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Application of Fractal Technology in the Generative Design of Chaoshan Drawnwork Patterns
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作者 CHEN Jia-jun ZHANG Ya CHEN Zhao-yang 《印刷与数字媒体技术研究》 北大核心 2025年第5期179-194,共16页
Chaoshan drawnwork handkerchief design exhibits self-similarity and fractal characteristics due to their grid-based structure,overall symmetry,and the way local motifs reflect the whole pattern.To explore the potentia... Chaoshan drawnwork handkerchief design exhibits self-similarity and fractal characteristics due to their grid-based structure,overall symmetry,and the way local motifs reflect the whole pattern.To explore the potential of fractals in traditional textile design,a fractal-based generative framework was proposed for efficiently creating drawnwork patterns suitable for practical handicraft production.The research was initiated with an analysis of the structural composition of center,skeleton,and filler motifs extracted from a pattern sample library.Based on this hierarchical classification,the box-counting method was employed to calculate their respective fractal dimensions.Building on fractal art theory,generative algorithms,and studies on the application of Ultra Fractal,a Chaoshan drawnwork fractal design model was established.Using this model,51 drawnwork fractal patterns and 153 handkerchief patterns were generated.These patterns were subsequently applied in real-world production to validate the feasibility and value of fractal techniques in textile design. 展开更多
关键词 Chaoshan drawnwork fractal pattern Generative design Cultural heritage
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Shear fracture behavior and fracture fractal characteristics of granite under adverse effect of cyclic heating
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作者 JIANG Tian-qi CHEN Bing +5 位作者 ZHANG Qing-song SHEN Bao-tang BAI Ji-wen LIU Ren-tai CHEN Meng-jun SASAOKA Takashi 《Journal of Central South University》 2025年第9期3405-3426,共22页
Deep geothermal extraction processes expose rock masses to frequent and significant temperature fluctuations. Developing a comprehensive understanding of the shear fracture mechanisms and crack propagation behaviors i... Deep geothermal extraction processes expose rock masses to frequent and significant temperature fluctuations. Developing a comprehensive understanding of the shear fracture mechanisms and crack propagation behaviors in rocks under the influence of cyclic heating is imperative for optimizing geothermal energy extraction. This study encompasses several critical aspects under cyclic heating conditions, including the assessment of stress distribution states, the characterization of two-dimensional fracture paths, the quantitative analysis of three-dimensional damage characteristics on fracture surfaces, and the determination of the fractal dimension of debris generated after the failure of granite. The test results demonstrate that cyclic heating has a pronounced adverse effect on the physical and mechanical properties of granite. Consequently, stress tends to develop and propagate in a direction perpendicular to the two-dimensional fracture path. This leads to an increase in the extent of tensile damage on the fracture surface and accelerates the overall rock failure process. This increases the number of small-sized debris, raises the fractal dimension, and enhances the rock’s rupture degree. In practical enhanced geothermal energy extraction, the real-time monitoring of fracture propagation within the reservoir rock mass is achieved through the analysis of rock debris generated during the staged fracturing process. 展开更多
关键词 progressive thermal damage stress distribution characteristics two-dimensional fracture path three-dimensional fracture surface failure characteristics fractal dimension
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Designing of optimized microstrip fractal antenna using hybrid metaheuristic framework for IoT applications
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作者 S KARUNAKAR Reddy ANITHA Guttavelli 《Journal of Systems Engineering and Electronics》 2025年第3期659-670,共12页
Nowadays,wireless communication devices turn out to be transportable owing to the execution of the current technologies.The antenna is the most important component deployed for communication purposes.The antenna plays... Nowadays,wireless communication devices turn out to be transportable owing to the execution of the current technologies.The antenna is the most important component deployed for communication purposes.The antenna plays an imperative role in receiving and transmitting the signals for any sensor network.Among varied antennas,micro strip fractal antenna(MFA)significantly contributes to increasing antenna gain.This study employs a hybrid optimization method known as the elephant clan updated grey wolf algorithm to introduce an optimized MFA design.This method optimizes antenna characteristics,including directivity and gain.Here,the factors,including length,width,ground plane length,height,and feed offset-X and feed offset-Y,are taken into account to achieve the best performance of gain and directivity.Ultimately,the superiority of the suggested technique over state-of-the-art strategies is calculated for various metrics such as cost and gain.The adopted model converges to a minimal value of 0.2872.Further,the spider monkey optimization(SMO)model accomplishes the worst performance over all other existing models like elephant herding optimization(EHO),grey wolf optimization(GWO),lion algorithm(LA),support vector regressor(SVR),bacterial foraging-particle swarm optimization(BF-PSO)and shark smell optimization(SSO).Effective MFA design is obtained using the suggested strategy regarding various parameters. 展开更多
关键词 micro strip fractal antenna(MFA)model gain DIRECTIVITY support vector regressor(SVR)approach elephant clan updated grey wolf algorithm(ECU-GWA)
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非退化扩散过程样本轨道的Fractal性质 被引量:1
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作者 匡能晖 杨新建 《湖南师范大学自然科学学报》 EI CAS 北大核心 2003年第1期20-24,28,共6页
讨论了N维非退化扩散过程样本轨道的性质 ,并由此得到一维非退化扩散过程样本轨道的象集和逆象集的Hausdorff维数 .此外 ,研究了当N >4时 ,其样本轨道的二重点问题 .
关键词 非退化扩散过程 样本轨道 fractal性质 象集 逆象集 HAUSDORFF维数 二重点 随机过程
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Fractal Feature of Western Fracture Zone in Xikuangshan Antimony Mine and its Geological Significance 被引量:2
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作者 TANG Shi-jia GAO Guang-ming +1 位作者 PENG En-sheng SUN Zhen-jia 《Journal of Central South University》 SCIE EI CAS 2000年第4期212-215,共4页
In Xikuangshan antimony ore-field, the western fracture zone is a composite of major fault, F75, and its secondary faults, such as F71, F72 and F3 etc.. On plane, the fracture zone scatters from southwest to northeast... In Xikuangshan antimony ore-field, the western fracture zone is a composite of major fault, F75, and its secondary faults, such as F71, F72 and F3 etc.. On plane, the fracture zone scatters from southwest to northeast, and concentrates from upper to deeper level on profile. All ore-bodies exist in the carbonate of footwall of the major fault or that of the footwall of its secondary faults. From 480 m and 320 m to 120 m level, the fractal dimensional number of the fault system decreases from 1.482 2 and 1.448 6 to 1.339 2, which indicates the form of fracture zone becoming more simple at deeper level. And in five sub-ranges, the III and IV sub-ranges are the known area, and the I, II and V sub-ranges are unknown. The fractal studies of the western fracture zone in these sub-ranges show that the fractal dimensional numbers of the I and II, being 1.201 5 and 1.278 0, respectively, are smaller than that of the III and IV, being 1.475 9 and 1.576 9, respectively; and that of the V, being 1.571 2, keeps with that of the III, IV sub-ranges. So mineralization is not well in I and II sub-ranges, and V sub-range is the best to benefit mineralization. 展开更多
关键词 fractal fractal dimension fracture zone Xikuangshan antimony-mine
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Fractal集的容量密度和Hausdorff维数
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作者 文志英 章逸平 《数学物理学报(A辑)》 CSCD 北大核心 1992年第4期419-421,共3页
为研究Fractal集的局部结构,本文引入了容量密度,设ER^d为Hausdorff维数为s的解析集,本文证明了对任意O<t<s,E中使得t-容量(上)密度大于零的点所成的集合维数亦为S,由此可得到由容量密度来刻划的Hausdorff维数的一个等价定义。
关键词 容量密度 fractal 豪斯道夫维数
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STUDY ON MULTI-RANGE FRACTALS IN FRACTURED SURFACE OF ROCK
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作者 Zhitie Zhang Zheng Xia 《Journal of Central South University》 SCIE EI CAS 1999年第1期49-51,共3页
Some profile of a rock section and some isopleth of a fractured surface of the rock were divided each into three parts. Then three parts were measured by dividers method and lattice method. It was discovered that the... Some profile of a rock section and some isopleth of a fractured surface of the rock were divided each into three parts. Then three parts were measured by dividers method and lattice method. It was discovered that the fractal dimensions of the three parts were remarkably different, so the fractured surface of rock was not simple fractal but multi range fractals. 展开更多
关键词 fractal multi range fractals SURFACE of ROCK dividers METHOD LATTICE METHOD
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FRACTAL及其在计算机图形学中的应用
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作者 王小铭 《华南师范大学学报(自然科学版)》 CAS 1995年第3期114-121,共8页
本文介绍一种崭新的理论和方法─FRAcTAL,它的创立、理论基础和研究领域,给出了FRACTAL在计算机图形学中应用的几个方面,其中引用了若干国外新近发表的例子,文中提及FRACTAL应用于图形学的新设想,对进一步探... 本文介绍一种崭新的理论和方法─FRAcTAL,它的创立、理论基础和研究领域,给出了FRACTAL在计算机图形学中应用的几个方面,其中引用了若干国外新近发表的例子,文中提及FRACTAL应用于图形学的新设想,对进一步探索FRATCAL在计算机图形学中的应用有一定的指导意义. 展开更多
关键词 fractal 计算机图形学 图像压缩
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一类复值函数图象的fractal维数
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作者 刘华民 《应用数学》 CSCD 北大核心 1995年第4期446-452,共7页
本文讨论一类连续而无处可微的复值函数,给出其图象的box维数与packing维数的表达式。
关键词 复值函数 函数图象 fractal维数 PACKING维数
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Electromagnetic Scattering from Fractal Multilayered Cylinde rat  Normal Incidence
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作者 Wu Zhensen & Guo LixinXidian ( University, Xi’an 710071 , P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1997年第1期1-6,共6页
this paper, a more stable and accurate recursing equation and computing procedure are proposed to calculate scattering width of the multilayered cylinder. This procedure is applied to compute the distribution of the s... this paper, a more stable and accurate recursing equation and computing procedure are proposed to calculate scattering width of the multilayered cylinder. This procedure is applied to compute the distribution of the scattering width and to analyze the characteristic of scattering from fractal multilayered cylinder. The connection between the characteristic of scattering and fractal dimension is discussed, and some important results are obtained. 展开更多
关键词 Electromagnetic scattering fractal fractal dimension Numerical recursion.
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Fractal图形学 被引量:2
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作者 董士海 张晖 《计算机辅助设计与图形学学报》 EI CSCD 1990年第1期69-73,共5页
Fractal图形学是计算机图形学中近年来产生并发展得十分迅速的一个领域,它在复杂自然景象的图形生成方面已经取得明显的效果。本文概述了Fractal图形学的研究对象及其数学基础——Fractal几何学,并着重介绍了Fractal图形学中构造模型的... Fractal图形学是计算机图形学中近年来产生并发展得十分迅速的一个领域,它在复杂自然景象的图形生成方面已经取得明显的效果。本文概述了Fractal图形学的研究对象及其数学基础——Fractal几何学,并着重介绍了Fractal图形学中构造模型的主要目标和几个方法:随机插值模型、粒子系统模型、正规文法模型和迭代函数系统模型。 展开更多
关键词 计算机图形学 fractal
全文增补中
一类有规Fractal曲线及其Fractal Dimension
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作者 黄雪梅 《云南民族学院学报(哲学社会科学版)》 CSSCI 北大核心 1993年第1期50-53,共4页
关键词 自相似集 相似维数 fractal曲线 fractal维数
全文增补中
一种基于Fractal-DenseNet的电磁血管断层图像重建算法
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作者 杨丹 王雨佳 +1 位作者 辛采凝 徐彬 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2023年第7期931-937,共7页
针对电磁血管断层图像重建中存在的欠定性、病态性,提出一种基于Fractal-DenseNet的电磁血管断层图像重建算法.基于血流磁电耦合效应的血管断层图像重建原理,将FractalNet的分形思想与DenseNet的密集紧密连接思想相结合,构建了一种适用... 针对电磁血管断层图像重建中存在的欠定性、病态性,提出一种基于Fractal-DenseNet的电磁血管断层图像重建算法.基于血流磁电耦合效应的血管断层图像重建原理,将FractalNet的分形思想与DenseNet的密集紧密连接思想相结合,构建了一种适用于反演血液流速分布的Fractal-DenseNet网络模型,用于血管断层图像重建.通过人体前臂尺动脉血流磁电耦合测量模型,建立血管断层剖面流速和血流磁电效应引起的电压信号的对应数据对,分别作为网络模型输入和输出;通过监督学习,实现基于血管断层流速分布的血管断层图像重建.结果表明:Fractal-DenseNet重建结果的均方根误差和相关系数分别为0.0078,99.28%;本文算法具有良好的抗噪性,可在复杂边界条件下实现血管断层图像重建. 展开更多
关键词 血管断层图像重建 fractal-DenseNet 血流磁电耦合效应 人体前臂尺动脉 监督学习
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广义Moran集的重Fractal分解 被引量:3
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作者 苏峰 《数学年刊(A辑)》 CSCD 北大核心 1994年第2期134-144,共11页
设K为广义Moran集.μ为支撑在K上的无穷乘积测度,本文研究结合μ的K的重fractal分解,利用配齐降阶技巧与网测度技巧讨论了在此分解下维谱f(α)的性质,并讨论了若干很重要的典型例子.
关键词 广义Moran集 fractal分解 维谱
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Fractal几何的理论形成及应用发展 被引量:9
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作者 叶万辉 马克明 陈华豪 《东北林业大学学报》 CAS CSCD 北大核心 1993年第6期84-88,共5页
在阐述Fractal几何由来和应用发展的基础上,分析了它在应用过程中对其理论体系的完善过程。着重指出目前Fractal几何理论不再局限于对自然形体的形态描述及形成过程的分析上,而已开始用于对抽象表现空间的自然现象及关系的评价。Fracta... 在阐述Fractal几何由来和应用发展的基础上,分析了它在应用过程中对其理论体系的完善过程。着重指出目前Fractal几何理论不再局限于对自然形体的形态描述及形成过程的分析上,而已开始用于对抽象表现空间的自然现象及关系的评价。Fractal一词也在理论和应用发展过程中扩展了内涵。这充分说明理论和实践相辅相承共同发展这一哲学观点的正确性。 展开更多
关键词 分数维几何 自相似性 尺度
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Calculating changes in fractal dimension of surface cracks to quantify how the dynamic loading rate affects rock failure in deep mining 被引量:31
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作者 GAO Ming-zhong ZHANG Jian-guo +3 位作者 LI Sheng-wei WANG Man WANG Ying-wei CUI Peng-fei 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第10期3013-3024,共12页
The split-Hopkinson pressure bar(SHPB)and digital image correlation(DIC)techniques are combined to analyze the dynamic compressive failure process of coal samples,and the box fractal dimension is used to quantitativel... The split-Hopkinson pressure bar(SHPB)and digital image correlation(DIC)techniques are combined to analyze the dynamic compressive failure process of coal samples,and the box fractal dimension is used to quantitatively analyze the dynamic changes in the coal sample cracks under impact load conditions with different loading rates.The experimental results show that the fractal dimension can quantitatively describe the evolution process of coal fractures under dynamic load.During the dynamic compression process,the evolution of the coal sample cracks presents distinct stages.In the crack propagation stage,the fractal dimension increases rapidly with the progress of loading,and in the crack widening stage,the fractal dimension increases slowly with the progress of loading.The initiation of the crack propagation phase of the coal samples gradually occurs more quickly with increasing loading rate;the initial cracks appear earlier.At the same loading time point,when the loading rate is greater,the fractal dimension of the cracks observed in the coal sample is greater. 展开更多
关键词 fractal dimension loading rate impact load coal crack
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Grouting diffusion of chemical fluid flow in soil with fractal characteristics 被引量:6
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作者 ZHOU Zi-long DU Xue-ming +1 位作者 CHEN Zhao ZHAO Yun-long 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第5期1190-1196,共7页
The chemical fluid property and the capillary structure of soil are important factors that affect grouting diffusion. Ignoring either factor will produce large errors in understanding the inherent laws of the diffusio... The chemical fluid property and the capillary structure of soil are important factors that affect grouting diffusion. Ignoring either factor will produce large errors in understanding the inherent laws of the diffusion process. Based on fractal geometry and the constitutive equation of Herschel-Bulkley fluid, an analytical model for Herschel-Bulkley fluid flowing in a porous geo-material with fractal characteristics is derived. The proposed model provides a theoretical basis for grouting design and helps to understand the chemical fluid flow in soil in real environments. The results indicate that the predictions from the proposed model show good consistency with the literature data and application results. Grouting pressure decreases with increasing diffusion distance. Under the condition that the chemical fluid flows the same distance, the grouting pressure undergoes almost no change at first and then decreases nonlinearly with increasing tortuosity dimension. With increasing rheological index, the pressure difference first decreases linearly, then presents a trend of nonlinear decrease, and then decreases linearly again. The pressure difference gradually increases with increasing viscosity and yield stress of the chemical fluid. The decreasing trend of the grouting pressure difference is non-linear and rapid for porosity Φ>0.4, while there is a linear and slow decrease in pressure difference for high porosity. 展开更多
关键词 GROUTING DIFFUSION Herschel-Bulkley fluid POROUS MEDIA fractal GROUTING pressure
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Filtering of long-term dependent fractal noise in fiber optic gyroscope 被引量:5
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作者 Chunhong Hua Zhang Ren Minhu Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期1041-1045,共5页
Stochastic noises of fiber optic gyroscope (FOG) mainly contain white noise and fractal noise whose long-term dependent component causes FOG a rather slow drift. In order to eliminate this component, a two-step filt... Stochastic noises of fiber optic gyroscope (FOG) mainly contain white noise and fractal noise whose long-term dependent component causes FOG a rather slow drift. In order to eliminate this component, a two-step filtering methodology is proposed. Firstly, fractional differencing (FD) method is introduced to trans-form fractal noise into fractional white noise based on the estima-tion of Hurst exponent for long-term dependent fractal process, which together with the existing white noise make up of a gener-alized white noise. Further, an improved denoising algorithm of wavelet maxima is developed to suppress the generalized white noise. Experimental results show that the basic noise terms of FOG greatly decrease, and especially the slow drift is restrained effectively. The proposed methodology provides a promising ap-proach for filtering long-term dependent fractal noise. 展开更多
关键词 fiber optic gyroscope (FOG) fractal noise long-term dependence fractional differencing wavelet denoising.
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Existence detection of blanket jamming based on fractal characteristics in FRFT domain 被引量:5
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作者 Zhu Hong Jiang Ge +2 位作者 Zhang Hai Tang Gaodi Li Zhongyun 《强激光与粒子束》 EI CAS CSCD 北大核心 2016年第5期78-84,共7页
This paper addresses the existence detection of blanket jamming based on fractal features in fractional Fourier transform (FRET) domain. Firstly, the existences of fractal features of three typical jamming signals are... This paper addresses the existence detection of blanket jamming based on fractal features in fractional Fourier transform (FRET) domain. Firstly, the existences of fractal features of three typical jamming signals are analyzed, and box dimension and information dimension are employed to describe fractal features quantitatively. Then the differences of fractal characteristics between blanket jamming and white Gaussian noise (WGN) in FRFT domain are described, and a detector to detect the jamming is proposed. At last, simulations are done to verify that the algorithm is effective preferable. 展开更多
关键词 BLANKET jamming fractal FRACTIONAL FOURIER transform EXISTENCE DETECTION
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分形维数(Fractal dimension)及其测量方法 被引量:46
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作者 孙博玲 《东北林业大学学报》 CAS CSCD 北大核心 2004年第3期116-119,共4页
给出了相似维数、容量维数、盒子维数、信息维数、关联维数、广义维数分形维数等 6种分形维数的定义方式 ,并讨论了它们的应用范围。在此基础上 ,概括出改变粗视化程度求维数、根据测度关系求维数、根据关联函数求维数、根据分布函数求... 给出了相似维数、容量维数、盒子维数、信息维数、关联维数、广义维数分形维数等 6种分形维数的定义方式 ,并讨论了它们的应用范围。在此基础上 ,概括出改变粗视化程度求维数、根据测度关系求维数、根据关联函数求维数、根据分布函数求维数、根据波谱求维数等 5种测量维数的方法 ,为不同领域的科研人员应用维数测量提供了有力工具。 展开更多
关键词 分形维数 粗视化 无标度区
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