Endogenous fisheries management in a stochastic model: Why do fishery agencies use TAC

The aim of this paper is to explain under which circumstances using TACs as instrument to manage a fishery along with fishing periods may be interesting from a regulatory point of view. In order to do this, the deterministic analysis of Homans and Wilen (1997)and Anderson (2000) is extended to a stochastic scenario where the resource cannot be measured accurately. The resulting endogenous stochastic model is numerically solved for finding the optimal control rules in the Iberian sardine stock. Three relevant conclusions can be highligted from simulations. First, the higher the uncertainty about the state of the stock is, the lower the probability of closing the fishery is. Second, the use of TACs as management instrument in fisheries already regulated with fishing periods leads to: i) An increase of the optimal season length and harvests, especially for medium and high number of licences, ii) An improvement of the biological and economic variables when the size of the fleet is large; and iii) Eliminate the extinction risk for the resource. And third, the regulator would rather select the number of licences and do not restrict the season length.

Políticas sobre la integración de las TIC en la escuela de la Comunidad Autónoma del País Vasco

[ES]En la Comunidad Autónoma Vasca se han tomado una serie de decisiones estratégicas materializadas en diversas políticas, planes institucionales e iniciativas con el objeto de integrar, usar e innovar con TIC en las escuelas. Desde iniciativas pretéritas centradas básicamente en la dotación de infraestructuras, pasando por el perfeccionamiento del profesorado, actualmente existe un modelo que intenta unir de facto la política de infraestructura y la formación del los docentes para una utilización eficiente de las TIC. La descripción y el análisis del impacto de las mismas en el entorno escolar es el objetivo de esta investigación. En este estudio se ha llevado a cabo una metodología de corte cualitativo basada en la recogida de ideas, opiniones y valoraciones de políticos, técnicos, directores de centros, así como de profesores mediante entrevistas en profundidad (N=25). Los diferentes agentes educativos entrevistados reconocen que a día de hoy el modelo propuesto que unifica lo tecnológico, lo psicopedagógico y lo organizativo adolece de falta de información eficaz y de financiación impidiendo claramente un impacto real en las escuelas.

Evaluación del uso de las tecnologías de la información y comunicación (tic) en el ámbito universitario

Este artículo dice que gracias a las TIC se abre un amplio ámbito de actuación fuera del sistema educativo no tradicional, el cual tendremos que diseñar y desarrollar desde los parámetros didácticos y formativos. En éstos nuevos espacios tecnológicos, los estudiantes y los profesores tienen que revisar sus roles y funciones para desarrollar con efectividad sus actividades y mutuamente reforzar los beneficios que se generen. Para poder tener una visión completa del impacto de las TIC en el ámbito global universitario es necesario extender éste estudio a estudiantes de diferentes años académicos, así como al conjunto de los tres Campus que constituyen la Universidad de País Vasco(UPV/EHU).

Best Proximity Points of Generalized Semicyclic Impulsive Self-Mappings: Applications to Impulsive Differential and Difference Equations

This paper is devoted to the study of convergence properties of distances between points and the existence and uniqueness of best proximity and fixed points of the so-called semicyclic impulsive self-mappings on the union of a number of nonempty subsets in metric spaces. The convergences of distances between consecutive iterated points are studied in metric spaces, while those associated with convergence to best proximity points are set in uniformly convex Banach spaces which are simultaneously complete metric spaces. The concept of semicyclic self-mappings generalizes the well-known one of cyclic ones in the sense that the iterated sequences built through such mappings are allowed to have images located in the same subset as their pre-image. The self-mappings under study might be in the most general case impulsive in the sense that they are composite mappings consisting of two self-mappings, and one of them is eventually discontinuous. Thus, the developed formalism can be applied to the study of stability of a class of impulsive differential equations and that of their discrete counterparts. Some application examples to impulsive differential equations are also given.

Sampling and learning the Mallows and Generalized Mallows models under the Cayley distance

[EN]The Mallows and Generalized Mallows models are compact yet powerful and natural ways of representing a probability distribution over the space of permutations. In this paper we deal with the problems of sampling and learning (estimating) such distributions when the metric on permutations is the Cayley distance. We propose new methods for both operations, whose performance is shown through several experiments. We also introduce novel procedures to count and randomly generate permutations at a given Cayley distance both with and without certain structural restrictions. An application in the field of biology is given to motivate the interest of this model.

An R package for permutations, Mallows and Generalized Mallows models

[EN]Probability models on permutations associate a probability value to each of the permutations on n items. This paper considers two popular probability models, the Mallows model and the Generalized Mallows model. We describe methods for making inference, sampling and learning such distributions, some of which are novel in the literature. This paper also describes operations for permutations, with special attention in those related with the Kendall and Cayley distances and the random generation of permutations. These operations are of key importance for the efficient computation of the operations on distributions. These algorithms are implemented in the associated R package. Moreover, the internal code is written in C++.

Effective and Robust Generalized Predictive Speed Control of Induction Motor

14 p.

TickTASKER, un nuevo proyecto empresarial en el entorno TIC

Business Plan Tick TASKER

Results on proximal and generalized weak proximal contractions including the case of iteration-dependent range sets

This paper presents some further results on proximal and asymptotic proximal contractions and on a class of generalized weak proximal contractions in metric spaces. The generalizations are stated for non-self-mappings of the forms for and , or , subject to and , such that converges uniformly to T, and the distances are iteration-dependent, where , , and are non-empty subsets of X, for , where is a metric space, provided that the set-theoretic limit of the sequences of closed sets and exist as and that the countable infinite unions of the closed sets are closed. The convergence of the sequences in the domain and the image sets of the non-self-mapping, as well as the existence and uniqueness of the best proximity points, are also investigated if the metric space is complete. Two application examples are also given, being concerned, respectively, with the solutions through pseudo-inverses of both compatible and incompatible linear algebraic systems and with the parametrical

Common Fixed Points of Generalized Rational Type Cocyclic Mappings in Multiplicative Metric Spaces

The aim of this paper is to present fixed point result of mappings satisfying a generalized rational contractive condition in the setup of multiplicative metric spaces. As an application, we obtain a common fixed point of a pair of weakly compatible mappings. Some common fixed point results of pair of rational contractive types mappings involved in cocyclic representation of a nonempty subset of a multiplicative metric space are also obtained. Some examples are presented to support the results proved herein. Our results generalize and extend various results in the existing literature.

Análisis de las innovaciones organizativas en la estructura empresarial y la influencia de las TIC

[ES]Este trabajo tiene como objetivo analizar la evolución de las estructuras organizativas adoptadas por las empresas, así como la introducción de las Tecnologías de la Información y la Comunicación en el sector empresarial. También se analizará el cambio de la integración vertical como estrategia, a la tendencia actual del outsourcing o externalización de tareas, además del crowdsourcing y sus dos vertientes más actuales, el crowdfunding y la tecnología Open Source. Finalmente se ilustra el proyecto con el análisis de un caso real centrado en la evolución del Grupo Eroski, su estrategia y modelo de negocio, así como la influencia de las TIC y sus movimientos en materia de outsourcing.