Adding local rotational degrees of freedom to ANC beams

This work shows a simple finite element formulation that enables to impose concentrated moments and rotations to ANC beams which are finite elements that lack rotational degrees of freedom. The idea is based on an specific constraint that expresses in a simple form the relation between the deformation of the beam and the rotation of any of its sections. By controlling this sectional rotation, moments and angles can be easily imposed on any model

An extra time duration model with application to unemployment duration under benefits in Spain

This paper postulates that the effect of unemployment benefits on the hazard rates changes considerably using a traditional duration model that uses only unemployment insurance (UI) data, or deals with unemployment assistance (UA) as a mere extension of UI, instead of an extra time duration model that accounts separately for transition rates to work of the unemployed who receive UI and UA. For UI recipients the hazard rate rises dramatically when UI benefits lapse approaches. On the contrary, for UA recipients the hazard rate remains flat or even has a slight fall nearby the UA lapse. Finally, there is a group of unemployed qualified for UA that quit UI due to the income fall that they will experience when they pass from UI to UA.unemployment benefits mixed proportional hazard model, unobserved heterogeneity

Publishing performance in economics: Spanish rankings (1990-1999)

This paper contributes to the growing literature that analyses the Spanish publishing performance in Economics throughout the 1990s. Several bibliometric indicators are used in order to provide Spanish rankings (of both institutions and individual authors) based on Econlit journals. Further, lists of the ten most influential authors and articles over that period, in terms of citations, are reported.Publicad

Quantum Ratchets for Quantum Communication with Optical Superlattices

We propose to use a quantum ratchet to transport quantum information in a chain of atoms trapped in an optical superlattice. The quantum ratchet is created by a continuous modulation of the optical superlattice which is periodic in time and in space. Though there is zero average force acting on the atoms, we show that indeed the ratchet effect permits atoms on even and odd sites to move along opposite directions. By loading the optical lattice with two-level bosonic atoms, this scheme permits to perfectly transport a qubit or entangled state imprinted in one or more atoms to any desired position in the lattice. From the quantum computation point of view, the transport is achieved by a smooth concatenation of perfect swap gates. We analyze setups with noninteracting and interacting particles and in the latter case we use the tools of optimal control to design optimal modulations. We also discuss the feasibility of this method in current experiments.Comment: Published version, 9 pages, 5 figure

Bibliotecas para un tiempo de crisis: edificio y personal

From a definition of “crisis”, and using a systemic methodology, here appears questions as books, publishing and bookshops. The core of this article is about the library in itself considered, as well as building, equipment and staff. In the conclusions it is signed up how crisis is a threat, obviously, but as well it represents opportunities.Partiendo de una definición de lo que para nosotros significa “crisis”, y utilizando una metodología sistémica, se analiza brevemente la situación del libro, las editoriales y las bibliotecas. El núcleo de este artículo está formado por el estudio de esa crisis en cuanto a las bibliotecas en su conjunto, así como respecto al edificio e instalaciones y al personal

Las bibliotecas como elementos para el desarrollo

Libraries are today considered as essential elements about development. We study the caracteristics of less developed countries, the actual meaning of the word development», the diverse considerations of some academics on the relationship between libraries and development and, as well, the question of publishing and reading in the so called «less developed countries». After the analysis of the actuation of international organizations as UNESCO and IFLA, we stablish some general conclusions about libraries and development.La consideración de las bibliotecas como elementos esenciales para el desarrollo es una creciente actualidad e importancia. Partimos de un estudio de las características esenciales de los países menos desarrollados y presentamos las nuevas perspectivas acerca de qué entendemos por desarrollo, considerado ya como una mejora integral del ser humano, no sólo en el aspecto económico, sino en el social, político, cultural, etc. Analizamos las aportaciones de diversos autores (Gorman, Mchombu...) respecto a la interacción bibliotecas y desarrollo, el problema de la edición de libros y la lectura en los países menos desarrollados y, así mismo, la situación de las bibliotecas en estos países menos desarrollados. Tras un análisis de la actuación en estos campos de organismo tales como la UNESCO e IFLA, concluimos en la esencial importancia que tiene un buen desarrollo bibliotecario para aumentar los niveles de calidad de vida en los países menos desarrollados

Factores de riesgo cardiovascular: el nivel de colesterol en sangre en aterosclerosis

En este trabajo de fin de grado se revisan las fuentes bibliográficas científicas de las últimas dos décadas sobre cómo influye el ejercicio físico en los factores de riesgo cardiovasculares. Se debate desde el punto de vista de las Ciencias de la Actividad Física y el Deporte los programas de ejercicio físico más adecuados para los factores de riesgo: hipertensión arterial, diabetes mellitus, tabaquismo y de forma más detenida el alto nivel de colesterol en sangre, relacionándolos con la ateroesclerosis y la cardiopatía isquémica. Además, se exponen los beneficios del ejercicio físico sobre estos factores de riesgo fundamentados mediante las rutas metabólicas de la obtención de energía.In this degree project we review the scientific bibliographic sources of the last two decades on how physical exercise influences cardiovascular risk factors. The most appropriate physical exercise programs to diminish risk factors are discussed from the point of view of the Physical Activity and Sports Sciences: hypertension, diabetes mellitus, smoking habit and more closely the high level of blood cholesterol, associating them with the atherosclerosis process and the ischemic heart disease. In addition, the benefits of physical exercise are exposed, based on the metabolic routes of obtaining energy.Universidad de Sevilla. Grado en Ciencias de la Actividad Física y del Deport

El sistema bibliotecario de la Universidad de A Coruña

Tras un análisis, como introducción general, de la situación actual de la universidad y de las bibliotecas universitarias, se estudian las cracterísticas de la Universidad de A Coruña; a continuación se muestran las líneas generales del Reglamento de la Biblioteca de esta universidad y finalmente se hace un estudio comparativo, a partir de los datos de REBIUN, de esta Biblioteca respecto a las demás bibliotecas universitarias españolas.After an introductory analysis of the present state of affairs at universities and university libraries, the article studies the characteristics of the University of La Coruña giving a general outline of this university’s system before making, on the basis of data facilitated by REBUIN, a comparative analysis of this library with respect to other Spanish university libraries