Results 41 to 50 of about 238,625 (167)
四川大学学报. 自然科学版, 1990 线性模型yi=x′iθ+ei,i=1…n,的误差序列{ei}in=1有未知密度f（x）,本文在一定条件下证明了f（x）的核估计的弱相合性,逐点强相合性,一致强相合性,其中（?）为L.S估计的残差.
张文扬
doaj
Study on the inference method of logistics costs(物流成本的推断方法研究)
Zhejiang Daxue xuebao. Lixue ban, 2011 原本方物流成本和第三方物流成本会因各自条件明显欠缺而难以集中并进行会计核算.尽管如此，却可以运用统计方法对它们进行估算，即在理清物流成本结构的基础上，分别对物流需求者和物流经营者总体的有关特征进行抽样推断，进而估算出原本方物流成本和第三方物流成本以及由它们合成的物流供给成本.抽样推断方法具有科学性和可操作性，能有效解决物流成本估算问题，其应用成果为制定物流发展规划或设计物流建设方案提供了依据，为解决物流卫星账户构建之瓶颈问题奠定了重要基础.
GUOQing-guang(郭庆广)
doaj +1 more source
A Multidimensional Operationalization of Policy Change
Politics &Policy, Volume 53, Issue 5, October 2025.ABSTRACT Policy change is a core variable of policy process research. Several theories and frameworks distinguish different levels of policy change. These include minor change vs. major change (Advocacy Coalition Framework), incrementalism vs. nonincrementalism (Multiple Streams Framework), punctuations vs.
Nils C. Bandelow +2 more
wiley +1 more source
XpertMtb/RIF技术对结核病以及耐药结核病的诊断应用价值
Zhongguo shiyan zhenduanxue, 2018 据WHO统计,我国是全球22个结核病流行严重的高负担国家之一,结核病患病人数高居全球第2位,同时也是全球27个耐多药结核病流行严重的高负担国家之一,耐多药结核病患者的估计人数高居全球第1位[1]。而传统的诊断标准是抗酸杆菌染色法和结核分枝杆菌培养药敏法,抗酸染色法敏感度较差,阳性率低 ...
张永强 +5 more
doaj
Integrative Conservation, Volume 4, Issue 3, Page 405-415, September 2025.Assessing the genetic diversity of edible insects harvested from the wild is a pre‐requisite for designing conservation and management policies. The caterpillars of Gynanisa maja (Saturniidae) are harvested in large numbers in mopane woodlands in southern Africa, where they represent a seasonal source of income and nutrition to many rural communities ...
Zwannda Nethavhani +3 more
wiley +1 more source
Accurate kernel estimation for blind deblurring of noisy and blurred images
, 2016 针对大多数先进的单幅图像盲目反降晰技术在噪声无法忽略时,仍不能很好地处理模糊核估计质量退化严重的问题,提出一种利用图像显著结构从单幅噪声模糊图像中准确估计模糊核的方法。首先通过降噪预处理对图像噪声进行抑制,利用基于全总变分模型的方法提取模糊图像的显著结构,进而运用梯度选择方法移除不利于模糊核估计的显著边缘,提高模糊核估计的鲁棒性;然后采取两阶段模糊核估计策略,运用基于图像显著结构模糊核估计方法和迭代支持域检测技术实现模糊核的准确估计;最后通过稀疏先验约束的非盲目图像解卷积方法完成最终的图像恢复 ...
郝明国, 赵怀慈, 李波, 孙士洁
core
四川大学学报. 自然科学版, 2006 数字视频中的动态目标分割是基于计算机视觉技术的分析、识别系统中关键的处理步骤,分割结果的正确率决定了后期分析或识别过程的质量.在数字视频中存在各种有害动态像素,它们会降低分割过程的正确率.动态目标的阴影是这些有害像素的一种,因为它们本身不属于动态目标形状信息的范畴,但分割过程却能很容易将它们作为有效的动态目标像素分割出来.最近有关动态目标分割的研究提出了基于核心密度估计模型的分割方法.基于RGB颜色空间的核心密度估计模型能够在彩色视频中抑制阴影,但是对于灰度视频这种模型是无法抑制阴影的 ...
李征, 杨舰, 琚生根, 张胜
doaj
Integrative Conservation, Volume 4, Issue 3, Page 302-309, September 2025.We discussed the key assumptions of Distance sampling that were considered hard to meet in mountainous terrains and potential solutions for them. Our survey yielded comparable estimates from distance sampling and double‐observer survey, although the confidence interval from distance sampling was broader.
Lingyun Xiao +4 more
wiley +1 more source
Risk, Hazards &Crisis in Public Policy, Volume 16, Issue 3, September 2025.ABSTRACT The study investigated relations between psychological capital (PsyCap), personal well‐being, and feelings of stress and anxiety among evacuees from northern Israel during the Iron Swords war, examining differences between employed and non‐employed evacuees. A sample of 126 participants was divided into two subsamples: employed and unemployed.
Batel Hazan‐Liran, Nirit Karni‐Vizer
wiley +1 more source