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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.
281

Scorpio : une Approche d'Adaptation Structurelle de Composants Logiciels - Application aux Environnements Ubiquitaires

Bastide, Gautier 12 December 2007 (has links) (PDF)
La réutilisation à grande échelle de composants logiciels se révèle être un challenge pour la conception de nouvelles applications. Dans la grande majorité des cas, pour être intégrés à une application, les composants disponibles ont besoin d'être adaptés afin de faire face à la multiplicité des environnements de déploiement dotés de caractéristiques variables. Ainsi, pour éviter le redéveloppement de nouveaux composants et favoriser la réutilisation, de nombreuses approches ont proposé des techniques permettant d'adapter le comportement de composants existants. Cependant, adapter le comportement de composants n'est pas suffisant pour permettre leur réutilisation : il faut également adapter leur structure. Or, aucune approche existante ne permet de répondre pleinement à ces besoins en adaptation structurelle. Ainsi, notre objectif est de proposer une approche, appelée Scorpio, permettant d'adapter la structure de composants. Nous nous focalisons plus particulièrement sur des composants existants. Dans un premier temps, nous nous sommes intéressés à l'adaptation structurelle de composants existants en proposant un processus permettant leur ré-ingénierie vers de nouvelles structures. Puis, pour répondre aux besoins liés à une adaptation sans interruption de l'exécution, nous avons proposé des mécanismes permettant de prendre en charge l'adaptation dynamique de ces composants. Partant du constat qu'un certain nombre d'environnements, tels que les environnements ubiquitaires, nécessite une automatisation du processus d'adaptation, nous avons proposé alors de prendre en charge ces besoins à travers une approche permettant l'auto-adaptation structurelle de composants logiciels. Enfin, nos propositions ont été mises en œuvre d'une part par la réalisation du prototype Scorpio-Tool implémenté en Fractal et d'autre part, par la définition et le développement d'un scénario ubiquitaire permettant l'expérimentation de ces propositions.
282

En kvalitativ undersökning om infärgning ur matematiklärarens perspektiv. : Är infärgning den ultimata lösningen för ett G i matematik A för fordonselever?

Krutholm, Tommy January 2008 (has links)
<p>In this study the reader will learn how to work with student adaptation as a method for students to easier study and learn mathematics at a vocational school focusing on vehicle maintenance. This secondary school is located in the southern part of Sweden. Four math teachers who teach at this program use in-depth interview when it comes into explaining what they mean regarding adaptation and its role in teaching this students and helping them pass the course. This is very much a topic of today and has been so for some time. We hear about reports which reveals alarmingly low levels of know light which continue to drop especially at vocational programs in particular in mathematic. The math teachers describe specific obstacles and circumstances which in their experiences will limit their teaching options and alternatives and therefore will also limit the adaptation and its role. One may say in general that adaptation not necessarily is a method with an obvious template to follow so many various players will have to be involved in the teaching. This holds true with regards to all various aspects of learning. The student is here by enabled to see and experience the full picture of the program and the subject in question. No matter what the subject is, focus will always be the goal of the program and the students’ future careers. There are questions as to whether there may be conflicts of interest between the various actors involved in the learning process.</p><p>.</p>
283

A comparative analysis of morphological, physiological, and biochemical adaptation to abiotic stress in intertidal porcelain crabs, genus Petrolisthes

Stillman, Jonathon Harris 04 December 1998 (has links)
Organismal tolerance to abiotic environmental stresses contributes significantly to setting the distribution limits of organisms, as demonstrated by vertical zonation patterns in the marine intertidal zone. In this thesis, the ultimate (evolutionary) and proximate (mechanistic) causes of tolerance to temperature and emersion stresses associated with the intertidal zone were examined using porcelain crabs, genus Petrolisthes. Species of Petrolisthes from intertidal and subtidal microhabitats of four biogeographic regions of the Eastern Pacific were used in phylogenetically-based comparative analyses of morphological, physiological, and biochemical adaptation to environmental stress. A phylogenetic tree based on the sequence of the 16sRNA gene was developed to facilitate these analyses. Organismal thermal tolerance limits are adapted to match maximal microhabitat temperatures. Acclimation of thermal tolerance limits suggests that temperate intertidal zone species are living close to their thermal maximum in nature. Respiratory responses to emersion vary among species from different vertical zones. Experimental examination of oxygen consumption rates and lactate accumulation during emersion suggests that intertidal species are able to respire in air using thin membranous regions on the ventral meral segments of their legs (leg membranes). Leg membrane size is positively correlated with body size across species, but not within a single species. Evolutionary analyses indicate that leg membranes may not have evolved for purposes of aerial respiration, but their presence may have allowed intertidal and subtidal species to achieve larger body sizes and higher metabolic rates. The thermal stabilities of an enzyme, lactate dehydrogenase (LDH), from 22 species of Petrolisthes varied widely, but were not correlated with maximal habitat temperatures. Comparative analyses did not indicate any evolutionary relationship between LDH thermal stability and microhabitat conditions. Experimental evidence suggests that interspecific differences in LDH stability are genetically based, and are due both to intrinsic properties of the LDH molecules and extrinsic protein stabilizers. Elucidation of the mechanism(s) of LDH stabilization in Petrolisthes may provide novel insight to the field of protein stabilization. These results studies suggest that individual traits may be subjected to differing levels of selection, and thus the analysis of environmental adaptation requires careful consideration of the biological significance of the traits being examined. / Graduation date: 1999
284

Upper limb cooling : the effects of gender and 5 day cold acclimation on strength, manual performance and perception /

Powell, Michael Edward Scott. January 2004 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 2005. / Restricted until May 2006. Includes bibliographical references.
285

Women's positive adaptation in childhood and adulthood : A longitudinal study

Andersson, Håkan January 2007 (has links)
An area within psychology that looks at the strengths and positive sides of human life has emerged the last decade. It is called positive psychology and one area related to that is positive adaptation. The main purpose of this paper is to describe the natural history of females’ positive extrinsic and intrinsic adaptation from childhood to adulthood, with a focus on typical positive patterns of adaptation and how these patterns develop within the same individual. The sample consisted of about 500 Swedish girls and data were taken at age 13, 15, and 43 from the longitudinal research program Individual Development and Adaptation (IDA). Variable-oriented methods were used to study basic relationships among factors both within age and between childhood and adulthood and person-oriented methods were used to study typical patterns of adaptation and how these patterns develop, using cluster analyses and cross-tabulation of clusters. The overall results show, as expected, more distinct typical positive adaptation patterns in the intrinsic than the extrinsic area in both childhood and adulthood. Significant longitudinal developmental streams between typical positive adaptation patterns in childhood and adulthood were found and these are discussed from a dynamic system perspective suggesting the interaction between factors thru reinforcing feedback processes.
286

En kvalitativ undersökning om infärgning ur matematiklärarens perspektiv. : Är infärgning den ultimata lösningen för ett G i matematik A för fordonselever?

Krutholm, Tommy January 2008 (has links)
In this study the reader will learn how to work with student adaptation as a method for students to easier study and learn mathematics at a vocational school focusing on vehicle maintenance. This secondary school is located in the southern part of Sweden. Four math teachers who teach at this program use in-depth interview when it comes into explaining what they mean regarding adaptation and its role in teaching this students and helping them pass the course. This is very much a topic of today and has been so for some time. We hear about reports which reveals alarmingly low levels of know light which continue to drop especially at vocational programs in particular in mathematic. The math teachers describe specific obstacles and circumstances which in their experiences will limit their teaching options and alternatives and therefore will also limit the adaptation and its role. One may say in general that adaptation not necessarily is a method with an obvious template to follow so many various players will have to be involved in the teaching. This holds true with regards to all various aspects of learning. The student is here by enabled to see and experience the full picture of the program and the subject in question. No matter what the subject is, focus will always be the goal of the program and the students’ future careers. There are questions as to whether there may be conflicts of interest between the various actors involved in the learning process. .
287

Anisotropic adaptation: metrics and meshes

Pagnutti, Douglas 05 1900 (has links)
We present a method for anisotropic mesh refinement to high-order numerical solutions. We accomplish this by assigning metrics to vertices that approximate the error in that region. To choose values for each metric, we first reconstruct an error equation from the leading order terms of the Taylor expansion. Then, we use a Fourier approximation to choose the metric associated with that vertex. After assigning a metric to each vertex, we refine the mesh anisotropically using three mesh operations. The three mesh operations we use are swapping to maximize quality, inserting at approximate circumcenters to decrease cell size, and vertex removal to eliminate small edges. Because there are no guarantees on the results of these modification tools, we use them iteratively to produce a quasi-optimal mesh. We present examples demonstrating that our anisotropic refinement algorithm improves solution accuracy for both second and third order solutions compared with uniform refinement and isotropic refinement. We also analyze the effect of using second derivatives for refining third order solutions.
288

Adaptation/Standardization of SMEs’ Marketing Mix Elements across borders

Valassis, Kostantin, de Rosen, Yannick January 2013 (has links)
Nowadays, the globalization phenomena makes companies of every size think beyond domestic market. However, implement an international strategy that is efficient is not a simple task for firms. Indeed, companies have to respond to market specific context while they have different characteristics. In the literature, with regard to the adaptation/standardization of the marketing mix, most of the researches have built their theories upon the analysis of multinationals’ cases. Little attention has been paid on the cases of SMEs although in different topics of interest it has been seen that these two types of companies do not behave exactly the same ways. Therefore, this thesis aims to find the reasons affecting the SME’s decision of adapting/standardizing the marketing mix and how do they proceed to do so. A qualitative research has been done with one Belgian small-medium enterprise (Bruyere) that evolves in the chocolate industry and more precisely in the market of pralines. The data gathered, thanks to the interview of two managers of Bruyerre, are structured with the theoretical framework beforehand developed. The analysis and discussion section contrasts and compares the theoretical framework and the data gathered. The research brought specific and significant findings about the small-medium Belgian enterprise (Bruyerre). Beyond general factors affecting their decisions either to adapt or standardize the element of the marketing mix strategy across nations, in this case, we found that managers have to build strong relationships with their partners across nations, take into consideration the nature of their product when deciding the strategy of adaptation/standardization and be flexible for their partners’ requests.
289

Evolutionary and Physiological Adaptation of Pseudomonas aeruginosa to Elevated Concentrations of Sodium Chloride

Taha, Mariam 23 November 2011 (has links)
I have investigated the evolutionary response of Pseudomonas aeruginosa to salt (NaCl) stress, and the physiological mechanisms responsible for this adaptation. Populations of P. aeruginosa founded from the same ancestral genotype were selected at three different concentrations of NaCl, low, moderate and high for about 660 generations with four independent replicates for each concentration. Adaptation was measured as the fitness of the evolved populations relative to the ancestor assessed in direct, head-to-head competition experiments conducted in the same environment in which they were selected (direct response) as well as in all alternative environments (correlated response). Results suggest that selection in each salt environment led to adaptation to that environment and a modest degree of specialization that evolved because correlated responses to selection were smaller than direct responses. In order to identify the physiological mechanisms contributing to the populations' adaptation in high NaCl concentration, I chose a sample of evolved lines that showed the strongest evidence for specialization to salt and competed them against the common ancestor in KCl and sucrose. Results suggested that increased Na+ /H+ antiporter activity is probably the primary mechanism behind adaptation to high NaCl concentration, however alternative mechanisms cannot be excluded. Tolerance curves, which measure the performance of a genotype across a gradient of salt concentrations, suggested no change in the high salt group’s ability to tolerate extreme concentrations of NaCl. We conclude that high salt evolved population showed improvements to its ionic/osmotic stress resistance strategies mainly to Na+ efflux strategies but with no changes to salt niche.
290

Identification of Mutations in the NS1 Gene That Control Influenza A Virus Virulence in the Mouse Model

Dankar, Samar 03 October 2012 (has links)
The genetic requirements for Influenza virus to infect and adapt to new species is largely unknown. To understand the evolutionary steps required by a virus to become virulent, a human virus (A/HK/1/68) (HK), avirulent in mice, was subjected to 20 and 21 serial lung-to-lung passages in mouse. Sequence analysis revealed the emergence of eleven mutations within the NS1 gene of the new virulent strains, many of which occurred in binding sites for transcriptional and translational cellular factors. In the present study we have rescued viruses containing each of the NS1 mouse adapted mutations onto A/PR/8/34 (PR8) backbone. We found 9 of 16 NS1 mutants were adaptive by inducing mortality, body weight loss in BALB/c mice and enhanced virus replication in MDCK cells with properties of host cell interferon transcription inhibition. Sequence comparisons with the highly pathogenic A/Hong Kong/156/1997 (H5N1) and the most severe pandemic A/Brevig Mission/1/1918 (H1N1) NS1 genes showed convergent evolution with some of the mouse adapted viruses for F103L plus M106I and V226I plus R227K mutations respectively. The F103L and M106I mutations in the HK NS1 gene were shown to be adaptive by assessment with respect to replication, early viral protein synthesis, interferon-β antagonism and tropism in the mouse lung. We extended the study and proved increased virulence associated with F103L+M106I mutations in their respective H5N1 NS1 gene on the PR8 and HK backbones, as well as the PR8 NS1 gene and the H9N2 (A/Ck/Bj/1/95) gene in the PR8 and A/WSN/33 backbones respectively. However the V226I and R227K mutations in their respective HK and 1918 NS1 genes slightly enhanced virulence and viral growth at later stages of infection. This study demonstrates that NS1 is a virulence factor; involved in multiple viral processes including interferon antagonism and viral protein synthesis. Furthermore, NS1 mutations acquired during mouse adaptation are proven to be adaptive in human, mouse and avian NS1 genes.

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