Literatura académica sobre el tema "Normal observer"
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Artículos de revistas sobre el tema "Normal observer"
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Röbenack, Klaus. "High Gain Observers Using an Approximate Observer Normal Form". PAMM 6, n.º 1 (diciembre de 2006): 837–38. http://dx.doi.org/10.1002/pamm.200610398.
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Peters, Megan y Hakwan Lau. "Bayesian ideal observer predicts weak forms of blindsight in normal observers". Journal of Vision 15, n.º 12 (1 de septiembre de 2015): 181. http://dx.doi.org/10.1167/15.12.181.
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Tami, Ramdane, Gang Zheng, Driss Boutat, Didier Aubry y Haoping Wang. "Partial observer normal form for nonlinear system". Automatica 64 (febrero de 2016): 54–62. http://dx.doi.org/10.1016/j.automatica.2015.10.041.
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Rudolph, J. y M. Zeitz. "A block triangular nonlinear observer normal form". Systems & Control Letters 23, n.º 1 (julio de 1994): 1–8. http://dx.doi.org/10.1016/0167-6911(94)90075-2.
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Hou, M., Th Schmidt, R. Schu¨pphaus y P. C. Mu¨ller. "Normal Form and Luenberger Observer for Linear Mechanical Descriptor Systems". Journal of Dynamic Systems, Measurement, and Control 115, n.º 4 (1 de diciembre de 1993): 611–20. http://dx.doi.org/10.1115/1.2899188.
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Normal forms are presented for linear mechanical systems with holonomic and/or nonholonomic constraints. These forms provide deep insight into the peculiar system structure of constrained linear mechanical systems or the so-called linear mechanical descriptor systems. Based on these normal forms, an explicit observer design method is proposed under a weaker observability assumption, i.e., finite observability or reachable observability on the linear mechanical descriptor systems. The observer has the Luenberger observer form and provides the estimation of displacements, velocities, and constraint forces simultaneously. The finite observability is shown to be a necessary and sufficient condition for the existence of this type of observer. The reason for the existence of the Luenberger observers for finitely observable linear mechanical descriptor systems is due to the special system structure. Two examples are included to illustrate the design method.
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Boutat, D. y M. Saif. "Nonlinear Observer Normal Forms for Some Predator-Prey Models". IFAC Proceedings Volumes 46, n.º 23 (2013): 682–87. http://dx.doi.org/10.3182/20130904-3-fr-2041.00021.
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Huh, Kunsoo y J. L. Stein. "Well-Conditioned Observer Design for Observer-Based Monitoring Systems". Journal of Dynamic Systems, Measurement, and Control 117, n.º 4 (1 de diciembre de 1995): 592–99. http://dx.doi.org/10.1115/1.2801119.
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Observer-based monitoring systems for machine diagnostics and control are receiving increased attention. These observer techniques can estimate process and machine variables from inexpensive, easy to install remote sensors based on state-space models of the machine structure between the machine variables of interest and the location of the remote sensors. Unfortunately, these observers can be ill-conditioned and this leads to poor performance. The authors have previously shown that observer performance can be represented by a single performance index, the condition number of the eigensystem of the state observer matrix and that there exists an upper bound for the index in non-normal matrices and the bound can be determined by the structure and eigenvalues of the observer matrix. In this paper, a design methodology for synthesizing well-conditioned observers is proposed based on the upper bound of the performance index. The methodology is based on the fact that a small upper bound guarantees small values of the performance index. A well-conditioned matrix form is defined and a block-by block design strategy to produce a well-conditioned observer matrix is presented. A complete design procedure for well-conditioned deterministic state observers is given for the single-output case. The design strategy is illustrated with an example that shows that the proposed well-conditioned observer performs much better than an observer designed with traditional pole placement techniques.
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Tami, R., D. Boutat y G. Zheng. "Nonlinear observer normal form with output injection and extended dynamic". IFAC Proceedings Volumes 46, n.º 23 (2013): 670–75. http://dx.doi.org/10.3182/20130904-3-fr-2041.00117.
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Röbenack, Klaus. "An Approximation of Normal Form Observer Design: Convergence and Computation". IFAC Proceedings Volumes 37, n.º 13 (septiembre de 2004): 1353–58. http://dx.doi.org/10.1016/s1474-6670(17)31416-7.
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Huang, Liuqing y Yiannis Aloimonos. "How normal flow constrains relative depth for an active observer". Image and Vision Computing 12, n.º 7 (septiembre de 1994): 435–45. http://dx.doi.org/10.1016/0262-8856(94)90027-2.
Texto completoTesis sobre el tema "Normal observer"
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Falkenberg, Helle Kristine. "An ideal observer approach to development of motion perception in normal and abnormal vision". Thesis, Glasgow Caledonian University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.416577.
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Bernard, Pauline. "Synthèse d'observateur pour systèmes non linéaires". Thesis, Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLEM010/document.
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Contrairement aux systèmes linéaires, il n’existe pas de méthode systématique pour la synthèse d’observateurs pour systèmes non linéaires. Cependant, la synthèse peut être plus ou moins simple suivant les coordonnées choisies pour exprimer la dynamique. Des structures particulières, appelées formes canoniques, ont notamment été identifiées comme permettant la construction facile et directe d’un observateur. Une façon usuelle de résoudre ce problème consiste donc à chercher un changement de coordonnées réversible transformant l’expression de la dynamique dans l’une de ces formes canoniques, puis à synthétiser l’observateur dans ces coordonnées, et enfin à en déduire une estimation de l’état du système dans les coordonnées initiales par inversion de la transformation. Cette thèse contribue à chacune de ces trois étapes. Premièrement, nous montrons l’intérêt d’une nouvelle forme triangulaire avec des non linéarités continues (non Lipschitz). En effet, les systèmes observables pour toutes entrées, mais dont l'ordre d’observabilité différentielle est supérieur à la dimension du système, peuvent ne pas être transformables dans la forme triangulaire Lipschitz standard, mais plutôt dans une forme triangulaire "seulement continue". Le célèbre observateur grand gain n’est alors plus suffisant, et nous proposons d’utiliser plutôt des observateurs homogènes.Une autre forme canonique intéressante est la forme linéaire Hurwitz, qui admet un observateur trivial. La question de la transformation d’un système non linéaire dans une telle forme n’a été étudiée que pour les systèmes autonomes à travers les observateurs de Kazantzis-Kravaris ou de Luenberger. Nous montrons ici comment cette synthèse, consistant à résoudre une EDP, peut être étendue aux systèmes instationnaires/commandés. Quant à l’inversion de la transformation, cette étape est loin d’être triviale en pratique, surtout lorsque les espaces de départ et d’arrivée ont des dimensions différentes. En l’absence d’expression explicite et globale de l’inverse, l’inversion numérique repose souvent sur la résolution d’un problème de minimisation couteux en calcul. C’est pourquoi nous développons une méthode qui permet d’éviter l’inversion explicite de la transformation en ramenant la dynamique de l’observateur (exprimée dans les coordonnées de la forme canonique) dans les coordonnées initiales du système. Ceci passe par l’ajout de nouvelles coordonnées et par l’augmentation d’une immersion injective en un difféomorphisme surjectif. Enfin, dans une partie totalement indépendante, nous proposons aussi des résultats concernant l’estimation de la position du rotor d’un moteur synchrone à aimant permanent en l’absence d’informations mécaniques (sensorless) et lorsque des paramètres tels que la résistance ou le flux de l’aimant sont inconnus. Ceci est illustré par des simulations sur données réellesUnlike for linear systems, no systematic method exists for the design of observers for nonlinear systems. However, observer design may be more or less straightforward depending on the coordinates we choose to express the system dynamics. In particular, some specific structures, called canonical forms, have been identified for allowing a direct and easier observer construction. It follows that a common way of addressing the problem consists in looking for a reversible change of coordinates transforming the exression of the system dynamics into one of those canonical forms, design an observer in those coordinates, and finally deduce an estimate of the system state in the initial coordinates via inversion of the transformation. This thesis contributes to each of those three steps.First, we show the interest of a new triangular canonical form with continuous (non-Lipschitz) nonlinearities. Indeed, we have noticed that systems which are observable for any input but with an order of differential observability larger than the system dimension, may not be transformable into the standard Lipschitz triangular form, but rather into an "only continuous" triangular form. In this case, the famous high gain observer no longer is sufficient, and we propose to use homogeneous observers instead.Another canonical form of interest is the Hurwitz linear form which admits a trivial observer. The question of transforming a nonlinear system into such a form has only been addressed for autonomous systems with the so-called Lunberger or Kazantzis-Kravaris observers. This design consists in solving a PDE and we show here how it can be extended to time-varying/controlled systems.As for the inversion of the transformation, this step is far from trivial in practice, in particular when the domain and image spaces have different dimensions. When no explicit expression for a global inverse is available, numerical inversion usually relies on the resolution of a minimization problem with a heavy computational cost. That is why we develop a method to avoid the explicit inversion of the transformation by bringing the observer dynamics (expressed in the canonical form coordinates) back into the initial system coordinates. This is done by dynamic extension, i-e by adding some new coordinates to the system and augmenting an injective immersion into a surjective diffeomorphism.Finally, in a totally independent part, we also provide some results concerning the estimation of the rotor position of a permanent magnet synchronous motors without mechanical information (sensorless) and when some parameters such as the magnet flux or the resistance are unknown. We illustrate this with simulations on real data
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Jakobsson, Tell. "Lactobacillus iners and the normal vaginal flora". Doctoral thesis, Linköping : Department of Clinical and Experimental Medicine, Linköping University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-11334.
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Léonard, Guillaume. "Observer pour agir: Une étude comparative de la facilitation motrice liée à l'observation, l'imagerie et l'imitation d'actions dans le vieillissement normal et la maladie de Parkinson". Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27265.
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L'objectif du présent travail était de déterminer et de comparer le patron de modulation de l'excitabilité corticomotrice lié à l'observation, l'imagerie et l'imitation d'actions chez les jeunes âges de moins de 30 ans (n=21), les personnes âgées de plus de 55 ans (n=19) et les personnes atteintes de la maladie de Parkinson (MP) (n=11). L'action présentée sur un écran d'ordinateur 17" illustrait la main d'une personne coupant une pièce de matériel à l'aide d'une paire de ciseaux. Les potentiels moteurs évoqués induits à l'aide de la stimulation magnétique transcrânienne étaient mesurés dans le premier interosseux dorsal (FDI) et dans le court abducteur du cinquième doigt (ADM) dans quatre conditions: (1) repos, (2) observation de l'action, (3) imagerie motrice de l'action et (4) imitation de l'action. Chez les jeunes participants, l'imitation produisait la plus grande facilitation lorsque comparée au repos, suivi de l'observation et de l'imagerie qui induisaient des facilitations comparables. Ces facilitations étaient sélectives au muscle FDI puisque, dans le muscle ADM, seule l'imitation était associée à une facilitation corticomotrice. Chez les personnes âgées, le patron de facilitations était relativement semblable à celui observé chez les jeunes, à la différence que les facilitations notées dans le FDI étaient aussi présentes dans l'ADM. Quant aux patients avec la MP, les facilitations associées aux conditions d'observation et d'imagerie se sont avérées variables et inconsistantes par rapport aux personnes contrôlés du même âge. La diminution de la sélectivité chez les personnes âgées ainsi que les déficits des facilitations clicz les personnes atteintes de la MP cadrent bien avec la théorie de simulation motrice proposée par Jeannerod (2001). En effet, de tels déficits sont similaires à ceux observés chez ces populations lors de l'exécution réelle (notamment une diminution de la dextérité manuelle chez les personnes âgées et des troubles d'activation motrice chez les personnes atteintes de la MP) et appuient donc l'hypothèse selon laquelle il existerait une équivalence au niveau neural entre les états associés à la production d'actions motrices, que celles-ci soient exécutées réellement, simplement observées ou simulées mentalement.
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Hoang, Trong bien. "Switched observers and input-delay compensation for anti-lock brake systems". Phd thesis, Université Paris Sud - Paris XI, 2014. http://tel.archives-ouvertes.fr/tel-00994114.
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Many control algorithms for ABS systems have been proposed in the literature since the introduction of this equipment by Bosch in 1978. In general, one can divide these control algorithms into two different types: those based on a regulation logic with wheel acceleration thresholds that are used by most commercial ABS systems; and those based on wheel slip control that are preferred in the large majority of academic algorithms. Each approach has its pros and cons [Shida 2010]. Oversimplifying, one can say that the strength of the first ones is their robustness; while that of the latter ones their short braking distances (on dry grounds) and their absence of limit cycles. At the midpoint of this industry/academy dichotomy, based on the concept of extended braking stiffness (XBS), a quite different class of ABS control strategies has been proposed by several researchers (see, e.g., [Sugai 1999] and [Ono 2003]). This concept combines the advantages from both the industrial and academic approaches. Nevertheless, since the slope of the tyre characteristic is not directly measurable, it introduces the question of real-time XBS estimation. The first part of this thesis is devoted to the study of this estimation problem and to a generalization of the proposed technique to a larger class of systems. From the technological point of view, the design of ABS control systems is highly dependent on the ABS system characteristics and actuator performance. Current ABS control algorithms on passenger cars, for instance the Bosch ABS algorithm, are based on heuristics that are deeply associated to the hydraulic nature of the actuator. An interesting observation is that they seem to work properly only in the presence of a specific delay coming from the hydraulic actuation [Gerard 2012]. For brake systems that have different delays compared to those of hydraulic actuators, like electric in-wheel motors (with a smaller delay) or pneumatic trailer brakes (with a bigger delay), they might be no longer suitable [Miller 2013]. Therefore, adapting standard ABS algorithms to other advanced actuators becomes an imperative goal in the automobile industry. This goal can be reached by the compensation of the delays induced by actuators. The second part of this thesis is focused on this issue, and to the generalization of the proposed technique to a particular class of nonlinear systems. Throughout this thesis, we employ two different linearization techniques: the linearization of the error dynamics in the construction of model-based observers [Krener 1983] and the linearization based on restricted state feedback [Brockett 1979]. The former is one of the simplest ways to build an observer for dynamical systems with output and to analyze its convergence. The main idea is to transform the original nonlinear system via a coordinate change to a special form that admits an observer with a linear error dynamics and thus the observer gains can be easily computed to ensure the observer convergence. The latter is a classical method to control nonlinear systems by converting them into a controllable linear state equation via the cancellation of their nonlinearities. It is worth mentioning that existing results for observer design by error linearization in the literature are only applied to the case of regular time scalings ([Guay 2002] and [Respondek 2004]). The thesis shows how to extend them to the case of singular time scalings. Besides, the thesis combines the classical state feedback linearization with a new method for the input delay compensation to resolve the output tracking problem for restricted feedback linearizable systems with input delays.
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Dziengel, Norman [Verfasser]. "Distributively Observed Events in Wireless Sensor Networks / Norman Dziengel". Berlin : Freie Universität Berlin, 2016. http://d-nb.info/1095540157/34.
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Tami, Ramdane. "Formes normales d'observabilité : étendue, partielle et réduite". Thesis, Orléans, 2014. http://www.theses.fr/2014ORLE2039.
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L'observateur est un outil essentiel pour accéder à l'information, non mesurable directement, d'un système dynamique. Dans le cas des systèmes non linéaires, il y a une grande carence concernant la synthèse d'observateur. Motivée par l'absence d'une solution générique, cette thèse élargit la classe des systèmes non linéaires pour lesquels on peut appliquer les observateurs connus. Dans l'approche adoptée, le système non linéaire est transformé à travers un changement de coordonnées sous forme normale d'observabilité qui a une structure adéquate à la synthèse d'observateurs. Les difficultés liées aux conditions d'existence d'un changement de coordonnées sont mises en évidence et des solutions sont proposées. Par conséquent, la classe des systèmes non linéaires qui peuvent se mettre sous une forme normale d'observabilité est élargie. Dans un premier temps, nous avons proposé une forme normale d'observabilité étendue dépendante de la sortie en augmentant l'espace d'état par des variables auxiliaires. Ainsi, nous avons établi les conditions nécessaires et suffisantes à l'existence d’un changement de coordonnées permettant d’obtenir une telle forme. En outre, nous avons proposé, pour certains modèles, des procédures heuristiques pour la mise sous forme normale d'observabilité étendue dépendante de la sortie. Dans un deuxième temps, nous avons traité la mise sous forme normale d'observabilité d'un système non linéaire partiellement observable. Enfin, nous avons abordé la transformation d'une classe spéciale de systèmes non linéaires sous la forme normale d'observabilité réduite. L'efficacité et l'intérêt des méthodes développées sont établis au travers de plusieurs applicationsObserver is an essential means to access to no-measurable information of a dynamical system. In the case of nonlinear systems, there is a great deficiency concerning the observer design theory. Motivated by the lack of a generic solution to observer design, this thesis enlarges the class of nonlinear systems which admit a standard observer. Using a geometrical approach, the considered nonlinear systems are transformed through a change of coordinates into observer form, which has an adequate structure to the observer design. The difficulties related to the conditions on the existence of such a change of coordinates are highlighted and solutions are proposed. Therefore, the class of nonlinear systems which can be transformed under an observer form is expanded. Firstly, we proposed an extended output depending observer form which does not preserve the size of the original state space and we established the sufficient conditions for the existence of a change of coordinates enabling to construct the proposed form. Moreover, we proposed a heuristic procedure to construct the extended output depending observer form of some models. Secondly, we dealt with the observer form for some partially observable nonlinear systems. Finally, we discussed the transformation into the reduced observer form for a class of nonlinear systems. The efficiency and interest of the developed methods is established through several applications
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Pescim, Rodrigo Rossetto. "The new class of Kummer beta generalized distributions: theory and applications". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/11/11134/tde-30012014-112231/.
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In this study, a new class of generalized distributions was developed, based on the Kummer beta distribution (NG; KOTZ, 1995), which contains as particular cases the exponentiated and beta generators of distributions. The main feature of the new family of distributions is to provide greater flexibility to the extremes of the density function and therefore, it becomes suitable for analyzing data sets with high degree of asymmetry and kurtosis. Also, two new distributions belonging to the new class of distributions, based on the Birnbaum-Saunders and generalized gamma distributions, that has as main characteristic the hazard function which assumes different forms (unimodal, bathtub shape, increase, decrease) were studied. In all studies, general mathematical properties such as ordinary and incomplete moments, generating function, mean deviations, reliability, entropies, order statistics and their moments were discussed. The estimation of parameters is approached by the method of maximum likelihood and Bayesian analysis and the observed information matrix is derived. It is also considered the likelihood ratio statistics and formal goodness-of-fit tests to compare all the proposed distributions with some of its sub-models and non-nested models. The developed results for all studies were applied to six real data sets.Neste trabalho, foi proposta uma nova classe de distribuições generalizadas, baseada na distribuição Kummer beta (NG; KOTZ, 1995), que contém como casos particulares os geradores exponencializado e beta de distribuições. A principal característica da nova família de distribuições é fornecer grande flexibilidade para as extremidades da função densidade e portanto, ela torna-se adequada para a análise de conjuntos de dados com alto grau de assimetria e curtose. Também foram estudadas duas novas distribuições que pertencem à nova família de distribuições, baseadas nas distribuições Birnbaum-Saunders e gama generalizada, que possuem função de taxas de falhas que assumem diferentes formas (unimodal, forma de banheira, crescente e decrescente). Em todas as pesquisas, propriedades matemáticas gerais como momentos ordinários e incompletos, função geradora, desvios médio, confiabilidade, entropias, estatísticas de ordem e seus momentos foram discutidas. A estimação dos parâmetros é abordada pelo método da máxima verossimilhança e pela análise bayesiana e a matriz de informação observada foi derivada. Considerou-se, também, a estatística de razão de verossimilhanças e testes formais de qualidade de ajuste para comparar todas as distribuições propostas com alguns de seus submodelos e modelos não encaixados. Os resultados desenvolvidos foram aplicados a seis conjuntos de dados.
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Buchs, Arnaud. "Observer, caractériser et comprendre la pénurie en eau : une approche institutionnaliste de l'évolution du mode d'usage de l'eau en Espagne et au Maroc". Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00703273.
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Ce mémoire de thèse a pour objet la pénurie en eau. Face aux analyses techniques a-historiques centrées sur la rareté physique de l'eau, nous développons une problématique sociale-contingente pour laquelle les usages de l'eau sont au cœur de l'explication. La première partie correspond à l'étape d'observation. Elle a pour objectif de retracer l'évolution du mode d'usage de l'eau à Almeria (Andalousie) et à Marrakech et Agadir (Maroc) entre la fin du XIXe siècle et aujourd'hui. Considéré comme domaine d'observation, le mode d'usage de l'eau (Arrus) qualifie l'articulation d'un volet " économique ", relatif à l'ajustement réciproque de l'offre et des usages finals de l'eau produite (formalisé par des normes-procédures) et d'un volet " institutionnel ", relatif aux normes sociales (qualifiées de normes-règles) présidant à la définition des droits de disposition sur les ressources en eau. Pour chacun des trois terrains, cette étape comprend une étude de terrain qualitative combinée à une analyse historiographique et à une analyse textuelle de documents de planification selon la méthode Alceste. Cette étape débouche sur la formulation de quatre faits stylisés chronologiques traduisant la succession de quatre phases constitutives du cycle de vie d'un mode d'usage de l'eau particulier. La deuxième partie est d'ordre théorique. Elle correspond aux étapes de caractérisation et de compréhension. Ces deux étapes reposent sur la mobilisation d'une grille théorique nouvelle élaborée par Billaudot sur la base d'une mise en rapport de l'institutionnalisme de Commons et de l'institutionnalisme sociologique de l'approche interprétative de l'économie des conventions (Boltanski et Thévenot). Qualifiée d'institutionnalisme historique et pragmatique, cette approche se présente comme une perspective d'approfondissement de l'institutionnalisme historique de la théorie de la régulation. Elle a pour objectif d'articuler genèse et fonction des institutions et conduit notamment à associer à chacune des modalités de règlement des transactions de Commons une valeur de référence et un bien supérieur. Ainsi, le mode d'usage de l'eau particulier ayant connu une phase de régime en Espagne et au Maroc au cours de la seconde moitié du XXe siècle est qualifié d'" hydrauliciste ". Il se caractérise par une représentation de l'eau essentiellement comme ressource d'allocation, dont l'abondance obtenue par des infrastructures à haute intensité de génie civil constitue une des prérogatives de l'État " moderne " qui, en aval, régit également son usage. L'identification des principales caractéristiques du mode d'usage " hydrauliciste " permet d'aboutir à la troisième étape, à savoir la compréhension des déterminants de son entrée en crise à partir des années 1980. D'une part, cette crise porte sur l'arrivée à terme des régularités antérieures quant à l'ajustement réciproque de l'offre et des usages finals de l'eau produite : on constate une raréfaction des ressources primaires (on qualifie cet aspect de " crise de la régulation "). D'autre part, elle correspond à la remise en question du cadre institutionnel qui soutient le volet économique (on constate une " crise du fondement du régime "). Ainsi, les normes sont partiellement disqualifiées par un double processus de délocalisation en faveur d'une décentralisation de la gestion de l'eau. De plus, le caractère non soutenable du mode d'usage antérieur conduit à l'émergence d'aspirations écologistes concrétisées par la proposition de nouvelles normes d'usage. Le registre de socialisation écologique pour lequel l'eau est comprise comme un milieu de vie se renforce. Au final, nous aboutissons à l'identification d'un nouveau mode d'usage actuellement en vigueur. Nous montrons qu'il ne procède pas d'une rupture paradigmatique mais correspond à un " régime de crise ".
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Filali, Rania Linda. "Sur la synchronisation et le cryptage de systèmes chaotiques à temps discret utilisant les techniques d'agrégation et la représentation en flèche des matrices". Phd thesis, Ecole Centrale de Lille, 2013. http://tel.archives-ouvertes.fr/tel-00858272.
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L'objectif de cette thèse était de développer une méthode de synthèse de commande par retour d'état puis par observateurs offrant des conditions de synthèse non contraignantes dans le cas de systèmes non linéaires à temps discret. Dans cette méthode, est mise en exergue l'importance du choix de la description des systèmes sur l'étendue des résultats pouvant être obtenus lorsque la méthode d'étude de la stabilité est fixée. Ainsi l'utilisation des normes vectorielles comme fonction d'agrégation et du critère pratique de Borne et Gentina pour l'étude de la stabilité, associée à la description des systèmes par des matrices caractéristiques de forme en flèche de Benrejeb, a conduit à l'élaboration de nouvelles conditions suffisantes de stabilisation de systèmes dynamiques discrets non linéaires, formulées en théorèmes et corollaires. Ces résultats obtenus, sont ensuite exploités, avec succès, pour la formulation de nouvelles conditions suffisantes de vérification des propriétés de synchronisation pour les systèmes hyperchaotiques à temps discrets. Ensuite, le cas de synthèse d'observateur est validé dans deux types de transmission chaotique
Libros sobre el tema "Normal observer"
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National Research Council (U.S.), ed. National Science Education Standards: Observe, interact, change, learn. Washington, DC: National Academy Press, 1996.
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Canada. Dept. of Foreign Affairs and International Trade. Labour : Convention Concerning Minimum Standards in Merchant Ships (ILO No. 147), Geneva, October 29, 1976, ratified by Canada May 25, 1993, in force for Canada May 25, 1994 =: Travail : Convention concernant les normes minima à observer sur les navires marchands (OIT No 147), Genève, le 29 octobre 1976, ratification du Canada le 25 mai 1993, en vigueur pour le Canada le 25 mai 1994. Ottawa, Ont: Queen's Printer = Imprimeur de la Reine, 1997.
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Papsin, Blake Croll. Auditory temporal integration in normal and hearing-impaired observers. 1985.
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Woods, Charles Barrie. Color discrimination and color-opponent strength in normal, protan, and deutan observers. 1990.
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Yin Li, Eva Cheuk. Desiring Queer, Negotiating Normal. Hong Kong University Press, 2018. http://dx.doi.org/10.5790/hongkong/9789888390809.003.0008.
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This chapter explores the entanglement between queer desires and struggles with normativities in fandoms through the case study of Denise Ho (a.k.a. HOCC) in Hong Kong. HOCC is one of the few celebrities in the Chinese-language entertainment industry to have come out as a lesbian. Data is drawn from participant observation and semi-structured interviews with 29 fans between 2009 and 2014. By analyzing the interplay between Hong Kong sexual cultures, fans’ everyday lives, and fans’ interactions with global media, it is found that fans struggled with negotiating HOCC’s gender and sexuality and their own before HOCC’s coming-out, leading to the paradoxical celebration and self-policing of queer reading at the same time. HOCC’s coming out in 2012 has significantly reshaped her queer fandom. It is observed that fans have turned their attention to the negotiation of HOCC’s “proper” lesbian embodiment as the “correct” representation of the LGBT/tongzhi movement. By revealing the complex relations between heteronormativity and homonormativity, this chapter concludes that HOCC fans in Hong Kong, who are situated within macrostructural and micropolitical forces, desire to be queer by transgressing normal and paradoxically desire to be normal by tactically negotiating the limits of queer.
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Schroeder, Charles E., Jose L. Herrero y Saskia Haegens. Neuronal Dynamics and the Mechanistic Bases of Selective Attention. Editado por Anna C. (Kia) Nobre y Sabine Kastner. Oxford University Press, 2014. http://dx.doi.org/10.1093/oxfordhb/9780199675111.013.031.
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Selective attention is a process by which the brain enhances its representation of task relevant, over irrelevant information. This ‘active control’ is essential to normal perception and cognition because it enables information processing to adapt to the immediate goals of the observer. This chapter places the focuses on recent conceptual/empirical developments in four areas that the authors think have significantly advanced the discussion and debate on the mechanistic underpinnings of selective attention: (1) the role of neuronal oscillations, (2) the distinctions between differing modes of dynamic operation, (3) potentially unique roles of specific oscillatory frequencies, (4) the neurochemistry of attention. The authors end by replacing attention within an ‘active sensing’ framework, and posing a set of prime questions for future study.
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Sutcliffe-Braithwaite, Florence. Mass Observers’ Attitudes to Class, 1990. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198812579.003.0006.
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This chapter uses responses to Mass Observation’s 1990 directive on ‘social divisions’ to examine what the Mass Observers thought about class. It concludes that earlier accounts have overstated these (largely middle-class) writers’ comfortableness with technical, sociological class language. Rather, many were hostile to or ambivalent about using such terms, and drew on popular culture, especially humour, when talking about class. A rejection of ‘class’ and snobbishness, and an emphasis on ordinariness and authenticity, were again central to many Mass Observers’ writings about class. In their testimonies, we can also see that new ethnic diversity and new, more diverse norms of gender in post-war Britain had disrupted the old class categories. Upwardly mobile people were particularly over-represented among the Mass Observers and their writing shows that upward social mobility—which expanded in the post-war decades—could lead to a cultural ‘homelessness’ and critiques of both traditional working-class and traditional middle-class cultures.
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Hanau, Hans y Wenzel Matiaske, eds. Entgrenzung von Arbeitsverhältnissen. Nomos Verlagsgesellschaft mbH & Co. KG, 2019. http://dx.doi.org/10.5771/9783845296159.
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For about a quarter of a century, social sciences have been a keen observer of the transformations of labor relations within organizations, which can readily subsumed under the term of ‘dissolution of boundaries’. This ongoing decentralization of the organization, spanning from outsourcing over strategic alliances to networks, has been accompanied by the flexibilization and subjectivization of work. What initially occurred in the periphery of large organizations, soon became the “new normal” for the core work force across the economy, for the core relationships of gainful employment. Organizational sciences, essentially belonging the most ardent promoters of the abovementioned developments, came to realize that some of their brainchildren, especially the “boundaryless organization”, might constitute an existential threat to the own discipline. Meanwhile, the dissolution of boundaries of working relations was not only eagerly discussed but also widely advocated in the subdiscipline of human resource management. As a result, key terms and notions of labor law (e.g. ‘firm‘, employee’ or ‘employer’) became blurred and now suffer from impaired relevance and effectiveness with regard to their legal protective functions and autonomy of bargaining. This edited volume aims to inspire and deepen a debate that moves beyond disciplinary boundaries. Some urgency is given, because at the end of the day, nothing else but the constitution of the social market economy is at stake.
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Dunne, Tim y Eglantine Staunton. The Genocide Convention and Cold War Humanitarian Intervention. Editado por Alex J. Bellamy y Tim Dunne. Oxford University Press, 2016. http://dx.doi.org/10.1093/oxfordhb/9780198753841.013.3.
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It is conventional in IR literature to observe a sharp break between the Cold War and post-Cold War phases in the evolution of human protection norms. The chapter revisits these arguments in conjunction with the cases of India in Pakistan, Vietnam in Cambodia, and Tanzania in Uganda, where unilateral interventions had humanitarian effects but neither humanitarian justifications nor external legitimation. The predominant view regarding these cases is correct; namely, no evidence can be found for the emergence of a norm of legitimate intervention for protection reasons (in the absence of host state consent). However, this perspective underestimates the extent to which there was a consolidation of norms regarding state responsibilities and how these influenced state practice during the post-1945 period. The end of the Cold War should be seen as less of a stark turning point in the history of responsible sovereignty than has previously been believed.
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Goode, Erich. The Taming of New York's Washington Square. NYU Press, 2018. http://dx.doi.org/10.18574/nyu/9781479878574.001.0001.
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This book addresses the matter of how social audiences, both formal agents of social control (the NYPD and the Park Enforcement Control) and the ordinary, everyday park-goer, react when they encounter what they consider wrongdoing, or “deviance.” The focus is on the micro or face-to-face interactional level; the larger structural forces are held in abeyance and assumed to operate, but they are not analysed or accounted for here. Likewise, literary and philosophical speculations as well as considering political and ideological implications have been left to other analysts. What constitutes deviance in an unconventional public setting remains the central issue throughout the volume. Visitors to the park—one that is known for celebrating difference and diversity—observe behaviour or utterances by an actor or a speaker in their presence that, they feel goes too far in violating their sense of acceptable norms. What do they do? How do they sanction the offender? The analysis in this book presents the reader with a series of anecdotes—events or episodes observed or statements overheard by the researcher that audiences, judging by their reactions, consider untoward. The action-reaction-interaction dynamics constitutes the lodestone of this volume. Washington Square Park is a “text”; this book represents a sociological “reading” of that text.
Capítulos de libros sobre el tema "Normal observer"
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Bernard, Pauline. "State-Affine Normal Forms". En Observer Design for Nonlinear Systems, 21–27. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-11146-5_3.
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Boutat, Driss y Gang Zheng. "Output-Depending Observer Normal Form". En Observer Design for Nonlinear Dynamical Systems, 107–26. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-73742-9_6.
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Bernard, Pauline. "Transformations into State-Affine Normal Forms". En Observer Design for Nonlinear Systems, 53–73. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-11146-5_6.
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Boutat, Driss y Gang Zheng. "Observer Normal Form with Output Injection". En Observer Design for Nonlinear Dynamical Systems, 55–68. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-73742-9_3.
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Schaffner, J. y M. Zeitz. "Variants of nonlinear normal form observer design". En New Directions in nonlinear observer design, 161–80. London: Springer London, 1999. http://dx.doi.org/10.1007/bfb0109926.
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Boutat, Driss y Gang Zheng. "Observer Normal Form by Means of Extended Dynamics". En Observer Design for Nonlinear Dynamical Systems, 91–106. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-73742-9_5.
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Boutat, Driss y Gang Zheng. "Observer Normal Form with Output Injection and Output Diffeomorphism". En Observer Design for Nonlinear Dynamical Systems, 69–89. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-73742-9_4.
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Goel, P. S., K. S. Chandra y P. Kudva. "Observer Based Design of Normal Mode Attitude Control for IRS Satellite". En Astrophysics and Space Science Library, 327–34. Dordrecht: Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-009-4732-0_31.
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He, Ruili, Min Huang, Chunjie Shi, Bingjie Shi, Peipei Ran y Yusheng Lian. "Comparison of Two Methods for Color-Normal Observer Variability in Color Discrimination". En Lecture Notes in Electrical Engineering, 133–40. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-10-7629-9_17.
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Tanner, Martin A. "Observed Data Techniques-Normal Approximation". En Tools for Statistical Inference, 6–15. New York, NY: Springer New York, 1991. http://dx.doi.org/10.1007/978-1-4684-0510-1_2.
Texto completoActas de conferencias sobre el tema "Normal observer"
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Saadi, Wided, Driss Boutat, Gang Zheng y Lassaad Sbita. "Multi-output partial nonlinear observer normal form". En 2015 54th IEEE Conference on Decision and Control (CDC). IEEE, 2015. http://dx.doi.org/10.1109/cdc.2015.7403429.
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Massanes, Francesc y Alexander H. Vija. "Class classification using two alternate force choice against an ensemble of normal examples". En Image Perception, Observer Performance, and Technology Assessment, editado por Frank W. Samuelson y Sian Taylor-Phillips. SPIE, 2021. http://dx.doi.org/10.1117/12.2582119.
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Zhang, Yandong y S. C. Sinha. "Observer Design for Nonlinear Systems With Time Periodic Coefficients Via Normal Form Theory". En ASME 2007 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/detc2007-34831.
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For most complex dynamic systems, it is not possible to measure all system states in a direct fashion. Thus for dynamic characterization and controller design purposes, it is often necessary to design an observer in order to get an estimate of those states which cannot be measured directly. In this work, the problem of designing state observers for free systems with time periodic coefficients is addressed. For linear time-periodic systems, it is shown that the observer design problem is the duality of the controller design problem. The state observer is constructed using a symbolic controller design method developed earlier using the Chebyshev expansion technique. For the nonlinear time periodic systems, the observer design is investigated using the Poincare´ normal form technique. The local identity observer is designed by using a set of near identity coordinate transformations which can be constructed in the ascending order of nonlinearity. These observer design methods are implemented using a symbolic computational algorithm and several illustrative examples are given to show the effectiveness of the methods.
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Zhou, Bin y Guang-Ren Duan. "Parametric Approach for the Normal Luenberger Function Observer Design in Second-order Linear Systems". En Proceedings of the 45th IEEE Conference on Decision and Control. IEEE, 2006. http://dx.doi.org/10.1109/cdc.2006.377465.
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Lakshminarayanan, Vasudevan, Jay M. Enoch y Shinichi Yamade. "Photoreceptor orientation and directional sensitivity in a unique aniridic observer". En OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1986. http://dx.doi.org/10.1364/oam.1986.tut4.
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Photoreceptor alignment can be studied by measuring the Stiles-Crawford effect (SCE) from which one can infer the principal alignment tendencies and distributive properties of the photoreceptor population being tested. Previously, the SCE has not been studied in aniridia due to its many complications. We present here results of measurements of the SCE in a unique aniridic observer who was tested extensively. SCE functions were obtained at various retinal loci using a two-channel Maxwellian view apparatus. Our results show the presence of secondary side lobes in the SCE function, higher than normal or normal curvatures of the SCE functions at various loci, and receptors aligned approximately toward the center of the retinal sphere. Some anomalies of dark adaptation were noted. This precluded measurement of scotopic SCE in this observer. The implications of these findings are discussed.
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Kawamoto, Atsushi, Mizuho Inagaki, Takayuki Aoyama, Nobuyuki Mori y Kimihiko Yasuda. "Vibration of Moving Flexible Bodies (Formulation of Dynamics by Using Normal Modes and a Local Observer Frame)". En ASME 1999 Design Engineering Technical Conferences. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/detc99/vib-8232.
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Abstract This paper deals with the formulation that can analyze vibration noise problems practically in the flexible multibody systems. Many kinds of formulations have been proposed on the flexible multibody systems so far. They are categorized into several groups according to their purposes and coordinate systems. The floating frame of reference formulation is at present the most popular method for general purpose simulations among them. The formulation uses Cartesian coordinates for the position of a body, Euler angles or Euler parameters for the orientations, and modal coordinates for the elastic degrees of freedom. The equations of motion with these different kinds of coordinates are complicated because of coupling between rigid body motion and elastic vibration. On the other hand, the linear theory of elasto-dynamics appears to be simple and could be practical for some limited uses. But it neglects the effect of the elastic deformation on the rigid body motion. In many cases, the effect is significant and essential. In this paper, we propose a new formulation with rigid body modes and a local observer frame (LOF) for large amplitude rigid body motion, and with elastic modes for small amplitude elastic vibration. The LOF is updated properly to compensate the gap between rigid body motion and the LOF motion. The new formulation makes the coupling terms as simple as possible without any loss of the effect of the elastic deformation on the rigid body motion and gives the uniform description in each modal coordinate.
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Otake, Shiro y Carol M. Cicerone. "The relative numbers of L and M cones and the cone density distribution in the peripheral retina". En OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/oam.1992.tuz8.
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The relative numbers of L and M cones were estimated at the fovea and at temporal 2°, 7°, 17°, and 28° and at nasal 2°, 7°, 28° eccentricity along the horizontal meridian in two color normal observers (methods of Cicerone and Nerger, 1989). Unique hues were also measured at these locations. The total cone density distributions are comparable to anatomical data (Curcio et al.,1990). The relative number of L and M cones remains constant at these eccentricities. One observer’s ratio of 2.00 falls within the range of 1.46 to 2.36 previously measured for nine observers (Cicerone, 1990). Unique yellow measured at the same locations was also constant (about 670 nm) with eccentricity. Another observer with a smaller L to M cone ratio has a unique yellow at a longer wavelength (about 580 nm). These results can be interpreted by assuming that the latter observer has relatively more M cones but has the same neural connections to the red–green opponent system.
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Hajivand, A. y S. H. Mousavizadegan. "The Effect of Memory in Observer Design for a DP System". En ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-38040.
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The behavior of marine structures is investigated in regular waves using various models in frequency and time domains. In normal practice, the differential form of motion equations are used with constant hydrodynamic coefficients. Those coefficients which are added masses and damping coefficients are frequency dependent due to the memory effect. The memory effect is usually represented by a convolution integral and hence it converts the motion equations into integro-differential forms. The presence of the convolution integral makes the equations complex. However, it is necessary to take into account the memory effect in ship motion control and specially in dynamic positioning system to enhance the accuracy and obtained a more precise controller. The motion equations are solved for a DP system with memory effect and compare with the conventional model. The computations show that memory effect is important as the wave frequency increases. A nonlinear observer has been design to solve the wave filtering and state estimation problems with the memory effect. The performance of the nonlinear observer is demonstrated by computer simulations.
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Qin, Jinna, François Léonard y Gabriel Abba. "Non-Linear Observer-Based Control of Flexible-Joint Manipulators Used in Machine Processing". En ASME 2012 11th Biennial Conference on Engineering Systems Design and Analysis. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/esda2012-82048.
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This paper proposes to use a non-linear observer to build the state and the external force of flexible manipulator robots during their machining (composite materials) processes or Friction Stir Welding (FSW) processes. These two different processes have a problem in common: the flexibility of the robot can not be neglected, that is to say, the errors due to the deformation of the links should be taken into account. However, in most industrial robots, the real positions and velocities of each link are not measured, so in this study, an observer is proposed to reconstruct the real angular positions and velocities of links by using the measured angular positions and the velocities of actuators. A simulation by Matlab/Simulink has been carried out with a 2 axis Robot during its machining processes: the proposed observer showed great performances in estimating the state of the robot (position and velocity). Then, in order to improve the tracking accuracy in the tool frame, the state of the external force along the forward direction (x) and its normal direction (y) are required, while they are also not measured by our robot. A disturbance observer has been added to reconstruct the processing force. A good precision during the proposed processes have been obtained using the latter. This study contributes to solve the problem from the point of view of accuracies during the machining processes.
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Koga, Shumon, Leobardo Camacho-Solorio y Miroslav Krstic. "State Estimation for Lithium Ion Batteries With Phase Transition Materials". En ASME 2017 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/dscc2017-5266.
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Lithium Iron Phosphate (LiFePO4 or LFP) is a common active material in lithium-ion batteries. It has been observed that this material undergoes phase transitions during the normal charge and discharge operation of the battery. Electrochemical models of lithium-ion batteries can be modified to account for this phenomena at the expense of some added complexity. We explore this problem for the single particle model (SPM) where the underlying dynamic model for diffusion of lithium ions in phase transition materials is a partial differential equation (PDE) with a moving boundary. An observer is derived for the concentration of lithium ions from the SPM via the backstepping method for PDEs in a rigorous way and simulations are provided to illustrate the performance of the observer. Our comments are stated on the gap between the proposed observer and a complete state-of-charge (SoC) estimation algorithm for lithium-ion batteries with phase transition materials.
Informes sobre el tema "Normal observer"
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Raymond, Kara, Laura Palacios y Evan Gwilliam. Status of climate and water resources at Big Bend National Park: Water year 2019. Editado por Tani Hubbard. National Park Service, septiembre de 2022. http://dx.doi.org/10.36967/2294267.
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Climate and hydrology are major drivers of ecosystem structure and function, particularly in arid and semi-arid ecosystems. Understanding changes in climate, groundwater, streamflow, and water quality is central to assessing the condition of park resources. This report combines data collected on climate, groundwater, and springs at Big Bend National Park (NP) to provide an integrated look at climate and water conditions during water year (WY) 2019 (October 2018–September 2019). However, this report does not address the Rio Grande or its tributaries. Annual precipitation was higher than normal (1981–2010) for Big Bend NP at four of the five National Oceanic and Atmospheric Administration Cooperative Observer Program weather stations: 111% of normal for Chisos Basin, 122% of normal for Panther Junction, 155% of normal for Persimmon Gap, and 124% of normal for Rio Grande Village. Castolon had 88% of normal annual precipitation. All five stations had higher than normal rainfall in October and December, while rainfall totals were substantially below normal at all stations in November, February, and March. Monthly precipitation totals for April through September were more variable from station to station. Mean monthly maximum air temperatures were below normal in the fall months, with Panther Junction as much as 7.5°F below normal in October. Monthly temperatures from January through July were more variable. Temperatures in August and September were warmer than normal at every station, up to +9.4°F at Rio Grande Village and +8.7°F at Chisos Basin in July. The reconnaissance drought index values indicate generally wetter conditions (based on precipitation and evaporative demand) at Chisos Basin since WY2016 and at Panther Junction and Persimmon Gap since WY2015, except for WY2017. This report presents the manual and automatic groundwater monitoring results at nine wells. Five wells had their highest water level in or just before WY2019: Panther Junction #10 peaked at 99.94 ft below ground surface (bgs) in September 2018, Contractor’s Well peaked at 31.43 ft bgs in November 2018, T-3 peaked at 65.39 ft bgs in December 2018, K-Bar #6 Observation Well peaked at 77.78 ft bgs in February 2019, and K-Bar #7 Observation Well peaked at 43.18 ft bgs in February 2019. This was likely in response to above normal rainfall in the later summer and fall 2018. The other monitoring wells did not directly track within-season precipitation. The last measurement at Gallery Well in WY2019 was 18.60 ft bgs. Gallery Well is located 120 feet from the river and closely tracked the Rio Grande stage, generally increasing in late summer or early fall following higher flow events. Water levels in Gambusia Well were consistently very shallow, though the manual well measurement collected in April was 4.25 ft bgs—relatively high for the monitoring record—and occurred outside the normal peak period of later summer and early fall. The last manual measurement taken at TH-10 in WY2019 was 34.80 ft bgs, only 0.45 ft higher than the earliest measurement in 1967, consistent with the lack of directional change in groundwater at this location, and apparently decoupled from within-season precipitation patterns. The last water level reading in WY2019 at Oak Springs #1 was 59.91 ft bgs, indicating an overall decrease of 26.08 ft since the well was dug in 1989. The Southwest Network Collaboration (SWNC) collects data on sentinel springs annually in the late winter and early spring following the network springs monitoring protocol. In WY2019, 18 sentinel site springs were visited at Big Bend NP (February 21, 2019–March 09, 2019). Most springs had relatively few indications of natural and anthropogenic disturbances. Natural disturbances included recent flooding, drying, and wildlife use. Anthropogenic disturbances included flow modifications (e.g., springboxes), hiking trails, and contemporary human use. Crews observed one to seven facultative/obligate wetland plant...
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Dainty, Anton M. Coda Observed a NORSAR and NORESS. Fort Belvoir, VA: Defense Technical Information Center, agosto de 1985. http://dx.doi.org/10.21236/ada166454.
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Stefanoni, Pablo. En Venezuela, "Todo está muy normal". Fundación Carolina, octubre de 2022. http://dx.doi.org/10.33960/ac_17.2022.
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La situación venezolana se ha venido transformando en el plano interno y externo. Se observa una consolidación de Nicolás Maduro en el poder, en medio de un esfuerzo del gobierno bolivariano por mostrar que el país salió del pozo, pese a las sanciones económicas. La coyuntura política latinoamericana y la invasión rusa de Ucrania han cambiado también el contexto geopolítico internacional. Con negociaciones en varios planos entre Caracas y Washington, la oposición —al igual que el debilitado “gobierno encargado”— busca reposicionarse en el nuevo escenario —y reorganizarse internamente— con vistas a las presidenciales de 2024.
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Raymond, Kara, Laura Palacios, Cheryl McIntyre y Evan Gwilliam. Status of climate and water resources at Chiricahua National Monument, Coronado National Memorial, and Fort Bowie National Historic Site: Water year 2019. National Park Service, mayo de 2022. http://dx.doi.org/10.36967/nrr-2293370.
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Climate and hydrology are major drivers of ecosystems. They dramatically shape ecosystem structure and function, particularly in arid and semi-arid ecosystems. Understanding changes in climate, groundwater, and water quality and quantity is central to assessing the condition of park biota and key cultural resources. The Sonoran Desert Network collects data on climate, groundwater, and surface water at 11 National Park Service units in southern Arizona and New Mexico. This report provides an integrated look at climate, groundwater, and springs conditions at Chiricahua National Monument (NM), Coronado National Memorial (NMem), and Fort Bowie National Historic Site (NHS) during water year (WY) 2019 (October 2018–September 2019). Overall annual precipitation at Chiricahua NM and Coronado NMem in WY2019 was approximately the same as the normals for 1981–2010. (The weather station at Fort Bowie NHS had missing values on 275 days, so data were not presented for that park.) Fall and winter rains were greater than normal. The monsoon season was generally weaker than normal, but storm events related to Hurricane Lorena led to increased late-season rain in September. Mean monthly maximum temperatures were generally cooler than normal at Chiricahua, whereas mean monthly minimum temperatures were warmer than normal. Temperatures at Coronado were more variable relative to normal. The reconnaissance drought index (RDI) indicated that Chiricahua NM was slightly wetter than normal. (The WY2019 RDI could not be calculated for Coronado NMem due to missing data.) The five-year moving mean of annual precipitation showed both park units were experiencing a minor multi-year precipitation deficit relative to the 39-year average. Mean groundwater levels in WY2019 increased at Fort Bowie NHS, and at two of three wells monitored at Chiricahua NM, compared to WY2018. Levels in the third well at Chiricahua slightly decreased. By contrast, water levels declined in five of six wells at Coronado NMem over the same period, with the sixth well showing a slight increase over WY2018. Over the monitoring record (2007–present), groundwater levels at Chiricahua have been fairly stable, with seasonal variability likely caused by transpiration losses and recharge from runoff events in Bonita Creek. At Fort Bowie’s WSW-2, mean groundwater level was also relatively stable from 2004 to 2019, excluding temporary drops due to routine pumping. At Coronado, four of the six wells demonstrated increases (+0.30 to 11.65 ft) in water level compared to the earliest available measurements. Only WSW-2 and Baumkirchner #3 have shown net declines (-17.31 and -3.80 feet, respectively) at that park. Springs were monitored at nine sites in WY2019 (four sites at Chiricahua NM; three at Coronado NMem, and two at Fort Bowie NHS). Most springs had relatively few indications of anthropogenic or natural disturbance. Anthropogenic disturbance included modifications to flow, such as dams, berms, or spring boxes. Examples of natural disturbance included game trails, scat, or evidence of flooding. Crews observed 0–6 facultative/obligate wetland plant taxa and 0–3 invasive non-native species at each spring. Across the springs, crews observed six non-native plant species: common mullein (Verbascum thapsus), spiny sowthistle (Sonchus asper), common sowthistle (Sonchus oleraceus), Lehmann lovegrass (Eragrostis lehmanniana), rabbitsfoot grass (Polypogon monspeliensis), and red brome (Bromus rubens). Baseline data on water quality and water chemistry were collected at all nine sites. It is likely that that all nine springs had surface water for at least some part of WY2019, though temperature sensors failed at two sites. The seven sites with continuous sensor data had water present for most of the year. Discharge was measured at eight sites and ranged from < 1 L/minute to 16.5 L/minute.
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Fallesen, Peter, Lars Dommermuth, Julia Hellstrand, Emil Simonsen, Lisbeth Trille Gylling Loft y Laust H. Mortensen. Research note: comparing ideal family size with observed and forecasted completed cohort fertility in Denmark and Norway. Rostock: Max Planck Institute for Demographic Research, noviembre de 2022. http://dx.doi.org/10.4054/mpidr-wp-2022-031.
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Frydman, Roman y Joshua Stillwagon. Market Participants Neither Commit Predictable Errors nor Conform to REH: Evidence from Survey Data of Inflation Forecasts. Institute for New Economic Thinking Working Paper Series, septiembre de 2021. http://dx.doi.org/10.36687/inetwp163.
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We develop a novel characterization of participants’ forecasts with a mixture of normal variables arising from a Markov component. Using this characterization, we formulate five behavioral specifications, including four implied by the diagnostic expectations approach, as well as three implied by REH, and derive several new predictions for Coibion and Gorodnichenko.s regression of forecast errors on forecast revisions. Predictions of all eight specifications are inconsistent with the observed instability of individual CG regressions’ coefficients, based on inflation forecasts from 24 professionals. Our findings suggest how to build on key insights of the REH and behavioral approaches in specifying individuals’ forecasts.
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Hendricks, Stefanie, Iryna Dykun, Bastian Balcer, Matthias Totzeck, Tienush Rassaf y Amir A. Mahabadi. Higher BNP/NT-pro BNP levels stratify prognosis equally well in patients with and without heart failure – a meta-analysis with more than 89,000 patients. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, abril de 2022. http://dx.doi.org/10.37766/inplasy2022.4.0175.
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Review question / Objective: We performed a meta-analysis to investigate, whether the value of BNP/NT-proBNP as predictors of long-term prognosis differentiates in cohorts with and without heart failure. Condition being studied: The standardised cut-off levels for BNP and NT-proBNP that are currently used in clinical practice are based on the stratification of patients with heart failure. In patients without heart failure, however, relatively lower values are observed. This leads to the assumption that the prognosis for patients with BNP/NT-proBNP levels at the upper limit of the normal range might be worse than the prognosis for patients with BNP/NT-proBNP levels lower in the range, even if both are determined to be within the normal boundaries. However, a specific cut-off level of BNP/NT-proBNP for the prediction of prognosis in patients without heart failure has not yet been determined. Therefore, we performed a meta-analysis of existing studies investigating the value of BNP/NT-proBNP as a predictor of long-term prognosis in patients with heart failure and the general population.
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Carpita, Nicholas C., Ruth Ben-Arie y Amnon Lers. Pectin Cross-Linking Dynamics and Wall Softening during Fruit Ripening. United States Department of Agriculture, julio de 2002. http://dx.doi.org/10.32747/2002.7585197.bard.
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Our study was designed to elucidate the chemical determinants of pectin cross-linking in developing fruits of apple and peach and to evaluate the role of breakage cross-linkages in swelling, softening, and cell separation during the ripening. Peaches cell walls soften and swell considerably during the ripening, whereas apples fruit cells maintain wall firmness but cells separate during late stages of ripening. We used a "double-reduction" technique to show that levels of non-methyl esters of polyuronic acid molecules were constant during the development and ripening and decreased only in overripe fruit. In peach, methyl and non-methyl esters increased during the development and decreased markedly during the ripening. Non-methyl ester linkages in both fruit decreased accompanied fruit softening. The identity of the second component of the linkage and its definitive role in the fruit softening remain elusive. In preliminary examination of isolated apples cell walls, we found that phenolic compounds accumulate early in wall development but decrease markedly during ripening. Quantitative texture analysis was used to correlate with changes to wall chemistry from the fresh-picked ripe stage to the stage during storage when the cell separation occurs. Cell wall composition is similar in all cultivars, with arabinose as the principal neutral sugar. Extensive de-branching of these highly branched arabinans pre-stages softening and cell-cell separation during over-ripening of apple. The longer 5-arabinans remain attached to the major pectic polymer rhamnogalacturonan I (RG I) backbone. The degree of RG I branching, as judged from the ratios of 2-Rha:2,4-Rha, also decreases, specially after an extensive arabinan de-branching. Loss of the 4-Rham linkages correlated strongly with the softening of the fruit. Loss of the monomer or polymer linked to the RG I produce directly or indirectly the softening of the fruit. This result will help to understand the fruit softening and to have better control of the textural changes in fruit during the ripening and especially during the storage. 'Wooliness', an undesirable mealy texture that is induced during chilling of some peach cultivars, greatly reduces the fruit storage possibilities. In order to examine the hypothesis that the basis for this disorder is related to abnormality in the cell wall softening process we have carried out a comparative analysis using the resistant cultivar, Sunsnow, and a sensitive one, Hermosa. We investigated the activity of several pectin- and glycan-modifying enzymes and the expression of their genes during ripening, chilling, and subsequent shelf-life. The changes in carbohydrate status and in methyl vs. non-methyl uronate ester levels in the walls of these cultivars were examined as well to provide a basis for comparison of the relevant gene expression that may impact appearance of the wooly character. The activities of the specific polygalacturonase (PGase) and a CMC-cellulase activities are significantly elevated in walls of peaches that have become wooly. Cellulase activities correlated well with increased level of the transcript, but differential expression of PGase did not correspond with the observed pattern of mRNA accumulation. When expression of ethylene biosynthesis related genes was followed no significant differences in ACC synthase gene expression was observed in the wooly fruit while the normal activation of the ACC oxidase was partially repressed in the Hermosa wooly fruits. Normal ripening-related loss of the uronic acid-rich polymers was stalled in the wooly Hermosa inconsistent with the observed elevation in a specific PGase activity but consistent with PG gene expression. In general, analysis of the level of total esterification, degree of methyl esterification and level of non-methyl esters did not reveal any major alterations between the different fruit varieties or between normal and abnormal ripening. Some decrease in the level of uronic acids methyl esterification was observed for both Hermosa and Sunsnow undergoing ripening following storage at low temperature but not in fruits ripening after harvest. Our results support a role for imbalanced cell wall degradation as a basis for the chilling disorder. While these results do not support a role for the imbalance between PG and pectin methyl esterase (PME) activities as the basis for the disorder they suggest a possible role for imbalance between cellulose and other cell wall polymer degradation during the softening process.
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Jettestuen, Espen, Olav Aursjø, Jan Ludvig Vinningland, Aksel Hiorth y Arild Lohne. Smart Water flooding: Part 2: Important input parameters for modeling and upscaling workflow. University of Stavanger, noviembre de 2021. http://dx.doi.org/10.31265/usps.200.
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This document presents some guidelines on how to conduct numerical investigations of the physicochemical effects of Smart Water flooding on different length scales. The National IOR Centre of Norway (NIORC) has developed several simulation tools. The objective of this report is to describe how three NIORC-developed simulation tools BADChIMP, IORCoreSim, and IORSim, can be used to investigate Smart Water effects on different length scales. We present which input parameters are needed by the simulation tools, and we discuss which processes these tools are suited to study. When working with different length scales, one of the challenges is how to upscale results obtained from smaller scales, i.e., pore and core scale experiments or simulations, to the field scale. Here, three relevant questions are: 1) how far do the Smart Water effects propagate into a reservoir? 2) What is the effect of reservoir temperature on Smart Water behavior? 3) How is the oil release, observed on core scale, related to the oil production from a field? This document targets research scientists planning to perform either pore scale simulations, core scale simulations, or field scale simulations for Smart Water studies. The technical level of the document is targeting an industry engineer.
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Bosch, Mariano, Suzanne Duryea, Stephanie González y María Teresa Silva Porto. Intervención conductual para mejorar el cumplimiento de la cuota de empleo de personas con discapacidad en Perú. Inter-American Development Bank, abril de 2021. http://dx.doi.org/10.18235/0003148.
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Existe evidencia empírica que los recordatorios, mensajes disuasorios y las normas sociales y morales afectan el comportamiento de los individuos respecto al cumplimiento de sus obligaciones tributarias. Este estudio analiza el cumplimiento de la cuota de empleo de personas con discapacidad en Perú, a través de un experimento aleatorio en el cual la agencia de inspección laboral peruana (SUNAFIL) envió 1000 cartas a empresas formales de más de 50 trabajadores, indicándoles la obligatoriedad de cumplir con la cuota de empleo de trabajadores con discapacidad. Se seleccionaron aleatoriamente a 500 empresas para enviarles la carta con mensaje punitivo y a otras 500 empresas para enviarles la carta con mensaje de compromiso social. Un año después del envío de las cartas no se observa un cambio de comportamiento con respecto al cumplimiento de la cuota de discapacidad, sin embargo, las cartas tuvieron un efecto positivo y estadísticamente significativo en el porcentaje de empresas que contrataron al menos una hora de trabajadores con discapacidad (1,5 puntos porcentuales). El mayor impacto se encontró entre las empresas que recibieron la carta con mensaje punitivo (1,8 puntos porcentuales), siendo el impacto estadísticamente significativo. En el caso de las cartas con mensaje de compromiso el impacto no fue estadísticamente significativo (1,1 puntos porcentuales). Esta evidencia sugiere que existe aún un margen de mejora del cumplimiento de las regulaciones laborales, ya sea a través de una fiscalización más proactiva y/o herramientas conductuales complementarias como los recordatorios.