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Control techniques of tilt rotor unmanned aerial vehicle systems： A review

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Chinese Journal of Aeronautics 2017年第1期30卷 135-148页

作者： Liu Zhong he yuqing Yang Liying Han Jianda State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China

The tilt rotor unmanned aerial vehicle（TRUAV） exhibits special application value due to its unique rotor structure. However, varying dynamics and aerodynamic interference caused by tiltable rotors are great technical challenges and key issues for TRUAV＇s high-powered flight controls, which have attracted the attention of many researchers. This paper outlines the concept of TRUAV and some typical TRUAV platforms while focusing on control techniques. TRUAV structural features, dynamics modeling, and flight control methods are discussed, and major challenges and corresponding developmental tendencies associated with TRUAV flight control are summarized.

关键词： Aircraft structures Dynamics modeling Flight control Tilt rotors Unmanned aerial vehicle(UAV)

A new modeling scheme for powered parafoil unmanned aerial vehicle platforms: Theory and experiments

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Chinese Journal of Aeronautics 2019年第11期32卷 2466-2479页

作者： Bingbing LI yuqing he Jianda HAN Jizhong XIAO State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China University of Chinese A cademy of Sciences Beijing 100049China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110016China College of Artificial Intelligence Nankai UniversityTianjin 300350China The City College City University of New YorkNew York 10031USA

A novel framework is established for accurate modeling of Powered Parafoil Unmanned Aerial Vehicle(PPUAV). The model is developed in the following three steps: obtaining a linear dynamic model, simplifying the model structure, and estimating the model mismatch due to model variance and external disturbance factors. First, a six degree-of-freedom linear model, or the structured model, is obtained through dynamic establishment and linearization. Second, the data correlation analysis is adopted to determine the criterion for proper model complexity and to simplify the structured model. Next, an active model is established, combining the simplified model with the model mismatch estimator. An adapted Kalman filter is utilized for the real-time estimation of states and model mismatch. We finally derive a linear system model while taking into account of model variance and external disturbance. Actual flight tests verify the effectiveness of our active model in different flight scenarios.

关键词： Active model Data correlation analysis Model complexity Powered parafoil State estimation Unmanned aerial vehicle(UAV)

Simple PID Parameter Tuning Method Based on Outputs of the Closed Loop System

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Chinese Journal of Mechanical Engineering 2016年第3期29卷 465-474页

作者： HAN Jianda ZHU Zhiqiang JIANG Ziya he yuqing State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China

Most of the existing PID parameters tuning methods are only effective with pre-known accurate system models, which often require some strict identification experiments and thus infeasible for many complicated systems. Actually, in most practical engineering applications, it is desirable for the PID tuning scheme to be directly based on the input-output response of the closed-loop system. Thus, a new parameter tuning scheme for PID controllers without explicit mathematical model is developed in this paper. The paper begins with a new frequency domain properties analysis of the PID controller. After that, the definition of characteristic frequency for the PID controller is given in order to study the mathematical relationship between the PID parameters and the open-loop frequency properties of the controlled system. Then, the concepts of M-field and θ-field are introduced, which are then used to explain how the PID control parameters influence the closed-loop frequency-magnitude property and its time responses. Subsequently, the new PID parameter tuning scheme, i.e., a group of tuning rules, is proposed based on the preceding analysis. Finally, both simulations and experiments are conducted, and the results verify the feasibility and validity of the proposed methods. This research proposes a PID parameter tuning method based on outputs of the closed loop system.

关键词： PID control characteristic frequency step response frequency property

heterogeneous memory enhanced graph reasoning network for cross-modal retrieval

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Science China(Information Sciences) 2022年第7期65卷 157-169页

作者： Zhong JI Kexin CheN yuqing he Yanwei PANG Xuelong LI School of Electrical and Information Engineering Tianjin University Center for Optical Imagery Analysis and Learning Northwestern Polytechnical University

Cross-modal retrieval(CMR) aims to retrieve the instances of a specific modality that are relevant to a given query from another modality, which has drawn much attention because of its importance in bridging vision with language. A key to the success of CMR is to learn more discriminative and robust representations for both visual and textual instances to further reduce the heterogeneous discrepancy existing in different modalities. In this paper, we address this challenging issue by proposing a heterogeneous memory enhanced graph reasoning network, named HMGR, to connect the semantic correlations between vision and *** the one hand, we design a novel dual-path network architecture to generate relationship enhanced global representations by employing modality-specific graph reasoning on extracted local features for each *** this way, the topological interdependencies of both visual and textual intra-instance local fragments are fully mined to achieve a deeper semantic understanding of the relationships between them. On the other hand,we focus on utilizing inter-instance semantic correlated knowledge to enhance the discriminability of the final learned representations, which is achieved by introducing a joint heterogeneous memory network to iteratively restore both visual and textual instance-level information. Through interacting with long-term contextual multimodal knowledge, an encouraging shared latent feature space for mitigating the heterogeneous gap across different modalities can be learned. Extensive experiments under both image-text retrieval and video-text retrieval scenarios on three benchmark datasets demonstrate the effectiveness of our proposed method.

关键词： cross-modal retrieval graph reasoning memory network visual semantic embedding image-text retrieval video-text retrieval

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A review on the influence of intelligent power consumption technologies on the utilization rate of distribution network equipment

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Protection and Control of Modern Power Systems 2018年第1期3卷 192-202页

作者： yuqing he Yuehui Chen Zhiqiang Yang Hongbin he Li Liu Beijing hengtong of Polytron Technologies Inc Nongda Road No.1 Silicon Valley City No.2 building block A Room 401Beijing CityHaidian DistrictChina College of Electric and Information Engineering Hunan UniversityYuelu DistrictChangshaHunan ProvinceChina

The economy of distribution networks largely depends on the utilization rate of distribution network *** of the emerging intelligent power consumption technologies have a positive effect on equipment utilization and their use can save investment of distribution *** this paper,the influence of intelligent power consumption technologies on the utilization rate of distribution network equipment is *** evaluation methods and indexes are assessed first and then intelligent power consumption equipment with energy storage function,vehicle-to-grid(V2G)technology and time-of-use(TOU)tariff are reviewed *** is concluded that these intelligent power consumption technologies and measures have great potential to improve utilization rate of distribution network equipment because of their effective improvement to power ***,recommendations on how to utilize these intelligent power consumption technologies to improve utilization rate of distribution network equipment are proposed.

关键词： Intelligent power consumption technologies Energy storage Vehicle-to-grid Time-of-use tariff

Design,modeling,and control of morphing aircraft:A review

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Chinese Journal of Aeronautics 2022年第5期35卷 220-246页

作者： Lingling CHU Qi LI Feng GU Xintian DU yuqing he Yangchen DENG State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China University of Chinese Academy of Sciences Beijing 100049China Shenyang Aircraft Design&Research Institute Shenyang 110034China

A morphing aircraft can adapt its configuration to suit different types of tasks,which is also an important requirement of Unmanned Aerial Vehicles(UAV).The successful development of an unmanned morphing aircraft involves three steps that determine its ability and intelligent:configuration design,dynamic modeling and flight *** study conducts a comprehensive survey of morphing ***,the methods to design the configuration of a morphing aircraft are presented and ***,the nonlinear dynamic characteristics and aerodynamic interference caused by a morphing wing are ***,the dynamic modeling and flight control methods for solving the flight control problems are summarized with respect to these ***,the general as well as special challenges ahead of the development of intelligent morphing aircraft are *** findings can provide a theoretical and technical reference for designing future morphing aircraft or morphing-wing UAVs.

关键词： Aircraft design Dynamic modeling Fault tolerance Flight control Intelligent material Morphing aircraft Unmanned Aerial Vehicles(UAV)

Active model-based nonlinear system identification of quad tilt-rotor UAV with flight experiments

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Science China(Information Sciences) 2022年第8期65卷 105-119页

作者： Zhong LIU Didier TheILLIOL yuqing he Feng GU Liying YANG Jianda HAN Xi'an Modern Control Technology Research Institute State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of Sciences Institutes for Robotics and Intelligent Manufacturing Chinese Academy of Sciences College of Artificial Intelligence Nankai University Faculte des Sciences et Techniques CRAN UMR 7039CNRSUniversity of Lorraine

To propose an accurate and less complex model of a special unmanned aerial vehicle(UAV),namely tilt-rotor UAV(TRUAV), this study identifies the active model-based nonlinear system of a quadTRUAV. First, a nominal nonlinear model of the vehicle is formulated. Some unstructured nonlinearities are ignored to reduce the complexity of the model. Then, due to the unstable dynamics of the open-loop system,the format of this nominal model is considered to design an innovative smooth-switch attitude control via interconnection and damping assignment passivity-based control(IDA-PBC). Active model-based nonlinear system identification is studied for the vehicle with the designed control method and flight *** model error vector is defined and estimated by the unscented Kalman filter(UKF) to improve the accuracy of the model. The main contribution of this paper is to identify the nominal nonlinear model and to develop an active model method of the quad-TRUAV. The attitude control method with an innovative smooth-switch structure is another contribution to flight experiments. Numerical results are displayed to present the experimental results and effectiveness of the proposed nonlinear models.

关键词： tilt-rotor unmanned aerial vehicle flight control nonlinear system identification active model method unscented Kalman filter

SymTopo: An automatic tool for calculating topological properties of nonmagnetic crystalline materials

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Chinese Physics B 2019年第8期28卷 294-305页

作者： yuqing he Yi Jiang Tiantian Zhang he Huang Chen Fang Zhong Jin Computer Network Information Center Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Beijing National Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of SciencesBeijing 100190China Center of Scientific Computing Applications & Research Chinese Academy of SciencesBeijing 100190China

Topological materials have novel properties both in their bulk and boundaries,thereby attracting a wide interest in the theoretical and experimental *** recent development of the topological quantum chemistry and symmetrybased indicator theory in this field has significantly simplified the procedure for determining the topological properties of nonmagnetic crystalline ***,a large number of new topological materials have been found by scanning large crystal *** study provides details on the algorithm used in the Catalogue of Topological Electronic ***,based on the algorithm,we develop an automatic package named SymTopo,which calculates the symmetry representations of any given nonmagnetic crystalline material and predicts its topological *** package may facilitate the discovery of more topological materials in the future.

关键词： topological insulators topological semimetals topological invariants high-throughput research mode

Coordinative regulation of plants growth and development by light and circadian clock

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aBIOTECH 2021年第2期2卷 176-189页

作者： Chen Su Yan Wang Yingjun Yu yuqing he Lei Wang Key Laboratory of Plant Molecular Physiology CAS Center for Excellence in Molecular Plant SciencesInstitute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China

The circadian clock,known as an endogenous timekeeping system,can integrate various cues to regulate plant physiological functions for adapting to the changing environment and thus ensure optimal plant *** synchronization of internal clock with external environmental information needs a process termed entrainment,and light is one of the predominant entraining signals for the plant circadian *** can detect and transmit light information to the clock core oscillator through transcriptional or post-transcriptional interactions with core-clock components to sustain circadian rhythms and regulate a myriad of downstream responses,including photomorphogenesis and photoperiodic flowering which are key links in the process of growth and *** we summarize the current understanding of the molecular network of the circadian clock and how light information is integrated into the circadian system,especially focus on how the circadian clock and light signals coordinately regulate the common downstream *** discuss the functions of the clock and light signals in regulating photoperiodic flowering among various crop species.

关键词： Circadian clock Light signaling Photomorphogenesis Flowering time