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Fractal analysis of major faults and fractal dimension of lineaments in the Indo-Gangetic Plain on a regional scale
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作者 Vipin Chauhan Jagabandhu Dixit 《Earthquake Science》 2024年第2期107-121,共15页
The Indo-Gangetic Plain(IGP)is one of the most seismically vulnerable areas due to its proximity to the Himalayas.Geographic information system(GIS)-based seismic characterization of the IGP was performed based on the... The Indo-Gangetic Plain(IGP)is one of the most seismically vulnerable areas due to its proximity to the Himalayas.Geographic information system(GIS)-based seismic characterization of the IGP was performed based on the degree of deformation and fractal dimension.The zone between the Main Boundary Thrust(MBT)and the Main Central Thrust(MCT)in the Himalayan Mountain Range(HMR)experienced large variations in earthquake magnitude,which were identified by Number-Size(NS)fractal modeling.The central IGP zone experienced only moderate to low mainshock levels.Fractal analysis of earthquake epicenters reveals a large scattering of earthquake epicenters in the HMR and central IGP zones.Similarly,the fault fractal analysis identifies the HMR,central IGP,and south-western IGP zones as having more faults.Overall,the seismicity of the study region is strong in the central IGP,south-western IGP,and HMR zones,moderate in the western and southern IGP,and low in the northern,eastern,and south-eastern IGP zones. 展开更多
关键词 geospatial analysis fractal modeling seismicity pattern fractal dimension
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Computational Quantification of Map Projection Distortion by Fractal Dimension of Coastlines
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作者 Franklin Lee 《Journal of Applied Mathematics and Physics》 2024年第5期1890-1903,共14页
Maps, essential tools for portraying the Earth’s surface, inherently introduce distortions to geographical features. While various quantification methods exist for assessing these distortions, they often fall short w... Maps, essential tools for portraying the Earth’s surface, inherently introduce distortions to geographical features. While various quantification methods exist for assessing these distortions, they often fall short when evaluating actual geographic features. In our study, we took a novel approach by analyzing map projection distortion from a geometric perspective. We computed the fractal dimensions of different stretches of coastline before and after projection using the divide-and-conquer algorithm and image processing. Our findings revealed that map projections, even when preserving basic shapes, inevitably stretch and compress coastlines in diverse directions. This analysis method provides a more realistic and practical way to measure map-induced distortions, with significant implications for cartography, geographic information systems (GIS), and geomorphology. By bridging the gap between theoretical analysis and real-world features, this method greatly enhances accuracy and practicality when evaluating map projections. 展开更多
关键词 Map Projection Distortion COASTLINE fractal dimension CARTOGRAPHY Geographic Information Systems
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量化三维网格模型复杂度的Fractal Dimension^(+)方法
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作者 孙鸣 丁展 《金陵科技学院学报》 2024年第2期1-11,73,共12页
对三维网格模型复杂度的评估及应用进行研究,提出基于Fractal Dimension^(+)方法量化三维网格模型复杂度。该方法利用分形几何学的分形维度来确定三维网格模型的不规则性;为了全面量化复杂度并且提高量化的准确性和可信度,在分形维度算... 对三维网格模型复杂度的评估及应用进行研究,提出基于Fractal Dimension^(+)方法量化三维网格模型复杂度。该方法利用分形几何学的分形维度来确定三维网格模型的不规则性;为了全面量化复杂度并且提高量化的准确性和可信度,在分形维度算法中添加孔隙比和亏格数的概念,全面考虑介质内部空间分布和几何结构的连接性以及孔洞分布的信息。对大量三维网格模型进行实验,结果表明Fractal Dimension^(+)方法可以有效计算出准确的复杂度。 展开更多
关键词 三维网格模型 模型复杂度 fractal dimension^(+) 分形维度 孔隙比 亏格
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Novel Path Counting-Based Method for Fractal Dimension Estimation of the Ultra-Dense Networks
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作者 Farid Nahli Alexander Paramonov +4 位作者 Naglaa F.Soliman Hussah Nasser AlEisa Reem Alkanhel Ammar Muthanna Abdelhamied A.Ateya 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期561-572,共12页
Next-generation networks,including the Internet of Things(IoT),fifth-generation cellular systems(5G),and sixth-generation cellular systems(6G),suf-fer from the dramatic increase of the number of deployed devices.This p... Next-generation networks,including the Internet of Things(IoT),fifth-generation cellular systems(5G),and sixth-generation cellular systems(6G),suf-fer from the dramatic increase of the number of deployed devices.This puts high constraints and challenges on the design of such networks.Structural changing of the network is one of such challenges that affect the network performance,includ-ing the required quality of service(QoS).The fractal dimension(FD)is consid-ered one of the main indicators used to represent the structure of the communication network.To this end,this work analyzes the FD of the network and its use for telecommunication networks investigation and planning.The clus-ter growing method for assessing the FD is introduced and analyzed.The article proposes a novel method for estimating the FD of a communication network,based on assessing the network’s connectivity,by searching for the shortest routes.Unlike the cluster growing method,the proposed method does not require multiple iterations,which reduces the number of calculations,and increases the stability of the results obtained.Thus,the proposed method requires less compu-tational cost than the cluster growing method and achieves higher stability.The method is quite simple to implement and can be used in the tasks of research and planning of modern and promising communication networks.The developed method is evaluated for two different network structures and compared with the cluster growing method.Results validate the developed method. 展开更多
关键词 Cluster growing CONNECTIVITY dense networks fractal dimension network structure shortest route quality of service
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Fractal dimension for porous metal materials of FeCrAl fiber 被引量:1
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作者 王建忠 奚正平 +3 位作者 汤慧萍 黄卫东 朱纪磊 敖庆波 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第4期1046-1051,共6页
The FeCrA1 fiber was used to prepare porous metal materials with air-laid technology, and then followed by sintering at 1300 ℃ for a holding period of 2 h in the vacuum. In addition, a novel fractal soft, which was d... The FeCrA1 fiber was used to prepare porous metal materials with air-laid technology, and then followed by sintering at 1300 ℃ for a holding period of 2 h in the vacuum. In addition, a novel fractal soft, which was developed based on the fractal theory and the computer image processing technology, was explored to describe the pore structure of porous metal materials. Furthermore, the fractal dimension of pore structure was calculated by the soft and the effects of magnification and porosity on ffactal dimension were also discussed. The results show that the fractal dimension decreases with increase in the magnification, while it increases continuously with the porosity enhancing. The interrelationship between the fractal dimension and the magnification or porosity can be presented by the equation of D=α_0exp(-x/α_1)+α_2和D=k_2-(k_1-k_2)/[1+exp((θ-k_0)/k_3)], respectively. 展开更多
关键词 porous metal materials FeCrA1 fiber fractal dimension POROSITY MAGNIFICATION
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Classification of forearm action surface EMG signals based on fractal dimension 被引量:1
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作者 胡晓 王志中 任小梅 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期324-329,共6页
Surface electromyogram (EMG) signals were identified by fractal dimension.Two patterns of surface EMG signals were acquired from 30 healthy volunteers' right forearm flexor respectively in the process of forearm su... Surface electromyogram (EMG) signals were identified by fractal dimension.Two patterns of surface EMG signals were acquired from 30 healthy volunteers' right forearm flexor respectively in the process of forearm supination (FS) and forearm pronation (FP).After the raw action surface EMG (ASEMG) signal was decomposed into several sub-signals with wavelet packet transform (WPT),five fractal dimensions were respectively calculated from the raw signal and four sub-signals by the method based on fuzzy self-similarity.The results show that calculated from the sub-signal in the band 0 to 125 Hz,the fractal dimensions of FS ASEMG signals and FP ASEMG signals distributed in two different regions,and its error rate based on Bayes decision was no more than 2.26%.Therefore,the fractal dimension is an appropriate feature by which an FS ASEMG signal is distinguished from an FP ASEMG signal. 展开更多
关键词 action surface electrolnyogram (ASEMG) signal: fractal dimension wavelet packet transform(WPT) fuzzy self-similarity Bayes decision
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Study on the Spatial Pattern Changes of Land Use Based on Fractal Dimensions in Tianjin New Coastal Area 被引量:3
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作者 白新萍 《Agricultural Science & Technology》 CAS 2011年第6期879-882,919,共5页
[Objective] The aim was to discuss the spatial pattern changes of land use in Tianjin new coastal area based on fractal dimensions.[Method] By dint of remote and geographic information system technology to obtain the ... [Objective] The aim was to discuss the spatial pattern changes of land use in Tianjin new coastal area based on fractal dimensions.[Method] By dint of remote and geographic information system technology to obtain the data of urban land use in new coastal area from 1993 to 2008,the boundary dimension,radius dimension and information dimension of each land use type were calculated based on fractal dimension.In addition,the revealed land use spatial dimension changes characteristics were analyzed.[Result] The spatial distribution of each land use type in new costal area had distinct fractal characteristics.And,the amount and changes of three types of dimension values effectively revealed the changes of complicatedness,centeredness and evenness of spatial pattern of land use in the study area.The boundary dimension of unused land and salty earth increased incessantly,which suggested its increasing complicatedness.The boundary of the port and wharf and shoal land was getting simpler.The radius dimension of the cultivated land was larger than 2,which suggested that its area spread from center to the surroundings;the one in salty land and waters distributed evenly within different radius space to the center of the city;the one in other land use types reduced gradually from center to the surroundings.The information dimension value in the woodland and orchard land,unused land and shoal land was small,and was in obvious concentrated distribution;the spatial distribution of cultivated and salty land concentrated in the outside area;the construction area in the port and wharf spread gradually on the basis of original state;the spatial distribution of waters and residents and mines were even.[Conclusion] Applying fractal dimensions to the study of spatial pattern changes of urban land use can make up for some disadvantages in classical urban spatial pattern quantitative research,which has favorable practical value. 展开更多
关键词 Land use fractal dimension Boundary dimension Radial dimension Information dimension Tianjin New Coastal Area
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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:29
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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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Introducing Fractal Dimension to Estimation of Soil Sensitivity to Preferential Flow 被引量:12
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作者 CHENGZHUHUA ZHANGJIABAQ 《Pedosphere》 SCIE CAS CSCD 2002年第3期201-206,共6页
Food dye Brilliant Blue was introduced as the tracer in a dye-tracing experiment to obtain dye profile patterns of sandy loam soil, aeolian sandy soil, percolating paddy soil and permeable paddy soil. The dyed soil pr... Food dye Brilliant Blue was introduced as the tracer in a dye-tracing experiment to obtain dye profile patterns of sandy loam soil, aeolian sandy soil, percolating paddy soil and permeable paddy soil. The dyed soil profiles were then photographed and the photos were scanned into a computer. Edited with certain software, only the dyed areas were left on the profile photos, which indicted the preferential flow paths for water and solute transport. Fractal dimensions of the dye patterns were calculated according to Arnold's function. Soil particle size distribution was analyzed by pipette method. The regression analysis showed that there was significant relationship between soil clay content and fractal dimension D of the dye pattern of soil profile. Based on the experiment results, the possibility of introducing fractal dimension to estimation of soil sensitivity to preferential flow is discussed. 展开更多
关键词 dye tracing fractal dimension preferential flow sensitivity soil claycontent
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Volume fractal dimension of soil particles and relationships with soil physical-chemical properties and plant species diversity in an alpine grassland under different disturbance degrees 被引量:21
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作者 YanYan LIU YanMing GONG +1 位作者 Xin WANG YuKun HU 《Journal of Arid Land》 SCIE CSCD 2013年第4期480-487,共8页
Fractal geometry is an important method in soil science,and many studies have used fractal theory to examine soil properties and the relationships with other eco-environmental factors.However,there have been few studi... Fractal geometry is an important method in soil science,and many studies have used fractal theory to examine soil properties and the relationships with other eco-environmental factors.However,there have been few studies examining soil particle volume fractal dimension in alpine grasslands.To study the volume fractal dimension of soil particles (D) and its relationships with soil salt,soil nutrient and plant species diversity,we conducted an experiment on an alpine grassland under different disturbance degrees:non-disturbance (N0),light disturbance (L),moderate disturbance (M) and heavy disturbance (H).The results showed that (1) Ds varied from 2.573 to 2.635 among the different disturbance degrees and increased with increasing degrees of disturbance.(2) Shannon-Wiener diversity index,Pielou's evenness index and Margalef richness index reached their highest values at the M degree,indicating that moderate disturbance is beneficial to the increase of plant species diversity.(3) In the L and M degrees,there was a significant positive correlation between D and clay content and a significant negative correlation between D and soil organic matter (SOM).In the H degree,D was significantly and positively correlated with total salt (TS).The results suggested that to a certain extent,D can be used to characterize the uniformity of soil texture in addition to soil fertility characteristics.(4) For the L degree,there was a significant negative correlation between D and the Shannon-Wiener diversity index; while for the M degree,there was a significant negative correlation between D and Pielou's evenness index. 展开更多
关键词 alpine grassland disturbance degree volume fractal dimension of soil particles species diversity
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Relevance between abutment pressure and fractal dimension of crack network induced by mining 被引量:8
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作者 Gao Mingzhong Jin Wencheng +1 位作者 Dai Zhixu Xie Jing 《International Journal of Mining Science and Technology》 SCIE EI 2013年第6期925-930,共6页
Based on the geological conditions of coal mining face No.15-14120 at No.8 mine of Pingdingshan coal mining group,the real-time evolution of coal-roof crack network with working face advancing was collected with the h... Based on the geological conditions of coal mining face No.15-14120 at No.8 mine of Pingdingshan coal mining group,the real-time evolution of coal-roof crack network with working face advancing was collected with the help of intrinsically safe borehole video instrument.And according to the geology of this working face,a discrete element model was calculated by UDEC.Combining in situ experimental data with numerical results,the relationship between the fractal dimension of boreholes'wall and the distribution of advanced abutment pressure was studied under the condition of mining advance.The results show that the variation tendency of fractal dimension and the abutment pressure has the same characteristic value.The distance between working face and the peak value of the abutment pressure has a slight increasing trend with the advancing of mining-face.When the working face is set as the original point,the trend of fractal dimension from the far place to the origin can be divided into three phases:constant,steady increasing and constant.And the turning points of these phases are the max-influencing distance(50 m)and peak value(15 m)of abutment pressure. 展开更多
关键词 BOREHOLES Coal mines Cracks Finite difference method fractal dimension
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Fractal Characteristics and Fractal Dimension Measurement on Broken Surfaces of Aluminum Electric Porcelain 被引量:5
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作者 杨志远 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第1期37-41,共5页
The characteristics of broken surfaces were r esearched by a scanning electron microscope (SEM) and a reflection microscope, a nd the fractal dimensions of broken surfaces were measured by the Slit Island me thod. Th... The characteristics of broken surfaces were r esearched by a scanning electron microscope (SEM) and a reflection microscope, a nd the fractal dimensions of broken surfaces were measured by the Slit Island me thod. The experimental results indicate that the broken surface of aluminum elec tric porcelain is a fractal body in statistics, and the fractal dimensions of br oken surfaces are different with the different amplification multiple value.In a ll of measured fractal dimensions,both of values measured in 100× under reflect ion microscope and in 500× under SEM are maximum, whereas the values measur ed in 63× under reflection microscope and in 2000× under SEM are obviously min imum. The fractal dimensions of broken surfaces are also affected by the degrees of gray comparison and the kinds of measuring methods. The relationships betwee n the fractal dimensions of broken surfaces and porcelain bend strengths are tha t they are in positive correlation on the low multiples and in negative correlat ion on the high multiples. 展开更多
关键词 broken surface fractal dimension Slit Island m ethod electric porcelain
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Bubble size fractal dimension,gas holdup,and mass transfer in a bubble column with dual internals 被引量:4
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作者 Xiao Xu Junjie Wang +4 位作者 Qiang Yang Lei Wang Hao Lu Honglai Liu Hualin Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第12期2968-2976,共9页
As the scale of residual oil treatment increases and cleaner production improves in China,slurry bubble column reactors face many challenges and opportunities for residual oil hydrogenation technology.The internals de... As the scale of residual oil treatment increases and cleaner production improves in China,slurry bubble column reactors face many challenges and opportunities for residual oil hydrogenation technology.The internals development is critical to adapt the long-term stable operation.In this paper,the volumetric mass transfer coefficient,gas holdup and bubble size in a gas-liquid up-flow column are studied with two kinds of internals.The gas holdup and volumetric mass transfer coefficient increase by 120% and 42% when the fractal dimension of bubbles increases from 0.56 to 2.56,respectively.The enhanced mass transfer processing may improve the coke suppression ability in the slurry reactor for residual oil treatment.The results can be useful for the exploration of reacting conditions,scale-up strategies,and oil adaptability.This work is valuable for the design of reactor systems and technological processes. 展开更多
关键词 Gas-liquid reactor fractal dimension Mass transfer Bubble column
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Characterizing the Spheroidization Grade and Strength of 15CrMo Steel through Determining Fractal Dimension 被引量:3
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作者 LIU Changjun DONG Leiyun JIANG Xiaodong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第4期826-831,共6页
The fractal dimension(FD) of surfaces has been widely used to characterize the properties of materials.However,most of the previous researches were concentrated on the correlation between the FD of surfaces and mech... The fractal dimension(FD) of surfaces has been widely used to characterize the properties of materials.However,most of the previous researches were concentrated on the correlation between the FD of surfaces and mechanical properties of materials,such as impact energy and fracture toughness,etc.The aim of this paper is to characterize the spheroidization grade and strength of 15CrMo steel through determination of FD of cementite phase on the basis of two-dimension microstructural image.Two methods,namely slit-island method(SIM) and box-counting method(BCM),are used to determine the value of FD.It is found that the FD value evaluated by using BCM is generally higher than that evaluated by SIM.This phenomenon may be due to the difference in the principles used in different methods.Whether SIM or BCM is used,the spheroidization grade in 15CrMo steel linearly increases with decreasing the value of FD.The relationship between the FD value,D,and spheroidization grade,Sg,can be approximately expressed as D≌-0.11Sg+A,where A is a constant value which is depended on the evaluation method.Both the ultimate strength and the yielding strength of 15CrMo steel increase with increasing FD of cementite phase.There may be a common relationship between the FD of cementite phase and strength of 15CrMo steel.When the FD of cementite phase in 15CrMo steel is determined,the strength of this steel can be evaluated.The present paper can provide a novel method to evaluate the strength and spheroidization grade of carbon steel through determination of fractal dimension(FD) of cementite phase. 展开更多
关键词 spheroidization grade fractal dimension STRENGTH cementite phase
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Fractal Dimension of Voice-Signal Waveforms 被引量:3
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作者 Xie Yu qiong, Wen Zhi xiong Non linear Science Center , Wuhan University,Wuhan 430072,Hubei,China 《Wuhan University Journal of Natural Sciences》 CAS 2002年第4期399-402,共4页
The fractal dimension is one important parameter that characterizes waveforms. In this paper, we derive a new method to calculate fractal dimension of digital voice-signal waveforms. We show that fractal dimension is ... The fractal dimension is one important parameter that characterizes waveforms. In this paper, we derive a new method to calculate fractal dimension of digital voice-signal waveforms. We show that fractal dimension is an efficient tool for speaker recognition or speech recognition. It can be used to identify different speakers or distinguish speech. We apply our results to Chinese speaker recognition and numerical experiment shows that fractal dimension is an efficient parameter to characterize individual Chinese speakers. We have developed a semiautomatic voiceprint analysis system based on the theory of this paper and former researches. 展开更多
关键词 Key words fractal dimension voiceprint analysis speaker recognition speech recognition biometric authentication
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Fractal Dimension of Pore Structure of Combustible Cartridge Cases 被引量:5
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作者 肖乐勤 邹伟伟 +2 位作者 李煜 郭德惠 周伟良 《Defence Technology(防务技术)》 CAS 2012年第2期109-113,共5页
A fractal pore structure model of combustible cartridge cases was established by virtue of the fractal geometry. Pore structure information, such as backbone fractal dimension and pore fractal dimension, of four kinds... A fractal pore structure model of combustible cartridge cases was established by virtue of the fractal geometry. Pore structure information, such as backbone fractal dimension and pore fractal dimension, of four kinds of combustible cartridge case were obtained by mercury intrusion porosimetry (MIP) . The formation mechanism of fractal pore structure of combustible cartridge was studied. The results show that the backbone fractal dimension consists of the component and influenced by the component number and size of components; the pore percolation fractal dimension reflects the pore structures of components; and the fractal dimension of pore structure is positively relative to the tensile strength of combustible cartridge case. 展开更多
关键词 physical chemistry combustible cartridge case pore structure fractal dimension POROSITY
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Experimental validation of a signal-based approach for structural earthquake damage detection using fractal dimension of time frequency feature 被引量:2
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作者 Tao Dongwang Mao Chenxi +1 位作者 Zhang Dongyu Li Hui 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第4期671-680,共10页
This article extends a signal-based approach formerly proposed by the authors, which utilizes the fractal dimension of time frequency feature (FDTFF) of displacements, for earthquake damage detection of moment resis... This article extends a signal-based approach formerly proposed by the authors, which utilizes the fractal dimension of time frequency feature (FDTFF) of displacements, for earthquake damage detection of moment resist frame (MRF), and validates the approach with shaking table tests. The time frequency feature (TFF) of the relative displacement at measured story is defined as the real part of the coefficients of the analytical wavelet transform. The fractal dimension (FD) is to quantify the TFF within the fundamental frequency band using box counting method. It is verified that the FDTFFs at all stories of the linear MRF are identical with the help of static condensation method and modal superposition principle, while the FDTFFs at the stories with localized nonlinearities due to damage will be different from those at the stories without nonlinearities using the reverse-path methodology. By comparing the FDTFFs of displacements at measured stories in a structure, the damage-induced nonlinearity of the structure under strong ground motion can be detected and localized. Finally shaking table experiments on a 1:8 scale sixteen-story three-bay steel MRF with added frictional dampers, which generate local nonlinearities, are conducted to validate the approach. 展开更多
关键词 earthquake damage detection time frequency feature fractal dimension signal-based shaking table test frictional damper
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A new multiple-factor clustering method considering both box fractal dimension and orientation of joints 被引量:2
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作者 Tiexin Liu Annan Jiang +2 位作者 Jianhui Deng Jun Zheng Zhenghu Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第2期366-376,共11页
The paper proposes a new multiple-factor clustering method(NMFCM)with consideration of both box fractal dimension(BFD)and orientation of joints.This method assumes that the BFDs of different clusters were uneven,and c... The paper proposes a new multiple-factor clustering method(NMFCM)with consideration of both box fractal dimension(BFD)and orientation of joints.This method assumes that the BFDs of different clusters were uneven,and clustering was performed by redistributing the joints near the boundaries of clusters on a polar map to maximize an index for estimating the difference of the BFD(DBFD).Three main aspects were studied to develop the NMFCM.First,procedures of the NMFCM and reasonableness of assumptions were illustrated.Second,main factors affecting the NMFCM were investigated by numerical simulations with disk joint models.Finally,two different sections of a rock slope were studied to verify the practicability of the NMFCM.The results demonstrated that:(1)The NMFCM was practical and could effectively alleviate the problem of hard boundary during clustering;(2)The DBFD tended to increase after the improvement of clustering accuracy;(3)The improvement degree of the NMFCM clustering accuracy was mainly influenced by three parameters,namely,the number of clusters,number of redistributed joints,and total number of joints;and(4)The accuracy rate of clustering could be effectively improved by the NMFCM. 展开更多
关键词 Joint clustering Box fractal dimension(BFD) ORIENTATION Hard boundary
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Fractal dimensions of flocs between clay particles and HAB organisms 被引量:1
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作者 王洪亮 俞志明 +1 位作者 曹西华 宋秀贤 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第3期656-663,共8页
The impact of harmful algal blooms (HABs) on public health and related economics have been increasing in many coastal regions of the world. Sedimentation of algal cells through flocculation with clay particles is a ... The impact of harmful algal blooms (HABs) on public health and related economics have been increasing in many coastal regions of the world. Sedimentation of algal cells through flocculation with clay particles is a promising strategy for controlling HABs. Previous studies found that removal efficiency (RE) was influenced by many factors, including clay type and concentration, algal growth stage, and physiological aspects of HAB cells. To estimate the effect of morphological characteristics of the aggregates on HAB cell removal, fractal dimensions were measured and the RE of three species of HAB organism, Heterosigma akashiwo, Alexandrium tamarense, and Skeletonema eostatum, by original clay and modified clay, was determined. For all HAB species, the modified clay had a higher RE than original clay. For the original clay, the two-dimensional fractal dimension (D2) was 1.92 and three-dimensional ffactal dimension (D3) 2.81, while for the modified clay, D2 was 1.84 and D3 was 2.50. The addition of polyaluminum chloride (PAC1) lead to a decrease of the repulsive barrier between clay particles, and resulted in lower D2 and D3. Due to the decrease of D3, and the increase of the effective sticking coefficient, the flocculation rate between modified clay particles and HAB organisms increased, and thus resulted in a high RE. The fractal dimensions of flocs differed in HAB species with different cell morphologies. For example, Alexandrium tamarense cells are ellipsoidal, and the D3 and D2 of flocs were the highest, while for Skeletonema costatum, which has filamentous cells, the D3 and D2 of flocs were the lowest. 展开更多
关键词 harmful algal blooms modified clay fractal dimensions Heterosigma akashiwo Alexandrium tamarense Skeletonema costatum
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INFLUENCE OF SERIES OF SQUARE GRIDS ON FRACTAL DIMENSIONS-A Case Study of Mountains of China's Mainland 被引量:1
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作者 ZHUXiao-hua CAIYun-long 《Chinese Geographical Science》 SCIE CSCD 2004年第1期9-14,共6页
MANDELBROT enunciated the uncertainty of the length of a coastline in his paper "How long is the coastline of Britain?" published in Science in 1967. The fractal concept was presented for the first time in t... MANDELBROT enunciated the uncertainty of the length of a coastline in his paper "How long is the coastline of Britain?" published in Science in 1967. The fractal concept was presented for the first time in that paper and has been applied to many fields ever since. Although fractal dimensions of lots of phenomena were calculated by the box-counting method,the quantitative influence of series of square grids on them is ignored. The issue is systematically discussed as a case study of the mountains of China′s Mainland in this paper. And some significant conclusions are drawn as follows: 1) Although the fractal character objectively exists in the mountains of China′s Mainland,and it does not vary with the changes of series of square grids,the fractal dimensions of the mountains of China′s Mainland are different with these changes. 2) The fractal dimensions of the mountains of China′s Mainland vary with the average lengths of sides of series of square grids. The fractal dimension of the mountains of China′s Mainland is the function of the average length of side of square grid. They conform to the formula D=f(r) (where D is the fractal dimension,and r is the average length of side of square grid). 3) Different dots of data collection can affect the fractal dimension of the mountains of China′s Mainland. 4) The same range of length of side of square grid and dots of data collection can ensure the comparison of fractal dimensions of the mountains of China′s Mainland. The research is helpful to get the more understanding of fractal and fractal dimension,and ensure that the fractal studies would be scientific. 展开更多
关键词 fractal fractal dimension series of square grids China's Mainland
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