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ABSTRACT:This paper will introduce the goals, concept and results of the project named CLOSE-SEARCH, which stands for 'Accurate and safe EGNOS-SoL Navigation for UAV-based low-cost Search-And-Rescue (SAR) operations'. The main goal is to integrate a medium-size, helicopter-type Unmanned Aerial Vehicle (UAV), a thermal imaging sensor and an EGNOS-based multi-sensor navigation system, including an Autonomous Integrity Monitoring (AIM) capability, to support search operations in difficult-to-access areas and/or night operations. The focus of the paper is three-fold. Firstly, the operational and technical challenges of the proposed approach are discussed, such as ultra-safe multi-sensor navigation system, the use of combined thermal and optical vision (infrared plus visible) for person recognition and Beyond-Line-Of-Sight communications among others. Secondly, the implementation of the integrity concept for UAV platforms is discussed herein through the AIM approach. Based on the potential of the geodetic quality analysis and on the use of the European EGNOS system as a navigation performance starting point, AIM approaches integrity from the precision standpoint; that is, the derivation of Horizontal and Vertical Protection Levels (HPLs, VPLs) from a realistic precision estimation of the position parameters is performed and compared to predefined Alert Limits (ALs). Finally, some results from the project test campaigns are described to report on particular project achievements. Together with actual Search-and-Rescue teams, the system was operated in realistic, user-chosen test scenarios. In this context, and specially focusing on the EGNOS-based UAV navigation, the AIM capability and also the RGB/thermal imaging subsystem, a summary of the results is presented.

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Recurrent monitoring of sandy beaches and of the dunes behind them is needed to improve the scientific knowledge on their dynamics as well as to develop sustainable management practices of those valuable landforms. Unmanned Aircraft Systems (UAS) are sought as a means to fulfill this need, especially leveraged by photogrammetric and LiDAR-based mapping methods and technology. The present study compares different strategies to carry UAS photogrammetric corridor mapping over linear extensions of sandy shores. In particular, we present results on the coupling of a UAS with a mobile laser scanning system, operating simultaneously in Cap Ferret, SW France. This aerial-terrestrial tandem enables terrain reconstruction with kinematic ground control points, thus largely avoiding the deployment of surveyed ground control points on the non-stable sandy ground. Results show how these three techniques-mobile laser scanning, photogrammetry based on ground control points, and photogrammetry based on kinematic ground control points-deliver accurate (i.e., root mean square errors < 15 cm) 3D reconstruction of beach-to-dune transition areas, the latter being performed at lower survey and logistic costs, and with enhanced spatial coverage capabilities. This study opens the gate for exploring longer (hundreds of kilometers) shoreline dynamics with ground-control-point-free air and ground mapping techniques.coverage [11]. Indeed, spatial coverage of airborne LiDAR is unmatched [4]. Nonetheless, it involves technological, operational and logistic costs that prevent fast acquisition of pre-and post-storm data for instance. On the other hand, UAS photogrammetric surveys [10,12] are easier to perform, and incorporating post-processed or real-time differential GNSS processing techniques (PPK/RTK) and low-cost, low-to-medium tactical grade Inertial Measurement Units (IMU) implies a reduction in the use of surveyed Ground Control Points (GCPs) [13,14]. However, concerning linear coastal landforms, GCPs remain largely necessary to mitigate accuracy degradation along the corridor, i.e., "bowl effects" [15,16]. This constraint hampers the use of UAS over hundreds of kilometers of shore, as for instance, to survey long sandy beaches after storms [17].Over the last decade, Mobile Laser Scanning (MLS) has emerged as a credible alternative for surveying coastal beaches and foredunes [18][19][20][21]. MLS mainly consist of one or several terrestrial laser scanners mounted on a moving vehicle together with a medium-to-high grade GNSS or IMU/GNSS system. Along the vehicle path, scanners collect 3D point clouds with an accuracy comparable to airborne LiDAR standards at reduced technological and logistic costs. Typical achieved point cloud densities are over 100 points per m 2 , therefore offering a valuable opportunity to study foredune growth with high resolution [20]. Yet, from a coverage standpoint, steep dune slopes create shadow areas and leave large portions of the dune top unscanned. This limitation gives rise to one of the core value proposit...

Abstract:In this article, we report about the first results of the mapKITE system, a tandem terrestrial-aerial concept for geodata acquisition and processing, obtained in corridor mapping missions. The system combines an Unmanned Aerial System (UAS) and a Terrestrial Mobile Mapping System (TMMS) operated in a singular way: real-time waypoints are computed from the TMMS platform and sent to the UAS in a follow-me scheme. This approach leads to a simultaneous acquisition of aerial-plus-ground geodata and, moreover, opens the door to an advanced post-processing approach for sensor orientation. The current contribution focuses on analysing the impact of the new, dynamic Kinematic Ground Control Points (KGCPs), which arise inherently from the mapKITE paradigm, as an alternative to conventional, costly Ground Control Points (GCPs). In the frame of a mapKITE campaign carried out in June 2016, we present results entailing sensor orientation and calibration accuracy assessment through ground check points, and precision and correlation analysis of self-calibration parameters' estimation. Conclusions indicate that the mapKITE concept eliminates the need for GCPs when using only KGCPs plus a couple of GCPs at each corridor end, achieving check point horizontal accuracy of µ E,N ≈ 1.7 px (3.4 cm) and µ h ≈ 4.3 px (8.6 cm). Since obtained from a simplified version of the system, these preliminary results are encouraging from a future perspective.

Referees are essential participants in the sport of football. They are responsible for enforcing the rules and achieving the necessary impartiality for the matches. Referees are often target of hostile reactions from fans, players, and coaches. However, few studies have focused on these experiences and the strategies they use to manage them. In order to fill this gap, a qualitative interview-based study was developed to explore the experiences of a group of football referees (four males and four females) on aggression, violence, and coping. A thematic analysis was developed combining inductive and deductive processes. Results indicated that the most frequent aggressions experienced were verbal abuse. Most of the aggressions from spectators were of a sexist nature. When aggressions were considered normal by referees, symbolic violence emerged. Racist aggressions were directed to the two Moroccan participants. Problem and emotional-focused coping strategies were identified. The two most common referee responses to coaches’ and players’ verbal abuse were penalties and send-off calls. Smiling and not considering insults as a personal matter were two emotional-focused coping strategies used toward spectator aggressions. Implications for the referees’ job and well-being as well as the quality of football competitions were highlighted to reduce aggressions and violence and to help referees to cope with hostile behaviors.

This paper addresses the key aspects of the sensor orientation and calibration approach within the mapKITE concept for corridor mapping, focusing on the contribution analysis of point-and-scale measurements of kinematic ground control points. MapKITE is a new mobile, simultaneous terrestrial and aerial, geodata acquisition and post-processing method. On one hand, the acquisition system is a tandem composed of a terrestrial mobile mapping system and an unmanned aerial system, the latter equipped with a remote sensing payload, and linked through a 'virtual tether', that is, a real-time waypoint supply from the terrestrial vehicle to the unmanned aircraft. On the other hand, mapKITE entails a method for geodata post-processing (specifically, sensor orientation and calibration) based on the described acquisition paradigm, focusing on few key aspects: the particular geometric relationship of a mapKITE network &ndash; the aerial vehicle always observes the terrestrial one as they both move &ndash;, precise air and ground trajectory determination &ndash; the terrestrial vehicle is regarded as a kinematic ground control point &ndash; and new photogrammetric measurements &ndash; pointing on and measuring the scale of an optical target on the roof of the terrestrial vehicle &ndash; are exploited. <br><br> In this paper, we analyze the performance of aerial image orientation and calibration in mapKITE for corridor mapping, which is the natural application niche of mapKITE, based on the principles and procedures of integrated sensor orientation with the addition of point-and-scale photogrammetric measurements of the kinematic ground control points. To do so, traditional (static ground control points, photogrammetric tie points, aerial control) and new (pointing-and-scaling of kinematic ground control points) measurements have been simulated for mapKITE corridor mapping missions, consisting on takeoff and calibration pattern, single-pass corridor operation potentially performing calibration patterns, and landing and calibration pattern. Our preliminary results show that the exterior orientation, interior orientation and tie points precision estimates are better when using kinematic control with few static ground control, and even with excluding the latter. We conclude then that mapKITE can be a breakthrough on the UAS-based corridor mapping field, as precision requirements can be achieved for single-pass operation with no need for traditional static ground control points.

In deaths with forensic intervention, the official statistical documents do not correctly report external causes of death, and statistics for natural causes of death approach acceptable levels of accuracy. The results are mainly due to deficits in reporting and certifying these causes in the official statistics.