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The gains in surveillance information that can be provided by fusion of multiple sensors have been demonstrated in theoretical and practical terms. However, the use of additional sensors quickly reaches a point where the marginal benefits outweigh the marginal costs. In part, this is due to an increasing probability of misassociation. Additionally, the probability of finding an available sensor with...
Risk-sensitive filter is a robust and numerically efficient algorithm compared to risk neutral filter with model uncertainties. For nonlinear plant, the square root unscented Kalman risk-sensitive filter (SUKRSF) is proposed in this paper by using unscented transformation approximation. Square root unscented Kalman filter (SRUKF), a derivative-free nonlinear estimation tool is used to solve risk-sensitive...
Reports generated by soldiers are common in time-critical military environments. Data fusion systems that attempt to process those reports must maintain the context for each set of observations to avoid inaccurate state estimates. This paper analyzes the selection and assignment of topical context under a Bayesian methodology. We present several techniques to decrease the hypothesis space and heuristics...
In this paper a new method of detecting and tracking a human person in three dimensional space using audio and video data is proposed. A simple tracking system with two microphones and stereo vision is introduced. The audio information is resulting from the generalized cross correlation (GCC) algorithm, and the video information is extracted by the continuously adaptive mean shift (CAMshift) method...
We consider a pair of correlated processes in {Zn}n=-infininfin and {Zn}n=-infininfin, where the former is observable and the latter is hidden. The uncertainty in the estimation of Sn upon the finite past history of Z0n-infin1 is H(Sn|)Z0ninfin1 which is a sequence of n. The limit of Cesaro mean of this sequence is called the estimation entropy. We show that the estimation entropy is the long...
Given a map of a polygon-shaped search area with obstacles and a group of mobile networked observers equipped with radiation dose counters (such as the Geiger-Muller counter), the data fusion problem is twofold: (1) to establish if any radioactive point sources are present in the area; (2) if present, to determine their number and their parameters (locations and intensities of radiation). The detection/estimation...
The reception state of a satellite is an unavailable information for Global Navigation Satellite System receivers. His knowledge or estimation can be used to evaluate the pseudorange error. This article deals with the problem using three reception states: direct reception, alternate reception and blocked situation. This parameter, estimated using a Dirichlet distribution, is included in a particle...
The probabilistic multi-hypothesis tracking (PMHT) algorithm has been successfully applied to a simulated multi-static active sonar data set that contains a single constant velocity target in varying amounts of clutter [1]. The simulated data set in that study contained negligible registration error was therefore easily registered to a common frame of reference for use in a centralized tracking architecture...
This paper presents a framework for pixel-level multisensor image fusion algorithm using graphics hardware. When it comes to the fusion technology of recent times, not only its visibility through information maximization which is brought about by the progress in sensor technology but also the importance of fusion processing speed has increased. The GPU provides high-performance compared to its price...
Heavy-tailed exponential distribution is a direct and necessary extension of the heavy-tailed Rayleigh distribution. First, some basic properties of heavy-tailed exponential distribution are introduced in this paper including the series form of the density function, the heavy-tailed property and the non-existence of finite variance. Second, ratio estimator, logarithmic moment estimator and iterative...
This paper presents a regularized least squares method to estimate the location and release rate of atmospheric pollution. We assume that measured pollution concentration at different ground locations and meteorological conditions such as wind speed are available so that one can solve the advection-diffusion equation for a non-steady point source. However, even finding linear parameters related to...
Active and passive sonar sensors provide complementary information about contacts. In addition to the physical characteristics of a passive array, the bearing resolution estimate can be limited by computational constraints given the necessity to survey the full azimuth for contacts. In a distributed field of sensors, however, it may be advantageous to divert the resources of a given sensor from a...
Numerous national and multinational initiatives in maritime surveillance have been initiated, with the goal of having knowledge of all coastal and open-seas activities relevant to national security. As part of this effort, NATO is pursuing research activities to exploit existing multi-sensor systems in support of maritime surveillance. Multi-sensor fusion of data from maritime surveillance assets...
The demand for the prevention of collateral damages in military operations requires methods of robust automatic identification of targets like vehicles especially during target approach. This requires the development of sophisticated techniques for automatic and semi-automatic interpretation of sensor data. In particular, the pre-analysis of reconnaissance data is important for the human observers...
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