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Accurate estimation of detection/classification performance for sidescan sonar systems in Mine Counter-Measure (MCM) applications is important for informing mission tactics and adapting autonomous behaviors. The approach presented in this paper assumes that detection/classification performance can be estimated solely from historical data collected from similar surveys. This paper introduces an algorithm...
In 3D object recognition, local feature-based recognition is known to be robust against occlusion and clutter. Local feature estimation requires feature correspondences, including feature extraction and matching. Feature extraction is normally a two-stage process that estimates keypoints and keypoint descriptors, and existing studies show repeatability to be a good indicator of keypoint feature detector...
Traffic retention is an important factor of intelligent transportation system, which can vividly reflect current state of the road. Accurate estimation of traffic retention can provide support for the dynamic allocation of the traffic signal, thus alleviating the problem of urban traffic congestion. The traditional method can only estimate the long-term or red light traffic retention according to...
Frequency hopping (FH) is widely used in commercial and military communications. The purposes of FH in military communications are anti-jamming and low probability of interception. To implement low probability of detection or interception, FH signals randomly change carrier frequency. There are several kinds of FH detectors for example autocorrelation detector, maximum-likelihood detector and optimum...
In this paper, we analyze the performances of the Cell Averaging based on Lookup Tables (CA-LT) detector considering distributed targets embedded in Pareto distributed clutter. Assuming that the clutter parameters are not a priori known, the detector's structure is associated to an estimation approach that estimates the clutter parameters. The latter are used to select the suitable threshold factor...
Research efforts have been devoted to extraction and visualization of vortices in an unsteady (turbulent) flow. Characterizing the behaviors of the flow, vortices are identifiable as regions using a vortex detector known as the lambda2-criterion. Isosurface visualization renders vortex regions based on a chosen isovalue. However, it is highly challenging to choose one isovalue suitable for visualizing...
In this paper, we propose to analyze the performances of the Multiple pulse Cell Averaging based on Lookup Tables detector (M-pulse CA-LT), considering range spread targets embedded in Non Gaussian clutter. Under the assumption of Weibull clutter samples with unknown parameters, we introduce the pulse-to-pulse Moments (MOM) estimation approach. The latter estimates the shape and the scale parameter...
Big GPS data from the moving vehicles allow understanding the transportation systems in more details and at a vehicle level. While only depending on the trajectory and speed data from probe vehicles cannot estimate the traffic states (vehicle densities etc.) in real-time with the classical filtering methods, such as particular filtering (PF) and extended Kalman filtering (EKF), because the boundary...
Scientific computing requires trust in results. In high-performance computing, trust is impeded by silent data corruption (SDC), in other words corruption that remains unnoticed. Numerical integration solvers are especially sensitive to SDCs because an SDC introduced in a certain step affects all the following steps. SDCs can even cause the solver to become unstable. Adaptive solvers can change the...
Electromagnetic interference can cause severe degradation of the performance of wireless communication systems. In order to predict or handle the performance degradation, methods for calculating the impact of the interference is needed. However, for a communication system that is subjected to several impulsive interference sources, the performance is hard to calculate exactly. In addition, using standard...
In this paper, we introduce Visible Light Detection and Ranging (ViLDAR): a novel speed estimation system that utilizes visible light variation during a known time difference. The use of light emitting diodes (LED) in vehicles lighting systems has become increasingly common in the automotive industry. Concurrently, monitoring drivers’ speeds constitutes a critical issue for safety regulation agencies...
In this paper a wavelet-based transient detector is proposed for P and M class phasor measurement unit (PMU) integration. The input waveform in the sampling window is analyzed looking for the local maxima in wavelet coefficients in three different levels to detect a transient previous to the computation of the phasor. If no transients are detected in the wavelet coefficients, the signal is considered...
Pedestrian inertial navigation systems are nowadays integrated in all kind of location-based services. The orientation, particularly the heading estimation, is one of the most critical parts of the navigation system. The heading angle suffers from drift error. The algorithms proposed in the literature apply position corrections, which do not prevent the drift error to grow. We propose a novel landmark-based...
The paper presents a new method of vehicle speed estimation using image data processing. The presented method employs conversion of greyscale input images into binary form. Image conversion into binary form is based on small gradients in the input images. Contents of the obtained binary images correspond with traffic scenes presented in the input images. Vehicle speed is estimated on the basis of...
Efficient crowd counting is an essential task in crowd monitoring, and significant advances have been made in this field recently by counting-by-regression techniques. We propose in this work a learning-to-count strategy with a generic detection algorithm which benefits from a counting regressor in order to identify crowded subregions with inadequate head detection performance, and to improve their...
The problem of range-migrating target detection in a compound-Gaussian clutter is studied here. We assume a target to have a range-walk of a few range cells during the coherent processing interval, when observed by wideband radar with high range resolution. Two CFAR detectors are proposed assuming different correlation properties of clutter over range. The detectors' performance is studied via numerical...
Estimation of density and direction of crowd flow from surveillance video has attracted much research attention recently in the area of computer vision. Crowd density in a video sequence can be considered as a global entity to estimate the direction of interest of the crowd. Though there are methods to compute the density and direction, a combined approach will give more insights into the problem...
The notion of a Fast Moving Object (FMO), i.e. an object that moves over a distance exceeding its size within the exposure time, is introduced. FMOs may, and typically do, rotate with high angular speed. FMOs are very common in sports videos, but are not rare elsewhere. In a single frame, such objects are often barely visible and appear as semitransparent streaks. A method for the detection and tracking...
Target detection experiments with a novel non-parametric detector are carried out exploiting the availability of a new hyperspectral data set featuring a suburban scene with several different targets. Benefiting from its non-parametric nature and from its data adaptivity deriving from the variable-bandwidth approach, the detector is shown to provide promising results for the detection of the targets...
In this work, we consider the problem of detecting target objects in remote sensing imagery; such as detecting rooftops, trees, or cars in color/hyperspectral imagery. Many detection algorithms for this problem work by assigning a decision statistic (or “confidence”) to all, or a subset, of spatial locations in the data. A threshold is then applied to the statistics to identify detections. The detection...
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