Relevant bibliographies by topics / Contrôle top-down

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Academic literature on the topic 'Contrôle top-down'

Author: Grafiati
Published: 4 June 2021
Last updated: 3 February 2022

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Journal articles on the topic "Contrôle top-down"

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KIMURA, Motohiro, and Yuji TAKEDA. "Top-down Control over the Processing of Task-irrelevant Rule Violation:Evidence from Visual Mismatch Negativity." Japanese Journal of Physiological Psychology and Psychophysiology 33, no. 1 (2015): 19–31. http://dx.doi.org/10.5674/jjppp.1504si.

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Yoshida, T., S. Ban, T. Takenouchi, et al. "Top-down control of population dynamics of the dominant rotifers in two mesotrophic lakes in Hokkaido, Japan." Fundamental and Applied Limnology 148, no. 4 (2000): 481–98. http://dx.doi.org/10.1127/archiv-hydrobiol/148/2000/481.

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Kwak, Nam-Su, Choul-Jun Choi, and Jeong-Gi Lee. "A Study on the Shape Control of Multiple Layers for PES Nanofiber Using Electrospinning Method of Top-down Spinning." International Journal of Materials Science and Engineering 7, no. 3 (2019): 81–88. http://dx.doi.org/10.17706/ijmse.2019.7.3.81-88.

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Chernyak, D. A., and L. W. Stark. "Top-down guided eye movements." IEEE Transactions on Systems, Man and Cybernetics, Part B (Cybernetics) 31, no. 4 (2001): 514–22. http://dx.doi.org/10.1109/3477.938257.

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Zhu, Jun, Yuanyuan Qiu, Rui Zhang, Jun Huang, and Wenjun Zhang. "Top-Down Saliency Detection via Contextual Pooling." Journal of Signal Processing Systems 74, no. 1 (2013): 33–46. http://dx.doi.org/10.1007/s11265-013-0768-9.

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le Roux, J. D., S. Skogestad, and I. K. Craig. "Plant-wide control of grinding mill circuits: Top-down analysis." IFAC-PapersOnLine 49, no. 20 (2016): 72–77. http://dx.doi.org/10.1016/j.ifacol.2016.10.099.

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Ullman, Jeffrey D., and Allen Van Gelder. "Efficient tests for top-down termination of logical rules." Journal of the ACM 35, no. 2 (1988): 345–73. http://dx.doi.org/10.1145/42282.42285.

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Zerlin, Benno, Michel T. Ivrlač, Wolfgang Utschick, and Josef A. Nossek. "Joint optimization of radio parameters—A top–down approach." Signal Processing 86, no. 8 (2006): 1773–91. http://dx.doi.org/10.1016/j.sigpro.2005.09.030.

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Madhav, Manu S., and Noah J. Cowan. "The Synergy Between Neuroscience and Control Theory: The Nervous System as Inspiration for Hard Control Challenges." Annual Review of Control, Robotics, and Autonomous Systems 3, no. 1 (2020): 243–67. http://dx.doi.org/10.1146/annurev-control-060117-104856.

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Here, we review the role of control theory in modeling neural control systems through a top-down analysis approach. Specifically, we examine the role of the brain and central nervous system as the controller in the organism, connected to but isolated from the rest of the animal through insulated interfaces. Though biological and engineering control systems operate on similar principles, they differ in several critical features, which makes drawing inspiration from biology for engineering controllers challenging but worthwhile. We also outline a procedure that the control theorist can use to draw inspiration from the biological controller: starting from the intact, behaving animal; designing experiments to deconstruct and model hierarchies of feedback; modifying feedback topologies; perturbing inputs and plant dynamics; using the resultant outputs to perform system identification; and tuning and validating the resultant control-theoretic model using specially engineered robophysical models.
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Rokach, L., and O. Maimon. "Top-Down Induction of Decision Trees Classifiers—A Survey." IEEE Transactions on Systems, Man and Cybernetics, Part C (Applications and Reviews) 35, no. 4 (2005): 476–87. http://dx.doi.org/10.1109/tsmcc.2004.843247.

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Dissertations / Theses on the topic "Contrôle top-down"

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Lévesque, Johann. "Évaluation de la qualité des données géospatiales : approche top-down et gestion de la métaqualité." Thesis, Université Laval, 2007. http://www.theses.ulaval.ca/2007/24759/24759.pdf.

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Depuis l’avènement du numérique, la demande de données par les utilisateurs des systèmes d’information géographique (SIG) ne fait qu’augmenter. Les organismes utilisateurs se retrouvent souvent devant plusieurs sources de données géographiques potentielles et ils doivent alors évaluer la qualité de chaque source en fonction de leurs besoins. Pour ce faire, ces organismes pourraient faire appel à un expert en qualité qui pourrait les aider à déterminer s’il y a adéquation (i.e. qualité externe) entre les données et leurs besoins. Pour utiliser le système MUM, l’expert en qualité doit recueillir de l’information sur les jeux de données. Dans le domaine de la géomatique, cette information se retrouve généralement sous la forme de métadonnées émises par les producteurs de données. Le système MUM, développé par Devillers et al. [2004b], a été conçu initialement en fonction d’une approche bottom-up, où on utilise des métadonnées fines pour extraire des indicateurs globaux de qualité, à l’aide d’opérateurs d’agrégation typiques des outils SOLAP. Il s’agit là d’une solution qui permet de faciliter l’analyse de la qualité, particulièrement dans des contextes de données hétérogènes. Par contre, comme le mentionnent les concepteurs de MUM, le manque de métadonnées fines est un obstacle à l’utilisation du système MUM dans sa forme actuelle. L’objectif de la présente recherche a donc été d’élaborer une méthode de génération des métadonnées dite top-down. Cette méthode permet de générer, lorsque possible, les métadonnées fines (au niveau des occurrences, voire des primitives géométriques) d’un jeu de données à l’aide des métadonnées grossières et des opinions d’experts touchant un ensemble d’occurrences. Cette méthodologie amène l’expert en qualité à utiliser dans certains cas des sources de données différentes. Ceci soulève alors un problème concernant l’hétérogénéité de la fiabilité des sources utilisées pour évaluer la qualité externe. Le concept de métaqualité a été introduit pour répondre à ce problème d’hétérogénéité. Il permet en effet de quantifier le risque lié à l’imperfection de l’information contenue dans les indicateurs de qualité. L’enrichissement du système MUM a donc été réalisé grâce à la conception du modèle E-QIMM (Extented Quality Information Management Model) qui est une extension du modèle QIMM de Devillers [2004] et qui permet d’intégrer la dimension « Métaqualité » dans le processus d’évaluation de la qualité.
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Wigley, Benjamin Joseph. "Savanna woody plant community and trait responses to bottom-up and top-down controls, with a specific focus on the role of mammalian herbivory." Thesis, Lyon 1, 2013. http://www.theses.fr/2013LYO10133/document.

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Les savanes sont des écosystèmes complexes pilotées par plusieurs mécanismes ascendant (ex: les nutriments du sol ou pluviométrie) ou descendant (ex: feu ou herbivorie), mais l'importance relative de ces mécanismes reste largement débattue. En particulier, le rôle des herbivores brouteurs (browsers) reste mal compris en tant que source de perturbation, et donc de force de pression descendante influant sur la dynamique des savanes. Dans cette étude, deux approches ont été développées pour aborder le rôle des perturbations dans la dynamique des savanes. Dans un première partie, j'ai utilisé une approche comparative inter-site pour explorer les réponses des communautés de plantes, et des principaux traits de ces plantes associés aux feuilles, branches, architecture et défense, aux variations de quatre facteurs : les nutriments dans le sol, la pluviométrie, la pression d'herbivorie et l'intensité du feu. Seize sites de savane, en Afrique du Sud et au Zimbabwe, ont été sélectionnés sur des gradients de chacun de ces facteurs. Les espèces ligneuses dominantes (&gt;80 % de la biomasse) sur chaque site ont été identifiées et échantillonnées, afin de mesurer les traits des feuilles et des branches associés à l'appétence, architecture, ainsi qu'aux défenses physiques et chimiques de ces plantes. Des mesures ont également été faites pour estimer les effets des meso-brouteurs et mega-brouteurs. Des transects ont permis d'estimer la fréquence et l'intensité du feu sur chaque site, et l'effet sur les plantes. En préambule à l'analyse, et devant le manque de protocole standard pour estimer la fertilité des sols dans la littérature écologique, je propose une méthode et un échantillonnage afin de définir de manière robuste la fertilité des sols sur chaque site. Dans cette partie inter-site, huit traits principaux ont été comparés sur le gradient de qualité de sol et de pluviométrie, et bien que quelques relations statistiques existent entre les traits des feuilles, le sol et la pluviométrie, ces relations sont très faibles comparées à celle trouvées dans les méta analyses inter-biomes publiées dans la littérature. Cependant, ces approches interbiome sont dominées par des sites tempérés qui ont des niveaux de perturbations bien inférieurs à ceux des savanes africaines. L'évaluation des effets des meso-brouteurs et mega-brouteurs le long des gradients de sol et de pluviométrie sur vingt traits associés aux défenses structurelles et chimiques des plantes montre que les défenses structurelles sont plus corrélées aux caractéristiques du sol que les défenses chimiques, mais que seules les défenses structurelles sont fortement corrélées à l'impact par les brouteurs. Le niveau d'utilisation des plantes par les mesobrouteurs apparaît plus prévisible en fonction des traits des plantes que celui par les mégabrouteurs. Dans une deuxième partie présentent des résultats de deux études basées sur des expériences d'exclos. Dans le parc national de Kruger, la composition de la communauté, l'abondance et la démographie des ligneux dominants ont été estimées à l'intérieur et à l'extérieur de trois exclos de 40 ans, et les brouteurs apparaissent comme ayant un impact significatif sur la distribution, la densité et la structure des populations des espèces arbustives et arborées ayant des traits préférés : forte concentration en azote foliaire et faible teneur en défenses chimiques. L'interaction entre les effets des brouteurs et du feu semble aussi affecter le recrutement des juvéniles ligneux dans les grandes classes de taille. Dans le parc de Hluhluwe-iMfolozi, cinq exclos ont été utilisé pour tester l'effet des brouteurs sur l'architecture, la croissance, les défenses chimiques et structurelles des jeunes individus de sept espèces d'acacia. Des différences nettes apparaissent entre les espèces d'acacia de savane semi-aride et plus humide dans les traits associés à l'appétence, l'architecture et les défenses … [etc]<br>Savannas are complex ecosystems affected by several bottom-up (e.g. soil nutrient availability and rainfall) and top-down (e.g. fire and herbivory) drivers. However, the relative importance of bottom-up vs. top-down drivers in influencing savanna dynamics is still widely debated. Within the top-down (disturbance) category of drivers, the role of mammal browsers in particular in driving savanna functioning is still not well understood. Two approaches were adopted to determine the role of disturbance in savannas. Firstly, by using a comparative approach, I attempted to address the so-called ‘savanna problem’ by investigating how savanna woody plant community compositions and key plant traits relating to the leaves, stems, architecture, and defence are influenced by soil nutrient status, rainfall, fire and browsing. Sixteen sites were selected along gradients of these four drivers from savanna parks throughout South Africa and Zimbabwe. The dominant woody species (species that accounted for &gt;80% of standing biomass) at each site were identified and sampled for the key leaf and stem traits relating to plant functioning, palatability, architecture, physical and chemical defences. Measurements were undertaken for each species in order to determine both meso-browser and mega browser impact. Transects were undertaken in order to determine the relative abundance and the effects of fire on each species at each site. Due to the current lack of standardized soil sampling protocols in the ecological literature, and uncertainty around the definition of what denotes a fertile or infertile soil, I propose a number of standardized protocols and sampled according to these established protocols in order to accurately determine the soil nutrient status at each site. Following this, the relationships between climatic variables and soil nutrients with both species means and community weighted means for eight key leaf traits were explored. Although some significant relationships were found between savanna leaf traits of woody plants, climate, soil nutrients and their interactions, these tended to be weaker than those found in meta-analyses. These broad-scale studies usually include sites from many biome types, many of which are from temperate regions where inherent levels of disturbance are typically much lower than in African savannas. The high levels of disturbance typically found in African savannas are thought to partially account for the high within site variability found in leaf traits and the weak relationships found between leaf traits, soil nutrients and rainfall. To assess the importance of resources vs. disturbance in savannas functioning, the effects of soil nutrients, rainfall, fire and both meso-browser and mega-browser impact on twenty savanna woody plant traits relating to plant palatability, chemical and structural defences were explored. Structural defences were found to be more strongly correlated with soil characteristics than chemical defences, while browser impact was found to be strongly correlated with structural defences but not with chemical defences. Actual browser utilisation tended to be more predictable for meso-browsers than mega-browsers. Secondly using an experimental approach, two sets of herbivore exclosures were utilized to directly test how mammal browsers influenced woody species distributions, abundance, population structure and plant traits relating to palatability and defence. The effects of three longterm herbivore exclosures in the Kruger National Park on savanna woody plant community compositions, population demographics and densities were determined. Browsers were found to have significant impacts on species distributions, densities and population structures by actively selecting for species with favourable traits, particularly higher leaf N. An interaction between browsers and fire which limited the recruitment of seedlings and saplings into larger size classes was also demonstrated… [etc]
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Foulquier, Arnaud. "Écologie fonctionnelle dans les nappes phréatiques : liens entre flux de matière organique, activité et diversité biologiques." Phd thesis, Université Claude Bernard - Lyon I, 2009. http://tel.archives-ouvertes.fr/tel-00587833.

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Les réseaux trophiques jouent un rôle primordial dans la régulation des flux de matière et d'énergie au sein des écosystèmes. Dans le cadre des pratiques de recharge artificielle des aquifères, les biocénoses souterraines sont pleinement sollicitées et leur capacité à dégrader les flux de matière organique de surface conditionne le maintien de la qualité des eaux souterraines. L'objectif de ce travail est de déterminer l'influence d'une augmentation des flux de carbone organique dissous sur l'intensité des interactions trophiques entre les communautés microbiennes et les assemblages d'invertébrés au toit des nappes phréatiques rechargées artificiellement avec des eaux de ruissellement pluvial. A travers une approche expérimentale de terrain et de laboratoire, ce travail permet d'évaluer l'intensité des relations existant entre les flux de carbone organique dissous, les conditions environnementales, l'activité et la diversité de communautés microbiennes et l'abondance des communautés d'invertébrés.
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Quevreux, Pierre. "Conséquences des interactions entre voies vertes et brunes sur la stabilité des réseaux trophiques." Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCC142/document.

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Cette thèse a pour but de comprendre les implications des relations entre réseau trophique vert et réseau trophique brun sur la stabilité et le fonctionnement des réseaux trophiques. Les interactions entre ces deux réseaux, respectivement fondés sur la photosynthèse et la consommation de la matière organique morte, sont essentielles au fonctionnement des écosystèmes : l'un produit de la matière organique à partir de nutriments minéraux et l'autre recycle les nutriments contenus dans la matière organique morte. Cette question est abordée à l'aide de deux modèles théoriques et d'une étude expérimentale. Mon premier modèle montre que la boucle de rétroaction induite par le recyclage des nutriments dans un réseau trophique exclusivement vert a un effet stabilisant sur les dynamiques d'une chaîne trophique et un effet enrichissement à cause de la remise à disposition pour les producteurs primaires des nutriments excrétés par l'ensemble des organismes du réseau trophique. Cependant seul l'effet enrichissement, qui est déstabilisant, persiste dans un modèle de réseau trophique. Mon second modèle intègre le réseau brun de manière explicite et montre que ce réseau est davantage déstabilisé que le réseau vert lorsque la disponibilité en nutriments augmente. Cette effet est amplifié si la majeure partie de l'excrétion se fait sous forme de détritus qui déstabilisent le réseau brun par un effet d'enrichissement. Ce modèle montre également que la survie des consommateurs est améliorée lorsqu'ils peuvent consommer des proies provenant des deux réseaux. Mon expérience en mésocosmes aquatiques a permis d'étudier les effets en cascades entre réseaux vert et brun via une filtration de la lumière (manipulation directe du réseau vert), l'ajout de carbone organique dissous (manipulation directe du réseau brun) et l'ajout de poissons (manipulation de la structure du réseau trophique). Nous n'avons pas observé d'effets en cascade du réseau vert sur le réseau brun et inversement, notamment à cause d'un ajout probablement trop faible de carbone dissout. Les poissons ont eux eu un fort effet sur les deux réseaux avec des effets positifs sur le phytoplancton lorsque la lumière est réduite à cause de la diminution de la limitation par les nutriments grâce à l'excrétion des poissons, une augmentation de la concentration en carbone organique dissout et une modification du profil métabolique de la communauté bactérienne benthique. Un modèle annexe montre quant à lui que la plasticité du métabolisme chez les organismes, c'est-à-dire leur capacité à réduire ou à augmenter leur métabolisme en fonction de la disponibilité en ressources afin de maximiser leur bilan énergétique permet de stabiliser les dynamiques d'une chaine trophique en diminuant la variabilité temporelle des biomasses des espèces. Dans un réseau trophique, cette stabilisation se traduit par une augmentation de la persistance des espèces. Cette thèse a permis de mieux relier l'écologie des communautés à l'écologie fonctionnelle, améliorant ainsi notre compréhension des conséquences de grands processus écosystémiques comme le recyclage des nutriments sur la stabilité des réseaux trophiques et des effets de la structure de ces réseaux sur le fonctionnement des écosystèmes<br>The aim of this thesis is to understand the implications of the relationships between green and brown food webs on the stability and functioning of food webs. The interactions between these two food webs, based respectively on photosynthesis and the consumption of dead organic matter, are essential for the functioning of ecosystems: one produces organic matter from mineral nutrients and the other one recycles the nutrients contained in dead organic matter. I address this by using two theoretical models and an experimental study. My first model shows that the feedback loop induced by nutrient cycling in an exclusively green food web has a stabilising effect on species dynamics in a food chain and an enrichment effect due to the excretion of nutrients that are available again for primary producers. However, only the enrichment effect, which is destabilising, persists in a food web model. My second model integrates a true brown food web and shows that this food web is more destabilised than the green food web when nutrient availability increases. This effect is amplified if most of nutrients are excreted as detritus that destabilises the brown food web through an enrichment effect. This model also shows that consumer survival is improved when they can consume prey from both green and brown food webs. My experiment in aquatic mesocosms enabled me to study the cascading effects between green and brown food webs thanks to light filtration (direct manipulation of the green food web), the addition of dissolved organic carbon (direct manipulation of the brown food web) and the addition of fish (manipulation of food web structure). We did not observe any cascading effects of the green food web on the brown food web and vice versa, probably because of a too low addition of dissolved carbon. The fish had a strong effect on both green and brown food webs with positive effects on phytoplankton when light is filtered because of the decreased nutrient limitation thanks to fish excretion, an increased concentration of dissolved organic carbon and a change in the metabolic profile of the benthic bacterial community. An additional model shows that the plasticity of metabolic rate, that is the ability of organisms to increase or decrease their metabolic rate depending on resource availability in order to optimise their energy budget, stabilises species dynamics in a food chain model by decreasing biomass time variability. Such a stabilising effect results in increase of species persistence in a complex food web model. This thesis is an additional step to better link community ecology to functional ecology, thus improving our understanding of the consequences on food web stability of major ecosystem processes such as the nutrient cycling and the effects of food web structure on ecosystem functioning
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Skogsholm, Lauren. "Distractibility, Impulsivity, and Activation of Top-down Control Resources." Thesis, Boston College, 2011. http://hdl.handle.net/2345/1977.

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Thesis advisor: Elizabeth Kensinger<br>Thesis advisor: Katherine Mickley Steinmetz<br>Distractibility and impulsivity have long been thought of as two separate psychological processes; however, there is currently evidence that suggests otherwise. The aim of this study was to gain a better understanding on the behavioral level of the interaction between these two traits. I proposed a model in which some individuals have a higher than average threshold for activation of the top-down cognitive control resources that are important for directing and maintaining attention as well as for regulating impulsive behaviors. To test the strength of this model I used an experimental paradigm that combined two different types of tasks—a spatial working memory task and a delay discounting of a primary reward (juice) task. Participants were administered the Conners’ Adult ADHD Rating Scale in order to be classified in terms of their trait distractibility and trait impulsivity subscale scores. The results suggest that there is indeed an association between the traits of distractibility and impulsivity, and that they may be linked by a common mechanism involving a variable threshold of activation of top-down control resources to regulate these behaviors<br>Thesis (BS) — Boston College, 2011<br>Submitted to: Boston College. College of Arts and Sciences<br>Discipline: College Honors Program<br>Discipline: Psychology
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Burkholder, Derek A. "Top Down Control in a Relatively Pristine Seagrass Ecosystem." FIU Digital Commons, 2012. http://digitalcommons.fiu.edu/etd/799.

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The loss of large-bodied herbivores and/or top predators has been associated with large-scale changes in terrestrial, freshwater, and marine ecosystems around the world. Understanding the consequences of these declines has been hampered by a lack of studies in relatively pristine systems. To fill this gap, I investigated the dynamics of the relatively pristine seagrass ecosystem of Shark Bay, Australia. I began by examining the seagrass species distributions, stoichiometry, and patterns of nutrient limitation across the whole of Shark Bay. Large areas were N-limited, P-limited, or limited by factors other than nutrients. Phosphorus-limitation was centered in areas of restricted water exchange with the ocean. Nutrient content of seagrasses varied seasonally, but the strength of seasonal responses were species-specific. Using a cafeteria-style experiment, I found that fast-growing seagrass species, which had higher nutrient content experienced higher rates of herbivory than slow-growing species that are dominant in the bay but have low nutrient content. Although removal rates correlated well with nutrient content at a broad scale, within fast-growing species removal rates were not closely tied to N or P content. Using a combination of stable isotope analysis and animal borne video, I found that green turtles (Chelonia mydas) – one of the most abundant large-bodied herbivores in Shark Bay – appear to assimilate little energy from seagrasses at the population level. There was, however, evidence of individual specialization in turtle diets with some individuals foraging largely on seagrasses and others feeding primarily on macroalgae and gelatinous macroplankton. Finally, I used exclusion cages, to examine whether predation-sensitive habitat shifts by megagrazers (green turtles, dugongs) transmitted a behavior-mediated trophic cascade (BMTC) between sharks and seagrasses. In general, data were consistent with predictions of a behavior-mediated trophic cascade. Megaherbivore impacts on seagrasses were large only in the microhabitat where megaherbivores congregate to reduce predation risk. My study highlights the importance of large herbivores in structuring seagrass communities and, more generally, suggests that roving top predators likely are important in structuring communities - and possibly ecosystems - through non-consumptive pathways.
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Best, Maisy Jane. "Top-down and bottom-up influences on response inhibition." Thesis, University of Exeter, 2016. http://hdl.handle.net/10871/24650.

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Following exposure to consistent stimulus–stop mappings, response inhibition can become automatised with practice. What is learned is less clear, even though this has important theoretical and practical implications. The main contribution of this thesis is to investigate how stimulus-stop associations are acquired and the conditions under which they influence behaviour. To this end, this thesis addressed several outstanding issues concerning the associative architecture of stop learning, the role of expectancies, and the specificity of learning in inhibition tasks. Experiments 1-4 provide evidence that participants can acquire direct associations between specific stimuli and the stop goal without mediation via a single representation of the stop signal. However, these experiments also suggest that the influence of stimulus-stop associations on behaviour depends on top-down attentional settings: if participants begin to ignore the stop-associated stimuli, the effects of stop learning are diminished or eliminated entirely. Across eight experiments, this thesis provides evidence that participants generate expectancies during stop learning that are consistent with the stimulus-stop contingencies in play. However, Experiments 5-6 indicate that there may be some differences in the relationships between stimulus-stop expectancies and task performance under instructed and uninstructed conditions; stimulus-stop associations that are acquired via task instructions or via task practice have similar effects on behaviour, but seem to differ in how they trigger response slowing for the stop-associated items. Experiments 7-8 investigated the role of signal detection processes during the acquisition of stimulus-stop associations. To distinguish between stimulus-stop learning and stimulus-signal learning, the contingencies between specific stimuli and the stop goal and the contingencies between specific stimuli and the spatial location of the stop signal were independently manipulated. Although these experiments showed evidence of stop/go (goal) learning, there was no evidence that participants acquired the stimulus-signal associations. Across four experiments, this thesis investigated the specificity of stop learning. Experiments 9-10 compared the effects of training on behavioural performance in inhibition (go/no-go) and non-inhibition (two-choice) tasks. The results of these experiments revealed that learning in inhibition and non-inhibition tasks could arise through similar associative mechanisms, but suggest that the effects of training in these tasks could also depend on top-down response settings and general non-associative processes. Experiments 11-12 investigated the neural specificity of stop learning. These experiments also revealed similar effects of training across the go/no-go and two-choice tasks adding weight to the claim that training in inhibition tasks primarily influences task-general processes. Combined, the overall conclusion of this thesis is that bottom-up control can influence response inhibition but what is learned depends on top-down factors. It is therefore important to consider bottom-up factors and top-down factors as dependent, rather than independent, influences on response inhibition.
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Narouei, Masoud. "A Top-Down Policy Engineering Framework for Attribute-Based Access Control." Thesis, University of North Texas, 2020. https://digital.library.unt.edu/ark:/67531/metadc1703379/.

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The purpose of this study is to propose a top-down policy engineering framework for attribute-based access control (ABAC) that aims to automatically extract ACPs from requirement specifications documents, and then, using the extracted policies, build or update an ABAC model. We specify a procedure that consists of three main components: 1) ACP sentence identification, 2) policy element extraction, and 3) ABAC model creation and update. ACP sentence identification processes unrestricted natural language documents and identify the sentences that carry ACP content. We propose and compare three different methodologies from different disciplines, namely deep recurrent neural networks (RNN-based), biological immune system (BIS-based), and a combination of multiple natural language processing techniques (PMI-based) in order to identify the proper methodology for extracting ACP sentences from irrelevant text. Our evaluation results improve the state-of-the-art by a margin of 5% F1-Measure. To aid future research, we also introduce a new dataset that includes 5000 sentences from real-world policy documents. ABAC policy extraction extracts ACP elements such as subject, object, and action from the identified ACPs. We use semantic roles and correctly identify ACP elements with an average F1 score of 75%, which bests the previous work by 15%. Furthermore, as SRL tools are often trained on publicly available corpora such as Wall Street Journal, we investigate the idea of improving SRL performance using domain-related knowledge. We utilize domain adaptation and semi-supervised learning techniques and improve the SRL performance by 2% using only a small amount of access control data. The third component, ABAC model creation and update, builds a new ABAC model or updates an existing one using the extracted ACP elements. For this purpose, we present an efficient methodology based on a particle swarm optimization algorithm for solving ABAC policy mining with minimal perturbation. Experimental results demonstrate that the proposed methodology generates much less complex policies than previous works using the same realistic case studies. Furthermore, we perform experiments on how to find an ABAC state as similar as possible to both the existing state and the optimal state. Part of the data utilized in this study was collected from the University of North Texas Policy Office, as well as policy documents from the university of North Texas Health Science Center, for the school years 2015-2016 through 2016-2017.
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Ma, Chuan. "A computational approach to top-down hierarchical supervisory control of DES." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0004/MQ45611.pdf.

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Clarke, Stephen E. "Top-down control of sensory focus in bursty pyramidal cell populations." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36826.

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Through a series of original research articles, this thesis describes the role of neural network feedback in top-down control of bursty ON and OFF type electrosensory neurons while processing motion toward (looming) and away (receding) from the body. Neural codes for motion reversal in weakly electric fish are not simply evoked by bottom-up sensory input and amplified by feedback; instead, positive feedback loops must synthesize a directionally invariant representation of motion reversal that is distributed across both the ON and OFF pyramidal cell populations. Through balanced excitatory and inhibitory feedback, the system establishes an optimal distance for motion estimation (a sensory focus) that is maintained by the animal during a motion tracking behaviour. Remarkably, this sensory focus is size, direction and speed-invariant. The speed invariance likely derives from the speed invariance of the electrosensory afferent response, a consequence of timescale-free spike frequency adaptation. Since natural swimming movements are associated with tail-bending that cause spatially diffuse sensory noise, we demonstrate that spatially localized motion processing by the ON and OFF neurons co-occurs with cancellation of the distraction; this supports the circuit's role as a robust `sensory searchlight' mechanism for spatial attention. A simple algorithm for motion tracking is discussed, as well as potential generalizations of the described coding principles to more complex mammalian circuits.
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Books on the topic "Contrôle top-down"

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Schwartz, R. Malcolm. A top-down approach to risk management and internal control: Relying on ongoing monitoring to test controls performance to reduce the scope of separate testing. Financial Executives Research Foundation, 2006.

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Honig, Dan. Introduction. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780190672454.003.0001.

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This chapter introduces the basic framework of the book. Agent judgment is fallible, and top-down controls may preclude useful actions by agents. International development organizations (IDOs), then, must choose between two flawed strategies in deciding whether to put agents in charge (Navigation by Judgment) or have principals retain control (Navigation from the Top). The extent to which environments are predictable and projects are externally verifiable affects how IDOs should manage interventions to increase intervention success and aid impact. This chapter introduces the quantitative and qualitative data that the book employs and previews how each chapter will contribute to the overall argument.
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Lippmann, Morton, and Richard B. Schlesinger. Risk Management. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780190688622.003.0010.

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This chapter describes the means that have been and can be used as management tools to limit chemical emissions and exposures to humans and other receptors that result in adverse effects. They include top-down mandates specified in enforceable exposure and/or emission standards (regulatory controls), bottom-up approaches involving control of access or requirements for the use of personal protective equipment (administrative controls), and various technologies that limit the use of chemicals (e.g., materials substitution) and/or capture and treat chemical wastes before their emissions to environmental media (engineering controls).
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Silliman, Brian R., Brent B. Hughes, Y. Stacy Zhang, and Qiang He. Business as usual leads to underperformance in coastal restoration. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198808978.003.0027.

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This chapter shows that coastal wetland projects are underperforming because of confirmation bias. Despite two decades of work showing that top-down control can be essential to marsh restoration, the potential role of top predators is typically ignored by those responsible for restoring or maintaining marshes. Similarly ignored are experiments that indicate positive interaction between marsh plants and can enhance the pace and success of restoration. By planting marsh plants at higher densities, marsh restoration success can double, and seagrass restoration can succeed in the face of increasing drought and eutrophication effects. Continued failure to integrate top-down control and facilitative species interactions into coastal restoration designs will result in widespread underperformance of wetland conservation projects and unrealized generation of important ecosystem services.
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Honig, Dan. When to Let Go. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780190672454.003.0002.

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This chapter illustrates what Navigation by Judgment is and some of its basic costs and benefits relative to Navigation from the Top. Navigation by Judgment is an organizational strategy in which front-line employees are able to meaningfully guide their organization’s work based upon their judgments. Key to Navigation by Judgment is that this judgment guides not merely the application of policy but also substantive strategic direction. This chapter introduces the basic trade-off between principal control and agent initiative as well as the parallel tension between Navigation by Judgment and top-down controls. It also differentiates Navigation by Judgment from autonomy and discretion.
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Miller, Earl K., and Timothy J. Buschman. Neural Mechanisms for the Executive Control of Attention. Edited by Anna C. (Kia) Nobre and Sabine Kastner. Oxford University Press, 2014. http://dx.doi.org/10.1093/oxfordhb/9780199675111.013.017.

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The prefrontal cortex is a source of internal control of attention as it captures three important components of an executive controller. First, it provides top-down selection of neural representations through descending projections, This top-down input may act by increasing the synchrony of local neural populations, enhancing their connectivity, and boosting the transmission of information. Second, intelligent top-down control of behaviour requires integrating diverse information. Neural representations in prefrontal cortex capture this breadth of information: representing anything from the specific contents of working memory to abstract categories and rules. Third, through reciprocal connections with the basal ganglia, prefrontal cortex neurons are ideally situated to learn the ‘rules’ of behaviour that allow us to know what to attend to in a given situation. These connections may support an iterative, bootstrapping, process that allows for increasingly complex rules to be learned. The prefrontal cortex acts as a generalized executive controller, acting through mechanisms such as attention, to guide thoughts and behaviour.
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Nigg, Joel T. Self-Regulation, Behavioral Inhibition, and Risk for Alcoholism and Substance Use Disorders. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780190676001.003.0009.

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Addiction liability involves multiple aspects of the person and the context. The within-person aspects can be organized within a broad temperament framework involving constituents of self-regulation. A fundamental dual-process model helps organize and structure the research program because self-regulation is conceived as involving both bottom-up and top-down capacities. From this perspective, addiction liability emerges and expresses itself in relation to early consolidation of bottom-up appetitive systems, organization of top-down control and executive processes, and progressive assembly of either self-regulation or its disruption in dysregulatory psychopathology such as attention-deficit/hyperactivity disorder and conduct problems. Several key studies supporting this hierarchical and sequential emergence of liability and addiction risk are summarized in this chapter.
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Nobre, Anna C. (Kia), and M.-Marsel Mesulam. Large-scale Networks for Attentional Biases. Edited by Anna C. (Kia) Nobre and Sabine Kastner. Oxford University Press, 2014. http://dx.doi.org/10.1093/oxfordhb/9780199675111.013.035.

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Selective attention is essential for all aspects of cognition. Using the paradigmatic case of visual spatial attention, we present a theoretical account proposing the flexible control of attention through coordinated activity across a large-scale network of brain areas. It reviews evidence supporting top-down control of visual spatial attention by a distributed network, and describes principles emerging from a network approach. Stepping beyond the paradigm of visual spatial attention, we consider attentional control mechanisms more broadly. The chapter suggests that top-down biasing mechanisms originate from multiple sources and can be of several types, carrying information about receptive-field properties such as spatial locations or features of items; but also carrying information about properties that are not easily mapped onto receptive fields, such as the meanings or timings of items. The chapter considers how selective biases can operate on multiple slates of information processing, not restricted to the immediate sensory-motor stream, but also operating within internalized, short-term and long-term memory representations. Selective attention appears to be a general property of information processing systems rather than an independent domain within our cognitive make-up.
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Butz, Martin V., and Esther F. Kutter. Attention. Oxford University Press, 2017. http://dx.doi.org/10.1093/acprof:oso/9780198739692.003.0011.

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Cognition does not work without attention. Attention enables us to focus on particular tasks and particular aspects in the environment. Psychological insights show that attention exhibits bottom-up and top-down components. Attention is attracted from the bottom-up towards unusual, exceptional, and unexpected sensory information. Top-down attention, on the other hand, filters information dependent on the current task-oriented expectations, which depend on the available generative models. This computational interpretation enables the explanation of conjunctive and disjunctive search. Different models of attention emphasize the importance of the unfolding interaction processes and a processing bottleneck can be detected. As a result, attention can be viewed as a dynamic control process that unfolds in redundant, neural fields, in which the selection of one interpretation and thus the processing bottleneck is strongest at the current focus of attention. The actual focus of attention itself is determined by the current behavioral and cognitive goals.
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Kirchman, David L. The ecology of viruses. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198789406.003.0010.

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In addition to grazing, another form of top-down control of microbes is lysis by viruses. Every organism in the biosphere is probably infected by at least one virus, but the most common viruses are thought to be those that infect bacteria. Viruses come in many varieties, but the simplest is a form of nucleic acid wrapped in a protein coat. The form of nucleic acid can be virtually any type of RNA or DNA, single or double stranded. Few viruses in nature can be identified by traditional methods because their hosts cannot be grown in the laboratory. Direct count methods have found that viruses are very abundant, being about ten-fold more abundant than bacteria, but the ratio of viruses to bacteria varies greatly. Viruses are thought to account for about 50% of bacterial mortality but the percentage varies from zero to 100%, depending on the environment and time. In addition to viruses of bacteria and cyanobacteria, microbial ecologists have examined viruses of algae and the possibility that viral lysis ends phytoplankton blooms. Viruses infecting fungi do not appear to lyse their host and are transmitted from one fungus to another without being released into the external environment. While viral lysis and grazing are both top-down controls on microbial growth, they differ in several crucial respects. Unlike grazers, which often completely oxidize prey organic material to carbon dioxide and inorganic nutrients, viral lysis releases the organic material from hosts more or less without modification. Perhaps even more important, viruses may facilitate the exchange of genetic material from one host to another. Metagenomic approaches have been used to explore viral diversity and the dynamics of virus communities in natural environments.
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Book chapters on the topic "Contrôle top-down"

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Frith, Chris D. "Free Will Top-Down Control in the Brain." In Understanding Complex Systems. Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-03205-9_12.

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Puaschunder, Julia M. "Top-Down Climate Control for Global Environmental Stability." In Climate Action. Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-319-71063-1_127-1.

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Lin, Alex Tong, Guido Montúfar, and Stanley J. Osher. "A Top-Down Approach to Attain Decentralized Multi-agents." In Handbook of Reinforcement Learning and Control. Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-60990-0_14.

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Teichberg, Mirta, Paulina Martinetto, and Sophia E. Fox. "Bottom-Up Versus Top-Down Control of Macroalgal Blooms." In Ecological Studies. Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-28451-9_21.

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Mishra, Ramesh Kumar, and Niharika Singh. "Chapter 17. Top down influence on executive control in bilinguals." In Cognitive Control and Consequences of Multilingualism. John Benjamins Publishing Company, 2016. http://dx.doi.org/10.1075/bpa.2.18mis.

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Trappenberg, Thomas, Pitoyo Hartono, and Douglas Rasmusson. "Top-Down Control of Learning in Biological Self-Organizing Maps." In Advances in Self-Organizing Maps. Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-02397-2_36.

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Brown, Guy C. "Phenomenological Kinetics and the Top-Down Approach to Metabolic Control Analysis." In Modern Trends in Biothermokinetics. Springer US, 1993. http://dx.doi.org/10.1007/978-1-4615-2962-0_36.

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Lee, Su-In, and Soo-Young Lee. "Top-Down Attention Control at Feature Space for Robust Pattern Recognition." In Biologically Motivated Computer Vision. Springer Berlin Heidelberg, 2000. http://dx.doi.org/10.1007/3-540-45482-9_13.

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Glibert, Patricia M. "Interactions of top-down and bottom-up control in planktonic nitrogen cycling." In Eutrophication in Planktonic Ecosystems: Food Web Dynamics and Elemental Cycling. Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-017-1493-8_1.

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Vargas, Natividad, Juan Luis del Valle-Padilla, Juan P. Jimenez, and Félix Ramos. "A Model of Top-Down Attentional Control for Visual Search Based on Neurosciences." In Brain-Inspired Cognitive Architectures for Artificial Intelligence: BICA*AI 2020. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-65596-9_65.

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Conference papers on the topic "Contrôle top-down"

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Khor, Susan. "On solving hierarchical problems with top down control." In the 2007 GECCO conference companion. ACM Press, 2007. http://dx.doi.org/10.1145/1274000.1274023.

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Skelton, James. "Top-down controls of the ambrosia beetle symbiont fidelity." In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.92485.

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Daofei Li, Bin Li, Fan Yu, Shangqian Du, and Yongchao Zhang. "A top-down integration approach to vehicle stability control." In 2007 IEEE International Conference on Vehicular Electronics and Safety (ICVES 2007). IEEE, 2007. http://dx.doi.org/10.1109/icves.2007.4456383.

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Levi, Hila, and Shimon Ullman. "Multi-Task Learning By A Top-Down Control Network." In 2021 IEEE International Conference on Image Processing (ICIP). IEEE, 2021. http://dx.doi.org/10.1109/icip42928.2021.9506501.

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Mallik, Sruti, and ShiNung Ching. "Top-down modeling of distributed neural dynamics for motion control." In 2021 American Control Conference (ACC). IEEE, 2021. http://dx.doi.org/10.23919/acc50511.2021.9482782.

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Lin, Liyong, Rong Su, and Alin Stefanescu. "Remarks on the difficulty of top-down supervisor synthesis." In 2012 12th International Conference on Control Automation Robotics & Vision (ICARCV 2012). IEEE, 2012. http://dx.doi.org/10.1109/icarcv.2012.6485170.

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White, Ralph N., and Edward O. Reese. "Optical telescope optimization through control system/mount top-down design." In Astronomical Telescopes and Instrumentation, edited by Thomas A. Sebring and Torben Andersen. SPIE, 2000. http://dx.doi.org/10.1117/12.393920.

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Price, Jeffery R., Philip R. Bingham, Kenneth W. Tobin, Jr., and Thomas P. Karnowski. "Semiconductor sidewall shape estimation using top-down CD-SEM image retrieval." In Quality Control by Artificial Vision, edited by Kenneth W. Tobin, Jr. and Fabrice Meriaudeau. SPIE, 2003. http://dx.doi.org/10.1117/12.514963.

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Aynaud, Claude, Coralie Bernay-Angeletti, Roland Chapuis, Romuald Auirere, and Christophe Debain. "Vehicle localization by using a multi-modality top down approach." In 2014 13th International Conference on Control Automation Robotics & Vision (ICARCV). IEEE, 2014. http://dx.doi.org/10.1109/icarcv.2014.7064523.

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Komenda, Jan, and Tomas Masopust. "Decentralized supervisory control with communicating supervisors based on top-down coordination control." In 2014 IEEE 53rd Annual Conference on Decision and Control (CDC). IEEE, 2014. http://dx.doi.org/10.1109/cdc.2014.7040194.

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