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The effect of gravity on self-similarity of Worthington jet after water entry of a two-dimensional wedge 被引量:2
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作者 Yan Du Jingzhu Wang +1 位作者 Zhiying Wang Yiwei Wang 《Theoretical & Applied Mechanics Letters》 CSCD 2023年第5期382-386,共5页
The effect of gravity on the self-similarity of jet shape at late stage of Worthington jet development is investigated by experiment in the study.In addition,the particle image velocimetry(PIV)method is introduced to ... The effect of gravity on the self-similarity of jet shape at late stage of Worthington jet development is investigated by experiment in the study.In addition,the particle image velocimetry(PIV)method is introduced to analyze the development of flow field.There is a linear scaling regarding the axial velocity of the jet and the scaling coefficient increases with the Froude number. 展开更多
关键词 Wortington jet self-similarity Jet shape PIV
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Self-similarity of complex networks under centrality-based node removal strategy
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作者 陈单 蔡德福 苏厚胜 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期596-602,共7页
Real-world networks exhibit complex topological interactions that pose a significant computational challenge to analyses of such networks.Due to limited resources,there is an urgent need to develop dimensionality redu... Real-world networks exhibit complex topological interactions that pose a significant computational challenge to analyses of such networks.Due to limited resources,there is an urgent need to develop dimensionality reduction techniques that can significantly reduce the structural complexity of initial large-scale networks.In this paper,we propose a subgraph extraction method based on the node centrality measure to reduce the size of the initial network topology.Specifically,nodes with smaller centrality value are removed from the initial network to obtain a subgraph with a smaller size.Our results demonstrate that various real-world networks,including power grids,technology,transportation,biology,social,and language networks,exhibit self-similarity behavior during the reduction process.The present results reveal the selfsimilarity and scale invariance of real-world networks from a different perspective and also provide an effective guide for simplifying the topology of large-scale networks. 展开更多
关键词 complex networks subgraph extraction self-similarity scale invariance
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The Golden Ratio Theorem: A Framework for Interchangeability and Self-Similarity in Complex Systems
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作者 Alessandro Rizzo 《Advances in Pure Mathematics》 2023年第9期559-596,共38页
The Golden Ratio Theorem, deeply rooted in fractal mathematics, presents a pioneering perspective on deciphering complex systems. It draws a profound connection between the principles of interchangeability, self-simil... The Golden Ratio Theorem, deeply rooted in fractal mathematics, presents a pioneering perspective on deciphering complex systems. It draws a profound connection between the principles of interchangeability, self-similarity, and the mathematical elegance of the Golden Ratio. This research unravels a unique methodological paradigm, emphasizing the omnipresence of the Golden Ratio in shaping system dynamics. The novelty of this study stems from its detailed exposition of self-similarity and interchangeability, transforming them from mere abstract notions into actionable, concrete insights. By highlighting the fractal nature of the Golden Ratio, the implications of these revelations become far-reaching, heralding new avenues for both theoretical advancements and pragmatic applications across a spectrum of scientific disciplines. 展开更多
关键词 Conservation Law self-similarity INTERCHANGEABILITY Golden Ratio Complex Systems Dynamic Exchange Structural Stability Mathematical Modeling Theoretical Framework P vs NP Millennium Problem
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An Intrusion Alarming System Based on Self-Similarity of Network Traffic 被引量:4
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作者 YUFei ZHUMiao-liang +2 位作者 CHENYu-feng LIRen-fa XUCheng 《Wuhan University Journal of Natural Sciences》 CAS 2005年第1期169-173,共5页
Intrusion detection system ean make effective alarm for illegality of networkusers, which is absolutely necessarily and important to build security environment of communicationbase service According to the principle t... Intrusion detection system ean make effective alarm for illegality of networkusers, which is absolutely necessarily and important to build security environment of communicationbase service According to the principle that the number of network traffic can affect the degree ofself-similar traffic, the paper investigates the variety of self-similarity resulted fromunconventional network traffic. A network traffic model based on normal behaviors of user isproposed and the Hursl parameter of this model can be calculated. By comparing the Hurst parameterof normal traffic and the self-similar parameter, we ean judge whether the network is normal or notand alarm in time. 展开更多
关键词 intrusion detection self-similarity network traffic model: networkprocessor
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On the Self-Similarity in Biological Processes 被引量:1
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作者 Oliver Szasz Gyula Peter Szigeti Andras Szasz 《Open Journal of Biophysics》 2017年第4期183-196,共14页
We show that the processes described by Avrami functions are self-similar. A comparative function characterizes a self-similar process by a certain Avrami exponent. We define the self-similar categories of some well-k... We show that the processes described by Avrami functions are self-similar. A comparative function characterizes a self-similar process by a certain Avrami exponent. We define the self-similar categories of some well-known biological processes. The method to determine the Avrami exponent by choosing the comparative function is demonstrated on the diffusion model of the growth of nuclei. We generalize the results. 展开更多
关键词 self-similar Process COMPARATIVE FUNCTION AVRAMI EXPONENT
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Measurement of Characteristic Self-Similarity and Self-Diversity for Complex Mechanical Systems
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作者 ZHOU Meili~1 LAI Jiangfeng~2 Hefei University of Technology,Hefei 230009,China 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S3期872-875,共4页
Based on similarity science and complex system theory,a new concept of characteristic self-diversity and corre- sponding relations between self-similarity and self-diversity for complex mechanical systems are presente... Based on similarity science and complex system theory,a new concept of characteristic self-diversity and corre- sponding relations between self-similarity and self-diversity for complex mechanical systems are presented in this paper.Methods of system self-similarity and self-diversity measure between main system and sub-system are studied.Numerical calculations show that the characteristic self-similarity and self-diversity measure method is validity.A new theory and method of self-similarity and self- diversity measure for complexity mechanical system is presented. 展开更多
关键词 COMPLEX mechanical system self-similarity MEASURE self-diversity MEASURE
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A MODEL OF RANDOM PARTICLES CONSTRUCTED BY THE PRINCIPLE OF SELF-SIMILARITY AND ITS APPLICATION
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作者 程登辉 王一平 《Journal of Electronics(China)》 1993年第1期56-62,共7页
A model of random particles constructed by the operation of self-similarity in fractalgeometry is presented.The correlation function of the number density has been obtained andcan be used conveniently in theoretical s... A model of random particles constructed by the operation of self-similarity in fractalgeometry is presented.The correlation function of the number density has been obtained andcan be used conveniently in theoretical study and computer simulation for wave interaction withrandom media.As an example,this model has been applied to calculate analytically the rangedependence of volume scattering in radar echoes.The result agrees with that of Rastogi andScheucher’s simulation. 展开更多
关键词 FRACTAL GEOMETRY self-similarity Correlation function
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Self-similarity of spanwise rotational motions’population trends in decelerating open-channel flow
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作者 Peng Zhang Yanchong Duan +4 位作者 Qiang Zhong Danxun Li Shengfa Yang Jiang Hu Wenjie Li 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2022年第3期213-219,共7页
Decelerating open-channel flow is a type of flow that gradually moves forward with decreasing velocity and increasing water depth.Although all flow parameters change along the streamwise direction,previous studies hav... Decelerating open-channel flow is a type of flow that gradually moves forward with decreasing velocity and increasing water depth.Although all flow parameters change along the streamwise direction,previous studies have revealed that these parameters’vertical distributions at different sections can be universally described with a single profile when being nondimensionalised by appropriate scales.This study focuses on the population trends of spanwise rotational motions at various sections along the main flow direction by particle imaging velocimetry(PIV)measurement.The wall-normal population distributions of density,radius,swirling strength,and convection velocity of the prograde and retrograde motions show similar trends in uniform open-channel flows.The dimensionless representation is invariant along the main flow direction.This study’s results indicate the self-similar characteristic of population trends of spanwise rotational motions prevails in decelerating open-channel flow. 展开更多
关键词 self-similarity Population trends Spanwise rotational motions Decelerating open-channel flow Equilibrium flow
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An Enhanced Nonlocal Self-Similarity Technique for Fabric Defect Detection
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作者 Boheng Wang Li Ma Jielin Jiang 《Journal of Information Hiding and Privacy Protection》 2019年第3期135-142,共8页
Fabric defect detection has been an indispensable and important link in fabric production,many studies on the development of vision based automated inspection techniques have been reported.The main drawback of existin... Fabric defect detection has been an indispensable and important link in fabric production,many studies on the development of vision based automated inspection techniques have been reported.The main drawback of existing methods is that they can only inspect a particular type of fabric pattern in controlled environment.Recently,nonlocal self-similarity(NSS)based method is used for fabric defect detection.This method achieves good defect detection performance for small defects with uneven illumination,the disadvantage of NNS based method is poor for detecting linear defects.Based on this reason,we improve NSS based defect detection method by introducing a gray density function,namely an enhanced NSS(ENSS)based defect detection method.Meanwhile,mean filter is applied to smooth images and suppress noise.Experimental results prove the validity and feasibility of the proposed NLRA algorithm. 展开更多
关键词 Fabric defect detection nonlocal self-similarity mean filter
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Another Important Parameter’s Research on Estimating Self-Similarity
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作者 Peng Luo Juan Wang 《International Journal of Communications, Network and System Sciences》 2016年第8期338-345,共9页
It is convincingly demonstrated by numerous studies that the self-similarity of modern multimedia network traffic is presented by Hurst parameter (H). The specific performance is that the similar degree is higher alon... It is convincingly demonstrated by numerous studies that the self-similarity of modern multimedia network traffic is presented by Hurst parameter (H). The specific performance is that the similar degree is higher along with the increase of H when H is between 0.5 and 1. However, it is doubtable that whether the complicated process of self-similarity can be described comprehensively by the parameter H only. Therefore, another important parameter cf has been proposed based on the discrete wavelet decomposition in this paper. The significance of the parameters is provided and the performance of the self-similarity process is described better. 展开更多
关键词 self-similarity Hurst Parameter Parameter cf Long-Rang Dependence
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On Self-Similarity of Top Production at Tevatron
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作者 Mikhail Tokarev Imrich Zborovsky 《Journal of Modern Physics》 2012年第8期815-820,共6页
This paper presents the results of analysis of the D? 1.0 fb-1 data on top-quark differential cross section measurements at the Fermilab Tevatron collider at √s= 1960 GeV in the framework of z-scaling approach. The f... This paper presents the results of analysis of the D? 1.0 fb-1 data on top-quark differential cross section measurements at the Fermilab Tevatron collider at √s= 1960 GeV in the framework of z-scaling approach. The flavor independence of scaling function Ψ(z)observed in pp and pp interactions over a wide collision energy range √s= 19-1960 GeV has been verified. This property of Ψ(z) was found for different hadrons – from π-mesons up to Υ particles. The flavor independence of Ψ(z) is used as indication on self-similarity of the top-quark production. A tendency to saturation of Ψ(z) at low z for top-quark production has been confirmed. Momentum fraction x1 of the incoming (anti)protons as a function of the scaled transverse momentum pT/m and masses of heavy mesons is studied. We anticipate that the data on low- and high-pT inclusive spectra of the top-quark production at the Tevatron and LHC energies could be of interest to verify self-similarity over a wide range of masses and different flavor content of produced particles. 展开更多
关键词 Inelastic Cross Section Proton-AntiProton Collisions Top Production Scaling self-similarity
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Density-based ship detection in SAR images:Extension to a self-similarity perspective
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作者 Xueqian WANG Gang LI +2 位作者 Zhizhuo JIANG Yu LIU You HE 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第3期168-180,共13页
Nonlocal self-similarity is an important property of Synthetic Aperture Radar(SAR)images to characterize the repetitiveness of features embodied by SAR images within nonlocal areas and has been used for enhancement of... Nonlocal self-similarity is an important property of Synthetic Aperture Radar(SAR)images to characterize the repetitiveness of features embodied by SAR images within nonlocal areas and has been used for enhancement of SAR images.Existing SAR ship detectors often independently handle small sub-images cropped from a large marine SAR image and do not exploit the nonlocal self-similarity therein.In this paper,we propose a new ship detector from the perspective of nonlocal self-similarity in SAR images to improve the ship detection performance,basically including three stages:prescreening,intra-cue calculation,and inter-cue calculation.In the prescreening stage,we design a new Histogram-based Density(HD)feature to rapidly select candidate sub-images potentially containing ship targets from a large SAR image.In the intra-cue calculation stage,target cues within a single candidate sub-image are extracted.In the inter-cue calculation stage,thanks to the nonlocal self-similarity among different candidate sub-images in terms of density features,we innovatively extract a weighted superpixel-HD map to obtain accumulated intracues across all the candidate sub-images.Finally,for each candidate sub-image,we fuse its inter-cue and intra-cue to obtain final detection results.Experimental results based on real SAR images show that our newly proposed method provides a better target-to-clutter contrast and ship detection performance than those of other state-of-the-art detection approaches. 展开更多
关键词 Ship detection Synthetic aperture radar(SAR) DENSITY self-similarity HISTOGRAM
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A NEGATIVE ANSWER TO A CONJECTURE ON SELF-SIMILAR SETS WITH OPEN SET CONDITION 被引量:5
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作者 Jiandong Yin 《Analysis in Theory and Applications》 2009年第2期182-200,共19页
关键词 self-similar set best covering natural covering Hausdorff measure
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AN ANSWER TO A CONJECTURE ON SELF-SIMILAR SETS 被引量:4
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作者 Baoguo Jia Shaoyuan Xu 《Analysis in Theory and Applications》 2007年第1期9-15,共7页
关键词 self-similar set best covering natural covering Hausdorff measure
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Spatiotemporal self-similar solutions for the nonautonomous (3+1)-dimensional cubic-quintic Gross-Pitaevskii equation 被引量:2
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作者 戴朝卿 陈瑞品 王悦悦 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第3期145-150,共6页
With the help of similarity transformation, we obtain analytical spatiotemporal self-similar solutions of the nonautonomous (3+1)-dimensional cubic-quintic Gross-Pitaevskii equation with time-dependent diffraction,... With the help of similarity transformation, we obtain analytical spatiotemporal self-similar solutions of the nonautonomous (3+1)-dimensional cubic-quintic Gross-Pitaevskii equation with time-dependent diffraction, nonlinearity, harmonic potential and gain or loss when two constraints are satisfied. These constraints between the system parameters hint that self-similar solutions form and transmit stably without the distortion of shape based on the exact balance between the diffraction, nonlinearity and the gain/loss. Based on these analytical results, we investigate the dynamic behaviours in a periodic distributed amplification system. 展开更多
关键词 Gross-Pitaevskii equation similarity transformation self-similar solutions
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THE REGULARITY OF RANDOM GRAPH DIRECTED SELF-SIMILAR SETS 被引量:2
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作者 ZhangXiaoqun LiuYanyan 《Acta Mathematica Scientia》 SCIE CSCD 2004年第3期485-492,共8页
A set in Rd is called regular if its Hausdorff dimension coincides with its upper box counting dimension. It is proved that a random graph-directed self-similar set is regular a.e..
关键词 Random graph-directed self-similar set Hausdorff dimension box-counting dimension REGULAR
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MULTIRESOLUTION ANALYSIS, SELF-SIMILAR TILINGS AND HAAR WAVELETS ON THE HEISENBERG GROUP 被引量:2
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作者 刘和平 刘宇 王海辉 《Acta Mathematica Scientia》 SCIE CSCD 2009年第5期1251-1266,共16页
In this article, the properties of multiresolution analysis and self-similar tilings on the Heisenberg group are studied. Moreover, we establish a theory to construct an orthonormal Haar wavelet base in L^2(H^d) by ... In this article, the properties of multiresolution analysis and self-similar tilings on the Heisenberg group are studied. Moreover, we establish a theory to construct an orthonormal Haar wavelet base in L^2(H^d) by using self-similar tilings for the acceptable dilations on the Heisenberg group. 展开更多
关键词 Heisenberg group multiresolution analysis WAVELETS self-similar tilings
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SELF-SIMILAR SOLUTIONS AND BLOW-UP PHENOMENA FOR A TWO-COMPONENT SHALLOW WATER SYSTEM 被引量:2
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作者 周寿明 穆春来 王良晨 《Acta Mathematica Scientia》 SCIE CSCD 2013年第3期821-829,共9页
In this article, we consider a two-component nonlinear shallow water system, which includes the famous 2-component Camassa-Holm and Degasperis-Procesi equations as special cases. The local well-posedess for this equat... In this article, we consider a two-component nonlinear shallow water system, which includes the famous 2-component Camassa-Holm and Degasperis-Procesi equations as special cases. The local well-posedess for this equations is established. Some sufficient conditions for blow-up of the solutions in finite time are given. Moreover, by separation method, the self-similar solutions for the nonlinear shallow water equations are obtained, and which local or global behavior can be determined by the corresponding Emden equation. 展开更多
关键词 self-similar solutions blow-up phenomena two-component shallow water system
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ON THE SELF-SIMILAR SOLUTIONS OF THE MAGNETO-HYDRO-DYNAMIC EQUATIONS 被引量:2
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作者 何成 辛周平 《Acta Mathematica Scientia》 SCIE CSCD 2009年第3期583-598,共16页
In this paper, we show that, for the three dimensional incompressible magnetohydro-dynamic equations, there exists only trivial backward self-similar solution in L^p(R^3) for p ≥ 3, under some smallness assumption ... In this paper, we show that, for the three dimensional incompressible magnetohydro-dynamic equations, there exists only trivial backward self-similar solution in L^p(R^3) for p ≥ 3, under some smallness assumption on either the kinetic energy of the self-similar solution related to the velocity field, or the magnetic field. Second, we construct a class of global unique forward self-similar solutions to the three-dimensional MHD equations with small initial data in some sense, being homogeneous of degree -1 and belonging to some Besov space, or the Lorentz space or pseudo-measure space, as motivated by the work in [5]. 展开更多
关键词 magneto-hydro-dynamics equations backward self-similar solutions forwardself-similar solutions
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The Exact Measure Functions of the Images for a Class of Self-Similar Processes 被引量:2
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作者 HUANG Li-hu LI Bing-zhang LIU Lu-qin (College of Mathematics and Computer Science, Wuhan University, Wuhan 430072, China) 《Wuhan University Journal of Natural Sciences》 CAS 2000年第1期1-6,共6页
Let X= (Ω, ■, ■_t, X_t,, θ_t, p~x) be a self-similar Markov process on (0,∞) with non-decreasing path. The exact Hausdorff and Packing measure functions of the image X([0,t] ) are obtained.
关键词 self-similar Markov process exact Hausdorff measure functions exact Packing measure function
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