Based-on-parallel-beam-FBP-algorithm

DistMesh giving a singular FEM matrix?(Hi Anyone here with some experience of using DistMesh in finite element code? I m solving the scalar Helmoltz equation in an annular region in 2D: rho_1 < rho < rho_2 where rho_1 is the radius of a Perfect Electric Conducting cylinder and rho_2 is where the mesh is truncated using an Absorbing Boundary condition. Now, I ve written code to mesh the region myself (by dividing the region into annular rings and picking a fixed number of points on each ring) and I ve written another program which uses DistMesh to mesh the region. I get a nice solution using my own meshing code but the FEM matrix becomes singular when I use DistMesh. This is the DistMesh Code I used: Circle with hole rABC=1.5 rCyl=0.5 fdstring=sprintf( ddiff(dcircle(p,0,0, f),dcircle(p,0,0, f)) ,rABC,rCyl) fd=inline(fdstring, p ) box=[-2,-2 2,2] [p,N]=distmesh2d(fd,@huniform,0.04,box,[]) I tried changing box and the 0.04 value (initial edge length). But every time, the matrix becomes sin)

SPN的差分密码分析，建议选取的明密文对数量为8000+，太小可能结果有偏差(SPN Differential cryptanalysis, ciphertext clear recommendations for selected number of 8000+, too small deviations may result)

SimGear是飞行模拟项目FlightGear的引擎，是一套开源库。(SimGear is FlightGear flight simulator project engine, is a set of open source libraries.)

粒子群算法优化BP神经网络，使用matlab平台实现，解决了BP神经网络速度较慢的问题(Particle swarm optimization (PSO) optimization of BP neural network)

说明：  辨识参数，进行迭代计算，可以辨识各种经典模型的是参数，经典最小二乘法a(Parameter identification, iterative calculation, can identify all kinds of classical models is the parameter, classical least square method a)

This is a code for AODV Routing. It works with matlab. Enjoy it.

DBSCAN Designed by Dr. Michal aszykowski Department of Chemometrics Institute of Chemistry, The University of Silesia. It s the basic one.

ide86.rar单位脉冲，单位阶跃，正弦函数等连续信号的MATLAB表达式。.. (ide86.rar pulse units, unit step, Sine function as a continuous signal MATLAB expression. ..)

基于matlab开发环境，编写了边缘检测的图形识别小程序。用于圆形标点。要求标点为白底黑圆。适合初学者理解图形识别的原理。(Based on the matlab platform，we compile the short program to realize the detection of edge detection algorithm 。For the laymen，it maybe useful。)

Using SA as an Optimization for IMRT.doc