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在数据采集中采用带通采样,可大大降低采样率,但系统中的抗混叠滤波器会造成相位的非线性。采用对滤波后的信号进行带通采样,然后再用FRR滤波器校正相位的非线性,从而不失真地还原原信号,最后在Matlab中进行仿真,验证了该方法的有效性。 相似文献
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P. Le Bars 《Journal of Combinatorial Theory, Series A》2006,113(8):1771-1782
The aggregate error locator is defined and a computation method is given. The aggregate error locator is then used in a type of Forney algorithm to compute the error values in the received words of a Ca,b algebraic geometry code. 相似文献
5.
L. Verger J. P. Bonnefoy F. Glasser P. Ouvrier-Buffet 《Journal of Electronic Materials》1997,26(6):738-744
There has been considerable recent progress in II-VI semiconductor material and in methods for improving performance of the
associated radiation detectors. New high resistivity CdZnTe material, new contact technologies, new detector structures, new
electronic correction methods have opened the field of nuclear and x-ray imaging for industrial and medical applications.
The purpose of this paper is to review new developments in several of these fields. In addition, we will present some recent
results at LETI concerning first the CdTe 2-D imaging system (20 × 30 mm2 with 400 × 600 pixels) for dental radiology and second the CdZnTe fast pulse correction method applied to a 5 × 5 × 5 mm3 CdZnTe detector (energy resolution = 5% for detection efficiency of 85% at 122 keV) for medical imaging. 相似文献
6.
本文提出生种新的带限信号的外推方法,该方法能够很好地抑制噪声干扰,且计算复杂性较低,本文给出算法,证明了收敛性,最后给出了误差计算机实验结果。 相似文献
7.
工艺系统刚度产生的误差原理与分析 总被引:2,自引:0,他引:2
李海明 《电子工业专用设备》2002,31(1):41-44
根据对工艺系统受力变形的分析 ,阐述了工艺系统刚度对零件加工精度的影响 ,并简要提出了提高工艺系统刚度的办法 相似文献
8.
Kirk L. Shanahan 《Thermochimica Acta》2006,441(2):210-214
Dr. E. Storms has published a Letter [E. Storms, Comment on papers by K. Shanahan that propose to explain anomalous heat generated by cold fusion, Thermochim. Acta, 2006] in which he argues that in a sequence of recent papers, the apparent excess heat signal claimed by Dr. Shanahan to arise from a calibration constant shift is actually true excess heat. In particular he proposes that the mechanisms proposed that foster the proposed calibration constant shifts cannot occur as postulated for several reasons. As well, he proposes Shanahan has ignored the extant data proving this. Because this Letter may lend unwarranted support to acceptance of cold fusion claims, these erroneous arguments used by Storms need to be answered. 相似文献
9.
本文针对一类非饱和土壤水流问题,提出了基于二次插值的特征差分格式,得到了严谨的L2模误差估计.并作了数值试验,指明方法的有效性. 相似文献
10.
In this paper, an adaptive FE analysis is presented based on error estimation, adaptive mesh refinement and data transfer for enriched plasticity continua in the modelling of strain localization. As the classical continuum models suffer from pathological mesh-dependence in the strain softening models, the governing equations are regularized by adding rotational degrees-of-freedom to the conventional degrees-of-freedom. Adaptive strategy using element elongation is applied to compute the distribution of required element size using the estimated error distribution. Once a new mesh is generated, state variables and history-dependent variables are mapped from the old finite element mesh to the new one. In order to transfer the history-dependent variables from the old to new mesh, the values of internal variables available at Gauss point are first projected at nodes of old mesh, then the values of the old nodes are transferred to the nodes of new mesh and finally, the values at Gauss points of new elements are determined with respect to nodal values of the new mesh. Finally, the efficiency of the proposed model and computational algorithms is demonstrated by several numerical examples. 相似文献