Personal ICT Ensembles and Ubiquitous Information Systems Environments: Key Issues and Research Implications

Personal information and communication technologies (ICTs) have become commonplace. Today many people own, or have access to, a range of different computing and communication devices, information technologies, and services, which they incorporate into their everyday routines. Increasingly, these technologies impact the way that individuals work, socialize, and play. Workers are bringing their personal ICTs to the office, and organizations are tailoring their computing environments toward ubiquitous integration with personal ICTs. These developments are opening up new ways of working, but they also create new challenges for organizations in accommodating this “nonaffiliated” use as part of their information systems environments. In this article we propose a framework for analyzing the composition and impact of personal ICT ensembles. The framework is positioned as pre-theory that invites further development and empirical testing. We illustrate how the proposed framework could be applied to consider personal ICT use across the work/home context. Several implications stemming from the notion of a personal ICT ensemble are highlighted, including practical considerations for nonaffiliated use in organizations. We conclude with suggestions for further development of the proposed framework.

Ubiquitous multicore (UM) methodology for multimedia

For more than a decade now, multimedia developers have usually "ride the waves", so to speak, with the coming of each generation of microprocessors, which allows their applications, designs and programs to usually running more proficiently, efficiently and effectively. This so-called "free" ride seems to be coming to an end, with results of increases clock speeds, the widening of the gap in processor and memory performance, and the tradeoffs that are needed to meet the former two points, with the new multi-core systems. In this paper, we build upon our previous work within multi-core systems, by proposing a ubiquitous multi-core (UM) design. The goal of such a framework is help researchers to plan and implement their multimedia applications so they can take advantage of speed up computations of multi-core systems and allow real-time multimedia. As our experiments show, our UM system increases performance speeds at an average of 100%, with the average execution cost of 1.4ms, showing that multimedia can use multi-core resources efficiently and effectively.

Revisiting social influence in the ubiquitous computing era

This paper revisits the social influence construct in the era of ubiquitous computing. Despite its rather broad origins in psychology, social influence has to date been operationalized rather narrowly in the information technology adoption literature. We report on a study of mobile technology users in which we studied various social influences on these individuals. We isolate four distinct variants of social influence, operating in both inbound and outbound directions, each with positive and negative impacts. The study integrates three different dimensions of social influence into an analytical framework to facilitate future research. © 2012 IEEE.

Rapid prototyping of ubiquitous computing environments

Ubiquitous computing raises new usability challenges that cut across design and development. We are particularly interested in environments enhanced with sensors, public displays and personal devices. How can prototypes be used to explore the users' mobility and interaction, both explicitly and implicitly, to access services within these environments? Because of the potential cost of development and design failure, these systems must be explored using early assessment techniques and versions of the systems that could disrupt if deployed in the target environment. These techniques are required to evaluate alternative solutions before making the decision to deploy the system on location. This is crucial for a successful development, that anticipates potential user problems, and reduces the cost of redesign. This thesis reports on the development of a framework for the rapid prototyping and analysis of ubiquitous computing environments that facilitates the evaluation of design alternatives. It describes APEX, a framework that brings together an existing 3D Application Server with a modelling tool. APEX-based prototypes enable users to navigate a virtual world simulation of the envisaged ubiquitous environment. By this means users can experience many of the features of the proposed design. Prototypes and their simulations are generated in the framework to help the developer understand how the user might experience the system. These are supported through three different layers: a simulation layer (using a 3D Application Server); a modelling layer (using a modelling tool) and a physical layer (using external devices and real users). APEX allows the developer to move between these layers to evaluate different features. It supports exploration of user experience through observation of how users might behave with the system as well as enabling exhaustive analysis based on models. The models support checking of properties based on patterns. These patterns are based on ones that have been used successfully in interactive system analysis in other contexts. They help the analyst to generate and verify relevant properties. Where these properties fail then scenarios suggested by the failure provide an important aid to redesign.

Ubiquitous Computing: Any Ethical Implications?

In this article, the authors investigate, from an interdisciplinary perspective, possible ethical implications of the presence of ubiquitous computing systems in human perception/action. The term ubiquitous computing is used to characterize information-processing capacity from computers that are available everywhere and all the time, integrated into everyday objects and activities. The contrast in approach to aspects of ubiquitous computing between traditional considerations of ethical issues and the Ecological Philosophy view concerning its possible consequences in the context of perception/action are the underlying themes of this paper. The focus is on an analysis of how the generalized dissemination of microprocessors in embedded systems, commanded by a ubiquitous computing system, can affect the behaviour of people considered as embodied embedded agents.

Steady-state function of the ubiquitous mammalian Na/H exchanger (NHE1) in relation to dimer coupling models with 2Na/2H stoichiometry

We describe the steady-state function of the ubiquitous mammalian Na/H exchanger (NHE)1 isoform in voltage-clamped Chinese hamster ovary cells, as well as other cells, using oscillating pH-sensitive microelectrodes to quantify proton fluxes via extracellular pH gradients. Giant excised patches could not be used as gigaseal formation disrupts NHE activity within the patch. We first analyzed forward transport at an extracellular pH of 8.2 with no cytoplasmic Na (i.e., nearly zero-trans). The extracellular Na concentration dependence is sigmoidal at a cytoplasmic pH of 6.8 with a Hill coefficient of 1.8. In contrast, at a cytoplasmic pH of 6.0, the Hill coefficient is <1, and Na dependence often appears biphasic. Results are similar for mouse skin fibroblasts and for an opossum kidney cell line that expresses the NHE3 isoform, whereas NHE1(-/-) skin fibroblasts generate no proton fluxes in equivalent experiments. As proton flux is decreased by increasing cytoplasmic pH, the half-maximal concentration (K(1/2)) of extracellular Na decreases less than expected for simple consecutive ion exchange models. The K(1/2) for cytoplasmic protons decreases with increasing extracellular Na, opposite to predictions of consecutive exchange models. For reverse transport, which is robust at a cytoplasmic pH of 7.6, the K(1/2) for extracellular protons decreases only a factor of 0.4 when maximal activity is decreased fivefold by reducing cytoplasmic Na. With 140 mM of extracellular Na and no cytoplasmic Na, the K(1/2) for cytoplasmic protons is 50 nM (pH 7.3; Hill coefficient, 1.5), and activity decreases only 25% with extracellular acidification from 8.5 to 7.2. Most data can be reconstructed with two very different coupled dimer models. In one model, monomers operate independently at low cytoplasmic pH but couple to translocate two ions in "parallel" at alkaline pH. In the second "serial" model, each monomer transports two ions, and translocation by one monomer allosterically promotes translocation by the paired monomer in opposite direction. We conclude that a large fraction of mammalian Na/H activity may occur with a 2Na/2H stoichiometry.