Showing papers by "Barbara Leporini published in 2009"

Vibrotactile feedback to aid blind users of mobile guides

Abstract: In this work, we report on a solution for providing support to the blind using mobile museum guides by exploiting the haptic channel as a complement to the audio/vocal one. The overall goal is to improve the autonomy and social integration of blind visitors. We followed an iterative approach in which the proposed system went through various user evaluations and further refinements. The final solution includes vibrotactile feedback enhancement for orientation and obstacle avoidance obtained through the use of unobtrusive actuators applied to two of the user's fingers combined with an electronic compass and obstacle detector sensors connected wirelessly to the mobile guide. Our study indicates that vibrotactile feedback is particularly useful to provide frequent unobtrusive indications of useful dynamic information, such as the level of proximity of an obstacle or the distance from the right orientation.

Accessing e-Learning Systems via Screen Reader: An Example

Abstract: The evolution of the Information and Communication Technology (ICT) and the rapid growth of the Internet have impelled the pervasive diffusion of e-Learning systems. This is a great opportunity for visually-disabled people provided that both the interactive environment, created by the Learning Management Systems, and the Learning Objects, created by teachers, are properly designed and delivered. In this paper we investigate interaction of the blind user with an open source Virtual Learning Environment (Moodle) and discuss how the use of the W3C Accessible Rich Internet Applications (ARIA) suite may improve the experience of navigation via screen reader.

Enriching web information scent for blind users

Abstract: Link annotation with the accessibility level of the target Web page is an adaptive navigation support technique aimed at increasing blind users' orientation in Web sites. In this work, the accessibility level of a page is measured by exploiting data from evaluation reports produced by two automatic assessment tools. These tools support evaluation of accessibility and usability guideline-sets. As a result, links are annotated with a score that indicates the conformance of the target Web page to blind user accessibility and usability guidelines. A user test with 16 users was conducted in order to observe the strategies they followed when links were annotated with these scores. With annotated links, the navigation paradigm changed from sequential to browsing randomly through the subset of those links with high scores. Even if there was not a general agreement on the correspondence between scores and user perception of accessibility, users found annotations helpful when browsing through links related to a given topic.

Book4All: A Tool to Make an e-Book More Accessible to Students with Vision/Visual-Impairments

Abstract: Empowering people who are blind or otherwise visually impaired includes ensuring that products and electronic materials incorporate a broad range of accessibility features and work well with screen readers and other assistive technology devices. This is particularly important for students with vision impairments. Unfortunately, authors and publishers often do not include specific criteria when preparing the contents. Consequently, e-books can be inadequate for blind and low vision users, especially for students. In this paper we describe a semi-automatic tool developed to support operators who adapt e-documents for visually impaired students. The proposed tool can be used to convert a PDF e-book into a more suitable accessible and usable format readable on desktop computer or on mobile devices.

Conceptual Framework: How to Engineer Online Trust for Disabled Users

Abstract: The Internet has penetrated our lives, becoming an indispensable tool for social, business and personal growth. Thanks to the Web, users can easily carry out many tasks that were previously difficult. Differently-abled persons need to have the same opportunities as everyone else, so accessibility and usability must be included in the design of all Web resources, applications and services. To be extensively applicable, accessibility and usability guidelines should be delivered as simple design features. In previous studies some conceptual frameworks have been introduced with this aim. However, the specific applicative environment such as trustworthy e-commerce services, may offer ad hoc challenges. In this paper, we propose some guidelines to extend the design of usability conceptual frameworks in order to promote trust in e-commerce websites for people with visual disabilities.

User Trust in eCommerce Services: Perception via Screen Reader

Abstract: The increasing diffusion of electronic commerce (eCommerce) services is a great opportunity for visually-disabled people, provided that accessible and usable interactive environments are available. Usually e-Commerce sites have complex layouts crowded with elements and are difficult to navigate via screen reader. Another crucial issue concerns consumer trust in security of on-line transactions. In this paper we investigate the interaction of blind users with eBay, a popular eCommerce website, with specific focus on accessibility and usability of secure transactions when navigating via screen reader.

Editing Wikipedia content by screen reader: easier interaction with the Accessible Rich Internet Applications suite.

Abstract: Purpose. This study aims to improve Wikipedia usability for the blind and promote the application of standards relating to Web accessibility and usability.Method. First, accessibility and usability of Wikipedia home, search result and edit pages are analysed using the JAWS screen reader; next, suggestions for improving interaction are proposed and a new Wikipedia editing interface built. Most of the improvements were obtained using the Accessible Rich Internet Applications (WAI-ARIA) suite, developed by the World Wide Web Consortium (W3C) within the framework of the Web Accessibility Initiative (WAI). Last, a scenario of use compares interaction of blind people with the original and the modified interfaces.Results. Our study highlights that although all contents are accessible via screen reader, usability issues exist due to the user's difficulties when interacting with the interface. The scenario of use shows how building an editing interface with the W3C WAI-ARIA suite eliminates many obstacles that can...

Usability and Accessibility of eBay by Screen Reader

Abstract: The evolution of Information and Communication Technology and the rapid growth of the Internet have fuelled a great diffusion of eCommerce websites. Usually these sites have complex layouts crowded with active elements, and thus are difficult to navigate via screen reader. Interactive environments should be properly designed and delivered to everyone, including the blind, who usually use screen readers to interact with their computers. In this paper we investigate the interaction of blind users with eBay, a popular eCommerce website, and discuss how using the W3C Accessible Rich Internet Applications (WAI-ARIA) suite could improve the user experience when navigating via screen reader.

Enhancing Wikipedia Editing with WAI-ARIA

Abstract: Nowadays Web 2.0 applications allow anyone to create, share and edit on-line content, but accessibility and usability issues still exist. For instance, Wikipedia presents many difficulties for blind users, especially when they want to write or edit articles. In a previous stage of our study we proposed and discussed how to apply the W3C ARIA suite to simplify the Wikipedia editing page when interacting via screen reader. In this paper we present the results of a user test involving totally blind end-users as they interacted with both the original and the modified Wikipedia editing pages. Specifically, the purpose of the test was to compare the editing and formatting process for original and ARIA-implemented Wikipedia user interfaces, and to evaluate the improvements.

Automatically Structuring Text for Audio Learning

Abstract: In recent years podcasting has been in great demand as a recreation and a learning tool. In this paper we describe the design and implementation of a system for automatically converting documents to structured audio. Our prototype is a Web-based service for preparing structured audio material to download on portable mp3 players. The on-line service is especially designed to aid users with special needs, such as the visually impaired. Ultimately, this would enhance comprehension for all.

Translating Museum Visual Contents into Descriptions for Blind Users: A Multidisciplinary Approach

Abstract: Accessibility and usability guidelines are available to design web sites accessible to blind users. However, the actual usability of accessible web pages varies depending on the type of information the user is dealing with. Museum web sites, including specimens and hall descriptions, need specific requirements to allow vision-impaired users, who navigate using a screen reader, to access pieces of information that are mainly based on visual perception. Here we address a methodology to be applied for the proper creation and elaboration of alternative image descriptions in museum web pages. Such methodology has been applied to a gallery of the Museum of Natural History and Territory (University of Pisa). Such indications allow the user: (1) to address indexed contents and to link to information in more details, (2) to calibrate image descriptions (with a command providing alternative explanations for specimens), and (3) to access extra information for the blind (via hidden labels). A multidisciplinary approach is necessary to obtain effective and comprehensive descriptions. In this perspective, a cooperative environment is eventually proposed for team work facilitation.

Improving Interaction via Screen Reader Using ARIA: An Example

Abstract: An interface that conforms to W3C ARIA (Accessible Rich Internet Applications) suite would overcome accessibility and usability problems that prevent disabled users from actively contributing to the collaborative growth of knowledge. In a previous phase of our study we first identified problems of interaction via screen reader with Wikipedia [2], then proposed an ARIA-based modified Wikipedia editing page [1]. At this stage we only focused on the main content for editing/formatting purposes (using roles). To evaluate the effectiveness of an ARIA-based formatting toolbar we only dealt with the main content of the editing page, not the navigation and footer sections. The next step using ARIA is to introduce landmarks (regions) and use the “flowto” property to be able to change the order of how page content is announced via screen reader. In this way the new UI becomes functionally equivalent to the original Wikipedia editing page and its appearance is very similar (apart from an additional combobox instead of a list of links), but usability is greatly enhanced. In this demo we will show the interaction via Jaws screen reader using both the original and the proposed Wikipedia editing pages.

Is Flash really accessible when interacting through screen readers

Abstract: In this paper we report on a study, which aims to assess whether the recent versions of Flash allow designers to obtain really accessible applications when users interact through screen readers. A Flash application has been analysed for this purpose along with various solutions for improving its accessibility. The results show that in some important cases Flash applications still raise important accessibility problems.