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确定裂陷盆地伸展量的分数维法 被引量:3
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作者 任建业 张俊霞 《地质科技情报》 CAS CSCD 北大核心 1997年第3期102-106,共5页
脆性断层群落的位移具有分数维特征,此特征可以用于建立一种裂陷盆地伸展量估算的新方法,即分数维法。这种方法可以用于确定在地震反射剖面上不可测定的小型断层之上滑移造成的伸展量大小,计算结果可以弥合不同计算方法之间的差异,... 脆性断层群落的位移具有分数维特征,此特征可以用于建立一种裂陷盆地伸展量估算的新方法,即分数维法。这种方法可以用于确定在地震反射剖面上不可测定的小型断层之上滑移造成的伸展量大小,计算结果可以弥合不同计算方法之间的差异,阐明小型断层在区域裂陷作用变形过程中的重要意义。以二连断陷盆地群伸展量的确定为例,详细地介绍了这种方法的使用原理和步骤。 展开更多
关键词 裂陷盆地 分数维法 水平伸展量 盆地
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微粉颗粒形貌特征表征新方法—分数维
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作者 董学仁 张大勇 《建材新科技》 1997年第1期32-33,36,共3页
关键词 微粉颗粒形貌 分数维法 粉末技术 颗粒学
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混凝土粘结面粗糙度测试方法研究 被引量:5
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作者 张启明 张雷顺 《河南科学》 2002年第4期411-413,共3页
通过 30组混凝土立方体试块 ,分别对人工凿毛及劈拉试验试件的断开面两种类型分别采用自制量测仪法与灌砂法进行了粘结面粗糙度测试研究。给出了两种量测方法测试混凝土粘结面粗糙度回归公式且具有较好的相关性。该量测仪操作简单、使... 通过 30组混凝土立方体试块 ,分别对人工凿毛及劈拉试验试件的断开面两种类型分别采用自制量测仪法与灌砂法进行了粘结面粗糙度测试研究。给出了两种量测方法测试混凝土粘结面粗糙度回归公式且具有较好的相关性。该量测仪操作简单、使用方便、造价低 ,特别适合实际工程加固中混凝土粘结面粗糙度测量 ,为工程加固中提供了一种好的混凝土粘结面粗糙度测试方法。 展开更多
关键词 混凝土粘结面 粗糙度 测试方 混凝土结构 结构加固 灌砂 分数维法
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Multi-Symplectic Splitting Method for Two-Dimensional Nonlinear Schrodinger Equation 被引量:2
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作者 陈亚铭 朱华君 宋松和 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第10期617-622,共6页
Using the idea of splitting numerical methods and the multi-symplectic methods, we propose a multisymplectic splitting (MSS) method to solve the two-dimensional nonlinear Schrodinger equation (2D-NLSE) in this pap... Using the idea of splitting numerical methods and the multi-symplectic methods, we propose a multisymplectic splitting (MSS) method to solve the two-dimensional nonlinear Schrodinger equation (2D-NLSE) in this paper. It is further shown that the method constructed in this way preserve the global symplectieity exactly. Numerical experiments for the plane wave solution and singular solution of the 2D-NLSE show the accuracy and effectiveness of the proposed method. 展开更多
关键词 splitting method multi-symplectic scheme two-dimensional nonlinear SchrSdinger equation
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Iterative Solution for Groundstate of H_2^+ Ion
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作者 刘庆军 赵维勤 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第1期57-62,共6页
To solve the wave functions and energies of the groundstate of H+2 ion an iteration procedure for N- dimensional potentials is applied. The iterative solutions are convergent nicely, which are comparable to earlier r... To solve the wave functions and energies of the groundstate of H+2 ion an iteration procedure for N- dimensional potentials is applied. The iterative solutions are convergent nicely, which are comparable to earlier results based on variational methods. 展开更多
关键词 iterative solution trial function H+2 groundstate
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Chaos Existence in Surface Discharge of Tracking Test
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作者 杜伯学 董典帅 郑晓磊 《Transactions of Tianjin University》 EI CAS 2009年第3期168-172,共5页
Tracking tests for different polymer materials were carried out to investigate the chaotic behavior of surface discharge. The discharge sequences measured during the discharge process were analyzed for finding the evi... Tracking tests for different polymer materials were carried out to investigate the chaotic behavior of surface discharge. The discharge sequences measured during the discharge process were analyzed for finding the evidence of chaos existence. Four kinds of nonlinear analysis methods were adopted: estimating the largest Lyapunov exponent, calculating the fractal dimension with increasing the embedding dimension, drawing the recurrence plots, and plotting the Poincare maps. It is found that the largest Lyapunov exponent of the discharge is positive, and the plot of fractal dimension, as a function of embedding dimension, will saturate at a value. The recur- rence plots show the chaotic frame-work patterns, and the Poincar6 maps also have the chaotic characteristics. The results indicate that the chaotic behavior does exist in the discharge currents of the tracking test. 展开更多
关键词 CHAOS Lyapunov exponent fractal dimension recurrence plot Poincare map TRACKING
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Discriminant embedding by sparse representation and nonparametric discriminant analysis for face recognition
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作者 杜春 周石琳 +2 位作者 孙即祥 孙浩 王亮亮 《Journal of Central South University》 SCIE EI CAS 2013年第12期3564-3572,共9页
A novel supervised dimensionality reduction algorithm, named discriminant embedding by sparse representation and nonparametric discriminant analysis(DESN), was proposed for face recognition. Within the framework of DE... A novel supervised dimensionality reduction algorithm, named discriminant embedding by sparse representation and nonparametric discriminant analysis(DESN), was proposed for face recognition. Within the framework of DESN, the sparse local scatter and multi-class nonparametric between-class scatter were exploited for within-class compactness and between-class separability description, respectively. These descriptions, inspired by sparse representation theory and nonparametric technique, are more discriminative in dealing with complex-distributed data. Furthermore, DESN seeks for the optimal projection matrix by simultaneously maximizing the nonparametric between-class scatter and minimizing the sparse local scatter. The use of Fisher discriminant analysis further boosts the discriminating power of DESN. The proposed DESN was applied to data visualization and face recognition tasks, and was tested extensively on the Wine, ORL, Yale and Extended Yale B databases. Experimental results show that DESN is helpful to visualize the structure of high-dimensional data sets, and the average face recognition rate of DESN is about 9.4%, higher than that of other algorithms. 展开更多
关键词 dimensionality reduction sparse representation nonparametric discriminant analysis
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Iris Feature Extraction and Recognition Based on Fractal Dimension of Grayscale Extremums
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作者 刘凯 周卫东 +1 位作者 王长宇 王玉 《Journal of Measurement Science and Instrumentation》 CAS 2011年第3期235-239,共5页
This paper presented an individual recognition algorithm for human iris using fractal dimension of grayscale extremums for feature extraction.Firstly,iris region was localized from an eye image with modified circle de... This paper presented an individual recognition algorithm for human iris using fractal dimension of grayscale extremums for feature extraction.Firstly,iris region was localized from an eye image with modified circle detector stemmed from Daugman’s integro-differential operator.Then,segmentation was used to extract the iris and to exclude occlusion from eyelids and eyelashes.The extracted iris was normalized and mapped to polar coordinates for matching.In feature encoding,a new approach based on fractal dimension of grayscale extremums was designed to extract textural features of iris.Finally,a normalized correlation classifier was employed to determine the agreement of two iris feature templates,and the feature template was rotated left and right to avoid the interference from rotation of eyes and tilting of head.The experimental results show that fractal dimension of grayscale extremums can extract textural features from iris image effectively,and the proposed recognition algorithm is accurate and efficient.The proposed algorithm was tested on CASIA-IrisV3-Interval iris database and the performance was evaluated based on the analysis of both False Accept Rate(FAR)and False Reject Rate(FRR)curves.Experimental results show that the proposed iris recognition algorithm is effective and efficient. 展开更多
关键词 iris recognition fractal dimension normalized correlation
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3D Multiphase Piecewise Constant Level Set Method Based on Graph Cut Minimization 被引量:2
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作者 Tiril P Gurholt Xuecheng Tai 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2009年第4期403-420,共18页
Segmentation of three-dimensional(3D) complicated structures is of great importance for many real applications.In this work we combine graph cut minimization method with a variant of the level set idea for 3D segmenta... Segmentation of three-dimensional(3D) complicated structures is of great importance for many real applications.In this work we combine graph cut minimization method with a variant of the level set idea for 3D segmentation based on the Mumford-Shah model.Compared with the traditional approach for solving the Euler-Lagrange equation we do not need to solve any partial differential equations.Instead,the minimum cut on a special designed graph need to be computed.The method is tested on data with complicated structures.It is rather stable with respect to initial value and the algorithm is nearly parameter free.Experiments show that it can solve large problems much faster than traditional approaches. 展开更多
关键词 Piecewise constant level set method energy minimization graph cut SEGMENTATION three-dimensional.
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Flow Label-Based TPv6 Packet Classification Algorithm with Dimension Reduction Capability
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作者 黄小红 马严 《China Communications》 SCIE CSCD 2012年第5期1-9,共9页
Traditional packet classification for IPv4 involves examining standard 5-tuple of a packet header, source address, destination address, source port, destination port and protocol. With introduction of IPv6 flow label ... Traditional packet classification for IPv4 involves examining standard 5-tuple of a packet header, source address, destination address, source port, destination port and protocol. With introduction of IPv6 flow label field which entails labeling the packets belonging to the same flow, packet classification can be resolved based on 3 dimensions: flow label, source address and desti- nation address. In this paper, we propose a novel approach for the 3-tuple packet classification based on flow label. Besides, by introducing a conversion engine to covert the source-destination pairs to the compound address prefixes, we put forward an algorithm called Reducing Dimension (RD) with dimension reduction capability, which combines heuristic tree search with usage of buck- ets. And we also provide an improved version of RD, called Improved RD (IRD), which uses two mechanisms: path compression and priority tag, to optimize the perforrmnce. To evaluate our algo- rithm, extensive experiraents have been conducted using a number of synthetically generated databas- es. For the memory consumption, the two pro- posed new algorithms only consumes around 3% of the existing algorithms when the number of ill- ters increases to 10 k. And for the average search time, the search time of the two proposed algo- rithms is more than four times faster than others when the number of filters is 10 k. The results show that the proposed algorithm works well and outperforms rmny typical existing algorithms with the dimension reduction capability. 展开更多
关键词 IPV6 packet classification flow label
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3D stability analysis method of concave slope based on the Bishop method 被引量:6
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作者 Zhang Tianwen Cai Qingxiang +2 位作者 Han Liu Shu Jisen Zhou Wei 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第2期365-370,共6页
In order to study the stability control mechanism of a concave slope with circular landslide, and remove the influence of differences in shape on slope stability, the limit analysis method of a simplified Bishop metho... In order to study the stability control mechanism of a concave slope with circular landslide, and remove the influence of differences in shape on slope stability, the limit analysis method of a simplified Bishop method was employed. The sliding body was divided into strips in a three-dimensional model, and the lateral earth pressure was put into mechanical analysis and the three-dimensional stability analysis methods applicable for circular sliding in concave slope were deduced. Based on geometric structure and the geological parameters of a concave slope, the influence rule of curvature radius and the top and bottom arch height on the concave slope stability were analyzed. The results show that the stability coefficient decreases after growth, first in the transition stage of slope shape from flat to concave, and it has been confirmed that there is a best size to make the slope stability factor reach a maximum. By contrast with average slope, the stability of a concave slope features a smaller range of ascension with slope height increase, which indicates that the enhancing effect of a concave slope is apparent only with lower slope heights. 展开更多
关键词 Bishop method Concave slope Three-dimensional structure Stability analysis
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Effect of Gravity on Collective Excitations of a Quasi Two-Dimensional Bose Einstein Condensate in an Anharmonic Trap
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作者 P.D.Anoop Ramesh Babu Thayyullathil 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第10期669-671,共3页
Abstract Using variational method, the wave function of a quasi two-dimensional Bose-Einstein Condensate in an anharmonic trap is analyzed and the influence of gravity on the eollective excitations is studied. It is f... Abstract Using variational method, the wave function of a quasi two-dimensional Bose-Einstein Condensate in an anharmonic trap is analyzed and the influence of gravity on the eollective excitations is studied. It is found that the effect of gravity on the condensate has got crucial dependence on the anharmonieity of the trap. 展开更多
关键词 Bose-Einstein condensation variational method collective excitations
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Relationship between critical seismic acceleration coefficient and static factor of safety of 3D slopes
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作者 SHI He-yang CHEN Guang-hui 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第5期1546-1554,共9页
Many analytical methods have been adopted to estimate the slope stability by providing various stability numbers,e.g.static safety of factor(static FoS)or the critical seismic acceleration coefficient,while little att... Many analytical methods have been adopted to estimate the slope stability by providing various stability numbers,e.g.static safety of factor(static FoS)or the critical seismic acceleration coefficient,while little attention has been given to the relationship between the slope stability numbers and the critical seismic acceleration coefficient.This study aims to investigate the relationship between the static FoS and the critical seismic acceleration coefficient of soil slopes in the framework of the upper-bound limit analysis.Based on the 3D rotational failure mechanism,the critical seismic acceleration coefficient using the pseudo-static method and the static FoS using the strength reduction technique are first determined.Then,the relationship between the static FoS and the critical seismic acceleration coefficient is presented under considering the slope angleβ,the frictional angleφ,and the dimensionless coefficients B/H and c/γH.Finally,a fitting formula between the static FoS and the critical seismic acceleration coefficient is proposed and validated by analytical and numerical results. 展开更多
关键词 static safety of factor critical seismic acceleration coefficient upper-bound limit analysis 3D rotational failure mechanism
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Analytical Investigation of Soliton Solutions to Three Quantum Zakharov-Kuznetsov Equations 被引量:2
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作者 Rahmatullah Ibrahim Nuruddeen Khalid Suliman Aboodh Khalid K. Ali 《Communications in Theoretical Physics》 SCIE CAS CSCD 2018年第10期405-412,共8页
In the present paper, the two-dimensional quantum Zakharov-Kuznetsov(QZK) equation, three-dimensional quantum Zakharov-Kuznetsov equation and the three-dimensional modified quantum Zakharov-Kuznetsov equation are anal... In the present paper, the two-dimensional quantum Zakharov-Kuznetsov(QZK) equation, three-dimensional quantum Zakharov-Kuznetsov equation and the three-dimensional modified quantum Zakharov-Kuznetsov equation are analytically investigated for exact solutions using the modified extended tanh-expansion based method. A variety of new and important soliton solutions are obtained including the dark soliton solution, singular soliton solution, combined dark-singular soliton solution and many other trigonometric function solutions. The used method is implemented on the Mathematica software for the computations as well as the graphical illustrations. 展开更多
关键词 two-dimensional QZK equation three-dimensional QZK equations soliton solutions
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CLASSIFICATION OF AF-ALGEBRAS AND THEIR DIMENSION GROUPS
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作者 HUANG ZHAOBO(Institute of Mathematics, Fudan University, Shanghai 200433, Shanghai, China) 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1994年第2期181-192,共12页
This paper gives the intrinsic character of the classification for AF-algebras defined by J.Cuntz and G. K. Pedersen in terms of their dimension groups.
关键词 AF-algebra Demension group Classification.
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Influences of Fractal Substrate Structures on Dynamic Scaling Behaviors of Etching Model
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作者 宋丽建 唐刚 +3 位作者 寻之朋 郝大鹏 陈祎力 张哲 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第10期471-477,共7页
The Etching model on various fractal substrates embedded in two dimensions was investigated by means of kinetic Mento Carlo method in order to determine the relationship between dynamic scaling exponents and fractal p... The Etching model on various fractal substrates embedded in two dimensions was investigated by means of kinetic Mento Carlo method in order to determine the relationship between dynamic scaling exponents and fractal parameters. The fractal dimensions are from 1.465 to 1.893, and the random walk exponents are from 2.101 to 2.578.It is found that the dynamic behaviors on fractal lattices are more complex than those on integer dimensions. The roughness exponent increases with the increasing of the random walk exponent on the fractal substrates but shows a non-monotonic relation with respect to the fractal dimension. No monotonic change is observed in the growth exponent. 展开更多
关键词 Etching model fractal substrates dynamic scaling
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The four dimensional variational data assimilation with multiple regularization parameters as a weak constraint(Tikh-4D-Var) and its preliminary application on typhoon initialization
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作者 ZHONG Jian FEI JianFang +1 位作者 CHENG XiaoPing HUANG XiaoGang 《Science China Earth Sciences》 SCIE EI CAS 2014年第11期2690-2701,共12页
Traditional variational data assimilation (VDA) with only one regularization parameter constraint cannot produce optimal error tuning for all observations. In this paper, a new data assimilation method of "four dim... Traditional variational data assimilation (VDA) with only one regularization parameter constraint cannot produce optimal error tuning for all observations. In this paper, a new data assimilation method of "four dimensional variational data assimilation (4D-Var) with multiple regularization parameters as a weak constraint (Tikh-4D-Var)" is proposed by imposing different reg- ularization parameters for different observations. Meanwhile, a new multiple regularization parameters selection method, which is suitable for actual high-dimensional data assimilation system, is proposed based on the posterior information of 4D-Var system. Compared with the traditional single regularization parameter selection method, computation of the proposed multiple regularization parameters selection method is smaller. Based on WRF3.3.1 4D-Vat data assimilation system, initiali- zation and simulation of typhoon Chaba (2010) with the new Tikh-4D-Var method are compared with its counterpart 4D-Var to demonstrate the effectiveness of the new method. Results show that the new Tikh-4D-Var method can accelerate the con vergence with less iterations. Moreover, compared with 4D-Var method, the typhoon track, intensity (including center surface pressure and maximum wind speed) and structure prediction are obviously improved with Tikh-4D-Var method for 72-h pre- diction. In addition, the accuracy of the observation error variances can be reflected by the multiple regularization parameters. 展开更多
关键词 multiple regularization parameters 4D-VAR typhoon initialization
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Fractal characteristics of far-field diffraction patterns for two-dimensional Thue-Morse quasicrystals
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作者 阳明仰 周骏 +2 位作者 L Petti S De Nicola P Mormile 《Optoelectronics Letters》 EI 2011年第5期346-349,共4页
We report a numerical method to analyze the fractal characteristics of far-field diffraction patterns for two-dimensional Thue-Morse (2-D TM) structures. The far-field diffraction patterns of the 2-D TM structures can... We report a numerical method to analyze the fractal characteristics of far-field diffraction patterns for two-dimensional Thue-Morse (2-D TM) structures. The far-field diffraction patterns of the 2-D TM structures can be obtained by the numerical method, and they have a good agreement with the experimental ones. The analysis shows that the fractal characteristics of far-field diffraction patterns for the 2-D TM structures are determined by the inflation rule, which have potential applications in the design of optical diffraction devices. 展开更多
关键词 Diffraction patterns Fractals INTERFEROMETRY Two dimensional
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Approximate Solutions of Nonlinear Fractional Kolmogorov-Petrovskii-Piskunov Equations Using an Enhanced Algorithm of the Generalized Two-Dimensional Differential Transform Method
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作者 宋丽哪 王维国 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第8期182-188,共7页
By constructing the iterative formula with a so-called convergence-control parameter, the generalized two-dimensional differential transform method is improved. With the enhanced technique, the nonlinear fractional Ko... By constructing the iterative formula with a so-called convergence-control parameter, the generalized two-dimensional differential transform method is improved. With the enhanced technique, the nonlinear fractional Kolmogorov-Petrovskii-Piskunov equations are dealt analytically and approximate solutions are derived. The results show that the employed approach is a promising tool for solving many nonlinear fractional partial differential equations. The algorithm described in this work is expected to be employed to solve more problems in fractional calculus. 展开更多
关键词 differential transform method fractional differential equation approximate solution
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Self-similar fractals: An algorithmic point of view
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作者 WANG Qin XI LiFeng ZHANG Kai 《Science China Mathematics》 SCIE 2014年第4期755-766,共12页
This paper studies the self-similar fractals with overlaps from an algorithmic point of view.A decidable problem is a question such that there is an algorithm to answer"yes"or"no"to the question fo... This paper studies the self-similar fractals with overlaps from an algorithmic point of view.A decidable problem is a question such that there is an algorithm to answer"yes"or"no"to the question for every possible input.For a classical class of self-similar sets{E b.d}b,d where E b.d=Sn i=1(E b,d/d+b i)with b=(b1,...,b n)∈Qn and d∈N∩[n,∞),we prove that the following problems on the class are decidable:To test if the Hausdorff dimension of a given self-similar set is equal to its similarity dimension,and to test if a given self-similar set satisfies the open set condition(or the strong separation condition).In fact,based on graph algorithm,there are polynomial time algorithms for the above decidable problem. 展开更多
关键词 FRACTAL DECIDABILITY DIMENSION separation condition
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