Unlike other sciences such as Mathematics and Biology, for example, computation is presented to students at a later learning stage. Even though they are able to establish sets of procedures, it is ...alleged that in their first years of elementary school, children do not yet present cognitive structures capable of representing symbolically, through existing computer programming languages, the algorithms associated with such procedures. Within this context, there has appeared recently a robotic kit named Topobo, capable of capturing manual movements carried out in their blocks. This article presents th first result associated with the use of Topobo as a language of manual programming. The study will lead to a decompiler able to furnish, with its control flux and its structure of adequate data, the program which results from the manual manipulation of the system by the child. In a more precise form, this work anticipates the utilization of fuzzy concepts for the representation of knowledge generated from the registers of manual programming of the Topobo elements. The utilization of the fuzzy formalism will allow a qualitative and diffuse description of the knowledge, in a manner very similar to the "intuitive" and "little precise" way which human beings handle information (mainly children), leading to an adequate structure and representation of the data which are being manipulated. In addition to the formalism adopted, the article presents a 3D interface which will be helpful in the performance of the experiments. In possession of the decompiled programs, we intend to evaluate the structure of data and control fluxes which will emerge in order to identify the mental structures utilized in the construction of algorithms through manual programming by children.
Fundamentada a importância da utilização da Teoria dos Intervalos em computação científica, é realizada uma revisão da Teoria Clássica dos Intervalos, com críticas sobre as incompatibilidades ...encontradas como motivos de diversas dificuldades para desenvolvimento da própria teoria e, consequentemente, das Técnicas Intervalares. É desenvolvida uma nova abordagem para a Teoria dos Intervalos de acordo com a Teoria dos Domínios e a proposta de ACI 89, obtendo-se os Domínios Intervalares da Matemática Computacional. Introduz-se uma topologia (Topologia de Scott) compatível com a idéia de aproximação, gerando uma ordem de informação, isto é, para quaisquer intervalos x e y, diz-se que se x -c y , então y fornece mais (no mínimo tanto quanto) informação, sobre um real r, do que x. Prova-se que esta ordem de informação induz uma topologia To (topologia de Scott) , que é mais adequada para uma teoria computacional que a topologia da Hausdorff introduzida por Moore MOO 66. Cada número real r é aproximado por intervalos de extremos racionais, os intervalos de informação, que constituem o espaço de informação II(Q), superando assim a regressão infinita da abordagem clássica. Pode-se dizer que todo real r é o supremo de uma cadeia de intervalos com extremos racionais “encaixados”. Assim, os reais são os elementos totais de um domínio contínuo, chamado de Domínio dos Intervalos Reais Parciais, cuja base é o espaço de informação II (Q). Cada função contínua da Análise Real é o limite de sequências de funções contínuas entre elementos da base do domínio. Toda função contínua nestes domínios constitui uma função monotônica na base e é completamente representada em termos finitos. É introduzida uma quasi-métrica que induz uma topologia compatível com esta abordagem e provê as propriedades quantitativas, além de possibilitar a utilização da noção de sequências, limites etc, sem que se precise recorrer a conceitos mais complexos. Desenvolvem-se uma aritmética, critérios de aproximação e os conceito de intervalo ponto médio, intervalo valor absoluto e intervalo diâmetro, conceitos compatíveis com esta abordagem. São acrescentadas as operações de união, interseção e as unárias. Apresenta-se um amplo estudo sobre a função intervalar e a inclusão de imagens de funções, com ênfase na obtenção de uma extensão intervalar natural contínua. Esta é uma abordagem de lógica construtiva e computacional.
The importance of Interval Theory for scientific computation is emphasized. A review of the Classical Theory is macle, including a discussion about some incompatibities that cause problems in developing interval algorithms. A new approach to the Interval Theory is developed in the light of the Theory of Domains and according to the ideas by Acióly ACI 89, getting the Interval Domains of Computational Mathematics. It is introduced a topology (Scott Topology), which is associated with the idea of approximation, generating an information order, that is, for any intervals x and y one says that if x -c y, then "the information given by y is better or at least equal than the one given by x". One proves that this information order induces a To topology (Scott's topology) which is more suitable for a computation theory than that of Hausdorff introduced by Moore MOO 66. This approach has the advantage of being both of constructive logic and computational. Each real number is approximated by intervals with rational bounds, named information intervals of the Information Space II(Q), eliminating the infinite regression found in the classical approach. One can say that every real a is the supreme of a chain of rational intervals. Then, the real numbers are the total elements of a continuous domain, named the Domain of the Partial Real Intervals, whose basis is the information space II (Q). Each continuous function in the Real Analysis is the limit of sequences of continuous functions among any elements which belong to the base of the domain. In these same domains, each continuous function is monotonic on the base and it is completely represented by finite terms. It is introduced a quasi-metric that leads to a compatible topology and supplies the quantitative properties. An arithmetic, some approximation criteria, the concepts of mean point interval, absolute value interval and width interval are developed and set operations are added. The ideas of interval functions and the inclusion of ranges of functions are also presented, and a continuous natural interval extension is obtained.
Este trabalho consiste no desenvolvimento de uma metodologia para a obtenção de representações construtivas de sistemas ordenados de 2ª ordem, baseadas em estruturas de espaços coerentes, com ...aplicação fundamental na Computação Científica e Matemática Intervalar. Obtêm assim uma representação global para os objetos ditos infinitos relativamente ao conteúdo de informação, como números reais e intervalos reais, de tal forma que possam ser definidos modelos semânticos adequados para os processos computacionais envolvendo tais objetos. Esta representação construtiva é denominada de global, pois é realizada em dois níveis distinguíveis, compreendendo não somente a construção interna dos objetos, no contexto de uma da estrutura de informação, mas também sua estrutura externa de aplicação. A estrutura de informação tem caráter compatível com uma abordagem domínio-teorética, e a estrutura de aplicação e determinada pelo use pretendido do sistema representado. Existe um relacionamento entre os dois níveis de construção, garantindo que cada componente da estrutura de aplicação tenha uma representação interna na estrutura de informação. Os sistemas de representação global resultantes são denominados então espaços coerentes bi-estruturados, e tem a característica adicional de serem gerados por um sistema ordenado basico de universo enumerável. A estrutura de informação é um espaço coerente, com funções lineares e uma estrutura topológica de informação compatível. A estrutura de aplicação - algébrica, de ordem, relacional, funcional, de medidas, topológica, dentre outras - é obtida por um processo construtivo a partir da estrutura do sistema basico. Um espaço coerente bi-estruturado, obtido por esse processo de construção, é a representação global de um dado sistema ordenado de 2ª ordem quando possível recuperar este sistema através do subsistema dos objetos totais do espaço, pela determinação de isomorfismos para a estrutura de aplicação. Da mesma forma, estabelecendo também isomorfismos para o subsistema dos intervalos de elementos do conjunto universo do sistema que esta sendo representado, esse subsistema pode ser recuperado como o subsistema dos objetos quasi-totais do espaço coerente. Apresenta-se também uma abordagem categórica para o processo de construção global, mostrando se que ele determina uma adjunção entre duas subcategorias da categoria SO2 dos sistemas ordenados de 2ª ordem A metodologia proposta se mostrou particularmente interessante na construção do conjunto dos números reais e do conjunto de intervalos reais. Para estes sistemas introduziu-se também uma subestrutura elementar de medidas, pela definição, de forma generalizada, das funções valor absoluto, distância e diâmetro. Foi desenvolvida uma estrutura topológica para os espaços coerentes bi-estruturados, que caracteriza-se também por apresentar dois níveis que se inter-relacionam. Para obter uma caracterização topológica de informação desenvolveu-se a noção de espaços de vizinhanças lineares. No sentido de se obter a caracterização topológica de aplicação, obteve-se, em cada etapa da construção, um espaço de vizinhanças gerado pela função distância generalizada com uma topologia de aplicação associada. Conexões entre as representações de reais e de intervalos de reais e aspectos de computabilidade são referidas de modo preliminar, sugerindo-se este tema como trabalho futuro. Possíveis aplicações dos espaços coerentes bi-estruturados e do processo de construção global a outras áreas da Ciência da Computação são indicadas no final do trabalho.
The aim of this work is to develop a methodology to obtain constructive representations of second order ordered systems, based on coherence space structures, with the main application in Scientific Computation and Interval Mathematics. A global representation for the so-called infinite objects considering the information content they represent, in particularly real numbers and real intervals, is obtained, so that suitable semantical models for real and interval computational processes can be provided. This constructive representation is said to be global. since it is performed in two distinguished levels, dealing with the internal construction of the objects, in the context of an information structure, and, on the other hand, building an external application structure. The information structure is compatible with a domain-theoretic approach, and the application structure is established according the intended usage of the represented system. There exists a relationship between the two levels of the construction, guaranteeing that each component of the application structure should have an internal representation in the information structure. The resulting global representation systems are called bi-structured coherence spaces, and they have the additional feature of being generated by a basic ordered system having a denumerable universe. The information structure is a coherence space endowed with linear functions and a compatible information topological structure. The (algebraic, ordered, relational, functional, measure, topological, etc.) application structure is obtained by the construction process, considering the structure of the basic system as the start point. A bi-structured coherence space, obtained by this construction process, is said to be the global representation of a given second order ordered system if it is possible to recover the latter by the subsystem of the total objects of the former, defining isomorphisms related to the application structure. Following the same pattern, establishing isomorphisms for the subsystem of the intervals of elements of the represented system, it is possible to recover it as the subsystem of quasi-total objects of the bi-structured coherence space. A categorical approach is also presented and it is shown that the global construction process determines an adjunction between two subcategories of the category SO2 of the second order ordered systems. The proposed methodology was shown to be particularly interesting when constructing the sets of real numbers and real intervals. For these systems, an elementary measure structure was introduced in a generalised approach, defining generalised distance, diameter and absolute value functions. The bi-structured coherence spaces were given an interrelated two-level topological characterisation. In order to obtain an information topological characterisation the concept of linear neighbourhood systems was introduced. For the application topological characterisation, at each step of the construction, a neighbourhood system generated by the generalised distance function, with an associated topology, was defined. A brief analysis concerning the connections among other representations of real and real intervals and computability aspects is presented. Other possible applications in Computer Science are indicated.
Brain-computer interface technologies, such as steady-state visually evoked potential, P300, and motor imagery are methods of communication between the human brain and the external devices. Motor ...imagery-based brain-computer interfaces are popular because they avoid unnecessary external stimuli. Although feature extraction methods have been illustrated in several machine intelligent systems in motor imagery-based brain-computer interface studies, the performance remains unsatisfactory. There is increasing interest in the use of the fuzzy integrals, the Choquet and Sugeno integrals, that are appropriate for use in applications in which fusion of data must consider possible data interactions. To enhance the classification accuracy of brain-computer interfaces, we adopted fuzzy integrals, after employing the classification method of traditional brain-computer interfaces, to consider possible links between the data. Subsequently, we proposed a novel classification framework called the multimodal fuzzy fusion-based brain-computer interface system. Ten volunteers performed a motor imagery-based brain-computer interface experiment, and we acquired electroencephalography signals simultaneously. The multimodal fuzzy fusion-based brain-computer interface system enhanced performance compared with traditional brain-computer interface systems. Furthermore, when using the motor imagery-relevant electroencephalography frequency alpha and beta bands for the input features, the system achieved the highest accuracy, up to 78.81% and 78.45% with the Choquet and Sugeno integrals, respectively. Herein, we present a novel concept for enhancing brain-computer interface systems that adopts fuzzy integrals, especially in the fusion for classifying brain-computer interface commands.
This paper presents a way to quantify objective dependence relations between agents of a society in order to measure the degree of dependence established between them. The quantification is performed ...on specially defined dependence situation graphs. A way is presented to refine objective degrees of dependence into subjective ones, through the consideration of subjective aspects of the dependence relationships. The paper also shows how to measure the dependence that the society as a whole has on each agent that participates in it, and how to measure the negotiation power of each agent in such society
This paper refines a previously introduced procedure to quantify objective dependence relations between agents of a multiagent system. The quantification of the dependence relations is performed on a ...specially defined form of reduced dependence graphs, called dependence situation graphs. The paper also shows how the procedure can be used to determine a measure of the dependence that a society as a whole has on each agent that participates in it and, correlatively, a measure of the negotiation powers of the agents of such society. The procedure is also extended to allow for the refinement of the objective degrees of dependence into subjective ones, through the use of auxiliary coefficients that can represent some subjective aspects of the dependence relationships. A sample calculation of objective degrees of dependence and negotiation powers of agents of a simple multiagent system is presented, and a hint is given on how degrees of dependence could be used to support social reasoning processes.
This paper introduces an approach for the self-regulation of personality-based social exchange processes in multiagent systems, where a mechanism of social equilibrium supervision is internalized in ...the agents with the goal of achieving the equilibrium of the exchanges, guaranteeing the continuity of the interactions. The decision process concerning the best exchanges that an agent should propose to its partner is modeled as one Partially Observable Markov Decision Processs (POMDPs) for each agent personality trait. Each POMDP is decomposed into sub-POMDPs, according to the current balance of exchange values. Based on the relationship that may be established between POMDPs and Belief-Desire-Intention (BDI) architectures, the paper introduces an algorithm to map the policy graphs of the sub-POMDPs to BDI plans, allowing for a library of BDI plans. Simulations were carried out considering different degrees of supervision.
In this paper we review two approaches to the regulation of agent interactions based on Piaget's theory of social exchanges. These approaches model a social equilibrium supervisor, that, at each ...time, recommends certain exchange actions to the agents, in order to lead the interaction towards the equilibrium, regarding the balance of the exchange values involved in the exchanges. One approach uses a centralized supervisor, that has access to all agents' internal state, and give recommendations to lead the agents to an equilibrium in their exchanges. This centralized supervisor uses a Qualitative Interval Markov Decision Process (QI-MDP), to determine the best recommendation for the agents. The other approach is a decentralized one, in which each agent has an equilibrium supervisor internalized in it. In this model, each supervisor in each agent has access to the agent's internal state where he is in, but is unable to access the internal states of the other agents. In order to give exchange recommendations to the supervised agent, the internalized supervisor uses BDI (Beliefs, Desires, Intentions) plans derived from the optimal interaction policy provided by a Partially Observable Markov Decision Process (POMDP). We present an analysis of the two approaches, aiming at the identification of which features of each approach can be used to improve the other one.
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