Publications

[Anonymous].  2006.  Interacção 2006 - Actas da 2a. Conferência Nacional em Interacção Pessoa-Máquina. Interação 2006. :240. Abstract

A concepção e desenvolvimento de sistemas interactivos envolve aspectos que vão desde a psicologia à engenharia de software. Recentemente verificou-se uma rápida evolução nesta área multidisciplinar, tanto a nível tecnológico, como do contexto de utilização da tecnologia. Assim, às tradicionais preocupações com a eficácia, eficiência e satisfação, juntam-se agora questões como entretenimento, design, estética, cooperação, ubiquidade e adaptabilidade. Paralelamente, o leque de utilizadores alvo dos sistemas é cada vez mais alargado, existindo a preocupação de desenvolver interfaces para pessoas e contextos de utilização com diferentes tipos de necessidades e requisitos ao nível físico ou cognitivo. Torna-se assim necessário perceber o impacto destas novas realidades no processo de interacção e no desenvolvimento de sistemas interactivos.
Depois do sucesso da primeira edição, organizada em Julho de 2004 na Faculdade de Ciência da Universidade de Lisboa, organizou-se agora a Interacção 2006 – 2a. Conferência Nacional em Interacção Pessoa-Máquina – numa iniciativa conjunta do Grupo Português de Computação Gráfica e do Departamento de Informática/Centro de Ciências da Computação da Universidade do Minho. Tal como na sua primeira edição, a Interacção 2006 visou promover um ponto de encontro da comunidade interessada na Interacção Pessoa-Máquina em Portugal. Reunindo investigadores, docentes e profissionais, permitiu a divulgação de trabalhos e a troca de experiências entre as comunidades académica e industrial.
Adoptando uma postura marcadamente multidisciplinar, a conferência desafiou os autores a abordar desde os fundamentos teóricos às práticas e aplicações emergentes, visando explorar sinergias nas seguintes dimensões:
• Aspectos Teóricos em Interacção Pessoa-Máquina
• Concepção, Desenvolvimento e Avaliação de Sistemas Interactivos • Tecnologias de Suporte à Interacção
• Aplicações Interactivas
Em resposta a este desafio, foram recebidos trabalhos de Portugal, Espanha e Brasil.
Como resultado do processo de revisão dos trabalhos propostos, foram organizadas sete sessões técnicas em que foram
apresentados 13 artigos longos e 16 artigos curtos, bem como uma sessão de posters e demonstrações em que foram apresentados 9 trabalhos. Para complementar o programa técnico foram ainda organizadas duas sessões proferidas por convidados internacionais de renome e uma sessão dedicada à indústria, em que se convidaram empresas e uma associação a apresentar a sua perspectiva sobre o tema da Usabilidade.
A conferência decorreu entre os dias 16 e 18 de Outubro de 2006, nas instalações da Universidade do Minho, Campus de Gualtar, em Braga. Procurou-se que ela fosse um retrato do trabalho que vem sendo desenvolvido nesta área em Portugal. Assim, as sessões técnicas desenvolveram-se em torno de sete temas principais, seleccionados a partir da análise dos trabalhos aceites: Acessibilidade, Psicologia Cognitiva e Colaboração, Concepção e Desenvolvimento, Interfaces Multi-modais e Adaptativas, Realidade Virtual e Aumentada, Vizualização e Pesquisa de Informação, e Avaliação. Sem se tratar de uma classificação estanque, pensamos ser esta uma organização natural e abrangente dos trabalhos apresentados.
Terminamos agradecendo aos membros do Comité Organizador e da Comissão de Programa todo o seu trabalho, aos oradores convidados, Michael D. Harrison e Larry L. Constantine, bem como às instituições que aceitaram o desafio de participar na sessão dedicada à indústria (Associação Portuguesa de Profissionais de Usabilidade, MobiComp, Wintouch e Edigma.com) e a todos os autores. Agradecemos finalmente a todos os patrocinadores por nos ajudarem a tornar este evento possível. Esperamos que esta tenha sido mais uma contribuição para fomentar a partilha e colaboração da comunidade Interacção Pessoa-Máquina em Portugal.

Harrison M, Masci P, Campos JC.  2018.  Verification templates for the analysis of user interface software design. IEEE Transactions on Software Engineering (to appear). Abstractnewtemplates-r1v7b.pdfhttps://doi.org/10.1109/TSE.2018.2804939

The paper describes templates for model-based analysis of usability and safety aspects of user interface software design. The templates crystallize general usability principles commonly addressed in user-centred safety requirements, such as the ability to undo user actions, the visibility of operational modes, and the predictability of user interface behavior. These requirements have standard forms across different application domains, and can be instantiated as properties of specific devices. The modeling and analysis process is carried out using the Prototype Verification System (PVS), and is further facilitated by structuring the specification of the device using a format that is designed to be generic across interactive systems. A concrete case study based on a commercial infusion pump is used to illustrate the approach. A detailed presentation of the automated verification process using PVS shows how failed proof attempts provide precise information about problematic user interface software features.

Harrison MD, Masci P, Campos JC, Curzon P.  2017.  Verification of User Interface Software: the Example of Use-Related Safety Requirements and Programmable Medical Devices. IEEE Transactions on Human-Machine Systems. 47:834-846. Abstractmedthmsv9-author_version.pdf

One part of demonstrating that a device is acceptably safe, often required by regulatory standards, is to show that it satisfies a set of requirements known to mitigate hazards. This paper is concerned with how to demonstrate that a user interface software design is compliant with use-related safety requirements. A methodology is presented based on the use of formal methods technologies to provide guidance to developers about addressing three key verification challenges: (i) how to validate a model, and show that it is a faithful representation of the device;
(ii) how to formalize requirements given in natural language, and demonstrate the benefits of the formalization process; (iii) how to prove requirements of a model using readily available formal verification tools. A model of a commercial device is used throughout the paper to demonstrate the methodology. A representative set of requirements are considered. They are based on US Food and Drug Administration (FDA) draft documentation
for programmable medical devices, and on best practice in user interface design illustrated in relevant international standards. The methodology aims to demonstrate how to achieve the FDA’s agenda of using formal methods to support the approval process for medical devices.

Campos JC, Fayollas C, Gonçalves M, Martinie C, Navarre D, Palanque P, Pinto M.  2017.  A ``More Intelligent'' Test Case Generation Approach through Task Models Manipulation. Proceedings of the ACM on Human-Computer Interaction – EICS. 1:Article9. Abstractpacmhci-eics17-accepted.pdf

Ensuring that an interactive application allows users to perform their activities and reach their goals is critical to the overall usability of the interactive application. Indeed, the effectiveness factor of usability directly refers to this capability. Assessing effectiveness is a real challenge for usability testing as usability tests only cover a very limited number of tasks and activities. This paper proposes an approach towards automated testing of effectiveness of interactive applications. To this end we resort to two main elements: an exhaustive description of users’ activities and goals using task models, and the generation of scenarios (from the task models) to be tested over the application. However, the number of scenarios can be very high (beyond the computing capabilities of machines) and we might end up testing multiple similar scenarios. In order to overcome these problems, we propose strategies based on task models manipulations (e.g., manipulating task nodes, operator nodes, information...) resulting in a more intelligent test case generation approach. For each strategy, we investigate its relevance
(both in terms of test case generation and in terms of validity compared to the original task models) and we illustrate it with a small example. Finally, the proposed strategies are applied on a real-size case study demonstrating their relevance and validity to test interactive applications.

Campos JC, Abade T, Silva JL, Harrison MD.  2017.  Don't Go In There! Using the APEX framework in the design of Ambient Assisted Living Systems. Journal of Ambient Intelligence and Humanized Computing. 8:551-566. Abstract17-jaihc-author-2.pdf

An approach to design Ambient Assisted Living systems is presented, which is based on APEX, a framework for prototyping ubiquitous environments. The approach is illustrated through the design of a smart environment within a care home for older people. Prototypes allow participants in the design process to experience the proposed design and enable developers to explore design alternatives rapidly. APEX provides the means to explore alternative environment designs virtually. The prototypes developed with APEX offered a mediating representation, allowing users to be involved in the design process. A group of residents in a city-based care home were involved in the design. The paper describes the design process as well as lessons learned for the future design of AAL systems.

Campos JC, Sousa M, Alves M, Harrison M.  2016.  Formal Verification of a Space System's User Interface with the IVY workbench. IEEE Transactions on Human-Machine Systems. 46(2):303-316. Abstractthms-paper-author_version.pdf

This paper describes the application of the IVY workbench to the formal analysis of a user interface for a safety-critical aerospace system. The operation manual of the system was used as a requirement document, and this made it possible to build a reference model of the user interface, focusing on navigation between displays, the information provided by each display, and how they are interrelated. Usability-related property specification patterns were then used to derive relevant properties for verification. This paper discusses both the modeling strategy and the analytical results found using the IVY workbench. The purpose of the reference model is to provide a standard against which future versions of the interface may be assessed.

Couto R, Ribeiro AN, Campos JC.  2015.  The Modelery: A Model-Based Software Development Repository. International Journal of Web Information Systems. Abstractijwisv2.pdf

Purpose
– This paper aims to present the Modelery, a platform for collaborative repository to support model-based software development. The Modelery is a Web platform, composed both by a Web page and Web services for interoperability.

Design/methodology/approach
– By performing a study in the existing platforms, it was possible to achieve a set of issues to tackle. The issues enabled the possibility to define a set of requirements that allowed the authors to design a new platform, and to perform a model-driven software development process, which started from the requirements until reaching the final software solution.

Findings
– With this work, it was possible to perform a survey on the currently available artifacts repositories, categorize them and identify their shortcomings. This was essential to define the set of requirements for a new platform to overcome the identified issues. This process leads to a platform able to improve the currently available solutions, and validated in the scientific community. In this paper, the authors also explore the applications of the repository. First, they use the Modelery to replace an older model’s repository. Second, they have enabled the communication between other tools and the Modelery via Web services.

Originality/value
– This work presents a new Web repository for software artifacts aimed at supporting researchers and software developers. The presented platform is an improvement over other platforms on the integration of artifacts repository, social functionalities and scientific publications integration. The authors conclude this paper by comparing the achieved platform in terms of functionalities, against the other analyzed platforms.

Harrison M, Campos JC, Masci P.  2015.  Reusing models and properties in the analysis of similar interactive devices. Innovations in Systems and Software Engineering. 11:95-111. Abstractharros.pdf

The paper is concerned with the comparative analysis of interactive devices. It compares two devices by checking systematically a set of template properties that are designed to explore important interface characteristics. The two devices are designed to support similar tasks in a clinical setting. The devices differ as a result of judgements based on a range of considerations including software. Variations between designs are often relatively subtle and do not always become evident through even relatively thorough user testing. Notwithstanding their subtlety, these differences may be important to the safety or usability of the device. The illustrated approach uses formal techniques to provide the analysis. This means that similar analysis can be applied systematically.

Campos JC, Doherty G, Harrison M.  2014.  Analysing interactive devices based on information resource constraints. International Journal of Human-Computer Studies. 72(3):284-297. Abstract1-s2.0-s1071581913001407-main.pdf

Analysis of the usability of an interactive system requires both an understanding of how the system is to be used and a means of assessing the system against that understanding. Such analytic assessments are particularly important in safety-critical systems as latent vulnerabilities may exist which have negative consequences only in certain circumstances. Many existing approaches to assessment use tasks or scenarios to provide explicit representation of their understanding of use. These normative user behaviours have the advantage that they clarify assumptions about how the system will be used but have the disadvantage that they may exclude many plausible deviations from these norms. Assessments of how a design fails to support these user behaviours can be a matter of judgement based on individual experience rather than evidence. We present a systematic formal method for analysing interactive systems that is based on constraints rather than prescribed behaviour. These constraints capture precise assumptions about what information resources are used to perform action. These resources may either reside in the system itself or be external to the system. The approach is applied to two different medical device designs, comparing two infusion pumps currently in common use in hospitals. Comparison of the two devices is based on these resource assumptions to assess consistency of interaction within the design of each device.

Gomes T, Abade T, Campos JC, Harrison M, Silva JL.  2014.  A Virtual Environment based Serious Game to Support Health Education. EAI Endorsed Transactions on Ambient Systems. 14(3):e5. Abstractamsys.1.3.e5.pdf

APEX was developed as a framework for ubiquitous computing (ubicomp) prototyping through virtual environments. In this paper the framework is used as a platform for developing a serious game designed to instruct and to inform. The paper describes the Asthma game, a game aimed at raising awareness among children of asthma triggers in the home. It is designed to stimulate a healthier life-style for those with asthma and respiratory problems. The game was developed as the gamification of a checklist for the home environment of asthma patients.

Silva JL, Campos JC, Harrison M.  2014.  Prototyping and Analysing Ubiquitous Computing Environments using Multiple Layers. International Journal of Human-Computer Studies. 72(5):488-506. Abstractijhcs-silvach14-preprint.pdf

If ubiquitous computing (ubicomp) is to enhance physical environments then early and accurate assessment of alternative solutions will be necessary to avoid costly deployment of systems that fail to meet requirements. This paper presents APEX, a prototyping framework that combines a 3D Application Server with a behaviour modeling tool. The contribution of this framework is that it allows exhaustive analysis of the behaviour models that drive the prototype while at the same time enabling immersive exploration of a virtual environment simulating the proposed system. The development of prototypes is supported through three layers: a simulation layer (using OpenSimulator); a modelling layer (using CPN Tools) and a physical layer (using external devices and real users). APEX allows movement between these layers to analyse different features, from user experience to user behaviour. The multi layer approach makes it possible to express user behaviour in the modelling layer, provides a way to reduce the number of real users needed by adding simulated avatars, and supports user testing of hybrids of virtual and real components as well as exhaustive analysis. This paper demonstrates the approach by means of an example, placing particular emphasis on the simulation of virtual environments, low cost prototyping and the formal analysis capabilities.

Harrison M, Campos JC, Masci P.  2013.  Reusing models and properties in the analysis of similar interactive devices. Innovations in Systems and Software Engineering. 2(11):95-111. Abstractharrisoncm15-authorsversion.pdf

The paper is concerned with the comparative analysis of interactive devices. It compares two devices by checking a battery of template properties that are designed to explore important interface characteristics. The two devices are designed to support similar tasks in a clinical setting but differ in a number of respects as a result of judgements based on a range of considerations including software. Variations between designs are often relatively subtle and do not always become evident through even relatively thorough user testing. Notwithstanding their subtlety these differences may be important to the safety or usability of the device. The illustrated approach uses formal techniques to provide the analysis. This means that similar analysis can be applied systematically.

Silva CC, Mendonça C, Mouta S, Silva R, Campos JC, Santos J.  2013.  Depth cues and perceived audiovisual synchrony of biological motion. PLOS One. 8(1) Abstractjournal.pone_.0080096.pdf

Background

Due to their different propagation times, visual and auditory signals from external events arrive at the human sensory receptors with a disparate delay. This delay consistently varies with distance, but, despite such variability, most events are perceived as synchronic. There is, however, contradictory data and claims regarding the existence of compensatory mechanisms for distance in simultaneity judgments.

Principal Findings

In this paper we have used familiar audiovisual events – a visual walker and footstep sounds – and manipulated the number of depth cues. In a simultaneity judgment task we presented a large range of stimulus onset asynchronies corresponding to distances of up to 35 meters. We found an effect of distance over the simultaneity estimates, with greater distances requiring larger stimulus onset asynchronies, and vision always leading. This effect was stronger when both visual and auditory cues were present but was interestingly not found when depth cues were impoverished.

Significance

These findings reveal that there should be an internal mechanism to compensate for audiovisual delays, which critically depends on the depth information available.

Campos JC, Machado J.  2013.  A Specification Patterns System for Discrete Event Systems' Analysis. International Journal of Advanced Robotic Systems. 10:315. Abstract45610.pdf

As formal verification tools gain popularity, the problem arises of making them more accessible to engineers. A correct understanding of the logics used to express properties of a system's behavior is needed in order to guarantee that properties correctly encode the intent of the verification process. Writing appropriate properties, in a logic suitable for verification, is a skillful process. Errors in this step of the process can create serious problems since a false sense of safety is gained with the analysis. However, when compared to the effort put into developing and applying modeling languages, little attention has been devoted to the process of writing properties that accurately capture verification requirements. In this paper we illustrate how a collection of property patterns can help in simplifying the process of generating logical formulae from informally expressed requirements.

Freire L, Arezes P, Campos JC.  2012.  A literature review about usability evaluation methods for e-learning platforms. Work: A Journal of Prevention, Assessment and Rehabilitation. 41:1038-1044. Abstractfulltext.pdf

The usability analysis of information systems has been the target of several research studies over the past thirty years. These studies have highlighted a great diversity of points of view, including researchers from different scientific areas such as Ergonomics, Computer Science, Design and Education. Within the domain of information ergonomics, the study of tools and methods used for usability evaluation dedicated to E-learning presents evidence that there is a continuous and dynamic evolution of E-learning systems, in many different contexts -academics and corporative. These systems, also known as LMS (Learning Management Systems), can be classified according to their educational goals and their technological features. However, in these systems the usability issues are related with the relationship/interactions between user and system in the user’s context. This review is a synthesis of research project about Information Ergonomics and embraces three dimensions, namely the methods, models and frameworks that have been applied to evaluate LMS. The study also includes the main usability criteria and heuristics used. The obtained results show a notorious change in the paradigms of usability, with which it will be possible to discuss about the studies carried out by different researchers that were focused on usability ergonomic principles aimed at E-learning.