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991.
Ohne Zusammenfassung
相似文献
相似文献
992.
993.
Zalman Rubinstein 《Aequationes Mathematicae》1981,23(1):108-117
Several characteristic functional equations satisfied by classes of polynomials of bounded degree are examined in connection with certain generalizations of the Morera-Carleman Theorem. Certain functional equations which have nonanalytic polynomial solutions are also considered. 相似文献
994.
995.
A. E. Brouwer 《Combinatorica》1982,2(4):333-340
We prove that any regular near hexagon with 729 vertices and lines of size 3 is derived from the ternary Golay code, thus
settling the last case in doubt among the regular near hexagons with lines of size 3. 相似文献
996.
Ph. Cahuzac J. L. LeGouët P. E. Toschek R. Vetter 《Applied physics. B, Lasers and optics》1979,20(1):83-88
Laser induced nonlinear absorption profiles in a three-level system have been recorded to study the effect of elastic collisions
upon optical coherences. In our particular system, the signal is due to a pure double-quantum term, where we have separated
the effect of phase-interrupting collisions from the effect of velocity-changing collisions. Experimental results show that
the effect of velocity-changing collisions is very small, and that broadening of the signal is due to phase-interrupting collisions
mainly. We are able to determine the increase of the decay rate of the coherent superposition (the “coherence”) of two levels
of same parity [Dγ
13/dp=(6.5±1) MHz/Torr] and an upper limit for the mean velocity change (ũ≲5m/s). 相似文献
997.
Convergence in probability for Toeplitz weighted sums is obtained for convex tight random elements in D[0, 1] under pointwise conditions. The almost sure convergence of the weighted sums is proved for independent, convex tight random elements and for independent, identically distributed random elements. Special techniques and concepts are developed in order to obtain these results in the Skorohod topology of D[0, 1]. 相似文献
998.
M.A. Chmielewski 《Journal of multivariate analysis》1980,10(3):343-350
The usual assumption in multivariate hypothesis testing is that the sample consists of n independent, identically distributed Gaussian m-vectors. In this paper this assumption is weakened by considering a class of distributions for which the vector observations are not necessarily either Gaussian or independent. This class contains the elliptically symmetric laws with densities of the form f(X(n × m)) = ψ[tr(X ? M)′ (X ? M)Σ?1]. For testing the equality of k scale matrices and for the sphericity hypothesis it is shown, by using the structure of the underlying distribution rather than any specific form of the density, that the usual invariant normal-theory tests are exactly robust, for both the null and non-null cases, under this wider class. 相似文献
999.
Erich Bohl 《Numerische Mathematik》1980,34(2):111-124
Summary The numerical treatment of discrete bifurcation problems (2) with chord methods or Newton's method is a question of constructing appropriate initial approximations to prevent the sequence from converging to the trivial solution. This problem is being discussed under conditions which are satisfied for quite a few examples arising in applications (see Sect. 3). 相似文献
1000.
P. Deuflhard 《Numerische Mathematik》1979,33(2):115-146
Summary A numerically applicable stepsize control for discrete continuation methods of orderp is derived on a theoretical basis. Both the theoretical results and the performance of the proposed algorithm are invariant under affine transformation of the nonlinear system to be solved. The efficiency and reliability of the method is demonstrated by solving three real life two-point boundary value problems using multiple shooting techniques. In two of the examples bifurcations occur and are significantly marked by sharp changes in the stepsize estimates. 相似文献