武汉理工大学通信13级单片机应用实习

单片微型计算机简称单片机，又称为微型控制器，是微型计算机的一个重要分支。随着电子技术的发展，大规模及超大规模集成电路和制造工艺的进一步提高，单片机以其高可靠性、高性价比、低电压、低功耗等一系列优点，广泛应用于控制系统、数据采集系统、智能化仪器表等领域。单片机最小系统电路板在单片机开发市场和大学生电子设计方面十分流行。本次课程设计包括STC89S52单片机最小系统包括复位和时钟电路及供电系统、4×4矩阵键盘、6个7段LED数码管显示电路以及MAX232和RS-232标准串口构成的串口通信电路。利用相关设计软件（Altium Designer）进行原理图设计，利用Keil软件编程，利用Proteus软件仿真，借此巩固单片机应用、模拟电路、数字电路课程及学会各种工程软件的使用。 本次实习完成了单片机最小系统及扩展电路的设计、焊接、调试，完成了ISP下载电路的设计、焊接，实现了数据输入、数据显示、串口通信三大功能，完成了实习任务要求，可以在自己设计的单片机最小系统硬件上实现实习要求的所有功能。

Oracle11g数据库入门第5章 事务管理 并发控制

事务基本概念 并发控制概述 事务隔离级别 事务调度 锁 基于时间戳的并发控制 多版本读一致性的含义 小结

Oracle11g数据库入门第6章 锁

什么是锁？ 锁定问题 丢失更新 悲观锁定 乐观锁定 乐观锁定还是悲观锁定？ 阻塞 死锁 锁升级

Oracle11g数据库入门第5章 后台进程

服务器进程 专用服务器连接 共享服务器连接 连接与会话 专用服务器与共享服务器 后台进程 中心后台进程 工具后台进程

Oracle11g数据库入门第4章

进程全局区（Process Global Area，PGA） 用户全局区（User Global Area，UGA） 系统全局区（System Global Area，SGA） 固定SGA 重做缓冲区 块缓冲区缓存 共享池 大池 Java池 自动SGA内存管理 自动内存管理 小结

清华大学出版社Oracle11g数据库第3章

参数文件 什么是参数？ 遗留的init.ora参数文件 服务器参数文件 数据文件 段（segment） 区段（extent） 块（block） 表空间 存储层次体系小结 重做日志文件 在线重做日志 归档重做日志

Oracle11g数据库第一章

清华大学出版社Oracle11g数据库最佳入门 第一章数据库概述

GIS_and_Spatial_Analytical_Problems

lncreasingly, methods of spatial analysis are being integrated within eeographical information systems. As this integration occurs, it is important to ensure that, (i) users of GIS recognize the limitations of spatial analysis, (ii) researchers continue to work on removing the existing impediments to iccurate spatial analysis, and (iii) developers of GIS consider these limitations. In this article we discuss eight general impediments that arise in spatial analyses that span a diverse range of substantive applications. Geographical information systemi offer not orrly the opportunity to integrate various methods of spatial analysis, but also the chance to learn more about the underlying impediment

A Novel Method of Buffer Generation Based on Vector Boundary Tracing

Utilizing the property that the distances from all points located on the borderline of buffer zone to corresponding buffer target are the same, this paper presents a novel method of buffer generation based on vector boundary tracing. The new method can avoid complex vector calculations, such as line and curve segment intersection, clipping and recombination, the closure of borderline and so on, and also has an advantage of high precision the same as all existing vector-based algorithms. The main steps of this algorithm include: (1) Generate the initial tracing point set located on the borderline of buffer zone; (2) Obtain an integrated and closed borderline by tracing these points; (3) Construct the area targets on the basis of these losed borderlines. The test results and analysis indicate that this algorithm has a great advantage in the aspects of decreasing EMS memory consumption and improving calculation accuracy, and its computational efficiency can fully meet the demand of usual application in GIS. Furthermore, the principle of boundary tracing in the algorithm has a potential for further being promoted and used to design related spatial analysis algorithms.

An Effective Buffer Generation Method in GIS

Buffer Analysis is one of the most important functions of spatial analysis in GIS. This paper uses rotation transform point formula and recursion method to further improve on the vector buffer generation algorithm of d ouble parallel lines and circular arcs, simplifies the process of the generation of parallel lines and the circular correction of sharp angles, and finds a better solution to intersection problem of borderlines of buffer zone.