The number concept : its origin and development /

Includes bibliographical references and indexes.

Production system model of children's development of number concepts

The purpose of the present research study was to produce a global, cumulative model of number concept development for children between the ages of two and eight years old. The theoretical and methodological orientation of this study was greatly influenced by Richard Young's production system analysis of seriation by young children (Young, 1971, 1976) and by Newell's (1973) seminal paper, ‘You can't play twenty questions with nature and win’. The methodology used in this investigation thus was as follows. A series of complex number tasks encompassing many aspects of the concept of number were developed. Five children aged between three and seven years then were videotaped while performing some of these complex number tasks. From a detailed protocol analysis of the video-recordings, computer simulation models written in the production system language PSS3 (Ohlsson, 1979) were produced. Specific production system models were produced for each of following aspects of the children's number knowledge: (i) sharing of discrete quantities; (ii) comparison of shares; and (iii) conservation/addition/subtraction of number. These domain-specific models were based on the converging experimental evidence obtained from each of the children’s responses to variants of the complex number tasks. Each child thus received a different set of problems which were chosen systematically in order to clarify particular features of the child's abilities. After a production system model for each child had been produced within a domain, these models were compared and contrasted. From this analysis, developmental trends within the domain were identified and discussed. The research and educational implications of these developmental trends then were discussed. In the concluding parts of this study, the children's domain-specific production system models were cumulated into global, comprehensive models which accurately represented their behaviour in a variety of number tasks. These comprehensive models were compared and contrasted and general developmental trends in young children's number knowledge were identified and discussed.

Number : a link between divine intelligence and human. An argument /

Mode of access: Internet.

Aprendizagem dos números reais : um estudo com alunos do 9.º ano

Relatório da Prática de Ensino Supervisionada, Ensino de Matemática, Universidade de Lisboa, 2013

A aprendizagem dos números racionais através das conexões entre as suas representações:uma experiência de ensino no 2º ciclo do ensino básico

Tese de doutoramento, Educação (Didática da Matemática), Universidade de Lisboa, Instituto de Educação, 2014

q-Analog of the gap equation for cuprates

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Conceito de número: uma contribuição da análise comportamental da cognição

Fundamenta-se o presente estudo na análise comportamental da cognição, cujas formulações permitem compreender o conceito de número como uma rede de relações entre estímulos e/ou entre estímulos e respostas. O desempenho de seis crianças de três a sete anos de idade e uma adolescente portadora da Síndrome de Down foi analisado em uma série de tarefas consideradas pré-requisitos para aprendizagens matemáticas mais complexas. Para isso, foi utilizada uma versão informatizada do procedimento de discriminação condicional em um contexto de matching to sample. As relações presentes, ausentes e as não bem estabelecidas no repertório dos sujeitos foram graficamente representadas em diagramas que configuram-se como que retratos do repertório individual. Tal recurso facilita o planejamento do ensino estratégico de umas poucas relações com vistas à emergência das relações ausentes e/ou o fortalecimento daquelas nas quais o sujeito apresenta desempenho pobre, de modo a completar a rede. A guisa de conjeturas, apresentam-se sugestões de intervenção.

A noção de função em Frege

Pós-graduação em Educação Matemática - IGCE

Uma proposta para utilização do computador no processo de ensino e aprendizagem dos primeiros números do sistema hindu-arábico

The aim of this work is presenting the development and the results of a research, which focus of interest has been the making of softwares that could help the process of teaching and learning of the hindu-arabic numerals system, on children in the alphabetical stage. Since the most important presupposes to this work are the development of the number concept according to Jean Piaget (1986-1980) and the reality of the classroom, then three different moments have been fixed: the creation of a beginning scheme of computer activities; the aplication of these activities on children in the alphabetical stage; and, finally, an analysis of the limits and possibilities of these activities while an environment cause of actions that would benefit the process of teaching and learning of the mentioned content. Finally, based on the anlysis of the results obtained, the next step was fixing a more consistant set of computer activities, which makes up a proposal to the use of computer in the process of teaching and learning of the first hindu-arabic numbers

Design concept evaluation based on rough number and information entropy theory

Concept evaluation at the early phase of product development plays a crucial role in new product development. It determines the direction of the subsequent design activities. However, the evaluation information at this stage mainly comes from experts' judgments, which is subjective and imprecise. How to manage the subjectivity to reduce the evaluation bias is a big challenge in design concept evaluation. This paper proposes a comprehensive evaluation method which combines information entropy theory and rough number. Rough number is first presented to aggregate individual judgments and priorities and to manipulate the vagueness under a group decision-making environment. A rough number based information entropy method is proposed to determine the relative weights of evaluation criteria. The composite performance values based on rough number are then calculated to rank the candidate design concepts. The results from a practical case study on the concept evaluation of an industrial robot design show that the integrated evaluation model can effectively strengthen the objectivity across the decision-making processes.

The IMC concept meets political marketing : building brand relationships

There is a need to take a fresh look at the traditional application of the marketing concept to political marketing. As many businesses have learned, Integrated Marketing Communications (IMC) practices and principles will help them to build customer relationships and profitable brands. Political marketing must also change with the times and implement IMC practices toward building and nourishing brand relationships with voters and other important stakeholders. The nature of the contribution of this paper is the identification of a gap in the political marketing literature - the stagnation of political marketing at the 4P's marketing concept, and to play a role in the future development of political marketing. In recent developments, it is seen that there is a gradual movement away from this traditional marketing theory. There are a growing number of academics who have approached very closely to the IMC concept or aspects of it, but have not however embraced or have been reluctant to, the prospect of applying it to political marketing. IMC is a practical, logical and ultimately inevitable future for political marketing.

Soil carbon saturation: Linking concept and measurable carbon pools

The soil C saturation concept suggests a limit to whole soil organic carbon (SOC) accumulation determined by inherent physicochemical characteristics of four soil C pools: unprotected, physically protected, chemically protected, and biochemically protected. Previous attempts to quantify soil C sequestration capacity have focused primarily on silt and clay protection and largely ignored the effects of soil structural protection and biochemical protection. We assessed two contrasting models of SOC accumulation, one with no saturation limit (i.e., linear first-order model) and one with an explicit soil C saturation limit (i.e., C saturation model). We isolated soil fractions corresponding to the C pools (i.e., free particulate organic matter POM], microaggregate-associated C, silt- and clay-associated C, and non-hydrolyzable C) from eight long-term agroecosystern experiments across the United States and Canada. Due to the composite nature of the physically protected C pool, we firactioned it into mineral- vs. POM-associated C. Within each site, the number of fractions fitting the C saturation model was directly related to maximum SOC content, suggesting that a broad range in SOC content is necessary to evaluate fraction C saturation. The two sites with the greatest SOC range showed C saturation behavior in the chemically, biochemically, and some mineral-associated fractions of the physically protected pool. The unprotected pool and the aggregate-protected POM showed linear, nonsaturating behavior. Evidence of C saturation of chemically and biochemically protected SOC pools was observed at sites far from their theoretical C saturation level, while saturation of aggregate-protected fractions occurred in soils closer to their C saturation level.

A new pulsed power supply topology based on positive buck-boost converters concept

Improving efficiency and flexibility in pulsed power supply technologies is the most substantial concern of pulsed power systems specifically with regard to plasma generation. Recently, the improvement of pulsed power supply has become of greater concern due to the extension of pulsed power applications to environmental and industrial areas. With this respect, a current source based topology is proposed in this paper as a pulsed power supply which gives the possibility of power flow control during load supplying mode. The main contribution in this configuration is utilization of low-medium voltage semiconductor switches for high voltage generation. A number of switch-diode-capacitor units are designated at the output of topology to exchange the current source energy into voltage form and generate a pulsed power with sufficient voltage magnitude and stress. Simulations carried out in Matlab/SIMULINK platform as well as experimental tests on a prototype setup have verified the capability of this topology in performing desired duties. Being efficient and flexible are the main advantages of this topology.