总磷测定中标准曲线与工作曲线的比较

通过对钼锑抗分光光度法测定总磷的标准曲线和工作曲线的比较试验,并应用数理统计方法对结果加以分析,证明总磷测定中标准曲线与工作曲线无显著性差异(显著性水平为0.05,样本数为6),且两者具有相似的精密度和准确度。     

基于B样条曲线的充氮加塞包装机凸轮曲线设计

根据通常采用的凸轮曲线设计方法是根据从动件运动关系进行分段表述,不能从整体上对凸轮特性进行控制的情况,采用样条曲线函数表示从动件运动关系,并将其应用在充氮加塞包装机凸轮设计中。实现了充氮加塞包装机凸轮曲线的连续性设计,为其它包装机凸轮设计提供了参考。     

关于曲线检测的探讨

曲线测量一直是几何计量中的一个重点 ,本文阐述了已知曲线和未知曲线测量原理 ,利用 B样条拟合曲线 ,以及如何借助最小二乘对测量值 (二维 )进行最佳拟合和偏差处理     

迭函数系统(IFS)吸引子与几何曲线─—几何曲线的IFS-方程

迭函数系统是分形研究的重要方法之一。我们的研究证明,IFS也是绘制某些特殊几何图形的有效方法。本文则进一步指出,迭函数系统的吸引于是非常广泛的几何图形,可以是各种具有自相似特征的分形图案,奇怪吸引子,也可以是经典几何曲线。例如,圆和各种摆线。     

Curve adhesive joints

The behaviour of a curve adhesive joints between two generic profiles is investigated. In particular, a mechanical model accounting for the curvature radius is formulated as a generalization of a previous one introduced by the same authors in recent time.     

齿形误差曲线分析及其应用

笔者根据多年齿形检测中经常出现的一些误差曲线，根据它们的特点分别进行归类，并分析误差产生的原因，在实践中具有一定指导意义。     

非光滑曲线等长样条逼近

在工程计算中,常常需要对非光滑曲线进行光滑逼近.本文讨论了非光滑曲线在局部小区间上,可用保长度不变的光滑样条曲线来近似的问题.首先利用介值定理,从理论上证明:对定义在有限区间上的任意连续函数,只要曲线长度有限,则在该区间上可用光滑样条曲线来等长近似原曲线.在此基础上,通过选择恰当的插值节点,可以构造出一条唯一的光滑曲线,使其具有和原曲线形同的长度.同时,本文还给出具体构造光滑曲线的方法及详细计算过程.最后的数值结果表明这种方法既简单又行之有效,从而完整地解决了工程计算中曲线近似这一问题.     

三次Ball曲线的扩展

给出了一个含有参数λ的四次多项式基函数,它是三次Ball曲线基础函数的扩展.分析了此基函数的性质,基于该组基函数定义了带有形状参数的多项式曲线.曲线不仅具有三次Ball曲线的特性,而且具有形状的可调性和更好的逼近性.参数λ有明确的几何意义:λ越大,曲线越逼近控制多边形;当λ=0时,曲线退化为三次Ball曲线.还讨论了两段曲线C1连续拼接的条件.实例表明,曲线形状随λ的取值不同而发生变化.     

四次Wang-Ball曲线的扩展

给出了一个含有参数λ的五次多项式基函数,是四次Wang-Ball 曲线基函数的扩展.分析了此基函数的性质,基于该组基函数定义了带有形状参数的多项式曲线.曲线具有四次Wang-Ball 曲线的特性,改变参数λ的值,可以调整曲线的形状.当λ=0时,曲线退化为四次Wang-Ball曲线.还讨论了两段曲线C1连续拼接的条件.实例表明,该方法应用于曲线设计是十分有用的.     

介电型电磁波吸收体元反射曲线的扩展与重建

介电型电磁波吸收体的无反射曲线一直是设计高性能吸波材料的重要依据.但传统的无反射曲线仅仅可用于单层材料,无法实现谐振型电磁波吸收体的设计.通过对λ/4型电磁波吸收体理论研究发现:λ/4型电磁波吸收体也可建立起无反射曲线.其特性与表面电阻等参数相关,且更为普适,是传统无反射曲线的扩展,而传统的无反射曲线演化为只是它的一个...     

Nonparametric Dynamic Curve Monitoring

Rapid sequential comparison between the longitudinal pattern of a given subject and a target pattern has become increasingly important in modern scientific research for detecting abnormal activities in many data-rich applications. This article focuses on this problem when observations are collected sequentially with uncorrelated or correlated noise involved. A dynamic monitoring procedure is developed after connecting the curve monitoring problem to curve comparison. Under the framework of generalized likelihood ratio testing, we suggest a new exponentially weighted moving average (EWMA) control chart that can accommodate unequally spaced design points. An adaptive parameter selection feature is built in the proposed control chart so that the chart can detect a wide range of longitudinal pattern shifts effectively. To furnish fast computation, recursive formulas are derived for computing the charting statistic. Numerical studies show that the proposed method can deliver a satisfactory performance, and it outperforms existing methods in various cases. An example from the semiconductor manufacturing industry is used for the illustration of its implementation. Supplementary materials for this article are available online.     

Self Modeling Curve Resolution

This paper presents a method for determining the shapes of two overlapping functions f ₁(x) and f ₂(x) from an observed set of additive mixtures, [α _i f ₁(x) + β _i f ₂(x); i = 1, …, n), of the two functions. This type of problem arises in the fields of spectrophotometry, chromatography, kinetic model building, and many others. The methods described by this paper are based on the use of principal component techniques, and produce two bands of functions, each of which contains one of the unknown, underlying functions. Under certain mild restrictions on the f_j (x), each band reduces to a single curve, and the f_i (x) are completely determined by the analysis.     

一种生成卵形曲线的方法

利用几何变换的方法解决了卵形曲线的生成问题。以椭圆作为变换的初始曲线,按照所给条件对其使行变换。讨论了该曲线的形成过程,创建了相应的数学方程。分析了方程中各参数的意义及所表达的曲线的特性,并根据所建的数学方程进行编程、验证,结果表明,所绘出的图形与分析完全吻合。     

Magnetization Curve of the Kagome-Strip-Lattice Antiferromagnet

We study the magnetization curve of the Heisenberg model on the quasi-one-dimensional Kagome-strip lattice that shares the same lattice structure in the inner part with the two-dimensional Kagome lattice. Our numerical calculations based on the density matrix renormalization group method reveal that the system shows several magnetization plateaus between zero magnetization and the saturated one; we find the presence of the magnetic plateaus with the n/7 height of the saturation for n=1,2,3,4,5 and 6 in the S=1/2 case, whereas we detect only the magnetic plateaus of n=1,3,5 and 6 in the S=1 case. In the cases of n=2,4 and 6 for the S=1/2 system, the Oshikawa-Yamanaka-Affleck condition suggests the occurrence of the translational symmetry breaking (TSB). We numerically confirm this non-trivial TSB in our results of local magnetizations. We have also found that the macroscopic jump appears near the saturation field irrespective of the spin amplitude as well as the two-dimensional Kagome model.     

仪器化落锤冲击试验曲线分析

仪器化冲击试验机的发展使冲击试验过程可视化、定量化、数字化。通过对数千次冲击试验的曲线及数据分析，体会到除总冲击功外，还有屈服力、最大力、稳定裂纹扩展的出现、不稳定裂纹扩展起始力及终止力、试样弯曲位移、冲击过程的时间等大量数据，可供人们更准确、定量地进行金属材料力学性能的比较分析与评价。对金属材料制造技术的研究开发和最佳轧制工艺的确定，具有重要价值。     

家具设计的曲线之美

分析了曲线美的缘由、特点及在家具设计中的表现方式,通过对经典设计的解读,论述了家具设计中曲线造型与材质、结构、现代的加工技术相结合形式美的表现,阐述曲线在家具人机工学、空间使用层面的功能美体现,进而分析了家具设计中曲线简约而含蓄的形态,多相但亲柔的情境表达。在此基础上,提出了曲线家具既能和知觉主体一起营造物象形态,又可以使审美主体的内在情感得以直接抒发的特质和应用途径,希望有助于指导设计实践。