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1
Assavapokee, Tiravat. "Semi-Continuous Robust Approach for Strategic Infrastructure Planning of Reverse Production Systems." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/7945.
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Growing attention is being paid to the problem of efficiently designing and operating reverse supply chain systems to handle the return flows of production wastes, packaging, and end-of-life products. Because uncertainty plays a significant role in all fields of decision-making, solution methodologies for determining the strategic infrastructure of reverse production systems under uncertainty are required. This dissertation presents innovative optimization algorithms for designing a robust network infrastructure when uncertainty affects the outcomes of the decisions. In our context, robustness is defined as minimizing the maximum regret under all realization of the uncertain parameters. These new algorithms can be effectively used in designing supply chain network infrastructure when the joint probability distributions of key parameters are unknown. These algorithms only require the information on potential ranges and possible discrete values of uncertain parameters, which often are available in practice. These algorithms extend the state of the art in robust optimization, both in the structure of the problems they address and the size of the formulations. An algorithm for dealing with the problem with correlated uncertain parameters is also presented. Case studies in reverse production system infrastructure design are presented. The approach is generalizable to the robust design of network supply chain systems with reverse production systems as one of their subsystems.
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Šandera, Čeněk. "Heuristické algoritmy pro optimalizaci." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228326.
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Práce se zabývá určením pravděpodobnostních rozdělení pro stochastické programování, při kterém jsou optimální hodnoty účelové funkce extrémní (minimální nebo maximální). Rozdělení se určuje pomocí heuristických metod, konkrétně pomocí genetických algoritmů, kde celá populace aproximuje hledané rozdělení. První kapitoly popisují obecně matematické a stochastické programování a dále jsou popsány různé heuristické metody a s důrazem na genetické algoritmy. Těžiště práce je v naprogramování daného algoritmu a otestování na úlohách lineárních a kvadratických stochastických modelů.
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Mendoza, Douglas M. "Generalized approach to minimal uncertainty products." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/83805.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2013.Cataloged from PDF version of thesis.
Includes bibliographical references (page 35).
A general technique to construct quantum states that saturate uncertainty products using variational methods is developed. Such a method allows one to numerically compute uncertainties in cases where the Robertson-Schrodinger (RS) uncertainty approach fails. To demonstrate the limitations of the RS approach, the ([Delta]x2 )([Delta]p) relation is examined using both the variational and direct method.
by Douglas M. Mendoza.
S.B.
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Löfberg, Johan. "Minimax Approaches to Robust Model Predictive Control." Doctoral thesis, Linköpings universitet, Reglerteknik, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-98168.
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Controlling a system with control and state constraints is one of the most important problems in control theory, but also one of the most challenging. Another important but just as demanding topic is robustness against uncertainties in a controlled system. One of the most successful approaches, both in theory and practice, to control constrained systems is model predictive control (MPC). The basic idea in MPC is to repeatedly solve optimization problems on-line to find an optimal input to the controlled system. In recent years, much effort has been spent to incorporate the robustness problem into this framework. The main part of the thesis revolves around minimax formulations of MPC for uncertain constrained linear discrete-time systems. A minimax strategy in MPC means that worst-case performance with respect to uncertainties is optimized. Unfortunately, many minimax MPC formulations yield intractable optimization problems with exponential complexity. Minimax algorithms for a number of uncertainty models are derived in the thesis. These include systems with bounded external additive disturbances, systems with uncertain gain, and systems described with linear fractional transformations. The central theme in the different algorithms is semidefinite relaxations. This means that the minimax problems are written as uncertain semidefinite programs, and then conservatively approximated using robust optimization theory. The result is an optimization problem with polynomial complexity. The use of semidefinite relaxations enables a framework that allows extensions of the basic algorithms, such as joint minimax control and estimation, and approx- imation of closed-loop minimax MPC using a convex programming framework. Additional topics include development of an efficient optimization algorithm to solve the resulting semidefinite programs and connections between deterministic minimax MPC and stochastic risk-sensitive control. The remaining part of the thesis is devoted to stability issues in MPC for continuous-time nonlinear unconstrained systems. While stability of MPC for un-constrained linear systems essentially is solved with the linear quadratic controller, no such simple solution exists in the nonlinear case. It is shown how tools from modern nonlinear control theory can be used to synthesize finite horizon MPC controllers with guaranteed stability, and more importantly, how some of the tech- nical assumptions in the literature can be dispensed with by using a slightly more complex controller.
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Cavanaugh, Kevin J. "A multilevel approach to minimal cost network flows." Thesis, Monterey, California. Naval Postgraduate School, 1992. http://hdl.handle.net/10945/23972.
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This thesis presents an exploration of the application of multigrid/multilevel techniques to a non-geometriclongtransportationproblem. Anintroductiontomultigrid is given, and specifics of how it is applied to this minimum cost network flow problem are explored.
This research shows that multilevel techniques can be applied to network optimization problems. Further, since a previous restriction is removed by transferring the problem from a physical space to a cost space, the techniques can be applied to a broader range of problems.
Both a multilevel V-cycle and a Full Multigrid (FMG) algorithm are implemented. Various strategies for restriction and local relaxation are discussed, and comparisons between the methods are made. Experimental results are given. Directions for future work include investigation of graph theoretic aspects of the problem, implementation of a regular grid overlay of the domain, exploration of a fast adaptive composite (FAC) grid algorithm, and development of a full approximation scheme (FAS) algorithm.
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Ferrara, Silvia. "An interdisciplinary approach to the Cypro-Minoan script." Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1446435/.
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The decipherment of Linear B in 1952 raised the possibility for further decipherments among the Aegean scripts. This unrealised prospect has coloured studies hitherto published on the Cypro-Minoan script with the result that there has been no large-scale systematic study that has employed a pragmatic and exhaustive perspective with a view to establishing a corpus and a critical re-assessment of the applicability of a decipherment method. This thesis aims at filling such a lacuna and responds to the need for a systematic analysis of the script through a corpus of all the inscriptions, here in Volume II (Catalogue) and a full analysis, in Volume I (Text), of the script from historical, archaeological, epigraphic and palaeographical perspectives. The historical conditions for the birth of literacy in Cyprus at the beginning of the Late Bronze Age are investigated in Chapter I, and are founded on a model that considers the material aspect of writing (script as part of the archaeological record, the extent of literacy, the geographical distribution of the inscriptions, the geo-political configuration of Cyprus, the concept of complexity), the functionality of the script (ideological and/or utilitarian applications), and also the symbolic aspect, linked to the realm of status representation and to the relationships between the various socio-political institutions involved in the creation of writing. From an interpretative perspective, the appearance of the script is examined in its symbolic manifestations, politically motivated and hierarchically marked within the manipulation of ideological significata. Following from the analysis of the distribution of the inscriptions, the archaeological investigation in Chapter 2 aims at establishing the relationship between Enkomi---which yielded the great majority of the inscriptions---and the other urban centres, in Cyprus and beyond, in which Cypro-Minoan was discovered. The script is considered in its different strategic significances, marked by a high level of regionalism within the power dynamics of the complex societies of Late Bronze Age Cyprus. Despite the uneven (or altogether absent) information offered by the extant publications as to the contextual associations and strata of many inscribed objects, a survey of how the script was used in each centre is proposed as well as a tentative interpretation of the function of the enigmatic clay bottles. The current classification of the inscriptions into three separate subgroups, CM1, CM2, CM3 (each allegedly hiding a different language), is critiqued in Chapter 3 and its invalidity is established through a review of its divisive, contradictory principles. The inscriptions are thus analysed from a new epigraphic dimension: the extent of ductus variation is seen in its close relationship to the wide range of typological classes of inscribed objects, and the scribal practices are analysed through a detailed study of all inscriptions that encompasses variability of reading direction, opisthography, pleurography, sematography, and metrology. In this respect, the role played by the Near Eastern writing traditions is assessed. Chapter 4 is dedicated to the palaeography of the script. The contributions to the study of this discipline with regard to Cypro-Minoan are appraised. The signary requires a formal rationalisation. The tripartite division has led to a fragmentary view of the script, and the present high level of palaeographical variation of the signs must be re-evaluated. The Cypro-Minoan syllabary as it stands, must be reduced if it is not to be disassociated from its Aegean lineage in which an open syllable configuration is prominent. Through a statistical frequency assessment of each discrete sign in its relative word-position (initial, medial and final) corroborated by the analysis of the significant sequences in which the sign is attested, possible assimilations of isographs with similar word-distributions are suggested. The palaeographical study further dissolves the tripartite classification and achieves a cohesive appreciation of the script.
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Löfberg, Johan. "Minimax approaches to robust model predictive control / Johan Löfberg." Linköping : Univ, 2003. http://www.bibl.liu.se/liupubl/disp/disp2003/tek812s.pdf.
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Na, Byungsoo. "Heurisic approaches for no-depot k-traveling salesmen problem with a minmax objective." Texas A&M University, 2003. http://hdl.handle.net/1969.1/5825.
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This thesis deals with the no-depot minmax Multiple Traveling Salesmen Problem
(MTSP), which can be formulated as follows. Given a set of n cities and k salesmen,find k disjoint tours (one for each salesmen) such that each city belongs to exactly one
tour and the length of the longest of k tours is minimized. The no-depot assumption
means that the salesmen do not start from and return to one fixed depot. The no-depot model can be applied in designing patrolling routes, as well as in business
situations, especially where salesmen work from home or the company has no central
office. This model can be also applied to the job scheduling problem with n jobs and
k identical machines.
Despite its potential applicability to a number of important situations, the research literature on the no-depot minmax k-TSP has been limited, with no reports
on computational experiments. The previously published results included the proof
of NP-hardness of the problem of interest, which motivates using heuristics for its
solution. This thesis proposes several construction heuristic algorithms, including
greedy algorithms, cluster first and route second algorithms, and route first and cluster second algorithms. As a local search method for a single tour, 2-opt search and
Lin-Kernighan were used, and for a local search method between multiple tours,
relocation and exchange (edge heuristics) were used. Furthermore, to prevent the
drawback of trapping in the local minima, the simulated annealing method is used. Extensive computational experiments were carried out using TSPLIB instances.
Among construction algorithms, route first and cluster second algorithms including
removing two edges method performed best. In terms of running time, clustering
first and routing second algorithms took shorter time on large-scale instances. The
simulated annealing could produce better solutions than the descent method, but did
not always perform well in terms of average solution. To evaluate the performance
of the proposed heuristic methods, their solutions were compared with the optimal
solutions obtained using a mixed-integer programming formulation of the problem.
For small-scale problems, heuristic solutions were equal to the optimal solution output
by CPLEX.
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Brueni, Dennis J. "Minimal PMU placement for graph observability : a decomposition approach /." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-10312009-020314/.
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Iwamura, Rafael Santos. "Minimax approach applied to topology optimization of structures subjected to multiple load cases." Instituto Tecnológico de Aeronáutica, 2013. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=2834.
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This work investigates a topology optimization strategy for structures under multiple load cases. Typically compliance is calculated for each of the load cases in analysis and minimization is computed for a weighted average of the compliances, resulting in time consuming algorithms. A way to increase convergence speed is updating density on the element level. Instead of having an averaged compliance for the whole structure, it is proposed to compute it individually for every element. All load cases are analyzed, however only the ones of the maximum compliances are considered for sensitivity analysis. Thus compliance gradient is function of a few load cases at each element, reducing the processing time without significant weight penalty. The efficiency of the proposed technique is exemplified and compared to the one of a classical approach of multiple load case problem, solved using optimality criteria.
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Hubrich, Hanna. "Active Matter in Confined Geometries - Biophysics of Artificial Minimal Cortices." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-152A-5.
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McKenzie-Young, Rebecca. "The role of women in Minoan Crete : a historiographic approach." Thesis, University College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.417687.
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Berry, Robert D. "A New Approach to Lie Symmetry Groups of Minimal Surfaces." BYU ScholarsArchive, 2004. https://scholarsarchive.byu.edu/etd/321.
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The Lie symmetry groups of minimal surfaces by way of planar harmonic functions are determined. It is shown that a symmetry group acting on the minimal surfaces is isomorphic with H × H^2 — the analytic functions and the harmonic functions. A subgroup of this gives a generalization of the associated family which is examined.
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Papalaskari, Mary-Angela. "Minimal consequence : a semantic approach to reasoning with incomplete information." Thesis, University of Edinburgh, 1988. http://hdl.handle.net/1842/19214.
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D'Silva, Karl. "Two Approaches to the Isotonic Change-Point Problem: Nonparametric and Minimax." Diss., North Dakota State University, 2014. https://hdl.handle.net/10365/27402.
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A change in model parameters over time often characterizes major events. Situations in which this may arise include observing increasing temperatures, intense rainfall, and the valuation of a stock. The question is whether these observations are simply the result of natural variation, or rather are indicative of an underlying monotonic trend. This is known as the isotonic change-point problem. Two approaches to this problem are considered: Firstly, for correlated data with short-range dependence, we prove that a particular U-statistic based on a modified version of the Jonckheere-Terpstra test statistic is asymptotically equivalent to a more complex U-statistic discussed by Shen and Xu (2013); one that has been shown to outperform other existing tests in a variety of situations. Secondly, we shall justify and utilize the minimax criterion in order to identify the optimal test statistic within a specified class. We shall see that, as motivated by the projection method, the aforementioned class is the class of contrasts. It shall be proven that the set of coefficients originally proposed by Abelson and Tukey (1963), and utilized by Brillinger (1989) in the isotonic change-point setting, are in fact minimax in the independent data case. For correlated data with shortrange dependence, we shall demonstrate a sufficient condition for minimaxity to hold.
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Andrews, Stuart. "Interactive generation of feature contours on surfaces, a minimal paths approach." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0016/MQ49735.pdf.
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Rabin, Samuel. "A variational approach to determining nonlinear optimal perturbations and minimal seeds." Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648503.
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Bougaïeff, Nicolas. "An approach to composition based on a minimal techno case study." Thesis, University of Huddersfield, 2013. http://eprints.hud.ac.uk/id/eprint/18067/.
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This dissertation examines key issues relating to minimal techno, a sub-genre of electronic dance music (EDM) that emerged in the early 1990s. These key issues are the aesthetics, composition, performance, and technology of minimal techno, as well as the economics of EDM production. The study aims to answer the following question. What is the musical and social significance of minimal techno production and performance? The study is conducted in two parts. The history of minimal music is traced from Satie in the 1890s to Plastikman in the 1990s, a central contribution to minimal techno. Plastikman is a stage name for the subject of the first part, a case study of minimal techno artist Richie Hawtin. A chapter on Liine, a company I founded with partners including Richie Hawtin, describes the performance software we developed for his 2010-2011 Plastikman Live tour. A chapter on minimal techno performance methods examines the structure of the Ableton Live set created for Plastikman Live. A theory chapter, based on Jacques Attali’s Bruits (2001), studies the relationship between technology, money, power and techno music production on both an individual and collective scale. The second part provides a detailed commentary on music I composed during the project in response to the theoretical issues raised. A final chapter discusses the overall thesis, and draws conclusions. Minimal techno, as it is practiced through Liine software, the Plastikman Live show, or through my own productions, is revealed to be a deeply improvisatory form of music. The relationship between body, mind and sound emerges as one of the major themes. Minimal techno production and performance can be seen as a reflection of the profoundly changing relationship between man and digital technology.
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Zhao, Boning. "A THEORETIC APPROACH FOR BINARY GAME TREE EVALUATION." Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1586520140611046.
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Day, Peter Martin. "A petrographic approach to the study of pottery in neopalatial East Crete." Thesis, University of Cambridge, 1991. https://www.repository.cam.ac.uk/handle/1810/273143.
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Jeanjean, Louis. "Approche minimax des solutions d'une équation semi-linéaire elliptique en l'absence de compacité /." [S.l.] : [s.n.], 1992. http://library.epfl.ch/theses/?nr=1041.
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Vasilic, Isabelle. "La Chose et l'art minimal : une approche du réel." Thesis, Montpellier 3, 2020. http://www.theses.fr/2020MON30036.
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Les objets spécifiques de Donald Judd font symptôme dans le discours de l'art. Ces œuvres valorisent la dimension du vide et exacerbent le réel. L'enjeu phénoménologique qui caractérise cet art se vérifie dans les dispositifs immersifs où le spectateur est renvoyé à une expérience active où il perçoit son corps comme réalité physique. L'art minimal intéresse la psychanalyse car il peut venir éclairer le concept freudien de das Ding. Cette Chose relève d'un enjeu clinique et éthique majeur : elle est au fondement de l'Autre préhistorique, absolu du sujet. Lacan dira « Ce qui pâtit du signifiant ». Un dam qui orientera le sujet dans sa rencontre avec le réel, son être de jouissance. Nous examinerons la Chose comme un nom du réel dans les champs artistiques et philosophiques où nous convoque l'art minimal. La choséité de Heidegger et l'ontologie de la chair de Merleau-Ponty seront mises à l'épreuve du corps pulsionnel et de l'objet a regard. Objet cause du désir, paradigme de la schize du parlêtre nous démontrerons qu'il procède de la Chose. Celle-ci oeuvrant derrière l'objet. La création dans ses liens aux questions attenantes à la structure, à ses incidences cliniques enseignent la psychanalyse : jouissance nocive, récupération de jouissance ? L'artiste répond de sa division subjective en créant une œuvre et par là restaure la dimension du trou au-delà de l'objet : sublimation artistique, pratique de la lettre, savoir-y-faire avec le réel. Le symptôme recèle un réel qui commande l'existence du sujet : das Ding.Mots clefs : das Ding, réel, jouissance, art minimal, objet a regard, phénoménologieTitle : The Thing and minimal art : an approach of the realDonald Judd's specific objects are symptomatic of the discourse surrounding art. These works enhance the dimension of emptiness and exacerbate the real. The phenomenological issues which characterize this art are verified in immersive devices where the spectator is retumed to an active experience in which he perceives his body as a physical reality. Minimal art is of interest to psychanalysis because it can shed light on Freud's concept of das Ding. This Thing raises a major clinical and ethical problem : it is a foundation of the prehistorical Other, the absolute subject. Lacan says : « what suffers from the signifier ». A prejudice which will point the way for the subject into a meeting with the real, his existence of pleasure. We will examine the Thing as a name for the real in artistical and philosophical fields in which minimal art concerns us. Heidegger's thingness and Merleau-Ponty ontology of the flesh will be challenged by the instinctual body and the object in view. Object as cause of desire, paradigm of the shize of the speaking being, we will demonstrate that it proceeds from the Thing, the latter working behind the object. Creation in its links to questions concerning the structure, to its clinical incidents that inform psychanalysis : harmful pleasure, or the recuperation of pleasure ? The artist responds to his subjective division by creating a work and thereby restoring the dimension of the gap beyond the object : artistic sublimation, practice of words, a knowhow of the real. The symptom conceals a real which orders the existence of the subject : das Ding .Keys words : das Ding, real, pleasure, minimal art, object in view, phenomenology
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Hankinson, Colin. "An evaluation of the learning styles approach to education : a minimal intervention strategy." Thesis, University of Manchester, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488159.
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This research is in essence two separate pieces of work: (1) It is a traditional empirical piece of research evaluating the learning styles approach to education. (2) It considers the value of utilising the postmodern paradigm of chaos theory to argue for a synthesis incorporating learning (and by generalisation educational theory as a whole) with chaos theory, via neurological positivism. However, both (1) and (2) above overlap and interact on a theoretical philosophical plane. It should also be noted that the main research direction of this thesis is towards a traditional empirical study of the learning styles approach to education. The work on chaos theory is secondary to this and seeks to offer a theoretical philosophical rationale for the enrichment of educational theory as a whole, by linking traditional beliefs to postmodern concepts. The primary aim of this research was to evaluate the Learning Styles Approach to Education, and in particular the nature of the minimal intervention required to produce a significant positive result in relation to student educational performance. The secondary aim was a more global theoretical one i.e. to argue for a synthesis incorporating learning (and by generalisation educational theory as a whole), with chaos theory, via Vandervert's (1988, 1997) 'neurological positivism'. A diagram was developed by the author to illustrate this theoretical synthesis (section 2. 32). In the main study the experimental hypothesis was as follows: Student's knowledge of their own Learning Style Profile will have a positive effect upon their educational performance, even when the educational environment has not been adapted to cater for individual learning style requirements', The independent variable is the feedback on the participant's own Learning Style Profile score, and the dependent variable is the course scores obtained by the participants at pre-test and post-test. The participants consisted of an experimental group (n = 130) and a control group (n = 126) all students at Stockport College of Further & Higher Education. The National Association of Secondary School Principals (NASSP) Learning Style Profile was administered to each member of the experimental , group and the results explained to each member individually. At no time was the educational environment adapted in any way to cater for the participant's individual learning style needs. All the participants pre-test and post-test course scores were collected and mean improvement scores calculated and compared. The results indicated a significant 'group' by 'mean improvement' score
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Strack, Robert. "Geometric Approach to Support Vector Machines Learning for Large Datasets." VCU Scholars Compass, 2013. http://scholarscompass.vcu.edu/etd/3124.
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The dissertation introduces Sphere Support Vector Machines (SphereSVM) and Minimal Norm Support Vector Machines (MNSVM) as the new fast classification algorithms that use geometrical properties of the underlying classification problems to efficiently obtain models describing training data. SphereSVM is based on combining minimal enclosing ball approach, state of the art nearest point problem solvers and probabilistic techniques. The blending of the three speeds up the training phase of SVMs significantly and reaches similar (i.e., practically the same) accuracy as the other classification models over several big and large real data sets within the strict validation frame of a double (nested) cross-validation (CV). MNSVM is further simplification of SphereSVM algorithm. Here, relatively complex classification task was converted into one of the simplest geometrical problems -- minimal norm problem. This resulted in additional speedup compared to SphereSVM. The results shown are promoting both SphereSVM and MNSVM as outstanding alternatives for handling large and ultra-large datasets in a reasonable time without switching to various parallelization schemes for SVMs algorithms proposed recently. The variants of both algorithms, which work without explicit bias term, are also presented. In addition, other techniques aiming to improve the time efficiency are discussed (such as over-relaxation and improved support vector selection scheme). Finally, the accuracy and performance of all these modifications are carefully analyzed and results based on nested cross-validation procedure are shown.
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Gayraud, Ghislaine. "Vitesses et procédures statistiques minimax dans des problèmes d'estimation et des tests d'hypothèses." Habilitation à diriger des recherches, Université de Rouen, 2007. http://tel.archives-ouvertes.fr/tel-00207687.
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Mes travaux s'articulent autour de trois thématiques. La première thèmatique porte sur la résolution via l'approche minimax de divers problèmes d'estimation et de tests d'hypothèses dans un cadre non-paramétrique.
En statistique Bayésienne non-paramétrique, je me suis intéressée à un problème d'estimation d'ensembles à niveau. Les résultats obtenus résultent de l'étude des propriétés asymptotiques d'estimation Bayésienne d'ensembles à niveau. Ce sont des résultats généraux au sens où la consistance et la vitesse de convergence de l'estimateur Bayésien sont établies pour une large classe de lois a priori.
La troisième thématique concerne un problème d'estimation paramétrique dans un modèle de déconvolution aveugle bruitée : il s'agit de restituer la loi du signal entrant. La consistance ainsi que la distribution asymptotique d'une nouvelle procédure d'estimation sont établies.
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Richardson, Gwendolen M. "Cognitive-behavioral therapy for the treatment of headaches diagnosed as common migraine a minimal-therapist-contact approach versus a clinic-based approach." Thesis, University of Ottawa (Canada), 1988. http://hdl.handle.net/10393/5115.
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Zhang, Lei. "Minimal-Disturbance Rehabilitation Technique for Improving Seismic Performance of Existing Steel Moment-Frame Buildings." Kyoto University, 2017. http://hdl.handle.net/2433/227620.
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Comminges, Laëtitia. "Quelques contributions à la sélection de variables et aux tests non-paramétriques." Thesis, Paris Est, 2012. http://www.theses.fr/2012PEST1068/document.
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Les données du monde réel sont souvent de très grande dimension, faisant intervenir un grand nombre de variables non pertinentes ou redondantes. La sélection de variables est donc utile dans ce cadre. D'abord, on considère la sélection de variables dans le modèle de régression quand le nombre de variables est très grand. En particulier on traite le cas où le nombre de variables pertinentes est bien plus petit que la dimension ambiante. Sans supposer aucune forme paramétrique pour la fonction de régression, on obtient des conditions minimales permettant de retrouver l'ensemble des variables pertinentes. Ces conditions relient la dimension intrinsèque à la dimension ambiante et la taille de l'échantillon. Ensuite, on considère le problème du test d'une hypothèse nulle composite sous un modèle de régression non paramétrique multi varié. Pour une fonctionnelle quadratique donnée $Q$, l'hypothèse nulle correspond au fait que la fonction $f$ satisfait la contrainte $Q[f] = 0$, tandis que l'alternative correspond aux fonctions pour lesquelles $ |Q[f]|$ est minorée par une constante strictement positive. On fournit des taux minimax de test et les constantes de séparation exactes ainsi qu'une procédure optimale exacte, pour des fonctionnelles quadratiques diagonales et positives. On peut utiliser ces résultats pour tester la pertinence d'une ou plusieurs variables explicatives. L'étude des taux minimax pour les fonctionnelles quadratiques diagonales qui ne sont ni positives ni négatives, fait apparaître deux régimes différents : un régime « régulier » et un régime « irrégulier ». On applique ceci au test de l'égalité des normes de deux fonctions observées dans des environnements bruitésReal-world data are often extremely high-dimensional, severely under constrained and interspersed with a large number of irrelevant or redundant features. Relevant variable selection is a compelling approach for addressing statistical issues in the scenario of high-dimensional and noisy data with small sample size. First, we address the issue of variable selection in the regression model when the number of variables is very large. The main focus is on the situation where the number of relevant variables is much smaller than the ambient dimension. Without assuming any parametric form of the underlying regression function, we get tight conditions making it possible to consistently estimate the set of relevant variables. Secondly, we consider the problem of testing a particular type of composite null hypothesis under a nonparametric multivariate regression model. For a given quadratic functional $Q$, the null hypothesis states that the regression function $f$ satisfies the constraint $Q[f] = 0$, while the alternative corresponds to the functions for which $Q[f]$ is bounded away from zero. We provide minimax rates of testing and the exact separation constants, along with a sharp-optimal testing procedure, for diagonal and nonnegative quadratic functionals. We can apply this to testing the relevance of a variable. Studying minimax rates for quadratic functionals which are neither positive nor negative, makes appear two different regimes: “regular” and “irregular”. We apply this to the issue of testing the equality of norms of two functions observed in noisy environments
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Anton, Fernando. "Half-string oscillator approach to closed string field theory and superconformal minimal models on the torus." Thesis, University of Oxford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335904.
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Choley, Jean-Yves. "Une approche variationnelle de l'association des références en tolérancement géométrique." Châtenay-Malabry, Ecole centrale de Paris, 2005. http://www.theses.fr/2005ECAP0963.
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Lors de la conception d'un produit, la CAO permet de définir la géométrie nominale ainsi que le tolérancement géométrique spécifié pour chaque composant. L'analyse métrologique permet de s'assurer que les composants fabriqués sont conformes à ces spécifications. Pour cela, des références spécifiées sont associées en respectant les normes en vigueur. L'analyse approfondie de ces normes effectuée, les modèles SATT et GEOSPELLING sont abordés pour définir le tolérancement géométrique. De même, la comparaison des différents critères d'optimisation et l'étude des outils mathématiques applicables à l'association des références spécifiées se révèlent nécessaires, avant de développer une nouvelle démarche pour cette opération. Au lieu de déplacer la géométrie comme le font les méthodes couramment utilisées, les points mesurés sont considérés comme des perturbations qui provoquent une modification de la géométrie nominale par variation des paramètres d'orientation, de position et de dimensions intrinsèques et ce, sans faire appel à des variables "cinématiques" de rotation et de translation. La méthode repose sur une modélisation vectorielle de la géométrie et sur une fonction variationnelle d'écart et sa jacobienne. L'optimisation au sens des moindres carrés est alors obtenue à l'aide de la matrice pseudo-inverse. Le critère du minimax est traité, quant à lui, à l'aide d'un algorithme développé par le PTB et adapté en conséquence. Il est enfin précisé comment cette méthode d'association est applicable avec le critère des moindres carrés et le critère du minimax, pour des plans et des cylindres pris comme références simples, communes ou systèmes de référencesWhen it comes to designing a new product, CAD systems allow us to define the nominal geometry as well as to specify the geometrical tolerancing for each constituting part. The metrological analysis will check if the machined parts are in accordance with these specifications. To this end, specified datums are associated with respect to the current standards. A thorough analysis of these standards is then carried out. At this stage, the SATT and GEOSPELLING models are tackled in order to define the geometrical tolerancing. Likewise, it turns out to be necessary to both compare the different optimisation criteria and study the mathematical tools applying to the association of specified datums before developing a new reasoning for this operation. Instead of moving the geometry as the traditional methods usually do, measured points are considered as perturbations which generate modifications of the nominal geometry by variation of its orientation, location and intrinsic dimensional parameters, without requiring rotation and translation variables. The method is based on both a vectorial modelling of the geometry and a variational distance function as well as its jacobian. The least squares optimisation is then achieved using the pseudo-inverse matrix, whereas the minimax criterion is treated with an algorithm developed by the PTB and adapted on purpose. It is then explained how this association method may be applied to planes and cylinders, used as single datums, datums systems or common datums, with the least squares and minimax criteria
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Wright, Joseph H. "An Investigation of a Minimal-Contact Bibliotherapy Approach to Relapse Prevention for Individuals Treated for Panic Attacks." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/30686.
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The present study was designed to test the efficacy of a bibliotherapy-relapse prevention (BT-RP) program for panic attacks in which the active BT-RP condition was compared to a waiting-list control condition. Prior to the administration of the six-month BT-RP program, all participants completed an initial BT intervention (Febbraro, 1997) based on the book Coping with Panic (Clum, 1990). The BT-RP program was designed to: (a) review major components of the initial intervention; (b) increase practice of panic coping skills and therapeutic self-exposure; (c) enhance social support for panic recovery; (d) teach cognitive restructuring skills related to relapse prevention; (e) provide a protocol to follow in the event of a setback; and (f) reduce overall levels of stress. Brief monthly phone contacts were included in the BT-RP condition. Thirty-six participants, 17 in the BT-RP condition and 19 in the WL control condition, completed the study. A 2 (Treatment condition: BT-RP versus WL control) X 2 (Time: Pre-BT-RP assessment versus Post-BT-RP assessment) mixed-model research design was used to analyze the results. Results indicted significant reductions from pre- to post-treatment in the BT-RP condition for panic cognitions, anticipatory anxiety, agoraphobic avoidance, and depression, but not in the WL condition. When statistically controlling for initial levels of these variables via analyses of covariance (ANCOVAs), significant post-treatment differences in the expected direction emerged for these four dependent measure and for state anxiety. In addition, the BT-RP group reported significantly fewer panic attacks during the six-month course of the treatment trial than the WL control group on a measure of retrospective recall of full-blown panic attacks. There was also a
statistically significant proportional between-group difference in terms of clinically significant improvement for full-blown panic attacks and agoraphobic avoidance in favor of the BT-RP group. However, no significant between-group differences emerged for the maintenance of initial treatment gains for panic frequency, panic symptoms, panic cognitions, anticipatory anxiety, or agoraphobic avoidance. Results of the present study are discussed in the framework of benefits of the present BT-RP program, limitations of the findings, recommendations for future research in this area, and implications for BT treatments in general.Ph. D.
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Blom, Diana. "Minimal music roles and approaches of teachers engaging students with a contemporary art music through composing activities /." Connect to full text, 2001. http://hdl.handle.net/2123/802.
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Thesis (Ph. D.)--University of Sydney, 2002.Title from title screen (viewed Apr. 24, 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Dept. of Music, Faculty of Arts. Degree awarded 2002; thesis submitted 2001. Includes bibliography. Also available in print form.
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Ström, Lars. "Self-help via the Internet : A new approach to psychological treatment." Doctoral thesis, Uppsala University, Department of Psychology, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3592.
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During the last 30 years, studies have shown self-help to be effective in a number of areas, and to produce equal or close to equal results compared to face-to-face therapy. The Internet can reach a large number of people at a low cost and add the possibility of two-way communication to self-help, thereby offering cost-effective psychological treatments.
This thesis is based on four studies and aiming to investigate if self-help treatment conducted through Internet can reduce problems with insomnia, stress and headache and reach effect sizes comparable to previous minimal contact treatment studies. Other aims were to investigate cost-effectiveness, and to examine if adding regular telephone contact would reduce drop-out rates. Treatments involved psychological techniques previously proved to be effective for each problem.
The first study showed a significant decrease in headache severity, and 50% of the participants in the treatment condition showed a clinically significant improvement. In Study II an Internet-based stress management program resulted in significant reductions of perceived stress, anxiety and depression. Improvements were found in both groups, with stronger effects in the self-help treatment group. Study III, a sleep management program, resulted in statistically significant improvements in the treatment group on all main variables, including total sleep time, total wake time in bed, and sleep efficiency. Some improvements were also found in the control group. Follow-up data indicated that improvements were sustained. Study IV did not confirm the hypothesis that the drop-out rates during headache treatment should decrease significantly if adding short and regular telephone contacts.
Results from this thesis suggest that Internet is a medium well suited for therapy, with effect sizes comparable to face-to-face therapy, that using Internet as a medium for treatment can reduce costs while still maintaining similar results, and that adding a small amount of telephone contact does not decrease attrition.
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Blom, Diana Mary. "Minimal music: roles and approaches of teachers engaging students with a contemporary art music through composing activities." University of Sydney. Music, 2001. http://hdl.handle.net/2123/802.
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Since it arose in the 1960s, the minimalist aesthetic has increasingly influenced composers of art and popular music around the world and, in turn, minimalist composers have drawn on the compositional ideas of Western popular music and several non-Western musics. Educationally, minimal music offers much potential for music in the classroom as it embodies a number of musical characteristics known to, and preferred by, students aged 9-18 years at primary, secondary and first year tertiary level. Socially, it offers teachers an opportunity to engage students, through composing activities, with contemporary society. The study aims, firstly, to analyse compositions by students aged 9, 12, 15 and 18 years and their teachers, seeking pastiche development of, and compositional expansion beyond, the musical concepts presented in a resource booklet of projects, The Pulse Music Album. Secondly, this study aims to investigate how nineteen participating teachers in three countries engage their students with minimalist composing activities stimulated through the resource booklet. The study attempts to determine why teachers adopt their particular roles and strategies by examining music qualifications, preferences and experience, teaching perspectives and teaching environments. It also seeks to identify reasons why one group of teachers submitted pieces which were pastiches of those presented in the projects and another group submitted compositions which moved well beyond pastiche into an expansion of these same musical concepts and argues for this as evidence of dialogue with contemporary society. Conclusions drawn from the findings note that while there are many commonalities between the backgrounds and approaches of both groups of teachers, there are clearly observed differences. These differences suggest approaches to classroom composition for consideration by practising classroom teachers, in-service instructors and teacher training institutions.
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Blondeau-Fournier, Olivier. "Approche combinatoire des modèles minimaux en théorie des champs conformes : connexion avec les chemins sur réseau demi-entier." Thesis, Université Laval, 2010. http://www.theses.ulaval.ca/2010/27705/27705.pdf.
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Billion, André [Verfasser]. "Comparative transcriptomics of intracellular survival of Listeria : A bioinformatics approach to determine the minimal genome required for intracellular survival of Listeria monocytogenes / André Billion." Gießen : Universitätsbibliothek, 2014. http://d-nb.info/1068536780/34.
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Weiss, Marian [Verfasser], and Joachim [Akademischer Betreuer] Spatz. "Microfluidic Approaches for the Sequential Bottom-up Assembly of Droplet-based Minimal Synthetic Cells / Marian Weiss ; Betreuer: Joachim Spatz." Heidelberg : Universitätsbibliothek Heidelberg, 2018. http://d-nb.info/1177691485/34.
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Weiss, Marian [Verfasser], and Joachim P. [Akademischer Betreuer] Spatz. "Microfluidic Approaches for the Sequential Bottom-up Assembly of Droplet-based Minimal Synthetic Cells / Marian Weiss ; Betreuer: Joachim Spatz." Heidelberg : Universitätsbibliothek Heidelberg, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:16-heidok-240369.
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Mattos, Ely José de. "Pobreza rural no Brasil : um enfoque comparativo entre a abordagem monetária e a abordagem das capacitações." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2006. http://hdl.handle.net/10183/10803.
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Esta dissertação faz uma análise da pobreza rural no Brasil a partir de duas abordagens distintas. Uma delas, a mais tradicional, unidimensional, baseada exclusivamente na renda: a abordagem monetária. A outra, de natureza multidimensional, relativamente recente, baseada naquilo que as pessoas são capazes de ser e fazer: Abordagem das Capacitações, de Amartya Kumar Sen. A questão investigada neste trabalho é se as compreensões de pobreza rural fornecidas por cada uma destas abordagens diferem entre si. Para tal, foram utilizados dados secundários da Pesquisa Nacional por Amostra de Domicílios (PNAD/IBGE), trazendo, além do Brasil de forma agregada, os estados do Rio Grande do Sul (RS), Minas Gerais (MG) e Rio Grande do Norte (RN). Foram selecionados estes três estados, de regiões diferentes, para captar a heterogeneidade de realidades do país. Subliminar a esta problemática da comparação de abordagens estão duas contribuições específicas desta dissertação: o avanço na discussão sobre o entendimento da pobreza no meio rural e uma contribuição na consolidação da operacionalização da Abordagem das Capacitações a partir de dados secundários. Na parte teórica deste trabalho foram analisados os elementos centrais de cada uma destas abordagens, procurando dar embasamento para as métricas sob as quais se assentam as evidências empíricas de cada uma. A parte metodológica, que apresenta estas métricas, tem especial importância no caso da Abordagem das Capacitações, por se tratar de uma abordagem mais nova e ainda não consolidada. A abordagem monetária se baseia na renda domiciliar per capita, fazendo uso de ferramentas de análise que tratam da distribuição de renda, linhas monetárias de pobreza e de medidas de pobreza. Já a Abordagem das Capacitações analisa três funcionamentos (ser e fazer) específicos: estudo, saúde e mobilidade e condições de moradia. Isto é feito através de técnicas estatísticas multivariadas (Análise Fatorial e Análise de Cluster). Os resultados concernentes à abordagem monetária mostram uma combinação de renda média baixa e distribuição de renda consideravelmente assimétrica, o que desenha uma realidade de pobreza rural bastante específica. O RS é o estado que apresenta as melhores condições, e o RN o que apresenta as piores, entre eles estão MG e o Brasil como um todo. Já com relação às evidências empíricas da Abordagem das Capacitações, os resultados não permitem dizer que um estado está em melhores condições do que outro, de forma absoluta. Cada um tem características específicas, uma estrutura multidimensional particular em relação àqueles três funcionamentos. O RS tem melhores indicadores para o funcionamento moradia, por exemplo, enquanto MG tem melhores resultados para educação. Pode-se dizer que cada um tem estruturas de bem-estar diferenciadas, mas não que um seja mais “pobre” do que outro. Esta diferença de resultados entre as abordagens está associada a uma diferença de percepção do fenômeno pobreza. O próprio papel desempenhado pela renda, cabe salientar, é diferente no contexto da Abordagem das Capacitações: sua influência sobre as dimensões estudadas não apresenta um padrão claro. Os resultados empíricos, portanto, são diferentes porque a percepção que se tem do fenômeno é diversa.This master thesis presents an analysis of the rural poverty in Brazil based on two different approaches. One of them, more traditional, unidimensional, exclusively based on income: the monetary approach. The other one, relatively recent, multidimensional, based on what people are able to do or to be: the Capability Approach, proposed by Amartya Kumar Sen. The question investigated throughout this study is if the comprehensions of rural poverty offered by these two approaches point out in different ways or not. To take it forward, it was used secondary data from the National Household Sample Survey (PNAD/IBGE). And the study analyzes Brazil, as a whole, and three states: Rio Grande do Sul (RS), Minas Gerais (MG) and Rio Grande do Norte (RN). It was selected states from different regions of the country aiming to capture the heterogeneities of realities in Brazil. Underlying to the question of comparing the two approaches are a pair of specific topics in which the present study goes on: an advance on the debate about rural poverty and a contribution for the consolidation of the operationalization of the Capability Approach based on secondary data. The theoretical section of the master thesis analyzes the central elements of each approach, trying to establish the basis on which the empirical metrics are settled. The methodological section presents those metrics and it is especially important in the case of the Capability Approach, because of its peculiarity of being a new approach and not yet consolidated. The monetary approach is based on the household income per capita, and uses analysis tools that count on the income distribution, monetary poverty lines and poverty measures. The Capability Approach, in turn, analyses three different functionings (beings and doings): study, health and mobility, and housing conditions. That analysis is performed through multivariate statistical techniques (Factor Analysis and Cluster Analysis). The results concerning the monetary approach point out a combination of low income average and asymmetric income distribution which draw a specific reality of rural poverty. The state of RS presents the best conditions in terms of those monetary indicators, and the state of RN the worse. Between RS and RN are Brazil as a whole and the state of MG. The empirical evidences from the Capability Approach, however, do not allow saying that one state is better off than another one in an absolute way. Each state has specific characteristics, has a particular multidimensional structure regarding those three functionings. The state of RS presents the best indicator in housing conditions, for instance, whereas MG offers the best result in education. It is possible to say that each state has different structures of well-being, but we cannot say that one state is “poorer” than another one. Those differences between the two approaches, in terms of empirical results, are related to a diverse perception of the phenomenon named poverty. Even the role played by income is different in the context of the Capability Approach: its influence over the dimensions investigated does not present any clear pattern. Summarizing, the empirical results are different because the perception of poverty is diverse.
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Vieira, Lívia Maria Fraga. "Éducation de la petite enfance dans la législation éducationnelle brésilienne du XXème siècle : approche historique de l'Etat de Minas Gerais (1908-2000)." Paris 5, 2006. http://www.theses.fr/2006PA05H096.
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Dans cette thèse nous voulons étudier l'histoire des politiques d'éducation de la petite enfance au Brésil, en faisant ressortir, par l'examen de la législation éducationnelle, les principes directeurs de l'action publique pour mettre en place l'offre institutionnelle publique des écoles infantiles. Nous voulons aussi mettre en relief les dynamiques de cette offre institutionnelle proposée par les pouvoirs publics liés au secteur de l'éducation tout au long du XXeme siècle, notamment dans le contexte particulier d'une unité fédérale, l'état de Minas Gérais, situé au sud-est brésilien. Dans une perspective longitudinale, nous avons travaillé sur la législation concernant le système éducatif produite sur le plan fédéral, sur le plan de l'État du Minas Gérais et dans les instances du législatif et de l'exécutif, en tant que source privilégiée, pour étudier les politiques publiques de l'éducation infantile, conçues comme un « système d'action » où sont impliqués plusieurs éléments. On cherche à étudier et à analyser la façon dont le secteur éducatif a conçu, fondé, réglé et mis en œuvre, par le truchement de ses instruments légaux, les institutions et les organismes spécifiques, les politiques et les programmes concernant l'éducation des enfants avant l'âge de l'éducation élémentaire obligatoire dans des jardins d'enfants, écoles maternelles et classes infantiles. Dans le secteur éducationnel, nous avons privilégié l'action des pouvoirs publics. Nous apportons des conclusions sur les stratégies dominantes de l'offre institutionnelle, sur les objectifs aussi bien que sur les responsabilités publiques et parentalesIn this dissertation, we have stuied how the politics of earlychildhood education has been established in Brazil, through an analysis of educational law and the principles which have driven activism for the implementation of public and free preschools in that country. We have also tried to show the very dynamic of how public earlychildhood education has been offered in Brazil, during the 20th century, focusing specifically upon the case of one Brazilian state : the state of Minas Gerais, at the southeast region of Brazil. Through a longitudinal study, we have focused upon both the federal and the state of Minas Gerais educational legislation as a source to analyse how the public politics on earlychildhood education have been seen as a « system of action. » Hence, at this academic work, we have sought to study and analyse how the Brazilian educational sector, through its legal mechanisms, has seen, established, and regulated the specific institutions, politics, and programs regarding earlychildhood education. At the educational sector, we have focused upon the initiaves as well as the public educational institutions and programs that came out from the sphere of state. As a conclusion, we have highlighted the aspects related to objectives, to parents and public responsibilities, and to the dominant strategies for offering public earlychildhood education in Brazil
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Tsikritea, Vasiliki. "Beyond Decoration: A Social Approach to Inclusion and Exclusion of Textile Motifs from LM IA LM IIIA1 Pottery." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1539080491763967.
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Bouvier-Joly, Catherine. "Une approche des diviseurs essentiels des singularités algébriques." Grenoble 1, 1993. http://www.theses.fr/1993GRE10027.
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Pour une variete algebrique v, on cherche ici a caracteriser ceux parmi les diviseurs exceptionnels d'une desingularisation de v qui apparaissent aussi sur toutes les autres. Ils sont dits essentiels relativement a v. On se pose egalement le probleme de l'existence d'une desingularisation essentielle de v, dont les diviseurs exceptionnels sont les diviseurs exceptionnels sont tous essentiels. Une variete v torique et affine est associee a un semi-groupe dans un reseau; on en etudie le systeme generateur minimal g. On montre que les diviseurs essentiels pour les desingularisations equivariantes de v sont les orbites de codimension 1 du tore determinees par les elements de g. Si v est de dimension 3, on construit une desingularisation essentielle equivariante, ou g desingularisation, a partir d'un modele terminal minimal quelconque de v. En fait, une g-desingularisation se factorise toujours par un modele terminal minimal et elle est unique lorsque v est elle-meme terminale et q-factorielle. Les demonstrations portent sur la combinatoire des eventails. Dans le cas ou le corps de base est c, on utilise des resultats dus a mori pour etablir que les diviseurs essentiels equivariants restent essentiels pour les desingularisations non equivariantes. On donne aussi les exemples d'une variete torique de dimension 4, puis d'une variete de dimension 3 terminale d'indice 1, qui ne possedent pas de desingularisation essentielle
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Carneiro, Filho João. "Comparação dos níveis de privações entre agricultores familiares no semiárido norte-mineiro frente aos programas de convivência e do microcrédito produtivo rural." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/96703.
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O estudo tenta investigar quais são as fontes de privações que impedem a expansão das liberdades dos agricultores familiares no semiárido norte-mineiro e se a presença do Microcrédito Produtivo Rural (o Agroamigo) e dos Programas de Formação e Mobilização para a Convivência com o Semiárido: Um Milhão de Cisternas Rurais (P1MC/P1 +2) apresenta alguma eficácia com vistas à redução dos níveis de privações destes agricultores. A hipótese central que guia o itinerário deste trabalho tenta confirmar que as políticas e programas voltados para a região do semiárido norte-mineiro, mesmo que articulados, ainda são insuficientes para causar grandes efeitos na agricultura familiar. O que se observa também é a falta, por parte dos agricultores, de uma formação contextualizada para conviver com o semiárido por meio da adoção de tecnologias apropriadas e de estratégias para o enfrentamento à seca. O estudo demandou como aportes teóricos o pensamento crítico do semiárido e a abordagem das capacitações com a finalidade de explicar a realidade da base empírica. Para tanto, foram coletadas 92 amostras em seis comunidades rurais no município de Januária/MG, cujos dados foram operacionalizados e, posteriormente, analisados com base na abordagem das capacitações. A construção do Índice de Liberdade do Agricultor Familiar no Semiárido Norte-Mineiro (ILAF-SAM) deu suporte para mensurar os níveis de privações identificadas nos grupos de funcionamentos de cada liberdade instrumental. Os resultados revelaram ILAF-SAM muito baixo (0,387) na liberdade “A formação contextualizada e a convivência com o semiárido norte-mineiro”, enquadrando-se no nível extremamente alto de privação de liberdade para os agricultores conviverem com o fenômeno da seca. As oportunidades sociais (ILAF-SAM = 0,599), as facilidades econômicas (ILAF-SAM = 0,598), a segurança protetora (ILAF = 0,502) e as garantias de transparência (ILAF-SAM = 0,640), compuseram as principais fontes de privações que cerceiam os agricultores de ampliarem as suas liberdades. Observou-se também fraca articulação entre os programas de convivência e o Microcrédito Produtivo Rural a fim de reduzir as fontes de privações dos agricultores familiares. Mesmo assim, os resultados encontrados em algumas variáveis, isoladamente, foram relevantes no sentido de complementar este estudo e abrir novas perspectivas de pesquisas no semiárido norte-mineiro.The study attempts to investigate what are the sources of deprivations that prevent the expansion of the freedoms of family farmers in the semiarid of northern Minas Gerais and whether the presence of the Rural Productive Microcredit (Agroamigo) and of the Training and Mobilization Programs for Coexistence with Semiarid Conditions: One Million Rural Cisterns (P1MC/P1 +2) has some efficacy in reducing the levels of deprivation of these farmers. The central hypothesis guiding the itinerary of this paper tries to confirm that policies and programs for the semiarid region of the northern Minas Gerais, even when conjoined, are insufficient to cause major positive effects on family farming. What is also observed is the lack, on the part of the farmers, of a contextualized training for living in the semiarid through the adoption of appropriate technologies and strategies for coping with drought. The study demanded as theoretical supports the critical thinking of the semiarid and the capabilities approach in order to explain the reality of the empirical basis. Therefore, 92 samples were collected in six rural communities in the municipality of Januária / MG, whose data were operationalized and subsequently analyzed using the capabilities approach. The construction of the Index of Freedom of the Family Farmer in the semiarid northern Minas Gerais (ILAFSAM) supported measuring the levels of deprivation identified in the groups of each instrumental freedom. The results revealed a very low (0.387) ILAF-SAM for the freedom "Contextualized training and coexistence with the semiarid northern Minas Gerais", characterizing an extremely high level of deprivation of freedom for farmers to live with the phenomenon of drought. Social opportunities (ILAF-SAM = 0.599), the economic possibilities (ILAF-SAM = 0.598), protective security (ILAF = 0.502) and guarantees of transparency (ILAF-SAM = 0.640), along with the previous one, composed the main sources of deprivation that curtail farmers from extending their freedoms.We also observed weak connections between these programs for living with the semiarid and the Rural Productive Microcredit with the aim of reducing the sources of deprivations for family farmers.Even so, the results in some isolated variables were relevant in order to complement this study and open new perspectives for research in the semiarid northern Minas Gerais.
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Sérot, Olivier. "Approche dépendante du temps des phénomènes de tunneling : applications aux potentiels à plusieurs minima, à la désintégration alpha et à la fission nucléaire." Bordeaux 1, 1992. http://www.theses.fr/1992BOR10618.
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Woerner, Sandra Maria [Verfasser], Monika [Akademischer Betreuer] Engelhardt, and Robert [Akademischer Betreuer] Zeiser. "Establishment of a 6-, 8- and 10-color multiparameter flow cytometry assay for the detection of minimal residual disease in multiple myeloma patients: challenging diversity in a straightforward approach." Freiburg : Universität, 2019. http://d-nb.info/1233196715/34.
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Wilke, Daniel Nicolas. "Approaches to accommodate remeshing in shape optimization." Thesis, University of Pretoria, 2010. http://hdl.handle.net/2263/24270.
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This study proposes novel optimization methodologies for the optimization of problems that reveal non-physical step discontinuities. More specifically, it is proposed to use gradient-only techniques that do not use any zeroth order information at all for step discontinuous problems. A step discontinuous problem of note is the shape optimization problem in the presence of remeshing strategies, since changes in mesh topologies may - and normally do - introduce non-physical step discontinuities. These discontinuities may in turn manifest themselves as non-physical local minima in which optimization algorithms may become trapped. Conventional optimization approaches for step discontinuous problems include evolutionary strategies, and design of experiment (DoE) techniques. These conventional approaches typically rely on the exclusive use of zeroth order information to overcome the discontinuities, but are characterized by two important shortcomings: Firstly, the computational demands of zero order methods may be very high, since many function values are in general required. Secondly, the use of zero order information only does not necessarily guarantee that the algorithms will not terminate in highly unfit local minima. In contrast, the methodologies proposed herein use only first order information, rather than only zeroth order information. The motivation for this approach is that associated gradient information in the presence of remeshing remains accurately and uniquely computable, notwithstanding the presence of discontinuities. From a computational effort point of view, a gradient-only approach is of course comparable to conventional gradient based techniques. In addition, the step discontinuities do not manifest themselves as local minima.Thesis (PhD)--University of Pretoria, 2011.
Mechanical and Aeronautical Engineering
unrestricted
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Kaaouachi, Mohamed Hamza. "Une approche distribuée pour les problèmes de couverture dans les systèmes hautement dynamiques." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066058/document.
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Un système distribué est un système composé d'éléments de calcul autonomes dotés de capacité de communication. Il s'agit d'un modèle commun pour l'étude des réseaux. L'évolution rapide des réseaux sans fils et/ou mobiles aussi bien dans la vie quotidienne que dans la recherche amène progressivement à intégrer la dynamique (i.e. l'évolution dans le temps de la connectivité) dans les systèmes distribués. Concrètement, cela revient à ajouter l'hypothèse que les capacités de communication des éléments du système peuvent varier dans le temps. De nombreux modèles considèrent ainsi la dynamique comme composante à part entière du système (et non pas comme une faute). De manière récente, une nouvelle approche, appelée graphe variant dans le temps, tente d'unifier tous ces modèles dans un formalisme commun qui permet de classifier les systèmes en fonction de leurs propriétés de connexité temporelle. Dans cette thèse, nous nous intéressons à des systèmes distribués hautement dynamiques dans lesquels les hypothèses de connexité sont minimalistes. Plus précisément, nous concentrons nos efforts sur les systèmes connexes à travers le temps dans lesquels la seule garantie est que tout élément du système peut infiniment souvent envoyer un message à tout autre (sans garantie sur la pérennité de la route utilisée ni sur le délai de communication). Nous nous intéressons plus particulièrement aux problèmes de couverture (par exemple, ensemble dominant minimal, couplage maximal, ensemble indépendant maximal, ...) dans ces systèmes distribués hautement dynamiques. Les contributions de cette thèse dans ce contexte sont les suivantes. Nous proposons tout d'abord une nouvelle définition pour les problèmes de couverture qui est plus adaptée aux systèmes distribués hautement dynamiques que les définitions existantes. Dans un deuxième temps, nous fournissons un outil générique qui permet de faciliter les preuves de résultats d'impossibilité dans les systèmes distribués dynamiques. Nous appliquons cet outil pour prouver plusieurs résultats d'impossibilité à propos de problèmes de couverture. Ensuite, nous proposons une nouvelle mesure de complexité en temps qui permet de comparer équitablement les performances de protocoles dans les systèmes distribués dynamiques. Enfin, nous donnons un algorithme de construction d'un ensemble dominant minimal dans les systèmes distribués hautement dynamiquesA distributed system is a system of autonomous computing components endowed with communication abilities. This is a common model for the study of networks. The quick evolution of wireless and mobile network both in everyday life and in research gradually leads to take in account the dynamics (i.e. the evolution over time) in distributed systems. Concretely, this means to add the assumption that the communication abilities of the components of the system may vary over time. Many models consider the dynamics as an integral component of the system (and not as a fault). Recently, a new approach, called time-varying graph, attempts to unify all these models in a common formalism which allows the classification systems based on their temporal connectivity properties. In this thesis, we are interested in highly dynamic distributed systems with minimal connectivity assumptions. Specifically, we focus on connected over time systems where the only guarantee is that any element of the system can infinitely often send a message to any other (no guarantee are provided on the sustainability of the used path nor on the time communication). We are particularly interested in covering problems (e.g., minimal dominanting set, maximal matching, maximal independent set, ...) in these highly dynamic distributed systems. The contributions of this thesis in this context are as follows. We first propose a new definition for the covering problems which is more suited to highly dynamic distributed systems that the existing definitions. Secondly, we provide a generic tool to simplify proof of impossibility results in dynamic distributed systems. We use this tool to prove some impossibility results of covering problems. Then, we propose a new time complexity measure to fairly compare the algorithms performance in dynamic distributed systems. Finally, we give an algorithm that compute a minimal dominating set in highly dynamic distributed systems
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Chichignoud, Michael. "Perforamances statistiques d'estimateurs non-linéaires." Phd thesis, Université de Provence - Aix-Marseille I, 2010. http://tel.archives-ouvertes.fr/tel-00540963.
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On se place dans le cadre de l'estimation non paramétrique dans le modèle de régression. Dans un premier temps, on dispose des observations Y dont la densité $g$ est connue et dépend d'une fonction de régression $f(X)$ inconnue. Dans cette thèse, cette fonction est supposée régulière, i.e. appartenant à une boule de Hölder. Le but est d'estimer la fonction $f$ à un point $y$ (estimation ponctuelle). Pour cela, nous développons un estimateur local de type {\it bayésien}, construit à partir de la densité $g$ des observations. Nous proposons une procédure adaptative s'appuyant sur la méthode de Lepski, qui permet de construire un estimateur adaptatif choisi dans la famille des estimateurs bayésiens locales indexés par la fenêtre. Sous certaines hypothèses suffisantes sur la densité $g$, notre estimateur atteint la vitesse adaptative optimale (en un certain sens). En outre, nous constatons que dans certains modèles, l'estimateur bayésien est plus performant que les estimateurs linéaires. Ensuite, une autre approche est considérée. Nous nous plaçons dans le modèle de régression additive, où la densité du bruit est inconnue, mais supposée symétrique. Dans ce cadre, nous développons un estimateur dit de {\it Huber} reposant sur l'idée de la médiane. Cet estimateur permet d'estimer la fonction de régression, quelque soit la densité du bruit additif (par exemple, densité gaussienne ou densité de Cauchy). Avec la méthode de Lepski, nous sélectionnons un estimateur qui atteint la vitesse adaptative classique des estimateurs linéaires sur les espaces de Hölder.
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Comminges, Laëtitia, and Laëtitia Comminges. "Quelques contributions à la sélection de variables et aux tests non-paramétriques." Phd thesis, Université Paris-Est, 2012. http://pastel.archives-ouvertes.fr/pastel-00804979.
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Les données du monde réel sont souvent de très grande dimension, faisant intervenir un grand nombre de variables non pertinentes ou redondantes. La sélection de variables est donc utile dans ce cadre. D'abord, on considère la sélection de variables dans le modèle de régression quand le nombre de variables est très grand. En particulier on traite le cas où le nombre de variables pertinentes est bien plus petit que la dimension ambiante. Sans supposer aucune forme paramétrique pour la fonction de régression, on obtient des conditions minimales permettant de retrouver l'ensemble des variables pertinentes. Ces conditions relient la dimension intrinsèque à la dimension ambiante et la taille de l'échantillon. Ensuite, on considère le problème du test d'une hypothèse nulle composite sous un modèle de régression non paramétrique multi varié. Pour une fonctionnelle quadratique donnée $Q$, l'hypothèse nulle correspond au fait que la fonction $f$ satisfait la contrainte $Q[f] = 0$, tandis que l'alternative correspond aux fonctions pour lesquelles $ |Q[f]|$ est minorée par une constante strictement positive. On fournit des taux minimax de test et les constantes de séparation exactes ainsi qu'une procédure optimale exacte, pour des fonctionnelles quadratiques diagonales et positives. On peut utiliser ces résultats pour tester la pertinence d'une ou plusieurs variables explicatives. L'étude des taux minimax pour les fonctionnelles quadratiques diagonales qui ne sont ni positives ni négatives, fait apparaître deux régimes différents : un régime " régulier " et un régime " irrégulier ". On applique ceci au test de l'égalité des normes de deux fonctions observées dans des environnements bruités
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Lake, Jennifer. "Vers une nouvelle approche pour établir les besoins nutritionnels minimaux (en particulier ceux en P) de la truite arc-en-ciel (Oncorhynchus mykiss) à l'aide de puces génétiques." Thesis, Université Laval, 2007. http://www.theses.ulaval.ca/2007/24521/24521.pdf.
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