DFIG

Visual basic complete tutorial for connection to db s

双重差分估计 双重差分模型（difference-in-difference，DID）近年来多用于计量经济学中对于公共政策或项目实施效果 的定量评估。 通常大范围的公共政策有别于普通科研性研究，难以保证对于政策实施组和对照组在样本分配上的完全随机。非随机分配政策实施组和对照组的试验称为自然试验（naturaltrial），此类试验存在较显著的特点，即不同组间样本在政策实施前可能存在事前差异，仅通过单一前后对比或横向对比的分析方法会忽略这种差异，继而导致对政策实施效果的有偏估计。(Quantitative evaluation of policy or project implementation effect. Generally, a wide range of public policies is different from general scientific research, and it is difficult to ensure that the sample allocation for the policy implementation group and the control group is completely random. The non-randomly assigned policy implementation group and the control group are called natural trials, which have significant characteristics, i.e. there may be prior differences between the different groups of samples before the implementation of the policy, and this difference will be ignored only through a single pre-and post-comparison or horizontal comparison analysis method, which leads to the policy. Biased estimation of implementation)

微带天线仿真模型，仿真了微带天线的HFSS模型。(Microstrip antenna simulation model)

这是一个弹球的游戏，不过有些粗糙。基本功能还是可以的-This is a pinball game, but some rough. Basic functions can still be the

matlab数字滤波器，cic，hb，fir 滤波器 欢迎参考-Matlab digital filters, cic, hb, welcomed the reference filter fir

说明：  使用matlab语言进行阵列天线的仿真与编程，获得不同阵元的天线阵列的方向图(Using MATLAB language to simulate and program the array antenna, obtain the pattern of different array elements)

迷宫小游戏，其中蓝色为墙壁，白色为可走的路，益智哦-Maze game, in which blue walls, white for roads yizhi Oh

利用拨码开关控制液晶显示器进行十进制数字显示。(DIP switches control the use of liquid crystal display to decimal figures.)

how-to-provide-interactive-editing-for-a-constant-line-e1003-16.1.4-234

c语言实现傅里叶变换，可用于各种谱分析，也可用于dsp下位机的处理(Fourier transform is implemented in C language and can be used in various spectral analysis)