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- Abordagens ao Problema de Escalonamento em Ambientes Reais de ProduçãoPublication . Madureira, Ana Maria; Almeida, Ana[Resumo] Num sistema de fabrico do tipo Job-Shop podem ser identificados alguns factores que contribuem para a dificuldade do processo de escalonamento, nomeadamente, a complexidade, as restrições e a incerteza. Os ambientes industriais reais são sujeitos a várias fontes de mudança, as quais são tratadas como ocorrências aleatórias, tais como, lançamento de novas ordens de fabrico, avarias, alterações de prioridades, atrasos nas operações, etc. Por escalonamento dinâmico consideramos a situação na qual um plano flexível é executado, isto é, o plano inicial é dinamicamente ajustado (re-escalonado) sempre que eventos inesperados ocorrem no sistema. Esta comunicação tem por objectivo principal efectuar uma sistematização de conceitos e classificações de problemas e tipos de escalonamento, bem como das abordagens usadas na sua resolução. Inicialmente, é apresentado o problema de escalonamento, através da caracterização dos seus elementos e da referência a algumas definições encontradas na literatura, A seguir descrevem-se algumas classificações para os problemas de escalonamento e os tipos de abordagens de resolução a adoptar. Finalmente, são propostas duas arquitecturas para a resolução do problema de escalonamento em ambientes reais de produção caracterizados por um elevado grau de dinamismo. À primeira baseada em Sistemas de Apoio à Decisão e a segunda em Algoritmos Genéticos.
- C Tutor usage in relation to student achievement and progress: A study of introductory programming courses in Portugal and SerbiaPublication . Alves, Luís; Gajić, Dušan; Henriques, Pedro Rangel; Ivančević, Vladimir; Ivković, Vladimir; Lalić, Maksim; Luković, Ivan; Pereira, Maria João Varanda; Popov, Srđan; Tavares, Paula CorreiaPrevious research studies on introductory programming courses in engineering education in Portugal and Serbia have indicated that although high motivation and high expectations seem to be reported by students, many students may fail the course. This prompted a further inquiry into student attitudes, behavior, and achievement, and it also led to the introduction of C Tutor, a widely known program visualization tool, into courses in both countries. As a result, in the present study, self-reported student achievement (grades), self-reported student progress (knowledge improvement and confidence), and self-reported usage and helpfulness of C Tutor were investigated. Anonymous data about students and their experience in the course, which also included the usage of C Tutor, were collected in a survey in Portugal and Serbia. Quantitative methods, including descriptive statistics, clustering, statistical testing of independence, and partial correlation analysis, were applied in analyses of survey data. The distribution of grades differed between the two countries, but overall attitudes were similar. Various uncovered patterns involving student attitudes and usage of C Tutor may serve as a starting point for new research studies.
- CEPP: Conversion and execution of process plansPublication . Ramos, Carlos; Figueiredo, LinoThis paper deals with a method to produce a program in numerical control (NC) language from a part drawing in a CAD system. This method is applied to any piece with revolution axis that can be machined in a CNC lathe. The method was developed with the goal of being integrated in the control software of the flexible manufacturing system existent in the CIM center of ISEP. The proposed method involves three phases, which are presented and explained.
- Computational Intelligence and Decision Making: Trends and ApplicationsPublication . Madureira, Ana Maria; Reis, Cecília; Marques, ViriatoAdvances in Computational Intelligence and Decision Making: Trends and Applications provides an overview and original analysis of new developments and applications in several areas of Computational Intelligence and Information Systems, in general. Computational Intelligence became the roadmap for engineers to develop and analyze novel techniques to solve problems in basic sciences such as physics, chemistry, biology, engineering, environment and social sciences. The material contained in this book addresses the foundations and applications of Artificial Intelligence and Decision Support Systems, Complex and Biological Inspired Systems, Simulation and Evolution of real and artificial life forms, Intelligent Models and Control Systems, Knowledge and Learning Technologies, Web Semantics and Ontologies, Intelligent Tutoring Systems, Intelligent Power Systems, Self-Organized and Distributed Systems, Intelligent Manufacturing Systems and Affective Computing. The contributions are written by international experts, who provide up-to-date aspects of the topics discussed and present recent, original insights of their own experience in these fields. Its aim is the presentation of state-of-the-art technologies in the field of Computational Intelligence as well as the discussion of new research findings in this field. The book is suitable for scientists, engineers, educators and students, as it addresses a large diversity of subjects presented in a broad band of complexity, ranging from simple natural language, found in some state-of-the-art articles, to some more complex mathematical issues, found in control applications, robotics and power systems, such as fractional calculus, fuzzy systems and rough-sets theory. Data Mining techniques, such as Support-Vector Machines and Neural Networks, are presented in application of the Biomedical and Bioinformatics fields, among others. Briefly, we believe that this book provides a good window on most of the subjects that directly or indirectly make use of Computational Intelligence, also showing the contributions that it is already giving, or can be given in a near future, for solving some of the more pressing problems of today’s world, such as energy and environment, society and economy.
- Conceitos básicos para o desenvolvimento de cursos multimédiaPublication . Vaz de Carvalho, Carlos[Excerto] Este módulo pretende descrever, de forma necessariamente sintética, as etapas associadas à criação de cursos de e-learning multimédia. No final, o leitor deverá compreender os conceitos básicos da concepção e desenvolvimento de cursos multimédia e ajustá-los de acordo com as matérias a ensinar e com o perfil dos formandos (utilizadores). Deverá ainda dominar as principais fases do desenvolvimento de cursos multimédia - análise e especificação, concepção, desenvolvimento e integração, avaliação e manutenção - incluindo a compreensão da importância de cada etapa, as ferramentas a utilizar e as competências necessárias.
- Constraint programming approach to solve facility layout design problemsPublication . Tavares, José António; Neves, José; Ramos, CarlosWe propose a methodology to solve the facility layout design problem by using constraint logic programming (CLP), which has proved to be a technology that gives good results when applied to a combinatorial problem optimisation. Methods to solve facility layout problems have to deal with a large set of factors, namely sales and production estimations, manufacturing process compatibilities, delivery dates, quality, spatial requirements, economics, management, human resources and environment. These factors make the facility layout design an extremely complex problem to solve. This complexity motivated the development of a methodology to solve the facility layout design problem using CLP.
- Cooperation in Learning Power Systems Restoration TechniquesPublication . Silva, António; Ramos, Carlos; Vale, Zita; Ramos, Carlos; Vale, ZitaAdequate training programs for power systems restoration tasks must take into account that this is a cooperative activity involving several entities. The proposed architecture of the Intelligent Tutoring System presented in this paper is based on a multi-agent system offering a simulated training environment.
- Decision support system for dynamic production schedulingPublication . Marinho, José; Ramos, Carlos; Bragança, AlexandreThis paper presents a system to support decision-making of the production manager when scheduling the manufacturing orders. This system is mainly appropriate for small and medium size enterprises with productive systems like batch or job-shop. The manufacturing orders are dynamically scheduled considering namely deadlines and resource allocation. The system combines three modules: pre-scheduling, dynamic scheduling and re-scheduling. Each module applies heuristics to select the best solutions depending on the scheduling policies defined by the production manager.
- DISTRIBUTED INTELLIGENT TUTORING SYSTEM FOR CONTROL CENTRE OPERATORS TRAININGPublication . Faria, Luiz; Ramos, Carlos; Vale, Zita; Ramos, Carlos; Vale, ZitaThe new requirements of power systems operation demand experienced and well trained operators. However, the training is not often considered a priority task, due mostly to its high costs and medium/long term results. Usually, the training programs available in industrial environment do not consider the particular training needs of each trainee. The application of the Intelligent Tutoring technology has proved to be a good alternative to the existing training approaches in the power systems area. This paper presents a Web-based Intelligent Tutoring System (ITS) to train Control Centre operators of the Portuguese electrical transmission network. One of the major advantages of the training based on the ITS technology is the ability to provide individualized training. To achieve this, our ITS maintains a trainee model, which models the trainee’s understanding of domain concepts. In this way, the paper describes a curriculum planning module used to choose the most appropriate problem to the trainee’s knowledge status. This module includes a neural network to perform a classification of each type of incident according to the trainee’s current knowledge. This paper also deals with a mechanism developed to obtain the trainee’s reasoning during problem solving.
- Distributed task schedulingPublication . Sousa, Paulo; Ramos, CarlosProposes an architecture for manufacturing enterprises based on the holonic concept. The main advantage of this approach is the decentralised, distributed nature of the system as well as its heterarchic organisation as opposed to the rigid hierarchic and centralised nature of computer integrated manufacturing (CIM). The system models products, resources and tasks and the planning, scheduling and order management functions of the enterprise. A negotiation protocol is defined for task assignment that is an extension of the contract net protocol. The protocol is based on the task-resource abstraction and is suited for negotiation in several situations not only for the dynamic scheduling of manufacturing orders. The negotiation protocol is able to handle exceptions such as machine breakdowns and rush orders.