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Flex Ethernet Technology and Application in 5G Mobile Transport Network

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China Communications 2021年第2期18卷 250-258页

作者： meng zhang Research Institute of Telecommunications Transmission(RITT) China Academy of Information Communications Technology(CAICT)MIITBeijing 100191China

With the advent of 5G era,the rise of cloud services,virtual reality/virtual reality(AR/VR),vehicle networking and other technologies has put forward new requirements for the bandwidth and delay of the bearer *** Ethernet technology cannot meet the new requirements very *** Ethernet(FlexE)technology has emerged as the times *** paper introduces the background,standardization process,functional principle,application mode and technical advantages of FlexE technology,and finally analyses its application prospects and shortcomings in 5G mobile transport network.

关键词： Flex Ethernet(FlexE) 5G mobile transport network network slicing

Biomechanical Effects of Tibial Stems with Different Structures on Human Knee Joint after Total Knee Arthroplasty: A Finite Element Analysis

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Journal of Bionic Engineering 2022年第1期19卷 197-208页

作者： meng zhang Kaiwen zhang He Gong Department of Engineering Mechanics Nanling CampusJilin UniversityChangchun130025China

Porous structure in orthopedic prosthesis may reduce micromotion and increase the service life of *** purposes of this study were to compare the influence of the tibial stems with solid and porous structures in Total Knee Arthroplasty(TKA)on knee joint and prostheses,and to improve the mechanical stability of the host bone by seeking favorable structure for the tibial *** Finite Element(FE)models of TKA knee with four different structures in the middle segment of the tibial stem(i.e.,solid,cubic,truncated cubic,and octahedral structures)were *** distributions of von Mises stress in the knee joint,tibial prosthesis and proximal tibia,and the compressive stresses of the tibial prosthesis and ultra-high-molecular-weight polyethylene for the four FE models were *** results showed that the tibial stem filled with the octahedral structure has the best mechanical performance among the above four types of tibial *** could effectively reduce the stress concentration and stress shielding effects,and provide an improved mechanical environment for knee joint after *** study would shed some lights on the design and fabrication of porous implants targeted to biomedical applications.

关键词： Total knee arthroplasty Tibial stem Porous structure Finite element analysis Mechanical performance

A Quantitative Description of Complex Adaptive System:The Self-Adaptive Mechanism of the Material Purchasing Management System Towards the Changing Environment

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Journal of Systems Science & Complexity 2016年第1期29卷 151-170页

作者： zhang meng CUI Jinchuan Academy of Mathematics and Systems Science Chinese Academy of Sciences

This paper demonstrates a new interpretation of the material purchasing management system(MPMS) from the perspective of complex adaptive systems(CAS).Within the framework of CAS,the authors design the self-adaptive mechanism of the MPMS responding to the changing environment,such as the change of the price,by using risk measurement theory,modern portfolio theory(MPT) and the information of the material's modifying *** a bottom-up systems view,CAS focuses on the individual level and studies system's overall complexity by analyzing the mutual competition and adaptation among the *** paper demonstrates a quantitative description of CAS by discussing the MPMS which can be viewed as a kind of CAS,and makes numerical simulations of Daqing oilfield *** to the benchmarks,the authors set the simulations show that the self-adaptive mechanism adapts well to the change of the material's market ***,this paper accomplishes a numerical simulation of CAS's quantitative self-adaptive mechanism responding to the environment's change.

关键词： Complex adaptive system(CAS) CVaR material purchasing management system(MPMS) modern portfolio theory(MPT) self-adaptive mechanism

Enrichment of topographic road database for the purpose of routing and navigation

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International Journal of Digital Earth 2014年第5期7卷 411-431页

作者： meng zhang Wei Yao Liqiu meng Department of Earth and Environmental Sciences Xi’an Jiaotong UniversityXi’anChina Department of Photogrammetry and Remote Sensing Technische Universitaet MuenchenMunichGermany Department of Cartography Technische Universitaet MuenchenMunichGermany

With growing demand on multi-purpose or multi-modal navigation,the route calculation needs to traverse semantically enriched road networks for different transportation ***,operational route planning algorithms reveal rather limited performances or their potential for comprehensive applications are constrained by the unavailable or insufficient interoperation among the under-lying geo-data that are separately maintained in different spatial *** overcome this limitation,a novel approach has been proposed to integrate the routing-relevant information from different data sources,which involves three processes:(1)automatic matching to identify the corresponding road objects between different datasets;(2)interaction to refine the automatic matching result;and(3)transferring the routing-relevant information from one data-set to *** process(1),the Delimited Stroke Oriented algorithm is employed to achieve the automatic data matching between different datasets,which has revealed a high matching rate and *** uncertain matching problems occur in areas where topological conditions are too complicated or *** remaining unmatched or wrongly matched objects are treated in process(2),with the help of a series of interaction *** the basis of refined matching results after the interaction,process(3)is dedicated to automatic integration of the routing-relevant information from different data sources.

关键词： data matching data integration routing-relevant geospatial data-set road network

Effect of Inlet and Outlet Manifolds on Regenerative Cooling in LOX/Methane Thrust Chambers

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Journal of Thermal Science 2021年第2期30卷 517-529页

作者： zhang meng SUN Bing SONG Jiawen School of Astronautics Beihang UniversityBeijing 100191China

Regenerative cooling is considered one of the most effective cooling methods used in liquid rocket engines and has been widely studied in recent *** the effect of the non-uniform flow in cooling channels caused by inlet and outlet manifolds did not attract much *** this paper,we carried out the coupled flow and heat transfer of combustion and regenerative cooling in a LOX/Methane (LOX means liquid oxygen) engine and compared the results with and without ***,three different configurations of the inlet and outlet manifolds were also *** results show that the parameters averaged in the circumferential direction are less affected by the ***,the existence of the manifolds will make the distribution of mass flow rate as well as wall temperature non-uniform along the circumferential *** addition,when the angles between inlet and outlet are 0°,90° and 180°,the maximum temperature difference along the circumference of throat increases by 90.1%,151.2% and 229.5%,respectively,compared with that without *** indicates that the larger the angle between inlet and outlet,the greater the non-uniformity of mass flow rate and wall temperature along the circumferential *** a result,extra thermal stress will be generated which could cause some negative effects on the rocket engines.

关键词： regenerative cooling conjugate heat transfer inlet and outlet manifolds non-uniform flow

Characterization methods of organic electrode materials

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Journal of Energy Chemistry 2021年第6期30卷 291-303,I0008页

作者： meng zhang Wenjun Zhou Weiwei Huang School of Environmental and Chemical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin 300071China

The development of novel organic electrode materials is of great significance for improving the reversible capacity and cycle stability of rechargeable *** practical application,it is essential to characterize the electrode materials to study their structures,redox mechanisms and electrochemical *** this review,the common characterization methods that have been adopted so far are summarized from two aspects:experimental characterization and theoretical *** experimental characterization is introduced in detail from structural characterization,electrochemical characterization and electrode reaction chara *** experimental purposes and working principles of various experimental characterization methods are briefly *** the auxilia ry means,theoretical calculation provides the theoretical basis for characterizing the electrochemical reaction mechanism of organic electrode *** these characterizations,we will have a deep understanding about the material structures,electrochemical redox mechanisms,electrochemical properties and the relationships of *** is hoped that this review would help researchers to select the suitable characterization methods to analyze the structures and performances of organic electrode materials quickly and effectively.

关键词： Organic electrode materials Structural characterization Electrochemical characterization Electrode reaction characterization Theoretical calculation

Sedimentation process of saturated sand under impact loading

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Science China(Technological Sciences) 2005年第z1期48卷 81-94页

作者： zhang Junfeng meng Xiangyue Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

The initial small inhomogeneity of saturated sand could be amplified during the sedimentation process after liquefaction, and cracks could be observed in the sand column. Layers of fine sand could also be found at the exact place where cracks developed and disappeared. The phenomena and the whole process were experimentally shown by X-rays images. To account for the phenomena, a linearized stability analysis of the sedimentation of saturated sand was conducted; however, it did not produce a satisfactory result. A three-phase flow model describing the transportation of fine sand is presented in this paper. It is shown that such a kind of erosion/deposition model was qualitatively in good agreement with the experimental observation.

关键词： sedimentation process, liquefaction, stability analysis, three-phase flow model.

The Twisted Homology of Simplicial Set

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Acta Mathematica Sinica,English Series 2022年第10期38卷 1781-1802页

作者： meng meng zhang Jing Yan LI Jie WU School of Mathematical Sciences Hebei Normal UniversityShijiazhuang 050024P.R.China Yanqi Lake Beijing Institute of Mathematical Sciences and Applications Beijing 101408P.R.China

In this article,we give a generalization of δ-twisted homology introduced by Jingyan Li,Vladimir Vershinin and Jie Wu,called Δ-twisted homology,which enriches the theory of δ-(co)homology introduced by Alexander Grigor’yan,Yuri Muranov and Shing-Tung *** show that the Mayer-Vietoris sequence theorem holds for Δ-twisted *** the Δ-twisted ideas to Cartesian products,we introduce the notion of Δ-twisted Cartesian product on simplicial sets,which generalizes the classical work of Barratt,Gugenheim and Moore on twisted Cartesian products of simplicial *** certain hypothesis,we show that the coordinate projection of Δ-twisted Cartesian product admits a fibre bundle structure.

关键词： Simplicial set Δ-Twisted homology Homotopy type Fibre bundle

Highly Sensitive Ethanol Gas Sensor Based on Ag Nanoparticles Decorated In_(2)O_(3)

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Chemical Research in Chinese Universities 2024年第6期40卷 1033-1040页

作者： zhang Susu zhang meng GUO Ying State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029P.R.China

Ag nanoparticle decorated In_(2)O_(3) composites for high sensitivity and high selectivity detection of ethanol were prepared by hydrothermal and annealing *** effects of Ag content on the sensing properties of Ag decorated In_(2)O_(3) sensors were also *** was found that all Ag decorated In_(2)O_(3) sensors exhibited better sensing performance in terms of sensitivity and selectivity compared to pure In_(2)O_(3) *** optimizing the addition amount of Ag,the 7%-Ag/In_(2)O_(3) sensor showed the highest response to ethanol (35.6 vs.100 ppm,ppm=parts per million);which was about seven times higher than that of the pure In_(2)O_(3) sensor at 270 ℃.The improved performance of the Ag-In_(2)O_(3) composite sensor can be attributed to the catalytic effect of silver and the Schottky barrier formed at the Ag-In_(2)O_(3) interface.

关键词： Ag In_(2)O_(3) Schottky barrier Ethanol Sensor