Advanced Materials Research Vol. 459

Abstract: The experiments of micro-hole ablation are conducted firstly on titanium alloy Ti-6Al-4V with Nd: YAG millisecond laser. A significant factor which affects the depth of blind hole is found: the depth of recast material. This paper closely examines the regularity of recast depth varying with laser parameters, discovering that the ratio of recast depth to the entire hole depth decreases as pulse width decreases, and increases as peak power decreases. Verification experiment is conducted on stainless steel 1Cr13, eventually micro-hole with very thin recast layer is drilled when the maximum peak power and the minimum pulse width of the present millisecond laser are used.

Abstract: According to a ray casting algorithm，a method of 3-D image reconstruction in optical coherence tomography systems is presented. Volume data formed by a series of cross-sectional 2-D images are obtained experimentally in a traditional OCT system and a full-field OCT system. Using the ray casting algorithm, 3-D images have been reconstructed from these data base on VTK. The 3-D images rendering apparently reflect the corresponding details of samples

Abstract: In this paper, ANSYS, a finite element analysis software is used to simulate the change of temperature field in micro-hole processing with millisecond laser, which determines the diameter and depth of the hole drilled. The relationship between processing parameters and the hole size is plotted, so as to achieve size control of a micro-hole processing. Compared with experimental results, simulation is effective for laser processing of micro-hole and can be referenced to choose the best processing parameters.

Abstract: In this paper, the development and basic theory of co-rotational finite element method is introduced. The framework of constructing nonlinear element with co-rotational finite element method is proposed. Based on this framework, linear shell and beam element is easy to be extended to nonlinear problem analysis

Abstract: IGES (Initial Graphics Exchange Standard) is a general graphics data exchange standard, which has been widely used for data exchange between different CAD/CAM systems. But the inherent defect of IGES makes it difficult to use in the field of automatic programming. This article focuses on the automatic programming of holes processing. Entities were labeled with different entity number, on which the hole entity could be distinguished and extracted based. The intersection lines of hole and NURBS surface could be calculated by NURBS surface intersection algorithm. The redundancy of intersecting lines is a key problem. This article gives an intuitive treatment.

Abstract: The in-pipe detector with magnetic flux leakage runs along the pipeline under the effect of gas flow field, completing the pipeline wall excitation, magnetic flux leakage testing, etc. Excitation within the detector on the wall and the adequacy of magnetic flux leakage signal acquisition is complete are decided by speed of in-pipe detector. In this paper, mathematical model simulation is established and the actual experiment is proposed. Simulation and experiment results show that after a long time running, in-pipe detector with different discharge area have respective upper speed limit. According to references and experiment results, the in-pipe detector with 40% discharge area is meet the detection accuracy and have the maximum detection efficiency under work conditions described in this paper

Abstract: Having investigated the application of industrial wireless gateway, this paper focuses on the designing of monitoring system in chemical water ultrafiltration system. This monitoring system is based on Zigbee wirelss communication technology and aims at the connecting between wireless sensor network and Profibus-Dp field bus. The design of operator station as well as hardware and software design for the valve terminal nodes and gateway are presented in detail.

Abstract: For the problem of difficult to detect the edge in the surface image processing, we used the Euclidean distance from the selected pixels in the corner of the neighborhood window to the centre point of that to measure the extent of being edge, and then search for suitable threshold to extract the expected edge pixels. This algorithm can extract target information better, while also inhibiting the background interference, and it is a good algorithm which is worthy of further exploration

Abstract: This thesis combines the vibration measurement technology with the computer technology. We focus on the research of real-time vibration measurement key technology which is basing on the computing grid. This thesis gave details in collecting the real-time vibration data on sight, and automatically uploading the real-time data without making any mistakes. We handed out a analyze method for the vibration data basing on grid.

Abstract: Based on the panel data of 29 provinces, municipalities and autonomous regions in China from 1995 to 2009, this paper uses non-parametric panel data models to mainly study the influences of coal, electricity, oil consumption to GDP. We find the following results: (1) local linear kernel estimation method shows that coal, electricity and oil consumptions have significant positive impacts on GDP; (2) the pointwise regression estimates of output elasticity for coal, electricity and oil consumptions with respect to five explanatory variables have shapes including “U”, inverted “U”, increasing and decreasing types