This Paper presents a novel scheme for extracting the key moving objects in picture in picture news video. In this kind of video, some moving objects undergo the static camera while the others do not. Actually it is v...
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ISBN:
(纸本)8955191197
This Paper presents a novel scheme for extracting the key moving objects in picture in picture news video. In this kind of video, some moving objects undergo the static camera while the others do not. Actually it is very difficult for computer to distinguish whether the motion is caused by the moving objects themselves or the moving camera by the frame difference only. So in the paper, the fast, automatic and robust anchorperson extraction is achieved by the simple anchorperson model. The experimental results demonstrate good performances.
Gas sensors provide the artificial sense of smell for a mobile robot to track an airborne gas/odor plume and to locate its source. However, a slow response of gas sensors has been the major factor limiting the develop...
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Gas sensors provide the artificial sense of smell for a mobile robot to track an airborne gas/odor plume and to locate its source. However, a slow response of gas sensors has been the major factor limiting the development of plume-tracking robots. This paper describes a new control algorithm that overcomes the limitation. The basic idea is to detect the onset of a gas sensor response and start recovery by monitoring the relative change in each sensor output. Fast plume tracking is accomplished by making the robot take appropriate actions immediately when the sensor outputs start changing from one state to another. The detection of output change also leads to reliable plume detection and comparison of multiple sensor outputs since it is less affected by drift or sensitivity mismatch than the previous algorithm based on the absolute levels of sensor outputs. Experimental results have shown that the robot can track down a gas source within the distance of 2 m in 30 s even though semiconductor gas sensors with a long recovery time (> 60 s) are used.
In many hybrid wireless sensor networks (HWSNs) applications, sensor nodes are deployed in hostile environments where trusted and un-trusted nodes co-exist. In such hybrid networks, it becomes important to allow trust...
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In many hybrid wireless sensor networks (HWSNs) applications, sensor nodes are deployed in hostile environments where trusted and un-trusted nodes co-exist. In such hybrid networks, it becomes important to allow trusted nodes to share information, especially, location information and, at the same time, prevent un-trusted nodes from gaining access to this information. We focus on anchor-based localization algorithms in HWSNs, where a small set of specialized nodes, i.e. anchor nodes, broadcast their location to the network and other nodes can use the broadcast information to estimate their own location. The main challenge is that both trusted and un-trusted nodes can measure the physical signal transmitted from anchor nodes. Thus, un-trusted nodes can use the physical signal transmitted from an anchor node to estimate its location. In this paper, we propose hidden anchor, an algorithm that provides anchor physical layer location privacy. The hidden anchor algorithm exploits the inherently noisy wireless channel and uses identity cloning of neighboring trusted nodes to make anchors unobservable to untrusted nodes while providing complete information to trusted nodes. Evaluation of the hidden anchor algorithm through analysis and simulation shows that it can hide the location and identity of anchor nodes with very low overhead.
This paper proposes an inverse-time-lag algorithm combined with one-step inertia filtering algorithm on the analysis of load fluctuation of beaming-pumping and the reason why it occurs in oilfield, taking an example o...
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This paper proposes an inverse-time-lag algorithm combined with one-step inertia filtering algorithm on the analysis of load fluctuation of beaming-pumping and the reason why it occurs in oilfield, taking an example of power detection of beaming-pumping unit related to oilfield load fluctuation. A close loop controller based on this theory enabled the generator to change its working condition and thus the output can be increased or decreased automatically. The effect of energy saving is remarkable.
In this paper we consider multi-user detection in CDMA systems. A modified recursive least squares (RLS) Blind adaptive algorithm for multiuser detection in multipath channels is proposed. The proposed algorithm is sh...
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In this paper we consider multi-user detection in CDMA systems. A modified recursive least squares (RLS) Blind adaptive algorithm for multiuser detection in multipath channels is proposed. The proposed algorithm is shown to have a lower computational complexity than the conventional RLS algorithm while maintaining the same performance as the conventional RLS algorithm. Also, we propose a blind adaptive RLS algorithm that is used for multiuser detection of the high rate users in dual rate DS/CDMA systems in multipath (MP) fading channels. The new algorithm gives the same performance as the previously studied cyclic RLS algorithms. However, it has a significantly lower computational complexity.
Use of the recursive least-squares algorithm to track parameters that may undergo slow or sudden changes requires refinements to prevent excessive gain decay and the loss of the ability to re-identify parameters. A te...
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Use of the recursive least-squares algorithm to track parameters that may undergo slow or sudden changes requires refinements to prevent excessive gain decay and the loss of the ability to re-identify parameters. A technique in wide-spread use developed by Fortescue, Kershenbaum and Ydstie (1981) involves variable weighting of past data based on the squared output error through a scalar forgetting factor that divides the covariance matrix. This can slow convergence when only a single parameter is changed because the forgetting factor affects all covariance elements equally. A modification is proposed that replaces the scalar forgetting factor by a diagonal forgetting matrix that contains directional information. This directional information is provided by the relative magnitude of the sum of errors squared for one-parameter estimates over a finite time window. Simulations with single parameter changes showed improved convergence; while multiple parameter variations showed, at worst, comparable performance to the unmodified algorithm.
In this paper, we consider the problem of detecting and tracking moving sources emitting wideband signals under the severe spatial aliasing condition in sparse passive arrays. We develop direction of arrival (DOA) est...
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In this paper, we consider the problem of detecting and tracking moving sources emitting wideband signals under the severe spatial aliasing condition in sparse passive arrays. We develop direction of arrival (DOA) estimation algorithm based on subband MUSIC (multiple signal classification) method which produces high-resolution estimation and the fact that true bearings are invariant regardless of a change of frequency bands while the aliased false bearings vary. Despite its simplicity, the proposed algorithm overcomes the aliasing effects and improves the localization performance in sparse passive arrays. Simulation results for multiple target tracking are presented and the robustness algorithm with respect to measurement noise is also demonstrated.
A ball detection and tracking approach in real soccer game is proposed in this paper. In view of difficulties of direct detection, an indirect strategy based on non-ball elimination is applied. We distinguish the ball...
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ISBN:
(纸本)0769521282
A ball detection and tracking approach in real soccer game is proposed in this paper. In view of difficulties of direct detection, an indirect strategy based on non-ball elimination is applied. We distinguish the ball with a coarse-to-fine process. Game field is firstly extracted and the posterior operations are restricted within it. Then, at the coarse step, some distinct non-ball regions are removed via evaluation of color and shape. And at the fine step, the remained regions are further examined and the optimal one is determined as ball. Afterwards. CONDENSATION algorithm is utilized to track ball. Region optimization is appended to adapt to the ball's size and color/texture changes in response to movement along sequential frames through maximizing the normalization sum of intensity gradient around its perimeter. Moreover, a confidence measure representing the ball region's reliability is presented to guide possible re-detection for continuous tracking. Experiments have demonstrated the method is valid and fast in real soccer sequences.
A novel acoustic echo canceller for speakerphone system based upon iterative maximal length correlation (IMLC) algorithm is proposed. This algorithm is robust to double talk because of the nature of the ML sequence; i...
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A novel acoustic echo canceller for speakerphone system based upon iterative maximal length correlation (IMLC) algorithm is proposed. This algorithm is robust to double talk because of the nature of the ML sequence; it also iteratively reduces the far-end speech's effects. This simple structure was found to perform very well. We also perform a rigorous convergence analysis and derive the lower bound for the coefficient error. Computer simulations also confirm our theoretical results.
This paper proposes a novel fast scheme to deal with multiple motion video, which contains more than one different motion objects. changedetection methods are employed under some essential prior knowledge, and the co...
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ISBN:
(纸本)0780377028
This paper proposes a novel fast scheme to deal with multiple motion video, which contains more than one different motion objects. changedetection methods are employed under some essential prior knowledge, and the computing complexity is low. Experimental results show that the presented algorithm performs well for the multiple motion video, efficiently and effectively.
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