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Showing papers on "Context awareness published in 2007"


Journal ArticleDOI
01 Jun 2007
TL;DR: Common architecture principles of context-aware systems are presented and a layered conceptual design framework is derived to explain the different elements common to mostcontext-aware architectures.
Abstract: Context-aware systems offer entirely new opportunities for application developers and for end users by gathering context data and adapting systems behaviour accordingly. Especially in combination with mobile devices, these mechanisms are of high value and are used to increase usability tremendously. In this paper, we present common architecture principles of context-aware systems and derive a layered conceptual design framework to explain the different elements common to most context-aware architectures. Based on these design principles, we introduce various existing context-aware systems focusing on context-aware middleware and frameworks, which ease the development of context-aware applications. We discuss various approaches and analyse important aspects in context-aware computing on the basis of the presented systems.

2,036 citations


Journal ArticleDOI
TL;DR: A greater understanding of which aspects of context are important in a health care setting is required; the inherent sociotechnical nature of context-aware applications in health care; and the need to draw on a number of disciplines to conduct this research are concluded.

275 citations


Journal ArticleDOI
TL;DR: This article illustrates a conceptual framework that provides modeling facilities for context-aware, multichannel Web applications and shows how high-level modeling constructs can drive the application development process through automatic code generation.
Abstract: Context-aware, multi-channel Web applications are more and more gaining consensus among both content providers and consumers, but very few proposals exist for their conceptual modeling. This article illustrates a conceptual framework that provides modeling facilities for context-aware, multichannel Web applications; it also shows how high-level modeling constructs can drive the application development process through automatic code generation. Our work stresses the importance of user-independent, context-triggered adaptation actions, in which the context plays the role of a “first class” actor, operating independently of users on the same hypertext the users navigate. Modeling concepts are based on WebML (Web Modeling Language), an already established conceptual model for data-intensive Web applications, which is also accompanied by a development method and a CASE tool. However, given their general validity, the concepts of this article shape up a complete framework that can be adopted independently of the chosen model, method, and tool.

184 citations


Book
01 Jan 2007
TL;DR: These proceedings contain the papers presented at the 2nd International Workshop on Location- and Context-Awareness in May of 2006, intended to present research aimed at sensing, inferring, and using location and context data in ways that help the user.
Abstract: Bootstrapping a Location Service Through Geocoded Postal Addresses.- Deployment, Calibration, and Measurement Factors for Position Errors in 802.11-Based Indoor Positioning Systems.- LifeTag: WiFi-Based Continuous Location Logging for Life Pattern Analysis.- Scalable Recognition of Daily Activities with Wearable Sensors.- Information Overlay for Camera Phones in Indoor Environments.- SocialMotion: Measuring the Hidden Social Life of a Building.- A Unified Semantics Space Model.- Federation and Sharing in the Context Marketplace.- A Taxonomy for Radio Location Fingerprinting.- Inferring the Everyday Task Capabilities of Locations.- The Whereabouts Diary.- Adaptive Learning of Semantic Locations and Routes.- Signal Dragging: Effects of Terminal Movement on War-Driving in CDMA/WCDMA Networks.- Modeling and Optimizing Positional Accuracy Based on Hyperbolic Geometry for the Adaptive Radio Interferometric Positioning System.- Inferring Position Knowledge from Location Predicates.- Preserving Anonymity in Indoor Location System by Context Sensing and Camera-Based Tracking.- Localizing Tags Using Mobile Infrastructure.

171 citations


Proceedings ArticleDOI
19 Mar 2007
TL;DR: This paper proposes an ontology-based generic context management (GCoM) model that facilitates context reasoning by providing structure for contexts, rules and their semantics.
Abstract: The behavior of pervasive applications should depend not only on their internal state and user interactions but also on the context sensed during their execution. In this paper, we propose an ontology-based generic context management (GCoM) model. The GCoM model facilitates context reasoning by providing structure for contexts, rules and their semantics. Context and context semantics in GCoM model are represented using the upper and the lower level ontology. Rules are represented using ontology compatible rule languages. Even though ontology data has static nature, GCoM model is designed to be dynamic and reusable in multiple domains of pervasive applications where resource limitation is a key issue. Initial prototype of the use of the model is created and the result obtained is promising

122 citations


13 Feb 2007
TL;DR: This paper provides a survey of a chosen set of context-aware middleware systems, and categorises their properties and use according to a taxonomy.
Abstract: This paper provides a survey of a chosen set of context-aware middleware systems, and categorises their properties and use according to a taxonomy. An overview of each system is provided, as well as descriptions of the different properties.

120 citations


Journal ArticleDOI
TL;DR: In this article, the authors discuss the relevance of context consciousness and sensitivity in relation to one of the main aims given to SEA implementation, i.e. to contribute to the integration of environmental perspectives in planning processes.

119 citations


Book ChapterDOI
25 Nov 2007
TL;DR: In evaluating the performance of C2_Music using a real world data, it outperforms the comparative system that utilizes the user's demographics and behavioral patterns only.
Abstract: The recommendation system is one of the core technologies for implementing personalization services Recommendation systems in ubiquitous computing environment should have the capability of context-awareness In this research, we developed a music recommendation system, which we shall call C2_Music, which utilizes not only the user's demographics and behavioral patterns but also the user's context For a specific user in a specific context, the C2_Music recommends the music that the similar users listened most in the similar context In evaluating the performance of C2_Music using a real world data, it outperforms the comparative system that utilizes the user's demographics and behavioral patterns only

110 citations


Journal ArticleDOI
TL;DR: This paper gives initial requirements for such a framework and it gives a first attempt for a functional decomposition and the use of the framework is illustrated by means of an epilepsy tele-monitoring scenario.
Abstract: Several social-economical developments, like the ageing society, stimulate the use of ICT applications for mobile healthcare (e.g., tele-monitoring). To support novel m-health applications, the consequences of developing these applications should be considered in the scope of a comprehensive architecture. Additionally, contextual information plays an important role for personalised healthcare and should be considered in such architectures. This paper describes ongoing research that focuses on developing an application framework for supporting the development of context-aware m-health applications. It gives initial requirements for such a framework and it gives a first attempt for a functional decomposition. The use of the framework is illustrated by means of an epilepsy tele-monitoring scenario.

105 citations


Book ChapterDOI
07 Nov 2007
TL;DR: The paper motivates the need for novel IT-based approaches to the conditioning of commercial products and product assemblies, introduces important relevant challenges and research domains, and provides an early definition of Smart Products.
Abstract: Sophisticated commercial products and product assemblies can greatly benefit from novel IT-based approaches to the conditioning of these products and of ‘product knowledge’, leading to what we call Smart Products. The paper motivates the need for such novel approaches, introduces important relevant challenges and research domains, and provides an early definition of Smart Products.

103 citations


Journal ArticleDOI
TL;DR: This article introduces context aware systems in mobile computing environments, review the basic mechanisms underlying the operation of such systems, and discusses notable work and important architectures in the area.
Abstract: In this article, we report software architectures for context awareness in mobile computing environments, sensor centric systems and discuss context modeling issues. Defining an architecture for supporting context-aware applications for mobile devices explicitly implies a scalable description of how to represent contextual information and which are the abstraction models capable of handling such information. Using sensors to retrieve contextual information (e.g., user location) leads to a sensor network scheme that provides services to the applications level. Operations for capturing, collating, storing, and disseminating contextual information at the lowest level and aggregating it into increasingly more abstract models qualify the context-aware systems. In this article, we introduce context aware systems in mobile computing environments, review the basic mechanisms underlying the operation of such systems, and discuss notable work and important architectures in the area.

Journal ArticleDOI
TL;DR: A predictive framework for location-aware resource optimization in smart homes based on the hypothesis that the mobility of an inhabitant creates an uncertainty of his location is developed to minimize the maintenance and operations cost of the smart home, as well as to provide better comfort to the inhabitants.
Abstract: Rapid advances in a wide range of wireless access and networking technologies, along with ubiquitous computing and communications, have set the stage for the development of smart environments (for example, smart homes or offices). "Context awareness" is perhaps the most salient feature in such intelligent (indoor) environments. Examples of contexts include the "location" and "activities" of the inhabitants among others. In this paper, we develop a predictive framework for location-aware resource optimization in smart homes based on the hypothesis that the mobility of an inhabitant creates an uncertainty of his location. With the help of information theory, the proposed framework is shown to minimize this uncertainty through optimal learning and prediction of the inhabitant's movement (location) profiles captured in the symbolic domain. The concept of the asymptotic equipartition property (AEP) is also used to predict the inhabitant's most likely routes (or path-segments) with a high degree of accuracy. Successful predictions help in several ways, such as automated device control and proactive reservation of resources (for example, electrical energy and other utilities or scarce wireless bandwidth for mobile multimedia applications) along the inhabitant's most probable locations and routes. The goal here is to minimize the maintenance and operations cost of the smart home, as well as to provide better comfort to the inhabitants. Experimental results from a typical smart home floor plan corroborate the prediction success and significant reduction in daily energy consumption and manual operations of devices.

Journal ArticleDOI
TL;DR: A multi-agent framework that considers different contexts to support personalized services on wireless networks and preliminary results show that the proposed approach to personalization is promising and efficient in the deployment of mobile services.
Abstract: The mobile Internet allows users to obtain digitized contents and services from wired and wireless networks virtually anywhere at any time via different handheld mobile devices. However, due to the distinct features of mobile users, mobile devices and wireless networks, deploying mobile services is not as straightforward as generally expected. To ensure the success of mobile services, this paper presents a multi-agent framework that considers different contexts to support personalized services on wireless networks. In the proposed approach, client users, content providers, and service providers are all considered as software agents. They interoperate on the same platform to request and deliver mobile services. The most important issues related to agent operations and context awareness in an agent world are also discussed and analyzed. To verify our framework, different application services are developed accordingly on a publicly available middleware platform. Experiments are conducted for both services to evaluate their corresponding performance. The preliminary results show that our multi-agent approach to personalization is promising and efficient in the deployment of mobile services.

Journal ArticleDOI
TL;DR: This work proposes the use of Fuzzy Logic theory with the purpose of determining and reasoning about the current situation of the involved user and elaborate on the architectural model that enables the system to assume actions autonomously according to previous user reactions and current situation.

Proceedings ArticleDOI
19 Mar 2007
TL;DR: This paper proposes a simple model for the representation of contextual information, the design and implementation of a general infrastructure for browsing the world, as well as some exemplar services it has implemented over it.
Abstract: The imminent mass deployment of pervasive computing technologies such as sensor networks and RFID tags, together with the increasing participation of the Web community in feeding geo-located information within tools such as Google Earth, will soon make available an incredible amount of information about the physical and social worlds and their processes. This opens up the possibility of exploiting all such information for the provisioning of pervasive context-aware services for "browsing the world", i.e., for facilitating users in gathering information about the world, interacting with it, and understanding it. However, for this to occur, proper models and infrastructures must be developed. In this paper we propose a simple model for the representation of contextual information, the design and implementation of a general infrastructure for browsing the world, as well as some exemplar services we have implemented over it

Proceedings ArticleDOI
Jong-Hwan Kim1, Kang-Hee Lee2, Yong-Duk Kim1, Naveen Kuppuswamy1, Jun Jo3 
10 Apr 2007
TL;DR: The components and overall architecture of the ubiquitous robot (Ubibot) system developed to demonstrate ubiquitous robotics, a new paradigm for integrated services, are presented and the proof of concept of this powerful new paradigm which shows great promise is demonstrated.
Abstract: This paper presents the components and overall architecture of the ubiquitous robot (Ubibot) system developed to demonstrate ubiquitous robotics, a new paradigm for integrated services. The system has been developed on the basis of the definition of the ubiquitous robot as that of encompassing the software robot Sobot, embedded robot Embot and the mobile robot Mobot. This tripartite partition, which independently manifests intelligence, perception and action, enables the abstraction of intelligence through the standardization of sensory data and motor or action commands. The Ubibot system itself is introduced along with its component subsystems of Embots, the position Embot, vision Embot and sound Embot, the Mobots of Mybot and HSR, the Sobot, Rity, a virtual pet modeled as an artificial creature, and finally the middleware which seamlessly enables interconnection between other components. Three kinds of experiments are devised to demonstrate the fundamental features, of calm sensing, context awareness and seamless service transcending the spatial limitations in the abilities of earlier generation personal robots. The experiments demonstrate the proof of concept of this powerful new paradigm which shows great promise.

Journal ArticleDOI
TL;DR: This paper presents the design and implementation of a middleware infrastructure for ubiquitous computing services, which facilitates development of ubiquitous services, allowing the service developer to focus on the service logic rather than the middleware implementation.

Proceedings ArticleDOI
25 May 2007
TL;DR: A context inference scheme that realizes a user posture inference with only one acceleration sensor embedded in a mobile handset and can infer a user's posture with more than 96%.
Abstract: User context recognition is one of the important technologies for realizing context aware services. Conventional multi sensor based approach has advantages in that it can generate variety of contexts with less computation resources by using many different sensors. However, such systems tend to be complex and cumbersome and, thus, do not fit in well with mobile environment. In this sense, a single sensor based approach is suitable for mobile environments. In this paper, we show a context inference scheme that realizes a user posture inference with only one acceleration sensor embedded in a mobile handset. Our system automatically detects the sensor position on the user's body and selects the most relevant inference method dynamically. Our experimental results show that the system can infer a user's posture (sitting, standing, walking, and running) with an accuracy of more than 96%.

Journal ArticleDOI
TL;DR: A novel middleware solution, called Mobile agent-based Ubiquitous multimedia Middleware (MUM), that performs effective and context-aware handoff management to transparently avoid service interruptions during both horizontal and vertical handoffs is proposed.

Proceedings ArticleDOI
24 Jul 2007
TL;DR: This paper presents a model-based requirements engineering approach to systematically analyze and specify the basic system behavior as well as the adaptation behavior starting from customer and business needs.
Abstract: Building realistic end user scenarios for ubiquitous computing applications entails large up-front investments. Many context adaptive applications so far fail to live up to their expectations. Firstly, this is due to poorly conceived development tools and methods compared to other, more mature domains. And secondly, they seem to be particularly prone to problems related to a discrepancy between user expectation and systems behavior. This unwanted behavior prevents the vision of an emerging trend of context aware and adaptive applications in ubiquitous computing to become reality. A good understanding of business and customer's requirements may be of immense importance. This paper presents a model-based requirements engineering approach to systematically analyze and specify the basic system behavior as well as the adaptation behavior starting from customer and business needs.

Patent
30 Jun 2007
TL;DR: In this paper, a method for accepting and enforcing user selectable privacy settings for context awareness including location awareness data on a computing platform is described, where the method may identify a requestor, assign a privacy setting to the requester and detect a request for location information from the requestor.
Abstract: In one embodiment a method is disclosed for accepting and enforcing user selectable privacy settings for context awareness including location awareness data on a computing platform. The method may identify a requestor, assign a privacy setting to the requester then detect a request for location information from the requestor. The method may transmit location information to the requester based on the user selected privacy setting. The user selected privacy setting may have a granularity assigned to each requestor based on a privacy preference and the method may entirely block the location information from being disclosed or the method may modify the granularity/accuracy of the location information based on the privacy setting to report context of an appropriate level of granularity according to the privacy setting configured by the user. Other embodiments are also disclosed.

Proceedings ArticleDOI
01 Jul 2007
TL;DR: A context-aware semantic service discovery architecture designed to perform distributed service discovery in heterogeneous networks is proposed, which is technology independent and compatible with most of the existent service discovery protocols.
Abstract: In the last few years telecommunications and Internet have spread all over the world, in a pervasive way, connecting millions of devices, people, sensors and services without a planned strategy. In such scenario the discovery of services represent still an open challenging research field. To address that problem this paper proposes a context-aware semantic service discovery architecture designed to perform distributed service discovery in heterogeneous networks. This novel architecture is technology independent and compatible with most of the existent service discovery protocols; it inherits and extends the results of the last research groups in the field of context-aware service discovery based on the use of semantic languages. The present work presents the first results of the service discovery design activity which has been carried out within DAIDALOS II (Designing Advanced network Interfaces for the Delivery and Administration of Location independent, Optimised personal Services), a project granted in the European 6th Framework Research Programme, within the IST (Information Society and Technology) thematic area.

Journal ArticleDOI
01 Oct 2007
TL;DR: The results indicate that the usefulness of a ubiquitous computing environment supporting work activities in healthcare can benefit from context-aware mobile information access, but interaction design for such systems must be carefully thought out and thoroughly evaluated.
Abstract: Ubiquitous technologies have potentials to play major roles in different real world organizational settings. One of the areas where applying ubiquitous technologies has been given a lot of attention is in the healthcare domain. Here, users are frequently on the move while at the same time relying increasingly on centralized computerized information. In this paper, we explore ubiquitous technologies in the real world through two studies in the healthcare domain. First, we look at the use and usability of a ubiquitous electronic patient record (EPR) system distributed on desktop and laptop computers throughout a large hospital. Secondly, we present an extension to this ubiquitous computing environment in the form of a context-aware mobile computer terminal prototype. The usability of the mobile EPR prototype was evaluated in both laboratory and field settings. Our results indicate that the usefulness of a ubiquitous computing environment supporting work activities in healthcare can benefit from context-aware mobile information access. However, interaction design for such systems must be carefully thought out and thoroughly evaluated. Also, while the use of mobile and stationary computers complement each other very well, we found that the usefulness of ubiquitous computing environments in healthcare may benefit from additional elements such as situated displays at key locations and on key objects, and from seamless integration between the different devices comprising the system as a whole.

Proceedings Article
01 Jan 2007
TL;DR: Wang et al. as discussed by the authors proposed a semantic and adaptive middleware platform, ScudWare, for smart vehicle space, which consists of three key components, namely 1) semantic virtual agents; 2) a semantic context management service; and 3) an adaptive component management service.
Abstract: Compared with smart spaces addressed previously, the smart vehicle space is quite special. First, unlike room, it is a high mobile space. Second, it requires frequent information exchange with the outer environment; for instance, it may need local traffic information and other local services. The complex vehicle space needs a software infrastructure of high adaptation to meet the complex and easy variational situations. This paper proposes a semantic and adaptive middleware platform, i.e., ScudWare, for smart vehicle space. In ScudWare, techniques of multiagent, context-aware, and adaptive component management are smoothly synthesized. It consists of three key components, namely 1) semantic virtual agents; 2) a semantic context management service; and 3) an adaptive component management service. This enables entities in smart vehicle space to interact autonomously, provides semantic-integration context awareness, and supports component-based adaptability and scalability. A test bed of smart car space is built to evaluate the ScudWare, which demonstrates the effectiveness and efficiency of ScudWare.

Journal ArticleDOI
TL;DR: This paper proposes a semantic and adaptive middleware platform, i.e., ScudWare, for smart vehicle space, which enables entities insmart vehicle space to interact autonomously, provides semantic-integration context awareness, and supports component-based adaptability and scalability.
Abstract: Compared with smart spaces addressed previously, the smart vehicle space is quite special. First, unlike room, it is a high mobile space. Second, it requires frequent information exchange with the outer environment; for instance, it may need local traffic information and other local services. The complex vehicle space needs a software infrastructure of high adaptation to meet the complex and easy variational situations. This paper proposes a semantic and adaptive middleware platform, i.e., ScudWare, for smart vehicle space. In ScudWare, techniques of multiagent, context-aware, and adaptive component management are smoothly synthesized. It consists of three key components, namely 1) semantic virtual agents; 2) a semantic context management service; and 3) an adaptive component management service. This enables entities in smart vehicle space to interact autonomously, provides semantic-integration context awareness, and supports component-based adaptability and scalability. A test bed of smart car space is built to evaluate the ScudWare, which demonstrates the effectiveness and efficiency of ScudWare

Journal ArticleDOI
TL;DR: A three-dimensional CA model for peer recommendation that includes CA to knowledge potential, social proximity and technical access is proposed, which is promising as an aid to the peer seeker in finding suitable knowledge collaborators.
Abstract: For learners in distributed e-learning environments, it is difficult, but very important, to locate the right peer for collaboration on the right knowledge, at the right time and in the right way. This paper proposes the use of context awareness (CA) to support peer recommendation in the e-learning context. For this purpose, this paper explores the e-learning context that involves knowledge, social and technical contexts. Accordingly, this paper proposes a three-dimensional CA model for peer recommendation that includes CA to knowledge potential, social proximity and technical access. By matching the peer seeker and the peer candidate with respect to these three dimensions, the CA information is promising as an aid to the peer seeker in finding suitable knowledge collaborators. The importance of activity context is highlighted in CA-supported peer-recommendation mechanism. A five-dimensional (who, what, how, when and where) representation approach is suggested for activity-context description.

Journal ArticleDOI
TL;DR: The design methodology in its conceptual, logical and logistic phases determine the VSDB ambient which is the set of personal and environmental characteristics determining the portion of data that must be stored on the portable device.

Journal ArticleDOI
TL;DR: This paper proposes an approach based on Bayesian networks for building recommender systems that minimize context acquisition and shows that a two-tiered context model can effectively capture the causal dependencies among context parameters, enabling a recommender system to compensate for missing and erroneous context inputs.
Abstract: Acquisition of context poses unique challenges to mobile context-aware recommender systems. The limited resources in these systems make minimizing their context acquisition a practical need, and the uncertainty in the mobile environment makes missing and erroneous context inputs a major concern. In this paper, we propose an approach based on Bayesian networks (BNs) for building recommender systems that minimize context acquisition. Our learning approach iteratively trims the BN-based context model until it contains only the minimal set of context parameters that are important to a user. In addition, we show that a two-tiered context model can effectively capture the causal dependencies among context parameters, enabling a recommender system to compensate for missing and erroneous context inputs. We have validated our proposed techniques on a restaurant recommendation data set and a Web page recommendation data set. In both benchmark problems, the minimal sets of context can be reliably discovered for the specific users. Furthermore, the learned Bayesian network consistently outperforms the J4.8 decision tree in overcoming both missing and erroneous context inputs to generate significantly more accurate predictions.

Proceedings ArticleDOI
13 Jun 2007
TL;DR: The paper shows how ontologies and logic programming rules can be used to leverage policy adaptation and describes Proteus that, as a key feature, combines these two design guidelines to enable dynamic adaptation of policies depending on context changes.
Abstract: The growing diffusion of portable devices enables users to benefit from anytime and anywhere impromptu collaboration. Appropriate policy models that take into account the dynamicity and heterogeneity of the new pervasive collaboration scenario are crucial to ensure secure sharing of information. Collaborating entities cannot be predetermined and resource availability frequently varies, even unpredictably, due to user/device mobility, thus complicating resource access control. Policies cannot be defined based on entity's identities/roles, as in traditional security solutions, or be specified a priori to face any operative run-time condition, and require continuous adjustments to adapt to the current situation. To address these issues this paper advocates the adoption of a semantic context-aware paradigm to policy specification. Context- awareness allows operations on resources to be controlled based on context visibility whereas semantic technologies allow the high-level description and reasoning about context/policies. The paper describes Proteus that, as a key feature, combines these two design guidelines to enable dynamic adaptation of policies depending on context changes. In particular, the paper shows how ontologies and logic programming rules can be used to leverage policy adaptation.

Proceedings ArticleDOI
19 Mar 2007
TL;DR: The role of existing "probabilistic" schemes to reason about various everyday situations on the basis of data from multiple heterogeneous physical sensors are investigated, including fuzzy logic, hidden Markov models, Bayesian networks, and Dempster-Schafer theory of evidence.
Abstract: This paper investigates the role of existing "probabilistic" schemes to reason about various everyday situations on the basis of data from multiple heterogeneous physical sensors. The schemes we discuss are fuzzy logic, hidden Markov models, Bayesian networks, and Dempster-Schafer theory of evidence. The paper also presents a conceptual architecture and identifies the suitable scheme to be employed by each component of the architecture. As a proof-of-concept, we will introduce the architecture we implemented to model various places on the basis of data from temperature, light intensity and relative humidity sensors