An imbalanced and small training sample can cause an incident detection model to have a low detection rate and a high false alarm rate. To solve the scarcity of incident samples, a novel incident detection framework is proposed based on generative adversarial networks (GANs). First, spatial and temporal rules are presented to extract variables from traffic data, which is followed by the random forest algorithm to rank the importance of variables.
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February 2018
This paper proposes a novel 3-D surface profile measurement scheme by only a single-shot color binary speckle pattern (CBSP) and a temporal-spatial correlation matching algorithm, which can be applied to measurements of dynamic and static objects. R/G/B channels of CBSP are coupled with three carefully designed black and white binary speckle patterns (BWBSPs), whose physical features are associated with the system configuration parameters. We mathematically deduce the concrete details of how to design such a pattern and its relationship with the system parameters selected in the experiment.
View Article and Find Full Text PDFThree-dimensional (3D) acquisition of an object with modest accuracy and speed is of particular concern in practice. The performance of digital sinusoidal fringe pattern projection using an off-the-shelf digital video projector is generally discounted by the nonlinearity and low switch rate. In this paper, a binary encoding method to encode one computer-generated standard sinusoidal fringe pattern is presented for circumventing such deficiencies.
View Article and Find Full Text PDFTo determine the shape of a complex object with vertical measurement mode and higher accuracy, a novel modulation measuring profilometry realizing auto-synchronous phase shifting and vertical scanning is proposed. Coaxial optical system for projection and observation instead of triangulation system is adopted to avoid shadow and occlusion. In the projecting system, sinusoidal grating is perpendicular to optical axis.
View Article and Find Full Text PDFAn advanced Phase Measuring Deflectometry(PMD) is proposed to measure the three dimensional (3D) shape of the aspheric mirror. In the measurement process, a liquid crystal display(LCD)screen displaying sinusoidal fringe patterns and a camera observing the fringe patterns reflected via the tested mirror, are moved along the tested mirror optical axis, respectively. At each movement position, the camera records the fringe patterns of the screen located at two different positions.
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