一种基于社会网络技术的教育协作支持系统设计

为了使用互联网技术更好地促进创新教育,为培养学生创新能力提供有利的环境,设计了一个基于社会网络技术的教育协作支持系统,提出了基于社会网络拓扑结构的相似度概念并以此为基础设计了协作推荐算法。协作推荐算法可以根据学生的兴趣推荐合适的合作伙伴、指导老师、专家、项目或者文档资料。该系统帮助学生更好地应用所学知识解决学习项目,达到创新教育的目的。     

Design of optical strip-loaded waveguides with zero modalbirefringence

Integrated optic devices are usually sensitive to the polarization state of light, because the two polarized modes of the waveguides that form the devices in general have different propagation constants and may also suffer from different losses. The performance of such devices becomes unstable when they are connected to single-mode fibers, as the polarization state of the output light from a practical fiber link usually fluctuates in an unpredictable manner. A simple solution could be provided by using waveguides in which the two polarized modes are degenerate, i.e., have equal propagation constants. In this paper, it is shown theoretically with the spectral index method that the quasi-transverse electric (TE) and quasi-transverse magnetic (TM) modes of a properly designed optical strip-loaded waveguide can have equal propagation constants. The conditions for achieving mode degeneracy, or zero modal birefringence, are presented and discussed. Strip-loaded waveguides with degenerate polarized modes can be used potentially for forming polarization-insensitive optoelectronic devices     

通用可编程自适应机电产品寿命测试系统

应对各国技术壁垒,我国对各类产品的安规认证及安规测试也日益重视.文章介绍了一种基于单片机系统,驱动气动装置和辅助电动装置,能对多种机电产品进行安规寿命测试的通用可编程自适应测试系统.     

球型旋转锉的最简加工

研究了加工球型特种回转面刀具的最简加工理论,这种前所未有的简单方法,是作者多年潜心研究的结果。它无需数控,也无需对机床作任何实质性改动。     

MIDI to SP MIDI transcoding using phrase stealing

The mobile phone industry has a problem with conversion from MIDI to SP-MIDI, which handles specific polyphonic limits. Simple specific polyphonic reduction algorithms, such as note-stealing, may lose or interrupt important musical information. The authors help resolve the problem with a phrase-stealing algorithm that drops the perceptually least important notes and preserves the most important phrases. Tests show that listeners reacted positively to this solution.     

圈条效应的探讨

通过文字和波谱图描述了圈条效应的产生原因和特征,借助立达专家系统对机械波的分析,指出了判别圈条效应的重要性,并阐述了几种运用电子条干仪判别的方法.     

基于级联观测器的多输入多输出非线性系统的故障诊断

将块观测方法应用于非线性系统的故障检测和分离.首先给出了非线性系统的块观测形式,针对传感器故障和执行器故障对非线性系统进行分块,得到了带有故障系统的块观测器形式.利用滑模观测器实现系统状态观测,得到观测器误差;利用所设计的观测器对非线性系统进行故障的诊断和分离;采用等效输出注入概念重构了故障信号,使得多变量输入输出非线性系统的故障诊断问题得到了解耦;针对异步电动机系统实现了传感器故障的分离.仿真结果证明了算法的有效性.     

Synergistic effect of various elements in Fe41Co7Cr15Mo14C15B6Y2 amorphous alloy hollow ball on catalytic degradation of methylene blue

Metallic glasses have recently attracted great attention in terms of degrading dyes and other organic pollutants as an environmentally friendly material for was...     

非晶复合材料的半固态成形技术研究动向

综述了国内外非晶复合材料的制备与成形方法,特别对内生块体非晶复合材料的制备和成形技术的现状进行了分析,对内生块体增塑非晶复合材料半固体成形技术的研究动向进行了详细的介绍。最后,对内生块体非晶复合材料的半固体流变铸造成形技术进行了详细的论述和展望。