Multi-Focus Image Fusion Using Curvelet Transform

Curvelet transform is a new muiti-scale geometic analysis, which has the characteristics of anisotropy. It is more suitable for the analysis of image curve edge characteristics than wavelet. Thus, in this paper it is applied to multi-focus image fusion, and used fusion rules that suitable for the characteristics of multi-focus image fusion.

Effect of Geometry on Stress Distribution of Spew Fillet of Co-Cured Composite Single Lap Joint

Spew fillet is common in co-cured composite single lap joint. It plays an important role in the safety of the joint. In this paper, three spew fillets with typical geometries under static tensile load were investigated numerically using the commercial finite element code ANSYS. The computation results indicated: the fillet with a long curve edge had better performance than other fillets.

The Optimization of Edge-Shape Parameter for Curve-Edge Milling Insert Based on Thermal-Mechanic Coupling Physical Field

The edge shape of milling insert has important influence on the heat loading and mechanical loading during metal cutting. The optimization of edge-shape parameter for curve-edge milling insert based on evaluation criteria of thermal-mechanic coupling field was carried out in order to improve the thermal-mechanic coupling field and to raise lifetime and production rate of milling insert. A new edge shape function was obtained. The curve-edge milling insert was designed driven by the edge function. The coupling field of milling insert has obvious improvement by finite element analysis (FEM). The maximal equivalent stress and displacement in cutting deformation area decreased by 17.2% and 15.7% respectively.

A Numerical Method for Preserving Curve Edges in Nonlinear Anisotropic Smoothing

We focus on nonlinearity for images and propose a new method which can preserve curve edges in image smoothing using nonlinear anisotropic diffusion (NAD). Unlike existing methods which diffuse only among the spatial variants, the new method suggests that the diffusion should be performed both among the time variants and spatial variants, named time and space nonlinear anisotropic diffusion (TSNAD). That is, not only the differences of the spatial variants should be estimated by the nearby spatial points but also the differences of the time variants should be approximated by the weighted time differences of nearby points, according to the differences of gray levels between them and the consideration point. Since the time differences of nearby points using NAD can find more points with similar gray levels which form a curve belt for the center pixel on a curve edge, TSNAD can provide satisfied smoothing results while preserving curve edges. The experiments for digital images also show us the ability of TSNAD to preserve curve edges.

Study on Grinding Technology of Electrical Discharge Grinding of Curve Edge Polycrystalline Diamond

PCD tools, especially curve edge PCD compound tools are used widely in machining nonferrous and non-metal materials with high efficiency and precision because of their excellent cutting properties. But high quality grinding of PCD tools is the uppermost obstacle in application because there are great difficulties to profile and sharpen edge in grinding, especially for milling cutter and drill with curve edge. This paper studied technology of wire EDG curve edge PCD compound tools by wire electrical discharge grinding machine with five-axis CNC system. The grinding quality was evaluated by scanning electron microscope (SEM) and roughometer. Three steps processing technique (roughing, finishing and fine finishing) and optimal process parameters of wire EDG PCD tools were recommended after considering synthetically the surface quality, precision and machining efficiency. The results met the requirement of high surface quality, precision and efficiency. This paper also applied successfully the optimal technology to grind a PCD milling cutter with outer and inner blade by electrical discharge grinding machine with five-axis CNC system. By the optimal parameters, the process yielded high precision of ±4.3µm and low roughness of 0.30µm. Experiment results have great practical significance to the high precise and efficient wire EDG of PCD tools.