带孔拉延各种变形趋向的定量计算

本文对带孔拉延的各种变形趋向进行了分析,给出了对应的工艺方案及定量计算公式。针对生产中可能出现的不同润滑状态,设计了软件运行框图。运行及试验研究证明,该方案及公式可以估算生产和设计中出现的各种尺寸带孔拉延问题并适用于所有冲压材料。     

从《资本论》体系到新文学理论体系的构建——关于构建文学理论体系的再思考

受马克思《资本论》体系的启示 ,反思以前提出的新文学理论体系 ,一个更加新颖的文学理论体系构建出来了。这个体系以“对文学作品的分析”为逻辑起点 ,由“文学的作品”、“文学的创作”、“文学的接受与发展”这三大相互连接的板块构成。这三大板块又含有层层递进的 1 2个层次 :文学作品的构成→文学意象→文学形象→文学的意境、典型→文学的构成途径→文学创作的方法论→文学的创作→文学作品的形态与分类→对文学的需要→文学的接受→文学的发展→文学的反馈     

A penalized likelihood approach to image warping

A warping is a function that deforms images by mapping between image domains. The choice of function is formulated statistically as maximum penalized likelihood, where the likelihood measures the similarity between images after warping and the penalty is a measure of distortion of a warping. The paper addresses two issues simultaneously, of how to choose the warping function and how to assess the alignment. A new, Fourier–von Mises image model is identified, with phase differences between Fourier-transformed images having von Mises distributions. Also, new, null set distortion criteria are proposed, with each criterion uniquely minimized by a particular set of polynomial functions. A conjugate gradient algorithm is used to estimate the warping function, which is numerically approximated by a piecewise bilinear function. The method is motivated by, and used to solve, three applied problems: to register a remotely sensed image with a map, to align microscope images obtained by using different optics and to discriminate between species of fish from photographic images.     

紫外光固化固结磨料研磨盘研磨铜片的研究

采用UV固化工艺,将粒径为15 μm左右的白刚玉（氧化铝）磨料固结于光固化树脂中,通过添加NaCl来制造气孔,制备固结磨料研磨盘(FALP) 。选取工件的材料去除率(MRR)和表而粗糙度Ra来评价研磨的加工性能。对比研究了在相同粒径磨粒下的游离磨料研磨、不同气孔率的固结磨料研磨多种方法对铜片的加工性能。[HTK]实验结果表明：固结磨料研磨铜片的去除速率是游离磨料加工的5~7倍,而经前者研磨的铜片表面粗糙度Ra值为0.083 μm,大于后者的0039 μm。含添加物的固结磨料研磨盘所加工的铜片的表面粗糙度Ra值较未添加的相对较好。     

基于联合变换的旋转不变光学图像加密

利用两个彼此独立的编码脉冲相位掩模在联合变换相关器中对需要保护的图像进行编码,实现对原始图像的加密。该方法的特点是解密时加密图像的旋转不会影响解密效果,相位分布是密钥的合法持有者唯一掌握的确定性函数,可以重构,便于实际应用。计算机模拟的结果证明了方法的可行性。     

圆缺孔板在油气双相流量测量中的应用

本文介绍了利用圆缺孔板和罗兹流量计组合进行油气双相流量测量的研究。在被测介质干度x=0.001～0.752范围内,采用分相动量模型和修正能量模型进行数据整理。试验结果表明,在上述范围内,各项数据的均方根误差均小于10%,且采用动量模型整理数据的结果要优于修正能量模型。     

40m上承式钢板梁桥加固前后动力特性研究

从理论上对钢板梁桥横向加固效果进行了定性分析，并应用大型有限元分析软件AN-SYS建立了加固前后桥梁结构的三维空间有限元模型。通过模态分析获得了加固前后结构前10阶自振频率和振型，并对几种方案的加固效果进行了定量分析，得出有意义的结论。     

Spline smoothing over difficult regions

Summary. It is occasionally necessary to smooth data over domains in R ² with complex irregular boundaries or interior holes. Traditional methods of smoothing which rely on the Euclidean metric or which measure smoothness over the entire real plane may then be inappropriate. This paper introduces a bivariate spline smoothing function defined as the minimizer of a penalized sum-of-squares functional. The roughness penalty is based on a partial differential operator and is integrated only over the problem domain by using finite element analysis. The method is motivated by and applied to two sample smoothing problems and is compared with the thin plate spline.     

Thin plate regression splines

Summary. I discuss the production of low rank smoothers for d  ≥ 1 dimensional data, which can be fitted by regression or penalized regression methods. The smoothers are constructed by a simple transformation and truncation of the basis that arises from the solution of the thin plate spline smoothing problem and are optimal in the sense that the truncation is designed to result in the minimum possible perturbation of the thin plate spline smoothing problem given the dimension of the basis used to construct the smoother. By making use of Lanczos iteration the basis change and truncation are computationally efficient. The smoothers allow the use of approximate thin plate spline models with large data sets, avoid the problems that are associated with 'knot placement' that usually complicate modelling with regression splines or penalized regression splines, provide a sensible way of modelling interaction terms in generalized additive models, provide low rank approximations to generalized smoothing spline models, appropriate for use with large data sets, provide a means for incorporating smooth functions of more than one variable into non-linear models and improve the computational efficiency of penalized likelihood models incorporating thin plate splines. Given that the approach produces spline-like models with a sparse basis, it also provides a natural way of incorporating unpenalized spline-like terms in linear and generalized linear models, and these can be treated just like any other model terms from the point of view of model selection, inference and diagnostics.     

一种基于现场总线和PLC的中厚板轧机伺服控制系统应用分析

随着社会经济的发展,以及计算机和PLC控制技术的发展,中厚板生产企业面临着激烈的市场竞争。因此,对于中厚板生产企业来说,要想使利润达到最大化,就必须实现低成本、高质量以及高成材率的指标。首先了解PLC在中厚板轧机中实现自动化控制的要点,针对西门子PLC、Profibus DP现场总线技术组成中厚板轧机的伺服控制系统,从控制系统的硬件设计、系统软件的设计、系统工艺的控制功能以及系统优化所实现的功能进行探讨和优势分析。