Pressure-Frequency Sensing Subxiphoid Access System for Use in Percutaneous Cardiac Electrophysiology: Prototype Design and Pilot Study Results

We have designed, built, and tested an early prototype of a novel subxiphoid access system intended to facilitate epicardial electrophysiology, but with possible applications elsewhere in the body. The present version of the system consists of a commercially available insertion needle, a miniature pressure sensor and interconnect tubing, read-out electronics to monitor the pressures measured during the access procedure, and a host computer with user-interface software. The nominal resolution of the system is <0.1 mmHg, and it has deviations from linearity of <1%. During a pilot series of human clinical studies with this system, as well as in an auxiliary study done with an independent method, we observed that the pericardial space contained pressure-frequency components related to both the heart rate and respiratory rate, while the thorax contained components related only to the respiratory rate, a previously unobserved finding that could facilitate access to the pericardial space. We present and discuss the design principles, details of construction, and performance characteristics of this system.

A framework for table driven testing of Java classes

With the advent of object-oriented languages and the portability of Java, the development and use of class libraries has become widespread. Effective class reuse depends on class reliability which in turn depends on thorough testing. This paper describes a class testing approach based on modeling each test case with a tuple and then generating large numbers of tuples to thoroughly cover an input space with many interesting combinations of values. The testing approach is supported by the Roast framework for the testing of Java classes. Roast provides automated tuple generation based on boundary values, unit operations that support driver standardization, and test case templates used for code generation. Roast produces thorough, compact test drivers with low development and maintenance cost. The framework and tool support are illustrated on a number of non-trivial classes, including a graphical user interface policy manager. Quantitative results are presented to substantiate the practicality and effectiveness of the approach. Copyright (C) 2002 John Wiley Sons, Ltd.

Infusing the use of seasonal climate forecasting into crop management practice in North East Australia using discussion support software

Seasonal climate forecasting offers potential for improving management of crop production risks in the cropping systems of NE Australia. But how is this capability best connected to management practice? Over the past decade, we have pursued participative systems approaches involving simulation-aided discussion with advisers and decision-makers. This has led to the development of discussion support software as a key vehicle for facilitating infusion of forecasting capability into practice. In this paper, we set out the basis of our approach, its implementation and preliminary evaluation. We outline the development of the discussion support software Whopper Cropper, which was designed for, and in close consultation with, public and private advisers. Whopper Cropper consists of a database of simulation output and a graphical user interface to generate analyses of risks associated with crop management options. The charts produced provide conversation pieces for advisers to use with their farmer clients in relation to the significant decisions they face. An example application, detail of the software development process and an initial survey of user needs are presented. We suggest that discussion support software is about moving beyond traditional notions of supply-driven decision support systems. Discussion support software is largely demand-driven and can compliment participatory action research programs by providing cost-effective general delivery of simulation-aided discussions about relevant management actions. The critical role of farm management advisers and dialogue among key players is highlighted. We argue that the discussion support concept, as exemplified by the software tool Whopper Cropper and the group processes surrounding it, provides an effective means to infuse innovations, like seasonal climate forecasting, into farming practice. Crown Copyright (C) 2002 Published by Elsevier Science Ltd. All rights reserved.

SHACC: a functional prototyper for a component calculus

Over the last decade component-based software development arose as a promising paradigm to deal with the ever increasing complexity in software design, evolution and reuse. SHACC is a prototyping tool for component-based systems in which components are modelled coinductively as generalized Mealy machines. The prototype is built as a HASKELL library endowed with a graphical user interface developed in Swing

A Methodology for GUI Layer Redefinition Through Virtualization and Computer Vision

Nowadays despite improvements in usability and intuitiveness users have to adapt to the proposed systems to satisfy their needs. For instance, they must learn how to achieve tasks, how to interact with the system, and fulfill system's specifications. This paper proposes an approach to improve this situation enabling graphical user interface redefinition through virtualization and computer vision with the aim of increasing the system's usability. To achieve this goal the approach is based on enriched task models, virtualization and picture-driven computing.

Towards a Catalog of Usability Smells

This paper presents a catalog of smells in the context of interactive applications. These so-called usability smells are indicators of poor design on an application’s user interface, with the potential to hinder not only its usability but also its maintenance and evolution. To eliminate such usability smells we discuss a set of program/usability refactorings. In order to validate the presented usability smells catalog, and the associated refactorings, we present a preliminary empirical study with software developers in the context of a real open source hospital management application. Moreover, a tool that computes graphical user interface behavior models, giving the applications’ source code, is used to automatically detect usability smells at the model level.

Sensor de glicose polarimétrico

Esta tese tem como principal objectivo a investigação teórica e experimental do desempenho de um sensor polarimétrico baseado num cristal líquido para medição da concentração de glicose. Recentemente uma série de sensores polarimétricos baseados em cristais líquidos foram propostos na literatura e receberam considerável interesse devido as suas características únicas. De facto, em comparação com outros moduladores electro-ópticos, o cristal líquido funciona com tensões mais baixas, tem baixo consumo de energia e maior ângulo de rotação. Além disso, este tipo de polarímetro pode ter pequenas dimensões que é uma característica interessante para dispositivos portáteis e compactos. Existem por outro lado algumas desvantagens, nomeadamente o facto do desempenho do polarímetro ser fortemente dependente do tipo de cristal líquido e da tensão a ele aplicada o que coloca desafios na escolha dos parâmetros óptimos de operação. Esta tese descreve o desenvolvimento do sensor polarimétrico, incluindo a integração dos componentes de óptica e electrónica, os algoritmos de processamento de sinal e um interface gráfico que facilita a programação de diversos parâmetros de operação e a calibração do sensor. Após a optimização dos parâmetros de operação verificou-se que o dispositivo mede a concentração da glicose em amostras com uma concentração de 8 mg/ml, com uma percentagem de erro inferior a 6% e um desvio padrão de 0,008o. Os resultados foram obtidos para uma amostra com percurso óptico de apenas 1 cm.

MASCEM improvement for agent based coalitions

This paper presents MASCEM - Multi-Agent Simulator for Electricity Markets improvement towards an enlarged model for Seller Agents coalitions. The simulator has been improved, both regarding its user interface and internal structure. The OOA, used as development platform, version was updated and the multi-agent model was adjusted for implementing and testing several negotiations regarding Seller agents’ coalitions. Seller coalitions are a very important subject regarding the increased relevance of Distributed Generation under liberalised electricity markets.

Bancada didáctica para simulação de uma Unidade de Microgeração

Neste trabalho é desenvolvida uma bancada didáctica que permite simular o funcionamento de um sistema de microgeração. A bancada inclui uma máquina síncrona responsável pela geração de energia eléctrica acoplada a uma máquina de indução que simula a máquina primária. A máquina de indução é controlada por um sistema electrónico de controlo de potência (variador de velocidade) que permite manter constante a velocidade de rotação e consequentemente a frequência da tensão gerada pela máquina síncrona. Por sua vez, a excitação da máquina síncrona é controla por uma fonte de tensão externa. A parametrização e controlo do variador de velocidade, assim como o controlo da fonte de tensão externa, são feitos a partir dum software que corre num PC, que também monitoriza a tensão gerada pela máquina síncrona. Este software é ainda responsável pela interface com o utilizador. O software desenvolvido permite manter as características da tensão gerada pela máquina síncrona independentemente da carga imposta.

Modelos e interfaces gráficos para objectos de aprendizagem na área da saúde

A educação é uma área bastante importante no desenvolvimento humano e tem vindo a adaptar-se às novas tecnologias. Tentam-se encontrar novas maneiras de ensinar de modo a obter um rendimento cada vez maior na aprendizagem das pessoas. Com o aparecimento de novas tecnologias como os computadores e a Internet, a concepção de aplicações digitais educativas cresceu e a necessidade de instruir cada vez melhor os alunos leva a que estas aplicações precisem de um interface que consiga leccionar de uma maneira rápida e eficiente. A combinação entre o ensino com o auxílio dessas novas tecnologias e a educação à distância deu origem ao e-Learning (ensino à distância). Através do ensino à distância, as possibilidades de aumento de conhecimento dos alunos aumentaram e a informação necessária tornou-se disponível a qualquer hora em qualquer lugar com acesso à Internet. Mas os cursos criados online tinham custos altos e levavam muito tempo a preparar o que gerou um problema para quem os criava. Para recuperar o investimento realizado decidiu-se dividir os conteúdos em módulos capazes de serem reaproveitados em diferentes contextos e diferentes tipos de utilizadores. Estes conteúdos modulares foram denominados Objectos de Aprendizagem. Nesta tese, é abordado o estudo dos Objectos de Aprendizagem e a sua evolução ao longo dos tempos em termos de interface com o utilizador. A concepção de um interface que seja natural e simples de utilizar nem sempre é fácil e independentemente do contexto em que se insere, requer algum conhecimento de regras que façam com que o utilizador que use determinada aplicação consiga trabalhar com um mínimo de desempenho. Na concepção de Objectos de Aprendizagem, áreas de complexidade elevada como a Medicina levam a que professores ou doutores sintam alguma dificuldade em criar um interface com conteúdos educativos capaz de ensinar com eficiência os alunos, devido ao facto de grande parte deles desconhecerem as técnicas e regras que levam ao desenvolvimento de um interface de uma aplicação. Através do estudo dessas regras e estilos de interacção torna-se mais fácil a criação de um bom interface e ao longo desta tese será estudado e proposto uma ferramenta que ajude tanto na criação de Objectos de Aprendizagem como na concepção do respectivo interface.

Negotiation platform for personalised advertising

This paper describes a multi-agent brokerage platform for near real time advertising personalisation organised in three layers: user interface, agency and marketplace. The personalisation is based on the classification of viewer profiles and advertisements (ads). The goal is to provide viewers with a personalised advertising alignment during programme intervals. The enterprise interface agents upload new ads and negotiation profiles to producer agents and new user and negotiation profiles to distributor agents. The agency layer is composed of agents that represent ad producer and media distributor enterprises as well as the market regulator. The enterprise agents offer data upload and download operations as Web Services and register the specification of these interfaces at an UDDI registry for future discovery. The market agent supports the registration and deregistration of enterprise delegate agents at the marketplace. This paper addresses the marketplace layer, an agent-based negotiation platform per se, where delegates of the relevant advertising agencies and programme distributors negotiate to create the advertising alignment that best fits a viewer profile and the advertising campaigns available. The whole brokerage platform is being developed in JADE, a multi-agent development platform. The delegate agents download the negotiation profile and upload the negotiation results from / to the corresponding enterprise agent. In the meanwhile, they negotiate using the Iterated Contract Net protocol. All tools and technologies used are open source.

Modellus: Learning Physics with Mathematical Modelling

Tese de doutoramento em Ciências da Educação, área de Teoria Curricular e Ensino das Ciências

Interactive light and sound table: an EPS@ISEP project

Interactive products are appealing objects in a technology-driven society and the offer in the market is wide and varied. Most of the existing interactive products only provide either light or sound experiences. Therefore, the goal of this project was to develop a product aimed for children combining both features. This project was developed by a team of four thirdyear students with different engineering backgrounds and nationalities during the European Project Semester at ISEP (EPS@ISEP) in 2012. This paper presents the process that led to the development of an interactive sound table that combines nine identical interaction blocks, a control block and a sound block. Each interaction block works independently and is composed of four light emitting diodes (LED) and one infrared (IR) sensor. The control is performed by an Arduino microcontroller and the sound block includes a music shield and a pair of loud speakers. A number of tests were carried out to assess whether the controller, IR sensors, LED, music shield and speakers work together properly and if the ensemble was a viable interactive light and sound device for children.

Multifunctional controller architecture for sold-state marx modulator based on FPGA

This paper proposes a multifunctional architecture to implement field-programmable gate array (FPGA) controllers for power converters and presents a prototype for a pulsed power generator based on a solid-state Marx topology. The massively parallel nature of reconfigurable hardware platforms provides very high processing power and fast response times allowing the implementation of many subsystems in the same device. The prototype includes the controller, a failure detection system, an interface with a safety/emergency subsystem, a graphical user interface, and a virtual oscilloscope to visualize the generated pulse waveforms, using a single FPGA. The proposed architecture employs a modular design that can be easily adapted to other power converter topologies.

Design of an extensible metadata editor based on RDF

The content of a Learning Object is frequently characterized by metadata from several standards, such as LOM, SCORM and QTI. Specialized domains require new application profiles that further complicate the task of editing the metadata of learning object since their data models are not supported by existing authoring tools. To cope with this problem we designed a metadata editor supporting multiple metadata languages, each with its own data model. It is assumed that the supported languages have an XML binding and we use RDF to create a common metadata representation, independent from the syntax of each metadata languages. The combined data model supported by the editor is defined as an ontology. Thus, the process of extending the editor to support a new metadata language is twofold: firstly, the conversion from the XML binding of the metadata language to RDF and vice-versa; secondly, the extension of the ontology to cover the new metadata model. In this paper we describe the general architecture of the editor, we explain how a typical metadata language for learning objects is represented as an ontology, and how this formalization captures all the data required to generate the graphical user interface of the editor.