基于动态相变的细晶双相低碳钢组织控制

利用Gleeble1500热模拟单向压缩实验机，通过观察不同原奥氏体晶粒的过冷奥氏体在动态相变过程中的组织演变，分析了动态相变过程中马氏体岛形貌以及分布的演变特征，并考察了原奥氏体晶粒大小、形变温度和形变速率等参数对组织转变动力学的影响，探讨了基于动态相变的细晶双相低碳钢的组织控制规律、结果表明，通过调整原始奥氏体晶粒尺寸并控制过冷奥氏体动态相变进程，可以获得在均匀细小的铁素体（2～3μm）基体上弥散分布着不同体积分数、颗粒状细小马氏体岛的双相钢。     

一种基于海量船舶轨迹数据的细粒度网格海上交通密度计算方法

在"一路一带"的战略构想下,对于海上贸易的关注逐渐升温。海上运输是海上贸易的承载,掌握细粒度的海上交通密度,对于提取热点航道热点区域、分析全球贸易走势、推断海上交通连通性及相关的异常检测等具备重要的意义。提出了一种面向海量船舶轨迹数据的细粒度网格海上交通密度计算方法,该方法将全球划分为0.01°*0.01°的标准化细粒度网格,一方面为了适应细粒度网格对全球船舶真实轨迹数据特点设计了针对性的预处理方案,处理了异常点和停泊点;另外一方面设计并实现了一种面向该网格的利用海量轨迹数据对信息发送数目、信息发送间隔、经过船舶数目、经过船舶时间等多维交通密度特征进行量化计算的方法,具备良好的拓展性。最后采用2014年2个月共计8亿余条数据对该方法的性能、准确性进行了评估验证,证明了该方法的切实可行性。     

无黏性混合土临界细粒含量的多途径判别研究

临界细粒含量反映了无黏性混合土颗粒级配和结构性对力学性状的重要影响,其值的确定是一个相互验证的过程。假设无黏性混合土具有砂-粉二元结构,在此基础上通过理论分析颗粒骨架于孔隙比的影响,运用土体基本物理指标对临界细粒含量的范围进行了预测;最大孔隙比和最小孔隙比随着细粒含量的变化反映了颗粒的形状和相互间接触关系,由此得到的临界细粒含量也是区间值;分形理论中的分维数反映了土体颗粒结构的自相似性,通过分形维数变化情况的探讨进一步缩小了临界细粒含量的取值;稳态线反映出无黏性混合土的力学性质特征,取稳态线斜率变化处的细粒含量为临界细粒含量。后两种方法得到的临界细粒含量均在前两种方法获得的区间范围内。综合各种方法,得出由南京砂重塑得到的无黏性混合土的临界细粒含量为25%。     

基于多功能数据采集卡和变速PID的转台控制系统设计

为了提高采用转台对惯性导航系统和惯性仪表进行误差模型标定时的可靠性和精度,对角位置转台的控制系统进行了研究;首先借助NI公司PXI-8101控制器和功能强大的数据采集卡PXIe-6363对转台控制系统进行了硬件设计;随后在对转台常规PID控制方法研究的基础上提出了一种能随系统调节偏差自动改变积分项累加速度的变速PID控制方法;接着又对基于软件实现的双通道旋转变压器轴角解调算法进行了研究并提出了一种粗精组合角纠错方法;最后文章设计的转台控制系统进行了测试实验,结果表明提出的轴角解调算法具有较好的解码速度和精度,并且变速PID控制方法大大提高了转台控制系统的自学习能力和鲁棒性,显著地改善了转台控制过程的稳定性.     

一种改进编码器角度解算过程的方法与实现

在机械电子一直是一个热门学科,其目的是通过软件控制机械操作来代替机械的哑巴解决方案。DS-25旋转电子编码器能够很好地与机械电子应用相匹配,其输出为两路标准的sine和cosine曲线,通过分析sine和cosine数值来计算编码器所对应的绝对角度位置。通过对DS-25的工作模式分析和实际应用情况提出角度解算的改进方案,该方案利用DS-25工作于粗略模式下测试到的角度值来推算精确模式下的信号周期,结合精确模式下测试到的角度值来计算编码器所对应的绝对角度。摒弃其原有的复杂查表过程进而节省电子表格的存储空间,在降低硬件成本的同时提升了软件灵活性。实验证明,算法的改进能够节省约2KB的存储空间,角度位置误差能控制在1‰以内。     

基于小波变换的图像配准

图像配准是信息融合处理中的重要环节。本文分析了图像配准的数学模型,并对小波变换进行了研究。基于小波理论,提出了一种高精度的图像配准方法。该方法利用小波变换将图像分成若干层次,按照互信息最大的原则对小波分解各层的近似分量求取其配准参数,最后通过迭代实现图像配准。实验结果表明,该方法配准精度高、可靠性好,较之传统的方法有明显的优越性。     

论中国传统女红文化资源的传承和发展

本文从阐述传统女红文化的内涵入手,对女红文化资源面临的危机与表现进行了深入的分析;通过对中国传统女红文化的发展前景进行理论剖析,指出了保护、传承中国传统女红文化资源的必要性,并对传统女红文化的继承和发展提出合理化建议,使中国传统女红文化资源在现代社会得到传承和发展。     

绘画的性格

风格多样的绘画艺术作品向我们展示了其丰富的性格魅力,绘画性格的表象特征揭示和体现着时代的气息与艺术家自身的性格与内涵的构成。其具有不可复制性与唯一性。我们只有以真诚的心去对待画面和艺术,不断提高自身的理论素养,细心体味生活,才能更深入、更贴近艺术的真实和内心自我的真实。     

New insights into the morphology of Trypanosoma cruzi reservosome

Reservosomes are late endosomes present only in members of the Schizotrypanum subgenus of the Trypanosoma genus and are defined as the site of storage of endocytosed macromolecules and lysosomal enzymes. They have been extensively described in Trypanosoma cruzi epimastigote: are bounded by a membrane unit, present an electron-dense protein matrix with electron-lucent lipid inclusions, being devoid of inner membranes. Here we performed a detailed ultrastructural analysis of these organelles using a variety of electron microscopy techniques, including ultrathin sectioning, uranyl acetate stained preparations, and freeze fracture, either in intact epimastigotes or in isolated reservosomes. New informations were obtained. First, both isolated and in situ reservosomes presented small profiles of inner membranes that are morphologically similar to the membrane surrounding the organelle. In uranyl acetate stained preparations, internal membrane profiles turned out to be longer than they appeared in ultrathin section images and traversed the organelle diameter. Internal vesicles were also found. Second, endocytosed cargo are not associated with internal vesicles and reach reservosomes on board of vesicles that fuse with the boundary membrane, delivering cargo directly into reservosome lumen. Third, electron-lucent bodies with saturated lipid core surrounded by a membrane monolayer and with unusual rectangular shape were also observed. Fourth, it was possible to demonstrate the presence of intramembranous particles on the E face of both internal vesicles and the surrounding membrane. Collectively, these results indicate that reservosomes have a complex internal structure, which may correlate with their multiple functions.     

Aniline hydrogenolysis on nickel: effects of surface hydrogen and surface structure

Fluorescence yield near-edge spectroscopy (FYNES) above the carbon K edge and temperature programmed reaction spectroscopy (TPRS) have been used as the methods for characterizing the reactivity and structure of adsorbed aniline and aniline derived species on the Ni(100) and Ni(111) surfaces over an extended range of temperatures and hydrogen pressures. The Ni(100) surface shows appreciably higher hydrogenolysis activity towards adsorbed aniline than the Ni(111) surface. Hydrogenolysis of aniline on the Ni(100) surface results in benzene formation at 470 K, both in reactive hydrogen atmospheres and in vacuum. External hydrogen significantly enhances the hydrogenolysis activity for aniline on the Ni(100) surface. Based on spectroscopic evidence, we believe that the dominant aniline hydrogenolysis reaction is preceded by partial hydrogenation of the aromatic ring of aniline in the presence of 0.001 Torr of external hydrogen on the (100) surface. In contrast, very little adsorbed aniline undergoes hydrogen induced C-N bond activation on the Ni(111) surface for hydrogen pressures as high as 10^–7 Torr below 500 K. Thermal dehydrogenation of aniline dominates with increasing temperature on the Ni(111) surface, resulting in the formation of a previously observed polymeric layer which is stable up to 820 K. Aniline is adsorbed at a smaller angle relative to the Ni(111) surface than the Ni(100) surface at temperatures below the hydrogenolysis temperature. We believe that the proximity and strong -interaction between the aromatic ring of the aniline and the surface is one major factor which controls the competition between dehydrogenation and hydrogen addition. In this case the result is a substantial enhancement of aniline dehydrogenation relative to hydrogenation on the Ni(111) surface.