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DPD Algorithm for Moving Source Based on Doppler Frequency Shifts: Case of Known Waveforms

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Chinese Journal of Electronics 2019年第5期28卷 978-986页

作者： WANG Ding yin jiexin YU Hongyi Institute of Information System Engineering Information Engineering University

We focus on the Direct position determination(DPD) of a moving narrowband source based on Doppler frequency shifts of signals with known *** common motion models are considered: the Constant velocity(CV) model and the Constant acceleration(CA) model. The DPD cost function is obtained after some algebraic manipulations using the Maximum likelihood(ML) criterion. To develop a computationally efficient optimization algorithm, we present a preliminary mathematical result that plays a fundamental role in development of the proposed algorithm. Subsequently, a Newton iterative algorithm is tailored to the two motion models to determine the moving transmitter’s *** compared with multidimensional grid searching, the proposed algorithm is more computationally attractive without compromising its estimation *** results confirm the superiority of the proposed algorithm.

关键词： Direct position determination(DPD) Doppler frequency shifts Moving emitter Known waveforms

A two-step weighted least-squares method for joint estimation of source and sensor locations: A general framework

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Chinese Journal of Aeronautics 2019年第2期32卷 417-443页

作者： Ding WANG jiexin yin Tao TANG Ruirui LIU Zhidong WU National Digital Switching System Engineering and Technology Research Center Zhengzhou Institute of Information Science and Technology

It is well known that the Two-step Weighted Least-Squares(TWLS) is a widely used method for source localization and sensor position refinement. For this reason, we propose a unified framework of the TWLS method for joint estimation of multiple disjoint sources and sensor locations in this paper. Unlike some existing works, the presented method is based on more general measurement model, and therefore it can be applied to many different localization ***, it does not have the initialization and local convergence problem. The closed-form expression for the covariance matrix of the proposed TWLS estimator is also derived by exploiting the first-order perturbation analysis. Moreover, the estimation accuracy of the TWLS method is shown analytically to achieve the Cramér-Rao Bound(CRB) before the threshold effect takes place. The theoretical analysis is also performed in a common mathematical framework, rather than aiming at some specific signal metrics. Finally, two numerical experiments are performed to support the theoretical development in this paper.

关键词： Cramér-Rao Bound(CRB) Disjoint sources General framework Performance analysis Sensor position refinement Source localization Weighted least-squares

A variable structure passivity control method for elastic joint robots based on cascaded high-order state estimation

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Science China(Technological Sciences) 2024年第2期67卷 395-407页

作者： ZHANG jiexin NIE PingYun ZHANG Bo State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai200240China

Passivity-based controllers are widely used to facilitate physical interaction between humans and elastic joint robots,as they enhance the stability of the interaction ***,the joint position tracking performance can be limited by the structures of these controllers when the system is faced with uncertainties and rough high-order system state measurements(such as joint accelerations and jerks).This study presents a variable structure passivity(VSP)control method for joint position tracking of elastic joint robots,which combines the advantages of passive control and variable structure *** method ensures the tracking error converges in a finite time,even when the system faces *** method also preserves the passivity of the ***,a cascaded observer,called CHOSSO,is also proposed to accurately estimate high-order system states,relying only on position and velocity *** observer allows independent implementation of disturbance compensation in the acceleration and jerk estimation *** particular,the observer has an enhanced ability to handle fast time-varying disturbances in physical human-robot *** effectiveness of the proposed method is verified through simulations and experiments on a lower limb rehabilitation robot equipped with elastic joints.

关键词： motion control elastic joint robot finite-time convergence high-order system state estimation physical human-robot interaction

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面向非圆信号的四阶累积量直接定位方法

系统工程与电子技术 2023年第9期45卷 2690-2697页

作者：邓杰尹洁昕杨宾信息工程大学信息系统工程学院河南郑州450001 国家数字交换系统工程技术研究中心河南郑州450002

针对现有基于四阶累积量的直接定位方法阵列孔径扩展不充分以及数据冗余等问题,提出了一种针对最大非圆率信号的四阶累积量直接定位方法。基于移动阵列在多个时隙对目标观测的定位场景,该方法构造了一系列去冗余四阶累积量矩阵。结合辐... 详细信息

针对现有基于四阶累积量的直接定位方法阵列孔径扩展不充分以及数据冗余等问题,提出了一种针对最大非圆率信号的四阶累积量直接定位方法。基于移动阵列在多个时隙对目标观测的定位场景,该方法构造了一系列去冗余四阶累积量矩阵。结合辐射源信号的非圆特性,利用阵列接收数据和共轭数据来构成扩展数据模型,实现了阵列孔径扩展,使等效阵元数增加,从而提升定位性能,并通过重新构造快速提取无冗余数据,大大降低矩阵运算维度。由于结合了信号的四阶累积量与非圆特性,该算法适用于信源个数大于阵元数与阵列色噪声的复杂环境。理论分析与仿真结果表明,该算法具有计算量小、高估计精度以及高分辨率等优势,并在高信噪比条件下能够达到相应克拉美罗界。

关键词：直接定位四阶累积量最大非圆率信号移动单站

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信号传播速度未知下水下多基地声纳定位算法

兵工学报 2022年第3期43卷 637-652页

作者：范超王鼎杨宾尹洁昕郑州大学网络空间安全学院河南郑州450001 战略支援部队信息工程大学信息系统工程学院河南郑州450001 国家数字交换系统工程技术研究中心河南郑州450002

针对水下多基地声纳定位系统中声波信号传播速度未知的情况,以到达时间差为系统观测量,提出一种基于误差约束等式的联合估计声波信号传播速度和目标源位置的闭式解定位算法。算法需要分两步进行。第1步通过引入辅助变量,将非线性观测方... 详细信息

针对水下多基地声纳定位系统中声波信号传播速度未知的情况,以到达时间差为系统观测量,提出一种基于误差约束等式的联合估计声波信号传播速度和目标源位置的闭式解定位算法。算法需要分两步进行。第1步通过引入辅助变量,将非线性观测方程转化为伪线性方程进行处理,求得目标源位置以及信号传播速度的初始估计解;第2步根据初始估计解的估计误差所服从的等式约束,构造新的优化模型,再用拉格朗日乘子法进行求解。推导了算法的联合估计均方误差,从理论上证明了其可以达到相应的克拉美罗界。通过数值仿真验证了估计均方误差的理论分析,并与现有算法进行仿真比较,证明了所提算法与现有算法相比具有优越性。

关键词：多基地声纳定位信号传播速度到达时间差拉格朗日乘子法

针对超视距短波辐射源的测角与测时差协同定位方法

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中国科学：信息科学 2022年第11期52卷 1942-1973页

作者：王鼎尹洁昕朱中梁战略支援部队信息工程大学信息系统工程学院郑州450001 国家数字交换系统工程技术研究中心郑州450002 盲信号处理重点实验室成都610041

对短波超视距辐射源进行定位在国防安全领域具有重要意义.短波多站定位体制包括测角交汇定位和测时差交汇定位,它们在性能上各有优劣.为了结合这两种定位技术的优势,本文研究短波测角与测时差协同定位问题.首先,在超视距传播场景下依次... 详细信息

对短波超视距辐射源进行定位在国防安全领域具有重要意义.短波多站定位体制包括测角交汇定位和测时差交汇定位,它们在性能上各有优劣.为了结合这两种定位技术的优势,本文研究短波测角与测时差协同定位问题.首先,在超视距传播场景下依次构建二维波达方向(direction-of-arrival,DOA)和到达时差(time-difference-of-arrival,TDOA)非线性观测模型;然后,在电离层虚高先验观测误差存在下推导定位精度的克拉美罗下界(Cramér-Rao lower bound,CRLB);接着,针对超视距观测方程的强非线性特征,提出一种基于DOA/TDOA观测量的短波协同定位方法;最后,利用一阶误差分析方法证明所提方法的渐近统计最优性.该方法包含两个阶段:阶段1通过引入辅助变量并求解一元二次方程得到短波DOA伪线性观测方程,基于此构建含双重二次等式约束的优化模型,并提出一种基于矩阵QR分解的迭代优化算法,用于获得辐射源位置中间估计值;阶段2利用该估计值构建短波TDOA伪线性观测方程,并提出基于矩阵分解的迭代型约束加权最小二乘估计器,以确定最终定位结果.仿真实验结果表明,所提的协同定位方法具有较好的全局收敛性,其定位性能可达到CRLB,并能获得较高的协同增益.

关键词：无线定位短波辐射源波达方向到达时差克拉美罗下界 QR分解理论性能分析

一种基于加权多维标度分析的多个非相关源TDOA/FDOA协同定位方法

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航空学报 2023年第7期44卷 222-245页

作者：王鼎尹洁昕张欣光郑娜娥中国人民解放军战略支援部队信息工程大学信息系统工程学院郑州450001 国家数字交换系统工程技术研究中心郑州450002 北京航天长征飞行器研究所北京100076 中国人民解放军战略支援部队信息工程大学数据与目标工程学院郑州450001

时/频差定位是针对运动辐射源的一类重要无线定位体制,其定位精度受时/频差观测误差和传感器模型(包括位置和速度)先验观测误差的影响较大。为了提高在大观测误差条件下的定位性能,提出一种基于加权多维标度分析的多个非相关源TDOA/FDO... 详细信息

时/频差定位是针对运动辐射源的一类重要无线定位体制,其定位精度受时/频差观测误差和传感器模型(包括位置和速度)先验观测误差的影响较大。为了提高在大观测误差条件下的定位性能,提出一种基于加权多维标度分析的多个非相关源TDOA/FDOA协同定位方法。新方法包含2个计算阶段:阶段a利用2组多维标度分析中的标量积矩阵形成定位关系式,并进而构造加权矩阵以获得多个非相关源以及各传感器位置和速度的估计值;阶段b利用多维标度分析中引入的中间变量构建阶段a估计误差的约束优化模型,由此获得阶段a估计误差的估计值,并利用其更新阶段a的估计结果。通过一阶误差分析证明,所提方法对辐射源与传感器位置和速度的估计精度均能渐近逼近相应的克拉美罗界(CRB)。仿真实验结果验证了所提方法相比于其他时/频差定位方法的优越性。

关键词：辐射源定位协同定位到达时间差(TDOA) 到达频率差(FDOA) 加权多维标度分析理论性能分析

Wettability-driven synergistic resistance of scale and oil on robust superamphiphobic coating

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Chinese Chemical Letters 2024年第7期35卷 433-438页

作者： Yixuan Wang jiexin Li Zhihao Shang Chengcheng Feng Jianmin Gu Maosheng Ye Ran Zhao Danna Liu Jingxin Meng Shutao Wang CAS Key Laboratory of Bio-inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences(UCAS) Beijing 100049China State Key Laboratory of Metastable Materials Science and Technology(MMST) Yanshan UniversityQinhuangdao 066004China

Disgusting deposits(e.g.,scale and crude oil)in daily life and industrial production are always serious problems,posing great threats to the safety and economic ***,most of developed coatings can only conquer one part of these deposits such as superhydrophobic coatings possess antiscaling capacity but would adhere crude *** integrate scale resistance with oil repellence,we herein report a robust superamphiphobic(SAB)coating simultaneously reducing pollution of scale and oil for extended period of time(two weeks with over 98%reduction).Compared with single role of superhydrophobic and amphiphilic surfaces,the SAB coating can not only inhibit interfacial nucleation of scale but also reduce the adhesion of formed scale and polluted *** durability of the SAB coating is evaluated via mechanical tests(sandpaper abrasion,tape stripping and sand falling)and chemical corrosion(corrosive liquid immersing),revealed by sustainable high contact angles and low contact angle hysteresis of water and *** universality of this strategy can be further confirmed by adding different particles like kaolin,Al_(2)O_(3),and SiO_(2),resisting multiple types of scale(i.e.,CaSO_(4),BaSO_(4)and MgCO_(3))and oil(i.e.,glycerol,glycol,and mineral oil).Therefore,this study provides an ideal avenue for resisting scale and oil,which may be used for conquering the complexity of application environments(e.g.,oil production and transportation).

关键词： Superamphiphobic Durability Wettability Anti-scaling Oil repellence

Interface-induced polymerization strategy for constructing titanium dioxide embedded carbon porous framework with enhanced chemical immobilization towards lithium polysulfides

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Nano Research 2024年第3期17卷 1473-1481页

作者： Yue Ouyang Xiaoxiao Li jiexin Zhu Wei Zong Yuhang Dai Xuan Gao Wei Zhang Shengyuan Yang Roohollah Bagherzadeh Feili Lai Yue-E Miao Tianxi Liu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua University2999 North Renmin RoadShanghai 201620China The Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China Advanced Fibrous Materials LAB Institute for Advanced Textile Materials and Technologies(ATMT)School of Advanced Materials and ProcessesAmirkabir University of TechnologyTehran 15914Iran Christopher Ingold Laboratory Department of ChemistryUniversity College London20 Gordon StreetLondon WC1H 0AJUK Department of Chemistry KU LeuvenCelestijnenlaan 200FLeuven 3001Belgium

The shuttle effect induced by soluble lithium polysulfides(LiPSs)is known as one of the crucial issues that limit the practical applications of lithium-sulfur(Li-S)***,a titanium dioxide nanoparticle embedded in nitrogen-doped porous carbon nanofiber(TiO_(2)@NCNF)composite is constructed via an interface-induced polymerization strategy to serve as an ideal sulfur *** the protection of the nanofiber walls,the uniformly dispersed TiO_(2) nanocrystalline can act as capturing centers to constantly immobilize LiPSs towards durable sulfur ***,the mesoporous microstructure in the fibrous framework endows the TiO_(2)@NCNF host with strong physical reservation for sulfur and LiPSs,sufficient pathways for electron/ion transfer,and excellent endurance for volume *** expected,the sulfur-loaded TiO_(2)@NCNF composite electrode presents a fabulous rate performance and long cycle lifespan(capacity fading rate of 0.062%per cycle over 500 cycles)at 2.0 ***,the assembled Li-S batteries harvest superb areal capacity and cycling stability even under high sulfur loading and lean electrolyte conditions.

关键词： interface-induced polymerization electrospun porous nanofibers lithium-sulfur(Li-S)batteries high sulfur loading lithium polysulfides(LiPSs)immobilization