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811.
The aim of this paper is to highlight the added value of the generalized Gouy phase shift introduced by Siegman. Although suited for optical systems study, including those more complex than free space, we note that it did not meet the use that it deserves so far. The analysis of the whole of the ideas and analytical approaches associated to the important concept of the Gouy phase proves its effectiveness.
Usually, the resonance condition is systematically built on the basis of the equivalent empty cavity. Unfortunately, this approach does not cover some of the useful parameters of the real resonator. By means of the generalized Gouy phase and the self-consistent complex parameter q, we derive here a new approach for the calculation of the resonance condition for the real cavity. Moreover, the use of the generalized Gouy phase clearly simplifies the study of resonators, while making it possible to avoid the use of the Huygens’ Fresnel integral. 相似文献
812.
I. P. Raevskii L. A. Reznichenko M. P. Ivliev V. G. Smotrakov V. V. Eremkin M. A. Malitskaya L. A. Shilkina S. I. Shevtsova A. V. Borodin 《Crystallography Reports》2003,48(3):486-490
(Na, K)NbO3 crystals with a perovskite structure and a KNbO3 content up to 40 mol % were grown from flux with the use of the solvent NaBO2. The dielectric measurements of the crystals grown revealed phase transitions that had never been observed before in ceramic samples. 相似文献
813.
814.
K A Dowsland M Gilbert G Kendall 《The Journal of the Operational Research Society》2007,58(4):429-438
This paper is concerned with the development of a customized circle packing algorithm for a manufacturer of sprockets for the motor cycle industry. Practical constraints mean that the problem differs somewhat from those tackled elsewhere in the literature. In particular, the layouts need to conform to a given structure. This is achieved by using a local search algorithm with an appropriate starting solution and a series of neighbourhoods designed to preserve the layout structure. Empirical evidence based on real data shows that the quality of the resulting solutions closely matches that of cutting patterns currently produced by human experts. Computation times average around 20–30?s per order as compared to several hours for an equivalent manual solution. 相似文献
815.
We consider the method of Poincaré to investigate thelocal index of vector fields in the plane. If m is the degreeof the first non-zero jet, Xm, of the vector field X at an isolatedzero, we explore the geometry of the pencil generated by thecoordinate functions of Xm when the absolute value of the indexof X, |ind (X)|, is m. We also find necessary and sufficientconditions for |ind (X)| to be m. 相似文献
816.
A. V. Gavrilov 《Siberian Mathematical Journal》2007,48(1):56-61
We study the double exponential map which is a composition of a special form of two exponential maps on a manifold with connection. We relate this map and the composition of covariant derivations as well as the composition of pseudodifferential operators on these manifolds. 相似文献
817.
818.
B. Sun Yu. A. Litvinov P. M. Walker K. Beckert P. Beller F. Bosch D. Boutin C. Brandau L. Chen C. Dimopoulou H. Geissel R. Knöbel C. Kozhuharov J. Kurcewicz S. A. Litvinov M. Mazzocco J. Meng C. Nociforo F. Nolden W. R. Plass C. Scheidenberger M. Steck H. Weick M. Winkler 《The European Physical Journal A - Hadrons and Nuclei》2007,31(3):393-394
A new long-lived isomeric state in the near proton dripline nucleus 125Ce has been identified with Schottky mass spectrometry at GSI. The excitation energy E
* = 103(12)keV and the decay time of 193(1)s have been obtained from a single stored fully ionized 125m
Ce58+ ion. The data implies an E3 transition and a 1/2+ assignment for the spin of the isomer. 相似文献
819.
820.
The equation of sound propagation in an unstable medium produced by the presence of supersaturated water vapor in it, which
can appear in a hurricane area, is derived. This equation takes into account the effects of sound velocity dispersion, amplification,
damping, and nonlinear effects. Some solutions to this equation are presented, illustrating the specific features of sound
propagation in an unstable medium.
Published in Akusticheskiĭ Zhurnal, 2007, Vol. 53, No. 3, pp. 477–480. 相似文献