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31.
韩国强 《高校应用数学学报(A辑)》1994,(3)
本文我们讨论了矩形域上带连续边界条件的一类多元散乱数据最优插值。给出了某些情形插值的误差估计,误差估计表明在某些点上还具有超收敛性。 相似文献
32.
Error bounds for asymptotic expansions of the distribution of the MLE in a GMANOVA model 总被引:1,自引:0,他引:1
Yasunori Fujikoshi 《Annals of the Institute of Statistical Mathematics》1987,39(1):153-161
Summary In this paper we obtain asymptotic expansions for the distribution function and the density function of a linear combination
of the MLE in a GMANOVA model, and for the density function of the MLE itself. We also obtain certain error bounds for the
asymptotic expansions. 相似文献
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34.
In two-phase materials, each phase having a non-local response in time, it has been found that for some driving fields the response somehow untangles at specific times, and allows one to directly infer useful information about the geometry of the material, such as the volume fractions of the phases. Motivated by this, and to obtain an algorithm for designing appropriate driving fields, we find approximate, measure independent, linear relations between the values that Markov functions take at a given set of possibly complex points, not belonging to the interval [-1,1] where the measure is supported. The problem is reduced to simply one of polynomial approximation of a given function on the interval [-1,1] and, to simplify the analysis, Chebyshev approximation is used. This allows one to obtain explicit estimates of the error of the approximation, in terms of the number of points and the minimum distance of the points to the interval [-1,1]. Assuming this minimum distance is bounded below by a number greater than 1/2, the error converges exponentially to zero as the number of points is increased. Approximate linear relations are also obtained that incorporate a set of moments of the measure. In the context of the motivating problem, the analysis also yields bounds on the response at any particular time for any driving field, and allows one to estimate the response at a given frequency using an appropriately designed driving field that effectively is turned on only for a fixed interval of time. The approximation extends directly to Markov-type functions with a positive semidefinite operator valued measure, and this has applications to determining the shape of an inclusion in a body from boundary flux measurements at a specific time, when the time-dependent boundary potentials are suitably tailored. © 2022 Wiley Periodicals, Inc. 相似文献
35.
36.
以船用内燃机油为研究对象,利用原子发射光谱对润滑油中的添加剂成分进行量化确定。根据MOA原子发射光谱仪的工作原理,选择校正曲线法定量,提出对不在测量精度范围内的添加剂元素含量用0 μg·g-1的空白标油进行稀释测量的方法,并进行误差计算。试验结果表明,添加剂各元素钙、磷和锌的测量相对标准偏差分别为1.6%,4.8%和4.6%,样品稀释前后的测量误差结果分别为4.21%,6.99%和5.09%。 相似文献
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38.
针对在未做隔离保护处理的环境中,基于Michelson干涉原理的激光干涉仪测量系统存在严重的干扰误差,不适合分步式压印光刻纳米级对准测量的要求.采用Edlen公式的分析及计算,不仅在理论上揭示出环境温度、湿度、气压等变化对激光干涉仪测量准确度的影响,而且证明影响测量准确度的最大干扰源是空气流动的结果.通过气流隔离措施和系统测量反馈校正控制器,能够实时补偿激光干涉仪两路信号的相差.最终,测量漂移误差在10 min内由13 nm降低到5 nm以内,满足压印光刻在100 mm行程中达到20 nm定位准确度要求. 相似文献
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40.
Mukesh Chopra Manish Bhardwaj Muralidhar Kulkarni Asok De R. K. Sinha 《Fiber and Integrated Optics》2002,21(4):253-268
We present the design of a 3-dimensional (3-D) noncoherent optical hybrid network. We also report the design of a new family of 3-D codes for fiber optic hybrid networks. We show that the hybrid network allows for shorter bit times and a higher number of users, given a set chip rate, compared to previously conceived networks. These newly designed hybrid single-pulse-per-row (HSPR) codes have very low autocorrelation side-lobes and very small cross-correlation peaks. We compare the performance of our hybrid model using our codes with the Optical Orthogonal Codes (OOCs) and Temporal/Spatial (T/S) codes and show that the new network can support a greater number of users and higher data rates than those using OOCs and T/S codes. 相似文献