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.     

灵智的竞争才是美丽的生命——试论石涛的"一画"论

石涛的画论思想实是中国绘画美学的一总结形态,但其在总结的基础上鲜明地提出了绘画乃是出自于“心”的创造,是艺术家主体精神无限拓展的产物,因为只有灵智的竞争才是美丽的生命。     

一个K-均值文档聚类的改进算法

k均值算法是一个常用的局部搜索算法，它的主要缺陷是容易陷入局部极小，并且该局部极小解与全局最优解往往有很大的偏差。本文提出一个基于K-均值的迭代局部搜索文档聚类算法。该算法以k均值算法所得到的解作为初始解，从该初始解开始作局部搜索。在搜索过程中接受部分劣解。当解无法改进时，算法对所得到的局部极小解做适当强度的扰动后进行下一次的迭代，以跳出局部极小，从而拓展了搜索的范围。实验结果表明该算法对文档数据集聚类的正确性迭99％以上。     

基于B/S模式的海量数据报表的实现

本文基于海量数据和网络打印速度之间的矛盾问题,通过几种报表实施方案的对比,提出了利用操纵Excel引擎方式解决网络打印海量数据报表问题的方法。以某煤矿企业考勤综合管理系统的考勤报表为应用背景,研究了基于B/S模式的海量数据报表的实现过程,讨论了客户端与服务器端的设置方式。应用证明该方法切实可行,可以有效地解决网络打印海量数据报表效率低的问题。     

搜索引擎Google的检索功能及PageRank技术分析

本文介绍了搜索引擎Google的特点和检索功能，并重点介绍了其PageRank专利技术的概念及计算方法。     

自动分类在搜索引擎性能优化中的应用

本文论述了自动分类在搜索引擎中的作用,介绍了网页自动分类实现的方法,分析了网络自动分类系统的实例,最后展望了自动分类在搜索引擎中的应用前景.     

Analyzing imbalance among homogeneous index servers in a web search system

The performance of parallel query processing in a cluster of index servers is crucial for modern web search systems. In such a scenario, the response time basically depends on the execution time of the slowest server to generate a partial ranked answer. Previous approaches investigate performance issues in this context using simulation, analytical modeling, experimentation, or a combination of them. Nevertheless, these approaches simply assume balanced execution times among homogeneous servers (by uniformly distributing the document collection among them, for instance)—a scenario that we did not observe in our experimentation. On the contrary, we found that even with a balanced distribution of the document collection among index servers, correlations between the frequency of a term in the query log and the size of its corresponding inverted list lead to imbalances in query execution times at these same servers, because these correlations affect disk caching behavior. Further, the relative sizes of the main memory at each server (with regard to disk space usage) and the number of servers participating in the parallel query processing also affect imbalance of local query execution times. These are relevant findings that have not been reported before and that, we understand, are of interest to the research community.     

知识网络结构、跨界搜索对组织突破性创新的影响:美国人工智能技术领域专利的分析

知识要素之间耦合形成的知识网络结构和跨界搜索是突破性创新形成的前端因素,知识网络结构特征和跨界搜索程度的不同,对突破性创新影响也不同。研究者利用美国人工智能技术领域的专利数据,构建了243家组织的知识网络,并考察了知识网络中心势、结构洞以及跨界搜索对相关组织的影响。研究表明,知识网络中心势、结构洞与组织突破性创新绩效呈正相关的关系;知识网络中心势、结构洞与跨界搜索呈正相关的关系。同时研究也验证了跨界搜索会正向影响突破性创新,并呈现部分中介效应。     

网络信息分类组织研究的重点、热点及其他

概括了6年来网络分类信息组织研究的重点、热点、特点及问题.     

搜索引擎优化策略研究

搜索引擎是互联网上应用最为广泛的工具,是用户寻找网上信息和资源的主要途径。搜索引擎营销已经成为网络营销最重要的组成部分。如何使自己的网站被主要的搜索引擎收录,并且得到较好的排名,成为网站建设者们不得不考虑的问题。文章首先阐述了搜索引擎的基本含义,然后介绍了搜索引擎优化的重要意义,最后提出了搜索引擎优化的策略。