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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.
11

Ceramic production in a Roman frontier zone : a comparative Neutron Activation and Petro-Textural analysis of Roman coarse pottery from selected sites on and around the Antonine wall, Scotland

Gillings, Mark January 2009 (has links)
A series of recent excavations on the 2nd Century AD Antonine frontier forts of the Midland Scottish valley, have produced results which suggest that the army was making its own pottery on an appreciable scale. This was at a time when pottery production was thought to have moved almost exclusively into civilian hands. The possible local ware groups identified by the excavations were largely independent of firm source indicators such as kiln and waster material and the number of available samples was often-small. A program of Neutron Activation and Thin Section petrological analyses was undertaken along with an investigation into Textural Analysis, a facet of the Petrological toolkit. The aim was both to define the site ware groups and a group of specialist vessels thought to be local to Scotland, the Mortaria, and to make statements as to their provenance. Although the Mortaria analysis was limited by problems of sample group size and availability, by improving the objectivity of the statistical handling of the derived data sets and developing methods for the high level study of textural data, the site ware groups were defined successfully at both the "intrall and "inter" site levels. The analyses also furnished interpretations as to the mode and nature of the site production schemes. Through the full analysis of' site Daub samples linked to more traditional provenancing techniques, in all but one case the ware groups could be assigned to the source sites, where contrasting production modes could be identified with military as opposed to civilian production.
12

Segmentace 3D obrazových dat s využitím pokročilých texturních a tvarových příznaků / Segmentation of 3D image data using advanced textural and shape features

Novosadová, Michaela January 2014 (has links)
This thesis first describes theory of range of methods of textural and shape analysis. In several published articles some of the mentioned methods are used for automatic detection of lesion in spine in CT images. Some of these articles are shortly presented (in this thesis). Next part of the thesis includes description of various classifiers which are used for classification of feature vectors. Practical part of the thesis is a design and implementation of image data segmentation solution (metastatic lesions in vertebrae) with use of classification of feature vectors formed by texture and shape symptoms. The thesis also deals with the selection of significant features for segmentation. Segmentation algorithm is tested on medical data.
13

Ceramic production in a Roman frontier zone: A comparative Neutron Activation and Petro-Textural analysis of Roman coarse pottery from selected sites on and around the Antonine wall, Scotland.

Gillings, Mark January 1991 (has links)
A series of recent excavations on the 2nd Century AD Antonine frontier forts of the Midland Scottish valley, have produced results which suggest that the army was making its own pottery on an appreciable scale. This was at a time when pottery production was thought to have moved almost exclusively into civilian hands. The possible local ware groups identified by the excavations were largely independent of firm source indicators such as kiln and waster material and the number of available samples was often-small. A program of Neutron Activation and Thin Section petrological analyses was undertaken along with an investigation into Textural Analysis, a facet of the Petrological toolkit. The aim was both to define the site ware groups and a group of specialist vessels thought to be local to Scotland, the Mortaria, and to make statements as to their provenance. Although the Mortaria analysis was limited by problems of sample group size and availability, by improving the objectivity of the statistical handling of the derived data sets and developing methods for the high level study of textural data, the site ware groups were defined successfully at both the "intrall and "inter" site levels. The analyses also furnished interpretations as to the mode and nature of the site production schemes. Through the full analysis of' site Daub samples linked to more traditional provenancing techniques, in all but one case the ware groups could be assigned to the source sites, where contrasting production modes could be identified with military as opposed to civilian production. / SERC
14

Targeted anti-angiogenic therapy in metastatic renal cell carcinoma and methodological improvements in assessment of therapeutic response with imaging biomarkers

Vinayan, Anup January 2018 (has links)
Background: Drugs targeting angiogenic pathway remain the mainstay of treatment for metastatic renal cell carcinoma (mRCC). Tyrosine Kinase Inhibitors (TKI) as Sunitinib, Pazopanib as single agents and humanised monoclonal antibody bevacizumab (Bev) in combination with Interferon- α2a (IFN) have established as the first-line therapy for mRCC. Despite improvements in treatment, there are multiple questions which remain unanswered. In the combination of Bev and IFN, the respective role of each drug and whether any additional anti-angiogenic activity is gained by adding IFN to Bev remains unknown. As the clinical benefit obtained with these cytostatic agents does not always correlate with the conventional response assessment techniques as RECIST, it is necessary to reconsider the methods by which we assess benefit from these therapies. In this thesis, I report three studies aiming to answer these questions. Methods: With the clinical trial reported here, I explore whether Bev induced changes in vascular parameters measured by Dynamic Contrast Enhanced MRI (DCE-MRI) is significantly enhanced by the addition of IFN. In a phase II, randomised, open labelled, multicentre trial, treatment naïve mRCC patients were randomised to receive Bev on its own or in combination with a low dose (3MU) or standard dose (9MU) IFN. DCE-MRI was used to assess the changes in vascularity with the primary endpoint being, changes in transfer coefficient (Ktrans) after six weeks of treatment. I also report two retrospective imaging-based studies, using contrast-enhanced CT scans, performed to improve the methodology of response assessment for these antiangiogenic therapeutics. Here I explore the use of a) combining changes in size and arterial phase contrast enhancement measured using CT scan and b) changes in CT texture as methods of therapeutic response assessment in mRCC patients treated with TKI. Results: With the phase 2 clinical trial, we faced significant difficulty in recruitment as a result of restrictions in access to treatment in NHS, other competing studies and restrictions proposed by the DCE-MRI inclusion criteria. With slow recruitment, an unplanned analysis was performed after 21 patients were recruited. Analysis of primary endpoint showed no trend in the difference between arms with no correlation found between change in Ktrans and addition of IFN to bevacizumab. Effect size analysis performed due to the small numbers recruited failed to show any significance in the observed difference in Ktrans. Change in Ktrans and Kep may identify a group of patients likely to have PFS > 6 months, but this observation needs to evaluation in a larger sample size. Measuring size and change in arterial phase enhancement retrospectively using CT, a new criterion "modified" Choi, which prerequisite a combination of a decrease in arterial phase density by 15% and a decrease in size by 10% for response was proposed. Response assessment was measured with RECIST, Choi and modified Choi individually in 20 evaluable patients retrospectively and clinical benefit compared with Kaplan-Meier statistics and Log-Rank test. Response assessment as defined by the modified Choi criteria successfully identified patients who received clinical benefit from the treatment. Time to progression (TTP) was 448 days for the partial response and 89 days for stable disease as per the new criteria which were statistically significant with a p-value of 0.002. The second retrospective analysis explored the textural changes in enhanced CT scan. Performed in collaboration with researchers from Brighton University who developed the software algorithm used to assess changes in entropy and uniformity, 87 metastases from 39 patients with mRCC were analysed at baseline and after two cycles of TKI treatment. Textural parameters and response assessment criteria were correlated with TTP. After two cycles of TKI, the decrease in tumour entropy was 3%-45%, and increase in uniformity was 5%-21%. At a threshold change of -2% with uniformity, on a coarse scale of 2.5, the textural change was able to separate responders from non-responders. With Kaplan-Meier analysis comparing all four criteria, the percentage change in uniformity was statistically more significant than for RECIST, Choi, and Modified Choi criteria. Cox regression analysis showed that texture uniformity was an independent predictor of time to progression. Discussion: With the studies reported here, I was able to demonstrate the importance of improving the methodology in assessment of therapeutic response to targeted anti-angiogenic therapy in metastatic renal cell carcinoma. Even though the clinical trial, terminated early due to slow recruitment, did not reach its primary endpoint, changes in other vascular parameters as Kep combined with changes Ktrans showed tendency towards identifying a group of patients who derived clinical benefit of >6months with these therapies. This is particularly exciting as given the vascular stabilisation effect proposed for bevacizumab, the effusion parameter Kep may be a better tool in assessing response rather than Ktrans and warrants further assessment in a larger cohort. Modified choi criterion and textural analysis are two important methodological improvements in response assessment of cytostatic anti-angiogenic therapy. In the analyses reported here, both techniques have shown superiority over RECIST in response assessment and differentiating mRCC patients who is likely to gain clinical benefit by TKI therapy. Validation of these criteria on a larger patient cohort is important. As these criterions are assessed on standard enhanced CT scans, incorporating these criteria, especially modified choi criterion, as part of standard CT assessment could be performed and will provide a real world validation. Retrospective assessment using larger cohort of patients from previous phase 3 trials or inclusion of these parameters prospectively in phase 3 trials would also help us in evaluating these modalities further.
15

Diagnóstico da fertilidade do solo e estimativas de recomendação de calagem e adubação NPK para o Mato Grosso do Sul / Diagnosis of soil fertility and estimated recommendation of lime and NPK fertilization for the Mato Grosso do Sul

Lins, Caio Buainain 19 July 2012 (has links)
Made available in DSpace on 2015-03-26T13:53:25Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1310091 bytes, checksum: 1903711904b447b1c04152b648bb8a7e (MD5) Previous issue date: 2012-07-19 / The diagnosis of soil fertility, when performed based on soil analysis results of a certain State of the Federation, can serve as an instrument to assist in the planning and definition of public policies related to the productive sector of the State. The work had as objectives: diagnosing soil fertility of Mato Grosso do Sul (MS); establish relationships between some attributes of soils studied; compare the recommendations of liming and fertilizing obtained by different technical bulletins of recommendation used in MS, to its main agricultural crops, with the data acquisition (NPK) or production (calcareous) in the State of MATO GROSSO DO SUL in 2010. In this work it were used chemicals and physicals results database of soil State of MS. This database, was obtained with a soil analysis laboratory that operates in the State of MATO GROSSO DO SUL, is referring to the results of analyses of 8,125 samples collected in layers of 0 to 20 cm in the year 2010. All samples were analyzed chemically, by establishing: pH (CaCl2); P (Mehlich-1); K (Mehlich-1); Ca2 +; Mg2 +; Al3 +; (H + Al) and organic matter (M.O.). Were calculated the sum of the bases (SB), base saturation (V) and CTC at pH 7 (T). Textural and P-resin (P-Res) analyses were performed at 1,813 and 907 samples, respectively. Soil fertility diagnosis of MS was performed by descriptive statistics: frequency, median, standard deviation, amplitude and the mean of the attributes of the soil in the State. Were evaluated the relationship between the meaning of P (Mehlich-1) with P-Res and clay; the meaning of M.O. with T and V with pH (CaCl2). Were compared the quantities of calcareous produced and the total of NPK consumed in the State with the estimated recommendation of lime and NPK for the main crops of the State (pasture, soy, corn, sugar cane and eucalyptus). Lime recommendations , were determined by the method of saturation by bases, and the estimated fertilization were carried out on the basis of: percentages frequency of soil fertility classes, the area (ha) of a crop and by technical bulletins of recommendation used in MS.1) as regards the diagnosis of fertility: 21.74% of samples have pH in CaCl2 less than or equal to 4.8; 82.18% of samples have aluminum meaning less than or equal to 0.2 cmolc dm-3; 7.35% of the samples have bases saturation less than or equal to 35%; 46.16% phosphorus samples were below the critical level for annual crops; 12.53% potassium samples are below critical levels for annual crops; 10.72% of calcium + magnesium samples were below the critical level for annual crops. 2) the production of calcareous in MS was insufficient to State consumption in 2010. 3) N is the nutrient used in smaller quantities in relation to the recommendations, followed by P. 4) the quantities of K2O used in MS in 2010 were close to those recommended. 5) The relationships obtained in the form of equations, between soil attributes are useful to support pedotransfer functions. / O diagnóstico da fertilidade dos solos, quando realizado baseado em resultados de análises de solos de um determinado Estado da Federação, poderá servir de instrumento para auxiliar no planejamento e definição das políticas públicas ligadas ao setor produtivo daquele Estado. O trabalho teve como objetivos: diagnosticar a fertilidade dos solos do Mato Grosso do Sul (MS); estabelecer relações entre alguns atributos dos solos estudados; comparar as recomendações de calagem e adubação obtidas por meio de diferentes manuais de recomendações de corretivos e fertilizantes utilizados na região, para suas principais culturas agrícolas, com os dados de aquisição (NPK) ou produção (calcários) no Estado do MS em 2010. Foi realizado o levantamento das características químicas e da granulometria dos solos, utilizando-se banco de dados de resultados analíticos referentes aos solos do Estado do MS. O banco de dados, pertencente a um laboratório de análise de solo que atua no Estado do MS, é referente aos resultados de análises de 8.125 amostras coletadas nas camadas de 0 a 20 cm, no ano de 2010. Todas as amostras foram analisadas quimicamente, determinando-se: pH (CaCl2); P (Mehlich-1); K (Mehlich-1); Ca2+; Mg2+; Al3+; (H+Al) e matéria orgânica (M.O.). Foram calculadas a soma de bases (SB), saturação por bases (V) e CTC a pH 7 (T). Foram realizadas análises texturais e de P-Resina (P-Res) em 1.813 e 907 amostras, respectivamente. O diagnóstico da fertilidade dos solos do MS foi realizado por meio de estatísticas descritivas: frequência, mediana, desvio padrão, amplitude e a média dos atributos do solo no Estado. Foram avaliadas as relações entre o teor de P (Mehlich-1) com teor de P-res e argila; teor de M.O. com T e V com pH (CaCl2). Foram comparadas as quantidades de calcário produzidas e o total de fertilizantes NPK consumidos no Estado com as necessidades de calagem e de fertilização com NPK para as principais culturas do Estado (pastagem, soja, milho, cana-de-açúcar e eucalipto). As recomendações de calagem, determinadas pelo método de saturação por bases, e adubação foram realizadas com base nas: porcentagens de frequência das classes de fertilidade do solo, da área (ha) de ocupação das culturas e pelos principais boletins técnicos de recomendação utilizados no MS. 1) Quanto ao diagnóstico da fertilidade: 21,74 % das amostras têm pH em CaCl2 menor ou igual a 4,8; 82,18 % das amostras apresentam teor de alumínio menor ou igual a 0,2 cmolc dm-3; 7,35 % das amostras têm saturação por bases menor ou igual a 35 %; 46,16 % das amostras de fósforo apresentaram-se abaixo do nível crítico para culturas anuais; 12,53 % das amostras de potássio estão abaixo dos níveis críticos para culturas anuais;10,72 % das amostras de cálcio + magnésio apresentaram-se abaixo do nível crítico para culturas anuais. 2) A produção de calcário no MS foi insuficiente ao consumo do Estado em 2010. 3) O N é o nutriente utilizado em menor quantidade em relação as recomendações, seguido do P. 4) As quantidades de K2O utilizadas no MS em 2010 foram próximas às recomendadas. 5) Os relacionamentos obtidos, na forma de equações, entre atributos do solo são úteis para embasar funções de pedotransferência.
16

AnÃlise integrada dos aspectos geoambientais e da dinÃmica costeira de mÃdio e curto perÃodo da planÃcie litorÃnea entre as Praias do Futuro e Porto das Dunas, CearÃ, Brasil / Analyzes the geo-environmental aspects in an integrated manner and the coastal dynamics of short to medium duration of the coastal plain between the Porto das Dunas Beach and Praia do Futuro Beach, Cearà State, Brazil

Marcia Thelma Rios Donato Marino 05 May 2014 (has links)
Universidade de Fortaleza / CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / Esta pesquisa analisa de forma integrada os aspectos geoambientais e a dinÃmica costeira de curto e mÃdio perÃodo da planÃcie litorÃnea entre as praias do Futuro e Porto das Dunas, litoral leste do CearÃ, embasada na anÃlise multitemporal da variaÃÃo da linha de costa e mudanÃas morfolÃgicas. Aplicou-se o geoprocessamento conciliado Ãs caracterÃsticas geoambientais, morfodinÃmicas, hidrodinÃmicas, aos processos eÃlicos, Ãs aÃÃes antrÃpicas e à avaliaÃÃo dos Ãndices de vulnerabilidade à erosÃo. A Ãrea perfaz 15 km de litoral representada pelos Setores: 1 - Praia Porto das Dunas; 2 - AbreulÃndia (COFECO) e Sabiaguaba; e 3 - CaÃa e Pesca e Praia do Futuro, alÃm das desembocaduras dos rios Pacoti e CocÃ. Os aspectos metodolÃgicos foram pautados em atividades de gabinete, campo, laboratÃrio e anÃlise integrada dos dados. Elaborou-se um monitoramento sazonal durante um ano (08/10 a 08/11). Geologicamente, a Ãrea està representada por dois domÃnios geolÃgicos: unidade basal e planÃcie costeira, ambas influenciam na dinÃmica costeira das praias monitoradas, associadas Ãs condiÃÃes climÃticas. O clima à tropical chuvoso, semiÃrido e apresenta forte irregularidade pluviomÃtrica anual, com duas estaÃÃes distintas, uma seca e prolongada e outra com precipitaÃÃes curtas. Os dados modais de ondas revelam o predomÃnio do tipo deslizante, praias com relevos suaves e baixas declividades. A altura das ondas na zona de arrebentaÃÃo apresentou valor mÃdio de 1,1m, variando de 0,9m a 1,2m. Os perÃodos de ondas assumiram um padrÃo sazonal, menores na estaÃÃo seca e maiores na chuvosa, mÃximo de 15,9s e mÃnimo 6,1s. O estÃgio morfodinÃmico do Setor 1 à dissipativo, no Setor 2 varia de dissipativo a intermediÃrio e, por vezes, refletivo, e no Setor 3 predomina estÃgios intermediÃrios a dissipativos com as maiores extensÃes dos perfis praiais. O balanÃo sedimentar confirma um estado que busca o equilÃbrio entre os processos deposicional e erosional, entretanto com tendÃncia erosional para os Setores 1 e 2, e deposicional para o Setor 3, corroborando com os volumes dos sedimentos e com a variaÃÃo da linha de costa. As taxas de avanÃo e recuo da linha de costa foram obtidas utilizando-se a extensÃo Digital Shoreline Analysis System para o software ArcGIS 10.0, integrando dados georreferenciados, entre os anos de 1972 e 2010. Da praia Porto das Dunas atà a margem esquerda do rio Pacoti, definiu-se um estÃgio erosivo, taxa de variaÃÃo mÃdia de -3,53m/ano e -17,67m em 5 anos; entre a foz do rio Pacoti e a praia da AbreulÃndia, observaram-se Ãndices de erosÃo mÃdia de -0,31m/a e -2,18m em 7 anos; a praia da AbreulÃndia atà a desembocadura do rio Cocà apresentou tendÃncia erosional mÃdia de -0,07m/ano e -2,59m, em 38 anos, caracterizando uma estabilidade nesse setor, provavelmente, devido ao cordÃo descontÃnuo de rochas de praia paralelo à costa; a Praia do Futuro apresenta uma tendÃncia fortemente progradante, mÃdia de +1,43m/ano e +54,33m, em 38 anos. A anÃlise da variaÃÃo textural dos sedimentos de praia constatou o predomÃnio da fraÃÃo arenosa ao longo dos 15 km de praias, predominando areia mÃdia, moderadamente selecionada, com fraÃÃes mais finas nas praias do extremo NW e as mais grossas nas porÃÃes centrais. As caracterÃsticas granulomÃtricas sÃo fortemente condicionadas pela influÃncia dos agentes hidrodinÃmicos, eÃlicos e meteorolÃgicos, associados ao tipo, orientaÃÃo e localizaÃÃo da praia e a proximidade e tipo da Ãrea fonte de sedimentos. Os perfis morfodinÃmicos praiais estÃo associados à sazonalidade meteorolÃgica, perfis de inverno nos perÃodos de transiÃÃo e estiagem, e de verÃo no perÃodo chuvoso. A distribuiÃÃo dos sedimentos ao longo dos perfis registra para o perÃodo chuvoso a predominÃncia dos mais grossos nas Ãreas mais afastadas da linha de costa e mais finos na regiÃo subaquosa, ocorrendo uma inversÃo no perÃodo de estiagem. TrÃs fatos sÃo destacados para as velocidades dos ventos: desenvolvimento de um gradiente vertical ascendente, certa conformidade de comportamento das curvas traÃadas em alturas diferenciadas e maiores velocidades na zona de pÃs-praia. Os rios Pacoti e Cocà apresentaram estreitamento da foz e erosÃo nas faixas praiais adjacentes; nas desembocaduras observou-se uma relaÃÃo diretamente proporcional entre a faixa praial e os depÃsitos submersos, sugerindo que esses depÃsitos funcionam como suprimento de sedimentos para a faixa praial. Todos os fatores analisados condicionaram à evoluÃÃo do litoral e foram relevantes para avaliar o grau de vulnerabilidade à erosÃo costeira, inferindo-se um grau muito alto para o Setor 1, alto a baixo para o Setor 2 e baixo a moderado para o 3, relacionado Ãs feiÃÃes e tipos de uso. O processo de urbanizaÃÃo està bastante acelerado e ocorre de forma desorganizada, sem levar em consideraÃÃo as caracterÃsticas e fragilidades dos ecossistemas, como a ocupaÃÃo das zonas de by-pass, fato que influencia diretamente na sazonalidade natural de remoÃÃo e deposiÃÃo de sedimentos arenosos, resultando no recuo da linha de costa, em razÃo da reduÃÃo do aporte de sedimentos. Recomendam-se uma fiscalizaÃÃo mais rigorosa e a implantaÃÃo de programas de monitoramento e ordenamento territorial nessa Ãrea, importantes ao equilÃbrio dinÃmico costeiro e à preservaÃÃo de Ãcones da beleza cÃnica do litoral. / This research analyzes the geo-environmental aspects in an integrated manner and the coastal dynamics of short to medium duration of the coastal plain between the Porto das Dunas Beach and Praia do Futuro Beach, East coast of Cearà state. It is based on multitemporal analysis of shoreline variation and morphological changes. This work applied the geoprocessing reconciled to geoenvironmental characteristics, morphodynamics, hydrodynamics, aeolian processes, anthropogenic actions and assessment indices of vulnerability to erosion. The area of investigation stretches 15 km of coastline represented by 3 sectors: 1-Porto das Dunas Beach; 2-AbreulÃndia (COFECO) Beach and Sabiaguaba Beach; and 3- CaÃa e Pesca Beach and Praia do Futuro Beach, in addition to the mouths of the Pacoti River and Cocà River. Methodologically, it wasguided by activities of staff, field, laboratory and integrated analysis of the data. Seasonal monitoring was elaborated during a year (08/10 to 08/11). Geologically the area is comprised of two geological domains: basal unit and the coastal plain, both of which influence the coastal dynamics of the beaches of interest-more specifically, those related to weather conditions. The climate is rainy and tropical, semi-arid, and features strong annual rainfall irregularity that characterize two distinct seasons: one with prolonged drought and another with short rainfall. The data wave modal reveal the predominance of sliding type, beaches with soft and low reliefs declivities. The height of the waves in the surf zone presented average value of 1,1m, ranging from 0,9 m to 1,2m. The wave periods follow a seasonal pattern, with smaller waves in the dry season and larger ones in rainy season (maximum of 15,9s and minimum of 6,1s). The morphodynamic stage is dissipative in Sector 1, in Sector 2 ranges from dissipative to intermediary and, sometimes, reflective. In Sector 3 it predominates the dissipative to intermediary stages with the largest extensions of beach profiles. The sedimentary balance confirms a state seeking a balance between depositional and erosional processes, however with erosional trend for Sectors 1 and 2, and depositional trend for Sector 3. This corroborates with the sediment volumes and with the coastline variation. The rates of advance and retreat of the shoreline were obtained using the Digital Shoreline Analysis System, software for ArcGIS 10.0, integrating georeferenced data, between 1972 and 2010. From Porto das Dunas Beach to the left margin of Pacoti River it was set up an erosion stage on an average of â 3,53m/year and -17.65m in 5 years. Between the mouth of the Pacoti River and AbreulÃndia Beach erosion rates were observed, average of -0,31m/year and -2.18m in a period of 7 years. The area from AbreulÃndia Beach to the mouth of the Cocà River showed erosional average of -0.07m/year, -2,59m in a period of 38 years. This evidences stability in this sector, probably due to discontinuous cord beachrocks parallel to the coast. Praia do Futuro Beach has a strong progradational average of +1.43m/year, +54.33m in a period of 38 years. The analysis of textural variation of beach sediments noted the predominance of the sandy fraction over the 15 km of beaches with medium sand, moderately selected, with finer fractions on the beaches of the far NW and the thicker on the central portions. The grain size characteristics of this coastline is strongly conditioned by the influence of hydrodynamic, wind, and weather agents, associated with the type, orientation, and location of the beach as well as the proximity and type of sediment source area. The beach morphodynamic profiles are associated with weather seasonality, winter profiles during periods of transition and drought. Moreover, summer profiles are observed in the rainy season. The distribution of sediments along the profiles was recorded in the rainy season showing a predominance of coarse in the outlying areas of the coastline and the finest in subaqueous region. In the dry season the effect is inverse. Three facts are highlighted for the speeds of the winds: development of a vertical upward gradient, certain conformity of behavior of curves drawn in different heights, and speeds in the backshore zone. The Pacoti River and the Cocà River showed narrowing in the mouth and erosion on adjacent beach tracks. Furthermore, it was observed in the mouths a relationship directly proportional between the beach range and the underwater deposits, suggesting that these deposits act as sediment suppliers to the beach range. The factors analyzed have led to the evolution of the coast and were relevant to assessing the degree of vulnerability to coastal erosion. Resulting from this process was a very high degree to the Sector 1, high to low degree to the Sector 2 and low to medium degree to the Sector 3, related to the features and types of use. The urbanization process taking place in the area is accelerated and unplanned. For example, it does not take into consideration the characteristics and weaknesses of ecosystems, such as the occupation of the by-pass areas. This latter has a direct influence on natural seasonality of removal and deposition of sandy sediments, resulting in the indentation of the coastline, due to the reduction in the contribution of sediments. Stricter supervision is recommended, and implementation of a monitoring programme and a spatial planning programme in this area are essential for the coastal dynamic balance.
17

Diversité structurale des forêts denses humides de la Province Nord de Nouvelle Calédonie : de l'arbre au paysage / Structural diversity of rainforests of North Province of New Caledonia : from tree to landscape

Blanchard, Elodie 20 December 2016 (has links)
Dans un contexte de changements globaux, il est primordial de mettre au point des pratiques de gestion durable des forêts tropicales assurant le maintien de services environnementaux clés (e.g., biodiversité, stockage de carbone) et la production de biens essentiels aux communautés locales. La mesure, la spatialisation et la compréhension des déterminismes de la structure des forêts tropicales est un challenge pour la gestion durable des ressources forestières. Les forêts denses humides (FDH) de Nouvelle-Calédonie, un point chaud de biodiversité localisé dans le Pacifique Sud-Ouest, sont un modèle d'étude idéal pour comprendre les déterminants de la structure des FDH. En effet, les FDH néo-calédoniennes sont réparties le long d’une chaîne de montagne et sont ainsi soumises à de forts gradients environnementaux auxquels se superposent différents gradients de perturbations naturelles ou anthropiques. Les objectifs de cette thèse sont (i) de définir les caractéristiques structurales des FDH néo-calédoniennes, (ii) de cartographier les FDH et prédire leur structure à large échelle, et (iii) de quantifier l'influence de l’environnement et des dynamiques forestières sur la structure des FDH. Pour cela, 23 parcelles d’inventaire forestier de 100 m x 100 m ont été mise en place en Province Nord, entre 250 et 900 m d'altitude et 1500 et 3000 mm de précipitations annuelles. En plus de caractériser localement la structure des FDH, ces parcelles ont permis de calibrer un modèle prédictif basé sur l’analyse de la texture de la canopée, à l'aide la méthode FOTO (FOurier transform Textural Ordination), qui a été appliqué à huit images satellitaires à très haute résolution Pléiades (couvrant 1295 km2). Un tel modèle capable de lier texture et structure repose sur le postulat que la relation allométrique entre le DBH (Diameter at Breast Height) et l'aire de la couronne des arbres de canopée est stable. Nous avons également testé cette relation à échelle pantropicale. Nos résultats ont montré que les FDH néo-calédoniennes sont denses (1182 ± 233 tiges/ha), ont une aire basale élevée (44 ± 11 m2/ha), une canopée relativement basse (14 ± 3 m) et une biomasse aérienne caractéristique des forêts tropicales (299 ± 83 t/ha). Elles se distinguent également par une importante variabilité structurale. Cette variabilité est du même ordre que ce soit le long de gradients environnementaux ou de gradients de succession forestière. La méthode FOTO appliquée aux images Pléiades a permis de prédire et de spatialiser des paramètres structuraux clefs (tels que la densité de tiges et la biomasse aérienne des FDH) à partir de corrélations robustes avec les indices de texture de la canopée (R² ≥ 0,6; RMSE ≤ 20%). La structure des FDH est principalement dirigée par l'insolation potentielle et l'altitude à l'échelle des massifs montagneux, et par la pente et un indicateur topographique d'humidité à l'échelle du versant. Ces travaux permettront d'estimer les ressources forestières à l'échelle de la Nouvelle-Calédonie et de définir une nouvelle typologie des FDH sur le territoire intégrant leur variabilité structurale. / In the course of global change, new practices of sustainable management in tropical rainforests that maintain key environmental services (e.g., biodiversity, carbon sequestration) and produce goods on which local communities rely is needed. The measurement, spatialization and understanding of the drivers of rainforest structure at large scale is challenging for managing sustainably forest resources. Rainforests of New Caledonia, a biodiversity hotspot located in the South-West Pacific, are a well-suited study model to explore the drivers of rainforest structure. Indeed, New Caledonian rainforests are distributed along a mountain chain, which creates strong environmental gradients overlaid by a range of natural and anthropogenic disturbance gradients. The aims of this thesis are (i) to define some structural features of New Caledonian rainforests, (ii) to map rainforests and to predict their structure at large scale, and (iii) to quantify the influence of the environment and the forest dynamics on rainforest structure. To this end, 23 one hectare forest inventories were set up in the North Province of New Caledonia. In these plots, elevation ranged between 250 and 900 m and annual rainfall between 1500 and 3000 mm. In addition to characterize locally rainforest structure, these plots were used to calibrate a predictive model based on a textural analysis of the canopy, using the FOTO (FOurier transform Textural Ordination) method, which was applied to eight very high resolution images from a Pléiades satellite (covering 1295 km2). Such a model able to relate texture and structure is based on the hypothesis that the allometric relationship between the DBH (Diameter at Breast Height) and the crown size of a canopy tree is stable. We tested this hypothesis tropics-wide. Our results show that New Caledonian rainforests are dense (1182 ± 233 tree/ha), with a high basal area (44 ± 11 m2/ha), a relatively low canopy (14 ± 3 m) and an above-ground biomass typical of tropical rainforests (299 ± 83 t/ha). These forests are also characterized by a high structural variability. This variability has the same range when influenced by environmental gradients as when influenced by forest succession gradients. The FOTO method applied to Pléiades images allowed to predict and spatialize key structural parameters (like the stem density or the above-ground biomass of rainforests) from robust correlations with the textural indices of the canopy (R² ≥ 0,6; RMSE ≤ 20%). The structure of New Caledonian rainforest is mainly driven by the potential insolation and the elevation at the scale of mountain massifs, and by the slope and the topographic wetness at the scale of a mountainside. These findings will enable to estimate rainforest resources across the territory and to define a new typology of New Caledonian rainforests taking into account their structural variability.
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Matematický model trajektorie svazku nervových vláken pro účely diagnostiky glaukomu / Mathematical model of retinal nerve fiber bundle trajectory for diagnosis of glaucoma

Sedláček, Miloš January 2012 (has links)
This work deals with mathematical description of nerve fiber bundle trajectories for the diagnosis of glaucoma. Also gives a brief explanation in the principle of fundus camera and glaucoma. Its aim is to implement the model into MATLAB software, to project a~methodics of its use and also to realize it.
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Spectral and textural analysis of high resolution data for the automatic detection of grape vine diseases / Analyses spectrale et texturale de données haute résolution pour la détection automatique des maladies de la vigne

Al saddik, Hania 04 July 2019 (has links)
La Flavescence dorée est une maladie contagieuse et incurable de la vigne détectable sur les feuilles. Le projet DAMAV (Détection Automatique des MAladies de la Vigne) a été mis en place, avec pour objectif de développer une solution de détection automatisée des maladies de la vigne à l’aide d’un micro-drone. Cet outil doit permettre la recherche des foyers potentiels de la Flavescence dorée, puis plus généralement de toute maladie détectable sur le feuillage à l’aide d’un outil multispectral dédié haute résolution.Dans le cadre de ce projet, cette thèse a pour objectif de participer à la conception et à l’implémentation du système d’acquisition multispectral et de développer les algorithmes de prétraitement d’images basés sur les caractéristiques spectrales et texturales les plus pertinentes reliées à la Flavescence dorée.Plusieurs variétés de vigne ont été considérées telles que des variétés rouges et blanches; de plus, d’autres maladies que ‘Flavescence dorée’ (FD) telles que Esca et ‘Bois noir’ (BN) ont également été testées dans des conditions de production réelles. Le travail de doctorat a été essentiellement réalisé au niveau feuille et a impliqué une étape d’acquisition suivie d’une étape d’analyse des données.La plupart des techniques d'imagerie, même multispectrales, utilisées pour détecter les maladies dans les grandes cultures ou les vignobles, opèrent dans le domaine du visible. Dans DAMAV, il est conseillé que la maladie soit détectée le plus tôt possible. Des informations spectrales sont nécessaires, notamment dans l’infrarouge. Les réflectances des feuilles des plantes peuvent être obtenues sur les longueurs d'onde les plus courtes aux plus longues. Ces réflectances sont intimement liées aux composants internes des feuilles. Cela signifie que la présence d'une maladie peut modifier la structure interne des feuilles et donc altérer sa signature.Un spectromètre a été utilisé sur le terrain pour caractériser les signatures spectrales des feuilles à différents stades de croissance. Afin de déterminer les réflectances optimales pour la détection des maladies (FD, Esca, BN), une nouvelle méthodologie de conception d'indices de maladies basée sur deux techniques de réduction de dimensions, associées à un classifieur, a été mise en place. La première technique de sélection de variables utilise les Algorithmes Génétiques (GA) et la seconde s'appuie sur l'Algorithme de Projections Successives (SPA). Les nouveaux indices de maladies résultants surpassent les indices de végétation traditionnels et GA était en général meilleur que SPA. Les variables finalement choisies peuvent ainsi être mises en oeuvre en tant que filtres dans le capteur MS.Les informations de réflectance étaient satisfaisantes pour la recherche d’infections (plus que 90% de précision pour la meilleure méthode) mais n’étaient pas suffisantes. Ainsi, les images acquises par l’appareil MS peuvent être ensuite traitées par des techniques bas-niveau basées sur le calcul de paramètres de texture puis injectés dans un classifieur. Plusieurs techniques de traitement de texture ont été testées mais uniquement sur des images couleur. Une nouvelle méthode combinant plusieurs paramètres texturaux a été élaborée pour en choisir les meilleurs. Nous avons constaté que les informations texturales pouvaient constituer un moyen complémentaire non seulement pour différencier les feuilles de vigne saines des feuilles infectées (plus que 85% de précision), mais également pour classer le degré d’infestation des maladies (plus que 74% de précision) et pour distinguer entre les maladies (plus que 75% de précision). Ceci conforte l’hypothèse qu’une caméra multispectrale permet la détection et l’identification de maladies de la vigne en plein champ. / ‘Flavescence dorée’ is a contagious and incurable disease present on the vine leaves. The DAMAV project (Automatic detection of Vine Diseases) aims to develop a solution for automated detection of vine diseases using a micro-drone. The goal is to offer a turnkey solution for wine growers. This tool will allow the search for potential foci, and then more generally any type of detectable vine disease on the foliage. To enable this diagnosis, the foliage is proposed to be studied using a dedicated high-resolution multispectral camera.The objective of this PhD-thesis in the context of DAMAV is to participate in the design and implementation of a Multi-Spectral (MS) image acquisition system and to develop the image pre-processing algorithms, based on the most relevant spectral and textural characteristics related to ‘Flavescence dorée’.Several grapevine varieties were considered such as red-berried and white-berried ones; furthermore, other diseases than ‘Flavescence dorée’ (FD) such as Esca and ‘Bois noir’ (BN) were also tested under real production conditions. The PhD work was basically performed at a leaf-level scale and involved an acquisition step followed by a data analysis step.Most imaging techniques, even MS, used to detect diseases in field crops or vineyards, operate in the visible electromagnetic radiation range. In DAMAV, it is advised to detect the disease as early as possible. It is therefore necessary to investigate broader information in particular in the infra-red. Reflectance responses of plants leaves can be obtained from short to long wavelengths. These reflectance signatures describe the internal constituents of leaves. This means that the presence of a disease can modify the internal structure of the leaves and hence cause an alteration of its reflectance signature.A spectrometer is used in our study to characterize reflectance responses of leaves in the field. Several samples at different growth stages were used for the tests. To define optimal reflectance features for grapevine disease detection (FD, Esca, BN), a new methodology that designs spectral disease indices based on two dimension reduction techniques, coupled with a classifier, has been developed. The first feature selection technique uses the Genetic Algorithms (GA) and the second one relies on the Successive Projection Algorithm (SPA). The new resulting spectral disease indices outperformed traditional vegetation indices and GA performed in general better than SPA. The features finally chosen can thus be implemented as filters in the MS sensor.In general, the reflectance information was satisfying for finding infections (higher than 90% of accuracy for the best method) but wasn’t enough. Thus, the images acquired with the developed MS device can further be pre-processed by low level techniques based on the calculation of texture parameters injected into a classifier. Several texture processing techniques have been tested but only on colored images. A method that combines many texture features is elaborated, allowing to choose the best ones. We found that the combination of optimal textural information could provide a complementary mean for not only differentiating healthy from infected grapevine leaves (higher than 85% of accuracy), but also for grading the disease severity stages (higher than 73% of accuracy) and for discriminating among diseases (higher than 72% of accuracy). This is in accordance with the hypothesis that a multispectral camera can enable detection and identification of diseases in grapevine fields.
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Écologie alimentaire et paléoenvironnements des cervidés européens du Pléistocène inférieur : le message des textures de micro-usure dentaire / Feeding ecology and paleoenvironments of ancient cervids from the early Pleistocene of Europe : the message of the dental microwear textures

Berlioz, Emilie 05 December 2017 (has links)
Le refroidissement global et les oscillations entre cycles glaciaires et interglaciaires du Pléistocène inférieur ont pour conséquence une alternance entre milieux steppiques et forestiers, favorisant par là-même renouvellements et dispersions fauniques dont celui du genre Homo.Dans les interprétations paléoenvironnementales basées sur les assemblages fauniques, les cervidés, parmi les plus abondants mammifères, sont classiquement considérés comme forestiers, mais ce paradigme ne reflète pas la complexité de la diversité écologique réelle des cervidés.L'analyse texturale de 921 spécimens représentant les 5 cervidés actuels à l'écologie référencée a permis d'établir une robuste base de données et d'attester du lien significatif entre micro-usure dentaire et ressources végétales. L'analyse de 547 cervidés fossiles issus de 15 localités européennes souligne leur grande diversité écologique. Eucladoceros ctenoides et Metacervoceros rhenanus présentent une alimentation plastique. Leur analyse permet l'identification de réponses alimentaires adaptatives aux modifications environnementales liées aux oscillations climatiques. Ces deux cervidés, eurytopiques, constituent des indicateurs écologiques incontournables. La composante forestière supportée par la présence des cervidés est ici remise en cause ; les cervidés étant plus diversifiés écologiquement. L'analyse de la texture de la micro-usure dentaire des cervidés présents dans des sites européens, où la présence du genre Homo a été avancée, vise à identifier le type potentiel d'habitat favorable à sa dispersion en Eurasie. / The early Pleistocene is a period of global cooling and climatic oscillations punctuated by glacial and interglacial cycles. This period of climatic instability leads to an alternation of steppe and forest habitats resulting in faunal renewals and dispersals, including Homo dispersal.In paleoenvironmental reconstructions based on faunal assemblages, deer, which are among the most abundant mammals, are traditionally considered forest dwellers. However, this paradigm is far from reflecting the real complexity of deer ecological diversity.Via the textural analysis of 921 representatives of the 5 extant European deer with known ecology, a solid reference database has been setup. It attests of the significative link existing between dental micro-wear and vegetal resources. The analysis of 547 fossils from 15 European localities underlines the ecological diversity among fossil deer. Eucladoceros ctenoides and Metacervoceros rhenanus are plastic in their diet. The analysis of such deer allows the identification of dietary adaptive answers to environmental modifications resulting from climatic oscillations. Being eurytopic, they constitute essential proxies for paleoenvironmental reconstructions. The results challenge the link existing between the occurrence of deer and the presence of forest habitats, as deer are ecologically more diversified.The textural analysis of deer from European human bearing localities aims at characterizing potential habitats favorable toward Homo dispersion in Eurasia.

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