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201.
基于VRML场景的网上虚拟配画环境设计   总被引:1,自引:0,他引:1  
介绍了在一个电子商务网站中,如何运用asp(服务器端的脚本语言)、JavaScript(脚本编程语言)和VRML(虚拟现实建模语言)与数据库互联,实现装饰画的网上自主配画和订购。特别是用户可以上传自己家的照片,在网上可以预览装饰画放在自己家中的效果。该文提出了采用分层图像和透明处理的方法解决了遮挡问题,采用ASP与VRML结合的方法解决了虚拟场景与数据库的连接。  相似文献   
202.
0 IntroductionThe security of most commonly used cryptographicschemesis essentially based onthree families of compu-tational problems :the integer factoring problem(RSAprob-lem) ,the Diffie-Hell man problemand the discrete logarithmproblem,andthe elliptic curve variants thereof .Inthe middleof 1990s , Shor[1], Bonehet al[2]presented some remarkablequantumalgorithms which can solveinteger factoring problemand discrete logarithmproblemover any group including Ga-lois fields and elliptic curve…  相似文献   
203.
0 IntroductionDigital signatureis a key technique to provide datainteg-rity andsource authenticationcapabilities to enhance da-ta trustworthiness in trusted computing platform. Most cur-rent digital signature schemes are based on complex mathe-matical problems , such as integer factoring, discrete log-arithm,and discrete logarithm on elliptic curves . The hard-ness of these underlying mathematical problems is really un-certain at present . Merkle treeis a method used for authenti-cation and di…  相似文献   
204.
The subliminal channel is used to send a secret message to an authorized receiver; the message cannot he discovered by any unauthorized receivers. Designated verifier signature (DVS) provide authentication of a message, we design a DVS scheme with message recovery mechanism and use it as a subliminal channel. In order to share a message among n users securely and allows t or more users can reconstruct the secret in dynamic groups, we combine both subliminal channel and (t, n) threshold cryptography. Then we proposed a threshold subliminal channel which can convey a subliminal message to a group of users based on message-recovery designated verifier signatures. Reconstructing the subliminal message relies on the cooperation of t or more users in the group and they can verify the validity of the subliminal message. Security and performance analysis show that the proposed scheme is secure and efficient.  相似文献   
205.
Reconfigurable computing has grown to become an important and large field of research, it offers advantages over traditional hardware and software implementations of computational algorithms. The Advanced Encryption Standard (AES) algorithm is widely applied in government department and commerce. This paper analyzed the AES algorithms with different cipher keys, adopted a novel key scheduler that generated the round key real-time, proposed a dynamically reconfigurable encryption system which supported the AES algorithm with different cipher keys, and designed the architecture of the reconfigurable system. The dynamically reconfigurable AES system had been realized on FPGA. The result proves that the reconfigurable AES system is flexible, lower cost and high security level.  相似文献   
206.
安东  Li  Weiguang  Cui  Fuyi  Wang  Rui 《高技术通讯(英文版)》2006,12(1):91-96
The object of this paper is to evaluate the removal of disinfection by-products formation potential by artificially intensified biological activated carbon(BAC) process which is developed on the basis of traditional ozone granular activated carbon (GAC). The results show that 23.1% of trihalomethane formation potential (THMFP) and 68% of haloacetic acid formation potential (HAAFP) can be removed by BAC, respectively. Under the same conditions, the removal rates of the same substances were 12.2% and 13-25% respectively only by GAC process. Compared with GAC, the high removal rates of the two formed potential substances were due to the increasing of bioactivity of the media and the synergistic capabilities of biological degradation cooperating with activated carbon adsorption of organic compounds. BAC process has some advantages such as long backwashing cycle time, low backwashing intensity and prolonged activated carbon lifetime, etc.  相似文献   
207.
In this paper, we propose a partially non-cryptographic security routing protocol (PNCSR) that protects both routing and data forwarding operations through the same reactive approach. PNCSR only apply public-key cryptographic system in managing token, but it doesn't utilize any cryptographic primitives on the routing messages. In PNCSR, each node is fair. Local neighboring nodes collaboratively monitor each other and sustain each other. It also uses a novel credit strategy which additively increases the token lifetime each time a node renews its token. We also analyze the storage, computation, and communication overhead of PNCSR, and provide a simple yet meaningful overhead comparison. Finally, the simulation results show the effectiveness of PNCSR in various situations.  相似文献   
208.
0 Introduction Watermarking relational database become a hotspot in recent years, it aims to protect copyrights by intro- ducing small errors into the original content without af- fecting the usability for intended purpose. Although some pioneer efforts h…  相似文献   
209.
服务质量管理模式的研究   总被引:10,自引:0,他引:10  
阐述了服务质量的含义,然后构造出一个以顾客为中心的服务质量管理模式。它包括一个服务三角形,由服务战略,服务系统、服务人员三个因素构成,这三个因素都面向顾客这个中心,彼此又相互关联。  相似文献   
210.
审计日志的关联规则挖掘   总被引:2,自引:0,他引:2  
研究了在入侵检测系统中利用数据挖掘技术从审计日志中挖掘关联规则的方法,针对现有关联规则算法应用于入侵检测系统引起的问题,提出了利用本质属性限制无趣规则的产生、利用行向量的位运算提高Apriori算法时间性能的一种高效改进算法。该算法不需生成候选频繁集和剪枝操作,避免了因无趣规则引起的大量运算。因而能提高入侵检测系统的效率。  相似文献   
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