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991.
H.J.J Seguin 《Optics & Laser Technology》1998,30(5):331-336
An excitation and optical extraction geometry suitable for compact high power gas lasers is described. Multiple slab discharges are established in a diffusion-cooled radial electrode array. Each gain channel is independently driven from a common RF source via a resonant-cavity power distribution system. Radial excitation augmented with multi-channel self-injection phase locking provides stable optical power extraction at good efficiency. The concept is easily scalable to very high powers while dramatically reducing unit size and cost. 相似文献
992.
993.
A telescopic device with charge coupled devices (CCDs) for particle dosimetry in space has been developed. Data on ionization events of energetic particles passing the CCDs are processed in an image analyzing system of a PC. As ‘Charged Particle Telescope’ (CHAPAT), the equipment was flown on the russian space station MIR during the EUROMIR mission in 1995. The response of the CCDs to various charged particles and methods for the discrimination of heavy particles in CCDs are discussed. First results of a correlation of temporal particles fluxes to the actual orbital parameters of MIR clearly identify passages through the South Atlantic Anomaly (SAA). 相似文献
994.
We propose a detailed method for the symmetrization of the standard O(3) or SU(2)⊗CI basis |jτ,m〉 (τ=g or u) into the Oh or Td point group. This is realized by means of an orientation matrix called G. The oriented basis obtained in this way allows matrix element calculations for rovibronic spectroscopic problems concerning octahedral or tetrahedral molecules. Particular attention has been put on careful phase choices. A numerical calculation of all the G matrix elements for both integer and half-integer j values up to 399/2 has been performed. Such high angular momentum values are necessary for the case of heavy molecules with high rotational excitation. To calculate the G coefficients with high precision at high j values we pre-calculated the necessary Wigner functions using symbolic MAPLE software and made then the numerical calculations with quadruple precision. The complete list of these coefficients can be obtained freely at the URL: http://www.u-bourgogne.fr/LPUB/group.html. As an illustration, we also present briefly an application to two typical spectroscopic calculations: the pure rotational levels of SF6 in its ground vibrational state and the ν3 band of ReF6 (an open-shell molecule with an odd number of electrons and a fourfold degenerate electronic ground state). 相似文献
995.
A new generalized version of Aczél’s inequality is proved. This is a unified generalization of some known results. Moreover, the result is applied to the improvement of the well-known Bellman’s inequality. 相似文献
996.
This communication points out a couple of early publications on the power-of-two scheduling scheme that has been consistently ignored by researchers in the past. 相似文献
997.
J.M. Alonso-Meijide B. Casas-Méndez M.J. Holler S. Lorenzo-Freire 《European Journal of Operational Research》2008
Johnston [Johnston, R.J., 1978. On the measurement of power: some reactions to Laver. Environment and Planning A 10, 907–914], Deegan and Packel [Deegan, J., Packel, E.W., 1979. A new index of power for simple n-person games. International Journal of Game Theory 7, 113–123], and Holler [Holler, M.J., 1982. Forming coalitions and measuring voting power. Political Studies 30, 262–271] proposed three power indices for simple games: Johnston index, Deegan–Packel index, and the Public Good Index. In this paper, methods to compute these indices by means of the multilinear extension of the game are presented. Furthermore, a new characterization of the Public Good Index is given. Our methods are applied to two real-world examples taken from the political field. 相似文献
998.
In terms of the so-called irradiance moments of a light field, the beam quality change, ΔQ, of radially and azimuthally polarized beams caused by propagation through a quartic phase plate (as occurs, for example, in strongly pumped laser rods used in high-power solid-state lasers) is studied. Analytical expressions for ΔQ are given, and a comparison between the scalar and vectorial regimes is also shown. The results are applied to several cases of interest. 相似文献
999.
MATLAB仿真技术在电力电子技术实践教学中的应用 总被引:1,自引:0,他引:1
本文以单相半波及三相桥式全波可控整流电路为例,叙述了MATLAB仿真技术在电力电子技术实践教学中的应用。 相似文献
1000.