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Detection cof multiple scatterers for localizing the targets is one of the key issues in SAR tomography. Recently, a Generalized Likelihood Ratio Test based on support estimation (Sup-GLRT) [10] has been presented. This test exhibits a high computational complexity. In this paper a modified approach for reducing computational complexity (Fast-Sup-GLRT) is proposed. The prime objective is to analyze...
In this paper, a statistical method of estimating the number of endmembers from hyperspectral images is proposed. A noncentra chi-squared distribution model is applied to calculate this number. Endmembers are important parameters in many hyperspectral detection algorithms based on Linear Mixture Model(LMM). The number of endmenbers is the only preset parameter and needed in some anomaly detectors...
The wavelength of synthetic aperture lidar (SAL) is very short; vibration of millimeter magnitude will significantly change the phase of echo signal and lead to the defocus of imaging in azimuth direction, so vibration estimation is a key step of SAL imaging. The existing Space Correlation Algorithm (SCA) used to estimate vibration of SAL is only suitable for the condition of narrow azimuth beam and...
In the field of subpixel target detection in hyperspectral images, there is well-documented current interest for identifying preferred background covariance matrix estimates, to be used in the formation of matched-filter detectors. In this work, for the first time, we study the case of local background covariance matrix estimation from SLIC-superpixel based coherent regions. Interestingly, our experiments...
Aiming at the problem how to express relevant relationship between multiple targets, we propose an approach based on the tracking-by-detection (TBD) strategy, where detections from the HOG classifier are regarded as image evidence. Focusing on the issue of localization uncertainty, data association based on greedy heuristics is executed iteratively to retrieve from the erroneous candidate locations...
Detecting stair region and estimating the distance from a camera to stair in a stair image is the fundamental step in the implementation of autonomous stair climbing navigation, as well as alarm systems for vision impaired people. In this paper, a framework is proposed for detecting the stair region from stair image utilizing some natural properties of stair. One unique property of them is, every...
Humans are increasingly cooperating with machinery/robots in a high number of domains and under uncontrolled conditions. When persons are interacting with machinery, they are exposed to distraction/fatigue, which can lead to dangerous situations. The evaluation of individual's attention and fatigue levels is highly needed in such situations. This is an important measurement to avoid the interaction...
Performance of cognitive network strongly depends on the effectiveness of primary (licensed) user (PU) detection. This paper introduces the algorithm for PUs signal detection based on Markov model of the PUs activity. It is shown that the developed PUs detection algorithm outperforms the conventional detector that maximizes likelihood.
In this paper, we investigate the problem of indoor positioning using visible light systems. The directional detector array we use is comprised of a number of receiving elements, each consisting of an aperture and a photo diode, which are arranged to offer good angular diversity, and can be implemented within a compact receiver structure [1]. The receiving elements receive the light from a number...
An experiment was conducted on a water treatment plant to investigate the effectiveness of using Kalman filter based attack detection schemes in a Cyber Physical System (CPS). Kalman filter was implemented with Chi-Square detector. Random, stealthy bias, and replay attacks were launched and results analysed. Analysis indicates that stealthy false data injection and replay attacks cannot be detected...
The estimation of experienced travel time in road networks stands for an important feature in Advanced Traveler Information Systems (ATIS). In the era of data availability, the dissemination of accurate traffic information to travelers could have a huge impact on their trip choices and thus in systems' performance. The scope of this paper is time travel modeling and prediction based on alternative...
By taking advantage of the difference in spatial distribution between underwater sound source and ocean ambient noise, a detector based on bearing estimation variance is proposed. The time delay estimation method is adopted to estimate the bearing of the source, and the test statistics is deduced to evaluate the performance of the detector. The results show that its performance is far superior to...
The terahertz band (0.3 to 3.0THz) has been found to be spectroscopically rich with many substances possessing strong and unique absorption signatures useful for chemical and biomedical sensing applications [1–4]. Photonics-based methods for spectrum analysis of the incident signal require complex time-domain spectroscopy systems achieving bandwidths more than 1THz but with resolution in GHz range...
Adaptive radar detection and estimation schemes are often based on the independence of the secondary data used for building estimators and detectors. This paper relaxes this constraint and deals with the non-trivial problem of deriving detection and estimation schemes for joint spatial and temporal correlated radar measurements. Latest results from Random Matrix theory, used for large dimensional...
We propose a weakly supervised method to arrange images of a given category based on the relative pose between the camera and the object in the scene. Relative poses are points on a sphere centered at the object in a given canonical pose, which we call object viewpoints. Our method builds a graph on this sphere by assigning images with similar viewpoint to the same node and by connecting nodes if...
In this paper, we propose an adaptive algorithm to detect and localize a point-like target in heterogeneous environments. At the design stage we use the two-step GLRT-based design procedure: we first introduce the GLRT for known structure of the noise covariance matrix and unknown noise levels, possibly different from one cell to another; then, we make the detector fully adaptive by replacing the...
The paper considers the composite detection problem where both detection and parameter estimation are of primary interest. Based on a Neyman-Pearson type of formulation, our goal is to find the joint detector and estimator that minimizes a decision-dependent Bayesian estimation risk subject to the detection error probability constraints. The optimal joint solution not only yields lower Bayesian estimation...
Region of interest (ROI) generation used to extract candidate windows which are likely to have pedestrians is an important step in pedestrian detection systems. In this paper, we propose a novel algorithm to reduce the number of candidate windows extracted as ROI to reduce the computation time of pedestrian detection. In our proposed method, we take advantage of the temporal correlation between the...
In this paper, we introduce a gaze classification method which classifies the locations of human gaze on a display of a mobile device. For example, when the user see the upper part of a display, our method classifies the gaze as the upper part among the available choices: upper, middle, and lower parts of the display. Our method uses appearance-based gaze estimation and gray-scale images captured...
Location estimation and navigation, especially on smartphones has shown great progress in the past decade due to its low cost and ability to work without additional infrastructure. However, a challenge is the positioning, both in terms of step detection, step length approximation as well as heading estimation, which must be accurate and robust, even when the use of the device is varied in terms of...
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