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Publications

Publications by Rui Pedro Rodrigues

2016

Adaptation and Validation of the Igroup Presence Questionnaire (IPQ) in a Portuguese Sample

Authors
Vasconcelos Raposo, J; Bessa, M; Melo, M; Barbosa, L; Rodrigues, R; Teixeira, CM; Cabral, L; Sousa, AA;

Publication
PRESENCE-TELEOPERATORS AND VIRTUAL ENVIRONMENTS

Abstract
The present study aims (a) to translate and adapt the Igroup Presence Questionnaire (IPQ) to the Portuguese context (semantic equivalence/ conceptual and content validity) and (b) to examine its psychometric properties (reliability and factorial validity). The sample consisted of 478 subjects (285 males and 193 females). The fidelity of the factors varied between 0.53 and 0.83. The confirmatory factor analysis results produced a 14-item version of IPQ-PT, accepting covariance between residual errors of some items of the instrument, as the best structural representation of the data analyzed. The CFA was conducted based on a three-variable model. The fit indexes obtained were X-2/df = 2.647, GFI = .948, CFI = .941, RSMEA = .059, and AIC = 254. These values demonstrate that the proposed Portuguese translation of the IPQ maintains its original validity, demonstrating it to be a robust questionnaire to measure the sense of presence in virtual reality studies. It is therefore recommended for use in presence research when using Portuguese samples.

2015

An Integrated Framework for Mobile-Based ADAS Simulation

Authors
Goncalves, JSV; Jacob, J; Rossetti, RJF; Coelho, A; Rodrigues, R;

Publication
MODELING MOBILITY WITH OPEN DATA

Abstract
The increasing number of vehicles and mobile users has led to a huge increase in the development of Advanced Driver Assistance Systems (ADAS). In this paper we propose a multi-agent-based driving simulator which integrates a testbed that allows ADAS developers to compress testing time and carry out tests in a controlled environment while using a low-cost setup. We use the SUMO microscopic simulator and a serious-game-based driving simulator which has geodata provided from standard open sources. This simulator connects to an Android device and sends data such as the current GPS coordinates and transportation network data. One important feature of this application is that it allows ADAS validation without the need of field testing. Also important is the suitability of our architecture to serve as an appropriate means to conduct behaviour elicitation through peer-designed agents, as well as to collect performance measures related to drivers' interaction with ADAS solutions.

2015

Cities in citizens' hands

Authors
Morgado, L; Rodrigues, R; Coelho, A; Magano, O; Calcada, T; Cunha, PT; Echave, C; Kordas, O; Sama, S; Oliver, J; Ang, J; Deravi, F; Bento, R; Ramos, L;

Publication
PROCEEDINGS OF THE 6TH INTERNATIONAL CONFERENCE ON SOFTWARE DEVELOPMENT AND TECHNOLOGIES FOR ENHANCING ACCESSIBILITY AND FIGHTING INFO-EXCLUSION

Abstract
We propose a new paradigm for public participation in urban planning, a field which presents significant challenges for public understanding and participation. Our approach is based on leveraging the rich diversity of meaning associated with cultural gestures, traditions, folklore, and rituals, and using them in augmented reality systems, in order for citizens' to explore, understand, and communicate the complex, systemic ideas and concepts associated with urban planning. At an immediate level, this approach holds the potential for enabling increased public awareness of what is at stake in urban planning - both on the part of citizens and on the part of public officials, policy-makers, and decision-makers - and consequently enhancing understanding and improving participation in public life and citizenship. It may also open up a new field of research and development in human-computer interaction, to leverage the richness of meaning and modes of expression which exist in various cultures and societies, rather than ignoring them and imposing dumbed-down or prescribed command methods. Thus, it aims to facilitate new levels of empowerment of users in the use of digital systems and data. The active utilization of cultural meaning in gestures, rituals, and social practices may also support and promote better inclusion and participation of minority groups and migrant communities in contemporary, technology-rich life. (c) 2015 The Authors. Published by Elsevier B.V.

2015

Modelling human emotion in interactive environments: Physiological ensemble and grounded approaches for synthetic agents

Authors
Nogueira, PA; Rodrigues, R; Oliveira, E; Nacke, LE;

Publication
Web Intelligence

Abstract
With the rising research in emotionally believable agents, several advances in agent technology have been made, ranging from interactive virtual agents to emotional mechanism simulations and emotional agent architectures. However, creating an emotionally believable agent capable of emotional thought is still largely out of reach. It has been proposed that being able to accurately model human emotion would allow agents to mimic human behaviour while these models are studied to create more accurate theoretical models. In light of these challenges, we present a general method for human emotional state modelling in interactive environments. The proposed method employs a three-layered classification process to model the arousal and valence (i.e., hedonic) emotional components, based on four selected psychophysiological metrics. Additionally, we also developed a simplified version of our system for use in real-time systems and low-fidelity applications. The modelled emotional states by both approaches compared favourably with a manual approach following the current best practices reported in the literature while also improving on its predictive ability. The obtained results indicate we are able to accurately predict human emotional states, both in offline and online scenarios with varying levels of granularity; thus, providing a transversal method for modelling and reproducing human emotional profiles.

2016

Vanishing scares: biofeedback modulation of affective player experiences in a procedural horror game

Authors
Nogueira, PA; Torres, V; Rodrigues, R; Oliveira, E; Nacke, LE;

Publication
JOURNAL ON MULTIMODAL USER INTERFACES

Abstract
To understand the impact of emotionally driven games on player experience, we developed a procedural horror game (Vanish) capable of run-time level, asset, and event generation. Vanish was augmented to interpret players' physiological data as a simplified emotional state, mapping it to a set of adaptation rules that modify the player experience. To explore the effects of adaptation mechanisms on player experience, we conducted a mixed-methods study on three different versions of the game, two of which integrated varying biofeedback mechanisms. Players' affective experiences were objectively measured by analysing physiological data. Additionally, subjective experience was recorded through the use of the Game Experience Questionnaire. Our study confirmed that biofeedback functionality had a statistically significant effect on the ratings of player experience dimensions: immersion, tension, positive affect, and negative affect. Furthermore, participants reported noticeable differences in player experience, favouring the added depth present in the biofeedback-enabled iterations of the game. In the future, these conclusions will help to develop more immersive and engaging player experiences.

2017

Cargo dynamic stability in the container loading problem -a physics simulation tool approach

Authors
Ramos, AG; Jacob, J; Justo, JF; Oliveira, JF; Rodrigues, R; Gomes, AM;

Publication
International Journal of Simulation and Process Modelling

Abstract
The container loading problem (CLP) is a real-world driven, combinatorial optimisation problem that addresses the maximisation of space usage in cargo transport units. The research conducted on this problem failed to fulfill the real needs of the transportation industry, owing to the inadequate representation of practical-relevant constraints. The dynamic stability of cargo is one of the most important practical constraints. It has been addressed in the literature in an over-simplified way which does not translate to real-world stability. This paper proposes a physics simulation tool based on a physics engine, which can be used to translate real-world stability into the CLP. To validate the tool, a set of benchmark tests is proposed and the results obtained with the physics simulation tool are compared to the state-of-the-art simulation engineering software Abaqus Unified FEA. Analytical calculations have been also conducted, and it was also possible to conclude that the tool proposed is a valid alternative. Copyright © 2017 Inderscience Enterprises Ltd.

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