Andreas Lorenz

An operational definition of context

The definition of context experienced an evolution in the research area of context-aware computing, but still suffers from either generality or incompleteness. Furthermore, many definitions are driven by the ease of implementation. This paper introduces two extensions to available context definitions that provide a natural understanding of this concept to users of context-aware applications and facilitates the engineering of this concept for software developers of such applications.

Personalization and Context Management

Supporting the individual user in his working, learning, or information access is one of the main goals of user modeling. Personal or group user models make it possible to represent and use information about preferences, knowledge, abilities, emotional states, and many other characteristics of a user to adapt the user experience and support. Nowadays, the disappearing computer enables the user to access her information from a variety of personal and public displays and devices. To support a new generation of contextualized and personalized information and services, this paper addresses the problem of context management. Context management is a new approach to the design of context-aware systems in ubiquitous computing that combines personalization and contextualization. The presented framework for context management integrates user modeling and context modeling, which can benefit from each other and give rise to more valid models for personalized and contextualized information delivery. The paper will introduce a base framework and tools for designing context-aware applications and decompose the underlying framework into its foundational components. As two illustrative application cases, the paper discusses implementations of an intelligent advertisement board and an audio-augmented museum environment.

Fast track article: Mobile health monitoring for the elderly: Designing for diversity

In the field of mobile health monitoring the current most important user groups are those aged 50 +. In our project senSAVE^(R) we developed a user interface for monitoring vital personal parameters that is specifically adapted to the needs of this group. The group is said to show less perception and control capability and has less experience in the use of information technology. More realistically, the group of 50 + users shows more diversity in their cognitive, sensory and motor skills than younger people. User interfaces for elderly people should therefore be designed for different capabilities and needs. For a mobile health monitoring system three design types were developed and evaluated in this study: three basic interfaces, two professional interfaces and an interface in between as a compromise of the two former types. Beyond monitoring the vital parameters of the user during mobile phases a stationary module for the inspection of aggregated data was included on a standard TV set together with a remote control device. The paper describes the user interface design and a comparative evaluation of the interfaces during and after the development, i.e. formative and summative evaluation. It also describes first user feedback about the stationary component.

LISTEN: a user-adaptive audio-augmented museum guide

Modern personalized information systems have been proven to support the user with information at the appropriate level and in the appropriate form. In specific environments like museums and exhibitions, focusing on the control of such a system is contradictory to establishing a relationship with the artifacts and exhibits. Preferably, the technology becomes invisible to the user and the physical reality becomes the interface to an additional virtual layer: by naturally moving in the space and/or manipulating physical objects in our surroundings the user will access information and operate the virtual layer. The LISTEN project is an attempt to make use of the inherent “everyday” integration of aural and visual perception, developing a tailored, immersive audio-augmented environment for the visitors of art exhibitions. The challenge of the LISTEN project is to provide a personalized immersive augmented environment, an aim which goes beyond the guiding purpose. The visitors of the museum implicitly interact with the system because the audio presentation is adapted to the users’ contexts (e.g. interests, preferences, motion, etc.), providing an intelligent audio-based environment. This article describes the realization and user evaluation of the LISTEN system focusing on the personalization component. As this system has been installed at the Kunstmuseum Bonn in the context of an exhibition comprising artworks of the painter August Macke, a detailed evaluation could be conducted.

Personalized mobile health monitoring for elderly

The key for successfully deploy mobile applications is the ability to understand the specific needs of its customers. In the field of mobile health monitoring, the currently most important user group is the group of persons of the age 50+. In our project senSAVE® we developed a user interface for monitoring personal vital parameters that is specifically adapted to the needs of this group. The paper illustrates our work to ensure usability of the application and the outcome of the project.

Using handheld devices for mobile interaction with displays in home environments

An increasing number of households are equipped with a large number of TV sets and more and more of them are large highresolution displays. Furthermore, we see the integration of web browsing and email functionalities in these devices, which are then often controlled via a wireless mouse and keyboard. The latter were rather designed for the usage on a desk, rather then by a person sitting on their sofa in a living room. Therefore, this paper investigates the usage of a PDA, as a replacement which can be used for controlling a remote cursor and for text input. The results of the experimental comparison of these input devices show, as expected, the superiority of mouse and keyboard (as the study participants were very experienced with them). Surprising results were the task completion time and usability satisfaction when using the mobile device. These results show the applicability of using a mobile device for controlling an application on a remote screen. Using a mobile device provides the advantages that every person can e.g. use their own mobile phone or that these devices can be used in multi-user scenarios.

Applications of a context-management system

In ubiquitous computing, the user will be interrupted in performing a task only if the information is relevant to the task or highly important in the situation to justify the interrupt. The information selection and presentation therefore should be adapted to the user and his current context of use. Nowadays, uncounted Content-Management Systems provide access to a large amount of information, but without context, information is just data. This paper introduces Context-Management as a new approach for the design of context-aware systems in ubiquitous computing. As a proof of concept we illustrate three prototypical implementations of contextualized information systems in different applications domains and decompose the underlying framework into its foundational components.

User modeling in adaptive audio-augmented museum environments

The paper illustrates approaches for making audio-augmented museum environments adaptive. Based on well-known user modeling techniques we present a combination of suitable components that adapt audio information to the interests, preferences and motion of a museums visitor. The underlying environment, i.e. the carrier and transmitter of information, is provided by the LISTEN system, which enables the augmentation of everyday environments with audio information.

Agent-Based ubiquitous user modeling

The main objective of the thesis is to define and implement a framework for agent-based distributed user-modeling. This paper introduces the approach for applying agent technology and illustrates the research issues in distributing the knowledge about the user among active entities, and distributed user-model acquisition and application methods.

The ambient media player: a media application remotely operated by the use of mobile devices and gestures

To utilize interactive multimedia applications in public and private environments for advertisement, entertainment and user guidance requires remote input capabilities. The use of mobile and handheld devices is a desirable option for implementation of user interaction with remote services from a distance. Another prominent option to operate a remote application is the use of gestures performed in the air. This paper describes the design and realization of a media-player application to run in the environment of the user. A small qualitative user study verified the use of mobile phones, switching between three input modalities, and the opportunity of another three methods of performing gestures in the air system to enable mobile devices and gesture recognition tools to control the application from the distance.