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排序方式: 共有2610条查询结果,搜索用时 15 毫秒
21.
研究了运动目标检测与跟踪的DSP(DigitalSignalProcessor)实现算法,以形心跟踪算法为整个处理系统的核心。采用目标形心跟踪算法,通过目标分割阶段的目标标记,如目标面积、周长、形心位置等信息的提取建立目标跟踪波门,实现目标的连续跟踪,并将此算法移植到sEED—VPM642硬件平台,实验结果表明能够达到预定目标。此外,为了克服形心算法的准确性和实时性缺陷,采用粒子滤波对算法进行必要的扩展,从MATLAB的仿真结果看,除个别采样点存在误差较大的情况,真实值曲线与粒子滤波跟踪曲线拟合较好。 相似文献
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Distributed match-making 总被引:1,自引:0,他引:1
In many distributed computing environments, processes are concurrently executed by nodes in a store- and-forward communication network. Distributed control issues as diverse as name server, mutual exclusion, and replicated data management involve making matches between such processes. We propose a formal problem called distributed match-making as the generic paradigm. Algorithms for distributed match-making are developed and the complexity is investigated in terms of messages and in terms of storage needed. Lower bounds on the complexity of distributed match-making are established. Optimal algorithms, or nearly optimal algorithms, are given for particular network topologies.The work of the second author was supported in part by the Office of Naval Research under Contract N00014-85-K-0168, by the Office of Army Research under Contract DAAG29-84-K-0058, by the National Science Foundation under Grant DCR-83-02391, and by the Defence Advanced Research Projects Agency (DARPA) under Contract N00014-83-K-0125. Current address of both authors: CWI, Kruislaan 413, 1098 SJ Amsterdam, The Netherlands. 相似文献
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徐祖明 《武汉冶金管理干部学院学报》2006,16(2):74-77
本文运用比较的方法,论述了雨果的“美丑对照原则”与波德莱尔“以丑为美”理论的异同,并以他们各自的创作实践说明了这两种理论的运用都没有改变事物(描写的对象)的本质,只是在一定程度上改变了事物的原有面貌;它们都是对客观事物的具体反映和直接把握,是艺术家对人性善和美的异曲同工的追求,为人们提供了全面的艺术范例和审美观念。 相似文献
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《Expert systems with applications》2014,41(1):137-155
The emergence of the RFID technology and its application to supply chain processes has in particular led to the creation of such standards as the EPCglobal’s model of supply networks as a tool for materializing intra- and inter-enterprise visibility of resources and products, collaboration and integration. Among other critical uses, RFID has been deployed by supply networks to improve asset utilization, effectively combat counterfeiting, and advance targeted product recalls. However, new affordable and deployable technologies and microsensors have recently appeared and keep maturing. This paper discusses the needs and the possibilities that exist for leveraging these technologies and sensors with RFID to guarantee continuous and seamless visibility of all assets (fixed and mobile resources and field personnel) of smart enterprises, thereby expanding and complementing the roles of RFID. It examines the design challenges for the integration of these technologies for advanced logistics operations at the level of product classes or their instances. It then outlines our development of an embedded microsystem that combines RFID, GPRS, GPS and environmental sensors for applications in logistics. The prototyped microsystem demonstrated the feasibility of the multi-sensor integration paradigm that the paper proposes. 相似文献
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The paper presents a new approach for recommending suitable learning paths for different learners groups. Selection of the learning path is considered as recommendations to choosing and combining the sequences of learning objects (LOs) according to learners’ preferences. Learning path can be selected by applying artificial intelligence techniques, e.g. a swarm intelligence model. If we modify and/or change some LOs in the learning path, we should rearrange the alignment of new and old LOs and reallocate pheromones to achieve effective learning recommendations. To solve this problem, a new method based on the ant colony optimisation algorithm and adaptation of the solution to the changing optimum is proposed. A simulation process with a dynamic change of learning paths when new LOs are inserted was chosen to verify the method proposed. The paper contributes with the following new developments: (1) an approach of dynamic learning paths selection based on swarm intelligence, and (2) a modified ant colony optimisation algorithm for learning paths selection. The elaborated approach effectively assist learners by helping them to reach most suitable LOs according to their preferences, and tutors – by helping them to monitor, refine, and improve e-learning modules and courses according to the learners’ behaviour. 相似文献
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In this paper, we propose a discriminative multi-task objects tracking method with active feature selection and drift correction. The developed method formulates object tracking in a particle filter framework as multi-Task discriminative tracking. As opposed to generative methods that handle particles separately, the proposed method learns the representation of all the particles jointly and the corresponding coefficients are similar. The tracking algorithm starts from the active feature selection scheme, which adaptively chooses suitable number of discriminative features from the tracked target and background in the dynamic environment. Based on the selected feature space, the discriminative dictionary is constructed and updated dynamically. Only a few of them are used to represent all the particles at each frame. In other words, all the particles share the same dictionary templates and their representations are obtained jointly by discriminative multi-task learning. The particle that has the highest similarity with the dictionary templates is selected as the next tracked target state. This jointly sparsity and discriminative learning can exploit the relationship between particles and improve tracking performance. To alleviate the visual drift problem encountered in object tracking, a two-stage particle filtering algorithm is proposed to complete drift correction and exploit both the ground truth information of the first frame and observations obtained online from the current frame. Experimental evaluations on challenging sequences demonstrate the effectiveness, accuracy and robustness of the proposed tracker in comparison with state-of-the-art algorithms. 相似文献