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播放器的c语言程序，通过读取音长基数的值，确定发音的频率，然后按频率值发出歌曲的音调。-Player of the c language program, read through the duration of the base value, to determine the frequency of pronunciation, then issued by the frequency of the pitch songs.

说明：  基于单片机的无线防盗报警器的设计，文档供参考。(The design of wireless anti-theft alarm based on MCU, the document for reference.)

RacorX8 是DirectX的例子程序-RacorX8 are examples of procedures DirectX

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)

一个简单的管理程序-a simple management process

Delphi进程内存信息读取程序，类似于进程管理器的功能，可读取系统进程的内存使用情况，还可对指定内存进行简单修改。程序在编写时没有使用Delphi以外的三方控件，因此编译方便，Delphi7环境的都可直接编译源码。

java code for interpolation this is the short progaram for working

ANSYS单元的中文翻译,详细介绍了各单元的用途.-Chinese translation of ANSYS element, setting out in detail the use of the unit.

碰撞检测（用蒙特卡洛法对目标命中概率进行仿真分析）-Collision detection (using Monte Carlo simulation on the target hit probability analysis)

说明：  二叉树运用，简单背包问题，是本人初学数据结构的作业，(Bintree use, simple knapsack problem, is my data structure beginner operations,)