Dissertations / Theses on the topic 'Ressources cognitivess'
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Le, Gonidec Nolwenn. "Conceptualiser et évaluer la charge mentale de salariés dans un contexte d'usage d'outils numériques : Le cas d'une entreprise de télécommunications." Electronic Thesis or Diss., Université Côte d'Azur, 2022. http://www.theses.fr/2022COAZ2030.
Digital tools have taken over our daily professional life, facilitating telework but making us dependent on them. The latest French work regulations and several studies highlight the duality between their benefits and disadvantages for employees' activity. However, they are not taken into account in the conceptualization of the quality of life at work. Then, can they really be qualified as a help, and are they not harmful for the psychological health of employees? Our hypothesis is that these questions can be addressed by studying a key concept called a mental workload. Thus, our first study based on subjective interviews with call center operators, proves to the importance of the individual cognitive evaluation of the factors impacting mental workload. The second longitudinal study deals with employees in continuous telework situations and reveals the multifactorial and dynamic nature of mental workload over time. Finally, the third study highlights, with the help of a questionnaire, the importance of the context of use and the level of automation of digital tools on mental workload.These results contribute to the development of individual recommendations for the quality of work life of employees. Indeed, the employee will evaluate the impact of contextual factors according to his psychological state at the time. In addition, employees benefit from taking a step back from their practices, considering their resources and the adaptation strategies that can be implemented. It is a question of obtaining a balance between the demands of the tasks in each context and their available cognitive resources
Ragot, Isabelle. "Réduction des ressources cognitives, motivation au contrôle et recours aux "croyances"." Paris 10, 2001. http://www.theses.fr/2001PA100095.
In these researches, we try to explain why and how people recourse to irrational explanations (that can be designated by "beliefs" ) when they are faced with events that are rationally unexplainable. These researches are based on control theories, as they are defined in the literature as a fundamental need ; and particularly on works about consequences of control deprivation. A first research line, essentially cognitive, shows that the recourse to beliefs to explain an unexplainable event, is activated or inhibited by the rhetoric style used to tell the event. More accurately, the use of a "fantastic" rhetoric (with para factual lyric and symbolic indicators), compared with a factual rhetoric (without para factual lyric and symbolic indicators), constitute a source of cognitive noncontrol and, reducing the individual cognitive resources, lead people to recourse to the less costly solutions: explanations of an irrational type (the "beliefs"). A second research line explores cognitive and motivational processes underlying the recourse of "beliefs". The hypothesis is that recourse to beliefs, when people have to explain an explainable event, can also be motivated by research of control. Some results are observed in this way, accompanied with a reduction of the performance in a future cognitive task
Imbert, David. "Pluralité des voies d'acquisition du comptage, ressources cognitives et acquisitions numériques." Nantes, 2005. http://www.theses.fr/2005NANT3017.
This research, undertaken with preschool children, aims at showing that each of the classical models of the counting acquisition mirrors a different cognitive processing. A differentiation process, taking place during the development, suggests the existence of three distinct ways of acquisition, each of them being underlaid by specific cognitive resources. Some children would chiefly make use of the conceptual knowledge related to counting. Others, by the way of the numerical chain, would first acquire explicit knowledge about counting. These two subtypes of cognitive processing would rely upon a greater aptitude to inhibit irrelevant information in the former case, and on better memory capacities in the latter case. A last path is exemplified by children whose cognitive resources are diversified. Besides, such discrete acquisition profiles would be predictive of the development of more complex numerical capacities (simple additions and subtractions, numerical transcribing. . . )
Le, Quellec Sandrine. "Etat émotionnel et mobilisation des ressources cognitives chez la personne âgée." Tours, 2003. http://www.theses.fr/2003TOUR2022.
Zayen, Bassem. "Stratégies d'accès et d'allocation des ressources pour la radio cognitive." Phd thesis, Télécom ParisTech, 2010. http://pastel.archives-ouvertes.fr/pastel-00576459.
Zayen, Bassem. "Stratégies d'accès et d'allocations des ressources pour la radio cognitive." Paris, Télécom ParisTech, 2010. https://pastel.hal.science/pastel-00576459.
Cognitive radio is a promising technique for efficient spectrum utilization. It must dynamically monitors activity in the primary spectrum and adapts its transmission to available spectral resources. The blind spectrum sensing and resource allocation in cognitive radio are being addressed in this thesis. The aim of the first part of this research has been to investigate whether model selection or signal space dimension estimation and information theoretic distance measures could be used to improve spectrum detection performance in a blind way and low signal to noise region. Through a thorough research effort, two novel spectrum sensing algorithms based on distribution analysis and dimension estimation of the primary user received signal were proposed and analyzed. The second part of this thesis presents and analyzes two user selection strategies based on outage probability. One explored the idea of combining multi-user diversity gains with spectral sharing techniques to maximize the secondary users sum rate while maintaining the outage probability of the primary user not degraded with a distributed manner, the other treat the beamforming problem in the context of cognitive radio using multiuser MIMO secondary user system and proposes a user selection strategy based on outage probability
Bernardin, Sophie. "Mémoire de travail et contraintes cognitives : le modèle du partage temporel des ressources." Dijon, 2004. http://www.theses.fr/2004DIJOL013.
Monetta, Laura. "Déficits lexico-sémantiques conséquents à une lésion droite un problème de ressources cognitives? /." [Montréal] : Université de Montréal, 2002. http://wwwlib.umi.com/cr/umontreal/fullcit?pNQ82745.
"NQ-82745." "Thèse présentée à la faculté des études supérieures en vue de l'obtention du grade de philosophiae doctor (Ph. D.) en sciences biomédicales, option orthophonie." Version électronique également disponible sur Internet.
Bey, Christophe. "Gestion des ressources cognitives et stratégies d'adaptation court terme chez les pilotes d'aéronefs." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0428/document.
The aviation industry has for many years pursued the objective of an optimum level of safetyin the air transport sector. With regard to military aviation, more precisely tactical, thispriority is coupled with an increasingly high and polymorphic search for performance. Whatcharacterize this type of aviation is the relationship between the performance pursued and theaccepted risks. It depends essentially on the context and the stakes of the missions to becarried out.The human factor approach is a major leverage for achieving this challenge. Thus, within theconstrained domain of aeronautics, the design and development of tools to assist crewcognition remains a prospect for the future, even if pilot training also becomes a majorchallenge for the coming years. In this context, the management of cognitive resources, and inparticular the specific management strategies put in place by the pilots, are central to thedecision-making process under constraints.In a research and engineering approach in cognition, we undertook a study involving pilotsand allowing the understanding of these mechanisms as well as the production ofrecommendations for the design of tools to help manage their cognitive resources. On thebasis of the analysis of feedback, and results of a preliminary experimental approach, we havebuilt a protocol to highlight the strategies implemented by the pilots in the context of anactivity during the descent and the final approach on the Clermont-Ferrand airport with acritical breakdown. The experimental results reconciled with our understanding hypotheseson the management of cognitive resources and management strategies, complete our analysisand recommendations for a tool to help manage the resources of the pilots
Volpe, Rosa. "Attention, métacognition et gestion des ressources cognitives en mémoire : vers une approche néopiagétienne de l'écrit." Thesis, Université Côte d'Azur (ComUE), 2016. http://www.theses.fr/2016AZUR2026/document.
This dissertation studies writing under the metacognitive and metasubjective perspectives from Pascual-Leone’s Theory of Constructive Operators (1976, 1984, 1987, 1989, 1995, 1997, 1998, 2000, 2001, 2012, 2013) et d’Efklides (2001, 2002, 2006, 2008, 2011, 2013). Research on writing emphases the role working memory plays on the processes underlying it (cf. Alamargot & Chanquoy, 2001 for a review of the literature ; Olive, 2012), namely how the limited capacity of working memory affects children’s difficulties in writing. The notion of guided training (Pascual-Leone & Johnson, 2011) is here adopted suggesting the explicit implementation of metacognition, generally defined as thinking about thinking (Flavell, 1979), to manage mental attention resources while enhancing working memory performance, and as a consequence, written performance.This being said, the following questions apply: does training primary school children to develop metacognitive knowledge and abilities contribute to activate (inhibit) (non)pertinent knowledge while dispelling their feeling of difficult about writing?The experimental studies conducted within this research focus on the metaconsctructive system of the theory of constructive operators: the learning system, the attention system and the personal system. Results show that 3rd, 4th and 5th graders are able to develop new metacognitive knowledge about writing, furthermore, primary school children succeed in better handling the cognitive resources required by the task
Batt, Marie. "Les effets de l’engagement par le brouillon sur des scripteurs au collège." Thesis, Bordeaux 2, 2012. http://www.theses.fr/2012BOR21918/document.
When a professor of french encourages a student to produce a draft, at first, he looks for to act on the writer’s behavior by producing a writing which leads him to carry out a revision of its text. It is then an action that is expected : the one of a review of the writings which materializes under the stroke of erasures. The purpose of a draft don’t stops here. It concerns as much the writer’s attitudes by facing a text that is not in form of a final writing or a dictation deriving from inspiration’s sources but as a work, as an elaboration. This study, through the commitment theory attempts to cover the behavioral and cognitive consequences linked to the completion of a draft. For that purpose, the analysis based on the kind of the erasures covers the drafts of 253 writers pertaining to the 6th and 3rd classes. Besides, a questionnaire gives information about the appearance of cognitive effects. The results either show the commitment situation, the problematic aspects raised by the redaction and the draft or the behavioral and cognitive effects characteristics depending on the writer’s expertise
Trigui, Emna. "Gestion multi-agents du spectre pour des terminaux mobiles à radio cognitive." Thesis, Troyes, 2013. http://www.theses.fr/2013TROY0026/document.
In this thesis, we are interested in mobile cognitive radio networks while ensuring an efficient spectrum sharing and seamless handover at the same time. Hence, we propose two decentralized approaches based on multi-agents systems. We first deployed agents on each primary (licensed) and secondary (unlicensed cognitive radio) users, respectively. Besides, we define agents’ behaviors during the handover process.Our proposal NESAM defines a novel negotiation mechanism between agents to allow secondary users assigning the appropriate spectrum band giving a good price for the use duration. We have also proposed a second solution LASMA using the learning based auctions. Our algorithms take into account users’ requirements such as spectrum frequency, price and duration as well as environment’s constraints such as available resources.Our proposals improve the overall spectrum utilization and minimize the number of spectrum handovers when users move from one network to another one. This proves that our algorithms ensure efficient spectrum allocation and enable seamless handover during user’s mobility. Besides, we proved that our approaches guarantee users’ satisfaction and improve their utility
Hoch, Lisianne. "Perception et apprentissage des structures musicales et langagières : études des ressources cognitives partagées et des effets attentionnels." Thesis, Lyon 2, 2010. http://www.theses.fr/2010LYO20049/document.
Music and language are structurally organized materials that are based on combinatorial principles. Listeners have acquired knowledge about these structural regularities via mere exposure. This knowledge allows them to develop expectations about future events in music and language perception. My PhD investigated two aspects of domain-specificity versus generality of cognitive functions in music and language processing: perception and statistical learning.In the first part (perception), musical structure processing has been shown to influence spoken and visual language processing (Études 1 & 4), partly due to dynamic attending mechanisms (Jones, 1976). More specifically, musical structure processing has been shown to interact with linguistic-syntactic processing, but not with linguistic-semantic processing (Étude 3), thus supporting the hypothesis of shared syntactic resources for music and language processing (Patel, 2003). Together with previous studies that have investigated simultaneous musical and linguistic (syntactic and semantic) structure processing, we proposed that these shared resources might extend to the processing of other structurally organized information that require structural and temporal integration resources. This hypothesis was tested and supported by interactive influences between simultaneous musical and arithmetic structure processing (Étude 4). In the second part (learning), statistical learning was directly compared for verbal and nonverbal materials. In particular, we aimed to investigate the influence of dynamic attention driven by non-acoustic (Études 5 & 6) and acoustic (Étude 7) cues on statistical learning. Non-acoustic temporal cues have been shown to influence statistical learning of verbal and nonverbal artificial languages. In agreement with the dynamic attending theory (Jones, 1976), we proposed that non-acoustic temporal cues guide attention over time and influence statistical learning.Based on the influence of dynamic attending mechanisms on perception and learning and on evidence of shared structural and temporal integration resources for the processing of musical structures and other structured information, this PhD opens new questions about the potential influence of tonal and temporal auditory structure processing on general cognitive sequencing abilities, notably required in structured sequence perception and learning.Jones, M. R. (1976). Time, our lost dimension: Toward a new theory of perception, attention, and memory. Psychological Review, 83(5), 323-355. doi:10.1037/0033-295X.83.5.323Patel, A. D. (2003). Language, music, syntax and the brain. Nature Neuroscience, 6(7), 674-681. doi:10.1038/nn1082
Denis, Juwendo. "Resource Allocation Frameworks for Multi-carrier-based Cognitive Radio Networks with full and Statistical CSI." Electronic Thesis or Diss., Paris, CNAM, 2016. http://www.theses.fr/2016CNAM1069.
The ubiquity and proliferation of wireless technology and services considerably lead to a sharp increase in the number of individuals requiring access to wireless networks in recent decades. The growing number of mobile subscribers results into a dramatic increasing request for more radio spectrum. Consequently, underutilized yet scarce radio spectrum becomes overwhelmingly crowded. Therefore, the advent of new radio resource management paradigm capable of switching from static licensed spectrum management to dynamic spectrum access is of great importance. Cognitive radio (CR) emerged as a promising technology capable of enhancing the radio spectrum by permitting unlicensed users known as secondary users to coexist with primary users. Meanwhile, multi-carrier modulations that can efficiently overcome the detrimental effect of multipath fading in a wireless channel are very appealing for the physical layer of cognitive radio networks. However, the lack of cooperation between primary and secondary users may lead to asynchronous transmission and consequently result into inter-carrier interferences. Judicious resource allocation frameworks need to be designed in order to maintain the coexistence between primary and secondary users. Guaranteeing secondary users' quality of service (QoS), while ensuring that interferences generated to the primary users are tolerable, poses significant challenges for the design of wireless cognitive radio networks. This dissertation focuses on resource, i.e. subcarrier and power, allocation for multi-carrier-based downlink cognitive radio networks under perfect or statistical channel state information (CSI) with secondary users interact either cooperatively or competitively. Firstly, the problem of margin adaptive and energy-efficiency optimization are investigated considering perfect CSI at the secondary users' side. Secondly, assuming statistical CSI available at the secondary users, we address the problem of utility maximization under primary and secondary outage constraints. We provide some near-optimal resource allocation schemes to tackle the aforementioned problems. The findings and proposed frameworks can eventually be used for performance assessment and design of practical cognitive radio networks
De, Domenico Antonio. "Technique de gestion de ressources radios pour l'amélioration de l'efficacité énergétique dans les réseaux cellulaires hétérogènes." Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENM012/document.
Wireless communication proliferates into nearly each aspect of the human society, driving to the exponential growth in number of permanently connected devices. Powerful smart-phones and tablets, ubiquitous wireless broadband access, and machine-to-machine communications gen- erate volumes of data traffic that were unpredictable few years back. In this novel paradigm, the telecommunication industry has to simultaneously guarantee the economical sustainability of broadband wireless communications and users' quality of experience. Additionally, there is a strong social incentive to reduce the carbon footprint due to mobile communications, which has notably increased in the last decade. In this context, the integration of femtocells in cellular networks is a low-power, low-cost solution to offer high data rates to indoor customers and simultaneously offload the macrocell network. However, the massive and unplanned deployment of femtocell access points and their uncoordinated operations may result in harmful co-channel interference. Moreover, a high number of lightly loaded cells increases the network energy consumption. In this thesis, we investigate the effects of femtocells deployment on the cellular network energy efficiency. Moreover, we look into adaptive mechanisms for femtocell networks as a means to pave the way towards agile and economically viable mobile communications. Our goal is to dynamically match resource demand and offered capacity in order to limit the average power consumption and co-channel interference while guaranteeing quality of service constraints. We take advantage of the unusual communication context of femtocells to propose resource allocation and network management schemes that coordinate the access points activity, power consumption, and coverage. Simulation results show that our proposals improve system energy efficiency and users' performance in both networked and stand-alone femtocell deployment scenarios
Cance, Caroline. "Expériences de la couleur, ressources linguistiques et processus discursifs dans la construction de l'espace visuel : l'habitacle automobile." Paris 3, 2008. https://tel.archives-ouvertes.fr/tel-00353095.
This research anchors the analysis of relations of co-construction between discourse and perception, and representations and knowledge, in linguistics and cognitive psychology. Grounding the work in the holistic aspect of perception, a methodology of semi-directed interviews was set up in order to identify the factors involved in the visual assessment of automobile interiors. Four types of discourse in four different perceptive situations of the interiors were elicited and collected (interviews of memorised experiences of automobile interiors versus interviews in “front of” and “inside” experimental 2D and 3D devices and real cars). Contrastive analyses at lexical, morpho-syntactic and discourse levels allow for inferences on cognitive constructions built in discourse to be brought out. Regularities and specificity, in the way of referring to as well as evaluating sensory characteristics of this complex space, were found to be related to the degree of familiarity of speakers with the technical device by which they experienced the interiors. The contrasts between the modes of material presentation allowed for different conceptualisations of colours co-built in discourse to be identified: entity and property. These different conceptualisations also serve to support the (re)construction of the materiality of a space deprived of tactile and kinaesthetic clues. This research contributes to the construction of a situated cognitive semantics whose purpose is to underline the dynamics of co-construction between sensory experience, knowledge, linguistic materiality and discursive practices
Mir, Usama. "Utilization of cooperative multi-agent systems for spectrum sharing in cognitive radio networks." Troyes, 2011. http://www.theses.fr/2011TROY0008.
Static spectrum allocation is a major problem in recent wireless networks. This scarcity problem is temporary and can be alleviated if the spectrum access is performed dynamically. Cognitive radio (CR) is an important new technology which addresses dynamic spectrum access challenges in detail. These challenges include efficient allocation of spectrum for primary (or licensed) and CR (or secondary) users in order to increase spectrum usage and to avoid user conflicts. Therefore, in this research we are interested in developing novel solutions for dynamic and efficient spectrum access under (1) licensed bands where CR users attempt to use the spec-trum by coexisting with the primary users and (2) unlicensed bands where the CR users try to access the spectrum by avoiding conflicts with their neighbors. In our first proposal, we deploy agents over each primary and CR users which allow them to work cooperatively in order to make spectrum access agreements. The simulation results show that our approach achieves good performance in terms of spectrum access, sustaining lower communication overhead. Our second proposal focuses on unlicensed spectrum access where spectrum can be viewed as an open ‘pool’ and no user has an exclusive license for spectrum access. Using multi-agent system, the CR users cooperate and they form several coalitions. These types of coalitions can provide a less-conflicted access as the agents mutually agree for spectrum sharing. The important comparisons between analytical and simulation results in terms of blocking probability verify the relevance of our approach in CR context
Bouallegue, Kaïs. "Contribution à la radio intelligente à forte mobilité : adaptation spectrale et allocation dynamique des ressources." Thesis, Valenciennes, 2017. http://www.theses.fr/2017VALE0023.
The main objectives of railway operators are to increase safety, reduce operating and maintenance costs, increase attractiveness and profit by offering new services to customers. These objectives will be achieved through a huge increase of data fluxes between existing infrastructure and the technologies currently used on the train. Spectral efficiency, optimization of radio resources, interoperability and reliability of communications are major elements for railway applications. These constraints and the sporadic use of available frequency bands have gave rise to cognitive radio. Cognitive radio is an emerging technology that improves the performance of existing radio systems by integrating artificial intelligence with software radio. A cognitive radio system is defined by its ability to be aware of its radio environment. Indeed, to optimize as much as possible the available spectral opportunities, the cognitive radio device must be able to transmit on free bands while performing a spectrum sensing to not interfere with users having priority on the band and to detect other vacant frequencies. As part of this thesis, we propose to focus on the problem of spectrum detection in a highly mobile environment. Some constraints should be considered, such as speed. Added to this, there are regulatory constraints on detection criteria, such as the IEEE 802.22 WRAN standard, which stipulates that detection of a priority user must be performed at -21 dB within a period of 2 seconds. The objective is therefore to design an intelligent radio terminal in the physical and regulatory conditions of transmission in a railway environment
Denis, Juwendo. "Resource Allocation Frameworks for Multi-carrier-based Cognitive Radio Networks with full and Statistical CSI." Thesis, Paris, CNAM, 2016. http://www.theses.fr/2016CNAM1069/document.
The ubiquity and proliferation of wireless technology and services considerably lead to a sharp increase in the number of individuals requiring access to wireless networks in recent decades. The growing number of mobile subscribers results into a dramatic increasing request for more radio spectrum. Consequently, underutilized yet scarce radio spectrum becomes overwhelmingly crowded. Therefore, the advent of new radio resource management paradigm capable of switching from static licensed spectrum management to dynamic spectrum access is of great importance. Cognitive radio (CR) emerged as a promising technology capable of enhancing the radio spectrum by permitting unlicensed users known as secondary users to coexist with primary users. Meanwhile, multi-carrier modulations that can efficiently overcome the detrimental effect of multipath fading in a wireless channel are very appealing for the physical layer of cognitive radio networks. However, the lack of cooperation between primary and secondary users may lead to asynchronous transmission and consequently result into inter-carrier interferences. Judicious resource allocation frameworks need to be designed in order to maintain the coexistence between primary and secondary users. Guaranteeing secondary users' quality of service (QoS), while ensuring that interferences generated to the primary users are tolerable, poses significant challenges for the design of wireless cognitive radio networks. This dissertation focuses on resource, i.e. subcarrier and power, allocation for multi-carrier-based downlink cognitive radio networks under perfect or statistical channel state information (CSI) with secondary users interact either cooperatively or competitively. Firstly, the problem of margin adaptive and energy-efficiency optimization are investigated considering perfect CSI at the secondary users' side. Secondly, assuming statistical CSI available at the secondary users, we address the problem of utility maximization under primary and secondary outage constraints. We provide some near-optimal resource allocation schemes to tackle the aforementioned problems. The findings and proposed frameworks can eventually be used for performance assessment and design of practical cognitive radio networks
Trémolière, Bastien. "La rationalité des mortels : les pensées de mort perturbent les processus analytiques." Phd thesis, Université Toulouse le Mirail - Toulouse II, 2013. http://tel.archives-ouvertes.fr/tel-00979659.
Ben, Hadj Alaya-Feki Afef. "Métrologie dans les réseaux d'accès radio pour la gestion des ressources pour le développement du concept "Always Best Connected"." Paris, ENST, 2008. https://pastel.hal.science/pastel-00005011.
The main goal of the thesis is to propose effective approaches dealing with information collection, processing and utilization in cognitive radio context. These works are motivated by the necessity for wireless networks to cope with the increasing demand of throughput and services on one hand, and the inefficient use of spectral resources on the other hand. In chapter 1, we propose to integrate advanced radio signal processing in Radio Resource Management (RRM) mechanisms in order to realize an effective and easy-to-implement exploitation of radio measurements, leading to an overall RRM improvement. Thus, we propose a complete framework that performs a signal processing analysis, based on non-parametric regression and smoothing methods. In chapter 2, we propose a novel concept: the interference cartography. It combines location information with radio measurements and provides a complete view of the environment to be used in autonomous decision making in a cognitive context. Our study deals with advanced signal processing techniques to render the information complete and reliable, and updating the cartography to provide a viable picture of the environment for efficient analysis and decision. In chapter 3, our interest turns to opportunistic spectrum access. The proposed approach is inspired from Multi Armed Bandit problem: a reinforcement learning technique that guides the secondary user thanks to appropriate rules and policies. Our study deals with the application of this approach on IEEE802. 11 systems for the realization of opportunistic spectrum access, as well as the tuning of the algorithms’ parameters for better performances in non-stationary environments
Castillo, Brieva Daniel. "Arrangements institutionnels et modèles mentaux dans la gestion des ressources en bien commun." Paris 10, 2013. http://www.theses.fr/2013PA100022.
De, domenico Antonio. "Technique de gestion de ressources radios pour l'amélioration de l'efficacité énergétique dans les réseaux cellulaires hétérogènes." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00720622.
Cance, Caroline. "Expériences de la couleur, ressources linguistiques et processus discursifs dans la construction d'un espace visuel : l'habitacle automobile." Phd thesis, Université de la Sorbonne nouvelle - Paris III, 2008. http://tel.archives-ouvertes.fr/tel-00353095.
Pralong, Jean. "Les mondes de la carrière. Approche socio-cognitive du succès objectif de carrière des cadres français." Thesis, Paris 10, 2009. http://www.theses.fr/2009PA100186.
Career success is traditionally defined as objective or subjective. In a complex and changing economy, it is more and more important to understand the determinants of objective career success. Human capital and cultural capital are regular predictors to objective career success. But organizations have changed. Careers unfold in ambiguous, but ongoing and valued contexts. In such contexts, individuals must make sense by themselves concerning decisions to be made, opportunities to be constructed or occurrences that may be undergone. For this purpose they use a repertoire of cognitive schemas that constitute a career frame of reference. Hypotheses A suggest that the career frame of reference is a moderator of the influence of human capital and of cultural capital on objective career success. Reciprocally, careers and organizations shape the career frame of reference. Thus, hypotheses B claim that the type of careers has an influence on the career frame of reference.Three methods were used: qualitative pre-survey, scales development and cognitive mapping (602 individuals). Cognitive maps were constructed thanks to a new technique that helps avoiding the biases. Factorial analyses show that the career frame of reference is a four-dimensional construct. The four dimensions describe the “career worlds”, i.e. the shareholders and the associated beliefs involved in one’s career. Data collected show the radicalization of objective career success differences among French executives. Hypotheses A are partially supported by the data. Objective career success is predicted by human capital, but it is moderated by the career frame of reference. Competencies are not enough to reach objective career success. Career frame of reference has a pragmatic and symbolic efficiency: successful careerists’ frame of reference validate norms and ideologies about the efficiency of free job markets and fair competition among employees for achievement. Hypotheses B are supported by the data. The type of careers leads to specific career frame of reference
Ayora, Pauline. "Recrutement de ressources attentionnelles au cours de la production du langage." Thesis, Aix-Marseille 1, 2011. http://www.theses.fr/2011AIX10072.
Language production is a cognitive activity long studied in isolation from more general cognitive processes that could underlie its achievement. Our approach aimed to contribute to the emerging dynamics of the opening of psycholinguistics to other domains of cognitive psychology by specifying how linguistic mechanisms interact with attentional mechanisms. To do so, we first investigated to which extent producing a single linguistic unit relies on selection mechanisms. Also, we highlighted the attentional mechanisms underlying these lexical selection mechanisms: The selections of two types of grammatical words were compared: open- and closed- class words. Results revealed that the selections of both, closed-class words structuring the phrase, and open-class words conveying meaning, require attentional resources. In a third study, we showed that the semantic interference effect - affecting a competition mechanism supposedly taking place at the level of lexical selection- can in fact be resolved before the involvement of central attentional resources. This suggests that this semantic interference effect possibly reflects a mechanism taking place prior to lexical selection. In a last study, we explored the temporal dynamics of our production system when engaged in the selection of several words within a sequence, using noun phrases. Chronometric results revealed that words are selected strictly sequentially. This dynamics suggests that the way attentional resources are recruited for the selection of an isolated linguistic unit can constrain the way several words are produced in a more natural speaking context
Jouini, Wassim. "Contribution to learning and decision making under uncertainty for Cognitive Radio." Thesis, Supélec, 2012. http://www.theses.fr/2012SUPL0010/document.
During the last century, most of the meaningful frequency bands were licensed to emerging wireless applications. Because of the static model of frequency allocation, the growing number of spectrum demanding services led to a spectrum scarcity. However, recently, series of measurements on the spectrum utilization showed that the different frequency bands were underutilized (sometimes even unoccupied) and thus that the scarcity of the spectrum resource is virtual and only due to the static allocation of the different bands to specific wireless services. Moreover, the underutilization of the spectrum resource varies on different scales in time and space offering many opportunities to an unlicensed user or network to access the spectrum. Cognitive Radio (CR) and Opportunistic Spectrum Access (OSA) were introduced as possible solutions to alleviate the spectrum scarcity issue.In this dissertation, we aim at enabling CR equipments to exploit autonomously communication opportunities found in their vicinity. For that purpose, we suggest decision making mechanisms designed and/or adapted to answer CR related problems in general, and more specifically, OSA related scenarios. Thus, we argue that OSA scenarios can be modeled as Multi-Armed Bandit (MAB) problems. As a matter of fact, within OSA contexts, CR equipments are assumed to have no prior knowledge on their environment. Acquiring the necessary information relies on a sequential interaction between the CR equipment and its environment. Finally, the CR equipment is modeled as a cognitive agent whose purpose is to learn while providing an improving service to its user. Thus, firstly we analyze the performance of UCB1 algorithm when dealing with OSA problems with imperfect sensing. More specifically, we show that UCB1 can efficiently cope with sensing errors. We prove its convergence to the optimal channel and quantify its loss of performance compared to the case with perfect sensing. Secondly, we combine UCB1 algorithm with collaborative and coordination mechanism to model a secondary network (i.e. several SUs). We show that within this complex scenario, a coordinated learning mechanism can lead to efficient secondary networks. These scenarios assume that a SU can efficiently detect incumbent users’ activity while having no prior knowledge on their characteristics. Usually, energy detection is suggested as a possible approach to handle such task. Unfortunately, energy detection in known to perform poorly when dealing with uncertainty. Consequently, we ventured in this Ph.D. to revisit the problem of energy detection limits under uncertainty. We present new results on its performances as well as its limits when the noise level is uncertain and the uncertainty is modeled by a log-normal distribution (as suggested by Alexander Sonnenschein and Philip M. Fishman in 1992). Within OSA contexts, we address a final problem where a sensor aims at quantifying the quality of a channel in fading environments. In such contexts, UCB1 algorithms seem to fail. Consequently, we designed a new algorithm called Multiplicative UCB (UCB) and prove its convergence. Moreover, we prove that MUCB algorithms are order optimal (i.e., the order of their learning rate is optimal). This last work provides a contribution that goes beyond CR and OSA. As a matter of fact, MUCB algorithms are introduced and solved within a general MAB framework
Jin, Xin. "Resource allocation in multicarrier cognitive radio networks." Electronic Thesis or Diss., Evry, Institut national des télécommunications, 2014. http://www.theses.fr/2014TELE0014.
In view of the wide usage of multicarrier modulation in wireless communications and the prominent contribution of Cognitive Radio (CR) to deal with critical shortage of spectrum resource, we focus on multicarrier based cognitive radio networks to investigate general resource allocation issues: subcarrier allocation, power allocation, routing, and beamforming in this thesis. We investigate two types of multicarrier modulation: Wavelet-based Orthogonal Frequency Division Multiplexing (WOFDM) and Fourier-based Orthogonal Frequency Division Multiplexing (OFDM). WOFDM adopts Wavelet Packet Modulation (WPM). Compared with fourier-based OFDM, wavelet-based OFDM achieves much lower side lobe in the transmitted signal. Wavelet-based OFDM excludes Cyclic Prefix (CP) which is used in fourier-based OFDM systems. Wavelet-based OFDM turns to exploit equalization to combat Inter-Symbol Interference (ISI). We evaluate the performance of WOFDM under different channel conditions. We compare the performance of wavelet-based OFDM using equalization in the time domain to that of fourier-based OFDM with CP and the equalization in the frequency domain
Fenianos, Johnny. "Entre Psychologie et Ecologie : approche psycho socio écologique de la restauration des carrières en région méditerrannéenne (cas du Liban)." Thesis, Montpellier 3, 2018. http://www.theses.fr/2018MON30024/document.
If the future of our planet depends indeed on the mastering of the « young discipline” that is ecological restauration, as confirmed in Roberts et al. (2009), it is our duty to invest in the preservation and improvement of ecosystem services, ecological connectivity and biological cycles that rely on the functioning of corrupted ecosystems. Mediterranean ecosystems knowledge and the mastering of ecological engineering techniques have made substantial progress during the last decades. Unfortunately, the transfer of these techniques on the field and their implementation are still sparse, and notably in environments where consistent interactions with human communities require the appropriation and adoption of intervention methods. The Mediterranean basin, which is considered a hotspot for diversity, evolves in tense and often unstable sociopolitical conditions, along with huge demographic increase, poorly-planned urbanization and a long history of coevolution of men and landscapes dating back to the Neolithic period. This makes this transfer of techniques yet more complex. In this context, how can we overcome the resistance and win acceptance on the proposed technical solutions? How can we bring people to better accept modifications relating to their life environments? Is it possible to initiate an attitude and behavioral change towards the proposed solutions? In other words, can we induce acceptance for the intervention techniques and methods on an environment/ecosystem when these are met with the stereotypes disseminated by the concerned human communities? Starting from these questions, this thesis wishes to address a specific problematic: how can we change the behaviors of individuals towards the modifications of their close environment? The original hypothesis is the following: by influencing the processes underlying behavioral change, we can improve the acceptation of the principle and intervention techniques relating to environmental action. Should we wish to initiate a change in attitude, we need to modify the “action to object” relations, which are mainly slowed down by the consistency of individuals. We therefore need to modify, not only their cognitive flexibility, but also their emotional experience and affordance. Thus, the operational hypotheses break down as follows: H1: Cognitive flexibility and attitude change: by improving cognitive flexibility, it is possible to increase acceptability towards the principle and techniques of intervention relating to environmental action. H2: Emotional experience and attitude change: A person’s emotional experience and their space perception can induce a change in attitude towards the principle and techniques of intervention relating to environmental action. H3: Affordance and attitude change: A change in affordance can contribute to initiate a change in attitude in a person towards the principle and techniques of intervention relating to environmental action. These hypotheses will be tested on the example of quarries rehabilitation in Lebanon – in a Mediterranean context
Mei, Maryline. "Les ressources numériques comme support aux fonctions d'étayage de l'élève tuteur : cas d'un dispositif en sciences à l’école élémentaire." Thesis, Sorbonne Paris Cité, 2018. https://wo.app.u-paris.fr/cgi-bin/WebObjects/TheseWeb.woa/wa/show?t=1259&f=15369.
The thesis focuses on benefits which the use of digital resources available in primary school is likely to bring to tutoring situations, practised between pupils of CP and CE1. It questions anew the relevance of entrusting the role of tutor to young children, since the functionalities of digital environments would make it possible to lighten their scaffolding functions, so that they'll become more comfortable in their mission. In light of the researches already conducted on peer tutoring and the use of digital technology in primary school, our research proposes to observe if the specificities of digital environments can encourage in young tutors the emergence of two components of a tutoring situation favourable to both partners: the "cognitive congruence" and the "tutor-effect". Our protocol is part of the school program (2015) of the Ministry of National Education, Higher Education and Research: use digital tools, encourage peer help behaviour. Knowledge to be worked on is based on the understanding of simple scientific phenomena (the matter / states of water). The protocol is built on a pre-test, an experimental phase (correction session then training) and two post-tests. Post-test 1 proposes to reinvest the knowledge learnt during the experimental phase. Post-test 2 is identical to the pre-test. These tests are offered to CP and CE1 pupils working either in a tutoring situation, or in pairs with no assigned role, or individually. Within each group, a distinction is made according to whether CP pupils use a paper booklet or a computer. Our goal is to put the digital environment at the service of the tutorial relationship rather than learning itself. A first analysis, quantitative, compares the test results of each group by distinguishing, on the one hand, the level of the pupils and, on the other hand, the involved medium. It aims to check whether the use of a new environment allows both partners of the digital tutoring dyads to significantly progress, not only compared to pupils from the other groups, but also - and above all - compared to their counterparts who worked on a paper booklet. Regardless of the forms of work, our results indicate a progression of the scores of all the groups at the two post-tests but the only use of a different medium (paper or computer) does not influence the success of the pupils. On the matching between forms of work and medium, we find that, even in an ad hoc educational device, the digital medium does not allow tutees and tutors to pass their tests better than their peers using paper. The progression of the tutees and the "tutor-effect" expected in this context are therefore not observed. A second qualitative analysis focuses on the content of the exchanges between tutors and their tutee, depending on whether they interact by working on a paper booklet or on a computer. The observation focuses on the verbal and nonverbal aspects, in order to account for the cognitive congruence of the tutor. The Elan software allows the annotation of filmed exchanges. An overall analysis shows that congruence, if it is observable in the tutor, is not a relevant indicator to guarantee for the success of the tutee. On the other hand, a more detailed analysis reveals a link between the tutor's perception of his function and the success of his tutee
Pottier, Antony. "Méthodes décentralisées d'allocation des ressources dans le canal d'interférence acoustique sous-marin." Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2018. http://www.theses.fr/2018IMTA0095/document.
Underwater acoustic waves are used by many systems and biologic organisms to communicate, navigate or infer information about the environment. Future developments of human maritime activities imply an increase of the number of active acoustic sources in the oceans. The underwater environment is therefore shared by many heterogeneous sources (sonars, modems, marine mammals, ...) competing involuntarily for using the physical resources offered by the communication channel.The goal of this thesis is to provide solutions allowing autonomous and decentralized adaptation of the transmission strategies of underwater acoustic communication systems, according to the environment. To some extent, this work deals with topics that are closely related to what has motivated the first researches on cognitive radio systems. However, the specific properties of the underwater environment, the heterogeneity of interfering acoustic sources, and the absence of communication standards rise new difficulties
Jin, Xin. "Resource allocation in multicarrier cognitive radio networks." Thesis, Evry, Institut national des télécommunications, 2014. http://www.theses.fr/2014TELE0014/document.
In view of the wide usage of multicarrier modulation in wireless communications and the prominent contribution of Cognitive Radio (CR) to deal with critical shortage of spectrum resource, we focus on multicarrier based cognitive radio networks to investigate general resource allocation issues: subcarrier allocation, power allocation, routing, and beamforming in this thesis. We investigate two types of multicarrier modulation: Wavelet-based Orthogonal Frequency Division Multiplexing (WOFDM) and Fourier-based Orthogonal Frequency Division Multiplexing (OFDM). WOFDM adopts Wavelet Packet Modulation (WPM). Compared with fourier-based OFDM, wavelet-based OFDM achieves much lower side lobe in the transmitted signal. Wavelet-based OFDM excludes Cyclic Prefix (CP) which is used in fourier-based OFDM systems. Wavelet-based OFDM turns to exploit equalization to combat Inter-Symbol Interference (ISI). We evaluate the performance of WOFDM under different channel conditions. We compare the performance of wavelet-based OFDM using equalization in the time domain to that of fourier-based OFDM with CP and the equalization in the frequency domain
Sabra, Amani. "Les relations de causalité en arabe et en français avec une constitution de ressources linguistiques utilisables par l’informatique." Thesis, Paris 4, 2012. http://www.theses.fr/2012PA040239.
This thesis proposes a contrastive analysis of causality in Arabic and French. The interest of such study is twofold. We present a linguistic framework for the analysis of different linguistic causal manifestations. Then, we establish linguistic resources of causality following the contextual exploration method (Desclés 1997) used in automatic processingfor information retrieval. We turn to the study of the verbal lexicon to organize a wide variety of existing indicators verbsof causality in Arabic, and to compile a fairly complete list of the meanings of verbs indicators listed and classify them into semantic categories. In order to develop a causal semantic map, we have been obliged to specify a network of theoretical concepts related to causality. Talmy model was our starting point; it allowed us to undertake a certain decomposition of the meaning of causal indicators verbs. The model of Applicative and Cognitive Grammar (Desclés 1990) provided us with a relevant theoretical framework to analyze this decomposition. Finally, we have developed semantic-cognitive patterns for the causal indicators verbs as well as aspectual-temporal patterns taking into account the arguments involved by in the causality
Tournier, Isabelle. "Adaptation Cognitive et Vieillissement : entre Automatisme et Flexibilité." Thesis, Bordeaux 2, 2010. http://www.theses.fr/2010BOR21785/document.
The aim of this thesis is to investigate the changes in automatic and controlled processes during aging which are necessary for satisfactory daily cognitive adaptation. The focus is the impact of various cognitive variables (i.e., working memory, speed of processing and vocabulary) and preferences for routines on the expression of this possible age effect. Simple (Experiment 1) and alternating fluency tasks (Experiments 2 and 3) as well as a simple (Experiments 5a and 6a) and alternating version of the Hayling task (Experiments 5b and 6b) were administered to young adults (18-30 years old), older adults (60-74 years old) and older-old adults (75 years old and over). These tasks allowed the study of automatic processes through spreading activation in semantic memory and of controlled processes through inhibition and flexibility. The cerebral activity associated with simple and alternating fluency task execution was investigated in elderly adults with near-infrared spectroscopy (Experiment 4). The results suggest a decrease with age in the efficiency of controlled processes whereas the efficiency of automatic processes seems to be preserved. Thus, compensation based on automatic processes and accumulated knowledge may appear during aging
Drechsler, Michèle. "Les pratiques du socialbookmarking dans le domaine de l'éducation : affordances sémantiques, socio-cognitives et formatives." Thesis, Metz, 2009. http://www.theses.fr/2009METZ018L/document.
The web has become participatory and new practices of categorization of information are emerging, based on the communities of interest in social strategies of indexing numerical resources on line and produsage characterized by the production of collaborative contents by users (A. Bruns). The new approaches hightlight a new organization of knowledge sharing. This research studies the practice of sharing knowledge in the web with socialbookmarking in the field of education. Educational resources are at the heart of the teachers' s profession and the digital resources must be defined. We make an instrumental approach of digital resources within the theory of activity. A semantic approach of social indexing with the analyse of 10 000 educational resources allows us to establish its potentialities and its limits and we try to draw a provisional ontology in the field of education. We support in the Engeström's and the study of different virtual communities of practice in socialbookmarking allow us to define the various activities for the digital taggers and resources' s users. We determine the tensions between «producers» and «consumer» of resources, the legality of knowledge and experts and amators, the dynamic raised between the members. Building on the learning theories, we show that these environments are privileged spaces of «personal knowledge management», and development of professional skills
Louchart, Arthur. "Nonlinear impairments aware resource allocation for cognitive satellite systems." Electronic Thesis or Diss., Institut polytechnique de Paris, 2021. http://www.theses.fr/2021IPPAT031.
This thesis addresses the problem of resource allocation for cognitive satellite communications.In a context of increasing throughput demands, satellite communication systems are required to use frequencies already used by terrestrial systems. The underlay cognitive radio paradigm allows a secondary network to use the same frequency band that a primary network uses. However, the interference created by the secondary network must not exceed a certain limit, which is set by the primary network.We consider a cognitive satellite communication system, where terrestrial users transmit information to a satellite, and that satellite sends it back to a terrestrial gateway in a relay-like fashion.In this way, the terrestrial users of the satellite secondary network generate interference on the primary network, which is due to the secondary lobes of the transmitting antennas. The management of the transmission power of the secondary satellite users becomes essential to limit the interference on the primary terrestrial network and, at the same time, to reach the maximum throughput of the system. Moreover, taking into account the nonlinearities coming from the satellite, especially the high-power amplifier, becomes crucial when the satellite is used at its maximum capabilities.This is because the non-linear effects produced by the amplifier, modeled by Volterra series, degrade the system throughput.In this context, the thesis consists in proposing resource allocation algorithms in order to optimize the sum-rate of the satellite system, while respecting the interference limits set by the primary terrestrial network, taking into account the nonlinear effects generated by the satellite components
Aroua, Sabrine. "Spectrum resource assignment in cognitive radio sensor networks for smart grids." Thesis, La Rochelle, 2018. http://www.theses.fr/2018LAROS007/document.
With the advances in wireless communication technologies, cognitive radio sensor networks (CRSNs) stand as an efficient spectrum solution in the development of intelligent electrical power networks, the smart grids. The cognitive radio (CR) technology provides the sensors with the ability to use the temporally available licensed spectrum in order to escape the unlicensed spectrum resource scarcity problem. In this context, several challenging communication issues face the CRSN deployment for smart grids such as the coexistence of different electrical applications and the heterogeneous opportunities to access available licensed channels between smart grid sensors. The work conducted in this thesis focuses on spectrum resource allocations for CRSNs in smart grids. We concentrate our efforts on the development of new spectrum resource sharing paradigms for CRSNs in smart grids. The developed solutions focus on distributed and balanced spectrum sharing among smart grid sensors and on eventual CRSN deployment scenarios in smart grid areas. All along the thesis, channels are assigned without relying on a predefined common control channel (CCC) to exchange control messages before each spectrum access trial. All along the thesis, channels are assigned without relying on a predefined common control channel (CCC) to exchange control messages before each spectrum access trial. Performance evaluation of the different proposed channel assignment solutions shows their ability to achieve a distributed and fair opportunistic spectrum assignment in a way to consider different smart grid system characteristics
Gautier, Tatiana. "Estimation du temps et attention chez le jeune enfant : le rôle du développement des ressources attentionnelles et du contrôle de l'attention sur le processus de traitement de l'information temporelle." Clermont-Ferrand 2, 2002. http://www.theses.fr/2002CLF20003.
Salman, Rami al [Verfasser], Christian [Akademischer Betreuer] Freksa, and Christian S. [Akademischer Betreuer] Jensen. "Qualitative Spatial Query Processing : Towards Cognitive Geographic Information Systems [[Elektronische Ressource]] / Rami Al-Salman. Gutachter: Christian Freksa ; Christian S. Jensen. Betreuer: Christian Freksa." Bremen : Staats- und Universitätsbibliothek Bremen, 2014. http://d-nb.info/1072226618/34.
Tousignant, Béatrice. "La cognition sociale à l'adolescenceh[ressource électronique] : aspects comportementaux, cliniques et cérébraux." Doctoral thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/28278.
Social cognition refers to a set of cognitive functions specialized in the processing of social stimuli, allowing us to interact adequately with others. Adolescence is a developmental stage in which these cognitive functions are particularly solicited, as social relationships increase in importance and complexity. It is also a time when hormonal and brain changes are very likely to modulate cognitive functioning. However, very little is known about the ability to decode and interpret social information at this age, and even less about how brain damage can alter these functions. Thus, the main objective of this thesis was to better understand the functioning of social cognition in adolescence by examining it from various angles. Using neuropsychological measures, the first study was able to demonstrate a lower capacity to recognize emotional facial expressions in adolescents compared to adults, but a similar ability to put oneself in the perspective of a character and infer various mental states. Paradoxically, a self-reported empathy questionnaire revealed a lower tendency to take the perspective of others in adolescents, overall suggesting a possible distinction between the ability to put oneself in the place of others when measured directly and the propensity to do so in real life. The second study then demonstrated that a moderate or severe traumatic brain injury sustained during adolescence further alters this tendency to take the perspective of others in everyday life, as reported in the empathy questionnaire. The third study therefore used an experimental paradigm that is closer to real-life social interactions and examined, through functional neuroimaging, the empathic response of adolescents and adults towards social exclusion. The results showed that in such a context, adolescents are less likely to take the perspective of others, to feel their distress, and to act prosocially. The data of this thesis can thus be integrated into a detailed picture of social cognition in adolescence by specifying the functions that appear developed, those that are not fully developed, and those that are most likely to be compromised by a brain injury. Beyond these findings, the thesis has also highlighted a lower tendency to use these cognitive resources in a context where other peers are present. Ultimately, the results emphasize the importance of intervening on social cognition at this age, both in adolescents with normal development and those whose development can be compromised by brain damage.
Drechsler, Michèle. "Les pratiques du socialbookmarking dans le domaine de l'éducation : affordances sémantiques, socio-cognitives et formatives." Electronic Thesis or Diss., Metz, 2009. http://www.theses.fr/2009METZ018L.
The web has become participatory and new practices of categorization of information are emerging, based on the communities of interest in social strategies of indexing numerical resources on line and produsage characterized by the production of collaborative contents by users (A. Bruns). The new approaches hightlight a new organization of knowledge sharing. This research studies the practice of sharing knowledge in the web with socialbookmarking in the field of education. Educational resources are at the heart of the teachers' s profession and the digital resources must be defined. We make an instrumental approach of digital resources within the theory of activity. A semantic approach of social indexing with the analyse of 10 000 educational resources allows us to establish its potentialities and its limits and we try to draw a provisional ontology in the field of education. We support in the Engeström's and the study of different virtual communities of practice in socialbookmarking allow us to define the various activities for the digital taggers and resources' s users. We determine the tensions between «producers» and «consumer» of resources, the legality of knowledge and experts and amators, the dynamic raised between the members. Building on the learning theories, we show that these environments are privileged spaces of «personal knowledge management», and development of professional skills
Zhang, Haijian. "Filter Bank based MultiCarrier (FBMC) for Cognitive Radio Systems." Thesis, Paris, CNAM, 2010. http://www.theses.fr/2010CNAM0763/document.
Cognitive Radio (CR) is a fully reconfigurable radio that can intelligently change its communicationvariables in response to network and user demands. The ultimate goal of CR is to allowthe Secondary User (SU) to utilize the available spectrum resource on a non-interfering basis to thePrimary User (PU) by sensing the existence of spectrum holes. Therefore, the detection of PU isone of the main challenges in the development of the CR technology. Moreover, compared to conventionalwireless communication systems, CR system poses new challenges to Resource Allocation(RA) problems because of the Cross-Channel Interference (CCI) from the adjacent channels used bySU to PU. In the CR context, most past efforts have been spent on Orthogonal Frequency DivisionMultiplexing (OFDM) based CR systems. However, OFDM technique exhibits some shortcomingsin application due to its significant spectrum leakage. Filter Bank based Multi-Carrier (FBMC), asanother promising Multi-Carrier Modulation (MCM) candidate, has been recently proposed for CRapplications. In this dissertation, three important issues in developing a FBMC based CR system arediscussed.The three prime issues can be summarized: we firstly survey the spectrum sensing problemsof OFDM and FBMC signals by using Cyclostationary Signature (CS) detector. Furthermore, wepropose a Polyphase Filter Bank (PFB) based multi-band sensing architecture, and argue for its advantage;secondly, the comparison of OFDM and FBMC from the spectral efficiency point of viewis discussed; and lastly, our emphasis is placed on the strategic resource allocation algorithms fornon-cooperative multi-cell CR systems.The overall proposed algorithms have been verified by simulation. Numerical results show thatFBMC, as opposed to OFDM, could achieve higher spectrum efficiency and attractive benefit inspectrum sensing. The contributions of this dissertation have heighten the interest in applying FBMCin the future CR systems
Dieler, Alica Christina [Verfasser], and Andreas [Akademischer Betreuer] Fallgatter. "Investigation of variables influencing cognitive inhibition[[Elektronische Ressource]] : from the behavioral to the molecular level = Untersuchung der Einflussgrößen kognitiver Unterdrückung / Alica Christina Dieler. Betreuer: Andreas Fallgatter." Würzburg : Universitätsbibliothek der Universität Würzburg, 2011. http://d-nb.info/101704290X/34.
Boudjema, Cédric. "La fonction éducative des musées dans la société numérique : analyse comparative de l'offre pédagogique en ligne de huit musées nationaux dans quatre pays (France, Angleterre, Australie, Etats-Unis)." Thesis, Lille 3, 2016. http://www.theses.fr/2016LIL30013/document.
This research studies museum internet sites and in particular the pedagogy of eight national institutions in four different countries and suggests that online museums are educational content players.The interest is to investigate the educational content of the internet sites using a content analysis and implementing a comparison between the four countries and the types of internet sites to be able to understand the practices – and especially what Jean Davallon calls « the anticipation by the “sender” » that the visitor will engage in (the sender aiming for example to keep the attention of the latter or to provide guidance in the contents), the typology of content and the teaching strategies put in place by the online museum institutions. The online educational offer is defined here as a permanent activity as a source of building knowledge, consultation, criticism, and entertainment, from the museum resources. This offer is also constructed according to the consistent rules of Web design.We have chosen to study the online pedagogy according to a constructivist approach that drives us to privilege certain key concepts : individual learning ways, learning processes, cognitive strategies, meta-cognitive strategies, {learning styles}, taxonomy. From a methodological point of view, this thesis relies on a qualitative approach and privileges a content analysis from an analysis grid with eleven categories : the corpus is composed of eight internet sites and of two types of national museums : the art museums and the science museums with an educational section. The thesis is composed of two tomes. The tome 2 contains the complete analysis of the sites and the tome 1 includes three parts. In the first part, the research discusses the educational role of museums with its specificities and complexities. This part defines the historical context of the educational function of museums that very early on developed an educational strategy for the public. It also shows the specificity of museums in informal education as a place of learning concepts and development that develop two types of mediation. The museum favours the formulation of questions; it orientates reflexion and raises questions. It then shows the museum as an important partner and complementary to school. Finally, this part precises the historical context of online museums of the four countries from our analysis and the progressive development of the cultural policies of the present and the progressive actions put into place by the museums.Secondly, the research focuses on the thematic analysis of the internet sites and on their educational sections and attempts to show the successive steps of the content analysis via the analysis grid constructed for this research. Firstly, it is about showing the ergonomics of the sites to progressively arrive upon the general treatment of the educational sections of the sites, that is to say to identify the mechanisms of underlying internet sites and of their educational sections and secondly to identify the differences between the types of museums and their countries. Finally, the third part of the research attaches importance to the typology of the online educational content and focuses on the strategies put into place in the sites as well as the pedagogy deployed. The internet sites are thus viewed as interconnected elements, intended for a target audience and reinforcing the social role of the museum. The schools and the teaching body are a privileged population; a prominent place for them is underlined
Thuaire, Flavien. "Les processus d'évaluation et de régulation de l'apprentissage : psychopathologie cognitive de la schizophrénie et études préliminaires auprès de participants sains." Thesis, Clermont-Ferrand 2, 2013. http://www.theses.fr/2013CLF20026/document.
Schizophrenia is characterized by a range of positive and negative symptoms and bycognitive deficits including the most disabling one, memory. Metamemory, which is knowledge about memory is of particular interest for the understanding and remediation of this trouble. It involves a monitoring and a control process, which would be in interaction.Previous studies have shown that monitoring is spared whereas control is impaired. However,these relations between these processes have not been examined whereas they could compensate for memory deficit. The aims of this work were to observe these relations between monitoring and control in schizophrenia and cognitive resources linked to these processes on the one hand. On the other hand, we wished to observe the use of different kinds of materials and learning strategies in healthy participants to get better fundamental knowledge about metamemory. Two experiments showed that patients were able to use monitoring to adapt their learning strategy and also that their memory deficits were linked too ther cognitive functions. Five following experiments confirmed that healthy participants do not use intrinsic and extrinsic characteristics of the materials in the same way when makin gjudgments and using strategies. These data are discussed and point out that more research about metamemory in schizophrenia is of interest for the remediation of memory deficits inschizophrenia patients
Roche, Lionel. "Analyse de l'activité d'étudiants en Licence STAPS dans le cadre d'un dispositif de vidéo-formation : conception et usage de ressources pour la professionnalisation au métier d'enseignant d'Education Physique et Sportive." Thesis, Université Clermont Auvergne (2017-2020), 2017. http://www.theses.fr/2017CLFAL028/document.
This thesis is part of the empirical and technological research program of the "course of action" (Theureau, 1992) in cognitive anthropology. She is studying the design, use and effects of a collective video-training device for undergraduate students in Physical Education to develop their ability to analyze and understand classroom situations in Physical Education. Two aims are pursued: a) an epistemic aim seeking to better understand the forms of activity and experience deployed by students in a video-training situation and b) a technological design aim of the "activity-oriented" video-training device and responding to a design in use process. The study was conducted with a group of students (n = 15) enrolled in a pre-professionalization course in the third year degree in Physical Education Teacher Education. Five types of data were collected during the device based on periods of internships and workshop at University: (i) video recording data of student's classroom activity during the internship and also during workshop, (ii) written records produced by students during internship and workshop, (iii) self-confrontation interview data on their activity in classroom and (iv) in their written records, and (v) quantitative and qualitative data from surveys. The results reveal (i) students' appropriation of a grid allowing them to analyze PE lesson and to analyze the key moments, (ii) a lived experience in video-training which reflects a reflexive inclination on pedagogical face-to-face moments in the PE lesson, (iii) four typical forms of classroom video analysis (describe, judge, interpret, project), evidence of teacher-centered observation activity in classroom as a manager, and a blindness to student motor learning activity; (iv) the role of peers as an accelerator of the ability to analyze class practices. These results relating to the activity of students in training made it possible to jointly consider the design of different phases of the system, finalized by a first online training platform "Former à l’intervention en EPS" (Roche & Gal-Petitfaux, 2014a), then a second "Observation e tRégul@tion en EPS" (Roche & Gal-Petitfaux, 2016)
Ta, Duc-Tuyen. "Channel Surveillance Strategy and Interference Reduction in Future Wireless Networks." Electronic Thesis or Diss., Paris, ENST, 2018. http://www.theses.fr/2018ENST0039.
The wireless revolution is creating a huge demand for accessing to the radio frequency spectrum with the explosion of the number of connected devices and the large diversity of use cases and requirements. However, the conflict between the spectrum scarcity and the spectrum underutilization leads to significant inefficiencies of wireless communications and impedes the deployment of new applications.Recently, Cognitive Radio (CR) has emerged as a promising technology to address to alleviate the spectrum scarcity and better utilize the spectrum resources by enabling the network users to detect and exploit the spectrum opportunities. The successful deployment of CR networks, however, depends not only on the efficient exploitation of the spectrum opportunities but also on the self-coexistence mechanisms between cognitive users (SUs). The objective of this thesis, therefore, is to provide a systematic study of self-coexistence mechanisms for the cognitive users in both centralized and distributed CR network architecture, which directly address the unaddressed technical challenges of the threat caused by the misbehaving users in the centralized infrastructure networks and the resource allocation issues in the distributed infrastructure networks
Zhang, Haijian. "Utilisation des modulations multiporteuses à base de bancs de filtres pour l'application à la radio cognitive." Phd thesis, Conservatoire national des arts et metiers - CNAM, 2010. http://tel.archives-ouvertes.fr/tel-00628956.
Berrada, Ward Laila. "Contribution à la détermination des fondements théoriques des indicateurs de gestion des ressources humaines : une illustration à partir du cas des entreprises marocaines." Thesis, Angers, 2015. http://www.theses.fr/2015ANGE0091.
This doctoral research focuses on the construction of Human Resource Management (HRM) tools foundations and more specifically the design of management indicators. Our literature review confirms a predominance of rationality in the design of Human Resource (HR) indicators and we wanted to go further to find more explanations for such dominance. In this perspective, we have adopted a multi-paradigmatic approach. In addition to the rational framework, two other paradigms were also mobilized: Cognitive and Conventionalist paradigms. After having highlighted the arguments justifying the significance of rationality in the design of HR indicators, we expanded our analysis. Instead of rationality in decision making, the contribution of emotions in enhancing the rationality and logical use of HR indicators to achieve performance was enforced. This expansion has allowed us to open up to other theoretical approaches, the analysis did not cause a breaking with rationality but rather it’s strengthening. Thus, we sought to identify the arguments brought by the cognitive paradigms and conventionalist to support this predominance of rationality. The exploration of these different conceptual frameworks, allowed us to formulate our research questions and to mobilize a qualitative approach based on a multi-case method. Our empirical results, limited to Moroccan companies, confirm the importance of rationality in the design of HR indicators and highlight explanations that remain largely consistent with our theoretical frameworks
Boulon, Joline. "Rôle et statut de la sensibilisation linguistique sur multimédia dans l'enseignement de l'anglais dispensé à des étudiants spécialistes d'autres disciplines. Analyse et pratique des notions linguistiques en anglais chez les étudiants scientifiques." Phd thesis, Université Jean Moulin - Lyon III, 1999. http://tel.archives-ouvertes.fr/edutice-00000315.