期刊文献+
共找到16篇文章
< 1 >
每页显示 20 50 100
An extended improved global structure model for influential node identification in complex networks 被引量:1
1
作者 Jing-Cheng Zhu Lun-Wen Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第6期772-781,共10页
Accurate identification of influential nodes facilitates the control of rumor propagation and interrupts the spread of computer viruses.Many classical approaches have been proposed by researchers regarding different a... Accurate identification of influential nodes facilitates the control of rumor propagation and interrupts the spread of computer viruses.Many classical approaches have been proposed by researchers regarding different aspects.To explore the impact of location information in depth,this paper proposes an improved global structure model to characterize the influence of nodes.The method considers both the node’s self-information and the role of the location information of neighboring nodes.First,degree centrality of each node is calculated,and then degree value of each node is used to represent self-influence,and degree values of the neighbor layer nodes are divided by the power of the path length,which is path attenuation used to represent global influence.Finally,an extended improved global structure model that considers the nearest neighbor information after combining self-influence and global influence is proposed to identify influential nodes.In this paper,the propagation process of a real network is obtained by simulation with the SIR model,and the effectiveness of the proposed method is verified from two aspects of discrimination and accuracy.The experimental results show that the proposed method is more accurate in identifying influential nodes than other comparative methods with multiple networks. 展开更多
关键词 complex network influential nodes extended improved global structure model SIR model
下载PDF
Global Structure Stability of Riemann Solution of Quasilinear Hyperbolic System of Conservation Law in Presence of Boundary:Shocks and Contact Discontinuities
2
作者 JIN Cui-Lian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第11期1027-1032,共6页
In this paper, we investigate a class of mixed initial-boundary value problems for a kind of n × n quasilinear hyperbolic systems of conservation laws on the quarter plan. We show that the structure of the pieeew... In this paper, we investigate a class of mixed initial-boundary value problems for a kind of n × n quasilinear hyperbolic systems of conservation laws on the quarter plan. We show that the structure of the pieeewise C^1 solution u = u(t, x) of the problem, which can be regarded as a perturbation of the corresponding Riemann problem, is globally similar to that of the solution u = U(x/t) of the corresponding Riemann problem. The piecewise C^1 solution u = u(t, x) to this kind of problems is globally structure-stable if and only if it contains only non-degenerate shocks and contact discontinuities, but no rarefaction waves and other weak discontinuities. 展开更多
关键词 Riemann problem hyperbolic system conservation laws global structure stability
下载PDF
Global structure stability of impact-induced tensile waves in phase-transforming materials
3
作者 黄守军 王静静 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第9期1155-1166,共12页
The global structure stability of the impact-induced tensile waves mentioned by Huang (Huang, S. J. Impact-induced tensile waves in a kind of phase-transforming materials. IMA Journal of Applied Mathematics, 76, 847-... The global structure stability of the impact-induced tensile waves mentioned by Huang (Huang, S. J. Impact-induced tensile waves in a kind of phase-transforming materials. IMA Journal of Applied Mathematics, 76, 847-858 (2011)) is considered. By introducing Riemann invariants, the governing equations of motion are reduced into a 2 ~ 2 diagonally strictly hyperbolic system. Then, with the aid of the theory on the typical free boundary problem and maximally dissipative kinetics, the global structure stability of the impact-induced tensile waves propagating in a phase-transforming material is proved. 展开更多
关键词 global structure stability impact-induced tensile wave phase boundary shock wave rarefaction wave
下载PDF
Global structure of spectra of periodic non-Hermitian Jacobi operators
4
作者 Hui Lu Jiangong You 《Science China Mathematics》 SCIE CSCD 2024年第12期2753-2770,共18页
We give global structure of spectra of periodic non-Hermitian Jacobi operators by the discriminant and its stationary points. We also give necessary and sufficient conditions for real spectra and single interval spectra.
关键词 periodic Jacobi operator non-Hermitian operator global structure real spectra
原文传递
GLOBAL STRUCTURES OF THE PLANE CUBIC SYSTEM WITH THE STELLAR NODE 被引量:1
5
作者 杨殿武 姚蔚红 李学敏 《Annals of Differential Equations》 1996年第4期489-501,共13页
In this paper, we initiate the introduction of concepts of region of type Ⅰ-Ⅳ in thephase plane, discuss topological classifications of global structure of the plane cubic system with the stellar node, and give the ... In this paper, we initiate the introduction of concepts of region of type Ⅰ-Ⅳ in thephase plane, discuss topological classifications of global structure of the plane cubic system with the stellar node, and give the twenty-six global structures and criteria by theright-hand palynominal coefficients of system. 展开更多
关键词 Stellar node global structure
原文传递
Global structure and seasonal variations of the migrating 6-h tide observed by SABER/TIMED 被引量:2
6
作者 LIU MoHan XU JiYao +1 位作者 YUE Jia JIANG GuoYing 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第7期1216-1227,共12页
Ten years of SABER/TIMED temperature data are used to analyze the global structure and seasonal variations of the migrating 6-h tide from the stratosphere to the lower thermosphere. The amplitudes of the migrating 6-h... Ten years of SABER/TIMED temperature data are used to analyze the global structure and seasonal variations of the migrating 6-h tide from the stratosphere to the lower thermosphere. The amplitudes of the migrating 6-h tide increase with altitudes. In the stratosphere, the migrating 6-h tide peaks around 35°N/S. The climatologically annual mean of the migrating 6-h tide clearly shows the manifestation of the(4, 6) Hough mode between 70 and 90 km that peaks at the equator and near 35°N/S. Above 90 km, the 6-h tide shows more than one Hough mode with the(4, 6) mode being the dominant one. The migrating 6-h tide is stronger in the southern hemisphere. Annual, semiannual, 4-, and 3-month oscillations are the four dominant seasonal variations of the tidal amplitude. In the stratosphere and stratopause, the spring enhancement of the 6-h tide at middle latitudes is the most conspicuous feature. From the mesosphere to the lower thermosphere, the tidal amplitude at low latitudes is gradually in the scale of that at middle latitudes and exhibits different temporal variations at different altitudes and latitudes. Both ozone heating in the stratosphere and the background atmosphere probably affect the generation and the seasonal variations of the migrating 6-h tide. In addition, the non-linear interaction between different tidal harmonics is another possible mechanism. 展开更多
关键词 migrating tide global structure seasonal variations non-linear interaction bispectral analysis
原文传递
Global Topological Structure of a Class of Plane Homogeneous Fifth System with Six Special Direction
7
作者 GAO Jie JI Fa-jun 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期540-547,共8页
In this paper, a class of plane homogeneous fifth system with six special direction is studied, and the global topological classification and coefficient conditions is discussed.
关键词 homogeneous fifth system special direction global structure
下载PDF
Global Power Structure Shifted and Transitional Multi-polarity Emerged
8
作者 Prof.YU Zhengliang is senior research fellow of Shanghai Institutes for International Studies. 《国际展望》 2010年第4期1-13,共13页
The world is facing the third important global power shift.The United States,EU, Japan,Russia,China,and the newly emerging power group are becoming the six big forces in the international center stage,while the former... The world is facing the third important global power shift.The United States,EU, Japan,Russia,China,and the newly emerging power group are becoming the six big forces in the international center stage,while the former three forces and the latter three belong to two groups,waning and waxing respectively.The major shift in the global balance of power is bound to give rise to the transitional multi-polar configuration,which implies a shifting of leadership over the configuration,China and U.S.outweighing other forces,global issues looming large,homogeneity blending with heterogeneity,and a shifting center of world powers.The transitional multi-polar configuration is all about change,upon which China is one of the decisive forces. 展开更多
关键词 global Power structure Shifted and Transitional Multi-polarity Emerged
下载PDF
Unprecedented Global Transition
9
作者 wang honggang fu yu +6 位作者 chen xiangyang yao kun han liqun han yiyuan wang lei su jingxiang ren weidong 《Contemporary International Relations》 2018年第3期1-12,共12页
In 2017, the 10th anniversary of the subprime mortgage crisis and 100th anniversary of the Russian October Revolution, the Communist Party of China held its 19th National Congress to meet the challenges that China and... In 2017, the 10th anniversary of the subprime mortgage crisis and 100th anniversary of the Russian October Revolution, the Communist Party of China held its 19th National Congress to meet the challenges that China and the world are undergoing in development, reform, and transition.The global economy is recovering but structural issues are unresolved.Against the backdrop of progressive multilateralism, international security risks have increased because of social disarray and transition risks. The global governance agenda is driven forward only with difficulty, and a multilateral governance system is urgently needed. 展开更多
关键词 World politics adjustment global structure global governance
下载PDF
Flora, life form characteristics, and plan for the promotion of biodiversity in South Korea's Globally Important Agricultural Heritage System, the traditional Gudeuljang irrigated rice terraces in Cheongsando 被引量:9
10
作者 Hong Chul PARK Chaang Hveon OH 《Journal of Mountain Science》 SCIE CSCD 2017年第6期1212-1228,共17页
The objectives of this study were to analyze the biodiversity of the Traditional Gudeuljang Irrigated Rice Terraces in Cheongsando, South Korea's representative GIAHS(Globally Important Agricultural Heritage Syste... The objectives of this study were to analyze the biodiversity of the Traditional Gudeuljang Irrigated Rice Terraces in Cheongsando, South Korea's representative GIAHS(Globally Important Agricultural Heritage System) site, with reference to position and land-use features, and to develop a plan to promote agricultural biodiversity in the region. We confirmed approximately 54,000 m2 of Gudeuljang paddy fields by an on-site survey. Of the Traditional Gudeuljang Irrigated Rice Terraces confirmed by onsite inspection, our survey showed that approximately 24,000 m2 are currently being used as paddy fields, approximately 15,000 m2 are being used as dry fields, and approximately 14,000 m2 are fallow. In terms of other non-agricultural land use, there was grassland, including graveyards; artificial arboreal land, such as orchards, rivers and wetlands, and man-made facilities, such as roads and residences. We also confirmed that the Traditional Gudeuljang Irrigated Rice Terraces had higher plant species diversity than conventional terraced rice paddies, and there was a difference in life form characteristics between the two types. Although the superficial topsoil structure is thesame for the Traditional Gudeuljang Irrigated Rice Terraces(TGIRTs) and conventional terraced rice paddies, it is thought that the differences in the subsurface structure of the TGIRTs contribute greatly to species and habitat diversity. However, the TGIRTs in Cheongsando are facing degeneration, due to damage and reduction in agricultural activity. The main cause is the reduction in the number of farming households due to an aging population in Cheongsando. In order to address this problem, we proposed a management plan, related to fallow paddy fields in South Korea, to initiate voluntary activities in the TGIRTs. 展开更多
关键词 globally Important Agricultural Heritage System Rice terrace Agricultural biodiversity Topsoil structure Gudeuljang
下载PDF
Outliers rejection in similar image matching
11
作者 Qingqing CHEN Junfeng YAO 《Virtual Reality & Intelligent Hardware》 2023年第2期171-187,共17页
Background Image matching is crucial in numerous computer vision tasks such as 3D reconstruction and simultaneous visual localization and mapping.The accuracy of the matching significantly impacted subsequent studies.... Background Image matching is crucial in numerous computer vision tasks such as 3D reconstruction and simultaneous visual localization and mapping.The accuracy of the matching significantly impacted subsequent studies.Because of their local similarity,when image pairs contain comparable patterns but feature pairs are positioned differently,incorrect recognition can occur as global motion consistency is disregarded.Methods This study proposes an image-matching filtering algorithm based on global motion consistency.It can be used as a subsequent matching filter for the initial matching results generated by other matching algorithms based on the principle of motion smoothness.A particular matching algorithm can first be used to perform the initial matching;then,the rotation and movement information of the global feature vectors are combined to effectively identify outlier matches.The principle is that if the matching result is accurate,the feature vectors formed by any matched point should have similar rotation angles and moving distances.Thus,global motion direction and global motion distance consistencies were used to reject outliers caused by similar patterns in different locations.Results Four datasets were used to test the effectiveness of the proposed method.Three datasets with similar patterns in different locations were used to test the results for similar images that could easily be incorrectly matched by other algorithms,and one commonly used dataset was used to test the results for the general image-matching problem.The experimental results suggest that the proposed method is more accurate than other state-of-the-art algorithms in identifying mismatches in the initial matching set.Conclusions The proposed outlier rejection matching method can significantly improve the matching accuracy for similar images with locally similar feature pairs in different locations and can provide more accurate matching results for subsequent computer vision tasks. 展开更多
关键词 Feature matching Outlier removal Motion consistency Similar image matching global structures
下载PDF
Two dimensional GeO_(2)/MoSi_(2)N_(4)van der Waals heterostructures with robust type-Ⅱ band alignment 被引量:1
12
作者 Xueping Li Peize Yuan +5 位作者 Lin Li Ting Liu Chenhai Shen Yurong Jiang Xiaohui Song Congxin Xia 《Frontiers of physics》 SCIE CSCD 2023年第1期115-122,共8页
Constructing two-dimensional(2D)van der Waals heterostructures(vdWHs)can expand the electronic and optoelectronic applications of 2D semiconductors.However,the work on the 2D vdWHs with robust band alignment is still ... Constructing two-dimensional(2D)van der Waals heterostructures(vdWHs)can expand the electronic and optoelectronic applications of 2D semiconductors.However,the work on the 2D vdWHs with robust band alignment is still scarce.Here,we employ a global structure search approach to construct the vdWHs with monolayer MoSi_(2)N_(4)and widebandgap GeO_(2).The studies show that the GeO_(2)/MoSi_(2)N_(4)vdWHs have the characteristics of direct structures with the band gap of 0.946 eV and typeII band alignment with GeO_(2)and MoSi_(2)N_(4)layers as the conduction band minimum(CBM)and valence band maximum(VBM),respectively.Also,the direct-to-indirect band gap transition can be achieved by applying biaxial strain.In particular,the 2D GeO_(2)/MoSi_(2)N_(4)vdWHs show a robust type-II band alignment under the effects of biaxial strain,interlayer distance and external electric field.The results provide a route to realize the robust type-II band alignment vdWHs,which is helpful for the implementation of optoelectronic nanodevices with stable characteristics. 展开更多
关键词 van der Waals heterostructures wide gap material global structure search robust type-II band alignment
原文传递
Global Solutions and Interactions of Non-selfsimilar Elementary Waves for n-D Non-homogeneous Burgers Equation
13
作者 Yuan-an ZHAO Gao-wei CAO Xiao-zhou YANG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2023年第4期830-853,共24页
We investigate the global structures of the non-selfsimilar solutions for n-dimensional(n-D) nonhomogeneous Burgers equation, in which the initial data has two different constant states, which are separated by a(n-1)-... We investigate the global structures of the non-selfsimilar solutions for n-dimensional(n-D) nonhomogeneous Burgers equation, in which the initial data has two different constant states, which are separated by a(n-1)-dimensional sphere. We first obtain the expressions of n-D shock waves and rarefaction waves emitting from the initial discontinuity. Then, by estimating the new kind of interactions of the related elementary waves,we obtain the global structures of the non-selfsimilar solutions, in which ingenious techniques are proposed to construct the n-D shock waves. The asymptotic behaviors with geometric structures are also proved. 展开更多
关键词 non-homogeneous burgers equation n-dimensional Riemann problem global singular structure non-selfsimilar solution interactions of elementary waves
原文传递
Co-developing an international TLS network for the 3D ecological understanding of global trees:System architecture,remote sensing models,and functional prospects
14
作者 Yi Lin Sagi Filin +1 位作者 Roland Billen Nobuya Mizoue 《Environmental Science and Ecotechnology》 SCIE 2023年第4期38-51,共14页
Trees are spread worldwide,as the watchmen that experience the intricate ecological effects caused by various environmental factors.In order to better understand such effects,it is preferential to achieve finely and f... Trees are spread worldwide,as the watchmen that experience the intricate ecological effects caused by various environmental factors.In order to better understand such effects,it is preferential to achieve finely and fully mapped global trees and their environments.For this task,aerial and satellite-based remote sensing(RS)methods have been developed.However,a critical branch regarding the apparent forms of trees has significantly fallen behind due to the technical deficiency found within their globalscale surveying methods.Now,terrestrial laser scanning(TLS),a state-of-the-art RS technology,is useful for the in situ three-dimensional(3D)mapping of trees and their environments.Thus,we proposed co-developing an international TLS network as a macroscale ecotechnology to increase the 3D ecological understanding of global trees.First,we generated the system architecture and tested the available RS models to deepen its ground stakes.Then,we verified the ecotechnology regarding the identification of its theoretical feasibility,a review of its technical preparations,and a case testification based on a prototype we designed.Next,we conducted its functional prospects by previewing its scientific and technical potentials and its functional extensibility.Finally,we summarized its technical and scientific challenges,which can be used as the cutting points to promote the improvement of this technology in future studies.Overall,with the implication of establishing a novel cornerstone-sense ecotechnology,the co-development of an international TLS network can revolutionize the 3D ecological understanding of global trees and create new fields of research from 3D global tree structural ecology to 3D macroecology. 展开更多
关键词 global trees Terrestrial laser scanning(TLS) International TLS network Three-dimensional(3D)ecotechnology 3D global tree structural ecology 3D macroecology
原文传递
Global Spiral Patterns in Galaxies : A Review of the Density Wave Theory from the Theoretical Perspective 被引量:1
15
作者 Chia Chiao Lin Department of Mathematics, Massachusetts Institute of Technology 77 Massachusetts Avenue Cambridge, MA 02139, USA 《Tsinghua Science and Technology》 SCIE EI CAS 1998年第1期27-42,共16页
The density wave theory of galactic spirals is a semi empirical theory consisting of the analysis of physically plausible mathematical models, the synthesis of extensive observational data, and an examination of the ... The density wave theory of galactic spirals is a semi empirical theory consisting of the analysis of physically plausible mathematical models, the synthesis of extensive observational data, and an examination of the applicability of the theoretical predictions of particular models for the interpretation of observational data. In this paper, the theory is reviewed from the general perception of order and chaos in dynamical systems. Prominent among the observational data is the well established morphological classification of galaxies according to Edwin Hubble, the luminosity class of Sidney van den Bergh, and the coexistence of regular and irregular global structures in many galaxies, as was first discovered in the whirlpool galaxy M51 by Fritz Zwicky. The regular structure is prominently observed in red and in infrared, and the irregular in blue and at 21 cm radio frequency. These and other data led to the concept of the existence of an essentially standing wave pattern in the older evolved stars, which in turn acts as a backbone for the global structure of the galaxy as a whole. Dynamically, the existence of irregular structures in the interstellar medium reflects the natural state of turbulent motion in gaseous motion at high speeds. In contrast, the essentially collisionless stellar system has a substantial 'microscale' of epicyclic motion that prevents, or smoothes out, irregularities on scales. It is pointed out that the spiral structure in galaxies is but one class of interesting phenomena that crucially relates to universal gravitation. Astronomical phenomena on all scales, from planets and satellites to protostars, stars and galaxies and the whole universe present other challenges to both theorists and observers, representing a wide field of opportunities for fruitful research. At the present time, they are being successfully met in individual cases through the development of new observational techniques to cover all frequencies of electromagnetic radiation and through the development of new analytical and computational methods. 展开更多
关键词 density wave theory galactic spirals galaxy regular and irregular global structures
原文传递
Characteristic analysis of hydraulic hybrid vehicle based on limit cycle
16
作者 CHEN YanLi LIU ShunAn +1 位作者 SHANG Tao ZHANG YuanKun 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第4期1031-1036,共6页
The theory of limit cycles was applied to hydraulic hybrid vehicle (HHV) to analyze the dynamic characteristics of the system. The exact mathematical models based on configuration diagram of HHV were built to study on... The theory of limit cycles was applied to hydraulic hybrid vehicle (HHV) to analyze the dynamic characteristics of the system. The exact mathematical models based on configuration diagram of HHV were built to study on equilibrium points, nonexistence of limit cycle and stability of equilibrium points. The analysis showed that if the Young's modulus of fluid is neglected, the equilibrium points of the system will be distributed on both sides of the initial function. In addition, there is a unique equilibrium point according to the practical signification of the system parameters. The nonexistence analysis showed that there is no limit cycle for the system, no matter how the viscosity coefficient B changes. The stability analysis of equilibrium points showed that the system is asymptotically stable about the equilibrium point at B≥0 and the equilibrium point is the center point of the system at B=0. Finally, the phase diagrams of global topological structure of HHV system were entirely described according to qualitative analysis of the singular points at infinity. 展开更多
关键词 automotive engineering hydraulic hybrid vehicle limit cycle global structure
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部