Controlling services in a mobile context-aware infrastructure

Context-aware application behaviors can be described as logic rules following the Event-Control-Action (ECA) pattern. In this pattern, an Event models an occurrence of interest (e.g., a change in context); Control specifies a condition that must hold prior to the execution of the action; and an Action represents the invocation of arbitrary services. We have defined a Controlling service aiming at facilitating the dynamic configuration of ECA rule specifications by means of a mobile rule engine and a mechanism that distributes context reasoning activities to a network of context processing nodes. In this paper we present a novel context modeling approach that provides application developers and users with more appropriate means to define context information and ECA rules. Our approach makes use of ontologies to model context information and has been developed on top of web services technology

Persistent Contextual Values as Inter-Process Layers

Mobile applications today often fail to be context aware when they also need to be customizable and efficient at run-time. Context-oriented programming allows programmers to develop applications that are more context aware. Its central construct, the so-called layer, however, is not customizable. We propose to use novel persistent contextual values for mobile development. Persistent contextual values automatically adapt their value to the context. Furthermore they provide access without overhead. Key-value configuration files contain the specification of contextual values and the persisted contextual values themselves. By modifying the configuration files, the contextual values can easily be customized for every context. From the specification, we generate code to simplify development. Our implementation, called Elektra, permits development in several languages including C++ and Java. In a benchmark we compare layer activations between threads and between applications. In a case study involving a web-server on a mobile embedded device the performance overhead is minimal, even with many context switches.Comment: 8 pages Mobile! 16, October 31, 2016, Amsterdam, Netherland

A novel context ontology to facilitate interoperation of semantic services in environments with wearable devices

The LifeWear-Mobilized Lifestyle with Wearables (Lifewear) project attempts to create Ambient Intelligence (AmI) ecosystems by composing personalized services based on the user information, environmental conditions and reasoning outputs. Two of the most important benefits over traditional environments are 1) take advantage of wearable devices to get user information in a nonintrusive way and 2) integrate this information with other intelligent services and environmental sensors. This paper proposes a new ontology composed by the integration of users and services information, for semantically representing this information. Using an Enterprise Service Bus, this ontology is integrated in a semantic middleware to provide context-aware personalized and semantically annotated services, with discovery, composition and orchestration tasks. We show how these services support a real scenario proposed in the Lifewear project

Police Interventions as a Context-aware System. A Case of a Contextual Data Modelling

Smart systems which operate in Intelligent Environments (IE) are complex. They analyse the large volumes of various contextual data on-line and often in real time to obtain, autonomously and reliably, the required pro-activeness of a system which operates pervasively. We proposed both a development framework for context-aware systems and a context-based decision making scheme for the system of managing police interventions, focusing on providing support for police patrols in life threatening situations. This system, owing to the symultaneous collection of rich contextual information from many police officers, which constitute the mobile network, as well as the complex processes of contextual reasoning, takes automatic decisions on supporting officers in emergency. We implemented the initial, yet not trivial, simulations of the system behaviour within the whole city. The results obtained prove the feasibility of the framework

C-Arc: A Novel Architecture for Next Generation Context- Aware Systems

Computing is becoming increasingly mobile and ubiquitous. This implies that applications and services must be aware and adapt to highly dynamic environments. However, building contextaware mobile services is currently a complex and time consuming task. The emergence of truly ubiquitous computing, enabled by the availability of mobile and heterogeneous devices and an increasing number of commercial off-the-shelf sensing technologies, is hampered by the lack of standard architectural support for the development of context-aware systems. In this paper, the common architecture principles of context-aware systems are presented and the crucial contextaware architecture issues to support the next generation context-aware systems which will enable seamless service provisioning in heterogeneous, dynamically varying computing and communication environments are identified and discussed. Furthermore, a novel architecture, CArc,is proposed to aid in the development of the next generation context-aware systems. A prototype implemented of C-Arc is also presented to demonstrate the architecture. C-Arc provides support for most of the tasks involved in dealing with context, namely acquiring context from various sources, interpreting context and disseminating context.Keywords: Context-aware architecture, context-aware systems, context-aware mobile services,mobile and ubiquitous computing