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91.
基于卡尔曼滤波的人脸跟踪算法   总被引:1,自引:1,他引:0  
针对实时视频监控领域中传统的Camshift算法不能自动跟踪人脸和容易受到肤色相近遮挡等问题,采用Ad-aboost算法实现了人脸的自动检测,同时对于跟踪丢失等情形,通过卡尔曼预测对跟踪偏差进行实时改进。实验表明跟踪的准确性有较大提高,具有较好的实时性;在相近肤色遮挡时仍能实现正确跟踪,并对侧脸也有较好的效果;算法具有较好的鲁棒性。  相似文献   
92.
随着多媒体与网络技术的迅速发展,大量的三维模型产生并被广泛使用,导致三维模型查询成为紧迫的研究内容。其中基于内容的三维模型特征提取是一个重要的研究课题。文章在研究现有三维模型特征提取算法的基础上,提出了一种改进的正视图特征提取算法,通过提取正视图的灰度统计量平均值、均方差和三阶矩为特征,提高了算法的精确度。实验表明,算法在获得较好查准率与查全率的同时,降低了算法的运行时间。  相似文献   
93.
采用红外跟踪、射频识别技术和数字式温度传感器等,设计制作了一套集目标定位跟踪和温度无线传输为一体的综合系统.阐述了该系统的硬件组成和软件设计方法,最后通过系统测试给出了测试结果.  相似文献   
94.
95.
从提高太阳能电池板的输出功率出发,提出了基于双CPU控制方式的太阳能跟踪系统。系统采用俯仰-水平双轴控制,以单片机STC12C2052AD为光电控制单元的核心处理器,以混合式步进电机为执行机构,以TMS320F2812为核心控制器件的三相正弦波细分驱动器实现了混合式步进电机的精确定位。实验表明系统运行稳定,具有很高的实用价值。  相似文献   
96.
针对实时视频监控领域中传统的Camshift算法不能自动跟踪人脸和容易受到肤色相近遮挡等问题,首先采用Adaboost算法实现了人脸的自动检测,同时对于跟踪丢失等情形,通过贪心预测和卡尔曼预测对跟踪偏差进行实时改进,并比较两种算法的优缺点。实验表明前者对跟踪的准确性有较大提高,后者具有较好的实时性,在相近肤色遮挡时仍能实现正确跟踪,并对侧脸也有较好的效果,算法具有较好的鲁棒性。  相似文献   
97.
Visual tracking technology can provide measurement information for unmanned helicopter formation and thus, more attention is being paid to this research area. We propose a novel mean shift (MS) algorithm that is both adaptive and robust for unmanned helicopter formation and apply it to the leading unmanned helicopter tracking. The movement of an unmanned helicopter is very flexible and changeable, which makes the tracking there of more difficulty than for common targets. In creating an algorithm that can adapt to the acceleration of the unmanned helicopter and estimates both the scale and orientation of the movement changes, we combine the traditional MS with the bio-inspired Cauchy predator-prey biogeography-based optimization (CPPBBO) evolutionary algorithm, and also the space variant resolution (SVR) mechanism of the human visual system (MS-CPPBBO-SVR). To demonstrate the effectiveness and robustness of the proposed method and justify the importance of the CPPBBO algorithm and SVR mechanism at the same time, a series of comparative exper- iments were carried out. The experimental results of the proposed MS-CPPBBO-SVR method are compared with other competitive tracking methods, such as MS, MS with SVR (MS-SVR), MS-SVR with several other optimization algorithms, and the robust particle filter algorithm. The experimental results demonstrate that our proposed tracking approach, MS-CPPBBO-SVR, is more adaptive, robust and efficient in target tracking than the other methods.  相似文献   
98.
The vector tracking algorithm uses a single extended Kalman filter (EKF) to predict the time-delays and the Doppler deviations of the GNSS signal, while also estimating the user's position, velocity, and clock state. In this paper, the effects of multipath on the tracking performance of the vector delay / frequency lock loop (VDFLL) is studied for better application in the multipath environment. The error expressions of the measurements are given in theory. The tracking error caused by multipath is reduced by VDFLL, which is proved by the tracking error of VDFLL through a new iterating method. The theoretical analysis is verified by the Monte Carlo simulation.  相似文献   
99.
In this paper, the control problem of continuous stirred tank reactors (CSTR) is studied. The considered CSTR are required to contain unknown functions and unknown dead zone input. An adaptive controller that uses the neural networks (NNs) is provided to solve the unknown terms. The proposed approach overcomes the effect of the dead zone input. The dead zone input in the systems is compensated for by introducing a new Lyapunov form and Young's inequality. The backstepping procedure is exploited to implement controller design with adaptation laws. The stability is analyzed using Lyapunov method. The performance is examined for CSTR to confirm the effectiveness of the proposed approach based on computer simulation.  相似文献   
100.
Real-time highway traffic monitoring systems play a vital role in road traffic management, planning, and preventing frequent traffic jams, traffic rule violations, and fatal road accidents. These systems rely entirely on online traffic flow info estimated from time-dependent vehicle trajectories. Vehicle trajectories are extracted from vehicle detection and tracking data obtained by processing road-side camera images. General-purpose object detectors including Yolo, SSD, EfficientNet have been utilized extensively for real-time object detection task, but, in principle, Yolo is preferred because it provides a high frame per second (FPS) performance and robust object localization functionality. However, this algorithm’s average vehicle classification accuracy is below 57%, which is insufficient for traffic flow monitoring. This study proposes improving the vehicle classification accuracy of Yolo, and developing a novel bounding box (Bbox)-based vehicle tracking algorithm. For this purpose, a new vehicle dataset is prepared by annotating 7216 images with 123831 object patterns collected from highway videos. Nine machine learning-based classifiers and a CNN-based classifier were selected. Next, the classifiers were trained via the dataset. One out of ten classifiers with the highest accuracy was selected to combine to Yolo. This way, the classification accuracy of the Yolo-based vehicle detector was increased from 57% to 95.45%. Vehicle detector 1 (Yolo) and vehicle detector 2 (Yolo + best classifier), and the Kalman filter-based tracking as vehicle tracker 1 and the Bbox-based tracking as vehicle tracker 2 were applied to the categorical/total vehicle counting tasks on 4 highway videos. The vehicle counting results show that the vehicle counting accuracy of the developed approach (vehicle detector 2 + vehicle tracker 2) was improved by 13.25% and this method performed better than the other 3 vehicle counting systems implemented in this study.  相似文献   
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