Automatic segmentation of digital images applied in cardiac medical images

The digital image processing has been applied in several areas, especially where it is necessary use tools for feature extraction and to get patterns of the studied images. In an initial stage, the segmentation is used to separate the image in parts that represents a interest object, that may be used in a specific study. There are several methods that intends to perform such task, but is difficult to find a method that can easily adapt to different type of images, that often are very complex or specific. To resolve this problem, this project aims to presents a adaptable segmentation method, that can be applied to different type of images, providing an better segmentation. The proposed method is based in a model of automatic multilevel thresholding and considers techniques of group histogram quantization, analysis of the histogram slope percentage and calculation of maximum entropy to define the threshold. The technique was applied to segment the cell core and potential rejection of tissue in myocardial images of biopsies from cardiac transplant. The results are significant in comparison with those provided by one of the best known segmentation methods available in the literature. © 2010 IEEE.

Bone mineral density on conventional and digitized images under different parameters of digitization and storage

Aim: To assess the bone mineral density on conventional and digitized images, comparing whether different parameters of digitization and storage change these values. Methods: Twenty radiographs were taken from five partially dentulous dry mandibles with an aluminum 7-mm stepwedge placed on the superior edge of the film. After processing, the films were digitized with a resolution of 600 and 2,400 d.p.i. and saved as TIFF and JPEG files. On every conventional and digitized image, circular regions of interest were selected for densitometry and radiographic contrast analysis. Results: Pearson's correlation coefficient showed a significant and strong mean gray values association between digitized and conventional images, differing from radiographic contrast that did not show a significant association. ANOVA did not reveal a statistically significant difference in bone density and radiographic contrast among the four digitized image groups, but the conventional image contrast was significantly lower. Conclusions: Bone mineral density did not differ in both conventional and digitized images. The parameters of image compression and resolution, tested in this study, did not change the results of densitometry and digitization process increased the radiographic contrast.

Implementação de um controle digital para o compensador regenerativo de potência ativa

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Arquitetura da informação para biblioteca digital colaborativa: uma proposta de um sistema de interação

Pós-graduação em Ciência da Informação - FFC

Convergência digital de objetos de aprendizagem Scorm

Pós-graduação em Ciência da Computação - IBILCE

Análise comparativa entre o sistema digital Digora e a digitalização da radiografia convencional na avaliação da densidade radiográfica do processo de reparo alveolar

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Preservação digital na gestão da informação: um modelo processual para as instituições de ensino superior

Pós-graduação em Ciência da Informação - FFC

Gestão de imagens em movimento de matérias jornalísticas em banco de dados na TV Digital

Pós-graduação em Televisão Digital: Informação e Conhecimento - FAAC

DIGITAL LIBRARIES AND LEARNING OBJECTS REPOSITORIES

Discusses the technological changes that affects learning organizations as well as the human, technical, legal and sustainable aspects regarding learning objects repositories creation, maintenance and use. It presents concepts of information objects and learning objects, the functional requirements needed to their storage at Learning Management Systems. The role of Metadata is reviewed concerning learning objects creation and retrieval, followed by considerations about learning object repositories models, community participation/collaborative strategies and potential derived metrics/indicators. As a result of this desktop research, it can be said that not only technical competencies are critical to any learning objects repository implementation, but it urges that an engaged community of interest be establish as a key to support a learning object repository project. On that matter, researchers are applying Activity Theory (Vygostky, Luria y Leontiev) in order to seek joint perceptions and actions involving learning objects repository users, curators and managers, perceived as critical assets to a successful proposal.

In vitro study on radiographic gray levels of biomaterials using two digital image methods

PURPOSE: To compare the direct and indirect radiographic methods for assessing the gray levels of biomaterials employing the Digora for Windows and the Adobe Photoshop CS2 systems. METHODS: Specimens of biomaterials were made following manusfacturer's instructions and placed on phosphor storage plates (PSP) and on radiographic film for subsequent gray level assessment using the direct and indirect radiographic method, respectively. The radiographic density of each biomaterial was analyzed using Adobe Photoshop CS2 and Digora for Windows software. RESULTS: The distribution of gray levels found using the direct and indirect methods suggests that higher exposure times are correlated to lower reproducibility rates between groups. CONCLUSION: The indirect method is a feasible alternative to the direct method in assessing the radiographic gray levels of biomaterials, insofar as significant reproducibility was observed between groups for the exposure times of 0.2 to 0.5 seconds.

Repositório digital em biblioteca acadêmica: desafio na garantia de acesso para informações em saúde pública

Introdução: A Faculdade de Saúde Pública, assim como a Universidade de São Paulo, tem, na sua produção intelectual, literatura científica de relevância para a área da saúde, que sempre está a frente no desenvolvimento de tecnologia e na organização da informação. É importante que essa produção esteja acessível à sua comunidade, técnicos e profissionais da saúde, além da população em geral. A Biblioteca da FSP/USP, por ser uma das curadoras desse conhecimento, constitui-se, além de memória bibliográfica institucional de importância para a história da saúde pública brasileira, em uma fonte de informação valiosa, cujo acesso deve ser garantido. Objetivo: Apresentar o desenvolvimento de um repositório digital em uma biblioteca acadêmica. Métodos: A oportunidade da criação do repositório surgiu como parte de um projeto de infraestrutura de pesquisa da Fundação de Amparo à Pesquisa do Estado de São Paulo. Na sua concepção foi previsto o uso da plataforma DSpace e o padrão de metadados Dublin Core, com adaptações. para sua implantação foram adquiridos: dois servidores e respectivos no-breaks, um “storage” com capacidade de 8 terabytes e dois escâneres com design especial para acomodação de lombadas. Uma equipe de informática responsabilizou-se pela instalação e configuração dos softwares, e a de marketing desenvolveu o design gráfico. Resultado e discussão: O repositório dispõe de cerca de 600 registros, com os devidos níveis de possibilidade de acesso – aberto, restrito ou embargado –, em fase de inauguração (prevista para 2012). A equipe do projeto é formada por profissionais com experiência e conhecimento em diversas áreas: metadados, preservação digital, usabilidade, design gráfico, marketing, direitos autorais, arquivamento de dados, backups, sistemas de autenticação e firewalls, entre outros. Parte da digitalização dos documentos foi executada por empresa especializada, que também treinou a equipe da Biblioteca, tendo sido digitalizadas, até o momento, 205.000 páginas. A Biblioteca instalou uma Oficina de Digitalização para dar continuidade ao repositório, que é atrelado à área de Desenvolvimento de Coleções. Além da produção intelectual da Faculdade, esse repositório conterá documentos da história do Estado de São Paulo e a do Brasil, no que se refere à informação científica em saúde publica. Entre sua concepção e implantação foram dois anos de trabalho da equipe da Biblioteca. Conclusões e comentários: O Repositório Digital da Biblioteca da FSP/USP foi desafiante desde sua concepção até o financiamento, capacitação e manutenção de equipes, entre eles a customização do DSpace. Da mesma forma, foi uma oportunidade para a equipe ampliar seu “know-how”. Os impactos positivos de um projeto desse porte incidem sobre o acesso ao conhecimento muito mais facilitado, de forma gratuita e universal, agregando maior valor aos registros das bases bibliográficas à medida que disponibiliza links para os textos completos, áudios, vídeos e imagens, para a divulgação da ciência.

Performance evaluation of detectors for digital radiography

To date the hospital radiological workflow is completing a transition from analog to digital technology. Since the X-rays digital detection technologies have become mature, hospitals are trading on the natural devices turnover to replace the conventional screen film devices with digital ones. The transition process is complex and involves not just the equipment replacement but also new arrangements for image transmission, display (and reporting) and storage. This work is focused on 2D digital detector’s characterization with a concern to specific clinical application; the systems features linked to the image quality are analyzed to assess the clinical performances, the conversion efficiency, and the minimum dose necessary to get an acceptable image. The first section overviews the digital detector technologies focusing on the recent and promising technological developments. The second section contains a description of the characterization methods considered in this thesis categorized in physical, psychophysical and clinical; theory, models and procedures are described as well. The third section contains a set of characterizations performed on new equipments that appears to be some of the most advanced technologies available to date. The fourth section deals with some procedures and schemes employed for quality assurance programs.

The twofold role of Cloud Computing in Digital Forensics: target of investigations and helping hand to evidence analysis

This PhD thesis discusses the impact of Cloud Computing infrastructures on Digital Forensics in the twofold role of target of investigations and as a helping hand to investigators. The Cloud offers a cheap and almost limitless computing power and storage space for data which can be leveraged to commit either new or old crimes and host related traces. Conversely, the Cloud can help forensic examiners to find clues better and earlier than traditional analysis applications, thanks to its dramatically improved evidence processing capabilities. In both cases, a new arsenal of software tools needs to be made available. The development of this novel weaponry and its technical and legal implications from the point of view of repeatability of technical assessments is discussed throughout the following pages and constitutes the unprecedented contribution of this work

LoneStar : Design and evaluation of an energy-efficient, disk-based archival storage system

Bandlaufwerke waren bisher die vorherrschende Technologie, um die anfallenden Datenmengen in Archivsystemen zu speichern. Mit Zugriffsmustern, die immer aktiver werden, und Speichermedien wie Festplatten die kostenmäßig aufholen, muss die Architektur vor Speichersystemen zur Archivierung neu überdacht werden. Zuverlässigkeit, Integrität und Haltbarkeit sind die Haupteigenschaften der digitalen Archivierung. Allerdings nimmt auch die Zugriffsgeschwindigkeit einen erhöhten Stellenwert ein, wenn aktive Archive ihre gesamten Inhalte für den direkten Zugriff bereitstellen. Ein band-basiertes System kann die hierfür benötigte Parallelität, Latenz und Durchsatz nicht liefern, was in der Regel durch festplattenbasierte Systeme als Zwischenspeicher kompensiert wird.rnIn dieser Arbeit untersuchen wir die Herausforderungen und Möglichkeiten ein festplattenbasiertes Speichersystem zu entwickeln, das auf eine hohe Zuverlässigkeit und Energieeffizienz zielt und das sich sowohl für aktive als auch für kalte Archivumgebungen eignet. Zuerst analysieren wir die Speichersysteme und Zugriffsmuster eines großen digitalen Archivs und präsentieren damit ein mögliches Einsatzgebiet für unsere Architektur. Daraufhin stellen wir Mechanismen vor um die Zuverlässigkeit einer einzelnen Festplatte zu verbessern und präsentieren sowie evaluieren einen neuen, energieeffizienten, zwei- dimensionalen RAID Ansatz der für „Schreibe ein Mal, lese mehrfach“ Zugriffe optimiert ist. Letztlich stellen wir Protokollierungs- und Zwischenspeichermechanismen vor, die die zugrundeliegenden Ziele unterstützen und evaluieren das RAID System in einer Dateisystemumgebung.

From Money Storage to Money Store: Openness and Transparency in Bank Architecture

In the middle of the twentieth century, banks changed from ‘closed’ designs signifying wealth, security, and safety to ‘open’ designs signifying hospitality, honesty, and transparency as the perception of money changed from a passive physical substance to be slowly accumulated to an active notational substance to be kept in motion. If money is saved, customers must trust that the bank is secure and their money will be there when they want it; if money is invested, customers must trust that it is being done openly and honestly and they are being well-advised. Architecture visually communicates that the institution can be trusted in the requisite way.