便携式B型超声诊断仪具有无创伤、简便易行、相对价廉等优势，在临床中越来越得到广泛的应用。它将超声波技术、微电子技术、计算机技术、机械设计与制造及生物医学工程等技术融合在一起。开展该课题的研究对提高临床诊断能力和促进我国医疗事业的发展具有重要的意义。 便携式B型超声诊断仪由人机交互系统、探头、成像系统、显示系统构成。其基本工作过程是：首先人机交互系统接收到用户通过键盘或鼠标发出的命令，然后成像系统根据命令控制探头发射超声波，并对回波信号处理、合成图像，最后通过显示系统完成图像的显示。 成像系统作为便携式B型超声诊断仪的核心对图像质量有决定性影响，但以前研制的便携式B型超声诊断仪的成像系统在三个方面存在不足：第一、采用的是单片机控制步进电机，控制精度不高，导致成像系统采样不精确；第二、采用的数字扫描变换算法太粗糙，影响超声图像的分辨率；第三、它的CPU多采用的是51系列单片机，测量速度太慢，同时也不便于系统升级和扩展。 针对以上不足，提出了基于FPGA的B型超声成像系统解决方案，采用Altera公司的EP2C5Q208C8芯片实现了步进电机步距角的细分，使电机旋转更匀速，提高了采样精度；提出并采用DSTI-ULA算法（Uniform Ladder Algorithm based on Double Sample and Trilinear Interotation）在FPGA内实现数字扫描变换，提高了图像分辨率；人机交互系统采用S3C2410-AL作为CPU，改善了测量速度和系统的扩展性。 通过对系统硬件电路的设计、制作，软件的编写、调试，结果表明，本文所设计的便携式B型超声成像系统图像分辨率高、测量速度快、体积小、操作方便。本文所设计的便携式B型超声诊断仪可在野外作业和抢险（诸如地震、抗洪）中发挥作用，同时也可在乡村诊所中完成对相关疾病的诊断工作。
上传时间： 2013-05-18
上传用户：helmos
针对目前使用的RS232接口数字化B超键盘存在PC主机启动时不能设置BIOS，提出一种PS2键盘的设计方法。基于W78E052D单片机，采用8通道串行A/D转换器设计了8个TGC电位器信息采集电路，电位器位置信息以键盘扫描码序列形式发送，正交编码器信号通过XC9536XL转换为单片机可接收的中断信号，软件接收到中断信息后等效处理成按键。结果表明，在满足开机可设置BIOS同时，又可实现超声特有功能，不需要专门设计驱动程序，接口简单，成本低。 Abstract: Aiming at the problem of the digital ultrasonic diagnostic imaging system keyboard with RS232 interface currently used couldn?蒺t set the BIOS when the PC boot， this paper proposed a design method of PS2 keyboards. Based on W78E052D microcontroller，designed eight TGC potentiometers information acquisition circuit with 8-channel serial A/D converter， potentiometer position information sent out with keyboard scan code sequentially.The control circuit based on XC9536 CPLD is used for converting the mechanical actions of the encoders into the signals that can be identified by the MCU， software received interrupt information and equivalently treatmented as key. The results show that the BIOS can be set to meet the boot， ultrasound specific functionality can be achieved at the same time， it does not require specially designed driver，the interface is simple and low cost.
上传时间： 2013-10-10
上传用户：asdfasdfd
排序算法、字典和B-树的C++语言实现 代码内容 包括以下算法： qui.c sort: quicksort qsort.c sort: qsort ins.c sort: insert sort shl.c sort: shell sort has.c dictionary: hash tables bin.c dictionary: binary tree rbt.c dictionary: red-black trees skl.c dictionary: skip lists ext.c external sort btr.c btree 语言 C++ 编译平台 Visual C++ 作者 Thomas Niemann 备注 来自Sorting and Searching Algorithms:A Cookbook
标签： sort qsort quicksort insert
上传时间： 2013-12-15
上传用户：silenthink
See Appendix B for a description of the programs included on this companion disk. RESOURCE.WRI identifies other books and resources for Internet programming. WEBHELP.HLP contains an introduction to the World Wide Web. TCPMAN.HLP provides detailed instructions to help you use the Trumpet Winsock included on this disk. Use the Program Manager s File menu Run option to execute the SETUP.EXE program found on this disk. SETUP.EXE will install the programs on your hard drive and create an Internet Programming group window. Internet编程技术 [配套程序] [涉及平台] VC [作者] void [文件大小] 1032K
标签： description companion Appendix RESOURCE
上传时间： 2013-12-04
上传用户：asasasas
This project attempts to implement a Database using B+Tree. The project has developed a DATABASE SYSTEM with lesser memory consumption. Its API includes simple SQL Statements and the output is displayed on the screen. Certain applications for which several features of existing databases like concurrency control, transaction management, security features are not enabled. B+Trees can be used as an index for factor access to the data. Help facility is provided to know the syntax of SQL Statements.
标签： project implement developed Database
上传时间： 2013-12-25
上传用户：semi1981
* "Copyright (c) 2006 Robert B. Reese ("AUTHOR")" * All rights reserved. * (R. Reese, reese@ece.msstate.edu, Mississippi State University) * IN NO EVENT SHALL THE "AUTHOR" BE LIABLE TO ANY PARTY FOR * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE "AUTHOR" * HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
上传时间： 2015-09-24
上传用户：mpquest
Verilog HDL: Magnitude For a vector (a,b), the magnitude representation is the following: A common approach to implementing these arithmetic functions is to use the Coordinate Rotation Digital Computer (CORDIC) algorithm. The CORDIC algorithm calculates the trigonometric functions of sine, cosine, magnitude, and phase using an iterative process. It is made up of a series of micro-rotations of the vector by a set of predetermined constants, which are powers of two. Using binary arithmetic, this algorithm essentially replaces multipliers with shift and add operations. In a Stratix™ device, it is possible to calculate some of these arithmetic functions directly, without having to implement the CORDIC algorithm.
标签： representation Magnitude the magnitude
上传时间： 2013-12-24
上传用户：金宜
About: hamsterdb is a database engine written in ANSI C. It supports a B+Tree index structure, uses memory mapped I/O (if available), supports cursors, and can create in-memory databases. Release focus: Major feature enhancements Changes: This release comes with many changes and new features. It can manage multiple databases in one file. A new flag (HAM_LOCK_EXCLUSIVE) places an exclusive lock on the file. hamsterdb was ported to Windows CE, and the Solution file for Visual Studio 2005 now supports builds for x64. Several minor bugs were fixed, performance was improved, and small API changes occurred. Pre-built libraries for Windows (32-bit and 64-bit) are available for download. Author: cruppstahl
标签： C. hamsterdb structure database
上传时间： 2013-12-11
上传用户：LouieWu
ITU-T G.729语音压缩算法。 description: Fixed-point description of commendation G.729 with ANNEX B Coding of Speech at 8 kbit/s using Conjugate-Structure Algebraic-Code-Excited Linear-Prediction (CS-ACELP) with Voice Activity Decision(VAD), Discontinuous Transmission(DTX), and Comfort Noise Generation(CNG).
标签： description commendation Fixed-point 729
上传时间： 2014-11-23
上传用户：thesk123
The Original USB 2.0 specification released on April 27, 2000 Errata to the USB 2.0 specification as of December 7, 2000 Mini-B connector Engineering Change Notice to the USB 2.0 specification. Pull-up/pull-down Resistors Engineering Change Notice to the USB 2.0 specification. Errata to the USB 2.0 specification as of May 28, 2002 Interface Association Descriptor Engineering Change Notice to the USB 2.0 specification. Rounded Chamfer Engineering Change Notice to the USB 2.0 specification as of October 8, 2003 Unicode Engineering Change Notice to the USB 2.0 specification as of February 21, 2005 Inter-Chip USB Supplement Revision 1.0 as of March 13, 2006 Revision 1.3 of the USB On-The-Go Supplement as of December 5, 2006 Revision 1.01 of the Micro-USB Cables and Connectors Specification as of April 4, 2007 USB 2.0 Link Power Management Addendum Engineering Change Notice to the USB 2.0 specification as of July 16, 2007.
标签： specification 2.0 USB Original
上传时间： 2013-12-31
上传用户：familiarsmile
