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891.
Production and amplification of radially and azimuthally (tangentially) polarized laser beams are demonstrated. Based on the different focusing between radially and tangentially polarized light in thermally stressed isotropic laser rods, Nd:YAG laser oscillators were developed to produce low-loss stable oscillation in a single polarization. Pure radially polarized light at 70 W with M2 = 2 and on-axis impure radially polarized light at 150 W with M2 = 2.5 were achieved. The radially polarized beams were then amplified while good beam quality and polarization purity were retained. Complete elimination of thermal-birefringence-induced aberrations was demonstrated. This should allow much better beam quality from rod-based high-power lasers. 相似文献
892.
We study under what condition there exists a solution of
-u+f(u)=0 in a
domain which blows-up on the boundary, independently of the regularity of the boundary,
and we provide criteria for uniqueness. We apply our results to the case
f(u)=
eau. 相似文献
893.
Yossi Moshe 《Journal of Number Theory》2003,103(1):109-121
Let be a double sequence over a finite field satisfying a linear recurrence with constant coefficients, with at most finitely many nonzero elements on each row. Given a nonzero element g of , we show how to obtain an explicit formula for the number of g's in the first qn rows of A. We also characterize the cases when the density of 0's is 1. 相似文献
894.
Moshe Sniedovich 《The Journal of the Operational Research Society》1980,31(11):1025-1032
A preference order dynamic programming model proposed in the literature for solving stochastic knapsack problems is shown to be somewhat limited from both the methodological and computational points of view. A counterexample is presented contradicting the optimality of a procedure designed for normal variates. 相似文献
895.
We show that the notion ofHZ-local groups due to A. Bousfield which is based on considerations from algebraic topology can be defined and understood in
terms of solubility of certain systems of equations overG. 相似文献
896.
897.
Dedicated to Professor Shmuel Agmon 相似文献
898.
Moshe Dubiner 《Integral Equations and Operator Theory》1991,14(3):359-372
We will prove that the normalized product of a convergent sequence of matrices transforms most vectors into the subspace of generalized eigenvectors with eigenvalues of maximal absolute value. 相似文献
899.
We discuss diffractive production in the context of two-component models. After defining the class of models that we consider and discussing their general properties, we develop integral equations for the generating functions of diffractive processes. We consider single and double diffraction and two fireball production. We investigate the behavior of the partial cross sections for n-particle production in all three cases and obtain a successful fit to recent data. 相似文献
900.
F. Paul Wyman William M. Orr Jr. 《The Journal of the Operational Research Society》1973,24(4):593-601
This paper develops a near optimal policy for opening a second counter in a quick-service restaurant when n persons are in the first line, given that the arrival process is cyclic rather than purely stationary. A simulation was written in GPSS which permitted the use of different arrival generators during different time segments of the simulated day. Results indicate that as n is varied, waiting time and utilization levels exhibit an S-shaped curve between the pure 1 facility and the 2 facility cases. Results also indicate that a cyclic arrival process greatly increases (relative to the case of exponential arrivals) mean waiting time, facility utilization, and the range of n. Finding the optimal (least cost) value of n is illustrated for cases in which costs of customer waiting time can be meaningfully imputed. 相似文献