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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.
11

Besetzung und Behandlung der Bläser im Orchester Mozarts am Beispiel der Opern /

Grundner, Bernhard, January 1998 (has links)
Diss.--München--Univ., 1998. / Bibliogr. p. 288-307.
12

Studies of microbial methane oxidation in deep-sea hydrothermal vent environments /

De Angelis, Marie Agatha. January 1989 (has links)
Thesis (Ph. D.)--University of Washington, 1989. / Vita. Includes bibliographical references (leaves [145]-152).
13

Charges de vent sur les conducteurs électriques : étude comparative des principales normes

Lafrenière, Martin. January 2002 (has links)
Thèses (M.Sc.A.)--Université de Sherbrooke (Canada), 2002. / Titre de l'écran-titre (visionné le 20 juin 2006). Publié aussi en version papier.
14

Étude expérimentale de l'effet de la turbulence de grande échelle sur les vibrations éoliennes d'un long cylindre flexible

Laguë, Frédéric. January 2002 (has links)
Thèses (M.Sc.A.)--Université de Sherbrooke (Canada), 2002. / Titre de l'écran-titre (visionné le 30 août 2006). Publié aussi en version papier.
15

Exploring the diversity and physiological significance of attached microorganisms in rock-hosted deep-sea hydrothermal environments /

Schrenk, Matthew Owen. January 2005 (has links)
Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (leaves 159-190).
16

Morphogenèse des moulins à vent d’Iran, techniques de gestion du vent de manière architectonique / Morphogenesis of windmills of Iran, architectural techniaue of wind management

Moshtaghe Gohari, Kambiz 12 January 2018 (has links)
« Le passé est un pays étranger : ils font les choses différemment là-bas » L.P. Hartly Nous avons souhaité nous pencher sur l’histoire des premiers moulins à vent. Plusieurs raisons à cela : une grande partie de l’histoire du moulin à vent demeure obscure et entre autres ; deux choses sont mal connues : la première concerne la date où le moulin à vent à axe vertical apparu pour la première fois en Iran (Perse antique), et la deuxième son évolution, les différents types de cette invention. Dernière raison justifiant la nécessité de notre recherche : il n’y a pas encore d’hypothèse claire permettant d’établir un lien entre les différents types des moulins a vent a axe vertical et présentant une chronologie datée et documentée de l’évolution des types différents, en particulier le moulin à vent à axe vertical iranien. Les sources d’énergie comme le vent – et le moulin à vent sont considérées comme une technologie médiatrice entre le vent et la société humaine. R. J. Forbes , l’historien de la technologie allemand, défendait l’idée que les « moteurs primaires » étaient la « clé de voûte de la technologie ». En utilisant comme critère ces « moteurs primaires », il distingue cinq périodes dans l’histoire de la technologie de l’humanité : l’ère de l’utilisation du muscle d’humain, l’ère de l’utilisation du muscle animal, l’ère de l’énergie fournie par l’eau, l’ère de l’énergie créée par la vapeur et l’ère de l’énergie atomique. Dans sa classification, Forbes n’a pas inclus l’ère de l’énergie du vent ; nous verrons que cette ère est le chaînon manquant entre l’ère de l’énergie hydraulique et l’ère de l’énergie fournie par la vapeur. Avec l’utilisation de l’énergie éolienne, cette ère devient par ailleurs la plus longue de l’histoire de l’utilisation des énergies. Parmi les technologies connues en matière de production d’énergie dans l’Antiquité figure la technologie du moulin à vent, qui a des liens directs avec les deux ères longues et importantes en matière d’utilisation de l’énergie : l’ère de l’énergie hydraulique et l’ère de l’énergie fournie par la vapeur. Malgré tout ce que l’on sait sur l’histoire du moulin à vent européen, l’origine et la diffusion de cette invention technique ne sont pas claires. Maurice Daumas écrit que : « L’origine et la diffusion du moulin à vent posent encore aux historiens de nombreux problèmes et de non moins nombreuses énigmes ». Il manque une chronologie des divers types de moulins à vent dans les diverses civilisations ; par conséquent, une théorie présentant cette diversité architecturale et technique dans le plateau d’Iran fait défaut encore aujourd’hui. La diffusion du moulin à vent dans le monde antique, y a compris l’Iran, pose également question. Une partie importante de cette thèse sera donc consacrée à répondre à ces questions, particulièrement en Iran, dans le but d’éclaircir autant que possible l’origine et la diffusion de cette invention architecturale et technique / "The past is a foreign country: they do things differently over there"L.P. Hartly We wanted to look at the history of the first windmills. There are several reasons for this: much of the history of the windmill remains obscure and among others; two things are poorly known: the first relates to the date when the vertical axis windmill appeared for the first time in Iran (ancient Persia), and the second its evolution, the different types of this invention. The last reason for the need for our research is that there is as yet no clear hypothesis for linking the different types of vertical wind mills with a dated and documented chronology of the evolution of types in particular the Iranian vertical axis windmill. Energy sources like the wind - and the windmill are seen as a mediating technology between wind and human society. R. J. Forbes, the German historian of technology, argued that "primary engines" were the "keystone of technology". Using as a criterion these "primary engines," he distinguishes five periods in the history of human technology: the age of human muscle utilization, the era of animal muscle utilization, the era of energy provided by water, the era of energy created by the vapor and the era of atomic energy. In his classification, Forbes did not include the era of wind energy; we shall see that this era is the missing link between the era of hydraulic energy and the era of energy supplied by steam. With the use of wind energy, this era is also the longest in the history of energy use
17

The Effect of Sprinkler Sprays on Fire Induced Mass Flow Rates

Crocker, Jeremiah 30 May 2008 (has links)
"Performance based methodologies are becoming increasingly common in fire safety due to the inability of prescriptive codes to account for every architectural feature. Fire Sprinkler suppression systems have long been used to provide property protection and enhance life safety. However, very few methodologies exist to account for the impact of sprinkler sprays on fire scenarios. Current methods are extremely complicated and difficult to use as an engineering tool for performance based design. Twenty four full scale fire tests were conducted at Tyco Fire Suppression & Building Products Global Technology Center to determine a simple method for accounting for the impact of a single residential sprinkler on fire induced doorway flows. It was found that a spraying sprinkler reduced the mass flows at the doorway while maintaining two stratified layers away from the sprinkler spray. The mass flow reduction was consistent and could be predicted through the use of a simple buoyancy based equation. The current study suggests that the buoyancy equation can be altered through the use of a constant cooling coefficient (equal to 0.84 for a Tyco LFII (TY2234) sprinkler) based on the test results reported in this paper. This study is a proof of concept and the results suggest the methodology can be applicable to similar situations."
18

Hydrology and thermomechanics of liquid-dominated hydrothermal systems in Iceland

Axelsson, Gudni 06 June 1985 (has links)
Low-temperature hydrothermal activity in Iceland is apparently mostly controlled by dikes and fractures. Conventional methods of production data analysis are not readily applicable in cases of heterogeneous/anisotropic fracture dominated hydrothermal systems. Moreover, the dikes and fractures may control the heat uptake mechanism of low-temperature activity. The free-surface response functions of analytical reservoir models are presented and methods for analyzing production data on the basis of such models are developed. Based on a homogeneous and isotropic half-space model apparent permeability estimates of 0.7 millidarcy are obtained for two low-temperature systems in Tertiary strata in N-Iceland whereas estimates of 5-20 millidarcy are obtained for two systems in Quaternary strata in SW-Iceland. A vertical two-dimensional flow model is, however, more consistent with the apparent linear dike/fracture control of many hydrothermal systems and results in higher permeability estimates. Methods of simulating long term production data by simple lumped capacitor/conductor ladders based on only production/drawdown data are developed and the responses of analytical as well as real systems are shown to be easily simulated by such simple systems. The parameters of simulation ladders also provide information on global hydrological characteristics of hydrothermal systems. A possible dike/fault controlled source mechanism of low-temperature activity in Iceland is considered. This process involves the downward migration of open sections of unwelded quasi-vertical fractures resulting from cooling and contraction of the adjacent rock, in conjunction with vertical heat transfer in the fracture. The rate of downward migration is estimated and found to depend very strongly on the magnitude of the horizontal regional stress. Stress conditions may therefore determine whether a low-temperature system can evolve at a given location as well as determine the intensity of hydrothermal activity. / Graduation date: 1986
19

Characteristic morphology, backscatter, and sub-seafloor structures of cold-vents on the Northern Cascadia Margin from high-resolution autonomous underwater vehicle data

Furlong, Jonathan 11 June 2013 (has links)
In this thesis seafloor cold vents are examined using autonomous underwater vehicle (AUV) and remotely operated vehicle (ROV) data on the Northern Cascadia margin. These data were collected in a 2009 joint cruise between the Monterey Bay Aquarium Research Institute (MBARI) and Natural Resources Canada (NRCan). High- resolution bathymetry data, acoustic reflectivity (backscatter) data, and 3.5 kHz sub bottom profiler data were examined for cold-vent-related features that include pockmarks, chemosynthetic biological communities (CBC), and authigenic carbonate. Additionally subsequent ROV observations, sediments from push cores and seafloor video/photos were used to ground truth AUV data. Numerous prolific venting sites were examined in detail and a model for the evolution of venting was generated. Vents are categorized as juvenile, intermediate, or mature depending on the presence and or absence of cold-vent-features. High near-surface reflection amplitudes are coincident with an anomalous area of seafloor backscatter. In June of 2012, NEPTUNE (North East Pacific Time-series Underwater Networked Experiment) collected a near-surface push core with their ROV ROPOS (Remotely Operated Platform for Ocean Sciences) in the high reflective area. The retrieved core showed stacked turbidites in the top 0.5 meters of the sediment column. Closely spaced high-velocity turbidite sands are highly reflective and inhibit acoustic penetration to depth. The presence of high-density, high-velocity sands in the near surface is linked to steady ocean bottom currents. These bottom currents progress northeast to southwest over the study area and differentially erode the surface sediments by removing muds and leaving heavy sands over the exposed area. / Graduate / 0373 / 0374 / jonfurlong@hotmail.com
20

A fanfare for the makers, for wind ensemble : score and analysis

Ada, Stephen L. January 1997 (has links) (PDF)
No description available.

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