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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.
221

Analyse der neuen LTH-Methode zur Massenschätzung von Flugzeugbaugruppen

Pape, Arlind January 2018 (has links) (PDF)
In dieser Projektarbeit geht es um die Abschätzung von Massen der Hauptbaugruppen großer ziviler Verkehrsflugzeuge (MTOM > 40 t), sowie um die Abschätzung der Betriebsleermasse. Die Projektarbeit analysiert die 2013 im Luftfahrttechnischen Handbuch (LTH) erschienene Massenschätzmethode MA 401 12-01 B von F. Dorbarth und vergleicht diese Methode mit anderen früher veröffentlichten Methoden, die von Fernandes da Moura bereits 2001 analysiert wurden. Für die Analyse werden ausgewählte Flugzeugmuster (A320-200, A330-200, A340-300 und B737-200) und deren tatsächliche Massen der Hauptbaugruppen sowie Betriebsleermassen genutzt. Die Abweichungen zwischen den berechneten und den tatsächlichen Massen werden für jede Methode in Diagrammen veranschaulicht. Es zeigt sich dabei, dass die Massenschätzmethode aus dem Luftfahrttechnischen Handbuch nur geringe Abweichungen im Vergleich zu den tatsächlichen Massen aufweist. Damit werden die eigenen Angaben zur Genauigkeit der LTH-Methode bestätigt. Die Abweichungen sind geringer als bei älteren und generelleren Methoden wie sie von Fernandes da Moura untersucht wurden. Dies entspricht der Erwartung, dass eine neuere Methode, die auf Flugzeuge einer bestimmten Art beschränkt ist, auch genauere Ergebnisse liefert. Insgesamt hat sich die LTH-Methode als übersichtliche und hinreichend genaue Methode zur Massenabschätzung im frühen Flugzeugentwurf erwiesen. Die Abweichungen lagen in der Regel unter 5 % und nur in Ausnahmefällen wurde eine Abweichung von 10 % überschritten.
222

Diverzita pářícího chování švábů (Blattodea: Blaberidae) / Diversity of cockroach mating behaviour (Blattodea: Blaberidae)

Dvořák, Tomáš January 2017 (has links)
Mating behaviour of cockroaches is spectacular phenomenon with three different mating patterns traditionally distinguished. The most common and probably ancestral is type A - female climbing. Then it is type B - male climbing and type C - no climbing. Mating type was described in around 30 Blaberidae species. As it is the only cockroach family where all three types are present, it is an interesting model group for studying evolutionary questions. The main goal of the thesis was detail exploration and description of mating sequences in 21 Blaberidae species, 17 of which haven't been examined in this aspect before. An intrageneric diversity in mating patterns (genus Pycnoscelus) was described for the first time. Moreover, in case of P. tenebrigera, it was not possible to assign its mating pattern to any of the three traditional types. Multidimensional statistical analysis and biological interpretation of qualitative behavioural elements revealed two well separated clusters of mating sequensces. Consequently, we propose to distinguish only two types of mating pattern - ancestral type (identical with type A) and derived type. We also discussed the relationship between wing reduction and occurence of derived mating types. Evaluation of quantitative behavioural elements revealed positive correlation between...
223

Performing Protest in Cross-Cultural Spaces: Paul Robeson and Othello

Sawyer, Robert 01 September 2017 (has links)
When the famous African-American actor and singer Paul Robeson played the lead in Shakespeare's Othello in London in 1930, tickets were in high demand during the production's first week. The critical response, however, was less positive, although the reviews unanimously praised his bass-baritone delivery. When Robeson again played Othello on Broadway thirteen years later, critics praised not only his voice but also his acting, the drama running for 296 performances. My argument concerning Robeson uses elements first noted by Henri Lefebvre in his seminal work, The Production of Space, while I also draw on Paul Connerton's work on commemorative practices. Using spatial and memorial theories as a backdrop for examining his two portrayals, I suggest that Robeson's nascent geopolitical awareness following the 1930 production, combined with his already celebrated musical voice, allowed him to perform the role more dramatically in 1943.
224

The Structural Suitability of Tensegrity Aircraft Wings

Mills, Austin Shelley 22 June 2020 (has links)
No description available.
225

Arabidopsis Cohesin proteins: WAPL, CTF7 and PHD finger proteins: MMDL1, MMDL2 are essential for proper meiosis, gamete development and plant growth

Mitra, Sayantan January 2017 (has links)
No description available.
226

The Black O'Neill: African American Portraiture in Thirst, The Dreamy Kid, Moon of the Caribbees, The Emperor Jones, The Hairy Ape, All God's Chillun Got Wings, and The Iceman Cometh

McKnight, Harry W., Jr. 10 December 2012 (has links)
No description available.
227

Paranormální romance: pokus o vymezení subžánru v kontextu young adult literature / Paranormal romance: an attempt to define the subgenre in the context of young adult literature

Ditrychová, Martina January 2016 (has links)
This diploma thesis thematically follows up one of subgenres of young adult popular literature - paranormal romance. Its main aim is to create a comprehensive definition of this subgenre on the basis of interpretation of representative sagas - Twilight by Stephenie Meyer (Twilight, New Moon, Eclipse, Breaking Dawn), Hush, Hush by Becca Fitzpatrick (Hush, Hush, Crescendo, Silence, Finale), Nightshade by Andrea R. Cremer (Nightshade, Wolfsbane, Bloodrose, Snakeroot), Wings by Aprilynne Pike (Wings, Spells, Illusions, Destined) and Anna Dressed in Blood by Kendare Blake (Anna Dressed in Blood, Girl of Nightmares). The thesis was divided into eight chapters. In the first chapter we have outlined the historical development of paranormal romance, in the second part we focused on its genre characteristic. In the third and fourth chapters we tried to create a prototype of heroine and hero of this subgenre. The fifth part is about the steady plot schemes in paranormal romances. In the sixth chapter we have tried to determine a model form of relationship main pair of lovers in the analyzed subgenre. In the seventh part we discussed conflict between everyday reality and the supernatural and the social hierarchy in the fiction world of paranormal romances and we introduced supernatural species and races that...
228

Wing in Ground Effect

Mondal, Partha January 2013 (has links) (PDF)
The thesis presents a two pronged approach for predicting aerodynamics of air- foils/wings in the vicinity of the ground. The first approach is effectively a model for ground effect studies, employing an inexpensive Discrete Vortex Method for the 2D pre- dictions and the well known Numerical lifting line theory for the 3D predictions. The second one pertains to the dynamic ground effect analysis which employs the state of the art moving mesh methodology based time accurate CFD. In that sense, the thesis deals with two ends of spectrum in the ground effect analysis; one, a model to be used in the concept design phase and the other an advanced CFD tool for analysis. The proposed model for ground effect studies is based on the well known Discrete Vortex Method (DVM). An important aspect of this method is that it employs what is referred to as the Generalized Kutta Joukowski Theorem (GKJ), meant for interaction problems with multiple vortices, for predicting the lift (and drag) within a potential flow framework. After ascertaining the correctness of using the GKJ theorem for lift prediction for airfoils in ground effect, a modified DVM is presented as a model for ground effect predictions. As per this model, knowing the free stream lift and drag (either from an ex- periment or from a RANS computation) the aerodynamics of the section in ground effect can be predicted. The model is effectively built by constraining the DVM to produce the reference lift/drag in the free stream. The accuracy of the model, particularly for the more relevant high lift sections used during take-off and landing, is systematically estab- lished for a number of test cases. Knowing the sectional ground effect, the extension to 3D analysis is very simple and this is achieved through the well known Numerical Lifting Line theory. The efficacy of the proposed method for the 3D applications is demonstrated using a high lift wing in ground effect. It is worth noting that the proposed model predicts the lift and drag very accurately, practically at no computational cost as compared to modern RANS based CFD tools requiring over 40 or 50 million volumes at a high computational cost and intense human intervention for generating the grids for every ground clearance. The other aspect of the thesis pertains to what is referred to as the Dynamic Ground Effect. Normally the CFD computations mimic the ground effect experiments in simulat- ing the ground effect. These simulations do not maintain geometric similarity with the actual landing or take-off sequence of the aircrafts and this can only be achieved when the simulations are dynamic. Dynamics is also important in case of combat aircrafts (particularly their naval versions) with an aggressive landing and take-off. The dynamic ground effect simulations also provides a framework for simulating varied gust conditions. This dynamic simulation of the ground effect is accomplished using a novel sinking grid methodology, which allows the grids to sink in the ground as the aircraft approaches the ground along the glide path. These simulations make use of the state of the art, time accurate moving grid methods and therefore can be computationally expensive. Never- theless, the utility of such computations in terms of their ability to produce continuous data has been highlighted in the thesis. In that sense, these dynamic computations will be cheaper as compared to the static simulations to produce data at the same level of resolution.

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