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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.
51

Logistické prístupy k rozvoju regionálnej turistiky v Turecku / Logistical Approaches to the Development of Regional Tourism in Turkey

Patriková, Eva January 2012 (has links)
Tourism in Turkey has passed a certain developmental stage, but today increases an opportunity to broach a new stage in the development of alternative types of tourism. Together with appropriate development of transport infrastructure, may be developed the other less visited regions of Turkey. The government of Turkey is good aware of this fact and concerned departments approach to this challenge with proper importance. Thus, it could be expected a positive result.
52

From Russia’s Orient To Russia’s Riviera: Reimagining The Black Sea Coast/Caucasus from Romantic Literature to Early Tourist Guidebooks

Lywood, William George January 2009 (has links)
No description available.
53

Vegetation, climate and environmental dynamics of the Black Sea/Northern Anatolian region during the last 134 ka obtained from palynological analysis

Shumilovskikh, Lyudmila 06 March 2013 (has links)
No description available.
54

Ukrajinská geopolitika ve 20. a 21. století. / Ukrainian geopolitics in the 20th and 21st centuries

Hliba, Ihor January 2022 (has links)
Knowledge of a country's national geopolitics is the key to understanding the state in all its political forms. Therefore, this thesis is devoted to the Ukrainian geopolitics of the 20th - 21st century. In it we described the main concepts and opinions of Ukrainian geopoliticians. Our goal was to learn more about the theoretical foundations of Ukrainian geopolitics as it was in the 20th century and to see its further development in the 21st century. We tried to describe as fully as possible the views of Ukrainian geopoliticians and note the peculiarities of their thinking. We also analysed possible factors influencing the geopolitical vision of Ukrainians in the 20th and 21st centuries. This thesis is divided into three major parts and conclusions. The first chapter presents the main geopolitical concepts that emerged in the first half of the 20th century and their classification. In the second chapter, we focused more on those concepts that concerned the Black Sea region. In the third chapter, we presented the main and interesting concepts of Ukrainian geopolitics of the 21st century. Conclusions are an important analytical element of our work
55

Paleoenvironmental changes in the Black Sea region during the last 26,000 years : a multi-proxy study of lacustrine sediments from the western Black Sea

Kwiecien, Olga January 2008 (has links)
Paleoenvironmental records provide ample information on the Late Quaternary climatic evolution. Due to the great diversity of continental mid-latitude environments the synthetic picture of the past mid-latitudinal climate changes is, however, far from being complete. Owing to its significant size and landlocked setting the Black Sea constitutes a perfect location to study patterns and mechanisms of climate change along the continental interior of Central and Eastern Europe and Asia Minor. Presently, the southern drainage area of the Black Sea is characterized by a Mediterranean-type climate while the northern drainage is under the influence of Central and Northern European climate. During the Last Glacial a decrease in the global sea level disconnected the Black Sea from the Mediterranean Sea transforming it into a giant closed lake. At that time atmospheric precipitation and related with it river run-off were the most important factors driving sediment supply and water chemistry of the Black ‘Lake’. Therefore studying properties of the Black Sea sediments provides important information on the interactions and development of the Mediterranean and Central and North European climate in the past. One significant outcome of my thesis is an improved chronostraphigraphical framework for the glacial lacustrine unit of the Black Sea sediment cores, which allowed to refine the environmental history of the Black Sea region and enabled a reliable correlation with data from other marine and terrestrial archives. Data gathered along a N-S transect presented on a common time scale revealed coherent changes in the basin and its surrounding. During the glacial, the southward-shifted Polar Front reduced moisture transport to the northern drainage of the Black Sea and let the southern drainage become dominant in freshwater and sediment supply into the basin. Changes in NW Anatolian precipitation reconstructed from the variability of the terrigenous input imply that during the glacial the regional rainfall variability was strongly influenced by Mediterranean sea surface temperatures and decreased in response to the cooling associated with the North Atlantic Heinrich Events H1 and H2. In contrast to regional precipitation changes, the hydrological properties of the Black Sea remained relatively stable under full glacial conditions. First significant modification in the freshwater/sediment sources reconstructed from changes in the sediment composition, lithology, and 18O of ostracods took place at around 16.4 cal ka BP, simultaneous to the early deglacial northward retreat of the oceanic and atmospheric polar fronts. Meltwater pulses, most probably derived from the disintegrating European ice sheets, changed the isotopic composition of the Black Sea and increased the supply from northern sediment sources. While these changes signalized a mitigation of the Northern European and Mediterranean climate, a decisive increase in local temperature was indicated only later at the transition from the Oldest Dryas to the Bølling around 14.6 cal ka BP. At that time the warming of the Black Sea surface initiated massive phytoplankton blooms, which in turn, induced the precipitation of inorganic carbonates. This biologically triggered process significantly changed the water chemistry and was recorded by simultaneous shifts in the elemental composition of ostracod shells and in the isotopic composition of the inorganically-precipitated carbonates. Starting with the B/A warming and continuing through the YD cold interval and the Early Holocene warming, the Black Sea temperature signal corresponds to the precipitation and temperature changes recorded in the wider Mediterranean region. Early Holocene conditions, similar to those of the Bølling/Allerød, were punctured by the marine inflow from the Mediterranean at ~ 9.3 cal ka BP, which terminated the lacustrine phase of the Black Sea and had a substantial impact on the chemical and physical properties of its water. / Aus Paläoumweltdaten lassen sich detaillierte Informationen über die spätquartäre Klimaentwicklung gewinnen. Für die kontinentalen mittleren Breiten ist das Gesamtbild der Klimaänderungen während dieses Zeitraumes aufgrund seiner Vielfältigkeit allerdings noch immer unvollständig. Eine ideale Loka-tion, das Muster und die Mechanismen der Klimaänderungen in Osteuropa und Kleinasien zu untersu-chen, ist das Schwarze Meer mit seiner bedeutenden Größe und seiner kontinentalen Lage. Gegenwärtig ist das südliche Einzugsgebiet des Schwarzen Meeres durch ein mediterranes Klima ge-prägt, während die nördlichen Regionen von zentral- bzw. nordeuropäischem Klima beeinflusst werden. Als im letzten Glazial der Meeresspiegel so stark sank, dass das Schwarze Meer vom Mittelmeer abge-trennt und zu einem großen, abflusslosen See wurde, waren der atmosphärische Niederschlag und der damit verbundene Abfluss die wesentlichen Steuerfaktoren für Sedimenteintrag und Wasserchemie des Schwarzen „Sees“. Deshalb liefert die Untersuchung der Sedimente des Schwarzen Meeres wichtige Informationen über die früheren Zusammenhänge sowie die Entwicklung von mediterranem und zentral- bzw. nordeuropäischem Klima. Das bedeutsamste Ergebnis meiner Doktorarbeit ist ein verbessertes Altersmodell für Sedimentkerne aus dem westlichen Schwarzen Meer; dieses erlaubt eine genauere Rekonstruktion der Entwicklungsge-schichte dieses Binnenmeeres und seiner Umgebung und ermöglicht einen fundierten Vergleich mit an-deren marinen und terrestrischen Archiven. Daten, die entlang eines N-S Transektes im westlichen Be-reich des Schwarzen Meeres erfasst wurden und auf einer gemeinsamen Zeitskala dargestellt werden, lassen die folgenden zusammenhängenden Entwicklungen im Becken und seiner Umgebung erkennen: Während des Glazials war der Feuchtigkeitstransport zum nördlichen Einzugsgebiet des Schwarzen Meeres aufgrund der südwärts verlagerten Polarfront vermindert, so dass Süßwasser und Sedimente vor-rangig aus dem südlichen Einzugsgebiet in das Becken gelangten. Die Rekonstruktion von Nieder-schlagsänderungen mit Hilfe von Schwankungen des terrigenen Eintrags zeigt, dass der regionale Nie-derschlag im Glazial stark von den Wasseroberflächentemperaturen des Mittelmeeres beeinflusst wurde und als Folge der Abkühlung während der nordatlantischen Heinrich-Ereignisse H1 und H2 abnahm. Im Gegensatz dazu blieb das Schwarze Meer während des Hochglazials hydrologisch relativ stabil. Die Sedimentzusammensetzung, Lithologie und δ18O-Werte von Ostracoden zeigen, dass erste signifi-kante Änderungen im Frischwasser- und Sedimenteintrag zeitgleich mit dem frühglazialen nordwärtigen Rückzug der ozeanischen und atmosphärischen Polarfronten um 16.4 cal ka BP auftraten. Der Schmelz-wassereintrag abschmelzender europäischer Eisflächen veränderte die Isotopenzusammensetzung des Wassers und erhöhte die Sedimentzufuhr aus den nördlichen Quellen. Während diese Änderungen auf ein bereits milderes Klima in Nordeuropa und im Mittelmeerraum hin-deuten, zeigt sich ein Anstieg der lokalen Temperaturen erst während des Übergangs von der Älteren Dryas zum Bølling/Allerød um etwa 14.6 cal. ka BP. Zu diesem Zeitpunkt führte ein wahrscheinlicher Anstieg der Wasseroberflächentemperaturen im Schwarzen Meer zu einem massiven Phytoplankton-wachstum, welcher die Ausfällung anorganischen Karbonats zur Folge hatte. Dieser biologisch ausgelös-te Prozess veränderte maßgeblich die Wasserchemie und spiegelt sich in simultanen Veränderungen der Elementzusammensetzung von Ostracoden und der Isotopenzusammensetzung von anorganisch ausge-fälltem Karbonat wieder. Beginnend mit dem Bølling/Allerød, durch die Jüngere Dryas Kälteperiode und die frühholozäne Erwärmung hindurch, deckt sich das Temperatursignal des Schwarzen Meeres mit den Niederschlags- und Temperaturänderungen des weiteren Mittelmeerraumes. Das Frühholozän war, ähnlich wie das Bølling/Allerød, durch das Einströmen salzhaltigen Meerwassers aus dem Mittelmeer gekennzeichnet (~9.5 cal. ka BP), welches die lakustrine Phase des Schwarzen Mee-res beendete und einen erheblichen Einfluss auf seine chemischen und physikalischen Wassereigen-schaften ausübte.
56

Investigation Of The Interaction Of Co2 And Ch4 Hydrate For The Determination Of Feasibility Of Co2 Storage In The Black Sea Sediments

Ors, Oytun 01 September 2012 (has links) (PDF)
Recently, carbon dioxide injection into deep sea sediments has become one of the carbon dioxide mitigation methods since carbon dioxide hydrates are stable at the prevailing pressure and temperature conditions. The Black Sea, which is one of the major identified natural methane hydrate regions of the world, can be a good candidate for carbon dioxide storage in hydrate form. Injected carbon dioxide under the methane hydrate stability region will be in contact with methane hydrate which should be analyzed thoroughly in order to increase our understanding on the gaseous carbon dioxide and methane hydrate interaction. For the storage of huge amounts of CO2, geological structure must contain an impermeable barrier. In general such a barrier may consist of clay or salt. In this study, sealing efficiency of methane hydrate and long term fate of the CO2 disposal under the methane hydrate zone is investigated. In order to determine the interaction of CO2 and CH4 hydrate and the sealing efficiency of CH4 hydrate, experimental setup is prepared and various tests are performed including the CH4 hydrate formation in both bulk conditions and within sand particles, measurement of the permeability of unconsolidated sand particles that includes 30% and 50% methane hydrate saturations and injection of CO2 into the CH4 hydrate. Results of the experiments indicate that, presence of hydrate sharply decreases the permeability of the unconsolidated sand system and systems with hydrate saturations greater than 50% may act as an impermeable layer. Also, CO2-CH4 swap within the hydrate cages is observed at different experimental conditions. As a result of this study, it can be concluded that methane hydrate stability region in deep sea sediments would be a good alternative for the safe storage of CO2. Therefore, methane hydrate stability region in the Black Sea sediments can be considered for the disposal of CO2.
57

Hydrate Formation Conditions Of Methane Hydrogen Sulfide Mixtures

Bulbul, Sevtac 01 February 2007 (has links) (PDF)
The objective of this study is to determine hydrate formation conditions of methane- hydrogen sulfide mixtures. During the study, an experimental work is carried out by using a system that contains a high-pressure hydrate formation cell and pressure-temperature data is recorded in each experiment. Different H2S concentrations and both brine and distilled water are used in the experiments and the Black Sea conditions, which are suitable for methane-hydrogen sulfide hydrate formation are examined. Considering the pressure-temperature data obtained, hydrate equilibrium conditions are determined as well as the number of moles of free gas in the hydrate formation cell. The change in the number of moles of free gas in the hydrate formation cell with respect to time is considered as a way of determining rate of hydrate formation. Effects of H2S concentration and salinity on hydrate formation conditions of methane-hydrogen sulfide mixtures are also studied. It is observed that an increase in the salinity shifts the methane-hydrogen sulfide hydrate equilibrium condition to lower equilibrium temperatures at a given pressure. On the other hand, with an increase in H2S concentration the methane hydrogen sulfide hydrate formation conditions reach higher equilibrium temperature values at a given pressure. After the study, it can be also concluded that the Black Sea has suitable conditions for hydrate formation of methane hydrogen sulfide mixtures, considering the results of the experiments.
58

Review Of Natural Gas Discovery And Production From Conventional Resources In Turkey

Keskin, Hakan 01 May 2007 (has links) (PDF)
Oil and natural gas are the most strategic raw materials to meet the expanding energy requirement in today&rsquo / s world. They have great impact on issues such as economy, national security, development, competition, and political consistency. Being a developing country, Turkey&rsquo / s natural gas requirement is increasing rapidly. However, the production is far from covering the demand. Recent assumptions point out that natural gas demand of Turkey will reach 44 billion cubic meters in 2010 with a financial burden of 10 billion $ to the national economy. Therefore Turkey requires meeting natural gas demand by using its own conventional natural gas resources. The geological researches and global data encourage Turkey to drill more exploration wells in offshore side of Western Black Sea .In early 2007, the production will be started in Western Black Sea Region with 1.42 million cubic meter gas per day. Moreover, further exploration and production activities in the region are still continuing in order to increase the production. In this thesis, issues such as importance of the natural gas for Turkey and the world, Turkey&rsquo / s present energy situation and natural gas supply and demand scenarios for Turkey have been investigated. The possible impact of natural gas exploration and production in Black Sea region on Turkey&rsquo / s economy in near future has been emphasized. An extensive literature survey using related printed and unprinted media has been performed in order to collect the necessary data and information.
59

Wind And Wind Wave Climate Research Along The Southern Part Of Black Sea

Caban, Seckin 01 July 2007 (has links) (PDF)
Winds and wind wave climate are two important phenomena for Black Sea basin. Wind wave climate has an important role on design of coastal structures and naval transportation. Despite this fact the wind wave climate is not well known for the Turkish coasts because of limited studies on this subject. The purpose of the present study was to further understand wind and wind wave climate along the Black Sea coastline of T&uuml / rkiye. For this purpose wind and wind wave data for every 65 months is obtained from ECMWF for and analyzed for 12 locations situated along Black Sea coast of Turkey. For every location the wind [Berk&uuml / n,2007] and wind wave roses, significant wind wave height vs. Mean wave period relations, extreme probability distribution and log-linear cumulative probability distribution are presented. Also a comparison with previous studies is given for better understanding the wind and wave climate better.
60

Spectral Characteristics Of Wind Waves In The Eastern Black Sea

Yilmaz, Nihal 01 July 2007 (has links) (PDF)
Wind waves are highly complex, random phenomena. One way to describe the irregular nature of the sea surface is the use of wave energy spectrum. Spectral information for wind waves in the Black Sea is extremely limited. Knowledge on spectral characteristics of wind waves would contribute to scientific, engineering and operational coastal and marine activities in the Black Sea. The aim of the present thesis is to investigate characteristics of wind wave spectra for the Eastern Black Sea. This would allow detailed understanding of the nature of the waves occurring in this enclosed basin. Long-term wave measurements obtained by directional buoys deployed offshore at Sinop, Hopa and Gelendzhik were utilized as the three sets of wave data. Records were analyzed to identify them as uni-modal or multi-modal spectra, and occurrences of spectral peaks were computed. Single peaked spectra were studied as belonging to fully arisen or developing sea states. Model parameters of JONSWAP and PM spectra were estimated for the observed spectra by using a least square error method. The records of developing seas were further analyzed to select the ones belonging to stable wind conditions. Fetch dependencies of non-dimensional spectral variables, mean parameters of JONSWAP model spectrum and the envelop of dimensionless spectra were investigated for this data sub-set.

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