This paper summarizes recent developments in audio and tactile feedback based assistive technologies targeting the blind community. Current technology allows applications to be efficiently distributed and run on mobile and handheld devices, even in cases where computational requirements are significant. As a result, electronic travel aids, navigational assistance modules, text-to-speech applications, as well as virtual audio displays which combine audio with haptic channels are becoming integrated into standard mobile devices. This trend, combined with the appearance of increasingly user-friendly interfaces and modes of interaction has opened a variety of new perspectives for the rehabilitation and training of users with visual impairments. The goal of this paper is to provide an overview of these developments based on recent advances in basic research and application development. Using this overview as a foundation, an agenda is outlined for future research in mobile interaction design with respect to users with special needs, as well as ultimately in relation to sensor-bridging applications in general.

3D virtual reality spaces, whether running on desktop environments or on immersive displays, have been noted to support a radically new and highly stimulating way of working with digital content in a variety of application domains. At the same time, research in recent decades has produced a number of experimental results showing that the use of 3D, as opposed to 2D interfaces, can lead to performance improvements from a wide range of aspects, including the ability to comprehend and retain knowledge, ability to work collaboratively in more creative and effective ways, and ability to carry out workflows integrating numerous sources of information in less time. In this paper, we first review the relevant literature; then, we describe an exploratory study that we carried out with test subjects, both in a 3D desktop virtual environment and in a 2D web-based environment, while collecting eye tracking data. In the study, subjects were presented with a set of multimedia content on a range of topics within the field of astronomy, based on which they were subsequently asked to fill out a set of questionnaires. By comparing the 2D and 3D cases in terms of correctness of answers, time taken to perform the task, pupil dilation measurements, subjects’ self-reported difficulty assessments, as well as various kinds of high-level interaction patterns employed during the task (in 3D), we were able to identify a set of descriptive markers which may be relevant to the prediction of users’ effectiveness in virtual reality workspaces. In a weaker sense, the results also seem to support previous research works claiming improved effectiveness in 3D spaces compared to 2D web-based interfaces, although further work is needed to more clearly identify the constraints within which such benefits can be guaranteed.

In this paper, we propose a new virtual reality (VR) concept referred to as ‘context control’, which we use to describe VR workspaces that are dynamically reconfigurable based on the task at hand and the user’s individual learning and working style. To demonstrate the viability of the concept as well as how it could be applied in practical applications, we present an implementation framework that, at its foundations, relies on Kolb’s learning styles taxonomy, consisting of Assimilators, Accommodators, Convergers and Divergers. We propose a layout schema for each of these categories of learning style, and validate them based on an experiment involving 52 university students, showing that the test subjects preferred content layouts that represent cognitive profiles matching their own to a greater extent. We also propose a hierarchical schema template language with which the schemas can be formalized and made amenable to further dynamic customization.

Three-dimensional virtual reality (VR) environments, whether operating on desktop platforms or immersive screens, have been recognized for enabling novel and extremely engaging methods of interacting with digital content across various fields of application. Studies conducted over the past several years have also consistently suggested that utilizing 3D in contrast to 2D interfaces can lead to enhancements in multiple performance dimensions. These enhancements encompass better understanding and retention of information, increased capacity for inventive and efficient collaboration, and the ability to execute workflows that integrate numerous information sources more quickly. At the same time, how digital content such as documents, audio–visual content and web browsers are integrated into 3D spaces is often decided by the creators of the spaces based on either aesthetic considerations, or on a case-by-case basis depending on the workflow. In this paper, we present the results of an experiment we conducted to better understand how users prefer to arrange digital content in their 3D environments, depending on the subject matter, the format of the content (e.g., text-based, image, or audio–visual) and the 3D objects within the space. The results of the experiment presented in the paper can help inform future 3D VR design methodologies and may also provide support for automated content arrangement solutions.

Object categorization and recognition have proved to be difficult tasks in artificial intelligence for several decades. With the recent emergence of biologically inspired soft-computing methods, promising results in specialized application domains are more and more common. In this paper, we propose a novel object categorization method based on statistical properties of nodes -derived from the VFA model -and hierarchical temporal memories. A referential categorization method, obtained by feeding grayscale pixel levels to hierarchical temporal memories, is used to evaluate the model's performance. Results show that categorization based on the statistics of nodes seems to yield higher success rates. This is in correspondence with Biederman's conjecture in his theory of recognition by components (RBC), according to which the statistics of nodes, end points and corners carry essential and sufficient information for object recognition [1]. The first section of this paper consists of a brief introduction, in which we restate the formal definition of the VFA model, as well as present its node-filtering applications. This will be followed by a presentation of the HTM theory for size-and orientation-invariant object representation. Finally, we give a detailed case study in which a hierarchical temporal memory is used to distinguish between two, as well as several object categories.

Virtual reality (VR) is a powerful technological framework that can be considered as comprising any kind of device that allows for 3D environments to be simulated and interacted with via a digital interface. Depending on the specific technologies used, VR can allow users to experience a virtual world through their different senses, i.e., most often sight, but also through touch, hearing, and smell. In this paper, it is argued that a key impediment to the widespread adoption of VR technology today is the lack of interoperability between users’’ existing digital life (including 2D documents, videos, the Web, and even mobile applications) and the 3D spaces. Without such interoperability, 3D spaces offered by current VR platforms seem empty and lacking in functionality. In order to improve this situation, it is suggested that users could benefit from being able to create dashboard layouts (comprising 2D displays) for themselves in the 3D spaces, allowing them to arrange, view and interact with their existing 2D content alongside the 3D objects. Therefore, the objective of this research is to help users organize and arrange 2D content in 3D spaces depending on their needs. To this end, following a discussion on why this is a challenging problem—both from a scientific and from a practical perspective—a set of operations are proposed that are meant to be minimal and canonical and enable the creation of dashboard layouts in 3D. Based on a reference implementation on the MaxWhere VR platform, a set of experiments were carried out to measure how much time users needed to recreate existing layouts inside an empty version of the corresponding 3D spaces, and the precision with which they could do so. Results showed that users were able to carry out this task, on average, at a rate of less than 45 s per 2D display at an acceptably high precision.