923 resultados para classification aided by clustering


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Pós-graduação em Educação - FFC

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The aim of this work is to discriminate vegetation classes throught remote sensing images from the satellite CBERS-2, related to winter and summer seasons in the Campos Gerais region Paraná State, Brazil. The vegetation cover of the region presents different kinds of vegetations: summer and winter cultures, reforestation areas, natural areas and pasture. Supervised classification techniques like Maximum Likelihood Classifier (MLC) and Decision Tree were evaluated, considering a set of attributes from images, composed by bands of the CCD sensor (1, 2, 3, 4), vegetation indices (CTVI, DVI, GEMI, NDVI, SR, SAVI, TVI), mixture models (soil, shadow, vegetation) and the two first main components. The evaluation of the classifications accuracy was made using the classification error matrix and the kappa coefficient. It was defined a high discriminatory level during the classes definition, in order to allow separation of different kinds of winter and summer crops. The classification accuracy by decision tree was 94.5% and the kappa coefficient was 0.9389 for the scene 157/128. For the scene 158/127, the values were 88% and 0.8667, respectively. The classification accuracy by MLC was 84.86% and the kappa coefficient was 0.8099 for the scene 157/128. For the scene 158/127, the values were 77.90% and 0.7476, respectively. The results showed a better performance of the Decision Tree classifier than MLC, especially to the classes related to cultivated crops, indicating the use of the Decision Tree classifier to the vegetation cover mapping including different kinds of crops.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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This exploratory and descriptive study described sociodemographic and health variables of caregivers of elderly people with Alzheimer's disease, associating care provided with resilience. Participants were 101 caregivers over 18 years old who accompanied older adults in a Primary Care Unit of a Brazilian public hospital in 2009. Questionnaires regarding the profile, the Beck Depression Inventory, and the Resilience Scale were used. Descriptive statistical analysis was performed. Most caregivers were female, without depression, aided by other people in providing care, and had a high degree of resilience. The variables degree of kinship, medical treatment, the use of medication, tiredness, prostration, discouragement, and caregivers' mental health had significant association with resilience. Physical health was significantly associated to experience in care, with 82 elderly people presenting acute cognitive damage. Older adults in the family context can benefit from a more resilient caregiver.

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Monitorar a condição de uso de toda a extensão das rodovias brasileiras é tarefa dispendiosa e demorada. Este trabalho trata de novas técnicas que permitem o levantamento da condição da superfície dos pavimentos rodoviários de forma ágil utilizando imagens hiperespectrais de sensor digital aeroembarcado. Nos últimos anos, um número crescente de imagens de alta resolução espacial tem surgido no mercado mundial com o aparecimento dos novos satélites e sensores aeroembarcados de sensoriamento remoto. Propõe-se uma metodologia para identificação dos pavimentos asfálticos e classificação das principais ocorrências dos defeitos na superfície do pavimento. A primeira etapa da metodologia é a identificação da superfície asfáltica na imagem, utilizando uma classificação híbrida baseada inicialmente em pixel e depois refinada por objetos. A segunda etapa da metodologia é a identificação e classificação das ocorrências dos principais defeitos nos pavimentos flexíveis que são observáveis nas imagens de alta resolução espacial. Esta última etapa faz uso intensivo das novas técnicas de classificação de imagens baseadas em objetos. O resultado final é a geração de índices da condição da superfície do pavimento a partir das imagens que possam ser comparados com os indicadores vigentes da condição da superfície do pavimento já normatizados pelos órgãos competentes no país.

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In Brazil, Protected Areas (PAs) are considered the cornerstone for development of national strategies for biodiversity conservation. Considering this point of view we analyzed thirty protected areas belonging to Atlantic Central Corridor of Atlantic Forest in Bahia, aiming to identify and analyze its current level of implementation. Lemos de Sa and Ferreira (2000) methodology which consist of applying a standard scale, where the variation of the level of implementation conforms to a range of 0 to 5 points was used, with appropriate adaptations. After obtaining the data from the implementation level we use the aggregation method of Ward to help visualize the dissimilarity between the protected areas studied. We used an international classification proposed by IUCN (International Union for Conservation of Nature) for that the UCs to be compared with works done in another countries, the UCs considered are in the groups Ia, II, V and VI da IUCN. As results, 50% of protected areas analyzed are reasonably implemented, 40% inadequately implemented, 6.7% are presented only on paper and only 3.3% can be classified as satisfactorily implemented. These areas presents problems in their regularization; deficiency in infrastructure, human and financial resources. Given the results its clear the recurrent fact that conservation areas under study must be effectively implemented and for this to occur environmental policies should be focused on actions to consolidate the goals of conservation strategy.

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Glasses in the system xGeO(2)-(1-x)NaPO3 (0 <= x <= 0.50) were prepared by conventional melting quenching and characterized by thermal analysis, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and P-31 nuclear magnetic resonance (MAS NMR) techniques. The deconvolution of the latter spectra was aided by homonuclear J-resolved and refocused INADEQUATE techniques. The combined analyses of P-31 MAS NMR and O-1s XPS lineshapes, taking charge and mass balance considerations into account, yield the detailed quantitative speciations of the phosphorus, germanium, and oxygen atoms and their respective connectivities. An internally consistent description is possible without invoking the formation of higher-coordinated germanium species in these glasses, in agreement with experimental evidence in the literature. The structure can be regarded, to a first approximation, as a network consisting of P-(2) and P-(3) tetrahedra linked via four-coordinate germanium. As implied by the appearance of P-(3) units, there is a moderate extent of network modifier sharing between phosphate and germanate network formers, as expressed by the formal melt reaction P-(2) + Ge-(4) -> P-(3) + Ge-(3). The equilibrium constant of this reaction is estimated as K = 0.52 +/- 0.11, indicating a preferential attraction of network modifier by the phosphorus component. These conclusions are qualitatively supported by Raman spectroscopy as well as P-31{Na-23} and P-31{Na-23} rotational echo double resonance (REDOR) NMR results. The combined interpretation of O-1s XPS and P-31 MAS NMR spectra shows further that there are clear deviations from a random connectivity scenario: heteroatomic P-O-Ge linkages are favored over homoatomic P-O-P and Ge-O-Ge linkages.

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Abstract Background A popular model for gene regulatory networks is the Boolean network model. In this paper, we propose an algorithm to perform an analysis of gene regulatory interactions using the Boolean network model and time-series data. Actually, the Boolean network is restricted in the sense that only a subset of all possible Boolean functions are considered. We explore some mathematical properties of the restricted Boolean networks in order to avoid the full search approach. The problem is modeled as a Constraint Satisfaction Problem (CSP) and CSP techniques are used to solve it. Results We applied the proposed algorithm in two data sets. First, we used an artificial dataset obtained from a model for the budding yeast cell cycle. The second data set is derived from experiments performed using HeLa cells. The results show that some interactions can be fully or, at least, partially determined under the Boolean model considered. Conclusions The algorithm proposed can be used as a first step for detection of gene/protein interactions. It is able to infer gene relationships from time-series data of gene expression, and this inference process can be aided by a priori knowledge available.

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The Brazilian network for genotyping is composed of 21 laboratories that perform and analyze genotyping tests for all HIV-infected patients within the public system, performing approximately 25,000 tests per year. We assessed the interlaboratory and intralaboratory reproducibility of genotyping systems by creating and implementing a local external quality control evaluation. Plasma samples from HIV-1-infected individuals (with low and intermediate viral loads) or RNA viral constructs with specific mutations were used. This evaluation included analyses of sensitivity and specificity of the tests based on qualitative and quantitative criteria, which scored laboratory performance on a 100-point system. Five evaluations were performed from 2003 to 2008, with 64% of laboratories scoring over 80 points in 2003, 81% doing so in 2005, 56% in 2006, 91% in 2007, and 90% in 2008 (Kruskal-Wallis, p = 0.003). Increased performance was aided by retraining laboratories that had specific deficiencies. The results emphasize the importance of investing in laboratory training and interpretation of DNA sequencing results, especially in developing countries where public (or scarce) resources are used to manage the AIDS epidemic.

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Ordinary yet unique, water is the substance on which life is based. Water seems, at first sight, to be a very simple molecule, consisting of two hydrogen atoms attached to one oxygen. Its small size belies the complexity of its action and its numerous anomalies, central to a broad class of important phenomena, ranging from global current circulation, terrestrial water and CO2 cycles to corrosion and wetting. The explanation of this complex behavior comes from water's unique ability to form extensive three-dimensional networks of hydrogen-bonds, whose nature and structures, in spite of a great deal of efforts involving a plethora of experimental and theoretical techniques, still lacks a complete scientific understanding. This thesis is devoted to the study of the local structure of hydrogen-bonded liquids, with a particular emphasis on water, taking advantage of a combination of core-level spectroscopies and density functional theory spectra calculations. X-ray absorption, in particular, is found to be sensitive to the local hydrogen-bond environment, thus offering a very promising tool for spectroscopic identification of specific structural configurations in water, alcohols and aqueous solutions. More specifically, the characteristic spectroscopic signature of the broken hydrogen-bond at the hydrogen side is used to analyze the structure of bulk water, leading to the finding that most molecules are arranged in two hydrogen-bond configurations, in contrast to the picture provided by molecular dynamics simulations. At the liquid-vapor interface, an interplay of surface sensitive measurements and theoretical calculations enables us to distinguish a new interfacial species in equilibrium with the gas. In a similar approach the cluster form of the excess proton in highly concentrated acid solutions and the different coordination of methanol at the vacuum interface and in the bulk can also be clearly identified. Finally the ability of core-level spectroscopies, aided by sophisticated density functional theory calculations, to directly probe the valence electronic structure of a system is used to observe the nature of the interaction between water molecules and solvated ions in solution. Water around transition metal ions is found to interact with the solute via orbital mixing with the metal d-orbitals. The hydrogen-bond between water molecules is explained in terms of electrostatic interactions enhanced by charge rehybridization in which charge transfer between connecting molecules is shown to be fundamental.

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Sociology of work in Italy revived at the end of WWII, after thirty years of forced oblivion. This thesis examines the history of discipline by considering three paths that it followed from its revival up to its institutionalization: the influence of the productivity drive, the role of trade unions and the activity of early young researchers. European Productivity Agency's Italian office Comitato Nazionale per la Produttività propagandised studies on management and on the effects of the industrialization on work and society. Academicians, technicians, psychologists who worked for CNP started rethinking sociology of work, but the managerial use of sociology was unacceptable for both trade unions and young researchers. So “free union” CISL created a School in Florence with an eager attention to social sciences as a medium to become a new model union, while Marxist CGIL, despite its ideological aversion to sociology, finally accepted the social sciences lexicon in order to explain the work changes and to resist against the employers' association offensive. On the other hand, political and social engagement led a first generation of sociologists to study social phenomenon in the recently industrialized Italy by using the sociological analysis. Finally, the thesis investigate the cultural transfers from France, whose industrial sociology (sociologie du travail) was considered as a reference in continental Europe. Nearby the wide importance of French sociologie, financially aided by planning institutions in order to employ it in the industrial reconstruction, other minor experiences such as the social surveys accomplished by worker-priests in the suburbs of industrial cities and the heterodox Marxism of the review “Socialisme ou Barbarie” influenced Italian sociology of work.

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Es werden Krankheitserleben und Behandlungsvoraussetzungen als Prädiktoren für den Erfolg stationärer Psychosomatischer Therapie anhand der vorliegenden Studie, die 125 Patienten einschliesst, überprüft. Dies geschieht mit Hilfe der Achse I der Operationalisierten Psychodynamischen Diagnostik (OPD).Die OPD wurde von der Arbeitsgruppe-OPD 1996 in Ergänzung zu der ICD-10 (International Classification of Diseases) herausgegeben und bietet für die Psyche betreffende Erkrankungen zusätzlich zu den rein deskriptiven Klassifikationen der ICD eine Klassifikationsmöglichkeit auf der Basis der Psychoanalyse und Psychodynamik an. Die erste der insgesamt fünf Achsen der OPD bezieht sich dabei auf das Krankheitserleben und die Behandlungsvoraussetzungen des Patienten.Der Erfolg der Therapie wird bis 1 Jahr nach dem Ende der Therapie zu drei verschiedenen Zeitpunkten durch Befragungen der Patienten erfasst. Die Ergebnisse zeigen für einzelne der Items der Achse I der OPD deutliche Zusammenhänge mit dem später eingetretenen Erfolg der Therapie. Dies gilt insbesondere für den Schweregrad des psychischen Befundes, den Leidensdruck, die Beeinträchtigung des Selbsterlebens, die Motivation zur Psychotherapie und die psychische Symptomdarbietung (Items 2, 3, 4, 11 und 15).Des weiteren werden zwei Faktorenlösungen erstellt, welche die 19 einzelnen Items der Achse I der OPD zu Faktoren zusammenfassen. Im Vergleich mit den bereits vorhandenen Faktorenlösungen zeigen sich aufgrund der Uneinheitlichkeit Probleme für eine mögliche Verwendung in der Praxis.

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The Pelagonian Zone and the Vardar Zone in Greece represent the western part of the Hellenide hinterland (Internal Hellenides). While the Pelagonian Zone comprises predominantly crystalline basement and sedimentary cover rocks, the Vardar Zone has long been regarded as an ophiolite-decorated suture zone separating the Pelagonian Zone from the Serbo-Macedonian Massif to the east. Felsic basement rocks from both areas, with the main focus put on the Pelagonian Zone, were dated in order to identify the major crust-forming episodes and to improve the understanding of the evolutionary history of the region. The interpretation of the single-zircon geochronology results was aided by geochemical investigations. The majority of the basement rocks from the Pelagonian Zone yielded Permo-Carboniferous intrusion ages around 300 Ma, underlining the importance of this crust-forming event for the Internal Hellenides of Greece. Geochemically these basement rocks are classified as subduction-related granitoids, which formed in an active continental margin setting. An important result was the identification of a Precambrian crustal unit within the crystalline basement of the Pelagonian Zone. Orthogneisses from the NW Pelagonian Zone yielded Neoproterozoic ages of c. 700 Ma and are so far the oldest known rocks in Greece. These basement rocks, which are also similar to active margin granitoids, were interpreted as remnants of a terrane, the Florina Terrane, which can be correlated to a Pan-African or Cadomian arc. Since the gneisses contain inherited zircons of Middle to Late Proterozoic ages, the original location of the Florina Terrane was probably at the northwestern margin of Gondwana. In the Vardar Zone an important phase of Upper Jurassic felsic magmatism is documented by igneous formation ages ranging from 155 to 164 Ma. The chemical and isotopic composition of these rocks is also in accord with their formation in a volcanic-arc setting at an active continental margin. Older continental material incorporated in the Vardar Zone is documented by 319-Ma-old gneisses and by inherited zircons of mainly Middle Palaeozoic ages. The prevalence of subduction-related igneous rocks indicates that arc formation and accretion orogeny were the most important processes during the evolution of this part of the Internal Hellenides. The geochronological results demonstrate that most of the Pelagonian Zone and the Vardar Zone crystalline basement formed during distinct pre-Alpine episodes at c. 700, 300 and 160 Ma with a predominance of the Permo-Carboniferous magmatic phase.

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Over the last three decades, sensors based on the phenomenon of surface plasmon resonance have proven particularly suitable for real time thin film characterization, gas detection, biomolecular interaction examination and to supplement electrochemical methods. Systems based on prism coupling have been combined with fluorescence detection under the name of surface plasmon fluorescence spectroscopy to increase sensitivity even further. Alternatively, metal gratings can be employed to match photons for plasmon resonance. The real time monitoring of binding reactions not yet been reported in the combination of fluorescence detection and grating coupling. Grating-based systems promise more competitive products, because of reduced operating costs, and offer benefits for device engineering. This thesis is comprised of a comprehensive study of the suitability of grating coupling for fluorescence based analyte detection. Fundamental properties of grating coupled surface plasmon fluorescence spectroscopy are described, as well as issues related to the commercial realization of the method. Several new experimental techniques are introduced and demonstrated in order to optimize performance in certain areas and improve upon capabilities in respect to prism-based systems. Holographically fabricated gratings are characterized by atomic force microscopy and optical methods, aided by simulations and profile parameters responsible for efficient coupling are analyzed. The directional emission of fluorophores immobilized on a grating surface is studied in detail, including the magnitude and geometry of the fluorescence emission pattern for different grating constants and polarizations. Additionally, the separation between the minimum of the reflected intensity and the maximum fluorescence excitation position is examined. One of the key requirements for the commercial feasibility of grating coupling is the cheap and faithful mass production of disposable samples from a given master grating. The replication of gratings is demonstrated by a simple hot embossing method with good reproducibility to address this matter. The in-situ fluorescence detection of analyte immobilization and affinity measurements using grating coupling are described for the first time. The physical factors related to the sensitivity of the technique are assessed and the lower limit of detection of the technique is determined for an exemplary assay. Particular attention is paid to the contribution of bulk fluorophores to the total signal in terms of magnitude and polarization of incident and emitted light. Emission from the bulk can be a limiting factor for experiments with certain assay formats. For that reason, a novel optical method, based on the modulation of both polarization and intensity of the incident beam, is introduced and demonstrated to be capable of eliminating this contribution.