HCHO, H 2 O 2 und CH 3 OOH in der Troposphäre

In dieser Arbeit wurden im Rahmen der UTOPIHAN- und HOHPEX04-Projekte Peroxid- und Formaldehydmessungen in der Troposphäre durchgeführt und wissenschaftlich interpretiert. Die Messungen während UTOPIHAN fanden dabei an Bord eines für Forschungszwecke umgerüsteten Flugzeuges (Learjet 35A) im Wesentlichen in der freien, insbesondere in der oberen Troposphäre über Europa statt. Die Messungen während HOHPEX04 waren hingegen als Bodenmessungen an der sich abwechselnd in der bodennahen Grenzschicht und in von dieser Schicht entkoppelten Luftmassen liegenden Bergstation Hohenpeißenberg (bayerisches Voralpenland) konzipiert. Um eine quantitative Auswertbarkeit der Messungen sicherzustellen, wurden die verwendeten, auf chemischer Derivatisierung und fluorimetrischer Detektion basierenden Messgeräte AL 2001CA (Peroxide) und AL 4021 (Formaldehyd) (AEROLASER) genau charakterisiert. Dabei wurde speziell die bekannte Ozoninterferenz beider Geräte in einer großen Zahl von Laborexperimenten mit unterschiedlichen Randbedingungen bezüglich Wasserdampf- und Kohlenwasserstoffgehalt der Luft untersucht. Für beide Verbindungen wurden Höhen- sowie Breitenprofile erstellt und mit Ergebnissen eines 3D-Chemie-Transport-Modells (CTM) sowie früherer Studien verglichen. In einem weiteren Kapitel werden Ergebnisse einer quantitativen Studie zum Einfluss hochreichender Konvektion auf das HCHO-Budget in der mittleren und oberen Troposphäre präsentiert. Diese Studie kommt zu dem Schluss, dass der rasche Aufwärtstransport von Vorläufergasen von HCHO und HOx wie Methanol, Aceton und sogar gut löslicher Spurengase wie CH3OOH beziehungsweise H2O2 aus der Grenzschicht einen signifikanten, auf Grund der längeren Lebensdauer von NOx über mehrere Tage andauernden und damit großräumigen Einfluss auf die Budgets von HCHO, HOx und auch O3 in der oberen Troposphäre haben kann. Die Befunde der Studie legen desweiteren nahe, dass fehlerhafte Modellvorhersagen für die NO-Mischungsverhältnisse in der Tropopausenregion, die zum Beispiel mit Mängeln des Modells bezüglich der Höhe der Konvektion und des Stratosphären-Troposphären-Austauschs zu tun haben, hauptverantwortlich sind für gefundene Differenzen zwischen Messdaten und dem verwendeten 3D-Chemie-Transport-Modell. Um die Signifikanz der Aussagen zu erhöhen, wurde eine Sensitivitätsstudie durchgeführt, in der die Konzentration einiger chemischer Verbindungen sowie die Photolyseraten variiert wurden. Eine weitere Studie zum Einfluss verschiedener Parameter auf das CH3OOH/H2O2-Verhältnis kommt zu dem Schluss, dass dieses Verhältnis keinen idealen Indikator für Wolkenprozessierung von Luftmassen darstellt, während eine signifikant positive Abweichung vom H2O2/H2O-Verhältnis in der oberen Troposphäre ein guter Indikator für rasch aufwärts transportierte Luftmassen sein kann. Im Rahmen dieser Studie werden auch Höhen- und Breitenprofile des CH3OOH/H2O2-Verhältnisses diskutiert. In einer letzten Untersuchung zu HCHO-Messungen am Observatorium Hohenpeißenberg im Sommer 2004 werden für die in zwei Windrichtungssektoren eingeteilten Daten Korrelationen anderer Spurengase wie O3, PAN, CO, NOy und Isopren mit HCHO interpretiert. In diesem Zusammenhang wird auch versucht, den beobachteten Tagesgang von HCHO zu erklären.

Patogeni e zecche vettrici: studio epidemiologico in parchi pubblici dell'Emilia Romagna

Le malattie trasmesse da zecche sono un importante problema sia per la salute animale che per quella umana e negli ultimi decenni hanno aumentato notevolmente la loro diffusione, in seguito ai cambiamenti climatici, che hanno permesso la distribuzione delle zecche in aree prima non interessate. Per tale motivo si è deciso di effettuare un’indagine sulla diffusione delle zecche e sui patogeni da loro trasmessi, mediante campionamenti sia a livello ambientale, sia su animali e umani infestati in quattro siti di tre parchi dell’Emilia Romagna, dove non risultavano precedenti segnalazioni, nelle province di Bologna e Ravenna, da Aprile a Ottobre 2010. In totale sono state raccolte 8212 zecche. Dall’ambiente sono state campionate 6734 larve, 1344 ninfe, 61 adulti; dagli animali e da persone sono stati raccolti 68 adulti e 5 ninfe appartenenti a diverse specie di Ixodidae. Sono state condotte analisi sull’abbondanza delle zecche nelle diverse aree di raccolta, in funzione del periodo di campionamento, della temperatura e dell’umidità relativa misurata a 5 cm dal suolo al momento del campionamento e della vegetazione. Su tutti gli individui adulti e su pool di ninfe e di larve, per un totale di 393 campioni, sono state condotte analisi di tipo molecolare per la ricerca di piroplasmi, Anaplasma phagocytophilum e Borrelia burgdorferi s.l. Attraverso la PCR e il sequenziamento, è emerso che il 7,6% dei campioni era positivo per piroplasmi, tra i quali è stata riscontrata anche la presenza delle specie zoonosiche Babesia EU1 e B. divergens. La real-time PCR eseguita solo sui campioni costituiti da ninfe e adulti ha evidenziato una prevalenza del 9,2% per A. phagocytophilum e del 21,6% per B. burgdorferi s.l. Su questi patogeni sono state quindi condotte analisi di tipo filogenetico. In alcuni campioni sono state riscontrate coinfezioni con combinazioni di due patogeni contemporaneamente.

Austauschprozesse an Tropopausenfalten extratropischer Zyklonen

Troposphärisches Ozon ist bekannt als wichtiges Oxidationsmittel und als Vorläufergas hoch reaktiver Radikale. Es zählt zu den wichtigsten Treibhausgasen und wirkt bei hohen Konzentrationen an der Erdoberfläche giftig für alle Lebewesen. Zwar wird der Großteil des troposphärischen Ozons photochemisch produziert, ein erheblicher Anteil hat aber stratosphärischen Ursprung und wird entlang von Tropopausenfalten in Zyklonen in die Troposphäre transportiert. Dieser Transport von Luftmassen aus der Stratosphäre in diernTroposphäre (STT) kann zu einem kurzzeitigen, starken Ozonanstieg am Boden führen und langfristig die Chemie der Troposphäre beeinflussen. Die Quantifizierung des Ozoneintrages und die Identifizierung der dafür verantwortlichen Prozesse ist mit großen Unsicherheiten belastet und ein aktuelles Forschungsthema.rnAufgrund ihrer groben Auflösung ist es mit globalen Modellen nicht möglich, die Details dieser STT-Prozesse zu erfassen. Deshalb wird in dieser Arbeit das Modellsystem MECO(n) genutzt, welches das regionale Atmosphärenchemie- und Klimamodell COSMO/MESSy mit dem globalen Chemie-Klimamodell ECHAM5/MESSy (EMAC) koppelt. Eine einheitliche Prozessparametrisierung ermöglicht konsistente, simultane Simulationen in verschiedenen Modellauflösungen. Ein als Teil dieser Arbeit neu entwickeltes Submodell erlaubt die Initialisierung künstlicher, passiver Tracer in Abhängigkeit verschiedener Variablen. Mit einem auf diese Weise freigesetzten, stratosphärischen Tracer lässt sich Ozon mit stratosphärischer Herkunft von solchem, das photochemisch produziert wurde, unterscheiden.rnIm Rahmen einer Fallstudie werden die Austauschprozesse an einer Tropopausenfalte sowohl aus der Eulerischen, als auch aus der Lagrangeschen Perspektive betrachtet. Die Analyse der STT-Prozesse zeigt, dass Luftmassen aus der Stratosphäre durch turbulente und diabatische Prozesse am Rand der Tropopausenfalte in die Troposphäre gelangen und anschließend bis zum Boden transportiert werden. Diese absinkenden, stratosphärischen Luftmassen führen in den Simulationen zu Ozonanstiegen am Boden, die mit Beobachtungsdaten evaluiert werden können. Es wird gezeigt, dass die Ergebnisse der feiner auflösendenrnModellinstanz gut mit den Messungen übereinstimmen.rnIn einer Lagrangeschen Analyse lassen sich Mischungszeitskalen für STT-Prozesse bestimmen. Es wird gezeigt, dass Luftpakete, die sich länger als zehn Stunden in der Troposphäre aufhalten, diese durch den Eintrag ihrer stratosphärischen Tracereigenschaften beeinflussen und daher nicht vernachlässigbar sind. Eine weitere Studie gibt Aufschluss über die Effektivität der Mischung an Tropopausenfalten: Fast die gesamte Luftmasse, die sich zu einem bestimmten Zeitpunkt in der Tropopausenfalte befindet, gelangt innerhalb von zwei Tagen in die Troposphäre.

Stabilität und Transport in der planetaren Grenzschicht - Untersuchungen mit Radiosonden- und Spurengasmessungen während PARADE

Die vorliegende Arbeit untersucht die Struktur und Zusammensetzung der untersten Atmosphäre im Rahmen der PARADE-Messkampagne (PArticles and RAdicals: Diel observations of the impact of urban and biogenic Emissions) am Kleinen Feldberg in Deutschland im Spätsommer 2011. Dazu werden Messungen von meteorologischen Grundgrößen (Temperatur, Feuchte, Druck, Windgeschwindigkeit und -richtung) zusammen mit Radiosonden und flugzeuggetragenen Messungen von Spurengasen (Kohlenstoffmonoxid, -dioxid, Ozon und Partikelanzahlkonzentrationen) ausgewertet. Ziel ist es, mit diesen Daten, die thermodynamischen und dynamischen Eigenschaften und deren Einfluss auf die chemische Luftmassenzusammensetzung in der planetaren Grenzschicht zu bestimmen. Dazu werden die Radiosonden und Flugzeugmessungen mit Lagrangeschen Methoden kombiniert und es wird zwischen rein kinematischen Modellen (LAGRANTO und FLEXTRA) sowie sogenannten Partikeldispersionsmodellen (FLEXPART) unterschieden. Zum ersten Mal wurde im Rahmen dieser Arbeit dabei auch eine Version von FLEXPART-COSMO verwendet, die von den meteorologischen Analysefeldern des Deutschen Wetterdienstes angetrieben werden. Aus verschiedenen bekannten Methoden der Grenzschichthöhenbestimmung mit Radiosondenmessungen wird die Bulk-Richardson-Zahl-Methode als Referenzmethode verwendet, da sie eine etablierte Methode sowohl für Messungen und als auch Modellanalysen darstellt. Mit einer Toleranz von 125 m, kann zu 95 % mit mindestens drei anderen Methoden eine Übereinstimmung zu der ermittelten Grenzschichthöhe festgestellt werden, was die Qualität der Grenzschichthöhe bestätigt. Die Grenzschichthöhe variiert während der Messkampagne zwischen 0 und 2000 m über Grund, wobei eine hohe Grenzschicht nach dem Durchzug von Kaltfronten beobachtet wird, hingegen eine niedrige Grenzschicht unter Hochdruckeinfluss und damit verbundener Subsidenz bei windarmen Bedingungen im Warmsektor. Ein Vergleich zwischen den Grenzschichthöhen aus Radiosonden und aus Modellen (COSMO-DE, COSMO-EU, COSMO-7) zeigt nur geringe Unterschiede um -6 bis +12% während der Kampagne am Kleinen Feldberg. Es kann allerdings gezeigt werden, dass in größeren Simulationsgebieten systematische Unterschiede zwischen den Modellen (COSMO-7 und COSMO-EU) auftreten. Im Rahmen dieser Arbeit wird deutlich, dass die Bodenfeuchte, die in diesen beiden Modellen unterschiedlich initialisiert wird, zu verschiedenen Grenzschichthöhen führt. Die Folge sind systematische Unterschiede in der Luftmassenherkunft und insbesondere der Emissionssensitivität. Des Weiteren kann lokale Mischung zwischen der Grenzschicht und der freien Troposphäre bestimmt werden. Dies zeigt sich in der zeitlichen Änderung der Korrelationen zwischen CO2 und O3 aus den Flugzeugmessungen, und wird im Vergleich mit Rückwärtstrajektorien und Radiosondenprofilen bestärkt. Das Einmischen der Luftmassen in die Grenzschicht beeinflusst dabei die chemische Zusammensetzung in der Vertikalen und wahrscheinlich auch am Boden. Diese experimentelle Studie bestätigt die Relevanz der Einmischungsprozesse aus der freien Troposphäre und die Verwendbarkeit der Korrelationsmethode, um Austausch- und Einmischungsprozesse an dieser Grenzfläche zu bestimmen.

Limitations of Remotely-sensed Aerosol as a Spatial Proxy for Fine Particulate Matter

Recent research highlights the promise of remotely-sensed aerosol optical depth (AOD) as a proxy for ground-level PM2.5. Particular interest lies in the information on spatial heterogeneity potentially provided by AOD, with important application to estimating and monitoring pollution exposure for public health purposes. Given the temporal and spatio-temporal correlations reported between AOD and PM2.5 , it is tempting to interpret the spatial patterns in AOD as reflecting patterns in PM2.5 . Here we find only limited spatial associations of AOD from three satellite retrievals with PM2.5 over the eastern U.S. at the daily and yearly levels in 2004. We then use statistical modeling to show that the patterns in monthly average AOD poorly reflect patterns in PM2.5 because of systematic, spatially-correlated error in AOD as a proxy for PM2.5 . Furthermore, when we include AOD as a predictor of monthly PM2.5 in a statistical prediction model, AOD provides little additional information to improve predictions of PM2.5 when included in a model that already accounts for land use, emission sources, meteorology and regional variability. These results suggest caution in using spatial variation in AOD to stand in for spatial variation in ground-level PM2.5 in epidemiological analyses and indicate that when PM2.5 monitoring is available, careful statistical modeling outperforms the use of AOD.

What are the causes for the spread of GLE parameters deduced from NM data?

Investigations have shown that the analysis results of ground level enhancements (GLEs) based on neutron monitor (NM) data for a selected event can differ considerably depending the procedure used. This may have significant consequences e.g. for the assessment of radiation doses at flight altitudes. The reasons for the spread of the GLE parameters deduced from NM data can be manifold and are at present unclear. They include differences in specific properties of the various analysis procedures (e.g. NM response functions, different ways in taking into account the dynamics of the Earth’s magnetospheric field), different characterisations of the solar particle flux near Earth as well as the specific selection of NM stations used for the analysis. In the present paper we quantitatively investigate this problem for a time interval during the maximum phase of the GLE on 13 December 2006. We present and discuss the changes in the resulting GLE parameters when using different NM response functions, different model representations of the Earth’s magnetospheric field as well as different assumptions for the solar particle spectrum and pitch angle distribution near Earth. The results of the study are expected to yield a basis for the reduction in the spread of the GLE parameters deduced from NM data.

Differences in published characteristics of GLE60 and their consequences on computed radiation dose rates along selected flight paths

The radiation dose rates at flight altitudes can increase by orders of magnitude for a short time during energetic solar cosmic ray events, so called ground level enhancements (GLEs). Especially at high latitudes and flight altitudes, solar energetic particles superposed on galactic cosmic rays may cause radiation that exceeds the maximum allowed dosage limit for the general public. Therefore the determination of the radiation dose rate during GLEs should be as reliable as possible. Radiation dose rates along flight paths are typically determined by computer models that are based on cosmic ray flux and anisotropy parameters derived from neutron monitor and/or satellite measurements. The characteristics of the GLE on 15 April 2001 (GLE60) were determined and published by various authors. In this work we compare these results and investigate the consequences on the computed radiation dose rates along selected flight paths. In addition, we compare the computed radiation dose rates with measurements that were made during GLE60 on board two transatlantic flights.

Meteorological measurements from the Fourcade and Polar Club Glacier, Warszawa Icefield, King George Island, West Antarctica

The South Shetland Islands are located at the northern tip of the AP which is among the fastest warming regions on Earth. The islands are especially vulnerable to climate change due to their exposure to transient low-pressure systems and their maritime climate. Surface air temperature increases (2.5K in 50 years) are concurrent with retreating glacier fronts, an increase in melt areas, ice surface lowering and rapid break-up and disintegration of ice shelves. We have compiled a unique meteorological data set for the King George Island (KGI)/Isla 25 de Mayo, the largest of the South Shetland Islands. It comprises high-temporal resolution and spatially distributed observations of surface air temperature, wind directions and wind velocities, as well as glacier ice temperatures in profile with a fully equipped automatic weather station on the Warszawa Icefield, from November 2010 and ongoing. In combination with two long-term synoptic datasets (40 and 10 years, respectively) and NCEP/NCAR reanalysis data, we have looked at changes in the climatological drivers of the glacial melt processes, and the sensitivity of the inland ice cap with regard to winter melting periods and pressure anomalies. The analysis has revealed, a positive trend of 5K over four decades in minimum surface air temperatures for winter months, clearly exceeding the published annual mean statistics, associated to a decrease in mean monthly winter sea level pressure. This concurs with a positive trend in the Southern Annular Mode (SAM) index, which gives a measure for the strength and extension of the Antarctic vortex. We connect this trend with a higher frequency of low-pressure systems hitting the South Shetland Islands during austral winter, bringing warm and moist air masses from lower latitudes. Due to its exposure to the impact of transient synoptic weather systems, the ice cap of KGI is especially vulnerable to changes during winter glacial mass accumulation period. A revision of seasonal changes in adiabatic air temperature lapse rates and their dependency on exposure and elevation has shown a clear decoupling of atmospheric surface layers between coastal areas and the higher-elevation ice cap, showing the higher sensitivity to free atmospheric flow and synoptic changes. Observed surface air temperature lapse rates show a high variability during winter months (standard deviations up to ±1.0K/100 m), and a distinct spatial variability reflecting the impact of synoptic weather patterns. The observed advective conditions bringing warm, moist air with high temperatures and rain, lead to melt conditions on the ice cap, fixating surface air temperatures to the melting point. This paper assesses the impact of large-scale atmospheric circulation variability and climatic changes on the atmospheric surface layer and glacier mass accumulation of the upper ice cap during winter season for the Warszawa Icefield on KGI.

Modelling Saharan dust transport into the Mediterranean basin with CMAQ

The need for a better quantification of the influence of Saharan dust transport processes on the air quality modelling in the Mediterranean basin led to the formulation of a dust emission module (DEM) integrated into the Air Quality Risk Assessment System for the Iberian Peninsula (SERCA). This paper is focused on the formulation of DEM based on the GOCART aerosol model, along with its integration and execution into the air quality model. It also addresses the testing of the module and its evaluation by contrasting results against satellite products such as MODIS and CALIPSO and ground-level observations of aerosol optical thickness (AOT) and concentration levels of PM10 for different periods in July 2007. DEM was found capable of reproducing the spatial (horizontal and vertical) and temporal profiles of Saharan dust outbreaks into the Mediterranean basin and the Atlantic coast of Africa. Moreover, it was observed that its combination with CMAQ increased the correlation degree between observed and modelled PM10 concentrations at the selected monitoring locations. DEM also enhanced CMAQ capabilities to reproduce observed AOT, although significant underestimations remain. The implementation of CMAQ + DEM succeeded in capturing Saharan dust transport into the Iberian Peninsula, with contributions up to 25 and 14 μg m−3 in 1 h and 24 h average PM10 respectively. The general improvement of total PM10 predictions in Spain are however moderate. The analysis of model performance for the main PM components points out that remaining PM10 underestimation is due to dust local sources missing in the inventories and misrepresentation of organic aerosol processes, which constitutes the main areas for future improvement of CMAQ capabilities to simulate particulate matter within SERCA.

Static Pressure Impact on Aerodynamics of High Speed Railway Tunnels

A pressure wave is generated when a high speed train enters a tunnel. This wave travels along the tunnel back and forth, and is reflected at the irregularities of the tunnel duct (section changes, chimneys and tunnel ends). The pressure changes are associated to these waves can have an effect on passengers if the trains are not suitably sealed or pressurized. The intensity of the waves depends mainly on the train speed, and on the blockage ratio (train-section-to- tunnel-section area ratio). As the intensity of the waves is limited by regulations, and also by the effects on passengers and infrastructures, the sizing of the tunnel section area is largely influenced by the maximum train speed allowed in the tunnel. The aim of this study is to analyse the increase in cost in a tunnel due to the existence of this difference in ground level, and evaluate the increase of construction costs that this elevation might involve.

RANS simulations of wind flow at the Bolund experiment

As part of their development, the predictions of numerical wind flow models must be compared with measurements in order to estimate the uncertainty related to their use. Of course, the most rigorous such comparison is under blind conditions. The following paper includes a detailed description of three different wind flow models, all based on a Reynolds-averaged Navier-Stokes approach and two-equation k-ε closure, that were tested as part of the Bolund blind comparison (itself based on the Bolund experiment which measured the wind around a small coastal island). The models are evaluated in terms of predicted normalized wind speed and turbulent kinetic energy at 2 m and 5 m above ground level for a westerly wind direction. Results show that all models predict the mean velocity reasonably well; however accurate prediction of the turbulent kinetic energy remains achallenge.

Seismic performance case study of bridge pile cap foundation

The purpose of this report is to build a model that represents, as best as possible, the seismic behavior of a pile cap bridge foundation by a nonlinear static (analysis) procedure. It will consist of a reproduction of a specimen already built in the laboratory. This model will carry out a pseudo static lateral and horizontal pushover test that will be applied onto the pile cap until the failure of the structure, the formation of a plastic hinge in the piles due to the horizontal deformation, occurs. The pushover test consists of increasing the horizontal load over the pile cap until the horizontal displacement wanted at the height of the pile cap is reached. The output of this model will be a Skeleton curve that will plot the lateral load (kN) over the displacement (m), so that the maximum movement the pile cap foundation can reach before its failure can be calculated. This failure will be achieved when the load at that specific shift is equal to 85% of the maximum. The pile cap foundation finite element model was based on pile cap built for a laboratory experiment already carried out by the Master student Deming Zhang at Tongji University. Two different pile caps were tested with a difference in height above the ground level. While one has 0:3m, the other rises 0:8m above the ground level. The computer model was calibrated using the experimental results. The pile cap foundation will be programmed in a finite element environment called OpenSees (Open System for Earthquake Engineering Simulation [28]). This environment is a free software developed by Berkeley University specialized, as it name says, in the study of earthquakes and its effects on structures. This specialization is the main reason why it is being used for building this model as it makes it possible to build any finite element model, and perform several analysis in order to get the results wanted. The development of OpenSees is sponsored by the Pacific Earthquake Engineering Research Center through the National Science Foundation engineering and education centers program. OpenSees uses Tcl language to program it, which is a language similar to C++.

Improving the low-wind performance of the AERMOD atmospheric dispersion model for predicting short-range impacts of livestock ammonia emissions.

Short-range impacts to sensitive ecosystems as a result of ammonia emitted by livestock farms are often assessed using atmospheric dispersion modelling systems such as AERMOD. These assessments evaluate mean annual atmospheric concentrations of ammonia and nitrogen deposition rates at the ecosystem location for comparison with ecosystem damage thresholds. However, predictions of mean annual atmospheric concentrations can be dominated by periods of stable night-time conditions, which can contribute significantly to mean concentrations. AERMOD has been demonstrated to overestimate concentrations in certain stable low-wind conditions and so the model could potentially overestimate the short-range impacts of livestock ammonia emissions. This paper tests several modifications to the parameterisation of AERMOD (v12345) that aim to improve model predictions in low-wind conditions. The modifications are first described and then are applied to three pig farm case studies in the USA, Denmark and Spain to assess whether the modifications improve long-term mean ammonia concentration predictions through improved model performance. For these three case studies, most of the modifications tested improved model performance as a result of reducing the long-term mean concentration predictions, with the largest effect for low- or ground-level sources (e.g. slurry lagoons or naturally ventilated housing).

Cálculo de la atracción gravimétrica inducida por el Pabellón de Gravimetría del Centro de Desarrollos Tecnológicos de Yebes (Instituto Geográfico Nacional).

En el presente Trabajo Fin de Grado se modeliza la estructura del Pabellón de Gravimetría del Centro Astronómico de Yebes para así poder determinar su influencia sobre los valores de gravedad observados en el interior del Pabellón. El Pabellón de Gravimetría dispone en su interior de una sala dónde se realizan medidas de gravedad sobre siete pilares de hormigón situados a nivel del suelo. Para poder modelizar la sala de medida se ha realizado un levantamiento topográfico con las especificaciones técnicas de una escala 1:100. Tras la realización del levantamiento se han determinado las coordenadas geográficas del centro de los pilares de medida mediante el cálculo de una radiación, pues es necesario conocer éste dato al realizar medidas relativas de gravedad. Para el cálculo de la influencia que genera la estructura del Pabellón sobre las medidas de gravedad observadas en su interior se han creado una serie de programas en lenguaje Java empleando la fórmula de la atracción gravitatoria que genera un prisma (Nagy, 1969). Una vez se han llevado a cabo las observaciones y los cálculos necesarios se concluye que la influencia de la estructura sobre las medidas de la gravedad observadas en el interior del Pabellón no es de gran magnitud. No obstante esnecesario conocerla y así poder corregir los valores observados. Asimismo, se determina cierta desorientación de los pilares de medida con respecto al norte geográfico. El presente Trabajo Fin de Grado permitirá, entre otros, que el Centro de Desarrollos Tecnológicos de Yebes participe en proyectos de carácter internacional. Abstract: In the current Bachelor Thesis, the structure of the Pavellón de Gravimetría del Centro Astronómico de Yebes is moulded in order to determine its influence on the observed values of gravity inside the Pavilion. The Pabellón de Gravimetría holds in its interior a room where gravity measures are made on seven concrete pillars located on the ground level. In order to be able to mould the room, a topographical survey measurement was made on a 1:100 scale. After concluding the topographical survey measurement the geographical coordinates of the centre of the measurement pillars were determined, due to the necessity to know this data when making relative gravity measures. To calculate the influence that the pavilion structure has on the observed gravity measures in its interior generates, a series of programs in Java language have been created using the formula of the gravitational attraction that generates a prism (Nagy, 1969). Once the observations and the necessary calculations have been carried out, it is concluded that the influences of the structure of the Pavilion on the observed gravity measures inside it are not of a considerable magnitude. Despite that, it is necessary to know this to be able to correct the observed values. Also, certain disorientations of the pillars of measurement with respect to the geographical north is determined. The current Bachelor Thesis will allow, among others, the Centre of Technological Developments of Yebes to get involved in projects of international nature.

Diseño acústico y electroacústico de Waipahu Transit Center en Honolulú, Hawái

El objetivo de este Proyecto Fin de Grado es el diseño de megafonía y PAGA (Public Address /General Alarm) de la estación de tren Waipahu Transit Center en la ciudad de Honolulú, Hawái. Esta estación forma parte de una nueva línea de tren que está en proceso de construcción actualmente llamada Honolulu Rail Transit. Inicialmente la línea de tren constará de 21 estaciones, en las que prácticamente todas están diseñadas como pasos elevados usando como referencia las autopistas que cruzan la isla. Se tiene prevista su fecha de finalización en el año 2019, aunque las primeras estaciones se inaugurarán en 2017. Se trata en primer lugar un estudio acústico del recinto a sonorizar, eligiendo los equipos necesarios: conmutadores, altavoces, amplificadores, procesador, equipo de control y micrófonos. Este primer estudio sirve para obtener una aproximación de equipos necesarios, así como la posible situación de estos dentro de la estación. Tras esto, se procede a la simulación de la estación mediante el programa de simulación acústica y electroacústica EASE 4.4. Para ello, se diseña la estación en un modelo 3D, en el que cada superficie se asocia a su material correspondiente. Para facilitar el diseño y el cómputo de las simulaciones se divide la estación en 3 partes por separado. Cada una corresponde a un nivel de la estación: Ground level, el nivel inferior que contiene la entrada; Concourse Level, pasillo que comunica los dos andenes; y Platform Level, en el que realizarán las paradas los trenes. Una vez realizado el diseño se procede al posicionamiento de altavoces en los diferentes niveles de la estación. Debido al clima existente en la isla, el cual ronda los 20°C a lo largo de todo el año, no es necesaria la instalación de sistemas de aire acondicionado o calefacción, por lo que la estación no está totalmente cerrada. Esto supone un problema al realizar las simulaciones en EASE, ya que al tratarse de un recinto abierto se deberán hallar parámetros como el tiempo de reverberación o el volumen equivalente por otros medios. Para ello, se utilizará el método Ray Tracing, mediante el cual se halla el tiempo de reverberación por la respuesta al impulso de la sala; y a continuación se calcula un volumen equivalente del recinto mediante la fórmula de Eyring. Con estos datos, se puede proceder a calcular los parámetros necesarios: nivel de presión sonora directo, nivel de presión sonora total y STI (Speech Transmission Index). Para obtener este último será necesario ecualizar antes en cada uno de los niveles de la estación. Una vez hechas las simulaciones, se comprueba que el nivel de presión sonora y los valores de inteligibilidad son acordes con los requisitos dados por el cliente. Tras esto, se procede a realizar los bucles de altavoces y el cálculo de amplificadores necesarios. Se estudia la situación de los micrófonos, que servirán para poder variar la potencia emitida por los altavoces dependiendo del nivel de ruido en la estación. Una vez obtenidos todos los equipos necesarios en la estación, se hace el conexionado entre éstos, tanto de una forma simplificada en la que se pueden ver los bucles de altavoces en cada nivel de la estación, como de una forma más detallada en la que se muestran las conexiones entre cada equipo del rack. Finalmente, se realiza el etiquetado de los equipos y un presupuesto estimado con los costes del diseño del sistema PAGA. ABSTRACT. The aim of this Final Degree Project is the design of the PAGA (Public Address / General Alarm) system in the train station Waipahu Transit Center in the city of Honolulu, Hawaii. This station is part of a new rail line that is currently under construction, called Honolulu Rail Transit. Initially, the rail line will have 21 stations, in which almost all are designed elevated using the highways that cross the island as reference. At first, it is treated an acoustic study in the areas to cover, choosing the equipment needed: switches, loudspeakers, amplifiers, DPS, control station and microphones. This first study helps to obtain an approximation of the equipments needed, as well as their placement inside the station. Thereafter, it is proceeded to do the simulation of the station through the acoustics and electroacoustics simulation software EASE 4.4. In order to do that, it is made the 3D design of the station, in which each surface is associated with its material. In order to ease the design and calculation of the simulations, the station has been divided in 3 zones. Each one corresponds with one level of the station: Ground Level, the lower level that has the entrance; Concourse Level, a corridor that links the two platforms; and Platform Level, where the trains will stop. Once the design is made, it is proceeded to place the speakers in the different levels of the station. Due to the weather in the island, which is about 20°C throughout the year, it is not necessary the installation of air conditioning or heating systems, so the station is not totally closed. This cause a problem when making the simulations in EASE, as the project is open, and it will be necessary to calculate parameters like the reverberation time or the equivalent volume by other methods. In order to do that, it will be used the Ray Tracing method, by which the reverberation time is calculated by the impulse response; and then it is calculated the equivalent volume of the area with the Eyring equation. With this information, it can be proceeded to calculate the parameters needed: direct sound pressure level, total sound pressure level and STI (Speech Transmission Index). In order to obtain the STI, it will be needed to equalize before in each of the station’s levels. Once the simulations are done, it is checked that the sound pressure level and the intelligibility values agree with the requirements given by the client. After that, it is proceeded to perform the speaker’s loops and the calculation of the amplifiers needed. It is studied the placement of the microphones, which will help to vary the power emitted by the speakers depending on the background noise level in the station. Once obtained all the necessary equipment in the station, it is done the connection diagram, both a simplified diagram in which there can be seen the speaker’s loops in each level of the station, or a more detailed diagram in which it is shown the wiring between each equipment of the rack. At last, it is done the labeling of the equipments and an estimated budget with the expenses for the PAGA design.