共查询到20条相似文献，搜索用时 203 毫秒
1.
Collaborative Filtering (CF) technique has proved to be one of the most successful techniques in recommendation systems in recent years. However, traditional centralized CF system has suffered from its limited scalability as calculation complexity increases rapidly both in time and space when the record in the user database increases. Peer-to-peer (P2P) network has attracted much attention because of its advantage of scalability as an alternative architecture for CF systems. In this paper, authors propose a decentralized CF algorithm, called PipeCF, based on distributed hash table (DHT) method which is the most popular P2P routing algorithm because of its efficiency, scalability, and robustness. Authors also propose two novel approaches: significance refinement (SR) and unanimous amplification (UA), to improve the scalability and prediction accuracy of DHT-based CF algorithm. The experimental data show that our DHT-based CF system has better prediction accuracy, efficiency and scalability than traditiona 相似文献
2.
INTRODUCTION Research interest in immune system has in-creased over the past few years, and because of its special information processing capabilities, it has been applied to solve many problems (de Castro and Von Zuben, 1999; Hunt and Cooke, 1996). Among these research areas, network security is one of the hot spots and has been considered as analogous to im-munity in natural systems. Researchers at the Uni-versity of New Mexico did a lot of research in this area (Forrest et al., 199… 相似文献
3.
4.
耿让 《中学英语之友(高一版)》2007,(2)
Do you like Beijing Opera? Beijing Opera-Peking Opera has existed for over 200 years. It is widely regarded as the highest expression of the Chinese culture. It is known as one of the three main theatrical systems in the world. Artistically, Beijing Opera is perhaps the most refined form of opera in the world. It has deeply influenced the hearts of the Chinese people. Although it is called Beijing Opera, its origins are not in Beijing but in the Chinese provinces of Anhui and Hubei. Beijing Opera got its two main melodies, Xi_Pi and Er_Huang, from Anhui and Hubei operas. It then absorbed music and arias from other operas and musical arts in China. 相似文献
5.
The old man loves the sea, ac-cepting(接受)its hardship and cruelties(残酷)as one might accept the fickle-ness(感情上的变化无常)of a womanhe loved. By the time dawn,he has alreadybaited several lines with sardines(沙丁 相似文献
6.
孟书苹 《重庆大学学报(英文版)》2005,4(2):84-89
1 Introduction 1 With the development of the application of wavelet transform (WT), the speed of wavelet transform as a hot issue has been put forward. Fast algorithms of wavelet transform have been studied by many scholars. The Mallat pyramid algorithm put forward by Mallat, as the earliest one in this category, greatly reduces the arithmetic complexity of WT, and plays an important role in the theoretical research of the theory of wavelets. Since its coming into being, various fast algori… 相似文献
7.
"All the articles in black are ridiculous,while in fact,they are full of sorrowful tears.Everyone views the author as a fool,while no one could find his woe."(Cao Xueqin,1994:1) That is written in the beginning of "A Dream of Red Mansions".As is known to us,this work has rooted its popularity in the hearts of world readers.however,once upon time,few people noticed its influence on another book,which is the masterpiece of LinYutang(a famous Chinese writer who creates his works mostly in English)--"Moment in Peking".Nowadays,"Moment in Peking" was becoming more and more conspicuous;because of its considerably connection with "A Dream of Red Mansions".It is an English novel written by LinYutang between the year 1938 and 1939 when he resided in Paris,and was regarded by the"Times" as the most classic work,which might become "the one reflecting the reality of the society at that time in China".Along with people’s focus on "A Dream of Red Mansions",its place has been promoted,too.This paper aims at analyzing the similarities and differences between these two famous works. 相似文献
8.
With the development of economic globalization,legal English has been developing very fast as one kind of ESP.Compared with general English,legal English is a special language style,which is characterized by stability,oddities and exactness.The language used in legal document belongs to a special kind of legal English,and has its own language characters like other social dialects.The paper analyses the features of the language of legal document from lexical and syntactic level. 相似文献
9.
LIULi-fang 《邯郸职业技术学院学报》2004,17(3):26-27
This essay through discussing the development of sonnet focus on the delight and pleasure of poetry. In great poetry the form is a living organism which grows from the civilization surrounding the poet as well as from his individual talent, and poetry puts more emphasis on the musical properties of language. So a study of poetic form and rhythms is significant. Sonnet is one of the most ubiquitous of Enghsh fixed forms, although it is not the native form of English poetry. Sonnet has a neat form and a rigid rhyme scheme which undergoes changes in its development. 相似文献
10.
With the development of the cross-cultural communication,more and more people have recognized the interaction between language and culture.Each culture has its own characteristic and is different from one another.Because of cultural differences,difficulties often arise in communication between different people.In China,English is taught as a foreign language.Both teachers and students should be aware of the differences between eastern and western culture in their teaching and study. 相似文献
11.
黄力 《柳州职业技术学院学报》2007,7(2):107-111
移动IP技术的出现使移动用户在Internet的海洋里自由翱翔。为了安全起见,企业和家庭网络都采用防火墙安全策略。在没有取得授权的情况下,移动用户无法访问企业或家庭的网络,一定程度限制了移动用户对网络资源的获取。本文提出一套基于外部代理的移动IP安全穿越防火墙的解决方案,方案设置一个移动节点,该节点可以从外部代理中获得一个授权地址,通过该地址实现与其家乡代理和通信对端的通信,在不修改协议和网络实体的情况下,利用IPSec协议实现防火墙的安全穿越和端到端的安全通信。 相似文献
12.
分析了制造网格体系结构,介绍了网格计算常用的认证和授权安全策略.依据其结构特点,利用建立可信任分层代理,实现用户的一次认证,从而构建了一种更安全的认证分层代理模型,进一步确保了系统的安全. 相似文献
13.
14.
田敬军 《唐山师范学院学报》2003,25(2):69-72
安全是移动Agent系统中的最重要、最关键的问题之一，可以分成恶意Agent和恶意主机两方面的问题，前者的解决较为容易，在大部移动Agent系统中都已经实现，通常采用认证、授权和资源分配机制来解决，后者比较困难，目前有组件、复制和投票、自我认证和加密函数等部分解决方案。然而，仅依靠软件手段解决移动Agent的安全问题尤其是恶意主机问题是不够的，最好是采用软件和硬件相结合的解决方案。 相似文献
15.
YANG Rui-jun XIA Qi PAN Qun-hua WANG Wei-nong LI Ming-lu 《浙江大学学报(A卷英文版)》2006,7(4):493-501
INTRODUCTION Mobile ad hoc networks are under active research focused on issues such as routing, security (Venkatra- man and Agrawal, 2003) and data management (Fan and Zhang, 2004). People have proposes many kinds of security mechanisms such as SAR (Yi et al., 2002), SRP (Papadimitratos and Haas, 2002), ARAN (San- zgiri et al., 2002), ARIADNE (Hu et al., 2005) and SEAD (Hu et al., 2002) for networks. The resource consumptions of security mechanisms are always large in mobile … 相似文献
16.
网格计算是一门新兴的技术,它能够为用户和应用提供对资源和大量IT功能的无缝访问.安全问题是网格计算成败的关键.通过分析网格计算的基本特点和安全要求,结合网格安全策略和安全体系模型,给出了该模型的一种实现方法. 相似文献
17.
移动互联时代,大部分第三方即时通信类软件使用者不能完全掌握聊天数据,易造成数据被分析等安全问题。针对企业级即时通信安全问题,提出一套利用云计算特性的即时通信系统。系统采用C/S模式,服务器部署在云端,能够使用户独立部署系统,做到服务器私有,数据信息加密保存,客户端包含移动端和桌面端,数据加密传输。通过常见攻击手段安全分析和系统性能分析,验证了系统安全性与可靠性。该系统已上线使用且运行良好。 相似文献
18.
教学网格门户能有效地改善网络教学环境,提高校园网资源的利用率。一个有效满足最小特权原则的访问控制机制必不可少。坚持最小特权原则,要不断调整用户权限,适应当前情况。为教学网格门户提出一种上下文感知的访问控制机制,建立在网格安全基础设施提供的安全机制上,增强安全性。提供紧凑、准时的权限,使授权用户能依环境访问特定对象。上下文的不断变化引发权限的持续调整,从而减少执行任务期间损害信息完整性的风险。 相似文献
19.
刘畅 《湖北广播电视大学学报》2013,33(2):155-156
近几年,智能手机作为新兴的移动终端呈现了井喷式的发展,伴随着这一趋势,手机信息安全的重要性也与日俱增。如何防范手机病毒,逐渐成为一个重要的问题。首先介绍了手机病毒的特征与常见攻击手段,随后分析了目前两大智能手机系统的安全机制及面临的问题,最后对如何保障手机用户的信息安全提出了建议。 相似文献
20.
随着移动互联网的快速发展,用户已习惯通过移动终端进行移动支付、移动办公、移动娱乐等,但用户在享受其带来便利的同时,也面临着身份仿冒等安全威胁。由于移动终端的特性,以 UKey 为载体的传统数字证书无法在移动终端得到应用。以移动终端数字证书应用为导向,通过对现有移动终端数字证书存储方式的分析,比较现有存储方式的优缺点,提出基于 TEE+SE 的移动终端数字证书方案,解决了现有蓝牙 KEY 携带不便、服务端私钥模式对用户风险较大,以及密钥分割方法与电子签名法兼容性等问题,并指出随着移动终端的发展,移动终端厂商将逐步占据主导地位,基于 TEE+SE 的数字证书解决方案将成为未来移动终端数字证书的发展方向。 相似文献