Teses / dissertações sobre o tema "Dispositifs à bas coût"
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Rabobason, Yvon Georges. "Modélisation de système antennaire flexible à bas coût pour objets communicants non planaire". Rouen, 2016. http://www.theses.fr/2016ROUES060.
Texto completo da fonteFlexible electronics is currently considered as one of the technological solutions to face up to geometric constraints, lower cost and technological requirements. This emergence will ultimately drive the market for connected clothing, implanted electronics (in-body electronics). However, the flexible technology is not mature and has some issues that remain to lift as the choice of substrates both effective, environmentally friendly and at lower costs, modeling (analytic or digital) of a system or flexible subsystem, or the analysis of electromagnetic phenomena related to non-planar geometry. This manuscript presents the memory of my PhD thesis that focuses on the modeling of flexible antenna system for low-cost non-planar communicating objects. First, the different parameters such as the quality factor, antenna efficiencies, gain or bias, for evaluating the performance of an antenna are introduced. Subsequently, research work on flexible substrate based different antenna structures is presented. The main characteristics of flexible plastic substrates commonly used are addressed. The choice towards the substrates Kapton HN, as the best compromise cost-effectiveness robustness is justified. The influence of the antenna curvature constitutes the main object of the present PhD thesis. In this way, the study on the EM phenomena associated with the use of a flexible patch antenna structure is developed. Novel analytical formulas for assessing the antenna radiation efficiency in discrete curvatures scenarios are established. In addition, a methodology providing an analysis and modeling approach to passive and active 1×2 antenna arrays is presented and validated. Finally, two new structures of flexible high performance antennas in terms of bandwidth and radiation efficiencies are designed and implemented. The Kapton-based broadband structures are based on slots antenna topology with new matching adaptation technique by the use of lumped elements. The influence of the curvature on the slot antenna prototypes are analyzed and discussed
Nassar, Maxime. "Contre-mesures à bas coût contre les attaques physiques sur algorithmes cryptographiques implémentés sur FPGA Altera". Electronic Thesis or Diss., Paris, ENST, 2012. http://www.theses.fr/2012ENST0010.
Texto completo da fonteSide-Channel Analysis (SCA) and Fault Attacks (FA) are techniques to recover sensitive information in cryptographic systems by exploiting unintentional physical leakage, such as the power consumption. This thesis has two main goals: to draw a review of the state of the art of FPGA-compatible countermeasures against SCA and implement t the selected ones with the minimum area and performances overhead. Symmetrical algorithms, specially AES, are studied and several vulnerabilities of usual protections, namely Dual-rail with Precharge Logic (DPL) and masking are analysed, as well as the issue of performance and area overheads. In this context, three new countermeasures are considered: 1. Balance placement and routing (PAR) strategies aiming at enhancing existing DPLs robustness when implemented in modern FPGAs. 2. A new type of DPL called Balanced Cell-based Dual-railLogic (BCDL), to thwart most of the known DPL weaknesses. BCDL also possess a fault resilience mechanism and provides implementation optimisations on FPGA, achieving competitive performances and area overhead. 3. The Rotating S-Box Masking (RSM), a new masking technique for the AES that shows high leveles of robustness and performances while bringing a significant reduction of the area overhead. Finally, several new SCAs are presented and evaluated. Firstly the “Rank Corrector” a SCA enhancement algorithm. Secondly, The FPCA, introduces a novel SCA distinguisher based on the PCA. Then, combinations of either acquisition methods or SCA distinguishers are discussed and show significant decrease in the number of measurements required to perform a successful attack
Nassar, Maxime. "Contre-mesures à bas coût contre les attaques physiques sur algorithmes cryptographiques implémentés sur FPGA Altera". Phd thesis, Télécom ParisTech, 2012. http://pastel.archives-ouvertes.fr/pastel-00790669.
Texto completo da fonteHabis, Christelle. "Development of ZnO-FTO nanocomposites for the use in transparent conductive thin films". Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0192.
Texto completo da fonteMy thesis work entitled “Development of ZnO-FTO nanocomposites for the use in transparent conductive thin films” is supervised by Professor Michel Aillerie at University of Lorraine. This work was mainly made at the “Laboratoire des Matériaux Optiques, Photoniques et Systèmes” LMOPS in Centrale Supélec, Metz. Although this work forms a whole in the elaboration of transparent conductive oxides, it is divided into two parts. The first part consists on identifying the properties of bulk materials (ZnO and FTO) deposited in the form of thin film. Whereas, the second part is about the elaboration and characterization of Zinc Oxide (ZnO) and Aluminum doped Zinc Oxide (AZO) nanofibers, then associated to FTO thin films to form nanocomposite. The main objective of this work is to make flexible electrodes using low cost and abundant material, but also improving the optical properties and more specifically the haze factor of the nanocomposite layers.Transparent conductive oxides (TCOs) are technologically significant class of materials extensively used in thin film solar cells due to their ability to transmit light and collect charge carriers. In addition to the fundamental qualities of transparency and conductivity, the TCOs are frequently desired to have a certain degree of surface roughness (i.e., texture) in order to effectively scatter transmitted light into the active materials, therefore lengthen the optical path and, as a result, enhance the performance of the cell and light absorption. This thesis focuses on the development of low-cost fabrication techniques for transparent oxide layers using non-polluting materials to enable the functionalization of operational devices with high efficiency for renewable energy production. The choice was made to study tin-based TCO layers doped with fluorine, F:SnO2, known as FTOs for "Fluor Tin Oxides". FTOs are wide band gap oxides, like ZnO, TiO2, Al2O3, pure or doped. In principle, these layers have a high scattering factor, as defined above, in order to improve the optical path and absorption. In addition, the optical texture of TCOs can be easily controlled by depositing suspensions of nanostructures before the film deposition. Generally, these nanostructures are nanoparticles or even carbon nanowires or metallic nanowires (silver, copper, ...) and more recently nanowires of TiO2 (presenting the disadvantage of the titanium element) or of undoped ZnO which unfortunately decrease the conductivity due to the increase of the interface resistance with the concentration of the nanoparticles.Therefore, we propose the study of FTO thin films, pure and also in the presence of ZnO and AZO nanofibers by electrospinning from a PVA-based solution in order to have a nanostructured layer with improved transparency and electrical conductivity properties to be integrated as transparent electrodes in photovoltaic cells, meeting the performance criteria defined above. With the characterization techniques available in the LMOPS laboratory and the University of Lorraine (SEM, Raman, EDX, DRX, UV-vis Spectro, ATG, AFM, profilometer) the growth will be followed by morphological and structural studies of the layers. Finally, electrical and optical properties, in particular absorption and scattering factor, will also be extensively investigated on selected layers with the best structural and morphological properties and the minimum of interface defects when deposited on a PV structure
Duval, Sébastien. "Constructions pour la cryptographie à bas coût". Electronic Thesis or Diss., Sorbonne université, 2018. http://www.theses.fr/2018SORUS078.
Texto completo da fonteThis thesis explores the construction of symmetric cryptography primitives. We reach better constructions than that of the literature, we a focus on the reduction of implementation costs. We study three types of primitives: block ciphers, which are the most commonly used in symmetric cryptography, a stream cipher designed for a specific application and a message authentication algorithm. We reduce the costs of the two main components of block ciphers: S-boxes and diffusion matrices. Feistel and MISTY-like structures appear to be a good choice to design secure S-boxes at a low cost, and lead us to new S-boxes with the best known trade-off between security and implementation cost. We also study the Butterfly structure which yields S-boxes with an excellent security. As for diffusion matrices, we develop an algorithm to look for formal matrices in a polynomial ring, then we instantiate its outputs to obtain matrices which are optimal in terms of diffusion at a lower cost than those of the literature. We also identify a weakness in the stream cipher FLIP, designed to fit some very specific cost constraints. We show that FLIP requires a different analysis than other stream ciphers and deduce from it an attack, which led to an update in FLIP to get a more resilient cipher. Finally, we study MAC algorithms, which are used to authenticate messages. Combining works from the literature, we build a MAC which is less costly than those used in practice with an equivalent security, aiming at an implementation on 32-bit micro-controllers
Bouhamri, Zine-Abidine. "Transmission multi-standards sur lien optique bas-coût". Phd thesis, Université de Grenoble, 2013. http://tel.archives-ouvertes.fr/tel-00957588.
Texto completo da fonteCoisel, Iwen. "Authentification et Anonymat à Bas-coût : Modélisations et Protocoles". Caen, 2009. http://www.theses.fr/2009CAEN2041.
Texto completo da fonteIn our daily life, security of many applications are based on cryptographic mechanisms. In some of them, privacy issues are a major concern. For example in internet context, a user expects the service provider not to divulgate his identity. In this thesis, I first give a formal definition of zero-knowledge proofs of knowledge (ZKPK), very useful for designing digital signatures. I prove the security of a generic construction of proofs of knowledge of discrete logarithm relations set. Then, I present state of the art of different signature schemes ensuring users' anonymity. Afterwards I adapt these protocols to the cooperative set-up, in which an intermediary helps the user perform some computations during the protocol. I also define a formal security model which is robust against corruption of the intermediary, while improving protocol efficiency. In the second part of this thesis, I present the security requirements for RFID tags authentication protocols. As these small embedded devices are potentially integrated into many various products, they must be intraceable so that nobody can trace their holder. As anonymity does not provide this property on its own, it must be included in the security model. Finally, I describe two authentication protocols which provide this security level. The first one uses a secret key infrastructure and a key update mechanism. The other one uses a public key infrastructure and an encryption algorithm
Coggia, Daniel. "Techniques de cryptanalyse dédiées au chiffrement à bas coût". Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS217.
Texto completo da fonteThis thesis contributes to the cryptanalysis effort needed to trust symmetric-key primitives like block-ciphers or pseudorandom generators. In particular, it studies a family of distinguishers based on subspace trails against SPN ciphers. This thesis also provides methods for modeling frequent cryptanalysis problems into MILP (Mixed-Integer Linear Programming) problems to allow cryptographers to benefit from the existence of very efficient MILP solvers. Finally, it presents techniques to analyze algebraic properties of symmetric-key primitives which could be useful to mount cube attacks
Lefranc, David. "Authentification asymétrique à bas coût et vérification assistée par ordinateur". Caen, 2005. http://www.theses.fr/2005CAEN2024.
Texto completo da fontePassault, Grégoire. "Optimisation de la locomotion de robots bas coût à pattes". Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0297/document.
Texto completo da fonteA promise of legged robots is being able walking on irregular or uneven floor. It is already used nowadays in education and entertainment applications. We introduce the Metabot platform, an open-source quadruped robot developped for education. This takes place in current technological context which allows, thanks to an access to fast prototyping and off-shelf components, building legged robots that were formerly only present in laboratories. This platform was used for teaching in secondary schools, allowing students to discover robotics, and especially programming. We then describe an environment designed to study legged robots locomotion, extending the expert controller designed for Metabot. We realized some physics simulation experiments and analyzed it to get a better understanding of the legged locomotion underlying rules. At last, we get a closer look at biped locomotion, for which stability problems arise. When developping our Sigmaban platform, a small-sized humanoid robot created to participate in RoboCup soccer, we designed foot pressure sensors that allow us to estimate the robot center of pressure. We exploit these sensors to improve the lateral stability on the robot, creating a closed-loop walk
Dogheche, El Hadj. "Transmission optique d'un signal analogique hyperfréquence et digital bas débit". Lille 1, 1993. http://www.theses.fr/1993LIL10056.
Texto completo da fonteMerzouk, Khalil. "ÉTUDE D'UN SYSTÈME BAS COÛT DE TRANSMISSION OPTIQUE PAR MULTIPLEXAGE TEMPOREL". Phd thesis, Grenoble INPG, 2008. http://tel.archives-ouvertes.fr/tel-00348066.
Texto completo da fonteMekki, Sami. "Architecture et traitement numérique pour les communications UWB à bas coût". Paris, ENST, 2009. http://www.theses.fr/2009ENST0069.
Texto completo da fonteThis thesis report deals with a low cost IR-UWB receiver for high-data rates (100Mbps). The system under consideration uses a PPM modulation with a simple analog energy detector. In ordeer to overcome the problems inherent to high-data rates, such as inter-symbol interference and intra-symbol interference, a probabilistic equalizer is proposed. On this study, we define a well matched energy model that takes advantage from the interference levels. COmputer simulations are performed on the channel models of IEEE 802. 15. 3a Task Group. Numerical results show that the energy equalizer improve the receiver performances if perfect CSI was assumed. Channel parameters necessary for equalization are estimated by the mean of the EM algorithm. The energy equalizer and the EM algorithm are jointly run into the loop of an iterative channel decoder in order to enhance the BER performance and achieve 100Mbps data rate. We show that the EM algorithm is capable of estimating the channel parameters as accurately as the perfect CSI. Besides, a new training sequence for channel estimation is proposed. This allows to obtain a very low complexity channel estimation with regards to the EM algorithm. Finally, the hardware implementation feasability of the probabilistic equalizer is studied. For this purpose, we apporximate and replace certain complex mathematical functions, such as the chi-squared likelihood function, by ones less complex. Then, the computational complexity is further reduced by performing the calculations in the logarithmic domain. Fixed-point data types simulations are carried out and compared to the results obtained from the reference floating point non-approximated functions
Sion, Charles. "Réalisation d’une caméra infrarouge à bas coût pour application grand public". Thesis, Lille 1, 2011. http://www.theses.fr/2011LIL10094/document.
Texto completo da fonteThe thermal radiation emitted by human body can be detected in the 8-14 µm range by an infra-red sensor. Cameras imagined from this type of detectors were initially reserved for army personal usage but the market is in a large growth due to commercial applications like thermography or human detection. Thermal detectors microbolometers are the most spread technologies with 95% of the market but some others are showing interesting results as thermoelectrical arrays. This document explains the realisation of an infrared camera that can be used for human detection using a technology developed in the group. Contrary to the bolometric matrices based on a variation of electrical resistance, this sensor working by thermoelectric effect does not require power supply and the associated electronic interface is very simple. A special attention was related to the reduction in the manufacturing costs by decreasing the size of the thermoelectric pixels and using a polyethylene Fresnel lens in order to use this type of system in the individual housing. Series of 5x5, 7x7, 10x10 pixels microsensors were modelled and realized during this thesis as well as a complete imaging device using of 7x7 pixels array. The mathematical model developed during this work shows that a further increase in length reduction is possible if more pixels are needed
Theillet, Gérald. "Développement d'un support microfluidique papier pour le diagnostic bas coût d'arboviroses émergentes". Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0725/document.
Texto completo da fonteThe incidence of arboviruses infections has increased dramatically in recent decades in tropical and sub-tropical areas worldwide. Dengue and chikungunya viruses are typically transmitted by mosquitoes and can cause a wide range of symptoms, and sometimes death. Although conventional diagnostic tests can provide diagnosis of acute infections, access to these tests is often limited in developing countries. Early and prompt diagnosis is crucial to improve patient management. Consequently, there is an urgent need to develop affordable, simple, rapid, and robust tools that can be used at ‘Point of Care’ settings.We developed and evaluated a PAD for the detection of the dengue Non Structural 1 (NS1) viral protein in blood and plasma samples. The PAD was able to detect specifically 10 ng.mL-1 of NS1 protein in various sample types and in 6-8 minutes. Secondly, an improved version of the PAD obtained by laser cutting was designed and tested for the detection of dengue NS1 protein and virus-specific IgM in blood and plasma. Each parameter could be detected in 8 minutes. PAD development performed on dengue fever was then applied to the detection of chikungunya virus IgM in human sera, using viral Pseudo-Particles (PPs). These synthetic antigens have proven to be powerful tools for specific IgM detection. The results obtained showed a sensitivity of 70.6% and a specificity of approximately 98% with a time to results of less than 10 minutes. The PAD showed few cross reactions with other arbovirusess. The PPS were finally characterized with different physico-chemical methods in order to determine the key factors of their performances
Calenzo, Patrick. "Développement de nouvelles architectures mémoires non volatiles bas coût et basse consommation". Aix-Marseille 1, 2009. http://www.theses.fr/2009AIX11051.
Texto completo da fonteThe objectives of this thesis are to conceive and to develop non volatile memories with floating gate which are low cost, low voltage consumption and compatible with a CMOS standard logic process. In order to be carried out, a state of the art has put forth the cells which are “high-achieving” in this technology. This has permitted to see the qualities and the defects of the cells and enabled to target the main points which need careful consideration. From this onwards, a calibration methodology, usable for any semi conductor device, has been developed. This methodology was put into practice on an EEPROM cell, which served as the foundations for the development of the memory cells, throughout this paper. Furthermore, a single poly silicon double implant memory cell has been studied. This cell has been developed from its operating concept to its electric validation on silicon. The manufacturing process suggested gave way to a single poly-silicon memory cell in a CMOS logic technology. In addition, the cell consumption is in perfect accordance with the low voltage consumption criteria. Finally, this cell is interesting in regards to its size which is only 1,1 μm² in a technology of 0,13 μm. This makes it the smallest existing cell for this particular type of memory. In parallel to this work, another single poly silicon cell, which exists in two different versions, has been suggested. These cells have the particularity to be created in a shallow trench isolation. This reinforces the idea of low cost because the surface of the unit cell can be reduced but at the same time remains compatible with a CMOS standard logic process. All the basics needed to create this cell have been validated electrically and give way to encouraging energy consumption results. The outlook for this work would be to improve the two developed concepts in order to have them industrialized
Yao, Thierry. "Modélisation et conception d'une mémoire non-volatile dédiée aux applications bas coût télé-alimentées". Paris, ENST, 2002. http://www.theses.fr/2002ENST0018.
Texto completo da fonteGardes, Cyrine. "Un salariat à bas coût. Le travail dans une enseigne low-cost de bricolage". Thesis, Paris, EHESS, 2019. http://www.theses.fr/2019EHES0076.
Texto completo da fonteThe current crisis of purchasing power, a very pressing problematic at the present time, contributed to the rise and success of low-price retail in various sectors of the economy (food, hardware retail, rail and train transportation), self-promoted as « low-cost » and described as a major commercial innovation, with its low margins, reduced assortment and services, and generally its low production costs. This business model, never before studied in sociology, is the object of the present work, which purpose is to illustrate the different forms taken by exploitation and capitalism, and their effect on the workforce, in a context of economical crisis. The analysis angles itself mainly on work, and was nourished by an ethnographic study in two stores and warehouses of a low-cost hardware retail chain business, that we will call « Bricostock ». We show that the activity of these « low-cost » hardware retail stores, which has similarities with other production models, is characterized by simultaneously managing a very high flow of goods with an accelerated stock rotation, and a fast customer flow, whose interactions with the salespeople therefore have to be reduced. The workers' multi-tasking activities allow an important reduction in workforce numbers, compared to the other businesses of the sector. We also show that this type of organization is based on the work of individuals with specific social characteristics : management and subaltern workers alike are more socially vulnerable than in other firms and have to accept work conditions. Lastly, from the perspective of doing a sociology of the work group's structuration, we study different configurations of the group's social relations. Peer groups, despite the work and employment conditions that could keep them from existing, are present, and they are structured by various principles of division and cohesion. We will show in which situations work peer groups seem relevant to the actors or might be made redundant by other situations : for exemple, if men are dominant in the organisation and in the work group (men make up 83 % of the sales workforce in the firm we studied, one of the highest rate in the sector of hardware retail), there are gender-mixed sociabilities based on the workers' seniority, on age, on a shared position or on common adversaries, such as management and customers. This study deals with the dynamics of reproduction or transformation of social relations in low-cost retail and with the diffuse forms of conflictuality in this type of organisation
Carcanague, Sébastien. "Algorithme de positionnement précis en environnement contraint basé sur un récepteur bas-coût GPS/GLONASS". Phd thesis, Institut National Polytechnique de Toulouse - INPT, 2013. http://tel.archives-ouvertes.fr/tel-00951914.
Texto completo da fontePorcher, Willy. "Conception, mise en oeuvre et optimisation d'électrodes composites à bas coût pour accumulateurs Li-ion". Nantes, 2008. http://www.theses.fr/2008NANT2080.
Texto completo da fonteThis work is focused on the development of LiFePO4-based positive composite electrodes of 3mAh. Cm-2 through the aqueous processing route. The viability of the aqueous route for LiFePO4 was initially evaluated with a study on its stability in water. The results show, in particular, that a protective layer of Li3PO4 of some nanometers is formed at the grains surface but without any degradation of the electrochemical performances. However, to limit the capacity loss associated with the aqueous processing, this study shows that the immersion time should be limited, the solid loading of the LiFePO4 aqueous suspension should be high, and that the natural pH should not be modified. The formulations that were developed contain a combination of water soluble polymers which satisfies three functions: the one of dispersing and stabilizing agent of the LiFePO4 and carbon black powders, the one of giving proper rheological properties to the electrode ink with respect to the tape casting process, and the one of binder to confer a satisfactory adhesion and cohesion to the electrode. Additives with various molecular structure and therefore specific properties are tested, independently, according to the function sought by their introduction. A fourth original additive was also introduced, an amino-functional synthetic polyelectrolyte, with the aim to tailor a self-assembly between the LiFePO4 active material and the carbon black electronic conductor. The electrodes of 3mAh. Cm-2 obtained are perfectly easy to handle, and their electrochemical performances are superior than those classically obtained with the N-methyl-2-pyrrolidone route, with a higher active material concentration
Nguyen, Viet Huong. "Développement d'électrodes transparentes par méthodes de dépôt à pression atmosphérique et bas coût pour applications photovoltaïques". Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAI072/document.
Texto completo da fonteThe thesis work involves the study of Indium-free Transparent Conductive Materials (TCMs), key components of many optoelectronic devices, using Atmospheric Pressure Spatial Atomic Layer Deposition (AP-SALD). This new approach shares the main advantages of conventional ALD but allows open-air, very fast deposition of high-quality nanometer-thick materials over large surfaces. We focused on the optimization of the electrical properties of Aluminum doped Zinc Oxide (ZnO:Al) films, one of the most studied Transparent Conductive Oxides (TCOs). The effect of several experimental parameters on the physical properties of the deposited films has been evaluated. The carrier transport mechanism at grain boundaries was identified to be tunneling rather than thermionic emission in highly doped ZnO, thanks to a new model we have developed using the Airy Function Transfer Matrix Method. Accordingly, the electron trap density at grain boundaries for ZnO:Al samples (2.2×1020 cm-3) prepared by AP-SALD was estimated to be about 7.6×1013 cm-2. Our model shows that grain boundary scattering is the dominant scattering mechanism in our films. We found that UV assisted annealing (~ 200 °C) under vacuum was an efficient method to reduce grain boundary traps, resulting in an improvement of mobility from 1 cm2V-1s-1 to 24 cm2V-1s-1 for ZnO and to 6 cm2V-1s-1 for ZnO:Al. We have also used AP-SALD to fabricate high-performance, stable and flexible TCMs based on metallic nanowire network. For that, we developed composite electrodes by coating silver/copper nanowires (AgNWs/CuNWs) with ZnO, Al2O3, or ZnO:Al. A thin conformal coating deposited by AP-SALD technique enhanced drastically the thermal/electrical stability of the AgNWs/CuNWs network. High optoelectronic properties (resistivity ~ 10-4 Ωcm, transmittance ~ 90 %) of the AgNW/ZnO:Al composite make them very appropriate for application as TCM, especially for flexible devices.Finally, as a soft deposition technique, AP-SALD is completely compatible to the Silicon heterojunction (Si-HET) solar cell technology in terms of interface passivation. The integration of ZnO:Al and AgNWs based TCMs to Si-HET cell has also been explored
Liu, Chao. "Dimensionnements et comparaisons de convertisseurs électromécaniques à bas coût et à grande disponibilité pour véhicules électriques". Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLC049/document.
Texto completo da fonteToday, the concerns of the energy crisis and the reduction of gas emissions stimulate the research in several electric vehicle domains. As the cost of rare earth magnetic materials has increased significantly in recent years, electrical motors without permanent magnets draw more attention, such as induction motors, wound-synchronous motors, switched reluctance motors, and synchronous reluctant motors. In this thesis, induction and synchronous reluctant machines are chosen to be studied for the electric vehicle traction application since they are low costly and fed up with similar power electronics and control strategies.Nonlinear analytical models of induction and synchronous reluctant machines are established and validated. Besides, economical and mechanical models are developed as well. Based on established analytical models, the geometry and the control parameters of these studied machines are calculated to define the total energy losses during the driving cycle. A bi-objective optimization is carried out to minimize total energy losses and motor costs. At last, the optimized machines are compared from their electric, energetic and economic performances, with the help of the Pareto Fronts obtained
Jacquemoud-Collet, Fanny. "Etiquette RFID bas coût sur support papier : optimisation du procédé industriel innovant / intégration d’une fonctionnalité capteur". Electronic Thesis or Diss., Montpellier 2, 2014. http://www.theses.fr/2014MON20194.
Texto completo da fonteThe RFID, for Radio Frequency Identification, has grown considerably in recent years become an essential mode of traceability and identification. Market players are numerous and among them, Tageos (Montpellier, France) established since 2008 an innovative process for manufacturing the RFID tag on paper, economic and ecologic. However, even if the performances obtained during a previous work (Thesis C. Ramade 2008-2011) were sufficient to allow mass production, they are not optimal in particular with respect to the established results in laboratory. It is in this context that ranks this work which is always carried out in close collaboration between the Institute of Electronics of South and TAGEOS company S.A.S. Our efforts were focused : on process optimization of realization of RFID antenna working on the analysis, methods or protocols and technical resources on the preparation of the paper substrate, on alternative and complementary solutions to realize RFID antenna and RFID chip bonding and on the reliability and quality of finished products. Moreover, in this work we have also demonstrated the valorization of our low cost RFID tag by integrating a sensor functionality. The industrial process of producing of this tag taking accounts of TAGEOS process
Jacquemoud-Collet, Fanny. "Etiquette RFID bas coût sur support papier : Optimisation du procédé industriel innovant / intégration d’une fonctionnalité capteur". Thesis, Montpellier 2, 2014. http://www.theses.fr/2014MON20194.
Texto completo da fonteThe RFID, for Radio Frequency Identification, has grown considerably in recent years become an essential mode of traceability and identification. Market players are numerous and among them, Tageos (Montpellier, France) established since 2008 an innovative process for manufacturing the RFID tag on paper, economic and ecologic. However, even if the performances obtained during a previous work (Thesis C. Ramade 2008-2011) were sufficient to allow mass production, they are not optimal in particular with respect to the established results in laboratory. It is in this context that ranks this work which is always carried out in close collaboration between the Institute of Electronics of South and TAGEOS company S.A.S. Our efforts were focused : on process optimization of realization of RFID antenna working on the analysis, methods or protocols and technical resources on the preparation of the paper substrate, on alternative and complementary solutions to realize RFID antenna and RFID chip bonding and on the reliability and quality of finished products. Moreover, in this work we have also demonstrated the valorization of our low cost RFID tag by integrating a sensor functionality. The industrial process of producing of this tag taking accounts of TAGEOS process
Hoarau, Christophe. "Dispositifs accordables en radiofréquence : Exemples d'un adaptateur d'impédance accordable et d'un filtre passe-bas contrôlé optiquement". Phd thesis, Université Joseph Fourier (Grenoble), 2008. http://tel.archives-ouvertes.fr/tel-00342727.
Texto completo da fonteL'adaptateur d'impédance accordable a été réalisé en technologie hybride : structure coplanaire et composants montés en surface. La topologie choisie est une structure en Π avec comme composant accordable un varactor en série avec une inductance. Les simulations et les mesures sont en très bon accord. L'adaptateur couvre largement l'abaque de Smith, les impédances variant entre 6 Ω et 1 kΩ en module, avec un accord en fréquence sur une bande relative de 50%.
La seconde étude a porté sur un filtre passe-bas à structure périodique. Après avoir étudié une variation périodique particulière de l'impédance caractéristique (en forme d'exponentielle de sinusoïde) grâce à la théorie des modes couplés, une étude des possibilités d'utilisation du contrôle optique dans cette structure a été menée et un prototype de filtre passe bas a été réalisé avec les moyens de la salle banche de l'IMEP-LAHC. L'accord en fréquence du filtre est fait par le contrôle optique de défauts dans le plan de masse. Ceci permet une variation théorique de la fréquence de coupure de 1 GHz.
Quoizola, Sébastien. "Epitaxie en phase vapeur de silicium sur silicium mésoporeux pour report sur substrats économiques et application photovoltai͏̈que bas coût". Lyon, INSA, 2003. http://theses.insa-lyon.fr/publication/2003ISAL0078/these.pdf.
Texto completo da fonteThin film solar cells by layer transfer process is a very promising way to reduce material cost in photovoltaïc industry. The aim of this study is to transfer thin silicon layers (50 µm) on cheap substrate. In order to warranty a highly conversion efficiency, monocrystalline silicon is required. Thin monocrystalline silicon film is grown on mesoporous silicon by vapor phase epitaxy. The porous silicon layer presents a double porosity structure and acts as both a seeding layer and a sacrificial layer. During hydrogen high temperature annealing, pores are coarsened in the low porosity layer and enlarged in the high porosity layer. These structural modifications allow the growth of the epitaxial silicon layer and its separation from the silicon substrate. As obtained thin silicon film serves as the active layer in an one side solar cell with interdigited contacts. Substrate can be then re-used for a novel thin silicon film
Esteve, Aurore. "Isolement de biomarqueurs cellulaires et moléculaires en oncologie et développement d'approches bas-coût pour leur analyse en routine clinique". Thesis, Toulouse, INSA, 2018. http://www.theses.fr/2018ISAT0048.
Texto completo da fonteThe objective of this work has been to develop novel micro-devices for the isolation of circulating tumor cells as well as exploring different techniques to facilitate analysis of CTCs at the cellular and molecular level in clinical routine. A first innovative approach of in vivo CTC capture exploiting their specific physical traits was considered. Placing the capture micro-device directly within the bloodstream could allow the screening of a bigger volume of blood and thus provide a higher and more representative number of CTCs to analyze. Different techniques aiming to spread the use of liquid biopsy in clinical routine by simplifying and decreasing the cost of analysis were explored. Among these techniques, directed capillary assembly conceived to stretch and immobilize 1D biomolecules enabled the isolation of free circulating DNA fragments from whole blood samples. In the context of precision medicine, another approach may be to test the efficacy of drugs on CTCs isolated from the patient himself so as to personalize the treatment. In this perspective, we integrated the capture micro-devices into a platform allowing in situ culture of trapped cells in vitro. To recreate an environment conductive to their proliferation, the structuration of cellulosic biocompatible materials was investigated. Our results provide a set of technologies that could contribute to the democratization of liquid biopsy in clinical routine
Araujo, Viana Carlos. "Développement technologique et intégration système de VCSEL et HPT SiGe pour des applications radio-sur-fibre 60 GHz bas coût". Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1003/document.
Texto completo da fonteWireless communication technologies have become one of the most popular and indispensable part of people's lives in the recent years, offering mobility and services never before available from mobile communication until local network communication. This work is based on the frame of the French ORIGIN project and intended to explore the Home Area Network using the most recent Wi-Fi standard at 60 GHz with the goal to present a solution for the upcoming days where MultiGbit/s wireless communication will be required. The ORIGIN solution is characterized by the complementary action of two technologies: 60 GHz Wireless communication and Radio-over-Fiber (RoF) infrastructure. The project pretends to propose a real prototype based on RoF transducers and a Multipoint-to-Multipoint architecture to cover the entire house. This thesis covers from the single optoelectronic chip devices until the system implementation and the final demonstrator. The light source and the photodetector choice were very important since it dictated the RoF transducer architecture. Our choice was on 850 nm multimode devices (GaAs VCSEL and SiGe HPT) which allow relaxed constraints on the optical packaging and, therefore, low cost solutions. In terms of performances those devices are limited in a few tens of Gigahertz of bandwidth which was the reason for the intermediate frequency (IF) architecture. This thesis work addressed the electrical and optical interconnection of the optoelectronic chip devices. It explored the integration of hybrid amplification stages and passive networks within optoelectronic receivers and emitters. The optical packaging issues were addressed through a conventional coupling technique using a ball lens first. The die device performances were evaluated and compared with a packaged module in terms of frequency response, noise and nonlinearities. Since performances are usually measured as link performances we proposed a definition of the Opto-microwave figures of merit, such as Opto-microwave gain, noise, nonlinearities and EVM. They are presented and integrated into behavioral models, allowing both the individual performances extraction and system design. The integration of the RoF module in the system is the final part of this thesis. The performances were measured and simulated at each integration step. The final demonstrator based on the multipoint-to-multipoint architecture was implemented using an optoelectronic central node for the signal repartition and the Green Box for signal controlling. Real-time bidirectional transmission between two commercial WirelessHD devices at ~3 Gbit/s was validated. In a final section directions to improve VCSEL and SiGe HPT are explored. 25 GHz analogue VCSELs are explored with a focus on their dimensions, improved access and the potential of a suited matching approach. A novel collective and passive optical coupling technology is also proposed for both VCSEL and top illuminated detectors that couple smaller and faster devices
El-Huni, Walid. "Modélisation de cellules solaires multi-tandem bas coût et très haut rendement à base de nitrures des éléments III-V". Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS296/document.
Texto completo da fonteNitrides of III-V elements, have been widely studied because of their interessting applications in the LED light-emitting diodes, laser diodes and photodetectors. The bandgap of such ternary or quaternary alloys can be adjusted depending on the composition, at photon energies ranging from infrared to ultraviolet. This adjustable direct bandgap over a wide range, making these materials valuable for photovoltaic applications due to the possibility of inventing not only multi-junction solar cells at high efficiency, but also third generation solar cells such as cells with intermediate bandgap, based solely on nitrides alloys. In addition to their large adjustable bandgap, nitrides also show other interesting photovoltaic properties, such as low effective masses of the charge carriers, high mobility, high absorption coefficient and a radiation tolerance. The technology of III-V nitrides has demonstrated its ability to grow high quality crystal structures and to manufacture optoelectronic devices, which confirm its potential for photovoltaic solar energy with very high efficiency. By incorporating this material with crystalline silicon junction, we can have a multijunction cell with very high efficiency with a competitive cost
Dias, Ferreira João Marcelo. "Silicium multicristallin de type N pour la fabrication de cellules solaires à bas coût et à rendement de conversion élevée". Aix-Marseille 3, 2010. http://www.theses.fr/2010AIX30069.
Texto completo da fonteMorea, Annalisa. "Étude des réseaux optiques translucides : évaluation de leur faisabilité et de leur intérêt économique". Paris, ENST, 2006. http://www.theses.fr/2006ENST0050.
Texto completo da fonteThe arrival and mastery of new optical transmission technologies and all-optical switching of signals in optical networks allow the introduction of transparency in the core network. In transparent networks, optical signals are not converted to electronic signals except when added or dropped. A translucent transport network is half way between an opaque network (systematic opto-electrical conversion at each node) and a transparent network. This type of network provides a trade-off between transparency and opacity and permits : Alleviate the need for opto-electrical devices without restricting either the length of connexions in the network or the wavelength constraint, assuring a balance between signal performance at reception and total network cost. Operation of the network independent of certain signal characteristics (bit rate, modulation, etc) making the network more adaptive to developments. These aspects make this type of network very attractive for providers, such as France Télécom. The goal of this thesis is to determine network feasibility and the advantages that could be brought to the backbone network. This study is original in the use of physical constraints linked to network dimensioning; these features are the main research axes of the present work
Choi, Jihoon. "Nanofils de SiC : de la croissance aux dispositifs associés". Phd thesis, Université de Grenoble, 2013. http://tel.archives-ouvertes.fr/tel-01061784.
Texto completo da fonteCheynet, De Beaupré Vincent. "Dispositifs à Faible Coût Appliqués à la Synthèse de Fréquences et à la Modulation FSK pour les Systèmes de Radiocommunication". Phd thesis, Université de Provence - Aix-Marseille I, 2008. http://tel.archives-ouvertes.fr/tel-00395267.
Texto completo da fonteTous les systèmes de communication modernes requièrent un signal périodique stable pour fournir une base de temps nécessaire à la synchronisation, à l'alignement des horloges d'échantillonnage, à la récupération d'horloge ou encore à la synthèse de fréquence. Le verrouillage de phase est une des principales techniques pour répondre à ces besoins.
L'enjeu de ce travail de thèse est de concevoir, réaliser et caractériser une boucle à verrouillage de phase capable de s'intégrer dans un système de télécommunication développé en partenariat entre la société STMicroelectronics et l'Institut Matériaux Microélectronique Nanosciences de Provence (IM2NP). Ce système faible coût, faible consommation, réalisé en technologie CMOS est destiné à des applications de type réseaux personnels sans fils. Des contraintes fortes en terme de surface silicium, consommation, réactivité de la boucle et de précision fréquentielle sont les éléments directeurs de la conception de cette PLL. La boucle réalisée devra être capable de fonctionner en synthétiseur de fréquence et en modulateur FSK. Une attention particulière sera portée à l'oscillateur contrôlé en tension, véritable coeur de la PLL proposée.
Bertrand, Thierry. "Difficultés d'implantation des dispositifs ABC/ABM : contribution à la constitution de savoirs actionnables à partir d'une recherche intervention". Nantes, 2001. http://www.theses.fr/2001NANT4017.
Texto completo da fonteCoulaud, Henri. "Discrimination automatique du sommeil et de 9 comportements chez le rat à l'aide de capteurs piézo-résistifs : mesure de leur coût énergétique". Paris 12, 1987. http://www.theses.fr/1987PA120046.
Texto completo da fonteDelaine, Florentin. "Étalonnage in situ de l'instrumentation bas coût pour la mesure de grandeurs ambiantes : méthode d'évaluation des algorithmes et diagnostic des dérives". Thesis, Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAX075.
Texto completo da fonteIn various fields going from agriculture to public health, ambient quantities have to be monitored in indoors or outdoors areas. For example, temperature, air pollutants, water pollutants, noise and so on have to be tracked. To better understand these various phenomena, an increase of the density of measuring instruments is currently necessary. For instance, this would help to analyse the effective exposure of people to nuisances such as air pollutants.The massive deployment of sensors in the environment is made possible by the decreasing costs of measuring systems, mainly using sensitive elements based on micro or nano technologies. The drawback of this type of instrumentation is a low quality of measurement, consequently lowering the confidence in produced data and/or a drastic increase of the instrumentation costs due to necessary recalibration procedures or periodical replacement of sensors.There are multiple algorithms in the literature offering the possibility to perform the calibration of measuring instruments while leaving them deployed in the field, called in situ calibration techniques.The objective of this thesis is to contribute to the research effort on the improvement of data quality for low-cost measuring instruments through their in situ calibration.In particular, we aim at 1) facilitating the identification of existing in situ calibration strategies applicable to a sensor network depending on its properties and the characteristics of its instruments; 2) helping to choose the most suitable algorithm depending on the sensor network and its context of deployment; 3) improving the efficiency of in situ calibration strategies through the diagnosis of instruments that have drifted in a sensor network.Three main contributions are made in this work. First, a unified terminology is proposed to classify the existing works on in situ calibration. The review carried out based on this taxonomy showed there are numerous contributions on the subject, covering a wide variety of cases. Nevertheless, the classification of the existing works in terms of performances was difficult as there is no reference case study for the evaluation of these algorithms.Therefore in a second step, a framework for the simulation of sensors networks is introduced. It is aimed at evaluating in situ calibration algorithms. A detailed case study is provided across the evaluation of in situ calibration algorithms for blind static sensor networks. An analysis of the influence of the parameters and of the metrics used to derive the results is also carried out. As the results are case specific, and as most of the algorithms recalibrate instruments without evaluating first if they actually need it, an identification tool enabling to determine the instruments that are actually faulty in terms of drift would be valuable.Consequently, the third contribution of this thesis is a diagnosis algorithm targeting drift faults in sensor networks without making any assumption on the kind of sensor network at stake. Based on the concept of rendez-vous, the algorithm allows to identify faulty instruments as long as one instrument at least can be assumed as non-faulty in the sensor network. Across the investigation of the results of a case study, we propose several means to reduce false results and guidelines to adjust the parameters of the algorithm. Finally, we show that the proposed diagnosis approach, combined with a simple calibration technique, enables to improve the quality of the measurement results. Thus, the diagnosis algorithm opens new perspectives on in situ calibration
Vogt-Schilb, Adrien. "Éléments sur la transition vers du capital bas carbone". Thesis, Paris Est, 2015. http://www.theses.fr/2015PESC1114/document.
Texto completo da fonteThis thesis shows that while greenhouse gases are a stock pollution that imposes a shadow carbon cost that increases over time, it may be socially desirable to invest now in the deployment of expensive emission-reduction measures. This results solely from taking into account inertia inherent to the accumulation of low-carbon capital, in the absence of any other market imperfection. This thesis also covers the choice of policy instruments that imperfect governments can use to ensure the market implement these investments. It suggests that if governments cannot commit credibly to a carbon price path, or cannot fully compensate the losers from the introduction of a carbon price, then sector-scale policy instruments that incentivize investment in clean capital may be more effective and more acceptable than the carbon price
Devigne, Louise. "Solutions robotiques bas coût pour l’aide à la navigation en fauteuil roulant électrique : vers une contribution dans le champ de la rééducation neurologique". Thesis, Rennes, INSA, 2018. http://www.theses.fr/2018ISAR0024/document.
Texto completo da fonteWhile the use of a wheelchair allows people with disabilities to compensate for a loss of mobility, people with severe disabilities are denied the use of a power wheelchair. Indeed, cognitive or visual perception impairments can affect the ability to drive safely. In this context, access to mobility can be improved by providing appropriate assistive technologies to compensate for loss of mobility in all types of environments. While the first research on smart wheelchairs dates back to the early 1980s, no solutions have yet been proposed on the market or in rehabilitation centers and other specialized structures. This work aims to propose a set of solutions for power wheelchair navigation assistance designed in close collaboration with users and therapists. The development of such assistive solutions faces multiple robotic challenges combining innovative detection techniques, shared control with the user. In this work, a driving simulator supporting research and development of new robotic solutions for wheelchair navigation assistance is proposed. Then low-cost semi-autonomous assistance solutions for navigation assistance in indoor and outdoor environments are detailed. The evaluation with able-bodied participants allows to validate the mathematical methods and provide proof of concept of the proposed solutions. Finally, the first clinical evaluations with regular users at Pôle MPR Saint Hélier show the validation of the proposed framework in terms of user satisfaction
Thévenard, Julian. "Contribution à la conception à bas coût d'antennes 3D reconfigurables : solutions originales d'intégration en technologie plastique pour les systèmes sans fil du futur". Brest, 2008. http://www.theses.fr/2008BRES2011.
Texto completo da fonteThis thesis is dedicated to the design of 3D smart antennas for forthcoming wireless devices. Our research work has been motivated by the actual wireless trends leading to service concentration within WLAN and device miniaturisation. Thus, antenna design is nowadays guided by size constraints and their capacity to deal with fading interference, wireless environments while improving the performances of devices in terms of communication quality, power consumption. This thesis presents a multi-sector antenna solution associating many Vivaldi-antennas to provide a solution for the targeted application which is an embedded system constituting of high definition wireless cameras. A theoretical analysis of the Vivaldi antenna is first performed and then a novel concept of multi-sector antenna has been introduced and validated. Then, in order to target consumer market and to reduce the manufacturing costs in high volume production, the metallized molded plastic technology which enables molding 3D complex structures has been retained. An original without-welding transfer system has been developed for integrating the antenna to the rest of the system. The characterization of a prototype has resulted in the validation of the use of plastics for such applications. This antenna has been integrated in a wireless camera ; a protective radome having as additional property to improve the overall performances of the device is finally designed. This simplified integration procedure associated to a monitoring of the performances and the flexibility of the system makes it a good candidate for various applications like domestic WLAN, mesh networks or for MIMO technology
Pibouleau, Leslie. "Modèle d'analyse bayésien pour l'évaluation de dispositifs médicaux implantables : prise en compte de l'information disponible sur les versions antérieures du dispositif". Paris 7, 2013. http://www.theses.fr/2013PA077070.
Texto completo da fonteUnlike drugs, most implantable medical devices (IMD) are frequently updated by successive introductions of technical changes into new versions. The question that may arise is how to use the clinical data available on previous versions when evaluating the latest version of an IMD. The objective of our study was to propose a Bayesian approach that allows taking into account clinical data on earlier versions and experts' opinion in the estimation of the success rate of the latest version of an IMD. Our illustrative example was an intracranial stent used to treat wide-necked aneurysms and that comprised four versions. The proposed statistical model was a Bayesian hierarchical meta-analysis model that allowed to combining all of the trial results while explicitly modelling the heterogeneity between IMD versions in addition to the heterogeneity between individual studies. First, we studied the performances of this model compared to those of a standard random-effects model (i) to detect a version effect and (ii) to estimate the success rate of the latest version. Secondly, we developed a practical internet-based method for eliciting experts' belief about the success rate of the intracranial stent and we assessed its impact in the assessed benefit of the latest version of the device when only a small amount of data are available
Jacob, Steve. "L'institutionnalisation de l'évaluation des politiques publiques en Europe: étude comparée des dispositifs institutionnels en Belgique, en France, en Suisse et aux Pays-Bas". Doctoral thesis, Universite Libre de Bruxelles, 2004. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211091.
Texto completo da fonteMorbioli, Giorgio Gianini. "Funcionalização de celulose para ensaios bioanalíticos em dispositivos microfluídicos baseados em papel (μPADs)". Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-23062015-105938/.
Texto completo da fonteFunctionalization of a cellulosic matrix is essential for the success of the paper-based microfluidic analytical devices (µPADs). It allows minimization of sample preparation and user interference, both being major sources of errors in the analytical process. Cellulose oxidation with sodium m-periodate during one hour and the direct chemical immobilization of enzymes on it by Schiff-base (imines) formation, which is made by direct insertion of the enzyme on the oxidized substrate without subsequent steps, is a fast and low cost process of immobilization, presenting great potential of application in paper-based microfluidic analytical devices. The glucose oxidase enzyme immobilized on cellulose, with the addition of trehalose stabilizer presented enhanced catalytic activity - from 31.9 ± 5.5 mmol L-1 for the non-immobilized enzyme to 14.8 ± 2.0 mmol L-1 for the immobilized enzyme with the stabilizing agent - also presenting greater signal homogeneity, which are ideal characteristics in a paper-based rapid test. Wax printing is a simple, inexpensive and fast method by which micro-devices can be fabricated. Additionally, the stacking of layers originating tridimensional devices (3D) allow for the improvement of functionalities of 2-dimensional ones, such as individualized layer treatment and reagent storage at different layers in the same device. Standard addition to analytical curves in paper-based microchips is an alternative to external analytical curves, minimizing handling/sample preparation. The use of 2,2\'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid - ABTS redox indicator with the enzymatic reactions and the standard addition method in µPADs presented a good correlation in a growth and saturation Michaelis-Menten model (r2 = 0.8723), in the range of 0 to 10 mmol L-1, and the usage of the linear range to the glucose quantification (0 to 3 mmol L-1) presented a high linear correlation with the estimated concentration from the standard addition curves (r2 = 0.959), showing the potentiality of the method. The coupling of such paper-based devices to automated image analysis software, such as \'PAlizer\', turns the data acquisition process instantaneous, eliminating the need of human intervention during the process, making it more robust, reproducible and rapid. Expectations lie in improving the devices functions and potential so that these low-cost diagnostic devices can one day reach those who need them, contributing significantly to public health.
Mobarek, Iyad. "Conception d'un système national des équipements médicaux automatiques pour améliorer la performance et réduire les coûts d'investissements et d'exploitations des dispositifs médicaux". Compiègne, 2006. http://www.theses.fr/2006COMP1623.
Texto completo da fonteThis thesis describes the different phases of developing, implementing and evaluating a unique Clinical Engineering System (CES) based on Jordan. This includes establishing and then automating ail technical issues and information related to medical equipment in 29 hospitals, 685 health centers, 332 dental clinics, 348 pediatric and mother care clinics and 23 blood banks. Every medical equipment was assigned an identity code that can be recognized through a bar code scanning system and similarly ail other involved parameters like hospitals, personnel, spare parts, workshops. . . Etc. Are also coded comprehensively. The fully automated CES presents a powerful system; implemented over network covering different locations of the Directorate of Biomedical Engineering (DBE) at Ministry Of Heath ail over the country, presenting the first Comprehensive CES to be implemented on the national level and the automated system can read and report in both Arabic and English languages. Compared to international figures the developed clinical engineering system has enhanced the performance of medical equipment including its availability (uptime) up to the best available international levels at extremely low cost. The complete system proved to be invaluable tool to manage, control and report all different parameters concerning medical equipment in the considered clinical engineering system. The System was evaluated and found to be reliable, effective and unique compared to internationally available systems and it presents a. Successful model for other countries
Parment, Frédéric. "Guides d’onde Intégrés au Substrat (SIW) multicouches à haute performance pour des circuits millimétriques à faible coût". Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAT077/document.
Texto completo da fonteThe substrate integrated waveguide (SIW) technology, introduced in the early 2000s, has presently trigged a huge interest from academia to industry with the focus on the design and development of low-loss, compact, integrated, self-packaged and low-cost microwave and millimeter-wave circuits, antennas and systems. However, the classical metallic waveguide technology, which offers better performances such as lower insertion loss and higher power handling, has still been used in the design of microwave and millimeter-wave systems, despite its higher cost and bulky structure. To offer a highly integrated, further loss-reduced, low-cost alternative to the conventional waveguide and also to allow a wide-spread use of the millimeter-wave spectrum, this thesis research introduces a new SIW structure called Air-Filled SIW (AFSIW). This new structure has been theoretically and experimentally studied in details with a substantial amount of results. At millimeter wave frequencies, compared to the SIW topologies, the proposed AFSIW scheme exhibits a substantially lower insertion loss (three times, for example) and a much higher average power handling capability (four times, for example). Numerous AFSIW passive components have been investigated designed and demonstrated, which take advantages of the well-established multilayer printed circuit board (PCB) fabrication process. Couplers, phase shifters, power dividers, antennas and filters have been modeled, designed, prototyped and measured based on the introduced technology. Their performances have theoretically and experimentally been compared with their SIW counterparts to demonstrate and validate the benefits of the proposed technology
Faye, Oumoul khairy Aby. "Les papillons de cité : trajectoires scolaires et parcours socioprofessionnels d'un groupe de jeunes sans qualification au sein des dispositifs d'insertion : une étude de cas à Strasbourg". Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAG002.
Texto completo da fonteThis doctoral thesis deals with the socio-institutional trajectories of a group of youth with low-level qualifications or no qualifications at all, who benefit from a reinsertion policy measure designed to help them find job. The purpose of this research is to study how this target-group of youth – characterized by multiple forms of disqualifications – is getting the proposed support. First and foremost, it should be noted that those who have resorted to public assistance have been long wrongly considered a homogeneous social stratum, whereas indeed, there are several ways to deliver social support, depending on individuals, their different life experiences or even the specific phases they are go through by the time they ask for help. In line with this assertion, following the model of medical diagnosis, I undertook an“anamnesis” towards understanding, more or less, the etiological history of those male and female as well, finding themselves “ à posteriori” playing the institutionalized part of“pathological” trainees. From that point of view, I had to study different spaces that are namely : the family, the school and the institutional environment as well as their impacts on the socio-professional trajectories of the individuals concerned. In other words, the objective was to check to what extent, based on social supports received (nature, intensity, quality of resources ...), that youth may find the springs and dynamics allowing them to trace their own path.It is in this context that I integrated two associations active in social work towards facilitating the process of inserting young people having difficulties to enter the world of employment. Considered as communicational spaces, the “Mission Locale” and particularly “l’Atelier” were my privileged places of ethnographic observation, where I strived to single out the games of actors, power games, objectives and the multiple interactions entwined in these territories. A specific interest was put on personal experiences, perceptions, conflictual and /or cooperative interactions between social workers and beneficiaries. Jogging, basket (shoes), cap position (back / front) or street language, this field survey also allowed me to study the esthetics, postures and body expressions of young people by looking at the significance they take as individuals and / or collective action, particularly within social associations. In a broader prospect, I have tried to see how and to what extent the agents / actors of the social institutions take into account the specificities of this public and manage to create points of balance between the request of the beneficiaries and the institutional command, between imperatives as mediate and immediate structural constraints
Lallemand, Virginie. "Cryptanalyse de chiffrements symétriques". Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066657/document.
Texto completo da fonteThe main subject of this thesis is the security analysis of symmetric key ciphers. Specifically, we study several recently proposed block and stream ciphers and prove that the level of security stated by their designers is overestimated. The ciphers we study were all designed in order to meet the needs of one of the new applications of symmetric cryptography, which include symmetric ciphers for very constrained environments.The first part of the thesis is dedicated to the analysis of block ciphers with techniques based on differential cryptanalysis. We start with the description of a truncated differential attack on the family of lightweight ciphers KLEIN. Next, we analyse two ciphers that were designed in such a way that they could be easily and effectively protected against side-channel attacks: Zorro and Picaro. We show that the design choices made by their designers lead to weak diffusion properties. We exploit these imperfections to devise a differential cryptanalysis of Zorro and a related key attack on Picaro.The second part of this thesis deals with stream ciphers and gives an analysis of two innovative designs: Sprout and Flip. Sprout was designed in order to limit its hardware area size and to suit very constrained environments, while Flip reaches efficient performances when used in FHE schemes. In both cases, we find flaws that lead to attacks of the particular set of parameters proposed for these ciphers
Fischer, Marie. "Élaboration in situ d’alliages de titane et de structures architecturées par fabrication additive : application aux dispositifs médicaux implantables". Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0257/document.
Texto completo da fonteThe initial problematic arises from the fact that implant failure is often caused by a mismatch between the elastic properties of the bone and those of the implant. Nowadays, an increasing interest is given to this mechanical biocompatibility and led to the development of β-metastable titanium alloys that possess low Young’s modulus, about half that of the conventionally used Ti-6Al-4V alloy. Moreover, lattice structures are currently being the subject of many investigations with the aim of achieving low Young’s modulus and high strength. Their fabrication, with accurate control over the architecture, is made possible thanks to additive manufacturing processes and the several possibilities they offer: design freedom, reduced material usage rate, complex shapes, mass customisation... The present work focuses on the implementation of low modulus titanium alloy Ti-26Nb(at.%) by the means of selective laser melting. An in situ elaboration strategy, based on a mixture of elemental powders, is explored in order to allow potential composition adjustments and to overcome the unavailability of titanium alloy powders. The approach is carried out using two distinct powder morphologies, spherical and irregular. The effects of the numerous parameters of the process (laser power, speed, scanning strategy...) on homogeneity and porosity of the manufactured parts is quantified. A homogeneous alloy can be obtained subject to the use of suitable energy density levels and powder size distributions that take into account the respective fusion temperatures of both elements. Microstructure characterisation highlights a pronounced texture resulting from the scanning strategy. The elaborated samples display a low Young’s modulus associated with a high strength, and hence a favourable strength to elastic modulus ratio compared to the reference cast alloy. Furthermore, an optimization algorithm is developed and allows controlling the mechanical properties of a lattice structure with its geometrical parameters (radius, length and orientation of struts). The combined use of this low Young’s modulus titanium alloy with a lattice structure developed through this algorithm was applied to the design of a total hip prosthesis that was subjected to finite element simulations. Stress-shielding evaluation shows that, compared to a solid design, this kind of prosthesis permits to reduce stress-shielding significantly. By getting closer to a physiological model, this prosthesis can be qualified as “biomimetic” in terms of mechanical behaviour
Lallemand, Virginie. "Cryptanalyse de chiffrements symétriques". Electronic Thesis or Diss., Paris 6, 2016. http://www.theses.fr/2016PA066657.
Texto completo da fonteThe main subject of this thesis is the security analysis of symmetric key ciphers. Specifically, we study several recently proposed block and stream ciphers and prove that the level of security stated by their designers is overestimated. The ciphers we study were all designed in order to meet the needs of one of the new applications of symmetric cryptography, which include symmetric ciphers for very constrained environments.The first part of the thesis is dedicated to the analysis of block ciphers with techniques based on differential cryptanalysis. We start with the description of a truncated differential attack on the family of lightweight ciphers KLEIN. Next, we analyse two ciphers that were designed in such a way that they could be easily and effectively protected against side-channel attacks: Zorro and Picaro. We show that the design choices made by their designers lead to weak diffusion properties. We exploit these imperfections to devise a differential cryptanalysis of Zorro and a related key attack on Picaro.The second part of this thesis deals with stream ciphers and gives an analysis of two innovative designs: Sprout and Flip. Sprout was designed in order to limit its hardware area size and to suit very constrained environments, while Flip reaches efficient performances when used in FHE schemes. In both cases, we find flaws that lead to attacks of the particular set of parameters proposed for these ciphers
Nascimento, Thiago Mazzú do. "Plataformas de baixo custo à base de papel para testes imunodiagnósticos e enzimáticos". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/75/75133/tde-13032017-090102/.
Texto completo da fonteImmunoassays and bioassays are broadly used in clinical medicine. Paper-based devices are ideal to be used in remote regions due to their low-cost, portability and the possibility of in loco manufacture. Paper-based immunoassays are extremely versatile, capable of detecting distinct analytes: initially we have developed an immunochromatographic assay to detect rabbit IgG in a paper-based device fabricated using wax printing technology, and we have shown that this prototype has potential to be applied in distinct immunoassays. The second developed paper-based device was an enzymatic colorimetric assay for the detection of a potential prostate cancer biomarker - sarcosine (sarcosine oxidase, peroxidase and redox indicator (ABTS)), obtaining good figures or merit (LOD = 0.21 mmol L-1; LOQ = 0.61 mmol L-1, r² = 0.890). The third developed paper-based device was capable of detecting toxoplasmosis (IgG against Toxoplasma gondii in human serum samples). The performance evaluation showed a cut-off = 21.73 A.U., sensitivity = 0.96, specificity = 0.87, AUC = 0.97, besides defining the gray zone as the zone comprehended in-between 15% over the cut-off value. We also have developed a Microsoft Excel® macro to calculate diagnostic test\'s accuracy - m-Accuracy - that is a new way to calculate accuracy with great innovation for clinical medicine, which resulted in an accuracy of 0.88. for toxoplasmosis assay. The fourth developed paper-based device was used to detect CEA tumor biomarker using a sandwich ELISA assay, with a cut-off = 68.28 A.U., sensitivity = 0.86, specificity = 1.0, AUC = 0.97. The defined gray zone to this test was the zone comprehended in-between 12% over the cut-off value, with an accuracy of 0.90. To the best of our knowledge, this is the first complete statistical evaluation of paper-based diagnostic devices, which showed the great potential of this technology to be used as a new point-of care diagnostic tool.
Schrottenloher, André. "Quantum Algorithms for Cryptanalysis and Quantum-safe Symmetric Cryptography". Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS271.
Texto completo da fonteModern cryptography relies on the notion of computational security. The level of security given by a cryptosystem is expressed as an amount of computational resources required to break it. The goal of cryptanalysis is to find attacks, that is, algorithms with lower complexities than the conjectural bounds.With the advent of quantum computing devices, these levels of security have to be updated to take a whole new notion of algorithms into account. At the same time, cryptography is becoming widely used in small devices (smart cards, sensors), with new cost constraints.In this thesis, we study the security of secret-key cryptosystems against quantum adversaries.We first build new quantum algorithms for k-list (k-XOR or k-SUM) problems, by composing exhaustive search procedures. Next, we present dedicated cryptanalysis results, starting with a new quantum cryptanalysis tool, the offline Simon's algorithm. We describe new attacks against the lightweight algorithms Spook and Gimli and we perform the first quantum security analysis of the standard cipher AES.Finally, we specify Saturnin, a family of lightweight cryptosystems oriented towards post-quantum security. Thanks to a very similar structure, its security relies largely on the analysis of AES