To see the other types of publications on this topic, follow the link: Ordre maximal.
Dissertations / Theses on the topic 'Ordre maximal'
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 'Ordre maximal.'
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
Godin, Marjory. "Structure galoisienne d'anneaux entiers." Valenciennes, 2002. https://ged.uphf.fr/nuxeo/site/esupversions/60ddf114-2ffe-40f8-856b-eec83b7256bb.
Full textAbstract:
Soient k un corps de nombres, O son anneau d'entiers et Γ le groupe alterné A₄. On suppose que k et Q(j) sont linéairement disjoints sur Q. Soient M un ordre maximal de O dans l’algèbre semi-simple k[ Γ ] contenant O[ Γ ] et C1(M) son groupe des classes. On désigne par R(M) l’ensemble des classes réalisables, c’est-à-dire l’ensemble des classes c ∈ C1(M) telles qu’il existe une extension galoisienne N/k modérément ramifiée, à groupe de Galois isomorphe à Γ et telle que la classe de M⊗₀Γ soit égale à c, où O est l’anneau des entiers de N. Dans cette thèse nous déterminons effectivement les éléments de R(M) et nous montrons que R(M) est un sous-groupe de C1(M). Lorsque nous essayons d’étudier R(M), nous sommes confrontés au problème de plongement en liaison avec les classes de Steinitz, une autre partie de cette thèse est l’étude des classes de Steinitz d’extensions tétraédrales et nous avons aussi étudié le cas où Γ est le groupe symétrique S₄Let k be a number field, O its ring of integers and Γ the alternating group A₄. Assume that k and Q(j) are linearly disjoint over Q. Let M be a maximal O-order in k[ Γ ] containing O[ Γ ] and C1(M) its classgroup. We denote by R(M) the set of realizable classes, that is, the set of classes c ∈ C1(M) such that there exists a Galois extension N/k with Galois group isomorphic to Γ and the class of M⊗₀Γ equal to c, where O is the ring of integers of N. In this thesis, we determine effectively the elements of R(M) and we prove that R(M) is a subgroup of C1(M). When we try to study R(M), we are confronted with an embedding problem connected with the Steinitz classes, another part of this thesis is the study of Steinitz classes of tetrahedrals extensions and we have study too the case when is the symetric group S₄
2
Huang, Yi. "Théorie des opérateurs sur les espaces de tentes." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS100/document.
Full textAbstract:
Nous donnons un mécanisme de type Calderón-Zygmund concernant la théorie de l’extrapolationpour des opérateurs d’intégrale singulière sur les espaces de tentes. Pour des opérateursde régularité maximale sur les espaces de tentes, nous donnons des résultats optimaux enexploitant la structure des opérateurs intégraux de convolution et en utilisant des estimationsde la décroissance hors-diagonale du semi-groupe ou de la famille résolvante sous-jacente.Nous appliquons des techniques précédentes d’analyse harmonique et fonctionnelle pourestimer sur les espaces de tentes certains opérateurs d’intégrale évolutionnelle, nées de l’étudedes problèmes aux limites elliptiques et des systèmes non-autonomes du premier ordreWe give a Calderón-Zygmund type machinery concerning the extrapolation theory for thesingular integral operators on tent spaces. For maximal regularity operators on tent space, wegive some optimal results by exploiting the structure of convolution integral operators and byusing the off-diagonal decay estimates of the underlying semigroup or resolvent family.We apply the previous harmonic and functional analysis techniques to estimate on tentspaces certain evolutionary integral operators arisen from the study of boundary value ellipticproblems and first order non-autonomous systems
3
Bruche, Clément. "Structure galoisienne relative d'anneaux d'entiers d'extensions non abéliennes." Valenciennes, 2007. http://ged.univ-valenciennes.fr/nuxeo/site/esupversions/aa3c8ae9-3fc8-41e3-bfac-dd5f7159a586.
Full textAbstract:
Soient k un corps de nombres, Ok son anneau d’entiers et Cl(k) son groupe des classes. Soient G un groupe fini, N/k une extension galoisienne à groupe de Galois isomorphe à G et ON l’anneau des entiers de N. Soient M un Ok-ordre maximal dans l’algèbre semi-simple k[G] contenant Ok [G], et Cl(M) son groupe des classes (i. E. , le groupe des classes des M-modules localement libres). Lorsque N/k est modérément ramifiée, l’extension des scalaires permet d’associer à ON la classe de M*ON , notée [M*ON ], dans Cl(M). On définit l’ensemble R(M) des classes réalisables comme étant l’ensemble des classes c de Cl(M) telles qu’il existe une extension N/k modérément ramifiée, à groupe de Galois isomorphe à G, avec [M*ON ] = c. Il est bien connu que R(M) est inclus dans Cl◦ (M), où Cl◦ (M) est le noyau du morphisme de Cl(M) dans Cl(k) induit par l’augmentation de M dans Ok. Les résultats de McCulloh vont dans le sens de la conjecture suivante : R(M) est un sous-groupe de Cl◦ (M). Lorsque G est abélien et k un corps de nombres quelconque, les travaux de McCulloh entraînent que cette conjecture est vraie. Soient p un nombre premier et x une racine primitive p-ième de l’unité. Dans cette thèse, en supposant x dans k, nous démontrons la conjecture dans le cas où G = V*\rhoC, où V est un Fp-espace vectoriel de dimension r ≥ 1, C un groupe cyclique d’ordre p^r − 1, et \rho une représentation linéaire fidèle de C dans V ; un exemple d’un tel groupe est le groupe symetrique S3. Par ailleurs, lorsque nous essayons d’étudier cette conjecture, nous sommes confrontés au problème de plongement en liaison avec les classes de Steinitz. Une autre partie de cette thèse est l’étude des classes de Steinitz des extensions à groupe de Galois isomorphe à V*\rhoC, ou à un groupe non abélien d’ordre p^3Let k be a number field, Ok its ring of integers and Cl(k) its classgroup. Let G be a finite group, N/k a Galois extension with Galois group isomorphic to G, and ON the ring of integers of N. Let M be a maximal Ok -order in the semi-simple algebra k[G] containing Ok[G], and Cl(M) its classgroup (i. E. The classgroup of locally free M-modules). When N/k is tame (i. E. , at most tamely ramified), extension of scalars allows us to assign to ON the class of M*ON , denoted [M*ON ], in Cl(M). We define the set R(M) of realizable classes to be the set of classes c of Cl(M) such that there exists a Galois extension N/k which is tame, with Galois group isomorphic to G, and for which [M*ON ] = c. It is well known that R(M) is included in Cl◦(M), where Cl◦(M) is the kernel of the morphism from Cl(M) to Cl(k) induced by the augmentation from M to Ok. The results of McCulloh lead one to the following conjecture : R(M) is a subgroup of Cl◦(M). If G is abelian and k is any number field, it follows from the works of McCulloh that this conjecture is true. Let p be a prime number and x a primitive p-th root of unity. In this thesis, assuming x in k, we prove the conjecture when G = V*\rhoC, where V is an Fp -vector space of dimension r ≥ 1, C a cyclic group of order p^r −1, and \rho a faithful representation of C in V ; an example is the symmetric group S3. When we attempt to study this conjecture, we are faced with the embedding problem connected with the Steinitz classes. Another part of this thesis is the study of Steinitz classes of extensions with Galois group isomorphic to V*\rhoC, or to a nonabelian group of order p^3. Keywords : Rings of integers, Galois module structure, Realizable classes, Steinitz classes, Maximal order, Fröhlich’s Hom-description of locally free class groups, Fröhlich-Lagrange resolvent, Embedding problem, Cyclic codes, Primitive polynomials
4
McGrath, J. D. "Maximal-#rho#-extensions and irreducibility." Thesis, University of Oxford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235015.
Full text
5
Khalil, Maya. "Classes de Steinitz, codes cycliques de Hamming et classes galoisiennes réalisables d'extensions non abéliennes de degré p³." Thesis, Valenciennes, 2016. http://www.theses.fr/2016VALE0012/document.
Full text
6
Johnston, Michael John. "The physiological response to maximal speed training : influence of session number and order." Thesis, Swansea University, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.678611.
Full text
7
Rigal, Laurent. "Analogues quantiques de l'algebre de weyl et ordres maximaux quantiques." Paris 6, 1996. http://www.theses.fr/1996PA066680.
Full textAbstract:
Dans ce travail, on etudie certaines algebres quantiques et, plus particulierement, deux analogues quantiques de l'algebre de weyl. Dans le premier chapitre, on classifie le spectre premier de l'algebre de weyl quantique de georges maltsiniotis. On en deduit la catenarite et une description explicite du groupe automorphismes de cette algebre. Dans le second chapitre, on demontre un analogue quantique de l'inegalite de bernstein pour un localisation simple de l'algebre de weyl quantique ainsi que pour l'algebre de weyl-hayashi. On etudie les modules holonomes sur ces deux algebres et on etablit une equation fonctionnelle pour certains modules obtenus par localisation du module standard. Dans le troisieme chapitre, on etudie certaines algebres quantiques du point de vue de la propriete d'ordre maximal. On montre que, en situation generique, les quotients premiers de l'algebre de weyl quantique, de l'espace quantique uniparametre et de l'analogue quantique de l'anneau des fonctions regulieres sur les matrices carrees d'ordre deux sont des ordres maximaux de leur corps de fractions. On etudie plus en details le cas des espaces quantiques uniparametres. On rappelle la notion d'anneau noetherien non-commutatif et on montre que certains quotients premiers sont des ordres maximaux sans etre des anneaux factoriels. De plus, on calcule la dimension homologique globale des localises d'un espace quantique uniparametre vis-a-vis de ses cliques d'ideaux premiers.
8
Chaubert, Jérôme. "Minimum euclidien des ordres maximaux dans les algèbres centrales à division /." [S.l.] : [s.n.], 2007. http://library.epfl.ch/theses/?nr=3717.
Full text
9
Fontana, Eleonora. "Maximum Principle for Elliptic and Parabolic Equations." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/12061/.
Full textAbstract:
Nel primo capitolo si riporta il principio del massimo per operatori ellittici. Sarà considerato, in un primo momento, l'operatore di Laplace e, successivamente, gli operatori ellittici del secondo ordine, per i quali si dimostrerà anche il principio del massimo di Hopf. Nel secondo capitolo si affronta il principio del massimo per operatori parabolici e lo si utilizza per dimostrare l'unicità delle soluzioni di problemi ai valori al contorno.
10
Voisei, Mircea Dan. "First-order necessary optimality conditions for nonlinar optimal control problems." Ohio : Ohio University, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1091111473.
Full text
11
Drake, D. H. "A comparison of quality of life, legitimacy and order in two maximum security prisons." Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.598637.
Full textAbstract:
This research is an extensive comparison of two maximum-security prisons in England. Its key aim was to describe the contemporary experience of prisons ‘at the deep end’ of an expanding and deepening penal system. In part, this research revisits and builds on the work of Sparks, Bottoms, and Hay (1996) in Prisons and the Problem of Order, but does so in light of contemporary penelogical developments. It also draws extensively from the work of Leibling (2004) on quality of prison life, but applies her work at the extreme end of imprisonment. This research takes into account both the contemporary and historical context of the two prisons studied. The historical aspect of the research included the study of available documents and interviews with key figures from each prison’s past. The current experience of staff and prisoners in the two prisons studied was investigated primarily using an ethnographic approach. Three months were spent in each prison, interviewing staff and prisoners and observing prison life. In addition, survey data was collected from staff and prisoners at each prison using a revised version of the Measuring Quality of Prison Life survey (Liebling and Arnold 2002). The research found that the repressive environments appeared to outweigh the potential benefits of any rehabilitative opportunities. Although these prisons were quite effective in delivering punishment to prisoners, the more constructive purposes of imprisonment were lacking. Current penal policy in the UK is increasingly punitive and the use of prison sentences and their increasing length means that it is now more important than ever (e.g. in view of the European convention on Human Rights) to keep a close watch on the conditions in which prisoners are spending these sentences.
12
Naujokat, Felix. "Stochastic control in limit order markets." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät II, 2011. http://dx.doi.org/10.18452/16387.
Full textAbstract:
In dieser Dissertation lösen wir eine Klasse stochastischer Kontrollprobleme und konstruieren optimale Handelsstrategien in illiquiden Märkten. In Kapitel 1 betrachten wir einen Investor, der sein Portfolio nahe an einer stochastischen Zielfunktion halten möchte. Gesucht ist eine Strategie (aus aktiven und passiven Orders), die die Abweichung vom Zielportfolio und die Handelskosten minimiert. Wir zeigen Existenz und Eindeutigkeit einer optimalen Strategie. Wir beweisen eine Version des stochastischen Maximumprinzips und leiten damit ein Kriterium für Optimalität mittels einer gekoppelten FBSDE her. Wir beweisen eine zweite Charakterisierung mittels Kauf- und Verkaufregionen. Das Portfolioliquidierungsproblem wird explizit gelöst. In Kapitel 2 verallgemeinern wir die Klasse der zulässigen Strategien auf singuläre Marktorders. Wie zuvor zeigen wir Existenz und Eindeutigkeit einer optimalen Strategie. Im zweiten Schritt beweisen wir eine Version des Maximumprinzips im singulären Fall, die eine notwendige und hinreichende Optimalitätsbedingung liefert. Daraus leiten wir eine weitere Charakterisierung mittels Kauf-, Verkaufs- und Nichthandelsregionen ab. Wir zeigen, dass Marktorders nur benutzt werden, wenn der Spread klein genug ist. Wir schließen dieses Kapitel mit einer Fallstudie über Portfolioliquidierung ab. Das dritte Kapitel thematisiert Marktmanipulation in illiquiden Märkten. Wenn Transaktionen einen Einfluß auf den Aktienpreis haben, dann können Optionsbesitzer damit den Wert ihres Portfolios beeinflussen. Wir betrachten mehrere Agenten, die europäische Derivate halten und den Preis des zugrundeliegenden Wertpapiers beeinflussen. Wir beschränken uns auf risikoneutrale und CARA-Investoren und zeigen die Existenz eines eindeutigen Gleichgewichts, das wir mittels eines gekoppelten Systems nichtlinearer PDEs charakterisieren. Abschließend geben wir Bedingungen an, wie diese Art von Marktmanipulation verhindert werden kann.In this thesis we study a class of stochastic control problems and analyse optimal trading strategies in limit order markets. The first chapter addresses the problem of curve following. We consider an investor who wants to keep his stock holdings close to a stochastic target function. We construct the optimal strategy (comprising market and passive orders) which balances the penalty for deviating and the cost of trading. We first prove existence and uniqueness of an optimal control. The optimal trading strategy is then characterised in terms of the solution to a coupled FBSDE involving jumps via a stochastic maximum principle. We give a second characterisation in terms of buy and sell regions. The application of portfolio liquidation is studied in detail. In the second chapter, we extend our results to singular market orders using techniques of singular stochastic control. We first show existence and uniqueness of an optimal control. We then derive a version of the stochastic maximum principle which yields a characterisation of the optimal trading strategy in terms of a nonstandard coupled FBSDE. We show that the optimal control can be characterised via buy, sell and no-trade regions. We describe precisely when it is optimal to cross the bid ask spread. We also show that the controlled system can be described in terms of a reflected BSDE. As an application, we solve the portfolio liquidation problem with passive orders. When markets are illiquid, option holders may have an incentive to increase their portfolio value by using their impact on the dynamics of the underlying. In Chapter 3, we consider a model with competing players that hold European options and whose trading has an impact on the price of the underlying. We establish existence and uniqueness of equilibrium results and show that the equilibrium dynamics can be characterised in terms of a coupled system of non-linear PDEs. Finally, we show how market manipulation can be reduced.
13
Simonsen, Ola. "Stock data, trade durations, and limit order book information." Doctoral thesis, Umeå : Department of Economics, Umeå University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-839.
Full text
14
Naftali, Eran 1971. "First order bias and second order variance of the Maximum Likelihood Estimator with application to multivariate Gaussian data and time delay and Doppler shift estimation." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/88334.
Full text
15
Uffelmann, Ingo [Verfasser], and Wolfgang [Akademischer Betreuer] Knapp. "Strongly constrained maximal subgroups and Sims order bounds for finite almost simple linear and unitary groups / Ingo Udo Karl Wilhelm Uffelmann ; Betreuer: Wolfgang Knapp." Tübingen : Universitätsbibliothek Tübingen, 2017. http://d-nb.info/1199546224/34.
Full text
16
LEJEUNE, BERNARD. "Modèles à erreurs composées et hétérogénéité variable : modélisation, estimation par pseudo-maximum de vraisemblance au deuxième ordre et tests de spécification." Paris 12, 1998. http://www.theses.fr/1998PA122007.
Full textAbstract:
Cette these est consacree a l'etude de quelques problemes econometriques associes a la modelisation de l'heterogeneite des comportements individuels lorsque l'on travaille avec des donnees micro-economiques en panel. Elle poursuit un double objectif : d'une part, proposer et discuter une extension du modele a erreurs composees standard permettant de prendre en compte et de rendre compte de phenomenes d'heterogeneite individuelle variables, et d'autre part, fournir pour l'estimation et la mise a l'epreuve de la specification du modele propose un ensemble coherent de procedures d'estimation et de tests prenant explicitement en compte une possible mauvaise specification de la forme d'heterogeneite modelisee. La these est composee de quatre chapitres. Dans un cadre qui depasse largement - mais inclut comme cas particulier - les modeles a erreurs composees, le premier chapitre etablit les conditions sous lesquelles les estimateurs de type pseudo-maximum de vraisemblance au deuxieme ordre d'un modele semi-parametrique a l'ordre 2 sont robustes a une mauvaise specification de la variance conditionnelle, et etudie leurs proprietes asymptotiques. Dans le meme cadre general que le chapitre 1, le second chapitre decrit comment, a partir d'un tel estimateur, tirer parti de l'approche 'm-test' pour tester de maniere extensive, avec ou sans hypothese alternative clairement definie, la specification des modeles semi- parametriques a l'ordre 2. Le troisieme chapitre expose et discute l'extension proposee du modele a erreurs composees standard et montre, en s'appuyant sur les resultats theoriques generaux des deux premiers chapitres, comment estimer et tester de facon robuste ce modele. Finalement, le quatrieme chapitre illustre l'interet pratique des resultats degages. Cette illustration, qui consiste en l'estimation et le test de la specification de fonctions de production, est basee sur un panel incomplet de 824 entreprises francaises observees sur la periode 1979-1988 (5201 observations)This thesis considers some econometric issues associated with the modelisation of the heterogeneity of individual behaviors when working with microeconomic panel data. Its purpose is twofold. First, to propose and discuss an extension of the standard error components model which allows to take into account and account for phenomenons of variable heterogeneity. Second, to provide, for its estimation and specification testing, a set of integrated inferential procedures taking explicitly into account a possible misspecification of the assumed form of heterogeneity. The thesis is composed of four chapters. In a very general framework which includes error components models as a special case, chapter 1 establishes the conditions under which second order pseudo-maximum likelihood estimators of a second order semi-parametric model are robust to conditional variance misspecification, and investigates their asymptotic properties. Remaining in the same general framework than chapter 1, chapter 2 describes how, from such a robust estimator, to take advantage of the 'm-testing' approach to extensively test, with or without explicit alternative, the specification of second order semi-parametric models. Chapter 3 exposes and discusses the proposed extension of the standard error components model and, using the general results obtained in the first two chapters, shows how to estimate and test this model in a robust way. Finally, chapter 4 illustrates the practical usefulness of the provided results. This illustration consists in production functions estimation and specification testing, and is based on an incomplete panel dataset of 824 french firms observed over the period 1979-1988 (5201 observations)
17
Young, Alexander L., and Alexander L. Young. "Three Essays on Complex Systems: Self-Sorting in a One-Dimensional Gas, Collective Motion in a Two-Dimensional Ensemble of Disks, and Environment-Driven Seasonality of Mosquito Abundance." Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/624567.
Full textAbstract:
Complex systems offer broad, unique research challenges due to their inability to be understood through a classic reductionist perspective, as they exhibit emergent phenomena that arise through the interactions of their components. In this thesis, we briefly review some characteristics of complex systems and the interplay of mathematical and computational methods to study them. We then discuss these approaches, how they are implemented, and how they support one another in three settings. First, we present a study that connects weather data to seasonal population-abundance of mosquitoes, using a microscopic model. Secondly, we consider the collective motions that arise in ensembles of disks interacting through non-elastic collisions and investigate how such behaviors affect macroscopic transport properties. Finally, we consider a 'self-sorting' one-dimensional collection of point-particles. In all of these cases, agent-based models and simulations are used to guide analysis, and in the final example, we explain how the simulations led to new theorems. Articles and molecular dynamics computer codes are provided as appendices.
18
Karci, Mehmet Haydar. "Higher Order Levelable Mrf Energy Minimization Via Graph Cuts." Phd thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609408/index.pdf.
Full textAbstract:
A feature of minimizing images of a class of binary Markov random field energies is introduced and proved. Using this, the collection of minimizing images of levels of higher order, levelable MRF energies is shown to be a monotone collection.
This implies that these images can be combined to give minimizing images of the MRF energy itself. Due to the recent developments, second and third order binary MRF energies of the mentioned class are known to be exactly minimized by
maximum flow/minimum cut computations on appropriately constructed graphs. With the aid of these developments an exact and efficient algorithm to minimize levelable second and third order MRF energies, which is composed of a series of
maximum flow/minimum cut computations, is proposed and applications of the proposed algorithm to image restoration are given.
19
Bury, Thomas. "Collective behaviours in the stock market: a maximum entropy approach." Doctoral thesis, Universite Libre de Bruxelles, 2014. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209341.
Full textAbstract:
Scale invariance, collective behaviours and structural reorganization are crucial for portfolio management (portfolio composition, hedging, alternative definition of risk, etc.). This lack of any characteristic scale and such elaborated behaviours find their origin in the theory of complex systems. There are several mechanisms which generate scale invariance but maximum entropy models are able to explain both scale invariance and collective behaviours.The study of the structure and collective modes of financial markets attracts more and more attention. It has been shown that some agent based models are able to reproduce some stylized facts. Despite their partial success, there is still the problem of rules design. In this work, we used a statistical inverse approach to model the structure and co-movements in financial markets. Inverse models restrict the number of assumptions. We found that a pairwise maximum entropy model is consistent with the data and is able to describe the complex structure of financial systems. We considered the existence of a critical state which is linked to how the market processes information, how it responds to exogenous inputs and how its structure changes. The considered data sets did not reveal a persistent critical state but rather oscillations between order and disorder.
In this framework, we also showed that the collective modes are mostly dominated by pairwise co-movements and that univariate models are not good candidates to model crashes. The analysis also suggests a genuine adaptive process since both the maximum variance of the log-likelihood and the accuracy of the predictive scheme vary through time. This approach may provide some clue to crash precursors and may provide highlights on how a shock spreads in a financial network and if it will lead to a crash. The natural continuation of the present work could be the study of such a mechanism.
Doctorat en Sciences économiques et de gestion
info:eu-repo/semantics/nonPublished
20
Munyakazi, Justin Bazimaziki. "Higher Order Numerical Methods for Singular Perturbation Problems." Thesis, Online Access, 2009. http://etd.uwc.ac.za/usrfiles/modules/etd/docs/etd_gen8Srv25Nme4_6335_1277251056.pdf.
Full text
21
Picot, Gautier. "Contrôle optimal géométrique et numérique appliqué au problème de transfert Terre-Lune." Thesis, Dijon, 2010. http://www.theses.fr/2010DIJOS067/document.
Full textAbstract:
L'objet de cette thèse est de proposer une étude numérique, fondée sur l'application de résultats de la théorie du contrôle optimal géométrique, des trajectoires spatiales du système Terre-Lune dans un contexte de poussée faible. Le mouvement du satellite est décrit par les équations du problème restreint des trois corps controlé. Nous nous concentrons sur la minimisation de la consommation énergétique et du temps de transfert. Les trajectoires optimales sont recherchées parmi les projections des courbes extrémales solutions du principe du maximum de Pontryagin et peuvent être calculées grâce à une méthode de tir. Ce procédé fait intervenir l'algorithme de Newton dont la convergence nécessite une initialisation précise. Nous surmontons cette difficulté au moyen de techniques homotopiques ou d'études géométriques du système de contrôle linéarisé. L'optimalité locale des trajectoires extrémales est ensuite vérifée en utilisant les conditions du second ordre liées au concept de point conjugué. Dans le cas du problème de minimisation de l'énergie, une technique de "recollement" de trajectoires optimales kepleriennes autour de la Terre et La Lune et d'une solution optimale de l'équation du mouvement linéarisée au voisinage du point d'équilibre L1 est également proposée pour approximer les transferts Terre-Lune à énergie minimaleThis PhD thesis provides a numerical study of space trajectories in the Earth-Moon system when low-thrust is applied. Our computations are based on fundamental results from geometric control theory. The spacecraft's motion is modelled by the equations of the controlled restricted three-body problem. We focus on minimizing energy cost and transfer time. Optimal trajectories are found among a set of extremal curves, solutions of the Pontryagin's maximum principle, which can be computed solving a shooting equation thanks to a Newton algorithm. In this framework, initial conditions are found using homotopic methods or studying the linearized control system. We check local optimality of the trajectories using the second order optimality conditions related to the concept of conjugate points. In the case of the energy minimization problem, we also describe the principle of approximating Earth-Moon optimal transfers by concatening optimal keplerian trajectories around The Earth and the Moon and an energy-minimal solution of the linearized system in the neighbourhood of the equilibrium point L1
22
Ghosh, Aurobrata. "High Order Models in Diffusion MRI and Applications." Phd thesis, Université de Nice Sophia-Antipolis, 2011. http://tel.archives-ouvertes.fr/tel-00645820.
Full text
23
Nguyen, Thi Tuyen. "Comportement en temps long des solutions de quelques équations de Hamilton-Jacobi du premier et second ordre, locales et non-locales, dans des cas non-périodiques." Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1S089/document.
Full textAbstract:
La motivation principale de cette thèse est l'étude du comportement en temps grand des solutions non-bornées d'équations de Hamilton-Jacobi visqueuses dans RN en présence d'un terme d'Ornstein-Uhlenbeck. Nous considérons la même question dans le cas d'une équation de Hamilton-Jacobi du premier ordre. Dans le premier cas, qui constitue le cœur de la thèse, nous généralisons les résultats de Fujita, Ishii et Loreti (2006) dans plusieurs directions. La première est de considérer des opérateurs de diffusion plus généraux en remplaçant le Laplacien par une matrice de diffusion quelconque. Nous considérons ensuite des opérateurs non-locaux intégro-différentiels de type Laplacien fractionnaire. Le second type d'extension concerne le Hamiltonien qui peut dépendre de x et est seulement supposé sous-linéaire par rapport au gradientThe main aim of this thesis is to study large time behavior of unbounded solutions of viscous Hamilton-Jacobi equations in RN in presence of an Ornstein-Uhlenbeck drift. We also consider the same issue for a first order Hamilton-Jacobi equation. In the first case, which is the core of the thesis, we generalize the results obtained by Fujita, Ishii and Loreti (2006) in several directions. The first one is to consider more general operators. We first replace the Laplacian by a general diffusion matrix and then consider a non-local integro-differential operator of fractional Laplacian type. The second kind of extension is to deal with more general Hamiltonians which are merely sublinear
24
Thévenin, Annelyse. "Aspects algorithmiques des réarrangements génomiques : duplications et ordres partiels." Phd thesis, Université Paris Sud - Paris XI, 2009. http://tel.archives-ouvertes.fr/tel-00768996.
Full textAbstract:
La génomique comparative est une discipline importante pour la compréhension de l'évolution du vivant. Différentes méthodes de comparaison existent, nous nous intéressons ici en particulier aux mesures de (dis)similarités entre les génomes. Dans cette étude, nous étudions 3 mesures : les nombres d'adjacences, de points de cassures et d'intervalles communs. En présence de gènes dupliqués ou lorsque l'ordre des gènes n'est que partiellement connu, calculer ces mesures est un problème connu pour être NP-difficile. D'une part, nous désirons calculer les nombres d'adjacences et de points de cassures pour trois modèles (exemplaire, intermédiaire, maximum) entre deux génomes possédant des duplications. Afin d'obtenir un algorithme exact, nous modélisons ces problèmes en programmes pseudo-booléens. Après expérimentation sur 12 génomes de γ-protéobactéries, nous obtenons suffisamment de résultats pour : comparer les deux mesures et les 3 modèles et évaluer des heuristiques. À ce titre, nous proposons une famille d'heuristiques basée sur une recherche de plus longue sous-séquence commune qui donne de très bons résultats sur ces données. Parallèlement à cela, nous avons étudié, pour différents problèmes de calcul de mesures entre deux génomes avec duplication, l'approximation polynomial. D'autre part, nous calculons les nombres d'adjacences et d'intervalles communs entre deux ordres partiels (avec la possibilité qu'un des ordres soit total). Nous utilisons de nouveau une approche de programmation pseudo-booléenne. À l'aide de près de 800 génomes simulés, nous étudions l'influence de paramètres inhérents aux ordres partiels et nous comparons les deux mesures étudiées.
25
Chabot, John Alva. "VALIDATING STEADY TURBULENT FLOW SIMULATIONS USING STOCHASTIC MODELS." Miami University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=miami1443188391.
Full text
26
Fischer, Richard. "Modélisation de la dépendance pour des statistiques d'ordre et estimation non-paramétrique." Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1039/document.
Full textAbstract:
Dans cette thèse, on considère la modélisation de la loi jointe des statistiques d'ordre, c.à.d. des vecteurs aléatoires avec des composantes ordonnées presque sûrement. La première partie est dédiée à la modélisation probabiliste des statistiques d'ordre d'entropie maximale à marginales fixées. Les marginales étant fixées, la caractérisation de la loi jointe revient à considérer la copule associée. Dans le Chapitre 2, on présente un résultat auxiliaire sur les copules d'entropie maximale à diagonale fixée. Une condition nécessaire et suffisante est donnée pour l'existence d'une telle copule, ainsi qu'une formule explicite de sa densité et de son entropie. La solution du problème de maximisation d'entropie pour les statistiques d'ordre à marginales fixées est présentée dans le Chapitre 3. On donne des formules explicites pour sa copule et sa densité jointe. On applique le modèle obtenu pour modéliser des paramètres physiques dans le Chapitre 4.Dans la deuxième partie de la thèse, on étudie le problème d'estimation non-paramétrique des densités d'entropie maximale des statistiques d'ordre en distance de Kullback-Leibler. Le chapitre 5 décrit une méthode d'agrégation pour des densités de probabilité et des densités spectrales, basée sur une combinaison convexe de ses logarithmes, et montre des bornes optimales non-asymptotiques en déviation. Dans le Chapitre 6, on propose une méthode adaptative issue d'un modèle exponentiel log-additif pour estimer les densités considérées, et on démontre qu'elle atteint les vitesses connues minimax. L'application de cette méthode pour estimer des dimensions des défauts est présentée dans le Chapitre 7In this thesis we consider the modelling of the joint distribution of order statistics, i.e. random vectors with almost surely ordered components. The first part is dedicated to the probabilistic modelling of order statistics of maximal entropy with marginal constraints. Given the marginal constraints, the characterization of the joint distribution can be given by the associated copula. Chapter 2 presents an auxiliary result giving the maximum entropy copula with a fixed diagonal section. We give a necessary and sufficient condition for its existence, and derive an explicit formula for its density and entropy. Chapter 3 provides the solution for the maximum entropy problem for order statistics with marginal constraints by identifying the copula of the maximum entropy distribution. We give explicit formulas for the copula and the joint density. An application for modelling physical parameters is given in Chapter 4.In the second part of the thesis, we consider the problem of nonparametric estimation of maximum entropy densities of order statistics in Kullback-Leibler distance. Chapter 5 presents an aggregation method for probability density and spectral density estimation, based on the convex combination of the logarithms of these functions, and gives non-asymptotic bounds on the aggregation rate. In Chapter 6, we propose an adaptive estimation method based on a log-additive exponential model to estimate maximum entropy densities of order statistics which achieves the known minimax convergence rates. The method is applied to estimating flaw dimensions in Chapter 7
27
Meisner, Maëlis. "Étude unifiée d'équations aux dérivées partielles de type elliptique régies par des équations différentielles à coefficients opérateurs dans un cadre non commutatif : applications concrètes dans les espaces de Hölder et les espaces Lp." Phd thesis, Université du Havre, 2012. http://tel.archives-ouvertes.fr/tel-00712008.
Full textAbstract:
L'objectif de ce travail est l'étude des équations différentielles complètes du second ordre de type elliptique à coefficients opérateurs dans un espace de Banach X quelconque. Une application concrète de ces équations est détaillée, il s'agit d'un problème de transmission du potentiel électrique dans une cellule biologique où la membrane constitue une couche mince. L'originalité de ce travail réside particulièrement dans le fait que les opérateurs non bornés considérés ne commutent pas nécessairement. Une nouvelle hypothèse dite de non commutativité est alors introduite. L'analyse est faite dans deux cadres fonctionnels distincts: les espaces de Hölder et les espaces Lp (avec X un espace UMD). L'équation est d'abord étudiée sur la droite réelle puis sur un intervalle borné avec conditions aux limites de Dirichlet. On donne des résultats d'existence, d'unicité et de régularité maximale de la solution classique sous des conditions sur les données dans des espaces d'interpolation. Les techniques utilisées sont basées sur la théorie des semi-groupes, le calcul fonctionnel de Dunford et la théorie de l'interpolation. Ces résultats sont tous appliqués à des équations aux dérivées partielles concrètes de type elliptique ou quasi-elliptique.
28
BARROS, Fabiana Uchôa. "Matriz de covariâncias do estimador de máxima verossimilhança corrigido pelo viés em modelos lineares generalizados com parâmetro de dispersão desconhecido." Universidade Federal de Campina Grande, 2011. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/1278.
Full textAbstract:
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-07-27T16:10:22Z
No. of bitstreams: 1
FABIANA UCHÔA BARROS - DISSERTAÇÃO PPGMAT 2011..pdf: 444205 bytes, checksum: dd1ada684703bcb400e631c5f044668b (MD5)Made available in DSpace on 2018-07-27T16:10:22Z (GMT). No. of bitstreams: 1 FABIANA UCHÔA BARROS - DISSERTAÇÃO PPGMAT 2011..pdf: 444205 bytes, checksum: dd1ada684703bcb400e631c5f044668b (MD5) Previous issue date: 2011-12
Capes
Com base na expressão de Pace e Salvan (1997 pág. 30), obtivemos a matriz de covariâncias de segunda ordem dos estimadores de máxima verossimilhança corrigidos pelo viés de ordem n−1 em modelos lineares generalizados, considerando o parâmetro de dispersão desconhecido, porém o mesmo para todas as observações. A partir dessa matriz, realizamos modi cações no teste de Wald. Os resultados obtidos foram avaliados através de estudos de simulação de Monte Carlo.
Based on the expression of Pace and Salvan (1997 pág. 30), we obtained the second order covariance matrix of the of the maximum likelihood estimators corrected for bias of order n−1in generalized linear models, considering that the dispersion parameter is the same although unknown for all observations. From this matrix, we made modi cations to the Wald test. The results were evaluated through simulation studies of Monte Carlo.
29
Avilès, Cruz Carlos. "Analyse de texture par statistiques d'ordre superieur : caracterisation et performances." Grenoble INPG, 1997. http://www.theses.fr/1997INPG0001.
Full textAbstract:
Dans le cadre statistique, chercher a classer et a segmenter des textures a grain fin, c'est souvent utiliser des statistiques d'ordre un et d'ordre deux mais parfois ceux-ci sont insuffisantes. Une autre alternative est d'utiliser les statistiques d'ordre superieur, plus particulierement les moments d'ordre trois et d'ordre quatre. Dans ce travail, on met en place une methodologie d'experimentation ayant pour but de faire de la classification et de la segmentation de micro-textures, a l'aide de ces statistiques d'ordre trois et quatre. Deux methodes pour la classification et la segmentation de micro-textures sont mise en place, d'une part une methode supervisee et d'autre part une methode non supervisee. Cette derniere est basee sur l'algorithme em. Du fait de la redondance importante d'information sous-jacente aux moments statistiques, des methodes de reduction et de selection de dimension sont testees. D'une part, pour la reduction de dimension on a utilise l'analyse en composantes principales (acp) et l'analyse en composantes curvilignes (acc). D'autre part, pour la selection d'attributs la methode branch and bound a ete utilisee. Ces methodes ont ete explorees sur les attributs statistiques afin d'utiliser les plus discriminants soit dans l'espace original, soit dans un espace de projection. Puisqu'aucune famille de parametres prise isolement (statistique d'ordre un, deux, trois et quatre) ne suffit pour faire la discrimination d'une large gamme de textures, on est oblige de faire leur mise en cooperation via la fusion de donnees, fournissant une solution performante en reconnaissance.
30
Ennaoui, Karima. "Computational aspects of infinite automata simulation and closure system related issues." Thesis, Université Clermont Auvergne (2017-2020), 2017. http://www.theses.fr/2017CLFAC031/document.
Full textAbstract:
La thèse est consacrée à des problématiques d’algorithmique et de complexité sur deux sujets. Le premier sujet s’intéresse à la composition comportementale des services web. Ce problème a été réduit à la simulation d’un automate par le produit fermé d’un ensemble d’automates. La thèse étudie dans sa première partie la complexité de ce problème en considérant deux paramètres : le nombre des instances considéré de chaque service et la présence des états hybrides : état à la fois intermédiaire et final dans un automate. Le second sujet porte sur les systèmes de fermeture et s’intéresse au calcul de l’extension maximale d’un système de fermeture ainsi qu’à l’énumération des clefs candidates d’une base implicative. On donne un algorithme incrémental polynomial qui génère l’extension maximale d’un treillis codé par une relation binaire. Puis, la notion de key-ideal est définie, en prouvant que leur énumération est équivalente à l’énumération des clefs candidates. Ensuite, on donne un algorithme qui permet de générer les key-ideal minimaux en temps incrémental polynomial et les key-ideal non minimaux en délai polynomialThis thesis investigates complexity and computational issues in two parts. The first concerns an issue related to web services composition problem: Deciding whether the behaviour of a web service can be composed out of an existing repository of web services. This question has been reduced to simulating a finite automata to the product closure of an automata set. We study the complexity of this problem considering two parameters; the number of considered instances in the composition and the presence of the so-called hybrid states (states that are both intermediate and final). The second part concerns closure systems and two related issues; Maximal extension of a closure system : we give an incremental polynomial algorithm that computes a lattice's maximal extension when the input is a binary relation. Candidate keys enumeration : we introduce the notion of key-ideal sets and prove that their enumeration is equivalent to candidate keys enumeration. We then give an efficient algorithm that generates all non-minimal key-ideal sets in a polynomial delay and all minimal ones in incremental polynomial time
31
Barros, Fabiana Uchôa. "Refinamentos assintóticos em modelos lineares generalizados heteroscedáticos." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/45/45133/tde-12052017-103436/.
Full textAbstract:
Nesta tese, desenvolvemos refinamentos assintóticos em modelos lineares generalizados heteroscedásticos (Smyth, 1989). Inicialmente, obtemos a matriz de covariâncias de segunda ordem dos estimadores de máxima verossimilhança corrigidos pelos viés de primeira ordem. Com base na matriz obtida, sugerimos modificações na estatística de Wald. Posteriormente, derivamos os coeficientes do fator de correção tipo-Bartlett para a estatística do teste gradiente. Em seguida, obtemos o coeficiente de assimetria assintótico da distribuição dos estimadores de máxima verossimilhança dos parâmetros do modelo. Finalmente, exibimos o coeficiente de curtose assintótico da distribuição dos estimadores de máxima verossimilhança dos parâmetros do modelo. Analisamos os resultados obtidos através de estudos de simulação de Monte Carlo.In this thesis, we have developed asymptotic refinements in heteroskedastic generalized linear models (Smyth, 1989). Initially, we obtain the second-order covariance matrix for the maximum likelihood estimators corrected by the bias of first-order. Based on the obtained matrix, we suggest changes in Wald statistics. In addition, we derive the coeficients of the Bartlett-type correction factor for the statistical gradient test. After, we get asymptotic skewness of the distribution of the maximum likelihood estimators of the model parameters. Finally, we show the asymptotic kurtosis coeficient of the distribution of the maximum likelihood estimators of the model parameters. Monte Carlo simulation studies are developed to evaluate the results obtained.
32
Cots, Olivier. "Contrôle optimal géométrique : méthodes homotopiques et applications." Phd thesis, Université de Bourgogne, 2012. http://tel.archives-ouvertes.fr/tel-00742927.
Full textAbstract:
Le contexte de ce travail est le contrôle optimal géométrique appliqué à la mécanique céleste et au contrôle quantique. On s'est tout d'abord intéressé au problème de transfert orbital de satellite autour de la Terre à consommation minimale, qui amena à la réalisation du code HamPath, permettant tout d'abord la résolution de problèmes de contrôle optimal dont la loi de commande est lisse. Il se base sur le Principe du Maximum de Pontryagin (PMP) et sur la notion de point conjugué. Ce programme combine méthodes de tir, méthodes homotopiques différentielles et calcul des conditions d'optimalité du deuxième ordre. Nous nous intéressons par la suite au contrôle quantique. On étudie tout d'abord le contrôle d'un système composé de deux types de particules de spin 1/2 ayant des temps de relaxation différents et dont la dynamique est gouvernée par les équations de Bloch. Ces deux sous-systèmes, correspondant aux deux types de particules, sont couplés par un même contrôle (un champ electromagnétique), le but étant alors d'amener la magnétisation des particules du premier type à zéro tout en maximisant celle du second (dans un système de coordonnées bien choisi). Ce modèle intervient en imagerie médicale par Résonance Magnétique Nucléaire et consiste à maximiser le contraste entre deux régions d'une même image. L'utilisation des outils géométriques et numériques aura permis de donner une très bonne synthèse sous-optimale pour deux cas particuliers (mélange sang oxygéné/désoxygéné et liquide cérébrospinal/eau). La dernière contribution de cette thèse porte sur l'étude d'un système quantique à deux niveaux d'énergie dont la dynamique est régie par les équations de Lindblad. Le modèle est basé sur la minimisation d'énergie du transfert. On se restreint à un cas particulier pour lequel le Hamiltonien donné par le PMP est Liouville intégrable. On décrit alors les lieux conjugué et de coupure pour ce problème riemannien avec dérive.
33
Kratz, Marie. "Some contributions in probability and statistics of extremes." Habilitation à diriger des recherches, Université Panthéon-Sorbonne - Paris I, 2005. http://tel.archives-ouvertes.fr/tel-00239329.
Full text
34
Zaylaa, Amira. "Analyse et extraction de paramètres de complexité de signaux biomédicaux." Thesis, Tours, 2014. http://www.theses.fr/2014TOUR3315/document.
Full textAbstract:
L'analyse de séries temporelles biomédicales chaotiques tirées de systèmes dynamiques non-linéaires est toujours un challenge difficile à relever puisque dans certains cas bien spécifiques les techniques existantes basées sur les multi-fractales, les entropies et les graphes de récurrence échouent. Pour contourner les limitations des invariants précédents, de nouveaux descripteurs peuvent être proposés. Dans ce travail de recherche nos contributions ont porté à la fois sur l’amélioration d’indicateurs multifractaux (basés sur une fonction de structure) et entropiques (approchées) mais aussi sur des indicateurs de récurrences (non biaisés). Ces différents indicateurs ont été développés avec pour objectif majeur d’améliorer la discrimination entre des signaux de complexité différente ou d’améliorer la détection de transitions ou de changements de régime du système étudié. Ces changements agissant directement sur l’irrégularité du signal, des mouvements browniens fractionnaires et des signaux tirés du système du Lorenz ont été testés. Ces nouveaux descripteurs ont aussi été validés pour discriminer des fœtus en souffrance de fœtus sains durant le troisième trimestre de grossesse. Des mesures statistiques telles que l’erreur relative, l’écart type, la spécificité, la sensibilité ou la précision ont été utilisées pour évaluer les performances de la détection ou de la classification. Le fort potentiel de ces nouveaux invariants nous laisse penser qu’ils pourraient constituer une forte valeur ajoutée dans l’aide au diagnostic s’ils étaient implémentés dans des logiciels de post-traitement ou dans des dispositifs biomédicaux. Enfin, bien que ces différentes méthodes aient été validées exclusivement sur des signaux fœtaux, une future étude incluant des signaux tirés d’autres systèmes dynamiques nonlinéaires sera réalisée pour confirmer leurs bonnes performancesThe analysis of biomedical time series derived from nonlinear dynamic systems is challenging due to the chaotic nature of these time series. Only few classical parameters can be detected by clinicians to opt the state of patients and fetuses. Though there exist valuable complexity invariants such as multi-fractal parameters, entropies and recurrence plot, they were unsatisfactory in certain cases. To overcome this limitation, we propose in this dissertation new entropy invariants, we contributed to multi-fractal analysis and we developed signal-based (unbiased) recurrence plots based on the dynamic transitions of time series. Principally, we aim to improve the discrimination between healthy and distressed biomedical systems, particularly fetuses by processing the time series using our techniques. These techniques were either validated on Lorenz system, logistic maps or fractional Brownian motions modeling chaotic and random time series. Then the techniques were applied to real fetus heart rate signals recorded in the third trimester of pregnancy. Statistical measures comprising the relative errors, standard deviation, sensitivity, specificity, precision or accuracy were employed to evaluate the performance of detection. Elevated discernment outcomes were realized by the high-order entropy invariants. Multi-fractal analysis using a structure function enhances the detection of medical fetal states. Unbiased cross-determinism invariant amended the discrimination process. The significance of our techniques lies behind their post-processing codes which could build up cutting-edge portable machines offering advanced discrimination and detection of Intrauterine Growth Restriction prior to fetal death. This work was devoted to Fetal Heart Rates but time series generated by alternative nonlinear dynamic systems should be further considered
35
Dakkoune, Amine. "Méthodes pour l'analyse et la prévention des risques d'emballement thermique Zero-order versus intrinsic kinetics for the determination of the time to maximum rate under adiabatic conditions (TMR_ad): application to the decomposition of hydrogen peroxide Risk analysis of French chemical industry Fault detection in the green chemical process : application to an exothermic reaction Analysis of thermal runaway events in French chemical industry Early detection and diagnosis of thermal runaway reactions using model-based approaches in batch reactors." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMIR30.
Full textAbstract:
L’histoire des événements accidentels dans les industries chimiques montre que leurs conséquences sont souvent graves sur les plans humain, environnemental et économique. Cette thèse vise à proposer une approche de détection et de diagnostic des défauts dans les procédés chimiques afin de prévenir ces événements accidentels. La démarche commence par une étude préalable qui sert à identifier les causes majeures responsables des événements industriels chimiques en se basant sur le retour d’expérience (REX). En France, selon la base de données ARIA, 25% des évènements sont dus à l’emballement thermique à cause d’erreurs d’origine humaine. Il est donc opportun de développer une méthode de détection et de diagnostic précoce des défauts dus à l’emballement thermique. Pour cela nous développons une approche qui utilise des seuils dynamiques pour la détection et la collecte de mesures pour le diagnostic. La localisation des défauts est basée sur une classification des caractéristiques statistiques de la température en fonction de plusieurs modes défectueux. Un ensemble de classificateurs linéaires et de diagrammes de décision binaires indexés par rapport au temps sont utilisés. Enfin, la synthèse de l'acide peroxyformique dans un réacteur discontinu et semi-continu est considérée pour valider la méthode proposée par des simulations numériques et ensuite expérimentales. Les performances de détection de défauts se sont révélées satisfaisantes et les classificateurs ont démontré un taux de séparabilité des défauts élevésThe history of accidental events in chemical industries shows that their human, environmental and economic consequences are often serious. This thesis aims at proposing an approach of detection and diagnosis faults in chemical processes in order to prevent these accidental events. A preliminary study serves to identify the major causes of chemical industrial events based on experience feedback. In France, according to the ARIA database, 25% of the events are due to thermal runaway because of human errors. It is therefore appropriate to develop a method for early fault detection and diagnosis due to thermal runaway. For that purpose, we develop an approach that uses dynamical thresholds for the detection and collection of measurements for diagnosis. The localization of faults is based on a classification of the statistical characteristics of the temperature according to several defectives modes. A multiset of linear classifiers and binary decision diagrams indexed with respect to the time are used for that purpose. Finally, the synthesis of peroxyformic acid in a batch and semi batch reactor is considered to validate the proposed method by numerical simulations and then experiments. Faults detection performance has been proved satisfactory and the classifiers have proved a high isolability rate of faults
36
Alenezi, Saleh. "Micropalaeontology, palaeoenvironments and sequence stratigraphy of the Sulaiy Formation of eastern Saudi Arabia." Thesis, University of Plymouth, 2016. http://hdl.handle.net/10026.1/9330.
Full textAbstract:
The Sulaiy Formation, which is the oldest unit in the Lower Cretaceous succession, is conformably overlain by the Yamama Formation and it is a challenge to identify the precise age of the two formations using foraminifera and other microfossil assemblages. In the eastern side of Saudi Arabia, the Sulaiy Formation and the base of Yamama Formation are poorly studied. The main objectives of this study is to enhance the understanding of the Sulaiy Formation sequence stratigraphical correlation, regional lateral variations and palaeoenvironmental investigation. Lithological and semi-quantitative micropalaeontological analysis of 1277 thin sections taken from core samples from nine cored wells providing a geographically representative distribution from the Saudi Arabian Gulf. These cores intersected the base of the Yamama Formation and the Sulaiy Formation in the total thickness of cored wells of 843.23 meters (2766.5 feet). On the evidence provided by the foraminifera, the Sulaiy Formation is considered to represent the Berriasian to the lowermost Valanginian. The investigation of the micropalaeontology has provided considerable insights into the biocomponents of Sulaiy and the base of Yamama formations in order to identify their biofacies. These microfossils include rotalid foraminifera, miliolid foraminifera, agglutinated foraminifera, calcareous algae, calcispheres, stromatoporoids, sponge spicules, problematica (e.g. Lithocodium aggregatum), molluscs, corals, echinoderms and ostracods. Systematics of planktic and benthic foraminifera is accomplished using the foraminiferal classification by Loeblich and Tappan (1988) as the main source. The assemblage contains foraminifera that recorded for the first time in the Sulaiy Formation. Other microfossils were identified and recorded to help in the identification of the sedimentary environments. The investigation of the micropalaeontology and the lithofacies analysis have provided evidence the identification of the various lithofacies. About twenty four microfacies were identified on the basis of their bio−component and non-skeletal grains. The lithofacies and the bio−component results have provided the evidence of the sedimentary palaeoenvironmental model namely the Arabian Rimmed Carbonate Platform. This palaeoenvironmental depositional model is characterised by two different platform regimes. They are the Platform Interior and the Platform Exterior each of which have unique sedimentary lithofacies zones that produce different types of lithofacies. Each lithofacies is characterised by special depositional conditions and palaeobathymetry that interact with sea level changes and the accommodation space. The important palaeoenvironments are intertidal, restricted lagoon (subtidal), open marine, deeper open marine, inner shoal, shoal and platform margin. Generating, and testing, a depositional model as a part of formulating a sequence stratigraphical interpretation of a region is a key to understanding its geological development and – ultimately – reservoir potential. The micropalaeontology and sedimentology of the Sulaiy Formation in the subsurface have indicated a succession of clearly defined shallowing−upwards depositional cycles. These typically commence with a deep marine biofacies with wackestones and packstones, capped with a mudstone-wackestone maximum flooding zone and an upper unit of packstone to grainstones containing shallow marine biofacies. The upper part of the Sulaiy Formation is highstand-dominated with common grainstones that host the Lower Ratawi reservoir which is capped by karst that defines the sequence boundary. This karst is identified by its abundant moldic porosity that enhanced the the reservoir quality by increasing its porosities into greater values. Integration of the sedimentology and micropalaeontology has yielded a succession of shoaling−upwards depositional cycles, considered to be 4th order sequences, that are superimposed on a large scale 3rd order system tract shallowing−upwards, highstand-associated sequence of the Sulaiy Formation. The Lower Ratawi Reservoir is located within the latest high-stand portion of a third-order Sulaiy Formation sequence. The reservoir consists of a succession of several sequences, each of which is sub-divided into a lower transgressive systems tract separated from the upper highstand systems tract by a maximum flooding surface (MFS/Z). The last of these depositional cycles terminates in beds of porous and permeable ooid, or ooidal-peloidal, grainstone. The reservoir is sealed by the finer-grained sediments of the Yamama Formation.
37
Silva, Domingos José Lopes da. "Estatística de extremos: limites da performance humana - estudo com lançadores e saltadores do atletismo." Doctoral thesis, Universidade de Évora, 2020. http://hdl.handle.net/10174/28600.
Full textAbstract:
Eventos extremos são raros, mas quando ocorrem têm um enorme impacto social e uma atenção
mediática considerável. São exemplo os recordes no mundo do desporto – raros de acontecerem, mas
quando ocorrem não apenas são divulgados nos mais variados meios de comunicação social, como são
motivo de modificação da metodologia de treino e do comportamento do atleta. Como prever esta
ocorrência? Qual a probabilidade de ocorrência? Qual a magnitude da ocorrência? Quanto tempo de
espera? A teoria de valores extremos, baseada no teorema dos tipos extremais de Fisher-Tippett-
Gnedenko, proporciona um rigoroso quadro de análise dos valores extremos, estimando a probabilidade
de ocorrência de eventos que estão para além da amostra disponível. Assim, sob a questão “qual o limite
da performance humana?”, este trabalho no domínio da Estatística de Extremos tem aplicações ao
desporto de alto rendimento, particularmente às especialidades de lançamentos e saltos do atletismo.
Foram utilizadas as metodologias: (i) r-maiores observações, (ii) excessos acima de um limiar, e (iii)
máximos de blocos não-estacionários. Decidida a distribuição limite do máximo associado ao evento
em estudo e o modelo que melhor se adequa aos dados disponíveis, a estimação pontual dos parâmetros
extremais foi realizada por máxima verosimilhança e a estimação intervalar pelo método delta e pela
função profile log-likelihood. Em cada método foram testados diversos modelos. Recorremos a técnicas
gráficas, estabilidade dos erros-padrão, intervalos de confiança, testes de hipóteses e algumas métricas
de erro, para verificação do ajustamento dos modelos aos dados disponíveis. Estamos particularmente
interessados na estimação de quantis extremais, probabilidades de excedência, limite superior do
suporte, níveis de retorno e período de retorno. Os resultados mostram que nos lançamentos do martelo,
disco e dardo feminino existe uma forte probabilidade de se conseguir um novo recorde do mundo e que
nos lançamentos masculinos tal probabilidade é reduzida. Com exceção do triplo-salto, nas restantes
especialidades de saltos, o período de retorno (i.e., número de máximos individuais) até à ocorrência de
um novo recorde do mundo é menor nas mulheres do que nos homens; ABSTRACT:
Statistics of Extremes: limits of human performance - study with throwers and jumpers
in athletics
Extreme events are rare, but when they do occur, they have an enormous social impact and they receive
a considerable media attention. Such is the case of world records in sport – they rarely happen, but when
they do, not only are they disclosed by all media, but they also cause changes in the training methodology
and in the athlete's behaviour. How to predict this occurrence? What is the probability of occurrence?
What is the magnitude of the occurrence? How long is the wait? The extreme value theory, based on the
Fisher-Tippett-Gnedenko theorem, provides a rigorous framework for analysing extreme values,
estimating the probability of the occurrence of events that are beyond the sample. Thus, research within
the area of Extreme Statistics provide information to answer the question “what is the limit of human
performance?” in the framework of high-performance sport, particularly in the case of the specialties of
throwing and jumping in athletics. The methodologies used were: (i) r-largest order statistics, (ii) peaks
over threshold, and (iii) non-stationary annual maximum. Once decided the limit distribution of the
maximum associated with the event under study and the model that best fits the available data, the point
estimation of the extremal parameters were performed by maximum likelihood estimation, with Nelder-
Mead or BFGS optimization and the interval estimation using the delta method and the profile loglikelihood
function. In each method, several models were tested. We used graphical techniques, stability
of standard errors, confidence intervals, hypothesis tests and some error metrics, to verify if the models
fit the available data. We were particularly interested in the estimation of extreme quantiles, exceedance
probability, right endpoint, return levels and return period. The results suggest that in hammer, discus
and javelin throwing there are a strong probability of a new world record will be achieved. In the case
of male, throwing events, the forecast of a new world record being achieved with reduced probability.
With exception of triple-jump, in all other jumping specialities, the return period (i.e., number of
individual maximums) until the occurrence of a new world record is shorter in women than in men.
38
MEDEIROS, Rex Antonio da Costa. "Zero-Error capacity of quantum channels." Universidade Federal de Campina Grande, 2008. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/1320.
Full textAbstract:
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-08-01T21:11:37Z
No. of bitstreams: 1
REX ANTONIO DA COSTA MEDEIROS - TESE PPGEE 2008..pdf: 1089371 bytes, checksum: ea0c95501b938e0d466779a06faaa4f6 (MD5)Made available in DSpace on 2018-08-01T21:11:37Z (GMT). No. of bitstreams: 1 REX ANTONIO DA COSTA MEDEIROS - TESE PPGEE 2008..pdf: 1089371 bytes, checksum: ea0c95501b938e0d466779a06faaa4f6 (MD5) Previous issue date: 2008-05-09
Nesta tese, a capacidade erro-zero de canais discretos sem memória é generalizada para canais quânticos. Uma nova capacidade para a transmissão de informação clássica através de canais quânticos é proposta. A capacidade erro-zero de canais quânticos (CEZQ) é definida como sendo a máxima quantidade de informação por uso do canal que pode ser enviada através de um canal quântico ruidoso, considerando uma probabilidade de erro igual a zero. O protocolo de comunicação restringe palavras-código a produtos tensoriais de estados quânticos de entrada, enquanto que medições coletivas entre várias saídas do canal são permitidas. Portanto, o protocolo empregado é similar ao protocolo de Holevo-Schumacher-Westmoreland. O problema de encontrar a CEZQ é reformulado usando elementos da teoria de grafos. Esta definição equivalente é usada para demonstrar propriedades de famílias de estados quânticos e medições que atingem a CEZQ. É mostrado que a capacidade de um canal quântico num espaço de Hilbert de dimensão d pode sempre ser alcançada usando famílias compostas de, no máximo,d estados puros. Com relação às medições, demonstra-se que medições coletivas de von Neumann são necessárias e suficientes para alcançar a capacidade. É discutido se a CEZQ é uma generalização não trivial da capacidade erro-zero clássica. O termo não trivial refere-se a existência de canais quânticos para os quais a CEZQ só pode ser alcançada através de famílias de estados quânticos não-ortogonais e usando códigos de comprimento maior ou igual a dois. É investigada a CEZQ de alguns canais quânticos. É mostrado que o problema de calcular a CEZQ de canais clássicos-quânticos é puramente clássico. Em particular, é exibido um canal quântico para o qual conjectura-se que a CEZQ só pode ser alcançada usando uma família de estados quânticos não-ortogonais. Se a conjectura é verdadeira, é possível calcular o valor exato da capacidade e construir um código de bloco quântico que alcança a capacidade. Finalmente, é demonstrado que a CEZQ é limitada superiormente pela capacidade de Holevo-Schumacher-Westmoreland.
39
Lee, Cheng-Gang, and 李承芳. "Second-Order Asymmetric BAM Design with a Maximal Basin of Attraction." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/87999702051765376849.
Full textAbstract:
碩士國立交通大學
電機與控制工程系
90
Bidirectional Associative Memory (BAM) generalizes the Associative Memory (AM) to be capable of performing two-way recalling of pattern pairs. Recently﹐BAM has played the vital role in AM research. Asymmetric Bidirectional Associative Memory (ABAM) is a variant of BAM relaxed with connection weight symmetry restriction and enjoys a much better performance than a conventional BAM structure. Higher-Order Associative Memories (HOAMs) are reputed for their higher memory capacity than the first-order counterpart﹐yet there are few HOAMs design schemes proposed up to date. To this need﹐we are concerned in this paper with designing a second-order asymmetric bidirectional associative memory (SOABAM) with a maximal basin of attraction ﹐whose extension to a HOABAM is possible and straightforward. First﹐a sufficient condition is derived for the connection weight matrix of SOABAM that can guarantee the recall of all prototype pattern pairs. To respect the complete recall theorem﹐a local training rule﹐which is also adaptive in learning step size﹐is formulated﹐and it leads to a faster design time. Then derived is a theorem that states designing a SOABAM further enlarging the quantities required to meet the complete theorem will enhance the capability of evolving a noisy pattern to converge to its association pattern vector without error. Based on this theorem﹐our algorithm is also modified to ensure each training pattern is stored with a basin of attraction as large as possible. Computer simulations over the color graphics adapter (CGA) fonts have demonstrated the superiority of the proposed local training rule over other prevailing BAM schemes.
40
Chang, Yi-Hsing, and 張儀興. "A Study on Generating All Maximal Independent Sets in Lexicographic Order." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/27406641846612197859.
Full text
41
Lin, Ching-Sou, and 林慶壽. "Maximum Principles for Some Higher Order Elliptic Equations." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/59167072269683969216.
Full text
42
LIN, TZU-YUN, and 林紫筠. "Bicriterion total flowtime and maximum tardiness minimization order scheduling problem." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/37akg7.
Full textAbstract:
碩士逢甲大學
統計學系
105
The order scheduling problem arises in numerous production scheduling environments. The research community discusses and studies several measurable criteria, such as the makespan, mean flow time, and mean tardiness, are most commonly used. Although the order scheduling model with a single objective has been widely studied, it is at odds with real-life scheduling practices. In practice, a typical manager must optimize multiple objectives. A search of the literature revealed no articles on how to optimize an order scheduling problem with multiple objectives. Therefore, an order scheduling model to minimize the linear sum of the total flowtime and the maximum tardiness is introduced in this study. Specifically, several dominance relations and a lower bound are derived to expedite the search for the optimal solution. Three modified heuristics are proposed for finding near-optimal solutions. A hybrid iterative greedy algorithm and a particle swarm colony algorithm are proposed to solve this problem. Finally, the performance levels of all proposed algorithms are evaluated according to test results.
43
Chiou, Tzung-je, and 邱宗哲. "A Weight-Order-Based Lattice Algorithm for Mining Maximal Weighted Frequent Patterns over a Data Stream Sliding Window." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/t2y2cb.
Full textAbstract:
碩士國立中山大學
資訊工程學系研究所
103
Weighted frequent pattern mining in data streams is an important field for the real world, such as the supermarket. Moreover, mining the weighted maximal frequent patterns is also an important issue. The weighted maximal frequent pattern is the pattern which is not the subset of any other pattern and the weighted support is larger than the threshold. However, many previous Apriori-like algorithms cannot be used in weighted frequent pattern mining. The reason is that even through a subset X of a pattern Y is not a weighted frequent pattern, the pattern Y may be a weighted frequent pattern. Besides, because data streams are continuous, high speed, unbounded, and real time, we can only scan once for the data streams. Therefore, the previous algorithms in the traditional databases are not suitable for the data streams. Furthermore, many applications are interested in the recent data streams, and the sliding window is the model which deals with the most recent data streams. In order to solve mining weighted maximal frequent patterns based on the sliding window model, Ryu et al. propose the WMFP-SW algorithm. The WMFP-SW algorithm uses the FP-tree to mine the weighted maximal frequent patterns. It also uses maximal weight to prune the patterns. But it takes long time in mining the weighted maximal frequent patterns. Because when the new transaction comes, the WMFP-SW algorithm always has to reconstruct the FP-tree. Moreover, the WMFP-SW algorithm may have a missing case. To solve those problems, in this thesis, we propose the Weighted-Order-Based Lattice algorithm based on the sliding window model. We use the lattice structure to store the information of the transactions. The structure of the lattice stores the relationship between the child node and the father node. In each node, we record the itemset and the count. When the new transaction comes, we consider five relations: (1) equivalent, (2) subset, (3) intersection, (4) empty set, (5) superset. With those five relations, we can add the new transactions and update the support efficiently. Moreover, we use global maximal weight pruning strategy and local maximal weight pruning strategy to avoid generating invalid candidate patterns. From the the performance study, including the real data and synthetic data, we show that theWeighted-Order-Based Lattice algorithm provides better performance than the WMFP-SW algorithm both in the case of real data and the case of simulation in both cases.
44
Lin, Chang I., and 張鎰麟. "Analysis of Build-to-Order Model for Maximum Profit of PCB Products." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/18077499516714278722.
Full textAbstract:
碩士開南管理學院
企業管理學系碩士班
94
In accordance to the market trend, different product has the different demand of manufacturing process, the different resources utilization, the different yield and the profit; even if the printed circuit board industry manufacturers also face the same problems of resources utilization to obtain a best balanced point between cost and profit. This research is to take the limit to production capacity of Theory of Constrains (TOC) as the restriction factor, apply mathematics linear programming, with the coordinate of yield and idle costs to decide the best bill-to-order (BTO) production combination. It attempts to help the printed circuit board company achieve the profit maximization under the in-time delivery situation with the best bill-to-order (BTO) production combination. The research uses the data of the production of the case company to perform the empirical study. To attain the maximum profit, there are three different models explored: with current manufacturing production capacity to decide the best bill-to-order (BTO) production combination, with the yield improvement to decide the best bill-to-order (BTO) production combination, with the expansion of the bottleneck of production to decide the best bill-to-order (BTO) production combination. From the analysis results, the conclusions are as follows: 1. under the consideration of idle costs may truly affect bill-to-order (BTO) production combination, although throughput contribution is not the maximum, the actual profit is really highest; 2. the yield improvement may create a higher profit; 3. properly expanding the bottlenecks of production capacity may achieve the actual profit maximization.
45
Liao, Dart, and 廖志剛. "The Maximum Power Point Tracking of Renewable Energy using Fractional Order Differential." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/44375171650176139487.
Full textAbstract:
碩士國立勤益科技大學
電機工程系
103
With the growing popularity of renewable energy, a number of methods for Maximum Power Point Tracking of these energy sources are in use. All these methods have one common drawback, they are carried out during steady state operation and this causes power and voltage disturbance. This not only reduces output efficiency but also has an effect on the life of the converter and other electronic components. We propose a fractional differential incremental conductance method (FOINC) based on a chaotic synchronization dynamic error fractional order differential voltage detector of another MPPT auxiliary controller. The voltage detector is the most important feature of renewable energy maximum power point tracking in different environments. This method can reduce power losses and increase the life of electronic components using MPPT chaotic synchronization dynamic error detection during continuous operation. MPPT renewable energy simulation was carried out using Matlab/Simulink and various traditional methods were compared. The results showed that this method has good MPPT steady-state. Careful experimental work with real circuits produced results that were compatible to the simulations and proved the theoretical maximum power tracking method described in this paper to be applicable in practice.
46
SU, JING-LIN, and 蘇鏡霖. "Maximum Power Point Tracking for PV Systems Based on Fractional Order Particle Swarm Optimization." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/ftbnb5.
Full textAbstract:
碩士國立中正大學
電機工程研究所
106
This thesis applies the fractional order particle swarm optimization (FPSO) with a 2kW series buck-boost converter, which is self-developed and has functions of buck and boost, as the maximum power point tracker (MPPT) of the solar photovoltaic system. The aim is to achieve maximum power output of solar photovoltaic panels under ideal atmospheric conditions or partial shading conditions. Based on PSO, FPSO extends the velocity and position formula to fractional order, where the fractional order a, b and truncation order L are the key parameters of FPSO performance. Due to the memory characteristics of the FPSO, it can use the position and velocity data in previous generations to judge the position and speed in the next generation such that the tracking accuracy and tracking time is improved. FPSO can promote the convergence speed and tracking ability of the algorithm. If the FPSO is applied to the maximum power tracking system, the tracking time can be reduced and the tracking accuracy can be improved under both single-peak and multi-peak conditions. Finally, the performances of the proposed FPSO in tracking speed and tracking accuracy are verified by experiments of single-peak curves, multi-peak curves, insolation variations, and temperature variations. Compared with the traditional PSO, the proposed FPSO has better tracking speed and tracking accuracy regardless of single-peak curves, multi-peak curves, insolation variations, and temperature variations.
47
Kuo, Shin-Yi, and 郭欣儀. "Seasonal Variations of Leaf Order and Leaf Age whenReaching Maximum Photosynthetic Rate in SevenTree Species." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/93378735146402818893.
Full textAbstract:
碩士國立屏東科技大學
森林系所
103
In the past, researchers normally chose newly matured leaves, or leaves at the 3~5 sprouting orders from top of a branch, to measure the photosynthetic rate of a plant. However, this measuring method which based on past experiences did not provide quantitative data for references. The objectives of this research were to investigate the differences of maximum photosynthetic rate (Amax) in different leaf orders of a species during various seasons, and at which leaf order does the Amax occur. Seven species of various shade tolerance classes, including shade-intolerant species Broussonetia papyrifera and Premna serratifolia, moderate shade-tolerant species including Margaritaria indica, Michelia formosana and Heritiera littoralis, shade-tolerant species Gelonium aequoreum and Drypetes littoralis were selected for this study. Ten branches from 3~4 saplings within the range of 1.5~3.0 m in height of each species were tagged for their newly sprout leaves. Photosynthetic rates of each leaf during the four seasons were measured since August, 2013. With these obtained informations, we then knew the leaf order at the branch and leaf age when it reached Amax in various seasons, and thereby calculated leaf sprouting rates in different seasons. Our results showed that, during spring and summer seasons, leaves which had reached Amax were mostly at the 4th~6th leaf orders of morphologically matured leaves in B. papyrifera, Mar. indica, H. littoralis, and D. littoralis, while they were mostly at the 3rd leaf order in P. serratifolia, Mic. formosana, and G. aequoreum. During autumn and winter seasons, leaves which had reached Amax were mostly at the 2nd~4th leaf order in all species besides Mar. indica. We found that the leaf order at which a leaf reached Amax in various seasons was influenced by both the leaf age when physiologically mature and the leaf sprouting rate during that season. A species would have leaves reached Amax at an front position of a branch when a shorter time is needed for reaching Amax. During a faster sprouting season, leaf order of reaching Amax would be at a position relatively away from the branch tip. However, leaf sprouting rates were slower during winter season such that leaves of physiologically mature would be at an front position. In addition, we also found that leaf age of leaf reaching Amax were the shortest during spring or summer seasons. Five species showed the longest leaf age of leaf reaching Amax during winter season, while that of H. littoralis and D. littoralis were during the spring season. For leaf sprouting rates, B. papyrifera, P. serratifolia, and Mar. indica grew 5~9 new leaves per month during spring and summer seasons; Mic. formosana, and H. littoralis grew 3 new leaves; and G. aequoreum and D. littoralis grew 2~3 leaves. To summarize results from the above 7 species, we found that leaves of a same branch reached Amax mostly at 3~5 leaf orders. In addition, leaves reached the highest photosynthetic capacity were at the front 1/4 position and not at the middle position of a branch. Keywords：leaf age, leaf generating speed, leaf order, maximum photosynthetic rate, seasonal variation.
48
Tsai, Yi-Tsung, and 蔡易璁. "The Assignment of Multi-site Order for Maximum Profit – A Case of a TFT-LCD Company." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/ne54y4.
Full textAbstract:
碩士中原大學
工業工程研究所
98
The present Cell process of TFT-LCD industry does not open product up to china in Taiwan, therefore Cell process is building in Taiwan, but the module’s factory and the customer’s system factory are located in China. The TFT-LCD industry become a multi-site production enterprises. Therefore how does produce under the multi-site and obtains the maximum profit base on the appropriate allocation, the theme will be discussed in this research. As China’s geopolitical vast, shipping cost is an important factor in china. Therefore, this study will be discuss the cost of production and transportation costs, Select the appropriate production of the factory . In this study, the establishment of a factory to consider the cost differences between different products. User the Linear Programming to solve of production capacity problem. After the examples of calculations show orders allocation model applied to TFT-LCD on the distribution of orders, and get approximate optimal solution.
49
Mehmetoglu, Orhan. "Stability and Convergence of High Order Numerical Methods for Nonlinear Hyperbolic Conservation Laws." Thesis, 2012. http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11653.
Full textAbstract:
Recently there have been numerous advances in the development of numerical algorithms to solve conservation laws. Even though the analytical theory (existence-uniqueness) is complete in the case of scalar conservation laws, there are many numerically robust methods for which the question of convergence and error estimates are still open. Usually high order schemes are constructed to be Total Variation Diminishing (TVD) which only guarantees convergence of such schemes to a weak solution. The standard approach in proving convergence to the entropy solution is to try to establish cell entropy inequalities. However, this typically requires additional non-homogeneous limitations on the numerical method, which reduces the modified scheme to first order when the mesh is refined. There are only a few results on the convergence which do not impose such limitations and all of them assume some smoothness on the initial data in addition to L^infinity bound.
The Nessyahu-Tadmor (NT) scheme is a typical example of a high order scheme. It is a simple yet robust second order non-oscillatory scheme, which relies on a non-linear piecewise linear reconstruction. A standard reconstruction choice is based on the so-called minmod limiter which gives a maximum principle for the scheme. Unfortunately, this limiter reduces the reconstruction to first order at local extrema. Numerical evidence suggests that this limitation is not necessary. By using MAPR-like limiters, one can allow local nonlinear reconstructions which do not reduce to first order at local extrema. However, use of such limiters requires a new approach when trying to prove a maximum principle for the scheme. It is also well known that the NT scheme does not satisfy the so-called strict cell entropy inequalities, which is the main difficulty in proving convergence to the entropy solution.
In this work, the NT scheme with MAPR-like limiters is considered. A maximum principle result for a conservation law with any Lipschitz flux and also with any k-monotone flux is proven. Using this result it is also proven that in the case of strictly convex flux, the NT scheme with a properly selected MAPR-like limiter satisfies an one-sided Lipschitz stability estimate. As a result, convergence to the unique entropy solution when the initial data satisfies the so-called one-sided Lipschitz condition is obtained. Finally, compensated compactness arguments are employed to prove that for any bounded initial data, the NT scheme based on a MAPR-like limiter converges strongly on compact sets to the unique entropy solution of the conservation law with a strictly convex flux.
50
Chen, Yi-Zhen, and 陳怡蓁. "Using Branch and Bound Algorithm and Minimum Cost Maximum Flow for Maximizing Committed Order Quantities Under Minimum Holding Cost." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/6x8ubv.
Full textAbstract:
碩士國立中央大學
工業管理研究所
107
Recently, the available-to-promise (ATP) function becomes critical in supply chain management, since it provides appropriate links between production resources and customer orders. In this research, company environment with n demands and m supplies is considered. It is assumed that the total quantity of demands are larger than that of supplies. Batch available-to-promise (batch ATP) and backward consumption mode are applied to commit order promise and fulfillment. Orders are collected periodically, then pegging is at a particular time point in order to find out which order can be promised. The company cannot commit all of demands because the total supplies are smaller than demands which is our assumption. Thus we need to schedule the priority of these orders to find out which order can be accepted or rejected, and the total of accepted demands are then obtained. The company objective is maximizing the committed quantities under minimum inventory holding cost. In order to get the optimal solution for this problem, we present a branch and bound algorithm and the minimum cost maximum flow to get maximum committed quantities.