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Letteratura scientifica selezionata sul tema "Analyse non convexe"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 2 febbraio 2022

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Articoli di riviste sul tema "Analyse non convexe"

Deguire, Paul, e Andrzej Granas. "Sur une certaine alternative non-linéaire en analyse convexe". Studia Mathematica 83, n. 2 (1986): 127–38. http://dx.doi.org/10.4064/sm-83-2-127-138.

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Volle, M. "Sur quelques formules de dualit� convexe et non convexe". Set-Valued Analysis 2, n. 1-2 (1994): 369–79. http://dx.doi.org/10.1007/bf01027112.

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Neilan, Michael, Abner J. Salgado e Wujun Zhang. "Numerical analysis of strongly nonlinear PDEs". Acta Numerica 26 (1 maggio 2017): 137–303. http://dx.doi.org/10.1017/s0962492917000071.

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We review the construction and analysis of numerical methods for strongly nonlinear PDEs, with an emphasis on convex and non-convex fully nonlinear equations and the convergence to viscosity solutions. We begin by describing a fundamental result in this area which states that stable, consistent and monotone schemes converge as the discretization parameter tends to zero. We review methodologies to construct finite difference, finite element and semi-Lagrangian schemes that satisfy these criteria, and, in addition, discuss some rather novel tools that have paved the way to derive rates of convergence within this framework.

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Grasmair, Markus. "Non-convex sparse regularisation". Journal of Mathematical Analysis and Applications 365, n. 1 (maggio 2010): 19–28. http://dx.doi.org/10.1016/j.jmaa.2009.09.055.

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Kolář, Jan. "Non-compact lamination convex hulls". Annales de l'Institut Henri Poincare (C) Non Linear Analysis 20, n. 3 (maggio 2003): 391–403. http://dx.doi.org/10.1016/s0294-1449(02)00007-0.

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Abuelela, Waleed. "Hardy inequalities for some non-convex domains". Journal of Mathematical Inequalities, n. 1 (2012): 1–14. http://dx.doi.org/10.7153/jmi-06-01.

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Bachir, Mohammed. "A Non-Convex Analogue to Fenchel Duality". Journal of Functional Analysis 181, n. 2 (aprile 2001): 300–312. http://dx.doi.org/10.1006/jfan.2000.3701.

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Brezis, Haïm, e Hoai-Minh Nguyen. "Non-local, non-convex functionals converging to Sobolev norms". Nonlinear Analysis 191 (febbraio 2020): 111626. http://dx.doi.org/10.1016/j.na.2019.111626.

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Chemetov, N., e M. D. P. Monteiro Marques. "Non-convex Quasi-variational Differential Inclusions". Set-Valued Analysis 15, n. 3 (27 aprile 2007): 209–21. http://dx.doi.org/10.1007/s11228-007-0045-9.

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Shih, Mau-Hsiang, e Kok-Keong Tan. "Non-compact sets with convex sections, II". Journal of Mathematical Analysis and Applications 120, n. 1 (novembre 1986): 264–70. http://dx.doi.org/10.1016/0022-247x(86)90214-3.

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Più fonti

Tesi sul tema "Analyse non convexe"

Guillaume, Sophie. "Problèmes d'optimisation et d'évolution en analyse non convexe de type convexe composite". Montpellier 2, 1996. http://www.theses.fr/1996MON20224.

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Cette these est consacree a l'etude de fonctions non necessairement convexes ni regulieres, a savoir les fonctions s'ecrivant comme la composition d'une fonction convexe semicontinue inferieurement avec une application lisse. Sous une condition de qualification, une telle ecriture permet d'utiliser les resultats connus de l'analyse convexe, et de modeliser de nombreux exemples: programmation mathematique non lineaire, problemes avec obstacle, polyconvexite en calcul des variations, problemes de valeurs propres. On etudie, pour ces fonctions dites convexes composites qualifiees, leurs principales proprietes et leurs liens avec d'autres classes de fonctions non convexes, ainsi que divers problemes d'evolution et d'optimisation

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DANIILIDIS, Aris. "Analyse convexe et quasi-convexe ; applications en optimisation". Habilitation à diriger des recherches, Université de Pau et des Pays de l'Adour, 2002. http://tel.archives-ouvertes.fr/tel-00001355.

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Ce document de synthèse s'articule autour de l'analyse convexe, de l'analyse quasi-convexe et des applications en optimisation. Dans le premier domaine on aborde les thèmes de la continuité, de la différentiabilité et des critères de coïncidence pour les fonctions convexes, puis la convexification des fonctions semi-continues inférieurement. Pour l'étude des fonctions quasi-convexes deux approches sont adoptées : une approche analytique, via un sous-différentiel généralisé, et une approche géométrique, basée sur les normales aux tranches. La dernière partie est consacrée à des applications à l'intégration d'opérateurs multivoques, aux inéquations variationnelles et à des problèmes d'optimisation multicritères en dimension finie et infinie. Parmi les nouveautés de ce travail, on trouve la notion de monotonie fortement cyclique, qui caractérise le sous-différentiel d'une fonction convexe dont la restriction à son domaine est continue, la quasi-monotonie cyclique, qui est une propriété intrinsèque du sous-différentiel d'une fonction quasi-convexe avec des applications importantes en économie mathématique, et la notion de quasi-monotonie propre, qui caractérise les opérateurs pour lesquels l'inéquation variationnelle associée a toujours des solutions sur toute sous-partie convexe et faiblement compacte de leur domaine. Notons encore une nouvelle caractérisation de la propriété de Radon-Nikodym, et une extension à la dimension infinie d'un résultat de Janin concernant l'intégration d'un opérateur maximal cycliquement sous-monotone, résultat qui généralise le théorème classique de Rockafellar pour les opérateurs maximaux cycliquement monotones.

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Cadoux, Florent. "Optimisation et analyse convexe pour la dynamique non-régulière". Phd thesis, Université Joseph Fourier (Grenoble), 2009. http://tel.archives-ouvertes.fr/tel-00440798.

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L'objectif de ce travail est de proposer une nouvelle approche pour la résolution du problème de contact unilatéral avec frottement de Coulomb tridimensionnel en mécanique des solides. On s'intéresse à des systèmes dynamiques composés de plusieurs corps possédant un nombre fini de degrés de liberté: rigides, ou déformables qui sont des approximations spatiales de modèles continus. Le frottement entre les corps est modélisé en utilisant une formulation classique de la loi de Coulomb. Après discrétisation en temps (ou approximation quasi-statique), on obtient à chaque pas de temps un problème contenant des équations de complémentarité sur un produit de cônes du second ordre, et d'autres équations. Plusieurs méthodes de résolution ont été proposées pour différentes formulations équivalentes de ce problème, en particulier par Moreau, Alart et Curnier, et De Saxcé. En considérant les équations de complémentarité comme celles des conditions d'optimalité (KKT) d'un problème d'optimisation, on propose une reformulation équivalente nouvelle sous forme d'un problème de minimisation paramétrique convexe couplé avec un problème de point fixe. Grâce à ce point de vue, on démontre l'existence de solutions sous une hypothèse assez faible, et vérifiable en pratique. De plus, on peut souvent calculer effectivement l'une de ces solutions en résolvant numériquement l'équation de point fixe. Les performances de cette approche sont comparées à celles des méthodes existantes.

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Bachir, Mohammed. "Dualité, calcul sous différentiel et intégration en analyse non lisse et non convexe". Bordeaux 1, 2000. http://www.theses.fr/2000BOR10515.

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Cette these est consacree a l'etude de trois sujets de l'analyse non lisse. Dans le premier chapitre, nous introduisons et etudions une nouvelle version de la dualite de fenchel dans un cadre non convexe. Une version du resultat classique de smulian est etablie dans le cadre de cette dualite. Comme application nous deduisons la frechet differentiabilite generique de la norme. Dans certains espaces de fonctions continues bornees (ex. Lip (x), 0 < 1). D'autre part, nous etendons le theoreme de banach-stone aux espaces metriques complets et a une classe abstraite de fonctions continues bornees a valeurs vectorielles. Dans le second chapitre, nous etudions une condition de qualification stable par perturbation par des fonctions uniformements continues. Ceci permet de formuler un resultat qui entraine le calcul sous-differentiel. D'autre part, nous donnons une inegalite des accroissements finis multidirectionnelle avec une information au second ordre. Nous appliquons ce resultat a l'unicite des solutions de viscosite des equations de hamilton-jacobi du second ordre en dimension finie. Le dernier chapitre concerne l'integration de certaines classes d'operateurs multivoques satisfaisant une propriete similaire a la cyclique monotonicite. Nous considerons le cas des fonctions quasi-convexes et le sous-differentiel inferieur.

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Li, Wei. "Analyse numérique de problèmes non convexes à donnée au bord non linéaire". Metz, 1993. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/1993/Li.Wei.SMZ9310.pdf.

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Ce travail porte sur l'étude des problèmes non convexes. Ils interviennent dans le domaine des matériaux, par exemple cristaux, etc. Nous considérons les problèmes suivants : inf#(*(x)) dx; inf#(*(x))+((x)a(x)) dx sur certains espaces de Sobolev w#1#p(a) et ou la densité d'énergie possède des puits de potentiels. En général, de tels problèmes n'admettent pas de solution classique. Sur cette étude, une approche, introduite par M. Chipot, C. Collins et D. Kinderlerer, a été développée. Dans les sections 1 et 2, des résultats d'estimations dans l'espace des éléments-finis ont été obtenus. La section 3 est consacrée à une analyse paramétrée. On obtient un résultat de la mesure de Young qui décrit l'existence et l'unicité de la solution généralisée. Enfin dans la section 4, des estimations au point de vue probabiliste ont été déduits, et expliquent le comportement des suites minimisantes
In this thesis, we study a kind of non-convex varaitional problems. Such problems originated in material science, for example in crystal, etc. We consider the following problems : inf#(*(x)) dx; inf#(*(x))+((x)a(x)) dx on certain Sobolev space w#1#p(a) and where the energy density posses energy wells, say w1 i=1,. . . K. In general, such problems can be no classical solution. In our studies, the numerical method introduced by M. Chipot, C. Collins and D. Kinderlerer has been developped. In section 1 and 2 some results of estimation in a space of finit-element are obtained. Section 3 is contributed to an analysis or parametrized measure. We get a result of Young measure which showing the existence and uniqueness of the generalized solution. And in section 4, we have some estimation results in terms of probability, which explains the behavior of the minimising sequences

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Zaourar, Sofia. "Optimisation convexe non-différentiable et méthodes de décomposition en recherche opérationnelle". Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENM099.

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Les méthodes de décomposition sont une application du concept de diviser pour régner en optimisation. L'idée est de décomposer un problème d'optimisation donné en une séquence de sous-problèmes plus faciles à résoudre. Bien que ces méthodes soient les meilleures pour un grand nombre de problèmes de recherche opérationnelle, leur application à des problèmes réels de grande taille présente encore de nombreux défis. Cette thèse propose des améliorations méthodologiques et algorithmiques de méthodes de décomposition. Notre approche est basée sur l'analyse convexe et l'optimisation non-différentiable. Dans la décomposition par les contraintes (ou relaxation lagrangienne) du problème de planification de production électrique, même les sous-problèmes sont trop difficiles pour être résolus exactement. Mais des solutions approchées résultent en des prix instables et chahutés. Nous présentons un moyen simple d'améliorer la structure des prix en pénalisant leurs oscillations, en utilisant en particulier une régularisation par variation totale. La consistance de notre approche est illustrée sur des problèmes d'EDF. Nous considérons ensuite la décomposition par les variables (ou de Benders) qui peut avoir une convergence excessivement lente. Avec un point de vue d'optimisation non-différentiable, nous nous concentrons sur l'instabilité de l'algorithme de plans sécants sous-jacent à la méthode. Nous proposons une stabilisation quadratique de l'algorithme de Benders, inspirée par les méthodes de faisceaux en optimisation convexe. L'accélération résultant de cette stabilisation est illustrée sur des problèmes de conception de réseau et de localisation de plates-formes de correspondance (hubs). Nous nous intéressons aussi plus généralement aux problèmes d'optimisation convexe non-différentiable dont l'objectif est coûteux à évaluer. C'est en particulier une situation courante dans les procédures de décomposition. Nous montrons qu'il existe souvent des informations supplémentaires sur le problème, faciles à obtenir mais avec une précision inconnue, qui ne sont pas utilisées dans les algorithmes. Nous proposons un moyen d'incorporer ces informations incontrôlées dans des méthodes classiques d'optimisation convexe non-différentiable. Cette approche est appliquée avec succès à desproblèmes d'optimisation stochastique. Finalement, nous introduisons une stratégie de décomposition pour un problème de réaffectation de machines. Cette décomposition mène à une nouvelle variante de problèmes de conditionnement vectoriel (vectorbin packing) où les boîtes sont de taille variable. Nous proposons des heuristiques efficaces pour ce problème, qui améliorent les résultats de l'état de l'art du conditionnement vectoriel. Une adaptation de ces heuristiques permet de construire des solutions réalisables au problème de réaffectation de machines de Google
Decomposition methods are an application of the divide and conquer principle to large-scale optimization. Their idea is to decompose a given optimization problem into a sequence of easier subproblems. Although successful for many applications, these methods still present challenges. In this thesis, we propose methodological and algorithmic improvements of decomposition methods and illustrate them on several operations research problems. Our approach heavily relies on convex analysis and nonsmooth optimization. In constraint decomposition (or Lagrangian relaxation) applied to short-term electricity generation management, even the subproblems are too difficult to solve exactly. When solved approximately though, the obtained prices show an unstable noisy behaviour. We present a simple way to improve the structure of the prices by penalizing their noisy behaviour, in particular using a total variation regularization. We illustrate the consistency of our regularization on real-life problems from EDF. We then consider variable decomposition (or Benders decomposition), that can have a very slow convergence. With a nonsmooth optimization point of view on this method, we address the instability of Benders cutting-planes algorithm. We present an algorithmic stabilization inspired by bundle methods for convex optimization. The acceleration provided by this stabilization is illustrated on network design andhub location problems. We also study more general convex nonsmooth problems whose objective function is expensive to evaluate. This situation typically arises in decomposition methods. We show that it often exists extra information about the problem, cheap but with unknown accuracy, that is not used by the algorithms. We propose a way to incorporate this coarseinformation into classical nonsmooth optimization algorithms and apply it successfully to two-stage stochastic problems.Finally, we introduce a decomposition strategy for the machine reassignment problem. This decomposition leads to a new variant of vector bin packing problems, where the bins have variable sizes. We propose fast and efficient heuristics for this problem that improve on state of the art results of vector bin packing problems. An adaptation of these heuristics is also able to generate feasible solutions for Google instances of the machine reassignment problem

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Le, Ba Khiet. "Stabilité des systèmes dynamiques non-réguliers et applications". Limoges, 2013. http://www.theses.fr/2013LIMO4054.

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L'objectif principal de cette thèse est de proposer une formulation pour l'étude et l'analyse de stabilité des systèmes dynamiques non-réguliers avec une attention particulière aux applications issues des circuits électriques et des systèmes mécaniques avec frottement sec. Les outils mathématiques utilisés sont issus de l'analyse non-lisse et de la théorie de stabilité au sens de Lyapounov. Dans le détail, nous utilisons un formalisme pour modéliser la complémentarité des systèmes de commutation simples et des inclusions différentielles pour modéliser un convertisseur DC-DC de type Buck, les systèmes dynamiques Lagrangian ainsi que les systèmes de Lur'e. Pour chaque modèle, nous nous intéressons à l'existence d'une solution, des propriétés de stabilité des trajectoires, de la stabilité en temps fini ou de mettre une force sur la commande pour obtenir la stabilité en temps fini. Nous proposons aussi quelques méthodes numériques pour simuler ces systèmes. Il est à noter que les méthodes utilisées dans ce manuscrit peuvent être appliquées pour l'analyse de systèmes dynamiques non-réguliers issus d'autres domaines tels que l'économie, la finance ou la biologie. .
This manuscript deals with the stability of non-smooth dynamical systems and applications. More precisely, we aim to provide a formulation to study the stability analysis of non-smooth dynamical systems, particularly in electrical circuits and mechanics with dry friction and robustness. The efficient tools which we have used are non-smooth analysis, Lyapunov stability theorem and non-smooth mathematical frameworks : complementarity and differentials inclusions. In details, we use complementarity formalism to model some simple switch systems and differential inclusions to model a Dc-Dc Buck converter, Lagrange dynamical systems and Lur'e systems. For each model, we are interested in the well-posedness, stability properties of trajectories, even finite-time stability or putting a control force to obtain finite-time stability, and finding numerical ways to simulate the systems. The theoretical results are supported by some examples in electrical circuits and mechanics with numerical simulations. It is noted that the method used in this monograph can be applied to analyze for non-smooth dynamical systems from other fields such as economics, finance or biology. .

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Nacry, Florent. "Processus d’évolution discontinus de Moreau et stabilité de la prox-régularité : Applications à l’optimisation non-convexe et aux équations généralisée". Thesis, Limoges, 2017. http://www.theses.fr/2017LIMO0022.

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Cette thèse est consacrée, d'une part, à l'étude d'existence de solutions pour des problèmes d'évolution et, d'autre part, à la stabilité de la propriété de prox-régularité ensembliste. Nous étudions dans la première partie des processus de rafle de Moreau perturbés et discontinu du premier et du second ordre. L'ensemble mouvant est prox-régulier dans un espace de Hilbert réel quelconque et sa variation est contrôlé par une mesure de Radon. Des applications à la théorie de la complémentarité et à celle des inéquations variationnelles sont présentées. Dans la seconde partie, on donne des conditions suffisantes assurant la prox-régularité d'ensembles décrit par des contraintes non nécessairement lisses sous forme d'inégalités et/ ou d'égalités et plus généralement d'ensembles de solutions d'équations généralisées. On y développe également des conditions vérifiables assurant la préservation de la prox-régularité vis-à-vis d'opérations ensemblistes : les cas de l'intersection, d'image directe, de pré-image, d'union et projection sur un sous-espace sont considérés
In this dissertation, we study, on the one hand, the existence of solutions for some evolution problems and, on the other hand, the stability of prox-regularity under set operations. The first topic is devoted to first and second order nonconvex perturberd Moreau's sweeping processes in infinite dimensional framework. The moving set is assumed to be prox-regular and moved in a bounded variation way. Applications to the theory of complementarity problems and evolution variational inequalities are given. In the other topic, we first give verifiable sufficient conditions ensuring the prox-regularity of constrained sets and more generally for solution sets of generalized equations. We also develop the preservation of prox-regularity under set operations as intersection, direct image, inverse image, union and projection along a vector space

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Ta, Minh Thuy. "Techniques d'optimisation non convexe basée sur la programmation DC et DCA et méthodes évolutives pour la classification non supervisée". Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0099/document.

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Nous nous intéressons particulièrement, dans cette thèse, à quatre problèmes en apprentissage et fouille de données : clustering pour les données évolutives, clustering pour les données massives, clustering avec pondération de variables et enfin le clustering sans connaissance a priori du nombre de clusters avec initialisation optimale des centres de clusters. Les méthodes que nous décrivons se basent sur des approches d’optimisation déterministe, à savoir la programmation DC (Difference of Convex functions) et DCA (Difference of Convex Algorithms), pour la résolution de problèmes de clustering cités précédemment, ainsi que des approches évolutionnaires élitistes. Nous adaptons l’algorithme de clustering DCA–MSSC pour le traitement de données évolutives par fenêtres, en appréhendant les données évolutives avec deux modèles : fenêtres fixes et fenêtres glissantes. Pour le problème du clustering de données massives, nous utilisons l’algorithme DCA en deux phases. Dans la première phase, les données massives sont divisées en plusieurs sous-ensembles, sur lesquelles nous appliquons l’algorithme DCA–MSSC pour effectuer un clustering. Dans la deuxième phase, nous proposons un algorithme DCA-Weight pour effectuer un clustering pondéré sur l’ensemble des centres obtenues à la première phase. Concernant le clustering avec pondération de variables, nous proposons également deux approches: clustering dur avec pondération de variables et clustering floue avec pondération de variables. Nous testons notre approche sur un problème de segmentation d’image. Le dernier problème abordé dans cette thèse est le clustering sans connaissance a priori du nombre des clusters. Nous proposons pour cela une approche évolutionnaire élitiste. Le principe consiste à utiliser plusieurs algorithmes évolutionnaires (EAs) en même temps, de les faire concourir afin d’obtenir la meilleure combinaison de centres initiaux pour le clustering et par la même occasion le nombre optimal de clusters. Les différents tests réalisés sur plusieurs ensembles de données de grande taille sont très prometteurs et montrent l’efficacité des approches proposées
This thesis focus on four problems in data mining and machine learning: clustering data streams, clustering massive data sets, weighted hard and fuzzy clustering and finally the clustering without a prior knowledge of the clusters number. Our methods are based on deterministic optimization approaches, namely the DC (Difference of Convex functions) programming and DCA (Difference of Convex Algorithm) for solving some classes of clustering problems cited before. Our methods are also, based on elitist evolutionary approaches. We adapt the clustering algorithm DCA–MSSC to deal with data streams using two windows models: sub–windows and sliding windows. For the problem of clustering massive data sets, we propose to use the DCA algorithm with two phases. In the first phase, massive data is divided into several subsets, on which the algorithm DCA–MSSC performs clustering. In the second phase, we propose a DCA–Weight algorithm to perform a weighted clustering on the obtained centers in the first phase. For the weighted clustering, we also propose two approaches: weighted hard clustering and weighted fuzzy clustering. We test our approach on image segmentation application. The final issue addressed in this thesis is the clustering without a prior knowledge of the clusters number. We propose an elitist evolutionary approach, where we apply several evolutionary algorithms (EAs) at the same time, to find the optimal combination of initial clusters seed and in the same time the optimal clusters number. The various tests performed on several sets of large data are very promising and demonstrate the effectiveness of the proposed approaches

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Alaa, Nour Eddine. "Étude d'équations elliptiques non linéaires à dépendance convexe en le gradient et à données mesures". Nancy 1, 1989. http://www.theses.fr/1989NAN10460.

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Dans ce travail, l'étude porte sur les équations elliptiques non linéaires de la forme où j(x,. ) est convexe, continue positive, f une donnée mesure positive sur. . . Et un paramètre réel. Si j(x,. ) est sur-linéaire à l'infini, une condition nécessaire d'existence de solution est que f doit être assez régulière et assez petit. Nous commençons par une étude complète du problème en dimension un et nous obtenons une caractérisation de cette régularité et de cette taille en termes d'un problème dual de minimisation associé

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Più fonti

Libri sul tema "Analyse non convexe"

Hendricus, Schikhof Wilhelmus, a cura di. Locally convex spaces over non-Archimedean valued fields. Cambridge, UK: Cambridge University Press, 2010.

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Perez-Garcia, C. Locally convex spaces over non-Archimedean valued fields. New York: Cambridge University Press, 2009.

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Foundations of complex analysis in non locally convex spaces: Function theory without convexity condition. Amsterdam: Elsevier, 2003.

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Liana, Lupșa, a cura di. Non-connected convexities and applications. Dordrecht: Kluwer Academic Publishers, 2002.

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Lombardo, Luca. Albertino Mussato, Epistole metriche Edizione critica, traduzione e commento. Venice: Fondazione Università Ca’ Foscari, 2020. http://dx.doi.org/10.30687/978-88-6969-436-3.

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The Metric Epistles of Albertino Mussato (1261-1329) are a collection of 20 compositions in Latin verse (of which, 12 in elegiac couplets, 8 in hexameters, for a total of 1,570 verses) composed between 1309 and 1326 and addressed to different recipients. The list of recipients includes friends of the author and representatives of the Paduan political and intellectual élite of the early 14th century such as the judges Rolando da Piazzola, Giovanni da Vigonza and Paolo da Teolo, the notary Zambono d’Andrea and Marsilio Mainardini; masters of grammar and rhetoric such as the Venetian Giovanni Cassio, Bonincontro from Mantua and Guizzardo from Bologna; religious personalities such as the Dominican friars Benedetto and Giovannino da Mantova, respectively lecturer and professor of theology at the Studium Generale of the convent of S. Agostino in Padua; collective recipients, such as the College of Artists and fellow citizens of Padua. After an editio princeps was printed in Venice in 1636 on the basis of a now lost manuscript, a critical edition of the Epistles is published here for the first time, including the complete corpus of the texts in the light of their entire manuscript tradition. The texts are accompanied by an Italian translation and a detailed commentary, which mainly aims to bring to light and analyse the dense intertextuality of Mussato’s poem (in particular classical Latin sources), reconsidering the cultural background of the author and his contemporaries in the context of the so-called ‘Paduan prehumanism’ and an ideal dialogue with Dante’s coeval biographical and literary experiences.

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Chambers, Robert G. Competitive Agents in Certain and Uncertain Markets. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190063016.001.0001.

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This book uses concepts from optimization theory to develop an integrated analytic framework for treating consumer, producer, and market equilibrium analyses as special cases of a generic optimization problem. The same framework applies to both stochastic and non-stochastic decision settings, so that the latter is recognized as an (important) special case of the former. The analytic techniques are borrowed from convex analysis and variational analysis. Special emphasis is given to generalized notions of differentiability, conjugacy theory, and Fenchel's Duality Theorem. The book shows how virtually identical conjugate analyses form the basis for modeling economic behavior in each of the areas studied. The basic analytic concepts are borrowed from convex analysis. Special emphasis is given to generalized notions of differentiability, conjugacy theory, and Fenchel's Duality Theorem. It is demonstrated how virtually identical conjugate analyses form the basis for modelling economic behaviour in each of the areas studied.

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Cristescu, G., e L. Lupsa. Non-Connected Convexities and Applications. Springer, 2014.

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Cristescu, G., e L. Lupsa. Non-Connected Convexities and Applications (Applied Optimization). Springer, 2002.

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Epstein, Charles L., e Rafe Mazzeo. Wright-Fisher Geometry. Princeton University Press, 2017. http://dx.doi.org/10.23943/princeton/9780691157122.003.0002.

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This chapter introduces the geometric preliminaries needed to analyze generalized Kimura diffusions, with particular emphasis on Wright–Fisher geometry. It begins with a discussion of the natural domains of definition for generalized Kimura diffusions: polyhedra in Euclidean space or, more generally, abstract manifolds with corners. Amongst the convex polyhedra, the chapter distinguishes the subclass of regular convex polyhedra P. P is a regular convex polyhedron if it is convex and if near any corner, P is the intersection of no more than N half-spaces with corresponding normal vectors that are linearly independent. These definitions establish that any regular convex polyhedron is a manifold with corners. The chapter concludes by defining the general class of elliptic Kimura operators on a manifold with corners P and shows that there is a local normal form for any operator L in this class.

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Mathews, Debra J. H. When emerging biomedical technologies converge or collide. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198786832.003.0001.

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Neuroethics is concerned with the ethical, legal, and policy issues raised by the neurosciences and their applications in medicine and society. However, neuroscience sometimes involves other emerging biomedical technologies, such as genetics, regenerative medicine, and synthetic biology, which generate their own ethics and policy conundrums. When emerging biomedical technologies converge or collide in a single project, application, or product, challenges are compounded. These challenges may be mitigated by the development of shared models for ethical analysis focused not on the details of a particular technology but rather on the nature of the class of technologies, such as whether they are emerging, rapidly evolving, and ethically contentious. These challenges and characteristics, and a framework approach to managing them, are the focus of this chapter.

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Capitoli di libri sul tema "Analyse non convexe"

Joro, Tarja, e Pekka J. Korhonen. "Non-convex Value Efficiency Analysis". In International Series in Operations Research & Management Science, 147–59. Boston, MA: Springer US, 2014. http://dx.doi.org/10.1007/978-1-4899-7528-7_10.

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Rémon, M. "Convex Discriminant Analysis Tools for Non Convex Pattern Recognition". In Studies in Classification, Data Analysis, and Knowledge Organization, 159–66. Berlin, Heidelberg: Springer Berlin Heidelberg, 2002. http://dx.doi.org/10.1007/978-3-642-55991-4_17.

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Amyari, Maryam, e Ghadir Sadeghi. "Isometrics in Non-Archimedean Strictly Convex and Strictly 2-Convex 2-Normed Spaces". In Nonlinear Analysis and Variational Problems, 13–22. New York, NY: Springer New York, 2009. http://dx.doi.org/10.1007/978-1-4419-0158-3_2.

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Bakelman, Ilya J. "Non-Compact Problems for Elliptic Solutions of Monge-Ampere Equations". In Convex Analysis and Nonlinear Geometric Elliptic Equations, 204–26. Berlin, Heidelberg: Springer Berlin Heidelberg, 1994. http://dx.doi.org/10.1007/978-3-642-69881-1_5.

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Große, Andree, Kai Rothaus e Xiaoyi Jiang. "Detection of Non-convex Objects by Dynamic Programming". In Computer Analysis of Images and Patterns, 285–92. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-03767-2_35.

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Bakelman, Ilya J. "The Geometric Maximum Principle for General Non-Divergent Quasilinear Elliptic Equations". In Convex Analysis and Nonlinear Geometric Elliptic Equations, 339–495. Berlin, Heidelberg: Springer Berlin Heidelberg, 1994. http://dx.doi.org/10.1007/978-3-642-69881-1_8.

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Rémon, Marcel. "Discriminant Analysis Tools for Non Convex Pattern Recognition". In Studies in Classification, Data Analysis, and Knowledge Organization, 241–46. Berlin, Heidelberg: Springer Berlin Heidelberg, 2000. http://dx.doi.org/10.1007/978-3-642-59789-3_39.

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Majumdar, Angshul, e Rabab K. Ward. "Under-Determined Non-cartesian MR Reconstruction with Non-convex Sparsity Promoting Analysis Prior". In Medical Image Computing and Computer-Assisted Intervention – MICCAI 2010, 513–20. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-15711-0_64.

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Kitić, Srđan, Nancy Bertin e Rémi Gribonval. "Sparsity and Cosparsity for Audio Declipping: A Flexible Non-convex Approach". In Latent Variable Analysis and Signal Separation, 243–50. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-22482-4_28.

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Tone, Kaoru, e Miki Tsutsui. "HOW TO DEAL WITH NON-CONVEX FRONTIERS IN DATA ENVELOPMENT ANALYSIS". In Advances in DEA Theory and Applications, 271–99. Chichester, UK: John Wiley & Sons, Ltd, 2017. http://dx.doi.org/10.1002/9781118946688.ch20.

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Atti di convegni sul tema "Analyse non convexe"

Xu, Yi, Zhuoning Yuan, Sen Yang, Rong Jin e Tianbao Yang. "On the Convergence of (Stochastic) Gradient Descent with Extrapolation for Non-Convex Minimization". In Twenty-Eighth International Joint Conference on Artificial Intelligence {IJCAI-19}. California: International Joint Conferences on Artificial Intelligence Organization, 2019. http://dx.doi.org/10.24963/ijcai.2019/556.

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Extrapolation is a well-known technique for solving convex optimization and variational inequalities and recently attracts some attention for non-convex optimization. Several recent works have empirically shown its success in some machine learning tasks. However, it has not been analyzed for non-convex minimization and there still remains a gap between the theory and the practice. In this paper, we analyze gradient descent and stochastic gradient descent with extrapolation for finding an approximate first-order stationary point in smooth non-convex optimization problems. Our convergence upper bounds show that the algorithms with extrapolation can be accelerated than without extrapolation.

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Zhang, Hu, Pan Zhou, Yi Yang e Jiashi Feng. "Generalized Majorization-Minimization for Non-Convex Optimization". In Twenty-Eighth International Joint Conference on Artificial Intelligence {IJCAI-19}. California: International Joint Conferences on Artificial Intelligence Organization, 2019. http://dx.doi.org/10.24963/ijcai.2019/591.

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Majorization-Minimization (MM) algorithms optimize an objective function by iteratively minimizing its majorizing surrogate and offer attractively fast convergence rate for convex problems. However, their convergence behaviors for non-convex problems remain unclear. In this paper, we propose a novel MM surrogate function from strictly upper bounding the objective to bounding the objective in expectation. With this generalized surrogate conception, we develop a new optimization algorithm, termed SPI-MM, that leverages the recent proposed SPIDER for more efficient non-convex optimization. We prove that for finite-sum problems, the SPI-MM algorithm converges to an stationary point within deterministic and lower stochastic gradient complexity. To our best knowledge, this work gives the first non-asymptotic convergence analysis for MM-alike algorithms in general non-convex optimization. Extensive empirical studies on non-convex logistic regression and sparse PCA demonstrate the advantageous efficiency of the proposed algorithm and validate our theoretical results.

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ISHIWATA, TETSUYA. "MOTION OF NON-CONVEX POLYGON BY CRYSTALLINE CURVATURE FLOW AND ITS GENERALIZATION". In Proceedings of the International Conference on Nonlinear Analysis. WORLD SCIENTIFIC, 2008. http://dx.doi.org/10.1142/9789812709257_0008.

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Mattsen, Sven, Arne Wichmann e Sibylle Schupp. "A non-convex abstract domain for the value analysis of binaries". In 2015 IEEE 22nd International Conference on Software Analysis, Evolution and Reengineering (SANER). IEEE, 2015. http://dx.doi.org/10.1109/saner.2015.7081837.

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Blanchet, Jose, Christopher Dolan e Henry Lam. "Robust rare-event performance analysis with natural non-convex constraints". In 2014 Winter Simulation Conference - (WSC 2014). IEEE, 2014. http://dx.doi.org/10.1109/wsc.2014.7019924.

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Ding, Hua, Ninggang Shen, Keqin Li, Wu Bo, Chelsey N. Pence e Hongtao Ding. "Experimental and Numerical Analysis of Laser Peen Forming Mechanisms of Sheet Metal". In ASME 2014 International Manufacturing Science and Engineering Conference collocated with the JSME 2014 International Conference on Materials and Processing and the 42nd North American Manufacturing Research Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/msec2014-4210.

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Laser peen forming (LPF) is a novel non-contact sheet metal forming process without detrimental thermal defects. High pressure shock waves induced by a focused laser pulse are applied on the workpiece surface to generate deformations. In this study, the deformation mechanisms induced by LPF are experimentally and numerically investigated under different experimental conditions. Experiments have shown that when keeping laser parameters constant, deformation mechanisms vary depending on the sample thickness. The results show that aluminum sheet samples of 0.25 mm in thickness bend concavely for pulse energy ranging from 0.2 to 0.5 J, while 1.75 mm aluminum sheets bend convexly under the same conditions. There is a transition thickness threshold of sheet metal at which the deformation mechanism changes from concave to convex with the increase of the sample thickness with certain levels of laser parameter. This transition thickness threshold is determined to be around 0.7–0.88mm with the studied process parameters. Experiments also show that as the pulse energy increases, the transition thickness of the bending deformation mechanism increases slightly. Under the concave deformation mechanism, the workpiece is more sensitive to pulse energy, while pulse energy is not a critical factor in the convex mechanism. A finite element analysis (FEA) is performed to simulate the LPF deformation process with different specimen thicknesses and loading conditions. The simulation results agreed well with experimental results.

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López, J., P. Gómez, C. Zanzi, F. Faura e J. Hernández. "Application of Non-Convex Analytic and Geometric Tools to a PLIC-VOF Method". In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-67409.

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An efficient approach to handle either convex or non-convex arbitrary polytopes is applied to volume truncation and volume conservation enforcement operations involved in volume of fluid (VOF) methods. A comparison between the proposed approach and conventional procedures based on convex decomposition is carried out for different tests, demonstrating that the proposed tools represent a substantial improvement in computational efficiency. A speedup of around one order of magnitude is achieved for the reconstruction of several interfacial shapes. The non-convex tools have been used to implement a highly accurate volume of fluid (VOF) method based on a multidimensional advection scheme with edge-matched flux polyhedra and a piecewise linear interface calculation (PLIC) method. A preliminary analysis of the accuracy, computational efficiency and volume conservation properties of the implemented PLIC-VOF method is carried out.

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Rukavishnikov, Viktor A., e Alexey V. Rukavishnikov. "New numerical approach for solving the oseen problem in a convection form in non-convex domain". In INTERNATIONAL CONFERENCE ON ANALYSIS AND APPLIED MATHEMATICS (ICAAM 2020). AIP Publishing, 2021. http://dx.doi.org/10.1063/5.0040324.

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Chan, Tsung-Han, Wing-Kin Ma, Chong-Yung Chi e Yue Wang. "A Convex Analysis Based Criterion for Blind Separation of Non-Negative Sources". In 2007 IEEE International Conference on Acoustics, Speech, and Signal Processing. IEEE, 2007. http://dx.doi.org/10.1109/icassp.2007.366841.

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Althoff, Matthias. "Reachability analysis of nonlinear systems using conservative polynomialization and non-convex sets". In the 16th international conference. New York, New York, USA: ACM Press, 2013. http://dx.doi.org/10.1145/2461328.2461358.

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Rapporti di organizzazioni sul tema "Analyse non convexe"

Hellström, Anders. How anti-immigration views were articulated in Sweden during and after 2015. Malmö University, Malmö Institute for Studies of Migration, Diversity and Welfare (MIM), 2021. http://dx.doi.org/10.24834/isbn.9789178771936.

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The development towards the mainstreaming of extremism in European countries in the areas of immigration and integration has taken place both in policy and in discourse. The harsh policy measures that were implemented after the 2015 refugee crisis have led to a discursive shift; what is normal to say and do in the areas of immigration and integration has changed. Anti-immigration claims are today not merely articulated in the fringes of the political spectrum but more widely accepted and also, at least partly, officially sanctioned. This study investigates the anti-immigration claims, seen as (populist) appeals to the people that centre around a particular mythology of the people and that are, as such, deeply ingrained in national identity construction. The two dimensions of the populist divide are of relevance here: The horizontal dimension refers to articulated differences between "the people", who belong here, and the "non-people" (the other), who do not. The vertical dimension refers to articulated differences between the common people and the established elites. Empirically, the analysis shows how anti-immigration views embedded in processes of national myth making during and after 2015 were articulated in the socially conservative online newspaper Samtiden from 2016 to 2019. The results indicate that far-right populist discourse conveys a nostalgia for a golden age and a cohesive and homogenous collective identity, combining ideals of cultural conformism and socioeconomic fairness.

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Rincón-Torres, Andrey Duván, Kimberly Rojas-Silva e Juan Manuel Julio-Román. The Interdependence of FX and Treasury Bonds Markets: The Case of Colombia. Banco de la República, settembre 2021. http://dx.doi.org/10.32468/be.1171.

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We study the interdependence of FX and Treasury Bonds (TES) markets in Colombia. To do this, we estimate a heteroskedasticity identified VAR model on the returns of the COP/USD exchange rate (TRM) and bond prices, as well as event-analysis models for return volatilities, number of quotes, quote volume, and bid/ask spreads. The data under analysis consists of 5-minute intraday bid/ask US dollar prices and bond quotes, for an assortment of bond species. For these species we also have the number of bid/ask quotes as well as their volume. We found, also, that the exchange rate conveys information to the TES market, but the opposite does not completely hold: A one percent COP depreciation leads to a persistent reduction of TES prices between 0.05% and 0.22%. However, a 1% TES price increase has a very small effect and not entirely significant on the exchange rate, i.e. a COP appreciation between 0.001% and 0.009%. Furthermore, TRM return volatility increases do not affect bond return volatility but its liquidity, i.e. the bid/ask quote number and volume. These results are coherent with the fact that the FX market more efficiently reflects the effect of shocks than the TES market, which may be due to its low liquidity and concentration on a specific habitat. These results have implications for the design of financial stability policies as well as for private portfolio design, rebalancing and hedging.

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Yatsymirska, Mariya. SOCIAL EXPRESSION IN MULTIMEDIA TEXTS. Ivan Franko National University of Lviv, febbraio 2021. http://dx.doi.org/10.30970/vjo.2021.49.11072.

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The article investigates functional techniques of extralinguistic expression in multimedia texts; the effectiveness of figurative expressions as a reaction to modern events in Ukraine and their influence on the formation of public opinion is shown. Publications of journalists, broadcasts of media resonators, experts, public figures, politicians, readers are analyzed. The language of the media plays a key role in shaping the worldview of the young political elite in the first place. The essence of each statement is a focused thought that reacts to events in the world or in one’s own country. The most popular platform for mass information and social interaction is, first of all, network journalism, which is characterized by mobility and unlimited time and space. Authors have complete freedom to express their views in direct language, including their own word formation. Phonetic, lexical, phraseological and stylistic means of speech create expression of the text. A figurative word, a good aphorism or proverb, a paraphrased expression, etc. enhance the effectiveness of a multimedia text. This is especially important for headlines that simultaneously inform and influence the views of millions of readers. Given the wide range of issues raised by the Internet as a medium, research in this area is interdisciplinary. The science of information, combining language and social communication, is at the forefront of global interactions. The Internet is an effective source of knowledge and a forum for free thought. Nonlinear texts (hypertexts) – «branching texts or texts that perform actions on request», multimedia texts change the principles of information collection, storage and dissemination, involving billions of readers in the discussion of global issues. Mastering the word is not an easy task if the author of the publication is not well-read, is not deep in the topic, does not know the psychology of the audience for which he writes. Therefore, the study of media broadcasting is an important component of the professional training of future journalists. The functions of the language of the media require the authors to make the right statements and convincing arguments in the text. Journalism education is not only knowledge of imperative and dispositive norms, but also apodictic ones. In practice, this means that there are rules in media creativity that are based on logical necessity. Apodicticity is the first sign of impressive language on the platform of print or electronic media. Social expression is a combination of creative abilities and linguistic competencies that a journalist realizes in his activity. Creative self-expression is realized in a set of many important factors in the media: the choice of topic, convincing arguments, logical presentation of ideas and deep philological education. Linguistic art, in contrast to painting, music, sculpture, accumulates all visual, auditory, tactile and empathic sensations in a universal sign – the word. The choice of the word for the reproduction of sensory and semantic meanings, its competent use in the appropriate context distinguishes the journalist-intellectual from other participants in forums, round tables, analytical or entertainment programs. Expressive speech in the media is a product of the intellect (ability to think) of all those who write on socio-political or economic topics. In the same plane with him – intelligence (awareness, prudence), the first sign of which (according to Ivan Ogienko) is a good knowledge of the language. Intellectual language is an important means of organizing a journalistic text. It, on the one hand, logically conveys the author’s thoughts, and on the other – encourages the reader to reflect and comprehend what is read. The richness of language is accumulated through continuous self-education and interesting communication. Studies of social expression as an important factor influencing the formation of public consciousness should open up new facets of rational and emotional media broadcasting; to trace physical and psychological reactions to communicative mimicry in the media. Speech mimicry as one of the methods of disguise is increasingly becoming a dangerous factor in manipulating the media. Mimicry is an unprincipled adaptation to the surrounding social conditions; one of the most famous examples of an animal characterized by mimicry (change of protective color and shape) is a chameleon. In a figurative sense, chameleons are called adaptive journalists. Observations show that mimicry in politics is to some extent a kind of game that, like every game, is always conditional and artificial.

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