A smart phone senses audio, imagery, and/or other stimulus from a user's environment, and acts autonomously to fulfill inferred or anticipated user desires. In one aspect, the detailed technology concerns phone-based cognition of a scene viewed by the phone's camera. The image processing tasks applied to the scene can be selected from among various alternatives by reference to resource costs, resource constraints, other stimulus information (e.g., audio), task substitutability, etc. The phone can apply more or less resources to an image processing task depending on how successfully the task is proceeding, or based on the user's apparent interest in the task. In some arrangements, data may be referred to the cloud for analysis, or for gleaning. Cognition, and identification of appropriate device response(s), can be aided by collateral information, such as context. A great number of other features and arrangements are also detailed.

Intuitive computing methods and systems

Nowadays, numerous journals and conferences have published articles related to context-aware systems, indicating many researchers' interest. Therefore, the goal of this paper is to review the works that were published in journals, suggest a new classification framework of context-aware systems, and explore each feature of classification framework. This paper is based on a literature review of context-aware systems from 2000 to 2007 using a keyword index and article title search. The classification framework is developed based on the architecture of context-aware systems, which consists of the following five layers: concept and research layer, network layer, middleware layer, application layer and user infrastructure layer. The articles are categorized based on the classification framework. This paper allows researchers to extract several lessons learned that are important for the implementation of context-aware systems.

Context-aware systems

In Wireless Sensor Networks (WSNs), localization is one of the most important technologies since it plays a critical role in many applications, e.g., target tracking. If the users cannot obtain the accurate location information, the related applications cannot be accomplished. The main idea in most localization methods is that some deployed nodes (landmarks) with known coordinates (e.g., GPS-equipped nodes) transmit beacons with their coordinates in order to help other nodes localize themselves. In general, the main localization algorithms are classified into two categories: range-based and range-free. In this paper, we reclassify the localization algorithms with a new perspective based on the mobility state of landmarks and unknown nodes, and present a detailed analysis of the representative localization algorithms. Moreover, we compare the existing localization algorithms and analyze the future research directions for the localization algorithms in WSNs.

Localization algorithms of Wireless Sensor Networks: a survey

We describe a distributed simulation tool which addresses the unique needs for the simulation of emergency response scenarios. The simulation tool adopts the multi-agent paradigm, so as to facilitate the modelling of diverse and autonomous agents, and it provides mechanisms for the interaction of the entities that are being simulated. It operates in a distributed fashion to reduce the simulation time required for such large-scale systems. The simulation tool represents the individuals that need to be evacuated, the resources that contribute to the evacuation including human rescuers, and other active resources and entities which may include robots and which can autonomously interact with the environment and with each other and take individual or collaborative decisions. We illustrate the tool with an application and compare the results for both centralized and distributed execution. Our results also show the significant reduction in execution time that is achieved for different degrees of distribution of the simulator on multiple servers.

Distributed Building Evacuation Simulator for Smart Emergency Management

Pervasive computing and Internet of Things (IoTs) paradigms have created a huge potential for new business. To fully realize this potential, there is a need for a common way to abstract the heterogeneity of devices so that their functionality can be represented as a virtual computing platform. To this end, we present novel semantic level interoperability architecture for pervasive computing and IoTs. There are two main principles in the proposed architecture. First, information and capabilities of devices are represented with semantic web knowledge representation technologies and interaction with devices and the physical world is achieved by accessing and modifying their virtual representations. Second, global IoT is divided into numerous local smart spaces managed by a semantic information broker (SIB) that provides a means to monitor and update the virtual representation of the physical world. An integral part of the architecture is a resolution infrastructure that provides a means to resolve the network address of a SIB either using a physical object identifier as a pointer to information or by searching SIBs matching a specification represented with SPARQL. We present several reference implementations and applications that we have developed to evaluate the architecture in practice. The evaluation also includes performance studies that, together with the applications, demonstrate the suitability of the architecture to real-life IoT scenarios. In addition, to validate that the proposed architecture conforms to the common IoT-A architecture reference model (ARM), we map the central components of the architecture to the IoT-ARM.

Semantic Interoperability Architecture for Pervasive Computing and Internet of Things

Agent based middleware infrastructure for autonomous context-aware ubiquitous computing services

We present an architectural framework along with a set of middleware elements, facilitating the integration of perceptual components, sensors, actuators, and context-modeling scripts, comprising sophisticated ubiquitous computing applications in smart spaces. The architecture puts special emphasis on the integration of perceptual components contributed by a variety of technology providers, which has not been adequately addressed in legacy architectures. Moreover, the introduced architecture allows for intelligent discovery and management of resources. Along with the description of this breadboard architecture, we present its non-functional features and assess its performance. We also outline a rich set of practical prototype pervasive services that have been built, based on this architecture. These services emphasize on providing non-obtrusive human-centric assistance (e.g., memory aids, meeting recordings, pertinent information) in the scope of meetings, lectures and presentation, Experiences from building these services manifest the benefits of the introduced architecture.

A breadboard architecture for pervasive context-aware services in smart spaces: middleware components and prototype applications

Recently, several standards have emerged for ontology markup languages that can be used to formalize all kinds of knowledge. However, there are no widely accepted standards yet that define APIs to manage ontological data. Processing ontological information still suffers from the heterogeneity imposed by the plethora of available ontology management systems. Moreover, ubiquitous computing environments usually comprise software components written in a variety of different programming languages, which makes it particularly difficult to establish a common ontology management API with programming language agnostic semantics. We implemented an ontological Knowledge Base Server, which can expose the functionality of arbitrary off-the-shelf ontology management systems via a formally specified and well defined API. A case study was carried out in order to demonstrate the feasibility of our approach to use a formally specified ontology management API to implement a registry for ubiquitous computing systems.

/pdf/a-formally-specified-ontology-management-api-as-a-registry-1w14edeexl.pdf

A formally specified ontology management API as a registry for ubiquitous computing systems

Europeana has put in a stretch many known procedures in digital libraries, imposing requirements difficult to be implemented in many small institutions, often without dedicated systems support personnel. Although there are freely available open source software platforms that provide most of the commonly needed functionality such as OAI-PMH support, the migration from legacy software may not be easy, possible or desired. Furthermore, advanced requirements like selective harvesting according to complex criteria are not widely supported. To accommodate these needs and help institutions contribute their content to Europeana, we developed a series of tools. For the majority of small content providers that are running DSpace, we developed a DSpace plugin, to convert and augment the Dublin Core metadata according to Europeana ESE requirements. For sites with different software, incompatible with OAIPMH, we developed wrappers enabling repeatable generation and harvesting of ESE-compatible metadata via OAI-PMH. In both cases, the system is able to select and harvest only the desired metadata records, according to a variety of configuration criteria of arbitrary complexity. We applied our tools to providers with sophisticated needs, and present the benefits they achieved.

http://helios-eie.ekt.gr/EIE/bitstream/10442/8753/2/tpdl2011_110_camera_ready_post-print.pdf

Implementing enhanced OAI-PMH requirements for Europeana

Context-aware ubiquitous computing environments tend to be highly distributed and heterogeneous, while also featuring increased dynamism as elements, devices and middleware components join, leave and change their status. In such environments, information is derived and fused with numerous sensors and context-aware middleware components. As a result, directory and naming services, along with reasoning mechanisms, are at the heart of any non-trivial ubiquitous computing application. In this paper, we argue that semantic web technologies can deal with directory service requirements of ubiquitous computing environments, much more efficiently than the wide range of legacy mechanisms. To justify this claim, we introduce a model that could greatly facilitate the development, deployment and management of ubiquitous computing applications. This model relies on semantic web technologies (i.e., ontology management) and facilitates the integration of hardware and middleware elements in the scope of a ubiquitous computing application. Using this model and its underlying ontology management schemes, we implemented proof-of-concept applications in the scope of a smart space comprising numerous sensors, actuators and middleware components. Based on the implementation experience, we outline the merits of using semantic web technologies in ubiquitous context-aware computing and smart spaces.

Kostas Stamatis

Papers

Agent based middleware infrastructure for autonomous context-aware ubiquitous computing services

A breadboard architecture for pervasive context-aware services in smart spaces: middleware components and prototype applications

A formally specified ontology management API as a registry for ubiquitous computing systems

Implementing enhanced OAI-PMH requirements for Europeana

Semantic web technologies for ubiquitous computing resource management in smart spaces