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Dissertations / Theses on the topic 'Rank 3'
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Tong, Viet Hung Phi. "Rank 3 permuation characters and maximal subgroups." Thesis, University of Birmingham, 2009. http://etheses.bham.ac.uk//id/eprint/290/.
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Let G be a transitive permutation group acting on a finite set E. Let P be a stabilizer in G of a point in E. We say G is primitive rank 3 on E if P is maximal in G and P has exactly three orbits on E. For any subgroup H of G, we denote by 1 \(\frac{G}{H}\) the permutation character or permutation module over the complex number field of G on the cosets G/H. Let H and K be subgroups of G. We say 1 \(\frac{G}{H}\) \(\leq\) 1\(\frac{G}{K}\)if 1 \(\frac{G}{K}\) \(\leq\) -1\(\frac{G}{H}\)is either 0 or a character of G. Also a finite group G is called nearly simple primitive rank 3 on E if there exists a quasi-simple group L such that L/Z(L) \(\triangleleft\) G/Z(L) \(\leq\) Aut(L/Z(L)) and G acts as a primitive rank 3 permutation group on some cosets of a subgroup of L. In this thesis we classify all maximal subgroups M of a class of nearly simple primitive rank 3 groups G acting on E such that 1 \(\frac{G}{H}\) \(\leq\) 1 \(\frac{G}{H}\) where P is a stabilizer of a point in E. This result has an application to the study of minimal genus of algebraic curves which admit group actions.
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Ahmadinezhad, Hamid. "Del Pezzo fibrations and rank 3 Cox rings." Thesis, University of Kent, 2011. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.544067.
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Grazian, Valentina. "Fusion systems on ρ-groups of sectional rank 3." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7670/.
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In this thesis we study saturated fusion systems on ρ-groups having sectional rank 3, for ρ odd. We obtain a complete classification of simple fusion systems on p-groups having sectional rank 3 for ρ ≥ 5, exhibiting a new simple exotic fusion system on a 7-group of order 7^5. We introduce the notion of pearls, defined as essential subgroups isomorphic to the groups C_ρ X_ρ and ρ₊¹⁺² (for odd), and we illustrate some properties of fusion systems involving pearls. As for ρ = 3, we determine the isomorphism type of a certain section of the 3-groups considered.
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Fan, Chun-Lin. "Extensions of stable rank-3 vector bundles on ruled surface /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?MATH%202004%20FAN.
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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004.Includes bibliographical references (leaves 20-21). Also available in electronic version. Access restricted to campus users.
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Ramchandani, Ritesh. "Rank-Based Methods for Survival Data With Multiple Outcomes." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:23845423.
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In clinical studies of survival, additional endpoints on patients may be collected over the course of the study that give additional insight into a treatment's effect. We propose three methods to analyze right censored survival data in the presence of multiple outcomes. In order to make limited parametric assumptions on the data-generating mechanisms, the methods are based on Wilcoxon-type rank statistics. Each method is applied to a recent clinical trial of Ceftriaxone in patients with amyotrophic lateral sclerosis.
In chapter 1, we modify the Gehan-Wilcoxon test for survival to account for auxiliary information on intermediate disease states (e.g. progression) that subjects may pass through before failure. We use multi-state modeling to compute expected ranks for each subject conditional on their last observed disease states and censoring time, and these ranks form the basis of our test statistic. Simulations demonstrate that the proposed test can improve power over the log-rank and generalized Wilcoxon tests in some settings while maintaining the nominal type 1 error rate.
In chapter 2, we propose an estimator for an accelerated failure time model based on the test statistic proposed in chapter 1. We use the statistic as an estimating equation for a parameter that accelerates the time to each subsequent disease state. The estimator incorporates the intermediate states in a manner relevant to the survival outcome, yielding interpretable treatment and covariate effects that consider the entire trajectory of the patient. Simulations demonstrate that the estimator is unbiased, and that the proposed standard error estimator is near the empirical value.
In chapter 3, we aim to assess the treatment effect globally across any types of multiple endpoints. The test we propose is based on a simple scoring mechanism applied to each pair of subjects for each endpoint. The scores for each pair of subjects are then reduced to a summary score, and a rank-sum test is applied to the summary scores. This can be seen as a generalization of several other global rank tests in the literature. Additionally, for certain statistics we describe optimal weighting schemes with respect to statistical power, and provide a method of selecting outcome weights adaptively.Biostatistics
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Strazzullo, Francesco. "Symmetry Analysis of General Rank-3 Pfaffian Systems in Five Variables." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/449.
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In this dissertation we applied geometric methods to study underdetermined second order scalar ordinary differential equations (called general Monge equations), nonlinear involutive systems of two scalar partial differential equations in two independent variables and one unknown and non-Monge-Ampere Goursat parabolic scalar PDE in the plane. These particular kinds of differential equations are related to general rank-3 Pfaffian systems in five variables. Cartan studied these objects in his 1910 paper. In this work Cartan provided normal forms only for some general rank-3 Pfaffian systems with 14-, 7-, and 6-dimensional symmetry algebra. We applied our normal forms to
[i] sharpen Cartan's integration method of nonlinear involutive systems,
[ii] classify all general Monge equations with a freely acting transverse 3-dimensional symmetry algebra, of which many new examples are presented, and
[iii] provide a broad classification of non-Monge-Ampere Darboux integrable hyperbolic PDE in the plane.
We developed a computer software, called FiveVariables, that classifies general rank-3 Pfaffian systems. FiveVariables runs in the environment DifferentialGeometry of Maple, version 11 and later.
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Xie, Yi. "On the Framed Singular Instanton Floer Homology From Higher Rank Bundles." Thesis, Harvard University, 2016. http://nrs.harvard.edu/urn-3:HUL.InstRepos:33493482.
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In this thesis we study the framed singular instanton Floer homology defined by by Kronheimer and Mrowka in \cite{KM3}.
Given a 3-manifold $Y$ with a link $K$ and $\delta \in H^2(Y,\mathbb{Z})$ satisfying a non-integral condition, they define the singular instanton Floer homology group $I^N(Y,K,\delta)$ by counting singular flat $PSU(N)$-connections with fixed holonomy around $K$.
Take a point $x\in Y\backslash K$, classical point class operators $\mu_i (x)$ of degree $2i$ on $I^N(Y,K,\delta)$ can be defined as in the original Floer theory defined by smooth connections.
In the singular instanton Floer homology group $I_\ast^N(Y,K,\delta)$, there is a special degree 2 operator $\mu (\sigma)$ for $\sigma \in K$. We study this new operator and obtain a universal relation between this operator and the point class operators $\mu_i (x)$.
After restricted to the reduced framed Floer homology $F\bar{I}_\ast^N(Y,K)$, these point classes operators $\mu_i (x)$ become constant numbers related to the $PSU(N)$-Donaldson invariants of four-torus $T^4$.
Then the universal relation becomes a characteristic polynomial for the operator $\mu(\sigma)$ so that we can understand the eigenvalues of $\mu(\sigma)$ and decompose the Floer homology as eigenspaces.Mathematics
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Frisch, Jérôme [Verfasser], Ernst [Akademischer Betreuer] Rank, Takayuki [Akademischer Betreuer] Aoki, and Christoph van [Akademischer Betreuer] Treeck. "Towards Massive Parallel Fluid Flow Simulations in Computational Engineering / Jérôme Frisch. Gutachter: Takayuki Aoki ; Ernst Rank ; Christoph van Treeck. Betreuer: Ernst Rank." München : Universitätsbibliothek der TU München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:91-diss-20141010-1222749-0-3.
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Grout, Jason Nicholas. "The Minimum Rank Problem Over Finite Fields." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd1995.pdf.
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Knežević, Jovana Verfasser], Ernst [Akademischer Betreuer] Rank, Christopher R. [Akademischer Betreuer] Johnson, and Hans-Joachim [Akademischer Betreuer] [Bungartz. "A high-performance computational steering framework for engineering applications / Jovana Knežević. Gutachter: Christopher R. Johnson ; Hans-Joachim Bungartz ; Ernst Rank. Betreuer: Ernst Rank." München : Universitätsbibliothek der TU München, 2013. http://nbn-resolving.de/urn:nbn:de:bvb:91-diss-20130729-1141219-0-3.
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Appiah, Isaac Kwadwo. "The classsification of fuzzy subgroups of some finite Abelian p-groups of rank 3." Thesis, University of Fort Hare, 2016. http://hdl.handle.net/10353/2468.
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An important trend in fuzzy group theory in recent years has been the notion of classification of fuzzy subgroups using a suitable equivalence relation. In this dissertation, we have successfully used the natural equivalence relation defined by Murali and Makamba in [81] and a natural fuzzy isomorphism to classify fuzzy subgroups of some finite abelian p-groups of rank three of the form Zpn + Zp + Zp for any fixed prime integer p and any positive integer n. This was achieved through the usage of a suitable technique of enumerating distinct fuzzy subgroups and non-isomorphic fuzzy subgroups of G. We commence by giving a brief discussion on the theory of fuzzy sets and fuzzy subgroups from the perspective of group theory through to the theory of sets, leading us to establish a linkage among these theories. We have also shown in this dissertation that the converse of theorem 3.1 proposed by Das in [24] is incorrect by giving a counter example and restate the theorem. We have then reviewed and enriched the study conducted by Ngcibi in [94] by characterising the non-isomorphic fuzzy subgroups in that study. We have also developed a formula to compute the crisp subgroups of the under-studied group and provide its proof. Furthermore, we have compared the equivalence relation under which the classification problem is based with various versions of equivalence studied in the literature. We managed to use this counting technique to obtain explicit formulae for the number of maximal chains, distinct fuzzy subgroups, non-isomorphic maximal chains and non-isomorphic fuzzy subgroups of these groups and their proofs are provided.
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Coles, Ben. "Conjugacy in braid groups and the LKB representation, and Bessis-Garside groups of rank 3." Thesis, University of Warwick, 2017. http://wrap.warwick.ac.uk/90207/.
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In the first part of this thesis, we give a survey of the conjugacy problem in the braid group, describing the solution provided by Garside theory, and outlining the progress that has been made towards a polynomial time solution in recent years using refinements of Garside's solution, and the Thurston-Nielsen classification of braids, which reduces the problem to the case of pseudo-Anosov braids. Using the faithful Lawrence-Krammer-Bigelow representation of the braid groups, we consider how the eigenspaces of pseudo-Anosov braids can under certain conditions yield invariants of their conjugacy class and thus lead us towards a polynomial time solution of the conjugacy problem. In the second part we introduce Bessis-Garside groups, a generalisation of the methods used by Bessis in his papers on dual braid monoids. We consider the groups given by taking the quotient of the free group by the orbits of its generators under the action of some subgroup of the braid group, and find that in many cases this construction can give us a group with a Garside structure. By means of introduction we review the simple rank 2 case, and summarise examples of such groups already known to admit Garside structures, in particular due to the work of Digne. We then go on to give all those of such groups which can be found as quotients of affine and spherical Artin groups of rank 3. We show that all such groups may be given a cycle presentation, or equivalently may be given as labelled-oriented-graph presented groups, and give conditions on such presentations that are equivalent to the group admitting a `dual' Garside structure. Restricting by the cycle lengths occurring in such presentations we give all Bessis-Garside groups of rank 3 which have all cycles length at most 4, and discuss the case of Bessis-Garside groups with uniform cycle length.
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Mecklenburg, Trinity. "Elliptic Curves." CSUSB ScholarWorks, 2015. https://scholarworks.lib.csusb.edu/etd/186.
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The main focus of this paper is the study of elliptic curves, non-singular projective curves of genus 1. Under a geometric operation, the rational points E(Q) of an elliptic curve E form a group, which is a finitely-generated abelian group by Mordell’s theorem. Thus, this group can be expressed as the finite direct sum of copies of Z and finite cyclic groups. The number of finite copies of Z is called the rank of E(Q).
From John Tate and Joseph Silverman we have a formula to compute the rank of curves of the form E: y2 = x3 + ax2 + bx. In this thesis, we generalize this formula, using a purely group theoretic approach, and utilize this generalization to find the rank of curves of the form E: y2 = x3 + c. To do this, we review a few well-known homomorphisms on the curve E: y2 = x3 + ax2 + bx as in Tate and Silverman's Elliptic Curves, and study analogous homomorphisms on E: y2 = x3 + c and relevant facts.
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Guevara, Carlos Rafael Payares. "As 2-álgebras de Lie simples de posto toral 3." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/45/45131/tde-31032017-141121/.
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Neste trabalho estudamos as 2-álgebras de Lie simples, de dimensão finita e de posto toral 3, sobre um corpo algebricamente fechado de característica 2. Nós conjecturamos que a única 2-álgebra de Lie simples de este tipo é W(1, 3). Assim, nosso principal objetivo é verificar a veracidade desta conjectura para estas álgebras de pequenas dimensões. Como resultados, provamos que esta conjectura é certa para todas estes álgebras de dimensão menor ou igual a 16, e também em alguns casos especiais quando a dimensão é 17.In this work we study the simple Lie 2-algebras of finite dimension, and toral rank 3 over an algebraically closed field characteristic 2. We surmise that the only simple Lie 2-algebra of this type is W(1, 3). So, our main objective is to study the truthful of this conjecture for these algebras of small dimensions. As a result, we prove that this conjecture is true for all these algebras less than or equal to 16 dimension, and also in some special cases when the dimension is 17.
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Heydel, Max Christian [Verfasser], and Lynn [Akademischer Betreuer] Heller. "A rank 2 theory for constrained Willmore tori in the 3-dimensional sphere / Max Christian Heydel ; Betreuer: Lynn Heller." Hannover : Gottfried Wilhelm Leibniz Universität, 2021. http://d-nb.info/123513847X/34.
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Barth, Fabrício Jailson. "Recuperação de documentos e pessoas em ambientes empresariais através de árvores de decisão." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/3/3141/tde-15092009-164430/.
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Este trabalho avalia o desempenho do uso de árvores de decisão como função de ordenação para documentos e pessoas em ambientes empresariais. Para tanto, identificouse atributos relevantes das entidades a serem recuperadas a partir da análise de: (i) dinâmica de produção e consumo de informações em um ambiente empresarial; (ii) algoritmos existentes na literatura para a recuperação de documentos e pessoas; e (iii) conceitos utilizados em funções de ordenação para domínios genéricos. Montou-se um ambiente de avaliação, utilizando a coleção de referência CERC, para avaliar a aplicabilidade do algoritmo C4.5 na obtenção de funções de ordenação para o domínio empresarial. O uso do algoritmo C4.5 para a construção de funções de ordenação mostrou-se parcialmente efetivo. Para a tarefa de recuperação de documentos não trouxe resultados bons. Porém, constatou-se que é possível controlar a forma de construção da função de ordenação a fim de otimizar a precisão nas primeiras posições do ranking ou otimizar a média das precisões (MAP). Para a tarefa de recuperação de pessoas o algoritmo C4.5 obteve uma árvore de decisão que consegue resultados melhores que todas as outras funções de ordenação avaliadas. OMAP obtido pela árvore de decisão foi 0, 83, enquanto que a média do MAP das outras funções de ordenação foi de 0, 74. Percebeu-se que a árvore de decisão utilizada para representar a função de ordenação contribui para a compreensão da composição dos diversos atributos utilizados na caracterização dos documentos e pessoas. A partir da análise da árvore de decisão utilizada como função de ordenação para pessoas foi possível entender que uma pessoa é considerada especialista em algum tópico se ela aparecer em muitos documentos, aparecer muitas vezes nos documentos e os documentos onde aparece têm uma relevância alta para a consulta.This work evaluates the performance of using decision trees as ranking functions for documents and people in enterprises. It was identified relevant attributes of the entities to be retrieved from the analysis of: (i) the production and consumption of information behavior in an enterprise, (ii) algorithms for documents and people retrieval at literature, and (iii) the concepts used in ranking functions for generic domains. It was set up an evaluation environment, using the CERC collection, to evaluate the applicability of the C4.5 algorithm to obtain a ranking function for the enterprise domain. The use of C4.5 algorithm for the construction of ranking function was proved to be partially effective. In the case of documents retrieval the C4.5 has not found good results. However, it was found that is possible to control the way of building the ranking function in order to optimize the precision in the first positions of the ranking or optimize the mean average precision (MAP). For the task of people retrieval the C4.5 algorithm developed a ranking function that obtain better results than all other ranking functions assessed. The value of MAP obtained by decision tree was 0, 83, while the average MAP of other ranking functions was 0, 74. The decision tree used to represent the ranking function contributes to understanding the attributes composition used in the characterization of documents and people. Through the analysis of the decision tree used as ranking function for people, we could realise that a person is considered expert in any topic if he/she appear in many documents, appear many times in same documents and documents where he/she appears have a high relevance to the query.
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Motyčka, Jan. "Implementace mechanismů zajišťujících “RAN Slicing” v simulačním nástroji Network Simulator 3." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442360.
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This thesis deals with the topic of network slicing technology in 5G networks, mainly on the RAN part. In the theoretical part, basic principles of 5G network slicing in core network part and RAN part are presented. Practical part contains a simulation scenario created in NS3 simulator with LENA 5G module. Results of this simulation are presented and discussed with the emphasis on RAN slicing.
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Mignard, Guillaume. "Rang et courbure des 3-tissus du plan et applications aux équations différentielles." Bordeaux 1, 1999. http://www.theses.fr/1999BOR10507.
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On s'interesse a la geometrie locale des tissus de c 2 (i. E. Aux configurations formees de feuilletages analytiques complexes en position generale) et notamment a leurs invariants analytiques. Apres un apercu sur quelques exemples de tissus (tissus algebriques, tissus issus de phenomenes optiques lies aux caustiques) on presente des resultats classiques motivant ce travail et une premiere condition d'hexagonalite dans le cas des 3-tissus lineaires. On determine le rang et la courbure de blaschke d'un 3-tissu de c 2, en etudiant le systeme de la resonance qui lui est associe, grace a des resultats de base de la theorie des d-modules. On developpe une methode explicite de reformulation d'expressions differentielles symetriques (i. E. Une forme de generalisation differentielle du theoreme sur les fonctions symetriques), utile a l'etude de la geometrie des equations differentielles du 1 e r ordre de degre 3, uniquement a partir de leurs coefficients. On exhibe ainsi des conditions sur ces coefficients necessaires et suffisantes a l'hexagonalite ou a la linearite de la famille des courbes integrales de ces equations (i. E. Du 3-tissu qui leur est associe). Ce travail se termine en appliquant les resultats obtenus a l'etude de quelques exemples.
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Petit, Edgar. "Fibrés vectoriels algébriques de rang 3 sur le plan projectif à cohomologie naturelle." Nice, 1986. http://www.theses.fr/1986NICE4058.
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On dit qu'un faisceau cohérent f sur un espace projectif possède la cohomologie naturelle si pour tout produit tensoriel de f par un fibre en droites, au plus un groupe de cohomologie de ce produit est non nul. L'objet de cette thèse est la démonstration du théorème suivant : les fibres stables génériques de rang 3 sur le plan projectif ont la cohomologie naturelle. On établira de plus un critère faisant intervenir les classes de Chern, déterminant une condition nécessaire et suffisante à l'existence de fibres de rang 3 (stables ou non) sur le plan projectif et possédant la cohomologie naturelle
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Ben, Nasr Nabil. "Aérodynamique 3-D : application au bruit des soufflantes des turboréacteurs." Paris 6, 2010. http://www.theses.fr/2010PA066117.
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La réduction du bruit des avions aux environs des zones aéroporturaires est devenu un enjeu socio-économique majeur. En effet, du fait de l'augmentation continue du nombre de vol, mais aussi de la capacité, et donc de la taille des avions, le traffic aérien est en constante croissance. De par les forts niveaux sonores émis par les aéronefs, cette croissance compromet l'intégration harmonieuse de l'activité aéronautique commerciale au sein de l'environnement. C'est pourquoi avionneurs et motoristes se soucient de plus en plus de la réduction des émissions acoustiques. Si la réduction du bruit des avions est une notion claire, elle s'avère être un problème des plus difficiles. Les divers émissions sonores au décollage ou en approche font intervenir des mécanismes physiques nombreux et encore mal connus. Le conseil consultatif pour la recherche aéronautique en Europe a fixé deux objectifs : répondre aux besoins de la société en terme de transport aérien plus efficace, plus sûre et respectueux de l'environnement et assurer la compétitivité de l'industrie aéronautique européenne. Afin de pouvoir répondre à cet objectif, la Communauté européenne a mis sur pieds des projets, dont : PROBAND et VITAL pour pouvoir comprendre d'une part les phénomènes et les sources acoustiques du bruit à large bande et d'étudier des configurations innovantes. Cette thèse a donc pour but de réaliser des calculs stationnaires (RMS-RANS) et instationnaires (RMS-RANS en utilisant l'approche chorochronique) pour des configurations de turboréacteurs à double flux et fournir les données nécessaires afin de pouvoir prédire le niveau acoustique émit.
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Akin, Cigdem. "Detection Of Species Boundaries In The Rana Ridibunda Complex Of Southwestern Turkey Using Mitochondrial Nd3 Marker." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/3/12608156/index.pdf.
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Water frogs are one of the most interesting vertebrate groups, showing great diversity and complexity in their reproductive modes, ecology and evolutionary relationships, and with many cryptic species due to high morphological similarity. For many decades, a single species, Rana ridibunda, has been suggested to exist in Turkey. However, the application of new morphometric, molecular and bioacoustic techniques has recently revealed the occurrence of several distinct water frog taxa in Turkey.
In this study, 340 bp long mtDNA ND3 region in 195 specimens was sequenced and subjected to phylogenetic analyses to detect geographical structure and species boundaries. Neighbor joining tree, minimum spanning network, SAMOVA and AMOVA were used to understand relationship within and among clades. Population demography was studied through mismatch distribution and neutrality tests.
Results indicated that populations in southwestern Turkey show high diversity and strong geographic structuring. In Turkey there are four major maternal lineages, each probably representing a species: Thrace lineage represents Rana ridibunda Pallas 1771 in European TurkeyCeyhan lineage indicates an unnamed taxon in Cilicia plain
South-central lineage occurs at the Lake District, Antalya, Konya and Karaman provinces and represents Rana caralitana Arikan, 1988
Anatoliaca lineage (occuring in Asiatic Turkey except for central southern Turkey, Rhodes &
Karpathos, northeastern Syria, and probably also Iraq and Transcaucasia) is designated either as Rana cerigensis Beerli, Hotz, Tunner, Heppich, and Uzzell 1994 or as a new subspecies of R. caralitana, based on the degree of reproductive isolation present between the last two lineages.
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Zacharos, Athanasios. "The Use of Unsteady RANS in the Computatoins of 3-Dimensional Flows in Rotating Cavities." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.511908.
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Arntz, Aurélien. "Civil aircraft aero-thermo-propulsive performance assessment by an exergy analysis of high-fidelity CFD-RANS flow solutions." Thesis, Lille 1, 2014. http://www.theses.fr/2014LIL10110/document.
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Les outils et méthodologie utilisés actuellement par les ingénieurs ne permettent pas d’évaluer efficacement l’intérêt de ces concepts innovants. Typiquement, le conventionnel partage poussée/traînée devient excessivement ambigu pour l’étude de systèmes propulsifs avec ingestion de couches limites. Par ailleurs, le management thermique devient un enjeux crucial pour les performances globales de l’appareil. Le travail a donc consisté à développer une méthodologie capable de prendre en compte ces différents aspects. Dans un premier temps, une formulation théorique basée sur la notion d’exergie a été développée. Une analyse du fluide contenu dans un volume de contrôle autour de l’appareil basée sur la quantité de mouvement et sur le premier et le second principes de thermodynamique a permis d’aboutir à une équation bilan qui met en relation l’exergie délivrée par convection (système propulsif) ou par conduction (transfert de chaleur), l’équilibre mécanique de l’avion et les principaux phénomènes fluides à l’origine de la destruction d’exergie. Cette formulation théorique a ensuite été implémentée numériquement dans un code Fortran afin de pouvoir post-traiter des solutions haute-fidélité CFD-RANS. La précision et la robustesse de ce code a été évaluée dans un second temps pour des configurations non propulsées qui ont l’avantage de faire intervenir des méthodes éprouvées pour la détermination de la traînée subi par ces solides. Enfin, la formulation et le code on été utilisés pour la détermination des performances de configurations qui échangent de l’énergie (mécanique ou thermique) avec le fluide environnantThe tools and methodologies currently used for the design of commercial aircraft have been initiated decades ago and are based on simplifying assumptions that become excessively ambiguous for highly-integrated propulsion devices for which traditional drag/thrust bookkeepings become inapplicable. Likewise, the growing complexity of civil aircraft requires a more global performance assessment which could take into account thermal management. As a consequence, a new exergy-based formulation is derived for the assessment of the aerothermopropulsive performance of civil aircraft. The output of the derivation process is an exergy balance between the exergy supplied by a propulsion system or by heat transfer, the mechanical equilibrium of the aircraft, and the exergy outflow and destruction within the control volume. The theoretical formulation is subsequently numerically implemented in a Fortran code named ffx for the post-processing of CFD-RANS flow solutions. Unpowered airframe configurations are examined with grid refinement studies and a turbulence model sensitivity analysis. The code is thereby validated against well-tried methods of drag prediction or wind-tunnel testings when available. Finally, the investigation of powered configurations demonstrates the ability of the approach for the performance assessment of configurations with aerothermopropulsive interactions
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Silva, Carlos Roberto Ilário da. "Desenvolvimento de um novo método RANS-based para a aeroacústica computacional de jatos de alta velocidade." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/3/3150/tde-02072012-163931/.
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Uma nova ferramenta de aeroacústica computacional baseada em simulações RANS (Reynolds Averaged Navier-Stokes) foi desenvolvida para a predição do ruído gerado pelo escoamento tri-dimensional de jatos complexos. O método é denominado de LRT o qual surgiu da combinação da analogia acústica de Lighthill com o método de acústica geométrica Ray-Tracing. A grande vantagem da utilização do método LRT para predições de ruído é que este determina não apenas as fontes sonoras presentes no escoamento, mas também modela os efeitos da interação fluidoacústica e, sua influência no ruído em um campo distante. Esta característica tornou-se extremamente importante para a indústria de motores aeronáuticos já que investigações em bocais assimétricos estão atualmente em andamento devido à necessidade de redução de ruído. O método LRT é uma ferramenta relativamente rápida de predição de ruído de jatos baseado na Analogia Acústica de Lighthill e que usa como dados de entrada os resultados obtidos à partir de uma simulação RANS do escoamento. A interação fluidoacústica é calculada através da utilização da Teoria de Traçamento de Raios. O método LRT foi formulado como um método tri-dimensional e, portanto, não possui limitações de aplicabilidade para a predição sonora em relação ao tipo de escoamento ou à geometria do bocal. Diversas simulações numéricas foram conduzidas com sucesso para uma grande variedade de escoamento de jatos (jatos simples, coaxiais e assimétricos) utilizando o LRT como uma ferramenta de engenharia. O resultado deste trabalho é uma ferramenta numérica que permite a realização de predições de ruído para casos de escoamento de jatos complexos, assim como possibilita sua aplicação para a investigação de efeitos de interação do escoamento do jato com superfícies hiper-sustentadoras no campo acústico. Adicionalmente, o método LRT pode ser aplicado para complementar análises experimentais possibilitando, portanto, um melhor entendimento sobre os mecanismos fluidodinâmicos e acústicos presentes em escoamentos de jatos complexos.A novel computational aeroacoustics tool based on RANS (Reynolds Averaged Navier-Stokes method) is developed for predicting the noise generated by complex three-dimensional jet flows. The new method is called LRT which arises from the combination of Lighthills acoustic analogy with Ray-Tracing acoustics. The powerful advantage of applying the LRT method for noise predictions is that it calculates not only the noise sources but it also models and takes into account sound-flow interaction effects without any geometric simplification, such as flow symmetries of the problem. This is now a strong requirement from aero-engines manufactures since investigations on asymmetric nozzles, as a means of noise reductions are in progress. The LRT method is a relatively fast jet noise prediction tool based on Lighthills Acoustic Analogy and it uses a Reynolds-Average Navier-Stokes (RANS) computational fluid dynamics (CFD) simulation as input information. The sound-flow interaction is computed by solving the propagation using Ray-Tracing equations. The LRT method has been formulated as a general three-dimensional method and it has no restrictions on the type of the flow field or nozzle geometry for noise prediction. Successful numerical noise predictions have been carried out for a variety of jet flows (single, coaxial and asymmetric jets) using the LRT as an engineering tool. The outcome from this thesis is a numerical tool that allows noise predictions of complex exhaust systems and the variations in sound field due to modifications of the flow field generated by the interaction of the jet flow with high-lift surfaces. In addition, the LRT method can be applied to complement experimental analysis providing a better understanding about the flow and acoustics mechanisms for complex jets.
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Rossato, Daniele. "Imunorreatividade à proteína c-FOS na medula espinal lombossacral e no gânglio da raiz dorsal de râs Rana catesbeiana 3 dias após a secção nervosa periférica." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2006. http://hdl.handle.net/10183/7688.
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A dor constitui uma experiência complexa, mediada por distintos sistemas de transmissão sendo integrados por diversos mecanismos neurais. Um dos modelos mais empregados para o estudo da dor neuropática é a secção nervosa periférica, a qual resulta em alterações neuroquímicas e neuroanatômicas em neurônios sensoriais primários e em seus territórios de projeção. Após a secção do nervo ciático, os mamíferos apresentam um aumento na expressão de genes precocemente expressos, como o c-Fos e o c-Jun, no corno dorsal da medula espinal. Animais não mamíferos, como os anfíbios, também vem sendo utilizados como modelos para os estudos dos mecanismos acerca da nocicepção. No presente estudo foi analisado o padrão de imunorreatividade à proteína c-Fos na medula espinal lombossacral e no gânglio da raiz dorsal (GRD) de rãs Rana catesbeiana em condições basais, bem como de rãs submetidas à manipulação e à secção do nervo ciático. Para isso foram utilizados animais adultos, de ambos os sexos, sendo que os mesmos foram sacrificados 3 dias após o procedimento cirúrgico. A técnica imunoistoquímica utilizada foi a do anticorpo não marcado de Sternberger (1979), sendo utilizado anticorpo primário do tipo policlonal, na concentração de 1:700. As alterações no padrão de imunorreatividade a esta proteína no GRD dos três grupos experimentais foram quantificadas através das técnicas de densitometria óptica e contagem neuronal. Para a quantificação da proteína c-Fos na medula espinal lombossacral dos 3 grupos experimentais, utilizou-se a técnica de western blot. Em GRD, a imunorreatividade foi mais pronunciada no citoplasma de neurônios de pequeno (10-20μm), médio (25-35μm), e grande 40-50μm) diâmetro dos 3 grupos experimentais. A manipulação e a secção do nervo ciático provocou aumento no número de núcleos imunorreativos de células de pequeno diâmetro. A densitometria óptica foi significativamente maior no citoplasma das células dos GRDs localizados ipsilateralmente quando comparada com aquela das células pertencentes aos GRDs localizados contralateralmente à lesão. Todavia, não houve diferenças estatisticamente significativa entre a imunorreatividade nuclear nos GRDs entre os 3 grupos experimentais. O número de células imunorreativas nestes gânglios não mostrou mudanças significativas nos 3 grupos experimentais. Na medula espinal, a imunorreatividade à proteína c-Fos ocorreu predominantemente em núcleos localizados nos campos terminais dorsal e ventral, na banda mediolateral, na região ventral medial do corno ventral e nos funículos lateral e ventral medial. Os neurônios motores sempre foram imunorreativos. A manipulação e a secção do nervo ciático resultaram em um acréscimo no número de núcleos imunorreativos localizados nos campos terminais dorsal e ventral, e banda mediolateral, sendo este aumento maior na região do campo terminal dorsal. As demais regiões não mostraram modificações significantes no padrão de imunorreatividade da proteína c-Fos. A expressão desta proteína não modificou significativamente nos 3 grupos experimentais. Estes resultados mostram que, em rãs, similar ao que ocorre em mamíferos, a ativação de fibras aferentes primárias ativam a proteína c-Fos. No entanto, diferente de mamíferos, esta proteína ocorre no citoplasma de células sensoriais. Assim, apesar das rãs constituírem excelentes modelos para o estudo do papel do c-Fos nos mecanismos da transmissão nociceptiva, os estudos futuros abordando esta questão deverão considerar esta particularidade das rãs.
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Bonne, Nicolas. "Stabilité de l'intéraction onde de choc/ couche limite laminaire." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLX025/document.
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Le phénomène d’interaction onde de choc/couche limite (CL) est omniprésent en aérodynamique. De manière générale, il génère des oscillations basses fréquences qui peuvent être néfastes pour les machines. L’exemple typique est le tremblement de l’onde de choc sur profil d’aile en régime transsonique, dangereux car il peut exciter les modes de structure de l’aile et potentiellement la rompre. Ce type de phénoménologies a été largement étudié en condition de CL amont turbulente, ce qui a donné lieu à des scénarios physiques crédibles et des méthodologies d’étude efficaces, notamment les analyses de stabilité sur champs turbulents moyennés (RANS). Toutefois la technologie laminaire, c’est-à-dire l’utilisation de CL laminaires en vue de réduire la consommation des aéronefs représente un nouveau challenge scientifique sur cette problématique. La physique est en effet fortement impactée par la nature laminaire de la CL, notamment du fait de la faible résilience de celle-ci aux gradients de pression adverses et à la transition turbulente. Cette thèse a ainsi porté les méthodes d’analyse de stabilité sur champ RANSpour les situations de CL laminaire. L’originalité et l'apport de l’étude résident dans la prise en compte des modèles de transition dans l’approchelinéarisée sur champ RANS. Les modèles utilisés (RANS et transition) ont donc été linéarisés afin de réaliser des études de stabilité en perturbant toutes les variables aérodynamiques. La validation de la méthode a été réalisée par comparaison avec des résultats expérimentaux et de simulation (LES) sur deux conifurations d'application. La première configuration est le cas de la réflexion d’un choc oblique sur une plaque plane. La deuxième est celle du choc droit à l’extrados d’un profil en condition transsonique. Ces deux cas sont en condition de CL laminaire à l'amont du choc.Des analyses de stabilité et de résolvent ont été réalisées.Ces approches ont permis de caractériser le comportement d’oscillateur/amplificateur des écoulements en question et d'analyser la physique des instationnarités observées dans les expériences.Le cas de la réflexion de choc est caractérisé par trois fréquences. L'analyse de stabilité montre que celles-ci ne correspondent pas à des modes globaux instables mais à une dynamique d'amplificateur de l'écoulement. L'analyse de résolvent identifie bien ces trois fréquences. L’analyse des réponses optimales, couplée à une analyse de stabilité locale, a ensuite permis de proposer des scénarios physiques de ces dynamiques.Dans le cas du choc droit sur profil en régime transsonique, l'écoulement apparaît globalement instable. Deux modes d'instabilité sont identifiés. Le premier à basse fréquence correspond au phénomène de tremblement observé en conditions turbulentes. Le deuxième apparaît à plus haute fréquence, et correspond à un mode d'oscillation de la bulle de séparation présente sous le pied de choc.Plus largement, la thèse permet de suggérer que certaines dynamiques dans ce type d’interaction procèdent de mécanismes similaires liés à la respiration de la bulle de séparation laminaireThe shock wave boundary layer (BL) interaction phenomenon is ubiquitous in aerodynamic. In general this interaction generates some low frequency oscillations which can be disastrous for the machines. The typical example is the buffet phenomenon on an airfoil in transonic conditions. Buffet is dangerous since its low frequency can excite the structural modes of the airfoil and break it. The phenomenology has been wildly studied when the incoming BL is turbulent. These studies have derived several credible scenarii and efficient methodologies to capture its dynamic, especially the stability analysis tools on an averaged turbulent flow (RANS). However laminar technologies, the use of laminar BL to reduce the fuel consumption of planes, represent a new scientific challenge on this problematic. In fact, the physic of the interaction is importantly impacted by the laminar nature of the BL especially because of its weak resilience to an adversed pressure gradient and of the transition to turbulence.The thesis deals with the methodologies for the stability analysis on a RANS base flow in the case of a laminar BL. The originality and the contribution of this work have been to take into account a transition criteria in the linearised dynamic on a RANS base flow. The model used (RANS and transition) have then been linearized in order to make a stability analysis which take into account all the aerodynamic varaibles. The validation of this methodology has been made by comparison to expermient and simulation (LES) on two configurations of application. The first one is a weak reflected shock wave on a flat plate. The second one is the strong shock around an airfoil in a transonic regime. In both cases the incoming BL is laminar.Stability and resolvent analysis have been made. These approches have been able to caratirized the ocillator/noise amplifier behavior of the flow and to enabled a physical analysis of the unsteadinesses observed in the experiments.The case of the reflected shock wave is caracterized by three frequencies. The stability analysis shows that they don't correspond to globally unstable modes but to a noise amplifier behavior of the flow. The resolvent analysis identifies the three frequencies. The analysis of the optimal response, coupled with a local stability analysis, enables to proposed physical scenarii of these dynamics.In the case of the strong shock on an airfoil in transonic regime, the flow is globally unstable. Two unstable modes have been identified. The first one, at low frequency, correspond to the buffet phenomenon also observed in the turbulent case. The second one appears at higher frequency and correspond to the oscillation of the separation bubble formed at the feet of the shock.More generally, this thesis suggests that some dynamics of these two interactions result from the same mecanism linked to the breathing motion of the laminar separation bubble
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Ortega, Ortega Angela. "Sur l'espace des modules des fibrés vectoriels de rang 3 sur une courbe de genre 2 et la cubique de Coble." Nice, 2003. http://www.theses.fr/2003NICE4032.
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Castro, Carlos José Rocha de Oliveira. "Simulação da interação casco-propulsor de uma embarcação usando mecânica dos fluidos computacional (CFD)." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/3/3135/tde-03072007-180315/.
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Este trabalho discute a questão da interação entre o casco do navio e o propulsor em funcionamento conjunto, e sua simulação por ferramentas computacionais. O texto se concentra em descrever os principais efeitos dessa interação, as principais dificuldades em se estimar esses efeitos, os métodos tradicionalmente usados, e como ferramentas computacionais podem ser aplicadas de maneira vantajosa. No texto também pode ser encontrada uma análise crítica dos métodos mais comuns e dos resultados, baseada em trabalhos de diversos autores, publicados nacional e internacionalmente. É apresentado o método dos volumes finitos, usado nesta pesquisa, algumas de suas particularidades principais, vantagens e desvantagens, e os resultados das simulações realizadas, interpretados à luz dos valores experimentais usados para comparação e das limitações do método dos Volumes Finitos. A comparação é feita analisando-se grandezas integrais, como a resistência do casco ou o empuxo do propulsor; e também as características do escoamento, como o perfil de velocidade na esteira, presença de vórtices, e outras estruturas típicas. Os resultados obtidos têm a mesma ordem de precisão dos que tem sido obtidos por outros pesquisadores, internacionalmente, e são coerentes qualitativamente; mas algumas questões referentes aos modelos físico e numérico escolhidos ainda limitam a precisão dos resultados e restringem sua adoção em atividades de engenharia. Entretanto, diversas características observadas no escoamento contribuem para aumentar o conhecimento de alguns fenômenos envolvidos no problema.This work is about the hull and propeller interaction in joint functioning, and its simulation by computational tools. The text concentrates in describing the main effects of such interaction, the main difficulties in the estimation of these effects, the methods traditionally adopted, and how computational tools can be applied in advantageous way. A critical analysis of the most common methods and results, based on paperworks of several different authors worldwide, can also be found. The Finite Volumes method, used in this research, is presented - its main issues, advantages and disadvantages, and the simulations outcomes, compared to the experimental values and explained by the knowledge of the Finite Volumes method limitations. The comparison is made by means of both integral values, such as the hull\'s resistance or the propeller thrust; as well as the characteristics of the flow, like the wake velocity profile, presence of vortex, and other typical structures. The results shows the same error band than the ones which has been obtained by other researchers, worldwide, and most of the typical characteristics of the flow were observed. But some issues concerned to the chosen physical and numerical models still limit the precision of the outcomes, and restrict the application of such models at engineering activities. But several insights about the flow, obtained at this study, can be useful to the understanding of some phenomena involved in the propeller operation.
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Rang, Carola Monika [Verfasser]. "Nicht symmetrische Graphenmoleküle mittels [3+2+1]-Benzanellierung und Untersuchungen von haptotropen Wanderungen auf Oberflächen / Carola Monika Rang. Mathematisch-Naturwissenschaftliche Fakultät der Uni Bonn." Bonn : Universitäts- und Landesbibliothek Bonn, 2010. http://d-nb.info/1000980901/34.
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Myneni, Sudha Rani [Verfasser]. "Role of the anterior Hox genes in segment-specific NB7-3 lineage development in the embryonic central nervous system of Drosophila melanogaster / Sudha Rani Myneni." Mainz : Universitätsbibliothek Mainz, 2016. http://d-nb.info/1112624902/34.
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Momplot, Adrien. "Modélisation tridimensionnelle des écoulements en réseau d’assainissement : Evaluation des modèles RANS à travers l’étude des écoulements au droit d’ouvrages spéciaux." Thesis, Lyon, INSA, 2014. http://www.theses.fr/2014ISAL0125.
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La modélisation à l’aide de l’approche RANS (Reynolds Averaged Navier Stokes) a été menée en trois dimensions, en considérant les régimes permanent et non permanent, dans le but de simuler les écoulements au niveau des jonctions, bifurcations et déversoirs d’orage. A travers ces trois exemples d’étude, plusieurs stratégies de modélisation (différentes combinaison lois de paroi/modèles de turbulence, différents algorithmes de couplage pression/vitesse, différents schémas de discrétisation spatiale, différentes conditions aux limites, différents types et tailles de maille, etc.) ont été testées et évaluées à l’aide de plusieurs indicateurs de performance (de type RMS –Root Mean Square) en s’appuyant sur les données de vitesses (vitesses moyennes in situ et champs de vitesses obtenus par PIV en laboratoire), hauteurs d’eau, débits (répartition de débits en bifurcation en laboratoire ou débits déversés in situ). Les résultats obtenus sont transposables aux autres cas de singularités et ouvrages spéciaux rencontrés en réseau d’assainissement et montrent que : i) les résultats des simulations 3D sont sensibles à la rugosité, aux conditions limites de hauteur et de vitesse ; ii) dans les trois cas d’étude, les schémas de discrétisation du second ordre et l’algorithme de couplage pression/vitesse PISO sont appropriés ; ii) la loi de paroi scalable couplée aux modèles de turbulence de type k-ε pour le cas des jonctions (avec un débit latéral inférieur ou égal au débit principal) ou des déversoirs semblent convenir, tandis que le modèle de turbulence RSM associé à la loi de paroi enhanced ou scalable permet de mieux représenter les écoulements à travers les bifurcations ou au niveau des jonctions lorsque le débit latéral est dominant. Sur la base de ces résultats, une méthodologie de modélisation plus générale définie en six étapes et fondée sur le guide proposée par Jakeman et al. (2006) a été mise au point. La méthodologie ainsi définie a été utilisée pour i) améliorer l’instrumentation du déversoir OTHU (Observatoire de Terrain en Hydrologie Urbaine) situé à Ecully, à partir de la simulation de sa courbe de fonctionnement et en fournissant les incertitudes sur les débits déversés obtenus ; ii) simuler l’implémentation des capteurs débitmétriques à l’aval d’une jonction. Elle a permis de concevoir et de dimensionner un nouveau dispositif de maîtrise des flux d’eau et de polluants déversés (technologie DSM – dispositif de surveillance et de maîtrise des flux déversés au milieu naturel). Ce dispositif a fait l’objet d’un dépôt de brevet international. Enfin, la mise en œuvre de cette méthodologie a été à l’origine de la découverte d’une nouvelle structure d’écoulement dans la branche latérale d’une bifurcation à 90°. L’analyse des résultats des simulations des écoulements mettant en évidence cette nouvelle structure a montré qu’il était possible de prédire l’apparition de cette dernière à partir du rapport d’aspect et du nombre de FroudeThe understanding of sewer flows behaviour is a key component for better urban drainage monitoring and management. However, these flows are conveyed across singularities (such as bends, drops, deviations, etc.) and special structures (combined sewer overflows –CSOs–, channels junction, dividing flow structures, etc.). These singularities and specific structures exhibit complex geometries, leading to open channel turbulent, three-dimensional and multiphase (pollutants and storm and sewer waters) flows. Using three-dimensional CFD (Computational Fluid Dynamics) platform allows a better understanding of mechanisms of contaminants transport through these structures and singularities, leading to a better sewer monitoring. In this thesis, 3D-RANS (Reynolds Averaged Navier Stokes) modelling approach under steady-state conditions is used in order to study flows within CSOs, junctions and bifurcations. Through these three structures, several modelling strategies (wall law/turbulence model combination, velocity/pressure coupling algorithm, spatial discretisation schemes, boundary conditions, computational mesh –shape and size of cells–, etc.) are tested and evaluated thanks to performance indicators (such as RMS –Root Mean Square– indicators) based on velocities (in situ mean velocities and PIV velocity fields obtained in laboratory), water depths and discharge (discharge repartition for bifurcation in laboratory or in situ overflow discharge, for CSOs). Results deriving from these tests are transposable to other singularities or special structures encountered in sewer network and suggest that: i) simulated CFD results are sensitive to the roughness coefficient; ii) for the three studied structures, second-order discretisation schemes and SIMPLE or PISO velocity/pressure coupling algorithm are appropriate; iii) scalable wall function associated to the group of k-ε turbulence model for junction flows (with a lateral inflow lower or equal to the main inflow) or for CSOs is appropriate, whereas RSM turbulence model associated to enhanced wall function allows a better representation of bifurcation flows or junctions flows when the lateral inflow is greater than the main inflow. Based on these results and on Jakeman et al. (2006) guideline, a six steps-methodology focused on the using of RANS approach modelling has been proposed. This six steps-methodology is used in order to i) enhance the monitoring of an OTHU (Observatoire de Terrain en Hydrologie Urbaine) CSO located at Ecully accounting for uncertainties on overflow discharge values ;ii) simulate the performance of flowmeters downstream of a junction, defining the best location for these sensors. This methodology is used to design the new overflow discharge measurement device. This device is an international patent. Finally, the application of the methodology led to point out a new flow structure, occurring in the downstream lateral branch of a 90° bifurcation
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Longo, Riccardo. "Advanced turbulence models for the simulation of air pollutants dispersion in urban area." Doctoral thesis, Universite Libre de Bruxelles, 2020. https://dipot.ulb.ac.be/dspace/bitstream/2013/312254/3/thesis.pdf.
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NOWADAYS, a number of studies keep on demonstrating the existence of a strong relation between high concentrations of particulate matter (PM) and the prevalence of human morbidity and mortality. Large particles can be filtered in the nose or in the throat, while fine particles (about10 micrometer) can settle in the bronchi and lungs, leading to more serious consequences. According to Karagulian et al. the major sources of urban air pollution are traffic (25%), combustion and agriculture (22%), domestic fuel burning (20%), natural dust (18%) and industrial activities (15%).As a consequence, the detailed study of dispersion phenomena within the urban canopy becomes a target of great interest. To this end, Computational Fluid Dynamics (CFD) can be successfully employed to predict turbulence and dispersion patterns, accounting for a detailed characterization of the pollutant sources, complex obstacles and atmospheric stability classes.Despite being intrinsically different phenomena, turbulence and dispersion are closely related. It is universally accepted that, to reach accurate prediction of the concentration field, it is necessary to properly reproduce the turbulence one. For this reason, the present PhD thesis is split into two main Sections: one focused on turbulence modelling and the subsequent, centered on the dispersion modelling.Thanks to its good compromise between accuracy of results and calculation time, Reynolds-averaged Navier-Stokes (RANS) still represents a valid alternative to more resource-demanding methods. However, focusing on the models’ performance in urban studies, Large Eddy Simulation (LES) generally outperforms RANS results, even if the former is at least one order of magnitude more expensive. Stemming from this consideration, the aim of this work is to propose a variety of approaches meant to solve some of the major limitations linked to standard RANS simulation and to further improve its accuracy in disturbed flow fields, without renouncing to its intrinsic feasibility. The proposed models are suitable for the urban context, being capable of automatically switching from a formulation proper for undisturbed flow fields to one suitable for disturbed areas. For neutral homogeneous atmospheric boundary layer (ABL), a comprehensive approach is adopted, solving the issue of the erroneous stream-wise gradients affecting the turbulent profiles and able to correctly represent the various roughness elements. Around obstacles, more performing closures are employed. The transition between the two treatments is achieved through the definition of a Building Influence Area (BIA). The finalgoal is to offer more affordable alternatives to LES simulations without sacrificing a good grade of accuracy.Focusing on the dispersion modelling framework, there exists a number of parameters which have to be properly specified. In particular, the definition of the turbulent Schmidt number Sct, expressing the ratio of turbulent viscosity to turbulent mass diffusivity, is imperative. Despite its relevance, the literature does not report a clear guideline on the definition of this quantity. Nevertheless, the importance of Sct with respect to dispersion is undoubted and further demonstrated in the works of different authors. For atmospheric boundary layer flows, typical constant values range between 0.2 and 1.3. As a matter of fact, the local variability of Sct is supported by experimental evidence and by direct numerical simulations (DNS). These observations further suggest that the turbulent Schmidt number should be prescribed as a dynamic variable. Following these observations a variable turbulent Schmidt number formulation is proposed in this work. The latter stems from the same hypothesis of the variable formulation developed by Gorlé et al. Moreover, the relevant uncertain model parameters are optimized through uncertainty quantification (UQ). This formulation further increased the accuracy of the predictions, and was successfully verified by Di Bernardino et al. However, the turbulent Schmidt number resulting from this formulation is still intrinsically linked to the turbulence model employed, i.e. to the Cμ coefficient. To overcome this constraint, the nature and the dependencies of Sct were further analyzed through correlation studies and employing principal component analysis (PCA) on data obtained through the proposed ABL RANS model. Subsequently, the same data-driven technique was employed based on the high-fidelity outcomes of a delayed Detached Eddy Simulation (dDES) to derive a generalized turbulentSchmidt number formulation. The latter can be employed within a wide range of turbulence models, without limiting its variability.Doctorat en Sciences de l'ingénieur et technologie
info:eu-repo/semantics/nonPublished
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Lewy, Michael Robert. "The Indecomposables of Rank 3 Permutation Modules." Thesis, 1985. https://thesis.library.caltech.edu/11351/1/Lewy_MR_1985.pdf.
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Transitive permutation groups of finite order are viewed as linear groups over fields of characteristic p > 0 by having the group permute the basis elemerits of a vector space M. The decomposition of M into the direct sum of invariant subspaces is investigated, and criteria given for whether M is decomposable, and if it is, how many direct summands occur, in the special case the group has rank 3, i.e., it has 3 orbits on ordered pairs of points. In the case that each orbit is self-paired, M decomposes into the maximum possible number of indecomposables, and the group has every p'-element conjugate to its inverse, irreducibility results are obtained for the indecomposables. This last result holds for any rank. It applies in particular to the symmetric and thence to the alternating groups, which enables us to describe certain modular irreducibles of these groups.
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Wen, Xin. "Higher-rank Transmit Beamforming Using Space Time Block Coding." Phd thesis, 2016. https://tuprints.ulb.tu-darmstadt.de/5464/3/PhD_Thesis_Xin_Wen.pdf.
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With the rapid development of wireless communications, there has been a massive growth in the number of wireless communications users and progressively more new high data rate wireless services will emerge. With these developments taking place, wireless spectral resources are becoming much more scarce and precious. As a result, research on spectrally efficient transmission techniques for current and future communication networks attracts considerable interest. As a promising multi-antenna communication technique, transmit beamforming is widely recognized as being able to improve the capacity of wireless systems without requiring additional spectral resources. In conventional (rank-one) beamforming, each user is served by a single beamformer. For certain transmit beamforming applications, the beamforming performance may be poor if the degrees of freedom in the conventional beamformer design become insufficient.
The scope of this thesis is to address the beamforming performance degradation problems induced by the insufficient degrees of freedom in the beamformer design in certain practical scenarios. In this thesis, a fundamentally new idea of higher-rank (>1) transmit beamforming is proposed to improve the beamforming performance. Instead of a single beamformer assigned to each user, multiple beamformers are designed and correspondingly the degrees of freedom in the beamformer design are multiplied, i.e., the increase of the degrees of freedom consists in the increase of the number of design variables. To implement higher-rank beamforming, the central idea is to combine beamforming with different space time block coding (STBC) techniques. Conventionally, STBCs are used to exploit the transmit diversity resulting from the independent fading for different transmit antennas. However, the use of STBCs in the higher-rank beamforming approaches is not for the sake of transmit diversity, but for the sake of design diversity in the sense of degrees of freedom in the beamformer design.
The single-group multicast beamforming problem of broadcasting the same information to all users is firstly considered in the thesis. It is assumed that the transmitter knows the instantaneous channel state information (CSI) which describes the short-term channel conditions of a communication link and can be estimated in modern communication systems. In the conventional approach, a single beamforming weight vector is designed to steer the common information to all users. In the case of a large number of users, the performance of the conventional approach usually degrades severely due to the limited degrees of freedom offered by a single beamformer. In order to mitigate this drawback, a rank-two beamforming approach is proposed in which two independent beamforming weight vectors are designed. In the rank-two beamforming approach, single-group multicast beamforming is combined with the two dimentional Alamouti STBC, and each user is simultaneously served with two Alamouti coded symbols from two beamformers. The degrees of freedom in the beamformer design are doubled and significant performance improvement is achieved.
The multi-group multicast beamforming problem of transmitting the same information to users in the same group while transmitting independent information to users in different groups, is studied next in the thesis, also assuming that instantaneous CSI is available at the transmitter. The rank-two beamforming approach, originally devised for single-group multicasting networks that are free of multiuser interference, is extended to multi-group multicasting networks, where multiuser interference represents a major challenge. By combining multi-group multicast beamforming with Alamouti STBC, two independent beamforming weight vectors are assigned to each user and the degrees of freedom in the beamformer design are doubled resulting in drastically improved beamforming performance.
Then, the multiuser downlink beamforming problem of delivering independent information to different users with additional shaping constraints is investigated in the thesis, also assuming instantaneous CSI at the transmitter. Additional shaping constraints are used to incorporate a variety of requirements in diverse applications. When the number of shaping constraints is large, the degrees of freedom in the beamformer design can be rather deficient. In order to address this problem, a general rank beamforming approach is proposed in which multiuser downlink beamforming is combined with high dimensional (>2) real-valued orthogonal space time block coding (OSTBC). In the general rank beamforming approach, the number of beamforming weight vectors for each user and the associated degrees of freedom in the beamformer design are multiplied by up to eight times, which lead to significantly increased flexibility for the beamformer design.
Since instantaneous CSI can be difficult to acquire in certain scenarios, the use of statistical CSI describing the long-term statistical characteristics of the channel can be more practical in these scenarios. The rank-two beamformer designs based on instantaneous CSI can be straightforwardly applied in the case of statistical CSI. However, it is impossible to extend the general rank beamforming approach for the multiuser downlink beamforming problem with additional shaping constraints based on instantaneous CSI to the case of statistical CSI straightforwardly. Therefore, multiuser downlink beamforming with additional shaping constraints using statistical CSI at the transmitter is then studied and an alternative general rank beamforming approach is proposed in the thesis. In the general rank beamforming approach using statistical CSI, multiuser downlink beamforming is combined with quasi-orthogonal space time block coding (QOSTBC). The increased number of beamforming weight vectors and the associated degrees of freedom are much beyond the limits that can be achieved by Alamouti STBC in the beamformer design.
Simulation results demonstrate that the proposed higher-rank transmit beamforming approaches can achieve significantly improved performance as compared to the existing approaches.
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Gunturi, Padma. "SpaceView : a visualization tool for matroids of rank at most 3 /." 2002. http://emp3.hbg.psu.edu/theses/available/etd-05142002-134534/.
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Chen, Ya-Chi, and 陳雅琦. "The Analysis of Strategies for the First 3 Rank Women’s Taekwondo." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/85736873645839606232.
Full textAbstract:
碩士國立臺灣師範大學
體育學系在職進修碩士班
102
The purpose of this study was to analyze the strategies for the final fours of the first 3 rank women’s Taekwondo Tournament in the 2013 National Athletic Games. The strategies were divided into attack styles, main attack techniques, active and passive attacks, score counts and successful rate. In every three-round game, it also had a comprehensive description about the attack counts, score counts and successful rate by the attack of active and passive, left foot and right foot, front foot and rear foot, and 8 attack actions. The video observational system was used to record attack techniques; the games were video-recorded during the matches for the analysis. All the variables were tested by χ2nonparametric statistical test and the post-hoc comparison werecalculated by SPSS 21.0, the significant levels as α= .05. The collected data were processed through quantitative analysis and the results are as followed：(1) The attack type of each rank was the active attack style. The frequently-used legs were in the order from front right, front left, rear right to rear left. The highest score successful rate was 13%. (2) There were significant differences in attack actions and frequently-used legs among the participants of different ranks. The round kick was the main attack technique to attack and score, and then the side kicks. The right foot had the highest attack count. (3) No difference was found in the gold medal winners’ attack styles, which were all active attacks. The timesof attack movements with the round kicks rated the highest, and then the side kicks. The single middle attack was performed as major attack type, and the turning kick had the highest successful rate。The findings of this study provided information to understand the strategic techniques appliedin the women's Taekwondo tournament. It could be used as a reference for the training of women athletes.
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Chuang, Jiun-Yau, and 莊鈞堯. "DEAHP cross-efficiency model based on rank reversal: An application to layout planning of Taoyuan International Airport Terminal 3." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/ne5y2f.
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碩士國立臺灣海洋大學
運輸科學系
105
In the past, people usually used a single criterion to make a decision, but they can only solve the relatively simple problem. However, it is full of composite problem in present, so it must give different weights in different criteria when Multi Criteria Decision Method (MCDM) is used to assess decision-making schemes. In many decision-making methods, there are many ways to rank the pros and cons of the alternatives. In the process, the concept of hierarchy is used to calculate weight of each alternative. AHP(Analytic Hierarchy Process)has been one of method that be used widely. There are three purpose of AHP: systematizing complex problems, resolving criteria for different hierarchies and decreasing decision error. The evaluation method compares alternatives or criteria, gets score to calculate weight, and then ranks alternatives. In MCDM, Ramanathan (2006)have used DEA to evaluate weight of AHP, called DEAHP, but there are some drawbacks. For example, the multiplier could be zero, and the result confined to self- evaluation. Afterwards, Wang et al. (2008) used the concept of assurance region (AR) to resolve multiplier problem, but self-evaluation wasn’t resolved. Lee (2016) used DEAHP cross-efficiency method to solve these two main drawbacks. In addition, rank reversal is always a controversial problem when AHP is used to evaluate alternatives. Hence, in order to obtain the discriminative and persuasive results, this research considers this problem. In empirical analysis, this research evaluates the layout planning of Taoyuan International Airport Terminal 3 under construction. This research uses the importance of facility placement to rank the three shortlisted alternatives. Next, under the consideration of the problem of rank reversal, a dummy alternative (alternative 4) which is not announced is added to explore whether the weight of alternative is varied or not.
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Yu-Wen, Tsai, and 蔡友文. "The Analysis of Strategies for the first 3 rank Girls’ Taekwondo Tournament in 2008 National High School Athletic Games." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/8c88qg.
Full textAbstract:
碩士國立臺灣師範大學
體育學系在職進修碩士班
96
The Analysis of Strategies for the first 3 rank Girls’ Taekwondo Tournament in 2008 National High School Athletic Games Master’s thesis, June, 2008 Tsai Yu-Wen Advisor: Keh Nyit Chin, Ph. D. Abstract The purpose of this study was to analyze the strategies for the first 3 rank Girls’ Taekwondo Tournament in 2008 National High School Athletic Games. The participants were the final fours of the first 3 ranks’ Taekwondo Tournament in 2008 National High School Athletic Games. The games were video-recorded during the matches for further analysis. The analysis focused on the strategic movement patterns of participants’ attack patterns, attack movement, prefer leg and scoring average; the differences of attack patterns, attack movements, prefer leg, feigning movements, times of fouls and the scoring among the participants of different ranks in different rounds. There were 3 main results as follows: (1) The attack patterns of all the ranks were active attacks. The attack movements were mainly roundhouse kicks and the downward kicks. The prefer leg used were in the order from rear right, front left, rear left to front right . The highest scoring average belonged to the downward kicks which was13.7%. (2) The attack patterns of the participants of different ranks were active attacks. There were significant differences in their attack movements and prefer leg. There were also differences in their use of feigning movements and times of fouls. However, no difference in their scoring was found. (3) No difference was found in their attack patterns of the participants in different rounds. The attack movements were all active attacks. No difference in their times of attack movements with the roundhouse kicks rated the highest. Their prefer legs were mainly rear right and front left. No difference between the participants’ feigning movements, times of fouls and scoring. The findings of this study provided information to understand the strategic techniques applied in the high school girls’ Taekwondo tournament. It could be used as a reference for the training of school teams, so as to promote the quality of the country’s Taekwondo standards. key words: Taekwondo, attack patterns, feigning movements
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Zheng, Zhaohui. "A regression framework for learning to rank in web information retrieval." 2008. http://proquest.umi.com/pqdweb?did=1594491171&sid=3&Fmt=2&clientId=39334&RQT=309&VName=PQD.
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Thesis (Ph.D.)--State University of New York at Buffalo, 2008.Title from PDF title page (viewed on Jan. 29, 2009) Available through UMI ProQuest Digital Dissertations. Thesis adviser: Srihari, Rohini K. Includes bibliographical references.
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LIN, BING-YUAN, and 林炳源. "Analysis of 3'-terminal nucleotide sequences of cucumber mosaic virus NT9 RANs." Thesis, 1990. http://ndltd.ncl.edu.tw/handle/43523747097153442176.
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Janelle-Montcalm, Audrée. "Dualité d'action de la galectine-3 dans la pathophysiologie de l'arthrose." Thèse, 2007. http://hdl.handle.net/1866/15416.
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Dutta, Usha Rani [Verfasser]. "Molecular characterization of a pericentric inversion of chromosome 3 in a 3-generation family with short stature / von Dutta Usha Rani." 2008. http://d-nb.info/994457936/34.
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Yu-HsuanMei and 梅育瑄. "A 3-D RANS Simulation of Tsunami Propagation Induced by Large-Scale Underwater Landslide." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/868zvn.
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碩士國立成功大學
土木工程學系
105
By means of the finite element code FLOW-3D, the tsunami propagation induced by a large-scale submarine landslide is studied numerically. The landslide is assumed to take place by the collapse of Keelung Islet, which locates on the northeast coast of Taiwan. Using the energy equivalence principle, four densities of the collapse are considered: 3000kg/m3, 6000kg/m3, 9000kg/m3, 12000kg/m3. Because of a sudden vertical displacement of the ocean's surface, when the collapse falls into water, it would induce the tsunami propagation, and the tsunami waves will travel to the shore of the Jinshan Nuclear Power Plant (1st Nuclear Power Plant) and Kuosheng Nuclear Power Plant (2nd Nuclear Power Plant). According to the analysis results, the highest wave height will occur at 2nd or 3rd wave whether it occurs at the 1st or 2nd Nuclear Power Plant. The highest wave height at the 1st Nuclear Power Plant reaches 0.38 metres, and it reaches 2.1 metres at the 2nd Nuclear Power Plant. Due to natural topography in nearshore region of the 2nd Nuclear Power Plant, the waves will inundate and thus needing to construct a seawall to protect the nearshore region and reduce hazards.
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Pereira, dos Santos Silva Marcela. "Projet pour l'amélioration de la performance des entreprises aéronautiques de rang 2 et 3." Thèse, 2017. http://depot-e.uqtr.ca/8067/1/031624521.pdf.
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"The role of Ran-binding protein 3 during influenza A virus replication." Thesis, 2014. http://hdl.handle.net/10388/ETD-2014-04-1526.
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Influenza A virus (family Orthomyxoviridae) is one of the most important human pathogens, causing annual epidemics with significant worldwide mortality, and sporadic but potentially devastating pandemics. The influenza A viral genome encodes 14 proteins and consists of 8 segments of negative-stranded RNA. During infection, the virus exploits the host cell signaling machinery to ensure efficient replication. The PI3K/Akt and Ras/ERK are two of the signaling cascades that are induced for virus survival.
Influenza A virus replicates in the nucleus, hence the newly synthesized RNPs must be exported from the nucleus and exported to the cell membrane. Although the detailed mechanism of vRNP nuclear export is not yet fully elucidated, several studies on this process have begun to emerge. Influenza A virus nucleoprotein nuclear export is CRM1-dependent. Ran-binding protein 3 (RanBP3) is a Ran-interacting protein that is best known for its role as a cofactor of CRM1-mediated cargo nuclear export. In this study, we investigated the role of RanBP3 during the influenza A virus life cycle. We found that RanBP3 was phosphorylated at Ser58 in early and late phases of infection. Knockdown of RanBP3 expression led to a vRNP nuclear retention, suggesting that RanBP3 is involved in vRNP nuclear export. Moreover, we demonstrated that RanBP3’s function during vRNP nuclear export is regulated by phosphorylation at Ser58, and the RanBP3 phosphorylation is modulated by both PI3K/Akt and Ras/ERK/RSK pathways in the late phase of viral infection. In conclusion, this study has shown that RanBP3 is a host factor that has a vital role during the late stage of influenza A virus replication, specifically as a co-factor in CRM1-mediated nuclear export. Identifying this host factor will contribute to the understanding of the mechanism of vRNP transport.
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Chiu, Pin-Wen, and 邱品文. "The Inhibitory Effect of Vt-A-3-2, a Stilbene Isolated from Vitis thunbergii, on RANKL-Induced Osteoclastogenesis." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/39010439150235390017.
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碩士國立陽明大學
藥理學研究所
99
Vt-A-3-2 is a stilbene isolated from the root of Vitis thunbergii. This study was conducted in receptor activator of nuclear factor kappa-B ligand (RANKL)-activated RAW264.7 cells to access the effect of Vt-A-3-2 on osteoclastogenesis and elucidate the mechanisms of action. The results showed that Vt-A-3-2 concentration (10, 20, and 30μM)-dependently inhibited RANKL-induced osteoclastic differentiation in RAW 264.7 cells demonstrated by increase in tartrate-resistant acid phosphatase (TRAP) activity with an IC50 value of 18.4 μM , but without significant cytotoxicity. NF-κB and c-Fos are key transcription factors to up-regulate nuclear factor of activated T cells c1 (NFATc1) expression for osteoclastogenesis by RANKL. In the presence of Vt-A-3-2, RANKL-triggered nuclear translocations of NF-κB and c-Fos as well as associated induction and nuclear accumulation of NFATc1 were all prominently abrogated. Further, the upstream IKK phosphorylation, IκB degradation and MAPKs (ERK, JNK and p38) phosphorylations were substantially repressed by Vt-A-3-2. On the other hand, RANKL-evoked induction of c-Fos and NF-κB expression were attenuated by Vt-A-3-2 treatment. Exposure of RAW 264.7 cells to RANKL up-regulated MMP-9 gelatinolytic activity and resulted in bone resorption, such responsiveness were obviously repressed by concurrent, but moderately attenuated by subsequent addition of Vt-A-3-2. In conclusion, the anti-osteoclastogenic mechanisms of Vt-A-3-2 might cause by interfering with IKK/IκB mediated NF-κB and MAPKs mediated c-Fos activation pathways to repress NFATc1 activation and MMP-9 expression essential for bone resorption. These results suggested that Vt-A-3-2 might be beneficial for the prevention or treatment of catabolic bone diseases.
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Ryšavá, Jitka. "Dítě mladší 3 let v mateřské škole." Master's thesis, 2012. http://www.nusl.cz/ntk/nusl-305552.
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RYŠAVÁ, J. A child under 3 years of age at preschool. Prague, 2012. The thesis. Charles University in Prague. Faculty of Education. Department of Primary Education. Thesis supervisor E. Opravilová. The work followed the specifics of the educational work between 2-3 years of age in an ordinary preschool. The theoretical part is based on developmental psychological characteristics of this period. It monitored the impact of early interactions mother - child, influence of family environment and other factors affecting the child's separation from the mother and the subsequent adaptation and socialization in a preschool environment. The survey includes six case studies of selected two-year old children (position of the child), 24 selected parents of preschool children within one preschool (parents' position) and 51 preschools (teacher's position). The research followed the specific impact of key factors influencing the course of adaptation and socialization of a child under 3 years of age in a preschool environment, including the anticipated impact of key chronological age. In addition, it monitored and defined the conditions of preschools in the legislative, organizational and personnel conditions, and when their fulfillment can be considered suitable for education of a child under 3 years in a...
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Βάλβης, Εμμανουήλ. "Μια νέα διάταξη ασαφών αριθμών και η στοχαστική της επέκταση σε ελέγχους ασαφών υποθέσεων." Thesis, 2013. http://hdl.handle.net/10889/6600.
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Η παρούσα διατριβή εκπονήθηκε με σκοπό να γενικεύσει το πρόβλημα του ελέγχου υποθέσεων που εμπεριέχουν στοχαστική διάταξη στα πλαίσια της Μη Παραμετρικής Στατιστικής. Για τον σκοπό αυτό μελετήθηκε η σχετική βιβλιογραφία, εξετάσθηκε η ορολογία, οι ήδη υπάρχοντες ορισμοί και οι σχετικές προταθείσες μέθοδοι και ακολούθως έγινε προσπάθεια γενίκευσης του προαναφερθέντος προβλήματος. Η έρευνα αυτή απέδωσε δύο ομάδες αποτελεσμάτων. Στην πρώτη, ορίσθηκε μια νέα ολική διάταξη (XFO) σε κάθε σύνολο ασαφών αριθμών που έχουν διαφορετικές κορυφές οι οποίες σχηματίζουν συμπαγές υποσύνολο του ℝ. Η ασαφής αυτή διάταξη αποδίδει την σύγκριση των ασαφών αριθμών με ένα ασαφές μέτρο αναγκαιότητας και με το δυϊκό του μέτρο δυνατότητας. Η σύγκριση αυτής της μεθόδου με την πλέον αναγνωρισμένη αντίστοιχη μέθοδο διάταξης ασαφών αριθμών απέδειξε ότι η εισαχθείσα μέθοδος XFO είναι πιο κοντά στην αρχική μας εκτίμηση για την διάταξη και ανταποκρίνεται πιο αισιόδοξα. Στην δεύτερη ομάδα αποτελεσμάτων εισάγεται η έννοια της στοχαστικής διάταξης ασαφών τυχαίων μεταβλητών, με σύντηξη των ακολούθων εννοιών:
α) της στοχαστικής διάταξης,
β) της ανωτέρω ασαφούς διάταξης και
γ) της εισαγόμενης έννοιας της ασαφούς συνάρτησης κατανομής.
Ο ορισμός της στοχαστικής διάταξης δίδεται σε αρμονία με την μέθοδο XFO, αφού και οι δύο έχουν τις ρίζες τους στην ίδια διάταξη κλειστών διαστημάτων που εισάγεται αρχικά στην εργασία, μπορεί δε να θεωρηθεί η ασαφής στοχαστική διάταξη ως επέκταση της XFO. Η δεύτερη αυτή ομάδα περιλαμβάνει ένα εισαγόμενο για πρώτη φορά τρόπο ορισμού Ασαφών Υποθέσεων που περιέχουν στοχαστική διάταξη ασαφών τυχαίων μεταβλητών. Αυτό έχει αποτέλεσμα να βαθμολογείται θετικά μόνο η μία εκ των δύο ασαφών υποθέσεων, ασαφούς μηδενικής και ασαφούς εναλλακτικής, διευκολύνοντας έτσι την λήψη αποφάσεων. Προτείνεται διαδικασία ασαφούς ελέγχου που πιστοποιεί οποιαδήποτε ενυπάρχουσα στοχαστική διάταξη δύο ασαφών τυχαίων δειγμάτων, συμβατή με τον ορισμό, η οποία αντιστοιχεί θετικές τιμές αλήθειας μόνον στην αποδεκτή υπόθεση και μηδέν στην απορριπτόμενη. Τα αποτελέσματα του ελέγχου εκφράζονται με την βοήθεια δύο μέτρων αναγκαιότητας. Η μείζων συνεισφορά της προτεινόμενης ασαφούς διαδικασίας ελέγχου ασαφών υποθέσεων, που αναφέρονται σε στοχαστική διάταξη ασαφών τυχαίων μεταβλητών, είναι ότι παρέχει εργαλείο μετασχηματισμού του προβλήματος σε ένα περιορισμένο αριθμό ελέγχων κλασσικών υποθέσεων της μη Παραμετρικής Στατιστικής. Με τον τρόπο αυτό μπορούμε να συμβάλουμε στην επίλυση τέτοιων προβλημάτων ασαφών ελέγχων τόσο θεωρητικών ζητημάτων στοχαστικής διάταξης ασαφών τυχαίων μεταβλητών όσο και ενός αριθμού πρακτικών προβλημάτων, όπως της ασαφούς αξιολόγησης εξεταζομένων.This dissertation has been carried out in order to extend the problem of testing hypotheses on stochastic orderings, with methods based on ranks. This study provides two sets of related results. In the first set of results we introduce a novel linear order, the “extended fuzzy order” (XFO), on every subset of F(ℝ), the members of which must have their modal values all different and form a compact subset of ℝ. A distinct new feature is that our linear determined procedure employs the corresponding order of a class interval associated with a confidence measure which assigns a necessity measure value on every comparison . This new XFO method measures the ordering of any two fuzzy numbers with a possibility and a necessity measure, a feature that makes the method relevant for processing of fuzzy statistical data. These fuzzy measures are compared with the widely accepted PD and NSD indices of D. Dubois and H. Prade. The comparison proves that our possibility and necessity measures are more optimistic and comply better with our intuition. In the second set of results it is investigated the fuzzy extension of hypotheses testing using non parametric methods based on ranks. To achieve this, the notion of fuzzy distribution function is introduced in a practical manner, which is proved to be equivalent to the known notion of Kruse and Mayer. The stochastic ordering of two fuzzy random samples is defined in a fusion of the notion of stochastic ordering, fuzzy distribution function and XFO method. A novel definition of fuzzy hypotheses related to a potential fuzzy stochastic order between two fuzzy random samples is given in a new manner so that the null and its alternative hypotheses do not overlap. Consequently, the method assigns positive possibility grades either to the null fuzzy hypothesis or to the its fuzzy alternative. This simplifies the fuzzy decision making, and moreover there is no need to defuzzify the results if a clear cut decision is required. A fuzzy statistical inference procedure of fuzzy hypotheses is proposed and it is carried out at a fuzzy significance level. The definition of a fuzzy critical value is required, which is carried out in a practical manner. The proposed method certifies any underlying stochastic fuzzy order between two fuzzy random samples giving grades of confidence to that. Two necessity measures are assigned to the rejection of the fuzzy null hypothesis in favor of its alternative. The first measures the necessity of the existence of any fuzzy stochastic ordering between the fuzzy random samples under examination. The second necessity measure expresses the confidence of the fuzzy null hypothesis rejection uniformly for all relevant α-cut levels. The main contribution of this thesis, as far as the second set of results is concerned, is that a problem of testing fuzzy hypotheses on stochastic orderings of fuzzy random variables at a fuzzy significance level, is transferred to a limited number of tests of classic hypotheses. These tests are carried out at a fuzzy significance level, and are processed with the application of the linear fuzzy ordering procedure XFO.