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In this paper, we propose a centralized electric vehicles (EVs) recharge scheduling system for parking lots using a realistic vehicular mobility/parking pattern focusing on individual parking lots. We consider two different types of EV based on their mobility/parking patterns: 1) regular EVs; and 2) irregular EVs. An extensive trace-based vehicular mobility model collected from the Canton of Zurich...
In this paper, we propose a car positioning approach that does not rely on GPS. We propose to use car wheel speeds and road maps in order to achieve robust positioning of the vehicle. The vehicle positioning is achieved by applying particle filtering on a graph-based representation of a road map. We show that the vehicle positioning is feasible and robust with these two inputs at a really low computational...
In this paper, we present a car self-localization approach based on free inputs. We propose to use wheel speeds, which is available on most car through the CAN bus, and community developed road maps. A particle filter framework is used to achieve self-localization on a graph-based representation of a road map. Our results suggests that self-localization and tracking are feasible with these two inputs...
Motorbikes are often difficult to detect in overhead road traffic images due to the variability of color, size, shape as well as trajectories. This paper tackles the problem of robust and real time image segmentation for motorbike counting. First of all, we perform background subtraction. Foreground blobs are then refined with Laplacian densities. This fusion enables to achieve a significant robustness...
This paper introduces a new framework to improve the performance of Viola and Jones face detector on omnidirectional unwrapped images. First, an optimization scheme is used to improve the unwrapped image specifically for rectangular Haar-like features. Then, we compare our unwrapping approach to the performance obtained with spherical unwrapping. The impact of the decision boundary and candidate window...
In this paper, we tackle the problem of map estimation from small set of vehicular GPS traces collected from low cost devices. Contrary to the existing works, we rely only on GPS information. First, we propose a fast implementation of Kalman filtering of spline-based road modeling. Our approach demonstrates a significant boost of the computation speed while maintained a good estimation error. Secondly,...
This article studies the feasibility of an exteroceptive system for the contactless control of a motion-compensated gangway which can be used for maintenance operations on offshore wind farms. Our study shows that current systems based only on inertial systems are not accurate enough to ensure the gangway is held in place without being secured mechanically. Using measurements from a 2D LIDAR system,...
We present an algorithm for reconstruction of piece-wise planar scenes from only two views and based on minimum line correspondences. We first recover camera rotation by matching vanishing points based on the methods already exist in the literature and then recover the camera translation by searching among a family of hypothesized planes passing through one line. Unlike algorithms based on line segments,...
The task of recovering the camera motion relative to the environment (motion estimation) is fundamental to many computer vision applications. We present an algorithm for reconstruction of piece-wise planar scenes from only two views and based on minimum line correspondences. We first recover camera rotation by matching vanishing points based on the methods already exist in the literature and then...
Whereas some methods for plane extraction have been proposed, this problem still remains an open issue due to the complexity of the task. This paper especially focuses on the extraction of points lying on a plane (such as the ground and buildings walls) in sequences acquired by a central omnidirectional camera. Our approach is based on the epipolar constraint for planar scenes (i.e. homography) on...
Altitude is one of the most important parameters to be known for an Unmanned Aerial Vehicle (UAV) especially during critical maneuvers such as landing or steady flight. In this paper, we present mixed stereoscopic vision system made of a fish-eye camera and a perspective camera for altitude estimation. Contrary to classical stereoscopic systems based on feature matching, we propose a plane sweeping...
In this paper, a performance evaluation of the Routing Protocol for Low power and Lossy Networks (RPL) in a typical outdoor Smart Grid Substation Network is presented. Detailed simulations are carried out to produce several routing performance metrics using real-life scenarios. The real outdoor network was reproduced in simulation with the help of topology and link quality data gathered from the network...
In this paper, a performance evaluation of the Routing Protocol for Low power and Lossy Networks (RPL) is presented. Detailed simulations are carried out to produce several routing performance metrics using a set of real-life scenarios. A real outdoor network was reproduced in simulation with the help of topology and link quality data. Behaviors of such a network in presence of RPL, their reason and...
Due to distorsions of catadioptric sensors, omnidirectional images can not be treated as classical images. If the equivalence between central catadioptric images and spherical images is now well known and used, spherical analysis often leads to complex methods particularly tricky to employ. In this paper, we propose to derive omnidirectional image treatments by using geodesic metric. We demonstrate...
Unmanned Aerial Vehicles (UAV) are the subject of an increasing interest in many applications and a key requirement for autonomous navigation is the attitude/position stabilization of the vehicle. Some previous works have suggested using catadioptric vision, instead of traditional perspective cameras, in order to gather much more information from the environment and therefore improve the robustness...
Path computation elements (PCE's) are used to compute end-to-end paths across multiple areas. Multiple PCE's may be dedicated to each area to provide sufficient path computation capacity and redundancy. An open problem is to which PCE to send the path computation request. This problem may be a non trivial problem if PCE's have uneven processing capacities. This paper presents a queueing model based...
This paper reports an analytical and numerical study of natural convection in a horizontal binary fluid layer confined between two horizontal porous walls. The cavity is heated from the bottom by a constant heat flux while the long side walls are impermeable and adiabatic. The Beavers-Joseph slip condition on velocity is applied at the interface between the fluid and porous layers. Both double-diffusive...
Most of vision-based algorithms for motion and localization estimation requires matching some interest points in a pair of images. After building feature correspondence, it is possible to estimate camera motion/localization using epipolar geometry. However feature matching is still a challenging problem because of time constraint or image variability for example. In several robotic applications, the...
A key requirement for unmanned aerial vehicles (UAV) applications is the attitude stabilization of the aircraft, which requires the knowledge of its orientation. It is now well established that traditional navigation equipments, like GPS or INS, suffer from several disadvantages. That is why some works have suggested a vision-based approach of the problem. Especially, catadioptric vision is more and...
Camera calibration is an important step for vision-based stabilization of unmanned aerial vehicles (UAV). The goal of this paper is to develop a method for automatic calibration of a catadioptric camera so that it can be easily run before mounting the camera on the UAV or even during the flight to deal with vibrations or shocks. Whereas existing works can provide interesting results, they suffer from...
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