10 research outputs found

    VGI Edit History Reveals Data Trustworthiness and User Reputation

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    Ponencias, comunicaciones y pĂłsters presentados en el 17th AGILE Conference on Geographic Information Science "Connecting a Digital Europe through Location and Place", celebrado en la Universitat Jaume I del 3 al 6 de junio de 2014.Volunteered Geographic Information (VGI) is an approach to crowdsource information about geospatial features around us. People around the world are engaged with typing in their observations about the world (like locations of shops, cafeterias), or to semi-automatically gather them with mobile devices (like hiking paths or roads). In this process people might make mistakes, for instance assign misleading tags to features or provide over simplistic boundaries for features. In this paper we study what kinds of things might contribute to assess trustworthiness of data, and reputation of contributors for VGI. We present a model for analysing the different factors, and a method for automatically creating the trust and reputation scores

    Data trustworthiness and user reputation as indicators of VGI quality

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    ABSTRACTVolunteered geographic information (VGI) has entered a phase where there are both a substantial amount of crowdsourced information available and a big interest in using it by organizations. But the issue of deciding the quality of VGI without resorting to a comparison with authoritative data remains an open challenge. This article first formulates the problem of quality assessment of VGI data. Then presents a model to measure trustworthiness of information and reputation of contributors by analyzing geometric, qualitative, and semantic aspects of edits over time. An implementation of the model is running on a small data-set for a preliminary empirical validation. The results indicate that the computed trustworthiness provides a valid approximation of VGI quality

    Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study

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    Background: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak. Methods: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study. Results: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM. Conclusion: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide

    Status of the Virgo project

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    We describe the present state and future evolution of the Virgo gravitational wave detector, realized by theVirgo Collaboration at the European Gravitational Observatory, in Cascina near Pisa in Italy. We summarize basic principles of the operation and the design features of the Virgo detector. We present the sensitivity evolution due to a series of intermediate upgrades called Virgo+ which is being completed this year and includes new monolithic suspensions. We describe the present scientific potential of the detector. Finally we discuss the plans for the second generation of the detector, called Advanced Virgo, introducing its newfeatures, the expected sensitivity evolution and the scientific potential

    Advanced Virgo: a second-generation interferometric gravitational wave detector

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    Advanced Virgo is the project to upgrade the Virgo interferometric detector of gravitational waves, with the aim of increasing the number of observable galaxies (and thus the detection rate) by three orders of magnitude. The project is now in an advanced construction phase and the assembly and integration will be completed by the end of 2015. Advanced Virgo will be part of a network, alongside the two Advanced LIGO detectors in the US and GEO HF in Germany, with the goal of contributing to the early detection of gravitational waves and to opening a new window of observation on the universe. In this paper we describe the main features of the Advanced Virgo detector and outline the status of the construction

    Estimating transient detection efficiency in electromagnetic follow up searches

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    During the most recent LIGO-Virgo science run (Dec 17 2009 to Jan 8 2010 and Sep 2 to Oct 20 2010) multi-messenger searches were performed using several partner telescopes. This resulted in large data sets with images covering several square degrees of the sky. Analysis of these images is currently underway using a variety of different tools. We present an overview of these efforts, in particular the development of new tools which enable us to establish the efficiency for transient images in the fields. This is critical in establishing the sensitivity of gravitational wave and electromagnetic multi-messenger searches to the astrophysical signals we expect to be associated with gravitational waves

    Recent results for the search of continuous waves with the LIGO and Virgo detectors

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    The 'First Generation Era' of gravitational wave detectors is now over, but the data analysis effort for the search of continuous gravitational waves is still ongoing and active. Many results have been produced but still many searches are underway. I present and discuss here the most recent results for this search, together with short discussions on analysis which are now underway and plans for the near future. The discussion on long-term plans and perspectives for the so-called Advanced Detector Era are beyond the scope of this paper

    The Analysis of ROTSE Images of Potential Counterparts to Gravitational Wave Events

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    During the most recent LIGO-GEO-Virgo science run a number of partner telescopes performed follow-up observations of gravitational wave (GW) candidates. One of these collaborators was the ROTSE project. Consisting of four optical telescopes, ROTSE responded to GW triggers and took over 700 follow-up images. Analysis of these images is currently under way using ROTSE's own image processing pipeline. We describe the analysis used to search for transients of astrophysical significance, and steps being taken to automate and optimise the analysis for rapid identification of electromagnetic (EM) counterparts to GW candidates

    Recent searches for gravitational-wave bursts associated with magnetar flares with LIGO, GEO, and Virgo

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    Energetic electromagnetic flares from magnetars - highly magnetized neutron stars - are associated with sudden rearrangements of the mechanical and/or magnetic configurations of the star, which can give rise to mechanical oscillations, some of which may be strong radiators of gravitational waves. General arguments have indicated that gravitational-wave bursts associated temporally with (giant) flares from galactic magnetars may be observable with ground-based gravitational wave detectors. After discussing the expectations based on the astrophysical models, we present results from several campaigns to search for such bursts using the first generation of LIGO, GEO, and Virgo detectors over the period 2005-2009, emphasizing the most recent results. No detections have been made, and we present astrophysically informed limits. Finally, we discuss prospects for progress
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