评价机械加工表面形貌的小波变换方法

提出了用小波变换计算粗糙表面分形维数的新方法 ,并基于Weierstrass -Mandelbrot函数 (W -M函数Majumdar-Bhushan函数 (M -B函数 )对该方法进行了验证 ,结果表明该方法具有很高的计算精度。应用小波变换方法对核态池沸腾试验板表面形貌的分形特征进行了评价 ,包括铜和不锈钢材料 ,轧制、砂纸打磨和表面机械抛光等 3种加工方法生成 5个粗糙度级别的试验板 ,研究结果表明该方法能有效评价表面形貌的分形特征。     

STUDY ON IMAGE EDGE PROPERTY LOCATION BASED ON FRACTAL THEORY

0 lNTRODUCTlONWith the rapid development of assembleautomatic,machine visinn has been poPularly used onsudsce mounted technofogy (SMT ) field. It hasreSOved many problems in electronic factory assemblyline environments. Ref. [ l ] -- Ref. [ 41 gave someexamples, which resolved many insPeCtion prOblems inSMT from the views of image process and imageaedysis, image defect clinic strategy and somecommerce vision system. Teday, the machine visionbranch system is used in almost all of the h…     

多股射流瓦斯燃烧器湍流扩散火焰尺度的实验研究

用火焰图像分析方法,对一种多股射流燃烧器燃烧富含氢气的瓦斯产生的湍流扩散火焰的尺度进行了实验研究,研究了燃烧器结构参数和操作参数对火焰长度和长宽比等尺度特性的影响规律。结果表明,火焰长度随燃烧器喷孔总面积的增大和燃气流量的增大而增大,随助燃空气过剩系数的增大而减小;火焰长度和长宽比随上层喷孔位置角的增大而减小。同时发现,瓦斯中氢气含量对火焰尺度影响较大,随着氢气含量增大,火焰长度和长宽比都明显减小。     

神经元网络奇怪吸引子的计算机模拟

为模拟神经元网络的混沌现象,阐述了相空间重构技术,介绍了由一维可观察量计算系统的最大Lyapunov指数和关联维数的方法。利用Lyapunov指数作判据,构造了3层反馈神经元网络的奇怪吸引子,分析了奇怪吸引子的运动特征并计算了奇怪吸引子的关联维数。研究表明混沌神经元网络具有复杂的动力学特征,同时存在各种吸引子,不仅有不动点、极限环、环面,而且有奇怪吸引子。     

新疆某铜矿区化探数据异常下限确定方法对比研究

本文以新疆某1 ∶50 000化探数据为例,运用累频法、均值标准差法、以及面积—周长(C-A)分形方法计算研究区主要成矿元素Cu异常下限值,并运用不同的异常下限值圈定了铜的地球化学异常,并对不同方法进行了对比分析,实践表明,分形法确定的异常下限更适合于本研究区.     

断面的分形研究

应用分形法对断面破坏机理进行定量分析,并根据原子力显微镜的测量结果分析断面。研究分析表明:分维数可以作为定量分析的一个参数,也可以定量地评价破损的复杂性。     

注塑件特征建模及塑件智能尺寸换算

探采用基于特性和知识相结合的技术，建立注塑件产品模型，实现注塑件尺寸到成形零部件尺寸的智能转换，为建立注塑模型腔型芯模型打下基础，并以ＵＧＩＩＶ９．０为支撑软件，用其Ｍａｃｒｏ及二次开发语言Ｇｒｉｐ实现。     

Flutter of high-dimension nonlinear system for a FGM truncated conical shell

The nonlinear flutters of a truncated conical shell, which is subjected to aerodynamic pressure and aerodynamic heating, are researched. Material properties with gradient features along the radial direction depend on the temperature. The supersonic aerodynamic force is obtained by applying the first-order piston theory, including the correction factor for curvature. The temperature in the external surface of the functionally graded material truncated conical shell rises as a result of viscous aerodynamic heating, and the temperature distribution along the thickness can be described by polynomial series. Hamilton's principle is utilized to obtain the nonlinear partial differential equilibrium equation of the system. Using Galerkin's method, a high-dimensional nonlinear system can be derived. Without considering the parts of nonlinear terms and the external forcing excitation, the flutter boundaries are obtained by solving the eigenvalues problem. The influences of ratios of top radius to thickness, semi-vertex angle, and volume fraction index on nonlinear dynamic characteristics of functionally graded material truncated conical shell are studied in detail by the fourth-order Runge–Kutta algorithm.     

Characterization of fractured basement reservoir using statistical and fractal methods

This study presents a characterization of fractured basement reservoir by using statistical and fractal methods with outcrop data, seismic data, as well as FMI log data. In the statistical method, fracture intensity and length have been calculated from various outcrop data. The optimum statistical distribution functions of fracture length for outcrops have been identified with the use of discriminant equation derived from Crofton’s theory. The Fisher distribution constant, representing the fracture orientation, has been computed from FMI log data. With the statistical values and distribution functions, a 3D fracture network system has been generated. The result shows that there is no distinction in orientation of the fracture network system, and it excellently matches with the outcrop data. In the fractal method, fractal dimensions of fracture length and strike for the seismic fracture network in areal distribution were calculated; a greater value in fractal dimension means that the fracture network system has intensive fractal characteristics. Meanwhile, vertical distribution and dip angle of the fracture system have been evaluated from FMI log data. The resulting 3D fracture system presents that the overall strike and distribution of the fracture system are excellently matched with those of seismic data.     

基于多维度映射的类圆簇识别算法

为了深入地探索聚类结果簇的形态特征,提出了一种基于维度映射的类圆簇识别算法。该算法将结果簇按维度进行映射,通过比较、分析簇在各个映射维度上的频数曲线及形态特征,自动将类圆簇从众多结构复杂的聚类结果簇中识别出来。算法经过大量实验验证,具有很好的识别能力和抗干扰能力,对于高维度数据集合也具有很强的扩展性。