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31.
本文研究了如何构造满足精度条件的小波滤波器.利用频域分析方法,给出了关于尺度函数精度条件的新结果以及满足精度条件的几个例子. 相似文献
33.
For the contact of two finite portions of interacting rigid crystalline surfaces, we compute the pinning energy barrier dependency on the misfit angle and contact area. This simple model allows us to investigate a broad contact-size and angular range, thus obtaining the statistical properties of the energy barriers opposing sliding for a single asperity. These data are used to generate the distribution of static frictional thresholds for the contact of polycrystals, as in dry or even lubricated friction. This distribution is used as the input of a master equation to predict the sliding properties of macroscopic contacts. 相似文献
34.
With the experimental binding energies and configurations, the root-mean-square radii of p-wave valence neutron distributions for nuclei up to the second p-shell have been calculated in the framework of the single-particle potential model. By analyzing the relations between the radii and the binding energies, the scaling laws of p-wave valence neutron distributions are obtained. The quantitative conditions for the formation of p-wave neutron halos are deduced from these scaling laws. Based on the investigation on the probability of finding the valence nucleon outside the range of the interaction potential, a 2p3/2 halo state in 47S is anticipated for the first time. These obtained results might provide reference for searching for p-wave neutron halos in nuclei up to the second p-shell. 相似文献
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This paper discusses scaling of mixing during miscible flow in heterogeneous porous media. In large field systems dispersivity appears to depend on system length due to heterogeneities. Three types of scaling are discussed to investigate the heterogeneous effects. Dimensional analysis of mixing during flow through geometerically scaled heterogeneous models is illustrated using measured dispersion. Fractal analysis of mixing in statistically scaled heterogeneous porous media is discussed. Analog scaling of pressure transients in heterogeneous porous media is suggested as an in-situ method of estimating dispersion.Notation L
Length
- M
mass
- t
time, (1) indicates dimensionless
- a
dispersivity (L)
- V
local velocity (L/t)
- c
concentration (l).
- v
velocity (L/t)
- C1
fluid compressibility (Lt2/M)
- v
time averaged velocity (LJt)
- D
dispersion VA)
- W
width (L)
- D
fractional dimension (1)
- x
coordinate (L)
- d
Euclidean dimension (1)
- Y
Y=In \-k (l)
- \-d
average particle size (L)
- y
coordinate (L)
- g
acceleration due to gravity (L/t2)
- c
fractal cutoff (L)
- \-k
average permeability (L2)
-
viscosity (LM/t)
- L
length (L)
-
porosity (1)
- L
correlation scale (1/L)
-
density (N/L3)
- N
Number of sites (l)
- 2
variance (dimension depends on variable)
- p
pressure (W/t2L)
-
spectral exponent (l)
- [R]
randomnumber (1)
- r
radius (L)
- t
time (t) 相似文献
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A useful pulse sequence for measuring long‐range C? H coupling constants (JC? H) named high resolution‐HMBC (HR‐HMBC) has been developed. In this pulse sequence, the J‐scaling pulse [(nt1)/2? 180° (H/C) ? (nt1)/2] is incorporated after the spin evolution period, and then followed by an 1H 180° pulse to reverse the magnetization of JC? H couplings. As a result, splittings of the cross peaks due to the long‐range JC? H are realigned with separations of nJC? H along the F1 dimension, and thus even the small long‐range JC? H values can easily be determined. The efficiency of measuring the long‐range JC? H using the proposed pulse sequences has been demonstrated in application to the complicated natural product, portmicin. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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