Results 21 to 30 of about 4,127 (127)
Zhejiang Daxue xuebao. Lixue ban, 2009 提出了一种求解非齐次各向异性热传导方程一类反问题IHCP(inverse heat conduction problem）的无网格方法,该方法通过借助基于测地距离的Multiquadric(MQ）作为基函数得到整个时间空间区域上的一个近似特解,然后用基于测地距离的基本解方法直接在整个时间空间区域上对相应的齐次问题进行求解.用截断奇异值分解(TSVD)法求解所得病态线性方程组,用L-曲线准则确定正则化参数.用数值例子验证了该方法的有效性,并分析了数值解的精度与参数T、c的关系.
WANGJin-yu(王金玉) +1 more
doaj +1 more source
Image retargeting through fusion of contour and region information [PDF]
, 2012 图像显示适应面临展示面积受限、长宽比不固定等问题,已经成为多媒体领域的研究热点之一。关键是收缩后能够凸显图像重要区域,保持连续,避免扭曲。提出了一种基于区域轮廓能量的图像显示适应算法,通过对图像的视觉显著度分析,得到符合人类视觉的图像区域轮廓能量分布图。这样,在缩放过程中,删除或复制表示非敏感内容的低能量线,并且在显示图像内容的同时突出图像中的显著区域。实验结果表明,该方法保持了图像中显著目标的原始比例,具有很好的抗畸变性能。Image retargeting techniques aim to ...
杜晓凤, 陈诚, 马金素
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World Water Policy, Volume 12, Issue 1, February 2026.ABSTRACT Urban expansion significantly impacts flood risk, particularly in rapidly growing areas where impervious surfaces exacerbate surface runoff. This study examines spatial patterns of urban growth and their effects on flood exposure in Mecklenburg County, North Carolina, from 2011 to 2021.
Pegah Madadi, Azad Sadeghi
wiley +1 more source
World Medical &Health Policy, Volume 17, Issue 4, Page 823-830, December 2025.ABSTRACT Sepsis is a leading cause of mortality in the United States, with over 350,000 deaths annually, yet the contribution of neighborhood‐level social determinants of health (SDoH) remains underexplored. We conducted a retrospective analysis of 4.4 million hospitalized patients with sepsis, identified using ICD‐10 codes, leveraging de‐identified ...
Ahad Khaleghi Ardabili +3 more
wiley +1 more source
Gaoya dianqi, 2019 深井接地极因占地面积小,选址容易的优点,具有很高的工程实用价值。由于单根深井接地极最大对角线距离不到1 m,明显不宜直接采用规程推荐的5倍对角线距离人工布线测量接地电阻。为此,文中建立了直流深井接地极模型,仿真计算了其接地电阻和地表电位分布,基于之提出了电流极距离要求;建立了深井接地极注流、电流极回流的模型,研究了接地电阻测量过程中深井接地极和电流极共同作用下的地表电位分布规律;结合深井接地极接地电阻的仿真计算值,分析获得了电压极的布置要求。改变电流极和电压极的位置,研究了测量误差与布线距离之间的关系 ...
陈家峰 +6 more
doaj
Adaptive Knot Placement in Non-uniform B-spline Surface Fitting [PDF]
, 2015 针对非均匀b样条的节点设置问题,提出一种利用非均匀b样条曲面拟合离散数据的迭代算法,通过优化节点分布来改进拟合曲面的质量.该算法以带参数化的三角网格曲面为输入,在首次迭代中根据输入曲面的几何特征将其对应的参数域划分成若干个子区域,并使得每个子区域上累积的几何特征信息量近似相等,子区域的重心坐标将取为首次迭代的节点;在随后的迭代中,保证前次迭代生成的重心位置固定不变,并根据前次迭代得到的曲面拟合误差再次将区域划分成累积误差接近相等的子区域,新增加的子区域重心的坐标选为拟加入的节点 ...
曹娟 +3 more
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Conservation Biology, Volume 39, Issue 6, December 2025.Abstract Identifying refugia from emerging threats is vital to ensure the persistence of rare and threatened species, but modeling habitat distribution for these species is challenging and the role of people in refuge management is rarely considered. Myrtle rust is an emerging infectious disease that represents a grave threat to the rare wetland tree ...
Sarah M. Herbert +7 more
wiley +1 more source
Importance of connectivity for carnivore richness and occupancy in fragmented biodiversity hotspots
Conservation Biology, Volume 39, Issue 6, December 2025.Abstract Structural connectivity affects wildlife movement between habitat patches, contributing to the persistence of wildlife populations and their resilience to human‐induced and environmental changes. However, its importance to wildlife population persistence remains unclear, particularly in fragmented landscapes, where there are additional co ...
Cindy M. Hurtado +12 more
wiley +1 more source
野生动物学报, 2011 2009年3月,采用样线法、样点法对辽宁双台河口自然保护区内迁徙停歇的丹顶鹤进行观察监测,确认并用GPS定位其停歇地;通过样方法、因子测定法进行对其停歇生境进行实地测量与分析。结果表明:（1）芦苇沼泽是丹顶鹤主选的停歇生境,占到96.4%;（2）丹顶鹤停歇地与火烧地的距离小于25 m,在火烧地边缘活动,或者停在火烧地中;（3）丹顶鹤一般会选择油井距离大于1 km处作为停歇地（100%）;（4）丹顶鹤距明水面的距离较近,便于获取食物与水等;（5）频繁区对丹顶鹤影响明显 ...
金洪阳, 郝萌, 杨玉成, 邹红菲
doaj
Gaoya dianqi, 2020 频率响应分析法是检测电力变压器绕组变形的常用诊断方法之一。近年来,频率响应分析法的检测流程趋向标准化,但寻求合适的算法对频响曲线数据进行量化分析仍需深入研究。文中将频响曲线数据的量化分析看作一个概率分类问题,提出了应用欧氏距离分析诊断变压器绕组变形程度和类型的新方法。研究结果表明,欧氏距离分析能够有效地对变压器绕组变形程度进行诊断,且与先前研究提出的数学指数方法相比,该方法对变形程度的诊断结果具有更高的线性度。同时,在检测频段分段后获取子频段的欧氏距离分布的基础上 ...
张重远 +6 more
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