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101.
面向高性能虚拟网络转发架构及设备VPP,通过重构数据平面的流水线处理模块,设计了基于矢量数据包处理技术的带内网络遥测方案,并在此基础上通过引入源路由机制引导遥测报文走向,实现了一种带内全网遥测的扩展案例.最后,基于虚拟机组网方式,搭建网络拓扑并进行网络性能评测.实验结果表明,该遥测系统能够在0.13 ms精度的遥测时间...  相似文献   
102.
基于传统语音业务利润率下降的现实,阐述了内容服务价值链的形成原因和组成,并提出建设一套能够为电信运营商所用、所管、所利的内容计费平台的必要性.最后,概要说明了内容计费平台的建设原则和两种技术方案与适用条件.  相似文献   
103.
李志勇 《计算物理》2021,38(2):165-170
基于Pin by Pin输运SP3计算是下一代反应堆物理计算方法中一个重要的研究方向.节块法一般采用高阶通量和中子源展开以适应较大的节块尺寸,因此对于Pin by Pin计算来说效率偏低.由于反应堆堆芯不均匀性更多发生在径向,本文提出一种径向基于二维平面通量展开结合轴向常规节块法的综合方法进行三维Pin by Pin输...  相似文献   
104.
Crystallographic planes were detected with X-ray crystal orientation instrument to study wire-cut electrical discharge machining (WEDM) technology for specific crystallographic planes of monocrystalline silicon. The unidirectional conductivity of monocrystalline silicon was analyzed. The contact potential barrier was decreased by preparing Ohmic contact to the surface discharging of the input terminal. Finally, the high-precision discharge cutting of the specific crystallographic planes of monocrystalline silicon was validated. Finished silicon products with specific crystallographic planes were prepared by WEDM, and the cutting efficiency, surface quality, crystal orientation precision, and qualified rate were determined. With cutting thickness of 200 mm, the cutting efficiency reached 100 mm2/min, and the precision of crystal orientation reached 3′ or less.  相似文献   
105.
Fairly accurate approximate expressions for commonly used characteristics of non‐planarity of trigonal sp2‐hybridized centers are reported. It is shown that the behavior of all these parameters as a function of bond angles (α, β, γ) is determined primarily by the square‐root of the difference [360° ? (α + β + γ)]. This quantity is proposed as a new versatile measure of pyramidalization. © 2012 Wiley Periodicals, Inc.  相似文献   
106.
In this paper we present augmented Lagrangians for nonconvex minimization problems with equality constraints. We construct a dual problem with respect to the presented here Lagrangian, give the saddle point optimality conditions and obtain strong duality results. We use these results and modify the subgradient and cutting plane methods for solving the dual problem constructed. Algorithms proposed in this paper have some advantages. We do not use any convexity and differentiability conditions, and show that the dual problem is always concave regardless of properties the primal problem satisfies. The subgradient of the dual function along which its value increases is calculated without solving any additional problem. In contrast with the penalty or multiplier methods, for improving the value of the dual function, one need not to take the penalty like parameter to infinity in the new methods. In both methods the value of the dual function strongly increases at each iteration. In the contrast, by using the primal-dual gap, the proposed algorithms possess a natural stopping criteria. The convergence theorem for the subgradient method is also presented.  相似文献   
107.
The Korteweg-de Vries equation was first derived by Boussinesq and Korteweg and de Vries as a model for long-crested small-amplitude long waves propagating on the surface of water. The same partial differential equation has since arisen as a model for unidirectional propagation of waves in a variety of physical systems. In mathematical studies, consideration has been given principally to pure initial-value problems where the wave profile is imagined to be determined everywhere at a given instant of time and the corresponding solution models the further wave motion. The practical, quantitative use of the Korteweg-de Vries equation and its relatives does not always involve the pure initial-value problem. Instead, initial-boundary-value problems often come to the fore. A natural example arises when modeling the effect in a channel of a wave maker mounted at one end, or in modeling near-shore zone motions generated by waves propagating from deep water. Indeed, the initial-boundary-value problem


studied here arises naturally as a model whenever waves determined at an entry point propagate into a patch of a medium for which disturbances are governed approximately by the Korteweg-de Vries equation. The present essay improves upon earlier work on (0.1) by making use of modern methods for the study of nonlinear dispersive wave equations. Speaking technically, local well-posedness is obtained for initial data in the class for \frac34$"> and boundary data in , whereas global well-posedness is shown to hold for when , and for when . In addition, it is shown that the correspondence that associates to initial data and boundary data the unique solution of (0.1) is analytic. This implies, for example, that solutions may be approximated arbitrarily well by solving a finite number of linear problems.

  相似文献   

108.
Kashin  B. S. 《Mathematical Notes》2002,72(3-4):473-478
In this paper, we establish lower bounds for n-term approximations in the metric of L 2(I 2 ) of characteristic functions of plane convex subsets of the square I 2 with respect to arbitrary orthogonal systems. It is shown that, as n, these bounds cannot decrease more rapidly than .  相似文献   
109.
一种新型单偏振片反射式液晶显示器的设计   总被引:1,自引:1,他引:0  
提出一种新型单偏振片反射式液晶显示器的设计方案。采用共面转换模式并在液晶和反射板之间加入四分之一光延迟膜。通过使用参数空间表示法优化选择器件参数,获得了高反射率、低色散和宽视角的常白、常黑反射式显示模式。  相似文献   
110.
A readout circuit for a 640 × 480 pixels FPA (focal plane array) has been successfully designed, fabricated and tested. The circuit solution is based on a per pixel source-follower direct injection (SFDI) pre-amplifier. Signal multiplexing is performed in both X and Y direction. The pixel size is 25 m × 25m. The chip is optimized for a QWIP (quantum well infrared photodetector) operating at a temperature of 70 K. The circuit has been realized in a standard 0.8 m CMOS process.  相似文献   
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