Results 41 to 50 of about 106,323 (223)
Using porous metals to enhance heat transfer in phase change materials (PCMs) [PDF]
Heat transfer enhancement mechanism of Phase Change Materials (PCMs) by high-porosity metal foams was investigated in this study. The Darcy-Brinkman-Forchheimer modified flow model was employed in the numerical simulations to consider the non-Darcy ...
Tian, Y. (Yuan), Zhao, Changying
core
Informing spatial conservation prioritization with species’ traits
Abstract New Guinea, the most botanically diverse island on the planet, is the location for one of the boldest conservation initiatives. The Manokwari Declaration aims to achieve 70% conservation designation for the Bird's Head Peninsula. This is 40% higher than the 2022 Global Biodiversity Framework target.
Liam A. Trethowan +27 more
wiley +1 more source
Greenhouse gas emissions from croplands of China [PDF]
China possesses cropland of 1.33 million km 2. Cultivation of the cropland not only altered the biogeochemical cycles of carbon (C) and nitrogen (N) in the agroecosystems but also affected global climate.
Bohan, Liao +13 more
core +1 more source
Comprehensive framework for assessing and optimizing existing research networks
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
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
暂态恢复电压(TRV)标准值参数是考核高压交流断路器在大容量试验站进行短路开断试验时的一项重要指标。文中提出了一种基于坐标系转换的TRV波形包络线与标准值参数计算方法,通过对TRV波形数据经过数学运算由笛卡尔坐标系转换到极坐标系下,进一步对极坐标系下的TRV波形数据计算可以得出与TRV波形相切的3条直线(两参数TRV)或4条包直线(四参数TRV)所组成的包络线以及TRV的标准值参数。应用该计算方法所获得TRV标准值参数,为大容量试验站进行短路开断试验时,预期TRV调试时试验回路R、L ...
班建, 高享想, 黄实, 李刚
doaj
以SMART-1台阵第45号地震的南北分量加速度作为研究对象,计算截止频率fcut分别为8,16和24 Hz,台站间距分别为200,1 000和2 000 m这9种工况的相干系数,并进行曲线拟合,再根据9组拟合参数计算相应的相干系数并进行比较。结果表明:① 截止频率fcut的取值对相干函数统计模型参数和相干系数拟合曲线有很大影响;② 根据较小的截止频率fcut得到的拟合参数计算出的相干系数随频率的衰减很快,反之,根据较大的截止频率fcut得到的拟合参数计算出的相干系数随频率的衰减较慢;③ ...
Haiping Ding, Yi Luo, Weibo Rao, Yue Zhu
doaj +1 more source
Restriction and Position Deposition of Electrohydrodynamic Direct-Writing Jet Beased on Weissenberg Effect [PDF]
电纺直写技术以其独特的原理性优势被认为是最具发展前景的微纳制造技术之一,提高射流的稳定性和有机微纳结构的沉积精度是将电纺直写技术应用到各领域的关键技术。本文利用溶液在微管道内的韦森堡效应实现对喷头供液,并围绕该供液方式对电纺直写泰勒锥、射流的稳定性和沉积行为展开研究,促进电纺直写的发展。 本文设计一种基于韦森堡效应的旋转针芯喷头,分析旋转针芯喷头的供液原理,并利用工业相机观测旋转供液方式的速度稳定性,考察针芯转动速度、液柱高度等工艺参数,以及微管道长度、针芯伸出长度、针芯柱径等结构参数对供液速度 ...
王伟
core
Evaluating the empirical basis for threat attribution in the IUCN Red List
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
对特殊参数的组合波发生器进行研究。首先讨论了波形参数、电路参数、电源利用率等之间的关系并得出有实用参考价值的曲线,根据此曲线,可以方便地确定特殊参数组合波在不同虚拟阻抗下的电路参数;其次,针对有代表性的电路(如10/1000电压波、10/1000电流波以及10/700电压波、10/300电流波等),选取一定虚拟阻抗下的电路参数,并进行仿真,验证了理论计算的正确性。
姚学玲, 陈景亮, 孙伟
doaj

