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iv Performance prediction of HAWTs is important because it gives an idea about the power production of a HAWT in out of design conditions without making any experiments. Since the experiments of fluid mechanics are difficult to afford, developing some models is very beneficial. There are some models developed about this subject using miscellaneous methods. In this study, one can find &ldquo / Vortex Theory&rdquo / among one of these theories. Some basic 3D aerodynamics was discussed in order to make the reader to understand the main subject of this study. Just after that, performance prediction of constant speed, stall controlled HAWTs was discussed. In order to understand the closeness of this theory to experiments, as a sample, NREL &ldquo / Combined Experiment Rotor&rdquo / was considered. Performances obtained by AEROPOWER, written in Visual Basic 6.0 and Excel combination, and experimental results were compared for different wind velocities. Acceptable results were obtained for wind speeds not much different than the design wind speed. For relatively lower wind speeds, due to &ldquo / turbulence&rdquo / , and for relatively higher wind speeds, due to &ldquo / stall&rdquo / , the program did not give good results. In the first case it has not given any numerical result. Power curves were obtained by only changing the settling angle, and only changing the rotor angular speed using AEROPOWER. It was seen that, both settling angle and rotor rpm values influence the turbine power output significantly.

In recent years, especially in the crowded city-centers where land prizes have become extremely high, tall buildings with more than 30 floors have started to be designed and constructed in Turkey. On the other hand, the technical improvements have provided the opportunity of design and construction of more slender structures which are influenced by the wind actions more. If the building is flexible, wind can interact with it so the wind induced oscillations can be significantly magnified. In order to analyze the response of such buildings under wind effects, wind tunnel tests are accepted to be the most powerful tool all over the world. In this study, a series of tests were performed in Ankara Wind Tunnel on a model building in the shape of a rectangular prism. For the similitude of flow conditions, passive devices were designed. The response of the model building was measured through a high frequency base balance which was designed specifically for this case study. Through the tests, the effects of turbulence intensity, vortex shedding and wind angle of attack on the response of the building were questioned. Finally, the results were compared with the results of various technical specifications about wind.

Une monographie sur la ville antique de Sura s’imposait pour mettre l’accent sur un site-clef, peu étudié, parmi les villes fortifiées du Moyen-Euphrate. L’objectif de ce travail est d’en offrir une description et une analyse poussées et d’élargir le champ des recherches à l’ensemble de la région. À 22 km à l’ouest de Raqqa et à 29 km au nord de Resafa, à l’emplacement du village moderne d’«el-Hammam», Sura (autrefois «Souriya») domine la rive droite de l’Euphrate. Le site est une agglomération fortifiée de forme rectangulaire (76,5 ha) divisée en deux parties, enceinte nord-est et enceinte sud-ouest. Nous présentons Sura de l’époque romaine jusqu’au début de l’époque omeyyade (Ier-VIIIe s.), d’après les résultats de nos recherches qui, entre 2003 et 2011, se sont concentrées sur trois pôles : fortifications, structures domestiques et édifices civils (fouilles intra-muros), nécropole(fouilles extra-muros). Nous étudions ensuite sa culture matérielle à travers le mobilier archéologique et les éléments architecturaux issus des fouilles. Les résultats de ces recherches doivent enrichir le dossier des sites de référence de l’Antiquité tardive pour la région de l’Euphrate et de la Syrie du Nord, en offrant une base de comparaison de premier ordre pour l’architecture civile et funéraire et, surtout, pour le matériel céramique, le verre, les inscriptions. Occupant une position géographique stratégique, Sura fut florissante pendant l’époque romaine et byzantine, jusqu’à la conquête arabe de la région en 639-640, qui scella son déclin – contrairement aux autres villes de l’Euphrate –, puis elle ne fut plus occupée que par des chrétiens locaux, dans des habitats modestes. / A monograph about the ancient city of Sura was necessary in order to bring to light a site little studied so far, in spite of its key importance among the Middle Euphrates fortified towns. The present work aims at offering a thorough description and analysis of it, while broadening the scope of comparison to its larger region. Sura(previously “Suriya”) is situated 22 km west of Raqqa and 29 km north of Resafa, on the location where nowadays stands the village of “el-Hammam”, overlooking the right bank of the river Euphrates. The site, a fortified agglomeration of rectangular shape (76,5 ha), is divided into two parts, the northeast and the southwest enclosures. We present Sura from Roman times until the beginning of the Umayyad period (1st-8th cent.), through the results of our researches, which, from 2003 to 2011, have been focusing, intra-muros, on its fortifications, on its domestic and public structures, and, extra-muros, on its necropolis, then through its material culture, that is, thesmall finds and architectural elements. Such a research should contribute to enhancing the extant knowledge about Late Antiquity in the Euphrates region and North Syria, by bringing forth an additional reference site, especially for civil and funerary architecture and, above all, pottery, glass, and inscriptions. The floruit of Sura, set in a strategic location, lasted from the Roman through Byzantine times, until the Arab conquest of the region, in 639-640, threw it into oblivion – a fate not shared by other cities on the Euphrates. Afterwards, only local Christians maintained some modest settlement there.