降低热对流干燥设备能耗的研究及应用

目的：降低流化床类设备高能耗的方法,提高生产效率。方法：以设备技改前后的干燥水分含量为评价指标,在单因素试验的基础上,通过实际生产对比确定影响物料干燥条件的因素,并以此为据编写PLC程序,自动控制热、电能消耗。结果：以设备技改前后的热能和电能消耗对比为综合评价指标,节省蒸汽和电能消耗30％以上。结论：此类设备通过技术改进,提高了能源使用率,操作简便合理,重复性好,适合推广。     

基于SVM近红外光谱在烤烟烟叶产地判别中的应用研究

为研究近红外光谱分析技术结合支持向量机(SVM)模式识别原理在鉴别烟叶产地中的可行性,选择云南省曲靖市所辖6个不同区县的180个烟叶样品为研究对象。对其近红外光谱进行一阶求导后,通过matlab分析软件建立预测各烟叶产地的近红外模型,并应用该模型对78个烟叶样品进行实际产地预测。实验结果表明:上述方法建立的预测模型训练样本的正确识别率100.00%,测试样本正确识别率为91.03%。结果显示,运用基于SVM的近红外光谱技术可以实现烤烟烟叶产地的快速准确判定。     

水冷盘式制动器热疲劳失效有限元分析

针对海洋钻井绞车在连续下钻过程中的制动工况,建立了水冷盘式制动器三维热—机耦合分析模型,运用大型有限元分析软件ABAQUS数值模拟了制动器的制动过程,获得了制动盘表面及内部温度场与应力场的分布特征,并以此为基础分析了制动盘热疲劳失效的机理。研究结果表明:连续制动工况下,制动盘的温度场与应力场相互耦合,两者具有相似的变化规律;周向热应力是形成制动盘表面初始裂纹的主要应力分量,在热应力反复作用下,该初始裂纹发展为粗大的裂纹,最终导致制动盘的断裂。分析结果与实际情况吻合较好,从而证明了该分析方法的正确性和可行性。     

基于语义的新产品设计服务任务管理模型

针对新产品开发网络化设计服务的共性需求,提出了网上网下结合的设计服务模式、网络化设计服务公共平台体系结构和设计服务任务类型、特征属性及管理模型;采用OWL语言对设计服务任务进行形式化定义和描述,建立了基于语义的设计服务任务管理模型。通过网络化设计服务公共平台应用实例验证了设计服务任务管理模型的正确性和可行性。     

An improved stochastic subspace identification for operational modal analysis

An improved stochastic subspace identification algorithm is introduced to solve the low computational efficiency problem of the Data-driven stochastic subspace identification. Compared with the conventional algorithm, it needs much less cost of memory and computing time because it does not have a process of the QR decomposition of Hankel matrix. Model similarity index is proposed to measure the reliability of the modes obtained by the improved stochastic subspace identification. Furthermore, the stabilization diagram in combination with the modal similarity index is adopted to effectively indicate spurious modes resulting from noise and model redundancy. A criterion named the modal norm is introduced to indicate the dominating mode. A numerical example on the parameter estimation of a linear time-invariant system of 7 degrees of freedom and one experimental example on the parameter estimation of Chaotianmen bridge model in Chongqing are presented to demonstrate the efficacy of the method.     

过渡层焊丝对Monel 400复合钢板焊接性能的影响

采用 H1Cr2 6 Ni2 1作为过渡层焊丝 ,焊接 Monel40 0 / 16 Mn R复合板。研究了复合板焊接接头的弯曲性能、拉伸强度、主要化学元素在焊缝中的扩散程度及其微观组织。结果表明 ,焊缝成形良好 ,在距复层焊缝表面 2 .4mm范围内 ,焊丝化学成份对复层焊缝化学成份的稀释率为 0。焊接接头的拉伸强度为 6 30 MPa。面弯角大于等于 12 0°,背弯角为 180°,侧弯角大于等于 10 0°。焊接接头具有良好的综合机械性能。     

稀土变质消除铝合金压铸件中硬质点

初生硅和AlSiMnFe金属间化合物是造成铝合金压铸件中硬质点区域的主要因素,常规钠盐变质不能细化初生硅和Fe相,含有一定比例La,Ce,Pr,Nd和Yb的特殊配制的稀土合金不仅能细化共晶硅,而且细化初生硅并改善Fe相形貌,其中初生硅可细化到小于10μm,因此能有效消除铝合金压铸件中的硬质点区域。     

全自动棒材打捆机的研究

在对国外多种打捆机的研究基础上,本文提出了一种新型全自动棒材打捆机,其结构紧凑、易于操作和维护、基于PLC的双CPU模块控制系统,不但提高了打捆速度和可靠性,而且给予了良好的人机交互操作。并提出了打捆机并入现场总线的方法,利于实现钢铁厂的网络管理控制系统。     

Caustic imaging of gallium droplets using mirror electron microscopy

We discuss a new interpretation of mirror electron microscopy (MEM) images, whereby electric field distortions caused by surface topography and/or potential variations are sufficiently large to create caustics in the image contrast. Using a ray-based trajectory method, we consider how a family of rays overlaps to create caustics in the vicinity of the imaging plane of the magnetic objective lens. Such image caustics contain useful information on the surface topography and/or potential, and can be directly related to surface features. Specifically we show how a through-focus series of MEM images can be used to extract the contact angle of a Ga droplet on a GaAs (001) surface.     

Selective metallization of polymers using laser induced surface activation (LISA)��characterization and optimization of porous surface topography

Laser induced selective activation (LISA) is a molded interconnected devices technique for selective metallization of polymers. On the working piece, only the laser-machined area can be metalized in the subsequent plating. The principle of the technology is introduced. Surface analysis was performed on the laser-machined polymer using an Alicona InfiniteFocus? microscope. Based on previous experiments, bearing area curve and its parameters are chosen to characterize the surface. In this paper, by comparison of plateable and non-plateable surfaces, and two types of plateable surface made by different lasers, it is found that the normalized bearing area curve is an effective method to characterize porous surface for the subsequent plating. The normalized parameters are available to make a quantitative analysis.