219 research outputs found
Design, implementation and experiment of a YeSQL Web Crawler
We describe a novel, "focusable", scalable, distributed web crawler based on
GNU/Linux and PostgreSQL that we designed to be easily extendible and which we
have released under a GNU public licence. We also report a first use case
related to an analysis of Twitter's streams about the french 2012 presidential
elections and the URL's it contains
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Framing COVID-19: Analysing the Effect of Framing on the Popular Understanding of the Coronavirus Pandemic
Traditionally, in times of crises, leaders and governments resort to appeals of national defence and security to rally a population together, to create a united front against that crisis. Issues of main concern are framed through a militaristic and security lens to sensationalise the issue, to make compliance of the population easier, and to give the government the necessary powers to address the issue. Simultaneously, less important issues tend to be framed through a socio-economic lens. Such a lens garners less interest in the issue, and thus less action.
This thesis looks at the framing of the coronavirus pandemic in 5 countries through a comparative lens, to assess how much of a security frame countries used. A framing index is constructed to measure the level of security framing, looking for elements of speech and actions from governments. Framing is then measured against compliance, trust in government, and coronavirus performance. Findings suggest that government framing had no impact on how regular people viewed or understood the pandemic. However, framing reflected how the government itself viewed the pandemic and the possible solutions for it. Countries that employed a more security frame had considerably worse health outcomes
Classification des utilisateurs de Twitter en fonction de leurs comportements Ă l'aide d'un algorithme des K-means
International audienceDans cette présentation, nous proposons une analyse des comportements des utilisateurs de Twitter durant la campagne des élections européennes de 2014 dans le but de former des groupes d'utilisateurs qui avaient tendance à faire des actions aux mêmes moments durant cette campagne. Pour ce faire, nous effectuons une classification des jours de la campagne électorale puis, à l'aide de la classification obtenue, nous proposons une classification des utilisateurs dans le but d'étudier leurs comportements. Cette classification imbriquée nous oblige à transformer le modèle pour permettre une exécution plus rapide de l'algorithme des K-means. Nous concluons cette présentation par une analyse des résultats obtenus
Analyse des comportements des utilisateurs de Twitter durant la campagne des élections européennes de 2014
International audienceIn this talk, we provide an analysis of the behavior of Twitter users during the 2014 European elections campaign. Our goal is forming user groups that tended to do the same action at the same time during this campaign. We propose a classification of the days of the electoral campaign and, using the classification obtained, we propose a classification of the users in order to study their behaviors. We conclude this talk with an analysis of the results obtained.Dans cette présentation, nous proposons une analyse des comportements des utilisateurs de Twitter durant la campagne des élections européennes de 2014 dans le but de former des groupes d'utilisateurs qui avaient tendance à faire des actions aux mêmes moments durant cette campagne. Pour ce faire, nous effectuons une classification des jours de la campagne électorale puis, à l'aide de la classification obtenue, nous proposons une classification des utilisateurs dans le but d'étudier leurs comportements. Nous concluons cette présentation par une analyse des résultats obtenus
Rethinking business models for innovation
One of the major challenges confronted by those in charge of technological innovation involves anticipating the value creation model sufficiently early on,in a highly uncertain context both as far as the technology itself is concerned and the potential market. Today, in many industrial sectors, the innovation boundaries have moved towards projects that are more and more exploratory and fuzzy. The simple optimisation of linear processes of the "stage-gate" type is no longer sufficient to build sustainable competitive advantages. The notion of Business Models, when applied to innovation, enables us to describe how a company creates value through innovation, generally within a business ecosystem, and how the value will be distributed between the actors involved. The authors of this book believe that the notions of Business Modelling and value creation are key to all the dimensions of successful innovation, whether technology, marketing, organisational or economically based. Rethinking Business Models for Innovation: this title describes the relationship between thinking, modelling, and also field-testing. The book is based on a series of nine recent cases of innovation involving company managers, often assisted by researchers (the co-authors of each chapter), and how they built and formalised their Business Models and then tested their strategies. After having discovered the variety of the cases, the reader will understand that every innovation situation generates specific questions about Business Models. However, we feel that we can identify three key issues that arise, more or less, in each of these projects. The chapters in this book build on these issues: the identification of sources of value and revenue models (the notion of value creation), the position of the company in the value-network or ecosystem (the sharing of value) and finally the evolution of Business MoDdels over time (the sustainability and the competitiveness of the company). The last chapter goes over all the contributions, exploring the notion of value in the Business Model approach.business model ; innovation ; value ; entrepreneurial project
: Lessons from entrepreneurial projects
International audienceOne of the major challenges confronted by those in charge of technological innovation involves anticipating the value creation model sufficiently early on,in a highly uncertain context both as far as the technology itself is concerned and the potential market. Today, in many industrial sectors, the innovation boundaries have moved towards projects that are more and more exploratory and fuzzy. The simple optimisation of linear processes of the "stage-gate" type is no longer sufficient to build sustainable competitive advantages. The notion of Business Models, when applied to innovation, enables us to describe how a company creates value through innovation, generally within a business ecosystem, and how the value will be distributed between the actors involved. The authors of this book believe that the notions of Business Modelling and value creation are key to all the dimensions of successful innovation, whether technology, marketing, organisational or economically based. Rethinking Business Models for Innovation: this title describes the relationship between thinking, modelling, and also field-testing. The book is based on a series of nine recent cases of innovation involving company managers, often assisted by researchers (the co-authors of each chapter), and how they built and formalised their Business Models and then tested their strategies. After having discovered the variety of the cases, the reader will understand that every innovation situation generates specific questions about Business Models. However, we feel that we can identify three key issues that arise, more or less, in each of these projects. The chapters in this book build on these issues: the identification of sources of value and revenue models (the notion of value creation), the position of the company in the value-network or ecosystem (the sharing of value) and finally the evolution of Business MoDdels over time (the sustainability and the competitiveness of the company). The last chapter goes over all the contributions, exploring the notion of value in the Business Model approach.L'innovation technologique, qu'elle soit conduite par des start-ups ou par de grandes entreprises, n'est plus une condition suffisante de la création de valeur. Créer de la valeur sur des marchés nouveaux nécessite le plus souvent de repenser l'organisation de l'entreprise, sa façon de faire des affaires, ses partenariats stratégiques, autrement dit, son business model. Cet ouvrage se veut un guide pour les porteurs de projets d'innovation en leur fournissant des outils de compréhension et d'analyse de la dimension stratégique de leur projet. Les études de cas présentées sont le fruit d'une collaboration étroite entre les porteurs de chacun des projets et des chercheurs en management de l'innovation reconnus. Au travers de ces cas, trois grandes problématiques sont abordées : l'identification des sources de valeur chez les clients potentiels, la position que l'entreprise pourra prendre dans son écosystème et enfin l'évolution des business models dans le temps. Sur chacun des cas, le lecteur aura accès à une compréhension fine des problèmes stratégiques posés par l'innovation ainsi que des outils de management mis en œuvre pour aider à réfléchir et à agir. (http://www.rethinkingbusinessmodel.net/
Unveiling the optimal regression model for source apportionment of the oxidative potential of PM<sub>10</sub>
The capacity of particulate matter (PM) to generate reactive oxygen species (ROS) in vivo leading to oxidative stress is thought to be a main pathway in the health effects of PM inhalation. Exogenous ROS from PM can be assessed by acellular oxidative potential (OP) measurements as a proxy of the induction of oxidative stress in the lungs. Here, we investigate the importance of OP apportionment methods for OP distribution by PM10 sources in different types of environments. PM10 sources derived from receptor models (e.g., EPA positive matrix factorization (EPA PMF)) are coupled with regression models expressing the associations between PM10 sources and PM10 OP measured by ascorbic acid (OPAA) and dithiothreitol assay (OPDTT). These relationships are compared for eight regression techniques: ordinary least squares, weighted least squares, positive least squares, Ridge, Lasso, generalized linear model, random forest, and multilayer perceptron. The models are evaluated on 1Â year of PM10 samples and chemical analyses at each of six sites of different typologies in France to assess the possible impact of PM source variability on PM10 OP apportionment. PM10 source-specific OPDTT and OPAA and out-of-sample apportionment accuracy vary substantially by model, highlighting the importance of model selection according to the datasets. Recommendations for the selection of the most accurate model are provided, encompassing considerations such as multicollinearity and homoscedasticity.</p
Brain death and postmortem organ donation: Report of a questionnaire from the CENTER-TBI study
Background: We aimed to investigate the extent of the agreement on practices around brain death and postmortem organ donation. Methods: Investigators from 67 Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study centers completed several questionnaires (response rate: 99%). Results: Regarding practices around brain death, we found agreement on the clinical evaluation (prerequisites and neurological assessment) for brain death determination (BDD) in 100% of the centers. However, ancillary tests were required for BDD in 64% of the centers. BDD for nondonor patients was deemed mandatory in 18% of the centers before withdrawing life-sustaining measures (LSM). Also, practices around postmortem organ donation varied. Organ donation after circulatory arrest was forbidden in 45% of the centers. When withdrawal of LSM was contemplated, in 67% of centers the patients with a ventricular drain in situ had this removed, either sometimes or all of the time. Conclusions: This study showed both agreement and some regional differences regarding practices around brain death and postmortem organ donation. We hope our results help quantify and understand potential differences, and provide impetus for current dialogs toward further harmonization of practices around brain death and postmortem organ donation
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