CARACTERIZACIÓN DE VIDRIOS PARA LA EVALUACÍÓN DEL AISLAMIENTO ACÚSTICO A RUIDO AÉREO

[ES] La principal aportación del trabajo es la formulación de una alternativa que facilita la determinación experimental del factor de pérdidas y, en consecuencia, mejorar las predicciones de aislamiento a ruido aéreo para vidrios con una o más capas intermedias sea cual fuere su naturaleza. Además, se realiza una revisión de las normativas relacionadas con los ensayos de los parámetros mecánicos necesarios para la caracterizar los vidrios, centrándonos en los monolíticos y los laminados. En efecto, uno de los problemas que se plantea en el contexto de la acústica de la edificación actualmente es el de cumplir con los requisitos de aislamiento acústico a ruido aéreo en fachada que exige el vigente Código Técnico de la Edificación (CTE). Como sabemos, en la fachada podemos distinguir la parte ciega y la parte hueca. La parte más débil en lo concerniente a aislamiento a ruido aéreo es la hueca (compuesta por el vidrio, carpintería y otros elementos). Si la carpintería es la adecuada, la superficie de vidrio se convierte en el elemento limitante. El Catálogo de Elementos Constructivos (CEC) del CTE, la propia norma UNE-EN 12758:2011, así como algunos, cada vez más, fabricantes ofrecen datos del aislamiento de vidrios simples, vidrios laminados y vidrios dobles. En el caso de vidrios laminados, estos datos se limitan únicamente en los que tienen un sola lámina intermedia y, además, no acústicos. Podemos hablar, por tanto, de una laguna de información en este sentido. Para obtener predicciones fiables de aislamiento acústico a ruido aéreo de particiones multicapa, como pueden ser los vidrios laminados es necesario disponer de las características mecánicas y una de las más relevantes es el factor de pérdidas.[EN] The main contribution of this paper is the formulation of an alternative to experimental determination of loss factor and, consequently, to improve the predictions of airborne sound insulation for any type of monolithic or laminated glass. In addition, a review of the standards related to measurement of mechanical parameters of glass is carried out, with particular interest in laminated glass Indeed, one of the problems that arise in the current context of building acoustics is to meet the requirements of facades airborne sound insulation of existing Building Technical Code (BTC). It is known that the blind and the hollow part of the facade should be distinguished. The weakest part regarding to airborne sound insulation is the empty one (consisting of glass, woodwork and other elements). Choosing an adequate woodwork makes the glass surface become the limiting factor. The Constructive Elements Catalog (CEC) of the BTC, the UNE-EN 12758:2011 standard, as well as some, increasingly, data vendors provide information about airborne sound insulation for monolithic glass, laminated glass and double glazing. In the case of laminated glass, these data are limited only to those with a single intermediate layer, and also nonacoustic. Can therefore be said that there is a gap of knowledge in this regard. To obtain reliable predictions of airborne sound insulation of multilayer partitions, such as laminated glass, mechanical characteristics must be known, being loss factor one of the most important.Alba Fernández, J.; Rey Tormos, RMD.; Ramis Soriano, J.; Bertó Carbó, L. (2012). CARACTERIZACIÓN DE VIDRIOS PARA LA EVALUACÍÓN DEL AISLAMIENTO ACÚSTICO A RUIDO AÉREO. Boletín de la Sociedad Española de Cerámica y Vidrio. 51(4):239-248. doi:10.3989/cyv.342012S23924851

Modelo óptico para acristalamientos multicapa

En el caso del vidrio laminado, dadas las múltiples configuraciones que pueden concebirse con propósitos arquitectónicos varios en la fase de diseño (estéticos, de eficiencia energética, seguridad o aislamiento acústico, principalmente), resulta de gran utilidad poder disponer de simulaciones computacionales de las propiedades ópticas en función de las propias de sus constituyentes (sustratos vítreos, láminas poliméricas y capas selectivas a la radiación solar). Los procedimientos para la determinación por cálculo de las magnitudes de caracterización óptica de este tipo de vidrios se encuentran actualmente en proceso de normalización por el CEN (Comité Europeo de Normalización). El estudio de vidrios laminados con capa selectiva interna, en contacto con la lámina polimérica, tiene un valor teórico especialmente significativo, al introducir reflectividad en el interior del sistema óptico multicapa. En este trabajo se presenta un modelo teórico basado en el método de matrices de transferencia particularizado para el cálculo de las propiedades ópticas del vidrio laminado con capas externas e internas. Los resultados de la simulación se comparan con datos experimentales obtenidos mediante espectrofotometría UV-VIS-NIR

Anàlisi del contingut en calci de la llet

Es presenta un treball de recerca de segon de Batxillerat on s'han provat diferents tècniques analítiques per determinar el contingut en calci d'una llet comercial. Combinant diferents mètodes s'ha aconseguit trobar una forma ràpida, senzilla i eficaç de valorar el contingut en calc

Secular changes in length of day: Effect of the mass redistribution

In this paper the secular change in the length of day due to mass redistribution effects is revisited using the Hamiltonian formalism of the Earth rotation theories. The framework is a two-layer deformable Earth model including dissipative effects at the core–mantle boundary, which are described through a coupling torque formulated by means of generalized forces. The theoretical development leads to the introduction of an effective time-averaged polar inertia moment, which allows us to quantify the level of core–mantle coupling throughout the secular evolution of the Earth. Taking advantage of the canonical procedure, we obtain a closed analytical formula for the secular deceleration of the rotation rate, numerical evaluation of which is performed using frequency-dependent Love numbers corresponding to solid and oceanic tides. With this Earth modeling, under the widespread assumption of totally coupled core and mantle layers in the long term response, a secular angular acceleration of − 1328.6′′ cy−2 is obtained, which is equivalent to an increase of 2.418 ms cy−1 in the length of day. The ocean tides and the semidiurnal band of the mass-redistribution-perturbing potential, mostly induced by the Moon, constitute the main part of this deceleration. This estimate is shown to be in very good agreement with recent observational values, and with other theoretical predictions including comparable modeling features

Proyecto básico de ampliación y mejora del puerto deportivo de La Goleta (T.M. Oliva, Valencia). Muelle perimetral y firmes

[EN] The present project entitled "Basic design for the extension and improvement of "La Goleta" marina (Oliva, Valencia)" has been elaborated as an end of degree project by all four members of the group, fourth year Civil Engineering students at Universitat Politéctica de Valencia. The objective is to develop a proposal for the expansion of the "La Goleta" marina, at the basic design stage. This proposal aims to improve the current situation of the marina so as to satisfy the growing needs of the marina's users. Above all this improvement consists of the execution of a new dock that hosts 184 new moorings and a dry dock with capacity for 130 vessels of less than 8 metres in length. To accommodate this increase in maritime area the current outer sea wall is set to be demolished and replaced by a new one which shelters the new docking area. Also, it is decided that the current dyke will be extended to minimize the ongoing problem of siltation in the marina and to improve its interior protection. Additionally, new vertical wharfs are projected for the berthing of new vessels, as well as two 140 metre quays with finger moorings intended to optimize the available space in the new dock. To meet the needs of the increased number of users, it¿s necessary to carry out a redistribution of the docks water and electricity supply and drainage network, as well as improving the dock¿s facilities.[CA] El present projecte denominat "Projecte bàsic d'ampliació i millora del Port Esportiu de "La Goleta" (T.M. Oliva, València) " s'ha realitzat com a Treball de Finalització de Grau conjunt dels quatre integrants del grup. L'objectiu és el de desenvolupar una proposta per a l'ampliació del Port Esportiu de "La Goleta", a nivell de projecte bàsic. Aquesta proposta pretén millorar la situació actual del port per a satisfer les necessitats creixents demandades pels usuaris del port. Principalment aquesta millora consisteix en l'execució d'una nova dàrsena que acull 184 nous amarris i una marina seca amb capacitat per a 130 embarcacions de menys de 8 metres d'eslora. Per poder albergar aquest increment de superfície marítima es proposa el desmantellament de l'actual contradic i l'execució d'un nou de tipologia de dic en talús que abrigui una nova zona d'atracada. A més, es decideix prolongar l'actual dic per minimitzar els problemes de aterraments que sofreix el port i per millorar l'abric de l'interior d'aquest. Per l'atracada de les noves embarcacions es disposa en el perímetre de molls vertical de blocs que permeten l'atracada de les noves embarcacions, a més per optimitzar l'espai marítim de la dàrsena es proposa l'execució de dos pantalàns de 140 metres amb amarrament mitjançant finger. Per a complir les necessitats del nou nombre d'usuaris es planifica una nova distribució de les xarxes d'abastiment, sanejament i electricitat i es milloren les instal·lacions.[ES] El presente proyecto denominado "Proyecto básico de ampliación y mejora del PuertoDeportivo de "La Goleta" (T.M. Oliva, Valencia)" se ha realizado como Trabajo de Fin de Grado conjunto de los cuatro integrantes del grupo. El objetivo es el de desarrollar una propuesta para la ampliación del Puerto Deportivo de "La Goleta", a nivel de proyecto básico. Dicha propuesta pretende mejorar la situación actual del puerto para satisfacer las necesidades crecientes demandadas por los usuarios del puerto. Principalmente esta mejora consiste en la ejecución de una nueva dársena que acoge 184 nuevos amarres y una marina seca con capacidad para 130 embarcaciones de menos de 8 metros de eslora. Para poder albergar este incremento de superficie marítima se propone el desmantelamiento del actual contradique y la ejecución de uno nuevo de tipología de dique en talud en talud que abrigue una nueva zona de atraque. Además, se decide prolongar el actual dique para minimizar los problemas de aterramiento que sufre el puerto y para mejorar el abrigo del interior de este. Para el atraque de las nuevas embarcaciones se dispone en el perímetro de muelles vertical de bloques que permite el atraque de las nuevas embarcaciones, además para optimizar el espacio marítimo de la dársena se propone la ejecución de dos pantalanes de 140 metros con amarre mediante finger. Para cumplir las necesidades del nuevo número de usuarios se planifica una nueva distribución de las redes de abastecimiento, saneamiento y electricidad y se mejoran las instalaciones.Martínez Baenas, A. (2015). Proyecto básico de ampliación y mejora del puerto deportivo de La Goleta (T.M. Oliva, Valencia). Muelle perimetral y firmes. http://hdl.handle.net/10251/52444.Archivo delegad

Forced nutations of a two-layer Earth in canonical formulation with dissipative Hori-like kernel

[EN] In this research, a modification of the Lie-Hori perturbation method developed by the authors in a recent investigation is used to compute the forced nutations of a non-rigid Earth model, including dissipative processes at the core-mantle boundary. The study is tackled within the Hamiltonian formalism of a two-layer Earth, where the viscous and electromagnetic couplings between mantle and core are introduced via generalized forces. The modified Lie-Hori method is introduced within the framework of the generalized Hamiltonian formalism. It, therefore, allows for calculating first-order perturbations in both conservative and non-conservative systems, while the classical Lie-Hori procedure is not designed to include generalized forces in the kernel to account for dissipative processes. Unlike other methods, this one presents the advantage of keeping the same dimensionality of the original problem, avoiding the doubling of the dimension of the phase space. With this mathematical refinement, differences in the derived nutation amplitudes at the microarcsecond level have been found when compared with the former, first approximation for dissipative systems based on damped oscillators —the only existing previous solution. Those figures are of relevance according to recent recommendations of the International Astronomical Union (IAU) and the International Association of Geodesy (IAG) based on the final report of the Joint Working Group on Theory of Earth rotation and validation.SIThis research has been partially supported by the Spanish project AYA2016-79775-P (AEI/FEDER, UE)

Secular changes in length of day: Effect of the mass redistribution

[EN] In this paper the secular change in the length of day due to mass redistribution effects is revisited using the Hamiltonian formalism of the Earth rotation theories. The framework is a two-layer deformable Earth model including dissipative effects at the core–mantle boundary, which are described through a coupling torque formulated by means of generalized forces. The theoretical development leads to the introduction of an effective time-averaged polar inertia moment, which allows us to quantify the level of core–mantle coupling throughout the secular evolution of the Earth. Taking advantage of the canonical procedure, we obtain a closed analytical formula for the secular deceleration of the rotation rate, numerical evaluation of which is performed using frequency-dependent Love numbers corresponding to solid and oceanic tides. With this Earth modeling, under the widespread assumption of totally coupled core and mantle layers in the long term response, a secular angular acceleration of − 1328.6′′ cy−2 is obtained, which is equivalent to an increase of 2.418 ms cy−1 in the length of day. The ocean tides and the semidiurnal band of the mass-redistribution-perturbing potential, mostly induced by the Moon, constitute the main part of this deceleration. This estimate is shown to be in very good agreement with recent observational values, and with other theoretical predictions including comparable modeling features.SIThis research has been developed within the framework of the IAU/IAG Joint Working Group 3.1: Improving Theories and Models of the Earth’s Rotation (ITMER)

Precession of the non-rigid Earth: Effect of the mass redistribution

[EN] This research is focused on determining the contribution to the precession of the Earth’s equator due to the mass redistribution stemming from the gravitational action of the Moon and the Sun on a rotating solid Earth. In the IAU2006 precession theory, this effect is taken into account through a contribution of −0.960 mas cy−1 for the precession in longitude (with the unspecific name of non-linear effect). In this work, the revised value of that second-order contribution reaches −37.847 mas cy−1 when using the Love numbers values given in IERS Conventions, and −43.945 mas cy−1 if those values are supplemented with the contributions of the oceanic tides. Such variations impose a change of the first-order precession value that induces relative changes of the Earth’s dynamical ellipticity of about 7.3 and 8.5 ppm, respectively. The corresponding values for the obliquity rate are 0.0751 and 0.9341 mas cy−1, respectively, in contrast to 0.340 mas cy−1 considered in IAU2006. The fundamentals of the modeling have been revisited by giving a clear construction of the redistribution potential of the Earth through the corresponding changes in the Earth tensor of inertia. The dynamical problem is tackled within the Hamiltonian framework of a two-layer Earth model, introduced and developed by Getino and Ferrándiz. This approach allows for the achievement of closed-analytical formulae for the precession in longitude and obliquity. It makes it possible to obtain numerical values for different Earth models once a set of associated Love numbers is selected. The research is completed with a discussion on the permanent tide and the related estimation of the variation of the second degree zonal Stokes parameter, J2, and also the indirect effects on nutations arising from the relative change of the Earth’s dynamicalSIThis work has been partially supported by the Spanish project AYA2016-79775-P (AEI/FEDER, UE)

El entremés y los comediantes durante el siglo de oro

Treballs Finals de Grau de Filologia Hispànica. Facultat de Filologia. Universitat de Barcelona, Curs: 2018-2019, Tutora: Lola Josa[spa] El entremés es un género teatral que alcanzó su esplendor durante el Siglo de Oro. En este trabajo, observaremos cómo fue su evolución a lo largo de los años, así como los diferentes aspectos que lo definen y que lo impulsaron al éxito. Al mismo tiempo, nos adentraremos en el oficio de los comediantes para conocer las diferentes funciones que desempeñaban en el desarrollo de una obra teatral, así como los elementos que aportaban al texto dramático y que terminaban de configurar la representación de un entremés.[eng] The entremés is a theatrical genre that reached its splendor during the Siglo de Oro. In this work, we will look at how its evolution went over the years, as well as the different aspects that define it and that drove it to success. At the same time, we will delve into the office of comedians to learn about the different roles they played in the development of a play, as well as the elements that contributed to the dramatic text and that finished shaping the representation of a entremés

Nutation of the non-rigid Earth: Effect of the mass redistribution

[EN] In this research, we computed the nutation of the figure axis for a non-rigid Earth model due to the mass redistribution resulting from the lunisolar attraction on the deformable Earth, thus extending our previous work on the precessional motion. The basic Earth model is a two-layer structure composed of a fluid core and an anelastic mantle. We used the Hamiltonian approach, leading to closed-form analytical formulae that describe the nutations in longitude and obliquity of the figure axis as a sum of Poisson and Oppolzer terms. Those formulae were evaluated assuming different Earth rheologies by means of the Love number formalism. In particular, we first computed the effect using the standard model of the International Earth Rotation and Reference Systems Service Conventions (2010) solid tides, and then the Love numbers computed by Williams and Boggs, accounting for the complete oceanic tide contribution, which should provide more consistent and updated values for the nutations. The main amplitudes correspond to the 18.6 yr nutation component and reach 201 μas and −96 μas in the in-phase components in longitude and obliquity, respectively. The obtained values differ greatly from those considered in the current nutation model, IAU2000, of the International Astronomical Union (IAU) – and later similar studies – which includes this effect under the denomination of non-linear terms and derives its numerical contribution on the basis of the Sasao, Okubo, and Saito framework. The differences are significant and reach more than 30 μas for some nutation amplitudes. They can be likely attributed to several factors: an incomplete modelling of the redistribution potential; a different treatment of the permanent tide; and the use of different oceanic tide models.S