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141.
We explicitly calculate the normal cones of all monomial primes which define the curves of the form , where . All of these normal cones are reduced and Cohen-Macaulay, and their reduction numbers are independent of the reduction. These monomial primes are new examples of integrally closed ideals for which the product with the maximal homogeneous ideal is also integrally closed.
Substantial use was made of the computer algebra packages Maple and Macaulay2.
142.
Francis Jordan Sam B. Nadler Jr. 《Proceedings of the American Mathematical Society》2001,129(4):1219-1228
It is shown that a continuum that is an space in the sense of Michael must be hereditarily decomposable. This improves known results, thereby providing more evidence that such continua must be dendrites.
143.
M. V. Korolevich R. G. Zhbankov L. V. Matusevich B. G. Derendyaev V. N. Piottukh-Peletskii 《Journal of Applied Spectroscopy》2001,68(6):930-941
The frequencies of the normal vibrations of the molecules of 2,6- and 3,6-di-O-nitro-methyl--D-glucopyranosides and 2,3,6-tri-O-nitro-methyl--D-glucopyranoside have been calculated within the valence-force-field approximation in combination with calculation of the absolute intensities of the IR absorption bands of these molecules by the CNDO/2 method. The regularities in the structure of the complex IR absorption bands characteristic for nitro groups formed as a result of selective nitrosubstitution have been explained. 相似文献
144.
S. F. Shkirman N. A. Sokolov V. K. Konstantinova K. N. Solov'ev 《Journal of Applied Spectroscopy》2001,68(3):410-414
Quasiline electronicvibrational spectra of fluorescence and absorption (excitation of fluorescence in selective recording) of the molecules of phthalocyanine deuterated around the periphery of benzene rings (H2Phcd
16) and the center of the macrocycle (D2Phc) are obtained. The vibrational frequencies of the ground state are almost insensitive to this deuteration (except for vibrations with the participation of angular deformations). In excitation spectra, changes in deuteration are more pronounced due to the effects of nonadiabatic vibronic interaction of the vibrational sublevels of the S
1 state and of the purely electronic level S
2. 相似文献
145.
A class of subsets of
d
which can berepresented as locally finite unions of sets with positive reach isconsidered. It plays a role in PDE's on manifolds with singularities.For such a set, the unit normal cycle (determining the d – 1curvature measures) is introduced as a (d – 1)-currentsupported by the unit normal bundle and its properties are established.It is shown that, under mild additional assumptions, the unit normalcycle (and, hence, also the curvature measures) of such a set can beapproximated by that of a close parallel body or, alternatively, by themirror image of that of the closure of the complement of the parallelbody (which has positive reach). Finally, the mixed curvature measuresof two sets of this class are introduced and a translative integralgeometric formula for curvature measures is proved. 相似文献
146.
Xian Zhou Xiaoqian Sun Jinglong Wang 《Annals of the Institute of Statistical Mathematics》2001,53(4):760-768
Let X
1, , X
n
(n > p) be a random sample from multivariate normal distribution N
p
(, ), where R
p
and is a positive definite matrix, both and being unknown. We consider the problem of estimating the precision matrix –1. In this paper it is shown that for the entropy loss, the best lower-triangular affine equivariant minimax estimator of –1 is inadmissible and an improved estimator is explicitly constructed. Note that our improved estimator is obtained from the class of lower-triangular scale equivariant estimators. 相似文献
147.
George Iliopoulos 《Annals of the Institute of Statistical Mathematics》2001,53(3):436-446
In this paper the problem of estimating the ratio of variances, , in a bivariate normal distribution with unknown mean is considered from a decision-theoretic point of view. First, the UMVU estimator of is derived, and then it is shown to be inadmissible under two specific loss functions, namely, the squared error loss and the entropy loss. The derivation of the results is done by conditioning on an auxiliary negative binomial random variable. 相似文献
148.
Spiros A. Argyros 《Proceedings of the American Mathematical Society》2001,129(11):3231-3239
It is shown that every separable Banach space universal for the class of reflexive Hereditarily Indecomposable space contains isomorphically and hence it is universal for all separable spaces. This result shows the large variety of reflexive H.I. spaces.
149.
Weak L
2
-solutions u of the Schrödinger equation, –u + q(x) u – u = f(x) in L
2
, are represented by a Fourier series using spherical harmonics in order to prove the following strong maximum and anti-maximum principles in
(N 2): Let 1 denote the positive eigenfunction associated with the principal eigenvalue 1 of the Schrödinger operator
. Assume that the potential q(x) is radially symmetric and grows fast enough near infinity, and f is a `sufficiently smooth' perturbation of a radially symmetric function, f 0 and 0 f / C const a.e. in
. Then u is 1-positive for - < < 1 (i.e., u c 1 with c const > 0) and 1-negative for 1 < < 1 + (i.e., u –c1 with c const > 0), where > 0 is a number depending on f. The constant c > 0 depends on both and f. 相似文献
150.
G. Krupa 《Set-Valued Analysis》2000,8(3):237-251
We present the Komlós theorem for multivalued functions whose values are closed (possibly unbounded) convex subsets of a separable Banach space. Komlós theorem can be seen as a generalization of the SLLN for it deals with a sequence of integrable multivalued functions that do not have to be identically distributed nor independent. The Artstein–Hart SLLN for random sets with values in Euclidean spaces is derived from the main result. Finally, since the main theorem concerns multifunctions whose values are allowed to be unbounded, we can restate it in terms of normal integrands (random lower semicontinuous functions). 相似文献