基于Qt/Embedded的数码一体机图形界面设计与实现

以数码一体机用户图形操作界面设计与实现为例,阐述了嵌入式Linux下Qt/Embedded的移植.设计、开发并移植了符合要求的GUI应用程序,介绍了在嵌入式Qt/Embedded中如何解决中文显示的问题,同时对系统的设计和实现做了详细说明.     

带电感的PWM调光方法

介绍通过在PWM调光驱动电路中引入电感,达到平均电流的作用。从模拟和实验角度得出了驱动电路中电感大小的确定方法,并深入分析了此驱动电路中LED上电流值和PWM波占空比之间的函数依赖关系,可由计算机通过RS-485对LED亮暗程度实现实时、细致的多档位控制。     

2-(4-甲氧基苯基)亚肼基乙酸与乙醛酸反应密度泛函理论研究

本文应用量子化学密度泛函理论(DFT)研究了2-(4-甲氧基苯基)亚肼基乙酸与乙醛酸的反应机理及动力学行为,并研究了不同取代基对反应的影响.在RB3LYP/6-31G*水平上,优化了各反应通道的反应物、中间体、过渡态及产物的几何构型,计算了各驻点的振动频率、零点能和电荷分布.计算结果表明,该反应有2条反应通道,分别生成(2Z)和(2E)-3(4-甲氧基苯基二氮烯基)丙烯酸.产物发生了键长的平均化和电荷的重新分布.两反应通道具有相同的反应入口,Z式产物为主要产物,2-(4-甲氧基苯基)亚肼基乙酸中苯环对位被给电子基团取代,有利于反应进行.     

杜仲松脂醇二葡萄糖苷含量的近红外光谱检测研究

采用AntarisⅡ傅立叶变换红外光谱分析仪器(Thermo Nicolet)测定了9种杜仲的光谱数据,运用偏最小二乘法(PLS)和主成分分析回归(PCR)分别建立了杜仲中松脂醇二葡萄糖苷(PDG)含量与吸光度变量的近红外光谱定标模型,并对所建模型进行验证.结果表明,2种方法建立的模型精度都较高,其中模型的预测能力强弱指标SSE=2.8333,PRESS=7.2392,可见在近红外光谱下,PCR和PDG都适合对杜仲进行检测研究,这是本文的一个重要结果,为以后杜仲的指标检验研究提供了理论和实验依据:但是,PCR建立的(PDG)定标模型预测精度稍高于偏最小二乘法(PLS)建立的模型,所以文中只对PCR进行模型的建立,PLS方法对杜仲检测分析这个问题有待于以后的进一步讨论和研究.     

大赛评分管理系统开发

在局域网中通过Excel共享工作簿和属性设置,用宏与VBA在Excel中开发大赛评分管理系统,提高工作效率。     

AutoCAD 2000 Visual LISP ActiveX编程技术

Ｖｉｓｕａｌ ＬＩＳＰ不但提供了完全可视化的代码编写、调试环境,而且还可以利用先进的ＡｃｔｉｖｅＸ和事件反应器技术,使其比传统的ＡｕｔｏＬＩＳＰ开发的软件更具智能化、运行更为迅速。对ＡｃｔｉｖｅＸ技术在Ｖｉｓｕａｌ ＬＩＳＰ编程中的应用方法作了详细地介绍并附以相应的应用实例。     

基于Web与组件技术的企业应用系统设计模型

文章介绍了“Browse－WebServe－DBMS”体系结构的三种模式及相关的程序设计技术[1],提出了一个基于Web与组件技术的企业应用系统软件设计模型,开发了一个应用实例,并统计分析了相关数据,说明了基于Web与组件技术的软件设计方法对于提高组件重用率,缩短开发周期,提高开发效率,提高系统的可维护性等具有明显的优势。     

事件运算、事件表达式与主动数据库技术研究

主动数据库系统的主动性源于事件的发生,完整准确地表达事件,是建立事件规则库和事件“监视器”高效工作的关键。该文从事件入手,讨论事件运算规则、事件表达式的构造方法和“事件-条件-动作”（ECA）规则的描述格式。     

Integration of topology and shape optimization for design of structural components

This paper presents an integrated approach that supports the topology optimization and CAD-based shape optimization. The main contribution of the paper is using the geometric reconstruction technique that is mathematically sound and error bounded for creating solid models of the topologically optimized structures with smooth geometric boundary. This geometric reconstruction method extends the integration to 3-D applications. In addition, commercial Computer-Aided Design (CAD), finite element analysis (FEA), optimization, and application software tools are incorporated to support the integrated optimization process. The integration is carried out by first converting the geometry of the topologically optimized structure into smooth and parametric B-spline curves and surfaces. The B-spline curves and surfaces are then imported into a parametric CAD environment to build solid models of the structure. The control point movements of the B-spline curves or surfaces are defined as design variables for shape optimization, in which CAD-based design velocity field computations, design sensitivity analysis (DSA), and nonlinear programming are performed. Both 2-D plane stress and 3-D solid examples are presented to demonstrate the proposed approach. Received January 27, 2000 Communicated by J. Sobieski     

Decentralized robust control of mechanical systems

For mechanical systems described by Euler-Lagrange equations and involving high-order interconnections, this paper proposes a decentralized control, which guarantees the uniform ultimate stability when the control objective is tracking a smooth desired trajectory. The controller design is based on some physical properties of such systems and Lyapunov design methodology. The application of the proposed controller to robot manipulators is presented, and experiment results are included to illustrate the performance of the proposed control algorithm