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191.
To tackle the re-identification challenges existing methods propose to directly match image features or to learn the transformation of features that undergoes between two cameras. Other methods learn optimal similarity measures. However, the performance of all these methods are strongly dependent from the person pose and orientation. We focus on this aspect and introduce three main contributions to the field: (i) to propose a method to extract multiple frames of the same person with different orientations in order to capture the complete person appearance; (ii) to learn the pairwise feature dissimilarities space (PFDS) formed by the subspaces of similar and different image pair orientations; and (iii) within each subspace, a classifier is trained to capture the multi-modal inter-camera transformation of pairwise image dissimilarities and to discriminate between positive and negative pairs. The experiments show the superior performance of the proposed approach with respect to state-of-the-art methods using two publicly available benchmark datasets. 相似文献
192.
A study of spin dynamics based on simulations with the Polymorphic Tracking Code(PTC) is reported,exploring the dependence of the static polarization limit on various beam parameters and lattice settings for a practical RHIC lattice. It is shown that the behavior of the static polarization limit is dominantly affected by the vertical motion, while the effect of beam-beam interaction is small. In addition, the "nonresonant beam polarization"observed and studied in the lattice-independent model is also observed in this lattice-dependent model. Therefore,this simulation study gives insights of polarization evolution at fixed beam energies, that are not available in simple spin tracking. 相似文献
193.
This paper presents an enhanced method for detecting and tracking moving objects from an active camera image sequence using
active contour models. Such enhancements are: (1) Using best block matching instead of the conventional block matching technique
to locate the promising feature points in the current frame. (2) Developing a new algorithm for rejecting bad feature points
that affect negatively the background compensation process. (3) Applying a modified region growing and labeling algorithm
to extract moving objects then applying active contour models around these moving objects in order to take into account the
object inside this contour. Various factors are studied to measure the system performance and limitations. A comparison of
TNRAC and the conventional approach is conducted using both rigid and non-rigid objects in both indoor and outdoor scenes. 相似文献
194.
电视经纬仪跟踪测量中运动目标快速识别定位算法 总被引:6,自引:5,他引:1
为解决电视经纬仪跟踪测量系统中对运动目标快速识别定位的要求,在深入分析运动目标特性和电视经纬仪跟踪测量系统特点的基础上,利用经纬仪角度变化信息,对运动目标图像序列进行帧间差值计算以获得目标残差图,并基于残差图提出了一种新型的运动目标快速识别方法,大大减少了运算量. 结合中值滤波和图像二值化,实现了运动目标的快速定位. 通过对目标实测图像序列的实验, 结果证明:该算法具有快速、稳定、有效等优点,能够满足电视经纬仪跟踪测量系统对运动目标快速识别定位的要求. 相似文献
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198.
Robert A. Peters 《International Journal of Satellite Communications and Networking》1988,6(2):163-171
Burst errors in an optical intersatellite link (ISL) are short term (of the order of a millisecond) degradations of the link due to antenna mistracking. These errors degrade the average bit error rate (BER), decrease coding gain, complicate calculations of tracking accuracy, and give rise to concern about the quality of the link for carrying digital signals. After reviewing previous work on these topics, the digital performance of the link is examined in terms of how these considerations affect the ability of an optical ISL to meet ISDN (Integrated Services Digital Network) criteria for an ISL. A link with on-board regeneration is assumed. Since no allocation has yet been made for an ISL, an allocation of 25 per cent of the degradation permitted for the satellite link by CCITT Rec. G.821 and CCIR Rec. 614 is assumed here. It is found (1) that if the requirement derived from Rec. 614 is met, the requirements derived from Rec. G.821 are also met and (2) that an optical ISL should have little difficulty in meeting these requirements. 相似文献
199.
极值步进跟踪在车载移动卫星通信中的应用 总被引:1,自引:1,他引:0
本文介绍了记忆极值跟踪的原理、车载移动卫星通信跟踪系统的组成和软件设计以及对实际遇到的问题的处理。 相似文献
200.
To evaluate the performance of a scheme for monitoring forecasts that are generated by exponential smoothing, forecasters have traditionally used a simulation-based estimator of some characteristic of the associated run-length distribution. The most frequently cited performance measures are the average run length and the probability that the run length does not exceed a user-specified cut-off point. However, there is disagreement about the definition of run length that is appropriate in the context of forecasting. In this paper we use fundamental results from renewal theory to establish the precise relationships between conflicting formulations both of the average run length and of the probability density function for the run length. More generally we derive the asymptotic mean and the asymptotic distribution function of the forward recurrence time for both ordinary and delayed renewal processes whose interoccurrence distributions are arithmetic with a given span. We discuss the practical significance of these results in the context of forecasting. Our findings bear directly on the way in which simulation experiments should be designed and executed to compare alternative forecast monitoring schemes. 相似文献