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991.
本文首先探讨了下一代固网、移动网、IP网将发生的变化,如固网智能化改造、软交换引入等,然后通过分析下一代固网、移动网和IP网对传输网的需求,指出了下一代传输网所面临的挑战,探讨了ASON在下一代网络中的定位和发展前景. 相似文献
992.
993.
A Policy-based Approach for Reconfiguration Management and Enforcement in Autonomic Communication Systems 总被引:1,自引:0,他引:1
This paper presents an overview of the policy-based reconfiguration management and enforcement for autonomic communication
system platform (Pre-meacs). In contrast to existing management approaches, which require static priori policy configurations,
policies are created dynamically. The proposed Pre-meacs framework creates new policies at runtime in response to the changing
requirements. A hierarchical policy model is used to refine users and administrators’ high-level goals into low-level objectives.
The new approach ensures the success of the reconfiguration through monitoring feedback. The main components of Pre-meacs
framework for policy creation, storage, evaluation and enforcement are presented, and the procedures of Pre-meacs in networks
reconfiguration management are also demonstrated. Illustrative example demonstrates the performance of the proposed framework.
相似文献
Jie ChenEmail: |
994.
Xiang Zhu D.T. Cassidy M.J. Hamp D.A. Thompson B.J. Robinson Q.C. Zhao M. Davies 《Photonics Technology Letters, IEEE》1997,9(9):1202-1204
InGaAsP-InP strained multiple-quantum-well (MQW) lasers for extended wavelength tunability in external cavity operation were designed, fabricated, and tested. The active layer was a strain compensated structure consisting of three 3.2/spl plusmn/0.3 nm and three 6.4/spl plusmn/0.3 nm 1.0% compressive strained wells and five 10.3/spl plusmn/0.3 nm 0.45% tensile strained barrier layers. A 2-/spl mu/m-wide ridge waveguide laser of length 250 /spl mu/m, when used in a grating external cavity and with no coatings to alter the reflectivity of the facets, was observed to operate over a range >110 nm. The lasers were designed for applications in trace gas and liquid detection with the goal to maximize the tunable range when operated in external cavities and with no facet coatings. 相似文献
995.
该文提出了一种基于有限容量缓冲区下CBR业务信元丢失率和最小速率替换的线性近似连接允许控制机制,与原有的CAC机制相比,该文的CAC机制存在两个方面的改进:一方面,使用更合理、精确的CLR表达式,从而能够作出更为准确的连接允许判断:另一方面,能够提供服务质量服务。 相似文献
996.
The gain and the tuning characteristics of miniature optically pumped super-radiant NH3 submillimeter-wave gas laser have been studied theoretically based on the quantum density matrix equations. The density matrix equations of three-level quantum system have been solved, and the gain and the output density versus different frequency detuning of submillimeter laser and infrared pumping laser have been calculated respectively by means of iteration method. The characteristic curves corresponding to ideal monochromatic IR pumping model and broadened IR pumping model have been obtained. Meanwhile, the tuning and the nonlinear properties of the system have been revealed. 相似文献
997.
D. L. Hibbard R. W. Chuang Y. S. Zhao C. L. Jensen H. P. Lee Z. J. Dong R. Shih M. Bremser 《Journal of Electronic Materials》2000,29(3):291-296
In this paper, we describe the change in barrier heights (ϕB) and ideality factors (n) of Ni/Au contacts to p-GaN determined from current-voltage measurements as a result of (a) rapid
thermal annealing between 400–700°C under flowing nitrogen, and (b) testing at temperatures of 20–300°C. The lowest barrier
height and ideality factor values were obtained from samples annealed at 500–600°C. These results provide supporting evidence
that thermal processing helps to remove contaminants at the contact-GaN interface, thus decreasing effective barrier height
and consequently, contact resistance. 相似文献
998.
1.概述 随着信息化高速发展和高科技时代的到来,恶意软件和非法内容也随之增多,危害严重的蠕虫等恶意代码能够在短时间内传遍全球,感染上万台主机,并造成无法估量的经济损失、数据丢失,同时还会大量消耗网络和系统修复的时间、人力成本. 相似文献
999.
The simulation software, HFSS (high frequency structure simulator), is introduced in microwave oven design. In the cold test, a network analyzer is used to measure the reflection coefficient (S11) of the cavity under empty and loaded states over the frequency range from 2.448 GHz to 2.468 GHz. In the hot test, a piece of wet thermal paper and an infrared thermal imaging camera are used to measure the electric field distributions on the mica and turntable. In the cold test, the simulation agrees well with the experiment no matter in empty state or loaded state. In the hot test, the simulation agrees well with the experiment in general in empty state and approximately in loaded state. The little difference in both cold and hot test may be due to that the model in simulation is not absolutely identical with that in experiment or the inadequate precision of infrared thermal imaging camera. 相似文献
1000.