The Optimisation of Stochastic Grammars to Enable Cost-Effective Probabilistic Structural Testing

The effectiveness of probabilistic structural testing depends on the characteristics of the probability distribution from which test inputs are sampled at random. Metaheuristic search has been shown to be a practical method of optimis- ing the characteristics of such distributions. However, the applicability of the existing search-based algorithm is lim- ited by the requirement that the software’s inputs must be a fixed number of numeric values. In this paper we relax this limitation by means of a new representation for the probability distribution. The repre- sentation is based on stochastic context-free grammars but incorporates two novel extensions: conditional production weights and the aggregation of terminal symbols represent- ing numeric values. We demonstrate that an algorithm which combines the new representation with hill-climbing search is able to effi- ciently derive probability distributions suitable for testing software with structurally-complex input domains

Using Design Fiction to Inform Shape-Changing Interface Design and Use

Shape-changing interfaces are tangible, physically dynamic devices which enable user-experience beyond 2D screens. Within Human Computer Interaction, researchers are developing these from low-resolution, low-fidelity prototypes, toward a vision of a truly malleable world. The main focus is in producing and testing hardware, and basic user interactions, which leaves the question unanswered: what are shape-changing interfaces good for? In response, we propose the use of design fiction to investigate potential applications for this technology: to create and analyse artifacts relating to future use-scenarios for shape-change. Whilst research within shape-change often proposes future use-cases for prototypes during discussion, they are seldom in a form that presents them as everyday artifacts. Here, we present and discuss a printed game-play instruction manual for a truly high resolution shape-changing game entitled First Hand, which aims to draw parallels between current gaming practices and the tangible nature of shape-changing interfaces

Using Design Fiction to Inform Shape-Changing Interface Design and Use

Shape-changing interfaces are tangible, physically dynamic devices which enable user-experience beyond 2D screens. Within Human Computer Interaction, researchers are developing these from low-resolution, low-fidelity prototypes, toward a vision of a truly malleable world. The main focus is in producing and testing hardware, and basic user interactions, which leaves the question unanswered: what are shape-changing interfaces good for? In response, we propose the use of design fiction to investigate potential applications for this technology: to create and analyse artifacts relating to future use-scenarios for shape-change. Whilst research within shape-change often proposes future use-cases for prototypes during discussion, they are seldom in a form that presents them as everyday artifacts. Here, we present and discuss a printed game-play instruction manual for a truly high resolution shape-changing game entitled First Hand, which aims to draw parallels between current gaming practices and the tangible nature of shape-changing interfaces

A survey of pervasive displays for information presentation

Weiser’s seminal vision of ubiquitous computing had calm information presentation at its heart and identified an important challenge in providing pervasive yet unobtrusive information display while avoiding problems of information overload. Since this vision was first articulated, a range of approaches have emerged for presenting information on pervasive displays and digital screens of varying sizes are now an everyday feature of our environments. Such displays provide significant opportunities for presenting information in-situ to support users in a range of activities, and the growing expectation is that there is constant peripheral access to digital information. In this article we review three different pervasive display technologies used for information presentation: traditional 2D display media, urban media facades, and novel display hardware. Our survey identifies five emerging trends that cross all three technologies: an increasing focus on situatedness, a movement towards non-expert users, growing demand for accessible interaction, a potential for new applications of data, and a difficulty in balancing ‘calm’ computing against presentation of data at an appropriate granularity and complexity

Gaze+touch vs. touch: what’s the trade-off when using gaze to extend touch to remote displays?

Direct touch input is employed on many devices, but it is inherently restricted to displays that are reachable by the user. Gaze input as a mediator can extend touch to remote displays - using gaze for remote selection, and touch for local manipulation - but at what cost and benefit? In this paper, we investigate the potential trade-off with four experiments that empirically compare remote Gaze+touch to standard touch. Our experiments investigate dragging, rotation, and scaling tasks. Results indicate that Gaze+touch is, compared to touch, (1) equally fast and more accurate for rotation and scaling, (2) slower and less accurate for dragging, and (3) enables selection of smaller targets. Our participants confirm this trend, and are positive about the relaxed finger placement of Gaze+touch. Our experiments provide detailed performance characteristics to consider for the design of Gaze+touch interaction of remote displays. We further discuss insights into strengths and drawbacks in contrast to direct touch

Sketch & The Lizard King: Supporting Image Inclusion in HCI Publishing

Almost all research output includes tables, diagrams, photographs and even sketches, and papers within HCI typically take advantage of including these figures in their files. However the space given to non-diagrammatical or tabular figures is often small, even in papers that primarily concern themselves with visual output. The reason for this might be the publishing models employed in most proceedings and journals: Despite moving to a digital format which is unhindered by page count or physical cost, there remains a somewhat arbitrary limitation on page count. Recent moves by ACM SIGCHI and others to remove references from the maximum page count suggest that there is movement on this, however images remain firmly within the limits of the text. We propose that images should be celebrated – not penalised – and call for not only the adoption of the Pictorials format in CHI, but for images to be removed from page counts in order to encourage greater transparency of process in HCI research

Neuromuscular control and running economy is preserved in elite international triathletes after cycling

Running is the most important discipline for Olympic triathlon success. However, cycling impairs running muscle recruitment and performance in some highly trained triathletes; though it is not known if this occurs in elite international triathletes. The purpose of this study was to investigate the effect of cycling in two different protocols on running economy and neuromuscular control in elite international triathletes. Muscle recruitment and sagittal plane joint angles of the left lower extremity and running economy were compared between control (no preceding cycle) and transition (preceded by cycling) runs for two different cycle protocols (20-minute low-intensity and 50-minute high-intensity cycles) in seven elite international triathletes. Muscle recruitment and joint angles were not different between control and transition runs for either cycle protocols. Running economy was also not different between control and transition runs for the ow-intensity (62.4 ^ 4.5 vs. 62.1 ^ 4.0 ml/min/kg, p . 0.05) and high-intensity (63.4 ^ 3.5 vs. 63.3 ^ 4.3 ml/min/kg, p . 0.05) cycle protocols. The results of this study demonstrate that both low- and high-intensity cycles do not adversely influence neuromuscular control and running economy in elite international triathletes.<br /

Time for a Change:Examining Temporality in Shape-Changing Interfaces

The development of dynamic, shape-changing interfaces as a method of human-computer interaction is receiving increasing attention in both research and manufacturing. The present focus is mainly on hardware development, rather than potential applications. To advance this area, considering temporality in shape-changing displays and interfaces is vital in understanding how to design applications for (and with) such devices. Prototypes within the field range from those which actuate changes at high speed, to the deliberately slow, with a complex range of temporal movement in between. Current research highlights the importance of temporal form in interaction design, and expressive movement, but this is yet to be applied in detail to shape-change. This paper examines the current state of play for temporality in shape-changing interfaces, examines the role of time and design in existing prototypes, and proposes an adaptive methodology for design utilising time, space and shape based on previous research

Toward a Practice of User-Centred Design for Shape-Changing Interfaces

Shape-changing User Interfaces (UIs) are maturing in application and complexity, and therefore are becoming a tangible reality with regards to commercialization and design in a wider context. Current prototypes support a variety of bespoke interactions and are extensively tested, but applications for these constructs are often limited to the research scenario, and within the limitations of academic institutions. Engaging with a wider audience to develop novel UIs and applications is a valuable addition to the early design process, and can elicit new directions for research. Additionally, focusing on the user fulfils a requirement for developing a User-Centred Design methodology for shape-change, as it presents novel challenges for interaction design. This position paper calls for early adoption of such processes to support the emerging technology of shape-change, and for the formation of a collaborative UCD working group in this field

FingerSlide: Investigating Passive Haptic Sliding As A Tacton Channel

The haptic sensation of sliding a surface under a probing finger can be used to convey surface information or coded data to the user. In this paper, we investigate users' ability to discern different sliding profiles based on the velocity and direction of sliding for use as haptic-tactons. We built FingerSlide, a novel haptic device which can position and control moving surfaces under a user's finger and used this to run two independent studies. The first study investigates if users can identify the direction of sliding at different velocities. The second study investigates if the users can distinguish a difference between two velocities. Our results show a faster response for higher velocities in the direction study and high error rates in identifying differences in the direction study. We discuss these results and infer design considerations for haptic devices that use the sliding effect to convey information