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Vision-Based Adaptive Prescribed-Time Control of UAV for Uncooperative Target Tracking with Performance Constraint

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Journal of Systems Science & Complexity 2024年第5期37卷 1956-1977页

作者： SHE Xuehua MA Hui REN Hongru LI Hongyi School of Automation and the Guangdong Provincial key laboratory of Intelligent Decision and Cooperative Control Guangdong University of TechnologyGuangzhou 510006China School of Mathematics and Statistics Guangdong University of TechnologyGuangzhou 510006China College of electronic and information Engineering and Chongqing key laboratory of Generic Technology and System of Service Robots Southwest UniversityChongqing 400715China

This paper discusses the uncooperative target tracking control problem for the unmanned aerial vehicle(UAV)under the performance constraint and scaled relative velocity constraint,in which the states of the uncooperative target can only be estimated through a vision *** the limited detection range,a prescribed performance function is designed to ensure the transient and steady-state performances of the tracking ***,the scaled relative velocity constraint in the dynamic phase is taken into account,and a time-varying nonlinear transformation is used to solve the constraint problem,which not only overcomes the feasibility condition but also fails to violate the constraint ***,the practically prescribed-time stability technique is incorporated into the controller design procedure to guarantee that all signals within the closed-loop system are *** is proved that the UAV can follow the uncooperative target at the desired relative position within a prescribed time,thereby improving the applicability of the vision-based tracking *** results have been presented to prove the validity of the proposed control strategy.

关键词： Nonlinear transformation performance constraint prescribed-time tracking uncooperative target vision-based measurement

Mechanism of the electromagnetic force to control hydrodynamic noise from an airfoil model and its action mode

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Chinese Journal of Acoustics 2024年第2期43卷 173-198页

作者： LIU Yongwei WANG Lu QIN Qikai ZHENG Penghui SHANG Dejiang National key laboratory of Underwater Acoustic Technology Harbin Engineering UniversityHarbin 150001 key laboratory of Marine information acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001 College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001

A method is proposed to control the flow and reduce the hydrodynamic noise by applying the constant electromagnetic force into the boundary layer. The flow and sound fields from an airfoil model with and without the electromagnetic force are calculated. Results show that along the flow direction, electromagnetic force can delay the flow separation on the airfoil surface, suppress small discrete vortices, reduce turbulent fluctuation pressure on the airfoil surface, and decrease the hydrodynamic noise. The change law of the hydrodynamic noise effect reduced by the electromagnetic force is summarized in terms of the Reynolds number, attack angle, and electromagnetic effective *** on the numerical calculation results, an actual model is experimentally measured in the water circulating tank to validate the abovementioned effect. Since the transition area pressure of the airfoil model is the lowest and the area is limited, the application of electromagnetic force into this area can achieve the lowest noise effect and decrease the power consumption. The effect of the magnetic leak is analyzed. The results provide a new method for the suppression of hydrodynamic noise in airfoil models.

关键词： airfoil noise flow

Effects of diamagnetic drift on nonlinear interaction between multi-helicity neoclassical tearing modes

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Chinese Physics B 2024年第6期33卷 452-458页

作者：王海源姜帅刘桐魏来栾其斌王正汹 key laboratory of Materials Modification by Laser Ionand Electron Beams of the Ministry of EducationSchool of PhysicsDalian University of TechnologyDalian 116024China Faculty of electronic information and Electrical Engineering Dalian University of TechnologyDalian 116024China

A numerical study of the diamagnetic drift effect on the nonlinear interaction between multi-helicity neoclassical tearing modes(NTMs) is carried out using a set of four-field equations including two-fluid *** results show that,in contrast to the single-fluid case,5/3 NTM cannot be completely suppressed by 3/2 NTM with diamagnetic drift *** modes exhibit oscillation and coexist in the saturated *** better understand the effect of the diamagnetic drift flow on multiple-helicity NTMs,the influence of typical relevant parameters is *** is found that the average saturated magnetic island width increases with increasing bootstrap current fraction f_(b) but decreases with the ion skin depth δ.In addition,as the ratio of parallel to perpendicular transport coefficients χ_(‖)/χ_(⊥) increases,the average saturated magnetic island widths of the 3/2 and 5/3 NTMs *** underlying mechanisms behind these observations are discussed in detail.

关键词： tokamak two-fluid neoclassical tearing modes multi-helicity

Zincophilic Ti_(3)C_(2)Cl_(2)MXene and anti-corrosive Cu NPs for synergistically regulated deposition of dendrite-free Zn metal anode

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Journal of Materials Science & Technology 2024年第2期169卷 137-147页

作者： Yunfei Shen Yi Liu Kaisheng Sun Tiantian Gu Gang Wang Yue Yang Jianxiang Pang Yang Zheng Xiaodong Yang Long Chen key laboratory for Green Process of Chemical Engineering of Xinjiang Bingtuan School of Chemistry and Chemical EngineeringShihezi UniversityShihezi 832003China Institute for Chemistry Chemnitz University of TechnologyChemnitz 09107Germany CAS key laboratory of Functional Materials and Devices for Special Environments Xinjiang Key Laboratory of Electronic Information Materials and DevicesCenter of Materials Science and Optoelectronics EngineeringXinjiang Technical Institute of Physics and Chemistry of CASUrumqi 830011China key laboratory of Ecophysics and Department of Physics College of ScienceShihezi UniversityShihezi 832003China

Dendrites growth,chemical corrosion,and hydrogen evolution reaction(HER)on zinc anodes are the main barriers for the development of aqueous zinc-ion batteries(AZIBs).Constructing interfacial protec-tive layer is an effective way to alleviate the side reactions on the ***,Cu/Ti_(3)C_(2)Cl_(2)MXene(CMX)with high zincophilic and hydrophobic property is prepared by the lewis molten salts etching method,and the CMX interface protection layer is constructed by a simple spin *** CMX coat-ing layer can provide abundant nucleation sites and uniformize the charge distribution through the zin-cophilic Ti_(3)C_(2)Cl_(2)MXene matrix,leading to homogenous Zn *** addition,the hydrophobic coat-ing contained anti-corrosive Cu nanoparticles can prevent the Zn anode from the electrolyte,beneficial for suppressing the chemical corrosion and ***,the stable and reversible Zn plating/stripping is achieved for the Zn anode coated by the CMX,which exhibits the lifespan of over 1400 h at 0.5 mA cm^(−2),and even can steadily run for 700 h with 65 mV at 10 mA cm^(−2).Furthermore,CMX@Zn shows a high coulombic efficiency of over 100%for 3800 cycles,which indicates that the CMX@Zn electrode has excellent stability and reversibility of Zn stripping/*** full batteries assembled with ZnCoMnO/C(ZCM)cathodes also exhibits higher capacity(450.6 mAh g^(−1)at 0.1 A g^(−1))and cycle stability(capacity retention of 70%after 1500 cycles).This work enhanced the lifespan of AZIBs and broaden the research of multifunctional coating layer to other secondary batteries based on metal anodes.

关键词： Zinc anode Spin coating Zincophilic MXene Anti-corrosive Cu NPs Multifunctional coating

Longitudinal transducer driven by NiMnGa magnetic shape memory alloy

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Chinese Journal of Acoustics 2024年第2期43卷 232-247页

作者： LAN Yu WANG Houqi LU Wei National key laboratory of Underwater Acoustic Technology Harbin Engineering UniversityHarbin 150001 key laboratory of Marine information acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001 College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001

In order to realize a low-frequency and small-size underwater acoustic source,an underwater acoustic transducer has been designed by using Ni Mn Ga alloy, which has the advantages of large strain, rapid response and high energy density. Based on the deformation principle of Ni Mn Ga alloy, a physical model of a Ni Mn Ga longitudinal transducer is established, and the equivalentcircuit of the transducer is derived.A multi-physics coupling model of electromagnetic, mechanical and acoustic fields is established by using the finite element method to predict the underwater acoustic performance of the transducer.A small-scale prototype of the Ni Mn Ga longitudinal transducer is fabricated and its sound source level is tested in water within the frequency range from 500 Hz to 800 Hz. Experimental results demonstrate that the Ni Mn Ga transducer with an 8 mm diameter of the radiation surface, achieves sound source level of 115.5 d B at 700 Hz.

关键词： alloy NiMnGa density

Suspended nanomembrane silicon photonic integrated circuits

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Chip 2024年第3期3卷 29-35页

作者： Rongxiang Guo Qiyue Lang Zunyue Zhang Haofeng Hu Tiegen Liu Jiaqi Wang Zhenzhou Cheng School of Precision Instrument and opto-electronics Engineering Tianjin UniversityTianjin 300072China key laboratory of opto-electronic information Technology Ministry of EducationTianjin 300072China College of Physics and optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Georgia Tech-Shenzhen Institute Tianjin UniversityShenzhen 518055China Department of Chemistry The University of TokyoTokyo 113-0033Japan School of Physics and electronic Engineering Xinjiang Normal UniversityUrumqi 830054China

Leveraging the low linear and nonlinear absorption loss of silicon at mid-infrared(mid-IR)wavelengths,silicon photonic integrated circuits(PICs)have attracted significant attention for mid-IR applications including optical sensing,spectroscopy,and nonlinear ***,mid-IR silicon PICs typically show moderate performance compared to state-of-the-art silicon photonic devices operating in the telecommunication ***,we proposed and demonstrated suspended nanomembrane silicon(SNS)PICs with light-guiding within deep-subwavelength waveguide thickness for operation in the short-wavelength mid-IR *** demonstrated key building components,namely,grating couplers,waveguide arrays,micro-resonators,etc.,which exhibit excellent performances in bandwidths,back reflections,quality factors,and fabrication ***,the results show that the proposed SNS PICs have high compatibility with the multi-project wafer foundry *** study provides an unprecedented platform for mid-IR integrated photonics and applications.

关键词： Silicon photonics Suspended waveguide Mid-infrared Photonic integrated circuits Subwavelength grating

50-110 GHz,high isolation,and high-power linearity single-pole double-throw switch utilizing 100-nm GaN HEMT technology

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 38-43,71页

作者： Han Qunfei Hu Sanming Zhang Tianyu Chen Qing Shen Yizhu Wang Weibo Tao Hongqi School of information Science and Engineering Southeast UniversityNanjing 210096China Nanjing electronic Devices Institute Nanjing 210016China State key laboratory of Millimeter Waves Southeast UniversityNanjing 210096China

This article presents the design and performance of a single-pole double-throw(SPDT)switch operating in 50-110 *** switch is fabricated in a 100-nm GaN high-electron-mobility transistors(HEMT)*** realize high-power capability,the dimensions of GaN HEMTs are selected by simulation *** enhance the isolation,an improved structure of shunt HEMT with two ground holes is *** extend the operation bandwidth,the SPDT switch with multi-section resonant units is proposed and *** verify the SPDT switch design,a prototype operating in 50-110 GHz is *** measured results show that the fabricated SPDT switch monolithic microwave integrated circuit(MMIC)achieves an input 1 dB compression point(P_(1dB))of 38 dBm at 94 GHz,and isolation within the range of 33 dB to 54 dB in 50-110 *** insertion loss of the switch is less than 2.1 dB,while the voltage standing wave ratios(VSWR)of the input port and output port are both less than 1.8 in the operation *** on the measured results,the presented SPDT switch MMIC demonstrates high power capability and high isolation compared with other reported millimeter-wave SPDT MMIC designs.

关键词： GaN high-electron-mobility transistors(HEMT) millimeter-wave single-pole double-throw(SPDT) switch

Poly(3-hexylthio) thiophene Field-effect Transistor Device Performance: Impact of the Content of Hexylthio Side Chain on Backbone

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Chinese Journal of Polymer Science 2024年第1期42卷 14-23,I0005页

作者： Hao-Yu Liu Lian-He Han Ling-Wei Kong Li-Ping Zhu Xiao-Lan Qiao Mei-Fang Zhu State key laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China School of electronic information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Regioregular poly(3-hexylthio)thiopene(P3HTT) has emerged tremendous potential in organic electronic applications due to the strong noncovalent interactions from the sulfur atom linked to thiophene. However, P3HTT generally exhibits low charge mobility mostly due to poor solution processability attributed to dense arrangement of hexylthio side chain in polymer, which led to strong noncovalent interactions among sulfur atoms. To balance the nonvalent interaction and aggregation for P3HTT, herein, we systematically study the effect of hexylthio side chain content in polymer backbone on the structure and properties. A series of regioregular P3HTT-based homopolymers(P3HTT, P3HTT-50,P3HTT-33 and P3HTT-25) were prepared via Kumada catalyst transfer polycondensation method from a set of mono-, bi-, ter-and quarterthiophenes containing different contents of hexylthio side chain. The DFT calculation shows the planarity of polymers backbone could be improved through reducing the density of hexylthio side chain in polymer mainchain. And significant changes in their crystallinity, aggregation and optical properties were observed with the content of hexylthio side chain reducing. The P3HTT-33 displayed the highest field-effect transistor hole mobility of 2.83×10^(-2) cm^(2)·V^(-1)·s^(-1) resulting from a balance between the crystallinity and planarity. This study demonstrates modulating the content of hexylthio side chain in P3HTT is an effective strategy to optimize the opto-electronic properties of polymer obtaining excellent semiconductor device performance.

关键词： Conjugated polymer Polythiophene Noncovalent interaction Molecular aggregation Organic field-effect transistor

Progress in research on metal-based materials in stabilized Zn anodes

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Rare Metals 2024年第1期43卷 20-40页

作者： Le Li Shao-Feng Jia Ming-Hui Cao Yong-Qiang Ji Heng-Wei Qiu Dan Zhang Shaanxi key laboratory of Industrial Automation School of Mechanical EngineeringShaanxi University of TechnologyHanzhong 723001China School of electronic and information Engineering Qingdao UniversityQingdao 266071China State key laboratory for Artifcial Microstructure and Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100871China Department of Chemistry Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical BiologyTsinghua UniversityBeijing 100084China Shaanxi key laboratory of Catalysis School of Chemistry and Environment ScienceShaanxi University of TechnologyHanzhong 723001China

Aqueous zinc-ion batteries(ZIBs) combine the benefits of metallic Zn anodes with those of aqueous electrolytes and are well suited for large-scale energy storage because of their inherent high safety, cost-effectiveness, and eco-friendliness. Currently, the practical application of such batteries is hindered by the poor cycling performance of Zn anodes due to uncontrolled dendrite formation and severe side reactions, although recent reports suggest that these problems can be mitigated through the modification of Zn anodes with metal-based *** that the mechanisms of improving Zn deposition and the structural evolution of metal-based materials have not been systematically reviewed, we herein systematically overview the metal-based materials used to stabilize Zn anodes, starting with a brief summary of the anode working mechanism and the challenges faced by stabilized Zn anodes. Subsequently, the design principles of Zn anodes stabilized by metal-based materials and the related recent progress are reviewed, and the key challenges and perspectives for the future development of such Zn anodes are proposed.

关键词： Zinc-ion batteries(ZIBs) Zn anode Metalbased materials Alloying metal Stabilized Zn anodes