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81.
Ke-Yan Liu Yun-Hua Li Shanqing Li Liang Tang Lei Wang 《Journal of Real-Time Image Processing》2012,7(3):153-163
This paper proposed a multi-cue-based face-tracking algorithm with the supporting framework using parallel multi-core and one Graphic Processing Unit (GPU). Due to illumination and partial-occlusion problems, face tracking usually cannot stably work based on a single cue. Focusing on the above-mentioned problems, we first combined three different visual cues??color histogram, edge orientation histogram, and wavelet feature??under the framework of particle filters to considerably improve tracking performance. Furthermore, an online updating strategy made the algorithm adaptive to illumination changes and slight face rotations. Subsequently, attempting two parallel approaches resulted in real-time responses. However, the computational efficiency decreased considerably with the increase of particles and visual cues. In order to handle the large amount of computation costs resulting from the introduced multi-cue strategy, we explored two parallel computing techniques to speed up the tracking process, especially the most computation-intensive observational steps. One is a multi-core-based parallel algorithm with a MapReduce thread model, and the other is a GPU-based speedup approach. The GPU-based technique uses features-matching and particle weight computations, which have been put into the GPU kernel. The results demonstrate that the proposed face-tracking algorithm can work robustly with cluttered backgrounds and differing illuminations; the multi-core parallel scheme can increase the speed by 2?C6 times compared with that of the corresponding sequential algorithms. Furthermore, a GPU parallel scheme and co-processing scheme can achieve a greater increase in speed (8×?C12×) compared with the corresponding sequential algorithms. 相似文献
82.
开关柜误操作造成的事故越来越成为影响电力行业安全生产的主要事故类型之一。鉴于此,文章研究了一套智能高压开关柜自动识别系统。本系统中开关柜侧的装置在柜门被打开时可播放语音提示信息,并将开关柜开门关门等事件通过PT2262编码,再无线发送传输到后台。后台接收后,经F330单片机软件解码,并在触摸屏上记录事件的类型和时间。该系统对防止由于工作人员选错开关柜造成的误操作有一定的效果。 相似文献
83.
离散Hartley变换是一种有用的实值正交变换。文中对其快速算法进行研究,首先介绍利用算术傅里叶变换(AFT)计算离散傅里叶变换(DFT)可使其乘法计算量仅为O(N),然后文章根据这一特点,分析离散Hartley变换(DHT)的结构特征,通过DFT将AFT和DHT建立了直接联系,提出了一种新的快速DHT算法。算法的计算复杂度能够达到线性O(N),且算法结构简单,公式统一且易于实现,并与其他快速算法进行了比较,分析可知在数据长度不是2的幂次方时,文中提出的算法的计算时间明显比其他算法的计算时间要小。实验结果也验证了文中算法的有效性,从而为DHT的快速计算开辟了新的思路和途径。 相似文献
84.
王茂 《电脑编程技巧与维护》2012,(8):92-93
色彩模式是在数字处理过程中处理色彩的基本标准,其是以颜色模型为基础,利用数字定量对颜色进行描述的方法。针对图形图像制作软件中的色彩模式进行分析。 相似文献
85.
随着国内厚板产量的增加,其市场竞争日趋激烈。为了更好的谋求发展,莱钢宽厚板厂在降低生产成本的同时,通过技术改造极大地提高产品的质量。因为板坯成材规格需要精确的长度数据,所以宽厚板板坯长度的精确测量就显得非常重要。本文主要介绍激光测速仪在轧机后测长系统中的应用。 相似文献
86.
Jiaming Mao Mingming Zhang Mu Chen Lu Chen Fei Xia Lei Fan ZiXuan Wang Wenbing Zhao 《计算机系统科学与工程》2021,39(3):373-390
The rapidly increasing popularity of mobile devices has changed the methods with which people access various network services and increased network traffic markedly. Over the past few decades, network traffic identification has been a research hotspot in the field of network management and security monitoring. However, as more network services use encryption technology, network traffic identification faces many challenges. Although classic machine learning methods can solve many problems that cannot be solved by port- and payload-based methods, manually extract features that are frequently updated is time-consuming and labor-intensive. Deep learning has good automatic feature learning capabilities and is an ideal method for network traffic identification, particularly encrypted traffic identification; Existing recognition methods based on deep learning primarily use supervised learning methods and rely on many labeled samples. However, in real scenarios, labeled samples are often difficult to obtain. This paper adjusts the structure of the auxiliary classification generation adversarial network (ACGAN) so that it can use unlabeled samples for training, and use the wasserstein distance instead of the original cross entropy as the loss function to achieve semisupervised learning. Experimental results show that the identification accuracy of ISCX and USTC data sets using the proposed method yields markedly better performance when the number of labeled samples is small compared to that of convolutional neural network (CNN) based classifier. 相似文献
87.
Bai Qingchun Wei Kai Zhou Jie Xiong Chao Wu Yuanbin Lin Xin He Liang 《The Journal of supercomputing》2021,77(9):9474-9493
The Journal of Supercomputing - Sentiment analysis in Danmaku video interaction aims at measuring public mood in respect of the video, which is helpful for the potential applications in behavioral... 相似文献
88.
Yang Shuo Mao Xinjun Wang Qiuzhen Huang Yuhong 《Journal of Intelligent and Robotic Systems》2021,103(1):1-17
Journal of Intelligent & Robotic Systems - In this work, we present a new mathematic model for the flight of a bird-scale flapping-wing aerial vehicle, in which the impacts of the wing inertia... 相似文献
89.
Applied Intelligence - Cooperative control is currently a challenging topic of crowded unmanned underwater vehicle (UUV) swarm. However, individual behavior conflict and chain-avalanche collision... 相似文献
90.
针对选煤厂运煤火车人工喷洒防冻液不均匀的问题,设计了一种基于CC-Link的火车皮防冻液自动喷洒系统。该系统采用CC-Link现场总线技术将多套喷洒装置和防冻液加压泵站构建成工业现场级控制网络,实现了各装置之间的联动和实时监控。实际应用表明,该系统避免了防冻液的浪费,提高了工作效率。 相似文献