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Particle filtering based channel estimation in OFDM power line communication

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The Journal of China Universities of Posts and Telecommunications 2014年第5期21卷 24-30,42页

作者： zhang Pei-ling zhang Hong-xin LIU Hong-da zhang Yu-jing HE Peng-fei PANG Xue-li School of Telecommunication Engineering Beijing University of Posts and Telecommunications School of Electrical Engineering and Automation Henan Polytechnic University Beijing Key Laboratory of Work Safety Intelligent Monitoring Beijing University of Posts and Telecommunications School of Opto-electronic Information Science and Technology Yantai University Nanyang Information Engineering School

Particle filtering （PF） algorithm has the powerful potential for coping with difficult non-linear and non-Gaussian problems. Aiming at non-linear, non-Gaussian and time-varying characteristics of power line channel, a time-varying channel estimation scheme combined PF algorithm with decision feedback method is proposed. In the proposed scheme, firstly the indoor power line channel is measured using the pseudo-noise （PN） correlation method, and a first-order dynamic autoregressive （AR） model is set up to describe the measured channel, then, the channel states are estimated dynamically from the received signals by exploiting the proposed scheme. Meanwhile, due to the complex noise distribution of power line channel, the performance of channel estimation based on the proposed scheme under the Middleton class A impulsive noise environment is analyzed. Comparisons are made with the channel estimation scheme respectively based on least square （LS）, Kalman filtering （KF） and the proposed algorithm. Simulation indicates that PF algorithm dealing with this power line channel estimation difficult non-linear and non-Gaussian problems performance is superior to those of LS and KF respectively, so the proposed scheme achieves higher estimation accuracy. Therefore, it is confirmed that PF algorithm has its own unique advantage for power line channel estimation.

关键词： power line communication (PLC) orthogonal frequency division multiplexing (OFDM) channel estimation PF KF

Fabrication of alginate-based microspheres with cellular structure for tuning ammonium dinitramide performance

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Defence Technology（防务技术） 2023年第10期28卷 111-120页

作者： Dun-ju Wang Xu Zhou Yao-feng Mao Xin Wang Ye-ming Huang Rui-hao Wang da-wei Zheng Co-Innovation Center for New Energetic Materials Southwest University of Science and TechnologyMianyang621010China China Academy of Engineering Physics Institute of Chemical MaterialsMianyang621900PR China

Recently,an emerging category green of energetic material ammonium dinitramide(ADN)has exhibited promising application in propellants due to its outstanding merits in energy release and environmental *** can be considered to substitute traditional oxidizer of ammonium perchlorate(AP)in military systems and *** this paper,a novel spherical energetic composite ADN/copper alginate(CA)with a microporous structure was designed and prepared by the W/O gel emulsion method,and a desirable porous microsphere structure was *** characterization techniques were used to investigate the structure and properties of ADN/CA *** results showed that ADN crystals were homogeneously encapsulated in an alginate-gel *** decomposition temperature was reduced to 151.7℃compared to ADN,while the activation energy of them was reduced from 129.73 k J/mol(ADN)to 107.50 k J/mol(ADN/CA-4).In addition,as-prepared samples had lower impact and frictional sensitivity than *** mechanism of sensitivity reduction and decomposition are also ***-volume combustion tests show that peak pressure of the ADN/CA-4 achieves 253.4 k Pa and pressurization rate of 2750.4 k Pa/***,this has a promising application in improving the combustion performance and safety performance of solid propellants.

关键词： Ammonium dinitramide Sodium alginate Microspheres High reactivity Energetic materials

Dynamic performance of linear electromagnetic actuators in a stray magnetic field:theoretical analysis and experimental verification

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Plasma Science and Technology 2022年第12期24卷 213-222页

作者： Rumeng WANG Yong YANG Shaoyu WANG ming zhang International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics State Key Laboratory of Advanced Electromagnetic Engineering and TechnologySchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074People's Republic of China

Linear electromagnetic actuators(LEAs) are widely used in tokamaks,but they are extremely sensitive to and are prone to fail in a high-strength stray magnetic field(SMF),which is usually a concomitant with *** this paper,a multi-physics coupling analysis model of LEA,including magnetic field,electric circuit and mechanical motion,is proposed,and the dynamic characteristics of LEAs in SMFs are studied in detail based on the proposed *** failure mechanism of LEAs in SMFs is revealed,and the influence of SMFs on the dynamic performance of LEAs is studied and *** is shown that the failure threshold of the LEA selected in this work under the rated condition is 27 mT and 14 mT in the positive and negative direction,*** a typical SMF of 10 mT in the negative direction,the closing time of the LEA will be extended by 40%,while its opening time will be shortened by about 10%.Experimental tests are also conducted,which verify the validity of the proposed model and the analysis *** paper provides a basis for the diamagnetic optimization design of LEA,and it is of great significance to ensure the reliable operation of the tokamak.

关键词： linear electromagnetic actuator stray magnetic field dynamic performance collision velocity

Electric field manipulation enhanced by strong spin-orbit coupling: promoting rare-earth ions as qubits

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National Science Review 2020年第10期7卷 1557-1563页

作者： Zheng Liu Ye-Xin Wang Yu-Hui Fang Si-Xue Qin Zhe-ming Wang Shang-da Jiang Song Gao Beijing National Laboratory of Molecular Science State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsBeijing Key Laboratory of Magnetoelectric Materials and Devices College of Chemistry and Molecular Engineering Peking University Department of Physics Chongqing University Beijing Academy of Quantum Information Sciences School of Chemistry and Chemical Engineering South China University of Technology

Quantum information processing based on magnetic ions has potential for applications as the ions can be modified in their electronic properties and assembled by a variety of chemical methods. For these systems to achieve individual spin addressability and high energy efficiency, we exploited the electric field as a tool to manipulate the quantum behaviours of the rare-earth ion which has strong spin-orbit coupling. A Ce:YAG single crystal was employed with considerations to the dynamics and the symmetry requirements. The Stark effect of the Ce;ion was observed and measured. When demonstrated as a quantum phase gate, the electric field manipulation exhibited high efficiency which allowed up to 57 π/2 operations before decoherence with optimized field direction. It was also utilized to carry out quantum bang-bang control, as a method of dynamic decoupling, and the refined Deutsch-Jozsa algorithm. Our experiments highlighted rare-earth ions as potentially applicable qubits because they offer enhanced spin-electric coupling which enables high-efficiency quantum manipulation.

关键词： quantum coherent manipulation spin-orbit coupling spin-electric coupling rare-earth ions qubits

Experimental Investigation of the Resistance Performance and Heave and Pitch Motions of Ice-Going Container Ship Under Pack Ice Conditions

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China Ocean Engineering 2018年第2期32卷 169-178页

作者： GUO Chun-yu XIE Chang zhang Jin-zhao WANG Shuai ZHAO da-gang College of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China Nantong COSCO KHI Ship Engineering Co.Ltd Nantong 226005China Shanghai Marine Equipment Research Institute Shanghai 200031China

In order to analyze the ice-going ship’s performance under the pack ice conditions, synthetic ice was introduced into a towing tank. A barrier using floating cylinder in the towing tank was designed to carry out the resistance experiment. The test results indicated that the encountering frequency between the ship model and the pack ice shifts towards a high-velocity point as the concentration of the pack ice increases, and this encountering frequency creates an unstable region of the resistance, and the unstable region shifts to the higher speed with the increasing concentration. The results also showed that for the same speed points, the ratio of the pack ice resistance to the open water resistance increases with the increasing concentration, and for the same concentrations, this ratio decreases as the speed increases. Motion characteristics showed that the mean value of the heave motion increases as the speed increases, and the pitch motion tends to increase with the increasing speed. In addition, the total resistance of the fullscale was predicted.

关键词： synthetic ice pack ice concentration heave pitch peak collision value

基于熵权法的生鲜农产品冷链物流发展影响因素灰色关联分析

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兰州文理学院学报（社会科学版） 2024年第4期40卷 66-71页

作者：张明军杨见青张玉婧彭会萍兰州财经大学信息工程与人工智能学院甘肃兰州730020

我国生鲜农产品冷链物流行业具有巨大的发展潜力,找出对行业有显著影响的因素并针对性地采取相应措施,有助于切实有效地促进行业发展。根据行业信息和相关文献,挑选出经济条件和行业条件下共20个因素建立影响指标体系,通过熵权法和灰色... 详细信息

我国生鲜农产品冷链物流行业具有巨大的发展潜力,找出对行业有显著影响的因素并针对性地采取相应措施,有助于切实有效地促进行业发展。根据行业信息和相关文献,挑选出经济条件和行业条件下共20个因素建立影响指标体系,通过熵权法和灰色关联分析法,对各个指标的重要程度和关联程度进行排序。结果发现冷链物流规模、冷链物流设施情况、城镇化率、农业发展水平和交通基础设施条件等指标因素与我国生鲜农产品冷链物流行业发展关系较为密切,并据此结果有针对性地为行业发展提出了相关建议。

关键词：生鲜农产品冷链物流熵权法灰色关联分析

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Automatic target tracking on multi-resolution terrain

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第7期7卷 1275-1281页

作者： WAN ming zhang Wei MURRAY Marie O. KAUFMAN Ariet The Boeing Company P.O. Box 3707 MC 7L-40 Seattle W.4 98124-2207 USA Department of Computer Setence and Center for Visual Computing State University of New York at Stony BrookStony Brook NY 11794-4400 USA

We propose a high-performance path planning algorithm for automatic target tracking in the applications of real-time simulation and visualization of large-scale terrain datasets, with a large number of moving objects （such as vehicles） tracking multiple moving targets. By using a modified Dijkstra＇s algorithm, an optimal path between each vehicle-target pair over a weighted grid-presented terrain is computed and updated to eliminate the problem of local minima and losing of tracking. Then, a dynamic path re-planning strategy using multi-resolution representation of a dynamic updating region is proposed to achieve high-performance by trading-off precision for efficiency, while guaranteeing accuracy. Primary experimental results showed that our algorithm successfully achieved l0 to 96 frames per second interactive path-replanning rates during a terrain simulation scenario with 10 to 100 vehicles and multiple moving targets.

关键词： Target tracking Path planning Dijkstra's algorithm Voxel-based modeling Multi-resolution terrain Real-timevisualization and simulation

Effects of Wetland Vegetation on Soil Microbial Composition:A Case Study in Tumen River Basin,Northeast China

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Chinese Geographical Science 2017年第2期27卷 239-247页

作者： QIN Lei JIANG ming TIAN Wei zhang Jian ZHU Weihong Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China Geography Department of Sciences Yanbian UniversityYanji 133002China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Natural Resources of Changbai Mountain&Functional Molecules Yanji 133002China State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration Northeast Normal UniversityChangchun 130117China

Hydrology plays a dominant role in wetland plant distribution and microbial composition, but few studies explicitly attempted to relate the linkage between wetland vegetation and microbial community. The present study consisted of five wetland plant communities along three adjacent flood gradients zones(zone 1 dominated by Carex appendiculat, zone 2 dominated by Eleocharis ovate, and zone 3 dominated by Phragmites australis/Bidens pilosa/Calamagrostis angustifolia, which formed separate, monoculture patches). Gram negative and arbuscular mycorrhizal fungal phospholipid fatty acid(PLFA) are more abundant in the site with short flooding period(zone 3) than in the site with long flooding period(zone 1), and they are also different in the P. australis, B. spilosa and C. angustifolia of zone 3. Principle Component Analysis(PCA) showed that the flooding period could explain 92.4% of variance in microbial composition. Redundancy Analysis(Rda) showed that available nitrogen(AN), total nitrogen(TN) and soil organic matter(SOM) could explain the 79.5% of variance in microbial composition among E. ovata, P. australis, B. pilosa and C. angustifolia. Results demonstrated that flooding period was the main factor in driving the microbial composition and plant-derived resources could influence soil microbial composition in the seasonally flooded zones.

关键词： plant soil feedback redundancy analysis phospholipid fatty acid (PLFA) soil property flooding period

E-commerce business model mining and prediction

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Frontiers of Information Technology & Electronic Engineering 2015年第9期16卷 707-719页

作者： Zhou-zhou HE Zhong-fei zhang Chun-ming CHEN Zheng-gang WANG Department of Information Science and Electronic Engineering Zhejiang University Alibaba Group

We study the problem of business model mining and prediction in the e-commerce context. Unlike most existing approaches where this is typically formulated as a regression problem or a time-series prediction problem, we take a different formulation to this problem by noting that these existing approaches fail to consider the potential relationships both among the consumers （consumer influence） and among the shops （competitions or collaborations）. Taking this observation into consideration, we propose a new method for e-commerce business model mining and prediction, called EBMM, which combines regression with community analysis. The challenge is that the links in the network are typically not directly observed, which is addressed by applying information diffusion theory through the consumer-shop network. Extensive evaluations using Alibaba Group e-commerce data demonstrate the promise and superiority of EBMM to the state-of-the-art methods in terms of business model mining and prediction.

关键词： E-commerce Business model prediction Consumer influence Social network Sales prediction