教学点播(EOD)的SOCP子空间模型与实现

总结了教学点播的概念,分析了目前教学点播研究中存在的问题。在对教学活动原型深入分析的基础上,提出了教学点播的SOCP子空间模型,概括了SOCP子空间模型的设计目标,详细介绍了SOCP子空间模型实现的总体架构和各个子空间的实现技术。最后叙述了在目前教学点播实现的基础上进一步的工作设想。     

构件模板动态实例化技术的研究与应用

本文介绍了构件体系结构下的模板动态实例化技术,该技术将构件模板与补充语义分离处理,引入动态实例化操作,为需求改变的动态配置提供了实用和有效的手段。     

PDUIMS--基于持久存储的用户界面管理系统的设计与应用

用户界面作为软件系统的重要组成部分,在软件整个生命周期中具有独特的地位。软件质量控制的核心在于用户界面的有效、可扩展、高适应度的管理、常规的界面管理位于源码一级,对于大规模企业级应用将带来许多弊端文中介绍了一个利用动态加载和持久存储实现的面向商务处理的用户界面管理系统ＰＤＵＩＭＳ,该系统通过功能描述数据表存储用户界面实现了集中统一的数据库工程化界面管理和发布,对于应用语义提供了分离机制实例表明了该     

抽水蓄能机组水泵水轮机模型测试

针对国内首次抽水蓄能电站水泵水轮机组第三方试验台同台对比试验,进行了水轮机模 型测试方法的改进,解决了水泵水轮机四象限试验、瞬时工况点数据采集、水泵大流量工况压力 面空泡观测等试验技术难点。模型试验取得了理想的效果:效率试验的测试不准确度小于 士0. 2 %,试验工况稳定、数据重复性好,采集的“S”特性区和反水泵区的数据点密集。此次试验 表明,国内试验台有能力完成抽水蓄能水泵水轮机组的模型验收试验,对推动我国抽水蓄能电站 的建设有积极意义。     

SCM435钢的相变模型

利用热模拟仪对SCM435钢进行了连续冷却转变曲线(CCT曲线)的测定,并用显微镜观察及统计其室温组织.利用Or-igin软件对实验数据进行处理,根据SCM435不同冷速下的相变及相变转变量,进行铁素体、珠光体、贝氏体、马氏体相变模型的回归.并精确地建立了相变点温度-冷却速率关系模型及相变量-冷却速率关系模型,回归计算得到该钢种的最优模型系数.最后对比了SCM435钢的实验值和回归曲线,结果表明计算值与实验值吻合较好,证明所建立模型的合理性及数据处理方法的可行性,因此可以根据回归结果对实际生产中的真实冷却速率做出实时反应,便于对生产进行更加准确地控制.     

二甲基硫醚与过氧化氢反应机理的研究及溶剂效应

采用密度泛函理论的B3LYP方法,在6-311+G(d,p)基组水平上研究了CH3SCH3与H2O2的微观反应机理,全参数优化了反应势能面上各驻点的几何构型,振动分析和内禀反应坐标(IRC)分析结果证实了中间体和过渡态的真实性,计算所得的键鞍点电荷密度的变化情况也确认了反应过程.结果表明,反应共分2步进行,主要经历了O对S的进攻、H转移以及O-O键断裂的历程.并分别考察了其在水中和甲苯的溶剂效应.结果表明,溶剂效应降低了反应的活化能,并使过渡态红外光谱蓝移.     

Surface-initiated nitroxide-mediated radical polymerization of 2-(dimethylamino)ethyl acrylate on polymeric microspheres

2-(Dimethylamino)ethyl acrylate (DMAEA) was grafted from the surface of alkoxyamine-functionalized crosslinked poly(styrene-co-chloromethylstyrene) microspheres by nitroxide-mediated radical polymerization (NMRP). Latex particles (∼60 nm diameter) bearing chloromethyl groups were synthesized by emulsion polymerization. N-tert-butyl-N-(1-diethyl phosphono-2,2-dimethylpropyl)nitroxide (SG1) was then immobilized on the particle surface. Microspheres grafted with the homopolymer pDMAEA, as well as block copolymers poly(styrene-b-DMAEA) and poly(butyl acrylate-b-DMAEA) were prepared by surface-initiated NMRP in N,N-dimethylformamide at 112 °C, with the addition of free SG1 to ensure that control is maintained. Particle size increases with number average molecular weight (M_n) of untethered polymers. The polymerizations exhibit linear first order kinetic plots and slight curvature of evolution of M_n with conversion. The functional microspheres were analyzed by infrared spectroscopy, transmission electron microscopy and thermal analysis, as well as their dispersibility in water; the results support the formation of surface-grafted pDMAEA on the microspheres.     

Microstructure and mechanical behavior of AlSiCuMgNi piston alloys reinforced with TiB2 particles

AlSiCuMgNi piston composites reinforced with in-situ TiB₂ particles were fabricated by mixing salts reaction process successfully. Microstructures of the composites were observed by mean of scanning electron microscope (SEM) and transmission electron microscope (TEM). X-ray diffraction (XRD) was used to identify the phases in the composites. TiB₂ reinforcement grows in equiaxed or near equiaxed shape and the interfaces between reinforcements and matrix are clear. Compared with the matrix alloys, the composites show an obvious aging peak and an incubation time in the hardness. The aging is accelerated in the composites reinforced with TiB₂. At room temperature, the ultimate tensile strength (UTS) of the composites increases as the percentage of TiB₂ reinforcement increases. When the temperature is beyond 250°C, the ultimate tensile strength of the piston composites decreases sharply. The fracture surfaces of the piston composites are analyzed.     

Comparison of structural and photoluminescence properties of ZnO thin films grown by pulsed laser deposition and ultrasonic spray pyrolysis

ZnO thin films have been deposited by pulsed laser deposition (PLD) and ultrasonic spray pyrolysis (USP) method, respectively. X-ray diffraction and transmission electron microscopy characterizations indicate that ZnO film grown by PLD exhibits better crystallinity than that grown by USP. Photoluminescence spectra show that the near-band edge ultraviolet emission of film grown by PLD is narrower and shifts to higher energy, compared with that of film grown by USP. In the visible range, ZnO film grown by PLD exhibits four local level emission centered at 470 nm, 486 nm, 544 nm, and 613 nm, respectively, while the film grown by USP only presents a weak broad band emission centered at 502 nm. Hall measurement shows higher carrier density and lower hall mobility in ZnO film grown by PLD than that in film grown by USP. The higher density of intrinsic defects as well as higher crystallintiy is considered to account for the difference of photoluminescence in ZnO film grown by PLD with that in film grown by USP.     

VxWorks 实时操作系统在无线通信设备中的应用

描述了将实时操作系统应用到无线通信领域，利用了VxWorks优异的实时性和多任务调度机制，实现了信令板对各个电路的实时控制，给出了基于VxWorks的实时控制软件设计与开发的过程。最后对该系统进行了性能测试分析并与以前的单任务控制系统进行了性能比较，充分说明了VxWorks实时操作系统被应用于无线通信领域中的优异性。