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971.
Vanishing point detection algorithms based on 2D histogramming techniques have been employed in a variety of computer vision systems. Previous algorithms achieved some good results but still failed to maintain a balanced performance in both accuracy and time. Recent research (Li et al., 2010) shows that, vanishing point detection could be converted to a 1D histogram search problem, which largely accelerates the procedure. In this paper, we further improve this idea and propose a complete scheme for vanishing point detection from images of the so called “Manhattan world”. We test our algorithm and some commonly used vanishing point detection methods on public database YorkUrbanDB and our own implemented database PKUCampusDB. Our algorithm shows significant performance improvements. 相似文献
972.
Pinning a stochastic neural network to the synchronous state 总被引:1,自引:1,他引:0
In this paper, the asymptotic stability of the pinning synchronous solution of stochastic neural networks with and without
time-delays is analyzed. The delays are time-varying, and the uncertainties are norm-bounded that enter into all the parameters
of network and control. The aim of this paper is not only to establish easily verifiable conditions under which the pinning
synchronous solution of stochastic neural network is globally asymptotically stable but also to give a feasible way to offset
the limitation of network itself in order to reach synchronization. In addition, a specific neurobiological network is also
introduced, and some numerical examples are provided to illustrate the applicability of the proposed criteria. 相似文献
973.
Nowadays video surveillance systems are widely deployed in many public places. However, the widespread use of video surveillance
violates the privacy rights of the people. Many authors have addressed the privacy issues from various points of view. In
this paper we propose a novel, on-demand selectively revocable, privacy preserving mechanism. The surveillance video can be
tuned to view with complete privacy or by revoking the privacy of any subset of pedestrians while ensuring complete privacy
to the remaining pedestrians. We achieve this by tracking the pedestrians using a novel Markov chain algorithm with two hidden
states, detecting the head contour of the tracked pedestrians and obscuring their faces using an encryption mechanism. The
detected pedestrian face/head is obscured by encrypting with a unique key derived from a master key for the privacy preservation
purpose. The performance evaluations on many challenging surveillance scenarios show that the proposed mechanism can effectively
and robustly track as well as identify multiple pedestrians and obscure/unobscure their faces/head in real time. 相似文献
974.
A supervised polarimetric SAR land cover classification method was proposed based on the Fisher linear discriminant.The feature parameters used in this classification method could be selected flexibly according to land covers to be classified.Polarimetric and texture feature parameters extracted from co-registered multifrequency and multi-temporal polarimetric SAR data could be combined together for classification use,without consideration of the dimension difference of each feature parameter and the joint probability density function of those parameters.Experimental result with AGRSAR L/C-band full polarimetric SAR data showed that a total classification accuracy of 94.33% was achieved by combining the polarimetric with texture feature parameters extracted from L/C dual band SAR data,demonstrating the effectiveness of this method. 相似文献
975.
976.
Based on the state-of-the-art studies of solar-soil source heat pump compound system, operation patterns of solar-soil compound
system were analyzed, particularly the advantages of parallel operation pattern. It is found that parallel operation pattern
is better for solar-soil compound system. Furthermore, the heat balance issue of solar-soil compound system was emphatically
analyzed from four aspects, which were annual analysis of heating and cooling load, the heat exchange of ground heat exchanger,
capacity determination of solar-assisted heat source and heat balance calculation of solar-soil compound system. Moreover,
annual rate of heat balance in a solar-soil source heat pump compound system was calculated with a case study. It is shown
that the annual heat unbalance ratio is 19%, which is less than 20%. As a result, the practical solar-soil compound system
can basically maintain the heat balance of soil. 相似文献
977.
Mg-6%Al-5%Pb (mass fraction) anodes with different contents of zinc were prepared by melting and casting. The electrochemical
discharge behavior of these anodes in 3.5% NaCl solutions was investigated by galvanostatic test and electrochemical impedance
spectroscopy (EIS). The microstructures and the corroded surfaces of these anodes were studied by scanning electron microscopy
(SEM) and emission spectrum analysis (ESA). The phase structures and the corrosion products of the anodes were analyzed by
X-ray diffraction (XRD). The results show that zinc promotes the grain refinement of Mg-6%Al-5%Pb anode and makes the average
discharge potential of Mg-6%Al-5%Pb anode more negative during galvanostatic test. Mg-6%Al-5%Pb anode with the addition of
1% (mass fraction) zinc has the best electrochemical performance. The activation mechanism of zinc to Mg-6%Al-5%Pb anode is
as follows: The hydrolyzation of dissolved Zn2+ ions reduces the pH value of the solution near the surface of the anode and accelerates the dissolution of Mg(OH)2 film; The precipitated Zn(OH)2 with similar structure as Mg(OH)2 combines with Mg(OH)2 film easily and makes it break down. 相似文献
978.
In order to meet the severe requirements of market and reduce production costs of high quality steels, advanced run-out table
cooling based on ultra fast cooling (UFC) and laminar cooling (LC) was proposed and applied to industrial production. Cooling
mechanism of UFC and LC was introduced first, and then the control system and control models were described. By using UFC
and LC, low-cost Q345B strips had been produced in a large scale, and industrial trials of producing low-cost dual phase strips
were completed successfully. Application results show that the ultra fast cooling is uniform along the strip width and length,
and does not affect the flatness of strips. The run-out table cooling system runs stably with a high precision, and makes
it possible for the user to develop more high quality steels with low costs. 相似文献
979.
To get the scattering loss of the trapezoidal core waveguide, a new analysis model is presented based on the perturbation
equivalent method and modified effective-index method. Firstly, the trapezoidal core waveguide is successfully equivalent
to the rectangular one with both restricting the same optical field energy by adopting the perturbation method. Then, the
equivalent rectangular core waveguide is decomposed into two slab waveguides by employing the modified effective-index method.
The trapezoidal core waveguide scattering theory model is established based on the slab waveguide scattering theory. With
the sidewalls surface roughness in the range from 0 to 100 nm in the single model trapezodial core waveguide, optical simulation
shows excellent agreement with the results from the scattering loss model presented. The relationship between the dimension
and side-wall roughness with the scattering loss can be determined in the trapezoidal core waveguide by the scattering loss
model. 相似文献
980.