Binary Evolution and the Progenitor of SN 1987A

Since the majority of massive stars are members of binary systems, an understanding of the intricacies of binary interactions is essential for understanding the large variety of supernova types and sub-types. I therefore briefly review the basic elements of binary evolution theory and discuss how binary interactions affect the presupernova structure of massive stars and the resulting supernovae. SN 1987A was a highly anomalous supernova, almost certainly because of a previous binary interaction. The most likely scenario at present is that the progenitor was a member of a massive close binary that experienced dynamical mass transfer during its second red-supergiant phase and merged completely with its companion as a consequence. This can naturally explain the three main anomalies of SN 1987A: the blue color of the progenitor, the chemical anomalies and the complex triple-ring nebula.Comment: Proceedings for the conference "SN 1987A: Ten Years After", eds. M. M. Phillips and N. B. Suntzeff, which took place in 1997, but which still has to appear in print. Proceedings are made public as a source of historical referenc

Analysis of competitiveness in Colombian family businesses

Purpose: Building on the resource-based view and the configuration theory, the purpose of this study uses a systemic and multidimensional competitiveness index (CI) i.e. that incorporates system constraints among the 10 competitive pillars that form the index to assess the competitiveness level and the connection between competitiveness and economic performance [return on assets (ROA)] in family businesses (FBs). Design/methodology/approach: For the empirical application, the use a unique primary data set drawn from the global competitiveness project (www.gcp.org) that includes information for 77 Colombian FBs for 2017. Cluster analysis is used to evaluate the potential relationship between competitiveness, the configuration of competitive pillars and economic performance (ROA). Findings: The results for the CI show that the main competitive strengths of the analysed firms are related to the introduction of product innovations and networks (suppliers and customers), while the limited use of technologies in their operations and the low online presence are the main competitive weaknesses of these firms. Additionally, the findings of the cluster analysis reveal that different configurations of competitiveness pillars are associated with different performance levels. Therefore, the results contribute to identifying how specific strategies aimed at improving different resources or capabilities contribute to enhance business competitiveness, and ultimately, performance. Originality/value: By using an index number that takes into account the multiple interactions between resources and capabilities, the proposed analysis not only sheds light on the drivers of competitiveness i.e. resources and capabilities, and its connection to performance but also contributes to understanding the boundaries of the businesses’ competitiveness system, as well as the strategies that can potentially enhance competitiveness, and subsequently, business performance.Peer ReviewedPreprin

Cross-lingual Linking on the Multilingual Web of Data (position statement)

Recently, the Semantic Web has experienced signi�cant advancements in standards and techniques, as well as in the amount of semantic information available online. Even so, mechanisms are still needed to automatically reconcile semantic information when it is expressed in di�erent natural languages, so that access to Web information across language barriers can be improved. That requires developing techniques for discovering and representing cross-lingual links on the Web of Data. In this paper we explore the different dimensions of such a problem and reflect on possible avenues of research on that topic

Una actividad para el aprendizaje de la probabilidad, diseñada con el método histórico cultural de Vygotski y la teoría de la actividad de Leontiev

Se comienza viendo qué es la Zona de Desarrollo Próximo y qué convierte un material didáctico y tecnológico en una herramienta semiótica, aclarándose la intima conexión del pensamiento de Vygotski con el de Leontiev. Luego se describe la estructura, aplicación y resultados de un examen diagnóstico, usado como herramienta semiótica para introducir el tema de la probabilidad: su dialéctica con el azar y la incertidumbre, sus modalidades metodológicas y problemas básicos de modelación matemática, sus definiciones informales. Los resultados, puede apreciarse, fueron muy significativos

Using Cross-Lingual Explicit Semantic Analysis for Improving Ontology Translation

Semantic Web aims to allow machines to make inferences using the explicit conceptualisations contained in ontologies. By pointing to ontologies, Semantic Web-based applications are able to inter-operate and share common information easily. Nevertheless, multilingual semantic applications are still rare, owing to the fact that most online ontologies are monolingual in English. In order to solve this issue, techniques for ontology localisation and translation are needed. However, traditional machine translation is difficult to apply to ontologies, owing to the fact that ontology labels tend to be quite short in length and linguistically different from the free text paradigm. In this paper, we propose an approach to enhance machine translation of ontologies based on exploiting the well-structured concept descriptions contained in the ontology. In particular, our approach leverages the semantics contained in the ontology by using Cross Lingual Explicit Semantic Analysis (CLESA) for context-based disambiguation in phrase-based Statistical Machine Translation (SMT). The presented work is novel in the sense that application of CLESA in SMT has not been performed earlier to the best of our knowledge

Gender diversity in the board, women’s leadership and business performance

Purpose: This paper investigates how gender diversity in top management—i.e., boardroom and top management positions—impacts business performance among Colombian public businesses. Design/methodology/approach: Building on the Upper Echelon theory which emphasizes that gender in an important characteristic that influences top management’s decision making, we employ panel data models on a sample of 54 Colombian public businesses for the period 2008-2015 to test the proposed hypotheses relating gender diversity and subsequent business performance. Findings: The results support that gender diversity is positively associated with subsequent business performance. More concretely, we find that the relationship between gender diversity at the top of the corporate hierarchy—in our case, as CEO and in the top management team—and subsequent performance becomes more evident when performance is linked to business operations (ROA), while the positive effect of women’s representation in the boardroom and subsequent performance is significant when performance is measured via shareholder-oriented metrics (ROE). Originality/value: Few studies have addressed the role of gender diversity on performance in developing economies. This study contributes to better understand how gender diversity impacts performance in contexts where women are underrepresented in the top management, and where the appointment of women directors or managers is not driven by regulatory pressures.Peer ReviewedPostprint (author's final draft

Caminos de la reflexión En torno a la teoría orteguiana de las ideas y las creencias. Segunda Parte

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