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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.
31

Influence des facteurs non syntaxiques sur l'accord en nombre : approche développementale / Influence of non syntactic factors in number agreement : developmental approach

Lusson, Charlotte 14 October 2013 (has links)
Cette thèse examine l'influence qu'exercent certaines caractéristiques de l'élément à accorder sur les performances de rédacteurs francophones, novices et experts, dans différentes tâches de traitement de l'accord en nombre. Une première série d'expériences teste l'impact de la présence d'informations morpho-phonologiques et conceptuelles portées par le verbe. Les résultats montrent qu'à partir du CM2, une terminaison verbale phonologiquement distincte entre le singulier et le pluriel améliore le traitement de l'accord La présence d'une information conceptuelle au niveau du verbe conduit en revanche les participants, dès le CMl, à commettre davantage d'erreurs d'accord. Le traitement d'un verbe dont l'action est nécessairement accomplie par plusieurs agents semble engendrer des perturbations au moment de l'accord. Les informations morpho-phonologiques et conceptuelles influencent également les durées de la production de phrases dictées et le nombre d'erreurs d'accord correctement détectées dans une tâche de révision. Une seconde série d'expériences analyse I'impact du coût attentionnel engendré par la complexité de la gestion de l'orthographe lexicale sur le traitement de l'accord, en manipulant la fréquence lexicale et la consistance orthographique. L'effet de ces variables sur les eneurs commises par les enfants suggère que la probabilité d'accorder en nombre varie en fonction de la fréquence (facteur lexical) et de la consistance (facteur ous-lexical) des mots et ce, du CEI au CM2. Dans l'ensemble, les résultats de cette thèse suggèrent que I'accord n'est pas traité indépendamment de certaines caractéristiques propres à l'élément à accorder. / This thesis examines the influence of some characteristics of the agreement target on the performances of novice and expert writers in number agreement via different tasks. A first series of experiments studies the impact of the presence of morpho-phonological and conceptual information carried by the verb. Results show that from the 5th grade, aphonologically distinct verbal ending between singular and plural improves agreement processing. The presence of a conceptual information on the verb leads however participants from the 4th grade to commit more agreement errors. The processing of a verb whose action is necessarily accomplished by several agents seems to create disturbances during theagreement. Morpho- phonological and conceptual information also influence the duration of production of dictated sentences and the number of agreement errors correctly detected in revision tasks. A second series of experiments analyzes the impact of cognitive cost incurred by the complexity of the management of lexical spelling on the treatment of agreement, by manipulating lexical frequency and orthographic consistency. The effect of these variables on the errors committed by children suggests that the probability of agreement in number varies with frequency (lexical factor) and consistency (sub- lexical factor) and this, from 2nd to 5th grade. Overall, the results of this thesis suggest that agreement is not processed independently from some specific characteristics of the agreement's target
32

Etude de la compaction dynamique de mousses polymères : Expériences et modélisation / Investigation of the Dynamic Compaction of Polymeric Foams : Experiments and Modeling

Pradel, Pierre 13 December 2017 (has links)
Les mousses polymères trouvent de nombreuses applications industrielles en tant qu’isolants thermiques, matériaux de structuration ou atténuateurs de choc. En effet, il s’agit de matériaux légers, possédant un excellent rapport masse / rigidité, et demandant de faibles coûts de production.Une des applications envisagées par le CEA est la protection de structures face à des chargements mécaniques générés lors d’irradiations laser ou lors d’impacts de débris micrométriques.L’objectif principal de cette thèse est d’évaluer la capacité d’atténuation d’une mousse expansée en polyuréthane rigide et d’une mousse syntactique à matrice époxy face à des sollicitations dynamiques extrêmement rapides (> 106 s−1) et intenses (> 10 GPa). Des essais quasi-statiques de compression / décompression et des expériences dynamiques ont ont été réalisés pour analyser le comportement de ces deux mousses pour des vitesses de déformation allant de 10−3 à 106 s−1. L’analyse des résultats expérimentaux montre que ces mousses polymères ont une phase de comportement élastique suivie d’une phase de compaction conduisant à des déformations irréversibles importantes. Les seuils de compaction sont estimés à 9 MPa pour la mousse polyuréthane et 30 MPa pour la mousse époxy en régime quasi-statique, et à 21 MPa pour la mousse polyuréthane et 72 MPa pour la mousse époxy lorsque la vitesse de déformation dépasse 104 s−1. Deux modèles physico-numériques sont développés pour représenter le comportement macroscopique de ces mousses à de telles vitesses de déformation. Les paramètres sont identifiés à partir des résultats d’expériences de compression dynamique (lanceur `a gaz, générateur de pression magnétique). La validité des modèles est testée en comparant les profils de vitesse calcul´es à l’aide d’un code dynamique explicite et les profils de vitesse mesurés lors des expériences. Ces modèles sont ensuite utilisés pour analyser les résultats obtenus lors d’expériences d’irradiation par faisceau d’électrons et de choc laser. Nous démontrons ainsi que les mousses polymères étudiées ont une forte capacité d’atténuation et que les modèles proposés sont valides à grande vitesse de déformation. / Polymeric foams are widely used in many industrial applications as thermal insulators, structural materials or shock mitigators. Indeed, they are light weight materials with an excellent weight /stiffness ratio and low production costs. One of the applications which interests the CEA is the protection of structures against mechanical loadings generated by laser irradiation or high velocity impact of small debris.The main objective of this PhD thesis is to investigate the mitigation capability of an expanded polyurethane foam and an epoxy syntactic foam against extremely fast (> 106 s−1) and intense(> 10 GPa) dynamic loadings. Cyclic quasi-static tests and dynamic experiments have been performed to investigate the behavior of these two foams for strain rates ranging from 10−3 to 106 s−1. Analysis of the experimental results shows that these polymeric foams have an elastic behavior phase followed by a compaction phase with significant permanent sets. Compaction thresholds are about 9 MPa for the polyurethane foam and 30 MPa for the epoxy foam under quasi-static loadings and around 21 MPa for the polyurethane foam and 72 MPa for the epoxy foam for strain rates above 104 s−1.Two porous compaction models are developed to represent the macroscopic behavior of these foams for such strain rates. The parameters are identified from the results of dynamic compression experiments (gas gun, low inductance generator). The validity of the models is tested by comparing calculated velocity profiles with an explicit hydrocode and velocity profiles measured during the experiments. These models are then used to analyze the results obtained with electron beam irradiation and laser-driven shock experiments. We demonstrate that the studied polymeric foam shave high mitigation capabilities and that the models are valid for high strain rates.
33

Fracture analysis of glass microsphere filled epoxy resin syntactic foam

Young, Peter, Aerospace, Civil & Mechanical Engineering, Australian Defence Force Academy, UNSW January 2008 (has links)
Hollow glass microspheres have been used extensively in the automotive and marine industries as an additive for reducing weight and saving material costs. They are also added to paints and other materials for their reflective properties. They have shown promise for weight critical applications, but have thus far resulted in materials with low fracture toughness and impact resistance when combined with thermosetting resins in syntactic foam. The advent of commercially available microspheres with a wide range of crushing strengths, densities and adhesive properties has given new impetus to research into syntactic foam with better fracture behaviour. Current research suggests that the beneficial effects on fracture and impact resistance gained by the addition of solid reinforcements such as rubber and ceramic particles are not seen with the addition of hollow glass microspheres. The research presented in this paper has examined the mechanisms for fracture resistance in glass microsphere filled epoxy (GMFE) syntactic foams, as well as determined the effect microsphere crushing strength and adhesion strength has on the material???s fracture toughness. The flexural properties of various GMFE have also been determined. GMFE were manufactured with varying microsphere volume fraction up to 50%, and with variances in microsphere crushing strength and adhesion. The specimens were tested for Mode I fracture toughness in a three point single edge notched bending setup as described in ASTM D5045 as well as a three point flexural setup as described in ASTM D790-3. Fracture surfaces were inspected using scanning electron microscope imaging to identify the fracture mechanisms in the presence of microspheres. Results indicate a positive effect on fracture toughness resulting from new fracture areas created as tails in the wake of the microspheres in the fracture plane. Results also indicate a negative effect on fracture toughness resulting from weak microspheres or from interfacial disbonding at the fracture plane. These two effects combine to show an increase in GMFE fracture toughness as the volume fraction of microspheres is increased to between 10 ??? 20% volume fraction (where the positive effect dominates), with a reduction in fracture toughness as microspheres are added further (where the negative effect dominates).
34

Changes in the Syntactic Structure in Translations from English into Swedish

Craven-Bartle Peltola, Cecilia January 2001 (has links)
<p>The purpose of this essay is to study how the major syntactic structure is affected when a literary text is translated from English into Swedish. That is, to study what operations take place and the frequency of the different operations in a translation. The purpose is also to see how much the freedom of translation varies between different translators.</p>
35

Lexical Conceptual Structure and Generation in Machine Translation

Dorr, Bonnie J. 01 June 1989 (has links)
This report introduces an implemented scheme for generating target- language sentences using a compositional representation of meaning called lexical conceptual structure. Lexical conceptual structure facilitates two crucial operations associated with generation: lexical selection and syntactic realization. The compositional nature of the representation is particularly valuable for these two operations when semantically equivalent source-and-target-language words and phrases are structurally or thematically divergent. To determine the correct lexical items and syntactic realization associated with the surface form in such cases, the underlying lexical-semantic forms are systematically mapped to the target-language syntactic structures. The model described constitutes a lexical-semantic extension to UNITRAN.
36

Null and Overt Subjects in a Variable System: The Case of Dominican Spanish

Martinez-Sanz, Cristina 29 November 2011 (has links)
This dissertation investigates subject expression patterns in Dominican Spanish (DS). In this variety, the null subject constructions associated with Non-Caribbean Spanish co-exist with the widespread use of overt subjects, which are found in specific constructions that are either rare or unattested in other Spanish varieties. Interestingly, these structures co-exist in the Dominican grammar with the null subject constructions associated with Non-Caribbean Spanish. While subject expression has been studied in a number of Spanish dialects within the generative and the variationist paradigms, monolingual Dominican Spanish, to the best of my knowledge, has not been investigated in previous variationist work. This study covers this gap by examining a large corpus of spontaneous speech (N=6005) gathered in the capital city of Santo Domingo and a rural area in the northwestern Cibao region. Furthermore, in line with the cohesive approach to syntactic variation developed in recent work (Adger and Smith 2005), theoretical implications are drawn from quantitative results. The results obtained in this study show that null and overt subject patterns in DS are regulated by the same constraints that have been found relevant in previous variationist work, i.e. discourse-related factor groups and Person (Otheguy, Zentella and Livert, 2007). These results depart from previous work in that evidence for language change in progress has been found in subject position patterns, rather than in null and overt subject distribution. When this phenomenon is examined, urban, young, high-middle class and female speakers arise as the social groups leading grammatical restructuring. Quantitative and qualitative evidence is taken into account for testing previous syntactic-theoretical proposals on DS. Taking the cartographic approach to syntactic structure (Rizzi 1997) as a point of departure, it will proposed that multiple specifier positions are available within the TP and CP fields to host strong and weak subjects. This proposal, in turn, makes it possible to account for the Null Subject Parameter profile displayed by synchronic DS without resorting to competing grammars in the minds of the speakers.
37

Gender-based differences in learner English : A syntax study of Swedish high school students’ written production

Signell, Kim January 2012 (has links)
Female students have long had a perceived advantage over male students in second language ac-quisition. In Swedish schools, the girls have outperformed the boys in the subject of English since the end of the Second World War, but the female students’ edge over the male students has diminished considerably over time. This essay aims to find out if there are any differences in lin-guistic ability between the two genders. The study uses a T-unit based syntax analysis in order to quantify the level of syntactic maturity that Swedish high school students possess, using data drawn from the Uppsala Learner English Corpus. Furthermore, the study aims to research gen-der-based stylistic differences and risk-taking behavior in the student’s writing. The results show that there are differences in syntactic maturity between the genders, as the female students in junior high school and the male students in senior high school outperform their respective counterparts, particularly in the indices based on error-free T-units. In addition, there are also stylistic disparities, as the female students have a greater focus on personalized ac-counts in their writing and the male students in junior high school have a very sparse and concise style of writing. The conclusion is drawn that while there are differences in syntactic maturity between boys and girls, the syntactic indices cannot accurately display the sophistication of the students’ writing and consequently should only be used in conjunction with more qualitative measures. Finally, while the study is not able to discern risk-taking in the students’ writing, the author concludes that risk-taking is an important factor in second language acquisition, especially considering the fact that the Swedish curricula in junior and senior high school English have a strong focus on communicative competence.
38

Null and Overt Subjects in a Variable System: The Case of Dominican Spanish

Martinez-Sanz, Cristina 29 November 2011 (has links)
This dissertation investigates subject expression patterns in Dominican Spanish (DS). In this variety, the null subject constructions associated with Non-Caribbean Spanish co-exist with the widespread use of overt subjects, which are found in specific constructions that are either rare or unattested in other Spanish varieties. Interestingly, these structures co-exist in the Dominican grammar with the null subject constructions associated with Non-Caribbean Spanish. While subject expression has been studied in a number of Spanish dialects within the generative and the variationist paradigms, monolingual Dominican Spanish, to the best of my knowledge, has not been investigated in previous variationist work. This study covers this gap by examining a large corpus of spontaneous speech (N=6005) gathered in the capital city of Santo Domingo and a rural area in the northwestern Cibao region. Furthermore, in line with the cohesive approach to syntactic variation developed in recent work (Adger and Smith 2005), theoretical implications are drawn from quantitative results. The results obtained in this study show that null and overt subject patterns in DS are regulated by the same constraints that have been found relevant in previous variationist work, i.e. discourse-related factor groups and Person (Otheguy, Zentella and Livert, 2007). These results depart from previous work in that evidence for language change in progress has been found in subject position patterns, rather than in null and overt subject distribution. When this phenomenon is examined, urban, young, high-middle class and female speakers arise as the social groups leading grammatical restructuring. Quantitative and qualitative evidence is taken into account for testing previous syntactic-theoretical proposals on DS. Taking the cartographic approach to syntactic structure (Rizzi 1997) as a point of departure, it will proposed that multiple specifier positions are available within the TP and CP fields to host strong and weak subjects. This proposal, in turn, makes it possible to account for the Null Subject Parameter profile displayed by synchronic DS without resorting to competing grammars in the minds of the speakers.
39

The structure and use of collective numeral phrases in Slavic : Russian, Bosnian/Croatian/Serbian, and Polish

Kim, Hyoungsup 23 March 2011 (has links)
This dissertation investigates Slavic collective numerals and their syntactic structure from descriptive and structural perspectives on the basis of the operation Agree. The headedness of Slavic collective numeral phrases will be focused on with three Slavic languages: Russian, Bosnian/ Croatian/Serbian, and Polish. To analyze the semantic and morphosyntactic properties of Slavic collective numeral phrases, I adopted two important concepts proposed by Rappaport (2002, 2006): i) Minimal Lexical Representation (MLR) and ii) pre-valued abstract Quantitative Case (QC). MLR represents the semantic and formal features of nouns, which selectively combine with collective numerals, while the idea of QC can predict the heterogeneous and homogeneous patterns of case assignment. The presence of pre-valued abstract QC triggers heterogeneous morphosyntax, while the absence of QC triggers homogeneous morphosyntax. The spell-out forms of collective numerals are the direct result of morphological syncretic rules. In regard of the headedness of Slavic collective numeral phrases, this research claims that nouns are the heads of Slavic numeral phrases on the grounds that numerals, adjectives, and other modifiers agree with nouns, which functions as the locus of morphosyntax (Zwicky 1985). The use of collective numerals is determined by the properties of nouns. In each chapter, Slavic collective numerals will be analyzed from the three points of view: i) semantics, ii) morphology, and iii) syntax. Collective numerals can emphasize the meaning of collectivity, totality, and cohesiveness as an aggregate. BCS and Polish collective numerals strictly specify a group of mixed gender, while Russian does not. BCS is characterized by three different types of collective numerals: i) collective numeral substantives (dvojica ‘two’, trojica ‘three’, četvorica ’four’, petorica ’five’, etc.), collective numerals (dvoje ‘two’, troje ‘three’, četvoro ’four’, petoro ’five’, etc.), and collective numeral adjectives (dvoji (m.)/ dvoje (f.)/ dvoja (n.) ’two’, etc.). Moreover, indeclinability of numerals is one of the characteristics of BCS numerals. Polish has secondary gender, so-called virile marking, which does not apply to collective numerals. Polish collective numerals are strictly used to express a group of mixed gender. / text
40

Programinė įranga lietuviško sakinio sintaksinei struktūrai atvaizduoti grafu / Software to create a program that could form a graph of syntactic structure of Lithuanian sentence

Talutytė, Jurgita 11 June 2004 (has links)
At the present there is no software for Lithuanian language that could form the Lithuanian language structure necessary for translation of words from one language to another. The aim of this paper was to create a program that could form a graph of syntactic structure of Lithuanian sentence. For this purpose the algorithm that could make a graphical presentation of syntactic sentence structure of Lithuanian words sequence in sentence and syntactic structure of each word should be formed.

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