Results 31 to 40 of about 1,579,839 (226)
应用”逆向限制取样”的蒙特卡洛法,在考虑链团相互作用条件下,我们对线性链分子扭转态的构型相关特性进行了三维模拟。给出了在不同温度下,不同链长的链分子的单、双重及三重构型相关特性,并与用Flory类似于一维Ising模型的矩阵法处理结果做了比较 ...
孙祉伟
core +2 more sources
Taxonomic and functional diversity of urban bees of the world
Abstract Bees play a pivotal role in terrestrial environments. Urbanization can affect these organisms and the ecosystem services they provide. However, knowledge of the global diversity of urban bees is limited. Thus, we summarized data on urban bee species identities and occurrences; compared distributions of all bees with those found in urban ...
João C. F. Cardoso +10 more
wiley +1 more source
为了模拟计算ZnO电阻片在避雷器组限制过电压过程中吸收的能量,笔者针对所选取的电阻片进行冲击电流试验;绘制了在不同电流波形下的静态伏安特性曲线,描述了其与电阻片实际伏安特性的关系,并统计了同批次电阻片伏安特性分布规律;通过曲线拟合的方式建立伏安特性方程进行吸收能量的模拟计算。结果显示,在耐受冲击电流的过程中,电流波形波头时间对电阻片吸收能量计算等效性影响最大,波头时间越长,电阻片所表现出的伏安特性越接近试验绘制的静态伏安特性曲线,即通过静态伏安特性曲线进行能量模拟计算等效性越好。
刘志远 +6 more
doaj
鳜鱼视觉特性及其对捕食习性适应的研究II.视网膜结构特性梁旭方(中国科学院水生生物研究所,武汉430072)VISUALCHARACTERISTICSOFMANDARINFISH(SINIPERCACHUATSI)INRELATIONTOITSFEE..
梁旭方
core
Emerging applications of large language models in ecology and conservation science
Abstract Large language models (LLMs) mark a major development in artificial intelligence, with potentially transformative implications for ecology and conservation science. Built on advanced deep‐learning architectures, these models can support a wide range of tasks. We reviewed emerging applications of LLMs, drawing on the wider scientific literature
Christos Mammides +5 more
wiley +1 more source
针对在设计真空断路器弹簧操动机构凸轮轮廓线的过程中,依靠经验或者反复试验的方法设计出的凸轮轮廓线存在无法准确匹配负载特性的缺陷,采用一种负反馈优化设计方法。首先,根据负载特性推导出动力特性;其次,通过动力特性倒推出凸轮转角,进而计算出凸轮轮廓线;然后,根据凸轮呈现的合闸动力特性再次验证并修正负载特性,保证分合闸速度;最终,通过设计验证证明了使用该方法设计的凸轮能够使得动力特性准确匹配负载特性,并保证断路器可靠合闸。
赵玉芝 +5 more
doaj
采用基于半相对坐标系的操纵性计算方法对航行体回转特性进行了计算,通过量纲分析对主要影响参数进行分析,并将操纵性导数与常规潜艇进行了比较,分析新型航行体的操纵特性。采用隐式求解的VOF方法对新型航行体水面兴波特性进行研究,得到了航行体水面兴波特性的变化规律,可为同类型航行体水动力计算提供一定的参考。本文中翼身融合航行体可实现水下水面两种工作状态的切换,水下工作时其水平回转操纵性与垂直回转特性较传统潜艇相比具有明显差异,其垂直面回转操纵特性要明显优于水平面回转。此外,航行体水面运行条件下的傅汝德范围为0 ...
王一伟 +6 more
core
Institutional lessons from the Nordic management model
Abstract To improve wildlife management outcomes, in terms of reaching management goals and increasing legitimacy, Nordic countries have developed institutional systems involving stakeholders that aim for a more inclusive and participatory model.
Jens Nilsson +2 more
wiley +1 more source
介绍了晋东南-南阳-荆门1000kV交流试验示范工程中线路用盘形悬式瓷、玻璃和复合绝缘子的使用情况。分析研究了特高压绝缘子运行的积污、电气、机械和劣化等性能方面的情况,认为:应加强对特高压绝缘子积污特性、绝缘子直径对雨闪特性的影响,串形对绝缘子的机械特性影响,绝缘子运行的可靠性和劣化特性及机械振动特性的研究。建议待建特高压工程支柱绝缘子采用双柱并列式或三角锥式;及时开展盘形悬式瓷绝缘子劣化率、复合绝缘子憎水性和机械特性及钢脚腐蚀检测等工作 ...
吴光亚, 张予, 刘建坤, 张锐
doaj
Abstract Reversing ongoing biodiversity loss requires effectively managing anthropogenic threats. Although conservation actions can mitigate these threats, prioritizing and targeting such actions remain challenging because species respond differently depending on the nature of the threats and their biological traits.
Camila Guerrero‐Pineda +3 more
wiley +1 more source

