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Passive IoT Localization technology Based on SD-PDOA in NLOS and Multi-Path Environments

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Computers, Materials & Continua 2024年第7期80卷 913-930页

作者： Junyang Liu Yuan Li Yulu Zhang Shuai Ma Gui Li Yi He Haiwen Yi Yue Liu Xiaotao Xu Xu Zhang Jinyao He Guangjun Wen Jian Li School of Information and Communication engineering/Yibin Institute University of Electronic Science and Technology of ChinaChengdu611731China Department of IoT technology Research China Mobile Research InstituteBeijing100053China The 10th Research Institute of China Electronics technology Group corporation Chengdu611731China College of Information and Communication National University of Defense TechnologyWuhan430019China

Addressing the challenges of passive Radio Frequency Identification(RFID)indoor localization technology in Non-Line-of-Sight(NLoS)and multipath environments,this paper presents an innovative approach by introducing a combined technology integrating an improved Kalman Filter with Space Domain Phase Difference of Arrival(SD-PDOA)and Received Signal Strength Indicator(RSSI).This methodology utilizes the distinct channel characteristics in multipath and NLoS contexts to effectively filter out interference and accurately extract localization information,thereby facilitating high precision and stability in passive RFID *** efficacy of this approach is demonstrated through detailed simulations and empirical tests conducted on a custom-built experimental platform consisting of passive RFID tags and an R420 *** findings are significant:in NLoS conditions,the four-antenna localization system achieved a notable localization accuracy of 0.25 m at a distance of 5 *** complex multipath environments,this system achieved a localization accuracy of approximately 0.5 m at a distance of 5 *** compared to conventional passive localization methods,our proposed solution exhibits a substantial improvement in indoor localization accuracy under NLoS and multipath *** research provides a robust and effective technical solution for high-precision passive indoor localization in the Internet of Things(IoT)system,marking a significant advancement in the field.

关键词： Indoor localization multipath and NLoS environments combined SD-PDOA and RSSI technology

Access to advanced sodium-ion batteries by presodiation:Principles and applications

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Journal of Energy Chemistry 2024年第5期92卷 162-175页

作者： Shihao Zhang Ruoyu Cao Xiangjun Pu Along Zhao Weihua Chen Chunhua Song Yongjin Fang Yuliang Cao College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan UniversityWuhan 430072HubeiChina College of Chemistry&Green Catalysis Center Zhengzhou UniversityZhengzhou 450001HenanChina Shenzhen Janaenergy techonulogy Co. Ltd.Shenzhen 518000GuangdongChina School of Chemistry and Chemical engineering Jiangsu University of TechnologyChangzhou 213001JiangsuChina Zonergy corporation NO.68 Fucang RoadYantan DistrictZigong 643030SichuanChina

Sodium-ion batteries(SIBs)are expected to offer affordability and high energy density for large-scale energy storage ***,the commercial application of SIBs is hurdled by low initial coulombic efficiency(ICE),continuous Na loss during long-term operation,and low sodium-content of cathode *** this scenario,presodiation strategy by introducing an external sodium reservoir has been rationally proposed,which could supplement additional sodium ions into the system and thereby markedly improve both the cycling performance and energy density of *** this review,the significance of presodiation is initially introduced,followed by comprehensive interpretation on technological properties,underlying principles,and associated approaches,as well as our perspectives on present inferiorities and future research ***,this contribution outlines a distinct pathway towards the presodiation methodology,of significance but still in its nascent phase,which may inspire the targeted guidelines to explore new chemistry in this field.

关键词： Presodiation Increased coulombic efficiency High reversible capacity Sodium ion batteries

Diffusion-Free All-Solid-State Batteries Enabled by an Ionic/Electronic Dual-Conductive Anode

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Renewables 2024年第3期2卷 194-203页

作者： Yue Ji Zaifa Wang Changtai Zhao Zhiqiang Fang Yue Gong Qihang Jing Yu Xia Tengjiao Luan Yingying Jiang Jianwen Liang Xiaona Li Mengdi Zhao Ximin Zhai Xiaofei Bie Tao Jiang Dongsheng Geng Xueliang Sun School of Materials Science and engineering University of Science and Technology BeijingBeijing 100083 Solid State Batteries Research Center GRINM(Guangdong)Institute for Advanced Materials and TechnologyFoshan 528051 China Automotive Battery Research Institute Co.Ltd. Beijing 100088 China FAW corporation Limited Changchun 130013 Key Laboratory of Automobile Materials of Ministry of Education&School of Materials Science and engineering Jilin UniversityChangchun 130025 Eastern Institute for Advanced Study Eastern Institute of TechnologyNingbo 315200 School of Chemistry and Materials Science Nanjing University of Information Science&TechnologyNanjing 210044

Silicon(Si)is one of the most promising anodes for enabling all-solid-state batteries(ASSBs)with high energy density and ***,the tremendous volume change and sluggish kinetics result in poor electrochemical ***,we proposed an ionic/electronic dual-conductive material of Li_(x)Si as a diffusion-rapid and all-active anode for *** with pure Si anode,the as-fabricated Li_(x)Si showed dramatic promotions of 35 times electronic and 400 times ionic *** three-dimensional(3D)ionic-electronic transport system of Li_(x)Si enabled rapid kinetics and uniform volume change of electrode materials in the whole electrode,corresponding to a lower volumechange *** a result,the ASSBs with LiCoO_(2)cathode exhibited a reversible discharge capacity of 154.4 mAh g−1,corresponding to an initial Coulombic efficiency of 97.3%.Besides,the batteries delivered a high rate capacity of 99.3 mAh g^(−1)at 2 C and long-term cycle stability of 94.0%after 800 cycles at 1 C,which was much better than the pure Si *** study sheds light on a new understanding of the importance of ionic conductivity for Si-based anode and might help inspire the design of advanced anode materials for ASSBs.

关键词： all-solid-state batteries lithium silicon anodes interface stability ionic-electronic conductors long-term cycling performance

The Immense Impact of Reverse Edges on Large Hierarchical Networks

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engineering 2024年第5期36卷 240-249页

作者： Haosen Cao Bin-Bin Hu Xiaoyu Mo Duxin Chen Jianxi Gao Ye Yuan Guanrong Chen Tamás Vicsek Xiaohong Guan Hai-Tao Zhang MOE engineering Research Center of Autonomous Intelligent Unmanned Systems State Key Laboratory of Intelligent Manufacturing Equipment and TechnologySchool of Artificial Intelligence and AutomationHuazhong University of Science and TechnologyWuhan 430074China School of Mechanical and Aerospace engineering Nanyang Technological UniversitySingapore 639798Singapore Jiangsu Key Laboratory of Networked Collective Intelligence School of MathematicsSoutheast UniversityNanjing 210096China Department of Computer Science Rensselaer Polytechnic InstituteTroyNY 12180USA Department of Electronic engineering City University of Hong KongHong Kong 999077China Department of Biological Physics Eötvös UniversityBudapest 1117Hungary MOE Key Laboratory for Intelligent Networks and Network Security School of Automation Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China

Hierarchical networks are frequently encountered in animal groups,gene networks,and artificial engineering systems such as multiple robots,unmanned vehicle systems,smart grids,wind farm networks,and so *** structure of a large directed hierarchical network is often strongly influenced by reverse edges from lower-to higher-level nodes,such as lagging birds’howl in a flock or the opinions of lowerlevel individuals feeding back to higher-level ones in a social *** study reveals that,for most large-scale real hierarchical networks,the majority of the reverse edges do not affect the synchronization process of the entire network;the synchronization process is influenced only by a small part of these reverse edges along specific *** surprisingly,a single effective reverse edge can slow down the synchronization of a huge hierarchical network by over 60%.The effect of such edges depends not on the network size but only on the average in-degree of the involved *** overwhelming majority of active reverse edges turn out to have some kind of“bunching”effect on the information flows of hierarchical networks,which slows down synchronization *** finding refines the current understanding of the role of reverse edges in many natural,social,and engineering hierarchical networks,which might be beneficial for precisely tuning the synchronization rhythms of these *** study also proposes an effective way to attack a hierarchical network by adding a malicious reverse edge to it and provides some guidance for protecting a network by screening out the specific small proportion of vulnerable nodes.

关键词： Synchronizability Large hierarchical networks Reverse edges Information flows Complex networks

Excitation and Detection of Shear Horizontal Waves with Electromagnetic Acoustic Transducers for Nondestructive Testing of Plates

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Chinese Journal of Mechanical engineering 2014年第2期27卷 428-436页

作者： MA Qingzeng JIAO Jingpin HU Ping ZHONG Xi WU Bin HE Cunfu Electric Power Research Institute of guangdong Power Grid corporation College of Mechanical engineering and Applied Electronics technology Beijing University of Technology

The fundamental shear horizontal（SH0） wave has several unique features that are attractive for long-range nondestructive testing（NDT）. By a careful design of the geometric configuration, electromagnetic acoustic transducers（EMATs） have the capability to generate a wide range of guided wave modes, such as Lamb waves and shear-horizontal（SH） waves in plates. However, the performance of EMATs is influenced by their parameters. To evaluate the performance of periodic permanent magnet（PPM） EMATs, a distributed-line-source model is developed to calculate the angular acoustic field cross-section in the far-field. Numerical analysis is conducted to investigate the performance of such EMATs with different geometric parameters, such as period and number of magnet arrays, and inner and outer coil widths. Such parameters have a great influence on the directivity of the generated SH0 waves that arises mainly in the amplitude and width of both main and side lobes. According to the numerical analysis, these parameters are optimized to obtain better directivity. Optimized PPM EMATs are designed and used for NDT of strip plates. Experimental results show that the lateral boundary of the strip plate has no perceivable influence on SHO-wave propagation, thus validating their used in NDT. The proposed model predicts the radiation pattern ofPPM EMATs, and can be used for their parameter optimization.

关键词： electromagnetic acoustic transducers shear-horizontal waves strip plate nondestructive testing

Theory and verification of moiréfringes for x-ray three-phase grating interferometer

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Chinese Physics B 2024年第5期33卷 532-540页

作者：单雨征葛永帅杨君郭大育蔡学宝刘晓珂侯晓文郭金川 Key Laboratory of Optoelectronic Devices and Systems of the Ministry of Education Key Laboratory of Optoelectronic Devices and Systems of the Department of EducationGuangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China Research Center for Medical Artificial Intelligence Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Institute of Advanced Science Facilities Shenzhen 518107China Institute of Electronic Paper Displays South China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou 510006China College of Biophotonics South China Normal UniversityGuangzhou 510631China MinFound Medical Systems Co. Ltd.Hangzhou 310018China

Dual-phase and three-phase grating x-ray interference is a promising new technique for grating-based x-ray differential phase contrast ***-phase grating interferometers have been relatively completely studied and *** this paper,the corresponding imaging fringe formula of the three-phase grating interferometer is *** the same time,the similarities and differences between the three-phase grating interferometer and the dual-phase grating interferometer are investigated and verified,and that the three-phase grating interferometer can produce large-period moiréfringes without using the analyzing grating is demonstrated ***,a simple method of designing three-phase grating and multi-grating imaging systems from geometric optics based on the thin-lens theory of gratings is *** theoretical formulas and experimental results provide optimization tools for designing three-phase grating interferometer systems.

关键词： x-ray phase contrast phase grating moiréfringe

Preferred Orientation in Nanocomposite Permanent Magnet Materials

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Journal of Rare Earths 2006年第1期24卷 76-80页

作者：庞利佳孙光飞陈菊芳强文江黎文安张锦标 School of Materials Science and engineering University of Science and Technology Beijing Beijing 100083 China Yuhong Magnetic Powders corporation Guangdong 529100 China

Melt-spun （Nd11.4Fe82.9B5.7）0.99M1 ribbons （M = Zr, Nb, Ga, Zr＋ Ga, Nb ＋ Ga）were prepared by melt-spinning technique. Ga addition is found to be effective for the orientation of c-axis of Nd2Fe14B grains perpendicular to the ribbon plane. Better magnetic properties can be achieved by adding both the two kinds of elements Zr ＋ Ga, Nb ＋ Ga, and it is found that the preferred orientation is further improved. The alignment degree changes with ribbon thickness and is highest when ribbon thickness is 120 μm. Heat treatment can improve the texture degree, but lead to coarser grains. Cryogenic treatment is first applied for the treatment of nanocomposite Nd2Fe14B/α-Fe melt-spun ribbons. The effects on magnetic properties and texture degree of nanocomposite magnets after cryogenic treatment were studied. The result shows that cryogenic treatment is beneficial to the enhancement of texture degree of melt-spun ribbon and the grain size has no obvious change.

关键词： nanocomposite magnets preferred orientation texture alignment degree rare earths

Green Synthesis of Magnetic Adsorbent Using Groundwater Treatment Sludge for Tetracycline Adsorption

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engineering 2019年第5期5卷 880-887页

作者： Zhan Qu Yaqiong Wu Suiyi Zhu Yang Yu Mingxin Huo Leilei Zhang Jiakuan Yang Dejun Bian Yi Wang Science and technology Innovation Center for Municipal Wastewater Treatment and Water Quality Protection Northeast Normal UniversityChangchun 130117China School of Environmental Science and engineering Huazhong University of Science and TechnologyWuhan 430074China engineering Lab for Water Pollution Control and Resources Recovery Northeast Normal UniversityChangchun 130117China guangdong shouhui lantian engineering and technology corporation Guangzhou 510075China

Groundwater treatment sludge is an industrial waste that is massively produced from groundwater treatment *** methods for treatment of this sludge,such as discharge into deep wells or the sea,or disposal at landfills,are not environmentally ***,we demonstrate an alternative strategy to recycle the sludge by preparing a magnetic maghemite adsorbent via a one-step hydrothermal method with NaOH solution as the only *** this method,the weakly magnetized sludge,which contained 33.2%iron(Fe)and other impurities(e.g.,silicon(Si),aluminum(Al),and manganese(Mn)),was converted to magnetic adsorbent(MA)with the dissolution of Si/Al oxides(e.g.,quartz and albite)into the liquid *** a NaOH concentration of 2 mol L^-1,approximately 18.1%of the ferrihydrite in the Fe oxides of the sludge was converted into 11.2%maghemite and 6.9%hematite after the hydrothermal ***2(i.e.,MA produced by a 2 mol L^-1 NaOH concentration)exhibited a good magnetic response of 8.2 emu g^-1(1 emu=10^-3 A m^2),and a desirable surface site concentration of 0.75 mmol g^-*** synthesized MA2 was used to adsorb the cationic pollutant tetracycline(TC).The adsorption kinetics of TC onto MA2 fitted well with a pseudo-second-order model,and the adsorption isotherms complied well with the Langmuir *** maximum adsorption capacity of MA2 for TC was 362.3 mg g^-1,and the main mechanism for TC adsorption was cationic *** study is the first to demonstrate the preparation of an MA from recycled sludge without a reductant and/or exogenous Fe *** prepared adsorbent can be used as a low-cost adsorbent with high capacity for TC sorption in the treatment of TC-containing wastewater.

关键词： Groundwater treatment sludge Maghemite Cationic exchange Adsorption Tetracycline

One-bit splitting deceptive jamming against SAR

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Defence technology（防务技术） 2022年第10期18卷 1760-1777页

作者： Bo Zhao Lei Huang Bing Li Shi-qi Liu Wei-min Bao guangdong Key Laboratory of Intelligent Information Processing College of Information EngineeringShenzhen UniversityShenzhen518060China China Aerospace Science and technology corporation Beijing100048China

One-bit quantization is a promising technique due to its performance retention and complexity reduction in a deceptive jammer against synthetic aperture radar(SAR).In this paper,the 1-bit quantization technology is utilized to agilely generate split false targets in the SAR imagery once the radar signal is intercepted,which reduces the complexity of the jammer significantly with guaranteed focusing quality.A single-frequency threshold is used to decompose harmonics incurred by the 1-bit quantization,and its parameters are adjusted through different pulse repetition intervals to provide steerable *** this way,the SAR signal is split into coupled false scatterers during the 1-bit *** further deploying amplitude,time-delay,and Doppler frequency modulations on the 1-bit intercepted signal,the split false targets are *** proposed approach is compared with different deceptive jamming methods to show its validity in effectiveness and cost,and numerical experiments are also presented for verification.

关键词： Synthetic aperture radar(SAR) 1-Bit quantization Multi-false-target Single-frequency threshold