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1.
Juan A. Barceló Jonathan Bennett Alberto Ruiz 《Journal of Fourier Analysis and Applications》2003,9(6):541-562
We study the continuity properties of a projection derived from a recent characterization of Herglotz Wave Functions in the plane. Herglotz Wave Functions are the entire solutions of the Helmholtz equation which have L2-Far-Field-Pattern. The behavior of this projection is reminiscent of the Disc Multiplier Operator on both Lp and mixed Lp-normed spaces. In particular a Kakeya type set plays a central role in our analysis. As a consequence we answer a question posed by Alvarez, Folch-Gabayet and Pérez-Esteva. 相似文献
2.
We consider a new method for producing intensity stabilization of cw lasers. This method incorporates negative feedback from a nonlinear saturable absorber to provide wideband noise-reduction and may produce an output beam for which shot noise is below the quantum limit. This new method can be used with a large variety of cw lasers and is particularly applicable to frequency-stabilized lasers which are locked to absorption lines.Permanent address: Institute of Laser Physics, Novosibirsk 630090, Russia 相似文献
3.
L. G. I. Bennett A. M. C. Harnden B. J. Lewis 《Journal of Radioanalytical and Nuclear Chemistry》1994,180(2):209-216
Normally, gamma-ray spectroscopy is performed by equipment positioned in the SLOWPOKE-2 Facility at the Royal Military College; however, there have occasionally been requirements for analyses externally. A transportable gamma spectroscopy system was thus assembled by acquiring a commercially available multichannel analyzer, analysis program and detector, and by designing and constructing a transportable shielding castle. It was then used to take measurements of fission product concentrations at several research reactors. 相似文献
4.
Curtis Bennett Kathy J. Dempsey Bruce E. Sagan 《Journal of Algebraic Combinatorics》1994,3(3):261-283
We construct a family of partially ordered sets (posets) that are q-analogs of the set partition lattice. They are different from the q-analogs proposed by Dowling [5]. One of the important features of these posets is that their Whitney numbers of the first and second kind are just the q-Stirling numbers of the first and second kind, respectively. One member of this family [4] can be constructed using an interpretation of Milne [9] for S[n, k] as sequences of lines in a vector space over the Galois field F
q. Another member is constructed so as to mirror the partial order in the subspace lattice. 相似文献
5.
本文对广义风险过程中的渐近方差作了非参数估计,得出并证明了两个定理,为广义风险过程中破产概率的区间估计作了理论准备. 相似文献
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Charles H. Bennett 《Foundations of Physics》1986,16(6):585-592
The observed complexity of nature is often attributed to an intrinsic propensity of matter to self-organize under certain (e.g., dissipative) conditions. In order better to understand and test this vague thesis, we define complexity as logical depth, a notion based on algorithmic information and computational time complexity. Informally, logical depth is the number of steps in the deductive or causal path connecting a thing with its plausible origin. We then assess the effects of dissipation, noise, and spatial and other symmetries of the initial conditions and equations of motion on the asymptotic complexity-generating abilities of statistical-mechanical model systems. We concentrate on discrete, spatially-homogeneous, locally-interacting systems such as kinetic Ising models and cellular automata. 相似文献