To see the other types of publications on this topic, follow the link: Disjuncts.
Dissertations / Theses on the topic 'Disjuncts'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Disjuncts.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Barrio, García Alejandra. "L’expression de la modalité épistémique en espagnol : étude diachronique des modalisateurs de doute." Thesis, Paris 10, 2017. http://www.theses.fr/2017PA100079/document.
Full textAbstract:
Notre thèse s’intéresse aux processus de création des adverbes de modalité dubitative dans l’histoire de l’espagnol. À l’aide des corpus de la Real Academia Española, CORDE et CREA, nous étudions du point de vue diachronique les principaux adverbes et locutions adverbiales qui expriment le doute du locuteur par rapport au contenu propositionnel de l’énoncé : por (a)ventura, acaso, quizá(s), puede que, tal vez, a lo mejor, lo mismo et igual. Notre recherche comprend ainsi la quasi-totalité de l’histoire de la langue espagnole, depuis le XIIe siècle, où l’on retrouve déjà quizá, jusqu’au XXe avec le surgissement de lo mismo et igual. Ces expressions ont des origines diverses – constructions verbales, syntagmes prépositionnels, etc.–mais elles fonctionnent toutes initialement comme des éléments intégrés dans la structure syntaxique de la phrase, dans laquelle elles transmettent des notions qui relèvent du hasard, de la temporalité, de la comparaison, etc. Ce travail s’occupe donc, dans un premier temps, d’élucider les chemins que ces expressions ont empruntés pour parvenir à fonctionner comme des adverbes de modalité dubitative et, dans un deuxième temps, il rend compte des relations qu’entretiennent ces expressions adverbiales, puisque, malgré leur apparente synonymie et interchangeabilité, ces adverbes diffèrent sur certains aspects les uns des autres. À cet égard, l’étude diachronique des contextes d’apparition, des valeurs et des fonctions des éléments qui ont intégré le paradigme nous permet de comprendre les différentes nuances et possibilités d’emploi qui caractérisent ces expressions une fois qu’elles acquièrent leur rôle d’adverbes de modalité dubitativeThis thesis aims to study the creation processes of the modal probability adverbs in the history of Spanish. Thus, from the diachronic point of view, we study, with the help of the Real Academia Española corpora, CORDE and CREA, the main adverbs and adverbial locutions that express the speaker's doubt regarding the propositional content of the statement: por (a)ventura, acaso, quizá(s), puede que, tal vez, a lo mejor, lo mismo and igual. Our research covers practically the whole history of the Spanish language, from the twelfth century, in which quizá is documented, until the twentieth, when the most recent adverbs of probability, lo mismo and igual, arise. These expressions have different origins – verbal constructions, prepositional phrases, etc. – but all function initially as integrated elements in the syntactic structure of the sentence, in which they transmit notions related to chance, temporality, comparison, etc. This work, therefore, is concerned firstly with elucidating the paths followed by these expressions in order to function as probability adverbs and, secondly, it gives account of the relations that lie between these adverbial expressions. Despite their apparent synonymy and interchangeability, these adverbs differ from one another in some respects. In this sense, the diachronic study of the contexts of appearance, the meanings and the functions of the elements that have integrated the paradigm allow us to understand the different nuances and possibilities of use that characterize these expressions once they acquire their role of modal probability adverbs
Esta tesis se ocupa del estudio de los procesos de creación de los adverbios de modalidad dubitativa en la historia del español. Con la ayuda de los corpus de la Real Academia Española, CORDE y CREA, estudiamos desde el punto de vista diacrónico los principales adverbios y locuciones adverbiales que expresan la duda del hablante con respecto al contenido proposicional del enunciado: por (a)ventura, acaso, quizá(s), puede que, tal vez, a lo mejor, lo mismo e igual. Nuestra investigación abarca así prácticamente toda la historia de la lengua española, desde el siglo XII, en el que ya se documenta quizá, hasta el XX, en el que surgen los adverbios de duda más recientes lo mismo e igual. Las expresiones estudiadas tienen orígenes diversos –construcciones verbales, sintagmas preposicionales, etc.–, pero todas funcionan inicialmente como elementos integrados en la estructura sintáctica de la frase, en la que transmiten nociones relativas al azar, a la temporalidad, a la comparación, etc. Este trabajo se ocupa, pues, en primer lugar, de elucidar los caminos que han seguido estas expresiones para llegar a funcionar como adverbios de modalidad dubitativa y, en segundo lugar, de dar cuenta de las relaciones que mantienen estas expresiones adverbiales, ya que, a pesar de su aparente sinonimia e intercambiabilidad, estos adverbios difieren unos de otros en algunos aspectos. En este sentido, el estudio diacrónico de los contextos de aparición, valores y funciones de los elementos que han integrado el paradigma nos permite comprender los diferentes matices y posibilidades de uso que caracterizan a estas expresiones una vez que adquieren su papel de adverbios de modalidad dubitativa
2
Feitosa, Rodrigo dos Santos Machado. "Revisão taxonômica e análise filogenética de Heteroponerinae (Hymenoptera, Formicidae)." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/59/59131/tde-17072012-114907/.
Full textAbstract:
Heteroponerinae Bolton (2003) compreende três gêneros de formigas: Acanthoponera Mayr, Aulacopone Arnol\'di e Heteroponera Mayr. Acanthoponera é exclusivamente Neotropical, enquanto Heteroponera mostra uma distribuição disjunta nas Américas e Oceania. O gênero Aulacopone, de posição incerta na subfamília, é conhecido por uma única espécie representada por um par de rainhas coletadas por volta da década de 1930 em duas localidades no sudoeste da Ásia (Azerbaijão). O presente estudo representa a primeira revisão taxonômica global de Heteroponerinae em nível específico e a primeira tentativa de se analisar as relações filogenéticas internas da subfamília com base em caracteres morfológicos externos de todos os táxons nela incluídos. O estudo dos terminais utilizados na análise filogenética resultou em uma matriz com 101 caracteres, sendo 50 destes empregados pela primeira vez em uma análise cladística envolvendo formigas. A análise filogenética demonstra a monofilia de Heteroponerinae, com pelo menos quatro sinapomorfias sustentando esta hipótese. Os gêneros Acanthoponera e Heteroponera também são monofiléticos em todas as topologias aqui encontradas. As relações internas apontam para uma posição basal do gênero paleártico Aulacopone, que figura como grupo-irmão do clado Acanthoponera + Heteroponera. Ainda assim, devido à falta de caracteres que ofereçam maior suporte à inclusão de Aulacopone em Heteroponerinae, este gênero é mantido como incertae sedis na subfamília. A relativa falta de resolução nas relações internas em Acanthoponera e nos ramos mais apicais de Heteroponera não impede o reconhecimento de algumas linhagens como evolutivamente independentes. A presença destas linhagens em pelo menos duas regiões biogeográficas e a proximidade filogenética encontrada entre grupos neotropicais e australianos revelam um interessante cenário biogeográfico a ser investigado. Após o exame de 33 dos 36 espécimes-tipo designados para as espécies e subespécies de Heteroponerinae, seis espécies são reconhecidas para o gênero Acanthoponera, das quais duas são descritas como novas. Heteroponera apresenta 21 espécies (seis delas descritas aqui pela primeira vez), sete das quais restritas à Região Australiana (três novas) e 14 exclusivamente neotropicais (três novas). Heteroponera flava Kempf é sinonimizada sob H. panamensis (Forel) e H. georgesi Perrault passa a ser sinônimo júnior de H. microps Borgmeier. Indivíduos de castas e sexos ainda não registrados (incluindo machos, gines e operárias) são aqui descritos pela primeira vez para diferentes espécies de Heteroponerinae. Novos registros de localidades expandem significativamente a distribuição conhecida para a maior parte das espécies. Observações de campo aliadas a dados de rótulo de espécimes de museus fornecem importantes informações adicionais acerca da história natural do grupo. Larvas de Heteroponerinae são predominantemente predadoras, alimentando-se de pequenos artrópodes coletados pelas operárias. Ocasionalmente, adultos podem se alimentar dos líquidos (hemolinfa) resultantes das feridas provocadas no tegumento das presas caçadas por operárias e de exudatos vegetais no caso de espécies arborícolas. Os ninhos de Heteroponera são encontrados no solo ou na vegetação e podem abrigar colônias com algumas dezenas a poucas centenas de indivíduos, sendo que as operárias forrageiam preferencialmente no solo. Acanthoponera nidifica e forrageia exclusivamente em árvores. Com relação à estratégia reprodutiva, algumas espécies de Heteroponera podem apresentar gines ergatóides dividindo a função reprodutiva com as gines aladas na mesma colônia, enquanto em outras espécies as gines aladas foram completamente substituídas por ergatóides. Como uma próxima etapa para a compreensão da história evolutiva deste grupo sugere-se uma análise das relações internas dos gêneros através de ferramentas moleculares e um estudo dos padrões biogeográficos de Heteroponerinae.Heteroponerinae Bolton (2003) comprises three ant genera: Acanthoponera Mayr, Aulacopone Arnol\'di and Heteroponera Mayr. Acanthoponera is exclusively Neotropical, while Heteroponera shows a disjunct distribution in the Americas and Australia. The position of Aulacopone within the subfamily is uncertain as it is known by a single species represented by two gynes collected around the 1930s in two localities in Southeast Asia (Azerbaijan). This study represents the first comprehensive taxonomic revision of Heteroponerinae at specific level and the first attempt to analyze the internal phylogenetic relationships of the subfamily based on the external morphology of all heteroponerine taxa. The study of the species used in the phylogenetic analysis resulted in a matrix with 101 characters, of which 50 are used for the first time in a cladistic analysis involving ants. The phylogenetic analysis demonstrates the monophyly of Heteroponerinae with at least four synapomorphies supporting this hypothesis. The genera Acanthoponera and Heteroponera are also monophyletic in all topologies found here. The internal relationships indicate a basal position of the paleartic genus Aulacopone, which appears as sister group to the clade Acanthoponera + Heteroponera. Due to the lack of characters to provide robust support to the inclusion of Aulacopone within Heteroponerinae, this genus is considered as incertae sedis in the subfamily. The relative low resolution of the internal relationships in Acanthoponera and in the apical branches of Heteroponera does not prevent the recognition of evolutionarily independent lineages. The presence of these lineages in at least two biogeographic regions and the phylogenetic proximity found between Neotropical and Australian groups reveal an interesting biogeographic scenario to be investigated. After examining 33 out of the 36 type specimens designated for the species and subspecies of Heteroponerinae, six species are recognized in the genus Acanthoponera, two of which are here described as new. Heteroponera comprises 21 species, of which six are described as new; seven are restricted to the Australian Region (three newly described) and 14 are exclusively Neotropical (also three newly described). Heteroponera flava Kempf is synonymized under H. panamensis (Forel) and H. georgesi Perrault becomes a junior synonym of H. microps Borgmeier. Individuals yet not registered of castes and sexes (including males, gynes and workers) are here described for the first time for different species of Heteroponerinae. New records greatly expand the known distribution for most species. Field observations allied to label data from museum specimens provide important additional information about the natural history of the group. Larvae of Heteroponerinae are predominantly predators, and workers are occasionally observed feeding on plant exudates. Nests can support colonies with a some dozens to a few hundred of individuals. Heteroponera can nest in soil and vegetation, but preferably forage in the soil, while Acanthoponera is exclusively arboreal. With respect to the reproductive strategy, some species of Heteroponera may present ergatoid gynes sharing the reproductive function with dealate gynes, while in other species the winged gynes were completely replaced by ergatoids. As a next step to understand the evolutionary history of this group it is suggested an analysis of the internal relations within the heteroponerine genera using molecular tools and a study on the subfamily biogeographic patterns.
3
Giglio, Maria Cecilia Motta Torres. "O problema dos dois caminhos disjuntos." [s.n.], 1990. http://repositorio.unicamp.br/jspui/handle/REPOSIP/275866.
Full textAbstract:
Orientador: Claudio L. LucchesiDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Ciencia da Computação
Made available in DSpace on 2018-07-13T23:27:26Z (GMT). No. of bitstreams: 1 Giglio_MariaCeciliaMottaTorres_M.pdf: 5819263 bytes, checksum: c24dd7357f8a2283359356720f51597b (MD5) Previous issue date: 1990
Resumo: O problema dos dois caminhos disjuntos consiste em determinar, dados vértices s1, S2, t1 e t2 de um grafo, se existem ou não dois caminhos disjuntos, P1 e P2 ligando s1 a t1 e S1 a t1, respectivamente. O problema se manifesta em quatro versões, a saber, o grafo pode ser orientado ou não, e a exigência de disjunção pode ser apenas nas arestas ou também nos vértices. Nas quatro versões, o problema admite reduções elementares do ponto de vista computacional que levam finalmente à solução ou a uma certidão da sua não existência. Esta análise apresenta uma interconexão interessante entre combinatória, complexidade de algoritmos e topologia. No caso de grafos orientados, exige-se também que o grafo seja acíclico, pois caso contrário o problema se torna NP-difícil.
Abstract: The two disjoint paths problem consists in determining, given vertices S1, S2, t1 and t2 of a graph, whether or not there exist two disjoint paths. P1 and P21 joining s1 to t1 and S2 to t2 respectively. The problem may be considered in four versions, namely, the graph may or may not be directed, and the disjointness requirement on the paths may be on the edges only or on the vertices too. In all version, the problem admits computationally elementary reductions which provide either a solution or a certificate of its nonexistence. The analysis presents an interesting interconnection between combinatorics, complexity of algorithms and topology. In the case of direct graphs, it is also required that the graph be acyclic, otherwise the problem becomes NP-hard.
Mestrado
Mestre em Ciência da Computação
4
Gotch, Wendy Ellen. "The Behavior of the Horned Passalus Beetle, Odontotaenius disjunctus (Illiger)." W&M ScholarWorks, 1997. https://scholarworks.wm.edu/etd/1539626093.
Full text
5
Fang, Sarah (Mieko). "Disjuncted [electronic resourdce] :a collection of stories /." College Park, Md.: University of Maryland, 2009. http://hdl.handle.net/1903/9337.
Full textAbstract:
Thesis (M.F.A.) -- University of Maryland, College Park, 2009.Thesis research directed by: Dept. of English. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
6
Sabovljević, Marko. "Genetic distances and phylogeography of selected disjunct moss populations in Europe." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=980581338.
Full text
7
Silva, Pryscilla dos Santos Ferreira. "Códigos lineares disjuntos e corpos de funções algébricas." Universidade Federal da Paraíba, 2011. http://tede.biblioteca.ufpb.br:8080/handle/tede/7350.
Full textAbstract:
Made available in DSpace on 2015-05-15T11:45:58Z (GMT). No. of bitstreams: 1
arquivototal.pdf: 634504 bytes, checksum: ce035cc957832598c53dda96372e7cb7 (MD5)
Previous issue date: 2011-02-24Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
In this work, based on algebraic function fields, we give constructions of disjoint linear codes. In addition,we study the asymptotic behavior of disjoint linear codes from our constructions.
Neste trabalho, baseados em corpos de funções algébricas, forneceremos construções de códigos lineares disjuntos. Além disso, nós estudaremos comportamentos assintóticos de códigos lineares disjuntos a partir da nossa construção.
8
Boucher, Stéphanie 1974. "Diversity and zoogeography of Brachycera (Diptera) in disjunct grasslands of the southern Yukon." Thesis, McGill University, 1998. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=21515.
Full textAbstract:
The diversity and zoogeography of Diptera (Brachycera) of disjunct xeric grasslands in the southern Yukon were studied. Over 20,000 flies were collected representing 32 families and 213 species. In terms of abundance, the predacious guild dominated (54% of total specimens) due mostly to the family Chamaemyiidae which represented 45% of all specimens. In terms of diversity, the phytophagous and parasitoid guilds were dominant (25.5% of total species each). The most diverse families were Agromyzidae (32 species), Chloropidae (31 species), Tachinidae (23 species) and Pipunculidae (20 species). Thirty-four undescribed species were collected and 58 species were recorded for the first time in the Yukon. Zoogeographic analysis indicates that the Diptera fauna of these grasslands is dominated by widespread Nearctic or Holarctic species, but the fauna also includes southern grassland species with disjunct distributions, and species endemic to Beringia. The presence of endemic and disjunct species suggests that these grasslands were present in Beringia during the Wisconsinan and acted as a refugium for grassland Diptera.
9
Boucher, Stéphanie. "Diversity and zoogeography of Brachycera (Diptera) in disjunct grasslands of the southern Yukon." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ50724.pdf.
Full text
10
Johnson, Marie. "Demography and dendrochronology of a disjunct population of eastern hemlock in Southwestern Ohio." Wright State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=wright1535073403943795.
Full text
11
Barbieri, Caroline Domingues Porto do Nascimento. "Algoritmos para a síntese de circuitos reversíveis ternários : análise comparativa /." Ilha Solteira, 2018. http://hdl.handle.net/11449/157098.
Full textAbstract:
Orientador: Anna Diva Plasencia LotufoResumo: A lógica de múltiplos valores, em especial a ternária, apresenta inúmeras vantagens sobre a lógica binária em circuitos reversíveis/quânticos. A realização de funções usando a lógica reversível ternária é conhecida por requerer um menor número de linhas em comparação com a lógica reversível binária convencional. Este aspecto tem motivado as pesquisas em abordagens de síntese. A grande maioria dos métodos existentes requerem entradas adicionais, denominadas de ancillary lines, durante o processo de síntese, o que é dispendioso para implementação em tecnologias quânticas, quando disponíveis. Neste trabalho, foram propostas diferentes metodologias e análises comparativas para o problema da síntese de circuitos reversíveis ternários sem a adição de ancillary lines. A metodologia de síntese proposta, denominada de MMD plus, foi aplicado nos modos backward e top-down como referência a todas as 362880 possíveis funções reversíveis ternárias de 2 variáveis. Além do processamento top-down originário do algoritmo MMD, um processamento bottom-up é implementado e sua eficiência comparativa é avaliada. Por definição, as funções reversíveis ternárias são permutações. Realiza-se a decomposição das permutações em ciclos disjuntos de ordem natural, em ciclos de permutação com 3 elementos, e em transposições, para obtenção dos circuitos reversíveis ternários. Uma métrica é introduzida para mensurar a complexidade e custo dos circuitos, com base nas portas reversíveis de múltiplos valores Muthu... (Resumo completo, clicar acesso eletrônico abaixo)
Doutor
12
Rohrer, Wendy L. "A biosystematic study of the rare plant Paronychia virginica Sprengel (Caryophyllaceae) employing morphometric and allozyme analyses." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/46520.
Full textAbstract:
Paronychia virginica Spreng. (Caryophyllaceae) is a perennial evergreen herb of exposed, relatively xeric habitats. Approximately 10 mid-Appalachian populations remain in Virginia, West Virginia, and Maryland and are disjunct from populations located primarily in Texas, Oklahoma, and Arkansas. A study was conducted to test the hypothesis that eastern and western populations differ significantly and, therefore, represent at least two distinct taxa. Statistical analyses of 8 qualitative and 24 quantitative morphological characters indicated very highly significant (P < 0.001) variation between eastern and western populations of P. virginica. Characters differing most significantly included sepal pubescence, awn length, awn pubescence, awn curvature, length-width ratio of leaves, and shape of leaf apices. Starch gel electrophoresis was performed and six enzyme systems/nine loci (EST-2, EST-3, LAP, MDH-1, MDH-2, PGI, PGM-1, PGM-2, and SKDH) were identified as being consistently scorable and informative. Although gene flow between populations of P. virginica was shown to be restricted (mean FST = 0.353), populations are maintaining relatively high levels of genetic diversity. Genetic variability was quantified for each population and mean values for number of alleles per locus (A), percent loci polymorphic (P), and expected heterozygosity (HEXP) were found to be 1.95, 47.22%, and 0.204, respectively, exceeding those values reported for seed plants, widespread species, and endemic species. Hierarchical F statistics suggest higher levels of genetic variability within individual populations than among populations, regardless of geographic location. All statistically significant (P < 0.05) deviations from Hardy-Weinberg equilibrium indicated a deficiency in heterozygotes at the respective loci. Considering results from both the morphometric and allozyme analyses, the current author suggests recognizing two distinct subspecies, P. virginica subsp. virginica in the eastern U.S. and P. virginica subsp. scoparia in the south-central U.S. Conservation efforts should be focused on the maintenance of existing populations in both eastern and western regions of the U.S. in order to preserve the genetic and evolutionary potential of these taxa.Master of Science
13
Huang, Mingjuan. "Systematics of Trichostema L. (Lamiaceae) and phylogenetic relationships with its disjunct taxa in Asia." Connect to resource, 2002. http://rave.ohiolink.edu/etdc/view.cgi?acc%5Fnum=osu1261055296.
Full text
14
Ferreira, Marcos Rondiney dos Santos. "Comportamento assintótico de soluções da equação do aerofólio em intervalos disjuntos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/128043.
Full textAbstract:
Neste trabalho investigamos, dos pontos de vistas analítico e numérico, o comportamento assintótico da solução da equação do aerofólio, com uma singularidade do tipo Cauchy, de nida sobre um intervalo com uma pequena abertura. Exibimos um modelo matemático com uma solução f" para o intervalo disjunto G" = (−1,−ε) ∪ (ε, 1) e uma solução f0 que corresponde ao limite de f" quando (ε → 0), relacionando esta última com a solução da equação do aerofólio f no intervalo (−1, 1). Além do mais, demonstramos casos particulares de funções ψ = Tm e ψ = Un(onde Tm e Un são os polinômios de Tchebychev do primeiro e segundo tipo respectivamente) em que temos a igualdade f = f0 e conseqüentemente f" ≈ f. Apresentamos e comparamos numericamente as soluções f", f0 e f para diferentes funções ψ e valores de ε no intervalo G". Mostramos ainda soluções quase polinomiais analíticas da equação do aerofólio, e propomos um método espectral para a equação do aerofólio generalizada. Por m, obtemos soluções analíticas das equações do aerofólio para os intervalos G", (−1, 1)\ {0} e (−1, 1) para diferentes funções ψ(t) através da expansão em série da densidade da integral singular com núcleo Cauchy.In this work we investigate, of the analytical and numerical points of views, the asymptotic behavior of the airfoil equation solution with a singularity of the Cauchy type, de ned over a interval with a small opening. We display a mathematical model with a f" solution to the disjoint interval G" = (−1,−ε)∪(ε, 1) and a f0 solution corresponding to limit of f" when (ε → 0), linking the latter with the solution of the airfoil equation f in the interval (−1, 1). Furthermore, we demonstrate particular cases of functions ψ = Tm and ψ = Un (where Tm and Un are the Chebyshev polynomials of the rst and second type respectively) where we have equality f = f0 and then f" ≈ f. We present and compare numerically the solutions f", f0 and f for di erent functions ψ and values of ε in G". We also show almost polynomial analytical solutions for the airfoil equation, and we propose a spectral method for the generalized airfoil equation. Finally, we obtain analytical solutions of the airfoil equations to the interval G", (−1, 1)\ {0} and (−1, 1) for various functions ψ(t) by expanding in series the density of the Cauchy singular integral.
15
Uroz, Brosa Laia. "Freqüència i origen d'anomalies meiòtiques en individus fèrtils: Mecanismes de no disjunció." Doctoral thesis, Universitat Autònoma de Barcelona, 2009. http://hdl.handle.net/10803/3825.
Full textAbstract:
Les anomalies cromosòmiques a l'espècie humana són la causa principal de retard mental, retard del desenvolupament, infertilitat i esterilitat, afectant al voltant d'un 50% dels avortaments espontanis, un 6% de les morts perinatals i un 1% dels nounats. Un 86% d'aquestes anomalies s'originen durant la meiosi, però les seves freqüències i mecanismes d'origen han estat poc estudiats degut a la dificultat en l'obtenció del material d'estudi. La majoria d'estudis meiòtics s'han dut a terme en sèries d'individus infèrtils per diagnosticar l'etiologia de la seva infertilitat. Els objectius principals d'aquest treball són determinar la freqüència basal d'anomalies cromosòmiques meiòtiques en espermatòcits I de 17 individus fèrtils amb la tinció amb DAPI i descriure els mecanismes que les originen, especialment els mecanismes de no disjunció, aplicant la tècnica de FISH múltiplex (M-FISH) a espermatòcits I i II de tres d'aquests individus. A més, s'han analitzat els espermatòcits (M-FISH) i espermatozoides (FISH amb sondes) d'un individu amb infertilitat d'origen meiòtic per determinar l'origen de les seves anomalies meiòtiques. La freqüència total d'anomalies meiòtiques en espermatòcits I d'individus fèrtils era del 27%, sent les anomalies més comuns els errors sinàptics (23%), seguit de les anomalies estructurals (3%) i numèriques (1%). Els individus fèrtils són una població heterogènia respecte la freqüència d'anomalies meiòtiques, degut a la variabilitat interindividual en la freqüència de cromosomes sexuals dissociats. Els mecanismes que originen aneuploïdies a meiosi I són majoritàriament la no disjunció aquiasmàtica i la separació prematura de cromàtides germanes (PSSC). En aquest estudi s'han descrit per primera vegada a l'espermatogènesi humana la PSSC a meiosi I i la PSSC equilibrada a meiosi II. S'ha detectat un increment en la freqüència d'anomalies meiòtiques en individus fèrtils en relació amb les dades publicades en dècades anteriors, possiblement per l'aparició de nous factors de risc a la població.Chromosome abnormalities in humans are the leading cause of mental and physical disabilities, infertility and sterility, and they affect around 50% of spontaneous abortions, 6% of stillbirths and 1% of livebirths. Eighty-six percent of these abnormalities originate during meiosis but, to date, few studies have analyzed their frequencies and causal mechanisms due to the difficult access to the sample material. Most meiotic studies have been carried out in series of infertile patients to diagnose the aetiology of infertility. The main objectives of the present study are to determine the basal frequencies of meiotic chromosome abnormalities in spermatocytes from 17 fertile individuals with DAPI staining and to describe the causal mechanisms, especially nondisjunction mechanisms, by applying the multiplex FISH (M-FISH) technique to spermatocyte I and II from three of these individuals. Moreover, spermatocytes (M-FISH technique) and spermatozoa (FISH technique) from a patient with infertility were examined to determine the origin of his meiotic abnormalities. The overall frequency of meiotic abnormalities in spermatocytes I from fertile men was 27%, principally meiotic errors (23%), followed by structural (3%) and numerical abnormalities (1%). Fertile men are a heterogeneous population with regard to the frequency of meiotic abnormalities, due to interindividual variability in the frequency of dissociated sex chromosomes. The main mechanisms leading to aneuploidies in meiosis I are achiasmate nondisjunction and premature separation of sister chromatids (PSSC). The present study describes for the first time in human spermatogenesis both PSSC in meiosis I and balanced PSSC in meiosis II. We detected an increase in the frequencies of meiotic abnormalities in fertile men compared with the data published in the 1970s, probably caused by new risk factors in the population.
16
Meira, Vívian 1981. "A obviação/referência disjunta em complementação sentencial : uma proposta sintático-semântica." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/268917.
Full textAbstract:
Orientador: Sonia Maria Lazzarini CyrinoTese (doutorado) - Universidade Estadual de Campinas, Instituto de Estudos da Linguagem
Made available in DSpace on 2018-08-22T08:47:05Z (GMT). No. of bitstreams: 1 Meira_Vivian_D.pdf: 1178142 bytes, checksum: e326a7771cea8102eee5851541fef4ea (MD5) Previous issue date: 2013
Resumo: Esta tese investiga padrões de referencialidade em complementação sentencial no português, italiano e grego moderno, especialmente, o fenômeno conhecido como obviação ou referência disjunta. Esta é uma restrição atestada nas línguas e se caracteriza pelo fato de o sujeito da oração subordinada ser obrigatoriamente disjunto em referência ao sujeito da oração matriz. Tradicionalmente, assume-se que a obviação é uma propriedade de complementação subjuntiva ou um fenômeno resultante, juntamente com o controle, da competição entre formas finitas/não-finitas. No entanto, os dados não condizem com essas hipóteses, já que a obviação é exibida tanto em complementação indicativa quanto nos contextos de infinitivo flexionado. Além disso, nem todo contexto volitivo exibe obviação. Assumindo a teoria de seleção semântica e a versão minimalista de subcategorização (cf. Adger, 2004), propomos que a obviação, exibida em complementação sentencial, é uma restrição semântica exigida por três tipos de predicados, os causativos, os volitivos e os perceptivos físicos, que serão tomados como predicados modais no sentido de serem capazes de impor restrições semânticas aos seus complementos. Estes predicados foram denominados de predicados de obviação, por compartilharem entre si algumas propriedades, como denotar leitura eventiva/não-epistêmica, exigir sujeito pronominal na encaixada independente referencialmente do sujeito matriz e subcategorizar complemento TP. Argumentamos ainda que esses predicados, devido ao seu caráter modal, selecionam semanticamente um traço [obviativo], que é transmitido ao sujeito da encaixada. Predicados de obviação se distinguem de outro grupo de predicado modal, os predicados de controle, por estes não permitirem que o argumento da encaixada seja disjunto do sujeito matriz. Esses dois grupos se distinguem de outro grupo de verbos que permitem referência livre, constituído especialmente por predicados epistêmicos, declarativos, dentre outros, que denotam leitura epistêmica/proposicional e subcategorizam complemento CP. Sintaticamente este grupo de predicados se distingue dos predicados de obviação por subcategorizarem estruturas distintas, pois, enquanto estes têm complemento TP, aqueles selecionam complemento CP. Para explicar por que obviação e controle são exibidos pelo predicado volitivo, propomos que há dois tipos de acepções no volitivo nas línguas: o volitivo padrão, que seleciona controle e o volitivo causativo, que exige obviação. Defendemos que o complemento infinitivo flexionado selecionado por causativo e perceptivo é uma estrutura TP, o que o diferencia da estrutura de infinitivo flexionado selecionada por factivos/epistêmicos/declarativos, que é tomado como um CP. Estes permitem referência livre e aqueles exigem obviação. Nossa proposta é mostrar que a obviação, exibida em complementação sentencial, não é um fenômeno restrito às línguas românicas ou às línguas que exibem a distinção finito/não-finito, mas são uma restrição semântica imposta por predicados de obviação os seus complementos e, devido a isso, essa restrição semântica será exibida por línguas que dispõem desses contextos em complementação sentencial
Abstract: This thesis investigates patterns of referentiality in sentential complementation in Portuguese, Italian and Modern Greek, especially the phenomenon known as obviation or disjoint reference. This is a constraint attested in languages, and it is characterized by the fact that the subject of the subordinate clause must be disjoint in reference to the subject of the matrix sentence. Traditionally, obviation has been assumed to be a property of subjunctive complementation, or a phenomenon arising along with the control from the competition between finite/non-finite forms. However, the data are not consistent with these hypotheses, since obviation appears in indicative complementation and inflected infinitive contexts. Moreover, obviation is not displayed in every volitional context. Based on the theory of semantic selection and a minimalist version of subcategorization (cf. Adger, 2004), this thesis proposes that obviation, in sentential complementation, is a semantic constraint required by three types of predicates, the causative, volitional and physical perceptive predicates, which will be taken as predicates able to impose semantic constraints on their complements. These predicates are called obviation predicates, which share some common properties, as denoting eventive/non-epistemic reading, they require referentially independent subject pronouns in an embedded clause, and select a TP complement. We argue that these predicates, because of their modal character, select semantically a trace [obviative], which is transmitted to the subject in the embedded clause. Obviation predicates are distinguished from another group of modal predicates, control predicates, which do not allow, in an embedded clause, an argument referentially independent from the matrix subject. These two groups are distinguished from yet another group of verbs that allow free reference, specially constituted by epistemic, declarative predicates, among others, which denote an epistemic/propositional reading and select CP complements. Syntactically, this group can be distinguished from obviation predicates by selecting distinct structures, because while these have a TP complement, the former select CP complements. To explain why both obviation and control are displayed by volitional predicates, we propose that there are two types of volitional meanings in the languages: the default volitional that selects control, and the causative volitional, that requires obviation. Furthermore, we argue that the inflected infinitive complement selected by causative and perceptive verbs is a TP structure, and they require obviation, which differ from the inflected infinitive selected by factives/epistemic/declarative verb, which take CP complements and allows free reference. The purpose of this thesis is to show that obviation, in sentential complementation, is not a phenomenon restricted to the Romance languages, or languages that exhibit a distinction between finite and non-finite forms, but that it is a semantic constraint imposed by obviation predicates on their complements and, consequently, this constraint will appear in languages which have these contexts in sentential complementation
Doutorado
Linguistica
Doutora em Linguística
17
García-Cobián, Jáuregui Ramón. "Una revisión crítica de la Teoría de producción disjunta de Sraffa." Economía, 2012. http://repositorio.pucp.edu.pe/index/handle/123456789/116804.
Full textAbstract:
El propósito de este trabajo es el de proceder a una exhaustiva revisión de la teoría de producción disjunta de Sraffa. La justificación para una tal empresa la proporciona el comprobar que en [1], hay poca claridad en el lenguaje elegido, y poco rigor para demostrar las afirmaciones hechas. El Método elegido para este trabajo consiste en reformular, en un lenguaje matemático convencional, la teoría de Sraffa, para, a continuación, revisar la verdad o falsedad de las afirmaciones de dicha teoría.
18
Benevenuto, Juliana. "Evolução molecular do gene metionina sintase em populações disjuntas de Carapichea ipecacuanha (Rubiaceae)." Universidade Federal de Viçosa, 2013. http://locus.ufv.br/handle/123456789/4778.
Full textAbstract:
Made available in DSpace on 2015-03-26T13:42:28Z (GMT). No. of bitstreams: 1
texto completo.pdf: 2717003 bytes, checksum: 430ed9ce97311b4450b054a78245fcf2 (MD5)
Previous issue date: 2013-02-01Conselho Nacional de Desenvolvimento Científico e Tecnológico
Cobalamin-independent methionine synthase (MetE) is a key enzyme for de novo synthesis of methionine in plants and it is also responsible for the regeneration of S-adenosylmethionine, which is a metabolite associated with the process of interaction with pathogens, plant growth and stresses response. In this study, 95 complete sequences of the gene for methionine synthase were obtained from 26 specimens of Carapichea ipecacuanha (species of Rubiaceae family, which is popularly known as ipecac) with aims to understand and model evolutionary events that occurred on MetE locus and on the specimens from three disjuncts ranges of occurrence of this species (Atlantic, Amazon and Central America ranges). Sequences of ITS and 5.8S from nrDNA and trnT-trnL spacers from cpDNA were also used for a multiloci population analysis. The sequenced region of MetE covered 3,890pb, where 2,298pb correspond to the coding region (composed of 11 exons) and 1,592pb to the noncoding region (comprising 10 introns and a portion of 3'UTR). In the entire sample were obtained 75 haplotypes and a nucleotide diversity of 0.00899. FST and AMOVA analyzes of MetE indicated no structure in three regions, opposite to detected for other loci analyzed here and in previous studies in which high divergence among the specimens from three ranges was observed. However, in the network haplotype was possible to observe the sympatric distribution of the haplotypes. Possibly, excess of tip haplotypes and the small number of mutational steps among neighboring haplotypes from the three ranges do not allow that the differentiation among these was significant. The Bayesian phylogenetic tree rooted by Carapichea lucida (outgroup) using the coding region sequences showed the formation of clades by geographic regions and provided evidence that sequences from "Atlantic" range is closer to the ancestral state of the gene MetE than sequences from others ranges. The heterogeneity of results for neutrality tests and for values of haplotype and nucleotide diversity at different loci suggests that these are evolving independently and also suggests that demographic events do not explain the pattern found. Thereby, tests for the presence of selection site-by-site were performed for the coding region of the gene MetE and protein alignment against others MetE from diferents plant species available in the Genbank was develop too. Four sites under positive selection were found, but the results show that negative selection (purifying selection) is the main force acting on the locus, favoring the conservation of protein structure and function in all gene copies from C. ipecacuanha.
Metionina sintase independente de cobalamina (MetE) é uma enzima chave na via de síntese de novo de metionina em plantas e também é responsável pela regeneração de S-adenosilmetionina, metabólito associado à vias de interação com patógenos, crescimento vegetal e resposta à estresses. Neste estudo, 95 sequências do gene para metionina sintase foram obtidas a partir de 26 indivíduos de Carapichea ipecacuanha (espécie da família Rubiaceae, popularmente conhecida com ipeca) com objetivo de entender e modelar os eventos evolutivos que ocorreram sobre o locus MetE e sobre os indivíduos de três regiões disjuntas de ocorrência desta espécie (Mata Atlântica, Amazônia e América Central). Sequências de ITS do nrDNA e dos espaçadores trnT-trnL do cpDNA também foram utilizadas para uma análise populacional multiloci. A região sequenciada de MetE abrangeu 3.890pb, sendo 2.298pb correspondentes à região codificante (composta por 11 exons) e 1.592pb à região não codificante (composta por 10 introns e uma parte da região 3 UTR). No total, foram obtidos 75 haplótipos e uma diversidade nucleotídica de 0,00899. As análises FST e AMOVA de MetE indicaram ausência de estruturação em relação às três regiões, diferentemente do observado para os demais loci aqui analisados e em estudos prévios em que elevada divergência entre as três regiões foi observada. Por meio rede de haplótipos foi possível observar a distribuição simpátrica destes; no entanto, o excesso de haplótipos de ponta e o pequeno número de passos mutacionais entre haplótipos vizinhos das três regiões não permitem que a diferenciação destes seja significativa. A árvore filogenética Bayesiana enraizada por Carapichea lucida (grupo externo) utilizando a região codificante também mostrou a formação de clados por regiões geográficas e forneceu evidências de que sequências da Mata Atlântica sejam mais próximas do estado ancestral do gene MetE que as sequências das demais regiões. A heterogeneidade dos resultados encontrados para os testes de neutralidade e para os valores de diversidade nucleotídica e haplotípica nos diferentes loci sugerem que estes estão evoluindo independentemente e que eventos demográficos não explicam o padrão obtido. Assim, análises para a presença de seleção foram conduzidas para a região codificante do gene MetE e também foi realizado alinhamento de proteínas preditas para esta espécie contra proteínas MetE de outras espécies vegetais disponíveis no GenBank. Em quatro sítios houve evidência de seleção positiva, mas os resultados sugerem que a seleção negativa (purificadora) é a principal força atuando sobre o locus, favorecendo a conservação da estrutura e função proteica em todas as cópias gênicas de C. ipecacuanha.
19
ALMEIDA, T. B. "Estruturação Genética de Simothraulopsis diamantinensis Mariano, 2010. (EPHEMEROPTERA: LEPTOPHLEBIIDAE)." Universidade Federal do Espírito Santo, 2016. http://repositorio.ufes.br/handle/10/8273.
Full textAbstract:
Made available in DSpace on 2018-08-01T23:27:06Z (GMT). No. of bitstreams: 1
tese_10180_58 - Taís BArbosa Almeida20170912-84029.pdf: 1445488 bytes, checksum: 0959aab5d517a7b06d5ba312728c8906 (MD5)
Previous issue date: 2016-08-16Simothraulopsis Demoulin (1960) pertence à família Leptophlebiidae e é composto por nove espécies endêmicas da região Neotropical. Atualmente os registros de ocorrência de Simothraulopsis diamantinensis Mariano (2010) mostram uma distribuição disjunta, podendo ser encontrada no Estado do Espírito Santo, em Minas Gerais (na Serra do Cipó) e na Bahia (na Chapada Diamantina). Neste trabalho buscou-se obter os padrões da variação genética para S. diamantinensis e relacioná-los aos eventos passados em um contexto filogeográfico. Foram usadas sequências de duas regiões do gene mitocondrial: COI e COII de 57 e 61 indivíduos, respectivamente. Para isso foram conduzidas análises de diversidade genética, estruturação geográfica e história demográfica. Os resultados de diversidade genética e estrutura geográfica revelaram uma forte estruturação das populações de S. diamantinensis, que foram subdivididas em: (Vale do Capão + Serra do Cipó, Lençóis, Mucugê, Santa Teresa, Norte do Espírito Santo e Alegre), além disso os altos valores de Fst encontrados demonstraram que várias populações estão isoladas umas das outras e já não existe mais fluxo gênico entre elas. Os resultados de história demográfica sugerem que o padrão de diversificação encontrado para a espécie teve influência do Último Máximo Glacial, entretanto existe a possibilidade de ter ocorrido marcos que coincidam eventos geológicos e climáticos influenciando a diversificação, no mesmo tempo e espaço, que podem ter sido apagados por assinaturas genéticas mais recentes.
20
Batten, George Washington III. "Biogeography of the American Pika (Ochotona princeps) in Oregon and Southern Washington : illuminating genetic relationships among disjunct populations." PDXScholar, 2010. https://pdxscholar.library.pdx.edu/open_access_etds/3553.
Full textAbstract:
The American pika (Ochotona princeps) finds moderately warm temperatures (>25°C) lethally stressful, and at the end of the last Ice Age 10,000 years ago was forced to disperse to cooler, "sky island" mountaintops where they are almost exclusively found today. Thirty six subspecies are recognized, all established using morphological characters, and it is uncertain whether these subspecies' designations are corroborated by genetic analyses. This study elucidates three hypotheses regarding populations in Oregon and southern Washington: 1) O. p. fumosa constitutes a subspecies distinct form O. p. brunnescens, 2) the Columbia River constitutes a barrier to gene flow giving rise to two subspecies rather than the single subspecies O. p. brunnescens, and 3) populations in eastern Oregon ( O. p. jewetti and O. p. taylori) are genetically distinct from populations in the Cascade Range ( 0. p. brunnescens and O. p. fumosa).
21
Guíñez, Abarzúa Flavio Ricardo. "Realizaciones disjuntas de secuencias de grado en grafos con algunas aplicaciones a tomografía discreta." Tesis, Universidad de Chile, 2009. http://www.repositorio.uchile.cl/handle/2250/102131.
Full textAbstract:
Esta tesis trata sobre un problema de reconstrucción en Tomografía Discreta en el cual se está interesado en colorear una grilla usando k colores, de tal forma que para cada fila y columna, el número de celdas de cada color sea un cierto valor previamente dado. Para k = 2, un resultado clásico de la Combinatoria entrega una condición necesaria y suficiente para la existencia de tal coloración junto con un algoritmo polinomial para construirla cuando existe. Por otro lado, Chrobak y Dürr mostraron que para k mayor o igual a 4 el problema es NP-difícil.
La equivalencia natural entre una grilla y un grafo bipartito completo muestra que el caso k=3 corresponde a la restricción a esta clase de grafos del siguiente problema:
Dados un grafo G y funciones enteras b¹ y b² en V(G), ¿existen b¹ y b²-factores de G que sean disjuntos?
En esta tesis introducimos una nueva condición para este problema, la que resulta ser suficiente cuando G es un grafo bipartito completo y la diferencia entre el máximo y mínimo valor de b¹ + b² es a los más dos. La demostración de este resultado se basa en un algoritmo polinomial que encuentra dos factores disjuntos o bien un certificado de inexistencia.
Junto con esto, la contribución principal de esta tesis es la prueba de NP-dificultad del problema para grafos bipartitos completos cuando no se impone ninguna condición a b¹ y b². Esto resuelve el caso k = 3 del mencionado problema en Tomografía Discreta, lo que cierra el problema para todos los valores de k. Como corolario obtenemos además que el problema para grafos completos es también NP-difícil.
Para el problema de unicidad, caracterizamos las transformaciones que preservan las funciones b¹ y b² cuando G es un grafo bipartito. Este resultado es luego utilizado para probar la existencia de invariantes para algunas 3-coloraciones de la grilla.
Además, estudiamos la generalización del problema de k-coloración a la reconstrucción de embaldosados de la grilla usando como baldosas k rectángulos de diferentes tamaños. Para este problema, presentamos demostraciones que abarcan y extienden todos los resultados previos conocidos.
Para finalizar, se prueba la existencia de un núcleo cuadrático para una generalización del problema de Vertex Cover parametrizado por el tamaño requerido del conjunto solución.
22
Cambaliza, Maria Obiminda L. "Measurement of forest ecosystem-atmosphere exchange of 8¹³C-CO₂ using Fourier transform infrared spectroscopy and disjunct eddy covariance." Pullman, Wash. : Washington State University, 2010. http://www.dissertations.wsu.edu/Dissertations/Spring2010/m_cambaliza_121709.pdf.
Full textAbstract:
Thesis (Ph. D.)--Washington State University, May 2010.Title from PDF title page (viewed on June 10, 2010). "Department of Civil and Environmental Engineering." Includes bibliographical references.
23
Queiroz, Ricardo Alexandro de Andrade. "Eliciação e comunicação de requisitos em domínios disjuntos: estudo de caso para a área médica." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/3/3152/tde-23072007-232758/.
Full textAbstract:
A Engenharia de Requisitos (ER) vem sendo reconhecida como uma área de pesquisa de extrema relevância para o desenvolvimento de sistemas ou artefatos. As maiores causas de falhas ocorridas em projetos são oriundas do processo de aquisição e tradução dos objetivos, necessidades ou restrições estabelecidas pelos clientes e/ou usuários. Estes erros podem aumentar de forma exponencial em projetos que se propõem a desenvolver sistemas ou artefatos que estejam diretamente associados à área cirúrgica, devido a diferença do domínio de conhecimento e o vocabulário entre as mencionadas áreas. Desta forma, verifica-se a importância científica para desenvolver modelos ou métodos que minimizem o problema apresentado. Ajudar na análise e definição, de maneira apurada e precisa, junto ao especialista da área médica, em relação aos movimentos executados em um procedimento minimamente invasivo e auxiliar a área de projetos de engenharia a desenvolver esse tipo de sistema. Este trabalho de dissertação apresenta o desenvolvimento de um modelo de conduta para o processo de eliciação e comunicação de requisitos no cenário em que o desenvolvedor e o especialista pertencem a diferentes domínios, técnicas e linguagens próprias. É também realizada a aplicação prática do modelo, em uma cirurgia minimamente invasiva, em específico à cirurgia da catarata. A aplicação prática foi realizada com o total apoio do Hospital Santa Luzia e do Instituto da Catarata, UNIFESP.In recent years, the requirements engineering process has become known as a research with extreme relevance for system development. The major failures in projects are caused by the translation requirements, i.e. the task of communicating with customers and users to determine what their requirements are. These mistakes can rise exponentially in system development projects that are directly associated with the area of surgery, because of the difference of knowledge domain and the vocabulary between the mentioned areas (engineering and medicine). In this way rises the scientific importance for models development or methods that minimize the problem presented above. Helping analyzing and defining, in a fine and accurate way, a long with a specialist from the medical area, relating the movements executed in the minimally invasive process and help the area of engineering design develop this type of system. Considering this, we propose in this dissertation the development of a model that show elicitation process and a communication of requirements in a scenario in which the developer and stackholder pretence a different types of domain, techniques and proper languages. The model is also practices in a minimally invasive surgery, especially in cataract surgery. It was practiced with the full support of Santa Luzia Hospital, and the Institute of Cataract, UNIFESP.
24
GIROLIMETTO, M. "Explorando a Diversidade de Pares de Caminhos Disjuntos por Arestas em Redes Ópticas Elásticas Sobreviventes." Universidade Federal do Espírito Santo, 2018. http://repositorio.ufes.br/handle/10/9582.
Full textAbstract:
Made available in DSpace on 2018-08-02T00:00:47Z (GMT). No. of bitstreams: 1
tese_12072_Marina_Girolimetto_Dissertacao_Mestrado.pdf: 1922035 bytes, checksum: 2f58d338f19992ed7fac226685f59464 (MD5)
Previous issue date: 2018-04-26tba
25
McDonald, Leah E. "Plant Species of the Virginia Coastal Plain Flora that Are Disjunct from the Mountains: their Distribution, Abundance and Substrate Selectivity." W&M ScholarWorks, 2000. https://scholarworks.wm.edu/etd/1539626249.
Full text
26
Lira, Dayane Santos de. "Sobre o número máximo de retas duas a duas disjuntas em superfícies não singulares em P3." Universidade Federal da Paraíba, 2017. http://tede.biblioteca.ufpb.br:8080/handle/tede/9294.
Full textAbstract:
Submitted by ANA KARLA PEREIRA RODRIGUES (anakarla_@hotmail.com) on 2017-08-22T13:57:08Z
No. of bitstreams: 1
arquivototal.pdf: 1762696 bytes, checksum: 53bf47b7590ebc1271d2f0d81822f00c (MD5)Made available in DSpace on 2017-08-22T13:57:08Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1762696 bytes, checksum: 53bf47b7590ebc1271d2f0d81822f00c (MD5) Previous issue date: 2017-02-24
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
This work aims to determine the maximum number of pairwise disjoint lines that a non-singular surface of degree d in P3 can contain. In the case of degrees d = 1 and d = 2 we found that these values are zero and in nite, respectively. Furthermore, in the case of degree d = 3 we did show that the maximum number of pairwise disjoint lines is 6, these con gurations were studied in 1863 by the Swiss Ludwig Schl a i (1814-1895) in [15]. For the case d = 4, in 1975 the Russian Viacheslav Nikulin in [10] showed that non-singular quartic surfaces contain at most 16 pairwise disjoint lines. In our work, we have been able to show that Schur's famous quartic achieves this bound and that Fermat's quartic has at most 12 pairwise disjoint lines. We also determined lower bounds for the maximum number of pairwise disjoint lines in the case of non-singular surfaces of degree d 5. For example, the Rams's family in [11] allows us to nd one of these lower bounds.
Este trabalho objetiva determinar a quantidade máxima de retas duas a duas disjuntas que uma superfície não singular de grau d em P3 pode conter. No caso dos graus d = 1 e d = 2 verificamos que estes valores s~ao zero e in nito, respectivamente. Al em disso, no caso de grau d = 3 mostramos que o n umero m aximo de retas duas a duas disjuntas e 6, ditas con gura c~oes foram estudadas em 1863 pelo sui co Ludwig Schl a i (1814-1895) em [15]. Para o caso d = 4, em 1975 o russo Viacheslav Nikulin em [10] mostrou que as superf cies qu articas n~ao singulares cont^em no m aximo 16 retas duas a duas disjuntas. No nosso trabalho, conseguimos mostrar que a famosa qu artica de Schur atinge essa cota e que qu artica de Fermat possui no m aximo 12 retas duas a duas disjuntas. Determinamos ainda cotas inferiores para o n umero m aximo de retas duas a duas disjuntas no caso de superf cies n~ao singulares de grau d 5. Por exemplo, a fam lia de Rams em [11] nos permite achar uma dessas cotas inferiores.
27
Scot, Sky. "An Investigation Concerning the Base-Generation of Four Old English Conjunct and Disjunct Adverbials within the Structure of Old English Clauses." Thesis, Stockholm University, Stockholm University, Stockholm University, Stockholm University, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-27928.
Full textAbstract:
This paper is concerned with an investigation of four Old English adverbials with respect to where they are base-generated within the substructure of clauses which serve as examples of Old English prose. There are three structures in which base-generation of clausal constituents is deemed to occur: the CP, the IP, and the VP. Function and derivational movement are the governing factors which regulate the possibility of base-generation occurring within a particular structure. The movements undergone by clausal constituents, from their places of origin within the ‘underlying structures’ to their syntactic realization in the ‘surface structures’ of Old English clauses, are founded upon the model outlined in Johannesson (2009a) which is based on the tenets of Government and Binding theory. As there are no native speakers of Old English, the functions of these adverbials within their clausal environments are determined by their Modern English interpretations. Due to time and space constraints, four Old English adverbials were analysed within the context of one-hundred and twenty clauses which were extracted from The Dictionary of Old English Corpus (2004). Cases deemed to be ambiguous are addressed and classified separately; only one such case was encountered in the course of this study.
The results should exhibit proof that base-generation of the four Old English conjunct and disjunct adverbials investigated occurs within one of the aforementioned structures. Note that any conclusions drawn are based upon Modern English translations and that the results pertain to the genre of Old English prose.
28
Langford, Ben. "Development and application of disjunct eddy covariance techniques for hte measurement and interpretation of fluxes of volatile organic compontds from urban and rural canopies." Thesis, Lancaster University, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.525301.
Full text
29
Ribeiro, Leandro Carvalho. "Fatores ambientais e a germinação de espécies arbóreas do Brasil Central e de áreas disjuntas da Amazônia no bioma Cerrado." reponame:Repositório Institucional da UnB, 2014. http://repositorio.unb.br/handle/10482/18916.
Full textAbstract:
Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Botânica, Programa de Pós-graduação em Botânica, 2014.Submitted by Fernanda Percia França (fernandafranca@bce.unb.br) on 2015-12-10T18:26:20Z No. of bitstreams: 1 2014_LeandroCarvalhoRibeiro.pdf: 2762943 bytes, checksum: 4c8f24747b8e4ac02ff26e5b41dbe4dd (MD5)
Approved for entry into archive by Raquel Viana(raquelviana@bce.unb.br) on 2015-12-15T16:09:27Z (GMT) No. of bitstreams: 1 2014_LeandroCarvalhoRibeiro.pdf: 2762943 bytes, checksum: 4c8f24747b8e4ac02ff26e5b41dbe4dd (MD5)
Made available in DSpace on 2015-12-15T16:09:27Z (GMT). No. of bitstreams: 1 2014_LeandroCarvalhoRibeiro.pdf: 2762943 bytes, checksum: 4c8f24747b8e4ac02ff26e5b41dbe4dd (MD5)
O Cerrado é o segundo maior bioma do Brasil e sua área nuclear ocorre no Planalto Central. Este bioma também ocorre em áreas disjuntas na região Norte do país, as quais são denominadas savanas amazônicas, destacando-se aquelas do estado de Roraima, que ocupam as maiores áreas de cerrado na Amazônia brasileira. Devido à ampla ocorrência geográfica do Cerrado, sua vegetação está exposta a diferentes gradientes de condições ambientais, e fatores como amplitude térmica elevada, déficit hídrico sazonal e ocorrência de fogo têm sido considerados os principais filtros ambientais que determinam a composição de espécies no bioma. Entretanto, os efeitos desses filtros sobre a capacidade de recrutamento, a partir de sementes, continuam pouco compreendidos. Em função das diferenças ambientais locais existentes entre os cerrados de Roraima e os do Planalto Central brasileiro, que sinalizam para uma maior tolerância a estresses ambientais para espécies de Roraima, o objetivo deste estudo foi investigar como a umidade reduzida, o déficit hídrico, choques térmicos e altas temperaturas afetam a estratégia de germinação de sementes de três espécies arbóreas (Bowdichia virgilioides, Curatella americana e Anadenanthera peregrina) que ocorrem em ambos os locais. De modo geral, sementes das populações ocorrentes nos cerrados de Roraima apresentaram maior tolerância à dessecação, ao déficit hídrico e aos choques térmicos do que sementes das populações dos cerrados do Brasil Central. Além disso, sementes das populações de Roraima também germinaram em faixa de temperatura mais ampla que aquelas do Brasil Central. Os tratamentos de choques térmicos e dessecação não alteraram de maneira significativa a velocidade de germinação de nenhuma espécie, independente do ambiente de origem da população. Por outro lado, o déficit hídrico crescente tornou a germinação das espécies significativamente mais lenta, independente do ambiente de origem da população. Modelos relacionados a mudanças climáticas prevêem a intensificação nos níveis de alguns estresses ambientais (aumento no déficit hídrico do solo, maiores temperaturas máximas e aumento na frequência de fogo) em diversas regiões onde o bioma Cerrado ocorre, os quais podem influenciar diretamente o processo germinativo. Considerando tais aspectos e de acordo com os resultados descritos para as três espécies deste estudo, mudanças ambientais serão, possivelmente, mais limitantes ao recrutamento de espécies, por sementes, às populações dos cerrados do Brasil Central. ______________________________________________________________________________________________ ABSTRACT
The Cerrado is the second largest Brazilian biome and its core area occurs in the Central Plateau. This biome also occurs in disjunct areas in the Northern region, which are named Amazonian savannas. In Roraima state are found the largest savanna areas of the Brazilian Amazon. Due to its wide geographical distribution in the Brazilian territory, the Cerrado occurs across a wide range of environmental conditions, and factors such as high temperatures, seasonal drought and fire have been considered filters determining species composition in the biome. However, the effects of these filters on the recruitment capability, from seeds, remain poorly understood. Due to the local environmental differences among Brazilian Central Plateau and Roraima cerrados, which point to a greater tolerance to environmental stress for Roraima species, the aim of this study was to investigate how the low moisture, drought, heat shocks and high temperatures affect the germination parameters of three woody species (Bowdichia virgilioides, Curatella americana e Anadenanthera peregrina) from both sites. Overall, seeds occurring in the Roraima populations showed higher tolerance to desiccation, drought and heat shocks than seeds occurring in the Brazilian Central Plateau. Furthermore, Roraima species also germinated in a wider temperature range. Heat shocks and desiccation did not consistently change germination rate for none species of this study, regardless of the population origin. On the other hand, increasing drought made seed germination consistently slower, for both Roraima and Centrau Plateau populations. Climate change models predict increases for some environmental stress (soil moisture redution, higher maximum temperatures and fire frequencies) within the geographical area of the Cerrado biome, which may have a direct effect on the seed germination. Considering these aspects and also according to the results presented for the three species of this study, environmental changes will be more limiting to the plant recruitment, from seeds, for Central Plateau populations.
30
Borges, Junior Sergio Ricardo. "SEnsembles – uma abordagem para melhorar a qualidade das correspondências de instâncias disjuntas em estudos observacionais explorando características idênticas e ensembles de regressores." Universidade Federal de São Carlos, 2016. https://repositorio.ufscar.br/handle/ufscar/8911.
Full textAbstract:
Submitted by Ronildo Prado (ronisp@ufscar.br) on 2017-07-19T10:44:04Z
No. of bitstreams: 1
TeseSRBJ.pdf: 5473127 bytes, checksum: 6ad9d0f7d24cadafbff18e445b8736d1 (MD5)Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-07-19T10:44:16Z (GMT) No. of bitstreams: 1 TeseSRBJ.pdf: 5473127 bytes, checksum: 6ad9d0f7d24cadafbff18e445b8736d1 (MD5)
Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-07-19T10:44:27Z (GMT) No. of bitstreams: 1 TeseSRBJ.pdf: 5473127 bytes, checksum: 6ad9d0f7d24cadafbff18e445b8736d1 (MD5)
Made available in DSpace on 2017-07-19T10:45:12Z (GMT). No. of bitstreams: 1 TeseSRBJ.pdf: 5473127 bytes, checksum: 6ad9d0f7d24cadafbff18e445b8736d1 (MD5) Previous issue date: 2016-12-16
Não recebi financiamento
Introduction. The datasets used in observational studies have instances belonging to two distinct groups (i.e. treatment group and control group), which are compared in order to estimate the effect of the treatment over the results. For such, in one of the approaches, called Propensity Score Matching (PSM), the propensity score for the instances of both groups is estimated and, subsequently, the correspondence of these instances is performed based on the values for the propensity score. The propensity score is the probability of attribution of a treatment based on the observed characteristics (e.g. income, sex and age). In this context, the logistic regression is widely used to estimate the propensity score and there is an great variety of instance correspondence methods. Objective. This doctor´s thesis has as its main objective to investigate computational alternatives in order to improve the quality of the instance correspondence in datasets that are manipulated in observational studies. Methodology. Techniques that estimate the propensity score and methods to perform the instance correspondence in observational studies were investigated. Thus, it was possible to investigate how the identical characteristics of the instances could be exploited in a new process to perform correspondence and, how ensembles could substitute the logistic regression by estimating the propensity scores of the instances, in the context of the PSM process. Proposal. This thesis proposes a new approach in the context of the PSM process, called “SEnsembles”, which aims to improve the quality of instance correspondence based on two main processes, which use techniques that separately consider the identical characteristics of the instances and the ensembles of regressors, more precisely, bagging, random forest and boosting. Results. The proposed approach “SEnsembles” improves the quality of the instance correspondence for the majority of calipers used (i.e. zero, 0.05, 0.10, 0.15, 0.20, 0.25 and 0.30) when compared to the baseline Nearest Neighbor Matching (NNM). Based on the experiments, when there was an improvement over the baseline, the technique that separates the identical characteristics of the instances presented improvements of up to 53.8% in the quality of correspondence, with an average of gains of 12.1%; and only 2.7% of average in the reduction of the number of pairs of instances matched. The technique which substituted the logistic regression for ensembles of regressors, in turn, presented the best correspondence with the caliper zero and with the values 0.20, 0.25 and 0.30, with improvements of up to 36.3% and an average of gains of 12.7%; and a slightly reduction of 7.6% in the number of pairs of instances matched.
Introdução. Os conjuntos de dados manipulados em estudos observacionais possuem instâncias pertencentes a dois grupos distintos (i.e. grupo de tratamento e grupo de controle), as quais são comparadas para estimar o efeito do tratamento sobre os resultados. Para isso, em uma das abordagens, chamada de Propensity Score Matching (PSM), estima-se o escore de propensão para as instâncias de ambos os grupos e, em seguida, efetua-se a correspondência dessas instâncias com base nos valores dos escores de propensão. O escore de propensão é a probabilidade de atribuição de um tratamento com base nas características observadas (por exemplo, renda, sexo e idade). Neste contexto, a regressão logística é amplamente utilizada para estimar o escore de propensão e há uma ampla variedade de métodos de correspondência de instâncias. Objetivo. Esta pesquisa de doutorado tem como objetivo principal investigar alternativas computacionais para melhorar a qualidade das correspondências de instâncias em conjuntos de dados que são manipulados em estudos observacionais. Metodologia. Investigou-se técnicas que estimam o escore de propensão e métodos para se efetuar a correspondência das instâncias em estudos observacionais. Assim, foi possível investigar como as características idênticas das instâncias poderiam ser exploradas em um novo processo de correspondência e, como ensembles, mais precisamente, bagging, random forest e boosting, poderiam substituir a regressão logística ao estimar os escores de propensão das instâncias, no contexto do processo de PSM. Proposta. Esta pesquisa propõe uma nova abordagem no contexto do processo PSM, denominada “SEnsembles”, que visa melhorar a qualidade da correspondência das instâncias com base em 2 processos principais, os quais utilizam técnicas que considerem em separado as características idênticas das instâncias e os ensembles de regressores, mais precisamente, bagging, random forest e boosting. Resultados. A abordagem proposta “SEnsembles” melhorou a qualidade da correspondência de instâncias para a maioria dos calipers utilizado (zero, 0,05, 0,10, 0,15, 0,20, 0,25 e 0,30) quando comparada ao baseline Nearest Neighbor Matching (NNM). Com base nos experimentos, quando houve ganho, a técnica que separa as características idênticas das instâncias proporcionou ganhos de até 53,8% na qualidade da correspondência, com média de 12,1% de melhoria e 2,7% de redução média do número de pares de instâncias correspondidas. Já a técnica que substituiu a regressão logística pelos ensembles proporcionou as melhores correspondências com o caliper zero e com os valores 0,20, 0,25 e 0,30, com ganhos de até 36,3% e, com média de 12,7% de melhoria e 7,6% de redução do número de pares de instâncias correspondidas.
31
VASCONCELOS, José Eder Salvador de. "A Propriedade Erdös-Pósa para matróides." Universidade Federal de Campina Grande, 2009. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/1217.
Full textAbstract:
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-07-23T15:16:49Z
No. of bitstreams: 1
JOSÉ EDER SALVADOR DE VASCONCELOS - DISSERTAÇÃO PPGMAT 2009..pdf: 634118 bytes, checksum: e65e70c702364b197a36f09e8d1ef296 (MD5)Made available in DSpace on 2018-07-23T15:16:49Z (GMT). No. of bitstreams: 1 JOSÉ EDER SALVADOR DE VASCONCELOS - DISSERTAÇÃO PPGMAT 2009..pdf: 634118 bytes, checksum: e65e70c702364b197a36f09e8d1ef296 (MD5) Previous issue date: 2009-11
Capes
O número de cocircuitos disjuntos em uma matróide é delimitado pelo seu posto. Existem, no entanto, matróides de posto arbitrariamente grande que não contêm dois cocircuitos disjuntos. Considere, por exemplo,M(Kn) eUn,2n. Além disso, a matróide bicircularB(Kn) pode ter posto arbitrariamente grande, mas não tem 3 cocircuitos disjuntos. Nós apresentaremos uma prova, obtida por Jim Geelen e Kasper Kabell em (5), para o seguinte fato: para cadak en, existe uma constantec tal que, seM é uma matróide com posto no mínimoc, entãoM temk cocircuitos disjuntos ou contém uma das seguintes matróides como menorUn,2n,M(Kn) ouB(Kn).
The number of disjoint cocircuits in a matroid is bounded by its rank. There are, however, matroids of rank arbitrarily large that do not contain two disjoint cocircuits. Consider, for example,M(kn) andUn,2n. Moreover, the bicircular matroidB(kn) may have arbitrarily large rank but do not have 3 disjoints cocircuits. We show a proof obtained by Jim Geelen and Kasper Kabell in (5) to the following fact: for everyk andn, there is a constantc such that ifM is a matroid with rank at leastc, thenM hask disjoint cocircuits orM contains one of the following matroids as a minorUn,2n, M(kn) orB(kn).
32
Baghi, Romain. "Emissions biogéniques de composés organiques volatils en région méditerranéenne - développement instrumental, mesures et modélisation." Phd thesis, Université Paul Sabatier - Toulouse III, 2013. http://tel.archives-ouvertes.fr/tel-00873143.
Full textAbstract:
Les Composés Organiques Volatils (COV) jouent un rôle important dans la chimie de l'atmosphère et participent à la formation de polluants secondaires comme l'ozone et les aérosols organiques. Les émissions biogéniques de COV dominent d'un facteur dix les émissions anthropiques à l'échelle globale mais leur caractérisation à l'échelle régionale est incertaine. Les progrès en modélisation de la chimie atmosphérique passent par l'amélioration des inventaires d'émissions, ce qui nécessite des mesures de flux in situ. Ces travaux portent sur l'étude des émissions de COV biogéniques par les végétations méditerranéennes dans le cadre du programme ChArMEx (Chemistry and Aerosol Mediterranean Experiment) qui vise à concentrer les efforts scientifiques sur l'étude de la chimie et des aérosols de l'atmosphère du bassin méditerranéen. La méthode Eddy Covariance (EC) permet de quantifier directement les échanges d'espèces chimiques entre la surface et l'atmosphère. Cette méthode constitue une référence pour les mesures de flux mais n'est applicable qu'à un nombre limité d'espèces car elle requiert la mesure rapide (~ 0,1 s) et simultanée de la concentration du composé étudié ainsi que de la vitesse du vent vertical. Afin d'élargir le champ de mise en œuvre de cette technique d'autres solutions dérivées de l'EC ont été proposées, dont la méthode Disjunct Eddy Covariance (DEC) qui a pour particularité de réduire la contrainte sur la mesure rapide de l'espèce chimique tout en gardant une précision acceptable sur le calcul du flux. Dans le cadre de ces travaux de thèse un système de prélèvement a été développé pour mettre en œuvre la mesure de flux de COV par la méthode DEC. Ce dispositif appelé MEDEE (Mesures par Échantillonnage Disjoint des Échanges d'Espèces en trace) repose sur une technologie nouvelle qui permet une capture rapide d'un échantillon d'air et assure son transfert à pression constante vers un analyseur connecté en ligne. Il est composé de deux "seringues mécaniques" actionnées par des vérins électriques dont le fonctionnement est alterné pour alimenter en continu l'analyseur. Trois électrovannes disposées à l'entrée de chaque réservoir dirigent le flux d'air en fonction du cycle de fonctionnement. L'ensemble du système est cadencé par un microcontrôleur avec une précision à la milliseconde. Le système de prélèvement a été réalisé en matériaux inertes chimiquement pour éviter la dégradation de l'échantillon et être compatible avec les espèces en trace réactives. MEDEE a été testé et validé pour les mesures de flux au sol et en avion lors de deux campagnes de terrain. Le système MEDEE a ainsi permis, lors de deux campagnes de mesures pendant les étés 2010 et 2011 au-dessus d'une forêt de chênes pubescents, de mesurer les flux d'isoprène grâce à un couplage avec un analyseur adapté (Fast Isoprene Sensor). Un réseau de neurones artificiels (RNA) a ensuite été utilisé pour déterminer une paramétrisation des flux d'isoprène en fonction des paramètres environnementaux à partir des observations des campagnes de mesures. La modélisation des émissions d'isoprène a été validée pour les conditions environnementales rencontrées. Cette paramétrisation servira dans un modèle de chimie atmosphérique à l'étude de l'impact des émissions de COV biogéniques sur la qualité de l'air.
33
Baghi, Romain. "Émissions biogéniques de composés organiques volatils en région méditerranéenne : développement instrumental, mesures et modélisation." Toulouse 3, 2013. http://thesesups.ups-tlse.fr/2248/.
Full textAbstract:
Les Composés Organiques Volatils (COV) jouent un rôle important dans la chimie de l'atmosphère et participent à la formation de polluants secondaires comme l'ozone et les aérosols organiques. Les émissions biogéniques de COV dominent d'un facteur dix les émissions anthropiques à l'échelle globale mais leur caractérisation à l'échelle régionale est incertaine. Les progrès en modélisation de la chimie atmosphérique passent par l'amélioration des inventaires d'émissions, ce qui nécessite des mesures de flux in situ. Ces travaux portent sur l'étude des émissions de COV biogéniques par les végétations méditerranéennes dans le cadre du programme ChArMEx (Chemistry and Aerosol Mediterranean Experiment) qui vise à concentrer les efforts scientifiques sur l'étude de la chimie et des aérosols de l'atmosphère du bassin méditerranéen. La méthode Eddy Covariance (EC) permet de quantifier directement les échanges d'espèces chimiques entre la surface et l'atmosphère. Cette méthode constitue une référence pour les mesures de flux mais n'est applicable qu'à un nombre limité d'espèces car elle requiert la mesure rapide (~ 0,1 s) et simultanée de la concentration du composé étudié ainsi que de la vitesse du vent vertical. Afin d'élargir le champ de mise en œuvre de cette technique d'autres solutions dérivées de l'EC ont été proposées, dont la méthode Disjunct Eddy Covariance (DEC) qui a pour particularité de réduire la contrainte sur la mesure rapide de l'espèce chimique tout en gardant une précision acceptable sur le calcul du flux. Dans le cadre de ces travaux de thèse un système de prélèvement a été développé pour mettre en œuvre la mesure de flux de COV par la méthode DEC. Ce dispositif appelé MEDEE (Mesures par Échantillonnage Disjoint des Échanges d'Espèces en trace) repose sur une technologie nouvelle qui permet une capture rapide d'un échantillon d'air et assure son transfert à pression constante vers un analyseur connecté en ligne. Il est composé de deux "seringues mécaniques" actionnées par des vérins électriques dont le fonctionnement est alterné pour alimenter en continu l'analyseur. Trois électrovannes disposées à l'entrée de chaque réservoir dirigent le flux d'air en fonction du cycle de fonctionnement. L'ensemble du système est cadencé par un microcontrôleur avec une précision à la milliseconde. Le système de prélèvement a été réalisé en matériaux inertes chimiquement pour éviter la dégradation de l'échantillon et être compatible avec les espèces en trace réactives. MEDEE a été testé et validé pour les mesures de flux au sol et en avion lors de deux campagnes de terrain. Le système MEDEE a ainsi permis, lors de deux campagnes de mesures pendant les étés 2010 et 2011 au-dessus d'une forêt de chênes pubescents, de mesurer les flux d'isoprène grâce à un couplage avec un analyseur adapté (Fast Isoprene Sensor). Un réseau de neurones artificiels (RNA) a ensuite été utilisé pour déterminer une paramétrisation des flux d'isoprène en fonction des paramètres environnementaux à partir des observations des campagnes de mesures. La modélisation des émissions d'isoprène a été validée pour les conditions environnementales rencontrées. Cette paramétrisation servira dans un modèle de chimie atmosphérique à l'étude de l'impact des émissions de COV biogéniques sur la qualité de l'airVolatile Organic Compounds (VOC) play an important role in atmospheric chemistry and are involved in the formation of secondary atmospheric pollutants as ozone and organic aerosols. Biogenic emissions of volatile organic compounds are tenfold greater than anthropogenic emissions on a global scale but their characterization remains uncertain regionally. Advances in atmospheric chemistry modeling rely on better emission inventory which needs in situ flux measurement. This work focuses on biogenic VOC emissions from Mediterranean vegetation in the frame of ChArMEx (Chemistry and Aerosol Mediterranean Experiment) that aims to concentrate scientific effort to study atmospheric chemistry and aerosols in the Mediterranean region. The Eddy Covariance (EC) method allows direct measurement of trace gas exchange between the surface and the atmosphere. EC is a reference method for flux measurement but is adapted to only a limited number of trace gas species because it requires simultaneous fast measurement (~ 0. 1 s) of the species concentration and vertical wind speed. In order to broaden the range of applicability of this method, several other methods derived from EC have been proposed. Among these, the Disjunct Eddy Covariance (DEC) method relaxes the constraint on fast concentration measurement while preserving good accuracy on the flux calculation. In the frame of this PhD work, a sampling system dedicated to the DEC method for VOC flux measurement was developed. This device called MEDEE (Mesures par Échantillonnage Disjoint des Échanges d'Espèces en trace) relies on a novel technology that allows the rapid capture of an air parcel and insures its transfer at a constant pressure towards an on-line analyzer. It is composed of two mechanical syringes moved by electric actuators with an alternated functioning to supply continuously the analyzer. Three solenoid valves are installed on each reservoir to drive the sample flow depending on the cycle. A micro controller chip is used to give the rhythm of the whole system with millisecond accuracy. This sampling system has been built in chemically inert materials to avoid sample contamination or destruction; this makes MEDEE fully compatible with reactive species. MEDEE has been tested and validated on ground and aboard an aircraft, during two field campaigns. It was coupled to a fast isoprene sensor for BVOC flux measurements during two field campaigns in summers 2010 and 2011 above a downy oak forest. A Neural Network (NN) approach has been used to derive a biogenic VOC emission algorithm from these canopy level measured fluxes and concurrent environmental parameters. Isoprene emission modeling has been validated for the observed environmental conditions. In the future, such emission parameterization will be implemented in a coupled chemistry-dynamics model to study the impact of biogenic VOC emissions on air quality
34
Franco, Álvaro Junio Pereira. "Algoritmos para junções em digrafos acíclicos e uma aplicação na Antropologia." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/45/45134/tde-13022014-083516/.
Full textAbstract:
Neste trabalho consideramos um problema da Antropologia. A modelagem de sociedades e casamentos de indivíduos é feita com grafos mistos e encontrar caminhos disjuntos é uma questão central no problema. O problema é NP-completo e, quando visto como um problema parametrizado, ele é W[1]-difícil. Alguns subproblemas que surgem durante o processo de obter uma solução para o problema, envolvem caminhos disjuntos e podem ser resolvidos em tempo polinomial. Implementamos algoritmos polinomiais que são usados em uma ferramenta desenvolvida para solucionar o problema na Antropologia considerado. Nossa solução funcionou bem para as sociedades fornecidas pelos nossos parceiros.In this work we consider a problem from the Anthropology. The model of the societies and the marriages of individuals is done with mixed graphs and to find disjoint paths is a central question in the problem. The problem is NP-complete and W[1]-hard when it is considered a parameterized problem. Some subproblems that arise during the process to obtain a solution for the problem, involve disjoint paths and can be solved in polynomial time. We implemented some polynomial algorithms that are used in a tool developed to solve the problem in the Anthropology considered. Our solution worked well for the societies provided by our partners.
35
Beyersdorff, Olaf. "Disjoint NP-pairs and propositional proof systems." Doctoral thesis, [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=981087590.
Full text
36
Monreal, Garcies Jaume. "Generació additiva de funcions d'agregació conjuntives i disjuntives discretes." Doctoral thesis, Universitat de les Illes Balears, 2012. http://hdl.handle.net/10803/97298.
Full textAbstract:
En aquest treball es defineix el concepte de generador additiu de t–normes i de t–conormes discretes. S’hi estableixen resultats generals sobre la generació additiva de disjuncions i les caracteritzacions dels generadors de les t–conormes bàsiques. Es planteja un algorisme per a decidir quan una disjunció és additivament generable, basat en l’algorisme Gamma de la teoria de convexitat. S’estudia la relació que hi ha entre la generació additiva amb la suma ordinal i amb l’anidament. S’introdueixen els conceptes de generador concau i generador convex. S’estudia la generació additiva de les disjuncions i les t–conormes suaus i bivalents sobre L*. S’insisteix amb l’aplicabilitat de la generació additiva quan es tracta de manejar la condició de T–transitivitat per a relacions d’indistingibilitat discretes. Finalment, s’estudia la relació que hi ha entre la generació additiva d’una t–conorma S i les propietats de l’S–implicació corresponent. Amb motiu de les propietats d’ordre i modus ponens generalitzat, es defineixen els generadors mixtos
37
(8082655), Gustavo A. Valencia-Zapata. "Probabilistic Diagnostic Model for Handling Classifier Degradation in Machine Learning." Thesis, 2019.
Find full textAbstract:
Several studies point out different causes of performance degradation in supervised machine learning. Problems such as class imbalance, overlapping, small-disjuncts, noisy labels, and sparseness limit accuracy in classification algorithms. Even though a number of approaches either in the form of a methodology or an algorithm try to minimize performance degradation, they have been isolated efforts with limited scope. This research consists of three main parts: In the first part, a novel probabilistic diagnostic model based on identifying signs and symptoms of each problem is presented. Secondly, the behavior and performance of several supervised algorithms are studied when training sets have such problems. Therefore, prediction of success for treatments can be estimated across classifiers. Finally, a probabilistic sampling technique based on training set diagnosis for avoiding classifier degradation is proposed
38
Muralikrishna, M. "Optimization of multiple-disjunct queries in a relational database system." 1988. http://catalog.hathitrust.org/api/volumes/oclc/18437414.html.
Full textAbstract:
Thesis (Ph. D.)--University of Wisconsin--Madison, 1988.Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 153-158).
39
Sabovljevic, Marko. "Genetic distances and phylogeography of selected disjunct moss populations in Europe /." 2008. http://hss.ulb.uni-bonn.de/diss_online/math_nat_fak/2006/sabovljevic_marko/index.htm.
Full text
40
Jarkovská, Martina. "Problematika překladu anglických disjunktů (typ "-ingly") do češtiny." Doctoral thesis, 2008. http://www.nusl.cz/ntk/nusl-292672.
Full textAbstract:
The present study is concerned with -ing participle base adverbs as one realization form of this word class and their Czech equivalents. The focus of our study is on -ingly adverbials especially in their sentence modifying function. Sentence modification is present in both languages, English and Czech; however, based on morphological and syntactic differences between the two languages, the means of Czech and English sentence modification do not always correspond. Above all, this is caused by the fact that -ingly adverbials, a productive class of disjuncts evaluating the content of the clause from the speaker's point of view, structurally more or less do not have Czech corresponding counterparts. In English -ing participle base adverbials can be regarded as condensed forms of clausal realization (surprisingly ~ it is surprising). Although in Czech such adverbial forms are structurally possible, they are not in common usage (překvapující ~ *překvapujícně). This often results in applying different means of attitudinal evalution as counterparts of -ingly disjuncts. Therefore a primary interest of this work is a comparison of morphological, syntactic and stylistic differences in the sentence modification between English and Czech. Unlike in Czech where the word order is flexible, in English the position of a...
41
Mendes, Sérgio Alexandre Figueiredo. "Cálculo de um par de caminhos maximamente disjuntos ou de um par de caminhos disjuntos nas avarias, de custo aditivo mínimo." Master's thesis, 2013. http://hdl.handle.net/10316/41651.
Full textAbstract:
Atualmente, com o crescente volume de tráfego em redes de telecomunicações, é de
extrema importância a proteção das ligações ponto a ponto estabelecidas ao longo da rede,
com o objetivo de evitar interrupções de serviço. Um SRLG (Shared Risk Link Group) é
um conjunto de elementos da rede que têm um risco comum de falha. Os protocolos de
encaminhamento podem distribuir informação acerca dos SRLG que podem afetar cada
arco da rede, pelo que se torna importante o desenvolvimento de algoritmos eficientes
para a determinação de caminhos disjuntos ou maximamente disjuntos nos SRLG.
Um par de caminhos disjuntos nas avarias é um par de caminhos totalmente disjuntos
ou que podem ter em comum elementos resilientes, ou seja que estão protegidos numa
camada inferior.
No presente trabalho, desenvolvido no âmbito de um contrato de I&D com a PT Inovação,
foram estudados e implementados vários algoritmos: em primeiro lugar um algoritmo
de cálculo de um par de caminhos maximamente disjuntos nos nós, de custo aditivo
mínimo, que garante que a solução obtida é ótima; em segundo lugar três algoritmos de
cálculo de um par de caminhos maximamente disjuntos nos nós e nos SRLG. Cada um
desses três algoritmos, propostos no âmbito deste trabalho, são extensões/adaptações de
heurísticas para a determinação de pares de caminhos disjuntos nos SRLG; finalmente
foi implementada uma heurística, que procura obter um par de caminhos totalmente disjuntos
nos nós, exceto em nós extremos de arcos resilientes partilhados por esse par de
caminhos.
Os algoritmos foram desenvolvidos tendo em vista a sua utilização em PCE (Path
Computation Element) integrados em equipamentos de redes GMPLS (Generalized Multiprotocol
Label Switching). Dado que os PCE integrados têm tipicamente recursos computacionais
(capacidade de processamento e quantidade de memória) limitados, procurouse
otimizar os algoritmos implementados.
Foram realizados testes de desempenho das rotinas implementadas, tendo-se verificado
que o algoritmo de cálculo de um par de caminhos maximamente disjuntos nos nós,
de custo aditivo mínimo, é perfeitamente adequado ao PCE utilizado nos testes. As implementações
dos algoritmos de cálculo de um par de caminhos maximamente disjuntos nos
nós e nos SRLG, mostraram poder ser utilizadas num PCE no plano de controlo desde que
o número de iterações permitido fosse limitado. A última heurística desenvolvida poderá
ser utilizada num PCE apenas no plano de gestão uma vez que os tempos de execução não
são compatíveis com a sua utilização no plano de controlo, para a rede fornecida pela PT
Inovação.Nowadays telecommunication networks face an increasing demand of traffic volume and an increasing need to provide an adequate quality of the service experienced by the users. Therefore the protection of point-to-point connections throughout the network becomes of the utmost importance, in order to avoid service interruptions. A SRLG (Shared Risk Link Group) is a set of network elements with common risk of failure. The routing protocols can consider the information on the SRLG affecting each network link. Therefore, the development of efficient algorithms for the calculation of SRLG-disjoint (or at least maximally disjoint) paths becomes a critical issue in this context. A failure-disjoint path pair is a path pair which is either totally disjoint or only has in common resilient elements (i.e. protected in a lower layer). In this work, which was developed in the context of a R&D contract with PT Inovação, several algorithms were studied and implemented: firstly, an algorithm for the calculation of a maximally node-disjoint path pair of min-sum cost, which guarantees finding an optimal solution; secondly, three algorithms for the calculation of a maximally node and SRLG-disjoint path pair, which are adaptations/extensions of existing heuristics for the calculation of a totally SRLG-disjoint path pair; lastly, a heuristic to calculate a pair of totally node-disjoint paths, except for extreme nodes of resilient links that are shared by that path pair. The algorithms were developed having in mind that they will be used in a PCE (Path Computation Element) in GMPLS (Generalized Multiprotocol Label Switching) networks devices, which are usually very limited in terms of computational resources (processing and memory). Some performance tests for comparison of the implemented algorithms were made. The algorithm for the calculation of maximally node-disjoint path pairs of min-sum cost is suitable for the considered PCE. As for the algorithms for the calculation of maximally node and SRLG-disjoint path pairs, they can be used in a PCE as long as the number of allowed iterations is adequate. The heuristic for the calculation of failure-disjoint path pairs can be used in a PCE but only in a management plane due to its long execution time.
42
Lin, Yu-Chi, and 林育綺. "A morphometric study of the disjunct distribution and differentiation of Idea leuconoe (Lepidoptera: Nymphalidae)." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/35028529501752894441.
Full textAbstract:
碩士國立臺灣師範大學
生命科學研究所
100
Species distribution usually reflects its physiological characters and survival restriction under environmental conditions. Disjunct distribution of species can be resulted from long-distance dispersal or vicariance. According to the phylogeny of the species and the history of its geographical distribution areas, we can infer which mechanism may be responsible to disjunct distribution of the species. Idea leuconoe, a famous butterfly belonging to Nymphalidae, form isolated populations on isolated on islands of Southeast Asia. The forming series of Ryukyu Islands and Taiwan was caused by sea level changes and volcanic events in the different geological time. In this study, land-mark analysis was used to evaluate the wing pattern similarity between different populations of Idea leuconoe including Okinawa Island, Yaeyama Island, northeastern Taiwan, Green Island, Ochid Island and Hengchun Peninsula. Three alternative hypothesized mechanisms causing disjunct distribution of I. leuconoe were tested. The variation of larval morphology at different site were also examined. The results of cluster analysis, principal component analysis (PCA) support that the disjunct distribution of I. leuconoe was caused by at least two dispersal events. Taxonomic treatments proposed by Sonan, who regarded the Green Island population as a uniqual subspecies was supported by all analysis in this study. The details of taxonomy and conservation issue are also discussed herein.
43
Sabovljevic, Marko [Verfasser]. "Genetic distances and phylogeography of selected disjunct moss populations in Europe / vorgelegt von Marko Sabovljevic." 2006. http://d-nb.info/980581338/34.
Full text
44
Lee, Yi-Feng, and 李藝鋒. "A improvement of Decision Tree using Association Rule Algorithms and Genetic Algorithms in Small Disjunct rules." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/08215693292176255752.
Full textAbstract:
碩士長庚大學
資訊管理研究所
93
The decision tree algorithm is used for classification in the field of data mining, but constructing optimal decision trees is an NP-complete problem. For this reason, some scholars use genetic algorithms (GAs) to solve this problem. However, the efficiency of GAs is not good enough so that some scholars use association rule to help not only constructing a better decision tree but improving the efficiency of GAs. On the other hand, some of the previous researches take the entire decision tree to proceed GAs generation. However, the accuracy of big disjuncts with GAs has limited improvement, hence some scholars use small disjuncts which produce shorter rules instead of the big one to improve the efficiency of GAs. Therefore, we want to construct a more accurate decision tree by using association rule mining and GAs in Small Disjunct and then propose a new decision tree algorithm. HAEGT, which can not only get classification rules with highly accurate but highly interpretability. The accuracy and interpretability of our algorithm are demonstrated through some experiment results with the UCI Machine Learning Repository. Besides, our algorithm can raise the efficiency of genetic algorithms in decision tree about 20% and can construct highly interpretability rules.
45
Meyers, Stephen C. "The biogeography of Plantago ovata Forssk. (Plantaginaceae)." Thesis, 2005. http://hdl.handle.net/1957/29677.
Full textAbstract:
Plantago ovata Forssk. (Plantaginaceae) is a winter annual species which, in North
America, inhabits desert and Mediterranean habitats of the southwest United States,
northwest Mexico and the Channel Islands of California and Mexico. In the eastern
hemisphere P. ovata inhabits desert regions ranging from the Canary Islands, across
northern Africa to western India. The wide disjunction between P. ovata in the western
and eastern hemispheres poses an interesting question as to the origin and biogeography
of the species. Previous authors have hypothesized that P. ovata was introduced to North
America over the Bering land bridge, from Asia, during the Miocene, or introduced
anthropogenically from Europe during the 18th century by Spanish settlers. In this study
we examined sequence data from the chloroplast trnL-trnF, trnS-trnG and psbA-trnH
regions, the nuclear ribosomal internal transcribed spacer (ITS) and a region 5' of the
TCP region of a CYCLOIDEA gene. Using a molecular clock based on an ITS calibration
within the Plantago genus, and a clock for plant chloroplast, we date a non-anthropogenic
introduction event, from the Old World to North America, approximately
200,000-650,000 years ago. This is consistent with a Pleistocene origin, and does not
support a Miocene origin of the disjunction. Based on a morphological survey of 552
specimens, from throughout the world range of P. ovata, we suggest the recognition of
four subspecific taxa. Molecular phylogenetic analysis of chloroplast DNA and nuclear
ribosomal DNA ITS sequences support this taxonomic treatment. Furthermore,
phylogenetic sequences of the CYCLOIDEA gene support the morphological data. Both
suggest the origin of North American P. ovata as a result of hybridization between Old
World P. ovata varieties. This event provides further evidence that hybridization may
serve as a predictor of invasiveness in plants.Graduation date: 2005
46
Palmer, Jonathan M. "Morphological and molecular characterization of Mycorrhizal fungi associated with a disjunct stand of American chestnut (Castanea dentata) in Wisconsin /." 2006. http://digital.library.wisc.edu/1793/28905.
Full text
47
Au, Robert C. F. "Ring-width and δ13C chronologies from Thuja occidentalis L. trees growing at the northwestern limit of their distribution, central Canada." 2010. http://hdl.handle.net/1993/3853.
Full textAbstract:
Stable carbon isotope ratios (δ13C) in tree-ring cellulose are modified by environmental conditions occurring during carbon fixation. Researchers have however not reached a consensus as to whether extractives, lignin and/or hemicelluloses, all with specific isotopic signatures, should be removed prior to dendroisotopic analysis. The topic of the first paper dealt with the comparison of Thuja occidentalis L. wood components and their suitability for subsequent dendroisotopic analyses. It was recommended that holocellulose be isolated since an alpha-cellulose yield may be too low for subsequent mass spectrometer analysis, especially when narrow rings are encountered and multiple stable isotope analyses are to be performed per sample.
The second paper investigated the associations between the ring-width and δ13C chronologies with climate variables. The δ13C chronology spanned from 1650 to 2006 A.D. and incorporated dead and living T. occidentalis trees selected from two sites in central Manitoba, Canada. Compared to the δ13C values, ring width was more often associated with climate conditions in the year prior to ring formation. However, moisture stress was limiting for both radial growth and carbon assimilation. During the year of ring-formation, ring width was associated with spring and early summer conditions whereas, δ13C was more indicative of overall summer conditions. Nonetheless, each of ring width and δ13C contained individualistic climate information which could be used in tandem for long-term climate reconstruction.
48
Ferreira, Sofia Marques. "Determinação do caminho mais curto e respectivo caminho de protecção." Master's thesis, 2015. http://hdl.handle.net/10316/40484.
Full text
49
Le, Roux J. C. "A grammatical analysis of the Tswana adverbial." Thesis, 2007. http://hdl.handle.net/10500/1609.
Full textAbstract:
Adverbial constructions are a problematic subject in Tswana grammatical studies. Traditionally termed descriptives, it is not clear what the defining features of this category are. It is also a very vast category. There seems to be many different structures functioning as adverbials in Tswana, including particles, words, prepositional phrases and clauses. Tswana grammars in general often have little to say about the syntax of adverbials, in respect of, for instance, the propensity of Tswana adverbials for multiple occurrences in the same clause and the range of possible positions of Tswana adverbials in clause structure. Because of the vastness of the adverbial category we only deal with adverbials as elements of clause structure.
A typical feature of adverbials is the considerable mobility they enjoy in relation to other elements in clause structure which affects their grammatical and semantic status in relation to such elements. By distinguishing different categories of adverbials, in clause structure it becomes clear that the same structural element may function within different adverbial categories. This necessitates a definition of adverbials which is based on their specific semantic functions within clause structure.
The study is divided into five chapters. When dealing with the adverbial as a clause element in Tswana, we realise that it is not sufficiently described. The first two chapters therefore serve as an introduction to central theoretical issues where some relevant research is critically examined and related to the present study. In the next chapter, that is Chapter 3, we establish formal and semantic frameworks for the classification and descriptive treatment of adverbials in Tswana. In Chapter 4 we implement the structural, syntactic and semantic properties as well as the features adverbials have as modifiers to make a functional classification of adverbials in clause structure. The classification of adverbials as adjuncts, subjuncts, disjuncts and conjuncts from A Comprehensive grammar of the English language by Quirk, et al. (1985) (CGEL) is taken as the basis for this classification. Chapter 5 presents the overall conclusions and implications of the study.African Languages
D.litt. et Phil. (African Languages)
50
Raposo, Luis Miguel Carvalho. "Determinação de ligações ponto multi-ponto com restrições." Master's thesis, 2015. http://hdl.handle.net/10316/40462.
Full text