304 resultados para Dunes.
Resumo:
L’objectiu del projecte és la construcció d’unes noves instal•lacions esportives per a la pràctica del futbol a Castellfollit de la Roca degut a la precarietat de l’actual camp de futbol. Inicialment s’ha realitzat un replantejament de la zona retirant una primera capa de restes vegetals per tal de deixar la nova parcel•la neta i llisa. No ha estat necessari anivellar el terreny ja que la parcel•la presentava una topografia gairebé plana, amb un pendent del 0,55%. A continuació s’ha realitzar el moviment de terres per extraure una capa de 0,75 metres de les àrees on es crearan els dos camps de futbol, ja que el terreny d’un camp de futbol és un sòl creat a base de capes de graves i sorres. Tot seguit s’ha dimensionat el drenatge, aquest s’ha realitzat suposant que s’ha d’evacuar la pluja màxima caiguda en dues hores per un període de retorn de 5 anys. A partir d’aquí s’ha decidit que aquesta aigua s’havia d’evacuar per dues vies, per drenatge superficial i per drenatge subterrani
Resumo:
El proceso de integración en Unión Europea se caracteriza por la incorporación de los asuntos de seguridad exterior y defensa, tras el Tratado de Lisboa se enmarcaron en la PCSD. Dicha política por un proceso de integración progresiva, Spillover, ha tenido periodos de reactivación y de letargos.
Resumo:
Conferència sobre la dimensió territorial dels nacionalismes, entenent els nacionalismes com unes ideologies sòcio-polítiques que persegueixen uns objectius determinats a través d’unes pràctiques polítiques determinades o com un conjunt d’expressions ideològiques que tracten de fer reconèixer una comunitat com un tot i que, a més, poden traslluir diverses estructures socials. Es tracta, doncs, el tema “dels nacionalismes”, més que no pas “del nacionalisme”
Resumo:
En la sisena sessió d’investidura de la seva història, el 14 de desembre de 2010, la Universitat de Girona va incorporar al seu Claustre, com a doctors honoris causa, als senyors Ferran Mir i Joan Roca. Han passat a formar part, doncs, d’una llista de notables entre els quals cal destacar filòsofs com Jerome Bruner i Raimon Pannikar, que va cedir la seva biblioteca personal a la UdG i que malauradament va traspassar aquest mes d’agost; historiadors com el pare Miquel Batllori, Eric Hobsbawn i Robert Brian Tate, mort també recentment i el llegat del qual està dipositat a la nostra Universitat; representants del món de la ciència, com la geòloga Carmina Virgili, l’especialista en biomedicina Joan Rodés, el químic Joan Bertran i l’ictiòleg Fred M. Utter; de les ciències socials, com l’economista Jaume Gil Aluja i com l’advocat Miquel Roca, pare de la Constitució; o cantants il·lustres, com és el cas del tenor Jaume Aragall. Després de la cerimònia d’investidura, Engega ha cregut oportú oferir als lectors una aproximació personal a la figura de Ferran Mir i Joan Roca, a partir d’unes entrevistes que ens permeten accedir als continguts del seu pensament, en el camp de la comptabilitat i la gastronomia, respectivament, i a diferents aspectes de la seva activitat professional
Resumo:
Andorra és un microestat situat al bell mig Pirineus, històricament la dinàmica de la població i els seus costums han estat lligats a l’entorn i als recursos que aquest els ofereix. A partir dels anys 50 però, Andorra pateix un increment demogràfic i un canvi en les activitats que s’hi desenvolupen, amb un descens del pes del sector primari i un increment de les activitats del terciari. Aquest fet porta a l'expansió dels nuclis de població i un augment de l’oferta de serveis per a potenciar el turisme i el comerç , augmentant així la pressió sobre el medi, que es veu incrementada per la manca de control i de regulació en l’àmbit de l’ordenament territorial. En els últims anys però, s’han realitzat diferents actuacions que han intentat esmenar aquestes mancances, creant, per exemple, legislació d’ordenació del territori i urbanisme (2001), i els Parcs Naturals de la Vall de Sorteny (1999) i del Comapedrosa (2006). Tot i això, és evident que en l’actualitat existeixen encara moltes mancances que cal resoldre urgentment. Per aquest motiu es fa la la proposta d’una xarxa d’espais naturals protegits a Andorra i la creació d’unes directrius que en facilitin la seva gestió. Situant Andorra a l’alçada d’altres països europeus en matèria de protecció del medi natural, i proporcionant unes bases que permetin la gestió unificada d’aquesta xarxa.
Resumo:
L’origen d’aquest projecte neix en la necessitat de crear un sistema de reserves hoteleres on-line integral i amb connectivitat amb altres sistemes de reserves. S'ha optat pel protocol de comunicació OTA(Open Travel Alliance), es tracta d'un protocol de comunicació XML ideat per empreses del sector turístic dels Estats Units per la necessitat comuna d’unes especificacions tècniques que permetessin la comunicació electrònica de la informació
Resumo:
Una empresa de la indústria farmacèutica vol comercialitzar càpsules elaborades amb plantes medicinals. El procés a seguir per a aconseguir el producte final es realitza mitjançant un molí motoritzat que consta d’unes ganivetes, la funció de les quals és triturar les fulles de les plantes prèviament seleccionades a unes mides realment minúscules, de tal manera que llavors es puguin introduir dins les càpsules. Actualment el procés de trituració es realitza aproximadament a 3.000 rpm i en intentar assolir majors velocitats de treball el capçal de la màquina no les aguanta, cedint un o més dels seus components, patint sobretot l’eix de transmissió i els rodaments, que en ocasions acaben trencant-se. Per a intentar resoldre aquest problema, l’empresa subministradora de maquinària industrial es planteja la viabilitat d’un nou prototipus. La primera mesura que es proposa al client per a solucionar el problema derivat d’aquest augment de la producció és dissenyar un nou capçal del molí motoritzat perquè pugui treballar a velocitats superiors, aproximadament de 18.000 r.p.m, que significaria un canvi total de la transmissió de la màquina
Resumo:
Between 1895 and 1910 Barcelona saw a whole range of social, political and cultural changes due to the increasingly important emergence of the working masses. At the same time, the cinema arrived in Catalonia, becoming very quickly one of the favorite entertainments of the urban laboring population which was about creating a new culture opposed to the modernist and nineteenth-century elite .This is, broadly speaking, the context that serves as a starting point for a study of the role of cinema in shaping a mass audience in Barcelona, an analysis centered on new urban spaces intended for the leisure of the lower classes emerged with the birth of modern Barcelona, especially the “Paral•lel” avenue, whose opening in 1894 made even more apparent the great social tensions and existing inequalities in Barcelona’s society at the end of the century.
Resumo:
The examination of eroding coastal dunes at the prehistoric site of Northton, Harris, has produced the first archaeological evidence of Mesolithic activity in the Western Isles in the form of two midden-related deposits. The first phase of Mesolithic activity is dated to 7060-6650 cal. Bc based on AMS dating of charred hazelnut shells. This discovery appears to validate the frequent pollen-based inferences of Mesolithic impact for the area and, as predicted, allows the Atlantic fringe of Scotland to become part of the European Mesolithic mainstream. A detailed pedological analysis also suggests that these early midden layers may have been amended during the Neolithic period as part of a possible phase of cultivation.
Resumo:
Lacustrine sediments from southeastern Arabia reveal variations in lake level corresponding to changes in the strength and duration of Indian Ocean Monsoon (IOM) summer rainfall and winter cyclonic rainfall. The late glacial/Holocene transition of the region was characterised by the development of mega-linear dunes. These dunes became stabilised and vegetated during the early Holocene and interdunal lakes formed in response to the incursion of the IOM at approximately 8500 cal yr BP with the development of C3 dominated savanna grasslands. The IOM weakened ca. 6000 cal yr BP with the onset of regional aridity, aeolian sedimentation and dune reactivation and accretion. Despite this reduction in precipitation, the take was maintained by winter dominated rainfall. There was a shift to drier adapted C4 grasslands across the dune field. Lake sediment geochemical analyses record precipitation minima at 8200, 5000 and 4200 cal yr BP that coincide with Bond events in the North Atlantic. A number of these events correspond with changes in cultural periods, suggesting that climate was a key mechanism affecting human occupation and exploitation of this region. (c) 2006 University of Washington. All rights reserved.
Resumo:
The ASTER Global Digital Elevation Model (GDEM) has made elevation data at 30 m spatial resolution freely available, enabling reinvestigation of morphometric relationships derived from limited field data using much larger sample sizes. These data are used to analyse a range of morphometric relationships derived for dunes (between dune height, spacing, and equivalent sand thickness) in the Namib Sand Sea, which was chosen because there are a number of extant studies that could be used for comparison with the results. The relative accuracy of GDEM for capturing dune height and shape was tested against multiple individual ASTER DEM scenes and against field surveys, highlighting the smoothing of the dune crest and resultant underestimation of dune height, and the omission of the smallest dunes, because of the 30 m sampling of ASTER DEM products. It is demonstrated that morphometric relationships derived from GDEM data are broadly comparable with relationships derived by previous methods, across a range of different dune types. The data confirm patterns of dune height, spacing and equivalent sand thickness mapped previously in the Namib Sand Sea, but add new detail to these patterns.
Resumo:
The Soil Moisture and Ocean Salinity (SMOS) satellite marks the commencement of dedicated global surface soil moisture missions, and the first mission to make passive microwave observations at L-band. On-orbit calibration is an essential part of the instrument calibration strategy, but on-board beam-filling targets are not practical for such large apertures. Therefore, areas to serve as vicarious calibration targets need to be identified. Such sites can only be identified through field experiments including both in situ and airborne measurements. For this purpose, two field experiments were performed in central Australia. Three areas are studied as follows: 1) Lake Eyre, a typically dry salt lake; 2) Wirrangula Hill, with sparse vegetation and a dense cover of surface rock; and 3) Simpson Desert, characterized by dry sand dunes. Of those sites, only Wirrangula Hill and the Simpson Desert are found to be potentially suitable targets, as they have a spatial variation in brightness temperatures of <4 K under normal conditions. However, some limitations are observed for the Simpson Desert, where a bias of 15 K in vertical and 20 K in horizontal polarization exists between model predictions and observations, suggesting a lack of understanding of the underlying physics in this environment. Subsequent comparison with model predictions indicates a SMOS bias of 5 K in vertical and 11 K in horizontal polarization, and an unbiased root mean square difference of 10 K in both polarizations for Wirrangula Hill. Most importantly, the SMOS observations show that the brightness temperature evolution is dominated by regular seasonal patterns and that precipitation events have only little impact.
Resumo:
The first size-resolved airborne measurements of dust fluxes and the first dust flux measurements from the central Sahara are presented and compared with a parameterization by Kok (2011a). High-frequency measurements of dust size distribution were obtained from 0.16 to 300 µm diameter, and eddy covariance fluxes were derived. This is more than an order of magnitude larger size range than previous flux estimates. Links to surface emission are provided by analysis of particle drift velocities. Number flux is described by a −2 power law between 1 and 144 µm diameter, significantly larger than the 12 µm upper limit suggested by Kok (2011a). For small particles, the deviation from a power law varies with terrain type and the large size cutoff is correlated with atmospheric vertical turbulent kinetic energy, suggesting control by vertical transport rather than emission processes. The measured mass flux mode is in the range 30–100 µm. The turbulent scales important for dust flux are from 0.1 km to 1–10 km. The upper scale increases during the morning as boundary layer depth and eddy size increase. All locations where large dust fluxes were measured had large topographical variations. These features are often linked with highly erodible surface features, such as wadis or dunes. We also hypothesize that upslope flow and flow separation over such features enhance the dust flux by transporting large particles out of the saltation layer. The tendency to locate surface flux measurements in open, flat terrain means these favored dust sources have been neglected in previous studies.
Resumo:
The Namib Sand Sea in southern Africa offers an ideal location in which to consider general questions about the evolution of sand seas, about the fluxes of sand through contemporary dune fields and about the patterns of dune form that are created. This paper aims to provide a concise account of the approaches and techniques that are currently being used and will be used in the future to address these questions. The paper considers the techniques employed to investigate wind climate, the morphometry of the dunes, the internal structure of dune sediments, the age of the dunes and the potential to model dune development
Resumo:
The increased availability of digital elevation models and satellite image data enable testing of morphometric relationships between sand dune variables (dune height, spacing and equivalent sand thickness), which were originally established using limited field survey data. These long-established geomorphological hypotheses can now be tested against very much larger samples than were possible when available data were limited to what could be collected by field surveys alone. This project uses ASTER Global Digital Elevation Model (GDEM) data to compare morphometric relationships between sand dune variables in the southwest Kalahari dunefield to those of the Namib Sand Sea, to test whether the relationships found in an active sand sea (Namib) also hold for the fixed dune system of the nearby southwest Kalahari. The data show significant morphometric differences between the simple linear dunes of the Namib sand sea and the southwest Kalahari; the latter do not show the expected positive relationship between dune height and spacing. The southwest Kalahari dunes show a similar range of dune spacings, but they are less tall, on average, than the Namib sand sea dunes. There is a clear spatial pattern to these morphometric data; the tallest and most closely spaced dunes are towards the southeast of the Kalahari dunefield; and this is where the highest values of equivalent sand thickness result. We consider the possible reasons for the observed differences and highlight the need for more studies comparing sand seas and dunefields from different environmental settings.