81 research outputs found

    Husimi-Wigner representation of chaotic eigenstates

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    Just as a coherent state may be considered as a quantum point, its restriction to a factor space of the full Hilbert space can be interpreted as a quantum plane. The overlap of such a factor coherent state with a full pure state is akin to a quantum section. It defines a reduced pure state in the cofactor Hilbert space. The collection of all the Wigner functions corresponding to a full set of parallel quantum sections defines the Husimi-Wigner reresentation. It occupies an intermediate ground between drastic suppression of nonclassical features, characteristic of Husimi functions, and the daunting complexity of higher dimensional Wigner functions. After analysing these features for simpler states, we exploit this new representation as a probe of numerically computed eigenstates of chaotic Hamiltonians. The individual two-dimensional Wigner functions resemble those of semiclassically quantized states, but the regular ring pattern is broken by dislocations.Comment: 21 pages, 7 figures (6 color figures), submitted to Proc. R. Soc.

    Helping Fact-Checkers Identify Fake News Stories Shared through Images on WhatsApp

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    WhatsApp has introduced a novel avenue for smartphone users to engage with and disseminate news stories. The convenience of forming interest-based groups and seamlessly sharing content has rendered WhatsApp susceptible to the exploitation of misinformation campaigns. While the process of fact-checking remains a potent tool in identifying fabricated news, its efficacy falters in the face of the unprecedented deluge of information generated on the Internet today. In this work, we explore automatic ranking-based strategies to propose a "fakeness score" model as a means to help fact-checking agencies identify fake news stories shared through images on WhatsApp. Based on the results, we design a tool and integrate it into a real system that has been used extensively for monitoring content during the 2018 Brazilian general election. Our experimental evaluation shows that this tool can reduce by up to 40% the amount of effort required to identify 80% of the fake news in the data when compared to current mechanisms practiced by the fact-checking agencies for the selection of news stories to be checked.Comment: This is a preprint version of an accepted manuscript on the Brazilian Symposium on Multimedia and the Web (WebMedia). Please, consider to cite it instead of this on

    Towards Understanding Political Interactions on Instagram

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    Online Social Networks (OSNs) allow personalities and companies to communicate directly with the public, bypassing filters of traditional medias. As people rely on OSNs to stay up-to-date, the political debate has moved online too. We witness the sudden explosion of harsh political debates and the dissemination of rumours in OSNs. Identifying such behaviour requires a deep understanding on how people interact via OSNs during political debates. We present a preliminary study of interactions in a popular OSN, namely Instagram. We take Italy as a case study in the period before the 2019 European Elections. We observe the activity of top Italian Instagram profiles in different categories: politics, music, sport and show. We record their posts for more than two months, tracking "likes" and comments from users. Results suggest that profiles of politicians attract markedly different interactions than other categories. People tend to comment more, with longer comments, debating for longer time, with a large number of replies, most of which are not explicitly solicited. Moreover, comments tend to come from a small group of very active users. Finally, we witness substantial differences when comparing profiles of different parties.Comment: 5 pages, 8 figure

    Innovating Management Control by Dynamic Analysis of Pareto in a Hotel Business

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    This paper deals with the Pareto Analysis of problems observed and criticized by clients in a hotel establishment in the municipality of Porto Velho, capital of the State of Rondocirc;nia. The general objective of the research is to study the use of Pareto Analysis in these problems that annoy the clients; (1), to group the data in descending order of frequency and to calculate the cumulative values (2), and indicating innovation for managerial control through a tool for Pareto Analysis in a dynamical way (3). The methodology of the qualitative-quantitative approach, of an exploratory nature, is adopted; the bibliographic survey and the field research are applied in support of the case study. Through the database system that the company under study possesses, the data necessary to be used in the Pareto Analysis are obtained, completing the first specific objective; the grouping of these data in descending order of absolute frequency, the calculation of the cumulative values, the preparation of the Pareto Diagram and the analysis carried out successfully completed the second specific objective; and finally the study is finished with the creation of a tool that allows a more dynamic analysis of the scenario in which the company is inserted, as a proposal of innovation for the institution to perform its practical and dynamic analyzes, useful in decision making. This study is a contribution of the academy to managers who work with complex decisions in hotel or related establishments interested in customer satisfaction

    Virtual Environment, Digital Hypertext, Reading and Writing in Foreign Language

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    This work intends to analyze - in an activity carried out with students from the third period of the Language (Spanish) undergraduate course of a college located in Itaperuna, a town in the State of Rio de Janeiro, Brazil - how the digital hyper textual reading can facilitate the selection of information in order to facilitate the writing process of texts in Spanish that can be broadcasted in the virtual environment, verifying how this may happen, so that these productions are shared, also allowing the interaction of the subjects with the language and with their peers. For this objective, we used the qualitative methodology (Erickson, 1986) with action research, seeking foundation in what theorists such as Lévy (1996, 1999), Coscarelli (2006, 2009), Gomes et al. (2015), Bannell et al. (2016), among others, investigate. As results, we emphasize that the subjects of the research actively participated in the construction of their own learning regarding the aspects covered in the foreign language class, and with this they were able to practice reading, writing, and the USAge of the vocabulary and grammar studied. Finally, we conclude that the hypertext worked here as an inclusive device, facilitator of reading and propitiator of writing, making the participant students authors of digital texts that provided them with learning throughout all the process they have been through

    On network backbone extraction for modeling online collective behavior

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    Collective user behavior in social media applications often drives several important online and offline phenomena linked to the spread of opinions and information. Several studies have focused on the analysis of such phenomena using networks to model user interactions, represented by edges. However, only a fraction of edges contribute to the actual investigation. Even worse, the often large number of non-relevant edges may obfuscate the salient interactions, blurring the underlying structures and user communities that capture the collective behavior patterns driving the target phenomenon. To solve this issue, researchers have proposed several network backbone extraction techniques to obtain a reduced and representative version of the network that better explains the phenomenon of interest. Each technique has its specific assumptions and procedure to extract the backbone. However, the literature lacks a clear methodology to highlight such assumptions, discuss how they affect the choice of a method and offer validation strategies in scenarios where no ground truth exists. In this work, we fill this gap by proposing a principled methodology for comparing and selecting the most appropriate backbone extraction method given a phenomenon of interest. We characterize ten state-of-the-art techniques in terms of their assumptions, requirements, and other aspects that one must consider to apply them in practice. We present four steps to apply, evaluate and select the best method(s) to a given target phenomenon. We validate our approach using two case studies with different requirements: online discussions on Instagram and coordinated behavior in WhatsApp groups. We show that each method can produce very different backbones, underlying that the choice of an adequate method is of utmost importance to reveal valuable knowledge about the particular phenomenon under investigation

    Public Management Focused to the Smart City

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    This study focuses on municipal management through information and communication technology in Smart City modeling. It presents a model for management of a Smart City with information technology resources to demonstrate the process of structuring integrated systems, analyze the benefits that this will bring by modeling local government activities, and introduce innovative measures for local government restructuring. It applies the simulated case study method and related procedures in a qualitative research approach, based on creativity and innovation. It reports the process of structuring integrated systems and analyses the benefits of a model of a Smart City. The Smart City will make the living conditions of the population much more pleasant and will reduce budgetary costs by deploying smart services. Eco-innovation, as set out in the Oslo Manual, extends to public businesses and is confirmed by the organizational innovation of civic processes. The solution in todayrsquo;s conditions is to manage cities using information technology and communication, where millions of citizens may enjoy the maximum benefit of a project of this kind. This study providing a framework for a smart city about its technology, innovation, and public affairs

    Towards Understanding Political Interactions on Instagram

    Get PDF
    Online Social Networks (OSNs) allow personalities and companies to communicate directly with the public, bypassing filters of traditional medias. As people rely on OSNs to stay up-to-date, the political debate has moved online too. We witness the sudden explosion of harsh political debates and the dissemination of rumours in OSNs. Identifying such behaviour requires a deep understaning on how people interact via OSNs during political debates. We present a preliminary study of interactions in a popular OSN, namely Instagram. We take Italy as a case study in the period before the 2019 European Elections. We observe the activity of top Italian Instagram profiles in different categories: politics, music, sport and show. We record their posts for more than two months, tracking "likes'' and comments from users. Results suggest that profiles of politicians attract markedly different interactions than other categories. People tend to comment more, with longer comments, debating for longer time, with a large number of replies, most of which are not explicitly solicited. Moreover, comments tend to come from a small group of very active users. Finally, we witness substantial differences when comparing profiles of different parties
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