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Publications

Publications by CSE

2020

Providing Secured Access Delegation in Identity Management Systems

Authors
Shehu, AS; Pinto, A; Correia, ME;

Publication
PROCEEDINGS OF THE 17TH INTERNATIONAL JOINT CONFERENCE ON E-BUSINESS AND TELECOMMUNICATIONS (SECRYPT), VOL 1

Abstract
The evolutionary growth of information technology has enabled us with platforms that eases access to a wide range of electronic services. Typically, access to these services requires users to authenticate their identity, which involves the release, dissemination and processing of personal data by third parties such as service and identity providers. The involvement of these and other entities in managing and processing personal identifiable data has continued to raise concerns on privacy of personal information. Identity management systems (IdMs) emerged as a promising solution to address major access control and privacy issues, however most research works are focused on securing service providers (SPs) and the services provided, with little emphases on users privacy. In order to optimise users privacy and ensure that personal information are used only for intended purposes, there is need for authorisation systems that controls who may access what and under what conditions. However, for adoption data owners perspective must not be neglected. To address these issues, this paper introduces the concept of IdM and access control framework which operates with RESTful based services. The proposal provides a new level of abstraction and logic in access management, while giving data owner a decisive control over access to personal data using smartphone. The framework utilises Attribute based access control (ABAC) method to authenticate and authorise users, Open ID Connect (OIDC) protocol for data owner authorisation and Public-key cryptography to achieve perfect forward secrecy communication. The solution enables data owner to attain the responsibility of granting or denying access to their data, from a secured communication with an identity provider using a digitally signed token.

2019

Minha: Large-Scale Distributed Systems Testing Made Practical

Authors
Machado, N; Maia, F; Neves, F; Coelho, F; Pereira, J;

Publication
23rd International Conference on Principles of Distributed Systems, OPODIS 2019, December 17-19, 2019, Neuchâtel, Switzerland.

Abstract
Testing large-scale distributed system software is still far from practical as the sheer scale needed and the inherent non-determinism make it very expensive to deploy and use realistically large environments, even with cloud computing and state-of-the-art automation. Moreover, observing global states without disturbing the system under test is itself difficult. This is particularly troubling as the gap between distributed algorithms and their implementations can easily introduce subtle bugs that are disclosed only with suitably large scale tests. We address this challenge with Minha, a framework that virtualizes multiple JVM instances in a single JVM, thus simulating a distributed environment where each host runs on a separate machine, accessing dedicated network and CPU resources. The key contributions are the ability to run off-the-shelf concurrent and distributed JVM bytecode programs while at the same time scaling up to thousands of virtual nodes; and enabling global observation within standard software testing frameworks. Our experiments with two distributed systems show the usefulness of Minha in disclosing errors, evaluating global properties, and in scaling tests orders of magnitude with the same hardware resources. © Nuno Machado, Francisco Maia, Francisco Neves, Fábio Coelho, and José Pereira; licensed under Creative Commons License CC-BY 23rd International Conference on Principles of Distributed Systems (OPODIS 2019).

2019

Age and level of education impact on expectancy and perceived similarity between virtual and real touristic environments

Authors
Magalhaes, M; Melo, M; Coelho, A; Bessa, M;

Publication
PROCEEDINGS OF THE 2019 INTERNATIONAL CONFERENCE ON GRAPHICS AND INTERACTION (ICGI 2019)

Abstract
This paper focuses on the combination of 360-degree video and virtual reality for improving the touristic experience. Three scenarios were considered in this study: two 360-degree video visualizations, each one related to different touristic places, both presented in an immersive way, followed by an actual visit to those places. By comparing these situations, it was intended to determine the degree of perceived similarity between the virtual and the corresponding real sites, and to analyze if the users' expectancy was fulfilled. This research comprised a qualitative analysis using data collection based on questionnaires, which were applied to a sample consisted of 45 participants. The independent variables of the study were the participants' age and level of education. The results show no statistically significant impact between the two independent variables (users' age and level of education) and perceived similarity and users' expectancy. Our findings suggest that virtual tourism can act as an efficient promotion tool, considering that users' perceived destination image is not compromised regarding their age or level of education.

2019

Providing industry 4.0 technologies: The case of a production technology cluster

Authors
Dalmarco, G; Ramalho, FR; Barros, AC; Soares, AL;

Publication
Journal of High Technology Management Research

Abstract
The concept of industry 4.0 (i4.0) encompasses the integration of different technologies into an autonomous, knowledge- and sensor-based, self-regulating production system. Our objective is to synthesize which are the challenges and opportunities of adopting i4.0 from the perspective of technology provider companies. A single-case research was conducted with ten companies at the Portuguese Production Technologies Cluster. Based on i4.0 technologies – Augmented reality; Additive Manufacturing; Big Data; Cloud Computing; Cyber-Physical Systems; Cybersecurity; Smart Robotics; Simulation; and System Integration – interviewees mentioned that the main adoption challenges are the analysis of data generated, integration of new technologies with available equipment and workforce, and computational limitations. The main opportunities are improvements in: efficiency; flexibility; productivity; cybersecurity; quality of products and services; and decision process due to data analysis. Interviewees have also foreseen changes in company's business model through the integration of internal resources with complementary activities of their partners and other cluster companies. © 2019 Elsevier Inc.

2019

Correlation between Game Experience and Presence in immersive virtual reality games

Authors
Goncalves, G; Coelho, H; Monteiro, P; Melo, M; Bessa, M;

Publication
PROCEEDINGS OF THE 2019 INTERNATIONAL CONFERENCE ON GRAPHICS AND INTERACTION (ICGI 2019)

Abstract
Virtual Reality (VR) technologies have evolved to the point where it is being used in various areas (entertainment, medicine, education, etc.). One of the metrics that allow the evaluation of the virtual experience is Presence. In this work, we conduct an exploratory study that studies which factors of VR games correlate to presence. Various components of games are also shared between other VR applications allowing the results to be applicable not only in VR games. A study with 78 participants divided into 5 groups was conducted where each group played a different VR game. Presence and Game Experience were evaluated. The results indicated multiple positive correlations between subscales of Presence and Game Experience.

2019

Anomaly Detection in Sequential Data: Principles and Case Studies

Authors
Andrade, T; Gama, J; Ribeiro, RP; Sousa, W; Carvalho, A;

Publication
Wiley Encyclopedia of Electrical and Electronics Engineering

Abstract

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