686 research outputs found
Loop quantization of the Gowdy model with local rotational symmetry
We provide a full quantization of the vacuum Gowdy model with local
rotational symmetry. We consider a redefinition of the constraints where the
Hamiltonian Poisson-commutes with itself. We then apply the canonical
quantization program of loop quantum gravity within an improved dynamics
scheme. We identify the exact solutions of the constraints and the physical
observables, and we construct the physical Hilbert space. It is remarkable that
quantum spacetimes are free of singularities. New quantum observables naturally
arising in the treatment partially codify the discretization of the geometry.
The preliminary analysis of the asymptotic future/past of the evolution
indicates that the existing Abelianization technique needs further refinement.Comment: 19 pages, 1 fi
Scuba diving in secondary school: a practical proposal
Resumen tomado de la publicaciónLa presente comunicación propone el buceo como una propuesta práctica dentro del área de Educación Física en Educación Secundaria Obligatoria. Para la práctica del buceo la Región de Murcia ofrece múltiples posibilidades debido a la riqueza marina que posee. Se pretende ofrecer a los alumnos la posibilidad de iniciarse en esta actividad para contribuir a consolidar la práctica deportiva en el tiempo libre y de ocio. Todo esto sin olvidar la importancia de la conservación y mejora del medio natural. El diseño de la propuesta práctica se ha realizado teniendo en cuenta la legislación vigente y la realidad educativa.ES
Proceedings of the First PhD Symposium on Sustainable Ultrascale Computing Systems (NESUS PhD 2016)
Proceedings of the First PhD Symposium on Sustainable Ultrascale Computing Systems (NESUS PhD 2016) Timisoara, Romania. February 8-11, 2016.The PhD Symposium was a very good opportunity for the young researchers to share information and knowledge, to
present their current research, and to discuss topics with other students in order to look for synergies and common research
topics. The idea was very successful and the assessment made by the PhD Student was very good. It also helped to
achieve one of the major goals of the NESUS Action: to establish an open European research network targeting sustainable
solutions for ultrascale computing aiming at cross fertilization among HPC, large scale distributed systems, and big
data management, training, contributing to glue disparate researchers working across different areas and provide a meeting
ground for researchers in these separate areas to exchange ideas, to identify synergies, and to pursue common activities in
research topics such as sustainable software solutions (applications and system software stack), data management, energy
efficiency, and resilience.European Cooperation in Science and Technology. COS
On the trail of grammaticalization in progress: has el que become a compound relative pronoun in the history of Spanish prepositional relative clauses?
In this paper, we examine the grammatical status of el que in Spanish
prepositional relative clauses (el lugar en el que vivo) [the place where I live]
from a variationist perspective of the theory of grammaticalization. At least from
the nineteenth century onwards, several authors have defended the nature of
el que as a compound relative pronoun, even if these forms continue alternating
today with others without the article [el lugar en que vivo], in contrast to el cual,
a fully grammaticalized relative since the late fifteenth century.
Based on a 3,200,000 word corpus of immediacy text (mainly private
letters), we test the hypothesis of el que being a case of grammaticalization in
progress from a variationist point of view, examining in depth what happens
inside the grammar and the socio-stylistic matrix in different periods of history,
from 1700 to 1960. The idea underlying this approach is that the structure of
changes as well as the grammaticalization in progress can be inferred from the
comparative analysis between different quantitative magnitudes of functionally
similar variants. To do so, we have performed three independent mixed-effects
regression analyses (Rbrul), one for each century.
The results of these comparative analyses confirm the progression of el que
in prepositional subordinate clauses between the early eighteenth century and
the first half of the twentieth. Yet, this progression has taken place at a slow
pace and, objectively, can only be described as moderate. Moreover, a number
of elements of continuity in history are revealed, such as several conditioning
factors that are systematically selected and with the same explanatory direction
in all periods. This casts serious doubt on the existence of a grammaticalization
in progress in the case of el que, and sees the evolution as not essentially
different from other morphosyntactic changes that have taken place in the
history of Spanish
The refuge of a dying variant within the grammar: Patterns of change and continuity in the Spanish verbal periphrasis haber de + infinitive over the past two centuries
Based on a corpus of ego-documents (private letters, diaries, memoirs) from the 19th and the first half of the 20th centuries, this paper presents a variationist comparative study to determine the fate of the modal periphrasis haber de + infinitive in the history of modern Spanish. Detailed analysis of the envelope of variation enables us to show that, despite an abrupt decline in the selection of haber de relative to tener que, both 'to have to', grammatical environments that favor its use remain in the mid-20th century. Many of the factor groups and the hierarchy of constraints during this period are similar to those that operated in previous periods. Nevertheless, a generalized decrease in the explanatory power of these factor groups, as well as some divergent patterns within several of these groups are also observed, mainly as a result of the fact that haber de + infinitive is increasingly relegated to some restricted areas of the grammar and lexicon. Based on these results, some theoretical implications for changing rates and constraints in language change and grammaticalization are discussed
The survival of deber de + infinitive in modern Spanish (18th-20th c.)
As part of a project on historical sociolinguistic based in the language of immediacy texts, data from this variationist analysis show how, despite the sharp decline in the uses of deber de + infinitive from the eighteenth century onwards, a number of linguistic and extralinguistic factors come together to stop a process that otherwise would have led to the final victory of the non-prepositional variant. Moreover, the study indicates the existence of a relative continuity with distributional patterns observed earlier in the classical period, that we have discussed elsewhere.En el marco de un proyecto de sociolingüística histórica sobre textos de
inmediatez comunicativa, los datos de este análisis variacionista muestran cómo, a pesar del descenso brusco en los empleos de deber de + infinitivo a partir del siglo XVIII,
una serie de factores lingüísticos y extralingüísticos se dan cita para frenar un proceso
que, de otro modo, hubiera supuesto el triunfo definitivo de la variante no prepositiva.
Por lo demás, el análisis empírico señala la existencia de una relativa continuidad con
los patrones distribucionales observados en el periodo clásico anterior, que hemos analizado en otro lugar
Viabilidad legal y económica de un sistema de microgeneración un un edificio de viviendas
Hasta el momento actual, la cogeneración ha sido utilizada en la industria con buenos resultados, hace no muchos años se ha empezado a utilizar en edificios para realizar sistemas de ACS y calefacción en viviendas, llamándose microcogeneración por ser cogeneración a menor escala, hasta 1MW para ser más exactos. En este proyecto se va a tratar de explicar cómo se implanta un sistema de microcogeneración en un edificio, explicando que sistema se ha elegido y los pasos que hay que seguir dentro del ahorro energético y régimen especial para que el proyecto sea un proyecto que cumpla con la legislación vigente en estos campos. Además de la viabilidad legal del proyecto se va a tratar de realizar un estudio económico que pruebe: - Las ventajas que aporta este sistema en comparación con los sistemas convencionales que se instalan para ACS y calefacción en edificios. - El número de motores necesario para que el edificio en estudio saque la mayor rentabilidad al sistema. - Que los sistemas de microcogeneración en edificios de viviendas es una buena alternativa a los sistemas solares térmicos. Para acabar se realizará una síntesis del proyecto donde se explicarán las conclusiones obtenidas.Ingeniería Industria
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