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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.
101

Observer error in identifying species using indirect signs: analysis of a river otter track survey technique

Evans, Jonah Wy 17 September 2007 (has links)
Indirect signs of species presence (e.g., tracks, scats, hairs) are frequently used to detect target species in occupancy, presence/absence, and other wildlife studies. Indirect signs are often more efficient than direct observation of elusive animals, making such signs well suited for long-term and broad-scale monitoring programs. However, error associated with misidentification of indirect signs can be high, and should be measured if meaningful inferences about population parameters are to be made. This study addressed the need for systematic approaches to estimate and minimize variation due to observer error in identifying indirect signs. I reanalyzed data from 4 replicates of a presence/absence survey of northern river otters (Lontra canadensis) that had been conducted by Texas Parks and Wildlife Department (1996-2003). Sixteen observers had recorded tracks at sample points under bridges (n = 250) distributed throughout 27 counties in the Piney-Woods ecoregion of east Texas. My objectives were to 1) determine if observers were a source of bias in the survey, 2) estimate the proportion of error associated with track identification skill, and 3) evaluate the use of an international certification procedure that measured observer tracking skill. The null hypothesis that observers had no effect on the variation in reported sign was rejected. Indeed, binary logistic regression tests indicated that observers were significantly associated with variation in reported track presence. Observers were not randomly distributed among bridge sites, and therefore were significantly correlated with 4 habitat variables that may have influenced heterogeneity in otter occupancy and probability of detection (watershed, vegetation-type, water-type, bridge-area). On average, experienced observers (n = 7) misidentified 44% of otter tracks, with a range of 0% to 100% correct detection. Also, 13% of the tracks of species determined to be 'otter-like' were misidentified as belonging to an otter. During the certification procedure, participants misidentified the tracks of 12 species as otter. Inaccurate identification of indirect signs is a likely source of error in wildlife studies. I recommend that observer skill in identification of indirect signs be measured in order to detect and control for observer bias in wildlife monitoring.
102

1990 m. gimusių vaikų fizinės būklės ypatumai, raidos takai ir veiksniai augimo laikotarpiu (išilginis auksologinis Vilniaus miesto ir rajono vaikų tyrimas) / Physical status, growth tracking and growth factors of children born in 1990 (longitudinal auxological study of children from Vilnius city and Vilnius region)

Suchomlinov, Andrej 02 March 2012 (has links)
Darbe tirti 1990 metais gimusių Vilniaus miesto ir rajono vaikų augimo ypatumai nuo gimimo iki brendimo pabaigos, individualių raidos takų įvairovė, etniniai, socialiniai ir ekonominiai augimo veiksniai, „nepriklausomybės kartos“ vaikų fizinės būklės epochiniai pokyčiai ir augimo tendencijos. Šis darbas – vienas pirmųjų mūsų šalies auksologinių tyrimų, kuriame buvo nustatyta vaikų augimo takų individuali įvairovė nuo gimimo iki aštuoniolikos metų amžiaus. Šiame longitudiniame 1990 m. (atgavus Lietuvos nepriklausomybę) gimusių vaikų tyrime buvo naudojamas ambulatorinių kortelių metodas, ištirti jo privalumai ir trūkumai. Nustatyta, kad profilaktinių vaikų apsilankymų poliklinikoje dažnis susijęs su vaiko amžiumi, gyvenamąja vieta (miestas arba kaimas), atstumu iki poliklinikos ir vaiko gimimo eiliškumu. Vaikų augimo rodiklių įrašai ambulatorinėse kortelėse palyginti tikslūs ir tinkami auksologinei analizei. Darbo rezultatai patvirtino, kad ūgio ir kūno masės indekso raidos takų kaita augimo laikotarpiu yra normalus reiškinys, priklauso nuo amžiaus ir lyties. Po 1990 m., t.y. didelių politinių, socialinių ir ekonominių pertvarkų laikotarpiu vaikų fizinių rodiklių augimas atsiliko palyginus su stabiliais šalies raidos laikotarpiais. Neigiami šio laikotarpio vaikų augimo pokyčiai buvo grįžtami. Nustatyti etniniai ir socialiniai abiejų lyčių vaikų fizinės būklės skirtumai. Pagrindiniai vaikų fiziniai rodikliai (ūgis, svoris, kūno masės indeksas) per pastaruosius dešimtmečius... [toliau žr. visą tekstą] / Physical status of children born in 1990 in Vilnius city and region from birth up to the end of puberty, the variety of individual growth tracks, ethnic and socio-economic growth factors, the epochal changes in growth and growth patterns of the “generation of independence” were investigated. This study was one of the first to establish the variety of individual growth tracks from birth to the age of eighteen years. In this longitudinal study of children born in 1990 (the year Lithuania restored its independence) the personal health records’ analysis was used and its benefits and drawbacks were investigated. The age of children, the place of residence (urban or rural), the distance to the outpatient clinic and the ordinal number of a child in a family were associated with the regularity of visiting the outpatient clinic. Children's growth indices in personal health records were rather accurate and suitable for auxological analysis. The results of this study confirmed that children normally changed their growth tracks for height and body mass index during the growth process. These changes were associated with their age and sex. Retardation in growth of children was related to the political and socioeconomic changes in Lithuania after 1990. Nevertheless, this retardation was reversible. Ethnic and socioeconomic differences in physical status of both boys and girls were established. The main body size indices (height, weight and body mass index) of children remained almost... [to full text]
103

Řešení zpřístupnění pozemků v komplexní pozemkové úpravě

STRADOVÁ, Šárka January 2016 (has links)
This diploma work deals with the evaluation of road net within the complex of estate layout and focuses on cart tracks. In the first part there is an overview of literature, next it describes estate layout and finally it focuses on road net. The cadastral area Dlouhá Stropnice in Southbohemian region has been chosen for this work. The detailed description of this area has been elaborated. The main point was the analysis of road net.
104

Análise geoambiental do mirante do marco geodésico na borda da Chapada dos Guimarães - MT

Marcello, Aline Maiara 05 June 2014 (has links)
Submitted by Valquíria Barbieri (kikibarbi@hotmail.com) on 2018-03-28T21:35:35Z No. of bitstreams: 1 DISS_2014_Aline Maiara Marcello.pdf: 12172192 bytes, checksum: c31774ffe0f50a7fbcdfa50d3312a1eb (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2018-04-17T15:18:54Z (GMT) No. of bitstreams: 1 DISS_2014_Aline Maiara Marcello.pdf: 12172192 bytes, checksum: c31774ffe0f50a7fbcdfa50d3312a1eb (MD5) / Made available in DSpace on 2018-04-17T15:18:54Z (GMT). No. of bitstreams: 1 DISS_2014_Aline Maiara Marcello.pdf: 12172192 bytes, checksum: c31774ffe0f50a7fbcdfa50d3312a1eb (MD5) Previous issue date: 2014-06-05 / CAPES / Esta pesquisa teve como finalidade contribuir para a conservação da borda da Chapada dos Guimarães, e refletir sobre as necessidades de alternativas de uso nos locais de atrativo turístico na região. Dessa forma, entendeu-se que por meio de um estudo geoambiental seria possível contribuir de forma efetiva com melhor conhecimento da área. O projeto concebido para ser executado em 18 meses entre os anos de 2012 e 2014 teve como principal objetivo, realizar uma análise geoambiental através da identificação da cobertura pedológica e processos erosivos nas vertentes, bem como suas relações com o seu comportamento hídrico, relevo e substrato rochoso, visando caracterizar os diferentes comportamentos do local e apresentar subsídios e critérios para o desenvolvimento de um plano de manejo. A pesquisa concentrou-se no Mirante do Marco Geodésico em Chapada dos Guimarães-MT, onde foram realizadas 05 etapas de campo para o reconhecimento do local e delimitação da área, realização da topossequência e observação e caracterização dos processos erosivos. O conjunto de informações obtidas pelas observações diretas nos trabalhos de campo aliado a base metodológica adotada, permitiu a compreensão dos impactos provocados pelas ações humanas aceleradoras dos processos da dinâmica superficial. No estudo de caso do Mirante, observou-se que a falta de planejamento contribui para alteração do equilíbrio dinâmico do ambiente. Foram identificadas 03 manifestações principais de erosão: uma na principal trilha turística local, outras duas em linhas de talvegue, sendo que uma delas já se encontra estabilizada e a outra se encontra no traçado de uma antiga trilha. / This research aimed to contribute to the conservation of the edge of Chapada dos Guimarães, and reflect on the need for alternative use in places of tourist attraction in the region. Thus, it was understood that through a geo-environmental study would be possible to effectively contribute to better knowledge of the site. The project is designed to be executed in 18 months between the years 2012 and 2014 had as its main objective, perform a geo-environmental analysis by identifying the soil cover and erosion processes on slopes, as well as their relationships with their water behavior , topography and substrate rocky, to characterize the different behaviors of local and present subsidies and criteria for the development of a management plan for the site. The research focused on the “Lookout Marco Geodésico em Chapada dos Guimarães-MT”, where 05 steps field for the recognition of local and delineation of the field, and realization of topossequence observation and characterization of the erosive processes were performed. The set of information obtained by direct observations during field work combined with theoretical basis adopted, allowed understanding the impacts of human actions accelerating the natural dynamic processes of surface, often in association with concentrated surface water flow as factors generating erosions. In the case study of the Lookout, it was observed that the lack of planning contributes to the dynamic balance of the environment. 03 major erosion events were identified: one in the main local tourist track, two in thalw
105

Management des processus collaboratifs dans les systèmes PLM / Collaborative processes management within PLM systems

El Kadiri, Soumaya 04 December 2009 (has links)
La tendance actuelle des organisations à développer des collaborations avec différentes parties prenantes a pour objectif de répondre à une complexité de plus en plus importante des produits et de favoriser l'innovation ; le tout sous de fortes pressions d'un environnement économique, liées aux exigences du développement durable, de l'accélération des cycles de vie, des normes qualité, etc. Les SIP tendent à garantir une transversalité entre l'ensemble des phases du cycle de vie produit ; répondant ainsi aux besoins d'amélioration de la qualité produit, de maîtrise des processus et de réduction des délais, tout en favorisant la collaboration. La complexité des processus collaboratifs liée à la gestion du cycle de vie du produit ne peut faire l’économie d’une réflexion sur les ressources engagées au regard des objectifs poursuivis, ni même d’une balance économique globale des coûts supportés. Ainsi les critères d’efficacité et d’efficience s’ajoutent aux critères les plus traditionnels du temps imparti et du degré de qualité visé. L'objectif de cette thèse consiste à définir une démarche méthodologique et applicative pour répondre à la question suivante : "Comment instrumenter le SIP pour analyser les activités menées au sein du système et déceler les freins au travail collaboratif ?". Ainsi, nous présentons dans cette thèse un cadre méthodologique et architectural permettant d'assurer un pilotage des processus collaboratifs dans les SIP. Il s'agit entre autre de mettre en place une expérience d'observation basée sur l’ingénierie des traces ; et de mener une réflexion sur la définition d'indicateurs permettant de mettre en place un contrôle de l'activité collaborative. La mise en œuvre effective de ces actions implique la définition d’une architecture complémentaire et générique adaptée à l'environnement du SIP. Finalement, le développement d'un prototype, intégré par la suite au SIP @udros, nous a permis de valider le cadre méthodologique et applicatif de cette thèse. / The current trend of organizations to develop partnerships with various stakeholders aims to respond to a rising complexity, of products and to foster innovation; all under great pressures of an economical environment, related to sustainability requirements, lifecycle acceleration, quality standards, etc. PLM systems tend to ensure the transversality within all the stages of product lifecycle; meeting the needs of product quality improvement, process control and delays reduction, while fostering collaboration. The complexity of collaborative processes related to the product lifecycle management cannot lean only on the engaged resources, or on the global balance between costs, budget, and receipts. Then efficacy and efficiency criterions come on top of the traditional ones (quality level, time, etc.). This thesis aims to propose a methodological and applicative approach responding to the following research question: “How can PLM System be « instrumented » in order to analyze the collaborative activities and to reveal the brakes causes?” We present in this thesis a methodological and architectural framework to ensure a collaborative process management in PLM System. The methodological framework leans on observation experiences based on tracks engineering (tracks generated by PLM system) and indicators definition supporting the control of the collaborative activity. The principal objective is to reduce risks by reacting in real time to the incidents or dysfunctions that may occur. The effective implementation of these actions involves the definition of a generic and complementary architecture suitable to the environment of the system. Finally, the development of a prototype, integrated then to the system @udros, allowed us to validate the methodological and architectural framework of this thesis.
106

Terracetes de pisoteio de gado e mudanças morfo-pedológicas em vertente amostral na bacia hidrográfica do rio Jacareí, Serra da Mantiqueira-SP / Cattle-tracks and morpho-pedological changes in slope samples in the hydrographic basin of Jacarei River, Serra da Mantiqueira-SP

Larissa Giroldo 29 November 2013 (has links)
A dissertação de mestrado desenvolvida tem como objetivo colaborar com a avaliação conceitual da forma erosiva terracete de pisoteio de gado, ainda pouco desenvolvida e, avaliar as perturbações do meio físico associadas ao pisoteio de gado. O objetivo da pesquisa torna-se relevante ao constatar que a temática desenvolvida é objeto de poucas produções acadêmicas. Além disso, no caso brasileiro, a grande área de terras utilizadas para a pastagem gera a necessidade de entendimento do funcionamento dessa paisagem antrópica para se produza formas corretas de manejo e possíveis restrições para o uso do solo a fim de evitar perturbações no meio físico difíceis de serem revertidas. Para elaborar a análise proposta, utilizou-se como embasamento teórico-metodológico a Geomorfologia Antropogênica em que a sociedade humana é inserida como agente de formação do relevo mesmo que indiretamente como no caso de áreas para a pastagem. Na perspectiva da Geomorfologia Antropogênica é necessário uma abordagem multiescalar para entender a magnitude das perturbações geradas no meio físico pelo ser humano. A primeira linha de investigação para o desenvolvimento da dissertação foi a pesquisa bibliográfica multilíngüe sobre o verbete terracete de pisoteio de gado. Completando a pesquisa bibliográfica, a segunda linha de investigação foi a analise em campo das perturbações do meio físico associadas aos terracetes de pisoteio de gado, com parâmetros físicos do solo e morfológicos da vertente. Como área de estudo, foi escolhida uma vertente amostral da parte rural da cidade de Joanópolis SP. A vertente amostral pertence ao Planalto Atlântico com solos pouco espesso e uso agrícola intensa, possibilitando a comparação entre do trecho da vertente preservado e o trecho antrópico com pastagem. Na vertente amostral foram aplicadas técnicas de campo reconhecidas academicamente. Como procedimento inicial utilizou-se o pantômetro por permitir o cálculo preciso da declividade. Com a análise inicial em campo e a elaboração do perfil topográfico, foram selecionados três pontos de controle para a medição de resistência a penetração; medição da densidade do solo e; a análise morfológica do solo. Os resultados evidenciaram que as perturbações geomorfológicas e pedológicas criadas pelo rebanho bovino são intensas e de diversos tipos. O caminhar do gado também promove a exposição do solo, visto que dificulta ou impede o crescimento da pastagem, pois ao compactar o solo, gera resistência a penetração superior ao limite de crescimento radicular. A compactação do solo é mais profunda que o horizonte A e, em solos pouco espessos, como o neossolo estudado nessa pesquisa, o terracete de pisoteio de gado tem um limite físico para a sua profundidade a rocha parental. / The developed dissertation aims to collaborate with the conceptual evaluation of cattle-tracks erosive form, which studies are still little developed, and to evaluate the physical disturbance associated with cattle trampling. The objective of this research is relevant to add the developed subject itself, which has been presented in few academic productions. Besides that, in Brazilian case, the large land area used for grazing, generates the necessity to understand the functionality of the anthropic landscape, in order to produce correct forms of handling and possible use of land restrictions to avoid disturbances in the physical environment, which are difficult to be reversed. Composing the proposed analysis, it was applied as theoretic and methodological praxis the Antropic Geomorphology where in the society is an agent of relief formation even indirectly, like the case of grazing. In perspective of anthropic geomorphology is necessary a multi-scale approach to understand the magnitude of the disturbance generated in the physical environment caused by human being. The first investigation line for the development of this dissertation was the bibliographic multilingual search about the word cattletracks. In completion of the bibliographic search, the second investigation line was the analyses in field about the disturbance in physical environment associated to the cattle-tracks, with physical soil parameters and morphological slope parameters analyses. As study area, a sample slope of Joanópolis rural area was selected. The sample slope belongs to Atlantic plateau with shallow soil e intense agricultural use enabling comparison between the segment with cover forest and segment with grazing. In the sample slope, it was applied field techniques academical lyre cognized. And as an initial procedure it was used the pantometer, which allows accurate calculation of slope. Up the initial field analysis and profile elaboration, three control points were selected in order to measure the penetration resistance, measure the soil density and morphology. The results showed that geomorphological and pedological disturbance created by cattle was intense and from several types.The cattle grazing causes naked soil, because hinders or prevents the growth of pasture, therefore compacts the soil, creates penetration resistance upper to the limit root growth. The soil compact is deeper than the horizon A and, in shallow soil, as the soil of this research, the cattle-tracks has a physical limit for its deepness, which is the parent rock.
107

Feuilletages mesurés et feuilletages transversalement affines / Measured foliations and affine foliations

Said, Ahmad 26 September 2013 (has links)
On étudie les feuilletages transversalement affines des surfaces compactes, avec ou sans bord. On met en relation plusieurs méthodes de construction de tels feuilletages: application de premier retour et échanges d'intervalles affines (pour un feuilletage pas nécessairement orientable) ; mesure brisée sur un réseau ferroviaire; feuilletage mesuré sur le revêtement universel avec automorphismes du revêtement agissant de manière affine ; recollement le long de leur bord de surfaces munies de feuilletages affines. On étudie l'injectivité des applications à image dans l'espace des classes d'équivalence des feuilletages transversalement affines qui résultent de ces diverses constructions. / We study the affine foliations on a compact surface in both cases : with a boundary and without a boundary. We connect between several ways of constructing these foliations. These ways are the first return map, the affine interval exchange (for a foliation which is not necessarily orientable), the train tracks with broken measures, the gluing affine foliations on surface with boundary, and the measured foliation on the universal covering with covering translation acting in affine ways. We study the injectivity of the applications with image in the space of equivalence classes of affine foliations which result from these various constructions.
108

Réponse de la circulation atmosphérique aux forçages anthropiques : des modes annulaires aux dépressions synoptiques / Atmospheric circulation response to anthropogenic forcings : from annular modes to storm tracks

Oudar, Thomas 10 November 2016 (has links)
L'étude de la variabilité climatique dans les moyennes et hautes latitudes est très complexe, principalement en raison des nombreux mécanismes physiques mis en jeu. Cette variabilité climatique résulte de deux contributions majeures : la variabilité interne associée à des processus internes au système climatique et la variabilité forcée qui est liée aux forçages externes, qui peuvent être d'origine naturelle (comme le volcanisme, les aérosols naturels) ou anthropique (GES, aérosols anthropiques). Ces forçages externes jouent un rôle important sur le climat et sa variabilité. Le défi de la recherche climatique est de comprendre leurs effets sur le climat et leurs rôles face à la variabilité interne. Cette thèse a comme objectif une meilleure compréhension des rôles respectifs de la variabilité interne et des différents forçages externes sur la variabilité passée de la circulation atmosphérique dans les deux hémisphères et de l'activité synoptique associée, ainsi que de leur évolution pour le climat futur en utilisant des ré-analyses atmosphériques et des simulations issues du modèle de climat CNRM-CM5. Nous nous sommes intéressés dans un premier temps à l'étude des changements des modes annulaires dans les hémisphères nord et sud, appelés respectivement NAM (Northern Annular Mode) et SAM (Southern Annular Mode). Nous montrons que la tendance positive observée du SAM sur la période 1960-1990 en été austral est bien reproduite par le modèle. Cependant, celle-ci est reproduite lorsque la diminution d'ozone stratosphérique et l'augmentation des gaz à effet de serre sont toutes deux prescrites au modèle, alors que certaines études suggéraient qu'elle était principalement expliquée par la seule présence de l'ozone. Nous nous sommes ensuite focalisés sur les changements de circulation \linebreak atmosphérique dans l'hémisphère nord. Ceux-ci sont plus complexes que dans l'hémisphère sud. En effet, l'augmentation des GES provoque un réchauffement global différent suivant l'altitude : maximum dans la haute troposphère tropicale ainsi qu'aux hautes latitudes en surface. Ce dernier est en réalité expliqué par la fonte de la banquise Arctique. De nombreux processus physiques et de nombreuses rétroactions sont mis en jeu et rendent la compréhension des changements compliquée. Pour cela, nous avons mis en place un protocole expérimental avec le modèle couplé CNRM-CM5 pour séparer l'effet direct des GES (réchauffement de l'atmosphère) de l'effet indirect (fonte de la banquise Arctique et rétroaction sur l'atmosphère). Cette fonte est responsable de l'augmentation des flux de chaleur entre l'océan et l'atmosphère qui perturbe ensuite la circulation atmosphérique. Nous montrons que la diminution de glace de mer Arctique pourrait être à l'origine de la réponse barocline dans l'hémisphère nord. Enfin, la dernière partie de cette thèse a fait l'objet d'une étude plus spécifique, puisque l'on s'est intéressé aux évolutions passée et future des dépressions atmosphériques nord Atlantique. De nombreuses incertitudes persistent en raison de processus complexes mettant en jeu la vapeur d'eau, le gradient méridien de température et la stabilité statique. Nous retrouvons la réponse tripolaire dans le RCP8.5, mentionnée dans le 5\up{ème} rapport du GIEC, qui correspond à une diminution dans la partie sud du domaine Atlantique nord et la mer Méditerranée, une augmentation sur les îles Britanniques et la Scandinavie et une diminution à l'est du Groenland. Nous montrons que ce signal est peu robuste sur la période dite historique en raison de la forte variabilité interne associée aux systèmes dépressionnaires. / Climate variability in mid and high latitudes is very complex due to numerous physical mecanims implied. This climate variability can be decomposed into 2 components : the internal variability associated with internal processes and the forced variability linked to the external forcings which can be natutal (volcanism, natural aerosols) or anthropogenic (greenhouse gases, anthropogenic aerosols). These external forcings play a crucial role on the climate and its variability. The challenge in the climate research is to understand their effects on the climate and their roles relatively with the internal variability. The objective of this thesis is a better understanding of the respective roles of internal variability and forced variability on the past and future atmospheric circulation in both hemispheres characterized by the annular mode and the synoptic activity associated using atmospheric reanalysis and experiments performed with the coupled climate model CNRM-CM5. First, we focus on the annular mode changes in both hemispheres, named the NAM (Northern Annular Mode) and the SAM (Southern Annular Mode). We show that the observed positive trend of the SAM in the 1960s in austral summer is well reproduced by the climate model. However, contrarily to other studies which suggest that this positive trend can be explained by only stratospheric ozone depletion, it is reproduced in the CNRM-CM5 model when the ozone depletion and greenhouse gases (GHG) increase are both prescribed. Then, we investigate the changes in the Northern Hemisphere atmospheric circulation. These are more complex than in the Southern Hemisphere. Indeed, the increase of GHG in the atmosphere causes a general global warming maximum in the tropical high troposphere and over the pole at the surface which is mainly explained by Arctic sea ice loss. So the understanding of the changes is very complex due to several physical processes and retroactions. Thus, we have conducted a protocol with the coupled climate model CNRM-CM5 in order to assess the respective role of Arctic sea ice loss and GHG increase. Arctic sea ice loss is reponsible for an increase in the heat flux between the atmosphere and the ocean which modify the atmospheric circulation. We show that Arctic sea ice loss can cause the baroclinic response in the Northern Hemisphere. Finally, the last part of the thesis is the study of past and future changes in the North Altantic storm-tracks. There are still sereval uncertainties because of the complex processes involving the water vapour, the meridional temperature gradient and the static stability. We find the tripolar response, already found by other studies, consisting of a significant decrease in the south of the basin and over the Mediterranean sea, a small increase over the British Isles, and a decrease east of the Greenland. We show that the signal in the historical period is not robust, due to large chaotic variability associated with storms.
109

Quelles méthodes pour la gestion durable de la ressource des plantes aromatiques et médicinales ? : Analyse des inventaires historiques en Albanie, modélisation des habitats à partir des traces GPS des cueilleurs et construction d’un observatoire / What methods for the sustainable management of the resource of medicinal and aromatic plants? : Analysis of historical inventories in Albania habitat modeling using GPS traces pickers and the construction of an observatory

Hoxha, Valter 16 December 2014 (has links)
Les plantes aromatiques et médicinales en Albanie constituent un secteur économique qui exerce de fortes pressions sur la ressource naturelle et entraine la dégradation des habitats des plantes, voire même les expose à des risques d'extinction. L'objectif global de la thèse est de proposer de nouvelles approches complémentaires pour améliorer la base de connaissance sur la ressource des PAM en Albanie. La première partie de la thèse traite du travail qu'il a fallu réaliser sur l'existant (inventaires et études) pour en tirer les enseignements et détecter les manques éventuels. Le travail sur les archives albanaises recouvrant la période allant de 1920 à 1986 et différentes études réalisées entre 1988 et 2010 ont permit de cerner les différents dispositifs de gestion de la ressource. Une partie des données historiques exploitables a été rassemblée et structurée sous forme de base de données. La seconde partie de la thèse propose une méthode de modélisation de l'habitat exploitée à partir des traces GPS des cueilleurs en utilisant essentiellement des concepts issues de la « Time Geography ». La collecte de l'information repose sur une approche participative (crowdsourcing) associant les cueilleurs en tant que contributeur d'information. Les traces GPS sont traitées et analysées par un modèle qui met en œuvre un ensemble de filtres pour ne retenir que les portions de trace qui appartiennent à l'action de cueillette stricto sensu. Déterminer l'action de cueillette reviens à détecter indirectement l'emplacement d'une plante. L'application successive des filtres de la vitesse instantanée, de la densité spatio-temporelle, de la surface et de la moyenne des variations d'angles sert à modéliser la zone de cueillette (zc) qui par agrégation à différentes échelles permet de reconstituer l'habitat exploité. La construction du modèle théorique a été traduite en langage SQL et implémentée dans une base de données spatiale pour faciliter le traitement automatisé des données. Ce modèle a été testé sur trois types plantes : la sauge, le romarin et le tilleul. La comparaison des résultats de la modélisation, représentés sous forme de cartographies synthétiques, d'un côté, avec les données terrains (photos géoréférencées) de l'autre, ont permis de faire évoluer le modèle dans un premier temps et de valider les résultats dans un second temps. La construction d'une base de données capable d'intégrer le résultat du traitement des traces GPS et les données historiques d'archives, tout en les restituant sous forme de vues cartographiques ou statistiques permet de démontrer qu'il est possible de faire cohabiter et de croiser des données provenant de sources d'origine et de nature différente. Malgré un nombre d'expérimentions limités, le modèle couplé à la base de données «BD OPAM», jette les premières bases d'un observatoire préfigurant la gestion évolutive des PAM. / Medicinal and aromatic plants in Albania is an economic sector that exerts great pressure on the natural resource and causes the deterioration of the habitats of plants and even puts them at risk of extinction. The overall aim of the thesis is to provide new complementary approaches to improve the knowledge base on PAM resource in Albania. The first part of the thesis deals with the work that had to be made on the existing (inventories and studies) to draw lessons and identify potential gaps. The Work on the Albanian archives covering the period from 1920 to 1986 and various studies conducted between 1988 and 2010 have made it possible to identify the various devices of resource management. A harvestable part was collected as historical data and structured as a database. The second part of the thesis proposes a method of habitat modeling operated from GPS traces of the gatherers using mainly concepts from the "Time Geography." The collection of information is based on a participatory approach (crowdsourcing) involving gatherers as information contributor. GPS tracks are processed and analyzed by a model that uses a set of filters to select only those portions that belong to trace's action of picking in strict sense. Determine the action of gathering come back to indirectly detect the location of a plant. The successive application filters of the instantaneous speed, of the spatio-temporal density, of the surface and the mean variation of angles used to model the collection area (zc) that the aggregation at the different scales used to reconstruct the exploited habitat. The construction of the theoretical model has been translated into the SQL language and implemented in a spatial database to facilitate automated data processing. This model has been tested on three herbs: sage, rosemary and linden. Comparison of the results of modeling, represented as synthetic maps on one side, with the land data (photos georeferenced) on the other, have helped to change the model initially and validate results a second time. Building a database that can integrate the treatment outcome of GPS tracks and historical data archives, while restoring the form of map views or statistics used to demonstrate that it is possible to integrate and crossing data from sources of different nature and origin. Despite a limited number of experimenting, the coupled to the database "BD OPAM" model, laying the first foundations of a monitoring foreshadowing adaptive management of PAM.
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Estudos de "annealing" de traços de íons e traços de fissão em muscovita / Annealing studies of ion tracks and fission tracks in muscovite

Lixandrão Filho, Arnaldo Luis, 1983- 31 August 2018 (has links)
Orientador: Sandro Guedes de Oliveira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-31T19:22:36Z (GMT). No. of bitstreams: 1 LixandraoFilho_ArnaldoLuis_M.pdf: 11489211 bytes, checksum: 0e5e2fdcd3551b722c60d418964284ee (MD5) Previous issue date: 2016 / Resumo: O trabalho consistiu em estudar a muscovita como termocronômetro. Por ter pequena quantidade de urânio, abaixo de 5 partes por milhão, a utilização direta é inviável. Dessa forma, irradiamos placas de muscovita com íons de $^{238}U$ moderados por folhas de alumínio (resultando em diferentes energias) e com diferentes ângulos de incidência, com a finalidade de analisar o comportamento da muscovita com traços de íons e também para que esses íons criassem canais com o objetivo de revelar maior quantidade de traços fósseis. Realizamos planejamento utilizando algorítimo D-ótimo para realizar tratamentos térmicos com diferentes tempos e temperaturas, a fim de obter dados de ''annealing'' para a muscovita. Medimos o comprimento dos traços de íons projetados com as seguintes dependências: massa do íon, tempo de ''annealing'', temperatura de ''annealing'', energia de incidência e ângulo de incidência. Os parâmetros energia de incidência, ângulo de incidência e características do íon, não são considerados em nenhum dos modelos disponíveis na literatura. Assim sendo, formulamos um novo modelo empírico para a cinética de ''annealing'': $l = l_0 + a*energia - e^{\left(\frac{temperatura}{b + c*log(tempo)}\right)}$, $l$ sendo comprimento do traço com ''annealing'' e $l_0$ o comprimento sem ''annealing'' e, as constantes $a$, $b$ e $c$ ajustadas a partir dos dados experimentais. As constantes $a$ e $L_0$ são as variáveis relativas ao ângulo de incidência, tipo do íon e energia. Este modelo, além de ter um número menor de parâmetros, com uma simples modificação, $\frac{L}{L_0} = 1 + A.e^{\frac{T}{b}},\ b = B+C.ln(t)$, pode ser aplicado também para traços de fissão confinados. Nesse caso são apenas 3 parâmetros, $A$, $B$ e $C$ e o modelo ajustado possibilita a análise térmica em qualquer mineral que possuir dados experimentais. Neste trabalho mostramos o ajuste para os seguintes minerais: apatita, zircão, epídoto e muscovita. A partir dos traços de íons que sofreram ''annealing'' conseguimos ajustar parâmetros e obtivemos resultados consistentes com trabalhos anteriores. Um deles foi a previsão de \citeauthor{Bigazzi1967} que, possivelmente, utilizou amostras de superfície à 303K. Com esse resultado, validamos que traços de íons podem gerar bons resultados no estudo de ''annealing'' em laboratório e em tempos geológicos. Por fim, desenvolvemos um aplicativo que contempla: o ajuste dos parâmetros do modelo aos dados experimentais de modo automático, a obtenção de índices térmicos (temperatura de fechamento e zona de ''annealing parcial'') independente do mineral e a reconstrução de histórias térmicas para múltiplos minerais a partir de vínculos geológicos, da idade e de uma lista de comprimento de traços confinados. Além dessas características, a inédita ferramenta utiliza interface ''web'' que pode ser utilizada em qualquer plataforma e sistema operacional. Por fim, os resultados significativos foram: novos dados de ''annealing'' de traços de íons em mica muscovita, novo modelo empírico para abordar a cinética do ''annealing'' para traços de íons ou fissão e um aplicativo para tratamento de dados, ajuste, obtenção de índices térmicos e histórias térmicas / Abstract: In this work we studied muscovite as a thermocronometer. Muscovite have low amount of uranium, below 5 parts per million. Because of that it is impractical to be used as thermocronometer. Thus irradiating it with swift heavy ions of $ ^ {238} U $, moderated by aluminum foil (resulting in different energies) and with different angles of incidence is one way to analyze the behavior of muscovite ion tracks. These tracks can act like channels to the acid, chemical etching, revealing more fossil traces. We carry out experimental planning using D-optimal algorithm do thermal treatments at different times and temperatures in order anneal muscovite tracks. We measured the length of the ion tracks created with the following dependencies: ion mass, annealing time and temperature, impact energy and angle of incidence. The incidence of energy parameters, angle of incidence and ion characteristics are not considered in any of the models available in the literature. Therefore, we have developed a new empirical model for the kinetics of annealing: $l = l_0 + a*energia - e^{\left(\frac{temperatura}{b + c*log(tempo)}\right)}$, $l$ annealed fission track length and $l_0$ fission track length and the constants $a$, $b$ and $c$ adjusted from the experimental data . The constants $a$ and $L_0$ are related to the angle of incidence, type of ion and energy. This model, besides having fewer parameters, with a simple modification, $\frac{L}{L_0} = 1 + A.e^{\frac{T}{b}},\ b = B+C.ln(t)$ may also be applied to confined fission tracks. The adjusted model , with only 3 parameters, $A$, $B$ and $C$, enables thermal analysis in any mineral that has experimental data. We show fitting for the following minerals: apatite, zircon, epidote and muscovite. From the annealed ion tracks we fit the data to get all parameters and obtained results consistent with previous work. One was that we predict that \citeauthor{Bigazzi1967}, possibly, used surface samples with 303 K. With this result, we validate that ions tracks can generate good results using annealing laboratory data extrapolated to geological time. Finally, we developed an application with the following features: automatic model fitting to experimental data, simulation of thermal index (closure temperature and partial annealing) independent of the mineral and the reconstruction of thermal histories for multiple minerals from geological. In addition to these features, the application has web interface and can be used on any platform and operating system. Finally, the most significant results of this work were: new experimental annealing data of ion tracks in muscovite, new empirical model to increase the knowledge of the ion or fission tracks annealing kinetics and an application for data processing, fit and simulation of thermal index and thermal histories reconstruction / Mestrado / Física / Mestre em Física

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