内插函数 meaning in Chinese
interpolating function
Examples
- In this paper , the author attempts to discuss two main problems of convolution back projection algorithm basing on fan - beam scanning
本文主要探讨了卷积反投影算法的两个核心问题：卷积窗函数与内插函数。 - Former researchers have done many works in the respect of convolution back projection algorithm . however , according to the result of document retrieval , apart from the study about one the two main problems or a new function used in the reconstruction progress , there is not synthetically study about window function and interpolation methods and effects on quality of ct image
围绕卷积反投影算法的两个问题，前人做了大量的研究，但根据所查阅资料，前人仅就其中一个问题做了一些研究或提出一种新的函数用于图像重建，却并没有全面地分析窗函数与内插函数的特性以及对ct图像的影响情况。 - We propose a chaos - based generation of the random ppm - ps signals , design and implement a generator of the ppm - ps signals . we introduce an if sampling technique and simulate the performances of digital demodulation techniques of using hilbert filters , sine filters , bessel filters and poly - phase filters . the poly - phase filtering method can achieve the higher mirror - frequency rejection ratio by using the low order filters
介绍了中频采样技术，并对希尔伯特滤波法、辛格内插函数修正、贝赛尔函数插值法及多相滤波法等数字解调算法进行了计算机仿真和性能比较，指出多相滤波法能以较低的阶数实现较高的镜频抑制比。 - In the terms of interpolation , the image reconstructed from nearest interpolation or linear interpolation has good edge but serious noise ; reconstruction from 4 * 4cubic interpolation or three b - spline or three - order lagrange interpolations has better local character . 2 x 2cubic interpolations which has both better edge and local character is the ideal interpolation , the following is the basic principle during reconstruction : ( 1 ) the more width of interpolation , the more number of summation and the more order of interpolation polynomial , the higher of density resolution ; ( 2 ) the more of interpolation polynomial and width of interpolation , the more of reconstruction time simultaneously , aimed at eliminating the effects of noise contained in projection data , in this paper , author analysis cause and effects of common artifacts . importantly , discusses convolution back - projection reconstruction algorithm with a shift axis of rotation has been derived for correcting images that acquired with a divergence axis of rotation using the fan beam geometry with an angle - equaled detector
在ct图像重建时，选择有限带宽窗有较好的空间分辨率，三角形窗有较好的密度分辨率，选择余弦窗则使得空间分辨率与密度分辨率的折衷；从窗函数的频谱角度来讲，可以用于图像重建的一个良好的卷积窗函数应该具备以下条件： ( ? )小的3db带宽b ，即最小的主瓣宽度； ( ? )最小的旁瓣最大峰值a ； ( ? )最大的旁瓣峰值衰减速度d ；就内插函数而言，临近点内插与线性内插重建图像噪声大，但有较好的边缘与细节； 4 4三次内插、三次b -样条与四次拉格朗日多项式内插图像平滑，局部特性较好。 - Basing on the result of former research , this paper synthetically analysis character of common window function and interpolation , author has conclude a few of basic principle during choosing windows function and interpolation in the process of ct image reconstruction in the terms of windows , among of the introduced windows , band - limited window , triangle window and cosine window must be the ideals choose
基于前人的研究成果，本文综合分析了常见窗函数与内插函数的特性。理论分析和实验结果得出可供选择的选择窗函数与内插函数以及如何根据实际检测目的来选择较好参函数所遵循的原则。