Results 21 to 30 of about 17,002 (171)
Guangtongxin yanjiu, 2010 文章研究了45-°0-°45°相位延迟型偏振控制器的控制算法,对相位延迟量引入的误差进行了分析,并通过仿真得到输出偏振态的方位角误差和椭率角误差与延迟量误差之间的关系。结果表明,延迟量误差对该偏振控制器输出偏振态的椭率角误差的影响小于对方位角误差的影响。还分析了入射光波长误差导致的延迟量误差对输出偏振态精度的影响,仿真结果表明,45-°0-°45°相位延迟型偏振控制器是对波长敏感的。
廖延娜, 姚娟, 阴亚芳
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The Political Empowerment of Women and Industrialization in Africa
Politics &Policy, Volume 53, Issue 6, December 2025.ABSTRACT This study examines the effect of political empowerment of women on industrialization in Africa. The results, after controlling for cross‐sectional dependence, show that women's political implication causes industrialization. The fixed effects Driscoll/Kraay standard error and the GMM estimators reveal that women's political empowerment ...
Tii N. Nchofoung +2 more
wiley +1 more source
Gaoya dianqi, 2019 电力系统一次设备进行带电检测可以降低运维成本、减少设备故障率,是电网发展的必然趋势。电网系统使用电压互感器数量庞大,不仅难以全部实现离线检测,而且电压互感器中的电容式电压互感器（CVT）电容单元为敞开式结构,其分压比受到变电站内电磁环境影响,最终反映到离线误差数据与在运误差数据之间存在偏差。为确定磁场干扰对误差影响程度,借助有限元分析离线误差试验状态与在运误状态时电磁环境对CVT内部初始电压单元的改变,结合实际工程选择站内符合误差检测要求的电磁式电压互感器作为参比标准器对在运CVT进行带电误差检测 ...
王欢 +4 more
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RETRACTED: The Growing Tide of Antiscience Sentiment: A Global Concern
World Medical &Health Policy, Volume 17, Issue 3, Page 529-537, September 2025.ABSTRACT The growing tide of antiscience sentiment represents a critical global challenge, with particularly visible manifestations in the United States. This viewpoint examines how the rejection of scientific consensus threatens academic institutions, public health, and technological progress worldwide.
Thorsten Rudroff
wiley +1 more source
Jixie chuandong, 1998 摆线针轮行星减速机的传动误差是其内部各零部件的制造误差、装配误差和修形原理误差的函数。运用齿轮啮合原理 ,从减速机的制造过程和装配过程出发 ,可以建立较符合工程实际的数学模型并进而推导出减速机传动误差的解析计算方法。通过单因素分析 ,可以了解各种单项制造误差因素对减速机传动误差的影响程度。通过对传动误差进行统计计算 ,可以对减速机的优化设计 ...
姚文席
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New Phytologist, Volume 247, Issue 2, Page 504-517, July 2025.Summary Repetitive DNA is a feature of all organisms, ranging from archaea and plants to humans. DNA repeats can be seen both in coding and in noncoding regions of the genome. Due to the recurring nature of the sequences, simple DNA repeats tend to be more prone to errors during replication and repair, resulting in variability in their unit length ...
Sridevi Sureshkumar +3 more
wiley +1 more source
Guangtongxin yanjiu, 2021 在星间激光通信中，精跟踪单元常采用四象限探测器用于光斑位置定位，定位误差的大小直接影响精跟踪单元的测角精度。为实现微弧度量级的测角精度，文章研究了影响探测器定位误差的各个噪声因素，并根据星间光通信的实际情况进行了简化分析，提出了定位误差的具体计算方法，最后通过具体算例评估了各噪声因素的影响程度。研究结果表明，提高发射功率可以在一定范围内提高接收端信号的信噪比，减小定位误差，进而减小测角误差，提高测角精度。但定位误差并非随发射功率的增大而线性减小，当发射功率增大到一定程度之后，定位误差的减小有限 ...
李树德 +4 more
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Latin American Policy, Volume 16, Issue 2, June 2025.ABSTRACT This article examines the academic literature and reports on Colombia's National Development Plans over the past 50 years. It aims to identify the central debates regarding Colombia's development model, addressing a series of contradictions, path‐dependent outcomes, salient variations, and issue framing.
Alberto Lioy, Felipe Jaramillo Ruiz
wiley +1 more source
Jixie chuandong, 1992 本文用三维有限元——数学规划方法,分析了窄斜齿轮在误差条件下的三维接触状况,包括压力角误差、螺旋角误差、基节误差、齿轮修形、以及由于齿轮支承变形引起的啮合误差的影响,进一步分析了误差存在时载荷大小对接触状态的影响。通过计算得到各种情况下的齿面载荷分布和齿轮副的振动激励——传动误差,为斜齿轮传动的动、静强度分析提供了可靠的依据。
方宗德, 沈允文
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Gaoya dianqi, 2020 随着特高压工程的推进,CT现场校验成为亟需解决的难题。由于国内外对此问题研究尚属空白,为解决该难题,提出将实验室CT校验用的自校法应用于现场交接试验。在解决了一系列自校法工程应用问题的基础上,重点针对CT校验误差展开研究。首先分析了具有自校功能CT的结构特征,并在此基础上根据CT误差定义对其误差特性进行了理论分析;讨论了影响误差的主要因素;为计算误差大小,建立了基于有限元法瞬态场—路耦合CT误差分析模型;利用该模型分别对CT两种工作模式（测量用和校验用）下的误差进行计算,并与实际测量结果比较。结果表明 ...
吴细秀 +5 more
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