23 research outputs found
Context-Aware and Adaptable eLearning Systems
The full text file attached to this record contains a copy of the thesis without the authors publications attached. The list of publications that are attached to the complete thesis can be found on pages 6-7 in the thesis.This thesis proposed solutions to some shortcomings to current eLearning architectures. The proposed DeLC architecture supports context-aware and adaptable provision of eLearning services and electronic content. The architecture is fully distributed and integrates service-oriented development with agent technology. Central to this architecture is that a node is our unit of computation (known as eLearning node) which can have purely service-oriented architecture, agent-oriented architecture or mixed architecture. Three eLeaerning Nodes have been implemented in order to demonstrate the vitality of the DeLC concept. The Mobile eLearning Node uses a three-level communication network, called InfoStations network, supporting mobile service provision. The services, displayed on this node, are to be aware of its context, gather required learning material and adapted to the learner request. This is supported trough a multi-layered hybrid (service- and agent-oriented) architecture whose kernel is implemented as middleware. For testing of the middleware a simulation environment has been developed. In addition, the DeLC development approach is proposed. The second eLearning node has been implemented as Education Portal. The architecture of this node is poorly service-oriented and it adopts a client-server architecture. In the education portal, there are incorporated education services and system services, called engines. The electronic content is kept in Digital Libraries. Furthermore, in order to facilitate content creators in DeLC, the environment Selbo2 was developed. The environment allows for creating new content, editing available content, as well as generating educational units out of preexisting standardized elements. In the last two years, the portal is used in actual education at the Faculty of Mathematics and Informatics, University of Plovdiv. The third eLearning node, known as Agent Village, exhibits a purely agent-oriented architecture. The purpose of this node is to provide intelligent assistance to the services deployed on the Education Pportal. Currently, two kinds of assistants are implemented in the node - eTesting Assistants and Refactoring eLearning Environment (ReLE). A more complex architecture, known as Education Cluster, is presented in this thesis as well. The Education Cluster incorporates two eLearning nodes, namely the Education Portal and the Agent Village. eLearning services and intelligent agents interact in the cluster
Intelligent Car Parking Locator Service
This paper presents an InfoStation-based multi-agent system facilitating a Car Parking Locator service
provision within a University Campus. The system network architecture is outlined, illustrating its functioning
during the service provision. A detailed description of the Car Parking Locator service is given and the system
entities’ interaction is described. System implementation approaches are also considered
Agent-Oriented Middleware Supporting Delivery of Mobile Elearning Services
Within project Distributed eLearning Center (DeLC) we are
developing a system for distance and eLearning, which offers fixed and mobile
access to electronic content and services. Mobile access is based on InfoStation
architecture, which provides Bluetooth and WiFi connectivity. On InfoStation
network we are developing multi-agent middleware that provides context-aware,
adaptive and personalized access to the mobile services to the users. For more
convenient testing and optimization of the middleware a simulation environment,
called CA3 SiEnv, is being created
InfoStation-based Adaptable Provision of m Learning Services: Main Scenarios
This paper presents an adaptable InfoStation-based multi-agent system facilitating the mobile
eLearning (mLearning) service provision within a University Campus. A horizontal view of the network
architecture is presented. Main communications scenarios are considered by describing the detailed interaction of
the system entities involved in the mLearning service provision. The mTest service is explored as a practical
example. System implementation approaches are also considered
Intelligent Systems
This book is dedicated to intelligent systems of broad-spectrum application, such as personal and social biosafety or use of intelligent sensory micro-nanosystems such as "e-nose", "e-tongue" and "e-eye". In addition to that, effective acquiring information, knowledge management and improved knowledge transfer in any media, as well as modeling its information content using meta-and hyper heuristics and semantic reasoning all benefit from the systems covered in this book. Intelligent systems can also be applied in education and generating the intelligent distributed eLearning architecture, as well as in a large number of technical fields, such as industrial design, manufacturing and utilization, e.g., in precision agriculture, cartography, electric power distribution systems, intelligent building management systems, drilling operations etc. Furthermore, decision making using fuzzy logic models, computational recognition of comprehension uncertainty and the joint synthesis of goals and means of intelligent behavior biosystems, as well as diagnostic and human support in the healthcare environment have also been made easier
Formal specification of an intelligent message notification service in an infostation-based mLearning System using CCA.
The Calculus of Context-aware Ambients (CCA in short)
has been proposed as a notation that is suitable to model
mobile applications that are context-aware. This paper
considers a real-world case study of an infostation-based
mLearning system in which mobile devices such as hand-set
phones, PDA’s and laptops can access a number of services
and communicate to each other within a university campus.
Such a dynamic system must enforce complex policies
to cope with mobility and context-awareness. We show
how policies can be formalised using CCA, and validated
using the execution environment of CCA. We illustrate how
properties can be validated using our approach
Policy-based approach for context-aware systems
Pervasive (ubiquitous) computing is a new paradigm where the computers are submerged into the background of the everyday life. One important aspect of pervasive systems is context-awareness. Context-aware systems are those that can adapt their behaviours according to the current context. Context-aware applications are being integrated into our everyday activity aspects such as: health care, smart homes and transportations. There exist a wide range of context-aware applications such as: mobile phones, learning systems, smart vehicles.
Some context-aware systems are critical since the consequence of failing to identify a given context may be catastrophic. For example, an auto-pilot system is a critical context-aware system; it senses the humidity, clouds, wind speed and accordingly adjusts the altitude, throttle and other parameters. Being a critical context-aware system has to be provably correct.
Policy-based approaches has been used in many applications but not in context-aware systems. In this research, we want to discover the anatomy (i.e. architecture, structure and operational behaviour) of policy-based management as applied to context-aware systems, and how policies are managed within such a dynamic system.
We propose a novel computational model and its formalisation is presented using the Calculus of Context-aware Ambients (CCA). CCA has been proposed as a suitable mathematical notation to model mobile and context-aware systems. We decided to use CCA due to three reasons: (i) in CCA, mobility and context-awareness are primitive constructs and are treated as first-class citizens; (ii) properties of a system can be formally analysed; (iii) CCA specifications are executable, and thus, leading to rapid prototyping and early validation of the system properties. We, then show how policies can be expressed in CCA. For illustration, the specification of the event-condition-action (ECA) conceptual policy model is modelled in CCA in a natural fashion.
We also propose a policy-based architecture for context-aware systems, showing its different components, and how they interact. Furthermore, we give the specification of the policy enforcement mechanism used in our proposed architecture in CCA.
To evaluate our approach, a real-world case study of an infostation-based mobile learning (mLearning) system is chosen. This mLearning system is deployed across a university campus to enable mobile users to access mobile services (mServices) represented by course materials (lectures, tests and tutorials) and communication services (intelligent message notification and VoIP). Users can access the mServices through their mobile devices (Hand-set phones, PDAs and laptops) regardless of their device type or location within a university campus. We have specified the mLearning system in CCA (i.e. specification based on policies of the mServices), afterwards, the specification is simulated using the CCA interpreter tool.
We have developed an animation tool specially designed for the mLearning system.
The animation tool provides graphical representation of the CCA processes. In terms of safety and liveness, some important properties of the mLearning system have been validated as a proof of concept
Formal Specification of CA-UCON model using CCA
A Context-Aware Usage CONtrol (CAUCON)
model is an extension of the traditional UCON
model which enables adaptation to environmental changes
in the aim of preserving continuity of usage in a pervasive
computing system. When the authorisations and
obligations requirements are met by the subject and
the object, and the conditions requirements fail due to
changes in the environment or the system context, CAUCON
model triggers specific actions to adapt to the new
situation. Besides the data protection, CA-UCON model so
enhances the quality of services, striving to keep explicit
interactions with the user at a minimum. This paper
proposes a formal specification of the CA-UCON model in
the Calculus of Context-aware Ambients (CCA in short).
This enables formal analysis of the CA-UCON model using
the execution environment of CCA. For illustration, some
properties of the CA-UCON model are validated for a
ubiquitous learning system