88 resultados para attic


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Latin and English on opposite pages.

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A fundamental study of the fluid dynamics inside an attic shaped triangular enclosure with cold upper walls and adiabatic horizontal bottom wall is reported in this study. The transient behaviour of the attic fluid which is relevant to our daily life is examined based on a scaling analysis. The transient phenomenon begins with the instantaneous cooling and the cooling with linear decreases of temperature up to some specific time (ramp time) and then maintain constant of the upper sloped walls. It is shown that both inclined walls develop a thermal boundary layer whose thicknesses increase towards steady-state or quasi-steady values. A proper identification of the timescales, the velocity and the thickness relevant to the flow that develops inside the cavity makes it possible to predict theoretically the basic flow features that will survive once the thermal flow in the enclosure reaches a steady state. A time scale for the cooling-down of the whole cavity together with the heat transfer scales through the inclined walls has also been obtained through scaling analysis. All scales are verified by the numerical simulations.

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The heat transfer through the attics of buildings under realistic thermal forcing has been considered in this study. A periodic temperature boundary condition is applied on the sloping walls of the attic to show the basic flow features in the attic space over diurnal cycles. The numerical results reveal that, during the daytime heating stage, the flow in the attic space is stratified; whereas at the night-time cooling stage, the flow becomes unstable. A symmetrical solution is seen for relatively low Rayleigh numbers. However, as the Ra gradually increases, a transition occurs at a critical value of Ra. Above this critical value, an asymmetrical solution exhibiting a pitchfork bifurcation arises at the night-time. It is also found that the calculated heat transfer rate at the night-time cooling stage is much higher than that during the daytime heating stage.

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Unsteady natural convection inside a triangular cavity subject to a non-instantaneous heating on the inclined walls in the form of an imposed temperature which increases linearly up to a prescribed steady value over a prescribed time is reported. The development of the flow from start-up to a steady-state has been described based on scaling analyses and direct numerical simulations. The ramp temperature has been chosen in such a way that the boundary layer is reached a quasi-steady mode before the growth of the temperature is completed. In this mode the thermal boundary layer at first grows in thickness, then contracts with increasing time. However, if the imposed wall temperature growth period is sufficiently short, the boundary layer develops differently. It is seen that the shape of many houses are isosceles triangular cross-section. The heat transfer process through the roof of the attic-shaped space should be well understood. Because, in the building energy, one of the most important objectives for design and construction of houses is to provide thermal comfort for occupants. Moreover, in the present energy-conscious society it is also a requirement for houses to be energy efficient, i.e. the energy consumption for heating or air-conditioning houses must be minimized.

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The effects of periodic thermal forcing on the flow field and heat transfer through an attic space are examined numerically in this paper. We consider the case with a fixed aspect ratio of 0.5 and a fixed Grashof number of 1.33×106. The numerical results reveal that, during the daytime, the flow is stratified; whereas at the night-time, the flow becomes unstable. A number of regular plumes and vortices are observed in the contours of isotherms and stream functions respectively. Moreover, the flow appears to be symmetric during the daytime, and becomes asymmetric at the night-time. It is also found that the flow is weaker during the daytime than that at the night-time in the present case, and the calculated heat transfer rate at the night-time is approximately three times greater than the heat transfer rate during the daytime.

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To reduce the natural convection heat loss from enclosures many researchers used convection suppression devices in the past. In this study a single baffle is used under the top tip to investigate numerically the natural convection heat loss in an attic shaped enclosure which is a cost effective approach. The case considered here is one inclined wall of the enclosure is uniformly heated while the other inclined wall is uniformly cooled with adiabatic bottom wall. The finite volume method has been used to discretize the governing equations, with the QUICK scheme approximating the advection term. The diffusion terms are discretized using central-differencing with second order accuracy. A wide range of governing parameters are studied (Rayleigh number, aspect ratio, baffle length etc.). It is observed that the heat transfer due to natural convection in the enclosure reduces when the baffle length is increased. Effects of other parameters on heat transfer and flow field are described in this study.

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The memoirs were written in New York in 1999. Description of the childhood of Rosemarie Schink, the author's mother, in the rural area of Meuszelwitz, Thuringia, where her grandfather, Franz Harnish, was the station manager. Rosemarie Schink eloped to Amsterdam with the Dutch Jew Judah Easel in 1931. The marriage fall apart soon thereafter, and Rosemarie was taken under the wings of her father-in-law Joseph Easel. The couple stayed officially married until their divorce in 1940, and Rosemarie worked in the pension of her in-laws. She had a long affair with the German Jew Guy Weinberg from Hamburg, a married man who was living in Amsterdam and became the father of her daughter Julia. Description of the Weinberg family history. In 1941 Rosemarie Schink married the Austrian Jewish lawyer Herbert Mauthner, the eldest of three sons of Robert Mauthner, director of the Bodenbacher-Dux Railroad and Melanie Leitner, daughter of a wealthy family from Veszprem, Hungary. Mauthner family history and nobility of the Leitner family, who were admitted to the court of the Austrian Kaiser Franz Joseph.

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383 p. ; P.315-383: "Erauso Kateriñe" antzezlanaren edizioa dago.

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[ES] En este trabajo se estudia gár como marcador del discurso en un corpus del griego ático, el discurso Pro corona de Demóstenes. Gár introduce secciones informativas tanto en el nivel local como en el global. En el primero añade información complementaria, mientras que en el segundo indica la introducción de un nuevo tema como desarrollo de una información preliminar. La función común de gár en los dos casos es marcar la información que introduce como suplementaria.

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Presentado en la Jornada de Teatro Griego "Teatro, poesía y pensamiento en la Atenas del siglo V a. C.", Valencia, 19-20 de noviembre de 2007.

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[ES] El objetivo que se propone el presente trabajo es poner de manifiesto la influencia de la Comedia Atica en la Declamación XXVI de Libanio, una de las llamadas "declamaciones etopoéticas", que se centran en la descripción de caracteres. Estos se construyen a partir de los tipos fijados por la comedia, en el caso de la obra estudiada un δύσκολος y una mujer charlatana, personajes con una amplia tradición detrás de ellos. Por otra parte, se aborda desde un punto de vista "cómico" el tema del matrimonio, sobre el que tratan también, en un sentido muy diferente, los moralistas y los autores de epitalamios. Aflora además la influencia de la comedia ática en el uso de diversos elementos para la caracterización de los personajes (hipérboles, riqueza en imágenes y comparaciones), así como de ciertos recursos propios del género, principalmente el πνῖγος.

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Presentado en el Simposio "La imagen del sexo en la antigüedad: ciclos de renovación de la vida", organizado por el Instituto de Historia del CSIC y celebrado en Barcelona del 21 al 23 de marzo de 2002.

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[EN] This paper examines how the female characters in Greek novels have recourse to false speech. Based on an analysis of female speech in Attic tragedy, which was one of the literary genres that exerted the greatest influence on speech parts of the novels, a study is conducted to find out which characters in the novel employ false speech and their purpose in doing so. Two types of false speech were identified: the defensive one, used by the female protagonists or by secondary characters of similar social and ideological status, and the offensive one, used by characters of lower rank, and blameworthy morality within the ideological love's frameword publicized through the novel.