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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
441

El karst litoral en el Levante de Mallorca: una aproximación al conocimiento de su morfogénesis y cronología

Ginés Gracia, Joaquín 12 December 2000 (has links)
Se aborda el estudio del karst litoral en la mitad oriental de Mallorca, acometiéndolo desde una perspectiva pluridisciplinar que se ocupa tanto de diferentes aspectos de su modelado epigeo como, sobre todo, de las peculiaridades del rico endokarst existente en el área estudiada. Con respecto a la morfogénesis exokárstica del área, son tratados a lo largo de la presente memoria los siguientes aspectos: el lapiaz litoral, la presencia de calas y sus barrancos asociados y, finalmente, la influencia del paleokarst fini-Mioceno en la morfología de la línea de costa.Los fenómenos subterráneos de Mallorca son estudiados desde un punto de vista genético, describiendo al mismo tiempo las características diferenciales del endokarst en las dos regiones naturales implicadas: las Serres de Llevant y el Migjorn. La atención ha sido focalizada en las numerosas cavidades de la última región kárstica mencionada, la cual destaca por la riqueza y las peculiaridades morfogénicas de sus cavidades hipogeas naturales.Las investigaciones se han centrado en el análisis de las interferencias entre el modelado endokárstico y la dinámica litoral, aportándose datos novedosos sobre un abanico muy variado de materias. Los temas que son abordados abarcan desde aspectos geoquímicos y espeleogenéticos en acuíferos carbonatados litorales, hasta abundantes ejemplos de cuevas mixtas de génesis kárstico-marina. Se presta una particular atención a los rellenos alóctonos de las cavernas costeras, que incluyen tanto materiales detríticos (calcarenitas marinas y/o eólicas) como restos paleontológicos de vertebrados endémicos. Los rellenos autóctonos presentes en las cavidades (espeleotemas, en general) ofrecen especial interés, debido a las grandes posibilidades geocronológicas derivadas de su datación radiométrica. Las interferencias analizadas entre karst y litoral -las cuales han estado controladas en todo momento por la posición del nivel marino- permiten una reconstrucción detallada de la evolución del endokarst a lo largo del Plio-Cuaternario.El mayor interés de los trabajos realizados radica en las valiosas informaciones crono-estratigráficas obtenidas en relación con las oscilaciones pleistocénicas del nivel marino. En concreto, el estudio de los espeleotemas freáticos ha mostrado que éstos constituyen un excelente registro de la historia del nivel del Mediterráneo, durante el Pleistoceno Medio y Superior y el Holoceno. Conviene resaltar los novedosos datos aportados por aquellos espeleotemas freáticos que han sido recolectados por debajo de la presente cota ±0 metros; estas cristalizaciones nos documentan, con gran detalle, las pulsaciones regresivas experimentadas por el nivel marino, las cuales eran bastante desconocidas hasta el momento. Este tipo de depósitos secundarios propios de las cuevas kársticas litorales han sido estudiados mediante diversas técnicas (dataciones radiométricas Th/U, mediciones de ESR, microscopía óptica y electrónica, análisis de isótopos estables...) con vistas a la obtención de datos cronológicos, paleoclimáticos, mineralógicos y cristalográficos precisos.De particular relevancia son las curvas eustáticas propuestas para los últimos 300 ka, en el Mediterráneo occidental, las cuales presentan un detalle fuera de lo común en el rango de edad comprendido entre 150 y 60 ka BP. Centrando nuestra atención en el último evento interglacial (estadio isotópico 5) es posible distinguir cuatro picos transgresivos, situados entre 130 y 80 ka BP, separados por tres pulsaciones frías que produjeron descensos bruscos del nivel del Mediterráneo, de más de 20 metros de amplitud. Las tasas deducidas de ascenso y/o descenso del nivel marino son del orden de 4 metros/ka, poniendo de manifiesto las importantes crisis climáticas acontecidas durante el Pleistoceno Superior. / This thesis deals with the study of littoral karst in the eastern half of Mallorca island, by means of a cross-disciplinary approach that takes into account both the different aspects of its surface modelling (littoral karren, coves and associated gullies, paleokarst features) and the singularities of the rich endokarst existing in this area. The subterranean phenomena in the island are studied from a genetical point of view, describing at the same time the differential characteristics of endokarst in the two natural regions involved: Serres de Llevant and, particularly, the Migjorn area. Our investigations have been specially addressed to analyze the interferences between endokarstic modelling and littoral dynamics. The topics that are discussed cover from geochemical and speleogenetical aspects in coastal carbonate aquifers, to abundant examples of mixed cavities which are karstic-marine in origin. Particular attention is paid to the alochtonous infillings existing in coastal caves, that include both detritic materials (marine and/or eolian calcarenites) and paleontological remains of endemic vertebrates.Specifically, the study of phreatic speleothems has shown that these deposits are an excellent record of Mediterranean sea-level history, during Middle and Upper Pleistocene and Holocene. Abundant data supplied by phreatic speleothems collected below the present-day ±0 metres must be thrown into relief; these crystallizations document us -with a great detail- the regressive pulsations experienced by the sea-level. This deposits has been studied by means of several techniques (radiometric Th/U datings, ESR measurements, optical and electronic microscopy, X-ray diffraction, stable isotope analysis.) in order to obtain precise chronological, paleoclimatological, mineralogical and crystallographical data.Eustatic curves proposed for the last 300 ka in the western Mediterranean are significant. Centering our attention in the last interglacial event (isotopical stage 5) four transgressive peaks are distinguished, situated between 130 and 80 ka BP, separated by three cold pulsations that produced abrupt Mediterranean sea lowerings, about 20 metres in amplitude. The deduced mean rates of sea-level rise and/or lowering are in the order of 4 metres/ka.
442

Sources and processes affecting levels and composition of atmospheric particulate matter in the Western Mediterranean

Rodríguez González, Sergio 03 December 2002 (has links)
This study is focused on the identification of the sources and processes affecting levels and composition of PM10 and PM2.5 from air quality monitoring networks in Eastern Spain. This is a multidisciplinary study. Time series of TSP and PM10 recorded from 1996 to 2000 are interpreted to assess the role of local, regional and distant sources in PM levels in this region. To this is end, the influence of the meteorology on PM levels recorded at nineteen rural, urban and industrial monitoring stations is studied by means of synoptic charts, back-trajectories and local meteorological variables. The impact of African dust transport on PM levels is investigated by means of simulations in the SKIRON forecast system and by TOMS satellite observations. Moreover, a chemical characterisation of PM10, PM2.5 and TSP size segregated fractions and a daily PM10 and PM2.5 source apportionment by two receptor modelling techniques are performed. For this purpose, 24-hour samples of PM10 were collected for 16, 12 and 5 months at rural, urban and industrial sites, respectively. PM2.5 was sampled at the urban site simultaneously with PM10. The results showed that day-to-day variations in PM levels are highly influenced by the meteorology. From March to October, PM levels at rural, urban and industrial sites vary as a function of the concatenation of Atlantic air mass advections (Atlantic episodes with low PM levels) and regional circulations (Regional events with high PM and O3 levels) which induce the PM transport from urban/industrial to rural sites and the ageing of polluted air masses in the Western Mediterranean. From November to February low PM levels are recorded at rural sites, and variations in PM levels at urban/industrial sites are governed by the successive occurrence of Atlantic episodes and Local urban/industrial pollution events (with high PM, NOx and CO levels). The African dust events mainly occur from January to October and induce very high PM levels in all sites. As a result of the frequency and intensity of the Regional episodes, PM levels at rural sites undergo a seasonal evolution with a summer maximum. The difference between PM levels at urban and rural sites presents an autumn-winter maximum owing to the occurrence of intensive Local urban pollution events. The meteorological context in which the aforementioned episodes occur is discussed, with special emphasis on the synoptic scenarios giving rise to the African dust outbreaks in the different seasons. Levels of PM components at the different study sites were compared. The seasonal evolution and the grain size distribution of these components was studied and the form of occurrence was determined. The chemical characterisation shows that high levels of natural mineral dust components (e.g. Al, Fe, Mg, Ti, Sr, Ca) are simultaneously recorded in PM10 and PM2.5 at all sites during African episodes. Other interesting findings are: 1) a marked seasonal evolution of nitrate levels and grain size distribution due to the occurrence of ammonium-nitrate in autumn-winter, 2) an excess of Na with respect to the Na/Cl marine ratio in summer owing to reactions of acids with sea salt, and 3) high background levels of ammonium-sulphate in summer. Moreover, the levels of elemental, organic and mineral carbon were determined. At the rural site, the PM10 annual mean reaches 22µg/m3, the main contributions being secondary particles from industrial emissions (27% of PM10), vehicle exhausts (14-23%), natural mineral dust (23%) and sea spray (5-9%). At the urban kerbside station, the PM10 annual mean reaches 49µg/m3, the main contributions being vehicle exhausts (35-45% of PM10), secondary particles from industrial emissions (24-31%), natural + road dust (25%) and sea spray (4-6%). At the urban kerbside station, the PM2.5 annual mean reaches 34µg/m3, the main contributions being vehicle exhausts (41-53% of PM2.5), secondary particles from industrial emissions (29-35%) and mineral dust (9-11%). These results have important implications for the implementation of the PM10 EU standards. The natural load in ambient PM10 levels in Eastern Spain accounts for 30-40% of the 2010 EU annual PM10 limit value (20µg/m3). In this region it will not be easy to meet this limit value given that the annual PM10 levels are in the range 17-20µg/m3 at rural, 30-45µg/m3 at urban and 45-60µg/m3 at industrial sites. The high background levels of PM10 in this region are favoured by the specific orographic and meteorological context of the Mediterranean and by the high load of mineral dust caused by the soil re-suspension and the frequent occurrence of African dust events. At rural sites, 2-5 exceedances of the EU daily PM10 limit value (50µg/m3) are recorded every year during African dust outbreaks. On average, 15 African induced and 40-80 non-African induced exceedances of the EU daily PM10 limit value are recorded every year at the urban kerbside stations. The parameter selected for PM monitoring is a key factor. Most of the PM species resulting from combustion and vehicle exhaust emissions have a fine size distribution (<2.5µm), with exception of nitrate in summer, whereas sea spray and mineral dust present a coarse size distribution. The interference of African dust in the PM monitoring is significantly reduced when PM2.5 instead of PM10 is monitored. Natural mineral dust concentrations during African episodes are in the ranges 20-30µg/m3 in PM10 and 10-15µg/m3 in PM2.5. However, PM2.5 is not a suitable parameter for PM monitoring in all environments. The selection of PM10 or PM2.5 should be conditioned by the type of anthropogenic activity. At urban sites, PM2.5 contains mainly vehicle exhaust products, whereas the road traffic dust principally occurs in the 2.5-10µm fraction. PM2.5 is not a suitable parameter for monitoring some industrial activities (e.g. ceramics, cement production or mining) with primary PM emissions in the 2.5-10µm range.
443

Dynamics And Evolution Of European Union&#039 / s Middle East Policy

Dersan, Duygu 01 July 2006 (has links) (PDF)
This thesis aims to analyze the development of the collective policies of the European Union towards the Middle East by focusing on the reasons behind the formulation of these policies, and the degree of success, failure and prospects of these policies. The general success of the European Community in the 1970s created a desire for European states to form a coordinated European foreign policy. Since the 1970s, the Community started to show willingness to shape international events and to strengthen its international role. The Middle East was one of the leading regions to which the Community turned in the early 1970s, an area, which, for historical and geographical reasons, is of vital interest to it. EU has been becoming a coherent and strategic actor in the Middle East since the 1990s. It has secured an important presence in the Middle East Peace Process and it has further strengthened its role in the Middle East through the adoption of a common, comprehensive regional strategy called the Euro-Mediterranean Partnership and developed it with the initiation of the European Neighborhood Policy. However, the European Union&rsquo / s presence is still limited due to its institutional weaknesses, the lack of political unity among its member states, lack of political instruments and military capabilities.
444

Wind And Wind Wave Climate For Turkish Coast And Application To Aegean And Mediterrenean Sea

Aldogan, Serhan 01 July 2008 (has links) (PDF)
The wind waves have significant effects on small craft and fisheries. Therefore, wind wave climate has an important role in the design and operation of fishing harbors and harbors for small craft. The purpose of this study is to identify the wind wave climate along the eastern part of the Mediterranean Sea coastline of T&uuml / rkiye. For this purpose, wind wave data for a certain period is obtained from ECMWF for the analysis. Moreover, the data will be analyzed for locations selected along the Turkish coast using a special software developed for this thesis study. For every location, the wind wave roses, significant wind wave height versus mean period of primary wind relations, extreme probability distribution, and log-linear cumulative probability distributions will be presented. By the help of software developed, it will be possible to analyse any coordinate using ECMWF data.
445

Database Development For Tsunami Warning System In Mediterranean Basin By Tsunami Modeling

Onat, Yaprak 01 June 2011 (has links) (PDF)
Wider awareness, proper preparedness and effective mitigation strategies need better understanding of tsunamis and tsunami hazard assessment. Tsunami assessment study covers the exchange and enhancement of available earthquake and tsunami data, development of bathymetric and topographic data in sufficient resolution, selection of possible or credible tsunami scenarios, selection and application of the valid and verified numerical tools for tsunami generation, propagation, coastal amplification, inundation and visualization. From this point of view, this thesis deals with all these components of tsunami hazards assessment. The database of 38 different seismic sources is generated and applied to Eastern Mediterranean Basin by using numerical code called NAMI DANCE. Furthermore, the simulation results are compared and discussed. In the thesis, the difficulties in defining seismic source parameters, the effect of dip and rake (slip) angle on seismic generated tsunamis are evaluated. Moreover, the performance of the numerical code, the accuracy of results, the efficiency of the numerical methods in the application to Mediterranean Basin Tsunamis and the comparisons of simulations in nested domains for Bodrum, Kas and Iskenderun are given as case studies. According to the study, north-west and south-west of Turkey may have tsunami risk more than other regions. The maximum wave amplitudes, which may be expected to occur near the shore, are found more than 4 m. However, maximum positive wave amplitude observed in history is approximately 8 m. The arrival time of first wave to hit the coasts vary in a range of 15 to 60 minutes depending on the closeness of the location to the sources&rsquo / epicenter.
446

Lithic Technology and Obsidian Exchange Networks in Bronze Age Sardinia, Italy (ca. 1600-850 B.C.)

Freund, Kyle P. 01 April 2010 (has links)
The Sardinian Bronze Age (Nuragic period) and the factors which created and maintained an island-wide identity as seen through the presence of its distinctive nuraghi have received considerable attention; however the amount of research directly related to the stone tools of the era has been relatively limited despite the wealth of knowledge it is capable of yielding. This thesis hopes to contribute to Sardinian archaeology through the study of ancient technology, specifically obsidian lithic technology, by combining typological information with source data gleaned from the use of X-ray fluorescence spectrometry (XRF). These data are integrated with statistical analyses breaking down the spatial distribution of nuraghi across the island through the use of distance-based methods, including k-means and kernel density analyses, which create a more comprehensive understanding of the island-wide political and social structure. This research will test the hypothesis that changes in the acquisition of obsidian raw materials were coupled with corresponding changes in how the obsidian was used. The results provide precedence for future work in Sardinia and create a model for integrating two types of analyses, sourcing and typological. By combining these results, it is possible to investigate how obsidian influenced the ancient economy as well as assess its cultural significance for people of the past.
447

The Poetics of Love in Prosimetra across the Medieval Mediterranean

Levy, Isabelle Charlotte January 2013 (has links)
Written as prose began to garner attention in literary cultures that had long privileged poetic composition, prosimetra offer a unique perspective on what authors in eleventh-century al-Andalus and thirteenth- and fourteenth-century Spain and Italy singled out as the special capabilities of poetry. Further, as the only shared theme across mixed-form texts in Arabic, Hebrew, Italian, and Spanish, love acts as a go-between across these varied literary traditions.
448

Απορρίμματα και εκτίμηση θαλάσσιων και χερσαίων πηγών ρύπανσης στις ελληνικές ακτές

Μοιρώτσου, Αναστασία, Παπαμιχαλοπούλου, Κωνσταντίνα 01 April 2014 (has links)
Στα πλαίσια της παρούσας εργασίας εκτιμήθηκαν οι συστάσεις παράκτιων απορριμμάτων, καθώς και πηγές ρύπανσης των θαλάσσιων και χερσαίων απορριμμάτων στις ελληνικές ακτές. Η μη κυβερνητική οργάνωση «Δίκτυο ΜΕΣΟΓΕΙΟΣ SOS» βοήθησε στην καταγραφή των απορριμμάτων με τη συμβολή εθελοντών. Οι εθελοντές συμπληρώνοντας ειδικό φύλλο καταγραφής κατέγραψαν τα απορρίμματα τόσο ποσοτικά, όσο και ποιοτικά. Στα δεδομένα που συλλέχθηκαν εφαρμόστηκε πολυδιάστατη στατιστική ανάλυση από την οποία αντλήθηκαν πληροφορίες, βάσει των οποίων κατηγοριοποιήσαμε τις ελληνικές ακτές ανάλογα με τις πηγές ρύπανσης τους, τόσο για το έτος 2010, όσο και για το επόμενο έτος 2011. / As part of this study evaluated the recommendations coastal litter and pollution sources of marine litter on land and Greek coasts. The non-governmental organization "Network MEDITERRANEAN SOS» helped in the recording of waste with the help of volunteers. Volunteers completing specific worksheet registered waste both quantitatively and qualitatively. Among the data collected was applied multidimensional statistical analysis from which information was drawn, whereby the Greek coast categorized depending on the sources of pollution, both for 2010 and for next year 2011.
449

Σύσταση απορριμμάτων & εκτίμηση της συμβολής των πηγών απορριμμάτων σε 80 ελληνικές ακτές

Κορδέλλα, Σταυρούλα 18 March 2009 (has links)
Στην παρούσα εργασία έγινε εκτίμηση της σύσταση παράκτιων απορριμμάτων και της συμβολής χερσαίων και θαλάσσιων πηγών ρύπανσης σε 80 ακτές από όλη την Ελλάδα. Η συλλογή των δεδομένων έγινε με τη συμμετοχή εθελοντών, οι οποίοι κατέγραψαν ποσοτική (εκτίμηση ποσοστών των υλικών των απορριμμάτων) και ποιοτική πληροφορία (σχετικά με τις πηγές ρύπανσης) στην οποία έγινε παραμετροποίηση. Στον πίνακα δεδομένων που προέκυψε έγινε πολυδιάστατη στατιστική ανάλυση, όπου σύμφωνα με τα αποτελέσματά της, οι ακτές στην Ελλάδα διακρίνονται σαφώς με βάση τις πηγές ρύπανσης τους, ενώ επίσης χωρίζονται σε δύο στατιστικά σημαντικές ομάδες, σύμφωνα με τις πηγές και τα υλικά των απορριμμάτων που υπάρχουν σε αυτές. Το υλικό που βρέθηκε να κυριαρχεί στις ελληνικές ακτές είναι το πλαστικό (42,6% - 50,6%). / In the present study, the composition of beach litter and the contribution of land based and marine based litter - sources, were estimated for 80 beaches from all over Greece. The data was collected with the contribution of volunteers, who gathered quantitative (estimates on percentages of litter material) and qualitative information (on the beach litter sources). The results of multivariate statistical techniques, that were applied on the data matrix, which was formed after the parametrization of the qualitative data, showed that Greek beaches may be distinguished in to statistically important groups, according to the sources and material of beach - stranded litter. Plastic is the dominant material in greek beaches (42.6% - 50.6%).
450

Political, Economic, Social, and Health-related Correlates of HIV/AIDS Prevalence in the Eastern Mediterranean Region of WHO

Elimam, Dena 05 December 2008 (has links)
HIV/AIDS remains one of the most challenging public health problems, especially as the number of people living with the disease increased to over 33 million in 2007 while deaths increased to 2.0 million. The progression of HIV/AIDS is often linked to multiple levels of influence such as individual, political, economic, health and social factors. There is little known about the influence of some of these factors on the prevalence of HIV/AIDS in the countries of the Eastern Mediterranean Region (EMR) of the World Health Organization. Using data from EMR countries, this study analyzed the progression of HIV/AIDS from 2003 to 2005, and examined the correlation between a number of political, economic, social, and health-related indicators with three HIV/AIDS outcome measures (HIV/AIDS estimated rates, HIV/AIDS death rates, and antiretroviral therapy coverage rates) for the year 2005. Bivariate correlation analyses showed several political, economic, social, and health-related variables to be significantly associated with antiretroviral therapy coverage rates. Immunization rate was the only variable significantly associated with the estimated HIV/AIDS rates; while no significant associations were identified with the HIV/AIDS death rates. The results of this study suggest that progression of the disease and treatment accessibility may be influenced by the political, economic, social, and health situations in EMR countries.

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