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matlab codes for MR radial imaging

A polyalphabetic cipher is any cipher based on substitution, using multiple substitution alphabets. The Vigenère cipher is probably the best-known example of a polyalphabetic cipher, though it is a simplified special case.Polyalphabetic substitution ciphers are useful because the are less easily broken by frequency analysis, however if an attacker knows for instance that the message has a period n, then he simply can individually frequency analyze each cipher alphabet. The number of letters encrypted before a polyalphabetic substitution cipher returns to its first cipher alphabet is called its period. The larger the period, the stronger the cipher. Of course, this method of encryption is certainly not secure by any definition and should not be applied to any real-life scenarios.

用于求取一段时间信号序列的求取自相关函数、功率谱密度(Obtaining autocorrelation function for obtaining a period of a signal sequence, power spectral density)

(1) 在某些无线信道中，多普勒频移会引起无线信道输出信号的混叠。请描述产生混叠的各种原因； (2) 无线信道中的多普勒谱有一种经典谱(classic spectrum)，请解释产生这种谱形状的机理； (3) 请用Simulink工具编写代码(S-Function方式)，产生一单径瑞利信道，其多普勒谱为经典谱，其中移动速率为120km/h。并请回答：证明自己用计算机产生的经典谱是正确的可能方法。 ((1) in certain wireless channel, the Doppler frequency shift will be caused by wireless channel output signal aliasing. Please describe the resulting aliasing of a variety of reasons (2) wireless channel Doppler spectrum there is a classical spectrum (classic spectrum), please explain such a spectral shape of the mechanism (3) Please use Simulink tools for writing code ( S-Function mode), resulting in a single Path Rayleigh channel, the Doppler spectrum for the classical spectrum, including mobile rate of 120km/h. And please answer: prove that they used computer-generated classical spectrum is correct possible ways.)

书名：[MATLAB语言常用算法程序集].(龚纯).清晰版 内容：插值，函数逼近，特征值计算，数值微分，数值积分，方程求根，非线性方程组求解，线性方程组的直接法，线性方程组的的迭代法，随机数生成，特殊函数计算，常微分方程的初值问题，偏微分方程的数值解法，数据统计和分析。(Title: [MATLAB algorithms commonly used in assembly language]. (Gong pure). Clearer view of the contents: interpolation, function approximation, eigenvalue calculation, numerical differentiation, numerical integration, finding roots of equations, nonlinear equations, linear equations group, direct, linear equations of the iterative method, random number generation, calculation of special functions, initial value problems for ordinary differential equations, numerical solution of partial differential equations, statistics and analysis.)

EWB DC-DC CONVERTER PROJECT

Very Simple Volume Rendering

Simple exception class used to communicate that the command-line tool should print the usage message.

lmd 采用滑动平均处理，调整过，可以直接运行出图。(lmd hua dong pingjun)

非协作方式下在高斯信道下的MATLAB仿真包括误码率(Non-collaborative approach in the Gaussian channel under the MATLAB simulation, including bit error rate)