一种智能化的键盘练习器

本文介绍了一个利用单片机研制的键盘操作练习器。它能完成健盘输入练习和输入水平测试二项功能。     

四路激光跟踪测量系统最佳测量区域和系统自标定

研究了系统最佳布局下的最佳测量区域问题,给出了几何精度衰减因子PDOP在三维空间内的变化规律。通过计算机仿真研究了最佳测量布局对系统自标定的影响规律,指出最佳测量布局中的标称配置对系统自标定精度的影响最小,同时这种布局有着最小的几何精度衰减因子。     

基于S-CDMA的HFC上行信道接入协议性能仿真分析

讨论了基于S－CDMA的HFC网上行信道的高效接入协议－SAMA，提出了双信道接入机制的工作原理，并对系统性能进行了分析与计算机仿真，得到一些有意义的结论。     

基于嵌入式计算机和Ethernet的分布式波控系统

介绍一种基于嵌入式计算机和以太网(Ethernet)的相控阵雷达分布式波控系统。整个波控系统以数个嵌入式计算机为核心，通过以太网与雷达的控制计算机通讯。     

基于GMS97C2051的串行多路温度数据采集系统的设计

介绍了一种以GMS97C2051单片机为核心、利用新型集成化智能温度数字传感器DS1621实现的多路温度数据采集系统,利用MAX3232完成电平转换并将采集到的数据通过串行接口传送给上位机,在上位机中实现显示、控制等功能.叙述了DS1621的特性及工作方式,给出了硬件电路原理和软件流程,以及系统与上位机通信程序源代码.该系统实现了现场多点温度数据的采集,明显提高了检测可靠性和检测效率.现场实验证明该系统在测试过程中工作稳定,满足设计要求.     

Deactivation reactions in the modeled 2,2,6,6‐tetramethyl‐1‐piperidinyloxy‐mediated free‐radical polymerization of styrene: A comparative study with the 2,2,6,6‐tetramethyl‐1‐piperidinyloxy/acrylonitrile system

The competitiveness of the combination and disproportionation reactions between a 1‐phenylpropyl radical, standing for a growing polystyryl macroradical, and a 2,2,6,6‐tetramethyl‐1‐piperidinyloxy (TEMPO) radical in the nitroxide‐mediated free‐radical polymerization of styrene was quantitatively evaluated by the study of the transition geometry and the potential energy profiles for the competing reactions with the use of quantum‐mechanical calculations at the density functional theory (DFT) UB3‐LYP/6‐311+G(3df, 2p)//(unrestricted) Austin Model 1 level of theory. The search for transition geometries resulted in six and two transition structures for the radical combination and disproportionation reactions, respectively. The former transition structures, mainly differing in the out‐of‐plane angle of the N? O bond in the transition structure TEMPO molecule, were correlated with the activation energy, which was determined to be in the range of 8.4–19.4 kcal mol^?1 from a single‐point calculation at the DFT UB3‐LYP/6‐311+G(3df, 2p)//unrestricted Austin Model 1 level. The calculated activation energy for the disproportionation reaction was less favorable by a value of more than 30 kcal mol^?1 in comparison with that for the combination reaction. The approximate barrier difference for the TEMPO addition and disproportionation reaction was slightly smaller for the styrene polymerization system than for the acrylonitrile polymerization system, thus indicating that a β‐proton abstraction through a TEMPO radical from the polymer backbone could diminish control over the radical polymerization of styrene with the nitroxide even more than in the latter system. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 232–241, 2007     

利用计算机辅助装调检测矩形大口径离轴非球面的方法研究

通过非球面的零位补偿法,完成了对矩形大口径离轴非球面镜的检测。先用光学设计软件Zemax从理论上分析了在检测中会出现的现象,并结合计算机辅助装调技术,确定在检测过程中相对敏感的自由度,然后控制这些量,使补偿器和非球面的相对关系与理论设计相吻合,在Zygo相位干涉仪上测得最终结果。在λ=632.8nm时,中心圆口径与两个边缘圆口径面形误差RMS分别为0.022λ,0.037λ,0.032λ。检测结果,达到预期目的。     

A Framework for Monitoring Progress and Planning Teaching Towards the Effective Use of Computer Algebra Systems

This article suggests a framework to organise a cluster of variables that are associated with students' effective use of computer algebra systems (CAS) in mathematics learning. Based on a review of the literature and from the authors' own teaching experience, the framework identifies the main characteristics of students' interactions with CAS technology and how these may be used to monitor students' developing use of CAS; from this, the framework may be used to plan teaching in order to gain greater benefit from the availability of CAS. Four case studies describing students' development over a semester are reported. These demonstrate a variety of combinations of technical competencies and personal attributes. They indicate the importance of both the technical and personal aspects but suggest that negative attitudes rather than technical difficulties can limit the effective use of CAS. Finally practical suggestions are given for teaching strategies which may promote effective use of CAS.This revised version was published online in September 2005 with corrections to the Cover Date.     

信息技术与传统实验教学整合的探讨

以HPCI 1型物理实验计算机辅助教学系统为例 ,论述了信息技术和传统实验的结合及新型教学模式的构建     

广播电视发射台技术指标集中自动测试系统

本文介绍了利用计算机技术、网络技术、三遥技术对广播电视发射技术指标进行实时自动测试的系统，以便进一步为安全优质播出提供技术保证。