代入法的启发示搜索 我的代码实现是:按照自然语言各字母出现频率的大小从高到低(已经有人作国统计分析了)先生成一张字母出现频率统计表(A)--------(e),(t,a,o,i,n,s,h,r),(d,l),(c,u,m,w,f,g,y,p,b),(v,k,j,x,q,z) ,再对密文字母计算频率,并按频率从高到低生成一张输入密文字母的统计表(B),通过两张表的对应关系,不断用A中的字母去替换B中的字母,搜索不成功时就回退,在这里回朔是一个关键。
上传时间: 2015-10-24
上传用户:wanqunsheng
TLV1544与TMS320VC5402通过串行口连接,此时,A/D转换芯片作为从设备,DSP提供帧同步和输入/输出时钟信号。TLV1544与DSP之间数据交换的时序图如图3所示。 开始时, 为高电平(芯片处于非激活状态),DATA IN和I/OCLK无效,DATAOUT处于高阻状态。当串行接口使CS变低(激活),芯片开始工作,I/OCLK和DATAIN能使DATA OUT不再处于高阻状态。DSP通过I/OCLK引脚提供输入/输出时钟8序列,当由DSP提供的帧同步脉冲到来后,芯片从DATA IN接收4 b通道选择地址,同时从DATAOUT送出的前一次转换的结果,由DSP串行接收。I/OCLK接收DSP送出的输入序列长度为10~16个时钟周期。前4个有效时钟周期,将从DATAIN输入的4 b输入数据装载到输入数据寄存器,选择所需的模拟通道。接下来的6个时钟周期提供模拟输入采样的控制时间。模拟输入的采样在前10个I/O时钟序列后停止。第10个时钟沿(确切的I/O时钟边缘,即上升沿或下降沿,取决于操作的模式选择)将EOC变低,转换开始。
上传时间: 2014-12-05
上传用户:yepeng139
《多传感器数据融合手册》 《Handbook of Multisensor Data Fusion》 作者: David L. Hall 定价: USD 199.95 出版社: CRC 出版年: 2001-06-20 简介 · · · · · · Multisensor data fusion is an emerging technology with important applications in both the military and civilian sectors, such as target recognition, robotics, medical diagnostics, and "smart" buildings. It draws on techniques from wide-ranging disciplines, including artificial intelligence, pattern recognition, and statistical estimation. This handbook is an up-to-date, comprehensive resource for data fusion system designers and researchers. Top experts in the field lead readers from a basic introduction and survey of data fusion technology to advanced mathematics and theory and to some very practical advice for systems implementers.
标签: L. Multisensor Handbook 199.95
上传时间: 2014-02-06
上传用户:二驱蚊器
The 74ALVC16245(74ALVCH16245) is a 16-bit transceiver featuring non-inverting 3-State bus compatible outputs in both send and receive directions.
标签: 16245 non-inverting transceiver featuring
上传时间: 2013-12-21
上传用户:风之骄子
Jitter is extremely important in systems using PLL-based clock drivers. The effects of jitter range from not having any effect on system operation to rendering the system completely non-functional. This application note provides the reader with a clear understanding of jitter in high-speed systems. It introduces the reader to various kinds of jitter in high-speed systems, their causes and their effects, and methods of reducing jitter. This application note will concentrate on jitter in PLL-based frequency synthesizers.
标签: extremely PLL-based important drivers
上传时间: 2014-11-25
上传用户:asddsd
C++Primer中文版 第三版 深入系列 Primer 第三版 著 中中文文版版潘爱民张丽译 Addison-Wesley 中国电力出版社 www.infopower.com.cn Stanley B Lippman J o s é e L a j o i e
标签: Primer Addison-Wesley infopower www
上传时间: 2014-01-14
上传用户:myworkpost
UC Library Extensions UnderC comes with a pocket implementation of the standard C++ libraries, which is a reasonably faithful subset. This documentation describes those UnderC functions and classes which are not part of the C++ standard. UC Library Builtin functions: Most of these are standard C functions, but there are a few unique to the UnderC system which give you runtime access to the compiler. You may evaluate expressions, execute commands, compile code, etc. * Expands the text in expr using the UnderC preprocessor, putting the result into buff. void uc_macro_subst(const char* expr, char* buff, int buffsize) * Executes a UC #-command, like #l or #help. uc_cmd() expects the name of the command, _without_ the hash, e.g. uc_cmd("l fred.cpp") or uc_cmd("help"). void uc_cmd(const char* cmd) * Evaluates any C++ expression or statement will return non-zero if unsuccessful.
标签: implementation Extensions libraries standard
上传时间: 2013-12-14
上传用户:leehom61
This library allows creating, modifying and extracting zip archives in the compatible way with PKZIP (2.5 and higher) and WinZip. Supported are all possible operations on the zip archive: creating, extracting, adding, deleting files from the archive, modifications of the existing archive. There is also the support for creating and extracting multiple disk archives (on non-removable devices as well) and for password encryption and decryption. This module uses compression and decompression functions from zlib library by Jean-loup Gailly and Mark Adler.
标签: compatible extracting modifying creating
上传时间: 2014-12-22
上传用户:chfanjiang
This paper examines the asymptotic (large sample) performance of a family of non-data aided feedforward (NDA FF) nonlinear least-squares (NLS) type carrier frequency estimators for burst-mode phase shift keying (PSK) modulations transmitted through AWGN and flat Ricean-fading channels. The asymptotic performance of these estimators is established in closed-form expression and compared with the modified Cram`er-Rao bound (MCRB). A best linear unbiased estimator (BLUE), which exhibits the lowest asymptotic variance within the family of NDA FF NLS-type estimators, is also proposed.
标签: performance asymptotic examines non-data
上传时间: 2015-12-30
上传用户:225588
In this article, we present an overview of methods for sequential simulation from posterior distributions. These methods are of particular interest in Bayesian filtering for discrete time dynamic models that are typically nonlinear and non-Gaussian. A general importance sampling framework is developed that unifies many of the methods which have been proposed over the last few decades in several different scientific disciplines. Novel extensions to the existing methods are also proposed.We showin particular how to incorporate local linearisation methods similar to those which have previously been employed in the deterministic filtering literature these lead to very effective importance distributions. Furthermore we describe a method which uses Rao-Blackwellisation in order to take advantage of the analytic structure present in some important classes of state-space models. In a final section we develop algorithms for prediction, smoothing and evaluation of the likelihood in dynamic models.
标签: sequential simulation posterior overview
上传时间: 2015-12-31
上传用户:225588