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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.
71

Gottfried Winkler ou L'écriture oblique - Lire entre les lignes

Thirion, François 12 December 2011 (has links) (PDF)
Cette thèse propose une recherche en deux temps, tout d'abord la reconstructionde la biographie et bibliographie complète du philosophe et pédagogue allemandGottfried Winkler (1739-1814), notamment par des documents inédits. Père du francmaçon,librettiste de Karl Maria von Weber et citoyen d'honneur de Dresde TheodorHell (1775-1856), son oeuvre n'est aujourd'hui connue que par un ouvrage considérépeut-être à tort comme une simple réédition du théologien réputé Johann Lorenz Mosheim(1693-1755). Cette mécompréhension de son oeuvre littéraire découle d'unetechnique d'écriture particulière que nous avons cherché à décoder.C'est pour cette raison que nous proposons dans un deuxième temps l'élaborationd'une méthodologie d'analyse littéraire fondée sur la théorie de l'" écritureoblique " ainsi que l'a formulée le philosophe Léo Strauss dans son essai La persécutionet l'art d'écrire. Cette méthode nous permet un éclairage différent des textes deGottfried Winkler ainsi qu'une analyse historique et philosophique nouvelle de l'auteur.L'accent de la recherche est donc mis sur une méthode de lecture " post-straussienne", augmentée de concepts anthropologiques, sociologiques et philosophiquesmodernes de l'oeuvre majeure de Winkler pour démontrer qu'il ne s'agit nullementd'un simple éditeur de Mosheim, mais bien d'un penseur représentatif, presque symptomatique,de la réalité d'une génération philosophique discrète, déchirée entre l'espritdes Lumières et la peur de la censure.
72

Investigation of gradient echo MRI for blood vessel imaging and susceptibility-weighted imaging in the human brain

Eissa, Amir 06 1900 (has links)
Despite the vast myriad of applications and the long way it has come, MRI is still a relatively new field of knowledge with much prospect for more advancement and expansion. This work is mainly concerned with two gradient echo imaging methods which are directly or indirectly related to blood vessel imaging as well as iron depiction in the human brain. In each case, new methods are introduced that overcome existing limitations. For blood vessel imaging, 3D Time-of-Flight (TOF) MR angiography (MRA) with its known capability to image arteries as well as veins was implemented at 3.0 T. At this field strength, the significant RF profile variability due to RF inhomogeneity is a liability for circle-of-Willis imaging in the human brain that was overcome by introducing a new means to counter the RF effects through increased slope of the ramped pulse. In addition a new method is introduced for TOF MRA with two-in-one arterial and venous 3D TOF imaging to overcome the significant scan time overhead of a traditional second venous scan and for cutting down RF power utilization. Using this method, total scan time could be reduced by as much as 46% and specific absorption rate (SAR) due to spatial saturation could be reduced by as much as 92%. For iron sensitive imaging, Susceptibility Weighted Imaging (SWI) was developed at 4.7 T. The phase SWI method was used to visualize lesions in Multiple Sclerosis (MS) patients and was experimentally compared to the visibility on standard T2 weighting with results demonstrating visualization of new lesions, with 18% of total lesions exclusively visible on SWI. A new approach to 3D imaging was also introduced to enable accurate oblique SWI scanning while overcoming the current restriction to axial imaging to produce correct phase effects for oblique imaging. New results from oblique phase imaging were presented and the phase measurements from key brain structures were successfully validated against images obtained by the current standard of axial imaging.
73

Variation in resumption requires violable constraints : a case study in Alemannic relativization

Salzmann, Martin January 2009 (has links)
Variation in dative resumption among and within Alemannic varieties of German strongly favors an Evaluator component that makes use of optimality-theoretic evaluation rather than filters as in the Minimalist Program (MP). At the same time, the variation is restricted to realizational requirements. This supports a model of syntax like the Derivations and Evaluations framework (Broekhuis 2008) that combines a restrictive MP-style Generator with an Evaluator that includes ranked violable (interface) constraints.
74

Optimum Linear Transceiver Design for MIMO Systems : An Oblique Projection Framework

Wu, Chun-Hsien 07 May 2007 (has links)
Previous studies have demonstrated that many existing communication systems can be formulated within a unified multirate filterbank transceiver model. A redundant block transmission system implemented via this unified multirate filterbank transceiver model is usually known as a multiple-input-multiple-output (MIMO) system in literature. This dissertation devises an optimum linear block-based precoder and the corresponding equalizer for MIMO systems over perfect reconstruction (PR) channels by exploiting the proposed oblique projection framework. Particularly, two main criteria of interest in a digital communication link with limited transmission power are investigated, namely, average bit error rate (BER) minimization and mutual information rate maximization. The study framework is developed as follows. For a block-based precoder, a received signal model is formulated for the two redundancy schemes, viz., trailing-zeros (TZ) and cyclic-prefix (CP). By exploiting the property of oblique projection, a cascaded equalizer for block transmission systems (i.e., MIMO systems) is proposed and implemented with a scheme, in which the inter-block interference (IBI) is completely eliminated by the oblique projection and followed by a matrix degree of freedom for inter-symbol interference (ISI) equalization. With the available channel state information at the transmitter side, the matrix for ISI equalization of the cascaded equalizer is utilized to design an optimum linear block-based precoder, such that the BER is minimized (or the mutual information rate is maximized), subject to the ISI-free and the transmission power constraints. Accordingly, the cascaded equalizer with the ISI-free constraint yields a cascaded ZF equalizer. Theoretical derivations and simulation results confirm that the proposed framework not only retains identical BER and information rate performances to previous works for cases with sufficient redundancy, but also allows their results to be extended to the cases of insufficient redundancy.
75

Fault and fracture systems related to reactivation of pre-existing structural elements, Devils River Uplift and Maverick Basin, Texas

Smith, Gordon Allen 18 February 2014 (has links)
Pre-existing structural elements can have substantial effects on fracture and fault development in younger strata, especially in areas that undergo significant changes in tectonic setting due to reactivation along older structures. This may affect reservoir permeability, yet remain difficult to detect in subsurface data. The focus of this study centers on two styles of pre-existing structures—Paleozoic thrust belts and Late Triassic rift faults in the Devils River Uplift and Maverick Basin, respectively—which affect the development of faults and fractures in Cretaceous strata. Fault and fracture data were characterized in both the outcrop and within a 3D seismic volume. Furthermore, the role of mechanical stratigraphy on fault and fracture style in both localities was examined. The Pecos River Canyon overlies the Paleozoic Ouachita fold-thrust belt with associated EW and SE-NW trending structures. At the surface, faults are expressed in two predominant orientations (N38E and N70E), which may be predictable angles if the pre-existing structures are reactivated by left lateral oblique slip. Detailed investigation of the fracture development related to these faults was conducted in a dry side canyon along the Pecos River. Mechanical layers were identified and mapped in outcrop to highlight fracture intensity variations between the different layers. The porosity and/or the degree of dolomitization are identified as controls on fracture development, with the lowest strength layer and least fractured being highly dolomitized with the largest porosity of any observed layer in outcrop. Southeast of Lewis Canyon, a 3D seismic of the Maverick Basin reveals linear discontinuities, interpreted as low-offset faults, within the Cretaceous Glen Rose through Austin Chalk that appear similar to those observed in outcrop along the Lower Pecos River. These faults are shown to have an increase in intensity within strata above older Late Triassic-age rift faults. It is proposed that the small faults form during reactivation of the rift faults and exhibit differential degrees of intensity and vertical terminations against six identified mechanical boundaries observed within the 3D seismic volume. / text
76

Multi-Modality Endoscopic Imaging for the Detection of Colorectal Cancer

Wall, Richard Andrew January 2013 (has links)
Optical coherence tomography (OCT) is an imaging method that is considered the optical analog to ultrasound, using the technique of optical interferometry to construct two-dimensional depth-resolved images of tissue microstructure. With a resolution on the order of 10 μm and a penetration depth of 1-2 mm in highly scattering tissue, fiber optics-coupled OCT is an ideal modality for the inspection of the mouse colon with its miniaturization capabilities. In the present study, the complementary modalities laser-induced fluorescence (LIF), which offers information on the biochemical makeup of the tissue, and surface magnifying chromoendoscopy, which offers high contrast surface visualization, are combined with OCT in endoscopic imaging systems for the greater specificity and sensitivity in the differentiation between normal and neoplastic tissue, and for the visualization of biomarkers which are indicative of early events in colorectal carcinogenesis. Oblique incidence reflectometry (OIR) also offers advantages, allowing the calculation of bulk tissue optical properties for use as a diagnostic tool. The study was broken up into three specific sections. First, a dual-modality OCTLIF imaging system was designed, capable of focusing light over 325-1300 nm using a reflective distal optics design. A dual-modality fluorescence-based SMC-OCT system was then designed and constructed, capable of resolving the stained mucosal crypt structure of the in vivo mouse colon. The SMC-OCT instrument's OIR capabilities were then modeled, as a modified version of the probe was used measure tissue scattering and absorption coefficients.
77

Dealing with Cultural Issues in Translating Blog Columns by Jeff Klima

Sundqvist, Sofia January 2011 (has links)
The aim of this essay is to identify and discuss possible solutions to problems regarding the translation of certain cultural references in blog columns by the American author Jeff Klima. More specifically, these cultural references are general cultural aspects, swear words and references to people. General cultural aspects include references to historical events, religious festivities, publications, cultural stereotypes and culturally based idioms. I use Vinay and Darbelnet’s strategies of direct and oblique translation, as well as Nida’s concepts of formal and dynamic equivalence. I also use Newmark’s strategies of semantic versus communicative translation, and Ingo’s adaption strategy. I find that there is no universal solution applicable to all types of culturally related issues in translation, but that every case is unique and requires a unique solution. What can be said, however, is that semantic translations and word-for-word translations are rarely applicable when it comes to cultural issues. True for all issues, however, is that the translator needs to be perfectly clear on what the author is saying and who the receiver, or target reader, is in order to begin to explore which strategy is best to use.
78

Investigation of gradient echo MRI for blood vessel imaging and susceptibility-weighted imaging in the human brain

Eissa, Amir Unknown Date
No description available.
79

Stochastic finite element simulations of real life frontal crashes : With emphasis on chest injury mechanisms in near-side oblique loading conditions

Iraeus, Johan January 2015 (has links)
Introduction. Road traffic injuries are the eighth leading cause of death globally and the leading cause of death among young people aged 15-29. Of individuals killed or injured in road traffic injuries, a large group comprises occupants sustaining a thorax injury in frontal crashes. The elderly are particularly at risk, as they are more fragile. The evaluation of the frontal crash performance of new vehicles is normally based on barrier crash tests. Such tests are only representative of a small portion of real-life crashes, but it is not feasible to test vehicles in all real-life conditions. However, the rapid development of computers opens up possibilities for simulating whole populations of real-life crashes using so-called stochastic simulations. This opportunity leads to the aim of this thesis, which is to develop and validate a simplified, parameterized, stochastic vehicle simulation model for the evaluation of passive restraint systems in real-life frontal crashes with regard to rib fracture injuries. Methods. The work was divided into five phases. In phase one, the geometry and properties of a finite element (FE) generic vehicle buck model were developed based on data from 14 vehicles. In the second phase, a human FE model was validated for oblique frontal crashes. This human FE model was then used to represent the vehicle occupant. In the third phase, vehicle buck boundary conditions were derived based on real-life crash data from the National Automotive Sampling System (NASS) and crash test data from the Insurance Institute for Highway Safety. In phase four, a validation reference was developed by creating risk curves for rib fracture in NASS real-life crashes. Next, these risk curves were compared to the risk of rib fractures computed using the generic vehicle buck model. In the final phase, injury mechanisms in nearside oblique frontal crashes were evaluated. Results. In addition to an averaged geometry, parametric distributions for 27 vehicle and boundary condition parameters were developed as guiding properties for the stochastic model. Particular aspects of the boundary conditions such as pulse shape, pulse angle and pulse severity were analyzed in detail. The human FE model validation showed that the kinematics and rib fracture pattern in frontal oblique crashes were acceptable for this study. The validation of the complete FE generic vehicle buck model showed that the model overestimates the risk of rib fractures. However, if the reported under-prediction of rib fractures (50-70%) in the NASS data is accounted for using statistical simulations, the generic vehicle buck model accurately predicts injury risk for senior (70-year-old) occupants. The chest injury mechanisms in nearside oblique frontal crashes were found to be a combination of (I) belt and airbag loading and (II) the chest impacting the side structure. The debut of the second mechanism was found for pulse angles of about 30 degrees. Conclusion. A parameterized FE generic passenger vehicle buck model has been created and validated on a population of real life crashes in terms of rib fracture risk. With the current validation status, this model provides the possibility of developing and evaluating new passive safety systems for fragile senior occupants. Further, an injury mechanism responsible for the increased number of outboard rib fractures seen in small overlap and near-side oblique frontal impacts has been proposed and analyzed. / Vinnova Project: Real Life Safety Innovations
80

Įstrižojo astigmatizmo kompiuterinis modeliavimas sferiniuose ir asferiniuose lęšiuose / The computer modeling of oblique astigmatism in spherical and aspherical lenses

Andrulaitytė, Giedrė 16 July 2014 (has links)
Bakalauro darbą „Įstrižojo astigmatizmo kompiuterinis modeliavimas sferiniuose ir asferiniuose lęšiuose“ sudaro įvadas, 5 dėstymo skyriai, išvados ir priedai. Darbe pateikiami 50 paveikslai ir 2 lentelės, cituojami 16 literatūros šaltinių. Darbo apimtis 66 lapai. Darbe apibendrinta literatūra apie lęšių aberacijas, jų įtaką regėjimo kokybei, bei minimalizavimą asferiniais lęšiais. Taip pat pateikiami matematiniai sferinių ir asferinių lęšių modeliai, bei įstrižojo astigmatizmo analizė šiuose lęšiuose. Įvade iškeliami darbo tikslai ir uždaviniai. Pirmajame skyriuje pateikta teorinė medžiaga apie lęšių aberacijas, antrajame – apie sferinius ir asferinius lęšius. Išanalizuoti galimi asferinių lęšių paviršiai ir jų pranašumas prieš sferinius paviršius. Trečiajame skyriuje pateikiamas matematinis spindulių eigos modelis sferiniame paviršiuje. Ketvirtajame – matematinis spindulių eigos modelis asferiniame paviršiuje. Penktajame skyriuje lyginami kompiuterinių modelių pagalba gauti įstrižojo astigmatizmo apibūdinti rezultatai, tangentinėmis paklaidomis. / The bachelor’s thesis „The computer modeling of oblique astigmatism in spherical and aspherical lenses” consists of introduction, 5 chapters, conclusions and attachments. The thesis introduces 50 figures, 2 tables and refers to 16 literary sources. The volume of the work is 66 pages. The work summarizes the literature which describes the lens aberrations, its influence to quality of vision and reduction by using aspheric lenses. There is also included mathematical models of spherical and aspheric lenses, and analysis of oblique astigmatism in them. The introduction sets the aims and the goals of the study. The first chapter contains theoretic material about lens aberrations, the second – about spherical and aspheric lenses, the analysis about available surfaces of aspheric lenses and advantages of them. The third chapter contains mathematical model of light rays pathway in spherical lenses. The fourth chapter contains mathematical model of light rays pathway in aspheric lenses. The fifth chapter contains comparison of oblique astigmatism described as tangential errors in those two models.

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