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91.
有限域上交错矩阵方程解的计数公式及其q超几何级数表达 总被引:1,自引:0,他引:1
设Fq是q元有限域,这里q是任意一个素数p的方幂。本文利用Fq上奇异辛几何给出当A,B分别是阶n秩2v和m秩2s的一般交错矩阵时,Fq上适合方程XAX‘=B的秩k的解X和解X的个数的明显公式,并用q超几何级数简化表达公式。 相似文献
92.
93.
Thomas Kühn Mieczys?aw Masty?o 《Journal of Mathematical Analysis and Applications》2010,369(1):408-1265
We estimate Weyl numbers and eigenvalues of operators via studying their abstract summing norms. In particular we prove estimates of these summing norms for abstract interpolation Lorentz spaces. For this we combine factorization theorems with estimates of concavity constants. Finally we apply our general eigenvalue results to integral operators with kernels of weakly singular type. We obtain asymptotically optimal estimates which extend the well-known classical results. 相似文献
94.
I.L. El-Kalla 《Applied mathematics and computation》2010,217(8):3756-3763
In this paper, we demonstrate that an infinite number of successive integration by parts can be written in a closed form. This closed form can be used directly to prove that the analytic summation of Adomian series becomes identical to the closed form solution for some classes of differential and integral equations. 相似文献
95.
Givenμ, κ, c>0, we consider the functional
defined on allR
n
-valued functionsu on the open subset Ω ofR
n
which are smooth outside a free discontinuity setS
u, on which the tracesu
+,u
− on both sides have equal normal component (i.e.,u has a tangential jump alongS
u).E
Du=Eu − 1/3 (divu)I, withEu denoting the linearized strain tensor.
The functionalF is obtained from the usual strain energy of linearized elasticity by addition of a term (the second integral) which penalizes
the jump discontin uities of the displacement.
The lower semicontinuous envelope
is studied, with respect to theL
1 (Ω;R
n
)-topology, on the spaceP(Ω) of the functions of bounded deformation with distributional divergence inL
2(Ω) (F is extended with value +∞ on the wholeP(Ω)). The following integral representation is proved:
whereϕ is a convex function with linear growth at infinity. NowEu is a measure,ɛ
Du represents the density of the absolutely continuous part of the absolutely continuous part ofE
Du, whileE
s
D
u denotes the singular part and ϕ∞ the recession function ofϕ.
Finally, we show that
coincides with the functional which intervenes in the minimum problem for the displacement in the theory of Hencky’s plasticity
with Tresca’s yield conditions. 相似文献
96.
该文建立了变量核的积分算子的交换子在Herz型空间的CBMO估计. 相似文献
97.
F. Patrone 《Journal of Optimization Theory and Applications》1977,22(3):373-388
We prove an existence theorem for the optimal control of variational inequalities governed by a pseudomonotone operator: the cost is assumed to be quadratic. Then, we give an extension of the theorem to more general costs (assuming the operator to be monotone); we also give a result on a perturbation problem.This work is an extended part of the author's thesis, written under the direction of Professor T. Zolezzi. This research was partially supported by the Consiglio Nazionale delle Ricerche (CNR), Rome, Italy. 相似文献
98.
99.
T R Nelson F D Newman L M Schiffer J D Reith S L Cameron 《Magnetic resonance imaging》1985,3(3):267-273
Fluorine-19 magnetic resonance imaging (MRI) offers advantages for imaging organs and tissues. 19F is readily synthesized into a variety of compounds and offers the potential for in-vivo imaging as a complement to hydrogen MRI. The purpose of this work was to determine the minimum detection sensitivity for a fluorinated compound (CF3-CO2H) as a function of pulse sequence, interpulse times (TE, TI, and TR), gradient values and the number of data averages. CF3-CO2H was chosen because it has a single spectral line and exhibits a minimal frequency shift under the experimental conditions used for this experiment. A resistance MR scanner operating at a resonance frequency of 6.255 MHz was used for imaging both fluorine (.156 T) and hydrogen (.147 T). Critical factors determining the minimum detection sensitivity included system signal-to-noise ratio (S/N), acquisition time, relaxation times (T1, T2), and sample volume. Samples were measured over the range of 0.05 M to 20.0 M and showed a linear relationship between signal strength and concentration. The minimum detection sensitivity was 0.1 M. Use of higher static fields and optimized coils as well as improved system signal-to-noise ratios will improve detection sensitivity. We conclude that imaging of fluorine on low-field system is feasible, although it is necessary to optimize many parameters to maximize detection sensitivity. 相似文献
100.
Takanari Yasui Takeshi Ohtsuka Tetsu Suzuki Shigeki Okajima Kazuya Nakayama Mitsuru Tomioka Katsuhiro Kamimura Takeo Namekata Hiroaki Minamide Hiromasa Ito 《International Journal of Infrared and Millimeter Waves》2006,27(2):199-210
A new, wide-band, high-speed and high-sensitivity THz detector has been developed. The prototype detector consists of a parabolic
cylindrical mirror, a long wire antenna and a Schottky barrier diode. Direct detection measurements have shown a stable sensitivity
of 150 ± 50 V/W for 1–2 THz without any adjustments. The long wire antenna was fixed at the focus of parabolic cylindrical
mirror then it has been realized less operation steps, easy coupling to the external THz signals and a dramatic enhancement
in the practicality of this system. The optically polished mirror and frosted surface one showed comparable sensitivities,
thus easy polishing and less cost mirror fabrication can be applied for this system. The radiation pattern showed a maximum
radiation angle of approximately 23° with its dominant main lobe, which was attributed to the wire antenna character and confirmed
good agreements with classical antenna theory. 相似文献