便攜式B型超聲診斷儀具有無創傷、簡便易行、相對價廉等優勢，在臨床中越來越得到廣泛的應用。它將超聲波技術、微電子技術、計算機技術、機械設計與制造及生物醫學工程等技術融合在一起。開展該課題的研究對提高臨床診斷能力和促進我國醫療事業的發展具有重要的意義。 便攜式B型超聲診斷儀由人機交互系統、探頭、成像系統、顯示系統構成。其基本工作過程是：首先人機交互系統接收到用戶通過鍵盤或鼠標發出的命令，然后成像系統根據命令控制探頭發射超聲波，并對回波信號處理、合成圖像，最后通過顯示系統完成圖像的顯示。 成像系統作為便攜式B型超聲診斷儀的核心對圖像質量有決定性影響，但以前研制的便攜式B型超聲診斷儀的成像系統在三個方面存在不足：第一、采用的是單片機控制步進電機，控制精度不高，導致成像系統采樣不精確；第二、采用的數字掃描變換算法太粗糙，影響超聲圖像的分辨率；第三、它的CPU多采用的是51系列單片機，測量速度太慢，同時也不便于系統升級和擴展。 針對以上不足，提出了基于FPGA的B型超聲成像系統解決方案，采用Altera公司的EP2C5Q208C8芯片實現了步進電機步距角的細分，使電機旋轉更勻速，提高了采樣精度；提出并采用DSTI-ULA算法（Uniform Ladder Algorithm based on Double Sample and Trilinear Interotation）在FPGA內實現數字掃描變換，提高了圖像分辨率；人機交互系統采用S3C2410-AL作為CPU，改善了測量速度和系統的擴展性。 通過對系統硬件電路的設計、制作，軟件的編寫、調試，結果表明，本文所設計的便攜式B型超聲成像系統圖像分辨率高、測量速度快、體積小、操作方便。本文所設計的便攜式B型超聲診斷儀可在野外作業和搶險（諸如地震、抗洪）中發揮作用，同時也可在鄉村診所中完成對相關疾病的診斷工作。
針對目前使用的RS232接口數字化B超鍵盤存在PC主機啟動時不能設置BIOS，提出一種PS2鍵盤的設計方法。基于W78E052D單片機，采用8通道串行A/D轉換器設計了8個TGC電位器信息采集電路，電位器位置信息以鍵盤掃描碼序列形式發送，正交編碼器信號通過XC9536XL轉換為單片機可接收的中斷信號，軟件接收到中斷信息后等效處理成按鍵。結果表明，在滿足開機可設置BIOS同時，又可實現超聲特有功能，不需要專門設計驅動程序，接口簡單，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.
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編程技術 [配套程序]
[涉及平臺] VC
[作者] void
[文件大小] 1032K
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.
* "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.
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.
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
ITU-T G.729語音壓縮算法。
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).
