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A direct position determination method with combined TDOA and FDOA based on particle filter

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Chinese Journal of Aeronautics 2018年第1期31卷 161-168页

作者： zhiyu lu Bin BA Jianhui WANG Wenchao LI Daming WANG China National Digital Switching System Engineering & Technological R&D Cente Zhengzhou 450000 China Jiuquan Satellite Launch Center Jiuquan 735000 China

The localization of a stationary transmitter using moving receivers is considered. The original Direct Position Determination （DPD） methods, with combined Time Difference of Arrival （TDOA） and Frequency Difference of Arrival （FDOA）, do not perform well under low Signal-to-Noise Ratio （SNR）, and worse still, the computation cost is difficult to accept when the computational capabilities are limited. To get better positioning performance, we present a new DPD algorithm that proves to be more computationally efficient and more precise for weak signals than the conventional approach. The algorithm partitions the signal received with the same receiver into multiple non-overlapping short-time signal segments, and then uses the TDOA, the FDOA and the coherency among the short-time signals to locate the target. The fast maximum likelihood estimation, one iterative method based on particle filter, is designed to solve the problem of high computation load. A secondary but important result is a derivation of closed-form expressions of the Cramer-Rao Lower Bound （CRLB）. The simulation results show that the algorithm proposed in this paper outperforms the traditional DPD algorithms with more accurate results and higher computational efficiency, and especially at low SNR, it is more close to the CRLB.

关键词： Direct position determination Cramer-Rao lower bound Frequency difference of arrival Time difference of arrival Particle filter

Enhanced hydrogen storage properties of Mg by the synergistic effect of grain refinement and NiTiO_(3)nanoparticles

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Journal of Magnesium and Alloys 2022年第12期10卷 3542-3552页

作者： Nianhua Yan Xiong lu zhiyu lu Haijie Yu Fuying Wu Jiaguang Zheng Xiuzhen Wang Liuting Zhang School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang212003China Analysis and Testing Center Jiangsu University of Science and TechnologyZhenjiang212003China

As a promising hydrogen storage material,the practical application of magnesium is obstructed by the stable thermodynamics and sluggish *** this paper,three kinds of NiTiO3catalysts with different mole ratio of Ni to Ti were successfully synthesized and doped into nanocrystalline Mg to improve its hydrogen storage *** results indicated that all the Mg-NiTiO3composites showed prominent hydrogen storage ***,the Mg-NiTiO3/TiO2composite could take up hydrogen at room temperature and the apparent activation energy for hydrogen absorption was dramatically decreased from 69.8±1.2(nanocrystalline Mg)k J/mol to 34.2±0.2 k J/*** addition,the hydrogenated sample began to release hydrogen at about 193.2℃and eventually desorbed 6.6 wt%*** desorption enthalpy of the hydrogenated Mg-NiTiO3-C was estimated to be 78.6±0.8 k J/mol,5.3 k J/mol lower compared to 83.9±0.7 k J/mol of nanocrystalline ***,the sample revealed splendid cyclic stability during 20 *** obvious recession occurred in the absorption and desorption kinetics and only 0.3 wt%hydrogen capacity degradation was *** structural analysis demonstrates that nanosizing and catalyst doping led to a synergistic effect on the enhanced hydrogen storage performance of Mg-NiTiO3-C composite,which might serve as a reference for future design of highly effective hydrogen storage materials.

关键词： Hydrogen storage NiTiO3 Nanocrystalline Mg Reversibility Synergistic effect

Boosting the hydrogen storage performance of magnesium hydride with metal organic framework-derived Cobalt@Nickel oxide bimetallic catalyst

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Chinese Journal of Chemical Engineering 2022年第12期52卷 161-171页

作者： Yan Zhang Jiaguang Zheng zhiyu lu Mengchen Song Jiahuan He Fuying Wu Liuting Zhang School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China Analysis and Testing Center Jiangsu University of Science and TechnologyZhenjiang 212003China State Key Laboratory of Silicon Materials Department of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China

In this study,a MOF-derived bimetallic Co@NiO catalyst was synthesized and doped into MgH_(2)to improve the hydrogen desorption and resorption *** Co@NiO catalyst decreased the onset dehydrogenation temperature of MgH_(2)by 160℃,compared with un-doped MgH_(2).The MgH^(2+)9%(mass)Co@NiO composite released 6.6%(mass)hydrogen in 350 s at 315℃and uptook 5.4%(mass)hydrogen in500 s at 165℃,showing greatly accelerated de/rehydrogenation ***,the desorption activation energy of MgH^(2+)9%(mass)Co@NiO was decreased to(93.8±8.4)kJ·mol^(-1).Noteworthy,symbiotic Mg_(2)NiH_(4)/Mg_(2)CoH_(5)clusters were in-situ formed from bimetallic precursors and inlaid on MgH_(2)surface,which are considered as"multi-step hydrogen pumps",and provides surface pathways for hydrogen ***,the introduced Mg_(2)NiH_(4)/Mg_(2)CoH_(5)interfaces could provide numerous low energy barrier H diffusion channels,therefore accelerating the hydrogen release and *** research proposes new insights to design high-efficiency bimetallic catalyst for MgH_(2)hydrogen storage.

关键词： Hydrogen Absorption Catalyst MgH_(2) Bimetallic materials Synergistic effect

The effect of different Co phase structure(FCC/HCP)on the catalytic action towards the hydrogen storage performance of MgH_(2)

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Chinese Journal of Chemical Engineering 2022年第3期35卷 343-352页

作者： Liuting Zhang Haijie Yu zhiyu lu Changhao Zhao Jiaguang Zheng Tao Wei Fuying Wu Beibei Xiao School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China Analysis and Testing Center Jiangsu University of Science and TechnologyZhenjiang 212003China

High hydrogen desorption temperature and sluggish reaction kinetics are the major limitations for the practical application of MgH_(2).In this study,Co particles with a face centered cubic(FCC)structure and a hexagonal close packed(HCP)structure were prepared facilely and proved to be good catalysts for magnesium *** particles with FCC structure presented better catalytic effect on MgH_(2)than that with HCP *** 7%(mass)Co FCC and HCP particle modified MgH_(2)decreased the initial dehydrogenation temperature from 301.3℃ to approximately 195.0℃,but 7%(mass)Co with FCC structure modified MgH_(2)has a faster desorption rate,and around 6.5%(mass)H_(2)was desorbed in 10 min at325℃.Hydrogen uptake was detected at 70℃ under 3.25 MPa hydrogen pressure and 6.0%(mass)H_(2)was recharged in 40 min at 150℃.The hydrogen desorption and absorption activation energy for 7%(mass)FCC Co modified MgH_(2)was significantly decreased to(76.6±8.3)kJ·mol^(-1) and(68.3±6.0)kJ·mol^(-1),*** property was also studied,the plateau pressures of MgH_(2)+7%(mass)FCC Co were determined to be 0.14,0.28,0.53 and 0.98 MPa for 300℃,325℃,350℃ and375℃.The decomposition enthalpy of hydrogen(ΔH)for MgH_(2)+7%(mass)FCC Co was(80.6±0.1)kJ·mol^(-1),5.8 kJ·mol^(-1)lower than that of as-prepared MgH_(2).Moreover,cycling performance for the first20 cycles revealed that the reaction kinetics and capacity of MgH_(2)-FCC Co composite remained almost *** result of density functional theory calculation demonstrated that cobalt could extract the Mg AH bond and reduced the decompose energy of magnesium *** paper can be presented as a reference for searching highly effective catalysts for hydrogen storage and other energy-related research fields.

关键词： Hydrogen storage MgH_(2) FCC/HCP Co particles Catalysis Density functional theory

Bullet-like vanadium-based MOFs as a highly active catalyst for promoting the hydrogen storage property in MgH_(2)

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International Journal of Minerals,Metallurgy and Materials 2023年第1期30卷 44-53页

作者： zhiyu lu Jiahuan He Mengchen Song Yan Zhang Fuying Wu Jiaguang Zheng Liuting Zhang Lixin Chen School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China Instrumental Analysis Center Jiangsu University of Science and TechnologyZhenjiang 212003China State Key Laboratory of Silicon Materials Department of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China

The practical application of magnesium hydride(MgH_(2))was seriously limited by its high desorption temperature and slow desorp-tion *** this study,a bullet-like catalyst based on vanadium related MOFs(MOFs-V)was successfully synthesized and doped with MgH_(2) by ball milling to improve its hydrogen storage *** analysis demonstrated that the as-synthesized MOFs was consisted of V_(2)O_(3) with a bullet-like *** adding 7wt%MOFs-V,the initial desorption temperature of MgH_(2) was reduced from 340.0 to 190.6℃.Besides,the MgH_(2)+7wt%MOFs-V composite released 6.4wt%H_(2) within 5 min at 300℃.Hydrogen uptake was started at 60℃under 3200 kPa hydrogen pressure for the 7wt%MOFs-V containing *** desorption and absorption apparent activity energies of the MgH_(2)+7wt%MOFs-V composite were calculated to be(98.4±2.9)and(30.3±2.1)kJ·mol^(-1),much lower than(157.5±3.3)and(78.2±3.4)kJ·mol^(−1) for the as-prepared MgH_(2).The MgH_(2)+7wt%MOFs-V composite exhibited superior cyclic *** the 20 cycles isothermal dehydrogenation and hydrogenation experiments,the hydrogen storage capacity stayed almost unchanged.X-ray diffraction(XRD)and X-ray photoelectron spectrometer(XPS)measurements confirmed the presence of metallic vanadium in the MgH_(2)+7wt%MOFs-V composite,which served as catalytic unit to markedly improve the hydrogen storage properties of Mg/MgH_(2) system.

关键词： hydrogen storage magnesium hydrides vanadium based MOFs catalytic mechanism

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多观测值约束的可见光定位算法

西安电子科技大学学报 2017年第4期44卷 156-161页

作者：鲁航崔维嘉巴斌逯志宇信息工程大学信息系统工程学院河南郑州450001

在室内复杂多噪的可见光传输环境中,针对由于传统接收光强检测定位存在的建模不准确而导致定位精度低和成像定位存在的终端位置坐标与姿态角约束信息不足的问题,提出一种多观测值约束的可见光定位算法.该算法首先根据接收光强检测定位... 详细信息

在室内复杂多噪的可见光传输环境中,针对由于传统接收光强检测定位存在的建模不准确而导致定位精度低和成像定位存在的终端位置坐标与姿态角约束信息不足的问题,提出一种多观测值约束的可见光定位算法.该算法首先根据接收光强检测定位与成像定位建立联合定位状态空间模型;据此构造系统观测值与状态值,列出观测方程与状态方程;最后利用无损卡尔曼滤波算法进行求解得到定位结果.仿真实验表明,与接收光强检测定位和成像定位相比,该算法的定位结果均方误差更加逼近克拉美罗下界且可定位概率更高.

关键词：可见光室内定位系统成像传感器克拉美罗下界

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分布式信源数据域直接位置估计方法

电子与信息学报 2018年第2期40卷 371-377页

作者：王大鸣任衍青逯志宇巴斌解放军信息工程大学信息系统工程学院郑州450001

针对目前信号数据域直接位置估计方法对分布式信号源进行直接定位存在精度下降问题,该文提出分布式信源数据域直接位置估计方法。首先构建分布式信源直接位置估计模型,然后分别基于最大似然准则和特征结构分解思想给出分布式信源高精度... 详细信息

针对目前信号数据域直接位置估计方法对分布式信号源进行直接定位存在精度下降问题,该文提出分布式信源数据域直接位置估计方法。首先构建分布式信源直接位置估计模型,然后分别基于最大似然准则和特征结构分解思想给出分布式信源高精度直接位置估计的两种方法分布源最大似然估计方法和广义子空间方法。最后通过多维搜索完成对于分布式信源的直接位置估计。仿真分析表明,该文算法对分布式信源进行直接位置估计的精度较传统直接位置估计算法明显提升,能够在较低信噪比下逼近克拉美罗界;分布源最大似然估计方法在低信噪比下定位精度优于广义子空间方法,而广义子空间方法复杂度更低。

关键词：阵列信号处理直接定位分布式信源

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修正容积卡尔曼滤波数据域直接定位算法

航空学报 2018年第9期39卷 162-169页

作者：逯志宇王建辉巴斌王大鸣解放军信息工程大学信息系统工程学院郑州450000

为解决数据域直接定位(DPD)算法面临的计算压力,提高算法效率,提出一种基于修正的容积卡尔曼滤波(MCKF)的DPD算法。首先,融合各观测信号波达方向信息,利用子空间数据融合方法建立一种基于间接观测量的DPD滤波模型;然后,根据模型特点设计... 详细信息

为解决数据域直接定位(DPD)算法面临的计算压力,提高算法效率,提出一种基于修正的容积卡尔曼滤波(MCKF)的DPD算法。首先,融合各观测信号波达方向信息,利用子空间数据融合方法建立一种基于间接观测量的DPD滤波模型;然后,根据模型特点设计MCKF算法进行求解,解决间接观测量带来的噪声累积问题;最后,对算法计算量进行分析和对比,说明计算效率的提升。仿真结果表明,所提算法与基于最大似然遍历搜索和遗传算法的DPD算法相比,在相同的估计性能下,计算量下降明显,时效性显著提升,增加了算法实用价值。

关键词：直接定位容积卡尔曼滤波阵列信号处理无源定位

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基于进化粒子滤波的数据域直接跟踪方法

系统工程与电子技术 2018年第5期40卷 968-975页

作者：逯志宇巴斌任衍青王大鸣信息工程大学信息系统工程学院河南郑州450001

传统目标跟踪算法首先通过采样信号估计时延或多普勒等参数,然后利用这些参数构成的跟踪方程获得目标运动轨迹,这种两步跟踪模式存在位置信息损失、误差累积等问题,跟踪精度仍有待提高。针对此问题,提出一种利用数据域采样信号,基于时... 详细信息

传统目标跟踪算法首先通过采样信号估计时延或多普勒等参数,然后利用这些参数构成的跟踪方程获得目标运动轨迹,这种两步跟踪模式存在位置信息损失、误差累积等问题,跟踪精度仍有待提高。针对此问题,提出一种利用数据域采样信号,基于时延和多普勒信息的直接跟踪算法。该算法利用多个观测站的接收信号,首先建立一个基于连续时间和多普勒信息的直接跟踪模型;然后基于进化粒子滤波算法,对所提跟踪模型进行迭代求解,提高算法计算效率,实现对运动目标的快速高精度跟踪;最后,针对所提模型,推导了目标直接跟踪的克拉美罗下界(Cramer-Rao lower bound,CRLB)递归求解方法,给出了算法的跟踪误差下限。仿真实验表明,与现有跟踪算法相比,所提算法跟踪精度更高,收敛速度更快,尤其在低信噪比条件下更能逼近CRLB。

关键词：直接跟踪粒子滤波到达时间克拉美罗下界