Results 71 to 80 of about 13,853 (179)
Study on correlation between coal spontaneous combustion characteristic temperature and physical and chemical characteristic parameters [PDF]
The fine division of coal spontaneous combustion characteristic stage is the premise for the establishment of early warning system of coal fire disaster.
Binbin ZHANG +6 more
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Politics &Policy, Volume 52, Issue 4, Page 801-827, August 2024.Abstract Political competition accelerates the enactment of lesbian, gay, bisexual, trans*, and intersexual rights (LGBTI+) due to the dynamic, rational behavior of mainstream parties across the political aisle to adapt to the sociopolitical environment.
Joel Cantó, Javier Arregui
wiley +1 more source
Gaoya dianqi, 2017 绝缘子泄漏电流能够综合体现绝缘子电压水平、污秽状态,贯穿于绝缘子的整个闪络发展过程,提取绝缘子泄漏电流特征量对预测绝缘子闪络事故的发生尤为重要。在人工污秽试验的基础上,利用分形理论提取了复合绝缘子泄漏电流分形维数特征量,分析了闪络发展过程中泄漏电流不同区段波形和分形维数的变化特征,对比了3种不同污秽度水平下泄漏电流波形的分形特征。结果表明,在污闪发展过程中,泄漏电流波形的分形维数呈整体下降的趋势;污秽程度不同,泄漏电流波形分形特征存在微小的差异。实验分析证明,泄漏电流波形分形维数能够直接反映其波形特征 ...
秦莉娟 +5 more
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滨海社区空间演变分形研究——以厦门市高浦社区为例 [PDF]
, 2019 滨海城市社区的空间形态及其海岸线表现出一定程度的复杂性,发展量化描述方法对于其可发展研究有重要的理论与应用价值。本研究基于分形理论,以滨海城市厦门的高浦社区为研究对象,利用计盒法对该滨海社区空间形态和边界进行复杂性分析和分形维计算,研究社区空间形态复杂性演变规律。结果表明:作为典型海湾渔村的高浦社区空间形态具有分数维,呈现分形结构特性。自1989年至今,该社区空间形态的分形维数呈现增长态势;社区边界的分形维数呈现下降态势。社区空间形态的分形维数与社区建筑占地面积、建筑总面积、建筑密度 ...
俞晓牮, 李焱龙, 林松, 赵志庆
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Integrative Conservation, Volume 3, Issue 2, Page 142-147, June 2024.In the process of integrating and optimizing of nature reserves in China, preserving farmland would increase the exposure level and decrease the maximum depth of nature reserves. Abstract Spatial contradictions between nature conservation and social development are prominent in the integration and optimization of nature reserves (NRs) in China.
Haiyang Gao, Di Zhu
wiley +1 more source
Zhejiang Daxue xuebao. Lixue ban, 2017 根据几何代数在地理空间对象建模和多维数据分析应用的特点，研究了共形几何代数交/并(meet/join)算子的含义、构建和应用.利用几何代数多维统一、高维计算适应的优势，设计了基于几何代数meet算子和有向半空间划分理论的时空宗地meet算法.从三维地籍和时空数据建模出发，在共形几何代数和时空代数范畴中，给出了三维、四维时空宗地的定义和表达.同时，以宗地数据的拓扑计算为例，将该算法运用于三维时空宗地拓扑计算场景——历史回溯中，取得了良好的效果.该算法的理念同样适用于四维时空宗地的历史回溯meet求解.
WANGQiaoyan(王巧燕) +4 more
doaj +1 more source
Influence of loading and unloading effect on mechanical properties of impact rock under impact load [PDF]
In order to study the effect of basic roof period pressure on the dynamic characteristics of impact pillar, one-dimensional dynamic and static combined loading SHPB experimental device is used to carry out dynamic impact experiment on the impact ...
Banquan ZENG +2 more
core +1 more source
Shuitu Baochi Xuebao, 2002 根系结构不同 ,其固持土体的能力存在很大差异。利用分形理论对不同根系结构稳定土体的能力进行了量化比较 ,结果表明 :(1)长江上游暗针叶林生态系统中主要树种根系都表现出了较为明显的分形结构特征 ,高山柳(Salix sp.)的根系结构最复杂 ,具有多层次细微分枝结构 ,分形维数最大 ,达 1.73 5 6 75 ,冬瓜杨 (Populuspurdomii)次之 ,为 1.6 0 16 6 ,峨眉冷杉 (Abiesf abri)分枝结构简单 ,以侧行主根为主 ,分形维数仅为 1.4 4 93 8 ...
谢春华 罗辑 等
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Characteristics of electric field strengthening between coal-mineral particles under microwave irradiation [PDF]
Both thermal and non-thermal effects induced by microwave radiation can produce a series of effects on coal and rock, and microwave induced discharge is one of the phenomena of microwave non-thermal effects.
Fuqiang YANG +5 more
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Shuitu Baochi Xuebao, 2008 以中亚带常绿阔叶林和杉木林为对照,对闽北典型竹林土壤微团聚体分形维数变化特征及其与土壤物理性质、化学性质、土壤酶活性及微生物数量的关系进行了研究,结果表明:>0.25 mm和0.05~0.01 mm颗粒含量越高,0.25~0.05 mm,0.005~0.001 ...
ZHANG Chang-shun +2 more
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