Francisco Rebelo

Behavioral compliance for dynamic versus static signs in an immersive virtual environment.

This study used an immersive virtual environment (IVE) to examine how dynamic features in signage affect behavioral compliance during a work-related task and an emergency egress. Ninety participants performed a work-related task followed by an emergency egress. Compliance with uncued and cued safety signs was assessed prior to an explosion/fire involving egress with exit signs. Although dynamic presentation produced the highest compliance, the difference between dynamic and static presentation was only statistically significant for uncued signs. Uncued signs, both static and dynamic, were effective in changing behavior compared to no/minimal signs. Findings are explained based on sign salience and on task differences. If signs must capture attention while individuals are attending to other tasks, salient (e.g., dynamic) signs are useful in benefiting compliance. This study demonstrates the potential for IVEs to serve as a useful tool in behavioral compliance research.

Using Virtual Reality to Assess User Experience

Objective: The aim of this article is to discuss how user experience (UX) evaluation can benefit from the use of virtual reality (VR). Background: UX is usually evaluated in laboratory settings. However, considering that UX occurs as a consequence of the interaction between the product, the user, and the context of use, the assessment of UX can benefit from a more ecological test setting. VR provides the means to develop realistic-looking virtual environments with the advantage of allowing greater control of the experimental conditions while granting good ecological validity. Method: The methods used to evaluate UX, as well as their main limitations, are identified. The current VR equipment and its potential applications (as well as its limitations and drawbacks) to overcome some of the limitations in the assessment of UX are highlighted. Results: The relevance of VR for UX studies is discussed, and a VR-based framework for evaluating UX is presented. Conclusion: UX research may benefit from a VR-based methodology in the scopes of user research (e.g., assessment of users’ expectations derived from their lifestyles) and human–product interaction (e.g., assessment of users’ emotions since the first moment of contact with the product and then during the interaction). Application: This article provides knowledge to researchers and professionals engaged in the design of technological interfaces about the usefulness of VR in the evaluation of UX.

Ergonomics in design: solutions and proposals for a better interface with the user

We all use products on a daily basis. This interaction, no matter how simple or complex, must meet users’ expectations and needs in a safe, efficient and pleasurable way. Although this basic principle is basic, interaction between humans and the product/machine does not always occur. According to Karwowski et al. (2011a, b), the application of ergonomic principles and knowledge to the design process helps meet these users’ expectations, thus reducing the risk of malfunction or failures and the potential for accidents and contributes to the product being more readily acceptable. The content of this special edition of TIES – Theoretical Issues in Ergonomics Sciences comprises two issues. In the first, there are seven articles and in the second, eight. The aims of this special edition of TIES are to discuss the relationship between design and ergonomics in the search for solutions and proposals that will enhance both levels of user satisfaction and efficiency in the use of products and systems, and will lead to an increase in comfort and an assurance of safety both under normal conditions and in the presumed misuse of products and systems. In the context applied to products and systems, Ergonomics is understood as a discipline that focuses on the study of the interactions of humans with artefacts from the perspective of science, engineering, design, technology and the management of humancompatibility systems (Karwowski 2005). Ergonomics uses a holistic approach, centred on the user, which considers within its range of action physical, cognitive, social, organisational, environmental and other relevant factors, using appropriate methodologies, to improve design. Thus, Ergonomics is involved in the various decision-making stages when a product is being developed which leads to its having a key role in improving the performance of products. The items of knowledge that come from Ergonomics also consider users’ individual differences and their different characteristics, such as gender, age, physical and mental conditions, etc. The articles in these issues discuss various topics and provide a good reference guide to the breadth of applying Ergonomics when seeking solutions and proposals for a better interface of the product with the user. In the first issue of this special edition, various aspects related to human beings’ communication process are discussed. Teaching is an activity that has accompanied human beings from the earliest prehistoric records. In particular, the application of ergonomics in the field of education is very extensive. Special attention should be given to methods and tools for teaching and learning. New technologies that use motivational aspects, such as games, are being applied successfully and their interfaces analysed (see Rebelo and Filgueiras). A method for teaching physics to indigenous children has been developed by seeking to design an inclusive education program (see Smith-Jackson, Evia, Tabor and Benson). Multidisciplinary aspects and the globalisation of markets have affected the teaching of Ergonomics on Design courses. Di Bucchianico and Camplone introduce a didactic experience that allows young designers to develop their own strategies

A Whole Body Postural Loading Simulation and Assessment Model for Workplace Analysis and Design

Abstract This study reports on the development and validation of a new computer model for simulating human postures at work, and assessing the reaction forces and bending moments in 43 human articulation joints. The proposed model estimates the intradiscal pressure in the vertebral column in response to external loading forces encountered during human interactions with work objects or processes. The model was implemented in a self-contained interactive software package. The simulation results compare favorably with the reported experimental data, and provide reasonable confidence in the quality of the model. Its characteristics and its applications in evaluating physical task performance are also discussed

An expert system to support clothing design process

In the context of expert systems technologies and human computer interaction, the goal of this project is to construct an interactive design support to fashion designers when designing workwear or corporatewear clothes. This system will be fed by a semantic database that describes the relations between function and clothes specific context of use under the users perspective. This application will contain relevant information for clothes designers and producers, alerting them to the users clothes preferences adequate to a certain task, and hopeful, an added value to be included in the beginning of the design process. To gather all this information it will be studied the users real work situation and preferences under Kansei Engineering and Rough Set methodology. The outcomes of this study could help clothing designers to suggest effective user centred design clothes.

Determinants of sleepiness at work among railway control workers

In the last two decades the control of the Portuguese railway network has become much more centralized in three centres, there integrating the functions of route flow management, electrical control and signalling. This study aimed to investigate the influence of work and individual determinants in sleepiness among railway control workers, namely socio-demographic factors, work ability, psychosocial factors, shiftwork characteristics, fatigue perception, and sleep. Sleepiness by shift was associated with quality of sleep, job satisfaction, fatigue perception, quantitative demands, and age. The results indicate a high prevalence of sleepiness during the night shift and show the relevance of the quality of sleep as a predictor in the three models of sleepiness for morning, afternoon and night shifts. This study, done at the major Portuguese railway control centre, alerted managers to the importance of schedule planning as well as sleepiness prevention plans and makes these results a reference for future research.

Support of the upper limbs of office workers during a daily work journey

Generally, the studies assess the upper limbs postures during the work with Visual Display Terminal - VDT through the measurement of the angles formed by the segments or through the relation with the pre-defined anatomical postures (e.g., flexion, extension, abduction). However, few studies were found in the literature which had focused in the measurement of the upper limbs support during a real situation of work with VDT and in the definition of analysis categories for this kind of behavior. The main objective of this study was to measure, in a real situation and using a systematic observation method through video analysis, the main kinds of support for the upper limbs. The analysis was done considering 480 work hours of 30 office workers. Data were collected using a methodology proposed by Rebelo, Filgueiras & Soares [1] and related with the work organization and workspace conditions, the participants had: a) minimum of eight hours daily of work; b) similar activities, characterized as office work; c) same furniture and equipment; and, d) computers with the same hardware, software and peripherals. Results were analyzed 46554 dynamic events, considering only the fourteen Interaction Categories - ICs, for upper limps support. In this way, percentage was computed, considering the total number of occurrence, for the Right arm is: arm support (0.06%); forearm support (31,8%); elbow support (31,92%); hand support (7,41%); multiple supports (12,32%) and without support 16,41%- For the Left arm the results is: forearm support (0,11%); arm support (53,69%); elbow support (8,70%); hand support (7,97%); multiple supports (8,43%) e without support (21,11%). This systemic and ecological approach was obtained through a method which enables experimental Biomechanics and Physiology methods to develop more efficient functional requirements and recommendations for the work with VDTs.

Serious Games and Heuristic Evaluation - The Cross-Comparison of Existing Heuristic Evaluation Methods for Games

Learning by playing has been a desire in the educational domain. The use of serious games may offer the possibility to learn and train at the same time the learner is playing. It makes us consider the serious games as an important research area that can have huge implications in the way the new generations are learning, getting experience, practice knowledge, gain skills, train their habits and reactions. There are many heuristics available in the area of video games, several are presenting repetitive aspects, some are isolated up to the point of reaching contradictory outcomes. The main purpose of this article is to define the nature of serious games and the process of evaluating game. We are taking as the references existing heuristics for games together with their weaknesses and strengths. In order to approach the problem we grouped together and present the most important HEs for games and complied three sets of heuristic evaluation to identify the areas of tangency.

Human-computer interaction in office work: evaluation of interaction patterns using office equipment and software during data entry and navigation

This paper presents a study which objective was to investigate the human interaction with the equipment of an office workstation (mouse, keyboard, monitor, paper sheets, pens and calculator) during the activities of reading, writing, data entry and navigation in a computer system for long periods of time and with ecological validation. A sample of 22800 observations, which corresponds to 760 work-hours of 30 office workers, was classified into sixteen Interactions Categories (IC). The results show that the participants read on the monitor more than on paper and they had a larger use of the mouse instead of the keyboard. Findings of this study allow suggesting what graphical interface designers must seek for new strategies and solutions to reduce the mouse need, exploring other peripherals as keyboard or voice recognition devices; or, at least, diminishing the amplitude of movement with the mouse during the interaction with offices software like the Microsoft® Office 2003.

Virtual reality in the study of warnings effectiveness

Warnings are a very important method to control hazards and to promote safety. Despite its importance, warnings have important gaps that limit their validity and make its design so difficult. In this sense, warnings effectiveness evaluation is crucial to guarantee effective people safety. However, warnings traditional evaluation methodologies have several limitations. To this extent, the main purpose of this work is to determine Virtual Reality (VR) ecological validity as a warnings evaluation technique. We describe a methodology that uses VR as a technique to evaluate safety signs. The main advantages of VR use, associated with the interaction level, are discussed.