Jonathan P. Brezin

Improving web accessibility through an enhanced open-source browser

The accessibilityWorks project provides software enhancements to the MozillaTM, Web browser and allows users to control their browsing environment. Although Web accessibility standards specify markup that must be incorporated for Web pages to be accessible, these standards do not ensure a good experience for all Web users. This paper discusses user controls that facilitate a number of adaptations that can greatly increase the usability of Web pages for a diverse population of users. In addition to transformations that change page presentation, innovations are discussed that enable mouse and keyboard input correction as well as vision-based control for users unable to use their hands for computer input.

Towards a tool for keystroke level modeling of skilled screen reading

Designers often have no access to individuals who use screen reading software, and may have little understanding of how their design choices impact these users. We explore here whether cog-nitive models of auditory interaction could provide insight into screen reader usability. By comparing human data with a tool-generated model of a practiced task performed using a screen reader, we identify several requirements for such models and tools. Most important is the need to represent parallel execution of hearing with thinking and acting. Rules for placement of cogni-tive operators that were developed for visual user interfaces may not be applicable in the auditory domain. Other mismatches be-tween the data and the model were attributed to the extremely fast listening rate and differences between the typing patterns of screen reader usage and the models assumptions. This work in-forms the development of more accurate models of auditory inter-action. Tools incorporating such models could help designers create user interfaces that are well tuned for screen reader users, without the need for modeling expertise.

Human performance modeling for all: importing UI prototypes into cogtool

UI designers use a variety of prototyping tools, from paper and pencil sketching, to drag-and-drop mock-up tools (e.g., Balsamiq Mockups), to sophisticated suites of modeling tools and toolkits (e.g., iRise or dijit, the dojo GUI toolkit ). Many projects would benefit from quickly analyzing prototypes at an early stage without the effort of bringing in users for empirical tests. Most analysis tools, however (e.g., AutoCWW [1], Bloodhound [2], and CogTool [4]), require prototypes to be in their own format, which forces the designer to re-do the prototypes in order to analyze them. Our work is a step toward allowing the CogTool analysis tools to import from many different prototyping tools, so designers will have a path to quick usability analysis without changing the way they currently express their preliminary designs.

Toward modeling auditory information seeking strategies on the web

Human performance models based on information foraging theory have proved capable of predicting navigation behavior on the Web. They can therefore provide a useful tool for Web site design. They may also be effective for modeling auditory navigation within a single Web page. Designers often struggle to accommodate this sort of access, different as it is from their own experience. As a step toward realistic simulations based on models of auditory Web access, we describe information seeking strategies observed in people with visual impairment using screen reading software for Web navigation tasks. We outline one example strategy for approaching a new Web page that, guided by information foraging theory, may expose access barriers that current design tools miss.

Stable ergodicity in homogeneous spaces

AbstractIn this paper we prove that in the context of homogeneous spacesG/B which satisfy a certain admissibility requirement, stable ergodicity of an affine diffeomorphism implies that there is some hyperbolicity. Indeed,

Designing for auditory web access: accessibility and cellphone users

\overline {HB} = G

Common & particular needs: a challenge to participatory design

whereH is the hyperbolically generated subgroup ofG.

Optimization of system performance based on communication relationship

In 2002 DARPA (Defense Advanced Research Projects Agency) launched a major initiative in HPCS (high-productivity computing systems). The program was motivated by the belief that the utilization of the coming generation of parallel machines was gated by the difficulty of writing, debugging, tuning, and maintaining software at peta scale.