Results 31 to 40 of about 14,817 (116)
Gaoya dianqi, 2001 本文将分形理论应用于局部放电模式识别 ,从统计图谱中提取分形特征。在局部放电模式试验基础上 ,采用计盒数的分形维数算法 ,从大量的局部放电样本中提取分形网格维数特征参数 ,提高了局部放电模式的准确性。
李剑 +4 more
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Chaotic phenomenons in observation series of water consumption(用水量时间观测序列中的分形和混沌特性)
Zhejiang Daxue xuebao. Lixue ban, 2004 探讨了城市不同用水量时间观测序列中的分形和混沌特性.对城市日用水量、时用水量及各日典型时段(9 时、2时）用水量观测序列按照关联维数求算吸引子维数.计算结果表明，不同城市用水量观测序列的吸引子维数均以分数形式存在，且各时段用水量序列分形维计算结果明显不同；相反，相同序列不同起始时刻的计算结果比较接近和稳定.研究初步表明用水量观测序列中除了通常认为的周期性、趋势性及随机扰动性成分以外，还存在有较为明显的混沌成分.以上结论的得出对用水量需求预测的方法研究和系统建模具有积极意义.
LIUJing-qing(柳景青)
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Ultrasound in Obstetrics &Gynecology, Volume 65, Issue 5, Page 624-632, May 2025.ABSTRACT Objectives Placental insufficiency contributes to many obstetric pathologies, but there is no bedside clinical tool to evaluate placental perfusion. We have developed a method to acquire multiple three‐dimensional (3D) power Doppler (PD) ultrasound (US) volumes of placental vasculature, with infrared camera tracking of the precise spatial ...
A. Xue +5 more
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China's Eco‐Civilisation, Climate Leviathan, and Hobbesian Energy Transition
Antipode, Volume 57, Issue 3, Page 830-861, May 2025.Abstract Scholars have hitherto tended to theorise China's ecological civilisation project either as a form of environmental authoritarianism or as a vision of eco‐socialism. This paper contributes to the conversation by conducting a textual analysis of Chinese scholarly discussions on eco‐civilisation.
David Chen
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Shuitu Baochi Xuebao, 2011 运用土壤粒径质量分布原理与分形理论,研究泥石流频发区蒋家沟3种不同盖度草地土壤粒径分形特征。结果表明:不同盖度草地的土壤粒径分布具有不同的分形特征,其分形维数在2.520 8～2.669 1之间,其关系为:低盖度草地>高盖度草地>中盖度草地 ...
谢贤健, 韦方强
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Compression and simplification of CRM type decomposition map(CRM分解图的压缩及其化简)
Zhejiang Daxue xuebao. Lixue ban, 2006 CRM分解图可以用来指导超大规模集成电路的设计和化简.本文在分析应用CRM分解图进行逻辑函数或-符合式化简的基础上提出了逻辑函数的降维CRM分解图，给出了降维CRM分解图的定义和图形化简方法.实例表明，该图形方法有直观、简单等特点，它能给出逻辑函数的最简或-符合式，使电路实现比传统设计更简单、更有效.
ZHAOMei-ling(赵美玲) +2 more
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Policy &Internet, Volume 16, Issue 4, Page 727-738, December 2024.ABSTRACT Digital sovereignty unfolds differently and unevenly across geographies. The paper describes and theorizes three models of state digital sovereignty from the Global South—China, India and South Africa—three BRICS member countries that are home to over 1/3 of the world's population.
Min Jiang
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Shuitu Baochi Xuebao, 2011 选取14个关中平原高速公路路堤边坡样地,分析了不同植被恢复年限下土壤水稳定性团聚体特征.结果表明:(1)随年限延长,＞1 mm大团聚体表层含量基本大于亚表层含量;＜1 mm团聚体则相反;＜0.25 mm微团聚体含量呈现出先增大后又减小的趋势,而＞5 mm团聚体含量则先减小后增大.(2)研究区阳面边坡分形维数为2.45～2.79,阴面边坡分形维数为2.48～2.70,变化幅度较小;表层分形维数小于亚表层.(3)分形维数与＜0.25 mm团聚体含量显著正相关,与有机质、全氮显著负相关.(4 ...
刘爱霞 +4 more
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The enigmatic life history of the bamboo explained as a strategy to arrest succession
Ecological Monographs, Volume 94, Issue 4, November 2024.Abstract Bamboos are perennial woody grasses that display an enigmatic mix of traits. Bamboo is highly shade intolerant like early‐successional trees. Without secondary xylem, bamboos cannot continue to grow once they reach a maximum height or replace xylem damaged by hydraulic stress and must instead replace each stem after a few years using ...
Aiyu Zheng, Stephen W. Pacala
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Ultrasound in Obstetrics &Gynecology, Volume 64, Issue 5, Page 661-668, November 2024.ABSTRACT Objective To determine the diagnostic accuracy of virtual autopsy using whole‐body postmortem ultra‐high field magnetic resonance imaging (MRI) at 7 Tesla (T), using a short T2‐weighted imaging (T2‐WI) protocol, compared with classical autopsy, for detecting structural abnormalities in small second‐trimester fetuses. Methods Thirty consecutive
A. Staicu +11 more
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