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Journal of Mathematics, Volume 2021, Issue 1, 2021., 2021 Fractional order research has interdisciplinary characteristics and has been widely used in the field of natural sciences. Therefore, fractional order research has become an important area of concern for scholars. This paper used 2854 literatures collected from China National Knowledge Infrastructure (CNKI) database from 2001 to 2020 as the data source
Yunfei Yang +4 more
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On the convergence of the secant method in Banach space(Banach空间正割法的收敛性)
Zhejiang Daxue xuebao. Lixue ban, 2002 利用Hernandez M A等所给的在初始点处的相关信息,给出了比Hernandez M A等较为宽松的正割法收敛条件,在得到了类似的误差估计的同时,也给出了的误差估计.
HUANGZheng-da(黄正达)
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Zhejiang Daxue xuebao. Lixue ban, 2019 考虑随机系数自回归模型yt = Φt yt - 1 + ut，其中Φt 为随机系数，ut 为随机误差。在允许Φt 与ut 相依以及无穷的条件下，构造了误差方差的自加权估计，并证明了该估计的渐近正态性。最后通过数值模拟，说明自加权估计的稳健和有效性。
FUKeang(傅可昂) +4 more
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Guangtongxin yanjiu, 2021 针对正交频分复用（OFDM）系统中，压缩采样匹配追踪（CoSaMP）算法在进行信道估计时选择原子更新残差过程中采用最小二乘（LS）估计忽略了噪声影响的问题，文章利用信道时域的稀疏性提出了一种改进的CoSaMP算法。首先利用Co-SaMP算法进行初始信道估计，然后再采用线性最小均方误差（LMMSE）算法对结果进行降噪处理，提高了估计精度。仿真结果表明，在OFDM系统中，改进的CoSaMP算法比传统CoSaMP算法具有更好的均方误差和误码率（BER）估计性能。
雷芳 +4 more
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Zhejiang Daxue xuebao. Lixue ban, 2011 使用一个两阶段最小距离矩估计方法，给出了含有Berkson测量误差和经典线性测量误差的非线性模型估计.得到了参数的一致估计及其渐近正态性.此外，基于傅里叶分析方法推导出了非线性函数的一个识别方程.
XIEQi-chang(解其昌) +1 more
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Zhejiang Daxue xuebao. Lixue ban, 2000 在误差理论和数据处理中，标准偏差σ是一个非常重要的量，它是由下式(1)定义的。由于随机误差δi=xi-x0是相对于真值x0定义的，而真值x0在绝大多数情况下是未知的，所以通常是利用贝赛尔(Bessel)公式(2)对标准偏差σ进行估计。(2)式中是第i次测量的残余误差，这里的xi是第i次测量的测得值，是n次测量的算术平均值。而在n次有限测量中，S实际上是标准偏差σ的估计量。可以证明(3)其中系数bn为(4) 由于用(4)式计算系数bn相当麻烦。为此，本文提出一个计算简便、准确高度 ...
HEKe-ming(何克明)
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Matching expert range maps with species distribution model predictions
Conservation Biology, Volume 34, Issue 5, Page 1292-1304, October 2020., 2020 Abstract Species’ range maps based on expert opinion are a critical resource for conservation planning. Expert maps are usually accompanied by species descriptions that specify sources of internal range heterogeneity, such as habitat associations, but these are rarely considered when using expert maps for analyses.
Kumar Mainali +3 more
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Zhejiang Daxue xuebao. Lixue ban, 2005 利用最大似然估计准则，针对GMSK提出了一种不需要前导字的前馈载波相位和时钟误差联合估计算法，可用于通用的软件无线电结构.给出了这种算法的性能仿真，结果表明算法的误差方差接近参数估计的理论下界——修正Cramer-Rao下界，在高信噪比下比目前其他算法的性能更优，而且可以工作在更低采样率下.算法复杂度低，可以节省硬件资源，增加软件无线电的信号处理带宽.
TANGJin-hua(唐金花) +2 more
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World Water Policy, Volume 12, Issue 1, February 2026.ABSTRACT Urban expansion significantly impacts flood risk, particularly in rapidly growing areas where impervious surfaces exacerbate surface runoff. This study examines spatial patterns of urban growth and their effects on flood exposure in Mecklenburg County, North Carolina, from 2011 to 2021.
Pegah Madadi, Azad Sadeghi
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Journal of Critical Infrastructure Policy, Volume 7, Issue 1, Spring/Summer 2026.ABSTRACT The National Quality Infrastructure (NQI) in a given country provides the essential framework for quality assurance integrating standardization, metrology, accreditation, and conformity assessment to create the technical backbone for industry and trade. Hence, building a resilient NQI is fundamental to securing medicine quality, enabling local
Addisu Afrassa Tegegne +3 more
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