Producció de farratge amb cereals d'hivern

Peer Reviewe

The Zipf-Polylog distribution: Modeling human interactions through social networks

The Zipf distribution attracts considerable attention because it helps describe data from natural as well as man-made systems. Nevertheless, in most of the cases the Zipf is only appropriate to fit data in the upper tail. This is why it is important to dispose of Zipf extensions that allow to fit the data in its entire range. In this paper, we introduce the Zipf-Polylog family of distributions as a two-parameter generalization of the Zipf. The extended family contains the Zipf, the geometric, the logarithmic series and the shifted negative binomial with two successes, as particular distributions. We deduce important properties of the new family and demonstrate its suitability by analyzing the degree sequence of two real networks in all its range.Peer ReviewedPostprint (author's final draft

Randomly stopped extreme Zipf extensions

In this paper, we extend the Zipf distribution by means of the Randomly Stopped Extreme mechanism; we establish the conditions under which the maximum and minimum families of distributions intersect in the original family; and we demonstrate how to generate data from the extended family using any Zipf random number generator. We study in detail the particular cases of geometric and positive Poisson stopping distributions, showing that, in log-log scale, the extended models allow for top-concavity (top-convexity) while maintaining linearity in the tail. We prove the suitability of the models presented, by fitting the degree sequences in a collaboration and a protein-protein interaction networks. The proposed models not only give a good fit, but they also allow for extracting interesting insights related to the data generation mechanism.Peer ReviewedPostprint (author's final draft

Influència d'un cultiu de gramínia i d'un de lleguminosa en l'activitat biològica d'un sòl agrícola

Peer Reviewe

A characterization of the innovations of first order autoregressive models

“The final publication is available at Springer via http://dx.doi.org/10.1007/s00184-014-0497-5"Suppose that follows a simple AR(1) model, that is, it can be expressed as , where is a white noise with mean equal to and variance . There are many examples in practice where these assumptions hold very well. Consider . We shall show that the autocorrelation function of characterizes the distribution of W-t.Peer ReviewedPostprint (author's final draft

Prolamin proteins alteration in durum wheat by species of the genus Eurygaster and Aelia (Insecta, Hemiptera)

Postprint (published version

Efectes de la data de plantació i l'aplicació d'àcid giberèl·lic en el creixement i floració de Chrysanthemum Morifolium ramat

Peer Reviewe

Caracteristicas de la Alubia Ganxet (phaseolus vulgaris L.) y acciones para su conservación

Peer Reviewe

Proyecto, desarrollo y valoración en la UPC de un caso de feedforwarding en campus virtual

[EN] Several professors of UPC, UB, UAB, UIB, UOC and URV are investigating on "feed forwarding", a formative evaluation which is fed back immediately, which is not limited to "right-wrong", which is guiding rather than resolving, which is sufficiently individualized, which motivates reflection - action and which garantees a sustainable task for students and professors. The application inside the UPC has fallen on "Mathematics" at the College of Agriculture of Barcelona, during the first semester. It has designed an experience transferable to more topics, using props NTIC, and it has analyzed the level of achievements resulting from their deployment. To encourage learning, some questionnaires about the discipline were sent out, with and without feedback. Students have to first consider a feedback questionnaire, repeatedly until they have successfully answered all the questions, and then have faced a similar questionnaire without feedback. The experience has carried out involving two hundred students, with five double questionnaires generated by means of WIRIS (corresponding to the five themes of the course), using the Moodle 2.6.2. We have studied the contribution to academic achievement and satisfaction of agents, confirming increased dedication to matter, improvements (not maintained) in learning and positive evaluation of the step taken.[ES] Docentes de UPC, UB, UAB, UIB, UOC y URV investigamos sobre una evaluación formativa "feedforwarding", que realimente de inmediato, que no se limite al "correcto-incorrecto", que guíe más que resuelva, que sea suficientemente individualizada, que motive reflexión - acción y que genere un trabajo sostenible para alumnos y profesores. La aplicación en la UPC ha recaído sobre "Matemáticas" del primer cuatrimestre en la Escuela Superior de Agricultura de Barcelona. Se ha diseñado una experiencia transferible a más asignaturas, que usa apoyos de NTIC y que permite analizar eventuales logros resultantes de su despliegue. Para fomentar el aprendizaje se han administrado cuestionarios sobre la disciplina, con y sin realimentación. Los estudiantes han considerado primero un cuestionario con realimentación reiterada hasta que responden bien todas las preguntas y, posteriormente, han afrontado un cuestionario similar sin realimentación. Se ha actuado sobre unos doscientos estudiantes, con cinco cuestionarios dobles generados con WIRIS (correspondientes a los cinco temas de la asignatura), empleando la versión Moodle 2.6.2. Se ha estudiado la contribución al rendimiento académico y la satisfacción de los agentes, constatándose aumento de dedicación a la materia, mejoras (no duraderas) en el aprendizaje y valoración positiva del paso dado.Fabregat Fillet, J.; Pelayo Melero, I.; Valero Baya, J.; Ornat Longarón, C.; Achaerandio Puente, I.; Pineda Soler, E.; Buenestado Caballero, P. (2015). Proyecto, desarrollo y valoración en la UPC de un caso de feedforwarding en campus virtual. En In-Red 2015 - CONGRESO NACIONAL DE INNOVACIÓN EDUCATIVA Y DE DOCENCIA EN RED. Editorial Universitat Politècnica de València. https://doi.org/10.4995/INRED2015.2015.1554OC

Agentes causales y factores que predisponen al decaimiento del espárrago en Gavà, Barcelona

Postprint (published version