MergeIA: A Service for Dynamic Merging of Interfering Adaptations in Ubiquitous System

International audienceThe composition of adaptations with system’s application does not always yield to the desired behavior. Each adaptation occurs correctly when it is separated but it may interact with other adaptations when they are combined. These interactions can affect the final behavior after adaptation; we call this an interference. This paper presents an on-going work, which aims to build a generic approach for the dynamic resolution of adaptation interferences in ubiquitous applications. We represent application and adaptation details by graphs; then we apply graph transformation rules on these graphs to resolve interferences. This allows us to express our approach independently of any implementation details of applications and adaptations

Context-aware Authorization in Highly Dynamic Environments

Highly dynamic computing environments, like ubiquitous and pervasive computing environments, require frequent adaptation of applications. Context is a key to adapt suiting user needs. On the other hand, standard access control trusts users once they have authenticated, despite the fact that they may reach unauthorized contexts. We analyse how taking into account dynamic information like context in the authorization subsystem can improve security, and how this new access control applies to interaction patterns, like messaging or eventing. We experiment and validate our approach using context as an authorization factor for eventing in Web service for device (like UPnP or DPWS), in smart home security

Context-sensitive authorization for asynchronous communications

Main requirement of recent computing environments, like mobile and then ubiquitous computing, is to adapt applications to context. On the other hand, access control generally trust users once they have authenticated, despite the fact that they may reach unauthorized situations. We analyse how dynamic information can be used to improve security in the authorization process, especially in the case of asynchronous communications, like messaging or eventing. We experiment and validate our approach using context as an authorization factor for eventing in Web service for device (like UPnP or DPWS)

Dynamic knowledge model evolution in SWoT: a way to improve services selection relevancy over time

Semantic web technologies are gaining momentum in the WoT (Web of Things) community for its promising ability to manage the increasing semantic heterogeneity between devices (Semantic Web of Things, SWoT) in ambient environments. However, most of the approaches rely on ad-hoc and static knowledge models (ontologies) designed for specific domains and applications. While it is a solution for handling the semantic heterogeneity issue, it offers no perspective in term of ontology evolution over time. We study in this paper several approaches allowing: (1) to handle the semantic heterogeneity issue; (2) to capitalize the knowledge contributions throughout the life of the system allowing it to potentially better assist people in their environment over time. One of the approaches is validated on two real use-cases

Aspects of Assembly and Cascaded Aspects of Assembly: Logical and Temporal Properties

Highly dynamic computing environments, like ubiquitous and pervasive computing environments, require frequent adaptation of applications. This has to be done in a timely fashion, and the adaptation process must be as fast as possible and mastered. Moreover the adaptation process has to ensure a consistent result when finished whereas adaptations to be implemented cannot be anticipated at design time. In this paper we present our mechanism for self-adaptation based on the aspect oriented programming paradigm called Aspect of Assembly (AAs). Using AAs: (1) the adaptations process is fast and its duration is mastered; (2) adaptations' entities are independent of each other thanks to the weaver logical merging mechanism; and (3) the high variability of the software infrastructure can be managed using a mono or multi-cycle weaving approach.Comment: 14 pages, published in International Journal of Computer Science, Volume 8, issue 4, Jul 2011, ISSN 1694-081

Context-Sensitive Authorization in Interaction Patterns

Main requirement of recent computing environments, like mobile and then ubiquitous computing, is to adapt applications to context. On the other hand, access control generally trust users once they have authenticated, despite the fact that they may reach unauthorized situations. We analyse how dynamic information can be used to improve security in the authorization process, and what are the implications when applied to interaction patterns. We experiment and validate our approach using context as an authorization factor for eventing in Web service for device (like UPnP or DPWS)

Duomenų apdorojimas ir vizualizavimas mobiliuosiuose įrenginiuose

Straipsnyje nagrinėjami duomenų apdorojimo mobiliuosiuose įrenginiuose bei klasikiniai ir neseniai sukurti vizualizavimo metodai, tinkantys vaizduoti duomenis mažame ekrane. Analizuojami mobiliųjų įrenginių apdorojimo ir duomenų pateikimo ribojimai, į kuriuos atsižvelgiama kuriant programas visur esančių skaičiavimų aplinkose. Apžvalginio tyrimo rezultatus planuojama pritaikyti kuriant saityno paslaugos vizualizavimo modelį paslaugų architektūros stiliaus sistemoje.Data Processing and Visualization on Mobile Devices Kristina Lapin, Sigitas Dapkūnas SummaryThe paper surveys the data processing and visualization peculiarities in mobile devices. Developing the visualisation application to a mobile device a researcher has to consider their computational and size limitations. The mobile and traditional visualization methods for small screens are analysed. Researchers start to address the clutter problem showing the stream of data. The outcome of this research is planned to develop a model of visualisation of web service for a system based on the service-oriented architecture.="font-size: 11pt; line-height: 115%; font-family: Calibri, sans-serif;"

WComp, Middleware for Ubiquitous Computing and System Focused Adaptation

International audienceUbiquitous computing relies on computers present everywhere, at any times and in any things. Indeed with recent years advance in mobile communication technologies and the miniaturization of computer hardware, processing units are becoming invisible and a part of the environment. Middlewares for ubiquitous computing have to manage three main features specific to their environment: devices’ mobility, devices’ heterogeneity and environment’s dynamicity. The devices’ mobility, due to motion of users and their associated devices, forbids to assume that entities are known and will always be available. The second concept, entity’s heterogeneity, outlines the diversity between devices’ capabilities and functionalities provided by new smart objects. Finally, the environment high dynamicity illustrates the ubiquitous world entropy with the appearance and disappearance of devices. Devices used to create applications are thus unknown before discovering them. Then, ubiquitous computing must deal with such a dynamic software environment (called software infrastructure afterwards). As a result, future ubiquitous computing architectures must take into account those three constraints to solve ubiquitous computing challenges.Our model of middleware WComp is based on three parts: a software infrastructure, a service composition architecture, and a compositional adaptation mechanism

Constructing runtime models with bigraphs to address ubiquitous computing service composition volatility

In this thesis, we explore the appropriateness of the language abstractions provided by Bigraphs to construct a model at runtime to tackle the problem of volatility in a service composition running on a mobile device. Our contributions to knowledge are as follows: 1) We have shown that Bigraphs (Milner, 2009) are suitable for expressing models at runtime. 2) We have offered Bigraph language abstractions as an appropriate solution to some of the research problems posed by the models at runtime community (Aßmann et al., 2012). 3) We have discussed the general lessons learnt from using Bigraphs for a practical application such as a model at runtime. 4) We have discussed the general lessons learnt from our experiences of designing models at runtime. 5) We have implemented the model at runtime using the BPL Tool (ITU, 2011) and have experimentally studied the response times of our Bigraphical model. We have suggested appropriate enhancements for the tool based on our experiences. We present techniques to parameterize the reaction rules so that the matching algorithm of the BPL Tool returns a single match giving us the ability to dynamically program the model at runtime. We also show how to query the Bigraph structure