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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.
21

Climate change adaptation and sustainable forest management in the boreal forest

Ogden, Aynslie Erna Elizabeth 05 1900 (has links)
Climate change will pose increasing challenges to forest managers working to achieve sustainable forest management in the boreal forest. A logical starting point for climate change adaptation is to proactively identify management practices and policies that have a higher likelihood of achieving management objectives across a wide range of potential climate futures. This research implemented an approach to identifying such measures by tapping into the experiential knowledge base of local forest practitioners. The assessment was organized according to a structured decision-making (SDM) approach. Northern forest practitioners consider the goals of climate change adaptation to be synonymous with those of sustainable forest management indicating that the criteria for the conservation and sustainable management of boreal forests as defined by the Montréal Process are suitable objectives against which the performance of alternative adaptation options can be assessed. The case study area for this research was the Champagne and Aishihik Traditional Territory of southwest Yukon where a climatically-driven, large-scale spruce bark beetle disturbance has been driving forest management planning yet climate change considerations have not been directly addressed in the planning process. Twenty-four adaptation options were identified as being important to implement in forest development areas to achieve regional goals and objectives of forest management across three scenarios of climate change. In addition, the performance of alternative strategies to re-establish forests was assessed. Results indicate that the applicability of alternative forest renewal adaptation strategies is strongly related to the objectives of forest management which differed across the forest management planning area. However, since none of the strategies were judged to perform highly across any of the scenarios of climate change, additional work is needed to explore whether a threshold of acceptability can be met even with the adoption of adjustments to forest management policies and practices. If not, management objectives themselves may need to be revised. An extensive list of research and monitoring needs were also identified, an indication that climate change is providing the imperative for a more comprehensive research and monitoring program to support the sustainable management of forest resources in this region. The next steps in a SDM approach are to implement adaptation options and strategies deemed appropriate and to monitor their performance in achieving management objectives within an adaptive management context.
22

Climate change adaptation and sustainable forest management in the boreal forest

Ogden, Aynslie Erna Elizabeth 05 1900 (has links)
Climate change will pose increasing challenges to forest managers working to achieve sustainable forest management in the boreal forest. A logical starting point for climate change adaptation is to proactively identify management practices and policies that have a higher likelihood of achieving management objectives across a wide range of potential climate futures. This research implemented an approach to identifying such measures by tapping into the experiential knowledge base of local forest practitioners. The assessment was organized according to a structured decision-making (SDM) approach. Northern forest practitioners consider the goals of climate change adaptation to be synonymous with those of sustainable forest management indicating that the criteria for the conservation and sustainable management of boreal forests as defined by the Montréal Process are suitable objectives against which the performance of alternative adaptation options can be assessed. The case study area for this research was the Champagne and Aishihik Traditional Territory of southwest Yukon where a climatically-driven, large-scale spruce bark beetle disturbance has been driving forest management planning yet climate change considerations have not been directly addressed in the planning process. Twenty-four adaptation options were identified as being important to implement in forest development areas to achieve regional goals and objectives of forest management across three scenarios of climate change. In addition, the performance of alternative strategies to re-establish forests was assessed. Results indicate that the applicability of alternative forest renewal adaptation strategies is strongly related to the objectives of forest management which differed across the forest management planning area. However, since none of the strategies were judged to perform highly across any of the scenarios of climate change, additional work is needed to explore whether a threshold of acceptability can be met even with the adoption of adjustments to forest management policies and practices. If not, management objectives themselves may need to be revised. An extensive list of research and monitoring needs were also identified, an indication that climate change is providing the imperative for a more comprehensive research and monitoring program to support the sustainable management of forest resources in this region. The next steps in a SDM approach are to implement adaptation options and strategies deemed appropriate and to monitor their performance in achieving management objectives within an adaptive management context. / Forestry, Faculty of / Graduate
23

Rychlá detekce aplikačních protokolů / Fast Detection of Application Protocols

Grochol, David January 2014 (has links)
Master thesis is focused on classification of application protocols based on application data taken from layer L7 of ISO/OSI model. The aim of the thesis is to suggest a classifier for SDM system (Software defined monitoring) so it could be used for links with throughput up to 100 Gb/s. At the same time it should classify with the fewest possible errors.Designed classifier consists of two parts. First part depicts encoders for encoding selected attributes. Second part deals with evaluating circuit which detects series characteristic for particular application protocols on the output from the first part. Considered attributes and series are taken from statistic analyzes of application protocol data.The classifier itself is designed so it can be implemented in FPGA and enables modification set of application protocols who intended for classification. The quality of  designed classifier is tested on real network data. The results of classification are compared with current methods used for classification of application protocols.
24

Distributed radiofrequency signal processing based on space-division multiplexing fibers

García Cortijo, Sergi 13 July 2020 (has links)
[EN] Space-division multiplexing fibers emerged as a promising solution to overcome the imminent capacity crunch of conventional singlemode fiber networks. Despite these fibers were initially conceived as distribution media for long-haul high-capacity digital communications, they can be applied to a wide variety of scenarios including centralized radio access networks for wireless communications, data-center interconnects, Microwave Photonics signal processing and fiber sensing. Particular interest is raised by emerging communications paradigms, such as 5G and The Internet of Things, which require a full integration between the optical fiber and the wireless networks segments. Microwave Photonics, discipline that focuses on the generation, processing, control and distribution of radiofrequency signals by photonics means, is called to play a decisive role. One of the major challenges that Microwave Photonics has to overcome to satisfy next-generation communication demands relates to the reduction of size, weight and power consumption while assuring broadband seamless reconfigurability and stability. There is one revolutionary approach that has however been left untapped in finding innovative ways to address that challenge: exploiting space, the last available degree of freedom for optical multiplexing. In this Thesis, we propose to exploit the inherent parallelism of multicore and few-mode fibers to implement sampled discrete true time delay lines, providing, in a single optical fiber, a compact and efficient approach for both Microwave Photonics signal distribution and processing. For the multicore fiber approach, we study the influence of the refractive index profile of each heterogeneous core on the propagation characteristics as to feature specific group delay and chromatic dispersion values. We designed and fabricated two different heterogeneous trench-assisted 7-core fibers that behave as sampled true time delay lines. While one of them was fabricated by using 7 different preforms to feature a plenary performance, the other one employed a single preform with the aim of minimizing fabrication costs. In the case of few-mode fibers, we propose the implementation of a tunable true time delay line by means of a custom-designed fiber with a set of inscribed long period gratings that act as mode converters to properly tailor the sample group delays. We designed and fabricated a true time delay line on a 4-mode fiber by inscribing 3 long period gratings at specific positions along the fiber link. As a proof-of-concept validation, we experimentally demonstrated different Microwave Photonics signal processing functionalities implemented over both multicore and few-mode fiber approaches. This work opens the way towards the development of distributed signal processing for microwave and millimeter wave signals in a single optical fiber. These true time delay lines can be applied to a wide range of Information and Communication Technology paradigms besides fiber-wireless communications such as broadband satellite communications, distributed sensing, medical imaging, optical coherence tomography and quantum communications. / [ES] La multiplexación por división espacial en fibras ópticas surgió como una solución prometedora al inminente colapso en la capacidad de las redes de fibra monomodo convencionales. Aunque estas fibras fueron concebidas inicialmente como medio de distribución en comunicaciones digitales de larga distancia y alta capacidad, pueden emplearse en una amplia variedad de escenarios, incluyendo redes de acceso radio centralizadas para comunicaciones inalámbricas, interconexiones en centros de datos, así como procesado de señal en Fotónica de Microondas y sensado en fibra. Los paradigmas de comunicaciones emergentes despiertan un interés particular, como 5G y el Internet de las Cosas, que requieren una integración total entre el segmento de red de fibra óptica y el inalámbrico. La Fotónica de Microondas, disciplina que se focaliza en la generación, procesado, control y distribución de señales de radiofrecuencia por medio de la fotónica, está destinada a jugar un papel decisivo. Uno de los mayores desafíos que la Fotónica de Microondas debe superar para satisfacer los requisitos de las nuevas generaciones de comunicaciones se basa en la reducción de tamaño, peso y consumo de potencia, mientras se garantiza reconfiguración y estabilidad de banda ancha. Encontramos aquí un enfoque revolucionario capaz de abordar este desafío de una manera innovadora que, sin embargo, no ha sido aprovechado en este contexto: la explotación del espacio, el último grado de libertad para multiplexación óptica. En esta Tesis, proponemos explotar el paralelismo inherente de las fibras ópticas multinúcleo y de pocos modos para implementar líneas de retardo en tiempo real muestreadas que proporcionan, en una sola fibra óptica, una solución compacta y eficiente tanto para distribución como para procesado de señales de Fotónica de Microondas. En el caso de fibras multinúcleo, estudiamos la influencia del perfil de índice de refracción de cada núcleo heterogéneo en las características de propagación para que exhiba unos valores concretos de retardo de grupo y dispersión cromática. Diseñamos y fabricamos dos fibras distintas de 7 núcleos con zanjas que se comportan como líneas de retardo en tiempo real muestreadas. Mientras que una de ellas se fabricó utilizando 7 preformas diferentes para garantizar un funcionamiento completo, la segunda se fabricó utilizando una única preforma con el objetivo de minimizar costes de fabricación. En el caso de fibras de pocos modos, proponemos la implementación de líneas de retardo en tiempo real sintonizables mediante el uso de una fibra específicamente diseñada y la inscripción de un conjunto de redes de difracción de periodo largo que actúan como conversores de modos para ajustar adecuadamente el retardo de grupo de las muestras. Diseñamos y fabricamos una línea de retardo en tiempo real en una fibra de 4 modos mediante la inscripción de 3 redes de difracción de periodo largo en posiciones concretas a lo largo de enlace de fibra. Como validación de prueba de concepto, demostramos experimentalmente diferentes funcionalidades de procesado de señal de Fotónica de Microondas implementadas en fibras multinúcleo y de pocos modos. Este trabajo abre el camino hacia el desarrollo del procesado de señal distribuido para señales de microondas y ondas milimétricas en una única fibra óptica. Además, las líneas de retardo en tiempo real desarrolladas pueden aplicarse a una amplia variedad de paradigmas de Tecnologías de la Información y Comunicaciones más allá de las comunicaciones radio sobre fibra, como es el caso de las comunicaciones de banda ancha por satélite, el sensado distribuido, la imagen médica, la tomografía óptica coherente y las comunicaciones cuánticas. / [CA] La multiplexació per divisió espacial en fibres òptiques va sorgir com una solució prometedora a l'imminent col·lapse en la capacitat de les xarxes de fibra monomode convencionals. Encara que estes fibres foren concebudes inicialment com a mitjà de distribució en comunicacions digitals de llarga distància i alta capacitat, poden emprar-se en una àmplia varietat d'escenaris, incloent xarxes d'accés radio centralitzades per a comunicacions sense fils, interconnexions en centres de dades, així com processat de senyal en Fotònica de Microones i sensat en fibra. Els paradigmes de comunicacions emergents desperten un interès particular, com el 5G i la Internet de les Coses, que requereixen una integració total entre els segments de xarxa de fibra òptica i el de sense fils. La Fotònica de Microones, disciplina que es focalitza en la generació, processat, control i distribució de senyals de radiofreqüència per mitjà de la fotònica, està destinada a jugar un paper decisiu. Un dels majors desafiaments que la Fotònica de Microones ha de superar per satisfer els requisits de les noves generacions de comunicacions es basa en la reducció de grandària, pes i consum de potència, mentre es garanteix reconfiguració i estabilitat de banda ampla Trobem ací un enfocament revolucionari capaç d'abordar aquest desafiament d'una manera innovadora que, no obstant això, no ha sigut aprofitat encara en este context: la explotació de l'espai, l'últim grau de llibertat per a multiplexat òptic. En aquesta Tesi, proposem explotar el paral·lelisme inherent de les fibres òptiques multinucli i de pocs modes per a implementar línies de retard en temps real de mostres discretes que proporcionen, en una sola fibra òptica, una solució compacta i eficient tant per a distribució com per a processat de senyals de Fotònica de Microones. En el cas de fibres multinucli, estudiem la influència del perfil d'índex de refracció de cada nucli heterogeni en les característiques de propagació perquè exhibisca uns valors concrets de retard de grup i dispersió cromàtica. Dissenyem i fabriquem dues fibres distintes de 7 nuclis amb rases que es comporten com a línies de retard en temps real mostrejades. Mentre que una d'elles es va fabricar utilitzant 7 preformes diferents per a garantir un funcionament complet, la segona va fabricar-se utilitzant una única preforma amb l'objectiu de minimitzar costos de fabricació. En el cas de fibres de pocs modes, proposem la implementació de línies de retard en temps real sintonitzables mitjançant l'ús d'una fibra específicament dissenyada i la inscripció d'un conjunt de xarxes de difracció de període llarg que actuen com a convertidors de modes per tal d'ajustar adequadament el retard de grup de les mostres. Dissenyem i fabriquem una línia de retard en temps real en una fibra de 4 modes mitjançant la inscripció de 3 xarxes de difracció de període llarg en posicions concretes al llarg de l'enllaç de fibra. Com a validació de proba de concepte, demostrem experimentalment diferents funcionalitats de processat de senyal de Fotònica de Microones implementades en fibres multinucli i de pocs modes. Aquest treball obri el camí cap al desenvolupament del processat de senyal distribuït per a senyals de microones i ones mil·limètriques en una única fibra òptica. A més, aquestes línies de retard en temps real poden aplicar-se a una àmplia varietat de paradigmes de Tecnologies de la Informació i Comunicacions més enllà de les comunicacions radio sobre fibra, com es el cas de les comunicacions de banda ampla per satèl·lit, el sensat distribuït, la imatge mèdica, la tomografia òptica coherent i les comunicacions quàntiques. / Agradezco al Ministerio de Economía y Competitividad del Gobierno de España por la financiación recibida mediante la ayuda FPI. / García Cortijo, S. (2020). Distributed radiofrequency signal processing based on space-division multiplexing fibers [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/147858 / TESIS
25

Decision support framework for the adoption of software development methodologies.

Simelane, Lynette January 2019 (has links)
M. Tech. (Department of Information and Communication Technology, Faculty of Applied and Computer Sciences), Vaal University of Technology. / There are many software development methodologies that are used to control the process of developing a software system. However, no exact system has been found which could help software engineers in selecting the best software development methodology (SDM). The increasing complexity of software development today has led to complex management of software systems. This complexity increases the challenges faced by professionals in selecting the most appropriate SDM to adopt in a project. This is important because the wrong choice of methodology is costly for the organization as it may impact on deliveries, maintenance costs, budget projects and reliability. In this study we propose a decision support framework to assist professionals in the selection of appropriate software development methodologies that would fit each organisation and project setting. The case based reasoning (CBR) methodology was implemented in this study. This methodology focuses on problem solving that centres on the reutilization of past experiences. The CBR methodology was implemented using the SQL programming language. We tested the precision of the decision support framework by comparing the recommended methodology to the actual software methodology that was adopted for the project. The DS framework recorded an 80% precision result. In addition, the findings contribute to reducing the software crisis faced by today’s professionals. Therefore the framework can be adopted as a reliable tool for methodology selection in software development projects.
26

Factors that Cause Repeated Referral to the Disciplinary Alternative Education Program

Avery, Koury A. 01 January 2016 (has links)
Students are referred to alternative schools such as the Disciplinary Alternative Education Program (DAEP) for violations against the student code of conduct. Students who are referred and attend DAEPs are more likely to make failing grades and drop out of school permanently. However, a lack of understanding existed about why some students repeatedly receive referrals to the DAEP.The purpose of this case study was to gain an understanding about why some students are repeatedly being sent to the DAEP in a school district in north central Texas. The conceptual framework was based on Catalano and Hawkins' social development theory which posited that through consistent socialization, children learn prosocial or antisocial behavior patterns from the social units to which they are bonded. In this study, 14 purposefully selected classroom teachers participated in one-on-one conversational interviews to explore teachers' perceptions about why some students are repeatedly sent to the DAEP. Inductive analysis was used for coding and identifying emerging concepts, themes, and events. Six major themes emerged from analysis of the data: school structure, classroom/behavior management, class size, student labeling, extracurricular activities, and teacher-student relationships. The results illustrate the need for changes to disciplinary policies, new transition procedures, and improved staff training. This study may contribute to positive social change by suggesting strategies that schools could use to decrease the number of referrals to the DAEP. In turn, by decreasing the number of referrals school failure and dropout rates would decrease and as a result enable youth to eventually become productive members of society.
27

Architecture structurale de la ceinture de Gaspé (Canada) : Imagerie sismique intégrée et application à l'évaluation pétrolière

Bêche, Martin 08 December 2008 (has links) (PDF)
La péninsule de la Gaspésie (Québec, Canada) présente un potentiel pétrolier dans les roches datées de l'Ordovicien tardif au Dévonien inférieur. Dans l'est de la ceinture de Gaspé, des puits producteurs de gaz prouvent la présence de réservoirs pétroliers. Des nouvelles études structurales et des études de bassin dans la ceinture de Gaspé permettent de mieux évaluer le potentiel pétrolier de cette région. Nous présentons ici une nouvelle méthodologie pour la prospection d'hydrocarbures dans les régions de piémont de type « fold and thrust belt » comme la ceinture de Gaspé. Nous avons développé cette méthodologie en la testant au niveau de la partie centrale de la ceinture de Gaspé. Nous avons intégré les données géologiques et géophysiques disponibles pour l'étape d'imagerie sismique 2D afin de construire une image sismique directement en profondeur, ce qui a permis d'améliorer l'interprétation structurale, notamment la caractérisation des structures profondes et des failles majeures. Ce travail est suivi d'une modélisation de bassin afin d'évaluer le potentiel pétrolier. Cette étude s'effectue en plusieurs étapes : 1) La construction du modèle structural : L'intégration des données géologiques dans l'étape de la migration en profondeur avant sommation permet d'améliorer le rendu des images sismiques. Ces nouvelles images sont plus fiables et, étant migrées directement en profondeur, rendent les interprétations plus proches de la géometrie réelle du sous-sol. Ces informations permettent de construire un modèle géologique plus complexe et de mieux contraindre le modèle structural de la ceinture acadienne. Les nouvelles interprétations ont permis en particulier, de mieux comprendre la relation entre les ceintures acadienne et taconienne. 2) L'évolution du modèle structural : il a été possible de valider la cohérence de la géométrie structurale grâce aux techniques de restauration. Cependant ce procédé n'a été appliqué qu'au niveau du Synclinal du Lac des Huit-Miles sur les successions stratigraphiques siluro-dévoniennes de la ceinture acadienne : les formations cambroordoviciennes ont été déformées par les orogenèses taconiennes et acadiennes ce qui rend impossible leur restauration. Ce scénario cinématique a été utilisé pour comprendre l'évolution géodynamique de la ceinture de Gaspé et ainsi permettre de proposer une nouvelle géométrie plus favorable à la production et à la migration des hydrocarbures. 3) Évaluation du système pétrolier : Suite à l'étape de restauration, la modélisation de bassin avec le logiciel Temis2D® a été appliquée à la succession stratigraphique Silurien-Dévonien du synclinal du Lac des Huit-Milles et à l'anticlinal de Causapscal. Temis2D® a permis de prédire l'évolution de la roche mère et le degré de maturation ainsi que la génération et l'expulsion des hydrocarbures, en utilisant le modèle structural et les données géochimiques des puits de la ceinture de Gaspé.
28

A Fuzzy Based Decision Support System For Locational Suitability Of Settlements / Odunpazari, Eskisehir Case Study

Ercan, Ismail 01 February 2006 (has links) (PDF)
Spatial Decision Making as a branch of decision making science deals with geographically related data in order to achieve complex spatial decision problems. Fuzzy set theory is one of the methods that can be used to come up with these types of problems. On the other hand, Geographical Information Systems (GIS) is one of the most powerful tools that we can use to accomplish spatial decision problems. Selection of the suitable site or land-use for the real estate is also a spatial decision making problem. When we consider the initial dynamics of the suitably located property from the point of view of value and potential we observe that the &ldquo / good location&rdquo / is the dominating factor. This study reports on the development of a kind of decision support system for locational suitability of settlements that integrates the fuzzy set (FZ) theory, a rule-based system (RBS) and GIS. This study is thought as the assistant for the property managers that are buyers and sellers. It can function as the property consultant for the buyers when they are looking for a property to buy and also it helps the real estate agencies to sell their properties. On the other hand, different scenarios of the potential areas according to the different user&rsquo / s preferences are depicted and they are joined and compared with the results of the vulnerability to earthquake hazards&rsquo / of the same area. Odunpazari - Eskisehir area is selected for implementation of the case study because of the data availability. As a result of this study, it can be said that most suitable property changes depending on the people&rsquo / s preferences. In addition, it is seen that most of the buildings that are locationally suitable are highly vulnerable to the earthquake hazards.
29

Project Management Methodologies for Software Development in Startups

Zavazava, Tinashe January 2022 (has links)
Startups indeed play a pivotal role in society as agents of innovation and generators of employment. Despite this, a large proportion of startups fail. As a substantial amount of these temporary project-like companies called startups engage in software development and as application of project management has been correlated with project success, this research exploits a gap in the literature concerned with best practices as it pertains to project management methodologies for software development in startups. Given that a significant number of academic studies have already been conducted in the area of software development practices in startups spanning project management methodologies and software development methodologies, this research applies a strategy of systematic review as along with the application of thematic synthesis is appropriate for ascertaining the current state of knowledge and the search for some consensus. Consequently, this has been deemed to be an appropriate strategy for answering the research question: What are the best practices in applying Project Management Methodologies for software development projects in startups? The scope of the systematic review is the last decade (from 2012 to 2022) and the PRISMA framework has been used to facilitate the identification and screening of records. As a result, 17 studies with varying methods were deemed eligible and of high quality according to the quality assessment guidelines by Garousi et al. The main findings of this study identify three high-order themes for best practices in applying project management methodologies for software development in startups: Agility & Maturity, Empower & Value People, Tool Usage & Support.
30

SPECIES DISTRIBUTION MODELING OF AMERICAN BEECH (FAGUS GRANDIFOLIA EHRH.) DISTRIBUTION IN SOUTHWESTERN OHIO

Flessner, Brandon P. 05 May 2014 (has links)
No description available.

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