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Hierarchical fractal structure of perfect single-layer graphene
T. Zhang, K. Ding
《机械工程前沿(英文)》 2013年 第8卷 第4期 页码 371-382 doi: 10.1007/s11465-013-0279-1
The atomic lattice structure of perfect single-layer graphene that can actually be regarded as a kind of hierarchical fractal structure from the perspective of fractal geometry was studied for the first time. Three novel and special discoveries on hierarchical fractal structure and sets were unveiled upon examination of the regular crystal lattices of the single-layer graphene. The interior fractal-type structure was discovered to be the fifth space-filling curve from physical realm. Two efficient methods for calculating the fractal dimension of this fresh member was also provided. The outer boundary curve had a fractal dimension equal to one, and a multi-fractal structure from a naturally existing material was found for the first time. A series of strict self-similar hexagons comprised a rotating fractal set. These hexagons slewed at a constant counterclockwise angle of 19.1° when observed from one level to the next higher level. From the perspective of fractal geometry, these pioneering discoveries added three new members to the existing regular fractal structures and sets. A fundamental example of a multi-fractal structure was also presented.
关键词: hierarchical fractal structure fractal dimension the fifth space-filling curve multi-fractal structure
PD pattern recognition based on multi-fractal dimension in GIS
ZHANG Xiaoxing, YAO Yao, TANG Ju, ZHOU Qian, XU Zhongrong
《机械工程前沿(英文)》 2008年 第3卷 第3期 页码 270-275 doi: 10.1007/s11465-008-0042-1
关键词: substation high-speed discharge centrobaric network ultra-high frequency
Aggregating structure in coal water slurry studied by eDLVO theory and fractal dimension
Qiang LI, Qian WANG, Jian HOU, Jiansheng ZHANG, Yang ZHANG
《能源前沿(英文)》 2023年 第17卷 第2期 页码 306-316 doi: 10.1007/s11708-021-0736-1
关键词: coal water slurry extended DLVO (eDLVO) fractal dimension stability
涂承媛,曾衍钧
《中国工程科学》 2003年 第5卷 第8期 页码 45-49
简要介绍了非线性科学中的分形维方法和信息熵方法及其用于房颤信息的处理和分析,计算了未房颤时P波的及房颤时f波的格子维和信息熵,特别是,比较了未房颤时和发生房颤时的相关计算结果的显著差别,从而很容易判断是否发生了房颤。
A new proof of Honeycomb Conjecture by fractal geometry methods
Tong ZHANG, Kai DING
《机械工程前沿(英文)》 2013年 第8卷 第4期 页码 367-370 doi: 10.1007/s11465-013-0273-7
Based on fractal geometry, we put forward a concise and straightforward method to prove Honeycomb Conjecture—a classical mathematic problem. Hexagon wins the most efficient covering unit in the two- dimensional space, compared with the other two covering units—triangle and square. From this point of view, honeycomb is treated as a hierarchical fractal structure that fully fills the plane. Therefore, the total side length and area are easily calculated and from the results, the covering efficiency of each possible unit is provided quantitatively.
关键词: Honeycomb Conjecture fractal geometry hierarchical fractal structure
《结构与土木工程前沿(英文)》 2021年 第15卷 第6期 页码 1317-1336 doi: 10.1007/s11709-021-0763-3
关键词: square concrete filled tubes confine-stiffening confine-strengthening fractal cracking fracture
Copper fractal growth during recycling from waste printed circuit boards by slurry electrolysis
《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1405-7
• Copper fractal growth was observed during WPCBs recycling by slurry electrolysis.
关键词: Dendritic copper Fractal growth WPCBs Slurry electrolysis
Fractal characteristic evaluation and interpolation reconstruction for surface topography of drilled
《机械工程前沿(英文)》 2021年 第16卷 第4期 页码 840-854 doi: 10.1007/s11465-021-0643-5
关键词: surface topography fractal evaluation fractal interpolation reconstruction composite
Xiaobin JIANG, Baohong HOU, Yongli WANG, Jingkang WANG
《化学科学与工程前沿(英文)》 2011年 第5卷 第4期 页码 435-441 doi: 10.1007/s11705-011-1139-3
关键词: melt crystallization porous media fractal permeability hyperpure material simulation
Optimal slot dimension for skirt support structure of coke drums
Edward WANG, Zihui XIA
《机械工程前沿(英文)》 2018年 第13卷 第4期 页码 554-562 doi: 10.1007/s11465-018-0513-y
The skirt-to-shell junction weld on coke drums is susceptible to fatigue failure due to severe thermal cyclic stresses. One method to decrease junction stress is to add slots near the top of the skirt, thereby reducing the local stiffness close to the weld. The most common skirt slot design is thin relative to its circumferential spacing. A new slot design, which is significantly wider, is proposed. In this study, thermal-mechanical elastoplastic 3-D finite element models of coke drums are created to analyze the effect of different skirt designs on the stress/strain field near the shell-to-skirt junction weld, as well as any other critical stress locations in the overall skirt design. The results confirm that the inclusion of the conventional slot design effectively reduces stress in the junction weld. However, it has also been found that the critical stress location migrates from the shell-to-skirt junction weld to the slot ends. A method is used to estimate the fatigue life near the critical areas of each skirt slot design. It is found that wider skirt slots provide a significant improvement on fatigue life in the weld and slot area.
关键词: coke drum stress analysis cyclic stress fatigue life skirt slots
Application of fractal theory to unsaturated soil mechanics
XU Yongfu, TONG Lixin
《结构与土木工程前沿(英文)》 2007年 第1卷 第4期 页码 411-421 doi: 10.1007/s11709-007-0056-5
关键词: selection soil-water independent physical unsaturated strength
潘玉良,吴立群,张云电
《中国工程科学》 2004年 第6卷 第5期 页码 49-51
介绍了W-M分形模型参数(D,G,γ)的物理含义,研究了分形参数(D,G,γ)与粗糙度参数Ra之间的联系,导出了分形参数(D,G,γ)与粗糙度参数Ra关系式,用数值分析拟合方法验证了关系式的正确性。
Immunometabolism: a new dimension in immunotherapy resistance
《医学前沿(英文)》 2023年 第17卷 第4期 页码 585-616 doi: 10.1007/s11684-023-1012-z
关键词: immune cell immunometabolism metabolic reprogramming immunotherapy resistance tumor microenvironment immune checkpoint inhibitor
王秀妮,姜威,王利村
《中国工程科学》 2006年 第8卷 第1期 页码 54-57
由于分形图像编码过程非常费时,因此在前人的基础上,通过分析影响分形图像编码速度的相关因素,提出了使用图像块的改进方差来提高分形压缩性能的思想。在证明迭代函数系统不会改变图像块的改进方差的基础上,给出了基于改进方差的分形图像压缩方法。实验结果说明该方法在保证快速性的同时,重建图像的质量又得到了进一步的提高。
Diagnosis method based on wavelet coefficient scale relativity correlation dimension for fault
GU Junjie, TIAN Jin, PENG Xuezhi
《能源前沿(英文)》 2008年 第2卷 第2期 页码 164-168 doi: 10.1007/s11708-008-0031-4
关键词: effective technology monitoring mechanical equipment relativity Correlation
标题 作者 时间 类型 操作
PD pattern recognition based on multi-fractal dimension in GIS
ZHANG Xiaoxing, YAO Yao, TANG Ju, ZHOU Qian, XU Zhongrong
期刊论文
Aggregating structure in coal water slurry studied by eDLVO theory and fractal dimension
Qiang LI, Qian WANG, Jian HOU, Jiansheng ZHANG, Yang ZHANG
期刊论文
Theoretical study on the confine-stiffening effect and fractal cracking of square concrete filled steel
期刊论文
Copper fractal growth during recycling from waste printed circuit boards by slurry electrolysis
期刊论文
Fractal characteristic evaluation and interpolation reconstruction for surface topography of drilled
期刊论文
Permeability analysis and seepage process study on crystal layer in melt crystallization with fractal
Xiaobin JIANG, Baohong HOU, Yongli WANG, Jingkang WANG
期刊论文