Costin Badica

Towards a Unified Learning Style Model in Adaptive Educational Systems

Accommodating learning styles in adaptive educational systems represents an important step towards providing individualized instruction. The paper summarizes the main results reported in the literature, as well as the main criticisms of the current approaches. Thus, most of the adaptive educational systems to date are based on a single learning style model and the diagnosis is done explicitly, by means of a psychological questionnaire. The lack of an integrative, comprehensive learning style model and the questionable validity and reliability of the measuring instruments are two important problems of this approach. In this context, we advocate the use of a unified learning style model, which exhibits the following properties: i) it integrates the most relevant characteristics from several models in the literature; ii) it includes e-learning specific aspects (technology related preferences); iii) it is stored as a set of learning characteristics, not as a stereotyping model. Moreover, the student diagnosis is to be done implicitly, based on analyzing her/his interactions with the system.

Mobile agents in a multi-agent e-commerce system

Among features often attributed to software agents are autonomy and mobility. Autonomy of e-commerce agents involves adaptability to engage in negotiations governed by mechanisms not known in advance, while their mobility entails such negotiations taking place at remote locations. This paper aims at combining adaptability with mobility, by joining rule-based mechanism representation with modular agent design, and at UML-formalizing selected aspects of the resulting system. Furthermore, we discuss the issue of agent mobility and argue why such agents have been proposed for the system under consideration.

Rules for Learner Modeling and Adaptation Provisioning in an Educational Hypermedia System

This note presents our initial proposal for capturing knowledge required for learner modeling and adaptation provisioning in an educational hypermedia system using a rule-based approach. Rules have been categorized as i) modeling rules - necessary for the identification of the learner style based on observed learning preferences and ii) adaptation rules - necessary for content adaptation based on learning style and/or learning preferences.

Role activity diagrams as finite state processes

Many formal modelling notations for business processes have been proposed during the last decade. They can be broadly classified into high-level visual notations, with an intuitive meaning, mainly addressed to the business management community and low-level foundational notations, with a detailed and formal semantics, mainly addressed to the computer science community. Role activity diagrams are a popular high-level visual notation for capturing the dynamics and role structure of an organization. This paper establishes that role activity diagrams have a formal semantics as well and thus making them suitable to formal verification. The result is obtained by mapping of a role activity diagram model to a process algebra model. Process algebras are mathematical languages for the specification and understanding of concurrent and cooperating computational processes.

UML models of agents in a multi-agent e-commerce system

Recently a new model agent-based e-commerce system was proposed, in which rule-based mechanism representation was combined with lightweight modular mobile agent design. Furthermore, need for agent mobility as the optimal solution to satisfy user needs was discussed. The aim of this paper is to introduce UML formalizations of most important agents that appear in the model system as well as presentation of its complete action diagram

The design and implementation of an agent-based auction service

In this paper, we present the architecture, design and implementation of an agent-based service for automated auctions. The presentation covers the conceptual architecture, types of agents, agent communication and design and implementation issues. The experimental results to assess the performance of the service in terms of latency and throughput as functions of the number of auction participants and number of simultaneously active auctions are also included. The results confirmed that while the solution allows an increased level of flexibility and reusability as compared with existing approaches, it still suffers from performance and scalability problems that we plan to address in the near future.

Adaptive Information Provisioning in an Agent-Based Virtual Organization- Preliminary Considerations

In this note we consider design of a information provisioning subsystem for an agent-based virtual organization. Flexible delivery of information is based on matching of ontologically demarcated resource profiles, work contexts, and domain specific knowledge.

Description and Organization of Instructional Resources in an Adaptive Educational System Focused on Learning Styles

In this note we present an intelligent way of organizing learning material in an adaptive educational hypermedia system. We describe the use of instructional metadata which facilitates both the detection of student learning style and the application of various adaptation techniques. The advantage of our approach is that it is independent of a particular learning style model. Furthermore, the author has to supply only the annotated learning content (the static description) while the adaptation logic (the dynamic description) is provided by the system.

Effectiveness of solving traveling salesman problem using Ant Colony Optimization on distributed multi-agent middleware

Recently we have setup the goal of investigating new truly distributed forms of Ant Colony Optimization.We proposed a new distributed approach for Ant Colony Optimization (ACO) algorithms called Ant Colony Optimization on a Distributed Architecture (ACODA). ACODA was designed to allow efficient implementation of ACO algorithms on state-of-the art distributed multi-agent middleware. In this paper we present experimental results that support the feasibility of ACODA by considering a distributed version of the Ant Colony System (ACS). In particular we show the effectiveness of this approach for solving Traveling Salesperson Problem by comparing experimental results of ACODA versions of distributed ACS with distributed random searches on a high-speed cluster network.

Evaluation of a Learning Management System for Adaptivity Purposes

Adaptive Web-based educational systems are a continuously growing area of research. However, despite the relatively numerous approaches, adaptivity from the point of view of student learning styles is not properly addressed. We therefore plan to create a framework for devising and deploying university courses that will take into account not only students knowledge level but also his/her cognitive traits, interests and motivation. A first step towards achieving our objective is the choice of an existing LMS, suitable for being extended into an adaptive one. The netUniversite platform proved to be a successful candidate.