互联星空业务支撑系统浅析

首先介绍了互联星空业务特点，对整个业务的关键技术——认证授权、计费、结算等实现过程进行了详细描述，最后给出了互联星空发展需要进一步考虑的问题。     

类型强制:一种新的安全模型

首先介绍类型强制的原理,然后介绍一种纳入类型强制机制的防火墙Sidewinder。     

一种基于HINOC网络动态带宽分配新算法的实现

本文提出一种新型的HINOC动态带宽分配算法,利用令牌桶给各个HM分配令牌,在每个MAP周期都重新进行一次计算,以分配在本MAP周期内HM所需发送的令牌数,并按比例进行截断依次来对HM的数据进行均衡。这样将最大程度的合理分配每个HM的数据发送时间,即保证每个HM分配带宽的公平性又能有效的降低发送时延。     

一种面向会展中心的无线自组网MAC层协议的设计

文中研究了无线令牌环协议,将MAC层的WTRP协议应用于无线自组网中,采用WTRP协议优化了会展企业中心无线自组织网络.重点介绍了WTRP协议的状态机以及控制机制,模型中的节点通过令牌获得网络的使用权,而令牌在节点之间传递,并以公平和效率为原则.网络仅需要时令牌进行管理和维护,而不需要对网络中的数据进行管理,使得数据在网络中进行透明的传输,增加了网络的保密性.通过仿真验证了模型的正确性,减少了数据包在网络节点中的等待时间,使得会展企业活动越来越便捷.     

基于“桶中能量法”的相位共轭保真度测量研究

 给出了基于“桶中能量法”的相位共轭保真度测量原理、方法与结果。通过对适当大小的空间滤波针孔能量透过率的直接测量可以得到相位共轭保真度并简单实现系数 标定, 给出了针孔大小的选择原则、系数标定方法和共轭保真度的计算公式以及单池受激 布里渊散射相位共轭镜在几种条件下的实验结果, 指明了这种方法的重要性与不足之处。     

ATM网中标准UPC算法及其实现

本文介绍了ＡＴＭ网络中用户参数控制的策略，着重讨论了两种标准的峰值信元速率控制算法，提出了可能的电路实现方案，并分析了用户参数控制策略与业务性能的关系。     

ATM网络双速漏桶监管算法

本文提出一种ＡＴＭ网络监管新算法———双速漏桶算法。对它的性能进行理论分析和计算机模拟，并探讨其硬件实现的可能性和复杂性。结果表明：在硬件复杂性基本不增加情况下，双速漏桶监管法比单速漏桶算法在监管选择性、信元丢失率及信元等待时间等性能方面有较大改善。     

On effects of arrival rate and burstiness in the queueing system: Analysis ofLb/D/1

This paper studies a single-server queueing system with deterministic service time in which arrivals are regulated by the leaky-bucket mechanism. This paper intends to improve quantitative understanding of the effects of arrival rate and burstiness on the average delay of queueing systems. The study is directed toward identifying the worst traffic of arrivals allowed by the leaky-bucket regulation and clarifying the effects of the leaky bucket parameters (which represent the arrival rate and burstiness) on the average queueing delay. The arrival traffic that maximizes the average queueing delay is characterized as the repetition of the following three phases: bulky arrival, greedy arrival for a specified length of interval, and then no arrival till the token bucket is full. The average queueing delay for the worst traffic is expressed as a function the leaky bucket parameters.Research was partially supported by the NSF under grant ECS-8552419. Research was conducted at the Laboratory for Information and Decision Systems of the Massachusetts Institute of Technology and the U.S. Naval Research Laboratory.     

Propagation characteristics of the Yb-doped fiber lasers after spectral beam combining by the VBGs

The propagation model for the spectral beam combining system of five Yb-doped fiber laser beams by the volume Bragg gratings (VBGs) has been built up. Considering the surface distortion by thermal effect, the intensity of an individual beam passing through the spectral beam combining system by the VBGs with deformation has been analyzed numerically and iteratively by using finite-different and sparse matrix methods, and the intensity of combined beam has been studied by the principle of incoherent superposition. Consequently, according to the intensity second-order moments method, the M²-factor of the combined beam has been calculated. The effects of deformation of the VBGs on the intensity, the combining efficiency, the M²-factor and the power in the bucket of the combined beam have been analyzed quantitatively. It can be shown that the effects of the deformation of the VBGs on the intensity distribution of combined beam become more and more obvious with the increasing of the deformation of the VBGs. The results show that the surface distortion of the VBGs due to high-power lasers dramatically degrades both the beam quality of the combined beam and the combining efficiency of the spectral beam combining system.