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IEEE/CAA Journal of Automatica Sinica 2020年第5期7卷 1417-1424页

作者： jing cheng Li Chen School of Aerospace Engineering Tsinghua UniversityBeijing 100084China School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350116China

In this paper,the dynamic evolution for a dualarm space robot capturing a spacecraft is studied,the impact effect and the coordinated stabilization control problem for postimpact closed chain system are *** first,the pre-impact dynamic equations of open chain dual-arm space robot are established by Lagrangian approach,and the dynamic equations of a spacecraft are obtained by Newton-Euler *** on the results,with the process of integral and simplify,the response of the dual-arm space robot impacted by the spacecraft is analyzed by momentum conservation law and force transfer *** closed chain system is formed in the post-impact *** chain constraint equations are obtained by the constraints of closed-loop geometry and *** the closed chain constraint equations,the composite system dynamic equations are ***,the recurrent fuzzy neural network control scheme is designed for calm motion of unstable closed chain system with uncertain system *** order to overcome the effects of uncertain system inertial parameters,the recurrent fuzzy neural network is used to approximate the unknown part,the control method with H∞tracking *** to the Lyapunov theory,the global stability is ***,the weighted minimum-norm theory is introduced to distribute torques guarantee that cooperative operation between *** last,numerical examples simulate the response of the collision,and the efficiency of the control scheme is verified by the simulation results.

关键词： Capturing operation calm motion control closed chain system dual-arm space robot recurrent fuzzy neural network H∞tracking characteristic

Theory of ghost scattering with biphoton states

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Photonics Research 2017年第1期5卷 41-45页

作者： jing cheng Department of Physics South China University of Technology

We show how quantum entangled biphoton states can be used to realize ghost scattering, a nonlocal scheme to obtain scattering information of an unknown object through the correlation measurement of the scattering photons in two different optical paths. We present a framework to describe the biphoton ghost scattering process from the T-matrix formula of the scattering theory. We find the scattering information of a test object can be retrieved from either the test arm or the reference arm. By adjusting the biphoton states, the ghost scattering patterns may be varied from the scattering pattern of the object in the test arm to the object in the reference arm.

关键词： Theory of ghost scattering with biphoton states test

Research on data load balancing technology of massive storage systems for wearable devices

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Digital Communications and Networks 2022年第2期8卷 143-149页

作者： Shujun Liang jing cheng Jianwei Zhang Software Engineering College Zhengzhou University of Light IndustryZhengzhou450000China Engineering Training Center Zhengzhou University of Light Industry Zhengzhou450000China

Because of the limited memory of the increasing amount of information in current wearable devices,the processing capacity of the servers in the storage system can not keep up with the speed of information growth,resulting in low load balancing,long load balancing time and data processing ***,a data load balancing technology is applied to the massive storage systems of wearable devices in this *** first analyze the object-oriented load balancing method,and formally describe the dynamic load balancing issues,taking the load balancing as a mapping ***,the task of assigning each data node and the request of the corresponding data node’s actual processing capacity are *** data is allocated to the corresponding data storage node to complete the calculation of the comprehensive weight of the data storage *** to the load information of each data storage node collected by the scheduler in the storage system,the load weight of the current data storage node is calculated and *** data load balancing of the massive storage system for wearable devices is *** experimental results show that the average time of load balancing using this method is 1.75h,which is much lower than the traditional *** results show the data load balancing technology of the massive storage system of wearable devices has the advantages of short data load balancing time,high load balancing,strong data processing capability,short processing time and obvious application.

关键词： Wearable device Massive data Data storage system Load balancing Weigh

A MySQL-Based Software System of Urban Land Planning Database of Shanghai in China

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Computer Modeling in Engineering & Sciences 2023年第6期135卷 2387-2405页

作者： Pei Yin jing cheng Department of Civil Engineering School of Mechanics and Engineering ScienceShanghai UniversityShanghai200444China College of Civil and Transportation Engineering Shenzhen UniversityShenzhen518057China

With the development of the digital city,data and data analysis have become more and more *** database is the foundation of data *** this paper,the software system of the urban land planning database of Shanghai in China is developed based on *** conceptual model of the urban land planning database is proposed,and the entities,attributes and connections of this model are *** the E-R conceptual model is transformed into a logical structure,which is supported by the relational databasemanagement system(DBMS).Based on the conceptual and logical structures,by using Spring Boot as the back-end framework and using MySQL and Java API as the development tools,a platformwith datamanagement,information sharing,map assistance and other functions is *** functionalmodules in this platformare *** results of J Meter test show that the DBMS can add,store and retrieve information data stably,and it has the advantages of fast response and low error *** software system of the urban land planning database developed in this paper can improve the efficiency of storing and managing land data,eliminating redundant data and sharing data.

关键词： Software database database management system urban land planning MySQL

Lensless Ghost Diffraction with Partially Coherent Sources: Effects of the Source Size, Transverse Coherence, Detector Size and Defocusing Length

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Chinese Physics Letters 2011年第9期28卷 132-135页

作者： LIN Jie cheng jing School of Electronics and Information Engineering South China University of TechnologyGuangzhou 510641 School of Physics and Optoelectronic Engineering Guangdong University of TechnologyGuangzhou 510006 Department of Physics South China University of TechnologyGuangzhou 510641

Lensless ghost diffraction with partially coherent sources is investigated theoretically and *** on the classical optical coherent theory and the Gauss–Shell model of the partially coherent sources,we derive an analytical imaging formula of lensless ghost diffraction(LGD).Using this formula,we can see the effects of the transverse size and coherence of the sources,the detector size and defocusing length on the quality of *** results are presented to show that for different detector sizes and defocusing lengths,high quality LGD can be realized by using sources with appropriate transverse sizes and coherent *** findings can be used to choose the optimal parameters in the design of a realistic LGD system.

关键词： ghost Ghost coherent

Room-temperature ferrimagnetism and size-modulated electronic structures in two-dimensional cluster-based metal-organic frameworks

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Science China Chemistry 2024年第4期67卷 1334-1340页

作者： jing cheng Xingxing Li Jinlong Yang Key Laboratory of Precision and Intelligent Chemistry University of Science and Technology of ChinaHefei 230026China Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China

Cluster-assembled materials have attracted particular attention for their complex hierarchical structures and unique ***,the majority of cluster-based assemblies developed so far are either non-magnetic or only exhibit magnetic ordering with a relatively low Curie temperature,limiting their applications in ***,two-dimensional(2D)cluster-assembled materials with room-temperature magnetism remain highly *** this purpose,based on first principles calculations,we design a series of thermodynamically stable 2D cluster-based metal-organic frameworks(MOFs)Fe_(n)-(pyz)(n=1-6)by utilizing Fenmetal clusters as nodes and nitrogen-containing pyrazine ligands as organic *** 2D cluster-based MOFs exhibit robust ferrimagnetic ordering due to the strong d-p direct exchange interaction between d-electron spin of Fe_(n)(n=1-6)clusters and charge transfer-induced p-electron spin of pyrazine *** particular,the ferrimagnetic Curie temperatures are well above room temperature(up to 836 K).Additionally,altering the size of Fe_(n)clusters in Fe_(n)-(pyz)(n=1-6)MOFs results in diverse functional spintronic properties,including bipolar magnetic semiconductors,half semiconductors and Dirac half ***,these 2D assembled MOFs possess sizable magnetic anisotropy energies,up to 9.16 me V per formula.

关键词： metal-organic framework two-dimensional material half metal bipolar magnetic semiconductor magnet

Tin recovery from a low-grade tin middling with high Si content and low Fe content by reduction–sulfurization roasting with anthracite coal

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International Journal of Minerals,Metallurgy and Materials 2021年第2期28卷 210-220页

作者： jing-cheng Wang Lei Li Yong Yu State Key Laboratory of Complex Non-ferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China Engineering Research Center of Metallurgical Energy Conservation and Emission Reduction of Ministry of Education Kunming University of Science and TechnologyKunming 650093China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China

A new method for separating and recovering tin from a low-grade tin middling with high Si content and low Fe content by roasting with anthracite coal was researched by studying the reaction mechanism and performing an industrial test,in which the Sn was sulfurized into SnS(g)and then collected using a dust *** Fe–Sn alloy may be formed at roasting temperatures above 950°C,and like the roasting temperature increases,the Sn content and Sn activity in this Fe–Sn alloy ***,more FeS can be formed at higher temperatures and then the formation of FeO–FeS with a low melting point is promoted,which results in more serious sintering of this low-grade tin *** from the thermodynamics and kinetics points of view,the volatilization of the Sn decreases at extremely high roasting *** results of the industrial test carried out in a coal-fired rotary kiln show that the Sn volatilization rate reaches 89.7%and the Sn is concentrated in the collected dust at a high level,indicating that the Sn can be effectively extracted and recovered from the low-grade tin middling with a high Si content and low Fe content through a reduction–sulfurization roasting process.

关键词： low-grade tin middling tin recovery roasting process Fe-Sn alloy resource recycling

Analyzing the Urban Hierarchical Structure Based on Multiple Indicators of Economy and Industry: An Econometric Study in China

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Computer Modeling in Engineering & Sciences 2022年第6期131卷 1831-1855页

作者： jing cheng Yang Xie Jie Zhang School of Architecture Tsinghua UniversityBeijing100084China Beijing Tsinghua Tongheng Urban Planning&Design Institute Beijing100085China

For a city,analyzing its advantages,disadvantages and the level of economic development in a country is important,especially for the cities in China developing at flying *** corresponding literatures for the cities in China have not considered the indicators of economy and industry in *** this paper,based on multiple indicators of economy and industry,the urban hierarchical structure of 285 cities above the prefecture level in China is *** indicators from the economy,industry,infrastructure,medical care,population,education,culture,and employment levels are selected to establish a new indicator system for analyzing urban hierarchical *** factor analysis method is used to investigate the relationship between the variables of selected indicators and obtain the score of each common factor and comprehensive scores and rankings for 285 cities above the prefecture level in *** to the comprehensive scores,285 cities above the prefecture level are clustered into 15 levels by using K-means clustering ***,the hierarchical structure system of the cities above the prefecture level in China is obtained and corresponding policy implications are *** results and implications can not only be applied to the urban planning and development in China but also offer a reference on other developing *** methodologies used in this paper can also be applied to study the urban hierarchical structure in other countries.

关键词： Urban planning hierarchical structure prefecture-level city factor analysis method K-means clustering algorithm China

New Dopa-AIE Compound Used as Fluorescence Sensor Material： Specificity and Quantification for Cu（Ⅱ）

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Chinese Journal of Chemistry 2017年第3期35卷 335-340页

作者： Siwei Liu jing cheng Jiarui Xu PCFMLab and GDHPPC Lab School of Chemistry Sun Yat-sen University Guangzhou Guangdong 510275 China Department of Materials Soience and Engineering and Bioengineering Univer~s'ity of California Berkeley CA 94702 U. S. A.

As a paramagnetic metal ion, Cu(II) is challenging to be detected by conventional fluorescence sensor because of its unselective paramagnetic quenching effects on common fluorophores. By combining catechol with tetraphenylethene, a typical aggregation‐induced emission (AIE) moiety, we have successfully synthesized a new kind of catechol, the dopa‐AIE compound. Due to the properties of AIE core, the catechol has the “turn on” mechanism as a fluorescence chemosensor. Specifically, the new catechol has the unique detection selectivity on Cu(II) in solution. The fluorescence intensity has the maximum value when the molar ratio of the catechol to Cu(II) is 1∶1. Before and after this point, the fluorescence intensity shows a linear relationship with the copper ion concentration, increasing or decreasing. Thus, the quantitative calculation for Cu(II) or the dopa‐AIE compound could be done according to this response process.

关键词： dopamines biosensors copper fluorescence redox

Measuring spatio-temporal autocorrelation in time series data of collective human mobility

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Geo-Spatial Information Science 2019年第3期22卷 166-173页

作者： Yong Gao jing cheng Haohan Meng Yu Liu Institute of Remote Sensing and Geographic Information System School of Earth and Space SciencesPeking UniversityBeijingChina

Massive spatio-temporal big data about human mobility have become increasingly *** underlying dynamic patterns from these data is essential for understanding people’s behavior and urban ***-temporal autocorrelation analysis is an exploratory approach to recognizing data distribution in space and *** most widely used spatial autocorrelation measurements,such as Moran’s I and local indicators of spatial association(LISA),only apply to static data,so are powerless to spatio-temporal big data about human ***,we proposed a new method by extending Moran’s I to measure the spatial autocorrelation of time series *** the method was applied to taxi ride data in Beijing,China to reveal the spatial pattern of collective human *** result shows that there is strong positive spatio-temporal autocorrelation within the 5th Ring Road,weak negative spatio-temporal autocorrelation nearby the Sixth Ring Road,and almost no spatiotemporal autocorrelation between the *** spatial patterns of taxi travel were also *** method is useful for discovering underlying patterns from spatio-temporal big data to understand human mobility.

关键词： Taxi rides human mobility spatio-temporal autocorrelation Moran index