Evandro Costa

Recommendations in Online Discussion Forums for E-Learning Systems

In this paper, we outline the importance of discussion fora for e-learning applications. Due to a weak structure or size of the discussion forum, recommendations are required in order to help learners finding relevant information within a forum. We present a generic personalization framework and evaluate the framework based on a recommender architecture for the e-learning focused discussion forum Comtella-D. In the evaluation, we examine different sources of user feedback and the required amount of user interaction to provide recommendations. The outcomes of the evaluation serve as source for a personalization rule, which selects the most appropriate recommendation strategy based on available user input data. We furthermore conclude that collaborative filtering techniques can be utilize successfully in small data sets, like e-learning related discussion fora.

Steps, techniques, and technologies for the development of intelligent applications based on Semantic Web Services: A case study in e-learning systems

Semantic Web Services domain has gained special attention in academia and industry. It has been adopted as a promise to enable automation of all aspects of Web Services provision and uses, such as service creation, selection, discovery, composition, and invocation. However, the development of intelligent systems based on Semantic Web Services (SWS) is still a complex and time-consuming task, mainly with respect to the choice and integration of technologies. In this paper, we discuss some empirical issues associated with the development process for such systems and propose a systematic way for building intelligent applications based on SWS by providing the development process with steps, techniques and technologies. In addition, one experiment concerning the implementation of a real e-learning system using the proposed approach is described. The evaluation results from this experiment showed that our approach has been effective and relevant in terms of improvements in the development process of intelligent applications based on SWS.

A survey of security in multi-agent systems

Multi-agent systems (MAS) are a relatively new software paradigm that is being widely accepted in several application domains to address large and complex tasks. However, with the use of MAS in open, distributed and heterogeneous applications, the security issues may endanger the success of the application. The goal of this research is to identify the security issues faced by MAS and to survey the current state of the art of this field of knowledge. In order to do it, this paper examines the basic concepts of security in computing, and some characteristics of agents and multi-agent systems that introduce new threats and ways to attack. After this, some models and architectures proposed in the literature are presented and analyzed.

A framework for building web mining applications in the world of blogs: A case study in product sentiment analysis

Recently there has been much interest in electronic commerce applications that use data mining techniques to explore datasets in the social media context. However, most of the applications have already been developed in an ad hoc manner, mainly, due to the lack of adequate tools, yielding difficulties in customizing applications and requesting high time consuming for constructing and maintaining these applications. This work addresses these problems and proposes a software framework for building Web mining applications in the blog world. The architecture of the proposed framework combines the use of blog crawling and data mining algorithms, in order to provide a complete and flexible solution for building general-purpose Web mining applications. The framework flexibility allows some important customizations, such as the construction of adapters for reading text from different blogs, and the use of different pre-processing techniques and data mining algorithms. In order to improve the efficacy of information extraction from blogs, ontology is used in the blogs description. For this, there are software agents responsible for tracking and indexing blogs related to a specific tag and for mining blog datasets. Moreover, web services are used for encapsulating existing tools and maximize reuse. This framework has been instantiated in order to be applied for helping the blog users to effectively find out relevant information in the blog world. The focus of this paper is on describing the novel software architecture of the general framework (blog crawling and data mining) providing detailed information about the data mining sub-framework, which uses the semantic web services technology for automating service composition and consists on the main research contribution. A case study of an e-commerce application for analyzing the users sentiment regarding specific products is reported and its results considers the effort reduction when creating a web mining application by using the proposed integrated frameworks and existing data mining tools, as well as a qualitative analysis related to quality aspects of the developed application, such as the evolution impact.

Estado da Arte em Web Semântica e Web 2.0: Potencialidades e Tendências da Nova Geração de Ambientes de Ensino na Internet

As tecnologias educacionais com base na Web tem obtido excelente resultados nas ultimas decadas. Atualmente, diversos cursos no exterior e no Brasil sao oferecidos na modalidade “educacao a distância” onde a Internet e a plataforma base de comunicacao e interacao entre alunos e professores. Com os grandes avancos da Internet e a necessidade de oferecer formas mais eficazes de aprendizagem na Web, duas linhas de pesquisa estao em crescente expansao. A primeira delas e a Web Semântica que desenvolve tecnologias que permitem ao computador compartilhar e manipular as informacoes contidas na Web de forma adequada e inteligente. Com o uso desta tecnologia ambientes de aprendizagem ou agentes de software podem interagir entre si, trocar informacoes e auxiliar professores e alunos a selecionar, combinar e classificar o conteudo disponivel na Web. E a segunda e a Web 2.0, ou web Social, onde os usuarios sao beneficiados por diversas ferramentas para compartilhar e construir “conhecimento” de forma simples, interativa e colaborativa. O objetivo deste trabalho e estimular as pesquisas nacionais nestas areas apresentando o estado da arte sobre o uso da Web Semântica e da Web 2.0 no cenario educacional e a recente intersecao destas tecnologias para promover a nova geracao de ambientes educacionais para Web 3.0.

Modelos e Ferramentas para a Construção de Sistemas Educacionais Adaptativos e Semânticos

This research examines the design and effective development of adaptive and se- mantic Web-based educational systems, integrating artificial intelligence techniques and semantic Web-based technologies in order to provide a new generation of vir- tual learning environments. In this sense, results obtained from three case studies (within Math and Medicine domains) are provided to evaluate the feasibility of the work.

Educational resources recommendation system based on agents and semantic web for helping students in a virtual learning environment

This work proposes an agent-based system for helping students in the knowledge building process by providing them with recommendations of papers and blogs. The interaction starting point involves a blog context focused on a specific domain. Then, the teacher posts a topic in this blog and students express their opinions about this topic. Afterwards, the system monitors the interaction process aiming to mine the discussion to extract important attributes and information. Then, the recommender system retrieves relevant material to support dynamic interactions in the learning environment. Thus, two situations were defined one, being that the system helps the students by finding and recommending relevant and related blogs. The other, being that the system helps students by recommending papers from a digital library to provide them with formal opinions about the target topic, aiming at enriching their learning experiences. The proposed system with a case study and empirical results are described.

From a Tridimensional View of Domain Knowledge to Multi-agent Tutoring System

This paper focus on results related to the design of a model of a Computer-based Interactive Learning Environment adopting a multi-agent approach. Questions related to why and how adopt this approach are addressed. We begin presenting and emphasizing the definition of both a view of the domain knowledge structure and a model for it. Then, we show the consequences of this toward the definition of a multi-agent system, leading to a complete learning environment. Related to this environment we define its characteristics and its agent model. Moreover, we discuss both the interaction model among agents and between a human learner and the System. Finally, we focus on the interactions among agents during Problem solving activities, discussing the interaction language and the interaction protocols.

RetriBlog: An architecture-centered framework for developing blog crawlers

Blogs have become an important social tool. It allows the users to share their tastes, express their opinions, report news, form groups related to some subject, among others. The information obtained from the blogosphere may be used to create several applications in various fields. However, due to the growing number of blogs posted every day, as well as the dynamicity of the blogosphere, the task of extracting relevant information from the blogs has become difficult and time consuming. In this paper, we use information retrieval and extraction techniques to deal with this problem. Furthermore, as blogs have many variation points is required to provide applications that can be easily adapted. Faced with this scenario, the work proposes RetriBlog, an architecture-centered framework for the development of blog crawlers. Finally, it presents an evaluation of the proposed algorithms and three case studies.

Modeling JADE Agents from GAIA Methodology under the Perspective of Semantic Web

Building multi-agent software systems is pointed out as a high complex task and researchers have raised different issues for building several applications. Therefore several AOSE methodologies and MAS frameworks have been proposed to facilitate the hard task of modeling and building high complex systems. However, those methodologies in an attempt to model complex systems end up being hard to use and to ensure the consistency between each part. On the other hand, ontologies have been considered useful for representing the knowledge of software engineering techniques and methodologies in order to provide an unambiguous terminology that can be shared, reusable, and ensure the consistence between the concepts involved. This paper proposes ontologies for specifying agents through the use of GAIA methodology, JADE Framework and SWRL rules to map the instances from GAIA ontology to JADE ontology. Finally, it is presented a case study and a discussion to demonstrate their use.