MULTIPARAMETER MEASUREMENT FOR RACEWAY GROOVE OF BEARING BASED ON 3D RECONSTRUCTION WITH DIGITAL STRUCTURED LIGHT

A fast 3D reconstruction method based on structured light to measure various parameters of the raceway groove is presented. Digital parallel grating stripes distributed with sine density are projected onto the raceway groove by a DLP projector, and distorting of stripes is happened on the raceway. Simultaneously, aided by three-step phase-shifting approach, three images covered by different stripes are obtained by a high-resolution CCD camera at the same location, thus a more accuracy local topography can be obtained. And then the bearing is rotated on a high precision computer controlled rotational stage. Three images are also obtained as the former step at next planned location triggered by the motor. After one cycle, all images information is combined through the mosaics. As a result, the 3D information of raceway groove can be gained. Not only geometric properties but also surface flaws can be extracted by software. A preliminary hardware system has been built, with which some geometric parameters have been extracted from reconstructed local topography.

Projects Lists Relating to Post-disaster Reconstruction

Aba Prefecture Company Name:Sichuan Xintong New Materials Co.Ltd. Address:Shuimo,Wenchuan Nature of Business:Private Project Name:Processing and Sale of Tourism Products Details:Producing and processing of Natural crystal products,man-made gem and other

Discussion on the Safe and Guaranteed Access of Interchange Widening in Reconstruction and Extension of Highway

In the process of reconstruction and extension of highways,the most important thing is to ensure that the overall level of the widening of interchanges is comprehensively improved to ensure safe traffic.However,due to the heavy and difficult tasks in the widening of interchanges,higher requirements are put forward for the construction quality of the project.In the actual construction of the project,it is necessary to actively analyze and explain the specific construction of the interchange widening project to ensure that the improvement level of the interchange widening in highway reconstruction and extension project is effectively upgraded.This paper gives a detailed introduction to the main construction technology for interchange widening project,clarifies the technical points of safety and guaranteed access,and proposes corresponding safeguard measures to ensure the comprehensive upgrade of the construction quality and standard of interchange widening in highway reconstruction and extension.

Study on Criterion of Differential Settlement in Subgrade Widening Project of an Expressway

Criterion of differential settlement in subgrade is useful for keeping road in a good serving condition. The theory of traditional materials strength and their technologic economy are applied to analyze the additional bend stress of the pavement structure, the equivalent beam of elastic foundation and influence on the pavement structure of an uneven settlement. The allowable settling ratio of pavement index （ △i ） is got and is used to appraise the uneven settlement standard value in subgrade. The allowable settling ratio of pavement index is applied in an certain widening expressway project and △i ≤0.36 % is attained by the analyzing, calculating and adding a certain safe coefficient. This value was put into practice and is effective during the past two years.

Geometric matrix research for nuclear waste drum tomographic gamma scanning transmission image reconstruction

A geometric matrix model of nuclear waste drums is proposed for transmission image reconstruction from tomographic gamma scans（TGS）. The model assumes that rays are conical, with intensity uniformly distributed within the cone. The attenuation coefficients are centered on the voxel（cube） of the geometric center. The proposed model is verified using the EM algorithm and compared to previously reported models. The calculated results show that the model can obtain good reconstruction results even when the sample models are highly heterogeneous.

Development of projection-type optical scheme for computer-generated Fourier hologram recorder

Projection-type recorders of computer-generated Fourier holograms have potential due to the decreased precision requirements of the optical scheme compared to most known holographic data recorders based on two-beam schemes.In the case of optical memory system development,the reduction factor of the projection scheme requires the application of properly developed optical components.The present report is dedicated to the development of special objectives for the projection scheme of computer-generated Fourier holograms.