A quantitative witness for Greenberger-Horne-Zeilinger entanglement

Along with the vast progress in experimental quantum technologies there is an increasing demand for the quantification of entanglement between three or more quantum systems. Theory still does not provide adequate tools for this purpose. The objective is, besides the quest for exact results, to develop operational methods that allow for efficient entanglement quantification. Here we put forward an analytical approach that serves both these goals. We provide a simple procedure to quantify Greenberger-Horne-Zeilinger-type multipartite entanglement in arbitrary three-qubit states. For two qubits this method is equivalent to Wootters' seminal result for the concurrence. It establishes a close link between entanglement quantification and entanglement detection by witnesses, and can be generalised both to higher dimensions and to more than three parties.

Roaming in the Mobile Internet: when coverage sharing agreements call for regulation

Revised: 2006-06

Moral Hazard and the Internal Organization of Joint Research

Revised 2006-06

Las iglesias prefeudales en Alava: cronotipología y articulación espacial

[ES]El artículo constituye un avance de un proyecto de investigación en curso sobre las iglesias alavesas anteriores a los siglos XII-XIII,invisibles hasta la fecha a una metodología tradicionalmente de base analógica y formal. Se efectúa una nueva propuesta de análisis experimentada ya en la catedral de Santa María de Vitoria-Gasteiz y que se articula de la manera siguiente: 1. Lettura veloce de los principales momentos constructivos de los templos seleccionados con el objeto de individualizar estratigráficamente la fase o fases anteriores al periodo «románico». 2. Individualización y registro de las variables técnicas y formales más representativas de esta primera fase constructiva en cada una de las iglesias objeto de estudio. 3. Identificación numérica de las variables seleccionadas. 4. Creación de una tabla analítica que recoja la presencia o ausencia de estas variables en cada uno de los edificios a estudiar. 5. Agrupamiento de los edificios que comparten variables entre sí. 6. Transformación de las asociaciones tecnotipológicas en tablas cronotipológicas, es decir, en indicadores cronológicos. Resultado de todo ello ha sido la individualización de seis grupos de iglesias que se articulan diacrónicamente entre los siglos IX y XII. A modo de conclusión se avanzan, finalmente, algunas consideraciones interpretativas sobre la naturaleza de estos templos de época prefeudal.

Selectivity, pulse fishing and endogenous lifespan in Beverton-Holt models

Optimal management in a multi-cohort Beverton-Holt model with any number of age classes and imperfect selectivity is equivalent to finding the optimal fish lifespan by chosen fallow cycles. Optimal policy differs in two main ways from the optimal lifespan rule with perfect selectivity. First, weight gain is valued in terms of the whole population structure. Second, the cost of waiting is the interest rate adjusted for the increase in the pulse length. This point is especially relevant for assessing the role of selectivity. Imperfect selectivity reduces the optimal lifespan and the optimal pulse length. We illustrate our theoretical findings with a numerical example. Results obtained using global numerical methods select the optimal pulse length predicted by the optimal lifespan rule.

Relaciones comerciales entre puertos franceses y guipuzcoanos en las décadas finales del siglo XVI y la primera mitad del siglo XVII: síntoma de vitalidad económica

[ES]El presente trabajo presenta una fuente documental infrautilizada, la de los libros de manifestaciones, que representa un interesantísimo instrumento de estudio para el conocimiento de la realidad comercial e industrial de la Guipúzcoa de los siglos XVI y XVII. Esta documentación permite matizar algunas de las afirmaciones que durante décadas han venido marcando la historiografía vasca sobre la tan manida “crisis del siglo XVII”, más en consonancia con los criterios que en los últimos años se vienen imponiendo en los ámbitos español y europeo. Las relaciones comerciales con puertos, principalmente franceses, que se pueden seguir a través de las mencionadas fuentes permiten seguir los fluidos intercambios y las llegadas de cereales y bastimentos, así como la salida de hierro y moneda desde algunos de los principales puertos guipuzcoanos. Una de las principales conclusiones es que la exportación de hierro a los puertos franceses tuvo continuidad a fines del siglo XVI y principios del siglo XVII

Democratic Values Transmission

This study addresses the issue of intergenerational transmission of democratic values embedded in social choice rules. We focus on a few rules which have been the focus of social choice theory: plurality, plurality with a runoff, majoritarian compromise, social compromise and Borda rule. We confront subjects with preferences profiles of a hypothetical electorate over a set of four alternatives. Different rules produce different outcomes and subjects decide which alternative should be chosen for the society whose preference profile is shown. We elicit each subject's preferences over rules and his/her parents' and check whether there is any relationship; 186 students and their parents attended the sessions at Istanbul Bilgi University. Overall, we find support for the hypothesis of parental transmission of democratic values and gender differences in the transmitted rule.

Colonization and development of Oribatida mite communities (Acari: Oribatida) in the forest reclaimed limestone mine dumps

In order to study the colonization and development of moss mites (Oribatida) communities in a Scots pine forest of a reclaimed limestone mine dump in Northern Poland, 3 plots from the dump were chosen. The selected plots differed in age, 5 years old, 35 and 50 years old. From a total of 30 samples 499 mites (Acari) were extracted in Tullgren funnel from which 262 were Oribatida. Abundance (N) was analyzed in all mites and after determining the species of both, juvenile and adult stages of oribatids, the following indices were analyzed: Abundance (N), Dominance (D), Species diversity (S), Species richness (s) and Shannon’s diversity index (H). Regarding to the results obtained; oribatid mites were dominant with the highest abundance in all assemblages (Plot 1: 139 Oribatida /299 Acari. Plot 2: 40/55 and Plot 3: 83/145). Tectocepheus velatus showed a very high dominance (45,99%) in plot 1; the highest value for Shannon’s diversity index belonged to plot 3. On the other hand, juvenile’s percentage was significantly higher than adult’s percentage, especially at plot 2 (95,02%). These results made us to conclude that the high abundance of oribatids in the youngest forest is due to T. velatus’s high abundance and that plot 3 is the best habitat for mites. Finally, the high occurrence of juvenile stages requires keeping on studying the area.

Feminización del hábito lector

[ES] En este artículo se exponen los resultados obtenidos en una investigación descriptiva sobre la feminización del ámbito lector en la Literatura Infantil y Juvenil (LIJ) vasca. La tesis que desde el principio sostuvo esta investigación se fundamentó en que el progresivo aumento de la presencia de la mujer en el sistema literario vasco tendría que reflejarse también de alguna manera en el ámbito lector. Se utilizó el cuestionario como instrumento metodológico y se eligió una población escolar de 300 niños y niñas de edades comprendidas entre los 11 y 12 años en Vitoria. Se verificó la hipótesis preliminar; no obstante, se detectó una tendencia clara a una mayor presencia femenina en las lecturas de las niñas que en la de los niños. Las lectoras leen un mundo imaginario en un 21.6% más femenino que los lectores.

Image-based delineation and classification of built heritage masonry

[EN]Fundación Zain is developing new built heritage assessment protocols. The goal is to objectivize and standardize the analysis and decision process that leads to determining the degree of protection of built heritage in the Basque Country. The ultimate step in this objectivization and standardization effort will be the development of an information and communication technology (ICT) tool for the assessment of built heritage. This paper presents the ground work carried out to make this tool possible: the automatic, image-based delineation of stone masonry. This is a necessary first step in the development of the tool, as the built heritage that will be assessed consists of stone masonry construction, and many of the features analyzed can be characterized according to the geometry and arrangement of the stones. Much of the assessment is carried out through visual inspection. Thus, this process will be automated by applying image processing on digital images of the elements under inspection. The principal contribution of this paper is the automatic delineation the framework proposed. The other contribution is the performance evaluation of this delineation as the input to a classifier for a geometrically characterized feature of a built heritage object. The element chosen to perform this evaluation is the stone arrangement of masonry walls. The validity of the proposed framework is assessed on real images of masonry walls.

Documentación espacial del patrimonio: preservación de la información. Necesidades, posibilidades, estrategias y estándares

[ES] La parte práctica de esta tesis se centra en un proyecto ERASMUS realizado en el Monasterio de San Prudencio de Monte Laturce (Clavijo, La Rioja). Dicho proyecto aparece descrito en varios registros de este mismo repositorio a los que se puede acceder a través del siguiente:

Euskalaritzaren historiaren ikerketa-norabideak: zenbait proposamendu

[EN] The aim of this paper is to propose some lines of investigation and new methods that can be followed in order to increase our knowledge of the History of Basque Linguistics. The main claim put forward here is that we must profit from the new methodological innovations developed by the H istoriography of Linguistics since the 60's. In the first section, different aspects are mentioned of the relevance of the study of Basque Linguistic Historiography. The second section comments on the boom of the Historiography of Linguistics from the 60's, its causes and its consequences; furthermore, it reports on the methodological models emerged from the discussions since then (as shown in works by Koerner, Swiggers, and many others). The third section points out some difficulties and challenges of the study of the History of Basque Linguistics, and suggests both some priorities for that study and possible lines of investigation. In order to illustrate the different points made throughout the paper, the reader is referred, when possible, to examples chosen from recent investigations or from future topics of research.