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81.
Oscillating nature of current pulses under d.c. excitation in subnormal region with longitudinal magnetic field at pressure
range 0.20 torr to 0.85 torr have been studied. The frequency, bandwidth, peak-peak voltage, cut-off current and rise time
of the current pulses have been observed with pressure, average tube current and magnetic field. A study of these oscillograms
in magnetic field, average tube current and pressure are presented. The probable mechanism for the generation of oscillation
based on space-charge field modification with magnetic field is discussed 相似文献
82.
A generalisation of the Burg algorithm to vector spaces is described. This can be used to subsample time series that have narrow frequency bandwidth, thereby reducing the computation time and the complexity of the autoregressive model required. The technique is preferable to conventional subsampling. 相似文献
83.
84.
Ioannis D. Moscholios Michael D. Logothetis 《International Journal of Communication Systems》2006,19(1):67-93
We consider a single link loss system of quasi‐random input, described by the Engset multirate loss model (EnMLM). Blocked calls may once reattempt to be connected to the system requiring less bandwidth; then the system is described by the single retry model for finite sources (f‐SRM). The EnMLM and the f‐SRM are extended with the single threshold finite source model (f‐STM), where calls may attempt to be connected to the system with less bandwidth requirements, according to the link occupancy, before blocking occurs. We focus on CBP equalization in the EnMLM, f‐SRM and f‐STM, under the bandwidth reservation (BR) policy. For this analysis, we apply two approximate methods, the Roberts' method and the method of reverse transition rates (RTR), which lead to a recursive CBP calculation. We evaluate the accuracy of the above models under the BR policy by comparing the analytical with simulation CBP results, based on the relative approximation errors (RAE). The results are highly satisfactory because they show that the proposed models (formulas) lead to small RAE. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
85.
研究了在美国BNL/AGS上能量10.7AGeV的197Au离子诱发核作用,报告了EMU–01国际合作实验关于射弹核碎裂和产生粒子密度等最新实验结果. 相似文献
86.
A new flow electrical conductance instrument was constructed and tested on dilute NaCl solutions up to 458 K, and on more
concentrated solutions (maximum 0.436 mol⋅kg−1) at 373 K. The results of the new instrument agreed with those of previous authors within the estimated experimental errors.
The model of Bernard et al. (J. Phys. Chem. 96, 3833–3840 (1992), MSA) was found to represent the high-temperature results without introducing an ion-pairing equilibrium constant. The Fuoss–Hsia
conductance equation as given by Fernandez-Prini was found to represent the dilute concentrations with Λ° (NaCl) as the only adjustable parameter. It was found that Λ° (NaCl) could be expressed as a function of solvent viscosity and density by using three parameters found by regression of
literature results between 278.15 and 523 K. This equation along with the FHFP theory permits the equivalent conductivity
of dilute sodium chloride solutions to be calculated within the accuracy of the existing experimental measurements. 相似文献
87.
高密度氩气的原子间相互作用与状态方程 总被引:5,自引:4,他引:1
本文从高密度气体的原子间相互作用出发进行思考,在修改范德瓦耳方程的基础上,提出了一种新的适用于高密度气体的状态方程,并用以对氩气临界区的等温压缩线进行计算,结果与实验值很符合. 相似文献
88.
高功率二极管泵浦固体激光技术和应用前景的分析 总被引:2,自引:1,他引:1
文章对高功率二极管泵浦固体激光器的若干关键技术,包括激光二极管和增益介质,泵浦,耦合和冷却技术,以及光学谐振腔等作了详细的分析。 相似文献
89.
High temperature scanning tunneling spectroscopy (HT-STS) was used to investigate the electronic structure of Au(1 1 1) at different temperatures in the energy range 0-1 eV below the Fermi level. We concentrated on the influence of temperature on the Shockley surface state (SS) appearing on noble metals surface due to a surface projected bulk bang gap in [1 1 1] direction. The influence of temperature on the projected band gap edge (BE) was also investigated. The experiment was carried out in the temperature range 294-580 K. As the result of the experiment a delicate shift of the SS and the BE in direction of the Fermi level was reported. 相似文献
90.
High temperature oxidation of metals leads to residual stresses in the metal and in the oxide. In this work, we try to predict the evolution of the residual stresses in the growing oxides layers, during isothermal oxidation. The origin of these stresses is based on the microstructural model of Clarke, however, another justification is proposed, assuming a proportional dependence of the growth strain with the oxide layer thickness. Using the mechanics of thin layers, as well as the analysis proposed to describe the growth strain, a system of equations are deduced that predict the stresses evolution with oxidation time. Numerical analysis is performed, leading to a set of theoretical curves. 相似文献