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951.
952.
P. K. Sen 《Annals of the Institute of Statistical Mathematics》1962,14(1):119-131
Summary The usual non-parametric multi-sample location tests are based on the assumed identity of the scale parameters of the different
cumulative distribution functions (cdf’s). Here is considered the problem of testing the homogeneity of the location parameters
without assuming the identity of the corresponding scale parameters. Such a test appears to be very rare in the literature
on non-parametric location tests, and the necessary modifications with a class of tests based on certain U-statistics and
order statistics, have been discussed here.
This paper was read before the Statistics Section of the 48th Indian Science Congress Session held at Roorkee, 1961. 相似文献
953.
The parametric excitation of acoustohelicon waves has been studied in a piezoelectric semiconductor in the presence of a strong high frequency oscillatory electric field. The threshold electric field amplitude and the growth rate of the unstable mode have been obtained analytically and for n-InSb at 77 K the unstable mode is found to be propagating with a growth rate ~103 s?1 when the crystal is irradiated with a 10.6 μm CO2 laser. 相似文献
954.
A systematic study of absorption, excitation and fluorescence spectra of ammonium chloride activated by varied amounts of lead concentration have been made for the first time. Absorption bands at 6.08, 5.69, 4.73 and 4.57 eV at room temperature and fluorescence bands at 3.62 and 2.85 eV at liquid nitrogen temperature have been observed. These investigations provide an experimental evidence for the existence of two types of centres involved in the luminescence process. 相似文献
955.
956.
957.
The selective formation of 1,3,5,7-tetrazacyelooctanes from the title compounds is described. Exclusive cleavage of the IN-CH2-N bonds at the bridge methylene is shown to be a facile process, thus providing a convenient route to tetrazacyclooctane derivatives. 相似文献
958.
Manabu Senō Shinji Tsuchiya 《Journal of Electron Spectroscopy and Related Phenomena》1976,8(2):165-168
Dichlorobis(1,1-dimethyl-1-p-nitrobenzylamine-2-acetimide-N) palladium(II) and dichlorobis(1,1-dimethyl-1-benzylamine-2-acetimide-N)palladium(II) were newly synthesized and the X-ray photoelectron spectra of the complexes were investigated.The values of the nitrogen 1s binding energy of these complexes and related compounds show that there is a net electron transfer from the nitrogen atom to the palladium atom in the complexes. 相似文献
959.
Summary An estimator of the asymptotic variance of (a randomly stopped) linear combination of a function of order statistics is considered and its asymptotic normality is studied under appropriate regularity conditions. A comparative study of the regularity conditions pertaining to the asymptotic normality and strong convergence of linear combinations of functions of order statistics and their estimated asymptotic variances is also made.Research supported by the Office of Naval Research under ONR Contract N00014-79-C-0522This research is dedicated to Professor Leopold Schmetterer on the occasion of his 60th birthday 相似文献
960.
The parametric excitation of a low frequency wave has been investigated analytically in a two-hole species semiconductor-plasma in the region of kl ? 1 using the hydrodynamic model of the plasmas in the presence of a high frequency oscillatory electric field (E0 cos ω0t applied along the X-axis) and a d.c. magnetic field B0 normal to the electric field (along the Z-axis), the low frequency wave propagating in the X–Z plane making a very small angle θ with the X-axis. The system supports a purely growing unstable mode. The variation of the growth rate of the unstable mode has been studied over a wide range of system parameters for the specific case of an intrinsic GaAs crystal at 300 K. The oscillatory electric field can be obtained by irradiating the crystal with a 119μm H2O laser. 相似文献