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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

Grey Owl, les autochtones et la perception environnementale au Canada au début du XXe siècle / Grey Owl, les autochtones et la perception environnementale au Canada au début du 20e siècle / Grey Owl, les autochtones et la perception environnementale au Canada au début du vingtième siècle

Sähr, Sylvia 12 April 2018 (has links)
À travers l’analyse du discours environnemental de l’auteur et conférencier Grey Owl (1888 – 1938), ce mémoire constitue une étude de la perception environnementale des cultures autochtones et occidentales au Canada au début du XXe siècle. L’objectif est d’identifier la perception environnementale dans sa dépendance de l’état de la Nature, de l’époque et de la culture de l’individu et de la société. Avant-gardiste, Grey Owl intégrait des éléments des concepts de mode de vie durable et d’écotourisme dans son discours. Il représentait également l’ambivalence des sociétés occidentales envers la Nature. Sans sa transformation en Autochtone, cet Anglais aux cheveux longs n’aurait pu faire connaître au grand public la nécessité de sauver la Wilderness et les cultures autochtones. Il a contribué à l’image romantique créée des Autochtones par des Occidentaux. Encore aujourd’hui, longtemps après la colonisation, les Autochtones, peuples chers à Grey Owl, ressentent une perte d’identité. / Through an analysis of the environmental discourse of the author and speaker Grey Owl (1888 – 1938), this thesis studies the environmental perception of Native and Western cultures in Canada in the early 20th century. The objective is to identify the environmental perception in its dependency of the state of Nature, the epoch and the culture of the individual and the society. Avant-gardist, Grey Owl integrated elements of a sustainable way of life and ecotourism in his discourse. He too represented the ambivalence of Western societies to the Nature. Without his transformation into a Native, this Englishman with his long hair could not have made known the necessity of saving the wilderness and the native cultures to a wide audience. He contributed to the romantic image created from the Natives by the Western societies. Still today, long after the colonization, the Natives, peoples dear to Grey Owl, feel a loss of identity.
72

The impact of increasing predation risk and declining food availability on the population dynamics and demography of a long-lived mesopredator

Hoy, Sarah Rose January 2015 (has links)
Understanding the role that extrinsic processes play in shaping animal population dynamics and demography is a central tenet of population ecology and an issue of vital importance for conservation and wildlife management. The top-down impact of predation and bottom-up influence of food availability are thought to be two of the most important extrinsic processes affecting population dynamics and demography of species occupying middle trophic levels. However, many studies only focus on quantifying the impact of one of these processes in isolation and it is not clear whether the impact of one extrinsic factor on population dynamics and demographic rates is augmented or lessened by changes in other extrinsic factors. In this thesis I examine the extent to which both top-down and bottom-up processes shape population dynamics (population size, recruitment and immigration) and demography (survival, reproduction, life-history trade-offs and reproductive strategies) in a long-lived species, the tawny owl, by taking advantage of a natural increase in predation risk (goshawk abundance) and a decline in food availability (field vole densities). Despite the increase in predation and the decline in food availability, the owl population remained stable, which we posit is due to goshawk predation being selective on individuals with a low reproductive value (juveniles and old individuals) and an increasing number of immigrants entering the population. Selective predation on older owls had a negative impact on the survival of this age class and appeared to be shaping the pattern of actuarial senescence and influencing the strength of the intrinsic trade-off between survival and reproduction. As food availability declined and predation risk increased owls appeared to be switching from an 'eggs in one basket strategy' of saving resources to invest more in fewer breeding attempts in the future, to a 'bet-hedging' strategy of reproducing more often, but investing less per breeding attempt.
73

Change in Migratory Behavior as a Possible Explanation for Burrowing Owl Population Declines in Northern Latitudes

Macias-Duarte, Alberto January 2011 (has links)
Recent observed changes in bird distributions provide an unprecedented opportunity to gain a deeper understanding of the processes that influence species' persistence. By modelling presence-absence data from the North American Breeding Bird Survey, we found evidence that the breeding range of the western burrowing owl has contracted at its northern, western, and eastern boundaries since 1967. We suggest that the species' breeding distribution is also expanding southwards to former wintering grounds into northern Mexico, facilitated by the appearance of new breeding habitat created by irrigated agriculture in the arid areas of southwestern United States and northwestern Mexico. This dissertation explores the hypothesis that burrowing owls from northern migratory populations have become resident breeders in areas of northwestern Mexico that were formerly used only by migratory owls during winter, contributing to both population declines near the northern extent of the species' breeding range and population increases in the southern half of the species' range. We used novel DNA microsatellite markers to test patterns of gene flow predicted by this migration-mediated range-shift hypothesis. We genotyped 1,560 owls from 36 study locations in Canada, Mexico, and the United States. Analyses of molecular variance provided evidence that burrowing owl populations in both northwestern Mexico and Canada are genetically different from the rest of the populations in the breeding range, lending some support to the migration-mediated range-shift hypothesis. We found evidence of subtle genetic differentiation associated with subtropical irrigated agricultural areas in southern Sonora and Sinaloa, demonstrating that land use can produce location-specific population dynamics leading to genetic structure even in the absence of dispersal barriers. We also used stable isotopes 2/H, 13/C, and 15/N in feathers to test philopatry and breeding dispersal patterns predicted by this migration-mediated range-shift hypothesis. Burrowing owl populations near the northern edge of the species' breeding range had a high proportion of immigrants compared to interior populations, while other populations had high levels of philopatry. Stable isotopes also provided evidence of breeding dispersal events from Canadian populations to northwestern Mexico in support of the migration-mediated range-shift hypothesis, but similar isotope signatures in nestling feathers between these two regions prevent stronger inferences.
74

SUMMER HABITAT AND NEST SITE SELECTION OF ELF OWLS (MICRATHENE WHITNEYI) AT SAGUARO NATIONAL MONUMENT, ARIZONA (SONORAN-DESERT, HABITAT USE).

Goad, Mary Susanna. January 1985 (has links)
No description available.
75

Contributions à l'alignement d'ontologies OWL par agrégation de similarités / Contributions to OWL ontologies alignment using similarity aggregation

Zghal, Sami 21 December 2010 (has links)
Dans le cadre de cette thèse, nous avons proposé plusieurs méthodes d'alignement à savoir: la méthode EDOLA, la méthode SODA et la méthode OACAS. Les trois méthodes procèdent dans une première phase à la transformation des deux ontologies à aligner sous la forme d'un graphe, O-Graph, pour chaque ontologie. Ces graphes permettent la représentation des ontologies sous une forme facile à l'exploitation. La méthode EDOLA est une approche se basant sur un modèle de calcul des similarités locale et globale. Ce modèle suit la structure du graphe pour calculer les mesures de similarité entre les noeuds des deux ontologies. Le module d'alignement associe pour chaque catégorie de noeuds une fonction d'agrégation. La fonction d'agrégation prend en considération toutes les mesures de similarités entre les couples de noeuds voisins au couple de noeud à apparier. La méthode SODA est une amélioration de la méthode EDOLA. En effet, la méthode SODA opère sur les ontologies OWL-DL, pour les aligner, à la place des ontologies décrites en OWL-Lite. La méthode SODA est une approche structurelle pour l'alignement d'ontologies OWL-DL. Elle opère en 3 étapes successives. La première étape permet de calculer la similarité linguistique à travers des mesures de similarité plus adaptées aux descripteurs des constituants des ontologies à apparier. La seconde étape détermine la similarité structurelle en exploitant la structure des deux graphes O-Graphs. La troisième étape déduit la similarité sémantique, en prenant en considération les deux types de similarités déjà calculées. La méthode d'alignement, OACAS, opère en 3 étapes successives pour produire l'alignement. La première étape permet de calculer la similarité linguistique composée. La similarité linguistique composée prend en considération tous les descripteurs des entités ontologiques à aligner. La seconde étape détermine la similarité de voisinage par niveau. La troisième étape agrège les composants de la similarité linguistique composée et la similarité de voisinage par niveau pour déterminer la similarité agrégée. / In this thesis, we have proposed three ontology alignment methods: EDOLA (Extended Diameter OWL-Lite Alignment) method, SODA (Structural Ontology OWL-DL Alignment) method and OACAS (Ontologies Alignment using Composition and Aggregation of Similarities) method. These methods rely on aggregation and composition of similarities and check the spread structure of the ontologies to be aligned. EDOLA method allows to align OWL-Lite ontologies whereas SODA and OACAS consider OWL-DL ontologies. The three proposed methods operate in a first step by transforming both ontologies to aligned as a graph, named O-Graph, for each ontology. This graph reproduces OWL ontologies to be easily manipulated during the alignment process. The obtained graphs describe all the information contained in the ontologies: entities, relations between entities and instances. Besides, the EDOLA method is a new approach that computes local and global similarities using a propagation technique of similarities through the O-Graphs. This model explores the structure of the considered O-Graphs to compute the similarity values between the nodes of both ontologies. The alignment model associates for each category of nodes an aggregation function. This function takes in consideration all the similarity measures of the couple of nodes to match. This aggregation function explores all descriptive information of this couple. EDOLA operates in two succesive steps. The first step computes the local similarity, terminological one, whereas the second step computes the global one. The SODA method is an improved version of EDOLA. In fact, it uses OWL-DL ontologies. SODA method is a structures approach for OWL-DL ontologies. The method operates in three successive steps and explores the structure the ontologies using O-Graphs. The first step computes linguistic similarity using appropriate similarity measures corresponding to the descriptors of ontological entities. The second step allows to compute structural similarity using the two graphs O-Graphs. The third step deduces the semantic similarity, by combining both similarities already computed, in order to outperform the alignment task.
76

An Ontology Centric Architecture For Mediating Interactions In Semantic Web-Based E-Commerce Environments

Thomas, Manoj 07 March 2008 (has links)
Information freely generated, widely distributed and openly interpreted is a rich source of creative energy in the digital age that we live in. As we move further into this irrevocable relationship with self-growing and actively proliferating information spaces, we are also finding ourselves overwhelmed, disheartened and powerless in the presence of so much information. We are at a point where, without domain familiarity or expert guidance, sifting through the copious volumes of information to find relevance quickly turns into a mundane task often requiring enormous patience. The realization of accomplishment soon turns into a matter of extensive cognitive load, serendipity or just plain luck. This dissertation describes a theoretical framework to analyze user interactions based on mental representations in a medium where the nature of the problem-solving task emphasizes the interaction between internal task representation and the external problem domain. The framework is established by relating to work in behavioral science, sociology, cognitive science and knowledge engineering, particularly Herbert Simon’s (1957; 1989) notion of satisficing on bounded rationality and Schön’s (1983) reflective model. Mental representations mediate situated actions in our constrained digital environment and provide the opportunity for completing a task. Since assistive aids to guide situated actions reduce complexity in the task environment (Vessey 1991; Pirolli et al. 1999), the framework is used as the foundation for developing mediating structures to express the internal, external and mental representations. Interaction aids superimposed on mediating structures that model thought and action will help to guide the “perpetual novice” (Borgman 1996) through the vast digital information spaces by orchestrating better cognitive fit between the task environment and the task solution. This dissertation presents an ontology centric architecture for mediating interactions is presented in a semantic web based e-commerce environment. The Design Science approach is applied for this purpose. The potential of the framework is illustrated as a functional model by using it to model the hierarchy of tasks in a consumer decision-making process as it applies in an e-commerce setting. Ontologies are used to express the perceptual operations on the external task environment, the intuitive operations on the internal task representation, and the constraint satisfaction and situated actions conforming to reasoning from the cognitive fit. It is maintained that actions themselves cannot be enforced, but when the meaning from mental imagery and the task environment are brought into coordination, it leads to situated actions that change the present situation into one closer to what is desired. To test the usability of the ontologies we use the Web Ontology Language (OWL) to express the semantics of the three representations. We also use OWL to validate the knowledge representations and to make rule-based logical inferences on the ontological semantics. An e-commerce application was also developed to show how effective guidance can be provided by constructing semantically rich target pages from the knowledge manifested in the ontologies.
77

Studie populace kalouse ušatého (Asio otus) na zimovišti v Kladně / Monitoring of the Long-eared Owl (Asio otus) Population at the Town of Kladno Wintering Place

Ponikelská, Eliška January 2015 (has links)
My thesis deals with the study of the population of the Long-eared Owl (Asio otus) on a wintering place in Kladno - Kročehlavy. I mention numbers, arrivals and departures of the Long-eared Owl during the years 2013-2015 and the influence of abiotic factors on these results. I also deal with ringing and recoveries of these owls in the territory of Kladno. I verify the hypothesis of the influence of warm weather, rainfall and snow cover on the representation of small mammals and birds species in the diet of the Long-eared Owl in this thesis. In addition, my thesis is devoted to the analysis of methodology and species identification in food of the Long-eared Owl by skulls and pelvic bones. In my thesis, when determining the type of small mammals I deal with sexing of Common Vole (Microtus arvalis) and Wood Mouse (Apodemus sylvaticus) of the pelvic bones. According to bone fragments of the pelvis dominant representation of male Common Voles and Wood Mouse in a certain period of winter was investigated. On the basis of the obtained results I have compiled charts and tables and I have compared them with previous research from the years 2006 - 2012 in the same study area in Kladno - Kročehlavy. Keywords: Long-eared Owl (Asio otus), diet, weather, Common Vole (Microtus arvalis), Wood Mouse (Apodemus...
78

[en] BENCH: A TOOL TO GENERATE BENCHMARK DATA TO TEST CONCEPTUAL SCHEMA ALIGNMENT ALGORITHMS / [pt] BENCH: UM GERADOR DE DADOS PARA TESTAR ALGORITMOS DE ALINHAMENTO DE ESQUEMAS CONCEITUAIS

GUYLERME VELASCO DE SOUZA FIGUEIREDO 24 September 2013 (has links)
[pt] Esta dissertação descreve uma ferramenta para teste e avaliação de algoritmos de alinhamento de esquemas a partir da criação de um conjunto de esquemas conceituais, populados com dados. A ferramenta, simplesmente chamada de Bench, possibilita a importação de qualquer conjunto de dados com um esquema conceitual bem definido e oferece facilidades para gerar variações deste esquema através de transformações que refletem alternativas de projeto comumente encontradas. Estas transformações de fato definem alinhamentos de referência entre o esquema original e suas variantes. O Bench permite ainda calcular o desempenho de um algoritmo de alinhamento de esquemas submetido para testes, comparando os alinhamentos de referência com os alinhamentos encontrados pelo algoritmo em teste. / [en] This dissertation describes a tool for generate benchmark data to test schema matching algorithms based on the creation of a set of conceptual schemas, populated with data. The tool, simply called Bench, allows importing any data set with a well-defined conceptual schema and offers facilities to generate variations of the schema through transformations that reflect structural alternatives found in typical conceptual modeling. Such transformations in fact define reference alignments between the original schema and its variations. Bench also permits evaluating the performance of the schema matching algorithm submitted for testing by comparing the reference alignments with those the algorithm under testing is able to find.
79

Utilização de ontologias para certificação de boas práticas em modelagem de processos de negócio / Using ontologies for the certification of best practices in business process modeling

Goldberg Júnior, Valter Helmuth January 2016 (has links)
A gestão por processos de negócio aumenta a qualidade de produtos e serviços e diminui o custo operacional nas organizações. Para realizar gestão por processos é necessário mapear estes processos em modelos de processo de negócio que precisam ter qualidade sintática, semântica e pragmática. A qualidade pragmática, em particular, garante que um modelo é compreensível. Os modelos são criados por analistas de processo, os quais reúnem informações que estão distribuídas pela organização e, a partir do conhecimento dos stakeholders do processo. Esta é uma tarefa complexa, que nem sempre resulta em modelos de processo com boa qualidade pragmática. Processos com baixa qualidade pragmática podem ser de difícil entendimento pelos stakeholders do processo. Para certificar a qualidade pragmática é necessário testar o entendimento do processo com novos usuários. Na maioria das vezes é difícil obter novos usuários para realizar testes. Este trabalho propõe uma abordagem que tem como base uma ontologia para representar modelos de processo e boas práticas de modelagem para auxiliar na identificação de modelos com baixa qualidade pragmática. A abordagem desenvolvida inclui o desenvolvimento de um plug-in para o editor de ontologia Protégé, que a partir de indicadores propostos na literatura automatiza a identificação de problemas na qualidade pragmática da modelagem de processos de negócio. Esta ferramenta pode ser utilizada no contexto acadêmico em cursos de modelagem de processos de negócio, auxiliando alunos no entendimento de boas práticas de modelagem, e no contexto empresarial, para revisar grandes repositórios de processos e selecionar os modelos que possam ter problemas na qualidade pragmática. / Business Process Management (BPM) increases the products and services quality and decreases operational costs in organizations. BPM requires the mapping of such process models that must present synthetic quality, semantic quality and pragmatic quality. Pragmatic quality, in particular, ensures understandability of the model. Models are designed by process analysts, gathering information spread at the organization and the knowledge of stakeholders. The design task is complex and some times does not result in process models with high pragmatic quality. Process model with low pragmatic quality may be difficult to understand by process stakeholders. Pragmatics quality certication tests the understanding of the process with new users. Most of the time it is hard to get new users to run tests. This work proposes an approach based on an ontology to represent process models and modeling practices to identify models with low pragmatic quality. The proposed approach is based on the development of a plug-in for Protégé ontology editor, and uses metrics from the literature to identify pragmatic quality problems in process models. This tool can be aplied in academic context so that students can better understant best practices in business process modeling, and also at business context, to review large process repositories selecting models which may have pragmatic quality problems.
80

Intégration de l'Internet 3G au sein d'une plate-forme active

Chamoun, Maroun 05 1900 (has links) (PDF)
Les réseaux à base de politiques (PBN) définissent un paradigme des plus prometteurs pour la gestion et le contrôle des ressources réseaux. COPS tend à être le protocole de facto pour l'utilisation de ce type d'applications. La question se pose de savoir comment déployer ce type de services pour permettre les échanges entre les différentes entités protocolaires du réseau (PEP et PDP). C'est à ce niveau que nous proposons de faire intervenir la notion de réseaux actifs, vu que ce paradigme permet d'intégrer du code exécutable aux paquets transférés et/ou nœuds en vue de distribuer et de configurer dynamiquement les services du réseau. D'autre part, une grande effervescence existe actuellement autour du déploiement des Web services sur Internet à l'aide du protocole SOAP. Toujours dans le cadre de l'Internet mais selon une perspective différente, la représentation sémantique des données, et grâce à la définition d'ontologies, permet aux logiciels d'interpréter intelligemment les données qu'elles gèrent et de ne plus jouer le rôle de simple équipement de stockage passif. La synergie entre les 4 paradigmes: PBN, Réseaux actifs, Web services, et représentation sémantique des données, présente une solution intégrée et portable des plus intéressantes pour la représentation des nœuds de l'architecture active, la conception, l'implémentation et le déploiement de services, et plus spécifiquement un service de gestion dynamique contrôlable et intelligent, dont les données (politiques et règles) sont représentés par une même ontologie.

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