基于移动Agent的按需路由协议

提出一种新的移动AdHoc网络路由协议——DSR-Ant按需路由协议。该路由协议结合DSR协议与蚁群路由协议的优点,克服其缺点,加入新的路由更新机制。仿真结果显示,DSR-Ant能降低端到端延迟和整个系统的路由发现次数,保持较高的连通性,更适合实时通信。     

基于层次管理的按需路由协议研究

动态源路由（DSR）协议能较好适用中小型对等自组网络环境,但在非对等网络环境中面临一定应用局限。针对该问题,分析DSR协议的特点和存在问题,结合非对等环境和层次路由思想,提出新的协议CDSR,对CDSR路由协议进行性能评估。仿真结果表明,该协议具有较好的执行效能,可提升网络性能。     

MANET路由协议及其性能研究

MANET(Mobile Ad Hoe Network)是由一组无线移动主机组成的一个没有任何建立好的基础设施或集中管理设备的临时网络。网络拓扑易变、带宽、能源有限是Ad Hoc移动网络的主要特点。重点介绍了Ad hoc网络的组网关键技术——路由协议，并对现在的具有代表性的协议性能进行了比较，研究了在不同环境下的各自路由协议仿真实验所体现出来的性能差别，对Ad hoc的组网具有指导意义。     

The electronic booklet on teaching-learning process: Teacher vision and parents of students in primary and secondary education

This article presents the first phase of a research project whose purpose is to introduce a new form of collaboration and communication between the school and the family through an Electronic Booklet (EB). The EB was developed due to the increasing necessity of collaboration between the school and the family, promoting the teaching-learning process and educational success, supported by information and communication technologies. These conclusions and justifications were derived from a survey based in a questionnaire applied to guardians and teachers of several private and public Portuguese schools of the primary and secondary education level. Both groups – guardians and teachers stressed the importance of communication between school and family and expressed interest in the EB as a communication tool. The analysis of the survey results made possible the construction of an Electronics Booklet prototype.     

Investigation of the effects of recycled engine oil bottoms on asphalt field performance following an oxidation modeling approach

This work investigates the effects of recycled engine oil bottoms (REOBs) on asphalt field performance by comparing asphalts with and without REOBs in terms of the asphalt properties required for pavement oxidation modeling. Specifically, oxidation reaction kinetics parameters, dynamic shear rheometer (DSR) function (DSRFn) hardening susceptibility (HS), and low sheer viscosity (LSV) HS are determined and compared for base binder, 5 wt.% REOBs, and 15 wt.% REOBs blends. At the higher percentage, addition of REOBs appears to increase the initial oxidation rate at field temperatures and significantly increases LSV HS, but does not significantly increase the DSRFn HS. A field modeling example elucidates the effects.     

Ad Hoc网络路由协议可扩展性仿真研究

我们利用G1oMoSim仿真工具建立了一个合理的Ad Hoc网络模型,并设计了一个完整的仿真方案对3种Ad Hoc网络路由协议AODV、DSR及DBF进行了全面的性能仿真。通过比较它们的平均报文接收率、平均端到端时延及控制报文的比例得出了AODV协议的可扩展性优于其它两种协议的结论。同时得出了现有的AODV协议同样不适合大规模网络的结论。     

Ad Hoc 网络按需路由协议性能分析

无线移动Ad Hoc网络作为可移动分布式多跳无线网络，没有预先确定的网络拓扑或网络基础设施以及集中控制。为了在这样的网络中促进通信，路由协议主要用于在节点之间发现路径。Ad Hoc网络路由协议的主要目的是网络拓扑的动态变化任意两个节点之间建立一个使得通信总费用和带宽消费最少的正确和有效的通信路径。使用OPNET仿真软件对AODV、DSR协议这两种典型无线移动Ad Hoc网络按需路由协议的参数和性能进行了详细比较和分析。     

ADHOC按需路由协议的仿真与性能分析

介绍了ADHOC网络中路由协议的基本概念和特殊性，引出三种具有典型性的按需路由协议：DSR、AODV、TORA，接下来用OPNET软件对这三种路由协议在不同的网络规模、网络拓扑变化快慢程度下进行仿真，并从路由分组开销、网络时延和分组投递率几个方面进行对比分析论证，得出这3种路由协议在不同场景下的性能特点。     

一种改进Ad hoc网络中TCP性能的方法

由于无线Ad hoc网络拓扑结构的频繁变化以及无线信道的不稳定,导致频繁的路由失效,这给TCP性能带来严重影响。为此对动态源路由协议(Dynamic Source Routing,以下简称DSR)进行了改进。主要包括:通过对链路状态预测估计决定路由上的链路是否进入危险期;使用主动式路由维护机制力争在路由失效前进行快速路由切换。大量仿真实验表明,改进的DSR能有效改善TCP的传输性能,特别是在节点运动频繁的网络中。     

On supporting high-throughput routing metrics in on-demand routing protocols for multi-hop wireless networks

Researchers have proposed routing metrics other than hop count, such as ETX (expected transmission count) and ETT (expected transmission time), to find routes with high throughput. These metrics are inherently suitable to be used in source routing protocols such as DSR, because link state information needs to be collected for the calculation of the shortest path. In this paper, we propose an efficient and generalized approach called accumulated path metric (APM) for supporting high-throughput metrics (HTMs) in on-demand routing protocols. One advantage of APM is that it is able to find the shortest path, in terms of a particular metric, without collecting topology information and without running a shortest-path algorithm. This will significantly simplify the existing design of supporting HTMs in DSR. We present a proof of the correctness of APM. Moreover, we address the problem of duplicate RREQ (route request) transmissions with existing HTM schemes and present a broadcast ordering (BO) technique to suppress unnecessary RREQ transmissions. We study the performance of APM and BO in both AODV and DSR, and the results verify the effectiveness of the proposed approaches.