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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.
61

Integração das estratégias de sustentabilidade: \"top-down\" e \"bottomup\" como ferramentas de aprendizagem para a alfabetização ecológica no Ensino Médio / Integration of sustainability strategies: \"top-down\" and \"bottom-up\" as learning tools for ecological literacy in high school

Tainá Gouvêa Galvão Silva 03 August 2018 (has links)
O desenvolvimento sustentável no final do século XX surgiu para expressar preocupações com graves problemas que causam riscos a vida no planeta. O uso do planeta de forma sustentável exigirá diferentes estratégias de sustentabilidade. Neste sentido têm-se as estratégias que abordam o nível mais elevado do ecossistema referidas como Top-down e as estratégias que abordam componentes locais ou regionais referidas como bottom-up. A escola traz essa compreensão nos conceitos e fenômenos ecológicos. No entanto, a compreensão dessas abordagens com apoio interdisciplinar faz com que o aluno entenda os fenômenos ecológicos de forma mais crítica. Assim, para um aprendizado motivador, o professor pode utilizar como recurso didático além dos espaços formais de educação também espaços não formais de educação, ou seja, aulas de campo em ambientes naturais. Com o intuito de promover no ensino de ecologia a alfabetização ecológica dos alunos no Ensino Médio, este trabalho elaborou uma proposta didática com apoio interdisciplinar (Biologia, Língua Portuguesa e Geografia) e com ênfase nas estratégias Top-down e bottom-up abordadas tanto em espaços formais quanto não formais de educação. O método de ensino em espaço formal de educação apesar de estar estruturado didaticamente para abranger a ecologia não se apresentou motivadora ao aluno e muitos dos conceitos e fenômenos ecológicos não foram assimilados por eles. Em contrapartida, a integração interdisciplinar em associação com as estratégias de Top-down e bottom-up em espaços não formais de educação foi motivadora para o aluno melhorando o seu desempenho com relação à assimilação dos conceitos e fenômenos biológicos promovendo a alfabetização ecológica dos alunos. Espera-se com esse trabalho ter contribuído para o ensino e aprendizagem do tema sustentabilidade através da promoção da alfabetização ecológica dos alunos de Biologia no Ensino Médio em escolas públicas com a formação de cidadãos mais conscientes e críticos em assuntos ambientais. / Sustainable development in the late 20th century has emerged to express concerns about serious life-threatening problems on the planet. The use of the planet in a sustainable way will require different sustainability strategies. In this sense we have the strategies that approach the highest level of the ecosystem referred to as \"top-down\" and the strategies that approach local or regional components referred to as \"bottom-up\". The school brings this understanding into concepts and ecological phenomena. However, understanding these approaches with interdisciplinary support makes the student understand ecological phenomena more critically. Thus, for a motivating learning, the teacher can use as a didactic resource beyond the formal spaces of education also non-formal spaces of education, that is, field lessons in natural environments. In order to promote ecological literacy among students in high school, this work elaborated a didactic proposal with interdisciplinary support (Biology, Portuguese Language and Geography) and with emphasis on top-down and bottom-up strategies addressed in both formal and non-formal education settings. The method of teaching in formal educational space despite being structured to cover ecology did not present itself as motivating to the student and many concepts and ecological phenomena were not assimilated by them. In contrast, interdisciplinary integration in association with top-down and bottom-up strategies in non-formal education spaces was motivating for the student to improve his performance in relation to the assimilation of concepts and biological phenomena by promoting literacy of the students. It is hoped that this work contributed to the teaching and learning of the sustainability theme through the promotion of the ecological literacy of Biology students in High School in public schools with the formation of citizens more conscious and critical in environmental issues.
62

Tamanhos pictóricos percebidos sobre gradientes de textura desenhados e fotografados após exposições breves / Pictorial size perceived under line-drawing and photographed texture gradient after brief exposures

Leonardo Gomes Bernardino 11 September 2012 (has links)
O presente estudo teve por objetivo investigar a dinâmica temporal da percepção de tamanho de objetos inseridos em gradientes de textura, provenientes de desenho gerado computacionalmente (gradiente de perspectiva) e de fotografia com elementos naturais (gradiente fotografado). Além disso, verificou-se a ocorrência e padrão dos movimentos oculares nestas condições. Para isso, foram realizados 2 experimentos. No primeiro experimento, dois círculos negros eram apresentados no meridiano vertical e a tarefa dos 96 participantes foi indicar em qual parte do campo visual, superior ou inferior, foi apresentado o maior círculo. Usando o método das escadas duplas, estes círculos eram apresentados brevemente (50, 100, 150 ou 200 ms) em três condições de fundos de tela (sem textura, gradiente de perspectiva ou gradiente fotografado). Foram calculados a inclinação da função psicométrica e o ponto de igualdade subjetivo (PIS) como medidas da sensibilidade discriminativa e da distorção perceptiva, respectivamente. Os resultados mostraram que os participantes discriminaram melhor o tamanho dos estímulos à medida que o tempo de exposição aumentava, independentemente do gradiente de textura. A análise do PIS revelou que há uma forte distorção do tamanho aos 100 ms para o gradiente de perspectiva e aos 150 ms para o gradiente fotografado. No segundo experimento, 24 participantes realizaram uma tarefa semelhante ao do primeiro experimento e utilizou-se um eye tracker para registrar o movimento ocular. Os resultados mostraram que, em apresentações de 150 e 200 ms, os movimentos oculares ocorreram em menos de 10% das tentativas em todos os fundos de tela. Isto indica que a redução das distorções de tamanho após os 100 ms observada no primeiro experimento não é explicada completamente pela alocação da atenção. Tomados em conjunto, estes resultados sugerem que o processamento e integração das informações de tamanho e profundidade são mediados principalmente por mecanismos bottom-up. Ademais, em uma condição de menor restrição temporal (1500 ms), a presença de informações de profundidade afetou a dimensão espacial das fixações e sacadas, mas não a dimensão temporal. Os participantes olharam preferencialmente para o estímulo apresentado no campo visual superior, o que indica que a atenção foi alocada às posições de maior profundidade. Os resultados também indicaram que os estímulos maiores capturaram tanto a atenção transitória quanto a atenção sustentada. Assim, este estudo permitiu um maior conhecimento sobre os mecanismos perceptivos e atentivos envolvidos no processamento das informações de tamanho e de profundidade. / This study aimed to investigate the temporal dynamics of object size perception under texture gradients from line-drawing (perspective gradient) and photograph with natural elements (photographed gradient). Additionally, it was analyzed the occurrence and the pattern of eye movements in these conditions. For this, we carried out 2 experiments. In the first experiment, two black circles were displayed in the vertical meridian and 96 participants reported whether the bigger one was presented at the lower or upper visual field. By using double staircase psychophysics method, these circles were briefly presented (50, 100, 150 or 200 ms) in three background conditions (no texture, perspective gradient or photographed gradient). The slope of the psychometric function and the points of subjectivity equality (PSE) were calculated and used as discrimination sensitivity and size distortion measures, respectively. The results showed a greater sensitivity to size discrimination as exposure time increased, regardless the texture gradient. The analysis of PSE indicated greater size distortions in perspective gradient at 100 ms and in photographed gradient at 150 ms. In the second experiment, 24 participants performed a task similar to that in Experiment 1 while an eye tracker recorded their eye-movements. The results showed that, at 150 and 200 ms, eye movements occurred in less than 10% of trials in all backgrounds. It indicates that the size distortion reduction after 100 ms observed in the first experiment cannot be fully explained by attention allocation. Taken together, these results suggest that the process and integration of size and depth information are mainly mediated by bottom-up mechanism. Moreover, in a less time constrain condition (1500 ms), depth cues affected the spatial measures of fixations and saccades, but not the temporal ones. The participants looked more frequently at the stimulus on the upper visual field, indicating that attention has been allocated to positions of greater depth. The results also indicated that large stimulus capture both transient and sustained attention. Thus, this study provides a better understanding of perceptual and attentive mechanisms involved in size and depth process.
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Coupling Laser with Mass Spectrometry for Biomolecules Characterization : From Peptides towards Protein Fibrils / Couplage entre spectrométrie de masse et spectroscopie laser pour la caractérisation de biomolécules : des petits peptides modèles à de très gros assemblages protéiques

Halim, Mohammad Abdul 14 June 2017 (has links)
La spectrométrie de masse est devenue un outil indispensable pour la recherche en protéomique, notamment grâce au développement récent de nouveaux spectromètres de masse comme l’Orbitrap et de nouvelles méthodes de dissociation. La stratégie « bottom-up » (analyse des mélanges de peptides protéolytiques) est la plus utilisée par son efficacement et sa simplicité par rapport à la stratégie top-down (analyse des peptides plus longs ou des protéines intactes), mais cette dernière permet une caractérisation plus complète des isoformes de protéines et des modifications post-traductionnelles.Les méthodes de dissociation utilisant des photons, comme la photodissociation dans le domaine ultra-violet (UVPD) et la dissociation multiphotonique infrarouge (IRMPD), ont reçu une grande attention comme approches alternatives aux méthodes de dissociation par collision. L'absorption du photon UV à haute énergie peut être « diluée » sur l'ensemble du peptide ou de la protéine et provoque une fragmentation étendue du squelette peptidique (liaisons C-C), tandis que les photons IR à faible énergie augmentent progressivement l'énergie interne et dissocient préférentiellement les liaisons amide (C-N) les plus labiles.Cette thèse est centrée sur le développement de méthodes et les applications pour une caractérisation structurale de biomolécules par des méthodes d'activation utilisant des photons. L'intérêt de combiner des photons infrarouges à faible énergie et des photons UV à haute énergie dans un spectromètre de masse Orbitrap, pour la caractérisation de petites protéines, a été évalué. En outre, la dissociation infrarouge multiphotonique a été implémentée dans un piège à ions électrostatique afin d’étendre les méthodes de fragmentation aux macromolécules de très haut poids moléculaires dans le domaine mégadalton. L'une des principales avancées de cette thèse a été d'adapter ces méthodes de spectrométrie de masse aux objets biomoléculaires, allant des petits peptides (dans la gamme de masse de kilodalton) à des fibres de protéines entières (dans la gamme de masse de mégadalton) / The structural characterization of proteins often required them to be fragmented into small units containing only few amino acids. In bottom-up approach, proteins are cleaved into small peptides by enzyme then these peptides are subjected to further fragmentation in a collision cell of a tandem mass spectrometer. However, in top-down approach, proteins can directly be dissociated (without enzyme) into small fragments by collision, electron and photon-driven dissociations. Photon-based activation methods including ultraviolet photodissociation (UVPD) and infrared multiphoton dissociation (IRMPD) have received great attention as an alternative to electron-driven and collision induced dissociation methods. Absorption of the high-energy UV photon is dispersed over the whole peptide or protein and stimulates extensive C?Ca backbone fragmentation while the low-energy IR photons gradually increases the internal energy and thus favorably dissociates the most labile amide (C?N) bonds. This thesis focuses on the method development and applications for characterizing biomolecules by photon-based activation methods. The interest of combining high-energy UV photons and low-energy IR photons in an Orbitrap mass spectrometer, for protein and post-translationally modified peptide characterization, has been evaluated. Moreover, infrared multiphoton dissociation has been implemented in a gated electrostatic ion trap to push forward the limit of fragmentation methods to large megadalton ions. One of the main breakthroughs in this thesis is the ability to adapt these method developments and applications to biomolecular objects ranging from small peptides (in kilodalton mass range) to entire protein fibrils (in megadalton mass range)
64

Influence des propriétés de surface sur les performances de localisation d’icônes et de mots sur un écran : quelles recommandations pour un public âgé ? / Influence of perceptual features on the localization performances of icons and words on a screen : what recommendations for elderly ?

Moget, Caroline 14 December 2015 (has links)
Cette thèse en ergonomie s’inscrit dans le cadre d’un projet de conception industrielle d’un système innovant d’e-santé (HADAGIO), développé par l’entreprise SESIN et permettant le maintien à domicile de personnes âgées fragiles. Son objectif appliqué a été de produire des recommandations ergonomiques permettant d’améliorer les interfaces du système proposé sous la forme d’un portail d’applications web afin de les rendre faciles à utiliser par des personnes âgées et, ainsi, favoriser l’acceptation finale du dispositif HADAGIO. Ce travail s’est intéressé à la tâche de localisation d’informations sur un écran et, plus particulièrement, au rôle des éléments de surface (couleur et niveau de détails) des icônes et libellés lexicaux sur les performances de réalisation de cette tâche par des personnes âgées. Cette tâche est en effet particulièrement difficile pour ces dernières qui obtiennent des performances de localisation moindres que celles des jeunes (temps de réaction et nombre d’erreurs plus importants). Des recommandations graphiques pour la conception d’interfaces du portail HADAGIO ont émergées de ce travail, et permettent de faciliter la tâche de localisation des informations pour des personnes âgées. / This thesis in ergonomics is part of an industrial design project of an innovative e-health system (HADAGIO), developed by the company SESIN and allowing home support frail elderly. Its goal was applied to produce ergonomic recommendations for improving the interfaces of the system proposed in the form of a web portal software to make them easier to use and thus promote the final acceptance HADAGIO the device.This work has focused on the task of locating information on a screen and, in particular, the role of perceptual features (color and detail) lexical icons and labels on achieving performance of this task by elders. This task is indeed particularly difficult for this people who get lower localization performances than young people (reaction times and a larger number of errors). The models proposed for the target location task assumes that the knowledge possessed by individuals on the appearance of the target to locate allow improved performance. Given that advancing age does not affect the process involving knowledge stored in memory (Top Down type) implemented in this task it was to determine what could be the color of the role and Details of the target level in the implementation of these processes at a location task information.Graphics recommendations for HADAGIO portal interface design have emerged from this work, and provide information to facilitate the localization task for the elderly.
65

Localisation précise et fiable de véhicules par approche multisensorielle / Accurate and reliable vehicle localization thanks to a multisensor approach

Aynaud, Claude 08 December 2015 (has links)
La localisation d’un véhicule est une étape cruciale dans le développement des véhicules intelligents. Les recherches sur ce sujet ont connu un grand essor ces dernières années. L’accent est souvent porté sur la précision de la localisation, nous présentons ici une méthode de localisation sur carte existante dont l’objectif est d’estimer la position du robot non seulement de façon précise mais également de manière fiable. Pour ce faire, l’algorithme développé se présente en deux étapes principales : une étape de sélection et de perception des informations les plus pertinentes et une étape de mise à jour de la position estimée et de la fiabilité, cette dernière étape permet également de détecter et réparer ou éliminer les précédentes erreurs. La perception de l’environnement est réalisée à travers différents capteurs associés à des détecteurs spécifiques. L’humain utilise aussi différents capteurs pour se localiser et va intuitivement sélectionner le plus performant, s’il fait jour il utilisera ses yeux, sinon son oreille ou le toucher. Nous avons développé une approche similaire pour le robot qui tient compte des contraintes environnementales et de l’estimation actuelle pour sélectionner à chaque instant l’ensemble capteur, indice de la scène et détecteur le plus pertinent. La phase de perception, étant pilotée par un processus Top-Down, peut bénéficier d’informations déjà connues permettant ainsi de se focaliser sur l’indice recherché et d’améliorer les phases de détection et d’associations de données. Cette approche Top-Down s’appuie sur un réseau bayésien. Ce dernier permet de modéliser les interactions entre les différents événements qui se produisent en gérant l’incertitude. Il permet une prise en compte facile des différents événements. Par ailleurs le réseau bayésien présente une grande flexibilité pour l’ajout d’événements supplémentaires pouvant engendrer des non-détections (tels que dysfonctionnement de capteurs, conditions météorologiques, etc.). Les données de l’environnement sont rendues disponibles grâce à une carte géoréférencée préalablement fournie. Avec le développement de cartes disponibles facilement sur internet, cette façon de faire permet d’exploiter au mieux l’information déjà fournie. L’utilisation d’une carte géoréférencée permet d’avoir un référentiel commun entre tous les véhicules ou éléments de l’infrastructure facilitant ainsi l’échange d’informations et ouvrant du coup la possibilité d’interaction simplifiées dans le cas de flottes par exemple. Les résultats montrent que l’approche développée est pertinente pour une localisation précise et fiable aussi bien statique que dynamique. L’ajout de nouveaux capteurs se fait naturellement et sans nécessiter d’heuristique particulière. La localisation obtenue est suffisamment précise et fiable pour permettre des applications de conduite autonome utilisant, entre autres, cet algorithme. / Vehicle localization is a crucial step in the development of smart vehicles. The research in this domain has been growing in recent years. Generally, the effort is focused on the localization accuracy, we present here a localization method on existing map where the objective is to estimate the robot position not only with accuracy but also with confidence. To achieve this , the algorithm developed has two main steps : one, selection and perception of the most relevant informations and two, position estimation and confidence update. This last step also allows to detect and eliminate the previous errors. Environment perception is well achieved, thanks to different sensors associated with specific detectors. Humans use different senses, shifting automatically in order to localize themselves depending on the situation of the environment, for e.g if there is enough illumination we depend on eyes, else the ear or the touch otherwise. We have developed a similar approach for the robot that takes into account the specific environmental constraints and actual position estimation to select at each instant the most relevant set of sensor, landmark and detector. The perception step, led by a top-down process, can use already known informations allowing a focus on the searched landmark and an improvement of the detection and data associations steps. This top-down approach is well implemented, thanks to a Bayesian network. Bayesian network allows to model the interactions between the different probable events with management of the uncertainty. With this network, it is very easy to take into account those different events. Moreover, a Bayesian network has a great flexibility to take into consideration additional events that can cause false detections (like sensor failure, meteorological conditions and others). The environment data is obtained with a Georeferenced map (from GIS). With the already available maps on the internet, allows to exploit an already existing information. The use of a Georeferenced map facilitates the communication of informations between a vehicle and several other vehicles or with an element of the infrastructure, that can be very useful for multi vehicle coordination, for example. The results shows that the developed approach is very accurate and reliable for localization, whether static or dynamic, and can be applied for autonomous driving. Moreover, new sensors can be added at ease.
66

Stratégie de perception active pour l'interprétation de scènes / Active Perception’s Strategy for scene’s interpretation

Bernay-Angeletti, Coralie 29 June 2016 (has links)
La perception est le moyen par lequel nous connaissons le monde extérieur. C’est grâce à nos perceptions que nous sommes capables d’interagir avec notre environnement et d’accomplir de nombreuses actions du quotidien comme se repérer, se déplacer, reconnaître des objets et autres. Cette perception n’est pas juste passive comme peut l’être une sensation, elle comporte des aspects actifs. En particulier, elle peut être orientée dans un but précis, permettant de filtrer les données pour ne traiter que les plus pertinentes. Si la perception humaine est particulièrement efficace, la perception artificielle, elle, demeure un problème complexe qui se heurte à de nombreuses difficultés. Ainsi, les changements de conditions de perception comme des modifications de l’illumination ou des occultations partielles de l’objet à percevoir doivent pouvoir être gérées efficacement. Pour résoudre ces difficultés, s’inspirer de la perception humaine semble être une piste intéressante. Ce manuscrit propose un système de perception polyvalent et générique reposant sur une stratégie de perception active. Pour ce faire, nous proposons un algorithme Top-Down utilisant un modèle en parties. Le problème de perception est transformé en un problème d’estimation d’un vecteur de caractéristiques. La détection des différentes parties permet de réaliser cette estimation. Le système de perception proposé est un algorithme itératif multi-capteurs. À chaque itération, il sélectionne au mieux, en fonction des objectifs fixés par l’application, la partie à détecter ainsi que les meilleurs capteur et détecteur compatibles. Un réseau bayésien est utilisé pour prendre en compte les événements incertains pouvant survenir lors de ce processus comme la défaillance d’un détecteur ou la non existence potentielle d’une partie donnée. Un processus de focalisation à la fois spatiale et de caractéristiques permet d’améliorer la détection en augmentant le rapport signal sur bruit, en restreignant la zone de recherche pour une partie et en éliminant certains des candidats trouvés. Ce processus de focalisation permet aussi de réduire les temps de calcul et de restreindre l’influence des distracteurs. L’ajout de nouveaux capteurs, détecteurs ou parties se fait simplement. De plus, l’utilisation d’un réseau bayésien permet une grande flexibilité au niveau de la modélisation des événements pris en compte : il est facile de rajouter de nouveaux événements pour obtenir une modélisation plus réaliste. L’algorithme proposé a été utilisé pour plusieurs applications incluant de la reconnaissance d’objets, de l’estimation fine de pose et de la localisation. / Perception is the way by which we know the outside world. Thanks to our perceptions we are able to interact with our environment and to achieve various everyday life actions as locating or moving in an environment, or recognizing objects. Perception is not passive whereas sensations are, it has active components. In particular, perception can be oriented for a specific purpose allowing to filter data and to take care only of the most relevant. If human perception is particularly effective, artificial perception remains a complex problem with a lot of non solved difficulties. For example, changes of perception conditions as modification of illumination or partial occultation of the searched object must be effectively managed. This thesis proposes a system of perception based on a strategy of active perception which can adapt itself to various applications. To do it, we propose an algorithm Top-Down using a part-based model. The problem of perception is transformed into a problem of estimation of a characteristics vector. The detection of the different parts constituting the searched object allows to realize this estimation. The proposed perceptive system is an iterative and multi-sensors algorithm. In every iteration, it selects, at best, according to the application objectives, the part to detect and the best compatible sensor and detector. A bayesian network is used to take into account uncertain events which can arise during this process as detector failure or potential non existing part. A focus process consisting of a spatial focus and of a characteristics focus, improves the detection by restricting the search area, by improving the signal to noise ratio and by eliminating some erroneous candidates. This focus process also allows to reduce computation time and to restrict influence of distractors. Adding a part, a sensor or a detector is simple. Furthermore, the use of a bayesian network allows to be flexible in the events modelisation : it is easy to add new events to obtain a more realistic modelisation. The proposed algorithm has been used for several applications including object’s recognition, fine pose estimation and localization. So, it is multi-purpose and generic.
67

Relações tróficas e limnológicas no reservatório de Itaipu: uma análise do impacto da biomassa pesqueira nas comunidades planctônicas / Trophic and limnological interactions in the Itaipu reservoir: an analysis of the impact of the fishing biomass in the planktonic communities

Rinaldo Antonio Ribeiro Filho 20 November 2006 (has links)
Inúmeros estudos experimentais contribuíram para o desenvolvimento da teoria das redes tróficas lacustres, revelando o importante papel dos peixes, ignorados no campo da limnologia durante décadas. A maioria dos estudos foi desenvolvida na Europa e Estados Unidos e a generalidade da teoria ainda não foi amplamente testada em ambientes subtropicais e tropicais. Apesar das controversas, as hipóteses de cascata trófica e de bottom-up : top-down são os modelos conceituais mais utilizados. Neste contexto, este trabalho baseia-se na hipótese de que as relações tróficas em cascata, relacionadas aos efeitos bottom-up e top-down, podem ser encontradas no Reservatório de Itaipu, inserido em região subtropical. Com base em dados disponibilizados pela Itaipu Binacional, para o período de 1999 a 2004. Análises de Covariância (ANCOVAs) foram realizadas para determinar as relações das variáveis dependentes clorofila-a, cianobactéria e transparência da água sobre as demais variáveis limnológicas. Análises de correlações também foram realizadas para verificar a existência de algum tipo de efeito na cascata trófica. Os resultados obtidos caracterizam o reservatório como mesotrófico, com situações de oligotrofia na zona lacustre. Efeito negativo foi verificado para transparência da água em relação aos sólidos suspensos totais e turbidez. A clorofila apresentou relação positiva com nitrogênio total, mas não para fósforo total. Os peixes onívoros, detritívoros e insetívoros exerceram efeito negativo (controle) na densidade das cianobactérias e na concentração de clorofila. A estimativa da produção de peixes no reservatório foi melhor relacionada com as cianobactérias do reservatório, gerando um modelo estatístico através desta análise. Os efeitos top-down e bottom-up foram confirmados, sendo que as forças top-down foram encontradas apenas no primeiro nível trófico e as demais apresentaram efeito bottom-up. / Many experimental studies contributed for the development of the theory of the lacustrine food web, disclosing the important paper of the fish, for decades ignored by the limnology. These studies, in its majority, had been developed in Europe and North America and the generality of the hypotheses supporting the theory was not tested yet in subtropical and tropical environments. Although controversial, the trophic cascade and bottom-up: top-down hypotheses are the two main conceptual models presently used. This work is based on the hypothesis of the trophic cascade relations, particularly related to bottom-up and top-down effect can be detected in Itaipu Reservoir, a subtropical system. Using the made data available by Itaipu Binacional, from 1999 to 2004. Analyses of Covariance (ANCOVAs) were accomplished to determine the relationships of the dependent variable on the chlorophyll-a, cyanobacterias and transparency of the water (independent variables) and between the other limnologycal variables. Analyses of correlations were also accomplished to verify the existence of some effect type in the trophic cascade. The results show that the reservoir presented mesotrophic, and oligotrophic and characteristics in the lacustrine area. A negative effect was verified between the water transparency in relation to suspended solids and turbid. The chlorophyll presented positive relationship with total nitrogen, but didn\'t present any relationship with the total phosphorus. The omnivorous, and detritivorous and insectivorous fishes presented a negative effect (control) in the cyanobacteria concentrations and chlorophyll. The estimate of the production of fish in the reservoir was better related with the concentrations of cyanobacterias of the reservoir, generating a statistical model through this analysis. The top-down and bottom-up effect had been confirmed, the forces top-down had been found only in the first trophic level, and the others presented bottom-up effect.
68

Konsten att berätta : -En fallstudie om narrativ och delaktighet / The art of telling : -A case study on narrative and participation

Nilsson, Andreas, Modig, Miriam January 2022 (has links)
Sammanfattning  Denna uppsats behandlar förhållandet mellan medborgardialog och offentlig konst utifrån en statligt ägd satsning vid namn Äga rum: Konst händer som Statens konstråd fick i uppdrag att genomföra. Satsningen syftade till att göra civilsamhället till beställare av offentlig konst och öka den demokratiska delaktigheten. Uppsatsen bygger på en fallstudie som involverar dokumentanalys, platsbesök och intervjustudier utifrån begreppen medborgardialog, delaktighet, tillit, och narrativ.  En stor del av det offentliga rummet består utav den offentliga konsten. Det offentliga rummet är en viktig del av det samhälle vi lever i och ska vara en demokratisk plats där invånaren ges möjlighet att påverka utvecklingen av den gemensamma miljön. I Sverige har den folkliga tilliten till den representativa demokratin sjunkit, ett problem som man vill lösa genom medborgardialog. Den här uppsatsen undersöker hur konstprojektet Konst händer i miljonprogramsområdet Gamlegården, Kristianstad lyckades med att föra dialog med medborgarna. Svårigheterna med medborgardialog belyses, bland annat utifrån narrativens kraft att påverka där olika maktperspektiv och uppifrån styrda, så kallade top-down satsningar lyfts. Utifrån vår undersökning så ser vi att det krävs mer än bara en önskan om att involvera medborgare för att faktiskt involvera dem. När de involveras bör delaktigheten utgå ifrån en reell makt att påverka annars riskerar det medborgerliga engagemanget att fallera. Samtidigt är det viktigt att möjligheterna till inflytande möjliggörs för alla medborgare så att det inte är samma grupper och personer som alltid får komma till tals. / Abstract  This essay analyses the relationship between citizen dialogue and public art through a state-owned initiative called Äga rum: Konst händer which the Swedish Arts Council was commissioned to perform. The initiative aimed to make the civil society the stakeholder of public art and increase democratic participation. The thesis is based on a case study that involves document analysis, site visits and interview studies based on the concepts of citizen dialogue, participation, trust and narrative.  A large part of the public space consists of public art. The public space is an important part of the society we live in and should be a democratic place where the citizens are given the opportunity to influence the development of the common space. In Sweden, the trust in representative democracy has weakened, a problem that aims to be solved through citizen dialogue. This essay examines how the art project Konst händer in the million program area of Gamlegården, Kristianstad succeeded in conducting a dialogue with the citizens. The difficulties with citizen dialogue are highlighted, among other things based on the power of narrative to influence, different power perspectives and the so called top-down initiatives. Based on our survey, we see that it takes more than just a desire to involve citizens to actually involve them. When they are involved, participation should be based on real power to influence, otherwise the civic participation risks failing. At the same time, it is important that the opportunities for influence are made for all citizens so that it´s not the same groups and people who always get their voices heard.
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"En liten del i ett stort sammanhang" : – En kvalitativ studie om implementering av metoden Multisystemisk terapi inom socialtjänsten / "A small part of a large context" : - A qualitative study on the implementation of the method Multisystemic therapy in social services

Björkstrand, Marie January 2016 (has links)
Syftet med studien var att belysa personals erfarenheter och upplevelser av implementeringen av den evidensbaserade metoden Multisystemisk Terapi (MST) inom Socialtjänstens öppenvård. Vetenskapstraditionen utgår från den tolkande hermeneutiken med inspiration av ett fenomenologiskt perspektiv. Undersökningen bygger på fyra semistrukturerade intervjuer av personal på olika organisatoriska nivåer. En slutsats är att implementeringsprocessen är inbyggd i MST som koncept och i den organisation som finns runt omkring. Styrningen verkar mestadels ha varit en växelvis påverkan. Detta har tillsammans med andra gynnande faktorer som bl.a. tro på metoden, modelltrogenhet, information och stödjande samarbete mellan alla led från politiken, inom organisationen och med hela MST-organisationen överbryggt hinder och varit en stor bidragande faktor till att implementeringen kan anses lyckosam. Metoden används till största delen tillfredsställande. Trots vissa hinder upplever personalen att de själva och familjerna på det stora hela är nöjda med MST som metod och de resultat som den visar. Personalen utvecklas i arbetet med metoden och familjer har rekommenderat andra familjer MST.
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An investigation into sustainable forest policies and practices in Syria

Al Berni, Rim Rateb January 2010 (has links)
Appreciation of how forest land can be managed in a sustainable way in arid and semi-arid zones (ASAZs) of centralized countries is limited. Accordingly, this thesis seeks to analyse the role of government and communities, including women, in the formulation and implementation of sustainable forest management (SFM) policy and practices in the semi-arid environment of Syria where such land is limited in extent (e.g. 3% forest and 57% rangeland) and yet where its high biodiversity value is of international significance. The thesis employs a variety of methods: a case study approach (Syria); a questionnaire (i.e. 142 respondents); face-to-face interviews (i.e. 26 interviewees); participant observation and secondary data. The SFM model was used to organise and analyse the influences of environmental, economic, social, cultural and political issues on the state of forest land in Syria. Three contrasting forest areas were selected for detailed analysis at local level: Al Foronloq had the Arab Institute of Forestry close by and the area had a high biodiversity value for landscape; Abo Kbeis contained key genetic resources and a number of women there had been trained in forest management and Abd Aziz Mountain was characterised by rangeland with traditional grazing plus a very arid environment. The main results obtained from census data confirmed that Syrian forest lands have diminished considerably since 1900 with regard to their geographical extent due to agricultural development, expansion of rural-urban settlements as well as of agricultural land onto Syrian forest land. On a more general level, the political issues in Syria (i.e. centralization and independency of the country) demand development of the internal resources of the country, such as agricultural production, in order to cover the needs of human maintenance. Scrutinising forest documentation and using results of face-to-face interviews, it was found that there were considerable changes in forest policies in terms of forest protection and plantation. In addition, there was a recent indication of adopting SFM principles in the case study area, largely as a result of action by agencies external to Syria at the national level, and the new role of NGOs in forest management at the local level. The increasing level of awareness of environmental problems; the capacity of institutions; community participation in natural resources management and achieving international agreements were also found to be paramount in any contracts between the Syrian government and other organisations. This thesis, at the local level, showed that respondents in the mountains (in the Abd Aziz Mountain (AAM) study area) seemed to be older, poorer, mostly with non-educated background, with more than three children, than in the Al Foronloq (AF) and Abo Kbeis (AK) study areas. Respondent groups in AAM were found to be more dependent upon forest resources than respondents in AF and AK; and they occupied land illegally because of their mission to develop agricultural activities, including grazing. The study confirmed that educated households in AF and AK use forest resources more than non-educated households. Conversely, non-educated households in AAM suffer from gaining a local income which may in turn affect their attitudes and behaviours in using forest resources; and as consequence, householders suffering from financial problems may be less aware of the importance of forest protection and try to solve their individual needs by increasing the pressures on the forest resources. The major constraints affecting the formulation and implementation of SFM policy are insufficient financial resources, inadequate management from national to regional and local levels; the limitations are also related to local communities’ attitudes and ignorance of the role of women in forest management. This thesis found that the contribution of women in the labour force at the local level was high in Lattakia (Al Foronloq study area) compared with other study areas (e.g. 32.9% in Lattakia against 13.4% in Hamah and 18.8% in Alhasake) (UNDP: Syrian Human development, 2005); although, there was a significant relationship between income level, family size and women’s contribution in forest management at the local level and no significant relationship with the educational level. On a more specific level, the role of religious faith in AK affects the contribution of women in the society and the workplace generally and in forest management in particular. Finally, the application of the SFM model in this study provided a flexible approach for analysis of complicated interactions between the government and communities. It also provided a comprehensive framework for different types of analytical purposes. Each of the three main components (issues, state and political decisionmakers) was divided into several sub-components which facilitate the explanation and identification of the complexities affecting the formulation of SFM policy and the implementation of such policy. It helped to provide a set of policy recommendations which may help to increase future community participation in forest management and reduce the influences of community pressures on forest resources in Syria.

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