Connection space approach to ambiguities of gauge theories

Two distinct gauge potentials can have the same field strength, in which case they are said to be copies of each other. The consequences of this ambiguity for the general affine space A of gauge potentials are examined. Any two potentials are connected by a straight line in A, but a straight line going through two copies either contains no other copy or is entirely formed by copies. Copyright © 2005 Hindawi Publishing Corporation.

An evaluation of the productivity of mischocyttarus drewseni in a semi-urban environment (Hymenoptera: Polistinae)

The biology and productivity of Myschocytarus drewseni were studied in semi urban conditions at Rio Claro, S P - Brazil. We observed 51 nest foundations, of which 24 (47%) were destroyed or predated, 13 (25.5 %) were abandoned and 14 (27.5%) completed the cycle. The life-span of colonies ranged from 44-427 days with a mean of 216.7 ± 140.6 days, producing 8-390 cells with a mean of 125.7 ± 137.9 cells, and 2-303 adults with a mean of 89.4 ± 110.36 adults. We observed a maximum of 3 utilizations/cell. This showed that the species presents asynchronous foundation and abandoningoccurs throughout the year. Also, the chance of a colony utilizing the same cells two or three times for adult production is highly dependent on the colony size/age, and the relation between them is positive, meaning that there is a greater chance of cell re-utilization in larger/older colonies.

Potential scenarios for Internet use in the mathematics classroom

Research on the influence of multiple representations in mathematics education gained new momentum when personal computers and software started to become available in the mid-1980s. It became much easier for students who were not fond of algebraic representations to work with concepts such as function using graphs or tables. Research on how students use such software showed that they shaped the tools to their own needs, resulting in an intershaping relationship in which tools shape the way students know at the same time the students shape the tools and influence the design of the next generation of tools. This kind of research led to the theoretical perspective presented in this paper: knowledge is constructed by collectives of humans-with-media. In this paper, I will discuss how media have shaped the notions of problem and knowledge, and a parallel will be developed between the way that software has brought new possibilities to mathematics education and the changes that the Internet may bring to mathematics education. This paper is, therefore, a discussion about the future of mathematics education. Potential scenarios for the future of mathematics education, if the Internet becomes accepted in the classroom, will be discussed. © FIZ Karlsruhe 2009.

Morphological routine proposal to extraction of highways in digital images of high resolution

This research proposes to apply techniques of Mathematics Morphology to extract highways in digital images of high resolution, targeting the upgrade of cartographic products. Remote Sensing data and Mathematical Morphological techniques were integrated in the process of extraction. Mathematical Morphology's objective is to improve and extract the relevant information of the visual image. In order to test the proposed approach some morphological operators related to preprocess, were applied to the original images. Routines were implemented in the MATLAB environment. Results indicated good performances by the implemented operators. The integration of the technologies aimed to implement the semiautomatic extraction of highways with the purpose to use them in processes of cartographic updating.

Trade in services in Latin America and the Caribbean: an analysis of recent trends

Includes bibliography

Boundary of the rauzy fractal sets in ℝ×ℂgenerated by p(x) = x 4- x 3 - x 2 -x- 1

We study the boundary of the 3-dimensional Rauzy fractal ε ⊂ ℝ×ℂ generated by the polynomial P(x) Dx 4-x 3-x 2-x-1. The finite automaton characterizing the boundary of ε is given explicitly. As a consequence we prove that the set ε has 18 neighboors where 6 of them intersect the central tile ε in a point. Our construction shows that the boundary is generated by an iterated function system starting with 2 compact sets.

Wavelets in a problem of signal processing

In this work a new method is proposed for noise reduction in speech signals in the wavelet domain. The method for signal processing makes use of a transfer function, obtained as a polynomial combination of three processings, denominated operators. The proposed method has the objective of overcoming the deficiencies of the thresholding methods and the effective processing of speech corrupted by real noises. Using the method, two speech signals are processed, contaminated by white noise and colored noises. To verify the quality of the processed signals, two evaluation measures are used: signal to noise ratio (SNR) and perceptual evaluation of speech quality (PESQ).

Narrativas sobre a prática de ensino de matemática de professores dos anos iniciais do ensino fundamental

Pós-graduação em Educação Matemática - IGCE

A noção de função em Frege

Pós-graduação em Educação Matemática - IGCE

The economics of climate change in Latin America and the Caribbean: Paradoxes and challenges of sustainable development

The robust growth of Latin American and Caribbean economies in recent years has led to an improvement in economic and social conditions in the region. It has also had collateral negative effects, however, such as more air pollution in urban areas and a serious deterioration of various natural assets, including non-renewable resources, water resources and forests. There are economies and societies within the region that are highly vulnerable to all sorts of adverse impacts of climate change, and whose production structures and consumption patterns still tend to leave a large carbon footprint. This situation has reached the point of undermining the foundations of the region’s economic buoyancy. Latin America and the Caribbean therefore needs to make the transition in the years to come towards a sustainable form of development that will preserve its economic, social and natural assets for future generations and leave them with a legacy of a more equal, more socially inclusive, low-carbon form of economic growth. Viewed from this standpoint, the climate change challenge is also a sustainable development challenge, and if it is to be addressed successfully, a global consensus that recognizes the asymmetries and paradoxes of the problem will have to be reached..

Fundamentos teóricos do método de resolução de problemas ampliados

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Intercâmbios acadêmicos matemáticos entre EUA e Brasil: uma globalização do saber

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Educação matemática e totalidade: um estudo crítico epistemológico

Pós-graduação em Educação Matemática - IGCE

Sentidos de percepção e educação matemática: geometria dinâmica e ensino de funções com auxílio de representações dinâmicas

Pós-graduação em Educação Matemática - IGCE

A formação do professor de matemática para a escola inclusiva: os projetos político curriculares das IES públicas do município de Belém-PA em análise

O estudo trata da formação inicial de professores de matemática das IES públicas do município de Belém-PA, estabelecendo como objetivos identificar as características da educação e escola inclusivas; descrever, a partir da vigência da Lei 9.394/96 (LDBEN), que prescrições oficiais foram definidas nessas propostas para tornarem o licenciado em matemática apto para trabalhar na escola inclusiva; identificar que propostas curriculares as IES públicas de Belém elaboraram para seus cursos de licenciatura em matemática, a partir da atual legislação, no sentido de atender as prescrições legais para a atuação desse profissional na escola inclusiva; e, identificar quais as concepções de competências e habilidades foram adotadas nos PPC dos cursos de licenciatura em matemática das IES públicas UFPA, UEPA e IFPA, no município de Belém-PA, em função da necessidade de formar o professor de matemática inclusivo. O estudo mostrou a necessidade de que a educação inclusiva seja considerada como um construto social flexível e não limitado ao trato da pessoa com deficiência, o que incide na necessidade de uma formação inicial que busque fomentar no futuro professor uma atuação que tenha a diversidade como princípio de atuação profissional. O estudo mostra, também, que as competências, enquanto eixo estruturador dessa formação, presentes nas prescrições oficiais vigentes para a educação, traz uma matriz de competência funcionalista, fundada nas psicologias behaviorista e cognitivista, matriz essa que exerceu influências significativas em uma das propostas de formação pesquisadas (UFPA), ao passo que a proposta de formação da UEPA não atendeu as prescrições oficiais no sentido de adotar as competências como eixo nuclear de formação, bem como quanto a uma formação de professores na perspectiva da Educação Inclusiva. A terceira proposta (IFPA) buscou atender as prescrições oficiais vigentes, tanto quanto à adoção das competências, como eixo de formação, quanto uma formação de professores de matemática na perspectiva da educação inclusiva, adotando, para tanto, como um diferencial significativo, competências e concepções que trazem a aprendizagem fundada nas interações entre os atores envolvidos no processo educativo, onde se observou a preponderância da matriz construtivista de competências, sob as bases da Psicologia Sócio- Histórica de Vygotsky, Leontiev e Luria.