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1
Ryan, James. "Organic and hybrid optoelectronic devices: understanding key loss mechanisms." Doctoral thesis, Universitat Rovira i Virgili, 2013. http://hdl.handle.net/10803/285966.
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This thesis sets to understand key limiting steps in organic solar cells (OSCs) and hybrid organic-inorganic light-emitting diodes (HyLEDs) and to provide routes to more environmentally friendly and lower cost devices. As well as studying organic optoelectronic devices, hybrid organic-inorganic approaches are also explored from both a fundamental point of view (quantum dot/organic solar cells) to a more technological one (air-stable, low cost light emitting diodes). The origin of the opencircuit voltage in bilayer solar cells is studied using transient optoelectronic techniques to probe the charge distribution in the active layer and the lifetime of charge carriers under working conditions. Furthermore, these techniques are applied to hybrid quantum dot/organic bilayer solar cells and provide a quantitative analysis of the non-geminate recombination in the device and its influence on the open-circuit voltage. The thesis also explores the use of water-soluble donors for OSCs and led to first true water-soluble donor.Este trabajo de tesis proporciona las bases para el análisis detallado de los pasos limitantes del funcionamiento de celdas solares orgánicas (OSCs) y de los lightemitting diodos híbridos orgánico-inorgánicos (HyLED); además de procurar las rutas para la preparación de nuevos tipos de dispositivos económicos y seguros para el medio ambiente. El origen del voltaje de circuito abierto en celdas solares de doble capa ha sido estudiado mediante técnicas de optoelectrónica transientes para investigar la distribución de cargas en el estado activo y los tiempos de vida de las cargas bajo las condiciones de trabajo. Además, estas técnicas han sido aplicadas a celdas solares híbridas quantum dots/doble capa orgánica consiguiendo un análisis cuantitativo de la recombinación no-geminial en el dispositivo y su influencia sobre el voltaje de circuito abierto. La tesis también explora el uso de donantes solubles en agua para OSCs y llevó al primer verdadero donante soluble en agua.
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Boyd, Steven J. "Hybrid Electric Vehicle Control Strategy Based on Power Loss Calculations." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/34970.
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Defining an operation strategy for a Split Parallel Architecture (SPA) Hybrid Electric Vehicle (HEV) is accomplished through calculating powertrain component losses. The results of these calculations define how the vehicle can decrease fuel consumption while maintaining low vehicle emissions. For a HEV, simply operating the vehicle's engine in its regions of high efficiency does not guarantee the most efficient vehicle operation. The results presented are meant only to define a literal strategy; that is, an understanding as to why the vehicle should operate in a certain way under the given conditions. The literature review gives a background of hybrid vehicle control publications, and without the SPA HEV addressed or a hybrid analysis based on loss calculations between engine only and hybrid modes, there is a need for this paper. Once the REVLSE architecture and components are understood, the hybrid modes are explained. Then the losses for each hybrid mode are calculated, and both the conversion and assist efficiencies are detailed. The conversion efficiency represents the amount of additional fuel required to store a certain amount of energy in the battery, and this marginal efficiency can be higher than peak engine efficiency itself. This allows electric only propulsion to be evaluated against the engine only mode, and at low torques the electric motor is more efficient despite the roundtrip losses of the hybrid system.Master of Science
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Dongmo, Jean Etienne Temgoua Kwatny Harry G. "Aircraft loss-of-control prevention and recovery : a hybrid control strategy /." Philadelphia, Pa. : Drexel University, 2010. http://hdl.handle.net/1860/3252.
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Chapa, Gordero Felisa. "Polarization Dependent Loss (PDL) in Polarization Multiplexed and Hybrid Optical Networks." Thesis, Norwegian University of Science and Technology, Department of Electronics and Telecommunications, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9528.
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Study of the Polarization Dependent Loss caused by the combined effect of orthogonality degradation and dynamic power fluctuations in a hybrid network, which combines circuit switching with packet switching to transmit applications with very different quality requirements on the same wavelength channel.
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Bilen, Cagdas. "A Hybrid Approach For Full Frame Loss Concealment Of Multiview Video." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608559/index.pdf.
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Multiview video is one of the emerging research areas especially among the video coding community. Transmission of multiview video over an error prone network is possible with efficient compression of these videos. But along with the studies for efficiently compressing the multiview video, new error concealment and error protection methods are also necessary to overcome the problems due to erroneous channel conditions in practical applications.
In packet switching networks, packet losses may lead to block losses in a frame or the loss of an entire frame in an encoded video sequence. In recent years several algorithms are proposed to handle the loss of an entire frame efficiently. However methods for full frame losses in stereoscopic or multiview videos are limited in the literature.
In this thesis a stereoscopic approach for full frame loss concealment of multiview video is proposed. In the proposed methods, the redundancy and disparity between the views and motion information between the previously decoded frames are used to estimate the lost frame. Even though multiview video can be composed of more than two views, at most three view are utilized for concealment. The performance of the proposed algorithms are tested against monoscopic methods and the conditions under which the proposed methods are superior are investigated. The proposed algorithms are applied to both stereoscopic and multiview video.
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U-yen, Kongpop. "Microwave filters with high stop-band performance and low-loss hybrid developement." Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-11162006-111102/.
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Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2007.Tentzeris, Manos, Committee Member ; Wollack, Edward, Committee Member ; Cressler, John, Committee Member ; Papapolymerou, Ioannis, Committee Chair ; Laskar, Joy, Committee Co-Chair ; Ayazi, Farrokh, Committee Member.
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Johnson, Eric K. "Low Loss Hybrid Waveguide Electric Field Sensor Based on Optical D-fiber." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2153.pdf.
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Araci, Ismail E. "LOW-LOSS, HIGH PERFORMANCE HYBRID PHOTONICS DEVICES ENABLED BY ION-EXCHANGED GLASS WAVEGUIDES." Diss., The University of Arizona, 2010. http://hdl.handle.net/10150/195837.
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Robust ion-exchanged glass waveguides exhibit low optical losses in a broad spectral range and they allow integration of several devices on the same chip due to their planar structure. Consequently, they can be a low cost alternative to semiconductors for fabricating various integrated optical devices. Two high performance photonic devices were designed and realized, demonstrating the potential of glass waveguides. The well-controlled silver-film ion-exchange process allowed the fabrication of: i) a highly sensitive biosensor based on optical absorption and, ii) a low loss hybrid electro-optic (EO) polymer modulator with a narrow coplanar electrode gap. The single-mode, channel integrated optical ion-exchange waveguide on borosilicate glass (Corning 0211) is described for broad spectral band (400-650 nm) detection and analysis of heme-containing protein films at a glass/water interface. The evanescent wave interaction is improved significantly by fabricating ion-exchange waveguides with a step-like index profile. Silver nano-particle formation is reduced in order to achieve low loss in the Soret-band (~400 nm). Unlike other surface-specific techniques (e.g. SPR, interferometry) that probe local refractive-index changes and therefore are susceptible to temperature fluctuations, the integrated optical waveguide absorption technique probes molecular-specific transition bands and is expected to be less vulnerable to environmental perturbations. The hybrid integration of phosphate glass (IOG-1) and EO polymer is realized for the first time. The critical alignment steps which are typically required for hybrid optoelectronic devices are eliminated with a simple alignment-free fabrication technique. The low loss adiabatic transition from glass to EO polymer waveguide is enabled by gray scale patterning of the novel EO polymer, AJLY. Total insertion loss of 5 dB and electrode gap of 8 μm is obtained for an optimized device design. EO polymer poling at 135 ºC and 75 V/μm is enabled by the sol-gel buffer layer.
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Baker, Jose Enrique. "Measurements of leakage, power loss and rotordynamic force coefficients in a hybrid brush seal." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2767.
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Zhao, Yue. "Automatic Prevention and Recovery of Aircraft Loss-of-Control by a Hybrid Control Approach." Ohio University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1458728101.
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Williams, Paul Timothy. "Acoustic performance of dissipative and hybrid silencers in ducts with large transverse dimensions." Thesis, Brunel University, 2015. http://bura.brunel.ac.uk/handle/2438/13745.
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Numerical models will be developed for the prediction of silencer transmission loss under the operating conditions present in gas turbine exhausts. In these systems the large diameter ducts and high operating temperatures produce a challenging acoustic environment due to the unverified behaviour of fibrous materials at high temperatures and the existence of complex sound fields. To understand the behaviour of fibrous materials at high temperatures their bulk acoustic properties are measured using a modified impedance tube which can heat material samples up to a temperature of 500 C. It will be demonstrated that the high temperature material properties can be extrapolated from room temperature measurements given knowledge of the temperature dependant flow resistivity. Finite element numerical models using point collocation and mode matching techniques to predict the transmission loss of silencers are developed and successfully validated. Dissipative silencer designs with various cross-sectional designs are explored numerically and experimentally according to common industry standards. It is demonstrated that transmission loss may be optimised by the arrangement of the fibrous material across the cross-section. The accurate numerical models allow for effe cient silencers to be designed reducing silencer size and cost. A new hybrid silencer is presented combining dissipative and reactive elements with the aim of increasing the low frequency attenuation of large silencers while maintaining an effective broadband spectrum. Measurements and predictions show this innovative design to be successfull. Application of the hybrid silencer allows for more flexible noise control solutions when design is limited by low frequency noise.
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Johnson, Kurt M. "A Plug-in Hybrid Electric Vehicle Loss Model to Compare Well-to-Wheel Energy Use from Multiple Sources." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/33968.
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Hybrid electric vehicles (HEV) come in many sizes and degrees of hybridization. Mild hybrid systems, where a simple idle stop strategy is employed, eliminate fuel use for idling. Multiple motor hybrid systems with complex electrically continuously variable transmissions in passenger cars, SUVs and light duty trucks have large increases in fuel economy. The plug-in hybrid electric vehicle (PHEV) takes the electrification of the automobile one step further than the HEV by increasing the battery energy capacity. The additional capacity of the battery is used to propel the vehicle without using onboard fuel energy. Commercial software of great complexity and limited availability is often used with sophisticated models to simulate powertrain operation. A simple method of evaluating technologies, component sizes, and alternative fuels is the goal of the model presented here. The objective of this paper is to define a PHEV model for use in the EcoCAR competition series. E85, gaseous hydrogen, and grid electricity are considered. The powertrain architecture selected is a series plug-in hybrid electric vehicle (SPHEV). The energy for charge sustaining operation is converted from fuel in an auxiliary power unit (APU). Compressed hydrogen gas is converted to electricity via the use of a fuel cell system and boost converter. For E85, the APU is an engine coupled to a generator. The results of modeling the vehicle allow for the comparison of the new architecture to the stock vehicle. In combination with the GREET model developed by Argonne National Lab, the multiple energy sources are compared for well to wheel energy use, petroleum energy use, and greenhouse gas emissions.Master of Science
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SCHUTZMANN, STEFANO. "Towards hybrid sol-gel devices for optoelectronic biosensors." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2006. http://hdl.handle.net/2108/202687.
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I sensori per la rilevazione di sostanze inquinanti in acqua, terra e atmosfera così come i dispositivi biosensori per l’identificazione di proteine ed enzimi, rappresentano un interessantissimo ambito di ricerca con forti applicazioni in campo industriale. In questo contesto, una promettente possibilità è rappresentata dallo sviluppo di sensori basati sull’optoelettronica dato che essi assicurano un’alta sensibilità, una buona stabilità meccanica, la possibilità di miniaturizzare i dispositivi e di produrli su larga scala. In particolare, negli ultimi anni molti sforzi sono stati orientati allo sviluppo di sensori ottici a guida d’onda. Il principio di funzionamento di questo tipo di dispositivi è basato sull’interazione fra la componente del campo evanescente di un’onda guidata e la regione che si vuole analizzare.
Lo sviluppo di dispositivi optoelettronici, d’altra parte, richiede la possibilità di sintetizzare materiali dalle qualità ottiche appropriate. In particolare, la possibilità di cambiare opportunamente l’indice di rifrazione rappresenta un aspetto fondamentale per la fabbricazione di dispositivi reali. I materiali ibridi organico-inorganici sintetizzati con la tecnologia sol-gel rappresentano una valida alternativa ai più tradizionali metodi per la fabbricazione di dispositivi ottici integrati come la tecnica dello scambio ionico o la CVD (chemical vapor deposition). Questa tecnica ibrida permette lo sviluppo di materiali dalle caratteristiche nuove in modo semplice ed economico.
La presente tesi tratta dello sviluppo, della sintesi e della caratterizzazione di guide d’onda sol-gel ibride per possibili applicazioni come sensori ottici a guida d’onda.
La caratterizzazione ottica dei dispositivi è stata effettuata principalmente utilizzando un apparato sperimentale sviluppato ed ottimizzato dal candidato durante il primo periodo del lavori di dottorato. Il setup si basa sia sulla tecnica m-line sia sulla tecnica dell’angolo di Brewster e rappresenta uno strumento semplice e a basso costo per l’analisi dell’indice di rifrazione di film sottili. I risultati mostrano che l’apparato permette la stima dell’indice di rifrazione a diverse lunghezze d’onda nel visibile e nel vicino infrarosso di film aventi spessore da poche decine di nanometri a diversi micron. L’errore nella determinazione dell’indice di rifrazione è compreso nel range ±0.001-0.003 a seconda della lunghezza d’onda e delle proprietà del campione. L’ottima accuratezza e affidabilità del nostro apparato è anche confermata dal confronto con i risultati ottenuti da misure di ellissometria spettroscopica.
Molti sforzi sono stati indirizzati alla sintesi e caratterizzazione di diverse guide d’onda sol-gel deposte su substrati sia di vetro che di silicio. I campioni sono stati caratterizzati mediante misure di indice di rifrazione di perdite ottiche usando la tecnica dell’analisi della luce di scattering. I risultati hanno mostrato la possibilità di modulare l’indice di rifrazione fra 1.45 e 1.90 semplicemente modificando la sintesi chimica e i trattamenti post-deposizione. Perdite di propagazione dell’ordine di 3-10 dB/cm sono state misurate sui nostri campioni a seconda della lunghezza d’onda, della polarizzazione del modo selezionato. Questi valori sono piuttosto comuni per guide d’onda planari di tipo sol gel ibrido.
Durante questo lavoro sono state inoltre sintetizzate a caratterizzate guide d’onda drogate con molecole luminescenti al fine di mostrare la possibilità di usare le nostre strutture guidanti come dispositivi attivi. Si è investigata anche l’opportunità di modulare l’indice di rifrazione di film ibridi utilizzando le proprietà di molecole fotosensibili esposte a luce ultravioletta.
Infine, l’ultimo periodo di tesi è stato dedicato con successo ad investigare la possibilità di utilizzare la guide d’onda sol-gel ibride come strutture-base per lo sviluppo di sensori ottici a fluorescenza. A tal fine sono state condotte misure di fluorescenza eccitata mediante onda evanescente.Environment sensors for the detection of polluting substances in water, earth and atmosphere as well as biosensor devices for the recognition of proteins and enzymes represent a very intriguing topic for both research and industrial applications. In this framework, a very promising alternative is represented by the development of sensors based on optoelectronic technology since they combine high sensitivity, mechanical stability, miniaturization and the possibility of mass-production. In particular, extensive research have been devoted to evanescent-field-based optical waveguide sensors. The operation principle of this kind of devices is based on the interaction between the evanescent field component of a guided optical wave and the monitoring region. The development of optoelectronic devices requires the possibility to design materials with suitable optical properties. In particular, the possibility of changing appropriately the refractive index represents a fundamental step for design and fabrication of real devices. Hybrid organic-inorganic materials synthesized by sol-gel technology seem to be a valid alternative to more traditional methods such as ion exchange or chemical vapor deposition for fabrication of integrated optical devices. Hybrid materials combining organic and inorganic networks allow the design and fabrication of new materials with appropriate features in a simple and economic way. This thesis reported on the design, synthesis and characterization of hybrid sol-gel-based waveguides for possible applications as fluorescence-based optical sensors. Optical characterization has been accomplished using a home-made experimental setup built and optimized by the candidate during the first period of the PhD fellowship. The setup is based on both m-line and Brewster methods and represents a completely non-destructive, low cost and very simple tool for thin film refractive index estimation. Results have shown that the apparatus allows the estimation of refractive index at different wavelengths in the visible and near infrared spectral region for films having thickness from few tens of nanometers to several micrometers. The error in refractive index determination was in the range ±0.001-0.003, depending on wavelength and sample features. Comparison with results obtained by ellipsometric measurements have confirmed the high accuracy and reliability of our setup. Many efforts was dedicated to the synthesis and characterization of different hybrid sol-gel waveguides grown both on silicon and glass substrates. Samples were characterized by refractive index determination and propagation loss measurements using scattered light detection technique. Results have shown the possibility to modulate quite easily the refractive index from 1.45 to about 1.90 playing on the chemical synthesis and on the post-deposition treatments. Propagation loss coefficients in the range 3-10 dB/cm were commonly obtained on our samples, depending on wavelengths, polarization, and mode selected. These values are quite common for planar organic/inorganic sol-gel based waveguides. Waveguides doped with fluorescent molecules were synthesized and characterized showing the possibility to use our structures as active optical devices. The modulation of refractive index of hybrid films using photosensitive molecules was investigated exposing films to different UV light dose. Moreover, first efforts to fabricate channel waveguides exploiting photolithographic techniques were accomplished. Finally, the possibility to use hybrid sol-gel planar waveguides as building blocks for a fluorescence-based optical sensor has been demonstrated performing measurements of fluorescence excited by guided wave evanescent field.
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Halbach, Till. "Error-robust coding and transformation of compressed hybered hybrid video streams for packet-switched wireless networks." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Information Technology, Mathematics and Electrical Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-136.
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This dissertation considers packet-switched wireless networks for transmission of variable-rate layered hybrid video streams. Target applications are video streaming and broadcasting services. The work can be divided into two main parts.
In the first part, a novel quality-scalable scheme based on coefficient refinement and encoder quality constraints is developed as a possible extension to the video coding standard H.264. After a technical introduction to the coding tools of H.264 with the main focus on error resilience features, various quality scalability schemes in previous research are reviewed. Based on this discussion, an encoder decoder framework is designed for an arbitrary number of quality layers, hereby also enabling region-of-interest coding. After that, the performance of the new system is exhaustively tested, showing that the bit rate increase typically encountered with scalable hybrid coding schemes is, for certain coding parameters, only small to moderate. The double- and triple-layer constellations of the framework are shown to perform superior to other systems.
The second part considers layered code streams as generated by the scheme of the first part. Various error propagation issues in hybrid streams are discussed, which leads to the definition of a decoder quality constraint and a segmentation of the code stream to transmit. A packetization scheme based on successive source rate consumption is drafted, followed by the formulation of the channel code rate optimization problem for an optimum assignment of available codes to the channel packets. Proper MSE-based error metrics are derived, incorporating the properties of the source signal, a terminate-on-error decoding strategy, error concealment, inter-packet dependencies, and the channel conditions. The Viterbi algorithm is presented as a low-complexity solution to the optimization problem, showing a great adaptivity of the joint source channel coding scheme to the channel conditions. An almost constant image qualiity is achieved, also in mismatch situations, while the overall channel code rate decreases only as little as necessary as the channel quality deteriorates. It is further shown that the variance of code distributions is only small, and that the codes are assigned irregularly to all channel packets.
A double-layer constellation of the framework clearly outperforms other schemes with a substantial margin.
Keywords — Digital lossy video compression, visual communication, variable bit rate (VBR), SNR scalability, layered image processing, quality layer, hybrid code stream, predictive coding, progressive bit stream, joint source channel coding, fidelity constraint, channel error robustness, resilience, concealment, packet-switched, mobile and wireless ATM, noisy transmission, packet loss, binary symmetric channel, streaming, broadcasting, satellite and radio links, H.264, MPEG-4 AVC, Viterbi, trellis, unequal error protection
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Jaberansary, Ehsan. "New computational method to estimate the effect of roughness on scattering loss and its implementation in a hybrid heterojunction optical modulator." Thesis, University of Southampton, 2014. https://eprints.soton.ac.uk/368779/.
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In the past year, there has been an advancement in the development of optical active and passive Silicon-On-Insulator for Photonic Integrated Circuits (PICs) applications. Following the continuous miniaturisation trend in this technology the study of the loss performance of these devices also become an attractive subject. Among the many components silicon based optical modulators are specifically important for low loss and high bandwidth short reach interconnects. The general aim of this thesis is to design and computationally investigate the performance of a multilayer hybrid silicon modulator. The design involves a heterojunction structure that operates based on plasma dispersion effect taking the effect of surface roughness and scattering loss into account. For this purpose a novel numerical approach is developed to estimate scattering loss due to the roughness in general waveguide structures and also the proposed silicon based optical waveguide modulator in this work. The applicability can be however extended towards wider range of optical waveguide based devices including multilayer configurations. The method is based on 2D Fourier transform technique that is widely used in Magneto Resonance Imaging technique. Firstly, the effect of three forms of roughness is investigated in a general strip waveguide structure; isotropic, anisotropic and the mixture of isotropic and anisotropic. In each case the generated sidewall roughness is implemented in various SOI high contrast refractive index waveguides. The waveguide dimensions have been chosen to cover a large variety of waveguide sizes to evaluate the accuracy of the modelling technique. Two SOI waveguide samples have been fabricated. The first sample is 100nm, 1200nm and 1400nm in width and 500nm in height which are single mode in Mid Infra Red (MIR) region. The second sample contains waveguide with 220nm height and 330nm widths that is single mode in Near Infra Read (NIR) wavelength. Other dimensions are chosen from several published works. The calculated losses using FDTD show good agreement with all measured fabricated waveguide and the referred experimental works in the literature. The three dimensional model successfully explains the scattering loss dependence on the width of a high aspect ratio waveguide when the result is compared with a published work. While the measurement shows the loss reduces from 32dB/cm to 0.8dB/cm, the simulation results varies from 44dB/cm to 1dB/cm. The interdependence of scattering loss is also investigated against other theoretical approaches when the correlation length varies from 0 to 1000nm. The relatively low aspect ratio waveguide is chosen to have a fixed dimension of 220nm by 330nm and 5nm value. In order to study the scattering loss caused by roughness the roughness model is applied in the proposed modulator structure. The design involves a multimode strip like p doped silicon material wrapped by transparent ZnO as a naturally n doped active material. This forms a pn heterojunction that is implemented in one arm of a Mach Zehnder interferometer. The switch is designed to operate at 1.55µm and in depletion mode to avoid minority carrier life time effect in switching speed. The calculated capacitance switching speed of a pulse were less than 1 pf=cm and 90ps respectively. The resistivity v is higher compared to a general form of heterojunction due to the relativity larger ZnO/Si contact area of the device. The phase shifter is implemented in Mach Zehnder structure to change from phase modulation to amplitude modulation using a MMI structure. The calculated extinction ratio was as high as 23.7dB with the insertion loss of 2.5dB. Further simulation results shows that the 100nm change in the ZnO thickness can alter the effective index of refraction and loss performance of the devices. In an ideal situation, as the thickness increases from 50nm to 150nm the loss changes from 2 to 8dB/cm for TE mode. The involvement of sidewall roughness results higher insertion loss by at least by 0.2dB when the rms of the sidewall roughness increases by 7nm. As the ZnO coating thickness increases, the roughness effect is counterbalanced by almost 50%.
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Bakare, Adeyinka A. "A Methodology for Cyberthreat ranking: Incorporating the NIST Cybersecurity Framework into FAIR Model." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1583247043269043.
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Leung, Joseph, Michio Aoyagi, Donald Billings, Herbert Hoy, Mei Lin, and Fred Shigemoto. "A MOBILE RANGE SYSTEM TO TRACK TELEMETRY FROM A HIGH-SPEED INSTRUMENTATION PACKAGE." International Foundation for Telemetering, 1998. http://hdl.handle.net/10150/607380.
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International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, CaliforniaAs renewal interest in building vehicles based on hypersonic technologies begin to emerge again, test ranges anticipating in supporting flight research of these vehicles will face a set of engineering problems. Most fundamentals of these will be to track and gather error free telemetry from the vehicles in flight. The first series of vehicles will likely be reduced-scale models that restrict the locations and geometric shapes of the telemetry antennas. High kinetic heating will further limit antenna design and construction. Consequently, antennas radiation patterns will be sub-optimal, showing lower gains and detrimental nulls. A mobile system designed to address the technical issues above will be described. The use of antenna arrays, spatial diversity and a hybrid tracking system using optical and electronic techniques to obtain error free telemetry in the present of multipath will be presented. System tests results will also be presented.
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Kulhány, Andrej. "Zkoumání vlivu přítlaku na životnost olověných akumulátorů pro hybridní elektrická vozidla." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218570.
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The thesis is focused on remitting lead-acid segments of partial charge mode which simulates the conditions in HEV. The experimental cells were submitted to different pressures on the electrode system. The main aim of the thesis was to minimize the irreversible sulphating of the negative electrodes, which are in the PSoC regime limiting in the overall life of lead-acid accumulators. All cells were submitted to measurement of the negative electrode potentials, resistance of active materials, contact resistance of the grid – the active material and measurements of pressure changes during three PSoC cycles.
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Li, Li. "Etude et mise au point d'une nouvelle famille d'alterno-démarreur pour véhicules hybrides et électriques." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00639305.
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Les travaux de cette thèse portent sur une nouvelle structure de machine à double excitation (MSDE) pour l'application des véhicules hybrides et électriques. Ce type de machine, ayant deux sources d'excitation, bénéficie un degré de liberté supplémentaire et un contrôle facile sur le flux. Grâce à ce degré de liberté, la machine peut être dimensionnée de manière que son meilleur rendement coïncide avec la zone de fonctionnement la plus sollicitée de la machine. Cette nouvelle structure a fait l'objet principal de ce mémoire. Le fonctionnement de la MSDE est présenté dans les deux premiers chapitres. La machine est dimensionnée suivant un cahier des charges pour véhicule hybride. La validation expérimentale a confirmé le bon fonctionnement de la structure et montré son intérêt. Une autre problématique dans le dimensionnement de la machine est l'aspect thermique car les machines sont devenues de plus en plus compactes et puissantes. Une estimation correcte des pertes est indispensable pour évaluer correctement les performances de la machine. C'est la raison pour laquelle on a décidé de consacrer une partie de cette thèse à la modélisation des pertes fer, dont l'estimation n'est pas évidente.
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Foglia, Laura [Verfasser], Martin [Akademischer Betreuer] Wolf, Ulrike [Gutachter] Woggon, and Julia [Gutachter] Stähler. "Ultrafast dynamics and energy loss channels at a hybrid organic inorganic interface / Laura Foglia ; Gutachter: Ulrike Woggon, Julia Stähler ; Betreuer: Martin Wolf ; Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin." Berlin : Technische Universität Berlin, 2015. http://d-nb.info/1156012805/34.
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TEIXEIRA, MONTEIRO ANTONIO MANUEL. "ASSESSMENT OF ECOLOGICAL CONDITIONS OF PERMANENT MEADOWS IN THE ITALIAN ALPS: LOSS, BIODIVERSITY AND REMOTE SENSING CHANGE DETECTION." Doctoral thesis, Università degli Studi di Milano, 2011. http://hdl.handle.net/2434/152908.
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The monitoring of ecological condition of grasslands ecosystems in the
European Alps is a main issue for mountain regions, since the abandonment of
traditional and sustainable management practices has exposed grassland habitat
to significant impacts in a context of global environmental change.
The present research project was focused in assessment of the state of
permanent meadows in the lowlands of Valtellina Valley (80 km2), Italian Alps,
during the timeframe 1980-2000. In specific, it quantified the land use/land
cover changes and identified main drivers behind permanent meadows loss;
characterized the relationship between biodiversity in the meadows and the
spatial-environmental conditions in the landscape and by last evaluated the use
of satellite remote sensing data for fast change detection in landscape. To
achieve such aims, the research project was organized in three different
approaches presented in the four chapters of this thesis.
Concerning the quantification of the land use/land cover and identification of
main drivers behind permanent meadows loss, the results show a strong
decrease in meadows (-18.5%) in a context of agricultural land decrease and
human settlements increase. This was the land cover type with highest loss and
conversion rate during the study period. Meadows were converted to human
settlements (urban, industrial and roads), other agriculture uses (cultivation,
orchard, vineyard), bushland and uncultivated land. Meadows loss occurred
mainly in soils with good land capability, low slope, exposed to south and in
proximity of roads, urban settlements and bushland. Densities of urban,
industrial and bushland and land capability were the only significant drivers for
meadows loss, while distance to meadow edge, meadows density, distance to
roads and soil degradation were the only significant drivers for meadows
preservation.
Concerning the characterization of the relationship between biodiversity in the
meadows and the spatial-environmental conditions in the landscape, the results
evidenced that species richness and Shannon indices were best explained by
regressive models including changes occurred in spatial environmental
heterogeneity from 1980 to 2000. Species richness was negatively related to
strong decrease in meadows habitat area and recent urban area, while Shannon
index was positively related to the increase in landscape diversity. In contrast,
species evenness was better explained by regressive model including recent
spatial environmental heterogeneity and positively related to increase ineastness in the study area, and negatively affected both by the area of woody
and soil pH (KCl).
Concerning the evaluation of the use of satellite remotely sensing data for land
cover mapping and change detection in landscape, the results show that the
hybrid approach for land cover classification based of Landsat imagery was
highly accurate. Image differencing is the technique which best detect changes
in landscape as well as in urban, meadow and bush land. The accuracy of
change detection was moderate.
This thesis concludes that the conflict by land in locations densely occupied by
other land cover types with good land capability is the major threat to
meadows and avoidance of fragmentation may be a good strategy for its
preservation. The meadows habitat needs a well-designed landscape and
farming planning, which should account the economic value of the ecosystem
services provided by this habitat. In addition, to conserve plant diversity in
meadows it is necessary to avoid loss of meadows habitat, maintain landscape
diversity and execute a sustainable meadow management.
Remotely sensed imagery can be a reliable source of information for alps,
although particular attention should be made to the image pre-processing and
classification, as well as, to minimize topography effects in spectral
information.
22
Alimonti, Luca. "Développement d'une méthode hybride éléments finis-matrice de transfert pour la prédiction de la réponse vibroacoustique de structures avec traitements acoustiques." Thèse, Université de Sherbrooke, 2014. http://hdl.handle.net/11143/5988.
Full textAbstract:
Résumé : Les véhicules aériens et terrestres sont constitués de systèmes bâtis complexes. La structure principale est généralement composée de panneaux légers renforcés par des éléments rigides. Cette solution de conception est répandue parce qu’elle allie la force et un faible poids. Cependant, on sait qu’elle offre des résultats vibroacoustiques médiocres, c’est à dire que l’effet des perturbations externes qui touchent le système peut générer un niveau de bruit excessif à l’intérieur de la cabine des passagers. C’est une préoccupation majeure chez les fabricants, parce que ce niveau de bruit nuit sensiblement au confort ressenti par les clients et peut causer de la fatigue chez les conducteurs et les pilotes. Pour cette raison, les composants passifs constitués de matériaux dissipatifs assemblés en mode multicouche sont généralement intégrés à la structure. Ces assemblées bordées intègrent surtout des matériaux poroélastiques, qui sont plutôt répandus, grâce à l’agencement intéressant de bonnes propriétés d’isolation sonore et de faible poids.
L’intégration en amont des traitements de contrôle du bruit au processus de conception
est la clé de succès d’un produit. Pour ce faire, des outils pratiques numériques en mesure de capter le comportement dynamique des systèmes vibroacoustiques impliquant les structures, les cavités et les matériaux d’insonorisation sont requis. D’une part, la modélisation de ces systèmes couplés en utilisant des procédés à base d’éléments finis peut être, bien que précis, irréalisable pour des applications pratiques. D’autre part, les approches analytiques telles que la méthode de matrice de transfert sont souvent préférées grâce à leur facilité d’utilisation, même si elles manquent de précision en raison des hypothèses rigoureuses inhérentes au cadre analytique. Dans ce contexte, les procédures de structuration hybrides sont récemment devenues très populaires. En effet, les différentes techniques de modélisation sont généralement recherchées pour décrire les systèmes vibroacoustiques complexes arbitraires sur la plus large gamme de fréquences possible.
L’objectif du projet proposé est de mettre au point un cadre hybride offrant une mé-
thodologie simple pour tenir compte des traitements de contrôle du bruit dans l’analyse
vibroacoustique par éléments finis. A savoir, le modèle de calcul qui en découle conserve la souplesse et la précision de la méthode des éléments finis en bénéficiant de la simplicité et de l’efficacité de la méthode de matrice de transfert pour obtenir une réduction de la charge de calcul pour la modélisation de composants acoustiques passifs. La performance de la méthode pour prédire la réponse vibroacoustique de structures planes homogènes avec des traitements acoustiques attachées est évaluée. Les résultats démontrent que la méthode hybride proposée est très prometteuse, parce qu’elle permet une réduction de l’effort de calcul tout en conservant suffisamment de précision par rapport à l’analyse complète par éléments finis. En outre, la méthode de matrice de transfert proposée de modélisation des traitements de contrôle des bruits est générale, comme on peut l’appliquer dans d’autres cadres outre l’application de l’élément fini considéré dans ce travail. // Abstract : Aerial and terrestrial vehicles consist of complex built-up systems. The main structure is typically made of light panels strengthened by stiffer components. Such design solution is widely used as it combines strength and low weight. However, it is known to give poor vibroacoustic performances, i.e. the effect of external disturbances acting on the system may generate an excessive noise level inside the passengers cabin. This is a main concern for the manufacturers, as it significantly affects the comfort experienced by the costumers and may fatigue drivers and pilots. For this reason, passive components consisting of dissipative materials assembled in a multilayer fashion are typically integrated within the structure. These lined assemblies mainly involve poroelastic materials, which are commonly used thanks to the appealing combination of good noise insulation properties and low weight.
The early integration of noise control treatments in the design process is the key to a successful product. For this purpose, practical numerical tools able to capture the dynamic behavior of vibroacoustic systems involving structures, cavities and noise proofing materials are demanded. On the one hand, modeling such coupled systems using finite element based methods can be, albeit accurate, time consuming for practical applications. On the other hand, analytical approaches such as the transfer matrix method are often preferred thanks to their ease of use, although they suffer from a lack of accuracy due to the stringent assumptions inherent within the analytical framework. In this context, hybrid substructuring procedures have recently become quite popular. Indeed, different modeling techniques are typically sought to describe arbitrarily complex vibroacoustic systems over the widest possible frequency range.
The aim of this thesis is to devise a hybrid framework providing a simple methodology to
account for noise control treatments in vibroacoustic finite element analysis. Namely, the
resulting computational model retains the flexibility and accuracy of the finite element
method while taking advantage from the simplicity and efficiency of the transfer matrix
method to obtain a reduction of the computational burden in the modeling of passive
acoustic components. The performance of the method in predicting the vibroacoustic
response of flat structures with attached homogeneous acoustic treatments is assessed.
The results prove that the proposed hybrid methodology is very promising, as it allows for a reduction of the computational effort while preserving enough accuracy with respect to full finite element analysis. Furthermore, the proposed transfer matrix based methodology for noise control treatments modeling is general, as it can be used in alternative frameworks besides the finite element application considered in this work.
23
Mikoláš, Jiří. "Zkoumání vlivu velikosti aditiv záporné aktivní hmoty na životnost olověného akumulátoru." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218566.
Full textAbstract:
The task of research work is to study new mechanisms and to minimize disturbance of lead batteries for hybrid electric vehicles. Those arising under the PSoC (Partial State of Charge) and is linked to irreversible sulphation mainly negative electrodes. As one solution to prevent sulphation of the negative electrode appears to be the active ingredients in a negative matter. In the investigated electrodes is verified the influence of carbon, titanium dioxide and silica on the grain size of the order of nanometers.
24
Vystrčil, Marek. "Zkoumání příčin předčasné ztráty kapacity v olověných akumulátorech pro hybridní elektrická vozidla." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218569.
Full textAbstract:
This thesis describes the results of two successive experiments. The first was focused on the influence of impurities in the active mass of negative electrode in PSoC (Partial State of Charge) mode, which simulates the conditions occurring in HEV (hybrid electric vehicle). In the second experiment, cells with the same additives were exposed to optimum downforce 4N/cm2, by which we wanted to prove the influence of pressure on life of VRLA (Valve Regulated Lead Acid) cells working in operating HEV conditions.
25
Svoboda, Marek. "Vliv přítlaku v olověných akumulátorech pro hybridní elektrická vozidla." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-218939.
Full textAbstract:
Lead-acid batteries of hybrid electric vehicles (HEV) are functioning in PSoC regime (Partial State of Charge). In PSoC regime new fail mechanisms occur. These mechanisms usually lead to nonreversible sulphation of negative electrodes. Main aim of this research is to avoid negative electrode sulphation and to improve lifetime of lead-acid accumulators used in HEV.
26
Azgin, Aytac. "Service quality assurance for the IPTV networks." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/48961.
Full textAbstract:
The objective of the proposed research is to design and evaluate end-to-end solutions to support the Quality of Experience (QoE) for the Internet Protocol Television (IPTV) service. IPTV is a system that integrates voice, video, and data delivery into a single Internet Protocol (IP) framework to enable interactive broadcasting services at the subscribers. It promises significant advantages for both service providers and subscribers. For instance, unlike conventional broadcasting systems, IPTV broadcasts will not be restricted by the limited number of channels in the broadcast/radio spectrum. Furthermore, IPTV will provide its subscribers with the opportunity to access and interact with a wide variety of high-quality on-demand video content over the Internet. However, these advantages come at the expense of stricter quality of service (QoS) requirements than traditional Internet applications. Since IPTV is considered as a real-time broadcast service over the Internet, the success of the IPTV service depends on the QoE perceived by the end-users. The characteristics of the video traffic as well as the high-quality requirements of the IPTV broadcast impose strict requirements on transmission delay. IPTV framework has to provide mechanisms to satisfy the stringent delay, jitter, and packet loss requirements of the IPTV service over lossy transmission channels with varying characteristics. The proposed research focuses on error recovery and channel change latency problems in IPTV networks. Our specific aim is to develop a content delivery framework that integrates content features, IPTV application requirements, and network characteristics in such a way that the network resource utilization can be optimized for the given constraints on the user perceived service quality. To achieve the desired QoE levels, the proposed research focuses on the design of resource optimal server-based and peer-assisted delivery techniques. First, by analyzing the tradeoffs on the use of proactive and reactive repair techniques, a solution that optimizes the error recovery overhead is proposed. Further analysis on the proposed solution is performed by also focusing on the use of multicast error recovery techniques. By investigating the tradeoffs on the use of network-assisted and client-based channel change solutions, distributed content delivery frameworks are proposed to optimize the error recovery performance. Next, bandwidth and latency tradeoffs associated with the use of concurrent delivery streams to support the IPTV channel change are analyzed, and the results are used to develop a resource-optimal channel change framework that greatly improves the latency performance in the network. For both problems studied in this research, scalability concerns for the IPTV service are addressed by properly integrating peer-based delivery techniques into server-based solutions.
27
Klaner, Pavel. "Vliv aditiv v olověných akumulátorech pro hybridní elektrická vozidla." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219876.
Full textAbstract:
This thesis deals with issues of the issue lead-acid batteries and their application in mode of hybrid electric vehicle. The experiment is focused on the production of electrodes to determine the effect five types of additives in negative active mass in PsoC(Partial State of Charge) mode. This simulates conditions occurring in the mode of hybrid electric vehicles (HEV).
28
Klojda, Viktor. "Vliv skelných vláken v olověných akumulátorech pro hybridní elektrická vozidla." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219872.
Full textAbstract:
Master´s thesis deals with the utilization of lead-acid accumulators in hybrid electric vehicle regime. It describes the side effects known as PCL, generated during PSOC regime and connected with the length of the battery lifespan. One possibility how to eliminate these effects, is the use of additives in active mass of the negative electrode, in the form of glass fibres. The project provides the parametres and reactions of additive, that have lead to the improvement of battery properties. The purpose of this thesis is to verify the positive effect of the aditive on the lifespan of the lead-acid accumulator.
29
Konečný, Zdeněk. "Vliv oxidu titaničitého na vlastnosti olověných akumulátorů pracujících v režimu hybridních vozidel." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219871.
Full textAbstract:
This work deals with lead-acid batteries operating in hybrid electric vehicles mode, i.e. in a partial state of charge. The adverse effects such as premature capacity loss and large internal resistance can markedly affect the life of a lead battery. The experiment described in this work aims to clarify the influence of the titanium dioxide in the active mass of negative electrodes especially in the life of lead acid batteries.
30
Nie, Chunyang. "Etude de nanocristaux unidimensionnels confinés dans des nanotubes de carbone." Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30214/document.
Full textAbstract:
Le remplissage des nanotubes de carbone (NTC) est considéré comme une approche relativement simple permettant de synthétiser des nanocristaux du fait de l'effet de confinement 1D imposé par la cavité centrale des NTC, qui peut être seulement de l'ordre du nanomètre ou moins, notamment dans le cas des NTC monoparoi et en particulier des NTC biparois (DWCNT) sur lesquels nous avons concentré nos efforts. De tels nanocristaux devraient avoir des propriétés physiques (électriques, magnétiques) différentes de celles de leurs équivalents à l'état massif du fait de la modification de la coordinence des atomes ou des ions les composant. Parmi les différentes méthodes existantes pour le remplissage des NTC, (in situ pendant la synthèse, a posteriori à partir de solutions), la méthode faisant intervenir des matériaux fondus est la plus populaire pour le remplissage par des matériaux inorganiques. Elle permet en effet d'atteindre des taux de remplissage raisonnablement élevés et demeure assez simple à mettre en œuvre. Cependant, elle fait preuve d'un certain nombre de limitations (techniques) qui posent problème dans le cas de matériaux à haut point de fusion (typiquement > 1000°C), dont la réactivité avec le carbone à haute température pourrait être gênante (carboréduction des oxydes par exemples), ou encore dont la faible mouillabilité vis-à-vis du carbone à l'état fondu est rédhibitoire (métaux par exemple). Il est possible de palier à cette difficulté en procédant par étapes successives et en remplissant d'abord les NTC avec un précurseur puis d'utiliser la cavité interne des NTC comme des nanoréacteurs afin de procéder dans un second temps à une transformation in situ. Dans ces travaux, nous avons étudié (1) le remplissage de DWCNT avec de l'iode ainsi qu'avec différents iodures métalliques en mettant en œuvre essentiellement la méthode des sels fondus. Nous avons étudié en détails l'influence des paramètres physico-chimiques du matériau de remplissage (réactivité chimique sous la forme en particulier du potentiel rédox du couple iodure métallique / métal, mais aussi viscosité, tension de surface, pression de vapeur saturante en milieu fondu) mais aussi du NTC (texture cylindrique ou "en arrêtes de poisson", diamètre, nombre de parois) sur le taux de remplissage. (2) Nous avons étudié en détail un certain nombre de structures inhabituelles de nanomatériaux confinés dans les DWCNT, en faisant appel à la modélisation structurale et à la simulation d'images de microscopie électronique sur la base de ces modèles pour guider notre analyse. (3) Nous avons enfin étudié différentes réactions in situ dans les DWCNT telles que la sulfuration, la réduction sous hydrogène ou encore la fluoration afin de synthétiser des nanocristaux originaux et de les caractériser en détails à l'aide d'outils tels que par exemple le MET Haute Résolution et la spectroscopie de perte d'énergie des électrons (EELS)Filling carbon nanotubes (CNTs) has been considered as an easy approach to synthesize various nanocrystals since the inserted materials are forced to adopt a nearly one-dimensional morphology arising from their very high aspect ratio, especially in the case of single-walled CNTs (SWCNTs) or double-walled CNTs (DWCNTs). Nanocrystals/nanowires of transition metals, especially those with very narrow diameters, are predicted to exhibit peculiar magnetic property differing from the bulk metals. Filling CNTs provides a possible way for the synthesis of such metal nanocrystals/nanowires. There are several methods for filling CNTs including the in situ method, gas phase method, molten phase method, solution method, etc. Among them, molten phase has been very popular for filling various types of nanotubes due to the possibility to reach high filling rates, simplicity and versatility. However, for materials with high melting point such as metals, it is difficult to insert them into CNTs directly. To solve this problem, we also took advantage of the inner cavity of CNTs which not only templates the growth but also acts as a nanoreactor in order to perform chemical reactions. The insertion of materials with high melting point is typically achieved by first filling CNTs with a precursor, and then transforming the precursor into the desired 1D nanostructure by post-treatments. In this thesis, (i) filling DWCNTs with iodine and various halides via the molten phase method was performed and the influence of the relevant physical and chemical properties of the halides on the filling rate was investigated. The role of the redox potential as a main parameter driving the filling efficiency is pointed out, and explained; (ii) peculiar structures of the nanocrystals confined within DWCNTs were imaged by transmission electron microscopy (TEM) and corresponding modeling of the observed crystal nanostructures and related TEM images were proposed; (iii) different in situ transformations on the iodide-filled DWCNTs were attempted and the chemical composition of the encapsulated 1D nanocrystals before and after post-filling treatments was systematically identified by means of electron energy loss spectroscopy (EELS)
31
Tobolák, Jakub. "Vliv vodivých keramik na životnost olověných akumulátorů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220971.
Full textAbstract:
This thesis is focused on lead-acid batteries used in hybrid electric vehicles. These cells work in specific conditions, particularly under partial charge referred to as PSOC. This fact is responsible for the premature loss of capacity cell lead-acid batteries and their short lifetime. The task of this thesis is to examine the effect of conductive ceramics as possible additives to the negative electrode active materials of lead-acid battery cells operating in a PSOC, in order to prolong their life.
32
Zhao, Zhou. "Heart Segmentation and Evaluation of Fibrosis." Electronic Thesis or Diss., Sorbonne université, 2023. http://www.theses.fr/2023SORUS003.
Full textAbstract:
La fibrillation auriculaire est la maladie du rythme cardiaque la plus courante. En raison d'un manque de compréhension des structures atriales sous-jacentes, les traitements actuels ne sont toujours pas satisfaisants. Récemment, avec la popularité de l'apprentissage profond, de nombreuses méthodes de segmentation basées sur l'apprentissage profond ont été proposées pour analyser les structures auriculaires, en particulier à partir de l'imagerie par résonance magnétique renforcée au gadolinium tardif. Cependant, deux problèmes subsistent : 1) les résultats de la segmentation incluent le fond de type atrial ; 2) les limites sont très difficiles à segmenter. La plupart des approches de segmentation conçoivent un réseau spécifique qui se concentre principalement sur les régions, au détriment des frontières. Par conséquent, dans cette thèse, nous proposons deux méthodes différentes pour segmenter le cœur, une méthode en deux étapes et une méthode entraînable de bout en bout. Ensuite, pour évaluer le degré de fibrose, nous avons également proposé deux méthodes, l'une consiste à combiner l'apprentissage profond avec la morphologie, et l'autre à utiliser directement l'apprentissage profond. Enfin, l'efficacité de l'approche proposée est vérifiée sur certains jeux de données publicsAtrial fibrillation is the most common heart rhythm disease. Due to a lack of understanding in the matter of underlying atrial structures, current treatments are still not satisfying. Recently, with the popularity of deep learning, many segmentation methods based on deep learning have been proposed to analyze atrial structures, especially from late gadolinium-enhanced magnetic resonance imaging. However, two problems still occur: 1) segmentation results include the atrial-like background; 2) boundaries are very hard to segment. Most segmentation approaches design a specific network that mainly focuses on the regions, to the detriment of the boundaries. Therefore, in this dissertation, we propose two different methods to segment the heart, one two-stage and one end-to-end trainable method. And then, for evaluating the fibrosis degree, we also proposed two methods, one is to combine deep learning with morphology, and the other is to use deep learning directly. Finally, the efficiency of the proposed approach is verified on some public datasets
33
Bellanger, Adrien. "Ordonnancement sur les machines à traitement par batches et contraintes de compatibilité." Phd thesis, Institut National Polytechnique de Lorraine - INPL, 2009. http://tel.archives-ouvertes.fr/tel-00606383.
Full textAbstract:
Dans cette thèse, nous avons traité les problèmes d'ordonnancement d'ateliers de type flow- shop hybride à deux étages avec machines à traitement par batches sur le second étage et compatibilité entre les tâches. Les durées opératoires des tâches sont données par des intervalles, et les tâches sont dites compatibles si elles partagent une même durée d'exécution. Pour le problème de minimisation de la date de fin d'ordonnancement de ce type d'atelier, nous avons développé 6 heuristiques à performances garanties. D'après les expériences réalisées, ces heuristiques sont efficaces sur de grandes instances. Pour les petites instances, nous avons présenté deux méthodes exactes de type procédures par séparation évaluation qui permettent de résoudre des instances de 20 tâches. Nous avons également développé un schéma d'approximation polynomial (PTAS) utilisable lorsque les durées d'exécution sur le premier étage sont identiques. En complément de ces travaux, nous avons également étudié d'autres problèmes de minimisation de critères réguliers sur une machine à traitement par batches. Nous avons développé des algorithmes de programmation dynamiques pseudo-polynomiaux pour les problèmes de minimisation de la somme des dates de fin d'exécution et pour les problèmes avec dates de fin souhaitées. Afin de compléter ces résultats de complexité, nous avons montré la NP-complétude des problèmes avec dates de fin souhaitées.
34
Esgin, Eren. "A Hybrid Methodology In Process Modeling:." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12610461/index.pdf.
Full textAbstract:
The managing of complex business processes, which are changed due to globalization, calls for the development of powerful information systems that offer generic process modeling and
process execution capabilities.
Even though contemporary information systems are more and more utilized in enterprises, their actual impact in automatizing complex business process is still limited by the difficulties
encountered in design phase. Actually this design phase is time consuming, often subjective and incomplete.
In the scope of this study, a reverse approach is followed. Instead of starting with process design, the method of discovering interesting patterns from the navigation traces is taken as basis and a new data analysis methodology named &ldquoFrom-to Chart Based Process Discovery&rdquo
is proposed. In this hybrid methodology &ldquo
from-to chart&rdquo
, which is fundamentally dedicated to material handling issues on production floor, is used as the front-end to monitor the transitions among activities of a realistic event log and convert these raw relations into optimum activity sequence. Then a revised version of process mining, which is the back-end of this methodology, upgrades optimum activity sequence into process model.
35
Masoudi, Pedram. "Application of hybrid uncertainty-clustering approach in pre-processing well-logs." Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1S023/document.
Full textAbstract:
La thèse est principalement centrée sur l'étude de la résolution verticale des diagraphies. On outre, l'arithmétique floue est appliquée aux modèles expérimentaux pétrophysiques en vue de transmettre l'incertitude des données d'entrée aux données de sortie, ici la saturation irréductible en eau et la perméabilité. Les diagraphies sont des signaux digitaux dont les données sont des mesures volumétriques. Le mécanisme d'enregistrement de ces données est modélisé par des fonctions d'appartenance floues. On a montré que la Résolution Verticale de la Fonction d'Appartenance (VRmf) est supérieur d'espacement. Dans l'étape suivante, la fréquence de Nyquist est revue en fonction du mécanisme volumétrique de diagraphie ; de ce fait, la fréquence volumétrique de Nyquist est proposée afin d'analyser la précision des diagraphies. Basé sur le modèle de résolution verticale développée, un simulateur géométrique est conçu pour générer les registres synthétiques d'une seule couche mince. Le simulateur nous permet d'analyser la sensibilité des diagraphies en présence d'une couche mince. Les relations de régression entre les registres idéaux (données d'entrée de ce simulateur) et les registres synthétiques (données de sortie de ce simulateur) sont utilisées comme relations de déconvolution en vue d'enlever l'effet des épaules de couche d'une couche mince sur les diagraphies GR, RHOB et NPHI. Les relations de déconvolution ont bien été appliquées aux diagraphies pour caractériser les couches minces. Par exemple, pour caractériser une couche mince poreuse, on a eu recours aux données de carottage qui étaient disponibles pour la vérification : NPHI mesuré (3.8%) a été remplacé (corrigé) par 11.7%. NPHI corrigé semble être plus précis que NPHI mesuré, car la diagraphie a une valeur plus grande que la porosité de carottage (8.4%). Il convient de rappeler que la porosité totale (NPHI) ne doit pas être inférieure à la porosité effective (carottage). En plus, l'épaisseur de la couche mince a été estimée à 13±7.5 cm, compatible avec l'épaisseur de la couche mince dans la boite de carottage (<25 cm). Normalement, l'épaisseur in situ est inférieure à l'épaisseur de la boite de carottage, parce que les carottes obtenues ne sont plus soumises à la pression lithostatique, et s'érodent à la surface du sol. La DST est appliquée aux diagraphies, et l'intervalle d'incertitude de DST est construit. Tandis que la VRmf des diagraphies GR, RHOB, NPHI et DT est ~60 cm, la VRmf de l'intervalle d'incertitude est ~15 cm. Or, on a perdu l'incertitude de la valeur de diagraphie, alors que la VRmf est devenue plus précise. Les diagraphies ont été ensuite corrigées entre l'intervalle d'incertitude de DST avec quatre simulateurs. Les hautes fréquences sont amplifiées dans les diagraphies corrigées, et l'effet des épaules de couche est réduit. La méthode proposée est vérifiée dans les cas synthétiques, la boite de carottage et la porosité de carotte. L'analyse de partitionnement est appliquée aux diagraphies NPHI, RHOB et DT en vue de trouver l'intervalle d'incertitude, basé sur les grappes. Puis, le NPHI est calibré par la porosité de carottes dans chaque grappe. Le √MSE de NPHI calibré est plus bas par rapport aux cinq modèles conventionnels d'estimation de la porosité (au minimum 33% d'amélioration du √MSE). Le √MSE de généralisation de la méthode proposée entre les puits voisins est augmenté de 42%. L'intervalle d'incertitude de la porosité est exprimé par les nombres flous. L'arithmétique floue est ensuite appliquée dans le but de calculer les nombres flous de la saturation irréductible en eau et de la perméabilité. Le nombre flou de la saturation irréductible en eau apporte de meilleurs résultats en termes de moindre sous-estimation par rapport à l'estimation nette. Il est constaté que lorsque les intervalles de grappes de porosité ne sont pas compatibles avec la porosité de carotte, les nombres flous de la perméabilité ne sont pas valablesIn the subsurface geology, characterization of geological beds by well-logs is an uncertain task. The thesis mainly concerns studying vertical resolution of well-logs (question 1). In the second stage, fuzzy arithmetic is applied to experimental petrophysical relations to project the uncertainty range of the inputs to the outputs, here irreducible water saturation and permeability (question 2). Regarding the first question, the logging mechanism is modelled by fuzzy membership functions. Vertical resolution of membership function (VRmf) is larger than spacing and sampling rate. Due to volumetric mechanism of logging, volumetric Nyquist frequency is proposed. Developing a geometric simulator for generating synthetic-logs of a single thin-bed enabled us analysing sensitivity of the well-logs to the presence of a thin-bed. Regression-based relations between ideal-logs (simulator inputs) and synthetic-logs (simulator outputs) are used as deconvolution relations for removing shoulder-bed effect of thin-beds from GR, RHOB and NPHI well-logs. NPHI deconvolution relation is applied to a real case where the core porosity of a thin-bed is 8.4%. The NPHI well-log is 3.8%, and the deconvolved NPHI is 11.7%. Since it is not reasonable that the core porosity (effective porosity) be higher than the NPHI (total porosity), the deconvolved NPHI is more accurate than the NPHI well-log. It reveals that the shoulder-bed effect is reduced in this case. The thickness of the same thin-bed was also estimated to be 13±7.5 cm, which is compatible with the thickness of the thin-bed in the core box (<25 cm). Usually, in situ thickness is less than the thickness of the core boxes, since at the earth surface, there is no overburden pressure, also the cores are weathered. Dempster-Shafer Theory (DST) was used to create well-log uncertainty range. While the VRmf of the well-logs is more than 60 cm, the VRmf of the belief and plausibility functions (boundaries of the uncertainty range) would be about 15 cm. So, the VRmf is improved, while the certainty of the well-log value is lost. In comparison with geometric method, DST-based algorithm resulted in a smaller uncertainty range of GR, RHOB and NPHI logs by 100%, 71% and 66%, respectively. In the next step, cluster analysis is applied to NPHI, RHOB and DT for the purpose of providing cluster-based uncertainty range. Then, NPHI is calibrated by core porosity value in each cluster, showing low √MSE compared to the five conventional porosity estimation models (at least 33% of improvement in √MSE). Then, fuzzy arithmetic is applied to calculate fuzzy numbers of irreducible water saturation and permeability. Fuzzy number of irreducible water saturation provides better (less overestimation) results than the crisp estimation. It is found that when the cluster interval of porosity is not compatible with the core porosity, the permeability fuzzy numbers are not valid, e.g. in well#4. Finally, in the possibilistic approach (the fuzzy theory), by calibrating α-cut, the right uncertainty interval could be achieved, concerning the scale of the study
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Brown, Sarah(Sarah Dalton). "Hybrid-industrial zoning : a case study in Downtown Los Angeles." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/122271.
Full textAbstract:
Thesis: M.C.P., Massachusetts Institute of Technology, Department of Urban Studies and Planning, 2019Thesis: S.M. in Real Estate Development, Massachusetts Institute of Technology, Program in Real Estate Development in conjunction with the Center for Real Estate, 2019
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 89-93).
Historically, land use planning has treated industrial land uses either antagonistically or ambivalently. Traditional zoning approaches have restricted, regulated, spatially isolated, and pushed industrial land to the periphery of cities, resulting in a significant loss of urban industrial land across American cities. But as the United States experiences a manufacturing renaissance and cities begin to recognize the value of centrally located industrial land in its contribution to the regional economy, planners are grappling with the issue of how best to secure these viable but vulnerable sites of employment and production. Advanced technologies that are changing the nature of manufacturing and logistics present an exciting opportunity and potential solution: the industrial mixed-use zone. This thesis explores the emerging land use tool of industrial-mixed use zoning, using Los Angeles as a case study.
The intent of the industrial mixed-use zone, which permits non-industrial uses, to varying degrees of intensities, in otherwise industrial districts, is to protect central locations for industrial operations when market forces might otherwise price them out. On the one hand, the zone can impede industrial business displacement through offering protection to compatible lighter industrial uses in transitioning neighborhoods. In doing so, it aims to create a live/work urban district in which several planning agendas are met and balanced, providing for industrial employment alongside affordable housing and public realm improvements. On the other hand, without strict use definitions, mix requirements or consistent regulation, the industrial mixed-use zone risks both accelerating the land use conversion process, operating as residential and commercial upzoning, and gentrifying industrial districts toward more artisanal and boutique industrial operations.
In 2019, the Los Angeles Department of City Planning will rezone industrial land in Downtown Los Angeles under a new zoning classification: hybrid-industrial. Through an exploration of Los Angeles' industrial land use policies, a process tracing of the evolution of hybrid-industrial zoning, and a dissection of the zoning ordinance's text, this thesis demonstrates the trade-offs associated with a mixed-use district and the potential challenges and pitfalls of implementation.
by Sarah Brown.
M.C.P.
S.M. in Real Estate Development
M.C.P. Massachusetts Institute of Technology, Department of Urban Studies and Planning
S.M.inRealEstateDevelopment Massachusetts Institute of Technology, Program in Real Estate Development in conjunction with the Center for Real Estate
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Baudoin, Romain. "Analyse du bruit lors de la génération de somme de fréquences dans les cristaux de niobate de lithium périodiquement polarisés (PPLN) et applications en régime de comptage de photons." Thesis, Limoges, 2014. http://www.theses.fr/2014LIMO0068/document.
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Le processus de somme de fréquences optiques est utilisé dans certaines applications pour convertir des signaux de longueurs d’onde infrarouges vers le domaine de longueurs d’onde visibles. Cela permet de bénéficier de technologies plus performantes notamment en terme de détection et de propagation. Les travaux menés dans cette thèse s’intéressent à l’étude de phénomènes optiques parasites générés par ce processus non linéaire dans des cristaux de niobate de lithium périodiquement polarisés (PPLN) pour des applications de conversion de fréquences en régime de comptage de photons. La première partie de ce manuscrit montre l’intérêt du processus de somme de fréquences optiques dans le contexte technologique de la détection infrarouge en régime de comptage de photons, via le concept de détection hybride. Les éléments théoriques et l’état de l’art associés à la détection hybride seront également présentés dans cette première partie. La deuxième partie traite d’une étude comparative entre différents cristaux de PPLN pour la détection hybride à 1550 nm. Pour cela, une analyse expérimentale détaillée des processus parasites est effectuée. Les résultats de cette étude sont utilisés pour des applications en astronomie et en microscopie. Enfin, la troisième partie traite d’une application de la somme de fréquences en interférométrie stellaire. Les résultats de caractérisation des cristaux de PPLN sont mis à contribution dans l’optimisation d’un instrument pour l’astronomie appelé interféromètre à somme de fréquences. Les résultats d’observation sur le site astronomique du Mont Wilson ainsi que les perspectives de cette instrument y sont présentésThe sum frequency generation process is used in differents applications to convert signals from infrared wavelengths to the field of visible wavelength. This allows to benefit of more efficient technologies in terms of detection and propagation. This thesis describes the study of noise phenomena generated by this process in crystals of periodically poled lithium niobate (PPLN) for frequency up-conversion applications in photon counting regime. The first part of the manuscript shows the advantage of sum frequency generation process in the technological environment of the infrared detection on single photon counting regime, using the concept of hybrid detection. The theoretical elements and the state of the art associated with hybrid detection will also be presented in this first part. The second part deals with a comparative study between different PPLN for hybrid detection at 1550 nm. A detailed experimental analysis of the noise process is performed. The results of this study are used for applications in astronomy and microscopy. The third part deals with an application of the sum frequency in stellar interferometry. The results of PPLN’s characterization are involved in optimizing an instrument for astronomy called sum frequency interferometer. The results of observation on the astronomical site of Mount Wilson and the prospects of this instrument are presented
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Oliveira, Sueyde Fernandes de. "Use efficiency of controlled release fertilizer on the growth of croton and petunia and N loss by leaching." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-10052016-134408/.
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The market of flowers and ornamentals such as croton (Codiaeum variegatum) and petunia (Petunia×hybrida Vilm.-Andr) have been created new technologies to constantly development, as one of the most promising segments of horticulture. Fertilization providing adequate nutrition and less leaching to the environment is the objective of numerous studies around the world. Therefore, two studies were conducted to evaluate the use of controlled release fertilizer (CRF) on the growth of two ornamental species, and N loss by leaching. The first experiment aim to evaluate sources and rates of CRF and water soluble fertilizer (WSF) on croton growth and nitrogen concentration on drained solution. Results showed that treatments with WSF and low rates of CRF provided higher plants growth, and the amount of N leached was higher for WSF treatments. The second experiment objective to compare plant performance and cost for strategies that potentially provide adequate nutrition during both the production and consumer phases for container-grown Petunia plants. In addition, two experiments were conducted to evaluate nutrient release in sand containers inside of the greenhouse and under controlled temperature conditions without plants. Results showed that during production phase all fertilizer treatments produced high quality plants, and during consumer phase, plants grown with WSF only during the production phase were nutrient-deficient, while plants receiving CRFs were still growing vigorously, especially in a high rate. The release rates of all CRF products were temperature-dependent. In conclusion CRF provided plant growth at the same rate that WSF, with less N leaching and extra cost less than U$0.065 per plant with CRF during production.O mercado de flores e plantas ornamentais tais como cróton (Codiaeum variegatum) e petúnia (Petunia×hybrida Vilm.-Andr) apresenta-se em constante desenvolvimento tecnológico, caracterizando-se como um dos mais promissores segmentos da horticultura. A adubação, visando o aumento da eficiência do fertilizante e redução de perdas, são temas de estudos em todo o mundo. Assim, foram realizados dois experimentos para avaliar o uso de fertilizantes de liberação controlada (FLC) no crescimento de duas espécies de plantas ornamentais e a perda de nitrogênio por lixiviação. O primeiro experimento teve como objetivo avaliar fontes e doses de FLC e solução nutritiva no crescimento de cróton e a concentração de nitrogênio (N) na solução drenada dos vasos. Os resultados revelaram que a solução nutritiva e as menores concentrações de FLC proporcionaram o maior crescimento das plantas, e as taxas de N perdidas por lixiviação foram superiores para o tratamento com solução. O segundo experimento objetivou comparar estratégias de adubação que proporcionem nutrição adequada durante a fase de produção e do consumidor com menor custo, as quais incluíam FLC e solução nutritiva. Simultaneamente, foram realizados dois experimentos para avaliar a liberação de nitrogênio pelos fertilizantes, sem as plantas, nas condições de cultivo das plantas (estufa) e em câmaras de crescimento sob três temperaturas de incubação. Os resultados mostraram que durante a fase de produção todos os tratamentos resultaram em plantas nos padrões comerciais, e no período que simulou a fase do consumidor as plantas que receberam apenas solução nutritiva durante a fase de produção apresentaram deficiência nutricional, enquanto com os FLC as plantas cresceram vigorosamente, principalmente para os tratamentos com as maiores doses. Os fertilizantes avaliados apresentaram diferença quanto à temperatura na liberação dos nutrientes, sendo maior a taxa de liberação quanto maior a temperatura. De acordo com os resultados o FLC proporcionou o crescimento das plantas na mesma proporção que a solução nutritiva, com uma redução na concentração de N por lixiviação e acréscimo inferior a U$0.065 no custo por planta quando utilizado FLC durante a produção.
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Barthes, Julien. "Adressage et contrôle de nanosources optiques par plasmonique intégrée ou fibrée." Thesis, Dijon, 2015. http://www.theses.fr/2015DIJOS011/document.
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Les plasmons polaritons de surface, modes supportés par des nanostructures métalliques permettent de confiner la lumière à des échelles sub-longueurs d’onde. En s’affranchissant de la limite de diffraction, ces modes constituent des pistes intéressantes pour l’adressage et le contrôle de nanosources optiques (molécules, boites quantiques...). Par exemple, un nanofil métallique constitue un guide plasmonique unidimensionnel qui permet d’exciter une nanosource ou encore de coupler deux émetteurs avec des applications possibles pour la réalisation de composants nano-optiques intégrés. En revanche, la perte d’énergie dans le métal diminue la portée de ces dispositifs. Une stratégie consiste donc à travailler sur une configuration hybride : plasmonique et fibre optique, pour coupler efficacement l’émission de la nanosource à un mode de fibre. Ceci ouvre la voie à la réalisation d’une nanosource fibrée de manipulation aisée pouvant être utilisée comme source de photon unique pour la cryptographie quantique ou plus simplement comme une sonde de champ proche optique haute résolution.Après une étude des principaux canaux de relaxation d’une molécule fluorescente à proximité d’un guide plasmonique, nous discutons de l’optimisation du couplage entre l’émetteur et le guide plasmonique en jouant sur sa forme et la longueur d’onde d’émission. Ensuite, nous nous intéressons au comportement d’une structure hybride composée d’une fibre optique étirée et métallisée. Enfin, nous montrons que l’optimisation du transfert d’énergie d’une molécule fluorescente en présence de cette structure permet de collecter plus de 50% de l’énergie lumineuse d’un nano-émetteur posé sur un substrat vers une fibre optique par le truchement d’un plasmonSurface plasmon polariton (SPP) can confine light on subwavelength dimensions. Since they are not diffraction limited, they are of great interest for addressing and controlling optical nanosources. For example, a metal nanowire defines 1D plasmonic waveguide with a great potential for either addressing or coupling quantum emitters. Therefore, SPP opens great opportunities for integrated optical applications. However, SPP suffer from ohmic losses that jeopardize the applications of plasmonic components. In this context, we study the possibilities provided by an hybrid plasmonic-photonicstructure to couple efficiently an emitter to a fiber mode. Such a structure paves the way for fibered single photon nanosource or high resolution optical probe. In this thesis manuscript, we first study the coupling rate between a fluorescent molecule and a metallic nanowire thanks to Green’s dyad formalism. This leads us to distinguish the different relaxation channels and the enhancement of the energy transferred into the plasmonic guided mode by optimizing the shape of the guide (crystalline nano-wire,slow modes). Then, we investigate the energy propagation in a metal coated taperedoptical fiber. Finally, we achieve an optimal configuration for which more than 50% of the energy emitted by a quantum emitter laid on a substrat is transferred into an optical fiber
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Tkachenko, Iuliia. "Contribution à la compréhension et à la modélisation des phénomènes physiques se produisant lors d'un assemblage par procédé hybride laser-arc." Thesis, Dijon, 2015. http://www.theses.fr/2015DIJOS012.
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Ces travaux présentent une recherche sur la physique du soudage hybride. La revue littéraire décrit les principaux processus physiques se produisant au cours de la combinaison Laser-arc, les principales réalisations et les problèmes rencontrés lors de l'analyse de ces processus. Les processus ont été étudiés pendant l'assemblage de matériaux de fortes épaisseurs. Deux configurations ont été utilisées. La première est le soudage d’un acier Superduplex en un seul passage, par Laser et arc distanciés. La seconde configuration est le soudage multipasse de l'acier 18MND5, où le faisceau Laser défocalisé intercepte le plasma d'arc électrique. Avec l'aide de la planification d'expérience, l'imagerie vidéo rapide, l'enregistrement des signaux électriques, la détermination de la température et des distorsions de l’assemblage ont permis d’expliquer le rôle de chaque source thermique et l'influence de leur combinaison sur la création du bain fondu, l'identification du mode de transfert métallique et la répartition de la chaleur dans la plaque soudée. Les relations entre les signaux électriques et la géométrie de l'arc, les dimensions du bain et la distribution de chaleur sont analysées à différentes échelles de temps. L'analyse thermique présentée montre que l'hypothèse de stationnarité, qui est largement utilisé par les simulateurs, est vraie seulement sur une courte période et pour une longueur donnée de soudure. L’analyse macrographique montre, quant à elle, l'effet de la variation des paramètres d'entrée sur la structure et la géométrie de la soudureAn investigation on hybrid welding physics is presented in the current work. A literature review describes main physical processes occurring during Laser-arc combination and shows main achievements and problematics met during process analysis. Physical processes were studied during joining of very thick materials. Two configurations were used. The first configuration is welding of Superduplex steel in one pass by Laser and arc that are far apart. The second configuration is multipass welding of 18MND5 steel, where defocused Laser beam intercepts arc plasma. With a help of experiment’s design, fast video imaging, electric signals recording, determination of temperature and workpiece distortion, were explained the role of each thermal source and influence of their combination on arc behaviour, molten pool creation, metallic drop transfer evaluation and heat distribution into welded plates. The relationships between electric signals and arc geometry, bath dimensions and heat distribution have been analyzed at various time scales. Thermal analysis, presented in this work, shows that hypothesis of stationarity, which is commonly used in numerical modelling, is true only during a short welding period and for a given weld length. Macrographic analysis shows effect of input parameters variation on weld’s structure and geometry
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Bargshady, Nader. "Precise Tracking of Things via Hybrid 3-D Fingerprint Database and Kernel Method Particle Filter." Digital WPI, 2017. https://digitalcommons.wpi.edu/etd-dissertations/361.
Full textAbstract:
"Precise Tracking of Things (PToT) using RF signals has posed a serious challenge in an indoor environment. The precision localization information is an enabler for better coordinated-tasks and is essential for a successful launch of many emerging applications. PToT relies on two principal components, a novel navigation (tracking) algorithm, and a hybrid 3D fingerprint database. In this dissertation, we begin by using the two widely known ranging techniques, Time Of Arrival (TOA) associated with Ultra-wideband (UWB) and Received Signal Strength (RSS) with WiFi signals. First, we use the theoretical models derived from empirical measurement of TOA and RSS to analyze the performance of hybrid (WiFi & UWB) cooperative localization accuracy in a multi-robot operation in a typical office environment. To measure the performance of this hybrid localization, we derive a mathematical formulation for the Crame ́r-Rao-Lower- Bound (CRLB). The hybrid method shows more accuracy over WiFi-only approach. In achieving more precision, we extend our work. Second, we introduce a novel approach, a Kernel Method Particle Filter (KMPF) for tracking and predicting the position by accessing the information created by hybrid 3D fingerprint database. We derive the mathematical and statistical framework for the Particle Filter based on the statistical assumptions about the behavior of channel models. We also describe the formation of one of the necessary PToT component, a 3D fingerprint database. We compare the performance of the KMPF against the CRLB using WiFi signal channel models."
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Gregorio, Jean-Loup. "Contribution à la définition d'un jumeau numérique pour la maîtrise de la qualité géométrique des structures aéronautiques lors de leurs processus d'assemblage." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASN008.
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Les opérations d'assemblage de structures aéronautiques font aujourd'hui appel à une planification particulière se basant sur la maquette numérique des produits considérés. Pour permettre une bonne réalisation de ces opérations, la géométrie du produit physique doit rester aussi fidèle que possible à la géométrie de référence contenue dans la maquette numérique. Du fait de la complexité des produits considérés, des écarts géométriques non-anticipés peuvent cependant apparaitre et occasionner un allongement des délais et une augmentation des coûts d’assemblage.L’intégration croissante de systèmes de traitement de l’information ouvre des perspectives nouvelles quant à la façon d’organiser les systèmes de production. Ces perspectives incluent notamment la possibilité d’optimiser les opérations de fabrication et d’assemblage en temps réel à travers l’utilisation de jumeaux numériques des produits manufacturés. Nous proposons dans ces travaux la mise en place d’un jumeau numérique géométrique, capable de refléter la géométrie du produit physique en cours d’assemblage et d’optimiser la géométrie de certains composants restant à assembler.Dans cette optique, la maquette numérique initiale est actualisée afin d’obtenir une représentation dite hybride du produit. Cette représentation inclut les différents états des composants, que nous nommons textit{as-designed}, textit{as-built} et textit{interface}. Les composants textit{as-built} sont plus particulièrement actualisés de manière à refléter la géométrie du produit physique en cours d’assemblage. Une méthode d’actualisation, s’appuyant sur des données numérisées est proposée. A partir de là, la géométrie de composants dits textit{interfaces} est également actualisée afin de garantir le respect des exigences fonctionnelles sur le produit assemblé. Une méthode d’actualisation est également proposée à cet effet.La faisabilité de l’approche ainsi que des outils proposés est évaluée à travers deux cas d’application, dont un est directement représentatif du contexte industriel des travaux. Les résultats obtenus permettent notamment d’envisager d’enrichir l’approche proposée avec la prise en compte de contraintes non-géométriques dans le but d’optimiser le déroulement des opérations d’assemblageAssembly operations of aerostructures are nowadays planned using the Digital Mock Up of the considered products. To allow a good realization of the aforementioned operations, the geometry of the physical product must remain as faithful as possible to the reference geometry contained in the Digital Mock Up. Because of the complexity of the considered products, unanticipated geometrical deviations may however appear. These geometrical deviations lead to longer cycle times and higher assembly costs.The increasing integration of data processing system gives new prospects on how to organize production systems. These prospects include the possibility to optimize the manufacturing and assembly operations in real time thanks to the use of digital twins of the manufactured products. In this work, we propose the implementation of a geometrical digital twin. This digital twin is capable of mirroring the geometry of the physical product being assembled and optimizing the geometry of some components remaining to be assembled.With this in mind, the initial Digital Mock Up is updated in order to obtain a hybrid representation of the product. This representation includes the different states of the components, which are called as-designed, as-built and interface. The as-built components are more particularly updated in order to mirror the geometry of the physical product being assembled. A method using digitized data is proposed. From there, the geometry of interface components is updated so that the final product complies with the functional requirements which were defined. A method is also proposed for this purpose.The feasibility of the approach as well as the proposed tools is evaluated through two application cases, one of which is directly representative of the industrial context of the works. The obtained results allow to consider enriching the proposed approach by considering non-geometrical constraints in order to optimize assembly operations
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Motoc, Dana. "Development of green composites based on epoxidized vegetable oils (EVOs) with hybrid reinforcements: natural and inorganic fibers." Doctoral thesis, Universitat Politècnica de València, 2017. http://hdl.handle.net/10251/90399.
Full textAbstract:
The main aim of this work id to provide integral methods to predict and characterize the properties of composite structures based on hybrid polymers and reinforcements, that could lead to useful results from an industrial point of view. This is addressed, if possible, by theoretical predictions of the effective properties by using the available experimental data.
The first part is focused on the scientific achievements of the author that allowed a quantitative characterization of the main effective properties of several composite architectures from hybrid polymers and reinforcements, based on bio matrices, tailor-made matrices and different theoretical and simulation methods using computer software to allow good comparison. The second part defines the future research lines to continue this initial investigation.
The main objectives are clearly defined to give the reader a sound background with the appropriate concepts that are specifically discussed in the following chapters. As a main objective, this research work makes a first attempt to provide a systematic analysis and prediction of composite hybrid structures.El objetivo general del trabajo es proporcionar medios integrales para predecir y caracterizar las propiedades de las estructuras de compuestos basados en polímeros y refuerzos híbridos, principales que pueden producir resultados de utilidad práctica simultáneamente. Esto se logra comparando, siempre que sea posible, las predicciones teóricas de las propiedades efectivas con los datos experimentales disponibles. Una primera parte se ocupa de los logros científicos del autor que permitieron caracterizar cuantitativamente las principales propiedades efectivas de las arquitecturas de compuestos basados en polímeros y refuerzos híbridos, basados en matrices bio, auto-desarrollados y diferentes métodos teóricos y de simulación por ordenador utilizados para la comparación. La segunda parte identifica las orientaciones futuras para la evolución y desarrollo de la ciencia y la investigación. Los objetivos generales fueron subrayados y concisos para dar al lector una visión previa de los conceptos que serán discutidos específicamente en los siguientes capítulos. Indirectamente, apuntan hacia uno de los objetivos principales de este trabajo, a saber, proporcionar una dirección para el análisis sistemático de materiales compuestos a base de refuerzos híbridos.
L'objectiu general d'aquest treball es proporcionar els mitjos integrals per tal de predir i caracteritzar les propietats d'estructures de compòsits basats en polímers i reforçaments híbrids, que poden produir resultats amb utilitat pràctica simultàniament. Aquest objectiu s'aconsegueix comparant, sempre que és possible, les prediccions teòriques de les propietats efectives amb les dades experimentals disponibles. Una primera part es centra en els temes científics en què ha treballat l'autor que han permès caracteritzar quantitativament les principals propietats efectives de les arquitectures de compòsits basades en polímers i reforçaments híbrids, derivats de matrius bio, auto-desenvolupats i diferents mètodes teòrics i de simulació informàtica per a una correcta comparació. La segona part identifica les orientacions futures per tal d'establir l'evolució i desenvolupament de la ciència i investigació lligada a la temàtica de la tesi. Els objectius generals han sigut clarament definits per tal de donar-li al lector una visió prèvia i sòlida dels conceptes que es discuteixen en capítols venidors. Indirectament, apunten cap a un dels objectius principals d'aquest treball, a saber, proporcionar una direcció per a l'anàlisi sistemàtica de materials compòsits a base de polímers i reforçaments híbrids.
Motoc, D. (2017). Development of green composites based on epoxidized vegetable oils (EVOs) with hybrid reinforcements: natural and inorganic fibers [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/90399
TESIS
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Pereira, Miguel Ramos. "Time diversity solutions to cope with lost packets." Doctoral thesis, Faculdade de Ciências e Tecnologia, 2012. http://hdl.handle.net/10362/9368.
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A dissertation submitted to Departamento de Engenharia Electrotécnica of Faculdade de Ciências e Tecnologia of Universidade Nova de Lisboa in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Engenharia Electrotécnica e de ComputadoresModern broadband wireless systems require high throughputs and can also have very high Quality-of-Service (QoS) requirements, namely small error rates and short delays. A high spectral efficiency is needed to meet these requirements. Lost packets, either due to errors or collisions, are usually discarded and need to be retransmitted, leading to performance degradation. An alternative to simple retransmission that can improve both power and spectral efficiency is to combine the signals associated to different transmission attempts. This thesis analyses two time diversity approaches to cope with lost packets that are relatively similar at physical layer but handle different packet loss causes. The first is a lowcomplexity Diversity-Combining (DC) Automatic Repeat reQuest (ARQ) scheme employed in a Time Division Multiple Access (TDMA) architecture, adapted for channels dedicated to a single user. The second is a Network-assisted Diversity Multiple Access (NDMA) scheme, which is a multi-packet detection approach able to separate multiple mobile terminals transmitting simultaneously in one slot using temporal diversity. This thesis combines these techniques with Single Carrier with Frequency Division Equalizer (SC-FDE) systems, which are widely recognized as the best candidates for the uplink of future broadband wireless systems. It proposes a new NDMA scheme capable of handling more Mobile Terminals (MTs) than the user separation capacity of the receiver. This thesis also proposes a set of analytical tools that can be used to analyse and optimize the use of these two systems. These tools are then employed to compare both approaches in terms of error rate, throughput and delay performances, and taking the implementation complexity into consideration. Finally, it is shown that both approaches represent viable solutions for future broadband wireless communications complementing each other.
Fundação para a Ciência e Tecnologia - PhD grant(SFRH/BD/41515/2007); CTS multi-annual funding project PEst-OE/EEI/UI0066/2011, IT pluri-annual funding project PEst-OE/EEI/LA0008/2011, U-BOAT project PTDC/EEATEL/ 67066/2006, MPSat project PTDC/EEA-TEL/099074/2008 and OPPORTUNISTICCR project PTDC/EEA-TEL/115981/2009
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Granato, Giovanni. "Optimisation de Lois de Gestion Énergétiques des Véhicules Hybrides." Phd thesis, Ecole Polytechnique X, 2012. http://tel.archives-ouvertes.fr/tel-00788160.
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L'objectif de ce travail consiste à appliquer des techniques de contrôle optimal pour améliorer la performance des lois de gestion d'énergie. Plus précisément, les techniques étudiées sont les solutions de viscosité de l'équation de Hamilton-Jacobi, des méthodes level-set pour l'étude de l'atteignabilité, la programmation dynamique stochastique, la programmation dynamique stochastique duale et les contraintes en probabilité. En premier lieu, ce document débute avec la présentation des outils techniques et modèles nécessaires à l'étude de l'optimisation des lois de gestion d'énergie au sein des véhicules hybrides. En deuxième lieu, nous regardons la synthèse des lois de gestion d'énergie en prenant compte des incertitudes dans le profil de vitesse du véhicule. Dans un premier moment, cette étude porte sur l'utilisation de la programmation dynamique stochastique. Dans un second moment, la programmation dynamique stochastique duale est analysée. Ensuite, nous introduisons une formulation du problème de contrôle optimal avec des contraintes en probabilités, visant la synthèse de lois plus flexibles. En troisième lieu, des résultats théoriques sur l'étude de l'atteignabilité des systèmes hybrides sont démontrés. L'ensemble des états atteignables est caractérisé par une fonction valeur. Nous démontrons ensuite que cette fonction valeur est l'unique solution d'un système d'inégalités quasi-variationnelles dans le sens de la viscosité. Aussi, nous montrons la convergence d'une classe de schémas numériques permettant le calcul de cette fonction valeur. Visant à approfondir l'étude sur l'atteignabilité, nous nous intéressons à une formulation de la dynamique hybride en temps discret, ce qui amène à l'utilisation d'un algorithme directement basé sur la programmation dynamique pour caractériser la fonction valeur. Finalement, nous
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Dang, Weidong. "Finite element modelling of hybrid (spot welded/bonded) joints under service conditions." Thesis, Compiègne, 2015. http://www.theses.fr/2015COMP2187/document.
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Le soudage par point et le collage sont largement utilisés dans la jonction des tôles, telles que l'assemblage de caisses de voiture. Récemment, le soudage par point et le collage ont été combinés pour faire le joint hybride soudé-collé, qui est utilisé pour joindre les aciers à hautes résistances et améliorer la rigidité et la résistance aux chocs des corps de voiture. Dans l'industrie, l'évaluation de la conception avant prototype nécessite des modèles fiables de comportement en termes de prédiction des comportements mécaniques. Le modèle élément finis de joint soudé-collé est un nouveau défi car il doit combiner les modèles de soudage par points et les modèles de collage.Cette thèse se concentre sur la modélisation du joint soudé-collé par de l'acier DP600 et avec l’adhésif structurel SikaPower®-498. La modélisation peur utiliser un modèle solide ou un modèle simplifié (élément coque plus élément de connexion). Le modèle solide permet de prédire le comportement de spécimen à petite échelle: KS2 et cisaillement. Le modèle simplifié peut être utilisé pour prédire la performance des composants de grande dimension avec un coût de calcul acceptable.En ce qui concerne le modèle solide, le comportement du joint soudé et du joint collé sont identifiés séparément calibrés sur un spécimen KS2 sous trajets de chargement différents. Les inhomogénéités dans la zone de fusion et la zone affectée par la chaleur du soudage par point sont prises en compte par l'intermédiaire de facteurs d'échelle applique à la contrainte d'écoulement du métal de base. Les facteurs d'échelle sont determinés par identification inverse. Le modèle de Gurson est utilisé pour prédire la rupture ductile en zone affectée par le chaleur et dans le métal base tandis que le modèle de zone cohésive est utilisé pour simuler la rupture quasi-fragile dans l'interface de la zone de fusion. Les paramètres du modèle de zone cohésive sont identifiés par l'intégrale J à la pointe de fissure de la soudure. Des éléments de zone cohésive avec une loi traction-séparation sont également utilisés pour prédire le décollement adhésif. Les paramètres du modèle sont identifiés par des essais du type « Double Cantilevered Beam » et « End Notched Flexure », correspondant aux mode I et mode II respectivement. Le modèle élaboré pour le soudage par est associé avec le modèle de collage pour prédire le comportement et la rupture du joint soudé-collé.En ce qui concerne le modèle simplifié, des éléments de connexion sont utilisés pour prédire les endommagement des soudure par point. Les paramètres de l'élément de connexion sont identifiés par des tests de KS2 sous différents trajets de chargement. Enfin, les modèles simplifiés d'un soudage, d'un collage, et d'un soudé-collé sont validés sur une jonction en T qui peut représenter le pilier-B de carrosserie de la voitureSpot welding and adhesive bonding are widely used in joining of sheet metals, such as assembling of car body-in-white. Recently, spot weld and adhesive are combined to make weld bonded joint, which is employed to join Advanced High Strength Steel to improve the stiffness and crashworthiness of car body. In industry, the assessment of designing prior to prototype requires reliable constitutive models in terms of the prediction of the mechanical behaviors. The FE model of weld bonded joint is a new challenge as it should combine the models of spot welding and the models of adhesive. This thesis focuses on the modeling of weld bonded joint by DP600 steel and structural adhesive SikaPower®-498. The model of weld bonded joint consists of solid model and simplified model. The former is devoted to predict the behavior of weld bonded joint on small-scale specimen: KS2 and lap-shear. The latter can be used to predict the performance of large components with acceptable computational cost. As regards solid model, spot welded joint and adhesive bonded joint behaviors are separately identified by KS2 specimen under different loading path. The inhomogeneities in fusion zone and heat affected zone of spot weld are taken into account via the scaling of the flow stress of base metal. The scaling factors are calibrated by inverse identification. Gurson model is used to predict ductile fracture in heat affected zone and base metal while cohesive zone model is employed to simulate quasi-brittle fracture in the interface of fusion zone. The parameters of cohesive zone model are identified by the J-integral at the notch tip of spot weld crack. Cohesive zone elements with traction-separation-laws are also used to predict adhesive debonding. Model parameters are calibrated by Double Cantilevered Beam and End Notched Flexure specimens, corresponding to Mode-I and Mode-II fracture respectively. The model developed for spot weld is associated with adhesive model to predict weld bonded joint. As regards simplified model, connector elements are employed to predict the damage of spot weld. The parameters of connector element are identified by KS2 tests under different loading paths. Finally, the simplified model of spot welding, adhesive bonding, and weld-bonding are validated by T-joint which can represent the B-pillar of car body
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Orság, Petr. "Mikropáskové vazební směrové a hybridní členy - laboratorní úloha." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217669.
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The diploma thesis deals with the elaboration of a laboratory experiment with basic types of microstrip directional and hybrid couplers in the frequency range up to tens GHz. The thesis is concerned on branch line directional coupler, rat-race directional coupler, De Rondeho coupler, coupled-line coupler, and Lange directional coupler. Simulated results are confronted with measured results obtained by a skalar network analyzer. From overall findings the relevant laboratory experiment was configured and designed.
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Brahim, El Hacen. "Apport des outils d'optimisation pour l'identification des lois de comportement mécanique des matériaux." Thesis, Lille 1, 2015. http://www.theses.fr/2015LIL10016/document.
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L'objectif de cette thèse est l’implémentation d'algorithmes d'optimisation pour l'identification du comportement mécanique des matériaux. Ces outils sont considérés ici pour automatiser la recherche des paramètres des lois mécaniques implémentés dans un calcul en éléments finis (EF) et diminuer le nombre de calculs nécessaires pour résoudre le problème d’identification. La base de données expérimentale comprend des réponses mécaniques en flexion et en indentation instrumentée qui sont utilisés pour l’identification du comportement d’un biocomposite et d'une variété de métaux. Plusieurs approches d’optimisation ont été développées comprenant des méthodes déterministes, hybrides et stochastiques. Ces méthodes sont évaluées en termes d'efficacité, coût de calcul et précision de l’approche. Le couplage EF-outil d'optimisation s'est avéré efficace et incontournable pour prédire le comportement des matériaux étudiés notamment quand il s'agit d'un essai localThe objective of this work is to implement optimization algorithms for the identification of the mechanical behavior of materials. The tools developed here are intended to automatic search of mechanical parameters that represent variables in a constitutive law implemented in Finite Element (FE) models. The advantage of the implemented tools is the reduction of computational time needed to solve the identification problem. The experimental database includes a variety of mechanical responses in bending and instrumented indentation that are used for the identification the behavior of a biocomposite and a variety of metals. Several optimization approaches are developed in the work including deterministic, stochastic and hybrid methods. These methods are evaluated in terms of efficiency; calculation costs and accuracy. The coupling FE-optimization tool proved to be effective and essential to predict the behavior of the studied materials, especially for instrument indentation
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Mnassri, Radhia. "Réseaux de Petri Lots Triangulaires pour la modélisation mésoscopique et l'étude de la congestion dans le trafic routier." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4376.
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L'usage excessif des routes peut entraîner de nombreux inconvénients dont la pollution, les accidents et la congestion. Une solution accessible à court terme consiste à mettre en œuvre des systèmes de gestion de trafic. Dans ce cadre, nous proposons un formalisme, appelé Réseaux de Petri Lots Triangulaire, qui permet la modélisation et la simulation du trafic routier au niveau mésoscopique comme un système à événements discrets. Le RdPLots Triangulaire permet ainsi de décrire les caractéristiques globales du trafic routier: flux, densité et vitesse à travers la proposition d'une relation flux-densité triangulaire. Cette relation implique une modification de la dynamique des lots. Cette dynamique permet maintenant de représenter les deux états du trafic routier à savoir fluide et congestionné ainsi que les trois régimes dédiés au comportement libre, congestion et décongestion. Le calcul des flux instantanés des transitions est à présent réalisé par une méthode basée sur la technique de programmation linéaire en ajoutant une contrainte qui prend en compte l'état et le régime des lots. Pour modéliser des stratégies de contrôle telles que la variation de la vitesse limite (VSL), nous avons intégré au RdPLots Triangulaire des événements contrôlés qui permettent le changement de la vitesse maximale d'une place lot et le flux maximal d'une transition continue ou lot. Tous ces apports théoriques sont implémentés dans un logiciel que nous avons appelé SimuleauTri, sous lequel nous avons étudié des portions d'autoroute à partir des données réelles. Les résultats de simulation sont proches des mesures effectuées sur le terrain, et montrent la pertinence de RdPLots TriangulaireThe excessive use of roads can cause many adverse effects including pollution, insecurity and congestion. The available short-term solution is the implementation of traffic management systems which optimize the flow and reduce congestion without needing additional infrastructures. In this context, we proposed a new formalism, called Triangular Batches Petri Nets (Triangular BPN), which combines modeling and simulation of traffic in mesoscopic level as a discrete event system. The Triangular BPN describing the overall characteristics of the road traffic such as flow, density, speed by representing a new triangular relation flow-density. This relation implies the modification of batches dynamic, which is now used to represent the two road traffic states : fluid and congested, as well as the three behaviors :free, congestion and decongestion. The calculation of the instantaneous firing flows is achieved by adding a constraint that takes into account the state and behavior of batches. A set of controlled events integrated to the Triangular BPN, that allow the variation of the maximum speed of batch place and the maximum flow of batch and continuous transition. These controlled events used to model the control strategies, such as variable speed limit (VSL). All these theoretical contributions implemented in a software that is called SimuleauTri and used to study a motorway portions from real data. The simulation results are close to the measurements on the ground and show the pertinence of Triangular BPN
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Dubray-Demol, Alexandra. "Adaptation des lois de gestion d’énergie des véhicules hybrides suivant le profil de mission suivi." Grenoble INPG, 2002. https://theses.hal.science/tel-00411430.
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Ce mémoire propose une méthodologie de développement de lois de gestion d’énergie prenant en compte le parcours suivi. L’application concerne un bus hybride de type série, disposant d’une autonomie électrique de quelques kilomètres. La première phase de l’étude a cherché à déterminer la répartition optimale de la puissance demandée par le conducteur entre les deux sources d’énergie, l’organe de stockage temporaire (la batterie) et le générateur électrique (moteur thermique associé à un alternateur). Pour cela, le problème a été formalisé à l’aide de modèles simplifiés des différents composants et résolu par le principe du maximum de Pontryaguine. Les résultats obtenus ont été intégrés dans la commande du véhicule sous forme de cartographies de commande optimale dépendantes d’un unique paramètre K. Ils ont, par ailleurs, nécessité une adaptation pour obtenir des lois de commande implémentables en ligne. Dans la deuxième étape, ces lois de gestion d’énergie ont été modifiées pour prendre en compte le parcours suivi. Trois niveaux de commande, s’appuyant sur l’état de charge de la batterie, ont alors été définis. Le premier niveau qui est directement tiré des travaux d’optimisation précédents correspond à la commande instantanée. Il est paramétré par K pour permettre à la supervision locale (deuxième niveau) de faire suivre à la batterie un profil d’état de charge désiré. Le dernier niveau réalise, quant à lui, l’apprentissage de ce profil d’état de charge désiré à partir de la reconnaissance a priori du parcours suivi. Une fois le parcours effectué, la réalisation obtenue est évaluée et éventuellement intégrée dans les connaissances acquises suivant son degré de reproductibilité. Ces lois de gestion d’énergie ont, dans une dernière étape, été validées par simulation Matlab/Simulink. Pour cela, une campagne d’essais a été effectuée sur un véhicule en situation normale de fonctionnementThesis objectives are to develop a method to construct adaptive energy management strategy for regular driving patterns. The scope is a hybrid bus in a series configuration, with several kilometres of electric driving range. The first step of this study tries to specify the optimal distribution of requested power by the driver between the two sources, the energy storage device (the battery) and the electric generator (an internal combustion engine linked to an alternator). With this aim, the optimisation problem was formalised by using simplified models of the various components. Then, it was solved by the Pontryaguine maximum principle. The result was integrated in the vehicle control in an optimal control mappings form, dependent on a unique parameter K. Moreover, an adaptation was proposed to obtain energy management strategies that can be implemented on-line. In a second step, control was adapted to develop energy management strategy for regular driving pat terns. A three level control was defined from the battery state of charge. The first level, that immediately results from the previous work, corresponds to the instantaneous control. Its parameterisation with K allows the local supervision (the second level) to follow a curve of desired state of charge. In the last level, this curve of desired state of charge is learnt from the a priori recognition of the followed driving pat tern. After the driving pattern execution, the obtained realisation is evaluated and possibly integrated in the knowledge base according to its reproducibility degree. Finally, the adaptive energy management strategy was validated by a Matlab/Simulink model applied to a test campaign acquired with a bus in normal operation conditions