publications

2004

1. Ancient Word Indexing Using Fuzzy Methods.

   Ribeiro, Cláudia S, Gil, João M, Pinto, João Rogério Caldas, and Costa Sousa, João Miguel

   In n Proceedings of the 4th International Workshop on Pattern Recognition in Information Systems 2004,

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   This paper proposes an optical word indexing system based on fuzzy logic for 17th century printed documents. A pre-processing stage assures only interesting word candidates are considered. The main image-space indexing procedure builds fuzzy membership functions from oriented features extracted using Gabor filter banks. It proceeds by comparing this data with candidate word features and assigning each a similarity value. Results on a significant test set found over 85% of all word occurrences with a false positive rate of less than 20%.

2. Ancient Document Recognition Using Fuzzy Methods.

   Ribeiro, Cláudia S, Gil, João M, Pinto, João Rogério Caldas, and Costa Sousa, João Miguel

   In n Proceedings of the 4th International Workshop on Pattern Recognition in Information Systems 2004,

   Abs PDF

   This paper proposes an optical character recognition system based on fuzzy logic for 17th century printed documents. The process consists of two stages: training with collected character image examples and new character image classification. Training builds fuzzy membership functions from aligned oriented features extracted using Gabor filters. These are used in classification to select a most likely character group for new data. A post-processing stage with a proposed modified Levenshtein word distance metric further improves results. A success rate of 88% is achieved on a significant test set.

2005

1. IEEE

   Ancient document recognition Using Fuzzy Methods

   Sousa, J.M.C., Caldas Pinto, J.R., Ribeiro, C.S., and Gil, J.M.

   In The 14th IEEE International Conference on Fuzzy Systems, 2005. FUZZ ’05. 2005,

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   This paper proposes an optical character recognition system based on fuzzy logic for ancient printed documents. The recognition process consists of two stages: training with collected character image examples and classification of new character images. The proposed OCR builds fuzzy membership functions from oriented features extracted using Gabor filter banks. Results on a significant test led to a character recognition success rate of 88%.

2006

1. IJISTA

   Old document recognition using fuzzy methods

   Sousa, JMC, Gil, JM, Ribeiro, CS, and Pinto, JR Caldas

   International Journal of Intelligent Systems Technologies and Applications 2006,

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   This paper proposes an expert system based on fuzzy logic for optical character recognition of old printed documents. These documents can have some problems, such as distortion, poor printing quality, faded and misprinted characters, speckles and smudges. The recognition process consists of two stages: training with character image examples and classification of new character images. The proposed OCR builds fuzzy membership functions from oriented features extracted using Gabor filter banks. The proposed methodology is tested on three different books from the 17th century, written in Portuguese. The fuzzy recogniser presents a very high character recognition success rate, which confirms the advantage of using expert systems in image based decision systems.

2010

1. Lessons learnt in building serious games and virtual worlds for competence development

   Ribeiro, Claudia, Jepp, Pauline, Pereira, João, and Fradinho, Manuel

   In Workshop Experimental Interactive Learning in Industrial Management of the IFIP Working Group 5.7 2010,

2011

1. Springer

   Digital Storytelling for Competence Development

   Santos, Edgar, Ribeiro, Claudia, Fradinho, Manuel, and Pereira, João

   In New Horizons in Web-Based Learning - ICWL 2010 Workshops 2011,

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   The acquisition of complex knowledge and competences raises difficult challenges for the supporting tools within the corporate environment, which digital storytelling presents a potential solution. Traditionally, a driving goal of digital storytelling is the generation of dramatic stories with human significance, but for learning purposes, the need for drama is complemented by the requirement of achieving particular learning outcomes. This paper presents a narrative engine that supports emergent storytelling to support the development of complex competences in the learning domains of project management and innovation. The approach is based on the adaptation on the Fabula model combined with cases representing situated contexts associated to particular competences. These cases are then triggered to influence the unfolding of the story such that a learner encounters dramatic points in the narrative where the associated competences need to be used. In addition to the description of the approach and corresponding narrative engine, an illustration is presented of how the competence “conflict management” influences a story.

2. Springer

   The Use of Integrative Framework to Support the Development of Competences

   Fradinho Oliveira, Manuel, Andersen, Bjorn, Pereira, Joao, Seager, William, and Ribeiro, Claudia

   In Serious Games Development and Applications 2011,

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   In corporate environments, there is a growing interest in deploying more effective solutions in supporting competence development, namely to address the identified need of developing soft-skills (eg: negotiation, leadership) and complex competences (eg: sense-making and cross-cultural communication). The “learning by doing” has gained prominence, in particular when considering the use of serious games as the delivery platform for the educational content. However, the adoption of serious games alone is not a guarantee for effective learning and consequently, the aim of this paper is to present the integrative framework that combines together five key developments in education research, namely Knowledge Ecology, Social Learning Communities, Threshold Concepts, Experience Management and Cognitive Management. Based on the integrative framework, the paper proceeds to present the TARGET componentized platform.

3. Collaborative Negotiated Deliberation Managing Protocol for Emergent Narrative in Educational Environments

   Fernandes, João, Ribeiro, Claudia, and Pereira, João

   In VideoJogos 2011 – Conferência de Ciências e Artes dos Videojogos 2011,

2012

1. ACM

   Using agent-based simulation to understand cooperation in business organizational settings

   Ribeiro, Claudia, Borbinha, José, Tribolet, José, and Pereira, João

   In Proceedings of the Winter Simulation Conference 2012,

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   There is no doubt around the dynamics and uncertainty characterizing organizations and their environments. Consequently, contemporary organizational thinking has evolved to embrace paradigms supported by complexity theory and its principles. Complexity theory involves the study of many actors and their interactions. One of the central topics regarding interaction between self-interested agents is cooperation. Cooperation is crucial for societies and organizations, since it allows the creation of common goods that no single individual could establish alone. However, this situation itself presents a dilemma, because as the creation of these goods requires an individual effort and the result is shared by everyone, there is the temptation to make an individual contribution as little as possible and receive as much of the result as one can. The problem of how can cooperation emerge in a organization of self-interested individuals is one of the central questions addressed by social sciences, game theory, political science and behavioural and evolutionary economics. The study of large number of actors with changing patterns of interaction often gets too difficult for a mathematical solution, therefore other type of solutions need to be used. A primary research tool of complexity theory is computer simulation. The basic underlying function of this tool is to specify how the agents interact, and then observe properties that occur at the level of the whole organization. The simulation of agents and their interactions is known as agent-based modelling (ABM) (Miller and Page 2007). Although agent-based modelling employs simulation, it does not aim to provide an accurate representation of a particular empirical application (Axelrod 1997). Instead, the goal of agent-based modelling is to enrich our understanding of fundamental processes that may appear in a variety of applications. This is the assumptions underlying the proposal described in this paper. To represent the functioning of an organization DEMO’s Ψ-theory (Dietz 2006) was used. The Ψ-theory explains how and why people cooperate and communicate. It postulates that the operation of an organization can be expressed by a specification of the commitments that the organizational subjects enter into and comply with. Based on this theory and concepts developed in Game Theory this paper proposes a agent-based simulation with an underlying conceptual model that allows to experiment and analyse the different patterns that emerge when organizational subjects use different kind of strategies to handle commitments to produce organizational output.

2. A General Process for Developing Business Simulations Games

   Ribeiro, Claudia, Borbinha, José, Pereira, João, and Tribolet, José

   In Proceedings of the 2nd International Conference on Simulation and Modeling Methodologies, Technologies and Applications - SIMULTECH, 2012,

   Abs HTML PDF

   Nowadays people, groups and organizations are increasingly confronted with problems and situations that show an increasing level of complexity. However, human abilities to deal with complex dynamic systems and processes, while behaving in a sustainable way, have not improved to the required extent. One way to deal with complex situation is the simulation approach: build a simplified model of this reality, learn from this simplified model, and, finally, translate the findings or knowledge back to reality. Simulation games are based on this idea. Nevertheless, if we want to make inferences about reality based on experiences and knowledge acquired in a simulation game, we have to be sure that the underlying conceptual model is a good, or valid, representation of the real situation. Based on knowledge gather from the simulation development process and Agent-based Modelling, this paper proposes a general process for developing business simulation games.

3. Elsevier

   iThink: A game-based approach towards improving collaboration and participation in requirement elicitation

   Fernandes, João, Duarte, Diogo, Ribeiro, Claudia, Farinha, Carla, Pereira, João Madeiras, and Silva, Miguel Mira

   Procedia Computer Science 2012,

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   Requirements are the heart of Information Systems development because they determine how the system will operate. There- fore, requirements elicitation is a critical activity of the information systems development life cycle. Recognizing the im- portance of collaborative work and the huge difficulty of gathering stakeholders at the same time and place, researches have been proposing web collaborative tools to elicit requirements. In this article we present a game-based collaborative tool called iThink that aims at improving the participation in a requirement elicitation process. iThink takes advantage of the associa- tion between “gamification” concepts and the six hats of thinking method for collecting both new requirements and feedback about existing ones and for presenting the requirement elicitation process in a form of a collaborative game. Two case-studies, involving several stakeholders, are also presented with the purpose of evaluating the effectiveness and acceptance of this tool.

4. IIM

   Analysing the required properties of business simulation games to be used in e-learning and education

   Blazic, Andrej Jerman, Ribeiro, Claudia, Arh, Tanja, and others,

   Intelligent Information Management 2012,

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   Business simulation games are considered as effective tools for the empowerment and mediation of business content learning. They act as serious games which contribute to learning through a simulation of real-life situations and business environments. They are especially useful in the area of business management processes and business strategies. The blending of designed simulation technology and content curricula offers participants (players, students) a risk-free opportunity to test out a range of relevant strategies to drive business results. By customizing computer-based business simulations, participants can integrate key strategic and financial priorities. This paper provides a brief review of business simulations that serve learning purposes. The first part presents a short introduction and description of business games and their evaluation properties, and the second part provides a brief evaluation and analysis of selected business simulation games.

2013

1. IGI Global

   Challenges of Introducting Serious Games and Virtual Worlds in Educational Curriculum.

   Ribeiro, Claudia, Pereira, João, Calado, C., and Ferreira, C.

   2013,

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2. Springer

   Creating Awareness of Emergency Departments Healthcare Values Using a Serious Game

   Ribeiro, Claudia, Pereira, João, and Borbinha, José

   In Scaling up Learning for Sustained Impact 2013,

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   The world in which medicine and healthcare institutions are managed is rapidly changing in complex and unpredictable ways. In periods of rapid change, highly adaptive organizations have competitive advantage. Therefore, training a modern, adaptive and high performing team is one of the keys to success. There is a growing body of evidence that Game-Based Learning can be highly successful in driving business results, and a variety of drivers are making it harder and harder to ignore as a candidate medium where deep and immersive learning needs to be delivered as is the case of healthcare management. In this paper we describe the Serious Game ImPROVE for training medical workers on the impacts of patient care quality and costs of different configurations of Emergency Department (ED) business processes.

3. IGI Global

   Games in Higher Education: Opportunities, Expectations, Challenges, and Results in Medical Education

   Ribeiro, Cláudia, Monteiro, Micaela, Corredoura, Sofia, Candeias, Fernanda, and Pereira, João

   2013,

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4. IGI Global

   Challenges of Introducting Serious Games and Virtual Worlds in Educational Curriculum.

   Ribeiro, Claudia, Pereira, João, Calado, C., and Ferreira, C.

   2013,

   HTML
5. IEEE

   Serious games in formal medical education: An experimental study

   Ribeiro, Claudia, Antunes, Tiago, Monteiro, Micaela, and Pereira, Joao

   In 2013 5th International Conference on Games and Virtual Worlds for Serious Applications (VS-GAMES) 2013,

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   Medical knowledge has increased exponentially in the last decades. Healthcare professionals face a life- time challenge in medical education right from the beginning of medical school. They experience serious difficulties to keep updated. Traditional adult education, largely used in medical training, shows little effectiveness. Problem-based-learning has been proposed as a student-centred pedagogy to overcome failure of traditional medical instruction. A more recent trend is related to the use of serious games. Although, there are still few examples of serious games for medical education, the increased interest shown in the latest years shows that this is an important area and with a lot of potential to explore. In this paper we present the serious game Critical Transport, targeted at medical students with the aim to teach and train the recommendations for the transport of critically ill patients. This game was designed and validated with physicians of an academic hospital and tested during a formal class.

2014

1. Springer

   Didactical Competence Modeller: Dynamic Story Creation for Serious Games

   Ribeiro, Claudia, Fernandes, João, and Pereira, João

   In New Horizons in Web Based Learning 2014,

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   Traditionally, a driving goal of digital storytelling is the generation of dramatic stories with human significance, but for learning purposes, the need for drama is complemented by the requirement of achieving particular learning outcomes. This paper presents an interactive storytelling conceptual framework that supports the dynamic creation of stories based on predefined pedagogical goals. The approach is based on a hierarchical structure of plot pieces, denominated Narrative Building Blocks which, represent the elements that convey the story context as well as the roles and behaviours of each actor. In addition a case study is described where the concepts presented throughout the paper are applied and exemplified.

2. Springer

   Sepsis Fast Track: A Serious Game for Medical Decision Making

   Ribeiro, Claudia, Monteiro, Micaela, Pereira, João Madeiras, Antunes, Tiago, and Baalsrud Hauge, Jannicke

   In Serious Games Development and Applications 2014,

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   Severe sepsis and sepsis shock are major healthcare problems, affecting millions of people around the world. In order to undermine its potential threat and effect on patients, a medical decision protocol based on evidence was developed to help healthcare professionals to both identify as well as treat these patients in a timely manner. Keeping updated with the algorithm guidelines implies healthcare professionals attending workshop classes, which further complicates the management of resources in an Emergency Department. In this paper we describe the Sepsis Fast Track serious game aimed at teaching healthcare professionals the Sepsis Fast Track guidelines. A set of game mechanics where proposed and developed in order to integrate the guidelines pedagogical goals in the sepsis fast track serious game’s gameplay cycle. A case study was conducted in order to validate if these mechanics are appropriate to both teach and refresh healthcare professionals’ knowledge.

3. Identifying engagement with learning in serious games

   Ribeiro, Claudia, Lavoué, Élise, Sehaba, Karim, Pereira, João, and Hauge, Jannicke Baalsrud

   In 1st Workshop on Learning Analytics for and in serious games (LASG 2014) in conjunction with the 9th European Conference on Technology Enhanced Learning (EC-TEL 2014) 2014,

   Abs

   Within the health sector, the effectiveness is a key factor for the deployment of Serious Games for training purposes. Engagement is central factor relating games to learning. Therefore, identifying player’s level of engagement is an important aspect to consider when assessing Serious Games effectiveness. This paper describes an approach to identify player’s engaged-behaviours based on users interaction traces. A trace is a history of users’ actions collected in real-time during their inter-action with a computer system. The process of identifying the level of engagement consists of transforming low-level behaviours (e.g. clicks) in contextualized high-level behaviours. The proposed approach is exemplified by applying it to the identification of engaged-behaviours in a serious game for training clinical procedures on sepsis treatment protocol.

4. IEEE

   SeGTE: A serious game to train and evaluate basic life support

   Ribeiro, Claudia, Tiago, Joana, Monteiro, Micaela, and Pereira, João

   In 2014 International Conference on Computer Graphics Theory and Applications (GRAPP) 2014,

   Abs HTML PDF

   Basic life support (BLS) is the level of medical care which is used for victims of life-threatening illnesses or injuries until they can be given full medical care at a hospital. It can be provided by trained medical personnel, including emergency medical technicians, paramedics, and by laypersons who have received BLS training. BLS is generally used in the pre-hospital setting, and can be provided without medical equipment. The ability to respond to an emergency situation can be the difference between life and death. Acknowledging this fact has made decision-makers, governments and Non Government Organizations (NGO) to make a priority to spread this knowledge and skills to the general population. Currently, BLS is taught in a standard course provided by the Red Course or certified entities, where the pedagogical content given to the students is a mix of theoretical and practical training where life-size mannequin are used. In this paper we argue that serious games could help spread this knowledge through the general population and it could also be used to refresh the knowledge of people that have been certified in BLS in the past. In order to test this hypothesis we have developed the SeGTE game and performed an evaluation of its effectiveness on conveying such pedagogical content.

5. IGI Global

   Critical Transport: A Serious Game to Teach the Recommendations for the Transport of Critically Ill Patients

   Ribeiro, Claudia, Antunes, Tiago, Pereira, João, and Monteiro, Micaela

   International Journal of Game-Based Learning (IJGBL) 2014,

   Abs HTML PDF

   At present, medical knowledge is experiencing an exponential growth. This results in serious difficulties to healthcare professionals in keeping up to date. At the same time, medical education is mostly taught using traditional learning methodologies, not always the most efficient. Recently however, there has been a significant increase in the use of computer games for both teaching and training as several published studies are showing that serious games can be more efficient when compared to traditional learning methodologies. Although the current number of serious games used in medical education is still very limited, the authors agree that it’s application could lead to the improvement of medical knowledge and skills. This paper describes the serious game Critical Transport which is based on the Portuguese Society of Intensive Care’s recommendations for the transport of critically ill patients, as well as the results of a pre/post-test study focused in determining the Critical Transport serious game efficiency as a training tool for training medical students.

6. Elsevier

   Gamifying requirement elicitation: Practical implications and outcomes in improving stakeholders collaboration

   Ribeiro, Claudia, Farinha, Carla, Pereira, João, and Silva, Miguel Mira

   Entertainment Computing 2014,

   Abs HTML PDF

   The requirements engineering process is a key phase of the Information System development since it determines its functionalities and its operation. Before requirements can be analyzed, modeled, or specified they must be gathered through an elicitation process. Requirements elicitation is non-trivial because you can never be sure you get all requirements from the user or stakeholder by just asking them what the system should do. Requirements elicitation practices include interviews, questionnaires, user observation, workshops, brainstorming, use cases, role playing and prototyping. However, these common procedures are still prone to be ambiguous or incorrect which can lead the Information Systems to failure. It is consensual that one of the major problem of this activity relates to the communication and collaboration between different and distant stakeholders. Thus, recent studies have been proposing web collaborative tools to gather these stakeholders in order to elicit requirements. The paper aims to evaluate the effectiveness and acceptance of such a collaborative tool which was developed by using a gamification approach and the Six Thinking Hats method. The document also makes a discussion of the implication and outcomes of improving stakeholders collaboration.

2015

1. IGI Global

   Critical Transport: A Serious Game to Teach the Recommendations for the Transport of Critically Ill Patients

   Ribeiro, Claudia, Antunes, Tiago, Pereira, João, and Monteiro, Micaela

   2015,

   Abs HTML

   At present, medical knowledge is experiencing an exponential growth. This results in serious difficulties to healthcare professionals in keeping up to date. At the same time, medical education is mostly taught using traditional learning methodologies, not always the most efficient. Recently however, there has been a significant increase in the use of computer games for both teaching and training as several published studies are showing that serious games can be more efficient when compared to traditional learning methodologies. Although the current number of serious games used in medical education is still very limited, the authors agree that it’s application could lead to the improvement of medical knowledge and skills. This paper describes the serious game Critical Transport which is based on the Portuguese Society of Intensive Care’s recommendations for the transport of critically ill patients, as well as the results of a pre/post-test study focused in determining the Critical Transport serious game efficiency as a training tool for training medical students.

2. GRAPP

   Virtual Agents and Multi-modality of Interaction in Multimedia Applications for Cultural Heritage - A Case Study

   Neto, João, Ribeiro, Claudia, Pereira, João, and João Neto, Maria

   2015,

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   Cultural Heritage encompasses a set of traditions and commodities inherited from our ancestors, and it is vital to convey and preserve them for the next generation. Cultural Multimedia applications and Serious Games form an important pedagogical and didactic medium, mainly for a young demography, which can learn while playing. In this paper is presented an innovative platform, named EI2VA (Engine for Immersive Interaction with Virtual Agents), in which a virtual character, endowed with facial, corporal and behavioural animation can be integrated in multimedia applications. These multimedia applications, derived from the Fala Comigo project, which set the example for a possible use of this technology, preserving the historical and cultural contents indispensable for the users, based on a multi-modality of evident interaction. The resulting multimedia applications were used in a case study conduct with three different user groups (experts and nonexperts) in different settings including classroom, museum and scientific conference.

2016

1. ACM

   3D Annotation in Contemporary Dance: Enhancing the Creation-Tool Video Annotator

   Ribeiro, Claudia, Kuffner, Rafael, Fernandes, Carla, and Pereira, João

   In Proceedings of the 3rd International Symposium on Movement and Computing 2016,

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   Annotated videos have been used in the context of dance performance not only as a way to record and share compositions and knowledge between different choreographers, but also as a powerful learning tool. Restraining the viewpoint of the user to the recorded point of view can be an obstacle in several scenarios. Alternatives that introduce the concept of a three-dimensional space have been developed, but coming short either on the freedom of concepts that the user is able to introduce, or on resorting to a non-natural representation. This article describes a follow-up work on the previously developed Creation-Tool [2] extending the existing functionality to tackle this problem. The developed system places the 2D annotations onto a three-dimensional point cloud, captured by depth sensors coupled with cameras around the performance, thus enabling the user to freely visualize the annotated performance three-dimensionally at an arbitrary point of view.

2. IEEE

   Sepsis Fast Track: A simulation game for Clinical education based on the Sepsis Fast Track protocol

   Ribeiro, Claudia, Monteiro, Micaela, Hauge, Jannicke Baalsrud, Pereira, Joao, and Antunes, Tiago

   In 2016 IEEE International Conference on Serious Games and Applications for Health (SeGAH) 2016,

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   Sepsis is a serious medical condition responsible for high levels of in-hospital mortality. It requires fast diagnosis and treatment, since the survival rate decreases 7.6% for every hour without treatment. In order to facilitate this process of diagnosis and medical therapy, the Portuguese Directorate-General of Health issued a document regulating the implementation of a Sepsis Fast Track protocol based on the Surviving Sepsis Campaign guidelines. Training of emergency department healthcare professionals is essential, and should be attended regularly in order to refresh knowledge and to be made aware of updates to any changes of the protocol. Currently, this training is conducted through traditional learning methods often considered as outdated for the younger generation, the so-called "digital natives". The usage of serious games is a trend that has been considered when discussing new tools for teaching and training in various fields, including healthcare. Several research works on the impact of applying such technologies in healthcare, stating that serious games could provide new approaches and opportunities have been published. This paper presents the Sepsis Fast Track serious game. It is a serious game developed to teach and train nurses and physicians working in hospital Emergency Departments on the Sepsis Fast Track protocol. An evaluation study carried out with the healthcare professionals is also presented. The main goal of which was to evaluate the impact of serious games on professional working practices.

2017

1. Visualization Techniques as Methodological Tools for Dance Research

   Ribeiro, Claudia, and Evola, Vito

   In Proceedings of the 5th International Conference on Computation, Communication, Aesthetics & X 2017,

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   Dance Research is a term that refers to the methods and methodological approaches used in dance studies, a relatively new academic discipline. In this paper we describe how visualization techniques can be used to help the dance researcher visualize in a more intuitive manner the concepts underlying a choreographer’s work. We describe tools developed for and used by researchers interested in improvisation and dance research, and we provide practical examples of how they were used to analyze choreographer João Fiadeiro’s Real Time Composition (CTR) Method.

2. ACM

   Capturing and documenting creative processes in contemporary dance

   Ribeiro, Claudia, Anjos, Rafael Kuffner, and Fernandes, Carla

   In Proceedings of the 4th International Conference on Movement Computing 2017,

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   The performing arts, and dance in particular, have been considered as intangible cultural heritage by UNESCO since 2003. This acknowledgement reflects the importance of preserving the knowledge generated within this art form for future generations. Nevertheless, what and how this sensible material should be preserved is still lacking clear methodological approaches. When considering creative processes, this seems an even more daunting task, as it goes beyond simply documenting the final product of a creation. Recent advancements in technology has allowed to consider other approaches of capturing data apart from video or photography, which are mostly static and have a single viewpoint. In this paper we describe how 3D data capture and point cloud visualization techniques have been used to capture and document João Fiadeiro’s choreographic and compositional processes. Together with Fiadeiro we have identified a sub-set of core concepts of his method which have then been used to conduct two improvisation sessions involving Fiadeiro’s dancers and himself. Those concepts have been used as the basis for the development of new visualization techniques that better illustrate, in an interactive system, the complexity of Fiadeiro’s creative process.

2018

1. Springer

   Stroke-based splatting: an efficient multi-resolution point cloud visualization technique

   Anjos, Rafael Kuffner, Ribeiro, Claudia Sofia, Lopes, Daniel Simões, and Pereira, João Madeiras

   The Visual Computer 2018,

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   Current state-of-the-art point cloud visualization techniques have shortcomings when dealing with sparse and less accurate data or close-up interactions. In this paper, we present a visualization technique called stroke-based splatting, which applies concepts of stroke-based rendering to surface-aligned splatting, allowing for better shape perception at lower resolutions and close-ups. We create a painterly depiction of the data with an impressionistic aesthetic, which is a metaphor the user is culturally trained to recognize, thus attributing higher quality to the visualization. This is achieved by shaping each object-aligned splat as a brush stroke, and orienting it according to globally coherent tangent vectors from the Householder formula, creating a painterly depiction of the scanned cloud. Each splat is sized according to a color-based clustering analysis of the data, ensuring the consistency of brush strokes within neighborhood areas. By controlling brush shape generation parameters and blending factors between neighboring splats, the user is able to simulate different painting styles in real time. We have tested our method with data sets captured by commodity laser scanners as well as publicly available high-resolution point clouds, both having highly interactive frame rates in all cases. In addition, a user study was conducted comparing our approach to state-of-the-art point cloud visualization techniques. Users considered stroke-based splatting a valuable technique as it provides a higher or similar visual quality to current approaches.

2. Springer

   Virtual Reality Annotator: A Tool to Annotate Dancers in a Virtual Environment

   Ribeiro, Claudia, Kuffner, Rafael, and Fernandes, Carla

   In Digital Cultural Heritage: Final Conference of the Marie Skłodowska-Curie Initial Training Network for Digital Cultural Heritage, ITN-DCH 2017, Olimje, Slovenia, May 23–25, 2017, Revised Selected Papers 2018,

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   In this paper we describe the Virtual Reality Annotator, a visualization tool that allows users to dynamically annotate dancers in a virtual reality environment. The current annotation types supported are sketches, speech-to-text, and highlighting. Each type of annotation can be applied to a bone or a set of bones of the skeleton data or a set of points of the point-cloud data. Using a wireless mouse, users can interact with the 3D objects of the virtual reality space, specifically a 3D menu that allows to choose the type of annotation and desired color as well as the skeleton and point cloud data. Examples of usage of this system using data from expert dancers are presented and discussed as well as suggestions for future work.

3. ACM

   Three-Dimensional Visualization of Movement Qualities in Contemporary Dance

   Anjos, Rafael Kuffner dos, Ribeiro, Claudia, and Fernandes, Carla

   In Proceedings of the 5th International Conference on Movement and Computing 2018,

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   Analyzing and documenting contemporary dance movement data has proven to be a very difficult task due to the vast existence of styles and aesthetics which are characteristic of each individual choreographer. Indeed, identifying movement qualities with the intention of co-relating them to specific meanings and choreographic intentions is practically impossible without taking an artist-driven approach. Moreover, equipping dancers with wearable technology in order to accurately track each of their movements is only applicable in controlled laboratory scenarios, therefore not being a viable approach to analyze large scale real-world rehearsals or performances. This paper describes a visualization system that exposes movement qualities for dance through rendering effects. Combining optical flow analysis with depth video information, we were able to estimate the three-dimensional flow for each point in the cloud. This information was used to color point cloud videos with this information, showing potential to be used for the creation of different rendering effects, which are also discussed in this paper. The data used was captured in a non-intrusive manner during the creation process of a dance piece by Portuguese choreographer Rui Lopes Graça, enabling us to examine nuances and details of the rehearsals’ process, which would not be replicable in a laboratory environment.

4. Emerald

   Virtual reality as integration environments for facilities management: Application and users perception

   Carreira, Paulo, Castelo, Tiago, Gomes, Cristina Caramelo, Ferreira, Alfredo, Ribeiro, Claudia, and Costa, Antonio Aguiar

   Engineering, Construction and Architectural Management 2018,

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   The purpose of this paper is to explore the use of virtual reality environments (VRE) for maintenance activities by augmenting a virtual facility representation and integrating relevant information regarding the status of systems and the space itself, while providing simple ways to control them.

2022

1. VISIGRAPP

   Emotional and Engaging Movie Annotation with Gamification

   Nunes, Lino, Ribeiro, Claudia, and Chambel, Teresa

   In Proceedings of the 17th International Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications - Volume 2: HUCAPP 2022,

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   Entertainment has always been present in human activities, satisfying needs and playing a role in the lives of individuals and communities. In particular, movies have a strong emotional impact on us, with their rich multimedia content and their stories; while games tend to defy and engage us facing challenges and hopefully achieving rewarding experiences and results. In this paper, we present a web application being designed and developed to access movies based on emotional impact, with the focus on the emotional annotation of movies, using different emotional representations, and gamification elements to further engage users in this task, beyond their intrinsic motivation. These annotations can help enriching emotional classification of movies and their impact on users, with machine learning approaches, later helping to find movies based on this impact; and they can also be collected as personal notes like on a journal where users collect the movies they treasure the most, and that they can review and even compare along their journey. We also present a preliminary user evaluation, allowing to assess and learn about its perceived utility, usability and user experience, and to identify most promising features and directions for further improvements and developments.

2. Routledge

   Dance Data, Cognition and Multimodal Communication

   Fernandes, Carla, Evola, Vito, and Ribeiro, Claudia

   2022,

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   Dance Data, Cognition, and Multimodal Communication is the result of a collaborative and transdisciplinary effort towards a first definition of "dance data", with its complexities and contradictions, in a time where cognitive science is growing in parallel to the need of a renewed awareness of the body’s agency in our manyfold interactions with the world. It is a reflection on the observation of bodily movements in artistic settings, and one that views human social interactions, multimodal communication, and cognitive processes through a different lens—that of the close collaboration between performing artists, designers, and scholars. This collection focuses simultaneously on methods and technologies for creating, documenting, or representing dance data. The editors highlight works focusing on the dancers’ embodied minds, including research using neural, cognitive, behavioural, and linguistic data in the context of dance composition processes. Each chapter deals with dance data from an interdisciplinary perspective, presenting theoretical and methodological discussions emerging from empirical studies, as well as more experimental ones. The book, which includes digital Support Material on the volume’s Routledge website, will be of great interest to students and scholars in contemporary dance, neuro-cognitive science, intangible cultural heritage, performing arts, cognitive linguistics, embodiment, design, new media, and creativity studies.

3. IEEE

   Annotate Smarter, Not Harder: Using Active Learning to Reduce Emotional Annotation Effort

   Alarcão, M. Soraia, Mendonça, Vânia, Ribeiro, Cláudia, Maruta, Carolina., and Fonseca, Manuel João

   Transactions on Affective Computing 2022, Manuscript submitted for publication

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   The success of supervised models for emotion recognition on images heavily depends on the availability of images properly annotated. Although millions of images are presently available, only a few are annotated with reliable emotional information. Current solutions either use large amounts of weakly-labeled web images, which often contain noise that is unrelated to the emotions of the image, or transfer learning, which usually results in performance losses. Thus, it would be desirable to know which images would be useful to be annotated to avoid an extensive annotation effort. In this paper, we propose a novel approach to choose which images are more relevant to be annotated by humans using active and online learning. Our approach dynamically combines multiple active learning strategies and learns the best ones (without prior knowledge of which ones would be the best). Experiments using nine benchmark datasets revealed that: (i) both the best individual strategies and our combination achieved a performance very similar to the baseline, and in most cases even surpassed it (using on average only 33% of the number of images used by the baseline); (ii) our combination of strategies successfully and quickly converges to the performance of the best individual strategy without any annotation effort and experimentation overhead.

4. Elsevier

   Unfolding Handcrafted Features Contribution in CNNs for Valence and Arousal Estimation in Images

   Alarcão, M. Soraia, Ribeiro, Cláudia, Garcia, Nuno, Maruta, Carolina., and Fonseca, Manuel João

   Journal of Visual Communication and Image Representation 2022, Manuscript submitted for publication

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   Emotions play an important role in our daily lives, affecting several aspects of human cognition and behaviour. Thus, being able to automatically assess the emotional impact an image will have on viewers can be useful in numerous applications. Affective Image Content Analysis (AICA) has gained increasing attention over the past few decades. While the first approaches relied on handcrafted visual features to attribute an emotional classification to an image, more recent works explore features learned using pre-trained Convolutional Neural Networks (CNN) to leverage the performance achieved in object classification in the context of AICA. Although the use of either handcrafted and deep features has achieved promising results, it has not yet been possible to attain human-level performance. In this paper, we shed some light on the impact of combining handcrafted with learned features for the estimation of valence and arousal values. First, we identified 30 discriminant handcrafted visual and semantic features for the estimation of valence and arousal using statistical analysis. Then, we analysed the impact of using the discriminant handcrafted features on three well-known CNN architectures (VGG16, InceptionV3, ResNet50) using transfer learning, and a Multilayer Perceptron (MLP). Experiments conducted on nine benchmark datasets revealed that the use of color and semantic information with the ResNet50 has yielded promising results for valence. For arousal, deep features from the ResNet50 achieved better results than its combination with the handcrafted features. The MLP achieved superior results than the ResNet50 for both valence and arousal using only one semantic feature.