基于STREAMS机制的IP／X.25软件的设计与实现

ＳＴＲＥＡＭＳ机制是ＵＮＩＸ系统为开发通信服务而提供的一套通用、灵活的开发工具。，ＩＰ／Ｘ．２５软件则是ＴＣＰ／ＩＰ网络与Ｘ．２５公用数据网互连以及通过Ｘ．２５公用数据网实现ＴＣＰ／ＩＰ网络之间的互连的重要途径。文中在介绍基于ＳＴＲＥＡＭＳ机制的通信软件开发的一般思路后，着重叙述了ＩＰ／Ｘ．２５软件的功能和结构以及基于ＳＴＲＥＡＭＳ机制的设计与实现，并对基于ＳＴＲＥＡＭＳ机制的通信软件开发方法作了     

ATM网上TCP传输的拥塞控制算法分析

本文讨论了ＴＣ庆ＡＴＭ网上存在的问题,对三种典型的ＡＢＲ拥塞控制算法;ＥＦＣＩ、ＥＲＩＣＡ和ＦＭＭＡＲＡ在减少信元丢失和传输时延,提高了ＴＣＰ吞吐量等方面的性能进行了分析和并提出了一些在拥塞控制算法中应考虑的问题。     

基于Telnet协议和Clinet／Manager／Server结构综合的信息检索…

本文提出了综合Ｔｅｌｎｅｔ协议和Ｃｌｉｅｎｔ／Ｍａｎａｇｅｒ／Ｓｅｒｖｅｒ结构的网络服务模型；在基于Ｃｌｉｅｎｔ／Ｓｅｒｖｅｒ结构的ＲＤＢＭＳＳＹＢＡＳＥ基础上实现了Ｔｅｎｅｔ协议和Ｃｌｉｅｎｔ／ｍａｎａｇｅｒ／Ｓｅｒｖｅｒ结构综合的图书馆信息检索应用系统，构造了图书馆网络信息服务系统的Ｃｌｉｅｎｔ／Ｍａｎａｇｅｒ／Ｓｅｒｖｅｒ．     

CORBA在网络管理中的应用

洒文介绍了将ＣＯＲＢＡ这种面向对象的分布式计算模型应用于网络管理的方法。着重讨论了ＣＯＲＢＡ应用于ＳＮＭＰ网络管理环境中的静态转换实现方法，并对其特点、结构和实现过程等都进行了详细分析。     

基于TMN逻辑分层的CORBA网管与传统网管互操作机制研究

文章首先介绍了当前网管技术的发展情况,指出分布对象技术是网管的发展方向。但在相当长的时间内,仍是 ＳＮＭＰ、ＣＭＩＰ和 ＣＯＲＢＡ共存的局面。随后针对 ＯＭＧ组织提出的 ＣＯＲＢＡ－ｂａｓｅｄ ＴＭＮ体系,提出了基于 ＴＭＮ逻辑分层的ＣＯＲＢＡ网管与传统网管工操作机制,分析了这种方法的特点及应用情况。     

基于分布式网络的ＳＯＡＰ协议

讨论了ＳＯＡＰ协议的基础,以及它克服现存技术（如ＣＯＲＢＡ和ＤＣＯＭ）的许多缺陷的方法,随后讲述一些ＳＯＡＰ编码规则,并把焦点放在ＳＯＡＰ是怎样映射到存在的ＯＲＰＣ概念上的。     

ATM网上TCP传输的拥塞控制算法分析

本文讨论了ＴＣＰ协议在ＡＴＭ网上存在的问题,对三种典型的ＡＢＲ拥塞控制算法：ＥＦＣＩ、ＥＲＩＣＡ和ＦＭＭＲＡ在减少信元丢失和传输时延、提高ＴＣＰ吞吐量等方面的地分析和比较,并提出了一些在拥塞控制算法中应考虑的问题。     

工业控制网络协议MMP技术的研究与实现

计算机综合制造系统ＣＩＭＳ中最重要的子系统是计算机局部网络，ＭＡＰ则是ＣＩＭＳ系统中计算机局部控制网络的通信协议。本文着重研究ＭｉｎｉＭＡＰ网络技术，通过把目前技术比较成熟的产品（如ＡＲＣＮＥＴ网络）和ＭｉｎｉＭＡＰ协议相结合，实现一种投资省、研制周期快的ＭｉｎｉＭＡＰ网络。     

工业控制网络协议MAP技术的研究与实现

计算机综合制造系统ＣＩＭＳ系统中最重要的子系统是计算机局部网络ＭＡＰ则是ＣＩＭＳ系统中计算机局部网络的通信协议。本文着重研究ＭＡＰ网络技术，通过把目前技术比较成熟的产品（如ＡＲＣＮＥＴ网络）和ＭＡＰ协议相结合，实现一种投资省，研制周期快的ＭｉｎｉＭＡＰ网络。     

综合SNMP和RMON技术实现网络管理

基于ＴＣＰ／ＩＰ网络物简单网络管理协议ＳＮＭＰ已作为事实协议标准被广泛使用。针对ＳＮＭＰ协议实现网络管理的局限性，ＲＭＯＮ标准应运而生。     

A discrete-time analysis of the cyclic reservation multiple access protocol

In this paper a performance analysis of the CRMA (Cyclic Reservation Multiple Access) medium access protocol, which is proposed as an access mechanism for high-speed LANs and MANs is presented. An approximate computational method is derived to obtain the distribution functions of performance measures of interest like the medium access delay and the packet transfer time. The analysis is done in discrete-time domain using a decomposition approach for the access delay in conjunction with a G/G/1 queue with control-feedback and a M/G/1 queue with server vacation. In the model the reservation-cancelation backpressure mechanism is also taken into account. Numerical results are obtained to investigate the efficiency of the backpressure scheme and the scaling issues of the interreserve interval under various load conditions and system configurations. Furthermore, results addressing performance aspects like the fairness issues, the jitter of maximum access delay and the system behavior under station-wise saturated conditions are also discussed.     

A slot reuse scheme for CRMA networks

In the cyclic reservation multiple access (CRMA) scheme, nodes reserve slots in each reserve command. Cycles are then generated in sequence, each of which services the reservations made in the corresponding reserve command. Huang et al. [2,3] proposed a reservation scheme, in which nodes are partitioned into regions and slots can be reused in succeeding regions, to reduce access delays due to long cycles. However, slots cannot be reused by the nodes in the same region, resulting in the waste of available slots and line utilization. We propose a modified scheme to eliminate this disadvantage. As a result, cycles generated are shorter and access delays are smaller.     

一种IPTV动态权限变更系统的研究与实现

本文针对在以大规模接入汇聚路由器(ACR)为核心构成的有线宽带双向接入网络中"静态用户认证状态表"机制不能解决实时授权的问题,提出了基于用户授权信息变更(CoA,Change-of-Authorization)协议的实现方案,该方案不仅能实时更改用户授权,并且具备简单、可扩展、安全等优点.     

多小区OFDMA系统一种跨层资源分配方法

正交频分多址(OFDMA)作为一种新的多址接入方式受到了极大关注.多小区系统由于采用频率复用技术会不可避免的产生小区间干扰,严重影响了多小区无线通信系统的性能,针对多小区OFDMA,提出了一种准分布式跨层资源分配方法.分配方法包括无线网络控制器(RNC)的跨层资源分配算法和基站收发系统(BTS)的跨层资源分配算法.RNC将子信道分配给各个小区的BTS,BTS将分配给该小区的子信道分配给该小区的用户.仿真结果表明,相对于传统的资源分配方法,跨层资源分配方法能有效提高多小区OFDMA系统给定服务质量(QoS)下的吞吐率.     

TD-SCDMA／GSM双网协同中的接通率提升方案

首先基于协议描述了TD-SCDMA／GSM双网协同中的接通率提升方案——FR方案与准FR方案,并阐明各方案所需的系统侧及终端侧改动,在调研基础上给出了目前设备及终端的支持情况,继而总结了实验室及外场测试的结论,并结合LTE中的相关情况创新性地提出了LTE中的FR方案,最后给出了FR方案及准FR方案的应用指导原则。     

Fast and robust face recognition via coding residual map learning based adaptive masking

Robust face recognition (FR) is an active topic in computer vision and biometrics, while face occlusion is one of the most challenging problems for robust FR. Recently, the representation (or coding) based FR schemes with sparse coding coefficients and coding residual have demonstrated good robustness to face occlusion; however, the high complexity of l₁-minimization makes them less useful in practical applications. In this paper we propose a novel coding residual map learning scheme for fast and robust FR based on the fact that occluded pixels usually have higher coding residuals when representing an occluded face image over the non-occluded training samples. A dictionary is learned to code the training samples, and the distribution of coding residuals is computed. Consequently, a residual map is learned to detect the occlusions by adaptive thresholding. Finally the face image is identified by masking the detected occlusion pixels from face representation. Experiments on benchmark databases show that the proposed scheme has much lower time complexity but comparable FR accuracy with other popular approaches.     

SQL Server数据库的简易备份方案

提出了一种适合小型企业的,用Access数据库备份SQL数据库的方案,很好地降低了企业的成本并达到了数据备份的目的。同时,就Access数据库的安全接口作了简略讨论,使备份后不致丧失数据安全性。     

IEEE 802.11 Distributed Coordination Function: Enhancement and analysis

IEEE 802.11 Medium Access Control (MAC) is proposed to support asynchronous and time bounded delivery of radio packets. Distributed Coordination b-kmction (DCF), which uses Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) and binary slotted exponen-tial backoff, is the basis of the 802.11 MAC. This paper proposes a throughput enhancement for DCF by adjusting the Contention Window (CW) setting scheme. Moreover, an analytical model based on Markov chain is introduced to compute the enhanced throughput. The accuracy of the model and the enhancement of the proposed scheme are verified by elaborate simulations.     

Face recognition based on multi-class mapping of Fisher scores

A new hidden Markov model (HMM) based feature generation scheme is proposed for face recognition (FR) in this paper. In this scheme, HMM method is used to model classes of face images. A set of Fisher scores is calculated through partial derivative analysis of the parameters estimated in each HMM. These Fisher scores are further combined with some traditional features such as log-likelihood and appearance based features to form feature vectors that exploit the strengths of both local and holistic features of human face. Linear discriminant analysis (LDA) is then applied to analyze these feature vectors for FR. Performance improvements are observed over stand-alone HMM method and Fisher face method which uses appearance based feature vectors. A further study reveals that, by reducing the number of models involved in the training and testing stages of LDA, the proposed feature generation scheme can maintain very high discriminative power at much lower computational complexity comparing to the traditional HMM based FR system. Experimental results on a public available face database are provided to demonstrate the viability of this scheme.     

Dynamic multiple-frame bandwidth provisioning with fairness and revenue considerations for Broadband Wireless Access Systems

The increasing demand for wireless heterogeneous multimedia services presents a real challenge to mobile network operators. Even with the substantial increase in the supported bandwidth in emerging Broadband Wireless Access Systems (BWASs) such as 3.5G High Speed Downlink Packet Access (HSDPA) and the Worldwide Interoperability for Microwave Access (WiMAX), satisfying the bandwidth requirements of mobile users while increasing the revenues of network operators is still one of the major issues in these systems. Therefore, bandwidth provisioning will certainly play a decisive role in the success of such BWASs. In this paper, we propose a novel dynamic multiple-frame bandwidth provisioning scheme for BWASs. The proposed scheme spans multiple time frames and optimally allocates them to the different classes of traffic depending on their weights, the real-time bandwidth requirements of their users’ connections, their channel quality conditions and the expected obtained revenues. To maximize fairness and still maintain service differentiation between classes, we provide a unique formulation for dynamically computing the class weights. Simulation results are provided to show the potential and effectiveness of our scheme.