Дисертації з теми "Mesures active"
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Ravaioli, Riccardo. "Inférence active de la neutralité des réseaux." Thesis, Nice, 2016. http://www.theses.fr/2016NICE4044/document.
In the last decade, some ISPs have been reported to discriminate againstspecific user traffic, especially if generated by bandwidth-hungry applications(e.g., peer-to-peer, video streaming) or competing services (e.g. Voice-over-IP).Network neutrality, a design principle according to which a network shouldtreat all incoming packets equally, has been widely debated ever since. In thisthesis we present ChkDiff, a novel tool for the detection of trafficdifferentiation at the Internet access. In contrast to existing work, our methodis agnostic to both the applications being tested and the shaping mechanismsdeployed by an ISP. The experiment comprises two parts, in which we check fordifferentiation separately on upstream and downstream traffic that wepreviously dump directly from the user. In the upstream direction, ChkDiffreplays the user's outgoing traffic with a modified TTL value in order to checkfor differentiation on routers at the first few hops from the user. By comparingthe resulting delays and losses of flows that traversed the same routers, andanalyzing the behaviour on the immediate router topology spawning from theuser end point, we manage to detect instances of traffic shaping and attempt tolocalize shapers. Our study on the responsiveness of routers to TTL-limitedprobes consolidates our choice of measurements in the upstream experiment.In the downstream experiment, we replay the user's incoming traffic from ameasurement server and analyze per-flow one-way delays and losses, whiletaking into account the possibility of multiple paths between the two endpoints.Along the chapters of this thesis, we provide a detailed description of ourmethodology and a validation of our tool
Amiel, Stéphane. "Mesures de température de surface des composants face au plasma dans les Tokamaks." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM4736/document.
During this PhD, the challenges on the non-intrusive surface temperature measurements of metallic plasma facing components in tokamaks are reported. Indeed, a precise material emissivity value is needed for classical infrared methods and the environment contribution has to be known particularly for low emissivities materials. Although methods have been developed to overcome these issues, they have been implemented solely for dedicated experiments. In any case, none of these methods are suitable for surface temperature measurement in tokamaks.The active pyrometry introduced in this study allows surface temperature measurements independently of reflected flux and emissivities using pulsed and modulated photothermal effect. This method has been validated in laboratory on metallic materials with reflected fluxes for pulsed and modulated modes. This experimental validation is coupled with a surface temperature variation induced by photothermal effect and temporal signal evolvement modelling in order to optimize both the heating source characteristics and the data acquisition and treatment. The experimental results have been used to determine the application range in temperature and detection wavelengths.In this context, the design of an active pyrometry system on tokamak has been completed, based on a bicolor camera for a thermography application in metallic (or low emissivity) environment.The active pyrometry method introduced in this study is a complementary technique of classical infrared methods used for thermography in tokamak environment which allows performing local and 2D surface temperature measurements independently of reflected fluxes and emissivities
Antoni, Rodolphe. "Optimisation des mesures d'interrogation neutronique active par couplage d'une méthode de correction des effets de matrice." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENY014.
The fissile mass in radioactive waste drums filled with compacted metallic residues (spent fuel hulls and nozzles) produced at AREVA La Hague reprocessing plant is measured by neutron interrogation with the Differential Die-away measurement Technique, on the waste compaction facility (ACC). In the future, old hulls and nozzles mixed with ion-exchange resins will be measured. The ion-exchange resins increase neutron moderation in the matrix, compared to the waste measured in the current process. In this context, a matrix effect correction method based on a drum monitor (3He proportional counter) has been studied. The feasibility of the method was first performed with the R&D measurement cell PROMETHEE 6, showing a good correlation between the monitor signal and the matrix effect correction, and the capability of MCNP simulations to reproduce experiments and to estimate the performances of the proposed correction. Therefore, the industrial implementation of the method and the assessment of its final performances have been studied by numerical simulation. Calculations demonstrate that the method allows keeping the highest error on the measured fissile mass below roughly a factor of 2, while the matrix effect without correction ranges on 2 orders of magnitude. In addition, the analysis of experimental data from the current process shows a good correlation between known physical properties of the matrix (moderation and absorption) and the monitor signal, demonstrating the reliability of the proposed approach. According to these satisfactory results, this correction method will be implemented on the industrial station. More generally, this method could be applied to similar waste measurement systems
Antivilo, Osvaldo. "Les hydrocarbures aromatiques en milieu urbain : mesures et impact sur la chimie atmosphérique." Paris 7, 2001. http://www.theses.fr/2001PA077249.
Ruch, Olivier. "Reconnaissance des formes par Contour Actif Statistique - Application à l'imagerie optronique active." Aix-Marseille 3, 2001. http://www.theses.fr/2001AIX30058.
Active systems allow image acquisition both during day and night, with a highest resolution than the infra-red equipments do. Nevertheless, the main drawback of these systems compared to the classical optical sensors is that the obtained images are strongly corruptedby the speckle effect, and therefore their automatic interpretation is drastically limited. In this thesis, we propose to study in which way the Statistical Polygonal Snake (SPS) can be used in orderto perform the recognition of objects in speckled images. The recognition method which has been considered is the nearest neighbour algorithm; we select the reference which is the most similar to the silhouette obtained with the SPS by evaluating a given similarity function between contours
Navello, Lorris. "Développement d’un pyromètre bichromatique impulsionnel pour mesures de températures de surfaces solides et liquides en milieux perturbés." Thesis, Paris 10, 2015. http://www.theses.fr/2015PA100143/document.
Optical passive methods of temperature measurements such as thermography or optical pyrometry are very interesting because they allow a non-intrusive measurement with the target object provided to know the emission factor. The knowledge of this factor is critical for determining the actual temperature of a surface from the thermal radiation emitted in a wavelength band. The bichromatic pulsed pyrometer allows to overcome the knowledge of this parameter provided that precautions are taken in the choice of the values of wavelengths. When the object to be measured is placed in industrial environments, such passive optical methods are greatly disturbed by the presence of an optically absorbing medium. It is also distorted for objects located in very hot environments emitting intense interfering radiation. In this thesis, we present an active bichromatic radiometric method for measuring the temperature of a surface in harsh environments. The method is based on a localized excitation by a modulated laser source in the infrared range. Detecting the temperature range which is correlated with the excitation allows a synchronous detection to extract the signal embedded in a noise up to 106 times superior. Working at short wavelengths (visible range and near infrared range) offers a large dynamic range and minimizes the error due to variations in emissivity with the wavelength. This system collects the radiation emitted by the object at a distance from a few meters up to dozens of meters depending on the configuration of the optical system. The principle of the measurement method, the optical wavelength separation system and the telemetry apparatus are presented in this report as well as the theoretical and experimental study of the sensitivity of the device, its calibration and the results obtained in different industrial sites
Cioranesco, Jean-Michel. "Nouvelles Contre-Mesures pour la Protection de Circuits Intégrés." Thesis, Paris 1, 2014. http://www.theses.fr/2014PA010022/document.
Embedded security applications are diverse and at the center of all personal embedded applications. They introduced an obvious need for data confidentiality and security in general. Invasive attacks on hardware have always been part of the industrial scene. The aim of this thesis is to propose new solutions in order to protect embedded circuits against some physical attacks described above. ln a first part of the manuscript, we detail the techniques used to achieve side-channel, invasive attacks and reverse engineering. I could implement several of these attacks during my thesis research, they will be detailed extensively. ln the second part we propose different hardware countermeasures against side-channel attacks. The third part is dedicated to protection strategies against invasive attacks using active shielding and we conclude this work by proposing an innovative cryptographic shield which is faulty and dpa resistant
Loche, Florence. "Contrôle des déchets radioactifs et couplage de mesures neutron/gamma : exploitation de la capture radiative pour corriger les effets de matrice pénalisant la mesure de la masse fissile par interrogation neutronique active." Grenoble INPG, 2006. http://www.theses.fr/2006INPG0116.
Ln the framework of radioactive waste drums control, difficulties arise in the non-destructive measurement of fissile mass 235U, 239PU. . . ) by Active Neutron Interrogation (ANI), when dealing with matrices containing materials (CI, H. . . ) influencing the neutron flux. The idea is to use the neutron capture reaction (n,y) to determine the matrix composition to adjust the ANI calibration coefficient value. This study, dealing with 118 litres, homogeneous drums of density less than 0,4 and composed of chlorinated and/or hydrogenated materials, leads to build abacus linking the y-ray peak areas to the ANI calibration coefficient. Validation assays ofthese abacus show a very good agreement between the corrected and true fissile masses for hydrogenated matrices (max. Relative standard deviation: 23 %) and quite good for chlorinated and hydrogenated matrices (58 %). The developed correction method improves the measured values. It may be extended to 0,45 density, heterogeneous drums
Jacquier, Philippe. "Vers des mesures précises de violation de la parité dans le Césium : Contruction d'une expérience nouvelle utilisant une détection active par émission induite." Phd thesis, Université Pierre et Marie Curie - Paris VI, 1991. http://tel.archives-ouvertes.fr/tel-00011878.
Jacquier, Philippe. "Vers des mesures precises de violation de la parite dans le cesium : construction d'une experience nouvelle utilisant une detection active par emission induite." Paris 6, 1991. http://www.theses.fr/1991PA066167.
FEBVRE, GUY. "Etude des proprietes des cirrus et des trainees de condensation au moyen de mesures in situ et par teledetection active (lidar) et passive (radiometrie)." Clermont-Ferrand 2, 1994. http://www.theses.fr/1994CLF21636.
Ravelomanana, Sahobimaholy. "Gestion de réseaux et de systèmes : surveillance active par une approche MDA." Toulouse 3, 2009. http://www.theses.fr/2009TOU30127.
The complexity of communications infrastructure requires active management (knowledge of health of interdependent resources) masking the heterogeneity of underlying components. Faced with this increasing complexity of managed systems, the solutions for managing networks and services tend to automate the execution of control loop Monitoring / Analysis / Planning / Execution and enrichment of knowledge management. Given this context, we worked on the implementation of an Active monitoring (Monitoring / Analysis) based on standard response to the heterogeneity and interdependence of systems. Based on an MDA approach, we defined a methodology in order to represent the informational knowledge management regardless of platform supports this management. We have coupled the CIM meta-model of the Distributed Management Task Force and state chart diagram of UML 2. 0 in order to allow the capitalization of a unified knowledge base representing the non-functional views of observed systems. We also specified a generic architecture to support these models including functional components of active monitoring. This architecture offers integration capabilities and detection of changes in the behavior of components of observed system. We tested this approach in two application contexts: a heterogeneous avionics network and a large scale grid computing. The results showed: (1) benefits of capitalization of management knowledge modeling through specification and reuse of PIM models, (2) reduction of development time by taking into account automatically models into an execution platform (3) the ability and interest of integration for global and open monitoring (4) good performance of the implementation of the active monitoring
Arsalane, Nabil. "Channel Emulation for active characterization of MIMO communication systems." Thesis, Limoges, 2014. http://www.theses.fr/2014LIMO0069/document.
This thesis is part of the field of the characterization of wireless communication systems using antennas diversity. Indeed, such systems allow fighting against the signals fading, when the terminal is inside a strong multipath environment. The issue of such research is: to study the association of multiple antennas at transmitting and/or receiving sides to improve the link budget, and the capacity of wireless systems, (decrease of BER (Bit Error Rate), increase of throughput …). This thesis takes an interest to the electromagnetic aspect, and signal processing. In order to understand the involved phenomena, and to characterize the terminal performance, it should be placed in a controlled multipath propagation environment in time, and in space. This brings us to find measurement methodologies able to reproduce models of realistic propagation channels. As part of this thesis the method used is the reverberation chamber. In this thesis we are interested in the time aspect. Reverberation chamber (RC) is considered as a useful tool to emulate rich multipath environments. In this contribution, this device is employed to emulate multi clusters channel models (cluster is defined as a group of multipath), and evaluate performance of wireless communication systems. This evaluation is performed with real time and not-real time measurements. It remains to note that among the objectives set out in this PhD thesis is to obtain electromagnetic simulation model of the reverberation chamber based on circuit approach, in order to determine the channel transfer function versus losses quantities
Baudry, Guillaume. "Correction des effets de matrice par spectrométrie des rayonnements gamma de capture : application à la mesure par Interrogation Neutronique Active (I.N.A.)." Phd thesis, Université Louis Pasteur - Strasbourg I, 2003. http://tel.archives-ouvertes.fr/tel-00390689.
Tlaiss, Ziad. "Automated network packet traces analysis methods for fault recognition and TCP flavor identification." Electronic Thesis or Diss., Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2023. http://www.theses.fr/2023IMTA0384.
In recent years, the field of network troubleshooting has garnered significant attention from researchers due to the complexity and importance of this task. The work presented in this thesis focuses on automating network troubleshooting using performance metrics extracted from packet captures. The first contribution of this thesis lies in extracting features to identify the root cause of an anomaly by analyzing TCP packet traces with bad performance. We have categorized four frequently observed causes of degradation: transmission problems, congestion problems, jitter problems, and application-limited problems. The second contribution of this thesis involves developing an automated method to detect the moment of exiting the Slow-Start state. The significance of this method lies in saving valuable time in the analysis of network degradation, as the Slow-Start state serves as a key indicator for fault diagnosis. The third contribution of this thesis revolves around identifying the BBR congestion control algorithm. The primary goal of our approach is to detect whether packet pacing is employed in a TCP connection. This method relies on modeling the distribution of inter-packet duration during the Slow-Start state. The objective is to distinguish unimodal distributions of inter-packet intervals in the case of BBR compared to mixed two component distributions in the case of CUBIC
Keo, Sam Ang. "Développement d'une méthode de thermographie infrarouge active par excitation micro-ondes appliquée au contrôle non destructif." Thesis, Artois, 2013. http://www.theses.fr/2013ARTO0214/document.
In the field of Civil Engineering, many inspection methods have been developed. They are intended to evaluate the condition of structures by providing information about the internal structure or status of the materials. Techniques based on infrared thermography are promising as they have the advantage of giving high performances and results by the thermograms observation that seems more accessible. The objective of the thesis is to develop a new active infrared thermography method based on a microwave excitation system designed and built for this study.The microwave source was set up based on a commercial magnetron 800 W at2.45 GHz associated to a pyramidal horn antenna for guiding microwave radiation to the heated elements. Compared to other sources traditionally used in active infrared thermography, the microwaves can propagate into the volume of a concrete element. The waves undergo the reflection and the diffraction effects while they impact any metal parts. The interference phenomena can appear on the surface and generate, by the radiothermal effect, the temperature gradients observed by infrared thermography. These effects occur instantaneously. Considering all the safety, the tests with the new excitation system were carried out in a high frequency protection cell. This new method has been applied to the defect detection (adhesive absence) in the case of a composite reinforcement (CFRP), a metal element behind a wooden plate of one centimeter of thickness, and more particularly the vertical reinforcement bars in a reinforced concrete wall
Zouinkhi, Ahmed. "Contribution à la modélisation de produit actif communicant : spécification et évaluation d'un protocole de communication orienté sécurité des produits." Thesis, Nancy 1, 2011. http://www.theses.fr/2011NAN10010/document.
Monitoring of chemical product storage is a delicate operation in the sense that it requires knowledge of the nature of each stored product, their location, their interaction and possible actions to be implemented in case of emergency. To facilitate the storage management, this thesis proposes to use the concept of ambient where the product has its own information system and wireless communication so as to make it intelligent and autonomous. This thesis proposes and develops a model of internal behavior of active product that allows a distributed approach of active security. This can lead to a communication protocol of application level to embed the active products. This protocol is formally assessed using hierarchical colored Petri nets. Finally, this protocol is implemented in the simulator Castalia/Omnet++ to analyze it in several scenarios and also for the experience when going to scale. The results show the usefulness and feasibility of the concept of active product
Zhou, Mengxi. "CEM des implants cardiaques aux basses fréquences 50 Hz dans un contexte normatif." Electronic Thesis or Diss., Université de Lorraine, 2023. http://www.theses.fr/2023LORR0110.
Targeting cardiology diagnosis and treatment, active implantable medical devices (AIMDs) have been rapidly developed and widely applied with constantly updated technologies in recent decades. It is vital for scientific research to catch up with the speed of the information era in terms of the side effects on human beings and the environment. Pacemakers (PMs), used for the treatment of arrhythmias (bradycardias and tachycardias), and implantable cardioverter defibrillators (ICDs), for palliating serious ventricular arrhythmias by electric shocks to the myocardial tissue are important AIMDs normally implanted in the human chest. Electromagnetic radiation is inevitable present in our surroundings and raised many questions concerning the potential effects on the AIMD-wearers. The increasing number of medical implant wearers, including those in active professional activities, has led to questions regarding their performance in the presence of an occupational electromagnetic field (EMF) exposure. Since the 1960s, these questions have concerned possible interference linked to the energy transport network. The frequencies allocated to electrical energy (50 Hz and 60 Hz) are in the analysis bandwidth of the cardiac signals, of which spectrum extends from a few Hertz to approximately 150 Hz. The AIMDs are usually equipped with selective filters enabling to significantly reduce or eliminate the interference. However, considering the nature formation of the heart signals, 50 Hz and 60 Hz may not be filtered in order to ensure the cardiac signal waves are correctly and completely sensed.In the workplaces, it is inevitable to have the existence of workers who are susceptible to the electromagnetic field (EMF)-related impact. The presence of workers wearing AIMDs is then to be considered as specific cases. In other words, particular attention should be given to AIMD carriers who are subject to higher risks and corresponding risk evaluation process should be established. The procedure for assessing the EMF exposures for workers bearing AIMDs was proposed in EN 50527 to determine the risk arising from the exposures in the workplaces. Immunity test on AIMDs is critical in the risk assessment procedure and requires a simple, feasible, and risk-free test method. To date, the electric field exposures at low frequencies has received little attention yet they commonly exist in the workplaces in electrical industries, for example, area near power lines and substations. In this study, high-intensity electric field exposures are mainly concerned. The frequency band was limited to extremely low frequency at 50 Hz to focus on the occupational exposures caused by power sources.The interference can be evaluated by the estimation of the induced voltage at its input. Equivalent systems can be built up by adopting this conception to reproduce the exposures and the implantation conditions in order to generate same effects at the input of cardiac implant (same induced voltage). In this work, a theoretical and experimental study was performed on an in vitro phantom that allowed to determine the voltage induced at the input of a cardiac implant subjected to a high-intensity electric field at 50 Hz. The phantom is composed of two parts with electrical characteristics similar to those of the human heart and the chest, where the cardiac lead and the housing are implanted. Experimental measurements and numerical simulation are coherent which validates the equivalence factors we found for our systems. Thus, the in vitro phantom can be applied as an equivalent system in the workplace for the immunity test on cardiac implants. Another result we established in this study is the equivalence between an electric field exposure system and an injection system which allows us to reduce the complexity of the study, and conduct simpler tests with reproduced perturbations
Bel, Coraline. "Analysis of debris-flow occurrence in active catchments of the French Alps using monitoring stations." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAU007/document.
Flows – such as debris flows – caused by heavy rainfalls in torrents can mobilise a huge amount of sediments. When they reach the urbanised areas, they may endanger the people’s safety or cause damages. Approaches aimed at mitigating torrential risk widely rely on rainfall intensity-duration thresholds which determine the minimum debris-flow triggering conditions. However, these thresholds suffer from a high variability related not only to inter-site differences but also to the method applied to design them. In addition, they are likely to cause false prediction because the intensity and the duration of the rainfall event are not the only explanatory variables. This PhD research work aim (i) to provide a rigorous methodological framework for designing rainfall threshold in order to limit the variability sources, and (ii) to improve their performances by including both the triggering and the predisposing factors. It is supported by field observations stemming from high-frequency monitoring stations installed since 2011 on two very active debris flow-prone torrents in the French Alps: the Manival and the Réal. First, the images and data gathered between 2011 and 2016 were analysed in order to detect and characterise the sediment laden-flows. To deal with the variety of recorded flows, a phenomenological classification was performed. Second, the minimum intensity-duration threshold for debris-flow triggering was assessed. The threshold sensitivity to the rainfall event definition was estimated. Third, a logistic regression model was used to discriminate the critical rainfall events which do not lead to a debris flow. It makes it possible to select the most relevant explanatory variables. At last, several avenues of work were proposed (i) to move the knowledge of debris-flow initiation conditions from a local to a regional level, with a view to application in a warning system dedicated to hydrometeorological risks, and (ii) to improve the ability to predict, not the debris-flow triggering in the production zone, but the debris-flow propagation up to the area concerned
Zouinkhi, Ahmed. "Contribution à la modélisation de produit actif communicant : spécification et évaluation d'un protocole de communication orienté sécurité des produits." Electronic Thesis or Diss., Nancy 1, 2011. http://www.theses.fr/2011NAN10010.
Monitoring of chemical product storage is a delicate operation in the sense that it requires knowledge of the nature of each stored product, their location, their interaction and possible actions to be implemented in case of emergency. To facilitate the storage management, this thesis proposes to use the concept of ambient where the product has its own information system and wireless communication so as to make it intelligent and autonomous. This thesis proposes and develops a model of internal behavior of active product that allows a distributed approach of active security. This can lead to a communication protocol of application level to embed the active products. This protocol is formally assessed using hierarchical colored Petri nets. Finally, this protocol is implemented in the simulator Castalia/Omnet++ to analyze it in several scenarios and also for the experience when going to scale. The results show the usefulness and feasibility of the concept of active product
BOUKABARA, SID-AHMED. "Couplage des mesures hyperfrequences actives et passives." Paris 7, 1997. http://www.theses.fr/1997PA077098.
Cherif, Amina. "Sécurité des RFIDs actifs et applications." Thesis, Limoges, 2021. http://www.theses.fr/2021LIMO0015.
Over the 30 last years, active RFID devices have evolved from nodes dedicated to identification to autonomous nodes that, in addition, sense (from environment or other sources) and exchange data. Consequently, the range of their applications has rapidly grown from identification only to monitoring and real time localisation. In recent years, thanks to their advantages, the use of active RFID nodes for mobile data collection has attracted significant attention. However, in most scenarios, these nodes are unattended in an adverse environments, so data must be securely stored and transmitted to prevent attack by active adversaries: even if the nodes are captured, data confidentiality must be ensured. Furthermore, due to the scarce resources available to nodes in terms of energy, storage and/or computation, the used security solution has to be lightweight. This thesis is divided in two parts. In the first, we will study in details the evolution of active RFID nodes and their security. We will then, present, in the second part, a new serverless protocol to enable MDCs (Mobile Data Collectors), such as drones, to collect data from mobile and static Active RFID nodes and then deliver them later to an authorized third party. The whole solution ensures data confidentiality at each step (from the sensing phase, before data collection by the MDC, once data have been collected by MDC, and during final delivery) while fulfilling the lightweight requirements for the resource-limited entities involved. To assess the suitability of the protocol against the performance requirements, we will implement it on the most resource-constrained secure devices to prove its efficiency even in the worst conditions. In addition, to prove the protocol fulfills the security requirements, we will analyze it using security games and we will also formally verify it using the AVISPA and ProVerif tools
El, Alaoui Faris Moulay Driss. "Physique des membranes actives : Mesure de spectres de fluctuations." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2008. http://tel.archives-ouvertes.fr/tel-00812019.
LAVILLE, PATRICIA. "Mesure de composes gazeux tropospheriques par spectrometrie d'absorption active uv et visible." Paris 7, 1992. http://www.theses.fr/1992PA077289.
Dupont, Erwan. "Méthode de mesure tridimensionnelle active appliquée au contexte de l’analyse endoscopique ou coloscopique." Thesis, Compiègne, 2015. http://www.theses.fr/2015COMP2198/document.
This thesis aims at developing a tri-dimensional measurement endoscopic device in a double context: the first one is industrial with endoscopic inspection of mechanical pieces (tubular inspection, for example) at micrometric resolution. The second context is medical with tri-dimensional shape detection during colonoscopy to help the surgeon diagnosis. In this study, flexible endoscopy is made possible by using image guides and the tri-dimensional reconstruction method is based on active stereovision where a digital micro-mirror device is used to spatially structure the incoming light. After developing the state of the art, an optical conception and evaluation method, applied to stereovision for flexible endoscopic devices is described. The instrumental realization is then detailed and metrologically evaluated. An innovative method that allows to switch dynamically between active and passive stereovision is then detailed. Finally, 3D reconstruction algorithms adapted to this endoscopic instrument are proposed. The scientific contributions of this study are multiple. Firstly, an optical analysis method based on the modulation transfer function to design an endoscopic stereovision system is proposed. An image processing method for robust calibration in a defocused optical environment and a new phase-shifting algorithm for 3D reconstruction are proposed. Finally, a realization principle for 3D measurement in flexible endoscopy was extracted from the combination of all these methods
Bauër, Pierre. "Mesures mécaniques et génération de forces de réseaux d’actine branchés avec des micro-cylindres magnétiques." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066428/document.
The work done during this tesis concerns the mechanics and force generation processes of branched actin networks reconstructed in vitro. To study these effects, we’ve developped a new experimental setup, based on self assembly of supermaramagnetic microcylinders under a magnetic force. This allows us to obtain relations between force and growth velocity of branched actin networks, as well as linking force generation with mechanics, which are crucial to understand cell mechanics and migration
Sakhraoui, Imane. "Contribution à la surveillance d'un module d'électronique de puissance sous sollicitations actives par mesures thermiques." Thesis, Toulouse, INPT, 2018. http://www.theses.fr/2018INPT0100/document.
The current trend of integrating powerful power modules into increasingly smaller volumes. This volume leads to new problems, especially in terms of reliability : Indeed, during their operating cycles, the semiconductor switches and their surrounding environment become subject to harshful electrothermal stresses. Thus, increase of reliability of power modules induces the precise knowledge of the local temperature, even if it can not be measured at any location. The main objective of this thesis is to estimate a physical variables in a specific non measured location, using linear functional observers allowing to estimate the temperature at any point by means of measurements provided from thermal sensors located at a few precise points. The use of this observer reduce the dimension of the considered problem. In the multi-physics context, methodologies and algorithms have been developed to allow the monitoring of electrothermal behavior power electronics modules. In order to obtain observation algorithms directly, which could be implemented on a real-time embedded target such as a digital signal processor, the application of a linear observer in the discrete time framework is proposed. Consequently, it is necessary to reduce the size compared to the initial system resulting from the model, in order to limit the calculation complexity. The originality of this work consists in proposing simple design methods for minimal order linear functional observers for large complex systems. Special attention has been given to unknown input linear functional observers. Note that in case of a power electronics module, some inputs may be poorly known such as the thermal power extracted by the cooling system, or that injected by the ancillary elements of the module as chips or bonding wire. An unknown input linear functional observer allows to overcome this lack of knowledge by treating these inputs as unknown data. Note that we chose to present experimental results so as to demonstrate the practical feasibility of the proposed methods
Ruet, Laurent. "Active control and sensor noise filtering duality : application to Advanced LIGO suspensions." Lyon, INSA, 2007. http://theses.insa-lyon.fr/publication/2007ISAL0001/these.pdf.
L'étude présentée porte sur le contrôle actif des supensions pour Advanced LIGO. LIGO est un projet américain ayant pour but la détection d'ondes gravitationnelles, prédites par Einstein. Afin de mesurer ces ondes, le bruit sismique dot être atténué par un facteur de plusieurs milliards. Le dernier étage du système d'isolation sismique est un pendule filtrant le bruit sismique à hautes fréquences. Ce pendule présente d'importantes résonances à basses fréquences qui sont amorties par contrôle actif. Toutefois, ce contrôle re-injecte le bruit de mesure et détériore les performances d'isolation du pendule. La problématique est donc de concevoir une boucle de contrôle qui amortie les résonances tout en minimisant la réinjection du bruit de mesure à hautes fréquences. L'association d'un contrôle modal et d'un estimateur d'état est étudiée dans ce but. Les simulations sont vérifiées expérimentalement en utilisant une méthode permettant de mesurer des vibrations de l'ordre de 10-9m
Gilbert, Pierre. "Valorisation des actifs financiers avec mesure de richesse agrégée." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0006/MQ44731.pdf.
Sangare, Yaya. "Etude des défauts électriquement actifs dans les couches minces (150 Å) de SiO2 par photoémission interne." Montpellier 2, 1991. http://www.theses.fr/1991MON20001.
Caniard, Thomas. "Couplage optomécanique, action en retour et limites quantiques dans les mesures optiques ultrasensibles." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2007. http://tel.archives-ouvertes.fr/tel-00164656.
Notre montage permet de mener une étude approfondie des sources de bruit dans une mesure optique et des limites de sensibilité associées. Nous nous intéressons en particulier au couplage optomécanique résultant de l'action réciproque entre la lumière et un miroir mobile. Par l'intermédiaire de la force de pression de radiation, les fluctuations quantiques d'intensité du faisceau génèrent un bruit de position supplémentaire du miroir. Ce bruit constitue l'action en retour de la mesure de position et entraîne l'existence de limites quantiques de sensibilité.
Parmi les améliorations réalisées sur le montage, nous avons mis en place un système de double injection de faisceaux laser dans la cavité afin d'étudier les effets quantiques du couplage optomécanique. Nous avons mis en évidence une suppression de l'action en retour de la mesure par interférence destructive entre les réponses des deux miroirs formant la cavité. Nous discutons des applications potentielles de cet effet afin d'améliorer la sensibilité des mesures optiques, notamment pour les détecteurs doublement résonnants d'ondes gravitationnelles.
Godoy-Hidalgo, Maria Cosette. "Mesurer l’action publique : les dimensions politiques de la mise en place des instruments de mesure de la performance publique au Chili (1990-2010)." Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAH025.
Like other capitalist democracies, Chile has implemented performance measurement instruments to improve the efficiency and effectiveness of public action. Under the influence of the New Public Management paradigm, the governments of the Centre-Left Coalition (1990-2010) have put in place tools from the private sector to ensure standards of objectivity, impartiality and performance in the public sector. Through the approach of government sciences and public action instrumentation and following the hypothesis put forward by Pierre Lascoumes and Patrick Le Galès questioning the neutrality of these tools, this PhD thesis work questions the political dimensions of the implementation of public management and performance measurement tools in Chile. As such, we will analyze the importance of the political context in the implementation and translation of these instruments to the Chilean reality, the challenges of their implementation, and their effects on the power and accountability relationships between the different actors who participated in their implementation. To achieve this, the research uses data from semi-directive interviews with stakeholders as secondary sources such as government speeches and official documents
Foucault, Valérie. "Evaluation de l'aptitude physique d'une population active : le MST (mesure du seuil de tolérance à l'effort)." Caen, 1991. http://www.theses.fr/1991CAEN3056.
Louf, Valentin. "Étude de l’eau atmosphérique par instrumentation micro-onde active et passive." Electronic Thesis or Diss., Lille 1, 2014. http://www.theses.fr/2014LIL10205.
The detection of dangerous convective precipitating system is crucial for the civil aviation safety. In this work, we develop applications for the aviation safety by using active (radar) and passive (radiometer) microwave instrumentation in order to detect precipitating systems, notably hail area. We also develop applications for the meteorology, i.e. a climatology of water vapor and the anomalous propagation of the microwave signal that is inducted by water vapor.In the first part, we study the best configuration for civil aviation airborne radars for the observation of precipitating systems, notably the frequency and the beamwidth. We have applied the constrain on the radar antenna of civil aviation that its size and its weight. Then we study the results of the dual-wavelength technic for the detection of hailstorm. This part aims to improve the quality of the observations made by civil aviation airborne radars. In the second part, we study the climatology of the water vapor diurnal cycle, and its seasonnal variations, in West Africa. Water vapor is one of the most important atmospheric gases (greenhouse effect, radiation, hydrological cycle, etc.), it is thus necessary to know in details the water vapor distribution in the troposphere. Based on this water vapor study, we then analyse the impact of the water vapor on the air refractivity and the propagation of microwaves. A climatology of anomalous propagation has been built for the instrumentation that uses microwaves
Corral, Gonzalez Joël Eduardo. "Mesure de paramètres de qualité de service dans les réseaux IP." Rennes 1, 2004. http://www.theses.fr/2004REN10121.
Gaudin, Gilles. "Etude du régime thermiquement activé de l'effet tunnel d'aimantation par mesures de chaleur spécifique dépendante de la fréquence." Université Joseph Fourier (Grenoble), 2001. http://www.theses.fr/2001GRE10197.
Cailliez, Jonathan. "Contributions à la modélisation et la commande de capteurs de forces actifs pour la méso et micro-robotique." Electronic Thesis or Diss., Sorbonne université, 2020. http://www.theses.fr/2020SORUS278.
This thesis focuses on the development of an original instrumentation, with performances beyond the state of the art, for the characterization and the measurement of forces at the small scales. The work covers the measurement of a wide range of forces involved in meso and micro-robotics, from intermolecular forces of the order of a few µN to forces at the Newton level. The focus lies in the development and implementation of sensors based on an active technology particularly adapted for the characterization of forces with a variable gradient thanks to a quasi-infinite sensor stiffness in closed loop. Three main contributions have been made. On the methodological aspect, a new robust hybrid control approach based on Eigen structure assignment has been proposed and experimentally validated for the robust characterization of intermolecular interaction forces using an Atomic Force Microscope (AFM). This characterization has allowed defining the basis of the specifications for the design and the control of active sensors better suited to finely characterize unstable areas in which the force gradients are important. The second contribution lies in the development, design, control and implementation of an original MEMS (Micro-Electro-Mechanical System) type active sensor with the particularity of having a linear electromechanical characteristic over its entire measurement range, i.e. +- 20 µN, with a bandwidth greater than 2kHz. The third contribution lies in the proposition of a new architecture for the active measurement of forces over ranges from mN to N based on a magnetic actuation and an air bearing. This sensor has been implemented for the measurement of magnetic forces with unstable areas when the distance between the sensor tip and the magnetic sample is below a certain threshold. The perspectives to this thesis are numerous in materials science, biology and more generally in physics. It particularly opens a new path in scientific research related to active AFM
Laurent, Justine. "Mesures de la force de Casimir à basse température." Phd thesis, Université de Grenoble, 2010. http://tel.archives-ouvertes.fr/tel-00576595.
Laurent, Justine. "Mesures de la force de Casimir à basse température." Phd thesis, Grenoble, 2010. http://www.theses.fr/2010GRENY070.
The Casimir force, named after the Dutch physicist who predicted in 1948 the existence of this attractive force in an ideal conguration of two perfectly conducting and parallel plates, is due to quantum-mechanical effects. It results from electromagnetic fluctuations of vacuum and cannot be neglected anymore in the performance of the nano-mechanical systems (NEMS), which are currently developed and could also revolutionize the microelectronics industry. However, the study of the corrections brought by the surface conductivity or by the dielectric stacks has just started. This thesis work presents the achievement of a new instrument dedicated to the measurement of the Casimir force between two surfaces at the micron scale. We have adapted the technique performed during the G. Jourdan's PhD thesis to a cryogenic environment in order to reach the sensitivity needed to investigate complex surfaces. The viscous damping of the force probe (AFM cantilever) due to the environmental fluid confined between the sphere glued at the tip of the AFM cantilever and a sample has been analysed. Measurements at 4K have revealed an opto-mechanical effect induced by laser noise. Finally, our first tests between two low rough gold surfaces have showed the presence of a parasite force. We have found out the origin of this force and succeeded to remove it. The first measurement of the Casimir force between a gold sphere and a silicon sample has been performed
El, Maarabani Mazen. "Verification and test of interoperability security policies." Phd thesis, Institut National des Télécommunications, 2012. http://tel.archives-ouvertes.fr/tel-00717602.
Herbulot, Ariane. "Mesures statistiques non-paramétriques pour la segmentation d'images et de vidéos et minimisation par contours actifs." Phd thesis, Université de Nice Sophia-Antipolis, 2007. http://tel.archives-ouvertes.fr/tel-00507087.
Saurel, N. "Conception et réalisation de systèmes de contrôle non destructif par mesure du rayonnement nucléaire et métrologie associée pour la quantification des radionucléides contaminant les déchets et les procédés de l'industrie nucléaire." Habilitation à diriger des recherches, Université Blaise Pascal - Clermont-Ferrand II, 2013. http://tel.archives-ouvertes.fr/tel-00826891.
Pes, Salvatore. "Nanostructures-based 1.55 μm-emitting Vertical-(External)-Cavity Surface-Emitting Lasers for microwave photonics and coherent communications". Thesis, Rennes, INSA, 2019. https://tel.archives-ouvertes.fr/tel-02892844.
The work presented in this dissertation focus on the development of InP-based semiconductor vertical-cavity lasers, based on quantum nanostructures and emitting at the telecom wavelengths (1550-1600 nm). A new technological process for the realization of compact VCSELs is described. This process (named TSHEC) has been employed to realize optically-pumped VCSELs, integrated onto a host Silicon platform, with good performances. The same process has been adapted to develop an electrically-driven version of VCSELs: a preliminary study of the confinement section based on a InGaAs-BTJ is presented, together with the development of a mask set. Thanks to the development of the liquid crystals μ-cell technology (in collaboration with LAAS, IMT Atlantique et C2N), we realized a tunable photodiode at 1.55 μm, and a tunable VCSEL is currently under development. This work also presents the first realization of a 1.6 μm- emitting optically-pumped quantum dashes-based VECSELs, and its characterization in multi-mode and single-frequency regime. Finally, the realization of an experimental setup for the investigation of the coupling between two orthogonal eigenstates of a bi- frequency 1.54 μm-emitting SQW-VECSEL has been conceived and realized. This setup, which allowed the direct quantification of the coupling constant on such a device, in the near future will allow performing the same study on anisotropic structures like quantum dashes or quantum dots, with the objective of studying the inhomogeneous broadening effect observed in these gain regions
Saint-Sardos, Adrien. "Microfluidique pour la mesure de bio-molecules secretees." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLX094.
This thesis presents some results about sécrétome quantification by 3D-organized mammalian cells. Secretome has a key role in cell-to-cell interactions, and ultimately contributes to collective cellular response. The characterization of individual diversity within a population for protein secretion is therefore required to better understanding the link between cellular phenotype and secretory functions. Researches of the last two decades have led to multiplexed and high-throughput methods for quantifying cellular secretion of anchorage-independent cells. But these methods are difficult to transpose to cells needing a physical substrate to adhere on. In this manuscript is presented a microfluidic platform that allows the culture of anchorage-dependent cells as a dense array of spheroids. In this platform, we developed an immuno-assay to quantify the presence of the cytokines IL-1β, based on antibody-grafted beads. Using fluorescence microscopy and image analysis, an optical signal read on micrometric beads is translated to a biological information on cytokine concentration. As diffusion times compete with reaction kinetics within our device, a theoretical study of cytokine transport and capture inside the droplet is developed.This immune-assay is tested on human mesenchymal stem cells spheroids. hMSCs constitute a cell population of progenitors of several cellular types of connective tissues and display important trophic functions while cultivated in 3D. In our microfluidic device, we demonstrated important secretions of IL-1β, but also of the angiogenesis chemokine VEGF. A numerical model of reaction-diffusion allows to predict characteristic times of cytokine capture by the immune-assay. In addition of evidencing VEGF accumulation over time, the assay unravels the effect of a non-steroidal drug on VEGF secretion.Signals associated with intra and extracellular production of VEGF by spheroids show a wide variability within a single biological replicate. The last chapter is therefore trying this variability with heterogeneities at the cell level, as there seems to be a collective effect within spheroids that goes beyond the simple summation of cellular features
Perot, Bertrand. "Optimisation des méthodes de mesure neutronique active pour les déchets radioactifs et contribution à la modélisation d'un dispositif industriel." Université Joseph Fourier (Grenoble), 1996. http://www.theses.fr/1996GRE10092.
Joulin, Yves. "Métabolisme, méthodes de dosages et intérêt de la mesure de la 3-méthylhistidine dans les liquides biologiques." Paris 5, 1988. http://www.theses.fr/1988PA05P192.
Ceccaldi, Marie. "Combinaison de mesures actives et passives pour l'étude des nuages dans le cadre de la préparation à la mission EarthCARE." Versailles-St Quentin en Yvelines, 2014. https://hal.archives-ouvertes.fr/tel-01119939.
Clouds play a major role in Earth radiation budget and balance. The characterization of clouds in weather and climate models needs better understanding of cloud processes and more information on cloud microphysical properties. Such information can be obtained from active sensors like radar and lidar onboard CloudSat and CALIPSO satellites which are part of the A-Train constellation. The purpose of this thesis is first to improve and study the DARDAR method which provides cloud microphysical properties from variational scheme. Secondly this thesis deals with the adaptation of the method to the EarthCARE mission, which will, in 2016, board a lidar with high spectral resolution capabilities and a Doppler radar. The method for hydrometeors classification, DARDAR-MASK, was improved and adapted to the EarthCARE instruments by means of airborne RALI campaigns. Cloud properties retrieval method, DARDAR-CLOUD, was modified too. Variability of DARDAR-CLOUD retrieval to different microphysical models used was studied as well and radiometric measurements assimilation in the variational scheme
Bugnazet, Thomas. "Métrologie dans les réseaux IP : performance du DNS et ENUM." Paris 6, 2006. http://www.theses.fr/2006PA066451.
The new IETF protocol called ENUM enables the linkage in a DNS tree between a phone number in the E164 scheme and a set of data, hence facilitating the RTC-VOIP convergence but requiring unusual performance from the DNS In order to study the performance of ENUM, a DNS simulator, in which all the limiting factors are mastered, was developed. This simulator is validated by comparing its outputs with real measurements in a test bed. In this simulator the loss rate and delays on IP links are modelled by hidden Markov models. These new models and their parameters result from active measurements (traces are treated with a post-synchronization algorithm). The local DNS server response time as well as its loss rate were also measured and modelled thanks to a new measurement methodology and its tools. Besides, for the traditional DNS, the DNS traffic around the INT cache server was sniffed (passive measurement), anonymized and then analysed
Jacobi, David. "Mesures de l'activité physique en conditions de vie courante : validité et applications chez des sujets peu actifs." Thesis, Tours, 2011. http://www.theses.fr/2011TOUR3306/document.
Physical inactivity is a risk factor for chronic diseases and is recognized as a major public health issue. Validated methods are essential to describe accurately physical activity (PA). The 1st aim of this work was to assess the validity of PA assessment techniques. The 2nd was to compare the results of recall questionnaires evaluating PA context with objective PA measures. The 3rd was to assess the usefulness of objective methods in the assessment of some determinants of PA. We measured free-living PA with different methods (indirect calorimetry, actimetry, recall questionnaire assessing PA context) in individuals with low PA levels (obese subjects, type 2 diabetic patients, inactive subjects). The results highlight the usefulness but also the limits of the methods of PA measurement in daily life conditions. The choice of an assessment method will influence the study results and must be adapted to the unique ways in which the least active individuals engage in PA. Selecting the appropriate method is a pre-requisite for improving our knowledge on the relations between PA and health in order to guide PA promotion in the least active segments of the population
Hassine, Souha. "Application du pont actif différentiel à la mesure de la température faible consommation sur CMOS." Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20217/document.
Several sensors using standard microelectronic technologies (MOS) have been developed based on mechanical or thermal structures to perform transduction functions by the ‘Microsystems' Team of the LIRMM. These sensors are mainly resistive thanks to their design simplicity and low cost. However, one of their major problems, power consumption and noise are the most notable. In another thesis, a new conditioning circuit called 'Active Bridge' has been proposed. This circuit, presented as an 'alternative' to the traditional Wheatstone bridge, reduces considerably the power consumption while providing an important signal amplification. In this context, the objective of this thesis is to evaluate the usefulness of the Active Bridge in a temperature sensor application.The temperature measurement is at the heart of many applications. Many instruments have been developed, the best known remaining mercury thermometer. Today, the temperature sensors are widely used in measuring systems, instrumentation and control systems. Given the wide application areas, propose, in the context of embedded systems, a resistive temperature sensor ultra-low power, high performance and small remains relevant.After an overview of the existing solutions for this kind of application, the first part of the thesis introduces the principle of the differential Active Bridge. So, different architectures of temperature sensors optimized in terms of consumption are proposed, modeled and characterized. These studies show the dependency of the operating point of the sensor to the process and mismatch variations process. Therefore, in order to control the operating point, a voltage to current conversion has been implemented. Finally, the sensor has been integrated into a Sigma Delta modulator to implement a digital feedback. Finally, a conclusion of the issues and different results have been discussed as conclusion in this manuscript