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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A study of gravitational properties of the Kaehler equation

Talebaoui, W. A. O. January 1987 (has links)
No description available.
2

Computing automorphism groups of projective planes

Unknown Date (has links)
The main objective of this thesis was to find the full automorphism groups of finite Desarguesian planes. A set of homologies were used to generate the automorphism group when the order of the plane was prime. When the order was a prime power Pa,a ≠ 1 the Frobenius automorphism was added to the set of homologies, and then the full automorphism group was generated. The Frobenius automorphism was found by using the planar ternary ring derived from a coordinatization of the plane. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2013.
3

Rhythms Of Times And Places

Pope, Bettye 10 March 2012 (has links)
Artist Statement I am inspired by living in multiple environments and experiencing many regions of the United States. My imagery varies from references to landscapes to geometric abstractions of quilt patterns. My media consists of acrylics, oils, and pastels on supports including fabric, canvas, or paper. Mixed media allows me to add multiple layers in creating visual textures, depth, and energy to draw in my viewers. The media is glazed, flowed, dripped, sprayed, rolled, scraped, and scrubbed into my interpretations of natural elements and geometric patterns. My landscape paintings are of observations of nature, and I attempt to capture the power, motion, and energy of a moment in time. I paint from memory and purposely filter the images, simplifying and strengthening the focus of the captured moment. Rhythmic patterns in nature and seasonal light on the land are sources of my visual stimulation. My affinity for geometric shapes and patterns is sometimes expressed in abstract paintings of quilt patterns. I form rhythmic compositions and enhance the patterns with delicate brushwork and several glazed layers for added surface interest. These patterns of quilts are also reminiscent of landscapes from a bird’s eye view.
4

Integrando a geometria com a álgebra na construção de expressões algébricas

Cardia, Luciana Simoneti Ferreira 17 May 2007 (has links)
Made available in DSpace on 2016-04-27T16:58:23Z (GMT). No. of bitstreams: 1 Luciana Simoneti Ferreira Cardia.pdf: 3597373 bytes, checksum: f8e76960406f82f881cdef8076eea698 (MD5) Previous issue date: 2007-05-17 / The objective of this research is to study phenomena that influence the teaching and learning of the concept of algebraic expressions in Elementary Education (students aged 7-15). It presents a teaching proposal for the conception of Algebraic Expressions; uses the Geometry as a tool of construction and provide a reflection about the learning of this concept through a teaching didactic sequence involving the concept of area as principal tool to construction of mathematic knowledge, as well as, the processes of decomposition and composition of planes figures, equicomposition of figures and area equivalents. The following hypothesis guided the development of the different activities proposed: choose of problem situations involving determinate on of the areas of geometrical figures, in particular the area of rectangle, allowing comparisons these of figures using, area as magnitude. to study area as a magnitude and leading to the construction of generalized algebraic expressions. a proposal for teaching and learning the concept of algebraic expressions, making use of the geometric concepts, like area concept, decomposing and composing processes of plan figures, this allows the student favorable conditions to learning this concept. This research is based mainly on two theories: the Tool-Object Dialectic and the Change of Pictures of Régine Douady (1987) and Registries of Semiotic Representation of Raymond Duval (1993). The adopted methodology follows the principles of the Didactical Engineering. The research involved teachers and students of the 7th grade of Elementary Education / O objetivo dessa pesquisa é o estudo dos fenômenos que interferem no sistema de ensino-aprendizagem do conceito de expressões algébricas no Ensino Fundamental. Além disso, apresenta uma proposta de ensino do conceito de expressão algébrica, utilizando a Geometria como instrumento de construção e proporciona uma reflexão sobre a aprendizagem desse conteúdo por meio de uma seqüência didática envolvendo o conceito de área como instrumento principal de construção do conhecimento matemático, assim como os processos de decomposição e composição de figuras planas, eqüicomposição de figuras, equivalência de áreas. As seguintes hipóteses nortearam o desenvolvimento das diferentes atividades propostas: a escolha de situações-problema envolvendo determinação de áreas de figuras geométricas, em particular área de retângulos, possibilitando as comparações dessas figuras em termos de área como grandeza. estudar a área como grandeza, levando à construção das expressões algébricas generalizadas. uma proposta de ensino-aprendizagem do conceito de expressão algébrica, utilizando-se dos conceitos geométricos, como o conceito de área, os processos de decomposição e composição de figuras planas, possibilitando ao aluno condições favoráveis à aprendizagem deste conceito. Esta pesquisa está fundamentada principalmente em duas teorias: a Dialética Ferramenta-Objeto e a Mudança de Quadros de Régine Douady (1986) e na teoria de Registros de representação Semiótica de Raymond Duval (1993,1994,1995). A metodologia adotada seguiu os princípios da Engenharia Didática. A pesquisa envolveu professores do Ensino Fundamental e Médio e foi aplicada numa turma de alunos da 7ª série do Ensino Fundamental
5

Sistem?tica integrativa de Cichlasoma orientale Kullander 1983 e Crenicichla menezesi Ploeg 1991 (Teleostei: Cichlidae) das bacias hidrogr?ficas do Nordeste do Brasil

Berbel Filho, Waldir Miron 30 April 2014 (has links)
Made available in DSpace on 2014-12-17T15:49:15Z (GMT). No. of bitstreams: 1 WaldirMBF_DISSERT.pdf: 3558667 bytes, checksum: 3035c50ccf49225a3c8264f6c395bf14 (MD5) Previous issue date: 2014-04-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Understanding the historical and ecological relationships which are influent in current biological diversity is one of the most challenging tasks of evolutionary biology. Recent systematics emphasizes the need of integrative approaches to delimit different lineages and species. The northeastern Brazil, mostly placed in Caatinga biome, is characterized by a semi-arid weather, low precipitation and seasonal behavior of rivers. This region is regarded lacking as ichthyological knowledge and one of the most threatened by anthropic activities. Further, will be affected by a massive water diverpsion work that will transfer waters from S?o Francisco basin, to other major four basins: Jaguaribe, Apodi-Mossor?, Piranhas-A?u and Paraiba do Norte. Loss of diversity and richness, hibridizitation, community interactions changes, population homogenization, changes in water quality and flow regime, are examples of environmental impacts already related with similar works. The present study aims to investigate morphological and molecular variation of Cichlasoma orientale Kullander 1983 and Crenicichla menezesi Ploeg 1991, two cichlid species present in northeastern Brazil basins. Further, the study aims to evaluate the influence of geomorphological and climatic processes in this variation, and point some possible impacts of the artificial connectivity which can be brought by S?o Francisco interbasin water transfer to their population dynamics. Geometric morphometrics and phylogeographical analysis were used to investigate the populations from three different hydrological regions. Our results showed a significant morphological variation of populations from basins that are involved in the S?o Franscisco s diversion project, not related to an ancient separation between populations, emphasizing morphological variation which could represent a set of plastic responses to the variable hydrological regime in Northeastern Brazil. The role of plastical responses in naturally variable habitats as well as the potential disturbs that could be brought by the interbasin water transfer works are discussed here. Further, our molecular data allowed us to make inferences about species distribution and their taxonomy, and identification of a potential new species of Crenicichla for S?o Francisco river basin. Our data also allowed to identify some shared haplotypes for both species, which could be related to lineage sorting scenarios or recent gene flow between populations. However a strong structure in most of the pairwise comparisons between populations for both species was revealed. Climatic events such as Atlantic forest regression during the Pleistocene, sea level fluctuations and dispersion by paleorivers in the mouth of Apodi-Mossor? river, and neotectonic events regulating the connection between drainages are likely to have had a contribution for the actual lineages distribution in northeastern Brazil. Further, analysis of molecular variation (AMOVA and SAMOVA) showed that the actual basin s isolation is an important factor to molecular variation, in spite of the signal of recent contact between some basins. Different genetic diversity patterns between species could be related to multiple historic events of colonization, basins landscapes or biological differences. The present study represents the first effort of integrative systematics involving fish species of northeastern Brazil, and showed important morphological and molecular patterns which could be irrecoverably affected by the artificial connection that might be caused by the S?o Francisco interbasin water transfer / O Nordeste brasileiro, majoritariamente imerso no bioma Caatinga, se caracteriza pelo clima semi-?rido, baixa precipita??o e um regime de rios intermitentes. Quanto ao conhecimento ictiofaun?stico, a regi?o ? considerada uma das maiores lacunas mundiais, e uma das mais amea?adas pelas atividades antr?picas. Al?m disso, a regi?o est? passando por obras de transposi??o, que ligar? ?guas do rio S?o Francisco com quatro bacias da regi?o: Jaguaribe, Apodi-Mossor?, Piranhas-A?u e Para?ba do Norte. Perda de diversidade, hibridiza??o de esp?cies, altera??es de comunidade, homogeneiza??o de popula??es, altera??o de qualidade e regime de fluxo de ?gua, s?o impactos ambientais j? atribu?dos a empreendimentos similares. O presente estudo objetiva investigar a varia??o morfol?gica e molecular de Cichlasoma orientale Kullander 1983 e Crenicichla menezesi Ploeg 1991, duas esp?cies com ampla distribui??o ao longo das bacias do Nordeste brasileiro, atrav?s de m?todos de sistem?tica integrativa. Al?m disso, o estudo visa analisar a influ?ncia de fatores clim?ticos e geomorfol?gicos nesta varia??o, e apontar poss?veis impactos da conex?o artificial das bacias envolvidas na transposi??o do rio S?o Francisco. Para estes fins, foram utilizadas an?lises de morfometria geom?trica e filogeogr?ficas com indiv?duos de tr?s ecorregi?es hidrogr?ficas do Nordeste brasileiro. Nossos resultados mostraram que h? uma significativa varia??o morfol?gica nas bacias envolvidas na transposi??o do rio S?o Francisco, que n?o est? ligada ? uma separa??o ancestral das bacias, evidenciando uma varia??o morfol?gica que pode representar um conjunto de respostas pl?sticas ?s constantes transforma??es principalmente relacionadas ao regime h?drico da regi?o. O papel de respostas pl?sticas em ambientes naturalmente vari?veis, assim como o potencial impacto do dist?rbio no regime h?drico a ser trazido pela transposi??o do rio S?o Francisco, s?o discutidos. Al?m disso, nossos dados moleculares permitiram fornecer mais informa??es sobre a distribui??o das esp?cies e sua taxonomia, incluindo a identifica??o de uma potencial nova esp?cie de Crenicichla na bacia do rio S?o Francisco. Os dados tamb?m mostraram alguns hapl?tipos compartilhados para ambas as esp?cies, que podem representar cen?rios incompletos de separa??o de linhagens ou fluxo g?nico recente entre popula??es, por?m forte estrutura??o entre a maior parte das bacias. Eventos clim?ticos como a regress?o da Mata Atl?ntica durante o Pleistoceno, flutua??es do n?vel do mar e a dispers?o por paleorios na por??o estuarina das bacias que desaguam no litoral norte da regi?o nordeste, al?m de eventos neotect?nicos envolvendo captura de cabeceiras, parecem ter contribu?do para a atual distribui??o de linhagens destas esp?cies no Nordeste brasileiro. Al?m disso, an?lises de vari?ncia molecular (AMOVA e SAMOVA) evidenciaram que a atual conjuntura das bacias se mostrou um fator importante para a varia??o molecular, apesar da indica??o de compartilhamento recente entre algumas bacias. Diferen?as de padr?es de diversidade intrapopulacional entre as esp?cies podem estar relacionadas a m?ltiplos eventos hist?ricos de coloniza??o, ou ? diferen?as biol?gicas. O presente estudo representa o primeiro esfor?o de sistem?tica integrativa com esp?cies da ictiofauna continental do Nordeste brasileiro, e revelou varia??es morfol?gicas e moleculares entre drenagens isoladas que podem ser irrecuperavelmente afetadas com a conex?o artificial destas bacias a partir das obras de transposi??o do rio S?o Francisco
6

Divergências morfométricas e comportamentais em Apis mellifera L. (Hymenoptera:apidae)

Sousa, Arlik Rafael Santiago de 31 July 2014 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Bees of the genus Apis are widely distributed throughout the tropical regions of the planet, playing fundamental role as pollinators. In Brazil they are a polihibrid formed by the crossbreed of African subspecies Apis mellifera scutellata and European subspecies, where due generalist habits the introgression of alleles of the African subspecies has led to a predominance of the your characteristics in relation to European subspecies. The scope of this work was to characterize the divergence among 71 colonies of Africanized honey bees located in three distinct ecoregions (Forest zone, Ecotone and Semiarid) of the State of Sergipe Brazilian northeast, through morphological and behavioral analyses, in order to assess the relationship between the effects of seasonality and the different patterns morphoclimatic ecoregions in morphology, behavior and distribution of these groups of bees. In this work we used geometric morphometric techniques observing the anatomical landmarks of the wing venation with the aid of software Tps / DIG and evaluation of hygienic behavior by pin-killing method in two distinct seasonal periods, the dry and rainy. The correlation between the hygienic behavior indexes and environmental variables was obtained by Spearman correlation and the causal relations by path analysis, with the aid of software R. The morphometric analyzes were performed by means of multivariate analysis with the aid of software MORPHOJ and PAST. Thus, the results of this study demonstrated that the high gene flow evidenced between studied colonies and pronounced differences in apiaries and ecoregions with influence of altitude on shape (r=0,06239; p= 0.05) and size (0.001) contributed therefore for the separation of these groups as result of phenotypic plasticity rather than genetic divergence among populations of Africanized honey bees. Furthermore, the results also demonstrated significant difference in hygienic behavior of these populations between the dry and rainy season (p= 0,022; α=0,05) and between ecoregions (p=0,001; α=0,05) with the influence of temperature (ρ=0,065; p=0,471; α=0,05) and altitude (ρ=-0,294; p=0,001 α=0,05) upon pluviosity (ρ=0,274; p=0,002; α=0,05) that demonstrated be the main modulator of hygienic behavior, thus reinforcing the influence of environmental factors on the expression of this trait. Therefore, it is concluded by the influence of stochastic factors in the morphology, behavior and distribution of Africanized honey bees, where polyphenisms found denote the high genetic variability of these populations, a fact that can be exploited in future conservation, handling and breeding programs. / As abelhas do genero Apis estao amplamente distribuidas pelas regioes tropicais do planeta, sendo fundamentais no papel de polinizadores. No Brasil, estas sao um poliibrido formado pelo cruzamento entre a subespecie africana Apis mellifera scutellata e as subespecies europeias. Devido a habitos generalistas, a introgressao de alelos da subespecie africana tem levado a uma predominancia nas caracteristicas desta em relacao as europeias. O presente trabalho teve como escopo a caracterizacao da divergencia entre 71 colonias de A. mellifera africanizadas, situadas em tres distintas ecorregioes (Zona da Mata, Agreste e Sertao) do Estado de Sergipe, nordeste do Brasil, por meio de analises morfologicas e comportamentais, com o objetivo de avaliar as relacoes entre os efeitos da sazonalidade e dos distintos padroes morfoclimaticos das ecorregioes na morfologia, comportamento e distribuicao desses grupos de abelhas. Neste estudo foram utilizadas tecnicas de morfometria geometrica, com observacao dos marcos anatomicos da venacao alar, com o auxilio do software Tps/DIG e avaliacao do comportamento higienico pelo metodo de perfuracao de crias em dois periodos estacionais, o seco e o chuvoso. A correlacao entre os indices de comportamento higienico e as variaveis ambientais foi obtida por meio da correlacao de Spearman e as relacoes de causalidade por meio da analise de trilha, com o auxilio do software R. As analises morfometricas foram realizadas por meio de tecnicas de analise multivariada, com o auxilio dos softwares MORPHOJ e PAST. Assim, os resultados deste trabalho demonstraram que o intenso fluxo genico evidenciado entre as colonias estudadas e as diferencas pronunciadas nos distintos apiarios e ecorregioes, com influencia da altitude na forma (r=0,06239; p= 0.05) e tamanho (0.001) contribuiram, portanto, para a separacao desses grupos como resultado da plasticidade fenotipica e nao de divergencia genetica entre as populacoes de abelhas africanizadas. Alem disso, os resultados tambem demonstraram haver diferenca significativa no comportamento higienico dessas populacoes, entre os periodos seco e chuvoso (p= 0,022 ¿=0,05) e entre as ecorregioes (p=0,001; ¿=0,05), com influencia da temperatura ( Ï=0,065 p=0,471; ¿=0,05) e altitude ( Ï=-0,294; p=0,001; ¿=0,05) sobre a pluviosidade ( Ï=0,274 p=0,002; ¿=0,05) sendo esta o principal modulador do comportamento higienico, reforcando a influencia de fatores ambientais na manifestacao dessa caracteristica. Portanto, conclui-se pela influencia de fatores estocasticos na morfologia, comportamento e distribuicao das abelhas africanizadas, onde os polifenismos encontrados denotam a grande variabilidade genetica dessas populacoes, fato esse que pode ser explorado em futuros programas de conservacao, manejo e melhoramento.

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