Political discussions on Twitter during elections are dominated by those with extreme views

What do discussions on social media platforms tell us about political behaviour? Pablo Barberá and Gonzalo Rivero outline results from a study of 12,000 Spanish Twitter users during the 2011 Spanish general election and 50,000 American Twitter users during the 2012 U.S. presidential election. They find that users who were on the extreme left or right of an ideological scale played a disproportionately large part in political discussions during the election campaigns. They suggest that caution should therefore be exercised in using Twitter as a reliable source for gauging public opinion

Orientation Estimation by Means of Extended Kalman Filter, Quaternions, and Charts

An orientation estimation algorithm is presented. This algorithm is based on the Extended Kalman Filter, and uses quaternions as the orientation descriptor. For the filter update, we use measurements from an Inertial Measurement Unit (IMU). The IMU consists in a triaxial angular rate sensor, and an also triaxial accelerometer. Quaternions describing orientations live in the unit sphere of R4. Knowing that this space is a manifold, we can apply some basic concepts regarding these mathematical objects, and an algorithm that reminds the also called “Multiplicative Extended Kalman Filter” arises in a natural way. The algorithm is tested in a simulated experiment, and in a real one

Expected impact quantification–based reliability assessment methodology for Chilean copper smelting process: A case study

Currently, a lack of interpretation tools and methodologies hinders the ability to assess the performance of a single piece of equipment or a total system. Therefore, a reliability, availability, and maintainability analysis must be combined with a quantitative reliability impact analysis to interpret the actual performance and identify bottlenecks and improvement opportunities. This article proposes a novel methodology that uses reliability, availability, and maintainability analysis to quantify the expected impact. The strengths of the failure expected impact methodology include its ability to systematically and quantitatively assess the expected impact in terms of reliability, availability, and maintainability indicators and the logical configuration of subsystems and individual equipment, which show the direct effects of each element on the total system. This proposed analysis complements plant modeling and analysis. Determining the operational effectiveness impact, as the final result of the computation process, enables the quantitative and unequivocal prioritization of the system elements by assessing the associated loss as a ‘‘production loss’’ regarding its unavailability and effect on the system process. The Chilean copper smelting process study provides useful results for developing a hierarchization that enables an analysis of improvement actions that are aligned with the best opportunities

Dynamic perspectives on technology transfer: introduction to the special section

[EN] Theoretical frameworks acknowledge the dynamic and evolving nature of technology transfer. However, there is a scarcity of empirical work in the field incorporating a dynamic and longitudinal perspective. Several literature reviews call for technology transfer research agendas to include longitudinal studies. In response to such calls, this special section comprises selected contributions to the 2018 Technology Transfer Society (T2S) Conference which address this gap from different angles. The three qualitative and three quantitative works chosen contain research questions and methodologies related to dynamic aspects of technology transfer. We argue that historical and processual studies offer additional new directionsThe editors are grateful to 2018 T2S Conference participants for their comments on the papers published in this special section. We thank the Polytechnic University of Valencia and the Polytechnic Innovation City for their support and hospitality. We are indebted to the reviewers of the papers submitted to this special section. The Spanish Ministry of Science, Innovation, and Universities funded Joaquin M. Azagra-Caro's and Pablo D'Este's contribution to the special section as part of the CSO2016-79045-C2-2-R and the RTI2018-101232-B-100 Projects of the Spanish National R&D&I Plan, respectively.Barberá Tomás, JD.; Azagra-Caro, JM.; Deste Cukierman, P. (2021). Dynamic perspectives on technology transfer: introduction to the special section. The Journal of Technology Transfer. 1-9. https://doi.org/10.1007/s10961-021-09898-7S1

The critical periphery in the growth of social protests

Social media have provided instrumental means of communication in many recent political protests. The efficiency of online networks in disseminating timely information has been praised by many commentators; at the same time, users are often derided as “slacktivists” because of the shallow commitment involved in clicking a forwarding button. Here we consider the role of these peripheral online participants, the immense majority of users who surround the small epicenter of protests, representing layers of diminishing online activity around the committed minority. We analyze three datasets tracking protest communication in different languages and political contexts through the social media platform Twitter and employ a network decomposition technique to examine their hierarchical structure. We provide consistent evidence that peripheral participants are critical in increasing the reach of protest messages and generating online content at levels that are comparable to core participants. Although committed minorities may constitute the heart of protest movements, our results suggest that their success in maximizing the number of online citizens exposed to protest messages depends, at least in part, on activating the critical periphery. Peripheral users are less active on a per capita basis, but their power lies in their numbers: their aggregate contribution to the spread of protest messages is comparable in magnitude to that of core participants. An analysis of two other datasets unrelated to mass protests strengthens our interpretation that core-periphery dynamics are characteristically important in the context of collective action events. Theoretical models of diffusion in social networks would benefit from increased attention to the role of peripheral nodes in the propagation of information and behavior

Social media, political polarization, and political disinformation: a review of the scientific literature

The following report is intended to provide an overview of the current state of the literature on the relationship between social media; political polarization; and political “disinformation,” a term used to encompass a wide range of types of information about politics found online, including “fake news,” rumors, deliberately factually incorrect information, inadvertently factually incorrect information, politically slanted information, and “hyperpartisan” news. The review of the literature is provided in six separate sections, each of which can be read individually but that cumulatively are intended to provide an overview of what is known — and unknown — about the relationship between social media, political polarization, and disinformation. The report concludes by identifying key gaps in our understanding of these phenomena and the data that are needed to address them

Social media, political polarization, and political disinformation: a review of the scientific literature

The following report is intended to provide an overview of the current state of the literature on the relationship between social media; political polarization; and political “disinformation,” a term used to encompass a wide range of types of information about politics found online, including “fake news,” rumors, deliberately factually incorrect information, inadvertently factually incorrect information, politically slanted information, and “hyperpartisan” news. The review of the literature is provided in six separate sections, each of which can be read individually but that cumulatively are intended to provide an overview of what is known — and unknown — about the relationship between social media, political polarization, and disinformation. The report concludes by identifying key gaps in our understanding of these phenomena and the data that are needed to address them

Mysidacea associated with seagrass meadows off the southeast Iberian coast

El presente trabajo describe la taxocenosis de misidáceos asociados a fondos blandos someros con praderas de fanerógamas en el sudeste ibérico (El Campello, Alicante). Las muestras se obtuvieron mediante el método de la red de mano en diferentes tipos de hábitats: pradera de Posidonia oceanica (L.) Delile, 1813 y Cymodocea nodosa (Ucria) Ascherson, 1869, borde de pradera de posidonia y arena, entre 10 y 16 m de profundidad. Se identificaron en total ocho especies: Siriella clausii, S. armata, Mysidopsis gibbosa, Anchialina agilis, Leptomysis posidoniae, L. buergii, Mesopodopsis slabberi y Paramysis helleri, que mostraron abundancias distintas según el tipo de hábitat. Se incorpora una clave taxonómica para la determinación de las especies encontradas.The present paper describes the Mysidacea associated with seagrass meadows on sandy bottoms from the southeast Iberian coast (El Campello, Alicante). The mysids were obtained using the hand-net method in different types of habitats: Posidonia oceanica (L.) Delile, 1813 and Cymodocea nodosa (Ucria) Ascherson, 1869 meadows, posidonia meadows edges and sandy bottoms, at deep of 10 and 16 m. Eight species were identified: Siriella clausii, S. armata, Mysidopsis gibbosa, Anchialina agilis, Leptomysis posidoniae, L. buergii, Mesopodopsis slabberi y Paramysis helleri. Abundance varied according to the habitat. A key for the identification of these species is provided