Avaliação da caracterização de lesões em mamografia com recurso a sistemas CAD (Computer-Aided Diagnosis)

Os sistemas Computer-Aided Diagnosis (CAD) auxiliam a deteção e diferenciação de lesões benignas e malignas, aumentando a performance no diagnóstico do cancro da mama. As lesões da mama estão fortemente correlacionadas com a forma do contorno: lesões benignas apresentam contornos regulares, enquanto as lesões malignas tendem a apresentar contornos irregulares. Desta forma, a utilização de medidas quantitativas, como a dimensão fractal (DF), pode ajudar na caracterização dos contornos regulares ou irregulares de uma lesão. O principal objetivo deste estudo é verificar se a utilização concomitante de 2 (ou mais) medidas de DF – uma tradicionalmente utilizada, a qual foi designada por “DF de contorno”; outra proposta por nós, designada por “DF de área” – e ainda 3 medidas obtidas a partir destas, por operações de dilatação/erosão e por normalização de uma das medidas anteriores, melhoram a capacidade de caracterização de acordo com a escala BIRADS (Breast Imaging Reporting and Data System) e o tipo de lesão. As medidas de DF (DF contorno e DF área) foram calculadas através da aplicação do método box-counting, diretamente em imagens de lesões segmentadas e após a aplicação de um algoritmo de dilatação/erosão. A última medida baseia-se na diferença normalizada entre as duas medidas DF de área antes e após a aplicação do algoritmo de dilatação/erosão. Os resultados demonstram que a medida DF de contorno é uma ferramenta útil na diferenciação de lesões, de acordo com a escala BIRADS e o tipo de lesão; no entanto, em algumas situações, ocorrem alguns erros. O uso combinado desta medida com as quatro medidas propostas pode melhorar a classificação das lesões.

The telegraph as an omen of the future in James W. Carey's vision

In the history of modern communication, after the development of the printing press, the telegraph unleashed a revolution in communications. Today, Internet is in many ways its heir. Reflections on the telegraph may open up perspectives concerning tendencies, possibilities and pitfalls of the Internet. The telegraph has been well explored in important literature on communication and media which tends to emphasize the history of this technology, its social context and institutional meaning [e.g. Robert L. Thompson, 1947, Tom Standage, 2007 [1998]. James W. Carey, the North- American critical cultural studies' mentor, in his essay "Technology and Ideology. The Case of the Telegraph" (2009 [1983]), suggests a distinctive approach. In the telegraph, Carey sees the prototype of many subsequent commercial empires based on science and technology, a pioneer model for complex business management; an example of interest struggle for the patents control; an inductor of changes both in language and in structures of knowledge; and a promoter of a futurist and utopian thought of information technologies. Having in mind a revolution in communications promoted by the Internet, this paper revisits this seminal essay to explore its great attainment, as well as the problems of this kind of approach which conceives the innovation of the telegraph as a metaphor for all the innovations announcing the modern stage of history and determining still today the major lines of development in modern communication systems.

Simulação de plataformas para dispositivos móveis: infraestrutura de simulação sensorial para android

Projeto para obtenção do grau de Mestre em Engenharia Informática e de Computadores

Transfering data from a server to an Android Mobile application: a case study

Nowadays, due to the incredible grow of the mobile devices market, when we want to implement a client-server applications we must consider mobile devices limitations. In this paper we discuss which can be the more reliable and fast way to exchange information between a server and an Android mobile application. This is an important issue because with a responsive application the user experience is more enjoyable. In this paper we present a study that test and evaluate two data transfer protocols, socket and HTTP, and three data serialization formats (XML, JSON and Protocol Buffers) using different environments and mobile devices to realize which is the most practical and fast to use.

Engineering hybrid wired/wireless fieldbus networks - a case study

Advances in networking and information technologies are transforming factory-floor communication systems into a mainstream activity within industrial automation. It is now recognized that future industrial computer systems will be intimately tied to real-time computing and to communication technologies. For this vision to succeed, complex heterogeneous factory-floor communication networks (including mobile/wireless components) need to function in a predictable, flawless, efficient and interoperable way. In this paper we re-visit the issue of supporting real-time communications in hybrid wired/wireless fieldbus-based networks, bringing into it some experimental results obtained in the framework of the RFieldbus ISEP pilot.

Distributed computer-controlled systems: the DEAR-COTS approach

This paper proposes a new architecture targeting real-time and reliable Distributed Computer-Controlled Systems (DCCS). This architecture provides a structured approach for the integration of soft and/or hard real-time applications with Commercial O -The-Shelf (COTS) components. The Timely Computing Base model is used as the reference model to deal with the heterogeneity of system components with respect to guaranteeing the timeliness of applications. The reliability and availability requirements of hard real-time applications are guaranteed by a software-based fault-tolerance approach.

Supporting real-time distributed computer-controlled systems with multi-hop P-NET networks

Fieldbus communication networks aim to interconnect sensors, actuators and controllers within process control applications. Therefore, they constitute the foundation upon which real-time distributed computer-controlled systems can be implemented. P-NET is a fieldbus communication standard, which uses a virtual token-passing medium-access-control mechanism. In this paper pre-run-time schedulability conditions for supporting real-time traffic with P-NET networks are established. Essentially, formulae to evaluate the upper bound of the end-to-end communication delay in P-NET messages are provided. Using this upper bound, a feasibility test is then provided to check the timing requirements for accessing remote process variables. This paper also shows how P-NET network segmentation can significantly reduce the end-to-end communication delays for messages with stringent timing requirements.

An architecture for reliable distributed computer-controlled systems

In Distributed Computer-Controlled Systems (DCCS), both real-time and reliability requirements are of major concern. Architectures for DCCS must be designed considering the integration of processing nodes and the underlying communication infrastructure. Such integration must be provided by appropriate software support services. In this paper, an architecture for DCCS is presented, its structure is outlined, and the services provided by the support software are presented. These are considered in order to guarantee the real-time and reliability requirements placed by current and future systems.

A communication support for real-time distributed computer controlled systems

In this paper, we analyse the ability of P-NET [1] fieldbus to cope with the timing requirements of a Distributed Computer Control System (DCCS), where messages associated to discrete events should be made available within a maximum bound time. The main objective of this work is to analyse how the network access and queueing delays, imposed by P-NET’s virtual token Medium Access Control (MAC) mechanism, affect the realtime behaviour of the supported DCCS.

Vision antropologica de la descentralizacion del sistema de salud en Mexico

OBJETIVO: Analizar cambios organizacionales, políticos y económicos resultantes de la descentralización del sistema de salud en la población sin seguridad social en México. METODOS: Se visitaron tres estados del país seleccionados por el número de habitantes en condición de pobreza, el partido político en el poder y la etapa de implementación de la descentralización (la primera fue en 1984 y la segunda en 1997). Se realizaron entrevistas durante 2007 con informantes clave de los servicios de salud de los gobiernos estatales, personas que acudieron a consulta en los servicios estatales de salud y líderes comunitarios. Los datos fueron analizados desde una perspectiva antropológica y económica. RESULTADOS: La descentralización ocurrió de forma heterogénea en cada estado, observándose una transferencia de responsabilidades de la federación a los estados, más no así una ruptura con la dependencia del nivel central - federal. Las reformas impulsadas desde el nivel federal para crear un esquema fundamentado en principios de subsidiaridad financiera y democratización en salud enfrentan retos políticos y organizacionales para su consolidación. CONCLUSIONES: El enfoque antropológico muestra la relevancia de considerar factores organizacionales, políticos y económicos como parte del proceso de descentralización.

A vision of cyber-physical internet

When the Internet was born, the purpose was to interconnect computers to share digital data at large-scale. On the other hand, when embedded systems were born, the objective was to control system components under real-time constraints through sensing devices, typically at small to medium scales. With the great evolution of the Information and Communication Technology (ICT), the tendency is to enable ubiquitous and pervasive computing to control everything (physical processes and physical objects) anytime and at a large-scale. This new vision gave recently rise to the paradigm of Cyber-Physical Systems (CPS). In this position paper, we provide a realistic vision to the concept of the Cyber-Physical Internet (CPI), discuss its design requirements and present the limitations of the current networking abstractions to fulfill these requirements. We also debate whether it is more productive to adopt a system integration approach or a radical design approach for building large-scale CPS. Finally, we present a sample of realtime challenges that must be considered in the design of the Cyber-Physical Internet.

Using a prioritized MAC protocol to execute the database operation join in networked embedded computer systems

Database query languages on relations (for example SQL) make it possible to join two relations. This operation is very common in desktop/server database systems but unfortunately query processing systems in networked embedded computer systems currently do not support this operation; specifically, the query processing systems TAG, TinyDB, Cougar do not support this. We show how a prioritized medium access control (MAC) protocol can be used to efficiently execute the database operation join for networked embedded computer systems where all computer nodes are in a single broadcast domain.

Evaluating Android OS for embedded real-time systems

Since its official public release, Android has captured the interest from companies, developers and the general audience. From that time up to now, this software platform has been constantly improved either in terms of features or supported hardware and, at the same time, extended to new types of devices different from the originally intended mobile ones. However, there is a feature that has not been explored yet - its real-time capabilities. This paper intends to explore this gap and provide a basis for discussion on the suitability of Android in order to be used in Open Real-Time environments. By analysing the software platform, with the main focus on the virtual machine and its underlying operating system environments, we are able to point out its current limitations and, therefore, provide a hint on different perspectives of directions in order to make Android suitable for these environments. It is our position that Android may provide a suitable architecture for real-time embedded systems, but the real-time community should address its limitations in a joint effort at all of the platform layers.

Human-Human Collaboration in Virtual Teams

Extended and networked enterprises distribute the design of products, planning of the production process, and manufacturing regionally if not globally. Employees are therefore confronted with collaborative work over remote sites. A cost effective collaboration depends highly on the organization maintaining a common understanding for this kind of work and a suitable support with information and communication technology. The usual face to face work is going to be replaced at least partly if not totally by computer mediated collaboration. Creating and maintaining virtual teams is a challenge to work conditions as well as technology. New developments on cost-effective connections are providing not only vision and auditory perception but also haptic perception. Research results for improving remote collaboration are presented. Individual, social and cultural aspects are considered as new requirements on the employees of networked and extended enterprises.

Asthenopic symptoms and binocular vision of professional users of optical microscope

Desde 1935 que tem sido demonstrada a relação entre a execução de um trabalho de perto prolongado e o aparecimento de queixas visuais astenópicas. Anomalias da VB encontram-se significativamente aumentadas ao fim de um dia de trabalho com fixação de perto. Diminuição significativa da amplitude de acomodação e convergência depois de quatro dias a realizar uma atividade de perto. Objectivo geral: avaliar o estado da visão binocular dos profissionais de Anatomia Patológica utilizadores de microscópio ótico. Objectivos específicos: identificar as queixas astenópicas mais frequentes dos profissionais durante o trabalho com o microscópio ótico; comparar o estado da VB no início e no final de uma semana de trabalho; correlacionar o estado da VB com as queixas astenópicas sentidas pelos profissionais; correlacionar as queixas astenópicas com as horas e o número de anos de trabalho com o microscópio.