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小波变换可以将音频边缘信息完整提出,利用边缘掩蔽水印信息,使水印算法具有透明 性,基于此提出了一种基于离散小波变换的数字音频水印算法,该算法将能代表更多版权信息的 二维图像信息经过 Arnold置乱变换,嵌入到音频小波变换域的低频系数中.并将该算法与已有 的离散余弦( DCT)水印算法相比较,发现该算法在抵抗剪切、加噪、滤波及压缩攻击方面要优于 DCT水印算法.

针对酒后驾车导致交通事故频繁发生的现象,设计了一种驾驶员酒精超标测控电路。该电路由酒气检测、模数转换、单片机最小系统、LCD显示、声光报警、继电器、电源等电路组成。软件用C语言编程,在keil环境中编译。硬件电路在PROTEOUS环境中仿真,通过后将下载程序的单片机和其它有关元器件焊接在PCB板上,上电,酒气检测电路可检测酒精浓度,可语音播报浓度未超标、偏高和超标,液晶屏可显示酒精浓度,当酒精传感器检测的酒精浓度超标时,该电路可自动切断汽车点火系统电源,使汽车无法启动。

WPF编程宝典：使用C# 2012和.NET 4.5 第4版 ；高清扫描PDF与源码 打包一起的

从本单位实际工作需要出发,利用Visual Basic6.0语言进行程序设计,实现对纯数字编码格式的气象报文进行文字格式的翻译转换,使预报报文在实际业务工作中使用更为方便。

在严格定义单成分信号瞬时频率的前提下，综合性地定义了复杂信号的瞬时频率，并给出了计算方法．

使用光子晶体能带结构和等频面(EFS)方法对二维光子晶体中的负折射现象进了研究和仿真．得到了二维光子晶体中出现负折射率现象的频率范围．使用时域有限差分法(FDTD)对光波在二维光子晶体界面和晶体中的传播进行了数值仿真研究．由仿真结果发现在一定的频率范围内，在二维光子晶体中确实可以发现光波的负折射传播现象．

介绍了C/A码、L2C码以及L5码的生成方式、测距精度及特性，并对GPS系统中测距码的扩充作了简要介绍。

SQL Server 2012 integration services高级教程 第2版 PDF电子书下载 带书签目录 完整版

Device drivers make it possible for your software to communicate with your hardware, and because every operating system has specific requirements, driver writing is nontrivial. When developing for FreeBSD, you’ve probably had to scour the Internet and dig through the kernel sources to figure out how to write the drivers you need. Thankfully, that stops now. In FreeBSD Device Drivers, Joseph Kong will teach you how to master everything from the basics of building and running loadable kernel modules to more complicated topics like thread synchronization. After a crash course in the different FreeBSD driver frameworks, extensive tutorial sections dissect real-world drivers like the parallel port printer driver. You’ll learn: * All about Newbus, the infrastructure used by FreeBSD to manage the hardware devices on your system * How to work with ISA, PCI, USB, and other buses * The best ways to control and communicate with the hardware devices from user space * How to use Direct Memory Access (DMA) for maximum system performance * The inner workings of the virtual null modem terminal driver, the USB printer driver, the Intel PCI Gigabit Ethernet adapter driver, and other important drivers * How to use Common Access Method (CAM) to manage host bus adapters (HBAs) Concise descriptions and extensive annotations walk you through the many code examples. Don’t waste time searching man pages or digging through the kernel sources to figure out how to make that arcane bit of hardware work with your system. FreeBSD Device Drivers gives you the framework that you need to write any driver you want, now.