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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.
231

Modèle adaptatif d'activités pour les jeux ubiquitaires / Adaptive model of activities for ubiquitous video game

Francillette, Yannick 18 December 2014 (has links)
Les technologies et services mobiles font aujourd'hui partie de notre vie quotidienne grâce notamment aux ordiphones et ardoises numériques. Nous vivons actuellement la réalisation de la vision de Marc Weiser. Les fonctionnalités et les services rendus prennent le dessus sur les objets techniques. Dans cette thèse, nous nous intéressons à un type particulier d'applications informatiques: les jeux vidéo. Comme d'autres secteurs, les jeux vidéo doivent prendre en compte la révolution mobile, pour se réinventer et intéresser des joueurs. Cependant, les jeux sur support mobiles doivent faire face au problème du changement des conditions de jeu du joueur. Nous pouvons parler de contexte du joueur.L'objectif de cette thèse est de proposer un modèle pour la conception de jeu auto-adaptatif au contexte du joueur. Ce modèle doit être générique et permettre la création de jeux vidéo qui sont capables de modifier les activités et objectifs qu'ils proposent en fonction du contexte courant du joueur. Notre proposition se constitue de deux éléments clefs. Le premier consiste en un modèle générique des activités et des objectifs d'un jeu vidéo que nous avons appelé «composant de gameplay». Ce modèle est une formalisation du concept de boucle de jeu objectif, challenge, récompense. Ce modèle nous permet de représenter les objectifs et activités du jeu sous la forme d'un arbre. Le deuxième élément est un modèle de détection des arbres compatibles avec un contexte courant. Ce modèle se base sur des règles de contexte qui sont associées aux nœuds de l'arbre. Notre démarche consiste ensuite à vérifier que l'objectif représenté par la racine de l'arbre peut être atteint dans le contexte courant. Pour valider notre approche, nous avons réalisé une expérimentation en laboratoire. Nous avons également utilisé notre expérience sur l'utilisation des composants de gameplay dans un contexte industriel. / Nowadays, the technologies and mobiles services are a part of our daily life thanks to smartphones and tablet computers. Currently, we live the realisation of Weiser's vision. The features and services provided are more important than technical objects.In this thesis, we are interested in a kind of computer applications: video games. Like other sectors, video games have to deal with mobile revolution in order to reinvent themselves and to interest players. However, video games on mobiles devices have to deal with the variation of playing conditions. We can call these conditions the player's context.The main objective of this thesis is to propose a model for the design of games that are able to adapt to the player's context. This model has to be generic and allow the game to adapt the proposed activities and objectives to the current context.Our proposition has two main elements. The first one is a generic model of the activities and the objectives which are proposed by the game. We have called this model "gameplay component". It is a formalization of the objectif, challenge, reward game loop concept. It allows us to represent a game as a tree.The second element is a model for detecting game tree which are compatible with a defined context. This model is based on rules which are linked with the nodes of the game tree. Our approach consist of checking that the objective which is given by the root of the game tree can be reached in the current context.In order to valid our approach, we have conducted a laboratory experimentation. We have also used our experience about using of gameplay component in a industrial context in order to do a case study.
232

A geographically constrained molecular phylogeny of Panamanian Aechmea species (Bromeliaceae, subfamily bromelioideae)

Maher, Keri Renee 01 January 2007 (has links)
This study lends strong support to the idea that members of Bromeliaceae have undergone a recent adaptive radiation, and therefore show that, at least in part, diversity in the tropics is due to a fast speciation rate and that the tropics can be a "cradle" for new diversification and exploitation of varying ecological niches through the diversification of ecophysiological traits within a lineage.
233

Perceptions of barriers to climate change adaptation by Uppsala farmers

Saritas, Alan January 2019 (has links)
Current emissions are likely to produce substantial impacts for the agricultural sector and the salience for adapting to these changes in the agricultural sector is increasing. While Nordic agriculture is faced with both opportunities and challenges from climate change, a still developing political and institutional structure in combination with an extreme drought during the summer of 2018 is exacerbating existing long-term trends of financial pressure in the sector, particularly for meat and dairy farmers. Previous research has highlighted that there is a relative lack of studies attempting to understand the decision-making process of climate change adaptation and there is a currently a growing field of research focusing on the barriers to adaptation faced by farmers. This study primarily used Grothmann and Patt’s MCCAPP model in order to determine what factors influenced farmers decision-making when deciding to adapt to climate change. The results of this study found that the predominant barrier to adaptation among farmers were uncertainty regarding future climatic impacts, which resulted in a lower confidence in adaptation strategy efficacy to produce financial stability and returns. Climate mitigation was also identified as a potential trade-off when pursuing adaptation strategies. To a lesser degree, farmers also attested to farm-level differences, such as the availability of water resources as impacting the strategies that they were able to pursue. Opportunities to facilitate adaptation through institutional support was identified, as farmers both require better information regarding adaptation strategies and subsequent trade-offs and synergies it might create in relation to farmers priority issues such as financial viability and climate mitigation. More effective means of financial assistance to counteract the effects of extreme climatic conditions was also identified. Lastly, social capital was an important facilitator of adaptation implementation, but one that is threatened due to the continuingly deteriorating socio-economic conditions that farmers experience in their sector.
234

Constrained and limited: understanding what makes adaptation challenging

Theokritoff, Emily 21 September 2023 (has links)
Der erste Teil dieser Arbeit konzentriert sich auf die systematische Synthese von Informationen über Anpassung, Anpassungsstrategien, Einschränkungen und Grenzen auf globaler Ebene durch die Aufarbeitung der wissenschaftlichen Literatur und mit Hilfe von Techniken des maschinellen Lernens. In einem zweiten Schritt werden mittels einer Online-Umfrage und halbstrukturierter Interviews die Wahrnehmungen von Einschränkungen der Anpassungsmöglichkeiten in den kleinen Inselstaaten der Karibik bewertet, wobei der Schwerpunkt auf den Wechselwirkungen zwischen verschiedenen Arten von Einschränkungen und dem erheblichen Einfluss der fehlenden Anpassungsfinanzierung liegt. Schließlich wird ein zukunftsorientierter Ansatz verfolgt, bei dem Bottom-up- und Top-down-Daten kombiniert werden, um zu veranschaulichen, wie sich sozioökonomische Dimensionen im Zusammenhang mit Einschränkungen bis zum Jahr 2100 unter verschiedenen Szenarien der künftigen sozialen und wirtschaftlichen Entwicklungen entfalten könnten. Die Ergebnisse zeigen, dass die Anpassung derzeit schrittweise und weitgehend fragmentiert erfolgt. Die Erkenntnisse über die Anpassungspolitik nehmen rasch zu, aber es bestehen weiterhin geografische Ungleichheiten. Finanzen und Regierungsführung sind weltweit die größten Einschränkungen, wobei die kleinen Inselstaaten sowie Mittel- und Südamerika die meisten Einschränkungen und Grenzen melden. Die Wechselwirkungen zwischen den Einschränkungen können zu Grenzen und zusätzlichen Verlusten und Schäden führen. Dies unterstreicht die Notwendigkeit, die Einschränkungen parallel anzugehen und eine nachhaltige und gezielte Anpassungsfinanzierung zu gewährleisten. Mögliche Szenarien für die künftige Entwicklung zeigen, dass selbst in den optimistischsten Szenarien sozioökonomische Schlüsseldimensionen wie schwache Regierungsführung die Anpassung bis weit in die zweite Hälfte des 21. Jahrhunderts hinein erschweren werden. / The first part of this thesis focuses on systematically synthesising information on adaptation, adaptation policies, constraints and limits on the global level by reviewing scientific literature and with the support of machine learning techniques. Secondly, through an online-survey and semi-structured interviews, perceptions of constraints in Caribbean Small Island Developing States are assessed, by focusing on the interactions between different types of constraints and the significant influence of the lack of adaptation finance. Finally, a forward-looking approach combining bottom-up and top-down data is taken to illustrate how socio-economic dimensions related to constraints could evolve by 2100, under various scenarios of future development. The results show that adaptation is currently incremental and largely fragmented. Evidence on adaptation policy is rapidly growing but geographic inequalities persist. There is negligible data on adaptation reducing climate change risks. Finance and governance are found to be the most prominent constraints globally, with Small Island Developing States and Central and South America reporting most constraints and limits. Indeed, Caribbean Small Island Developing States face large financial constraints which in turn closely interact with governance, human capacity and information constraints and result in vicious circles. Interactions between constraints can lead to limits and additional losses and damages. This highlights the need to address constraints in parallel and for sustained and dedicated adaptation finance. Potential scenarios of future development show that, even under the most optimistic scenarios, key socio-economic dimensions such as weak governance will challenge adaptation well into the second half of the 21st century. The persistence of constraints, in particular in the most vulnerable regions, calls for stringent mitigation, improved adaptation and increased efforts to address losses and damages.
235

An interaction framework for multiagent systems

Miller, Matthew James January 1900 (has links)
Doctor of Philosophy / Department of Computing and Information Sciences / Scott DeLoach / A multiagent system is a system that is composed of multiple autonomous agents. Au- tonomous agents are given the right and the responsibility to make decisions based on their perceptions and goals. Agents are also constrained by their capabilities, the environment and the system with which they reside. An agent within the system may need to coordinate with another agent in the system. This coordination may allow the agent to give updates from sensor readings, communicate updated map information or allow the agent to work on a cooperative task such as lifting an object. To coordinate agents must be able to communicate with one another. To communicate agents must have a communication medium. The medium is the conduit through which the information flows. Additionally there must be a set of rules to govern which agent talks at what time. This set of rules is called a communication protocol. To effectively and efficiently communicate all agents participating in the communication must be using compatible protocols. Robotic agents can be placed in diverse environment and there are multiple avenues for communication failure. Current multiagent systems use fixed communication protocols to allow agents to interact with one another. Using fixed protocols in an error prone environ- ment can lead to a high rate of system failure. To address these issues, I propose that a formal framework for interaction be defined. The framework should allow agents to choose new interaction protocols when the current protocol they are using fails. A formal framework allows automated tools to reason over the possible choices of interaction protocols. The tools can enumerate the protocols that will allow the agent to achieve its desired goal.
236

Building muscle : a translation of training adaptation / Bygga muskler : en översättning av träningsanpassning

Boman, Niklas January 2016 (has links)
Training is preparation for what is expected to come through utilization of the plastic and resistive features of nature, known as adaptation. As such, training in humans may have a number of desired goals. These are typically related to sports performance or education. Whatever the goal, a plan needs to be made for reaching it. One needs to identify or select which activities and environments constitute the event or events to which adaptation is sought. Adaptations occurs by imposing something similar to said environment and practicing the selected activities in preparation for the events that can ultimately lead to goal fulfillment. One quite common goal of physical training is to achieve a more lean and muscular physique, be it for reasons of performance or esthetics. A leaner and more muscular physique can have many advantages for health and quality of life. If we are to prepare the body’s physical capabilities and properties, they should be utilized in the preparation. By proper design and execution of a program for physical preparation, we set out on the path to achieve the goal. A factor that is often highlighted as an important key to building muscle in the human body is the steroid hormone testosterone. According to the hormone hypothesis, increases in muscle mass are achieved through transient elevations in anabolic hormones, such as testosterone and IGF1, induced by physical training. To achieve hypertrophy of the muscles through physical training, one must ensure sure that the muscles get the correct signal, the growth signal, as a result of the training. The work presented in this thesis is, in part, an examination of the hormone hypothesis, with both empirical and theoretical elements. The empirical foundations are results of an experiment in which a group of young men were subjected to a program of physical training, designed for all intents and purposes in accordance with contemporary knowledge, to result in muscular hypertrophy in the subjects. The goal was achieved, with an average 4.6% increase in lean body mass in the subjects after the training program. However, there was no evidence that anabolic hormones were elevated at any time during the measurement period. The major part of this thesis details a model for explaining the collected observations. It is not intended to merely provide a guide for achieving a leaner more muscular physique but rather is aimed at formulating the problem of inducing the desired adaptations and difficulties involved in approaching the problem. For reasons discussed in this thesis, I do not claim that this is the full and final word on the matter. However, it goes some way toward explaining why, and perhaps how, desired goals should be formulated so that the muscles may understand them.
237

Le rôle et l'influence de la relation élève-enseignant sur l'adaptation scolaire et sociale des élèves dans les écoles primaires québécoises

Valencia, Alejandra January 2010 (has links)
Cette étude explore pour la première fois auprès d'une population québécoise le lien existant entre la qualité de la relation élève-enseignant (REE) et l'adaptation scolaire d'élèves ayant un trouble du comportement. La qualité du lien affectif des 80 élèves participants est étudiée sous l'angle de la théorie de l'attachement et mesurée à l'aide du STRS (Student-Teacher Relationship Scale) ainsi que du TSRI (Teacher-Student Relationship Inventory). Des analyses de corrélation font ressortir de nombreux liens entre la qualité de la REE et les variables d'adaptation scolaire utilisées: la compétence académique (notes et habitudes de travail), les habiletés sociales/ appréciation par les pairs, les problèmes de comportement extériorisés, puis finalement, la motivation/satisfaction scolaire de l'élève. De plus, la qualité de la REE en fin d'année scolaire a été comparée selon la fréquentation de l'élève à l'un ou l'autre des services: 1) des classes spéciales traditionnelles (N=30) et 2) des classes kangourou, dont la philosophie est axée sur l'établissement d'une REE positive (N=50). Les résultats de cette comparaison indiquent peu de différence significative dans l'évolution des élèves selon les deux services et pas de différence au niveau de la qualité de la REE pour cet échantillon.
238

Characterisation of the mechanism of human serum resistance in Trypanosoma brucei gambiense.

Felu, Cécile 15 September 2006 (has links)
The two human pathogenic sub-species T.b.gambiense and T.b.rhodesiense can be distinguished from the morphologically identical T.b.brucei by their ability to infect humans, enabling them to cause sleeping sickness. This is because they are resistant to lysis by the lytic factor (APOL-I) present in normal human serum (NHS). In T.b.rhodesiense resistance to this lytic factor is due to a truncated VSG gene termed SRA which blocks lysis by interacting with APOL-I in the lysosome. SRA does not exist in T.b.gambiense. The search for a similar truncated VSG gene lead to the identification of a T.b.gambiense specific glycoprotein termed TGSGP. TGSGP transfected alone into the sensitive T.b.brucei is unable to confer resistance to this sub-species. This is either due to incorrect processing of this gene is this sub-species or because TGSGP requires a partner to confer resistance. In the search for a partner, the genomic locus of TGSGP was cloned and sequenced. We found that TGSGP is linked to a truncated gene homologous to the S.cerevisiae AUT1 gene, a gene implicated in autophagy and more specifically in membrane expansion. Southern blot hybridization and PCR analysis on genomic DNA from several isolates demonstrated that this feature was a specific to T.b.gambiense. In addition, we observed a correlation between the aut1 allele size and the geographical origin of the isolate. Since in trypanosomes lysis by NHS is due to an uncontrolled expansion of the lysosome, we speculated that the truncation of the aut1 allele could be implication in the resistance to human serum. We characterized the genomic organisation of the AUT1 locus. T.b.brucei possesses two native AUT1 alleles whilst T.b.gambiense possesses a truncated aut1 allele, as well as a native AUT1 allele. We showed that in the T.b.gambiense LiTAR isolate (aut1/AUT1), despite the presence of a wild-type allele this gene is no longer expressed at the mRNA and protein level. Our complimentary results by run-on transcription assay showed that the AUT1 region is transcribed but that the messenger is unstable. LiTAR is a functional knock-out for AUT1, but Northern blot analysis on several T.b.gambiense isolates showed that this is not a generalised T.b.gambiense characteristic. We explored the role of AUT1 in trypanosomes by invalidation of the AUT1 gene in T.b.brucei and by the over-expression of the AUT1 and aut1 alleles in T.b.brucei. By functional analysis of AUT1 knocked-down cells we showed that AUT1 is not essential in trypanosomes. By recreating in T.b.brucei the T.b.gambiense AUT1/aut1 genotype we were able to show that the expression of the aut1 UTR down-regulated the expression of the wild-type AUT1 allele. We speculated that this may be due to a natural RNAi mechanism. Par northern blot, using probes covering the potential target region of AUT1, we detected a 50nt small RNA specific to T.b.gambiense. In addition, we showed that in a LiTAR strain in which the RNAi pathway was abolished AUT1 expression is restored. We continued to investigate TGSGP’s role in the resistance to human serum by invalidation of TGSGP in T.b.gambiense and by expressing TGSGP in the NHS-sensitive T.b.brucei. Because T.b.gambiense cannot be cultured in vitro we established a new in vivo transfection technique and as the knock-out of TGSGP is most probably lethal, we created an inducible RNAi T.b.gambiense cell strain. These indispensable tools will be used to test whether invalidation TGSGP is sufficient to confer resistance to NHS. Many strategies were tested in order to correctly expressing TGSGP in T.b.brucei; in none of these transfectants was TGSGP correctly located in the flagellar pocket as is the case in T.b.gambiense and only partial resistance was ever obtained. In order to identify the factors in human serum that could interacts with TGSGP, we subjected NHS to affinity chromatography using TGSGP as bait. We showed that TGSGP interacts with APOA-I, a major component of HDLs.
239

Infusion of Information Systems: The Role of Adaptation and Individual Cognitions

Fadel, Kelly John January 2007 (has links)
Each year, organizations invest billions of dollars in large information systems (IS) that support business processes. These systems are implemented with the hope that they will bring increased efficiency and productivity to operations, decision making, and collaboration, thus strengthening competitive advantage in an increasingly aggressive global marketplace. Unfortunately, empirical evidence demonstrates that despite prodigious investment in these systems, their purported benefits often lag behind expectations, or fail to materialize at all. While many causes may contribute to these failures, a common theme in empirical studies is that information systems are rarely infused into individuals' work practices, thus undermining their benefits to the organization. IS infusion refers to the degree to which the technology is fully integrated into an individual's or organization's work systems. Although theoretical and practical interest in IS infusion is growing, little is understood about the factors that lead to IS infusion at the individual level.This dissertation integrates research and theory in information systems acceptance, adaptation, and infusion to develop a theoretical model of IS infusion at the individual level. To test the model, a survey instrument was developed and tested at the health care facility of a large public university. The revised survey was then deployed at a large technology firm in the northwestern United States, from which 195 individual responses were obtained. Results indicate that adaptation behaviors engaged in by IS users significantly impact the degree to which they infuse the IS in their work. Moreover, these adaptation behaviors are shaped by cognitive appraisals of the IS, which are, in turn, influenced by key acceptance-related IS perceptions.This study contributes to research by integrating previously disparate theories into a holistic framework of individual-level IS infusion. For practice, this research sheds light on specific factors that contribute to IS adaptation and infusion, thereby assisting IS managers to promote these outcomes within their organization.
240

Assessing drought vulnerability

Abraham, Joseph January 2006 (has links)
This dissertation makes valuable contributions to hazard and disaster vulnerability assessment theory and methodology. Appendix A presents results of a national survey of state drought planning processes that examined and evaluated how state processes were assessing drought impacts and vulnerabilities, and how assessments were used to mitigate risk. While impact and vulnerability assessments have been useful for reactive, short-term mitigation, most were found to have not been used to develop pro-active and/or committed, long-term mitigation programs. To be useful for developing long-term planning and mitigation, assessments must involve more social scientists, a greater emphasis on second-, third-, etc., order impacts, and examining how systems are sensitive to drought exposure, and studying adaptive capacity. Appendix B adapts a political economy/human ecology and political ecology research framework and examines how regional historical, institutional and regional development patterns in central Arizona have contributed to the production of local drought vulnerability in rural Arizona during the 20th century. The study evaluates the applicability of a research framework developed in Third World settings, and resulted in valuable insights for developing state and county policy in Arizona to mitigate social, economic, and political-institutional drivers of drought vulnerability. Appendix C compliments the assessment in Appendix B by examining local drivers of drought vulnerability and conducting a comparative drought vulnerability analysis in two rural communities in northern Gila County, Arizona. The assessment found local differences in community water system vulnerabilities were driven by differences in capacity to adapt to climate variability and population growth. Differences in adaptive capacity, in turn, were driven by differences in local management, institutional factors, and economic incentives of private and public water systems. Together, the three appendices contribute practical and theoretical contributions for assessments conducted by state and local governments, non-governmental organizations, and academic research units that seek to assess and ultimately mitigate hazard and disaster vulnerability.

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