理论 theory 理论学习 study of the theory; 理论联系实际 integration of theory with practice; unite theory with practice; 理论脱离实际 theory divorced from practice; discrepancy between theory and practice; 在理论上 in terms of theory; on the theoretical plane; theortically; 理论队伍 theoretical contingent; 理论概括 theoretical generalization; framework; 理论根源 theoretical source; 理论工作 theoretical work; 理论公式 theoretical formula; 理论化 theorization; 理论基础 rationale; 理论家 theoretician; 理论价格 theoretical price; 理论科学学 theoretical science of science; 理论框架 theoretical frame; 理论轮廓 theoretical profile; 理论骗子 theoretical swindler; 理论水平 theoretical level; 理论思维 theoretical thinking; 理论素养 theoretical attainment
Turbo code is regarded as the milestone in channel encoding theory history for its performance closing to shannon limit , which makes us covert to decrease the numbers of light weight code ( error coefficient ) from increasing the minimum hanming weigh . the research and analysis are concentrated on the following : 1 Turbo码具有近shannon限的性能,它的出现被看作是信道编码理论发展史上的一个里程碑,它使人们设计信道编码的方法从增加码的最小汉明距离转向了减少低重量码字的个数(错误系数) 。
It is considered as the most exciting and potentially important development in coding theory in recent years . its invention has changed the conventional design principles of the coding scheme from the attempt to increase the minimum hamming distance of the code to the goal of reducing the number of code words with low hamming weights Turbo码具有近shannon限的性能,它的出现被看作是信道编码理论发展史上的一个里程碑,它使人们设计信道编码的方法从增加码的最小汉明距离转向了减少低重量码字的个数(错误系数) 。
Based on the fact that various forms of bill of material ( bom ) are widely used to solve the existing problems in manufacturing process in the erp system , it is proposed that it is necessary to introduce qbom into erp . the framework of qbom and the principle of quality failure code is discussed . a model of qbom and a quality failure code of the key component of product in the qis model is then designed 从目前erp系统使用的物料清单bom的多种形式解决企业制造中的实际问题出发,提出在erp系统的qis中引入质量物料清单( qbom )的思想,研究了qbom的结构和qbom中关键件的质量故障编码理论与方法,并对qbom进行详细的设计。
Higher mathematics , visual basic programming design , fundamentals of law , linear algebra , fundamentals of , computer application , physical education , computer networks and communication , c + + with object - oriented , programming , data structures , philosophy and political theory , programming in c language , operating systems , software test technology , relations on business , digital logic circuit , international software development , social analysis and government policy , introduction to java visual foxpro database systems and program design , e - business , introduction to programming with an application framework , software engineering , introduction to web page design and programming 高等数学、大学计算机应用基础、程序设计教程软件工程、用户界面设计、电子商务、软件工程、数据库应用与程序设计、线性代数、编码理论基础、信息管理基础、软件成本估算、质量管理、计算机软件技术基础、实用软件体系基础、大型软件体系结构、软件测试技术、客户关系管理、电子商务、国际化软件开发、现代项目管理、计算机网络与通信。
It reframes the traceback problem as a polynomial reconstruction problem , and uses techniques from algebraic coding theory to provide robust methods of transmission and restriction . the scheme is a new solution to the traceback problem during a dos attack ; the honeypot for ddos , which is a tool of traceback , lures the attacker to believe that he successfully compromised a slave for his needs , convincingly simulating the architecture of a potential ddos attack ; the source - based approach to ddos defense , which is a useful adjunt to traceback systems , deploys a ddos defense system at source - end networks . attacks are detected by monitoring two - way traffic flows , and the attacks originating from source networks are stopped by rate - limiting ; the routing mechanism based on pushback treats ddos attacks as a congestion - control problem 最后,就有关ddos攻击反向追踪问题,从四个方面对其解决方案进行了研究:在分析比较几种反向追踪算法的基础上,着重研究了代数方法编码反向追踪信息的方案,该方案把追踪重构问题当作多项式重构问题,使用代数编码理论技术提供鲁棒的传送和重构方法,是dos攻击过程中的反向追踪问题的一种新的解决方法; ddos陷阱作为反向追踪的工具,引诱攻击者相信自己成功与所需的傀儡主机通话,令人信服地模拟出潜在ddos攻击体系结构;基于源的ddos防御方法作为反向追踪有用的补充,将防御系统部署在源网络,通过监控双向流量检测攻击和限制速率终止来自源的攻击;基于向后倒推的防御ddos的路由机制把ddos攻击看作拥塞控制问题,添加功能到每个路由器来检测并优先丢弃可能属于攻击的包,通过向后倒推上级路由器也得到通知而把这样的包丢弃。
After summarize the basic theory on image code compress , we firstly introduce the vector quantization theory , and we also propose a lbg improved algorithm based on simulated annealing with experimentation to verify the performance . secondly , we introduce the wavelet transform theory and the ezw algorithm used in the area of image compression . based on the former two theories , we propose a wavelet transform cross - band vector quantization based on human vision , and we verify the correction with experimentation 在概述了图像压缩编码理论的基础上,首先介绍矢量量化压缩编码理论,提出了一种基于模拟退火的lbg改进算法,并通过实验验证了改进算法的性能;接着介绍小波变换及其应用于图像压缩编码的相关理论,重点介绍了基于小波变换的嵌入零树编码( ezw : embeddedzerotreeswavelet )算法;在矢量量化和小波变换的结合方面,提出了一种基于视觉特性的小波变换跨带矢量量化压缩编码方案,并通过实验验证了算法的性能;最后,在并行性探讨方面,设计了一种基于数据分割的二维dct图像压缩编码算法,并在pvm实验环境下验证了算法的性能。
We firstly summarize the basic theory on image code , introduce some familiar compression techniques and some international compression standards on image and video frequency ; and then , we introduce the basic theory on wavelet transform code and the jpeg2000 standard and its pivotal technique ; at last , we mainly study the embedded zerotrees wavelet ( ezw ) code , we propose a compression technique based on modification of original ezw coding , the main objective of this improved algorithm is to enhance compression ratio of an image with minimal loss during reconstruction , and we verify the improved algorithm ' s performance by doing experiments 首先概述图像编码理论的基本原理和方法,介绍了一些常见的压缩方法和一些涉及图像、视频的国际压缩标准;接着介绍了小波变换及其应用于图像压缩编码的相关理论,在此基础上介绍了jpeg2000标准及其关键技术;最后重点研究了基于小波变换的嵌入零树编码( ezw : embeddedzerotreeswavelet )算法,并在此基础上提出了一种改进算法,改进算法目的是以较小的图像重建质量损失来获得压缩率的提高,并进行了实验验证,验证了该改进算法的合理性和有效性。
On the base of researching the theory of the scheme and analyzing the signal feature , it is obtained that the existence manners and character of distance information in the differential frequency signal . at the same time , a new conclusion is gained that the technology of frequency agility can decrease the constant error of system . it is also to say that frequency agility and frequency modulation fixed - distance fuze has the similar feature to random period frequency modulation fixed - distance fuze . according to the theory of address coding in the hopping - frequency communication , the paper presents the principle of selecting the frequency agility sequence which fit to the radio fuze and constructs the frequency agility sequence family based on the rs codes 在深入研究方案原理和分析信号特征的基础上,获得了该体制引信差频信号中,距离信息的存在形式和特点,得出了频率捷变技术的引入降低了系统定距固定误差这一新的结论,即频率捷变调频定距引信在定距性能上具有类似随机周期调频定距的特征。本文引入跳频通信地址编码理论,结合无线电引信的具体特征,提出了适用于无线电引信的频率捷变序列的选择原则,并构造了基于rs码的宽间隔频率捷变序列族。
According to the project of adaptive multi - rate speech coding ( amr ) being put forward by the third generation group of the mobile communication , this paper takes the principle of the speech arithmetic as the base , studies the technologies including the source controlled rate , voice activity detector , comfort noise and the error concealment unit in amr , discusses its the characteristic of adaptation and analyses its performances particularly . amr c codes are researched carefully through the modules being divided into and debugged under the tms320c54x provided by the ti corporation , and optimized in selecting the method of c code embedded assembler codes and simplified in the search codebook combining with the theory of speech coding , which are based on the realization about theory and practice of the optimization of amr speech coding 从自适应多码率语音编码算法的c代码出发,对它进行模块划分后作了系统分析,将其在vc下调试通过,进一步在ti公司提供的tms320c54x环境中进行调试,结合语音编码理论,对算法进行优化,采用了在c代码中嵌入汇编和简化自适应码本和固定码本搜索的方法,部分地提高了c代码效率,为实现自适应多码率语音编码的优化奠定了理论和实践基础。