26,687 research outputs found
Recommended from our members
A first empirical study of direct combination in a ubiquitous environment
In dynamic ubiquitous environments, end users may need to create services by causing two or more devices or resources to interoperate together in ad-hoc circumstances. In general, users can find this kind of process hard to manage. At the same time, existing UI architectures are not well suited to supporting such activities. It is proposed that a good basis for addressing these and related problems in a principled, scaleable way is the principle of Direct Combination (DC). The principle is summarized, and analytical arguments are presented that predict that DC can reduce the amount of search required by the user. Other things being equal, such a reduction in search would be expected to offer interactions which are faster, less frustrating, and impose less mental load on the user. We present a proof-of-concept implementation, and a small-scale evaluation of a DC interface. Within the limitations of a preliminary evaluation, consistent support is offered across several measures for the analytical predictions
Context modeling and constraints binding in web service business processes
Context awareness is a principle used in pervasive services
applications to enhance their exibility and adaptability to
changing conditions and dynamic environments. Ontologies
provide a suitable framework for context modeling and reasoning. We develop a context model for executable business processes { captured as an ontology for the web services domain. A web service description is attached to a service context profile, which is bound to the context ontology. Context instances can be generated dynamically at services runtime and are bound to context constraint services. Constraint services facilitate both setting up constraint properties and constraint checkers, which determine the dynamic validity of context instances. Data collectors focus on capturing context instances. Runtime integration of both constraint services and data collectors permit the business process to achieve dynamic business goals
Social positioning: Designing the Seams between Social, Physical and Digital Space
Mobile settings are not only physically and digitally mediated; they are also inhabited by people - a social space. We argue that careful design exposing the connections, gaps, overlays and mismatches within and between physical, digital and social space allow for a better understanding and thereby mastering of the resulting combined space. Two concepts are explored in MobiTip, a social mobile service for exchanging opinions among peers: intramedia seams concerning network coverage and position technology, and intermedia seams between digitally transmitted tips and the physical, social context surrounding the user. We introduce social positioning as an alternative and complement to the current strive for seamless connectedness and exact positioning in physical space
Quality assessment technique for ubiquitous software and middleware
The new paradigm of computing or information systems is ubiquitous computing systems. The technology-oriented issues of ubiquitous computing systems have made researchers pay much attention to the feasibility study of the technologies rather than building quality assurance indices or guidelines. In this context, measuring quality is the key to developing high-quality ubiquitous computing products. For this reason, various quality models have been defined, adopted and enhanced over the years, for example, the need for one recognised standard quality model (ISO/IEC 9126) is the result of a consensus for a software quality model on three levels: characteristics, sub-characteristics, and metrics. However, it is very much unlikely that this scheme will be directly applicable to ubiquitous computing environments which are considerably different to conventional software, trailing a big concern which is being given to reformulate existing methods, and especially to elaborate new assessment techniques for ubiquitous computing environments. This paper selects appropriate quality characteristics for the ubiquitous computing environment, which can be used as the quality target for both ubiquitous computing product evaluation processes ad development processes. Further, each of the quality characteristics has been expanded with evaluation questions and metrics, in some cases with measures. In addition, this quality model has been applied to the industrial setting of the ubiquitous computing environment. These have revealed that while the approach was sound, there are some parts to be more developed in the future
A Role-Based Approach for Orchestrating Emergent Configurations in the Internet of Things
The Internet of Things (IoT) is envisioned as a global network of connected
things enabling ubiquitous machine-to-machine (M2M) communication. With
estimations of billions of sensors and devices to be connected in the coming
years, the IoT has been advocated as having a great potential to impact the way
we live, but also how we work. However, the connectivity aspect in itself only
accounts for the underlying M2M infrastructure. In order to properly support
engineering IoT systems and applications, it is key to orchestrate
heterogeneous 'things' in a seamless, adaptive and dynamic manner, such that
the system can exhibit a goal-directed behaviour and take appropriate actions.
Yet, this form of interaction between things needs to take a user-centric
approach and by no means elude the users' requirements. To this end,
contextualisation is an important feature of the system, allowing it to infer
user activities and prompt the user with relevant information and interactions
even in the absence of intentional commands. In this work we propose a
role-based model for emergent configurations of connected systems as a means to
model, manage, and reason about IoT systems including the user's interaction
with them. We put a special focus on integrating the user perspective in order
to guide the emergent configurations such that systems goals are aligned with
the users' intentions. We discuss related scientific and technical challenges
and provide several uses cases outlining the concept of emergent
configurations.Comment: In Proceedings of the Second International Workshop on the Internet
of Agents @AAMAS201
A framework for requirements engineering for context-aware services
Context-aware services, especially when made available
to mobile devices, constitute an interesting but very challenging
domain. It poses fundamental problems for both
requirements engineering, software architecture, and their
relationship. We propose a novel, reflection-based framework
for requirements engineering for this class of applications.
The framework addresses the key difficulties in this
field, such as changing context and changing requirements.
We report preliminary work on this framework and suggest
future directions
Semantic-based policy engineering for autonomic systems
This paper presents some important directions in the use of ontology-based semantics in achieving the vision of Autonomic Communications. We examine the requirements of Autonomic Communication with a focus on the demanding needs of ubiquitous computing environments, with an emphasis on the requirements shared with Autonomic Computing. We observe that ontologies provide a strong mechanism for addressing the heterogeneity in user task requirements, managed resources, services and context. We then present two complimentary approaches that exploit ontology-based knowledge in support of autonomic communications: service-oriented models for policy engineering and dynamic semantic queries using content-based networks. The paper concludes with a discussion of the major research challenges such approaches raise
Pervasive and standalone computing: The perceptual effects of variable multimedia quality.
The introduction of multimedia on pervasive and mobile communication devices raises a number of perceptual quality issues, however, limited work has been done examining the 3-way interaction between use of equipment, quality of perception and quality of service. Our work measures levels of informational transfer (objective) and user satisfaction (subjective)when users are presented with multimedia video clips at three different frame rates, using four different display devices, simulating variation in participant mobility. Our results will show that variation in frame-rate does not impact a userâs level of information assimilation, however, does impact a usersâ perception of multimedia video âqualityâ. Additionally, increased visual immersion can be used to increase transfer of video information, but can negatively affect the usersâ perception of âqualityâ. Finally, we illustrate the significant affect of clip-content on the transfer of video, audio and textual information, placing into doubt the use of purely objective quality definitions when considering multimedia
presentations
- âŠ