基于P2P技术的网格资源管理方法

网格计算的关键技术是资源管理,如何有效地对网格资源进行管理调度是一个网格系统是否可用的关键问题。基于网格资源的特点,文本试图在网格环境中引入对等思想,利用P2P技术来有效地管理动态的网格计算资源。     

Hybrid ants-like search algorithms for P2P media streaming distribution in ad hoc networks

Media streaming delivery in wireless ad hoc networks is challenging due to the stringent resource restrictions,po-tential high loss rate and the decentralized architecture. To support long and high-quality streams,one viable approach is that a media stream is partitioned into segments,and then the segments are replicated in a network and served in a peer-to-peer(P2P) fashion. However,the searching strategy for segments is one key problem with the approach. This paper proposes a hybrid ants-like search algorithm(HASA) for P2P media streaming distribution in ad hoc networks. It takes the advantages of random walks and ants-like algorithms for searching in unstructured P2P networks,such as low transmitting latency,less jitter times,and low unnecessary traffic. We quantify the performance of our scheme in terms of response time,jitter times,and network messages for media streaming distribution. Simulation results showed that it can effectively improve the search efficiency for P2P media streaming distribution in ad hoc networks.     

对P2P技术传播涉及相关法律问题的分析

先简要介绍了一种新兴的互联网技术P2P技术的工作原理和应用,以及其带来的主要法律问题,然后结合全球首宗因P2P应用软件——BT下载侵权行为被法院裁定罪名成立的案例,分析其对现行版权制度的冲击和影响,提出保障其健康发展的法律建议。     

XML在Web中的应用研究

XML(可扩展标记语言)作为W eb标准技术支持的一种具有风险描述、开放性、信息加密优势.本文从原理上阐述了这三个优势在W eb风险描述、W eb服务、W eb中信息加密上的应用.     

《中国十大旅游名胜》一课的多媒体网络教学

通过一节网络实验课的课例教案，展现了网络教学中教师的主导作用的发挥与学生的自主学习的训练。     

Cookie技术在Web日志挖掘预处理中的应用

W eb日志的数据挖掘,可以发现用户访问页面的行为模式,改进W eb站点的性能和结构,提高查找信息的质量和效率.对W eb日志挖掘预处理的数据清洗、识别用户、识别用户会话和识别片断四个主要阶段所要完成的任务进行分析,论述了现有W eb日志预处理方法中的用户识别技术,提出了一种基于Cook ie技术和扩充日志属性的用户识别方法.     

Should Science be Taught in Early Childhood?

This essay considers the question of why we should teach science to K-2. After initial consideration of two traditional reasons for studying science, six assertions supporting the idea that even small children should be exposed to science are given. These are, in order: (1) Children naturally enjoy observing and thinking about nature. (2) Exposing students to science develops positive attitudes towards science. (3) Early exposure to scientific phenomena leads to better understanding of the scientific concepts studied later in a formal way. (4) The use of scientifically informed language at an early age influences the eventual development of scientific concepts. (5) Children can understand scientific concepts and reason scientifically. (6) Science is an efficient means for developing scientific thinking. Concrete illustrations of some of the ideas discussed in this essay, particularly, how language and prior knowledge may influence the development of scientific concepts, are then provided. The essay concludes by emphasizing that there is a window of opportunity that educators should exploit by presenting science as part of the curriculum in both kindergarten and the first years of primary school.     

虫媒登革病毒的研究——Ⅱ.登革病毒非结构蛋白NS1的纯化、鉴定及其在临床检测应用

本文从纯化Den2 NS1,Mab入手,自制了Mab亲和层析系统,从感染Den2的细胞膜中,分离提取了天然的Den 2 NS1双体,比较其NGC株与我国地方株(H-87)NS1的理化性质及组成,并对某些重要的生物学性质进行了综合性研究。同时,利用上述研究结果建立了检测DF病人血清特异NS1抗体的新方法,探索其协助临床诊断及研究的可能性。     

J2EE平台在行政审批服务系统中的应用

本文分析了电子政务对国民经济所起的重大作用,简要介绍了当前流行的J2EE架构的分布式对象结构特点。设计了一个J2EE架构下的行政审批服务系统,它由客户层、中间层和企业信息系统层等三个层次组成。同时,对系统的设计方法、软件结构及实现技术进行了探讨。     

Thermodynamic Analysis and Comparison on Low Temperature CO_2-NH_3 Cascade Refrigeration Cycle

Intheapplicationsofindustrialandcommercialrefrig erationsystem ,iftherequiredrefrigerationtemperatureisverylow ,theconventionalvaporcompressionsystemisdiffi culttomeettherequirementbecausewhenthedifferencebe tweentheevaporatingtemperatureandthecondensingtemper atureissohighthatitishardtofindarefrigeranttomeettheneedsasthecondensingpressureisnottoohighandtheevap oratingpressureisnottoolow .Whentherefrigeratingtemper atureisverylow ,thecascaderefrigerationcycleissuitabletobeused .Itcannotonlysat…