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91.
Nguyen H. V. Hu'ng 《Transactions of the American Mathematical Society》2001,353(11):4447-4460
Let be Singer's invariant-theoretic model of the dual of the lambda algebra with , where denotes the mod 2 Steenrod algebra. We prove that the inclusion of the Dickson algebra, , into is a chain-level representation of the Lannes-Zarati dual homomorphism
The Lannes-Zarati homomorphisms themselves, , correspond to an associated graded of the Hurewicz map
Based on this result, we discuss some algebraic versions of the classical conjecture on spherical classes, which states that Only Hopf invariant one and Kervaire invariant one classes are detected by the Hurewicz homomorphism. One of these algebraic conjectures predicts that every Dickson element, i.e. element in , of positive degree represents the homology class in for 2$">.
We also show that factors through , where denotes the differential of . Therefore, the problem of determining should be of interest.
92.
M. Yu. Doladov V. S. Kazakevich I. G. Kalashnikov V. V. Kupaeva V. A. Shcherbakov 《Journal of Applied Spectroscopy》2001,68(4):708-710
The results of an investigation of the reflection spectrum of the human tympanic membrane in the visible and near IR ranges ( = 400–900 nm) are reported. 相似文献
93.
Suppose that { f(n), n N
0
} is a sequence of positive real numbers and suppose that the sequence { a(n), n N
0
} is given by a(0) = 0, and, for n 1, by the convolution equation nf(n) = a* f(n). The resulting sequence is denoted by a(n) =
f
(n) and is called the De Pril transform of { f(n), n N
0
} . In this paper, we consider first- and second-order asymptotic behavior of {
f
(n), n N
0
} for a large class of subexponential sequences { f(n), n N
0
} . We also discuss some applications. 相似文献
94.
Fernando Mayoral 《Proceedings of the American Mathematical Society》2001,129(1):79-82
We characterize the compactness of a subset of compact operators between Banach spaces when the domain space does not have a copy of
95.
Consider the stochastic partial differential equationdu
(t,x) = (t)u
(t, x)dt + dW
Q(t,x), 0 t T
where = 2/x
2, and is a class of positive valued functions. We obtain an estimator for the linear multiplier (t) and establish the consistency, rate of convergence and asymptotic normality of this estimator as 0. 相似文献
96.
Suthep Suantai 《Southeast Asian Bulletin of Mathematics》2000,24(2):297-303
In this paper, we give necessary and sufficient conditions for infinite matrices mapping from the Nakano vector-valued sequence space (X, p) into any BK-space, and by using this result, we obtain the matrix characterizations from (X, p) into the sequence spaces (Y), c0(Y, q), c(Y), s(Y), Er(Y), and Fr(Y), where p = (pk) and q = (qk) are bounded sequences of positive real numbers such that pk 1 for all k N, r 0, and s 1.AMS Subject Classification (2000): 46A45 相似文献
97.
The method of quasilinearization is a procedure for obtaining approximate solutions of differential equations. In this paper, this technique is applied to a differential-algebraic problem. Under some natural assumptions, monotone sequences converge quadratically to a unique solution of our problem. 相似文献
98.
We study rate of convergence in the strong law of large numbers for finite and infinite variance time series in both contexts of weak and strong dependence. 相似文献
99.
Ragheb M. Abu-Sarris 《Journal of Computational Analysis and Applications》2000,2(1):103-109
In this paper, we are concerned with the global behavior ofthe solutions of the difference equation
where
and
. Necessary and sufficient conditions for boundedness, persistence,and periodicity of all solutions will be established. The oscillatorybehavior will be investigated. 相似文献
100.
Q. Md. Alfred T. Chakravarty G. Singh S. K. Sanyal 《International Journal of Infrared and Millimeter Waves》2007,28(10):881-887
In radar, planar phased array antenna plays vital role in electronic scanning in the azimuth and elevation direction to the
horizon. In most operations using planar phased array both the coordinates of azimuth and elevation, are steered electronically.
In this paper a conceptual schematic of a phased array antenna with programmable time delay units has been presented. It is
shown that by suitably exploiting the time delay matrix one can have electronic beam rotation around the target axis as required
in conical scan. Thus both the elevation and azimuth motors in conical scan system are replaced by electronic scanning. Heuristically,
we have selected eight consecutive points for beam rotation in a polygon shape and can also be extended almost circular shape
by increasing number of array elements and phase shifter (delays) in the delay matrix. The array requires dual control of
phase gradient and individual phase values. The whole array is controlled by micro-controller. This presents exciting possibilities
in radar operation. 相似文献