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Aujourd'hui, j'ai rendez-vous A 12 h avecM. Denis Delaville, PDG de DiaSorinFrance.La societe est implantee dans le parctechnologique d'Antony. Quelques pho-tos... et je sonne a ('entree. Immediate-ment accueilli, j'entre et suis ...
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Aujourd'hui, j'ai rendez-vous A 12 h avecM. Denis Delaville, PDG de DiaSorinFrance.La societe est implantee dans le parctechnologique d'Antony. Quelques pho-tos... et je sonne a ('entree. Immediate-ment accueilli, j'entre et suis l'hotessevers le bureau du PDG ou je suis attendu.Grand et mince, les joues parcouruesd'une ombre virile, Denis Delaville, cour-tois et souriant me propose un siege. Pas de phase d'observation... nousouvrons le debat.
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This article proposes an inertial navigation algorithm intended to lower the negative consequences of the absence of GNSS (Global Navigation Satellite System) signals on the navigation of autonomous fixed wing low SWaP (Size, Weig...
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This article proposes an inertial navigation algorithm intended to lower the negative consequences of the absence of GNSS (Global Navigation Satellite System) signals on the navigation of autonomous fixed wing low SWaP (Size, Weight, and Power) UAVs (Unmanned Air Vehicles). In addition to accelerometers and gyroscopes, the filter takes advantage of sensors usually present onboard these platforms, such as magnetometers, Pitot tube, and air vanes, and aims to reduce the attitude error and position drift (both horizontal and vertical) with the dual objective of improving the aircraft GNSS-Denied inertial navigation capabilities as well as facilitating the fusion of the inertial filter with visual odometry algorithms. Stochastic high fidelity Monte Carlo simulations of two representative scenarios involving the loss of GNSS signals are employed to evaluate the results, compare the proposed filter with more traditional implementations, and analyze the sensitivity of the results to the quality of the onboard sensors. The author releases the C++ implementation of both the navigation filter and the high fidelity simulation as open-source software [1]. (C) 2021 The Authors. Published by Elsevier Masson SAS.
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The remarks made by Lacelle (2010), specifically those about the interpretation of the δ~(18)O in needle fibre calcite (NFC), are interesting and we agree with most of his general statements; but the trees must not hide the fores...
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The remarks made by Lacelle (2010), specifically those about the interpretation of the δ~(18)O in needle fibre calcite (NFC), are interesting and we agree with most of his general statements; but the trees must not hide the forest. The significance of the δ~(18)O data is minor compared to the study of the mineralogy and crystallography of the various types of NFCs. Lacelle (2010) uses the general term NFC for all of the various crystal habits, whereas we demonstrated that there are different types of NFCs originating from various processes, including possible evaporation, and possibly from different parent solutions (early diagenesis).
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We study the basic structures of matrix-valued harmonic functions on locally compact groups. We show that the bounded matrix-valued harmonic functions on a group form a Jordan triple system and we determine its structure. We also ...
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We study the basic structures of matrix-valued harmonic functions on locally compact groups. We show that the bounded matrix-valued harmonic functions on a group form a Jordan triple system and we determine its structure. We also show that Liouville property implies amenability of the group. We characterize the unbounded matrix-valued harmonic functions on abelian groups. [References: 44]
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For vehicles to operate in unmapped areas with some degree of autonomy, it would be useful to aggregate and store processed sensor data so that it can be used later. In this paper, a tool that records and optimizes the placement o...
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For vehicles to operate in unmapped areas with some degree of autonomy, it would be useful to aggregate and store processed sensor data so that it can be used later. In this paper, a tool that records and optimizes the placement of costmap data on a persistent map is presented. The optimization takes several factors into account, including local vehicle odometry, GPS signals when available, local map consistency, deformation of map regions, and proprioceptive GPS offset error. Results illustrating the creation of maps from previously unseen regions (a 100 m × 880 m test track and a 1.2 km dirt trail) are presented, with and without GPS signals available during the creation of the maps. Finally, two examples of the use of these maps are given. First, a path is planned along roads that have been seen exactly once during the mapping phase. Secondly, the map is used for vehicle localization in the absence of GPS signals.
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To characterize the water quality of an aquatic ecosystem, a lot of importance is given both to the qualitative and quantitative structure of the biocenoses that populate the ecosystem. Oligotrophic lakes with low trophicity are a...
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To characterize the water quality of an aquatic ecosystem, a lot of importance is given both to the qualitative and quantitative structure of the biocenoses that populate the ecosystem. Oligotrophic lakes with low trophicity are also the most sustainable in time. The eutrophic lakes contain in dissolved state a large amount of nutrients, which causes an intense dynamic of their respective biocoenosis. Regarding Vadeni lake from biological point of view only qualitative analyzes were carried out in order to establish associations of bodies that populate the water mass (plankton) and the benthos of the lake shores. By comparing the values obtained for the analyzed indicators with the values proposed by the regulations in force, V?deni lake can be classified as oligotrophic.
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In this paper, we propose a UAV path planner travelling from a given source to goal location in GPS-denied areas. The environment consists of a set of cellular towers which are treated as landmarks having finite communication rang...
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In this paper, we propose a UAV path planner travelling from a given source to goal location in GPS-denied areas. The environment consists of a set of cellular towers which are treated as landmarks having finite communication range. The vehicle has to perform dead reckoning in regions where landmarks are not available. Therefore, the objective is to determine a time optimal path taking the presence of landmarks into account while ensuring the covariance due to dead-reckoning is within a given bound. Solving the stochastic optimal control problem to determine a path in the continuous domain is very difficult and hence we discrete the path as a set of way points and optimize the location of these way points to obtain a time optimal path satisfying the covariance bounds. We use a particle swarm optimization technique coupled with a rabbit-carrot based path following technique to determine a near-optimal path. Numerical results are presented to show that our approach produces feasible paths that are near-optimal and satisfy the covariance bounds.
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Mutation of the Wilms tumor gene (WT1) is associated with two well-described syndromes called Denys-Drash (DDS) and Frasier (FS). Both are associated with nephropathy and ambiguous genitalia and have overlapping clinical and molec...
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Mutation of the Wilms tumor gene (WT1) is associated with two well-described syndromes called Denys-Drash (DDS) and Frasier (FS). Both are associated with nephropathy and ambiguous genitalia and have overlapping clinical and molecular features. The known risk of Wilms tumor in DDS and gonadoblastoma (GB) in FS patients requires tumor surveillance. The literature reports the occurrence of GB in DDS as lower than FS. This case highlights a very early presentation of bilateral GB in DDS and the consideration of early prophylactic gonadectomy at the time of diagnosis with DDS.
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Cloud Computing and Cloud Platforms have become an essential resource for businesses, due to their advanced capabilities, performance, and functionalities. Data redundancy, scalability, and security, are among the key features off...
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Cloud Computing and Cloud Platforms have become an essential resource for businesses, due to their advanced capabilities, performance, and functionalities. Data redundancy, scalability, and security, are among the key features offered by cloud platforms. Location-Based Services (LBS) often exploit cloud platforms to host positioning and localisation systems. This paper introduces a systematic review of current positioning platforms for GNSS-denied scenarios. We have undertaken a comprehensive analysis of each component of the positioning and localisation systems, including techniques, protocols, standards, and cloud services used in the state-of-the-art deployments. Furthermore, this paper identifies the limitations of existing solutions, outlining shortcomings in areas that are rarely subjected to scrutiny in existing reviews of indoor positioning, such as computing paradigms, privacy, and fault tolerance. We then examine contributions in the areas of efficient computation, interoperability, positioning, and localisation. Finally, we provide a brief discussion concerning the challenges for cloud platforms based on GNSS-denied scenarios.
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