Results 21 to 30 of about 18,901 (182)
Gaoya dianqi, 2011 针对40.5kV新型磁力机构工作原理及其运动特点,进行了多场耦合的静态和动态特性仿真研究。首先,建立磁力操动机构的有限元模型,利用Maxwell软件对磁力机构的静态特性进行仿真;其次,根据电压平衡方程和达朗贝尔运动方程,在静态仿真基础上采用ADAMS和MATLAB建立40.5kV磁力机构SF6断路器运动模型,对磁力机构的动铁心、SF6断路器触头运动特性进行了仿真研究。最后,分析了磁力机构运动特性对SF6断路器性能的影响,为新型磁力机构在中压SF6断路器中应用提供了一定理论基础。
茹晶晶 +5 more
doaj
Representation of obligate groundwater‐dwelling copepod diversity in European protected areas
Conservation Biology, EarlyView.Abstract Groundwaters sustain diverse surface ecosystems and are populated by metazoan species, mostly invertebrates, that provide fundamental ecological functions and are often of prominent conservation value due to narrow endemism and high phylogenetic rarity.
Francesco Cerasoli +7 more
wiley +1 more source
Design and Implementation of Music Learning Community System for an University [PDF]
, 2015 随着互联网技术的迅猛发展，人与人之间的连接更加频繁。当前碎片化时间学习使得人们的知识获取或者技能学习受到了严重影响。网络学习社区逐渐成为人们日常工作和学习的必备工具。高等院校在线学习社区也逐渐发展起来。高校学校社区的参与者主要是学生、教师，其具有相对固定的联系，生活环境相似，并且都是教育教学活动的参与者。高校学习社区的目标就是知识的创造、传播，达到认知的目的。高校师生通常是有强烈知识渴求的人。信息技术和互联网的发展，信息的传播效率极高，成本很低。本文将以高校的音乐教学领域作为切入点 ...
黄鹏
core
Dianci bileiqi, 1988 在应用敲击法对高压电瓷动态弹性模量测试结果进行修正的基础上,探讨了高压电瓷动态弹性模量的分布。根据动态弹性模量服从复合型威布尔分布的特点提出一个由特定配方的动态弹性模量预测其强度的方法。在均值意义下,还给出了高压电瓷动态弹性模量和强度间的相关关系。应用这个相关关系,它们间的相互推断具有较高的精度。
马功勋
doaj
Conservation Biology, EarlyView.Abstract In the western United States, conservation practitioners are increasingly working with private landowners to restore habitat for North American beavers (Castor canadensis) and to use nonlethal mitigation techniques when beavers damage crops and infrastructure.
Brian D. Erickson, Megan S. Jones
wiley +1 more source
Effects of political identity activation and inaccurate metaperceptions on attitudes toward wolves
Conservation Biology, EarlyView.Abstract Polarization between groups can undermine durable conservation outcomes. Activating group identities (i.e., an individual's sense of self derived from membership in a group) can exacerbate differences, especially when people hold inaccurate perceptions of their peers and rivals.
Alexander L. Metcalf, Justin W. Angle
wiley +1 more source
Gaoya dianqi, 1997 根据理论模型和实验首先分析了真空开关触头在开断过程中的状态及其运动特性对开断能力的影响,然后描述了开关触头的关合特性。在此基础上,讨论并提出了理想的触头运动特性,在这一特性下能缩短平均燃弧时间,可望改善大电流开断后的触头表面状态。
王瑛, 蔡威, 邹积岩
doaj
Geographic risks to functional groups of mammals and birds from habitat loss in Mexico
Conservation Biology, EarlyView.Abstract There is a need to quantify the impact of habitat loss due to anthropogenic factors on different aspects of biodiversity, such as functional trait diversity represented by functional groups (FGs). We developed a metric to assess the weighted risk of loss of habitat for 33 FGs of mammals and 36 FGs of birds in Mexico based on potential ...
Fernando Mayani‐Parás +4 more
wiley +1 more source
Progress of dye-sensitized water-splitting for hydrogen production [PDF]
, 2006 The mechanism of dye-sensitized water-splitting for hydrogen production is introduced. Research works on the use of different dye molecules and redox mediators are reviewed.
Leung, MKH, Leung, YC, Ni, M
core
Harnessing social media data to track species range shifts
Conservation Biology, EarlyView.Abstract Biodiversity monitoring programs and citizen science data remain heavily biased toward the Global North. Especially in megadiverse countries with limited biodiversity records, incorporating social media data can help address existing data gaps.
Shawan Chowdhury +15 more
wiley +1 more source