Catálogo de publicaciones - libros

This paper presents a walkthrough evaluation method for assessing, in a Universal Access perspective, interactive systems. The methodology is an adaptation of the traditional cognitive walkthrough used for many years in the usability engineering community. Cognitive walkthrough involves a simulation of the of an , to ensure that the user can easily learn to perform tasks that the system is indented to support. The proposed method, described here in brief along with the underlying theoretical framework, extends this approach by: (a) involving a simulation of the users’ reasoned action process, to ensure that users will be in favour of accessing, exploring, utilising, and, ultimately, adopting the system; (b) addressing the diverse needs of all users, rather than of the average user, thus incorporating accessibility for all target users as an intrinsic measurement. A set of printed forms with specific questions reflecting the proposed methodology has been developed to guide the new walkthrough procedure. Early experiences with the application of the method in the domain of eServices are also discussed.

Context-awareness is an important capability needed in devices in a ubiquitous computing environment. Ubiquitous computing devices use different types of sensors along with the user’s interaction history in order to collect and store data. This data is then used to adapt the user’s behavior to suit the current environment. In addition to the explicit modifications by user control, the behavior of these computing devices along with the interaction amongst one another depends on the continuously changing environment conditions. These characteristics require the development of systems that have both, adaptive and an adaptable nature. Context-awareness is particularly important for physically handicapped people. This is due to the fact that context-aware ubiquitous devices are able to help them detect changes in the surrounding, which handicapped people can not do for themselves. In this research paper we suggest a general architecture of Context-Aware Adaptable System (CAAS). We exemplify this architecture with an Ambient Service prototype that we have developed.

In recent years, projectors are undergoing a transformation as they evolve from static output devices to portable, or communication systems. However, the projection images appear distorted unless the projector is precisely aligned to the projection screen. Generally many projection-based systems are corrected for oblique projection distortion using calibration methods (e.g., warping function). Computing a warping function uses fiducials or a special pattern projected to the screen. These methods are unable to automatically calibrate in real-time especially when a projector is moving. In this paper, we proposed an automatic calibration system in real-time. Our system makes up of a function to correct images that are only based on the degree angle of a mirror set up in front of the projector without attaching fiducials to the screen. Therefore the system can be used to display regardless of screen condition in parallelepiped room. This operation process is very simple and fast. Therefore our system provides a function of correcting movies during the movement of the projector (27.3fps). An advantage of the proposed method is the system can be easily applied to ubiquitous computing like interactive presentation or game.

There is a consensus on the significance and high contribution of user involvement in the process of user interfaces development. However, there is no standard way to implement user involvement in software development processes. Dealing with speech-based interfaces that involve vocal interaction of speaking and hearing, the need of user involvement is increased. In this paper, we focus on the characteristics of speech interface development and suggest a user-based method that enables continuous user evaluation. We illustrate the method implementation in two different software projects that contain speech interfaces.

This paper describes an approach to use virtual reality technology and motion capturing for the immersive teaching of virtual humans. A combination of direct and indirect interaction as well as 2D list style menus and 3D dialogs has been realized to simplify the teaching process. In contrast to existing desktop solutions the presented concept allows even inexperienced users to reasonable work with the system. The interaction principles support an iterative work flow which speeds up the ergonomic evaluation and improvement of industrial work places remarkable.

This paper presents guidelines for the design of self-administered surveys for visually impaired and blind people within a mixed mode approach. The different needs of the target group are fulfilled by offering different modes of participation (paper-based, braille-based, Web-based). Reading aids have in common that they enhance the focus of a specific piece of text or single word. This advantage turns into a disadvantage in terms of a clear overview and arrangement of the text elements on a page. Therefore text needs to be designed with cognitive processes and accessibility standards in mind. This is especially true for a survey questionnaire where each question and answer item has to convey its own special meaning independent from context. Design problems and their solutions are described and illustrated with experiences from pretesting and a case study.

The Tile Dreamer is an integrated tool for creating and managing tiles, being two dimensional recurring constituent components of commonly deployed in structuring tile-based game terrains. The application consists of four basic subsystems: (a) the main tile editor for constructing tiles; (b) the bitmap ripper, automatically computing the least number of tiles for any given bitmap; (c) the connectivity checker, to test how tiles actually fit together to form larger regions; and (d) the tile bitmap builder, to put together a final set of tiles as a single bitmap. We discuss how the design of game tiles through the Tile Dreamer tool becomes easier and more efficient.

Lab Usability Tests show a series of inherent shortcomings that are attributable in essence to the artificial lab situation. This article informs about the reasons for developing a specific Remote Testing approach and describes how this measure helps to avoid such deficits. Subsequently, we will introduce the approach as well as two evaluation studies that assess the result quality of a Remote and a Lab Test within the context of online shopping.

User authentication is necessary for proving and verifying the claimed identity of users in a distributed environment. Three factors such as user’s knowledge, belongings, and biometric traits are usually considered for the purpose. A sort of multi-factor authentication may combine those factors in the way that a user provides the requested multi-factors separately, for improving the accuracy and security of authentication. However, such a combination of distinct factors should require each different human-computer interfaces. In this short paper, rather we introduce our on-going work to associate knowledge-based authentication with biometrics for requiring less interfaces and examine the benefits expected from it in a conceptual level.

Traditionally, evaluations for accessibility have been user-centered, based on guidelines and standards that are also user-centered. An argument is made for putting the needs of developers and programmers at the center of any accessibility evaluation process. Current practice in industry is briefly considered, including the roles of accessibility consultants as well as people in accessibility program offices in large companies. Their interactions with website and software application developers in the product development context is described. A project aimed at understanding developers as ’users’ of universal access guidance is introduced. This project focuses on the decisions that people involved with software programming and website development make with regards to disability access issues. The rationale and methodology for the project are introduced, and a three-stage process looking at past and current events; interview studies of consultants and product developers; and observational studies of decision making with respect to universal access.