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Journal of Computer Science & Technology 2004年第2期19卷 158-168页

作者： Xian-SiTan Zong-Kaiyang LiangOu Jing-WenChen ya-Jiema DepartmentofElectronicsandInformation HuazhongUniversityofScienceandTechnologyWuhan430074P.R.China

An analytical framework for the performance of different protection switching restoration mechanisms with different protection policies in multi-Protocol Label Switching (mPLS) networks is developed, where the protection policy may be 1 + 1, 1:1, n:1 or n:m. As a general rule, it aims at the mPLS networks with the protection paths created in advance of fault occurrence without resources reserved, and it reroutes the protected traffic in the event of link or router failures while trying to maintain quality of service (QoS) requirements. Based on the proposed protocol for processing faults, an analytical model and an evaluating model are created, and the benefits and penalties of different mechanisms with different protection policies are evaluated. In particular, an improvement on the proposed protocol is presented to overcome the drawbacks of n:m protection policy in which m > 1 and n > 1.

关键词： mPLS fault restoration QoS analytical framework restoration policy

Effect of ultrasound on reverse leakage current of silicon Schottky barrier structure

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Journal of Semiconductors 2016年第12期37卷 5-11页

作者： O.ya Olikh K.V.Voitenko R.m.Burbelo Ja m.Olikh Faculty of Physics Taras Shevchenko National University of Kyiv V Lashkaryov Institute of Semiconductor Physics National Academy of Sciences of Ukraine

The influence of ultrasonic loading on reverse current-voltage characteristics of mo/n-n＋-Si structures has been investigated. The research of leakage current variation has been carried out for various ultrasonic wave frequencies （4.1 and 8.4 mHz）, intensities （up to 0.8 W/cm2） and loading temperatures （130-330 K）. The observed reversible acoustically induced increase in reverse currents was as large as 60%. It has been found that dominant charge transfer mechanisms are the thermionic emission （at high temperature） and the phonon-assisted tunneling （at low temperature）. The ultrasound loading affects both processes due to the decrease of Schottky barrier height and binding energy of the electron on the trap.

关键词： Schottky contact leakage current ultrasound influence

Diploid species phylogeny and evolutionary reticulation indicate early radiation of Ephedra in the Tethys coast

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Journal of Integrative Plant Biology 2023年第12期65卷 2619-2630页

作者： Qiong Yu Fu-Sheng yang ya-Xing Chen Hui Wu Stefanie m.Ickert-Bond Xiao-Quan Wang State Key Laboratory of Plant Diversity and Specialty Crops Institute of Botanythe Chinese Academy of SciencesBeijing100093 China China National Botanical Garden Beijing100093 China College of Life Sciences University of Chinese Academy of SciencesBeijing100049 China Department of Biology and Wildlife&UA museum of the North University of Alaska Fairbanks(UAF)FairbanksAK99775 USA

Reconstructing a robust species phylogeny and disentangling the evolutionary and biogeographic history of the gymnosperm genus Ephedra,which has a large genome and rich polyploids,remain a big *** we reconstructed a transcriptome-based phylogeny of 19 diploid Ephedra species,and explored evolutionary reticulations in this genus represented by 50 diploid and polyploid species,using four low-copy nuclear and nine plastid *** diploid species phylogeny indicates that the mediterranean species diverged first,and the remaining species split into three clades,including the american species(Clade A),***,and all other Asian species(Clade B).The single-gene trees placed *** sister to Clade A,Clade B,or Clades A+B in similar proportions,suggesting that radiation and gene flow likely occurred in the early evolution of *** addition,reticulate evolution occurred not only among the deep nodes,but also in the recently evolved South american species,which further caused difficulty in phylogenetic ***,we found that allopolyploid speciation was pervasive in *** study also suggests that Ephedra very likely originated in the Tethys coast during the late Cretaceous,and the South american Ephedra species have a single origin by dispersal from mexico or North america.

关键词： allopolyploidy biogeography Ephedra phylogenomics phylogeny reticulate evolution

Numerical and experimental study of continuous and discontinuous turbidity currents on a flat slope

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Journal of Hydrodynamics 2018年第6期30卷 1083-1092页

作者： Zhong-luan yan Rui-dong An Jia Li Yun Deng Yong Li ya-ya Xu State Key Laboratory of Hydraulics and mountain River Engineering Sichuan University Postdoctoral Research Station China Three Gorges Corporation Water Resource and Hydropower Investigation Design and Research Institute Co. Ltd. of Gansu

When the sediment and the dissolved matter laden in the river meet a clear water in reservoirs, the turbid water will plunge and spread into the clear water, forming the turbidity current and influencing the water quality and the life of the reservoir. Due to the unsteady nature of the flood, the turbidity current is unsteady. In the present study, we use the mIKE 3 computational fluid dynamics code to simulate continuous and discontinuous turbidity currents on a flat slope. With the model used by us, the turbulence is divided into two parts: the horizontal turbulence and the vertical turbulence, which are separately modeled by the Smagorinsky model and our model to capture the anisotropic turbulence. In this model, the sediment settling and deposition are considered. The simulation results concerning the flume water surface level, the front velocity and sediment concentration profiles are found consistent with the experimental data, particularly, for the sediment concentration profiles with an absolute mean error of 0.026 kg/m3and the root mean square error of 0.046 kg/m3. This finding suggests that this model can be used to well predict the turbidity current on the flat slope.

关键词： Turbidity current discontinuity numerical model turbulence Smagorinsky model

mobius Homogeneous Hypersurfaces with One Simple Principal Curvature in S^n+1

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Acta mathematica Sinica,English Series 2020年第9期36卷 1001-1013页

作者： ya Yun CHEN Xiu JI Tong Zhu LI Department of mathematics Beijing Institute of TechnologyBeijing 100081P.R.China

Let mob(S^n+1)denote the mobius transformation group of S^n+1.A hypersurface f:N^n→S^n+1 is called a mobius homogeneous hypersurface,if there exists a subgroup G■mob^(S^n+1)such that the orbit G(p)={Ф(p)Ф∈G}=f(m^n).In this paper,we classify the mobius homogeneous hypersurfaces in S^n+1 with at most one simple principal curvature up to a m?bius transformation.

关键词： mobius transformation group isometric transformation group mobius homogeneous hy-persurfaces homogeneous hypersurfaces

Commutation of Geometry-Grids and Fast Discrete PDE Eigen-Solver GPA

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Chinese Annals of mathematics,Series B 2023年第5期44卷 735-752页

作者： Jiachang SUN Jianwen CAO ya ZHANG Haitao ZHAO Laboratory of Parallel Software and Computational Science Institute of SoftwareChinese Academy ofSciencesBeijing 100190China

A geometric intrinsic pre-processing algorithm(GPA for short)for solving largescale discrete mathematical-physical PDE in 2-D and 3-D case has been presented by Sun(in 2022–2023).Different from traditional preconditioning,the authors apply the intrinsic geometric invariance,the Grid matrix G and the discrete PDE mass matrix B,stiff matrix A satisfies commutative operator BG=GB and AG=GA,where G satisfies G^(m)=I,mm(G).A large scale system solvers can be replaced to a more smaller block-solver as a pretreatment in real or complex *** this paper,the authors expand their research to 2-D and 3-D mathematical physical equations over more wide polyhedron grids such as triangle,square,tetrahedron,cube,and so *** give the general form of pre-processing matrix,theory and numerical test of *** conclusion that“the parallelism of geometric mesh pre-transformation is mainly proportional to the number of faces of polyhedron”is obtained through research,and it is further found that“commutative of grid mesh matrix and mass matrix is an important basis for the feasibility and reliability of GPA algorithm”.

关键词： mathematical-physical discrete eigenvalue problems Commutative operator Geometric pre-processing algorithm Eigen-polynomial factorization

Experimental study of evaporation of sessile water droplet on PDmS surfaces

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Acta mechanica Sinica 2013年第6期29卷 799-805页

作者： Ying-Song Yu Zi-Qian Wang ya-Pu Zhao Department of Engineering mechanics School of Civil Engineering & ArchitectureHubei University of Technology State Key Laboratory of Nonlinear mechanics Institute of MechanicsChinese Academy of Sciences

Evaporation of sessile water droplet on polydimethylsiloxane （PDmS） surfaces with three different curing ratios （5：1, 10：1, and 20：1） was experimentally investigated in this paper. We show that the constant contact radius （CCR） evaporation on surface with high curing ratio lasts longer than that with low curing ratio. We also measured Young＇s moduli of PDmS films by using atomic force microscopy （AFm） and simulated surface deformation of PDmS films induced by sessile water droplet. With increasing curing ratio of PDmS film, Young＇s modulus of PDmS film is getting lower, and then there will be larger surface deformation and more elastic stored energy. Since such energy acts as a barrier to keep the three-phase contact line pinned, thus it will result in longer CCR evaporation on PDmS surface with higher curing ratio.

关键词： Droplet evaporation PDmS Constant contact radius mode Constant contact angle mode Force- displacement curve Surface deformation Liquid-vapor interfacial tension

Kiwifruit(Actinidia chinensis)R1R2R3-mYB transcription factor AcmYB3R enhances drought and salinity tolerance in Arabidopsis thaliana

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Journal of Integrative Agriculture 2019年第2期18卷 417-427页

作者： ZHANG ya-bin TANG Wei WANG Li-huan HU ya-wen LIU Xian-wen LIU Yong-sheng Key Laboratory of Bio-Resource and Eco-Environment of ministry of Education College of Life SciencesSichuan UniversityChengdu 610065P.R.China School of Food Science and Engineering Hefei University of TechnologyHefei 230009P.R.China

Kiwifruit is an important fruit crop that is highly sensitive to environmental stresses,such as drought,heat,cold,water logging and *** it is indispensable to identify stress-responsive candidate genes in kiwifruit cultivars for the stress resistance *** we report the isolation and characterization of a novel kiwifruit R1R2R3-mYB homolog(AcmYB3R)whose expression was induced by drought,salinity and cold *** vitro assays showed that AcmYB3R is a nuclear protein with transcriptional activation activity by binding to the cis-element of the kiwifruit orthologue of G2/m phase-specific gene *** Arabidopsis transgenic plants overexpressing AcmYB3R showed drastically enhanced tolerance to drought and salt *** expressions of stress-responsive genes such as RD29A,RD29B,COR15A and RD22 were prominently up-regulated by ectopic expression of Ac *** study provides a valuable piece of information for functional genomics studies of kiwifruit and molecular breeding in improving stress tolerance for crop production.

关键词： kiwifruit R1R2R3-mYB drought abiotic stress

Game theory based finite-time formation control using artificial potentials for tethered space net robot

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Chinese Journal of Aeronautics 2024年第8期37卷 358-372页

作者： Yifeng mA Yizhai ZHANG Panfeng HUANG ya LIU Fan ZHANG The Research Center for Intelligent Robotics School of AstronauticsNorthwestern Polytechnical UniversityXi’an 710072China School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

The Tethered Space Net Robot(TSNR)is an innovative solution for active space debris capture and *** large envelope and simple capture method make it an attractive option for this ***,capturing maneuverable debris with the flexible and elastic underactuated net poses significant *** address this,a novel formation control method for the TSNR is proposed through the integration of differential game theory and robust adaptive control in this ***,the trajectory of the TSNR is obtained through the solution of a real-time feedback pursuit-evasion game with a dynamic target,where the primary condition is to ensure the stability of the ***,to minimize tracking errors and maintain a specific configuration,a robust adaptive formation control scheme with Artificial Potential Field(APF)based on a Finite-Time Convergent Extended State Observer(FTCESO)is *** proposed control method has a key advantage in suppressing complex oscillations by a new adaptive law,thus precisely maintaining the ***,numerical simulations are performed to demonstrate the effectiveness of the proposed scheme.

关键词： Game theory Formation control Artificial potential field Relative distance constraint Tethered space net robot(TSNR)

Effect of nozzle type on fluid flow, solidification, and solute transport in mold with mold electromagnetic stirring

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Journal of Iron and Steel Research International 2022年第2期29卷 237-246页

作者： ya-dong Wang Li-feng Zhang Wen yang Ying Ren School of metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China State Key Lab of metastable materials Science and Technology School of Mechanical EngineeringYanshan UniversityQinhuangdao066004HebeiChina

The mathematical model of coupling fluid flow,heat transfer,solidification,solute transport,and the electromagnetic field of the bloom in the upper part of the strand was established with three nozzle ***,the flow field,distribution of the temperature,solidification,and macrosegregation of carbon were investigated and compared by numerical *** the case of the straight submerged entry nozzle(SEN),the molten steel flows down deep into the liquid pool,and the depth of the jet flow reaches about 1.0 m beneath the *** jetting zone is the high-temperature *** the case of two-port SEN and four-port SEN,the flow patterns and distribution of temperature in the central longitudinal section are *** jet flow impinges directly on the initially solidified shell and then it is divided into two longitudinal *** heat of molten steel is dissipated along with the longitudinal *** negative segregation band was generated near the bloom surface due to the washing effect by the rotating flow at the solidification front with three nozzle *** negative segregation deteriorates gradually with the number of ports decreasing.

关键词： Submerged entry nozzle Fluid flow Solidification Solute transport mold electromagnetic stirring