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941.
In this paper, we review and unify some classes of generalized convex functions introduced by different authors to prove minimax results in infinite-dimensional spaces and show the relations between these classes. We list also for the most general class already introduced by Jeyakumar (Ref. 1) an elementary proof of a minimax result. The proof of this result uses only a finite-dimensional separa- tion theorem; although this minimax result was already presented by Neumann (Ref. 2) and independently by Jeyakumar (Ref. 1), we believe that the present proof is shorter and more transparent. 相似文献
942.
The object of the present investigation is to introduce a new trigonometric method of summation which is both regular and
Fourier effective and determine its status with reference to other methods of summation (see §2-§4) and also give an application
of this method to determine the degree of approximation in a new Banach space of functions conceived as a generalized Holder
metric (see §5). 相似文献
943.
Eremenko L. T. Oreshko G. V. Nesterenko D. A. Lagodzinskaya G. V. Eremenko I. L. 《Russian Chemical Bulletin》2002,51(1):157-159
The reactions of ethylene glycol mononitrate and glycerol 1,3-dinitrate with methylphosphonic dichloride afforded new nitroxyalkyl methylphosphonates. 相似文献
944.
Electron-positron pair production cross sections are calculated for 50-MeV electrons incident on an oxygen nucleus. The symmetric coplanar cross sections are emphasized. Neglecting exchange, the spectra of forward-scattered projectile electrons is numerically calculated. In the extreme relativistic and nonrelativistic limits for the produced pair kinetic energies, calculated cross sections are similar to those of Bhabha. 相似文献
945.
N. L. Vekshin 《Journal of Applied Spectroscopy》1991,54(1):17-22
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 54, No. 1, pp. 26–32, January, 1991. 相似文献
946.
Summary We investigate the transition from two-frequency quasiperiodicity to chaotic behavior in a model for a quasiperiodically driven
magnetoelastic ribbon. The model system is a two-frequency parametrically driven Duffing oscillator. As a driving parameter
is increased, the route to chaos takes place in four distinct stages. The first stage is a torus-doubling bifurcation. The
second stage is a transition from the doubled torus to a strange nonchaotic attractor. The third stage is a transition from
the strange nonchaotic attractor to a geometrically similar chaotic attractor. The final stage is a hard transition to a much
larger chaotic attractor. This latter transition arises as the result of acrisis, the characterization of which is one of our primary concerns. Numerical evidence is given to indicate that the crisis arises
from the collision of the chaotic attractor with the stable manifold of a saddle torus. Intermittent bursting behavior is
present after the crisis with the mean time between bursts scaling as a power law in the distance from the critical control
parameter; τ ∼ (A-Ac)-α. The critical exponent is computed numerically, yielding the value α=1.03±0.01. Theoretical justification is given for the
computed critical exponent. Finally, a Melnikov analysis is performed, yielding an expression for transverse crossings of
the stable and unstable manifolds of the crisis-initiating saddle torus. 相似文献
947.
948.
B. A. Usievich D. Kh. Nurligareev V. A. Sychugov K. M. Golant 《Optics and Spectroscopy》2006,101(6):930-934
A system of tunnel-coupled rectilinear waveguides is studied. The dependence of the number of modes in this system on the number of waveguides N, the distance between the waveguides, and the number of modes in a separate waveguide is considered. It is shown that the modes of the m = N and N + 1 orders in such a system are Bragg modes; i.e., the angle between the direction of their propagation and the system axis is close to the Bragg angle. The effective refractive indices n * of these modes change stepwise. The step size Δn * is found to be dependent on the distance s between the waveguides and on the number of modes in a separate waveguide. A system of single-mode waveguides with the number of guided modes M = 34 < N = 50 is studied experimentally. It is shown that the Bragg modes of the system lie among the leakage modes of the system and have rather low losses. It is demonstrated that the localization of the Bragg modes among the leakage modes may be favorable for their selection upon light generation. 相似文献
949.
Kirk L. Shanahan 《Thermochimica Acta》2006,441(2):210-214
Dr. E. Storms has published a Letter [E. Storms, Comment on papers by K. Shanahan that propose to explain anomalous heat generated by cold fusion, Thermochim. Acta, 2006] in which he argues that in a sequence of recent papers, the apparent excess heat signal claimed by Dr. Shanahan to arise from a calibration constant shift is actually true excess heat. In particular he proposes that the mechanisms proposed that foster the proposed calibration constant shifts cannot occur as postulated for several reasons. As well, he proposes Shanahan has ignored the extant data proving this. Because this Letter may lend unwarranted support to acceptance of cold fusion claims, these erroneous arguments used by Storms need to be answered. 相似文献
950.
Water suppression by diffusive attenuation was used to measure Brix in intact cellular tissue of apple and strawberry. Given
the signal-to-noise ratio, the correlation for apple was established without repeated acquisition, so this protocol should
also be useful for rapid, on-line measurements at low spectrometer frequencies. Water suppression by theT
1-Null method fails with cellular tissue because of the considerable variation in the longitudinal relaxation times of vacuolar
and cytoplasmic water. 相似文献