Results 11 to 20 of about 8,580 (118)
四川大学学报. 自然科学版, 1996 对于线性模型，误差序列，有未知密度函数ｆ（ｘ）．在对核ｋ（·）及Ｍ－估计中的ρ（·）施加非常弱的条件下，证明了ｆ（Ｘ）的核估计的弱相合、强相合和一致强相合性．其中：为β的Ｍ－估计．
张文扬, 施笋娟
doaj
Microstructure Engineering Toward High Cost‐Effective Nd–Fe–B Sintered Magnets: A Review
Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT Nd–Fe–B sintered magnets, critical for enhancing electromechanical conversion efficiency and operational stability in wind turbines and electric vehicle drives, are prized for their outstanding coercivity, high remanence, and superior maximum energy product.
Dongmin Zhang +5 more
wiley +1 more source
四川大学学报. 自然科学版, 2012 在经典的核心密度估计模型中,基于像素亮度的估计能够将同一目标更好地连通显示,具有集中的像素分布规律.利用这一规律,可将经典核密度模型的计算维度扩展到二维,用其分割像素对应的光流场,并称该方法为基于光流场核密度估计的动态目标分割模型.实验证明,该方法能够从运动背景中很好地检测出较完整的运动目标.
王洋, 李征, 孙嘉
doaj
Does the Community Understand the Community Guidelines?
Policy &Internet, Volume 18, Issue 2, June 2026.ABSTRACT Amid continued public controversy and political debate about online speech governments and civil society have pushed social media platforms to increase transparency around how they regulate speech, through community guidelines and content moderation systems, to support users to hold companies accountable for content removals.
Friederike Quint +4 more
wiley +1 more source
四川大学学报. 自然科学版, 2010 在多传感器决策和估计融合中,利用多站之间的随机信号观测的联合密度函数可以提高决策和估计融合的性能.然而,在多传感器信号的观测采样过程中,单站往往可以采到丰富的信号观测样本,而多站之间只能采集到少量的联合信号观测样本.采用经典的核密度估计方法只能利用多站之间少量的联合随机信号的观测样本来估计信号观测的联合密度函数,无法利用单站丰富的信号观测的样本信息.本文基于Copulas获得了两种多元密度函数的非参数估计方法.它们既能充分的利用多站之间的少量的联合观测样本的信息,又能充分的利用单站丰富的观测样本的信息 ...
代增, 沈晓静, 朱允民
doaj
He jishu海洋核动力小堆作为未来海洋核能应用的重要形式，其热工水力特性受到周期性流体波动和复杂运动的影响，增加了设计与安全评估的挑战。本研究旨在开发一种多尺度分析方法，通过适应性改造和多层次模拟，系统评估海洋条件下核动力小堆的热工水力行为与安全性。首先，选用STAR-CCM+作为改造系统分析、子通道和计算流体力学（Computational Fluid Dynamics，CFD）等程序的工具，对RELAP5源程序进行了修改，对海洋小堆进行简化建模，以适应海洋环境下的系统行为、组件传热、燃料棒束等关键特性；其次 ...
罗 涵禹, 宋 厚德, 刘 晓晶
doaj +1 more source
Biodiversity‐driven spatial conservation planning to delineate temporally stable regions
Conservation Biology, Volume 40, Issue 3, June 2026.Abstract The accelerating loss of biodiversity underscores the critical need for effective conservation strategies, particularly in the face of climate change and anthropogenic pressures. We devised a conservation planning framework that adopts a temporal stacking approach to species distribution models and landscape connectivity analyses. These models
Mattia Iannella +5 more
wiley +1 more source
Aspect Ratio‐Controlled Chiral Nanostructures for Dual‐Mode Breast Cancer Theranostics
Rare Metals, Volume 45, Issue 5, May 2026.ABSTRACT Chiral CdSe/CdS quantum dots (QDs) have emerged as promising platforms for precise cancer diagnosis and therapy due to their unique optical properties and biological interactions. In this study, we systematically investigated the role of aspect ratio (AR) modulation in ultrathin‐shelled chiral CdSe/CdS dot‐in‐rods (DRs) on their performance in
Linxuan Wu +9 more
wiley +1 more source
四川大学学报. 自然科学版, 2007 在医学诊断检测中,对于连续的检测结果,通常用ROC曲线来测量其准确性.作者研究了常用的ROC曲线的非参数估计,并给出一种新的核光滑估计方法.使用这种新方法,不但可以减少均方误差,而且只需用一个窗宽来估计,克服了Lloyd方法的缺点.
周永道, 宋捷, 赵永红
doaj
How much biotic nativeness matters across human demographic groups
Conservation Biology, Volume 40, Issue 2, April 2026.Abstract Many central concepts of conservation biology—such as nativeness—are structured by ecological and social factors. However, the social consequences of using these concepts to make conservation decisions remain inadequately understood. Some researchers argue that nativeness, rather than acting as an objective proxy for important ecological ...
Harold N. Eyster, Rachelle K. Gould
wiley +1 more source