Results 11 to 20 of about 15,379 (117)
Zhejiang Daxue xuebao. Lixue ban, 2022 准噶尔盆地东北缘卡拉麦里地区是我国重要的金矿分布区，区内断裂系统错综复杂，控矿作用显著，需对不同方位、不同规模断裂系统的空间分布规律、发育复杂程度及对金矿床的控制规律进行深入研究，目前尚未见对该区域断裂系统的分形特征与金矿分布关系研究。对准噶尔盆地东北缘卡拉麦里地区断裂构造进行了不同尺度、不同方位的分形维数计算，得到全部断裂构造的分形维数为1.421，各方向断裂构造的分形维数：NW向为1.382，NWW向为1.223，近EW向为0.976，NE向为0.960 ...
SUNWenjie(孙文洁) +3 more
doaj +1 more source
Zhejiang Daxue xuebao. Lixue ban, 2017 分形维数是壳聚糖絮凝中药水提液絮体的重要参数，采用图像法测定絮体的分形维数，并应用Zeta电位仪测定了絮凝体系的ζ电位，对絮凝机理和絮凝效果进行了研究.选用壳聚糖作为絮凝剂，对白芍水提液进行净化除杂，通过改变絮凝剂投加量、絮凝温度、絮凝pH值等操作条件，探究这些因素对絮凝效果的影响，分析不同条件下絮体分形维数的变化规律：随着絮凝剂投加量的增加，絮体分形维数呈下降趋势；絮体分形维数随温度或pH值的升高出现先增大后降低的情况.通过正交实验确定白芍水提液的最佳工艺条件为絮凝剂投加量0.310 g • L-1 ...
ZHANGJianwei(张建伟) +3 more
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Computer simulation for fractal aggregates on nonlattice substrates(无格点基底表面分形凝聚体的计算机模拟)
Zhejiang Daxue xuebao. Lixue ban, 2000 对具有周期性边界条件的无格点正方形基底表面分形凝聚体的形成进行了计算机模拟。凝聚体由二种大小不同的圆盘组成。结果表明，凝聚体的分形维数几乎与表面覆盖率成正比，其斜率随圆盘的平均直径的增大而减小。当表面覆盖率很小时，分形维数几乎与圆盘的平均直径无关，约为1.45；当表面覆盖率较大时，分形维数随圆盘的平均直径的增大而减小。
XIAA-gen(夏阿根) +3 more
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Zhejiang Daxue xuebao. Lixue ban, 2023 以研究二维自治g-Navier-Stokes方程解的全局渐近性为目的，用算子分解方法证明了在有界区域上含非线性阻尼的二维自治g-Navier-Stokes方程解的双全局吸引子存在性，并估计了其Hausdorff 维数和Fractal维数。结果表明，该方程解的双全局吸引子存在且具有有限的Hausdorff 维数和有限的分形维数。
王小霞(WANG Xiaoxia) +2 more
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Zhejiang Daxue xuebao. Lixue ban, 2005 计算一类Sierpinski地毯的Hausdorff测度，利用投影降低分形维数及分形的分细分析方法，得到了这一类Sierpinski地毯的Hausdorff测度准确值.当这类Sierpinski地毯的Hausdorff维数s ∈ [log54，1]时，有Hausdorff测度准确值为Hs(S) = 1.
HEQin-bin(贺勤斌)
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Intangible drivers of tolerance shape human–elephant coexistence in Southwest China
People and Nature, EarlyView.Abstract Southwest China is home to a small but rapidly expanding population of Asian elephants (Elephas maximus), whose growth has intensified conflicts with people living in shared landscapes. These conflicts result in substantial economic losses and occasional human casualties. This coexistence paradox—where conservation success leads to significant
Xiaoyu Yu +4 more
wiley +1 more source
Zhejiang Daxue xuebao. Lixue ban, 2008 在扩散限制凝聚(DLA)模型基础上，采用Monte Carlo方法模拟了具有幂次相互作用的磁性粒子动力学凝聚过程.重点研究了在不同幂指数α值下团簇的形貌及其分形维数Df随耦合参数βC的演化规律.模拟结果表明：对于较大的α值，即α=5时，团簇形貌随βC的变化较小，其分形维数Df 一般在1.60~1.70；而随着α值的减小，团簇形貌随参数βC有一明显的演化过程，在模拟范围内，分形维数Df在1.20~1.95.
WANGFeng-fei(王凤飞) +2 more
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Uncovering correlates of decline and critical refuges for a threatened terrestrial mammal
Conservation Biology, EarlyView.Abstract Globally, the geographic ranges of numerous species are contracting. Identifying spatiotemporal patterns of threat impact can illuminate why species decline in some parts of their range but persist in others. We developed a correlative approach to identify species’ response thresholds and locate ecological refuge areas associated with ...
Natalya M. Maitz +5 more
wiley +1 more source
Policy Studies Journal, Volume 54, Issue 3, August 2026.ABSTRACT Despite extensive research on policy diffusion, the ways in which policy attention influences this process remain underexplored. This study addressed this gap by distinguishing between three types of policy attention—political speeches, policy issuance and field visits—and investigating their differential impacts when delivered by central and ...
Xiangning Chen, Yahua Wang
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Journal of Animal Ecology, Volume 95, Issue 7, Page 1178-1193, July 2026.This population‐comparative study reveals that male and female parents respond differently to social and ecological conditions. This sex‐specific responsive strategy is related to the incongruent parental care systems across populations in Chinese penduline tits.
Jia Zheng +5 more
wiley +1 more source