In this paper, a novel stereoscopic video surveillance system to track a target person and detect its three-dimensional (3D) location coordinates and moving trajectory is implemented by using the pan/tilt-controlled stereo camera system. Stereoscopic video images of a target person are captured with stereo camera system and the target face and its location in the left image plane can be detected by use of YCbCr color model and centroid method. Also the target location in the right image plane can be obtained through correlation between the left face image and the right image by using the binary phase extraction joint transform correlator (BPEJTC) algorithm. With these location data of the target face in the left and right image planes the pan/tilt systems can control the stereo camera to track a target person by positioning the target face at the center of the camera’s FOV and making the focusing points of the right and left camera coincided on the target face. And then, with the resultant pan/tilt angles and geometric parameters of the stereo camera system, the target’s real 3D location coordinates and moving trajectory in the world space can be obtained. From some experiments with 900 frames of stereoscopic video image pairs, it is analyzed that the target’s center location after being tracked is kept to be very low error ratio of 0.62%, 2.04% on the average in the x, y directions of the image plane, respectively. Also, the error ratio between the calculated and measured values of the 3D location coordinates of a target person is found to be very low value of 2.1%, 5.7% on the average in the X and Y directions of the real world space, respectively. 相似文献
Recent measurements show substantial differences in levels of Reynolds stress in otherwise nominally similar separations. No explanation for these differences is know, but it appears they are not associated with end effects. End effects appear to be significant only for unexpectedly small flow width. 相似文献
The ionic complex of mesitoyl bromide with aluminum bromide in a 1∶1 composition (Mst-1) does not initiate the isobutylene
polymerization inn-hexane or methylene dichloride at −78 °C. The corresponding ionic complex of the 1∶2 composition (Mst-2) acts as a cationogenic
initiator of the polymerization. The addition of excess Lewis acid or introduction of organic electron acceptors increases
the initiating activity of the Mst-1 complex and activates acyl complexes of the 1∶2 composition including Mst-2. The results
are discussed in terms of the effect of specific solvation on the nucleophilicity of counteranions, which makes the addition
of the monomer to the carbocation possible.
For Part 9, see Ref. 1.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 52–56, January, 1998. 相似文献
The various end‐to‐end distances of four‐junction polymers are investigated. The sizes of the different kinds of equal length branches and the backbone of two different polymers, with either nine or eleven branches, are estimated by means of both renormalization‐group and MC calculations. The comparisons of first‐order ε = 4 − d predictions with the MC results are satisfactory. The same trends are present in both techniques. The excluded‐volume interactions from additional branches further expand the various parts of the chains so that internal branches are larger than external ones. The branch ratios in the eleven‐branch case are expanded even more than the corresponding ratios of the nine‐branch polymer.