Future e-Health systems will consist of low-power on-body wireless sensors attached to mobile users that interact with an ubiquitous computing environment to monitor the health and well being of patients in hospitals or at home. Patients or health practitioners have very little technical computing expertise so these systems need to be self-configuring and self-managing with little or no user input. More importantly, they should adapt autonomously to changes resulting from user activity, device failure, and the addition or loss of services. We propose the Self-Managed Cell (SMC) as an architectural pattern for all such types of ubiquitous computing applications and use an e-Health application in which on-body sensors are used to monitor a patient living in their home as an exemplar. We describe the services comprising the SMC and discuss cross-SMC interactions as well as the composition of SMCs into larger structures. Copyright © 2007 John Wiley & Sons, Ltd.
Body sensor networks consisting of low-power on- body wireless sensors attached to mobile users will be used in the future to monitor the health and well being of patients in hospitals or at home. Such systems need to adapt autonomously to changes in context, user activity, device failure, and the availability or loss of services. To this end, we propose a policy- based architecture that uses the concept of a Self-Managed Cell (SMC) to integrate services, managed resources and a policy interpreter by means of an event bus. Policies permit the declarative specification of adaptation strategy for self- configuration and self-management. We present the design and implementation of the SMC and describe its potential use in a scenario for management of heart monitoring. Preliminary performance measurements are also presented and discussed.
With the emergence of mobile and ubiquitous computing environments, there is a requirement to enable collaborative applications between these environments. As many of these applications have been designed to operate in isolation, making them work together is often complicated by the semantic and ontological differences in the meta-data describing the data to be shared. Typical approaches to overcoming ontological differences require the presence of a third party administrator, an approach incompatible with autonomous systems. This paper presents an approach to automatic ontology mapping suitable for deployment in autonomous, interacting systems for a class of collaborative application. The approach facilitates the collaboration of application-level data collections by identifying areas of ontological conflict and using meta-data values associated with those collections to establish commonality. A music sharing application has been developed to facilitate the sharing of music between peers.
Body sensor networks e.g., for health monitoring, consist of several low-power on-body wireless sensors, higher-level devices such as PDAs and possibly actuators such as drug delivery pumps. It is important that such networks can adapt autonomously to changing conditions such as failures, changes in context e.g., user activity, or changes in the clinical condition of patients. Potential reconfiguration actions include changing the monitoring thresholds on sensors, the analysis algorithms or the configuration of the network itself. This paper presents a policy-based approach for autonomous management of body-sensor networks using the concept of a Self-Managed Cell (SMC). Ponder2 is an implementation of this approach that permits the specification and enforcement of policies that facilitate management and adaptation of the response to changing conditions. A Tiny Policy Interpreter has also been developed in order to provide programmable decision-making capability for BSN nodes.
The primary components in a Self Managed Cell (SMC) -- the event bus, the policy management service, and the discovery service -- are required regardless of the scale of the SMC. However, the behaviour of core services may necessarily be altered to suit the environment within which an SMC operates. This paper discusses the design of core services (primarily, the event bus and discovery service) in wide- area SMCs. Delay-tolerant networking between SMCs is also discussed, as is the implementation of core services leading to an emulated network of SMCs. As the basis for a 'healthmap' capable of representing patient data across a geographic region, the discussion on wide-area SMCs leads into cursory discussion of geographical imaging and visualisation systems.
An event system suitable for very simple devices corresponding to a body area network for monitoring patients is presented. Event systems can be used both for self-management of the components as well as indicating alarms relating to patient health state. Traditional event systems emphasise scalability and complex event dissemination for internet based systems, whereas we are considering ubiquitous systems with wireless communication and mobile nodes which may join or leave the system over time intervals of minutes. Issues such as persistent delivery are also important. We describe the design, prototype implementation, and performance characteristics of an event system architecture targeted at this application domain.
Amongst the challenges of ubiquitous computing is the need to provide management support for personal wireless devices and sensors. In this extended abstract we introduce a policy-based architecture that supports management at varying levels based on the concept of a self-managed cell. Cells include policy-driven agents that support context-based and trust-based access control and system adaptation. Cells can also organize themselves through federation and nesting.
Future e-Health systems will consist of low-power, on-body wireless sensors attached to mobile users that interact with a ubiquitous computing environment. This kind of system needs to be able to configure itself with little or no user input; more importantly, it is required to adapt autonomously to changes such as user movement, device failure, the addition or loss of services, and proximity to other such systems. This extended abstract describes the basic architecture of a Self-Managed Cell (SMC) to address these requirements, and discusses various forms of federation between/among SMCs. This structure is motivated by a typical e-Health scenario.
The growing use of animation in Web pages testifies to the increasing ease with which such multimedia components can be created. This trend indicates a commitment to animation that is often unmatched by the skill of the implementers. The present paper details a set of ten commandments for web animation, intending to sensitise budding animators to key aspects that may impair the communicational effectiveness of their animation. These guidelines are drawn from an extensive literature survey coloured by personal experience of using Web animation packages. Our ten principles are further elucidated by a Web-based on-line tutorial.
With the emergence of mobile and ubiquitous computing environments, there is an increasing need for autonomic management support. A Self-Managed Cell (SMC) has been proposed as an architec- ture for such systems. SMCs will undoubtedly benefit from the ability to seamlessly interoperate with other SMCs with minimal human inter- vention. The Semantic Web has been purported to enable such interop- erability. In this paper we will highlight how Semantic Web technologies may be used to support the collaboration of multiple SMCs.