50 resultados para Segmentação de Imagem

em Universidade Federal do Rio Grande do Norte(UFRN)


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Automatic detection of blood components is an important topic in the field of hematology. The segmentation is an important stage because it allows components to be grouped into common areas and processed separately and leukocyte differential classification enables them to be analyzed separately. With the auto-segmentation and differential classification, this work is contributing to the analysis process of blood components by providing tools that reduce the manual labor and increasing its accuracy and efficiency. Using techniques of digital image processing associated with a generic and automatic fuzzy approach, this work proposes two Fuzzy Inference Systems, defined as I and II, for autosegmentation of blood components and leukocyte differential classification, respectively, in microscopic images smears. Using the Fuzzy Inference System I, the proposed technique performs the segmentation of the image in four regions: the leukocyte’s nucleus and cytoplasm, erythrocyte and plasma area and using the Fuzzy Inference System II and the segmented leukocyte (nucleus and cytoplasm) classify them differentially in five types: basophils, eosinophils, lymphocytes, monocytes and neutrophils. Were used for testing 530 images containing microscopic samples of blood smears with different methods. The images were processed and its accuracy indices and Gold Standards were calculated and compared with the manual results and other results found at literature for the same problems. Regarding segmentation, a technique developed showed percentages of accuracy of 97.31% for leukocytes, 95.39% to erythrocytes and 95.06% for blood plasma. As for the differential classification, the percentage varied between 92.98% and 98.39% for the different leukocyte types. In addition to promoting auto-segmentation and differential classification, the proposed technique also contributes to the definition of new descriptors and the construction of an image database using various processes hematological staining

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A 3D binary image is considered well-composed if, and only if, the union of the faces shared by the foreground and background voxels of the image is a surface in R3. Wellcomposed images have some desirable topological properties, which allow us to simplify and optimize algorithms that are widely used in computer graphics, computer vision and image processing. These advantages have fostered the development of algorithms to repair bi-dimensional (2D) and three-dimensional (3D) images that are not well-composed. These algorithms are known as repairing algorithms. In this dissertation, we propose two repairing algorithms, one randomized and one deterministic. Both algorithms are capable of making topological repairs in 3D binary images, producing well-composed images similar to the original images. The key idea behind both algorithms is to iteratively change the assigned color of some points in the input image from 0 (background)to 1 (foreground) until the image becomes well-composed. The points whose colors are changed by the algorithms are chosen according to their values in the fuzzy connectivity map resulting from the image segmentation process. The use of the fuzzy connectivity map ensures that a subset of points chosen by the algorithm at any given iteration is the one with the least affinity with the background among all possible choices

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The vascular segmentation is important in diagnosing vascular diseases like stroke and is hampered by noise in the image and very thin vessels that can pass unnoticed. One way to accomplish the segmentation is extracting the centerline of the vessel with height ridges, which uses the intensity as features for segmentation. This process can take from seconds to minutes, depending on the current technology employed. In order to accelerate the segmentation method proposed by Aylward [Aylward & Bullitt 2002] we have adapted it to run in parallel using CUDA architecture. The performance of the segmentation method running on GPU is compared to both the same method running on CPU and the original Aylward s method running also in CPU. The improvemente of the new method over the original one is twofold: the starting point for the segmentation process is not a single point in the blood vessel but a volume, thereby making it easier for the user to segment a region of interest, and; the overall gain method was 873 times faster running on GPU and 150 times more fast running on the CPU than the original CPU in Aylward

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The segmentation of an image aims to subdivide it into constituent regions or objects that have some relevant semantic content. This subdivision can also be applied to videos. However, in these cases, the objects appear in various frames that compose the videos. The task of segmenting an image becomes more complex when they are composed of objects that are defined by textural features, where the color information alone is not a good descriptor of the image. Fuzzy Segmentation is a region-growing segmentation algorithm that uses affinity functions in order to assign to each element in an image a grade of membership for each object (between 0 and 1). This work presents a modification of the Fuzzy Segmentation algorithm, for the purpose of improving the temporal and spatial complexity. The algorithm was adapted to segmenting color videos, treating them as 3D volume. In order to perform segmentation in videos, conventional color model or a hybrid model obtained by a method for choosing the best channels were used. The Fuzzy Segmentation algorithm was also applied to texture segmentation by using adaptive affinity functions defined for each object texture. Two types of affinity functions were used, one defined using the normal (or Gaussian) probability distribution and the other using the Skew Divergence. This latter, a Kullback-Leibler Divergence variation, is a measure of the difference between two probability distributions. Finally, the algorithm was tested in somes videos and also in texture mosaic images composed by images of the Brodatz album

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Image segmentation is the process of subdiving an image into constituent regions or objects that have similar features. In video segmentation, more than subdividing the frames in object that have similar features, there is a consistency requirement among segmentations of successive frames of the video. Fuzzy segmentation is a region growing technique that assigns to each element in an image (which may have been corrupted by noise and/or shading) a grade of membership between 0 and 1 to an object. In this work we present an application that uses a fuzzy segmentation algorithm to identify and select particles in micrographs and an extension of the algorithm to perform video segmentation. Here, we treat a video shot is treated as a three-dimensional volume with different z slices being occupied by different frames of the video shot. The volume is interactively segmented based on selected seed elements, that will determine the affinity functions based on their motion and color properties. The color information can be extracted from a specific color space or from three channels of a set of color models that are selected based on the correlation of the information from all channels. The motion information is provided into the form of dense optical flows maps. Finally, segmentation of real and synthetic videos and their application in a non-photorealistic rendering (NPR) toll are presented

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Digital image segmentation is the process of assigning distinct labels to different objects in a digital image, and the fuzzy segmentation algorithm has been used successfully in the segmentation of images from several modalities. However, the traditional fuzzy segmentation algorithm fails to segment objects that are characterized by textures whose patterns cannot be successfully described by simple statistics computed over a very restricted area. In this paper we present an extension of the fuzzy segmentation algorithm that achieves the segmentation of textures by employing adaptive affinity functions as long as we extend the algorithm to tridimensional images. The adaptive affinity functions change the size of the area where they compute the texture descriptors, according to the characteristics of the texture being processed, while three dimensional images can be described as a finite set of two-dimensional images. The algorithm then segments the volume image with an appropriate calculation area for each texture, making it possible to produce good estimates of actual volumes of the target structures of the segmentation process. We will perform experiments with synthetic and real data in applications such as segmentation of medical imaging obtained from magnetic rosonance

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Embora tenha sido proposto que a vasculatura retínica apresenta estrutura fractal, nenhuma padronização do método de segmentação ou do método de cálculo das dimensões fractais foi realizada. Este estudo objetivou determinar se a estimação das dimensões fractais da vasculatura retínica é dependente dos métodos de segmentação vascular e dos métodos de cálculo de dimensão. Métodos: Dez imagens retinográficas foram segmentadas para extrair suas árvores vasculares por quatro métodos computacionais (“multithreshold”, “scale-space”, “pixel classification” e “ridge based detection”). Suas dimensões fractais de “informação”, de “massa-raio” e “por contagem de caixas” foram então calculadas e comparadas com as dimensões das mesmas árvores vasculares, quando obtidas pela segmentação manual (padrão áureo). Resultados: As médias das dimensões fractais variaram através dos grupos de diferentes métodos de segmentação, de 1,39 a 1,47 para a dimensão por contagem de caixas, de 1,47 a 1,52 para a dimensão de informação e de 1,48 a 1,57 para a dimensão de massa-raio. A utilização de diferentes métodos computacionais de segmentação vascular, bem como de diferentes métodos de cálculo de dimensão, introduziu diferença estatisticamente significativa nos valores das dimensões fractais das árvores vasculares. Conclusão: A estimação das dimensões fractais da vasculatura retínica foi dependente tanto dos métodos de segmentação vascular, quanto dos métodos de cálculo de dimensão utilizados

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The growing importance of tourism in overall economic activity worldwide has favored the intensification of competition among cities that seek to create environments attractive to tourists and potential investors. It has been common practice to import characteristics of the business environment in the public management of cities. The city marketing is a key tool used by public leaders to promote a linkage between the tourism image and urban image and involves, in addition to promoting the image of the city, the planning of interventions in urban space, trying to formulate a positive image of the city able to facilitate the deployment of capital. This research seeks to understand the nature of city marketing as part of contemporary urban management and analyzes how is its application in decisions concerning the promotion of tourism in Natal/RN. The approach of this research is qualitative, exploratory and descriptive, in which respondents were the main leaders of two of the official tourism site, the Empresa Potiguar de Promoção Turística and the Secretaria Municipal de Turismo e Desenvolvimento Econômico. It was found that there is a strong articulation of public power with private enterprise in the design and conduct of the actions of urban marketing, that from the survey data show that the behavior of target markets provide guidelines for taking strategic decisions relating to tourism. Sun and sea are some key elements explored to form the image of Natal and to authorize the sale of the city as a tropical paradise. However, there is an increase in the diversification of tourism products, seeking to increase flow to the segments of ecotourism, adventure, business and culture. It s also growing the use of local culture as a tourism product, however, the cultural representation focuses on superficial values and does not bring to light the social and historical richness that the city has. Public authorities use the city marketing strategies as a means able to maximize the attractiveness of Natal urban space to investors, business groups and tourists. It can be observed that urban managers seek solutions that can continuously increase the tours, which often manifests in interventions that focus the tourist areas of the city, in oposition of those who do not contribute to a positive reading of the city, which ultimately generate the worsening of spacial and social inequalities

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This study shows the results of an exploratory-descriptive research that aimed to identify the latent dimensions of communication, as well as finding relations between such dimensions and organizational image. The sample came to a total of 267 respondents, being 89 managers or owners and 178 salespeople of clothing and footwear stores that are situated in the main five shopping centers located in Natal, capital of Rio Grande do Norte. The collection of the data was made by the use of two structuralized and validated instruments, being the answers measured in the likert scale of 6 points. For the measurement of communication it was used the instrument developed by Downs and Hazen (2002), made up of 8 latent dimensions and 32 indicators. For the image it was used the model of Mael and Ashforth (1992) that contains 5 indicators. The analysis of the data was made through of the use of statistical techniques of factorial analysis and structural equations modeling. The results of the factorial analysis demonstrated communication as being formed by five latent dimensions. The modeling, on the other hand, demonstrated to exist positive relations between communication and organizational image, whose results revealed that the image is influenced by the communication with the supervisor, by the organizational integration and as being stronger explained by the vertical communication

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Tendo como base os conceitos de espaço, lugar, ambiente e imagem, sob as vertentes da Arquitetura e Urbanismo, Geografia e Psicologia Ambiental, esta pesquisa teve como objetivo averiguar a percepção de estudantes da Escola Agrícola de Jundiaí (EAJ UFRN) a fim de identificar aspectos das interrelações pessoa-ambiente que diferenciam tal escola de outras instituições. A coleta de dados utilizou multimétodos e investigou um grupo de alunos residentes na Escola que cursavam o ensino médio e técnico em agropecuária em 2006, analisando seus discursos, comportamentos e atitudes de modo a identificar os principais elementos da imagem sócio-ambiental da EAJ. Os resultados apontaram locais, práticas sociais e símbolos representativos da instituição, indicando espaços (construídos e naturais) adequados/inadequados às necessidades/expectativas dos estudantes incluindo a ampliação da interdisciplinaridade no conjunto de suas atividades. Além disso, a fim de incrementar a análise sócio-ambiental em instituições que promovem experiências exitosas, recomenda-se que os aspectos cotidiano e tempo sejam mais profundamente investigados em estudos futuros na área

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Body image is the figure of our bodies built in our minds and the degree of dissatisfaction is often associated with risk factors identified by anthropometric measures. The purpose of this descriptive study was to evaluate the risk factors associated to morphological and functional variables associate to the perception of auto-image in middle-aged walkers of the south zone of the city of Natal. A hundred and thirty volunteers had been evaluated in four groups in function of the gender and age group. As measurement evaluations were used an auto-image perception questionnaire proposed by Stunkart of nine silhouettes numbered for both gender was applied; a weighing machine equipped with stadiometer for the body mass (kg) and stature (m) and the body mass index (kg/m2) that was calculated with base in measures of the body weight and stature and classified according to norms of the National Institute of Health (2000) as well as the systolic and diastolic blood pressure by a electronic digital device (DIGITRONIC). A metal anthropometric tape was used for the waist to hip ratio (WHR). It was used Analyses of variance (ANOVA) one-way, post hoc of Tukey and correlation of Spearman for the nonparametric data adopting the level of ρ≤ 0,05 for rejection of the null hypothesis. The body mass index indicated high factors of risk in the consisting groups. In all the groups were registered the desire to reduce their silhouettes. The body weight shows reduced when compared with the younger group in the male group of superior age group, while in the female group the inverse one occurs. The autoimage perception is associated with the classification of the waist to hip ratio in the female gender in the age group of the 50 to the 59 years and in the classification of the body mass index of all constituted groups. Significant associations had not been found for classification of the systolic and diastolic blood pressure in relation to the auto-image 41 perception. This thesis presents relation of interdisciplinarity and its contents have application in the fields of Physical Education, Medicine, Physiotherapy and Nursing

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This paper examines two aspects. First, the symbolic dimension of politics and some of the elements that make up this universe, as the scenario, the representation, the myth, the spectacle, the media and the political and electoral marketing. We assume that the policy brings together a set of traits related to both reason and the human subjectivity, and can not be summed up in just a few calculations based on rationality. In the case of elections, in a process (ritual, according Irlys Barrier) of choice, there is a meeting of two systems of representations: to that transmitted by a political actor, in a scene from a particular context, based on a life trajectory unique, and the other from the public, crossed by social relations, situations own wishes, desires, expectations and unique perspectives. Between them there are the means of mass media (especially television), and with them the advent of language media and advertising applied to politics, changing the layout of public visibility and inaugurating what Rejane Accioly Carvalho will call the "aesthetics of mostrabilidade". This does not necessarily mean a preponderance of media on politics as a whole but only its adaptation to that with regard to contact with the public, the ad extra portion of the policy, according to Wilson Gomes. In a second aspect, try to apply these elements to a specific study to verify them in building an effective public image, in this case, the current governor of Rio Grande do Norte, Wilma de Faria. The concept of public image is from the book of Wilson Gomes The transformation was visible in the mass media, and relates to a conceptual image to fix "personality traits" through political history, personal conduct, action of image makers and the public reception. For this we will review some videos aired on Free Time for political propaganda in the years 2002 and 2006.

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The following research aims to address the image of the ordinary person in the films of the Pontos de Cultura (Culture Points) in Natal-RN. About ten years the Federal Government of Brazil created the Cultura Viva (Living Culture) program. It enabled the State to support financially civil society organizations that had developed cultural works in communities across the country. Along with the resources the program developed, in parallel, another action, Cultura Digital (Digital culture), intended to bring the tools of digital technology for people who have never had access to them. As a result of these initiatives were produced short films. These films were characterized by the presence of the image of the ordinary person. The creation of this type of cultural product was benefited by state initiative, however, it was inserted within a historical, political and cultural construction whose research was necessary for this image understood to be understood by its importance: it is the expression of emancipation the ordinary person and not just as a consumer of culture, it identifies them as the protagonists of the society and recognizes their vital role in its organization

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Descreve-se aqui a formação da Imagem Pública de Luis Inácio Lula da Silva através do Horário Gratuito de Propaganda Eleitoral, nas quatro eleições presidenciais que marcaram o período de democratização do País: 1989, 1994, 1998 e 2002. O fato de um candidato contrário às elites, três vezes derrotado em eleições anteriores, conseguir convencer através da mídia a elegê-lo eleitores que votavam antes em seus adversários, demonstra que a democracia representativa brasileira é institucionalmente compatível com regime de informação imposto pelos meios de comunicação de massa na sociedade atual? Além de comprovar a preponderância da Imagem Pública em processos eleitorais em que o Cenário de Representação da Política se caracteriza pela imprevisibilidade, a pesquisa constatou ainda que a atual luta política, mais que uma luta meramente pela visibilidade imposta pela TV e pelos meios de comunicação em geral ainda é uma disputa política. E que a mídia enquadra a política, mas também é por ela agendada, principalmente em momentos de grande incerteza política e/ou pouca previsibilidade eleitoral

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The main focus of this thesis is the formation of a mathematical teacher at a college institution. The general aim is to describe and to analyze the formation process of a mathematical teacher which is an undergraduate student in Mathematics at the Instituto de Educação Superior Presidente Kennedy IFESP, in Natal-RN. It is based on a qualitative ethnographic approach, and has its theoretical anchorage in the (auto)biographical narratives, the social representative theories, and the mathematical education. The number of participants in this investigation was 12 undergraduate students, which corresponds to 25% of the total number of students. The corpus utilized in our analysis included 48 (auto)biographical essays, 12 (auto)biographies (formation's memories), and 12 contextualization files, besides the research's diary. The sources were obtained from the whole program of studies, i.e. from November 2003 to December 2006. The analysis revealed that the reminiscences of the 12 students' academic trajectory influenced their professional formation, since their images of a mathematical teacher were intrinsically related to the one they had before. These representations were being either demolished or constructed in a network along the assertive image of their profession, changing afterwards the mathematical representation and the teaching way of this discipline. Our study also shows that the beginning of their teacher career was marked by mechanical practices influenced by their old teachers. The (trans)formation of themselves and their teaching practices happened in a smooth way as soon as they increased their knowledgements in Mathematics, and it reflected upon the way they learned mathematics. The writing of their (auto)biographies helped the set up of new knowledgements, leaving to a self-consciousness as well as a self-formation, and contributed for the construction of a new way to see and to live the profession. Therefore, a mathematical teacher, for the undergraduate students of the IFESP involved in this work, is made at the interface of the familiar, academic, and professional context, besides the reflexive writings about the formation path, the way of life and the relationships among them