Cookies Policy
The website need some cookies and similar means to function. If you permit us, we will use those means to collect data on your visits for aggregated statistics to improve our service. Find out More
Accept Reject
  • Menu
Publications

Publications by João Barroso

2013

Problem Conditioning Interpolation Educational Tool

Authors
da Costa, MIT; Soares, S; Cardeal, S; Barroso, J;

Publication
2013 IEEE GLOBAL ENGINEERING EDUCATION CONFERENCE (EDUCON)

Abstract
This paper presents an educational tool to be used in signal processing interpolation-related subjects. Besides the consolidation of acquired theoretical knowledge, the tool allows its users to apply three error patterns geometry to the signals and test minimum dimension and maximum dimension signal reconstruction algorithms. In the specific case of minimum dimension problems it can be solved using different solvers, iterative and direct linear equations methods. The developed tool allows the problem conditioning analysis through the spectral radius of the system matrix, the condition number and others parameters available in some specific methods. This feature gives the possibility to alter the problem definitions to the desired goal before the reconstruction begins and to choose the optimal method, depending on each problem constraints The time unit that measures the algorithms performance is expressed in terms of one Fourier Transform (FFT) calculation time. In this way the data is presented not in an absolute way but in a relative measure independent from the machine's architecture.

2013

Supporting Accessibility in Higher Education Information Systems

Authors
Reis, A; Barroso, J; Gonçalves, R;

Publication
Universal Access in Human-Computer Interaction. Applications and Services for Quality of Life - 7th International Conference, UAHCI 2013, Held as Part of HCI International 2013, Las Vegas, NV, USA, July 21-26, 2013, Proceedings, Part III

Abstract
Higher education institutions (HEI) and students are highly dependent of information systems, implemented as web applications. Students must be able to access this applications, thought accessible web interfaces, in order to perform their academic activities. This paper presents an overview of a typical set of web applications used by students and the main concerns regarding accessibility compliance. The analysis was conducted using the systems at the University of Trás-os-Montes e Alto Douro. © 2013 Springer-Verlag Berlin Heidelberg.

2017

Supporting Accessibility in Higher Education Information Systems: A 2016 Update

Authors
Reis, A; Martins, P; Borges, J; Sousa, A; Rocha, T; Barroso, J;

Publication
UNIVERSAL ACCESS IN HUMAN-COMPUTER INTERACTION: DESIGN AND DEVELOPMENT APPROACHES AND METHODS, PT I

Abstract
Higher Education Institutions (HEIs) have come a long way on the usage of Information Systems (IS) at the several phases of the execution of their business plan. These organizations are very peculiar in the sense that most of the IS technologies have been developed as a consequence of the research work of the HEIs, positioning them as creators and as consumers of IS technologies. In fact, a considerable part of the IS products, currently available for the education sector, was initially created in a HEI as an in-house development. For these reason, the adoption of IS technologies by HEIs has followed two distinct paths: the in-house creation, previously described; and a current market adoption, similarly to most other companies IS adoption. Up to 2013 the IS applications for HEIs was mostly provided as web applications running on the HEI local datacenters and devoted to some specific phases of the HEI business plan. Currently, in 2016, this scenario has evolved in two ways: (i) to a wider range of type of applications, including: the old type of web application; new mobile applications; and new web application, running on the cloud and used as a service, (ii) to a more extended support coverage regarding the HEI business model phases, i.e., there are more IS applications supporting more aspects of the HEIs’ activities. In 2013, it was published a study regarding the accessibility support in HEI IS applications and related user practices. Due to the advances in IS technologies and their adoption by HEIs, it is now time to update this perspective on accessibility and HEIs IS, in order to assess how the progresses on IS applications used in HEIs have dealt with the accessibility concerns. The study updates the IS accessibility features as well as the new systems and new types of systems currently in use. © Springer International Publishing AG 2017.

2014

Traffic Management in Rural Networks

Authors
Emiliano, R; Silva, F; Frazao, L; Barroso, J; Pereira, A;

Publication
DESIGN, USER EXPERIENCE, AND USABILITY: USER EXPERIENCE DESIGN FOR EVERYDAY LIFE APPLICATIONS AND SERVICES, PT III

Abstract
The internet is increasingly present in people's lives, being used in diverse tasks, such as checking e-mail up to online gaming and streaming. The so-called "killer applications" are applications that, when not properly identified and prevented, have more impact on the network, making it slow. When these applications are used on networks with limited resources, as happens in rural networks, they cause a large load on the network, making it difficult its use for work purposes. It is important then to recognize and characterize this traffic to take action so that it does not cause network problems. With that in mind, the work presented in this paper describes the research and identification of cost free traffic analysis solutions that can help to overcome such problems. For that, we perform preliminary testing and a performance comparison of those tools, focusing on testing particular types of network traffic. After that, we describe the analysis and subsequent modification of the source code for storing important traffic data for the tests, as well as the test scenarios in laboratory and reallife environments. These tasks are aimed on collecting information that assists in taking action to improve the allocation of network resources to priority traffic.

2013

Web accessibility - From the evaluation and analysis to the implementation - The anoGov/PEPPOL case

Authors
Goncalves, R; Martins, J; Branco, F; Barroso, J;

Publication
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)

Abstract
The XXI Century society has developed a drive for Information and the Web, as one of the extremely important technologies of our times, represents the main channel to access it. As a result of this, one can perceive that the Web, and the inherent websites, must be accessible to all, in order to maintain the imperative social equality. Despite the legal requirements to the Portuguese Web content accessibility levels, in effect since 1999, the existent studies that focused on assessing those same levels of accessibility reported that the Portuguese websites, in their majority, were not compliant with the existent standards. In mid-2007 we started, within our research group and in partnership with both UMIC - Knowledge Society Agency and APDSI - Association for the Promotion and Development of the Information Society, a Web accessibility barometer. The goal of this barometer has been assessing the accessibility levels of the Portuguese websites, creating recommendations - for both the organizations and the civil society - towards the improvement of the referred websites, and publicly presenting the achieved results. One of the Portuguese enterprises that is adopting the accessibility standards into its public procurement platform anoGov is ANO. This company established a research project alongside UTAD University in order to achieve technical know-how and good practices that allowed them to develop accessible and usable Web content. © 2013 Springer-Verlag Berlin Heidelberg.

2017

Web application for the training of the correct pronunciation of words in Portuguese for people with speech and language disorders - preliminary usability study

Authors
Rocha, T; Marques, A; Brito, JP; Cardoso, L; Martins, P; Barroso, J;

Publication
2017 12TH IBERIAN CONFERENCE ON INFORMATION SYSTEMS AND TECHNOLOGIES (CISTI)

Abstract
In this paper, a Web application that allows people with speech impairments to train and amend pronunciation of words by repeating words presented in a interface with visual and auditory stimuli, is presented. With this app, we aim at present a training assistive tool to be used by the user, in a daily situation, where the main asset is the feedback about the rate of correct pronunciation, thus allowing users to train, autonomously, at home. Additionally, we present a preliminary user study to assess usability of the proposed application. For that, we invited a group of people with speech impairments to perform training tasks with the application. In the assessment, we register the following parameters: effectiveness (successful conclusion of the training tasks and percentage of pronouncing success); efficiency (number of errors made, number and type of difficulties found); and, satisfaction (the acceptance and comfort to complete the training tasks). Overall, the preliminary results showed that participants achieved an efficiency rate of 53.4% in the accomplishment of the proposed tasks. On average, for each image, participants missed at least 2 times, where the most registered difficulty was the pronunciation of words with accents. Regarding satisfaction, we noticed that they like it as they ask not only to repeat the test but also the addition of more pictures to perform more tests with the proposed web application.

  • 8
  • 41