Global registration is an important step in the three-dimensional reconstruction of multi-view laser point clouds for moving objects, but the severe noise, density variation, and overlap ratio between multi-view laser point clouds present significant challenges to global registration. In this paper, a multi-view laser point cloud global registration method based on low-rank sparse decomposition is proposed. Firstly, the spatial distribution features of point clouds were extracted by spatial rasterization to realize loop-closure detection, and the corresponding weight matrix was established according to the similarities of spatial distribution features.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
September 2011
A novel kind of carbon nanotubes/titanium dioxide (CNTs/TiO2) composite photocatalyst was prepared by a modified sol-gel method in which the nanoscaled TiO2 particles were uniformly deposited on the CNTs modified with poly(vinyl pyrrolidone) (PVP). The composites were characterized by a range of analytical techniques including high resolution transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The results show the successful covering of the CNTs with PVP, forming core-shell structure.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
August 2011
Hydrous oxides of cerium, aluminum, nickel and copper were prepared by alkaline precipitation method. Langmuir adsorption isotherm was studied and specific surface area was measured by BET method through N2 adsorption-desorption process. IR characterization of hydrous metal oxides before and after fluoride adsorption was also studied.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
January 2011
Ferrocene was used as a catalyst, and xylene as carbon source. Chemical vapor deposition method was used to synthesize carbon nanotubes (CNTs). The CNTs were treated by oxidation method with concentrated nitric acid.
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