查询词典 digital

along with the development of digital technology,digital filters are widely used in many fields,this paper introduces how to design a iir digital notch filters in matlab environment.the design of digital notch filters can be achieved through three steps:firstly,the design of analog lowpass filter; secondly,it is analog lowpass to analog band stop filter conversion;at last,using the bilinear transformation make the analog notch filters change into digital notch filters.the paper also introduces how to design the transfer function of the digital notch filters using all the zeros and farthest points at the same time,it also introduces the program of the digital notch filters under butterworth analog lowpass prototype.

摘 要：随着数字技术的发展，数字滤波器在许多领域得到广泛的应用。研究一种在matlab语言环境下设计iir数字陷波滤波器的方法，在数字陷波滤波器设计过程中，先进行模拟低通滤波器的设计，然后进行模拟低通/模拟带阻滤波器转换，最后采用双线性变化法将模拟陷波滤波器转化成数字陷波滤波器。提出一种用所有零点和极点来表达数字陷波器传递函数的方法，同时给出以巴特沃斯模拟低通为原型设计数字陷波滤波器的程序。关键词：无限冲激响应；巴特沃斯滤波器；数字陷波滤波器；matlab；双线性变换

The main content of this thesis includes six parts. First of all, it is a comprehensive systematic introduction about RSA algorithm including the present application situation and principle of RSA algorithm----producing big prime numbers and secret keys, the encryption arithmetic for information and the decryption for secret information, which establish the theory foundation for achieving concrete; secondly, it introduces some basic conception of RSA digital signature and theory of digital signature realizing process; thirdly, it introduces the basic principle of MD5 algorithm; fourthly, it states design and realization of RSA digital signature in detail. The main modules includes producing RSA secret keys, implementation of RSA encryption algorithm and decryption algorithm, producing message digest and realizing digital signature and verification by RSA; the fifth, it carries on testing entirely, analyzing and improving for this system;The sixth, it analyses the security of RSA digital signature and points out the development direction of RSA digital signature.

本文主要研究的内容包括：第一，对RSA算法进行了全面系统的介绍，包括RSA算法的应用现状和原理—大素数的产生、密钥对的产生、对明文的加密运算和密文的解密运算，为具体实现打下了理论基础；第二，介绍了RSA数字签名的一些基本概念和数字签名的理论实现过程；第三，对MD5算法基本原理的介绍；第四，详述了RSA数字签名的设计与实现，主要实现的模块包括RSA密钥的产生，RSA加密算法和解密算法的实现，消息摘要MD的生成以及利用RSA算法实现数字签名和签名的验证；第五，对该系统进行了整体的测试和分析改进；第六，分析了RSA数字签名的安全性，指出了RSA数字签名的发展方向。

In this paper, the concept of network security and security structures of OSI and Internet is introduced, and various threats confronting the computer network are also discussed. Several kinds of network information security technologies, including firewall technology, virtual private network, intrusion detection system, data encryption technology, identity authentication and security protocol etc. are also examined. The security of internal network is the biggest problem in the construction of each network. The solution to this problem lies in setting up a firewall. The theory of a firewall and the approach to its actualization is studied. Intrusion detection system, an important part of the computer network security system, has gained extensive attention. IDS monitors the computer and network traffic for intrusion and suspicious activities. It not only detects the intrusion from the extranet hacker, but also the intranet users. The emergence of virtual private network paves the way for realizing secure connection of LAN quickly and at a relatively low cost. The concept, function, key techniques, including the tunnel technology, and the ways to realize VPN are expounded in this paper. Also introduced is the data encrypt network technology, which is called the soul of computer network security, such as digital digest, digital signature, digital certificate, digital encrypt arithmetic and so on. At the same time, the principle and the process of implementing network security by digital certificate and digital signature, the basic principle and characters of security protocols, and finally, three of the security protocols, concerning the security problems in network, IPsec, SLL and SET are analyzed in detail Computer network system should be a system of dynamic defence, both dynamic and static, passive as well as active, and even offensive, combined with management and technology.

本文系统地介绍了网络安全的概念、OSI及Internet的安全体系结构，并讨论了计算机网络面临的各种安全威胁；内部网络的安全问题是每个建网单位面临的最大问题，可以认为防火墙技术是解决网络安全的一个主要手段，本文研究了防火墙的原理及其实现手段；作为一种主动的防御措施，入侵检测系统作为网络系统安全的重要组成部分，得到了广泛的重视，TDS对计算机和网络资源上的恶意使用行为进行识别和响应，不仅检测来自外部的入侵行为，也监督内部用户的未授权活动；虚拟专用网技术的出现，为实现网络间的连接提供了快速安全但又相对便宜的手段，本文较深入的探讨了实现VPN的隧道技术，并对VPN的概念、功能、实现途径、基本构成、关键技术及发展前景等问题进行了全面论述；数据加密技术是网络安全核心技术之一，本文从数据加密算法、数字摘要、数字签名及数字证书等几方面简要介绍了数据加密技术，并分析用数字证书和数字签名实现网络安全的原理和过程；对安全协议的基本原理、主要特点进行了较为深入的研究，并就网络的安全性问题剖析了三种安全协议：IPsec协议、SLL协议和SET协议。

In this dissertation, digital lock-in detection techniques under integer period sampling and non-integer period sampling are separately investigated (1) Under integer period sampling, digital signal sequence is acquired through sampling the measured signal, but digital reference sequence is acquired through mathematical operation, then digital lock-in detection can be realized by calculating crosscorrelation function of digital signal sequence and digital reference sequence Harmonic measure is also analyzed, and a method of measuring harmonic of a periodic signal under aliasing is put forward.

本文对使用采样ADC把模拟信号转换为数字信号并通过计算数字信号的相关函数来实现锁定检测的技术进行了研究，在此基础上设计了一个多功能的数字LIA并在一些科学实验中进行了应用。本文对整周期采样和非整周期采样时的数字锁定检测技术分别进行了研究。(1)在整周期采样时，对被测信号进行采样得到信号序列，而参考序列由数学运算得到，通过计算信号序列和参考序列的互相关函数就可实现锁定检测。

Conference Topics:Digital methods,systems and equipment for image capture;Color Science and Technology for digital imaging system;Digital imaging processing and manipulation;Novel Imaging and related functional materials;UV curing materials and technologies; Digital image rendering and display technologies; Evaluation methods and instrumentation for digital imaging and related performances; Digital media and image performance; Digital output and hardcopy technologies; Digital photofinishing and systems;Digital and on-demand printing/publishing technology and Systems.

会议内容：数字影像的捕获方法、系统与设备；数字影像系统的色彩科学与技术；数字影像处理；新型影像材料和相关功能材料；紫外光固化涂料和固化技术；数字影像渲染和显示技术；数字影像和相关性能的评价方法和设备；数字影像和动画；数字媒体和影像性能；数字输出和硬拷贝技术；数字冲洗胶片和系统；数字印刷与按需印刷技术和系统等。

Firstly this paper dissertates the significance, principle, workflow and characteristics of remote digital proof. Moreover, it puts forward the color management scheme of remote digital proof. And then, through experiments, it describes the process of native digital proof, including setting up ICC Profile which reflects printing characteristics, basic linearization and digital proofer's linearization, setting up ICC Profile which reflects characteristics of digital proofer's paper and ink, and so on. On the basis of that, the process of remote digital proof is set up and realized, including setting up original proof and remote proof. Besides, the chromatism and resolvent is analysised. The color consistency between the two digital proofers is realized. Finally, by setting up RSA digital signature of remote digital proof, the security of network transmission and validity of digital signature is assured.

本论文首先阐述了远程数码打样的意义、原理、组成及特点，并提出了远程数码打样的色彩管理解决方案；然后，通过实验说明了本地数码打样的输出过程，包括创建反映印刷工艺特性ICC Profile、数码打样机基本线性化及数码打样机线性化、创建反映数码打样机纸张、墨水特性的ICC Profile等等；在实现本地数码打样输出的基础上，基于Best Remoteproof建立和实现了远程数码打样，包括创建本地校样和远端校样；并且分析了色差数据以及解决方法，实现了两台远程数码打样机之间的色彩一致性；最后，通过建立远程数码打样的RSA数字签名方案，保证了网络传输数据的安全性以及数字签名的有效性。

The method comprises the steps of: constructing a testing system which inputs digital codes and outputs simulated values of the analog-digital converter; obtaining a comparison table which is output through inputting responded simulated values of different digital codes from 0 to 2N-1 of the analog-digital converter; calculating to obtain an integration non-linear error comparison table corresponding to different digital code input of the analog-digital converter; compensating integration non-linear errors of the analog-digital converter through a hardware compensating method of adding a subtracter; and obtaining accurate analog-digital converter output.

搭建数模转换器的数字码输入-模拟值输出的测试系统；获得数模转换器从0到2 N -1的不同数字码输入响应的模拟值输出的对照表；计算得到数模转换器相应于不同数字码输入的积分非线性误差的对照表；通过加入减法器的硬件补偿方法，补偿数模转换器的积分非线性误差，获得准确的数模转换器输出。

Inputs and Outputs Front Panel: Phones: Standard headphone output jack (gold-plated) Video 4: Gold-plated stereo RCA jacks, gold-plated RCA composite video jack and S-video jack Digital Optical 3 Input: Standard Toslink digital input with a plastic protective plug Digital Coax 3 Input: Standard gold-plated coaxial digital jack Back Panel: AM Loop Antenna Input: Two thumb screw connections FM 75-ohm Antenna input: Threaded "F" type connector Tape Input/Output: Stereo RCA jacks Video 3 Input: Stereo RCA jacks, RCA composite video jack and S-video jack Video 2 Input/Output: Stereo RCA jacks, RCA composite video jacks and S-video jacks Video 1 Input/Output: Stereo RCA jacks, RCA composite video jacks and S-video jacks DVD Input: Stereo RCA jacks, RCA composite video jack, and S-video jack CD Input: Stereo RCA jacks Monitor Output: RCA composite video jack and S-video jack Subwoofer Preamp Output: 1 RCA jack Digital Optical 1 Input: Standard Toslink digital input with a plastic protective plug Digital Optical 2 Input: Standard Toslink digital input with a plastic protective plug Digital Coax 1 Input: Standard coaxial digital jack Digital Coax 2 Input: Standard coaxial digital jack Digital Optical Output: Standard Toslink digital output with a plastic protective plug Digital Coax Output: Standard coaxial digital jack Remote Control In/Out Jacks: One mini-jack input and one mini-jack output Speaker Outputs: Binding post outputs for front left, front right, surround left, surround right, and center speakers (posts are not 5-way binding posts, because each post has a plastic collar that prevents used with spade lugs and the posts are too far apart to use dual banana plugs) AC Outlets: One unswitched AC outlet and one switched AC outlet

投入和产出接待小组：电话：标准耳机输出插孔视频4 ：镀金立体声RCA插孔，镀金的RCA复合视频插孔和S - Video插孔数字光学3输入：标准Toslink数字输入与一个塑料保护插头数字同轴3输入：标准镀金同轴数字接口背板：上午环形天线输入：两个拇指螺丝连接调频75欧姆天线输入：线程的& F &型连接器，磁带输入/输出：立体声RCA插孔视频3输入：立体声RCA插孔，插孔的RCA复合视频和S - Video插孔视频2输入/输出：立体声RCA插孔，莲花复合视频插孔和S - Video插孔视频1输入/输出：立体声RCA插孔，插孔的RCA复合视频和S端子接口的DVD输入：立体声RCA插孔，插孔的RCA复合视频和S -视频CD输入端插孔：立体声RCA插孔监视器输出：复合视频的RCA插孔和S - Video插孔低音前置输出： 1的RCA插孔数字光1输入：标准Toslink数字输入与一个塑料保护插头数字光2输入：标准Toslink数字输入与一个塑料保护插头数字同轴输入1 ：标准同轴数字接口数字同轴2输入：同轴数字接口标准数字光输出：标准Toslink数字输出塑料防护插件数字同轴输出：标准同轴数字接口远程控制在/输出插孔：一个迷你插孔输入和1个小型插孔输出扬声器输出：结合后产出的左前方，右前方，左环绕，右环绕和中心发言（职位不是5个具有约束力的方式，因为每个职位有一个塑料环，可以防止使用铁锹派和职位过于遥远使用双香蕉插头）交流插座：一个unswitched AC插座和一个开关AC电源插座

The invention discloses a digital good transaction system and the method. It mainly carries on coding process to at least one digital good in a content downloading center into a coded digital good, and the coded digital good will be transmitted to at least one content downloading station with real memory transmission path, when the consumer selects a digital good, the user can uses a content downloading card into a content downloading station, uses a reality transmission path to store the digital good to be purchased, and uses a network transmission wire to connect the content downloading center, the center incriminates the card number in order to generate a card number decoding data, and download the decoding data into a content downloading card, when the consumer want toe buy a digital good, the content can be downloaded into a content card reader, and the reader incriminate the card number to reduces the decoded data and the digital good, in order to generate the digital good which can be read and used.

本发明公开了一种数字商品交易系统及其交易方法，其主要是将至少一数字商品在一内容下载中心进行加密处理以成为一加密数字商品，而加密数字商品将以实际的储存器传递线路以直接送到至少一内容下载点中，当消费者选定一欲购买数字商品时，可持一内容下载卡至其中一内容下载点，利用一实体传输线路直接储存所欲购买的加密数字商品，并藉由一网络传输线路以连接内容下载中心，内容下载中心将根据卡号识别码以产生一卡号解密资料，并将卡号解密资料下载至内容下载卡，当消费者欲使用欲购买数字商品时，即可将内容下载卡置入一内容卡片阅读机中，而内容卡片阅读机将根据卡号识别码以还原卡号解密资料及加密数字商品，以产生可供读取使用的数字商品。

Associated Northcliffe Digital, an arm of the media group that runs the Daily Mail newspaper, is rolling out a string of town-oriented websites.

运营每日邮报的报业集团的一个分支。Associated Northcliffe Digital ，正在推出一系列以小镇为中心内容的网站。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了