820 research outputs found

    Fast and Robust Detection of Fallen People from a Mobile Robot

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    This paper deals with the problem of detecting fallen people lying on the floor by means of a mobile robot equipped with a 3D depth sensor. In the proposed algorithm, inspired by semantic segmentation techniques, the 3D scene is over-segmented into small patches. Fallen people are then detected by means of two SVM classifiers: the first one labels each patch, while the second one captures the spatial relations between them. This novel approach showed to be robust and fast. Indeed, thanks to the use of small patches, fallen people in real cluttered scenes with objects side by side are correctly detected. Moreover, the algorithm can be executed on a mobile robot fitted with a standard laptop making it possible to exploit the 2D environmental map built by the robot and the multiple points of view obtained during the robot navigation. Additionally, this algorithm is robust to illumination changes since it does not rely on RGB data but on depth data. All the methods have been thoroughly validated on the IASLAB-RGBD Fallen Person Dataset, which is published online as a further contribution. It consists of several static and dynamic sequences with 15 different people and 2 different environments

    Promoting physical activity among university students: a systematic review of controlled trials

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    Objective: University study is often accompanied by a decline in physical activity (PA) levels but can offer the opportunity to promote a lifelong active lifestyle. This review aims to summarize controlled trials of interventions promoting PA among uni- versity students, describing the quality of the evidence, effective strategies, and deficiencies in the interventions employed, to provide directions for future research and for practical implementations. Data Source: PubMed, PsychINFO, Cochrane Library, Education Source, and SPORTDiscus. Study Inclusion Criteria: Randomized or nonrandomized controlled trial, describing an intervention to promote PA in uni- versity students, where PA was one of the outcomes and results were published in English. Data Extraction: Country, study design, participants\u2019 inclusion criteria, participation rate and characteristics, randomization, blinding, theoretical framework, intervention characteristics, participant retention rate and withdrawal reasons, measures employed, data analysis, PA results, and findings regarding PA correlates. Data Synthesis: Data were synthetized considering study characteristics, strategies used, and outcomes. Results: Two thousand five hundred eighty-five articles were identified. Twenty-seven studies met the inclusion criteria. Sixteen studies reported an increase in PA levels. Conclusion: Physical Activity promotion interventions should address a range of behavioral determinants. Personalized approaches and PA sessions should be considered in future studies. The high risk of bias of many studies (mainly due to attrition and poor reporting) and missing information about intervention components limit the strength of conclusions about the most effective strategies and the evidence of effectiveness, highlighting the need for further high-quality studies

    Multicolor Photometry of the Uranus Irregular Satellites Sycorax and Caliban

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    We report on accurate BVRI photometry for the two Uranus irregular satellites Sycorax and Caliban. We derive colours, showing that Sycorax is bluer than Caliban. Our data allows us to detect a significant variability in the Caliban's light-curve, which suggests an estimated period of about 3 hours. Despite it is the brighter of the two bodies, Sycorax does not display a strong statistically significant variability. However our data seem to suggest a period of about 4 hoursComment: 17 pages, 2 eps figures, in press in Astronomical Journa

    Real-time marker-less multi-person 3D pose estimation in RGB-Depth camera networks

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    This paper proposes a novel system to estimate and track the 3D poses of multiple persons in calibrated RGB-Depth camera networks. The multi-view 3D pose of each person is computed by a central node which receives the single-view outcomes from each camera of the network. Each single-view outcome is computed by using a CNN for 2D pose estimation and extending the resulting skeletons to 3D by means of the sensor depth. The proposed system is marker-less, multi-person, independent of background and does not make any assumption on people appearance and initial pose. The system provides real-time outcomes, thus being perfectly suited for applications requiring user interaction. Experimental results show the effectiveness of this work with respect to a baseline multi-view approach in different scenarios. To foster research and applications based on this work, we released the source code in OpenPTrack, an open source project for RGB-D people tracking.Comment: Submitted to the 2018 IEEE International Conference on Robotics and Automatio

    People tracking and re-identification by face recognition for RGB-D camera networks

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    This paper describes a face recognition-based people tracking and re-identification system for RGB-D camera networks. The system tracks people and learns their faces online to keep track of their identities even if they move out from the camera's field of view once. For robust people re-identification, the system exploits the combination of a deep neural network- based face representation and a Bayesian inference-based face classification method. The system also provides a predefined people identification capability: it associates the online learned faces with predefined people face images and names to know the people's whereabouts, thus, allowing a rich human-system interaction. Through experiments, we validate the re-identification and the predefined people identification capabilities of the system and show an example of the integration of the system with a mobile robot. The overall system is built as a Robot Operating System (ROS) module. As a result, it simplifies the integration with the many existing robotic systems and algorithms which use such middleware. The code of this work has been released as open-source in order to provide a baseline for the future publications in this field

    Lateglacial and Holocene vegetation history in the Insubrian Southern Alps—New indications from a small-scale site

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    Fundamental uncertainties exist in the study region about the former lowland vegetation at local scales. All existing palaeoecological results are derived from sediments of medium- to large-sized sites (8-5000ha), which are thought to record mainly regional vegetation in their pollen content. Therefore the very small mire at Balladrum (0.05ha) was analysed for pollen, plant-macrofossils, and charcoal and the results compared with those of previous studies in the same region. Common regional signals were detected, but also new insights for the tree species Pinus cembra (L.), Abies alba (Mill.) and Castanea sativa (Mill.). Our palaeobotanical data reveal the local dominance of the timberline species P. cembra during the Lateglacial (16500-14250 cal b.p.) at low-altitudes. For A. alba an early presence in the area is suggested by pollen data, corroborating previous high-altitudinal studies indicating the presence of glacial refugia in the region. Occasional findings of C. sativa pollen throughout the Holocene may indicate the local but very rare presence of this species in the Insubrian Southern Alps, in contrast to the conventional opinion that C. sativa was introduced during the Roman Period. Altogether the results confirm the need of multiproxy palaeobotanical records from basins of variable size to assess the past composition of vegetation more accuratel

    RUR53: an Unmanned Ground Vehicle for Navigation, Recognition and Manipulation

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    This paper proposes RUR53: an Unmanned Ground Vehicle able to autonomously navigate through, identify, and reach areas of interest; and there recognize, localize, and manipulate work tools to perform complex manipulation tasks. The proposed contribution includes a modular software architecture where each module solves specific sub-tasks and that can be easily enlarged to satisfy new requirements. Included indoor and outdoor tests demonstrate the capability of the proposed system to autonomously detect a target object (a panel) and precisely dock in front of it while avoiding obstacles. They show it can autonomously recognize and manipulate target work tools (i.e., wrenches and valve stems) to accomplish complex tasks (i.e., use a wrench to rotate a valve stem). A specific case study is described where the proposed modular architecture lets easy switch to a semi-teleoperated mode. The paper exhaustively describes description of both the hardware and software setup of RUR53, its performance when tests at the 2017 Mohamed Bin Zayed International Robotics Challenge, and the lessons we learned when participating at this competition, where we ranked third in the Gran Challenge in collaboration with the Czech Technical University in Prague, the University of Pennsylvania, and the University of Lincoln (UK).Comment: This article has been accepted for publication in Advanced Robotics, published by Taylor & Franci

    Smile aesthetics: an interdisciplinary approach

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    The face is the visiting card of our person to society and the smile is its most important characterization: the presence of anomalies may represent a break in harmony and facial aesthetics. The main objective of this writing is to identify the main characteristics of a pleasant smile and to analyse some of the available therapeutic approaches aiming to correct dentofacial anomalies. A bibliographic search was performed using B-on, PubMed and textbooks, based on the keywords “smile aesthetics”. According to the literature analysed, it seems that following certain guidelines and parameters is crucial in achieving the best possible outcome and the clinician should consider an interdisciplinary therapeutic approach, within the limits of anatomy and function.O rosto é o cartão de visitas de uma pessoa para a sociedade e o sorriso é a sua caracterização mais importante: a presença de anomalias pode representar uma ruptura na harmonia e na estética facial. O objetivo principal deste trabalho é identificar as principais características de um sorriso agradável e analisar algumas das abordagens terapêuticas disponíveis, visando corrigir as anomalias dentofaciais. Foi realizada uma pesquisa bibliográfica utilizando B-on, PubMed e livros didáticos, com base na palavra-chave "sorriso estético". De acordo com a literatura analisada, parece que seguir certas diretrizes e parâmetros seja crucial para alcançar o melhor resultado possível e o clínico deveria considerar uma abordagem terapêutica interdisciplinar, dentro dos limites da anatomia e da função

    Smile aesthetics: an interdisciplinary approach

    Get PDF
    The face is the visiting card of our person to society and the smile is its most important characterization: the presence of anomalies may represent a break in harmony and facial aesthetics. The main objective of this writing is to identify the main characteristics of a pleasant smile and to analyse some of the available therapeutic approaches aiming to correct dentofacial anomalies. A bibliographic search was performed using B-on, PubMed and textbooks, based on the keywords “smile aesthetics”. According to the literature analysed, it seems that following certain guidelines and parameters is crucial in achieving the best possible outcome and the clinician should consider an interdisciplinary therapeutic approach, within the limits of anatomy and function.O rosto é o cartão de visitas de uma pessoa para a sociedade e o sorriso é a sua caracterização mais importante: a presença de anomalias pode representar uma ruptura na harmonia e na estética facial. O objetivo principal deste trabalho é identificar as principais características de um sorriso agradável e analisar algumas das abordagens terapêuticas disponíveis, visando corrigir as anomalias dentofaciais. Foi realizada uma pesquisa bibliográfica utilizando B-on, PubMed e livros didáticos, com base na palavra-chave "sorriso estético". De acordo com a literatura analisada, parece que seguir certas diretrizes e parâmetros seja crucial para alcançar o melhor resultado possível e o clínico deveria considerar uma abordagem terapêutica interdisciplinar, dentro dos limites da anatomia e da função
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