Results 71 to 80 of about 69,960 (229)
Comprehensive framework for assessing and optimizing existing research networks
Conservation Biology, EarlyView.Abstract Conservation, monitoring, and research networks, or collections of ecological research sites unified under a common mission of data collection or a research mission, are essential infrastructure for understanding large landscapes. However, most networks developed opportunistically over decades rather than through systematic design, creating ...
Alyson East +2 more
wiley +1 more source
开放式伞形结构的形状和尺寸对爬电距离、形状因数和等效直径的影响
Dianci bileiqi, 2018 将开放式伞形结构细化为8项径向和3项轴向基本参数,给出了爬电距离、形状因数和等效直径的参数化表达式,并讨论了每一项参数对后三者的影响。采用数学建模的方法,将伞形优化设计问题转化为多元函数求最值的问题进行了讨论。本文的研究内容可为伞形优化设计提供参考。
李启源
doaj
基于蒙特卡洛算法的1100 kV变压器套管椭圆形双均压环参数优化设计
Dianci bileiqi, 2023 为了降低特高压变压器套管引线端的最大场强，避免局放产生的影响，对1 100 kV变压器套管引线端的双均压环进行优化设计。通过改变表面曲率可以调节均压环上的场强最大值，由此设计参数化椭圆形均压环，应用蒙特卡洛算法分别对椭圆形上、下均压环的参数b、参数c和旋转角度θ进行参数优化分析，得到了椭圆形上下均压环的最佳参数配置。优化结果表明，当椭圆形上均压环参数b=c=92 mm,θ=-60°,椭圆形下均压环参数b=c=85 mm,θ=-102°时，上下均压环的表面场强最大值分别下降了4.8%和6.4 ...
刘闯 +4 more
doaj
Conservation Biology, EarlyView.Abstract Recognition and engagement of Indigenous Peoples and local communities (IP&LCs) and other traditional knowledge (TK) holders in formal biodiversity governance remain limited, despite their significant contribution to the conservation and sustainable use of biodiversity through their knowledge, innovations, practices, and land stewardship.
Kinga Öllerer +8 more
wiley +1 more source
"中国区域地震学参考模型"成果中心 Level-II 数据库:远震 P 波偏振、短周期瑞利波椭率和浅部平均接收函数
, 2023 Xiao Xiao +6 more
openalex +1 more source
Standardization of Rational Bézier Surfaces [PDF]
, 2007 National audienceThe sufficient and necessary condition for the existence of linear Möbius transformations that can standardize the rational Bézier surfaces is given based on Möbius reparameterization theorem.
Yang, Yi-Jun, Yong, Jun-Hai
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Evaluating the empirical basis for threat attribution in the IUCN Red List
Conservation Biology, EarlyView.Abstract Understanding the impacts of different threats on species is key to successful conservation interventions and policies. The International Union for Conservation of Nature (IUCN) assesses threats to species, and the organization's Red List of Threatened Species is a key conservation tool.
Ena Humphries +5 more
wiley +1 more source
Gaoya dianqi, 2016 变压器油纸绝缘系统的介质响应特性可以用扩展德拜模型等值电路来描述,研究变压器油纸绝缘系统等值电路参数的辨识方法具有十分重要的意义。文中提出一种应用极化电流辨识变压器油纸绝缘系统扩展德拜等值电路参数的方法,利用极化电流曲线末端主要取决于大时间常数指数项的特点,先在曲线末端不为零处选取初始点计算得到大时间常数支路参数的估计值,再以估计值为基础进行多次修正计算,待参数计算值稳定后再进行检验计算,从而求得各个参数较为准确的数值解;逐条计算,可以求出所有极化支路的参数 ...
蔡锋, 江修波, 蔡金锭
doaj
Jixie chuandong, 2015 由于自动装盒机装盒尺寸不同,送盒凸轮大小和行程等参数都会改变,需经常更换送盒凸轮。传统的CAD/CAM软件凸轮设计既费时又困难,据此基于UG二次开发工具,结合VC++6.0开发了凸轮参数化系统软件。经运行表明,系统具有良好的人机交互性,用户只需要输入需要修改的关键参数就可以得到新的凸轮三维模型,缩短了设计时间,实现了凸轮参数化设计。为凸轮的数控加工、仿真设计与制造、参数化设计提供了参考依据。
张宪信, 郭烈恩, 王官明
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Parameter estimation in exponential failure rate model using masked data(失效率为指数函数的模型中使用屏蔽数据的参数估计)
Zhejiang Daxue xuebao. Lixue ban, 2006 考虑一个由独立、不完全相同的单元组成的串联系统，使用屏蔽数据时的参数估计.当失效率为指数函数时，给出了参数的极大似然估计和Bayes估计.在Bayes估计中，假定未知参数的先验分布为对称的三角分布.主要考虑两单元串联系统，并通过数据模拟对极大似然估计和Bayes估计这两种方法进行了比较.
JIANGHong-yan(姜红燕) +1 more
doaj +1 more source