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Measurement-driven Gauss-Hermite particle filter with soft spatiotemporal constraints for multi-optical theodolites target tracking

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Chinese Journal of Aeronautics 2023年第8期36卷 313-330页

作者： hongwei zhang Pengfei LI School of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518071China Army Academy of Artillery and Air Defense Zhengzhou Campus Zhengzhou 450007China

Multi-Optical Theodolite Tracking systems(MOTTs)can stealthily extract the target’s status information from bearings only through non-contact *** constrained MOTTs are partially compatible,yet many existing research works and results are based on the known model,ignoring its discrimination with the target maneuvering behavior *** compensate for these mismatches,this paper develops a Measurement-driven Gauss-Hermite Particle Filter(MGHPF),which elegantly fuses the spatiotemporal constraints and its soft form to perform MOTT ***,the target dynamic model and tracking algorithm are based on the target behavior pattern with the adaptive turn rate,fully exploiting the spatial epipolar geometry characteristics for each intersection measurement by a minimax ***,the center of the feasible area is approximated via the analytic coordinate transformation,and the latent samples are updated via the deterministic Gauss-Hermite integral method with the target’s predictive turn ***,the effects of truncation correction and compensation feedback from the current measurement and historical estimation data are adaptively incorporated into the PF’s importance distribution to cover the mixture ***,an effective causality-invariant updating rule is provided to estimate the parameters of these soft spatiotemporal constrained MOTTs with convergence *** and measured results show good agreement;compared with the stateof-the-art Multi-Model Rao-Blackwell Particle Filter(MMRBPF),the proposed MGHPF improves the filtering accuracy by 7.4%-34.7%and significantly reduces the computational load.

关键词： Causality-invariant Measurement-drivenGauss-HermiteParticleFilter(MGHPF) Multi-optical theodolite tracking system Soft spatiotemporal con-straints Targetmaneuvering behavior

Constrained auxiliary particle filtering for bearings-only maneuvering target tracking

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Journal of Systems Engineering and Electronics 2019年第4期30卷 684-695页

作者： zhang hongwei XIE Weixin Automatic Target Recognition Key Laboratory Shenzhen University

To track the nonlinear,non-Gaussian bearings-only maneuvering target accurately online,the constrained auxiliary particle filtering(CAPF)algorithm is *** restrict the samples into the feasible area,the soft measurement constraints are implemented into the update routine via the1 ***,to enhance the sampling diversity and efficiency,the target kinetic features and the latest observations are involved into the *** take advantage of the past and the current measurement information simultaneously,the sub-optimal importance distribution is constructed as a Gaussian mixture consisting of the original and modified priors with the fuzzy weighted *** a result,the corresponding weights are more evenly distributed,and the posterior distribution of interest is approximated well with a heavier *** results demonstrate the validity and superiority of the CAPF algorithm in terms of efficiency and robustness.

关键词： bearings-only maneuvering target tracking soft measurement constraints constrained auxiliary particle filtering(CAPF)

Dynamic Characteristic Analysis and Experiment for Integral Impeller Based on Cyclic Symmetry Analysis Method

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Chinese Journal of Aeronautics 2012年第5期25卷 804-810页

作者： WU Qiong zhang Yidu zhang hongwei State Key Laboratory of Virtual Reality Technology and Systems School of Mechanical Engineering and AutomationBeihang UniversityBeijing 100191China

A cyclic symmetry analysis method is proposed for analyzing the dynamic characteristic problems of thin walled integral im- peller. Reliability and feasibility of the present method are investigated by means of simulation and experiment. The fundamental cyclic symmetry equations and the solutions of these equations are derived for the cyclic symmetry structure. The computational efficiency analysis between whole and part is performed. Comparison of results obtained by the finite element analysis （FEA） and experiment shows that the local dynamic characteristic of integral impeller has consistency with the single cyclic symmetry blade. When the integral impeller is constrained and the thin walled blade becomes a concerned object in analysis, the dynamic characteristic of integral impeller can be replaced by the cyclic symmetry blade approximately. Hence, a cyclic symmetry analy- sis method is effectively used to improve efficiency and obtain more information of parameters for dynamic characteristic of integral impellers.

关键词： dynamic characteristic cyclic symmetry impellers simulation finite element analysis blade

Experimental Analysis of Link Estimation Methods in Low Power Wireless Networks

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Tsinghua Science and Technology 2011年第5期16卷 539-552页

作者： hongwei zhang Department of Computer Science Wayne State University Detroit MI 48202 USA

Wireless sensor networks are envisioned to be an integral part of cyber-physical systems, yet wireless networks are inherently dynamic and come with various uncertainties. One such uncertainty is wireless communication itself which assumes complex spatial and temporal dynamics. For dependable and predictable performance, therefore, link estimation has become a basic element of wireless network routing. Several approaches using broadcast beacons and/or unicast MAC feedback have been proposed in the past years, but there is still no systematic characterization of the drawbacks and sources of errors in bea- con-based link estimation in low-power wireless networks, which leads to ad hoc usage of beacons in rout- ing. Using a testbed of 98 XSM motes （an enhanced version of MICA2 motes）, we characterize the negative impact that link layer retransmission and traffic-induced interference have on the accuracy of beacon-based link estimation, and we show that data-driven link estimation and routing achieve higher event reliability （e.g. by up to 18.75%） and transmission efficiency （e.g., by up to a factor of 1.96） than beacon-based approaches These findings provide solid evidence for the necessity of data-driven link estimation and demonstrate the importance of addressing the drawbacks of beacon-based link estimation when designing protocols for low-power wireless networks of cyber-physical systems.

关键词： low-power wireless networks sensor networks link estimation and routing data-driven beacon-based

Effects of Machine Tool Configuration on Its Dynamics Based on Orthogonal Experiment Method

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Chinese Journal of Aeronautics 2012年第2期25卷 285-291页

作者： GAO Xiangsheng zhang Yidu zhang hongwei WU Qiong State Key Laboratory of Virtual Reality Technology and Systems Beihang University Beijing 100191 China School of Mechanical Engineering Beijing Institute of Petrochemical Technology Beijing 102617 China

In order to analyze the influence of configuration parameters on dynamic characteristics of machine tools in the working space, the configuration parameters have been suggested based on the orthogonal experiment method. Dynamic analysis of a milling machine, which is newly designed for producing turbine blades, has been conducted by utilizing the modal synthesis method. The finite element model is verified and updated by experimental modal analysis （EMA） of the machine tool. The result gained by modal synthesis method is compared with whole-model finite element method （FEM） result as well. According to the orthogonal experiment method, four configuration parameters of machine tool are considered as four factors for dynamic characteristics. The influence of configuration parameters on the first three natural frequencies is obtained by range analysis. It is pointed out that configuration parameter is the most important factor affecting the fundamental frequency of machine tools, and configuration parameter has less effect on lower-order modes of the system than others. The combination of configuration parameters which makes the fundamental frequency reach the maximum value is provided. Through demonstration, the conclusion can be drawn that the influence of configuration parameters on the natural frequencies of machine tools can be analyzed explicitly by the orthogonal experiment method, which offers a new method for estimating the dynamic characteristics of machine tools.

关键词： configuration parameter dynamic characteristics modal synthesis method substructure orthogonal experiment method

Layered carbon-based pseudocapacitive materials for lithium/sodium-ion capacitor with high energy-power densities and long cycle life

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Progress in Natural Science:Materials International 2020年第1期30卷 20-27页

作者： Mingxiang Hu hongwei zhang Ruitao Lv State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua University Key Laboratory of Advanced Materials (MOE) School of Materials Science and EngineeringTsinghua University

Hybrid ion capacitors that combined high-power density of supercapacitor and high-energy density of battery are drawing attention to insufficient power densities of currently-used lithium-ion batteries（LIBs）.Two kinds of layered carbon-based pseudocapacitive materials were used as both anode and cathode for lithium/sodium ion capacitors（LICs/NICs） with balanced energy/power ***-assembled NIC and LIC could deliver the energy densities of 125.7 Wh kg;and 119.6 Wh kg;at the power density of 7941.2 W kg;and 8823.5 W kg;,*** electrochemical properties of NICs were better than that of LICs when the current density was below 4 A g;although the working voltage of LIC is higher than that of NICs,and the size of Na;is larger than that of Li;.Using an instantaneous potential technique,it is found that the increase of the capacity for anode material in low potential region will effectively enhance the electrochemical performance for the full device.

关键词： Sodium/lithium-ion capacitors High energy-power density Pseudocapacitive electrodes Layered materials

Application of system identification in a practical active noise control system

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Control Theory and Technology 2024年第2期22卷 282-291页

作者： Yu Yuan Zhaoyang Sun hongwei zhang School of Mechanical Engineering Xihua UniversityChengdu610039SichuanChina School of Electrical Engineering Southwest Jiaotong UniversityChengdu611756SichuanChina School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhen518055GuangdongChina

Noise pollution has become increasingly severe around the world due to fast urbanization. How to soundproof windows from outside noise is of significant interest for both academia and industry. This paper reports an experimental implementation of normalized minmax active noise control (ANC) algorithm on an open window system, where identifying the model of acoustic sound paths plays a central role. By doing this, traffic noise is attenuated by the ANC system, leading to a relatively quiet indoor environment, while the natural lighting and ventilation functions of a window are remained. Our experiments show that an average of 19 dB(A) noise reduction is achieved.

关键词： Active noise control Multi-input-multi-output system Normalized minimax algorithm System identification

Defect engineering of two-dimensional materials for efficient electrocatalysis

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Journal of Materiomics 2018年第2期4卷 95-107页

作者： hongwei zhang Ruitao Lv State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084China Key Laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing100084China

Exploring high-activity and earth-abundant electrocatalysts for electrochemical reactions,including the hydrogen evolution reaction(HER),oxygen reduction reaction(ORR)and oxygen evolution reaction(OER),*** crucial for building future large-scale green energy conversion and storage ***,some low-cost and resourceful two-dimensional(2D)semiconductor materials such as transition metal dichalcogenides(TMDCs)and layered oxides,have attracted increasing attention in electrocatalysis applications in virtue of their comparable catalytic activity and long-term stability to conventional noble metal-based catalysts(***/C,RuO_(2),IrO_(2),etc.).However,the intrinsic activity of some 2D materials still cannot meet the increasing requirement for highly efficient and reliable eletrocatalysts for future energy conversion and storage *** this context,designing elctrocatalysts with sufficient amount of active sites accessible for electrolyte,high activity of each active sites,and excellent conductivity is of great *** this end,defect engineering is a powerful strategy for tailoring the physical and chemical properties of 2D materials for efficient *** this article,an overview of recent progress on defect engineering in 2D eletrocatalysts for HER,ORR and OER is *** effects of defects on the structure and tuned properties of 2D materials in eletrocatalysts applications are also ***,the challenges and opportunities ahead in this emerging field are also proposed.

关键词： Defect engineering 2D materials HER ORR OER

Aeolian Activities and Protective Effects of Artificial Plants in Re-vegetated Sandy Land of Qinghai Lake,China

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Chinese Geographical Science 2020年第6期30卷 1129-1142页

作者： WU Wangyang zhang Dengshan TIAN Lihui zhang hongwei School of Earth Sciences East China University of TechnologyNanchang 330013China State Key Laboratory of Plateau Ecology and Agriculture Qinghai Academy of Agricultural ForestrySciencesQinghai UniversityXi'ning 810016China School of Geography Science State Key Laboratory of Earth Surface Processes and Resource EcologyBeijing Normal UniversityBeijing 100875China

Land desertification and aeolian activity are currently the greatest threats to alpine ecological environments and are also the primary challenges of desertification control and ecological restoration *** of sandy lands around the Qinghai Lake in China has effectively controlled the desertification of this ***,certain issues remain which challenge its overall success,including lack of diverse biological species and poor theoretical understanding of aeolian processes,such as controlling wind-sand flow in relation to complex alpine ecological ***,to help improving afforestation techniques,this research focused on Hippophae rhamnoides,Salix cheilophila,Pinus sylvestris,Populus simonii and Artemisia desertorum vegetation implanted in the mobile dunes on the eastern shore of Qinghai *** transport characteristics and annual changes to community ecological factors from 2010–2016 were monitored in comparison with uncontrolled sand *** on simultaneous observations using gradient anemometers and sand samplers,it was found that the aeolian activities exhibited the following features:1)In re-vegetated lands,the logarithmic growth of wind speed was disrupted by the wind speed amplification in the middle and high layers and wind speed reduction in the low layers,while vegetation had significant wind-breaking(>37%)and sand-fixing(>85%)effects in 2016.2)Wind speeds in re-vegetated lands and mobile dunes showed a linear correlation,especially in lower layers of *** and ***,while sand transport in re-vegetated land increased linearly or exponentially with increasing wind speed.3)The four artificial shrubs and forests had greater sand deposition with intensities of 280–860 t/(ha·yr),largely concentrated during winter and spring which accounted for 60%–85%of the annual cycle,while *** experienced significant root undercutting;and 4)Intensity of aeolian activity in re-vegetated lands,except for A

关键词： artificial vegetation protective effect wind-sand flow wind erosion intensity vegetation-soil factor