186 research outputs found
Ontology-Based Context-Aware Service Discovery for Pervasive Environments
Existing service discovery protocols use a service matching process in order to offer services of interest to the clients. Potentially, the context information of the services and client can be used to improve the quality of service matching. To make use of context information in service matching, service discovery needs to address certain challenges. Firstly, it is required that the context information should have unambiguous representation. Secondly, the mobile devices should be able to disseminate context information seamlessly in the fixed network. And thirdly, dynamic nature of the context information should be taken into account. The proposed Context Aware Service Discovery (CASD) architecture deals with these challenges by means of an ontological representation and processing of context information, a concept of nomadic mobile context source and a mechanism of persistent service discovery respectively. This paper discusses proposed CASD architecture, its implementation and suggests further enhancements
A Mobile Computing Architecture for Numerical Simulation
The domain of numerical simulation is a place where the parallelization of
numerical code is common. The definition of a numerical context means the
configuration of resources such as memory, processor load and communication
graph, with an evolving feature: the resources availability. A feature is often
missing: the adaptability. It is not predictable and the adaptable aspect is
essential. Without calling into question these implementations of these codes,
we create an adaptive use of these implementations. Because the execution has
to be driven by the availability of main resources, the components of a numeric
computation have to react when their context changes. This paper offers a new
architecture, a mobile computing architecture, based on mobile agents and
JavaSpace. At the end of this paper, we apply our architecture to several case
studies and obtain our first results
Forum Session at the First International Conference on Service Oriented Computing (ICSOC03)
The First International Conference on Service Oriented Computing (ICSOC) was held in Trento, December 15-18, 2003. The focus of the conference ---Service Oriented Computing (SOC)--- is the new emerging paradigm for distributed computing and e-business processing that has evolved from object-oriented and component computing to enable building agile networks of collaborating business applications distributed within and across organizational boundaries. Of the 181 papers submitted to the ICSOC conference, 10 were selected for the forum session which took place on December the 16th, 2003. The papers were chosen based on their technical quality, originality, relevance to SOC and for their nature of being best suited for a poster presentation or a demonstration. This technical report contains the 10 papers presented during the forum session at the ICSOC conference. In particular, the last two papers in the report ere submitted as industrial papers
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
Mobihealth: mobile health services based on body area networks
In this chapter we describe the concept of MobiHealth and the approach developed during the MobiHealth project (MobiHealth, 2002). The concept was to bring together the technologies of Body Area Networks (BANs), wireless broadband communications and wearable medical devices to provide mobile healthcare services for patients and health professionals. These technologies enable remote patient care services such as management of chronic conditions and detection of health emergencies. Because the patient is free to move anywhere whilst wearing the MobiHealth BAN, patient mobility is maximised. The vision is that patients can enjoy enhanced freedom and quality of life through avoidance or reduction of hospital stays. For the health services it means that pressure on overstretched hospital services can be alleviated
UBIDEV: a homogeneous service framework for pervasive computing environments
This dissertation studies the heterogeneity problem of pervasive computing system from the viewpoint of an infrastructure aiming to provide a service-oriented application model. From Distributed System passing through mobile computing, pervasive computing is presented as a step forward in ubiquitous availability of services and proliferation of interacting autonomous entities. To better understand the problems related to the heterogeneous and dynamic nature of pervasive computing environments, we need to analyze the structure of a pervasive computing system from its physical and service dimension. The physical dimension describes the physical environment together wit the technology infrastructure that characterizes the interactions and the relations within the environment; the service dimension represents the services (being them software or not) the environment is able to provide [Nor99]. To better separate the constrains and the functionalities of a pervasive computing system, this dissertation classifies it in terms of resources, context, classification, services, coordination and application. UBIDEV, as the key result of this dissertation, introduces a unified model helping the design and the implementation of applications for heterogeneous and dynamic environments. This model is composed of the following concepts: âą Resource: all elements of the environment that are manipulated by the application, they are the atomic abstraction unit of the model. âą Context: all information coming from the environment that is used by the application to adapts its behavior. Context contains resources and services and defines their role in the application. âą Classification: the environment is classified according to the application ontology in order to ground the generic conceptual model of the application to the specific environment. It defines the basic semantic level of interoperability. âą Service: the functionalities supported by the system; each service manipulates one or more resources. Applications are defined as a coordination and adaptation of services. âą Coordination: all aspects related to service composition and execution as well as the use of the contextual information are captured by the coordination concept. âą Application Ontology: represents the viewpoint of the application on the specific context; it defines the high level semantic of resources, services and context. Applying the design paradigm proposed by UBIDEV, allows to describe applications according to a Service Oriented Architecture[Bie02], and to focus on application functionalities rather than their relations with the physical devices. Keywords: pervasive computing, homogenous environment, service-oriented, heterogeneity problem, coordination model, context model, resource management, service management, application interfaces, ontology, semantic services, interaction logic, description logic.Questa dissertazione studia il problema della eterogeneit`a nei sistemi pervasivi proponendo una infrastruttura basata su un modello orientato ai servizi. I sistemi pervasivi sono presentati come unâevoluzione naturale dei sistemi distribuiti, passando attraverso mobile computing, grazie ad una disponibilit`a ubiqua di servizi (sempre, ovunque ed in qualunque modo) e ad loro e con lâambiente stesso. Al fine di meglio comprendere i problemi legati allintrinseca eterogeneit`a dei sistemi pervasivi, dobbiamo prima descrivere la struttura fondamentale di questi sistemi classificandoli attraverso la loro dimensione fisica e quella dei loro servizi. La dimensione fisica descrive lâambiente fisico e tutti i dispositivi che fanno parte del contesto della applicazione. La dimensione dei servizi descrive le funzionalit`a (siano esse software o no) che lâambiente `e in grado di fornire [Nor99]. I sistemi pervasivi vengono cos`ı classificati attraverso una metrica pi `u formale del tipo risorse, contesto, servizi, coordinazione ed applicazione. UBIDEV, come risultato di questa dissertazione, introduce un modello uniforme per la descrizione e lo sviluppo di applicazioni in ambienti dinamici ed eterogenei. Il modello `e composto dai seguenti concetti di base: âą Risorse: gli elementi dellâambiente fisico che fanno parte del modello dellapplicazione. Questi rappresentano lâunit`a di astrazione atomica di tutto il modello UBIDEV. âą Contesto: le informazioni sullo stato dellâambiente che il sistema utilizza per adattare il comportamento dellâapplicazione. Il contesto include informazioni legate alle risorse, ai servizi ed alle relazioni che li legano. âą Classificazione: lâambiente viene classificato sulla base di una ontologia che rappresenta il punto di accordo a cui tutti i moduli di sistema fanno riferimento. Questa classificazione rappresenta il modello concettuale dellâapplicazione che si riflette sullâintero ambiente. Si definisce cos`ı la semantica di base per tutto il sistema. âą Servizi: le funzionalit`a che il sistema `e in grado di fornire; ogni servizio `e descritto in termini di trasformazione di una o pi `u risorse. Le applicazioni sono cos`ı definite in termini di cooperazione tra servizi autonomi. âą Coordinazione: tutti gli aspetti legati alla composizione ed alla esecuzione di servizi cos`ı come lâelaborazione dellâinformazione contestuale. âą Ontologia dellâApplicazione: rappresenta il punto di vista dellâapplicazione; definisce la semantica delle risorse, dei servizi e dellâinformazione contestuale. Applicando il paradigma proposto da UBIDEV, si possono descrivere applicazioni in accordo con un modello Service-oriented [Bie02] ed, al tempo stesso, ridurre lâapplicazione stessa alle sue funzionalit`a di alto livello senza intervenire troppo su come queste funzionalit` a devono essere realizzate dalle singole componenti fisiche
A Component-based Software Infrastructure for Ubiquitous Computing
(c) IEEE - The original publication is available at http://www.ieee.orgInternational audienceMultiplication of mobile devices and generalized use of wireless networks imply changes on the design and execution of distributed software applications targeting ubiquitous computing. Many strong requirements have to be addressed: heterogeneity and limited resources of wireless networks and mobile devices, networked communications between distributed applications, dynamic discovery and automatic deployment on mobile devices. In this paper, we present a component-based software infrastructure to design, discover, deploy, and execute ubiquitous contextual services, i.e. distributed applications providing services to mobile end-users but only available from a particular place. These ubiquitous contextual services are designed as assemblies of distributed software components. These assemblies are dynamically discovered according to end-users' physical location and device capabilities. Then, appropriate assemblies are automatically deployed on users' devices. We have implemented this approach (the software infrastructure and a ubiquitous application example) on top of the OMG CORBA Component Model and the OpenCCM open source platform
Plug-and-Participate for Limited Devices in the Field of Industrial Automation
Ausgangspunkt und gleichzeitig Motivation dieser
Arbeit ist die heutige Marktsituation: Starke KundenbedĂŒrfnisse
nach individuellen GĂŒtern stehen oftmals eher auf
Massenproduktion ausgerichteten Planungs- und
Automatisierungssystemen gegenĂŒber - die Befriedigung
individueller KundenbedĂŒrfnisse setzt aber FlexibilitĂ€t und
AnpassungsfÀhigkeit voraus. Ziel dieser Arbeit ist es daher,
einen Beitrag zu leisten, der es Unternehmen ermöglichen soll,
auf diese individuellen BedĂŒrfnisse flexibel reagieren zu
können. Hierbei kann es im Rahmen der Dissertation natĂŒrlich
nicht um eine Revolutionierung der gesamten Automatisierungs-
und Planungslandschaft gehen; vielmehr ist die Lösung, die der
Autor der Arbeit prÀsentiert, ein integraler Bestandteil eines
Automatisierungskonzeptes, das im Rahmen des PABADIS Projektes
entwickelt wurde: WĂ€hrend PABADIS das gesamte Spektrum von
Planung und Maschineninfrastruktur zum Inhalt hat, bezieht sich
der Kern dieser Arbeit weitestgehend auf den letztgenannten
Punkt - Maschineninfrastruktur. Ziel war es, generische
MaschinenfunktionalitÀt in einem Netzwerk anzubieten, durch das
FertigungsauftrÀge selbststÀndig navigieren. Als Lösung
prÀsentiert diese Dissertation ein Plug-and-Participate
basiertes Konzept, welches beliebige Automatisierungsfunktionen
in einer spontanen Gemeinschaft bereitstellt. Basis ist ein
generisches Interface, in dem die generellen Anforderungen
solcher ad-hoc Infrastrukturen aggregiert sind. Die
Implementierung dieses Interfaces in der PABADIS
Referenzimplementierung sowie die GegenĂŒberstellung der
Systemanforderungen und Systemvoraussetzungen zeigte, das
klassische Plug-and-Participate Technologien wie Jini und UPnP
aufgrund ihrer Anforderungen nicht geeignet sind -
AutomatisierungsgerÀte stellen oftmals nur eingeschrÀnkte
Ressourcen bereit. Daher wurde als zweites Ergebnis neben dem
Plug-and-Participate basierten Automatisierungskonzept eine
Plug-and-Participate Technologie entwickelt - Pini - die den
Gegebenheiten der Automatisierungswelt gerecht wird und
schlieĂlich eine Anwendung von PABADIS auf heutigen
Automatisierungsanlagen erlaubt. Grundlegende Konzepte von
Pini, die dies ermöglichen, sind die gesamte Grundarchitektur
auf Basis eines verteilten Lookup Service, die Art und Weise
der DienstreprÀsentation sowie die effiziente Nutzung der
angebotenen Dienste. Mit Pini und darauf aufbauenden Konzepten
wie PLAP ist es nun insbesondere möglich,
Automatisierungssysteme wie PABADIS auf heutigen Anlagen zu
realisieren. Das wiederum ist ein Schritt in Richtung
Kundenorientierung - solche Systeme sind mit Hinblick auf
FlexibilitÀt und AnpassungsfÀhigkeit gestaltet worden, um
KundenbedĂŒrfnissen effizient gerecht zu werden
MobiHealth: Ambulant Patient Monitoring Over Next Generation Public Wireless Networks
The wide availability of high bandwidth public wireless networks as well as the miniaturisation of medical sensors and network access hardware allows the development of advanced ambulant patient monitoring systems. The MobiHealth project developed a complete system and service that allows the continuous monitoring of vital signals and their transmission to the health care institutes in real time using GPRS and UMTS networks. The MobiHealth system is based on the concept of a Body Area Network (BAN) allowing high personalization of the monitored signals and thus adaptation to different classes of patients. The system and service has been trialed in four European countries and for different patient cases. First results confirm the usefulness of the system and the advantages it offers to patients and medical personnel
Plug-and-Participate for Limited Devices in the Field of Industrial Automation
Ausgangspunkt und gleichzeitig Motivation dieser
Arbeit ist die heutige Marktsituation: Starke KundenbedĂŒrfnisse
nach individuellen GĂŒtern stehen oftmals eher auf
Massenproduktion ausgerichteten Planungs- und
Automatisierungssystemen gegenĂŒber - die Befriedigung
individueller KundenbedĂŒrfnisse setzt aber FlexibilitĂ€t und
AnpassungsfÀhigkeit voraus. Ziel dieser Arbeit ist es daher,
einen Beitrag zu leisten, der es Unternehmen ermöglichen soll,
auf diese individuellen BedĂŒrfnisse flexibel reagieren zu
können. Hierbei kann es im Rahmen der Dissertation natĂŒrlich
nicht um eine Revolutionierung der gesamten Automatisierungs-
und Planungslandschaft gehen; vielmehr ist die Lösung, die der
Autor der Arbeit prÀsentiert, ein integraler Bestandteil eines
Automatisierungskonzeptes, das im Rahmen des PABADIS Projektes
entwickelt wurde: WĂ€hrend PABADIS das gesamte Spektrum von
Planung und Maschineninfrastruktur zum Inhalt hat, bezieht sich
der Kern dieser Arbeit weitestgehend auf den letztgenannten
Punkt - Maschineninfrastruktur. Ziel war es, generische
MaschinenfunktionalitÀt in einem Netzwerk anzubieten, durch das
FertigungsauftrÀge selbststÀndig navigieren. Als Lösung
prÀsentiert diese Dissertation ein Plug-and-Participate
basiertes Konzept, welches beliebige Automatisierungsfunktionen
in einer spontanen Gemeinschaft bereitstellt. Basis ist ein
generisches Interface, in dem die generellen Anforderungen
solcher ad-hoc Infrastrukturen aggregiert sind. Die
Implementierung dieses Interfaces in der PABADIS
Referenzimplementierung sowie die GegenĂŒberstellung der
Systemanforderungen und Systemvoraussetzungen zeigte, das
klassische Plug-and-Participate Technologien wie Jini und UPnP
aufgrund ihrer Anforderungen nicht geeignet sind -
AutomatisierungsgerÀte stellen oftmals nur eingeschrÀnkte
Ressourcen bereit. Daher wurde als zweites Ergebnis neben dem
Plug-and-Participate basierten Automatisierungskonzept eine
Plug-and-Participate Technologie entwickelt - Pini - die den
Gegebenheiten der Automatisierungswelt gerecht wird und
schlieĂlich eine Anwendung von PABADIS auf heutigen
Automatisierungsanlagen erlaubt. Grundlegende Konzepte von
Pini, die dies ermöglichen, sind die gesamte Grundarchitektur
auf Basis eines verteilten Lookup Service, die Art und Weise
der DienstreprÀsentation sowie die effiziente Nutzung der
angebotenen Dienste. Mit Pini und darauf aufbauenden Konzepten
wie PLAP ist es nun insbesondere möglich,
Automatisierungssysteme wie PABADIS auf heutigen Anlagen zu
realisieren. Das wiederum ist ein Schritt in Richtung
Kundenorientierung - solche Systeme sind mit Hinblick auf
FlexibilitÀt und AnpassungsfÀhigkeit gestaltet worden, um
KundenbedĂŒrfnissen effizient gerecht zu werden
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