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Optimization of Fractal Iterated Function System(IFS) with Probability and Fractal Image Generation 被引量:6
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作者 Berthe Kya, Yang Yang (Information Engineering School, University of Science and Technology Beijing, Beijing 100083, China) 《Journal of University of Science and Technology Beijing》 CSCD 2001年第2期152-156,共5页
There are several methods for rendering fractal images based on IFS (Iterated Function System) in computer graphic; but one concern of the computer graphic community has been the efficiency rendering algorithms. The i... There are several methods for rendering fractal images based on IFS (Iterated Function System) in computer graphic; but one concern of the computer graphic community has been the efficiency rendering algorithms. The invariant measures arising from IFSP (Iterate Function System with Probability) using the probabilistic algorithm are also known as chaos games. The role of these probabilities to generate the image of the attractor has been investigated using a multi-fractal analysis. The conventional choice of probability associated with each set /S/ to generate the attractor in least time possible is introduced, then a new method based on the self similarity and multi-fractal analysis is presented. The efficiency of the new method has been proved over the conventional method. 展开更多
关键词 optimization of fractal ifs compression ifsP multi-fractal analysis
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A HIGH SPEED ADAPTIVE FRACTAL IMAGE CODING ALGORITHM USING FLEXIBLE CLASSIFICATION TECHNIQUE
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作者 Zhang Liang Li Weihua Wang Qiao 《Wuhan University Journal of Natural Sciences》 CAS 1998年第2期146-146,共1页
Traditionally, fractal image compression suffers from lengthy encoding time in measure ofhours. In this paper, combined with characteristlcs of human visual system, a flexible classification technique is proposed. Thi... Traditionally, fractal image compression suffers from lengthy encoding time in measure ofhours. In this paper, combined with characteristlcs of human visual system, a flexible classification technique is proposed. This yields a corresponding adaptive algorithm which can cut down the encoding timeinto second's magnitude. Experiment results suggest that the algorithm can balance the overall encodingperformance efficiently, that is, with a higher speed and a better PSNR gain. 展开更多
关键词 image coding fractal image coding iterated function system (ifs) partitioned iterated function system (Pifs) characteristics of human visual system
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Real-Time Tool for Affine Transformations of Two Dimensional IFS Fractal
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作者 Elena Hadzieva Marija Shuminoska 《Journal of Electrical Engineering》 2016年第3期150-155,共6页
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Realization of Fractal Affine Transformation 被引量:1
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作者 XU Jing, LIN Yi xia School of Electromechanical Engineering and Automation, Shanghai University, Shanghai 200072, China 《Journal of Shanghai University(English Edition)》 CAS 2001年第1期31-34,共4页
This paper gives the definition of fractal affine transformation and presents a specific method for its realization and its corresponding mathematical equations which are essential in fractal image construction.
关键词 fractal ifs (iterated function system) affine transformation
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ON SPACES OF FRACTAL FUNCTIONS 被引量:1
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作者 Qian Xiaoyuan(Dalian University of Technology,China) 《Analysis in Theory and Applications》 1996年第1期42-52,共11页
In this paper we Ointroduce linear-spaces consisting of continuous functions whose graphs are the attactars of a special class of iterated function systems. We show that such spaces are finite dimensional and give the... In this paper we Ointroduce linear-spaces consisting of continuous functions whose graphs are the attactars of a special class of iterated function systems. We show that such spaces are finite dimensional and give the bases of these spaces in an implicit way. Given such a space, we discuss how to obtain a set of knots for whah the Lagrange interpolation problem by the space is uniquely solvable. 展开更多
关键词 IGS ON SPACES OF fractal FUNCTIONS ifs
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DETECTION OF KNOWN SIGNALS IN 1/f FRACTAL NOISE
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作者 Xie Wenlu Zhang Qianling(ASIC and Systems State Key Lab, Fudan University, Shanghai 200433)Chen Yanhui Xie Weixin(Department of Electronic Engineering, Xidian University, Xi’an 710071) 《Journal of Electronics(China)》 1999年第2期152-158,共7页
Based on the whitening property of wavelet transformation for 1/f noise, this paper addresses the problem of detecting deterministic signals in the presence of 1/f fractal noise. The transfer function of whitening fil... Based on the whitening property of wavelet transformation for 1/f noise, this paper addresses the problem of detecting deterministic signals in the presence of 1/f fractal noise. The transfer function of whitening filter is provided as well as the condition for whitening. The receiver structure based on Karhunen-Loeve expansion and the decision rule are also given. Finally performance of the detector is analyzed. 展开更多
关键词 SIGNAl DETECTION fractal WAVElET analysis l/f-type SIGNAl
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Multi-fractal Behaviors of Relative Humidity over China 被引量:2
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作者 GAO Li-Hao FU Zun-Tao 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第2期74-78,共5页
The multi-fractal behaviors of relative humidity over China are studied using the multi-fractal detrended fluctuation analysis (DFA) method. Three multi-fractal parameters (the spectrum width Δα, the asymmetry Δα ... The multi-fractal behaviors of relative humidity over China are studied using the multi-fractal detrended fluctuation analysis (DFA) method. Three multi-fractal parameters (the spectrum width Δα, the asymmetry Δα as , and the long-range correlation exponent α 0 ) of the singularity spectrum are introduced to quantify the multi-fractal behaviors. The results show that multi-fractality exists in daily humidity records over most stations in China and is mainly due to the broad distribution of the probability density of the sequence values. Strong multifractal behaviors over some stations in the Yunnan, Guangdong, and Inner Mongolia provinces are obvious. These behaviors are mainly caused by different longrange correlations between large and small fluctuations. The asymmetry of the singularity of relative humidity records is weak, except for a small number of stations in the far east and west of China, where the singularity spectrum is left-skewed. Finally, the long-range correlations in North China are stronger than those in South China, which indicates better predictability in North China. By studying the parameters of the multi-fractal spectrum, various data of long-range power law correlations of the relative humidity records are obtained, which may provide theoretical support for climate prediction. 展开更多
关键词 中国西部地区 分形行为 相对湿度 多重分形 概率密度分布 波动分析 气候预测 频谱宽度
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Simulation of tree and its swaying with wind generated by L-system 被引量:1
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作者 Liu Ziping Xia Qixiao Yu Yue 《Computer Aided Drafting,Design and Manufacturing》 2017年第1期15-21,共7页
This paper constructs a tree model by using the 3D stochastic and L system with brackets. Adjusting the range of the parameters, the present method ensures a favorable randomness and reflects the reality and the real ... This paper constructs a tree model by using the 3D stochastic and L system with brackets. Adjusting the range of the parameters, the present method ensures a favorable randomness and reflects the reality and the real time. Based on a simple mechanical model, the simulation of the phenomenon of wind swaying trees satisfies visual effects well. 展开更多
关键词 SIMUlATION tree flapping l-system fractal geometry
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Fractal-based algorithmic design of Chinese ice-ray lattices 被引量:1
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作者 lasef Md Rian 《Frontiers of Architectural Research》 CSCD 2022年第2期324-339,共16页
Chinese ice-ray lattices are perhaps one of the earliest and controlled designs of asymmetric and complex patterns applied as a traditional motif in windows.Such intricate and complex designs developed centuries back ... Chinese ice-ray lattices are perhaps one of the earliest and controlled designs of asymmetric and complex patterns applied as a traditional motif in windows.Such intricate and complex designs developed centuries back have created an evident curiosity to explore its underlying geometric rules.Some scholars used the Shape Grammar as a tool to explain and recreate similar patterns.The previous studies conceive the ice-ray lattice design as the iterative subdivisions of a polygon.However,they missed explaining this geometric quality through the discussion of fractal geometry,which can explain the shapes consuming selfsimilar or self-affine repetitions of itself at different scales.As a novel approach,this paper analytically focuses on the fractal characters of ice-ray lattice designs and uses fractal geometry as a unique tool for generating different types of ice-ray lattices.The significance of this study is the demonstration of the efficacy of fractal geometry and the simple geometric rule of IFS for analyzing and algorithmically modeling complex lattices and cracked-like patterns. 展开更多
关键词 Ice-ray Algorithm Random fractals ifs Visual complexity fractal dimension
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Weighing Leaves based on Physical Measurements and L-system Simulation
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作者 Xinyuan Gu 《International Journal of Technology Management》 2015年第4期113-115,共3页
关键词 物理测量 l系统 称重 模拟 蒙特卡洛方法 植物造型 分支结构 数学模型
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一种L系统与IFS相互融合的植物模拟方法 被引量:23
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作者 李庆忠 韩金姝 《工程图学学报》 CSCD 北大核心 2005年第6期135-139,共5页
提出了一种L系统与IFS相互融合的植物形态模拟新方法。利用L系统进行植物生长规律和拓扑结构的控制和模拟,由IFS方法模拟植物具有纹理的各组成部分,由此将两种方法的优点结合在一起。此外,为便于该融合方法的具体实现,还对传统L系统的... 提出了一种L系统与IFS相互融合的植物形态模拟新方法。利用L系统进行植物生长规律和拓扑结构的控制和模拟,由IFS方法模拟植物具有纹理的各组成部分,由此将两种方法的优点结合在一起。此外,为便于该融合方法的具体实现,还对传统L系统的实现算法进行了改进。模拟实验结果表明:提出的方法可以方便、自由地模拟各种植物的形态,且具有更加自然与逼真的效果。 展开更多
关键词 计算机应用 植物模拟 分形 l系统 迭代函数系统
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USING NEURAL NETWORK BASED NONLINEAR IFS TO MODEL TIME SEQUENCES
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作者 Yang Su Li Zhishun(institute of Marine Engineering, Northwestern Polytechnical University, Xi’an 710072) 《Journal of Electronics(China)》 1999年第4期367-371,共5页
A novel neural network based iterated function system (IFS) model is presented in this paper while the precondition to ensure the model is also explored. Applying it to some practical data, the given signal can be app... A novel neural network based iterated function system (IFS) model is presented in this paper while the precondition to ensure the model is also explored. Applying it to some practical data, the given signal can be approximated exactly by the attractor generated by this model, which provides another way to resolve fractal inverse problem. 展开更多
关键词 fractal fractal INVERSE problem ifs NEURAl network NONlINEAR
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Dynamic Fractal Transform with Applications to Image Data Compression
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作者 王舟 余英林 《Journal of Computer Science & Technology》 SCIE EI CSCD 1997年第3期202-209,共8页
A recent trend in computer graphics and image processing is to use Iterated Function System (IFS) to generate and describe both man-made graphics and natural images. Jacquin was the first to propose a fully automatic ... A recent trend in computer graphics and image processing is to use Iterated Function System (IFS) to generate and describe both man-made graphics and natural images. Jacquin was the first to propose a fully automatic gray scale image compression algorithm which is referred to as a typical static fractal transform based algorithm in this paper. By using this algorithm, an image can be condensely described as a fractal transform operator which is the combination of a set of fractal mappings. When the fractal transform operator is iteratedly applied to any initial image, a unique attractor (reconstructed image) can be achieved. In this paper) a dynamic fractal transform is presented which is a modification of the static transform. Instead of being fixed, the dynamic transform operator varies in each decoder iteration, thus differs from static transform operators. The new transform has advantages in improving coding efficiency and shows better convergence for the decoder. 展开更多
关键词 fractals Iterated Function system (ifs) data compression image processing
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Classification of cultivated Chinese medicinal plants based on fractal theory and gray level co-occurrence matrix textures 被引量:5
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作者 ZHENG Shudan ZHENG Jianghua +5 位作者 SHI Minghui GUO Baolin SEN Bati SUN Zhiqun JIA Xiaoguang LI Xiaojin 《遥感学报》 EI CSCD 北大核心 2014年第4期868-886,共19页
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分区IFS图像压缩编码 被引量:11
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作者 秦烽 吴征 +1 位作者 周峰 姚庆栋 《通信学报》 EI CSCD 北大核心 1997年第5期1-7,共7页
本文提出了一种基于“区”的IFS图像压缩编码算法,简述了其原理及实现过程。实验结果表明,其性能优于JPEG算法及Jacquin的基于“块”
关键词 分形 图像编码 ifs
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一种基于IFS的图像边缘检测方法 被引量:6
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作者 曹汉强 朱光喜 +1 位作者 朱耀庭 薛东辉 《信号处理》 CSCD 1997年第4期330-334,共5页
首次提出了一种基于IFS的图像边缘检测方法,该方法以IFS理论为基础、以MSE为失真测度,对图像进行边缘检测,改进的局部快速算法可以有效减少检测搜索时间。实验结果表明,本文所采用的边缘检测方法是一种有效的图像边缘检测方法。
关键词 分形压缩 图像边缘检测 图像编码 ifs 图像处理
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一种基于IFS的二维真彩分形变形方法 被引量:5
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作者 张莹 蒋大为 +1 位作者 危才华 张正贤 《计算机工程与应用》 CSCD 北大核心 2006年第10期84-86,195,共4页
提出了一种由迭代函数系统(IFS)所描述的二维真彩分形变形的新方法。首先建立二维真彩IFS分形模型,然后通过仿射变换的对应、规范化、匹配及插值实现了变形过程。实验结果表明:分形吸引子形状颜色过渡自然,这为分形的生成与动画提供了... 提出了一种由迭代函数系统(IFS)所描述的二维真彩分形变形的新方法。首先建立二维真彩IFS分形模型,然后通过仿射变换的对应、规范化、匹配及插值实现了变形过程。实验结果表明:分形吸引子形状颜色过渡自然,这为分形的生成与动画提供了新的有效途径。 展开更多
关键词 分形 迭代函数系统 变形 真彩 极值分解
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基于IFS的非规则分形组织设计方法 被引量:8
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作者 张聿 金耀 岑科军 《纺织学报》 EI CAS CSCD 北大核心 2012年第12期30-34,共5页
针对L系统在绘制织物分形组织图方面存在的局限,基于IFS的生成规则,研究不受任何基本组织形式限制的非规则分形组织设计方法。该方法以非规则、大循环的基本组织为应用对象,运用VC++编程,利用Kronecker叉积进行组织矩阵的迭代运算,快捷... 针对L系统在绘制织物分形组织图方面存在的局限,基于IFS的生成规则,研究不受任何基本组织形式限制的非规则分形组织设计方法。该方法以非规则、大循环的基本组织为应用对象,运用VC++编程,利用Kronecker叉积进行组织矩阵的迭代运算,快捷地生成此类基本组织的分形组织图。在此基础上,利用分形组织自相似结构所具有的多级层次关系,通过选择不同的填充组织,设计形成结构复杂、风格多变的分形织物。通过织造实验证明,此分形组织设计方法形成的织物纹理效果具有复杂性强,不易模仿等特点。 展开更多
关键词 ifs Kronecker叉积 非规则分形组织 织物 组织设计
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局部放电超声信号的自仿射IFS模型 被引量:3
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作者 刘云鹏 律方成 +2 位作者 陈志业 李燕青 刘孝义 《高电压技术》 EI CAS CSCD 北大核心 2002年第10期23-25,共3页
通过仿射变换建立了变压器局部放电超声信号的分段自仿射 IFS模型。该模型用于在线监测中可实现局部放电信号数据的压缩 ,并通过计算 IFS分形维数为局部放电模式识别提供新的特征参数。
关键词 局部放电 超声信号 自仿射ifs模型 变压器 分形理论
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基于L系统的织物分形组织设计方法 被引量:22
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作者 张聿 金耀 +2 位作者 孙家武 唐继杰 帅沁芬 《纺织学报》 EI CAS CSCD 北大核心 2007年第5期51-54,共4页
为探索一条与传统方法不同的织物组织设计新途径,基于L系统理论,以4枚破斜纹、5枚缎纹等组织为例,尝试提出一种新的织物组织设计方法。该方法运用L系统的链式语言生成规则与计算机图形技术,生成具有自相似性特征与相互嵌套、多层次结构... 为探索一条与传统方法不同的织物组织设计新途径,基于L系统理论,以4枚破斜纹、5枚缎纹等组织为例,尝试提出一种新的织物组织设计方法。该方法运用L系统的链式语言生成规则与计算机图形技术,生成具有自相似性特征与相互嵌套、多层次结构的分形组织,并通过选择合适的填充组织,构造出实用且与传统形式不同的织物分形组织。在此基础上,借助电子提花机进行了织物成型实验,由此对分形织物组织所产生的织物效果进行了初步的探讨。 展开更多
关键词 l系统 链式语言 计算机图形方法 分形组织 织物
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