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81.
Determination of major and trace elements in crude oils by neutron activation and reflection methods
J. Csikai S. M. Al-Jobori Cs. M. Buczkó S. Szegedi 《Journal of Radioanalytical and Nuclear Chemistry》1982,71(1-2):215-223
The concentrations of O, Na, Cl, V, Mn and Ni in crude oils of different origins were determined, using sampling (SNAA) and
on-stream (ONAA) activation analyses. Samples were irradiated with thermal and fast neutrons produced by a 0.3 mg252Cf source and a 14 MeV generator. The H-content and the C/H atomic ratio have been determined by thermal neutron reflection
method using an 18 GBq Pu−Be source.
This work was supported in part by the Hungarian Academy of Sciences. 相似文献
82.
The theme of the article is the study of the unipotent part of Arthur’s trace formula for general linear groups. The case of regular (or “regular by blocks”) unipotent orbits has been treated in another paper (cf. [10]). Here we are interested in the contribution of Richardson orbits that are induced by Levi subgroups with two-by-two distinct blocks. In this case, the contribution is remarkably given by a global unipotent weighted orbital integral. As a corollary, we get integral formulas for some of Arthur’s global coefficients. We also present a new construction of Arthur’s local unipotent weighted orbital integral and an explicit computation of some of them. 相似文献
83.
84.
Summary In the proof of the main result of the original paper there is an error. Instead of repairing that proof to get just the original result, at the critical spot we improve the proof and obtain a much better result. In particular, we approximate the product-limit and empirical cumulative hazard processes by suitable copies of the corresponding limiting Gaussian processes with rates of approximation that on appropriate fixed half lines reduce to the rates of Komlós, Major and Tusnády for the uncensored empirical process. 相似文献
85.
Á Császár 《Acta Mathematica Hungarica》2002,95(1-2):83-99
We study properties of the operation
, defined for structures corresponding to different subcategories of MER, as merotopies, filter merotopies, contiguities,
-contiguities and closures. In particular, we examine commutativity of
and the operation according to which a structure induces a structure of another type (as e.g.\ a merotopy induces a closure) and the inverse operations of the former. 相似文献
86.
87.
Miklós Csörgő 《Journal of multivariate analysis》1979,9(1):84-100
Hoeffding (Ann. Math. Statist. 1948) and Blum, Kiefer and Rosenblatt (Ann. Math. Statist. 1961) constructed distribution free tests of independence based on a multivariate empirical process. We establish strong invariance principles for the latter and also for appropriate functionals of it. 相似文献
88.
It is well known that the recurrence relations
are periodic, in the sense that they define periodic sequences for all choices of the initial data, and lead to sequences
with periods 2, 5 and 8, respectively. In this paper we determine all periodic recursions of the form
where are complex numbers, are non-zero and . We find that, apart from the three recursions listed above, only
lead to periodic sequences (with periods 6 and 8). The non-periodicity of (R) when (or and ) depends on the connection between (R) and the recurrence relations
and
We investigate these recursions together with the related
Each of (A), (B), and (C) leads to periodic sequences if k = 1 (with periods 6, 5, and 9, respectively). Also, for k = 2, (B) leads to periodicity with period 8. However, no other cases give rise to periodicity. We also prove that every real
sequence satisfying any of (A), (B), and (C) must be bounded. As a consequence, we find that for an arbitrary k, every rational sequence satisfying any of (A), (B), and (C) must be periodic.
(Received 27 June 2000; in revised form 5 January 2001) 相似文献
89.
Péter Csóka P. Jean-Jacques Herings László Á. Kóczy 《Mathematical Methods of Operations Research》2011,74(1):41-52
We provide two new characterizations of exact games. First, a game is exact if and only if it is exactly balanced; and second,
a game is exact if and only if it is totally balanced and overbalanced. The condition of exact balancedness is identical to
the one of balancedness, except that one of the balancing weights may be negative, while for overbalancedness one of the balancing
weights is required to be non-positive and no weight is put on the grand coalition. Exact balancedness and overbalancedness
are both easy to formulate conditions with a natural game-theoretic interpretation and are shown to be useful in applications.
Using exact balancedness we show that exact games are convex for the grand coalition and we provide an alternative proof that
the classes of convex and totally exact games coincide. We provide an example of a game that is totally balanced and convex
for the grand coalition, but not exact. Finally we relate classes of balanced, totally balanced, convex for the grand coalition,
exact, totally exact, and convex games to one another. 相似文献
90.
Periodica Mathematica Hungarica - 相似文献