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THE U.S. WITHDRAWAL, TALIBAN TAKEOVER, AND ONTOLOGICAL (IN)SECURITY IN AFGHANISTAN
World Affairs, Volume 186, Issue 1, Page 105-134, Spring 2023., 2023 Security discussions of the Taliban's second takeover of Afghanistan center on physical security threats, neglecting the ontological aspect related to how security entails the metaphysics of life—being, feeling alive, or having a sense of self. This article examines this ontological threat to the Afghan people to complement the security discussion and ...
Thomas Ameyaw‐Brobbey
wiley +1 more source
Statistical matching for conservation science
Conservation Biology, Volume 34, Issue 3, Page 538-549, June 2020., 2020 Abstract The awareness of the need for robust impact evaluations in conservation is growing and statistical matching techniques are increasingly being used to assess the impacts of conservation interventions. Used appropriately matching approaches are powerful tools, but they also pose potential pitfalls.
Judith Schleicher +5 more
wiley +1 more source
Gaoya dianqi, 2022 近些年变压器真空有载分接开关故障频发，严重影响了电网系统的安全稳定运行。油中溶解气体分析是发现真空有载分接开关内部潜伏性电气故障的有效手段。针对当前真空有载分接开关油中溶解气体分析缺乏有效判据的难题，文中在分析了近5年真空有载分接开关的故障案例和604台在运真空有载分接开关油中溶解气体数据的基础上，提出乙炔是反映真空有载分接开关运行状态的主要特征气体，并结合吊芯检查结果提出采用乙炔增长率作为判断真空有载分接开关运行状态的状态量。接着，文中通过多台真空有载分接开关切换模拟试验确定了乙炔增长率的阈值大小 ...
金雷, 周凯, 罗维, 鲁非, 刘睿
doaj
Developmental 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
The Research and Design of an Automatic Flange-welding System [PDF]
, 2011 对人工操作的法兰焊机的工作过程进行仔细研究后,提出了一套方案来设计相应的法兰自动焊机,文中主要介绍所设计的法兰自动焊机系统的结构及工作原理。After careful study of manual controlled flange-welding machine's working process,this paper proposed a solution of design the corresponding automatic flange-welding machine,and ...
易绍祥
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Evolution of research on global amphibian declines
Conservation Biology, Volume 40, Issue 1, February 2026.Abstract In the late 1980s, the scientific community became aware of severe, enigmatic amphibian population declines. These declines triggered a wave of research focused on quantifying their extent and identifying key drivers. We used text‐analysis techniques, including topic modeling and geoparsing, to examine the evolution of research focused on ...
Jordann Crawford‐Ash +6 more
wiley +1 more source
Gaoya dianqi, 2021 真空开关开断电感性负载时,电弧重燃是产生严重操作过电压的根本原因。真空开关选相操作可以消除电弧重燃,避免严重的操作过电压。选相真空开关的机械稳定性是保证可靠选相操作的关键,对选相真空开关的机械稳定性进行在线检测,可及时发现和避免选相失效。文中提出两种选相特性在线检测方法:在选相真空开关的操动机构上设置一个和主触头动作稳定同步的辅助接点,用于触头刚分时刻的信号传感,可实现选相特性的在线检测和选相操作的自适应控制,及时发现选相特性劣化,避免选相失效;通过检测真空开关开断过程中的空间电磁波 ...
郑一鸣 +5 more
doaj
Study on W-25%Cu rolling using Y220 roll mill [PDF]
, 2013 高温强度和抗电弧烧蚀性能优异的钨与高导电导热性铜的良好结合使钨铜复合材料具有一系列优异性能，广泛应用于电触头材料，电子封装和热沉材料。钨与铜的互不相溶性决定了钨铜复合材料制备的特殊性。 分析传统的制备方法及国内外钨铜材料研究现状，发现钨铜合金在经过溶渗法制备后密度、力学性能及电学性能还不能满足工业需求，需要进行后续的机械加工来实现材料的进一步致密。而进行钨铜合金性能优化的加工方法多样，但很少采用轧机机组来加工钨铜合金，国内缺乏相关技术资料。 本文的研究是按照充分利用XX公司资源、节约投入原则进行的 ...
蔡协勇
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Ultrasound in Obstetrics &Gynecology, Volume 65, Issue 5, Page 624-632, May 2025.ABSTRACT Objectives Placental insufficiency contributes to many obstetric pathologies, but there is no bedside clinical tool to evaluate placental perfusion. We have developed a method to acquire multiple three‐dimensional (3D) power Doppler (PD) ultrasound (US) volumes of placental vasculature, with infrared camera tracking of the precise spatial ...
A. Xue +5 more
wiley +1 more source
Field emission vacuum sensor [PDF]
, 2008 场发射真空传感器是采用MEMS加工工艺研制一种新型的基于硅尖阵列场发射原理的微型真空传感器。通过理论分析,确立了该种传感器中硅尖场发射电流与真空度的关系。并利用干法刻蚀工艺,在硅片上制作了高3.2μm,曲率半径小于70nm的200×42硅尖阵列。保持阳极与硅尖距离为1μm的情况下,可以观察到阳极电压为10V左右时开始有明显的场发射电流。实验结果表明,在10V-15V的输入电压范围内,通过测试场发射电流所得到的真空度值,其最大误差不超过10%。该真空传感器具有制作简单、易于集成、信号测量容易 ...
孙道恒, 文尉任, 王凌云
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