三维编织复合材料编织工艺过程仿真研究

总结了四步编织工艺的运动规律。对纱线的空间坐标进行三次B样条曲线拟合得到拟合坐标;设计实现了纱线实体的静态模型算法,根据拟合坐标得到纱线空间网格坐标并建立了纱线实体的静态模型;实现了纱线轨迹的动态展示以及实体生成过程的动态展示;构建了GUI界面并编译成了可脱离Matlab环境的独立运行程序。     

基于HLA的分布式仿真框架自动生成技术

针对基于HLA仿真应用系统开发中存在的计算模型程序与RTI服务程序的耦合问题,研究了基于共享内存和中断回调技术的解耦方法,进一步采用HLA仿真适配器对RTI服务程序进行封装,从而实现了计算模型程序与RTI底层服务程序的有效隔离。为提高仿真应用程序开发效率,分析了联邦成员中RTI服务程序功能需求,研究实现了仿真适配器自动生成软件。该软件可快速生成基于HLA的联邦成员适配器代码和执行程序,从而构建仿真应用系统分布式仿真框架。     

基于ASL的模型驱动架构测试方法

针对模型驱动架构（MDA）下的软件开发方法中测试启动比较晚、难以发现隐藏在模型中的缺陷及UML模型描述缺乏精确语义等问题,提出了基于ASL的模型测试方法：从UML模型出发,将动作规约语言（ASL）运用于平台无关模型（PIM）上建立测试模型。给出了ASL语句在MDA过程中的工作原理、平台无关模型的建立过程、测试用例建立的步骤、测试执行的实施过程,最后结合实例,在UML图的基础上运用ASL对测试环境进行构建,并创建了系统的测试用例,对模型及业务逻辑进行了测试。实验结果表明,提出的基于ASL的模型测试方法既能利用模型驱动对复杂的测试用例进行简化和抽象,又能在软件生存期早期揭示软件的缺陷,防止缺陷随着软件开发过程的进行而被放大。     

基于认知负荷理论的多媒体课件设计研究

多媒体课件的信息加工主要包括信息的选择、组织和整合策略,它直接影响学习者对学习内容的选择、组织和整合。目前高校的多媒体课件比较注重体现多媒体技术形象直观、信息量大、效率高等特点,却往往忽视过量信息加工和学习者认知资源有限之间的矛盾。依据认知负荷理论,合理设计多媒体课件中文字、图片、声音、动画和视频等的呈现方式,可以降低认知负荷,最大限度提高学习者的信息加工水平,以达到提高教学效果的目的,同时对指导当前多媒体辅助教学实践也有重大意义。     

基于改进型批决策与调度建模的生产计划调度系统的研究

热轧型钢生产工艺复杂,其生产中极易出现由于计划调度安排不当而产生的交货期延误、库存超负荷等问题。针对以上问题研究设计了MES生产计划调度系统,改进了批决策调度策略用于数学建模,利用自适应遗传算法求解生产调度计划。以此为基础,为某热轧企业设计实现了生产计划调度系统,并通过真实的热轧型钢订单、原料、设备等数据,对模型改进前后的计划编制方法进行模拟与比较,验证了利用该改进型批决策与调度模型编制的热轧型钢生产调度计划可节省生产时间、降低设备调度时间,以此来指导热轧型钢的生产可切实减少交货延误和减少库存占用率,并提高企业利润率。     

基于UG的密炼机转子三维设计

综合分析密炼机转子三维设计的常用方法，利用UG软件扫描成型和复合建模方法、尺寸相关和表达式工具对密炼机转子进行三维设计，并利用电子表格建立了转子图库。应用该方法设计的转子三维模型可用于计算和分析，并为后续加工处理提供便利。     

Preparation and characterization of carboxymethyl konjac glucomannan/sodium montmorillonite hybrid films

Carboxymethyl konjac glucomannan (CKGM)/ sodium montmorillonite (MMT) hybrid films of various compositions were prepared by casting from a polymer/silicate water suspension. The structure and properties of the hybrid films were investigated by wide angle X‐ray diffraction (WAXD), transmission electron microscopy (TEM), attenuated total reflection infrared spectroscopy (ATR‐IR), differential scanning calorimetry (DSC), and tensile tests. The results from WXRD and TEM indicated that an intercalated CKGM/MMT nanocomposite film was obtained by polymer solution intercalation. WXRD and DSC showed that the high‐T_m crystal phase was induced by the presence of lower MMT loading, but the T_m of the hybrid films became weak with the increase of MMT content due to the polymer confinement. The hybrid films showed higher thermal stability and mechanical properties than that of the neat polysaccharide due to the strong interaction between hydroxyl and carbonyl group of CKGM and the silicate layer of MMT. Furthermore, the degree of swelling of the hybrid films was investigated in acidic buffer solutions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2954–2961, 2007     

Self-assembled patterned CoFe2O4-SrRuO3 electrodes: Enhanced functional properties by polar nano-regions reorientation

Epitaxial CoFe₂O₄ (CFO) and SrRuO₃ (SRO) nanopillar heterostructures were deposited on Pb(Mg_1/3Nb_2/3)_0.70Ti_0.30O₃ (PMN-30PT) single crystal substrates by switch pulsed laser deposition (SPLD). Since the CFO nanopillars are insulating, and the SRO matrix conductive, this self-assembled nanopillar heterostructure served as a patterned electrode on PMN-PT, which then enhances the dielectric and piezoelectric constant of the substrate. Cross-sectional electron microscopy images revealed the formation of a nanopillar heterostructure layer with CFO nanopillars within a SRO matrix. AFM and XRD revealed good topography and epitaxy, indicating a high quality SRO-CFO self-assembled nanopillar structure. Using a SRO-CFO thin film patterned electrode, PMN-PT was found to have a notably higher (30%) dielectric constant with increasing electric field and enhanced transverse broadening in reciprocal spacing mapping (RSM) scans.     

CORRELATION OF DIFFUSION COEFFICIENTS FOR LIQUIDS AND DENSE FLUIDS WITH TEMPERATURE AND PRESSURE

On the basis of the free volume theory and activation energy concept,a fundamental equation whichtakes into account the effects of temperature and pressure has been developed.By introducing differentexpressions for the free volume and activation energy,several equations for fluid diffusion coefficients were derivedaccordingly.With the van der Waals free volume and intermal energy formula,a three-parameter model for fluiddiffusion coeffficients at moderate pressure was obtained.The grand average absolute deviation percent of 345data points (44 systems)for self-and infinite dilute inter-diffusivities is 2.32,against the results of the model ofCohen and Turnbull,4.13.In particular,by means of the modified Carnahan-Starling free volume equation,afour-parameter model with average abosolute deviation percent 2.64(30 systems,644 data points)for theestimation of dense fluid inter-and self-diffusivities at high pressures and in supercritical conditions was derived.The derived model is superior to the method of L     

改进BP神经网络在木构古建筑中的寿命预测

标准的BP神经网络存在训练速度慢、容易陷入极小点、泛化能力低的特点。文中用附加动量项和改进学习速率相结合的方法对标准的BP神经网络进行了改进,并将其应用在木构古建筑的寿命预测中。仿真结果表明,和标准的BP神经网络相比,改进后的BP神经网络提高了泛化能力,能较准确地拟合训练值,避免了在确定计算参数过程中所产生的计算误差。