Results 11 to 20 of about 503,149 (148)

500kV直流断路器快速机械开关典型故障特性及可靠性提升方法研究 [PDF]

open access: yes, 2023
直流断路器是构建柔性直流电网不可或缺的关键设备。快速机械开关是直流断路器中承载电流、实现快速分合闸、耐受分闸恢复电压的核心组件,其结构复杂、动作速度快、电气应力严酷、可靠性要求高,因而设计研制难度大,任一环节出现问题均会影响直流断路器乃至柔直电网的安全可靠运行。然而,目前快速机械开关由于存在设计选型不合理、工艺管控不严格、试验考核不完善等问题,导致在实际工程应用中故障率较高。针对已应用于张北柔性直流电网试验示范工程的500 kV直流断路器,分析了直流断路器研制、调试 ...
张涛   +4 more
core   +2 more sources

Modelling past and future land‐use changes from mining, agriculture, industry and biodiversity in a rapidly developing Southeast Asian region 采矿、农业、工业和生物多样性保护影响下东南亚快速发展区域过去和未来土地利用变化模拟

open access: yesIntegrative Conservation, Volume 2, Issue 1, Page 43-61, March 2023., 2023
We apply an integrative perspective to modelling current and future land‐use change in Kuantan, Malaysia, a location with highly biodiverse forests, and also a hotspot of land‐use change. The region is representative of the types of development challenges faced by countries in Southeast Asia, which are also biodiversity hotspots.
Sharun Beream Nasir   +5 more
wiley   +1 more source

International clinical practice recommendations on the definition, diagnosis, assessment, intervention, and psychosocial aspects of developmental coordination disorder – Chinese (Mandarin) translation

open access: yesDevelopmental Medicine &Child Neurology, Volume 61, Issue 3, Page E1-E35, March 2019., 2019
目的 本国际临床指南由欧洲残疾儿童学会(the European Academy of Childhood Disability,EACD)牵头制定,旨在解决发育性协调障碍(developmental coordination disorder,DCD)的定义、诊断、评估、干预以及与社会心理方面的临床应用关键问题。 方法 本指南针对五个领域的关键问题,通过文献综述和专家团队的正式讨论达成共识。为保证指南的循证基础,以“机制”、“评估”和“干预”为检索词, 对2012年更新以来提出的最新建议以及新增的“社会心理问题”和“青少年/成人”为检索词进行检索。根据牛津大学循证医学中心证据等级 (证据水平 [level of evidence, LOE]1–4) 将结果进行分类,最终转化为指南建议。并由国际 ...
Jing Hua   +6 more
wiley   +1 more source

电子附着效应对SF_6断路器灭弧的影响

open access: yes, 1983
本文讨论了SF6气吹断路器中的电弧熄灭问题 ...
林烈
core   +2 more sources

开断器中的电弧现象研究

open access: yes, 1986
开关、断路器中的电弧研究与等离子体化学是低温等离子体两个通常的应用领域。开断器中电弧物理过程的研究结果可应用于回路开断、限止过失电流及脉冲功率系统中。脉冲功率技术可应用于原子能聚变发电及其模拟。随着电力系统的容量不断增加 ...
顾琅
core   +2 more sources

The Effects of Working Memory Updating on Chinese Reading Comprehension Among Bilingual Primary School Students

open access: yesNew Directions for Child and Adolescent Development, Volume 2026, Issue 1, 2026.
Background Working memory updating is crucial in bilingual children′s second language (L2) reading comprehension. A robust updating ability is a cognitive key for children to successfully master L2 reading comprehension. Objective This study is aimed at investigating the effect of updating ability on the L2 Chinese reading comprehension among Uyghur ...
Guangxin Li   +3 more
wiley   +1 more source

基于非结构网格间断有限元方法的不同间断识别器和限制器的比较 [PDF]

open access: yes, 2013
间断有限元方法(DG)在很多问题中显示了很好的性能。但是随着研究的不断深入,对于限制器的研究已经成为限制DG 发展的瓶颈。本文首先介绍了DG 的基本算法,然后详细分析各种不同间断识别器和限制器的原理,包括Cockburn 限制器、Barth 限制器、KXRCF 识别器等 ...
郑洪伟, 赵文赓
core   +2 more sources

Projected Climate Scenarios Reveal an Expanding Suitable Habitat for the Critically Endangered African White‐Backed Vulture Gyps africanus 预测的气候情景揭示了极危非洲白背兀鹫的适宜栖息地不断扩展

open access: yesIntegrative Conservation, Volume 3, Issue 4, Page 398-409, December 2024.
Understanding the potential impacts of projected climate change scenarios on critically endangered species is critical to guide effective conservation planning. Species distribution modelling techniques such as MaxEnt are increasingly becoming important tools for predicting habitat shifts in response to projected climate change scenarios.
Mark Zvidzai   +4 more
wiley   +1 more source

气体灭弧断路器的热力学分析及其过程的数值模拟

open access: yes, 1984
本文提供一个气体灭弧断路器的热力学分析及过程数值模拟计算方法。在电流、电压、机械动作对时间关系及结构参数己知的条件下,用于计算吹冷电弧的外气流热力学参数包括温度、压力及流量对时间的关系。这种计算结果对于压力室 ...
顾琅, 薜明伦
core   +2 more sources

Home - About - Disclaimer - Privacy