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考虑负载不确定的异步电机反馈线性化的最小损耗控制

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电机与控制学报 2017年第5期21卷 73-80页

作者：王爱元李健顾春阳上海电机学院电气学院上海201306

研究异步电机负载变动时基于反馈线性化的最小损耗控制的实现问题。首先分析了异步电机的损耗特性,建立了受电机温度时变参数影响小的最小损耗磁链控制模型,揭示了通过转矩的实时估计对磁链进行控制可实现最小损耗控制。应用微分几何精... 详细信息

研究异步电机负载变动时基于反馈线性化的最小损耗控制的实现问题。首先分析了异步电机的损耗特性,建立了受电机温度时变参数影响小的最小损耗磁链控制模型,揭示了通过转矩的实时估计对磁链进行控制可实现最小损耗控制。应用微分几何精确线性化的理论,建立了考虑负载转矩不确定性的异步电机反馈线性化模型,实现了转速和磁链的线性化解耦控制,电机转矩的实时估计依据参考模型在电动机反馈线性化控制中实现。异步电机的反馈线性化控制既提高了动态时的响应速度,又实现了稳态时的轻载高效率运行。合理选取控制参数,实现转速、磁链以及转矩估计的渐进收敛。仿真实验表明所提控制方法的可行性和有效性。

关键词：异步电机最小损耗反馈线性化控制参考模型转矩估计

Morphological evolution of CdS films prepared by chemical bath deposition

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Rare Metals 2013年第4期32卷 380-389页

作者： Xing-Yu Peng Hong-Wei gu Teng Zhang Fei Qu Fa-Zhu Ding Hong-Yan Wang Key Laboratory of Applied Superconductivity Institute of Electrical Engineering Chinese Academy of Sciences

In this article, the growth process of chemical bath deposited CdS films was systematically investigated. The structural, optical, and morphological properties were investigated by X-ray diffraction （XRD）, transmission electron microscope （TEM）, UV-Vis spectrophotometer, scanning electron microscope （SEM）, respectively. CdS nanocubes with size of less than 500 nm and nanocrystal-lites with diameter of less than 5 nm forming in reaction solution are observed. According to the TEM results and the SEM morphological evolution of CdS films, a crystal-lite-by-crystallite growth mechanism is proposed to eluci-date the growth process of chemical bath deposited CdS films based on the present growth mechanism.

关键词： CdS Chemical bath deposition Growthmechanism Crystallite-by-crystallite

Tea picking point detection and location based on Mask-RCNN

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Information Processing in Agriculture 2023年第2期10卷 267-275页

作者： Tao Wang Kunming Zhang Wu Zhang Ruiqing Wang Shengmin Wan Yuan Rao Zhaohui jiang Lichuan gu School of Information and Computer Science Anhui Agricultural UniversityHefei 230036China Anhui Province Key Laboratory of Smart Agricultural Technology and Equipment Anhui Agriculture UniversityHefei 230036China Institute of Intelligent Agriculture Anhui Agricultural UniversityHefei 230036China

The accurate identification,detection,and segmentation of tea buds and leaves are important factors for realizing intelligent tea picking.A tea picking point location method based on the region-based convolutional neural network(R-CNN)Mask-RCNN is proposed,and a tea bud and leaf and picking point recognition model is ***,tea buds and leaf pictures are collected in a complex environment,the Resnet50 residual network and a feature pyramid network(FPN)are used to extract bud and leaf features,and preliminary classification and preselection box regression training-performed on the feature maps through a regional proposal network(RPN).Second,the regional feature aggregation method(RoIAlign)is used to eliminate the quantization error,and the feature map of the preselected region of interest(ROI)is converted into a fixed-size feature *** output module of the model realizes the functions of classification,regression and ***,through the output mask image and the positioning algorithm the positioning of the picking points of tea buds and leaves is *** hundred tea tree bud and leaf pictures in a complex environment are selected for *** experimental results show that the average detection accuracy rate reaches 93.95%and that the recall rate reaches 92.48%.The tea picking location method presented in this paper is more versatile and robust in complex environments.

关键词： Deep learning Mask R-CNN Image processing Buds and leaves Picking points

Enhanced photo-catalytic activity of gold ion and gold modified

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Journal of Environmental Sciences 2001年第2期13卷 201-204页

作者： LI Fang-bai gu guo-bang HUANG guo-feng LI Xin-jun WAN Hong-fu guangdong Institute of Eco-Environment and Soil Science Guangzhou 510650China College of Chemical Engineering South China University of TechnologyGuangdong 510642China

The gold ion modified TiO2 was prepared by means of sol-gel whereas gold deposited TiO2 was prepared by means of photoreduction. The physical properties were influenced significantly by the presence of gold ion or gold. The enhanced photo-activity of gold modified TiO2 vas quantified in terms of methylene blue degradation. The presence of gold ion in TiO2 lattices or gold on TiO2 surface enhanced their-photo-activity. The optimum molar content of gold ion doping and gold deposition all was 0.5%. The first-order rates constants of gold modified TiO2 was more than that of pure TiO2, and decreased by increasing the content of gold ion and gold when their contents were more than 0.5%. Gold ion doped in TiO2 lattices was more effective to enhance the photo-activity than gold on TiO2 surface. Moreover, the relationship between physical properties, chemical properties and photo-activity has been discussed.

关键词： gold modification titanium dioxide photo-catalysis methylene blue

Rational design of biodegradable semiconducting polymer nanoparticles for NIR-II fluorescence imaging-guided photodynamic therapy

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Nano Research 2024年第6期17卷 5399-5408页

作者： Xuxuan gu Jinlong Shen Zhiwei Xu Wenqi Wang Ying Wu Wen Zhou Chen Xie Quli Fan State Key Laboratory of Organic Electronics and Information Displays&Institute of Advanced Materials(IAM) Nanjing University of Posts&Telecommunications9 Wenyuan RoadNanjing 210023China

Semiconducting polymer nanoparticles(SPNs)have shown great promise in second near-infrared window(NIR-II)***,the issue of long metabolic time significantly restricts the clinical application of *** this study,we rationally designed a biodegradable SPN(BSPN50)for NIR-II fluorescence imaging-guided photodynamic therapy(PDT).BSPN50 is prepared by encapsulating a biodegradable SP(BSP50)with an amphiphilic copolymer ***50 is composed of NIR-II fluorescent diketopyrrolopyrrole(DPP)segment and degradable poly(phenylenevinylene)(PPV)segment with the ratio of 50/***50 has both satisfactory degradability under myeloperoxidase(MPO)/hydrogen peroxide(H_(2)O_(2))and NIR-II fluorescence emission upon 808 nm laser ***,BSPN50 shows good photodynamic efficacy under 808 nm laser ***50 shows a faster degradation rate than BSPN100 which has no PPV segment both in vitro and in *** addition,BSPN50 can effectively diagnose tumor via NIR-II fluorescence imaging and inhibit the tumor growth by ***,our study provides a rational approach to construct biodegradable nanoplatforms for efficient tumor NIR-II phototheranostics.

关键词： near-infrared(NIR)-II fluorescence imaging semiconducting polymer nanoparticles photodynamic therapy tumor imaging

Significant Reduction of Interfacial Thermal Resistance and Phonon Scattering in Graphene/Polyimide Thermally Conductive Composite Films for Thermal Management

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Research 2021年第1期2021卷 518-530页

作者： Kunpeng Ruan yongqiang guo Chuyao Lu Xuetao Shi Tengbo Ma Yali Zhang Jie Kong Junwei gu MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Conditions Shaanxi Key Laboratory of Macromolecular Science and TechnologySchool of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072China Queen Mary University of London Engineering School Northwestern Polytechnical UniversityXi’anShaanxi 710072China

The developing flexible electronic equipment are greatly affected by the rapid accumulation of heat,which is urgent to be solved by thermally conductive polymer composite ***,the interfacial thermal resistance(ITR)and the phonon scattering at the interfaces are the main bottlenecks limiting the rapid and efficient improvement of thermal conductivity coefficients(λ)of the polymer composite ***,few researches were focused on characterizing ITR and phonon scattering in thermally conductive polymer composite *** this paper,graphene oxide(GO)was aminated(NH_(2)-GO)and reduced(NH_(2)-rGO),then NH_(2)-rGO/polyimide(NH_(2)-rGO/PI)thermally conductive composite films were *** spectroscopy was utilized to innovatively characterize phonon scattering and ITR at the interfaces in NH_(2)-rGO/PI thermally conductive composite films,revealing the interfacial thermal conduction mechanism,proving that the amination optimized the interfaces between NH_(2)-rGO and PI,reduced phonon scattering and ITR,and ultimately improved the interfacial thermal *** in-planeλ(λ∥)and through-planeλ(λ_(⊥))of 15 wt%NH_(2)-rGO/PI thermally conductive composite films at room temperature were,respectively,7.13 W/mK and 0.74 W/mK,8.2 timesλ∥(0.87 W/mK)and 3.5 timesλ_(⊥)(0.21 W/mK)of pure PI film,also significantly higher thanλ∥(5.50 W/mK)andλ_(⊥)(0.62 W/mK)of 15 wt%rGO/PI thermally conductive composite *** based on the effective medium theory model proved that ITR was reduced via the amination of *** thermal imaging and finite element simulation showed that NH_(2)-rGO/PI thermally conductive composite films obtained excellent heat dissipation and efficient thermal management capabilities on the light-emitting diodes bulbs,5G high-power chips,and other electronic equipment,which are easy to generate heat severely.

关键词： composite conductive scattering

A 0.82 μVrms ultralow 1/f noise bandgap reference for a MEMS gyroscope

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Microsystems & Nanoengineering 2023年第2期9卷 77-87页

作者： Junjun Zou Qi Wei Chunge Ju Hua Liao Haoyu gu Bowen Xing Bin Zhou Rong Zhang Department of Precision Instruments Tsinghua UniversityBejing 100084China

High-precision microelectromechanical system(MEMS)gyroscopes are significant in many *** instability(BI)is an important parameter that indicates the performance of a MEMS gyroscope and is affected by the 1/f noise of the MEMS resonator and readout *** the bandgap reference(BGR)is an important block in the readout circuit,reducing its 1/f noise is key to improving a gyroscope's *** a traditional BGR,the error amplifer is applied to provide a virtual short-circuit point,but it introduces the main low-frequency noise *** paper proposes an ultralow 1/f noise BGR by removing the error amplifer and applying an optimized circuit *** addition,a simplified but accurate noise model of the proposed BGR is obtained to optimize the BGR's output noise *** verify this design,the proposed BGR has been implemented in a 180 nm CMOS process with a chip area of 545×423μ*** experimental results show that the BGR's output integrated noise from 0.1 to 10 Hz is 0.82μV and the thermal noise is 35 nV/√***,bias stability tests of the MEMS gyroscope fabricated in our laboratory with the proposed BGR and some commercial BGRs are carried *** results show that reducing the BGR's 1/f noisecannearly linearly improvethegyroscope's Bl.

关键词： noise 1/f removing

Global Optimality for Generalized Federated Filter

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自动化学报 2009年第10期35卷 1310-1316页

作者： gu Qi-Tai FANG Jing Department of Precision Instruments and Mechanology Ts- inghua University Beijing 100084 P. R. China

Based on the matrix theory and the information sharing principle, the analytic relation among centralized Kalman filtering, decentralized filtering, and federated filtering is derived. It is proved that the global filtering of federated filters is optimal only when the dimensions of the master filter and the local filters are totally equal. If the dimensions of the master filter and the local filters are different, then only suboptimal solution can be obtained. The structure of a generalized federated filter is proposed. In terms of the information sharing principle, the information matrix of the one-step prediction state error and the one-step prediction state are reset to obtain the suboptimal solution of the global filtering. Furthermore, the suboptimal solution of the global filtering is used as observation feedback to correct the one-step prediction state and yield the optimal solution of the global filtering. The optimal feedback gain matrix is mathematically derived, so the filtering result is theoretically proved to be equivalent to the centralized Kalman filtering. The result of the simulation experiments with a dual-SINS/GPS integrated navigation system demonstrates the validity of the algorithm.

关键词：整体优化广义滤波信息分配信息融合反馈

In situ protonation in a locally flexible porous coordination polymer for enhancing proton-carrier loading and proton conductivity

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Science China Chemistry 2024年第10期67卷 3432-3437页

作者： Xianzhe Wei Jincheng Liu Yan Su Weitao Wang guixiang Wang Gen Zhang Ping Wang Cheng gu State Key Laboratory of Luminescent Materials and Devices Institute of Polymer Optoelectronic Materials and DevicesSouth China University of TechnologyGuangzhou 510640China College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education School of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing 210094China

Designing efficient proton-conductive materials is crucial in fuel ***,it remains a substantial challenge because of the issues in proton mobility,proton-carrier amount,and orientation of proton host ***,we report an in-situ protonation strategy to produce a locally flexible porous coordination polymer(PCP)to enhance the proton-carrier loading and proton *** local dipole flipping of the ligand allows effective proton exchange with low activation energy,promoting interpore proton transport through the pore apertures and pore *** protonation induces substantial charges to the frameworks and enhances the interaction with proton carriers,thereby increasing the loading of the proton *** this design strategy,the resulting PCP exhibits enhanced phosphoric acid loading and extraordinary proton conductivities under both aqueous and anhydrous conditions compared to its isoreticular analog that features rigidity without proton-exchange *** work provides a new avenue for designing proton-conductive materials that combine structural dynamics with performance merits.

关键词： porous coordination polymers in-situ protonation local flexibility proton-exchange mechanism proton conduction