Measuring Conduct and Cost Parameters in the Spanish Air Transport Market

This paper estimates a model of airline competition for the Spanish air transport market. I test the explanatory power of alternative oligopoly models with capacity constraints. In addition, I analyse the degree of density economies. Results show that Spanish airlines conduct follows a price-leadership scheme so that it is less competitive than the Cournot solution. I also find evidence that thin routes can be considered as natural monopolies.multiple equation models, air transportation, oligopoly

SDOC et TermWatch : deux méthodes complémentaires de cartographie de thèmes

Le but de cette communication est de comparer deux méthodes initialement destinées à la veille scientifique et technique dans une application de fouille de textes. Les deux méthodes proposent à l'utilisateur de visualiser les résultats d'une classification hiérarchique non supervisée de données textuelles sous forme d'une carte thématique. Elles sont cependant complémentaires puisque l'une, SDOC, est fondé sur l'analyse de la matrice de co-occurences et positionne les classes (clusters) sur le plan en fonction de leurs propriétés structurelles, tandis que l'autre, TermWatch, classifie les termes en fonction de leurs seuls liens de variation syntaxique et présente les résultats sous forme d'un réseau visualisable avec le logiciel AiSee, dont les liens sont d'autant plus resserrés que les classes sont supposées être thématiquement proches

Controlled composite processing based on off-stoichiometric thiol-epoxy dual-curing systems with sequential heat release (SHR)

Control of curing rate and exothermicity during processing of thermosetting composite materials is essential in order to minimize the formation of internal stresses leading to mechanical and dimensional defects in the samples, especially in thick composite samples. It was recently proposed that sequential heat release, an approach based on the kinetic control of the curing sequence of dual-curing thermosets, would enable a step-wise release of the reaction heat and therefore a better control of conversion and temperature profiles during the crosslinking stage. In this article, it is shown experimental proof of this concept obtained by means of an instrumented mold that can be used for the processing of small samples with and without carbon fiber reinforcement. Safe processing scenarios have been defined by numerical simulation using a simplified two-dimensional heat transfer model and validated experimentally.Peer ReviewedPostprint (author's final draft

Overview of INEX Tweet Contextualization 2014 track

International audience140 characters long messages are rarely self-content. The Tweet Contextualization aims at providing automatically information - a summary that explains the tweet. This requires combining multiple types of processing from information retrieval to multi-document sum- marization including entity linking. Running since 2010, the task in 2014 was a slight variant of previous ones considering more complex queries from RepLab 2013. Given a tweet and a related entity, systems had to provide some context about the subject of the tweet from the perspective of the entity, in order to help the reader to understand it

Évaluation de la contextualisation de tweets

National audienceCet article s'intéresse à l'évaluation de la contextualisation de tweets. La contextualisation est définie comme un résumé permettant de remettre en contexte un texte qui, de par sa taille, ne contient pas l'ensemble des éléments qui permettent à un lecteur de comprendre tout ou partie de son contenu. Nous définissons un cadre d'évaluation pour la contextualisation de tweets généralisable à d'autres textes courts. Nous proposons une collection de référence ainsi que des mesures d'évaluation adhoc. Ce cadre d'évaluation a été expérimenté avec succès dans la contexte de la campagne INEX Tweet Contextualization. Au regard des résultats obtenus lors de cette campagne, nous discutons ici les mesures utilisées en lien avec les autres mesures de la littérature

Overview of INEX Tweet Contextualization 2013 track

International audienceTwitter is increasingly used for on-line client and audience fishing; this motivated the tweet contextualization task at INEX. The objective is to help a user to understand a tweet by providing him with a short summary (500 words). This summary should be built automatically using local resources like the Wikipedia and generated by extracting relevant passages and aggregating them into a coherent summary. The task is evaluated considering informativeness which is computed using a variant of Kullback-Leibler divergence and passage pooling. Meanwhile effective readability in context of summaries is checked using binary questionnaires on small samples of results. Running since 2010, results show that only systems that efficiently combine passage retrieval, sentence segmentation and scoring, named entity recognition, text POS analysis, anaphora detection, diversity content measure as well as sentence reordering are effective

Cost-effectively 3d-printed rigid and versatile interpenetrating polymer networks

Versatile acrylate–epoxy hybrid formulations are becoming widespread in photo/thermal dual-processing scenarios, especially in 3D printing applications. Usually, parts are printed in a stereolithography or digital light processing (DLP) 3D printer, after which a thermal treatment would bestow the final material with superior mechanical properties. We report the successful formulation of such a hybrid system, consisting of a commercial 3D printing acrylate resin modified by an epoxy– anhydride mixture. In the final polymeric network, we observed segregation of an epoxy-rich phase as nano-domains, similar to what was observed in a previous work. However, in the current work, we show the effectiveness of a coupling agent added to the formulation to mitigate this segregation for when such phase separation is undesired. The hybrid materials showed significant improvement of Young’s modulus over the neat acrylate. Once the flexible, partially-cured material was printed with a minimal number of layers, it could be molded into a complex form and thermally cured. Temporary shapes were readily programmable on this final material, with easy shape recovery under mild temperatures. Inspired by repairable 3D printed materials described recently, we manufactured a large object by printing its two halves, and then joined them covalently at the thermal cure stage with an apparently seamless unionPeer ReviewedPostprint (author's final draft

El desarrollo profesional del docente de Educación Secundaria a partir del análisis de la cultura docente compartida

El artículo presenta algunos de los resultados obtenidos en un estudio sobre la cultura organizacional y docente de cuatro Institutos de Educación Secundaria de la provincia de Barcelona. Pone de relieve la necesaria modificación de la cultura docente para hacer frente a los retos educativos de la sociedad del siglo XXI. A partir de la adaptación de un cuestionario previamente elaborado para la Universidad por el equipo de investigación sobre "El cambio de cultura de las universidades catalanas al inicio del siglo XXI (CCUC, 2004) se averigua la percepción del profesorado respecto el perfil del profesorado, las metodologías docentes utilizadas, la concepción que tienen del alumnado, las estrategias y formas de evaluar el aprendizaje y la labor docente. Todo ello respecto el presente y lo que para ellos debería ser en un futuro. El estudio pone claramente de manifiesto que existe una insatisfacción del profesorado respecto a cada uno de los aspectos señalados y que ven necesaria una transformación de los IES.This article presents some of the results obtained in a study on the organizational and teaching culture of four high schools. The research, which has been carried out with the support of the DURSI at the province of Barcelona, emphasizes the need to transform the teaching culture so that the educational challenges of the 21st century society can be met. Data are obtained from an adapted version of a questionnaire which was previously designed for the university context by the research team CCUC (2004), and refer to teachers' perception on their teaching profile, teaching methodologies, their approach to students, and the assessment strategies and procedures concerning both teaching and learning. All these issues are explored in relation to both their actual state and their ideal prospects in the future. The research highlights teachers' discomfort with each of these issues as well as their perception on the need to transform high schools

INEX Tweet Contextualization Task: Evaluation, Results and Lesson Learned

Microblogging platforms such as Twitter are increasingly used for on-line client and market analysis. This motivated the proposal of a new track at CLEF INEX lab of Tweet Contextualization. The objective of this task was to help a user to understand a tweet by providing him with a short explanatory summary (500 words). This summary should be built automatically using resources like Wikipedia and generated by extracting relevant passages and aggregating them into a coherent summary. Running for four years, results show that the best systems combine NLP techniques with more traditional methods. More precisely the best performing systems combine passage retrieval, sentence segmentation and scoring, named entity recognition, text part-of-speech (POS) analysis, anaphora detection, diversity content measure as well as sentence reordering. This paper provides a full summary report on the four-year long task. While yearly overviews focused on system results, in this paper we provide a detailed report on the approaches proposed by the participants and which can be considered as the state of the art for this task. As an important result from the 4 years competition, we also describe the open access resources that have been built and collected. The evaluation measures for automatic summarization designed in DUC or MUC were not appropriate to evaluate tweet contextualization, we explain why and depict in detailed the LogSim measure used to evaluate informativeness of produced contexts or summaries. Finally, we also mention the lessons we learned and that it is worth considering when designing a task

PRL-3 overexpression in epithelial cells is induced by surrounding stromal fibroblasts

We isolate and culture carcinoma-associated fibroblasts (CAFs) from primary tumour (CAFpt), CAFs from corresponding synchronous liver metastasis (CAFlm) as well as normal colonic fibroblasts (NCF) from the same patient. From these cultures, conditioned media (CM) was obtained. Culture of a wide panel of colorectal and pancreatic cell lines in CM from CAFlm resulted in overexpression of mRNA PRL-3 and higher overexpression in CAFs than in non-activated fibroblasts. Moreover PRL-3 mRNA expression correlates with expression of α-SMA and deposition of collagen fibrils in the stroma. We demonstrate that products secreted by CAFs trigger PRL-3 overexpression in cancer cells. Identification of these factors may contribute to new stroma-targeted therapies for desmoplastic tumours