Experimentation on end-to-end performance aware algorithms in the federated environment of the heterogeneous PlanetLab and NITOS testbeds

The constantly increasing diversity of the infrastructure used to deliver Internet services to the end user has created a demand for experimental network facilities featuring heterogeneous resources. Therefore, federation of existing network testbeds has been identified as a key goal in the testbed community, leading to a recent activity burst in this research field. In this paper, we present a federation scheme that was built during the Onelab 2 EU project. This scheme federates the NITOS wireless testbed with the wired PlanetLab Europe testbed, allowing researchers to access and use heterogeneous experimental facilities under an integrated environment. The usefulness of the resulting federated facility is demonstrated through the testing of an implemented end-to-end delay aware association scheme proposed for wireless mesh networks. We present extensive experiments under both wired congestion and wireless channel contention conditions that demonstrate the effectiveness of the proposed approach in realistic settings. The experiments are also reproduced in a well-established network simulator and a comparative study between the results obtained in the realistic and simulated environments is presented. Both the architectural building blocks that enable the federation of the testbeds and the execution of the experiment on combined resources, as well as the important insights obtained from the experimental results are described and analyzed, pointing out the importance of integrated experimental facilities for the design and development of the Future Internet.     

城市边缘活力的再生——解读澳大利亚墨尔本联邦广场

介绍了由实验建筑工作室主持设计的澳大利亚联邦广场项目。通过分析其项目选址、功能布局和空间特征,指出该项目通过改善城市结构、引入多功能性的建筑群体和运用自由的空间构成手法以促进城市边缘活力的再生。     

HLA联邦开发执行过程及发展趋势

对高层体系结构（HLA）的组成、最新发展的联邦开发执行过程（FEDEP）和支撑软件进行了详细的介绍,给出了联邦开发执行过程的发展趋势,并对我国开展这方面的研究提出了方向和目标。     

一种基于移动Agent的RTI通信机制研究

该文针对目前RTI通信机制存在的通信效率低、系统可重用性差等问题,提出了一种基于移动Agent的RTI通信机制。该通信机制采用人工智能技术,使仿真中数据交互过程由“别人提供”变为“自己提取”模式,简化了联邦成员间的数据交互协议,提高了联邦成员的可重用性和相对独立性。该文还给出了移动Agent的实现策略,提出在通用移动A-gent的基础上构造通信移动Agent的思路。     

Model‐based code generation for HLA federates

This paper addresses the problem of automated code generation for a High Level Architecture compliant federate application given its behavior model. The behavior model is a part of the architectural model of a federation that the federate can participate in. The federate behavior model is based on Live Sequence Charts, adopted as the behavioral specification formalism in the Federation Architecture Metamodel (FAMM). FAMM serves as a formal language for describing federation architectures. An objective is to help the testing of federation architecture by means of its prototype implementation early in the development lifecycle. A further objective is to help developers construct complete federate applications that are well modularized. The approach to achieve these objectives is aspect‐oriented in that the generated code, which handles the federate's interactions with a federation execution, serves as the base code, where the computation logic is to be weaved as an aspect. Copyright © 2009 John Wiley & Sons, Ltd.     

一个基于高级仿真构架（HLA）的计算机仿真系统的设计

本文结合雷达电子对抗仿真实例,论述了基于ＨＬＡ的分布交互式多机仿真系统ＹＨ－ＮＩ／ＮＲ的体系结构,运行支持系统,仿真应用对象模,联邦总管和通信网络,及其设计与实现问题。     

基于HLA的仿真程序设计研究及其应用

建模与仿真高层体系结构(HLA) 已成为电气和电子工程师协会( IEEE) 标准,正在成为今后仿真发展的主要方向.但是目前大多数学者只专注于HLA理论研究或者只从联邦内部数据交换的角度来研究基于HLA的仿真程序设计,缺乏直观性和实用性.文中从程序设计的角度、以C 语言实现为例剖析了HLA的编程代理模型和联邦成员代码的三个职责,并且还详细分析了FED文件中定义的对象类和交互类与联邦成员文件结构的对应关系,然后从联邦的执行过程出发给出了基于Windows方式下联邦成员的程序设计框架,最后以一个简单的planetrace联邦的例子来说明了联邦成员仿真程序的实现流程.     

基于HLA的便携防空导弹集成演练系统的研究

为满足便携防空导弹模拟训练器的需求,结合正在研究的课题,设计了模拟训练系统的体系结构,描述了其功能特点.高层体系架构HLA是建模仿真领域的通用技术框架,虚拟现实技术是现代仿真技术的重要发展方向,解决了系统协同训练的问题并使模拟训练器的可视化效果大大提高.在简单介绍HLA/RTI并分析了该训练仿真系统的工作原理之上,提出了便携防空导弹集成演练系统基于HLA的技术解决方案,并初步实现了该训练仿真系统,最后对主要的联邦成员进行了说明并描述了防空训练的整个仿真过程,为相关系统的设计提供了参考.     

基于HLA无源干扰仿真系统的CGF建模的研究

在了解分析高级体系结构HLA的基础上,以无源干扰仿真系统为例,由计算机生成和控制多个CGF仿真实体,并通过对实体的动态建模、智能决策建模,和由RTI控制仿真系统的时空一致性,自主地对仿真环境中的战场态势做出最佳决策,并按智能决策发射干扰弹,组织有效对抗.建模理论和方法的研究在仿真技术领域一直占有主导地位,此无源干扰仿真系统的CGF建模,增加了虚拟战场环境的复杂度和逼真度,对武器研制的可行性分析、测试与评估、参与者的训练等发挥了重要的作用,达到了仿真与建模的高效性.     

云计算联盟体系结构建模研究

云计算联盟的体系结构对云计算联盟的设计、实现和资源管理效率产生重要的影响。由于云计算联盟的构成和运行过程具有典型的复杂系统特性,基于涌现理论和复杂网络理论对云计算联盟的体系结构进行建模,提出了一种基于域和复杂网络理论的云计算联盟体系结构模型,并对该模型中资源的发布和发现机制进行了详细的研究。