15315903
An Evaluation of Techniques for Browsing Photograph Collections on Small Displays
In this paper we evaluate techniques for browsing photographs on small displays. We present two new interaction techniques that replace conventional scrolling and zooming controls. Via a single user action, scrolling and zooming are inter-dependently controlled with AutoZoom and independently controlled with GestureZoom. Both techniques were evaluated in a large-scale, 72-subject usability experiment alongside a conventional thumbnail grid image browser. Performance with the new techniques was at least as good as that with the standard thumbnail grid, even though none of the subjects had prior experience with such systems. In a number of cases – such as finding small groups of photos or when seeking for images containing small details – the new techniques were significantly faster than the conventional approach. In addition, AutoZoom and GestureZoom supported significantly more accurate identification of subsets of photographs. Subjects also reported lower levels of physical and cognitive effort and frustration with the new techniques in comparison to the thumbnail grid browser.
42586645
The music is the message
the music being played by her tiny mobile audio appliance. She's standing waiting for a train. Other commuters swarm nearby, headphones on, listening in more muted ways to the soundtracks they've chosen to accompany today's episode of their daily routine. Mobile music players—iPods, Walkmans and the like—are exciting for those of us involved in thinking about the future of mobile devices and services. Like the mobile phone—increasing numbers of which also sport a music player—these are gadgets that people actually desire, and aspire to own. They have vast storage capacities, increasingly sophisticated processors and pleasing, effective mechanisms for users to control their func-tionality. From click and jog wheels to high-resolution color displays, these players are far from being the impoverished devices that typified mobile platforms just a few years ago. And there are hundreds of millions of them in circulation—Apple sold five million in the first quarter of 2006 alone. But at the same time, these marvelous mobiles could be seen as an obstacle to the bright futures dreamt up in the research labs. How will people be able to make use of the ubiquitous computing infrastructure being envisaged, the anytime, everywhere access to information and services, when they are immersed in digital sound bubbles of their own choosing? Some mobile listeners, at first sight, certainly appear cut off. Another scene: A young man stares out of a train window, watching the long green fields flash by. His eyes are bright but still; his gaze betrays a mood of deep reflection. Listening to music on expensive , noise-reducing headphones, what is he thinking? Is he sadly contemplating a lover left or anticipating a longed-for meeting at his destination? How can we design mobile services that will fit this context? The conventional clumsy beeps, vibrations, and attention-seeking displays seem out of place. What opportunities are there to build more emphatic systems , systems to enhance the music and environmental experience or to provide ways for the listener to later reflect on the situations they've lived through in relation to the music they've heard? At other times, though, these sound bubbles seem more permeable, don't they? One of the photos of people listening to music available on a popular image-sharing site is entitled " Listening to Kim's iPod and talking to Joe! " A teenager holds a mobile phone to her left ear while wearing the distinctive white music-player headphones. Chatting and …
3268647
A digital library of conversational expressions: helping profoundly disabled users communicate
Digital libraries are for everyone. This paper describes the development of a digital library for a user who has a profound physical disability that means she cannot communicate verbally, and cannot use conventional communication tools.
39264003
HyperAT: HCI and Web Authoring
We review HCI problems with hypertext, and for authoring World Wide Web documents in particular. We suggest that a framework is required to understand the usability issues, and that these issues cannot be seen as psychological or computing: they are multi-disciplinary. We discuss HyperAT, a protorype authoring tool, being implemented to test these ideas.
22559047
Usability of digital libraries
3300534
Improving mobile internet usability
Mobile internet technologies, such as WAP, are important for pervasive, anytime, anywhere computing. Although much progress has been made in terms of technological innovation, many of mobile internet systems are difficult to use, lack flexibility and robustness. They give a poor user experience. Evaluation and theoretical analysis of usability combined with innovative design can achieve significant improvements in user performance and satisfaction. Using such multidisciplinary methods explains the negative reactions to WAP, and — more constructively — suggest ways of developing more effective and efficient devices and services.
41482626
A New Approach to the Construction of Surfaces from Contour Data
This paper presents a new approach to the construction of a surface from a stack of contour slices. Unlike most existing methods, this new approach handles ambiguous conditions consistently without employing an algorithm to establish a correspondence between vertices on one contour and those on the next. It is easy to implement and fast to compute, requiring only basic geometric properties, namely closedness and simplicity, to be available with contour data. The advantages of this new approach have also been demonstrated with solutions to a few classical problems from the literature and some practical problems in medical imaging. It can also be applied to geographical surveying and keyframe animations.
9085764
Distance Field Compression
This paper compares various techniques for compressing floating point distance fields. Both lossless and lossy techniques are compared against a new lossless technique. The new Vector Transform technique creates a predictor based upon a Vector Distance Transform and its suitability for distance field data sets is reported. The new technique produces a lossless encoding at a third of the file size of entropy encoders, and equivalent to lossy wavelet transforms, where around 75% of the coefficients have been set to zero. The algorithm predicts each voxel value linearly based upon two previous voxels chosen from one of 13 directions which have been previously computed. Those that cannot be predicted are explicitly stored.
43107545
A Theory of Qualified Types
Abstract This paper describes a general theory of overloading based on a system of qualified types. The central idea is the use of predicates in the type of a term, restricting the scope of universal quantification. A corresponding semantic notion of evidence is introduced and provides a uniform framework for implementing applications of this system, including Haskell style type classes, extensible records and subtyping. Working with qualified types in a simple, implicitly typed, functional language, we extend the Damas-Milner approach to type inference. As a result, we show that the set of all possible typings for a given term can be characterized by a principal type scheme, calculated by a type inference algorithm.
14632058
First-class polymorphism with type inference
Languages like ML and Haskell encourage the view of values as first-class entities that can be passed as arguments or results of functions, or stored as components of data structures. The same languages offer parametric polymorphism, which allows the use of values that behave uniformly over a range of different types. But the combination of these features is not supported-- polymorphic values are not first-class. This restriction is sometimes attributed to the dependence of such languages on type inference, in contrast to more expressive, explicitly typed languages, like System F, that do support first-class polymorphism.This paper uses relationships between types and logic to develop a type system, FCP, that supports first-class polymorphism, type inference, and also first-class abstract datatypes. The immediate result is a more expressive language, but there are also long term implications for language design.
22331464
Vector-City Vector Distance Transform
This paper will examine the current chamfer and vector distance transforms for encoding objects as distance fields. A new vector distance transform is introduced which uses the city-block chamfer distance transform as a basis. Detailed error analysis using real CT data is presented, demonstrating the improved accuracy of the new approach over existing methods. The production of a subvoxel accurate distance field is also demonstrated by employing an improved classification. Distance fields are shown for skull and chess piece datasets.