECs)were isolated from TRPC6−/−and WT mice,followed by treatment with transforming growth factorβ1(TGFβ1)for 72.*** anti-fibrotic effect of TRPC6−/−and the underlying mechanisms were assessed through hematoxylin-eosin staining,Masson staining,immunostaining,qRT-PCR,and Western *** Increased TRPC6 expression was observed in uIR mice and PTECs treated with TGFβ***6−/−alleviated renal fibrosis by reducing the expression of fibrotic markers(Col-1,α-SMA,and vimentin),as well as decreasing the apoptosis and inflammation of PTECs during fibrotic progression both in vivo and in ***,we found that the phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)/glycogen synthase kinase 3 beta(GSK3β)signaling pathway,a pivotal player in renal fibrosis,was down-regulated following TRPC6 *** These results suggest that the ablation of TRPC6 may mitigate renal fibrosis by inhibiting the apoptosis and inflammation of PTECs through down-regulation of the PI3K/AKT/GSK3β*** TRPC6 could be a novel therapeutic strategy for preventing chronic kidney disease.

关键词： transient receptor potential channel 6 ischemia-reperfusion injury renal fibrosis renal tubular epithelial cells

Hierarchical Controller Synthesis Under Linear Temporal Logic Specifications Using Dynamic Quantization

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IEEE/CAA Journal of Automatica Sinica 2024年第10期11卷 2082-2098页

作者： Wei Ren Zhuo-Rui Pan Weiguo xia xi-Ming Sun the Key Laboratory of Intelligent Control and Optimization for Industrial Equipment of Ministry of Education Dalian University of Technology the school of Control science and Engineering Dalian University of TechnologyDalian 116024China

Linear temporal logic(LTL)is an intuitive and expressive language to specify complex control tasks,and how to design an efficient control strategy for LTL specification is still a *** this paper,we implement the dynamic quantization technique to propose a novel hierarchical control strategy for nonlinear control systems under LTL *** on the regions of interest involved in the LTL formula,an accepting path is derived first to provide a high-level solution for the controller synthesis ***,we develop a dynamic quantization based approach to verify the realization of the accepting *** realization verification results in the necessity of the controller design and a sequence of quantization regions for the controller ***,the techniques of dynamic quantization and abstraction-based control are combined together to establish the local-to-global control *** abstraction construction and controller design are local and dynamic,thereby resulting in the potential reduction of the computational *** each quantization region can be considered locally and individually,the proposed hierarchical mechanism is more efficient and can solve much larger problems than many existing ***,the proposed control strategy is illustrated via two examples from the path planning and tracking problems of mobile robots.

关键词： Abstraction-based control design dynamic quantization formal methods linear temporal logic(LTL)