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混沌序列网形跳频网络同步方案 被引量:1
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作者 曹华 盛利元 +1 位作者 刘爱惠 张占锋 《火力与指挥控制》 CSCD 北大核心 2011年第9期9-13,18,共6页
跳频信号的同步过程是跳频通信系统的关键。针对网形跳频网络中同步难的问题,提出了一种基于混沌序列的动态双频跳频同步方案。该方案采用混沌系统生成分布式跳频序列,同时引入并行解调器结构实现双频跳变的时序控制。仿真结果表明,方... 跳频信号的同步过程是跳频通信系统的关键。针对网形跳频网络中同步难的问题,提出了一种基于混沌序列的动态双频跳频同步方案。该方案采用混沌系统生成分布式跳频序列,同时引入并行解调器结构实现双频跳变的时序控制。仿真结果表明,方案可有效应对慢跳频通信系统中常见的部分频带干扰和强单频干扰,且同步建立过程简单迅速,系统的稳定性和安全性好。 展开更多
关键词 混沌序列 同步 双频跳频 网形网
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多层聚酯成形网加强清洗的基本方法
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作者 李东日 《黑龙江造纸》 2008年第1期60-61,共2页
结合生产实践总结了多层聚酯成形网在使用中应该注意的问题,对如何加强洗涤,提高清洗效果,延长多层聚酯成形网使用寿命提出了建议。
关键词 多层聚酯成(简称成) 喷水管 喷嘴 洗涤用水
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战术通信网抗毁性量度与分析
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作者 杜国新 王康年 赵建伟 《重庆通信学院学报》 2001年第2期51-55,共5页
本文讨论了战术通信网的抗毁性量度,分析了战术通信网拓扑结构和传输链路的抗毁特性,为采用抗毁对策提供依据。
关键词 战术通信 抗毁性 拓扑结构 链路 网形网 拓扑结构
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浅谈SDH在GSM-R移动通信系统中的应用
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作者 骆友曾 《中国新通信》 2009年第9期60-63,共4页
本文介绍了SDH网络拓扑结构和常见的网络保护方式,并结合客运专线的业务需求提出了适合于GSM-R移动通信系统的组网方案。
关键词 GSM—R SDH ASON SNCP MSP PP 网形网 LMSP
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Edge span of L(d,1)-labeling on some graphs
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作者 冯桂珍 宋增民 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期111-114,共4页
Given a graph G and a positive integer d, an L( d, 1) -labeling of G is afunction / that assigns to each vertex of G a non-negative integer such that |f(u)-f (v) | >=d ifd_c(u, v) =1;|f(u)-f(v) | >=1 if d_c(u, v... Given a graph G and a positive integer d, an L( d, 1) -labeling of G is afunction / that assigns to each vertex of G a non-negative integer such that |f(u)-f (v) | >=d ifd_c(u, v) =1;|f(u)-f(v) | >=1 if d_c(u, v) =2. The L(d, 1)-labeling number of G, lambda_d(G) is theminimum range span of labels over all such labelings, which is motivated by the channel assignmentproblem. We consider the question of finding the minimum edge span beta_d( G) of this labeling.Several classes of graphs such as cycles, trees, complete k-partite graphs, chordal graphs includingtriangular lattice and square lattice which are important to a telecommunication problem arestudied, and exact values are given. 展开更多
关键词 L(d 1)-labeling edge span triangular lattice square lattice choralgraphs r-path
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Design for CNN Templates with Performance of Global Connectivity Detection 被引量:9
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作者 LIUJin-Zhu MINLe-Quan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第1期151-156,共6页
The cellular neural/nonlinear network (CNN) is a powerful tool for image and video signal processing,robotic and biological visions. This paper discusses a general method for designing template of the global connectiv... The cellular neural/nonlinear network (CNN) is a powerful tool for image and video signal processing,robotic and biological visions. This paper discusses a general method for designing template of the global connectivitydetection (GCD) CNN, which provides parameter inequalities for determining parameter intervals for implementing thecorresponding functions. The GCD CNN has stronger ability and faster rate for determining global connectivity in binarypatterns than the GCD CNN proposed by Zarandy. An example for detecting the connectivity in complex patterns isgiven. 展开更多
关键词 cellular neural network global connectivity detection template parameters
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Strategic games on a hierarchical network model 被引量:2
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作者 Yi-xiao LI Xiao-gang JIN +1 位作者 Fan-sheng KONG Hui-lan LUO 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第2期271-278,共8页
Among complex network models,the hierarchical network model is the one most close to such real networks as world trade web,metabolic network,WWW,actor network,and so on.It has not only the property of power-law degree... Among complex network models,the hierarchical network model is the one most close to such real networks as world trade web,metabolic network,WWW,actor network,and so on.It has not only the property of power-law degree distribution,but also the scaling clustering coefficient property which Barabási-Albert(BA)model does not have.BA model is a model of network growth based on growth and preferential attachment,showing the scale-free degree distribution property.In this paper,we study the evolution of cooperation on a hierarchical network model,adopting the prisoner's dilemma(PD)game and snowdrift game(SG)as metaphors of the interplay between connected nodes.BA model provides a unifying framework for the emergence of cooperation.But interestingly,we found that on hierarchical model,there is no sign of cooperation for PD game,while the fre-quency of cooperation decreases as the common benefit decreases for SG.By comparing the scaling clustering coefficient prop-erties of the hierarchical network model with that of BA model,we found that the former amplifies the effect of hubs.Considering different performances of PD game and SG on complex network,we also found that common benefit leads to cooperation in the evolution.Thus our study may shed light on the emergence of cooperation in both natural and social environments. 展开更多
关键词 Complex network Hierarchical network model Barabási-Albert (BA) model Prisoner's dilemma (PD) game Snowdrift game (SG)
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Equality Testing for Soil Grid Unit Resolutions to Polygon Unit Scales with DNDC Modeling of Regional SOC Pools 被引量:2
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作者 YU Dongsheng PAN Yue +4 位作者 ZHANG Haidong WANG Xiyang NI Yunlong ZHANG Liming SHI Xue-zheng 《Chinese Geographical Science》 SCIE CSCD 2017年第4期552-568,共17页
Matching soil grid unit resolutions with polygon unit map scales is important to minimize the uncertainty of regional soil organic carbon(SOC) pool simulation due to their strong influences on the modeling.A series of... Matching soil grid unit resolutions with polygon unit map scales is important to minimize the uncertainty of regional soil organic carbon(SOC) pool simulation due to their strong influences on the modeling.A series of soil grid units at varying cell sizes was derived from soil polygon units at six map scales,namely,1:50 000(C5),1:200 000(D2),1:500 000(P5),1:1 000 000(N1),1:4 000 000(N4) and 1:14 000 000(N14),in the Taihu Region of China.Both soil unit formats were used for regional SOC pool simulation with a De Nitrification-DeC omposition(DNDC) process-based model,which spans the time period from 1982 to 2000 at the six map scales.Four indices,namely,soil type number(STN),area(AREA),average SOC density(ASOCD) and total SOC stocks(SOCS) of surface paddy soils that were simulated by the DNDC,were distinguished from all these soil polygon and grid units.Subjecting to the four index values(IV) from the parent polygon units,the variations in an index value(VIV,%) from the grid units were used to assess its dataset accuracy and redundancy,which reflects the uncertainty in the simulation of SOC pools.Optimal soil grid unit resolutions were generated and suggested for the DNDC simulation of regional SOC pools,matching their respective soil polygon unit map scales.With these optimal raster resolutions,the soil grid units datasets can have the same accuracy as their parent polygon units datasets without any redundancy,when VIV < 1% was assumed to be a criterion for all four indices.A quadratic curve regression model,namely,y = – 0.80 × 10^(–6)x^2 + 0.0228 x + 0.0211(R^2 = 0.9994,P < 0.05),and a power function model R? = 10.394?^(0.2153)(R^2 = 0.9759,P < 0.05) were revealed,which describe the relationship between the optimal soil grid unit resolution(y,km) and soil polygon unit map scale(1:10 000x),the ratio(R?,%) of the optimal soil grid size to average polygon patch size(?,km^2) and the ?,with the highest R^2 among different mathematical regressions,respectively.This knowledge may facilitate the grid partitioning of regions during the investigation and simulation of SOC pool dynamics at a certain map scale,and be referenced to other landscape polygon patches' mesh partition. 展开更多
关键词 soil organic carbon(SOC) soil grid unit resolutions soil polygon unit map scales DeNitrification-DeComposition(DNDC) model SOC pools
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Storage capacity of complex Hopfield model
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作者 SHUAI J W CHEW Z X +1 位作者 LIU R T WU B X(Dept.of Physics,Xiamen University,Xiamen 361005,CHN) 《Semiconductor Photonics and Technology》 CAS 1995年第1期35-42,共8页
The Dirac symbol is used to represent the discrete complex Hopfield neural network model.The signal-to-noise theory and the computer numerical solution are made to analyse the storage capacity of the model.The storage... The Dirac symbol is used to represent the discrete complex Hopfield neural network model.The signal-to-noise theory and the computer numerical solution are made to analyse the storage capacity of the model.The storage capacity ratio of the model equals to that of the Hopfield model.Finally,using the model to recognize the 4-level grey or color patterns is discussed. 展开更多
关键词 Neural Nets Computer Networks Pattern Recognition NEURONS
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Positioning of grid points in wave front construction 被引量:6
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作者 Han Fuxing Sun Jianguo +1 位作者 Sun Zhangqing Yang Hao 《Applied Geophysics》 SCIE CSCD 2009年第3期248-258,300,共12页
In view of the relative positioning problem between non-regular quadrilateral grids and regular rectangle grid nodes in the wave front construction method, concrete realization problems with four grid positioning meth... In view of the relative positioning problem between non-regular quadrilateral grids and regular rectangle grid nodes in the wave front construction method, concrete realization problems with four grid positioning methods (vector cross product judgment, angle sum, intersection-point, and signs comparison algorithms) in wave front construction which are commonly used in computer graphics are compared and analyzed in this paper. Based on the stability analysis of the location method, the calculation examples show that the vector cross product judgment method is faster and more accurate than other methods in the realization of the relative positioning between non-regular quadrilateral grids and regular rectangle grid nodes in wave front construction. It provides precise grid point attribute values for the next steps of migration and demigration. 展开更多
关键词 wave front construction grid localization grid nodes wave front quadrilateral
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Estimation of Data Transfer Routes Fractal Dimension in Large Scale Networks
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作者 Yuriy Danik Yuriy Kulakov +1 位作者 Vladimir Vorotnikov Igor Gumenyuk 《Journal of Mathematics and System Science》 2016年第1期38-45,共8页
The article is devoted to the evaluation of fractal properties of routing data in computer large scale networks. Implemented the study of percolation network topological structures of large dimension and made their tr... The article is devoted to the evaluation of fractal properties of routing data in computer large scale networks. Implemented the study of percolation network topological structures of large dimension and made their transformation into fractal macrostructure. An example of calculating the fractal dimension of the data path for the boundary of the phase transition between the states of network connectivity. The dependence of the fractal dimension of the percolation cluster on the size of the square δ-cover and conductivity value network of large dimension. It is shown that for the value of the fractal dimension of the route dc ≈ 1.5, network has a stable dynamics of development and size of clusters are optimized with respect to the current load on the network. 展开更多
关键词 large scale network percolation cluster fractal dimension ROUTING
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Relationships Between Fractal Road and Drainage Networks in Wuling Mountainous Area:Another Symmetric Understanding of Human-Environment Relations 被引量:2
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作者 LIU Cheng-liang DUAN De-zhong ZHANG Hong 《Journal of Mountain Science》 SCIE CSCD 2014年第4期1060-1069,共10页
Symmetrical relationships between humans and their environment have been referred to as an extension of symmetries in the human geographical system and have drawn great attention. This paper explored the symmetry betw... Symmetrical relationships between humans and their environment have been referred to as an extension of symmetries in the human geographical system and have drawn great attention. This paper explored the symmetry between physical and human systems through fractal analysis of the road and drainage networks in Wuling mountainous area. We found that both the road and drainage networks reflect weak clustering distributions. The evolution of the road network shared a significant self-organizing composition, while the drainage network showed obvious double fraetal characteristics. The geometric fractal dimension of the road network was larger than that of the drainage network. In addition, when assigned a weight relating to hierarchy or length, neither the road network nor drainage network showed a fractal property. These findings indicated that the fractal evolution of the road network shared certain similarities with fractal distribution of the drainage network. The symmetry between the two systems resulted from an interactive process of destroying symmetry at the lower order and reconstructing symmetry at the higher order. The relationships between the fractal dimensions of the rural-urban road network, the drainage network andthe urban system indicated that the development of this area was to achieve the symmetrical isomorphism of physical-human geographical systems. 展开更多
关键词 Fractal road network Fractal drainagenetwork SYMMETRY Human-environment relation SELF-ORGANIZATION
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A General Study on Equivalent Resistance of Three-Terminal Ladder Network
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作者 WuGuoxiang TanZhizhong +1 位作者 SongGuohua SongChangqing 《Electricity》 2005年第1期38-40,共3页
In view of the application importance of resistance network in modern science and technology, this paper presents the basic structure of a three terminals ladder shaped resistance network, for which, to study in- dept... In view of the application importance of resistance network in modern science and technology, this paper presents the basic structure of a three terminals ladder shaped resistance network, for which, to study in- depth the equivalent resistance, carry out network analysis by applying virtual current method and construct a model of two elements three orders differential equation. Based on different marginal conditions, two general adaptive rules for the three-terminal ladder shaped inlet resistance, as well as two ultimate rules for the equiva- lent resistance of three-terminal infinite ladder shaped were given. 展开更多
关键词 three-terminal network virtual current equivalent resistance
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Research and Monitoring of Metro Tunnel Deformation based on the Technology of the Internet of Things
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作者 Xiaowei Du Yongtao Gao 《International Journal of Technology Management》 2013年第1期11-13,共3页
After a long subway tunnel operators will produce cross-sectional deformation. Articles designed vehicle laser ranging device tbr continuous measurement of tunnel wall to test their defomaed state. The paper also desc... After a long subway tunnel operators will produce cross-sectional deformation. Articles designed vehicle laser ranging device tbr continuous measurement of tunnel wall to test their defomaed state. The paper also describes the tunnel cross-section deltbrmation measurement method, contour titting principles and error analysis and networking technology for wireless data transmission methods. The detection system is designed to achieve a tunnel section of the structural safety testing and deformation that may occur timely disaster warning, the safe operation of the subway tunnel to provide effective protection. 展开更多
关键词 Internet of Things technology sectional defom^ation laser rangefinder
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Study of blood sugar concentration based on serum UV absorption spectra*
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作者 ZHU Wei-hua ZHAO Zhi-min +2 位作者 GUO Xin WANG Le-xin CHEN Hui 《Journal of Life Sciences》 2008年第1期62-66,共5页
UV absorption spectrum and neural network theory was used for the analysis of blood sugar concentration. Experimental investigation shows that absorption spectrum has the following characteristics in the wave band of ... UV absorption spectrum and neural network theory was used for the analysis of blood sugar concentration. Experimental investigation shows that absorption spectrum has the following characteristics in the wave band of 200-300 nm: (1) The absorption spectrum is of complex shape, there is more absorption peak in UV-band, it shows that there is a complex absorption phenomenon in blood group macromolecules; (2) The curve shapes of absorption spectra are similar to different samples ,the reason is that the spectrum is synthesis of some group macromolecules absorption spectrum; (3) There is a degree of displacement of absorption peak to different samples; (4) There is no significant correlation between absorbance and blood sugar concentration at 278 nm, but random. Based on the wave band of 280 nm to 300 nm, a neural network model was built to determine the blood sugar concentration. 展开更多
关键词 blood sugar concentration UV absorptionspectrum Neural Network (NN) SERUM
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EQ_1^(rot) nonconforming finite element approximation to Signorini problem 被引量:16
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作者 SHI DongYang XU Chao 《Science China Mathematics》 SCIE 2013年第6期1301-1311,共11页
Abstract In this paper, we apply EQ1^rot nonconforming finite element to approximate Signorini problem. If 5 the exact solution u EQ1^rot, the error estimate of order O(h) about the broken energy norm is obtained f... Abstract In this paper, we apply EQ1^rot nonconforming finite element to approximate Signorini problem. If 5 the exact solution u EQ1^rot, the error estimate of order O(h) about the broken energy norm is obtained for quadrilateral meshes satisfying regularity assumption and bi-section condition. Furthermore, the superconver- gence results of order EQ1^rot are derived for rectangular meshes. Numerical results are presented to confirm the considered theory. 展开更多
关键词 Signorini problem nonconforming finite element SUPERCONVERGENCE error estimate
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The effect of grid shape on the properties of transparent conductive films based on flexographic printing 被引量:2
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作者 LIU Wei FANG Yi +2 位作者 XU Yan Fang LI Xiu LI Lu Hai 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第12期2536-2541,共6页
The effect of grid shape on the properties of transparent conductive films(TCFs) is theoretically analyzed and experimentally verified. The light transmittance by three types of grid shapes: triangle, square and hexag... The effect of grid shape on the properties of transparent conductive films(TCFs) is theoretically analyzed and experimentally verified. The light transmittance by three types of grid shapes: triangle, square and hexagon have been theoretically calculated and simulated. It was found that hexagonal grid unit has the highest light transmittance limit under the practical lattice parameters and its decrease in light transmittance caused by the increase of line width in printing process is the least. The grid of three different shapes with same theoretical transmittance is fabricated through flexographic printing. The result shows that the actual light transmittance of the printed TCFs is lower than its theoretical value because of the inevitable width increase of printed grid lines, with slight difference between the three shapes. However, it is greatly different in terms of conductivity, leading to variation in the quality factor Q(defined as the ratio of light transmittance to total resistance) which represents the performance of TCFs. The Q of hexagonal grid(6.04) is the highest, which is 21% higher than that of the square grid. 展开更多
关键词 metal grid transparent conductive films flexographic printing grid shape quality factor Q
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A fast mapping method to evaluate immersed boundary hydrodynamic forces
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作者 Shi-Jun Li Jun-Hua Pan Ming-Jiu Ni 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2022年第8期49-57,共9页
Immersed boundary method is a crucial method to deal with particle suspension flow.Particle shapes involved in such flow are usually simple geometry,such as sphere and ellipsoid,which can be conveniently represented b... Immersed boundary method is a crucial method to deal with particle suspension flow.Particle shapes involved in such flow are usually simple geometry,such as sphere and ellipsoid,which can be conveniently represented by the triangular surface grid.When the number of particles and resolution of the surface grid increase,calculating the hydrodynamic force on the particle surface through integration can be time-consuming.Hence,the present paper establishes a fast mapping method to evaluate immersed boundary hydrodynamic force.Firstly,the particle surface grid is generated by an initial triangular element grid.Subsequently,the initial surface grid is refined by bisection refinement to the desired resolution.The final step is to find the triangular element index on the particle triangular surface grid,which contains the projective point.Test cases show that the present mapping algorithm has good accuracy and efficiency for calculating hydrodynamic forces of particles. 展开更多
关键词 Hydrodynamic force Immersed boundary method Particle suspensions Mapping algorithm
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Surface remeshing with robust user-guided segmentation
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作者 Dawar Khan Dong-Ming Yan +2 位作者 Fan Ding Yixin Zhuang Xiaopeng Zhang 《Computational Visual Media》 CSCD 2018年第2期113-122,共10页
Surface remeshing is widely required in modeling, animation, simulation, and many other computer graphics applications. Improving the elements' quality is a challenging task in surface remeshing. Existing methods ... Surface remeshing is widely required in modeling, animation, simulation, and many other computer graphics applications. Improving the elements' quality is a challenging task in surface remeshing. Existing methods often fail to efficiently remove poor-quality elements especially in regions with sharp features. In this paper, we propose and use a robust segmentation method followed by remeshing the segmented mesh. Mesh segmentation is initiated using an existing Live-wire interaction approach and is further refined using local mesh operations. The refined segmented mesh is finally sent to the remeshing pipeline, in which each mesh segment is remeshed independently. An experimental study compares our mesh segmentation method as well as remeshing results with representative existing methods. We demonstrate that the proposed segmentation method is robust and suitable for remeshing. 展开更多
关键词 mesh generation surface remeshing mesh segmentation triangulation
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Adaptive triangular mesh coarsening with centroidal Voronoi tessellations 被引量:2
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作者 Zhen-yu SHU Guo-zhao WANG Chen-shi DONG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第4期535-545,共11页
We present a novel algorithm for adaptive triangular mesh coarsening. The algorithm has two stages. First, the input triangular mesh is refined by iteratively applying the adaptive subdivision operator that performs a... We present a novel algorithm for adaptive triangular mesh coarsening. The algorithm has two stages. First, the input triangular mesh is refined by iteratively applying the adaptive subdivision operator that performs a so-called red-green split. Second, the refined mesh is simplified by a clustering algorithm based on centroidal Voronoi tessellations (CVTs). The accuracy and good quality of the output triangular mesh are achieved by combining adaptive subdivision and the CVTs technique. Test results showed the mesh coarsening scheme to be robust and effective. Examples are shown that validate the method. 展开更多
关键词 Triangular mesh Mesh coarsening Surface subdivision Centroidal Voronoi tessellations (CVTs)
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