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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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Fractals and Spatial Statistics of Point Patterns 被引量:5
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作者 Frederik P Agterberg 《Journal of Earth Science》 SCIE CAS CSCD 2013年第1期1-11,共11页
The relationship between fractal point pattern modeling and statistical methods of pa- rameter estimation in point-process modeling is reviewed. Statistical estimation of the cluster fractal dimension by using Ripley... The relationship between fractal point pattern modeling and statistical methods of pa- rameter estimation in point-process modeling is reviewed. Statistical estimation of the cluster fractal dimension by using Ripley's K-function has advantages in comparison with the more commonly used methods of box-counting and cluster fractal dimension estimation because it corrects for edge effects, not only for rectangular study areas but also for study areas with curved boundaries determined by re- gional geology. Application of box-counting to estimate the fractal dimension of point patterns has the disadvantage that, in general, it is subject to relatively strong "roll-off" effects for smaller boxes. Point patterns used for example in this paper are mainly for gold deposits in the Abitibi volcanic belt on the Canadian Shield. Additionally, it is proposed that, worldwide, the local point patterns of podiform Cr, volcanogenic massive sulphide and porphyry copper deposits, which are spatially distributed within irregularly shaped favorable tracts, satisfy the fractal clustering model with similar fractal dimensions. The problem of deposit size (metal tonnage) is also considered. Several examples are provided of cases in which the Pareto distribution provides good results for the largest deposits in metal size-frequency distribution modeling. 展开更多
关键词 fractal point pattern spatial statistics roll-off effect cluster dimension Pareto distribution.
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Improving the efficiency of magnetic coupling energy transfer byetching fractal patterns in the shielding metals 被引量:2
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作者 Qing-feng LI Shao-bo CHE +2 位作者 Wei-ming WANG Hong-wei HAO Lu-ming LI 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2016年第1期74-82,共9页
Thin metal sheets are often located in the coupling paths of magnetic coupling energy transfer(MCET) systems. Eddy currents in the metals reduce the energy transfer efficiency and can even present safety risks. This p... Thin metal sheets are often located in the coupling paths of magnetic coupling energy transfer(MCET) systems. Eddy currents in the metals reduce the energy transfer efficiency and can even present safety risks. This paper describes the use of etched fractal patterns in the metals to suppress the eddy currents and improve the efficiency. Simulation and experimental results show that this approach is very effective. The fractal patterns should satisfy three features, namely, breaking the metal edge, etching in the high-intensity magnetic field region, and etching through the metal in the thickness direction. Different fractal patterns lead to different results. By altering the eddy current distribution, the fractal pattern slots reduce the eddy current losses when the metals show resistance effects and suppress the induced magnetic field in the metals when the metals show inductance effects. Fractal pattern slots in multilayer high conductivity metals(e.g., Cu) reduce the induced magnetic field intensity significantly. Furthermore, transfer power, transfer efficiency, receiving efficiency, and eddy current losses all increase with the increase of the number of etched layers. These results can benefit MCET by efficient energy transfer and safe use in metal shielded equipment. 展开更多
关键词 fractal pattern Metal-layer-shield Eddy current Magnetic coupling energy transfer
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Formation and growth of fractal patterns in high energy P^+-implanted silicon and N+Zn-implanted SiO_2/GaAsP during thermal annealing 被引量:1
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作者 吴瑜光 张通和 《Science China(Technological Sciences)》 SCIE EI CAS 1997年第4期343-349,共7页
The fractal patterns in implanted samples are observed. Possible correlation of fractal patterns with the annealing temperature and the electrical activation ratio are given. The formation and growth process of fracta... The fractal patterns in implanted samples are observed. Possible correlation of fractal patterns with the annealing temperature and the electrical activation ratio are given. The formation and growth process of fractal patterns are compared for implanted layers both in silicon and in SiO2/GaAsP during thermal annealing. The mechanism of formation and growth process of fractal pattern is discussed. 展开更多
关键词 fractal patterns P+ high energy IMPLANTATION into silicon Zn + N IMPLANTATION into GAASP thermal annealing TEM observation.
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Fractal Pattern of Gravity Fields and Its Appfication in Bouger Density Determination
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作者 杨新社 王谦身 《Chinese Science Bulletin》 SCIE EI CAS 1993年第7期582-585,共4页
1 Introduction In order to calculate the Bouguer gravity anomaly, the average density (Bouguer density) for the topography whose gravitational influence is to be removed must first be computed. A common approach is to... 1 Introduction In order to calculate the Bouguer gravity anomaly, the average density (Bouguer density) for the topography whose gravitational influence is to be removed must first be computed. A common approach is to estimate this density by minimizing the resulting correlation of the Bouguer gravity anomaly with the topography or other similar but more easily calculated quantities. The underlying assumption of these methods is that the topography is supported by a rigid crust rather than by 展开更多
关键词 fractal pattern of GRAVITY fieldrs free air GRAVITY ANOMALY Bouguer GRAVITY ANOMALY Bouguer density.
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Multifractal Simulation of GeochemicalMap Patterns 被引量:10
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作者 Agterberg Frederik P Geological Survey of Canada, 601 Booth Street, Ottawa, K1A 0E8, Canada 《Journal of China University of Geosciences》 SCIE CSCD 2001年第1期31-39,共9页
Using a simple multifractal model based on the model De Wijs, various geochemical map patterns for element concentration values are being simulated. Each pattern is self-similar on the average in that a similar patter... Using a simple multifractal model based on the model De Wijs, various geochemical map patterns for element concentration values are being simulated. Each pattern is self-similar on the average in that a similar pattern can be derived by application of the multiplicative cascade model used to any small subarea on the pattern. In other experiments, the original, self-similar pattern is distorted by superimposing a 2-dimensional trend pattern and by mixing it with a constant concentration value model. It is investigated how such distortions change the multifractal spectrum estimated by means of the 3-step method of moments. Discrete and continuous frequency distribution models are derived for patterns that satisfy the model of De Wijs. These simulated patterns satisfy a discrete frequency distribution model that as upper bound has a continuous frequency distribution to which it approaches in form when the subdivisions of the multiplicative cascade model are repeated indefinitely. This limiting distribution is lognormal in the center and has Pareto tails. Potentially, this approach has important implications in mineral and oil resource evaluation. 展开更多
关键词 fractals MULTIfractalS model of De Wijs GEOCHEMISTRY map patterns computer simulation.
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Introduction of Multiscaled Longitudinal Vortices by Fractal-Patterned Surface Roughness
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作者 Manami Kosuda Yoshihiro Kubota +1 位作者 Masao Yokoyama Osamu Mochizuki 《Journal of Flow Control, Measurement & Visualization》 2019年第2期120-132,共13页
To determine the type of surface roughness pattern that is suitable for adaptive suppression of the drag of an obstacle, we observed flow structures introduced by such obstacles. Several roughness patterns were tested... To determine the type of surface roughness pattern that is suitable for adaptive suppression of the drag of an obstacle, we observed flow structures introduced by such obstacles. Several roughness patterns were tested: geometric patterns, fractal patterns, reptile-skin patterns, and patterns of circular cylinders arranged in a lattice and in a zigzag manner. A suitable pattern for adaptive control of flow is one that generates longitudinal vortices with nonconstant distances. The preferred instability mode of a laminar boundary layer is expected to be selected automatically from fluctuations involving many frequencies and caused by fractal patterns. Snake- and reptile-skin patterns may have a similar ability as fractal patterns because they consist of multiscale patterns. The longitudinal vortices generated from peculiar positions and concave corners in patterns were observed. The distance between these vortices is not constant because the onset of vortices is at concave corners in fractal patterns. These vortices have differing strengths and easily cause nonlinear interactions, so they can disturb a laminar boundary layer with several higher-harmonic frequencies. The velocity profiles of the laminar boundary-layer flow over the fractal patterns were measured by using hydrogen bubbles. The results show the down-wash flow between the longitudinal vortices, which means that the vortices may effectively suppress the boundary layer separation in an adverse pressure gradient. 展开更多
关键词 FRICTION Drag Reduction Surface ROUGHNESS fractal pattern VORTEX Flow Visualization
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Fractal features of soil profiles under different land use patterns on the Loess Plateau, China 被引量:11
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作者 Lie XIAO Sha XUE +1 位作者 GuoBin LIU Chao ZHANG 《Journal of Arid Land》 SCIE CSCD 2014年第5期550-560,共11页
Fractal theory is becoming an increasingly useful tool to describe soil structure dynamics for a better understanding of the performance of soil systems. Changes in land use patterns significantly affect soil physical... Fractal theory is becoming an increasingly useful tool to describe soil structure dynamics for a better understanding of the performance of soil systems. Changes in land use patterns significantly affect soil physical, chemical and biological properties. However, limited information is available on the fractal characteristics of deep soil layers under different land use patterns. In this study, the fractal dimensions of particle size distribution(PSD) and micro-aggregates in the 0–500 cm soil profile and soil anti-erodibility in the 0–10 cm soil profile for 10 typical land use patterns were investigated in the Zhifanggou Watershed on the Loess Plateau, China. The 10 typical land use patterns were: slope cropland, two terraced croplands, check-dam cropland, woodland, two shrublands, orchard, artificial and natural grasslands. The results showed that the fractal dimensions of PSD and micro-aggregates were all significantly influenced by soil depths, land use patterns and their interaction. The plantations of shrubland, woodland and natural grassland increased the amount of larger micro-aggregates, and decreased the fractal dimensions of micro-aggregates in the 0–40 cm soil profile. And they also improved the aggregate state and aggregate degree and decreased dispersion rate in the 0–10 cm soil profile. The results indicated that fractal theory can be used to characterize soil structure under different land use patterns and fractal dimensions of micro-aggregates were more effective in this regard. The natural grassland may be the best choice for improving soil structure in the study area. 展开更多
关键词 fractal dimension anti-erodibility soil profile land use pattern Loess Plateau
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Rhythmic precipitate patterns and fractal structure
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作者 Rabih F.Sultan 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第1期119-124,共6页
Liesegang patterns of parallel precipitate bands are obtained when solutions containing co-precipitate ions interdiffuse in a 1D gel matrix.The sparingly soluble salt formed,displays a beautiful stratification of disc... Liesegang patterns of parallel precipitate bands are obtained when solutions containing co-precipitate ions interdiffuse in a 1D gel matrix.The sparingly soluble salt formed,displays a beautiful stratification of discs of precipitate perpendicular to the 1D tube axis.The Liesegang structures are analyzed from the viewpoint of their fractal nature.Geometric Liesegang patterns are constructed in conformity with the well-known empirical laws such as the time,band spacing and band width laws.The dependence of the band spacing on the initial concentrations of diffusing(outer)and immobile(inner)electrolytes(A0 and B0,respectively)is taken to follow the Matalon-Packter law.Both mathematical fractal dimensions and box-count dimensions are calculated.The fractal dimension is found to increase with increasing A0 and decreasing B0.We also analyze mosaic patterns with random distribution of crystallites,grown under different conditions than the classical Liesegang gel method,and report on their fractal properties.Finally,complex Liesegang patterns wherein the bands are grouped in multiplets are studied,and it is shown that the fractal nature increases with the multiplicity. 展开更多
关键词 Liesegang · Periodic precipitation · fractals · fractal dimension · Mosaic patterns
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侧限条件下断层破碎岩体变形及渗流侵蚀特性 被引量:4
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作者 孙文斌 田殿金 +3 位作者 马诚 薛彦超 杨灿 朱开鹏 《煤田地质与勘探》 北大核心 2025年第1期193-203,共11页
【目的】我国大部分矿区进入深部开采阶段,复杂的深部水文地质条件和显著增加的隐蔽致灾因素以及断层的存在加大了矿井突水事故的风险。【方法】利用破碎岩石变形–渗流试验系统,研究断层破碎岩体的承压变形与渗流侵蚀特性,通过分析侧... 【目的】我国大部分矿区进入深部开采阶段,复杂的深部水文地质条件和显著增加的隐蔽致灾因素以及断层的存在加大了矿井突水事故的风险。【方法】利用破碎岩石变形–渗流试验系统,研究断层破碎岩体的承压变形与渗流侵蚀特性,通过分析侧限轴向压缩条件下级配组合、饱水状态和渗透水压3个因素对破碎岩体变形-渗流特性的影响,进一步研究破碎岩体岩样颗粒流失特征、空隙结构及渗透参数变化的时变规律。【结果和结论】结果表明:(1)破碎岩样峰值应变随着级配指数n的增加而增大。饱水状态下相同级配的岩样在相同应力下的应变增量值比干燥状态下大。(2)流失颗粒质量与时间的拟合曲线呈指数增长函数关系,流失颗粒质量与侧限轴向应力成反比。次生颗粒质量随着轴向荷载的增大而增大。(3)岩样空隙率的演变趋势与其粒径级配密切相关。级配指数n与岩样的整体空隙率呈正相关关系。加载渗透前后相比,分形维数D与n成反比,细小粒径颗粒的质量增加,大粒径颗粒的质量降低。加载渗透后的岩样分形维数有较大的增量。(4)断层内承压水导升过程宏观上可分为承压水导升初期、导水溃砂通道扩展和发育成熟阶段,细观上可分为岩体浸水软化、错位挤压、变形开裂、破碎剥离的发育过程。研究成果可为断层突水灾害演化规律研究提供试验数据和理论依据。 展开更多
关键词 断层破碎带 颗粒流失 空隙结构 分形特征 变形规律 断层突水
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Visitor flow pattern of Expo 2010 被引量:1
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作者 樊超 郭进利 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第7期66-73,共8页
Expo 2010 Shanghai China was a successful, splendid, and unforgettable event, leaving us with valuable experi- ences. The visitor flow pattern of the Expo is investigated in this paper. The Hurst exponent, the mean va... Expo 2010 Shanghai China was a successful, splendid, and unforgettable event, leaving us with valuable experi- ences. The visitor flow pattern of the Expo is investigated in this paper. The Hurst exponent, the mean value, and the standard deviation of visitor volume indicate that the visitor flow is fractal with long-term stability and correlation as well as obvious fluctuation in a short period. Then the time series of visitor volume is converted into a complex network by using the visibility algorithm. It can be inferred from the topological properties of the visibility graph that the network is scale-free, small-world, and hierarchically constructed, confirming that the time series are fractal and a close relationship exists among the visitor volumes on different days. Furthermore, it is inevitable that will be some extreme visitor volumes in the original visitor flow, and these extreme points may appear in a group to a great extent. All these properties are closely related to the feature of the complex network. Finally, the revised linear regression is performed to forecast the next-day visitor volume based on the previous 10-day data. 展开更多
关键词 fractal pattern time series visibility graph complex network
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分形图案在丝绸服饰设计中的应用与视觉效果研究 被引量:1
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作者 李映锦 《染整技术》 2025年第3期75-77,共3页
分形图案因其独特的自相似性和复杂性,在艺术和设计领域中受到广泛关注。在服饰设计中应用分形图案,能够产生丰富的视觉效果和深层次的美感体验。丝绸具有独特的光泽和质感,为分形图案的表现提供了理想的媒介,因而将分形图案应用于丝绸... 分形图案因其独特的自相似性和复杂性,在艺术和设计领域中受到广泛关注。在服饰设计中应用分形图案,能够产生丰富的视觉效果和深层次的美感体验。丝绸具有独特的光泽和质感,为分形图案的表现提供了理想的媒介,因而将分形图案应用于丝绸服饰设计,能够创新视觉效果。因此,有必要就分形图案在丝绸服饰设计中的应用与视觉效果展开探讨,为服饰设计领域提供新的设计方向。 展开更多
关键词 分形图案 丝绸服饰 视觉效果
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分形加权局部形态模式算法的构建及其应用
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作者 王淳 邢敏 逯洋 《吉林大学学报(信息科学版)》 2025年第3期662-670,共9页
为增强纹理特征提取算法对旋转、光照和尺度变化的鲁棒性,提出分形加权局部形态模式(FWLMP:Fractal Weighted Local Morphological Pattern)。首先,利用分形维数对尺度变化的相对不变性,构建一个尺度不变的描述符。然后使用数学形态学... 为增强纹理特征提取算法对旋转、光照和尺度变化的鲁棒性,提出分形加权局部形态模式(FWLMP:Fractal Weighted Local Morphological Pattern)。首先,利用分形维数对尺度变化的相对不变性,构建一个尺度不变的描述符。然后使用数学形态学中的膨胀、腐蚀和开闭运算对其进行采样分析,利用分形维数图像计算其权重。该算法具有尺度不变性,对旋转和光照变化也具有鲁棒性。为实现对清朝服饰图像的分类,构建了清朝文武官补子图像数据集,并将FWLMP和同类算法在4个公共纹理数据集和自建的清朝文武官补子图像数据集上进行了实验。实验结果表明,FWLMP在纹理图像分类和清朝文武官补子图像分类上具有较好的应用价值。 展开更多
关键词 分形维数 局部形态模式 清朝服饰 数据集 纹理分类
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基于拓扑学的苗族服饰图案分形设计探索与应用
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作者 胡高阳 陈敬玉 《包装工程》 北大核心 2025年第14期432-441,共10页
目的对苗族服饰图案的结构框架进行深入梳理与整合,并在此基础上探索民族纹样的创新设计方式,为现代图案设计领域提供新的设计思路和美学内涵,促进设计的多样性和创新性发展。方法通过分析拓扑基本原理和空间关系,利用拓扑的空间关系进... 目的对苗族服饰图案的结构框架进行深入梳理与整合,并在此基础上探索民族纹样的创新设计方式,为现代图案设计领域提供新的设计思路和美学内涵,促进设计的多样性和创新性发展。方法通过分析拓扑基本原理和空间关系,利用拓扑的空间关系进行图案的多种规则性设计试验,形成创新衍生性图案;通过拓扑基本原理总结苗族服饰图案构图规则,形成苗族服饰图案拓扑构型图,进行整理与分类;将苗族图案拓扑构图规则作为图案分形设计演化规则进一步设计,以苗族“八角星纹”为例生成苗族服饰图案创新再设计。结论得到运用拓扑空间关系进行的图案设计和运用拓扑基本原理生成的苗族服饰图案拓扑构型图,再与分形理论相结合,生成新的民族服饰图案的设计方法,同时为推动民族特色图案的传承与发展提供新思路。 展开更多
关键词 拓扑 分形艺术 苗族 服饰图案
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含构造煤组合体力学特性及分形演化规律研究
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作者 邵秋冬 裴文博 +4 位作者 李其平 任兴鹏 赵鹏翔 田燕彪 郭利 《煤矿安全》 北大核心 2025年第6期123-132,共10页
为研究含构造煤组合体试件的力学特性,以某高瓦斯矿井煤层赋存特征为基础,开展含构造煤组合体加载破裂过程力学特性测试试验,同时通过引入分形维数定量分析含构造煤组合体试件裂隙演化规律。结果表明:含构造煤组合体试件的抗压强度与构... 为研究含构造煤组合体试件的力学特性,以某高瓦斯矿井煤层赋存特征为基础,开展含构造煤组合体加载破裂过程力学特性测试试验,同时通过引入分形维数定量分析含构造煤组合体试件裂隙演化规律。结果表明:含构造煤组合体试件的抗压强度与构造煤厚占比呈负相关关系,构造煤厚占比0~100%对应的抗压强度变化范围为22.94~7.65 MPa;峰值应变和峰值应力点分形维数均与构造煤厚占比呈正相关关系,构造煤厚占比0~100%对应的峰值应变和峰值应力点分形维数变化范围分别为1.21%~1.80%、1.1714~1.1967;含构造煤组合体试件随加载应力的增加其分形维数均表现为逐渐增大的变化规律;构造煤厚占比越大,发生破裂时其对应试件的表面裂隙发育混乱复杂程度更高。 展开更多
关键词 煤岩动力灾害 含构造煤组合体 加载破裂 裂隙演化 破坏形式 分形特征
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基于变化规则L系统分形图的织物图案生成方法
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作者 李凤 杨琪 陈思羽 《毛纺科技》 北大核心 2025年第7期100-105,共6页
针对自动生成的织物图案因不能准确捕捉和迁移风格特征,导致生成的图案整体协调性差、表现不稳定,坐标误差大的问题,提出了基于变化规则L系统分形图的织物图案生成方法。首先设定L系统分形图变化规则,包括绘图、线宽、颜色、分形图合并... 针对自动生成的织物图案因不能准确捕捉和迁移风格特征,导致生成的图案整体协调性差、表现不稳定,坐标误差大的问题,提出了基于变化规则L系统分形图的织物图案生成方法。首先设定L系统分形图变化规则,包括绘图、线宽、颜色、分形图合并变化规则,并将L系统从二维扩展到三维,控制向前、向左、向上3个向量,用于控制织物图案形态;然后调整图案生成时的方向和旋转信息,实现图案真实感仿真;最后构建L系统分形矩阵,依据颜色变化规则,生成由像素排列的图案,结合分形图合并变化规则构建织物图案生成矩阵,并以六角花图案为实例进行应用。结果表明,应用本文方法后任意2个六角花圆心距离最大误差为0.04 cm,六角花图案6个顶点坐标与实际坐标一致,生成图案与理想图案接近。 展开更多
关键词 变化规则 L系统 分形图 纺织服装 图案生成
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基于数字纺织品设计的中国传统蓝印花布纹样创新应用
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作者 张莉 陈秀芳 《武汉纺织大学学报》 2025年第4期62-67,共6页
中国传统蓝印花布纹样蕴藏着深厚的文化底蕴和宝贵的艺术价值,将其应用于现代纺织品,有利于活化传统纺织文化。文章基于分形软件JWildfire,利用仿射变换和函数生成图案后,导入蓝印花布纹样“五福捧寿”和“凤戏牡丹”与其结合,从而对蓝... 中国传统蓝印花布纹样蕴藏着深厚的文化底蕴和宝贵的艺术价值,将其应用于现代纺织品,有利于活化传统纺织文化。文章基于分形软件JWildfire,利用仿射变换和函数生成图案后,导入蓝印花布纹样“五福捧寿”和“凤戏牡丹”与其结合,从而对蓝印花布纹样进行再设计。渲染后得到既保留纹样原有造型、又体现分形特点的数字图案,且结构精细,构图方式和色彩层次更加丰富。将图案通过数码印花可制作双面同花同色丝巾,或通过Style3D软件设计数字服装。设计过程全部实现数字化,设计产品将传统纹样与现代科技相结合,具有创新性、时尚性和实用性。 展开更多
关键词 蓝印花布 传统纹样 分形软件 数码印花丝巾 Style3D 数字服装
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Growth pattern of reed in Caogang Lake,Huanghuaihai Plain,China 被引量:2
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作者 Cai Qing hua Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China Wu Gang Department of Systems Ecology, Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1999年第1期104-109,共6页
The researches about reed growth were mainly concentrated on seasonal dynamics, investigation of reed resource, and comparison of different ecotypes of reed. By means of fractal geometric theory of non linear science... The researches about reed growth were mainly concentrated on seasonal dynamics, investigation of reed resource, and comparison of different ecotypes of reed. By means of fractal geometric theory of non linear science, the fractal character of growth pattern of reed, for the purpose of quantitatively exploring the mechanism of reed growth was studied. The way to calculate fractal dimension of reed growth is box dimension (BD) and information dimension (ID). The results showed that the difference between two samplings in May and those among three samplings in June and later were not remarkable for both BD or ID. It was noted that the difference between samplings in and after May is significant. It was demonstrated that the fractal dimension of size distribution of reed ranged from 0 6235 to 0 8761 The distribution pattern could be statistically divided as two significant periods: the size of reed is quite well distributed at the beginning of reed growth (fractal dimension>0 8), but is irregular in the middle and later growth season (fractal dimension<0 7). These results are benefit to reach the goal of rational use of reed resources and to protect the biodiversity in wetland ecosystem. 展开更多
关键词 fractal pattern GROWTH REED wetland ecosystem.
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Experimental studies on the evolution process of microcrack patterns in concrete samples con-taining hard inclusions 被引量:2
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作者 许昭永 王彬 +2 位作者 赵晋明 胡毅力 梅世蓉 《Acta Seismologica Sinica(English Edition)》 CSCD 1997年第3期106-112,共7页
Under biaxial pressure, the microcrack patterns of concrete samples with hard inclusion are as followings: Microcracks generate around the sample at the early pressured period, and gap is formed in the middle part wit... Under biaxial pressure, the microcrack patterns of concrete samples with hard inclusion are as followings: Microcracks generate around the sample at the early pressured period, and gap is formed in the middle part with the increase of σ 1; microcrack gap is becoming smaller gradually with σ 1 increase again; microcracks become active within the original gap, but they in an original active area become small. Approaching the main fracture, microcracks form as a belt and jump back and forth in the belt. The spatial fractal D s of microcracks changes from small to big, but turns decrease when approaching the main fracture. All of the features were seldom mentioned in the past experiment, however, which have some similarities with the long seismicity patterns before strong earthquakes. In this paper, Lancang Gengma earthquake was taken as an example to analyse.〖KH*2D] 展开更多
关键词 hard inclusion MICROCRACKS activity pattern fractal Lancang Gengma earthquake
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Dense Fractal Networks, Trends, Noises and Switches in Homeostasis Regulation of Shannon Entropy for Chromosomes’ Activity in Living Cells for Medical Diagnostics
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作者 Nikolay E. Galich 《Applied Mathematics》 2013年第11期30-41,共12页
We analyze correlations and patterns of oxidative activity of 3D DNA at DNA fluorescence in complete sets of chromosomes in neutrophils of peripheral blood. Fluorescence of DNA is registered by method of flow cytometr... We analyze correlations and patterns of oxidative activity of 3D DNA at DNA fluorescence in complete sets of chromosomes in neutrophils of peripheral blood. Fluorescence of DNA is registered by method of flow cytometry with nanometer spatial resolution. Experimental data present fluorescence of many ten thousands of cells, from different parts of body in each population, in various blood samples. Data is presented in histograms as frequency distributions of flashes in the dependence on their intensity. Normalized frequency distribution of information in these histograms is used as probabilistic measure for definition of Shannon entropy. Data analysis shows that for this measure of Shannon entropy common sum of entropy, i.e. total entropy E, for any histogram is invariant and has identical trends of changes all values of E (r) = lnr at reduction of rank r of histogram. This invariance reflects informational homeostasis of chromosomes activity inside cells in multi-scale networks of entropy, for varied ranks r. Shannon entropy in multi-scale DNA networks has much more dense packing of correlations than in “small world” networks. As the rule, networks of entropy differ by the mix of normal D 2 and abnormal D > 2 fractal dimensions for varied ranks r, the new types of fractal patterns and hinges for various topology (fractal dimension) at different states of health. We show that all distributions of information entropy are divided on three classes, which associated in diagnostics with a good health or dominants of autoimmune or inflammatory diseases. This classification based on switching of stability at transcritical bifurcation in homeostasis regulation. We defined many ways for homeostasis regulation, coincidences and switching patterns in branching sequences, the averages of H&ouml;lder for deviations of entropy from homeostasis at different states of health, with various saturation levels the noises of entropy at activity of all chromosomes in support regulation of homeostasis. 展开更多
关键词 Abnormal fractals DNA ACTIVITY and Shannon Information ENTROPY fractal patterns and Fragmentation Informational HOMEOSTASIS Saturations of CHROMOSOMAL Correlations Multi-Scale fractal NETWORKS of Shannon ENTROPY
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