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81.
Based on the neutron induced fission fragment mass distribution data up to neutron energy 20 MeV measured with the double kinetic energy method (KEM) and the radio active method (RAM), the systematics of fission fragment mass distribution was investigated by using 5 Gaussian model and the systematics parameters were obtained by fitting the experimental data. With the systematics, the yields of any mass A and at any energy in the region from 0 to 20 MeV of neutron energy can be calculated. The calculated results could well reproduce the experimental data measured with KEM, but show some systematical deviation from the data measured by RAM, which reflects some systematical deviations between the two kinds of measured data.The error of systematics yield was calculated in an exact error transformation way, including from the error of the experimental yield data to the error of the discrete parameters, then to the systematics parameters,and at last to the yield calculated with systematics. 相似文献
82.
Eero Hyry 《Compositio Mathematica》2002,130(3):319-343
Let A be a local ring, and let I
1,...,I
r
A be ideals of positive height. In this article we compare the Cohen–Macaulay property of the multi–Rees algebra R
A
(I
1,...,I
r
) to that of the usual Rees algebra R
A
(I
1 ··· I
r
) of the product I
1 ··· I
r
. In particular, when the analytic spread of I
1 ··· I
r
is small, this leads to necessary and sufficient conditions for the Cohen–Macaulayness of R
A
(I
1,...,I
r
). We apply our results to the theory of joint reductions and mixed multiplicities. 相似文献
83.
An adaptive trust region method and its convergence 总被引:17,自引:0,他引:17
In this paper, a new trust region subproblem is proposed. The trust radius in the new subproblem adjusts itself adaptively.
As a result, an adaptive trust region method is constructed based on the new trust region subproblem. The local and global
convergence results of the adaptive trust region method are proved. Numerical results indicate that the new method is very
efficient. 相似文献
84.
Starting with an initial vector λ = (λ(κ))κ∈z ∈ ep(Z), the subdivision scheme generates asequence (Snaλ)∞n=1 of vectors by the subdivision operator Saλ(κ) = ∑λ(j)a(k - 2j), k ∈ Z. j∈zSubdivision schemes play an important role in computer graphics and wavelet analysis. It is very interesting tounderstand under what conditions the sequence (Snaλ)∞n=1 converges to an Lp-function in an appropriate sense.This problem has been studied extensively. In this paper we show that the subdivision scheme converges forany initial vector in ep(Z) provided that it does for one nonzero vector in that space. Moreover, if the integertranslates of the refinable function are stable, the smoothness of the limit function corresponding to the vectorλ is also independent of λ. 相似文献
85.
Ye Yanqian 《数学年刊B辑(英文版)》1994,15(4):489-492
A Theorem is given on the number of passages passing throgh a multiply-connected region,which corrects a wrong conjecture in a former paper of the author. 相似文献
86.
A quantum-mechanical theory of joint nonideal measurement of incompatible polarization observables is applied to an EPR-like experiment. It is demonstrated that this experiment yields both information satisfying and information violating the Bell inequalities. The measurement is also discussed in the context of a local hidden-variables theory. It is argued that the violation of an additional assumption of reproducibility of the hidden variable rather than violation of locality may be responsible for the violation of the Bell inequalities. 相似文献
87.
The truncated Newton algorithm was devised by Dembo and Steihaug (Ref. 1) for solving large sparse unconstrained optimization problems. When far from a minimum, an accurate solution to the Newton equations may not be justified. Dembo's method solves these equations by the conjugate direction method, but truncates the iteration when a required degree of accuracy has been obtained. We present favorable numerical results obtained with the algorithm and compare them with existing codes for large-scale optimization. 相似文献
88.
XIUNAIHUA 《高校应用数学学报(英文版)》1995,10(4):439-448
In this paper we prove that a class of trust region methods presented in part Ⅰ is superlinearly convergent. Numerical tests are reported thereafter. Results by solving a set of typical problems selected from literatures have demonstrated that our algorithm is effective. 相似文献
89.
A tolerance region is a map from the sample space of one statistical model to the event space of a second statistical model having the same parameter. This paper derives an optimum β-expectation tolerance region for the multivariate regression model. A measure of power is proposed and evaluated. 相似文献
90.