Two-dimensional Reconstruction Method Research Articles

Identification of asphalt pavement transverse cracking based on 2D reconstruction of vehicle vibration signal and edge detection algorithm

Transverse cracking is related to asphalt pavement structural performance. However, the method for transverse cracks identification by vehicle vibration signal has hardly been applied because of an extremely low recognition accuracy. The study aims to precisely identify the pavement transverse cracks by vehicle vibration response. A two-dimensional reconstruction method that transformed the vehicle vibration signal into an image was proposed. Five edge detection operators were used to generate the features of vibration reconstruction images. Besides, this study combined two basic characteristics, Euler number, and total target area. Eight classification models based on the above two features were trained by the RUSBoost integrated classifier. The results showed that the classification model based on the Prewitt operator eight connected domain Euler number and the total target area performed excellently. The testing accuracy can reach 93.5%. The classification model presented in this study has an excellent effect on pavement transverse crack identification and feasibility.

Triple crossings of a string of magnetic islands at duskside magnetopause encountered by AMPTE/IRM satellite on 8 August 1985

[1] There have been a number of reports on the existence of pearl-like magnetic island structures at the magnetopause current layer based on the analyses of single spacecraft data and two-dimensional reconstruction method of solving the Grad-Shafranov equation as a spatial initial value problem. This paper presents an unusual event of multiple magnetopause crossings encountered by AMPTE/IRM satellite at the duskside equatorial plane on 8 August, 1985. In a total of 11 magnetopause crossings spanning for nearly 2 hours, crossing 3, 4, and 9 display similar features of a string of magnetic islands imbedded within the overall tangential discontinuity-like current layers. In these crossings, the deHoffmann-Teller velocities form approximately 90° from the magnetopause normal that the in-and-out magnetopause motion becomes subsiding for the satellite to pick up the pearl-like plasmoids with island width of about 6–12 ion inertial length. In particular, crossing 3 and 9 are 1 hour apart but have almost the same magnetopause normal and deHoffmann-Teller velocity as well as similar invariant axis. A region of cold plasma adjacent to the magnetopause within the magnetosphere, the low-latitude boundary layer, is seen in all three crossings.

Hidden one dimensionality in Fermi surfaces ofη−Mo4O11observed by Compton scattering experiments

We have investigated Fermi surfaces of a low-dimensional Mo oxide, $\ensuremath{\eta}\text{\ensuremath{-}}{\mathrm{Mo}}_{4}{\mathrm{O}}_{11}$, using Compton scattering. The Fermi surfaces projected onto the ${a}^{*}$ plane, obtained from the two-dimensional reconstruction method, show a good agreement with those predicted by a previous band-theory study. Hidden one dimensionality, which is the most important feature in explaining the charge-density wave behavior in this material, is clearly observed in the experimentally obtained Fermi surfaces.