Дисертації: "Solid image"

1

Calmes, Lonnie Kirkland. "Solid-state Raman image amplification." Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/288920.

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Amplification of low-light-level optical images is important for extending the range of lidar systems that image and detect objects in the atmosphere and underwater. The use of range-gating to produce images of particular range bins is also important in minimizing the image degradation due to light that is scattered backward from aerosols, smoke, or water along the imaging path. For practical lidar systems that must be operated within sight of unprotected observers, eye safety is of the utmost importance. This dissertation describes a new type of eye-safe, range-gated lidar sensing element based on Solid-state Raman Image Amplification (SSRIA) in a solid-state optical crystal. SSRIA can amplify low-level images in the eye-safe infrared at 1.556 μm with gains up to 106 with the addition of only quantum-limited noise. The high gains from SSRIA can compensate for low quantum efficiency detectors and can reduce the need for detector cooling. The range-gate of SSRIA is controlled by the pulsewidth of the pump laser and can be as short as 30-100 cm, using pump pulses of 2-6.7 nsec FWHM. A rate equation theoretical model is derived to help in the design of short pulsed Raman lasers. A theoretical model for the quantum noise properties of SSRIA is presented. SSRIA results in higher SNR images throughout a broad range of incident light levels, in contrast to the increasing noise factor with reduced gain in image intensified CCD's. A theoretical framework for the optical resolution of SSRIA is presented and it is shown that SSRIA can produce higher resolution than ICCD's. SSRIA is also superior in rejecting unwanted sunlight background, further increasing image SNR. Lastly, SSRIA can be combined with optical pre-filtering to perform optical image processing functions such as high-pass filtering and automatic target detection/recognition. The application of this technology to underwater imaging, called Marine Raman Image Amplification (MARIA) is also discussed. MARIA operates at a wavelength of 563 nm, which passes most efficiently through coastal ocean waters. The imaging resolution of MARIA in the marine environment can be superior to images produced by laser line scan or standard range-gated imaging systems.

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2

McLean, Alan Stuart. "Transfer matrices and image transport in random media." Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307659.

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3

Lewis, Skigh E. "Laser Levitation of Solid Particles for Combustion and Gasification Applications." Diss., CLICK HERE for online access, 2009. http://contentdm.lib.byu.edu/ETD/image/etd2859.pdf.

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4

Holliman, Nicolas S. "Visualising solid models : an exercise in parallel programming." Thesis, University of Leeds, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277611.

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5

Hjipieris, G. "Millimetre wave six-port reflectometry using image and dielectric guides." Thesis, University of Kent, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354575.

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6

Kalfoutzos, Aristeidis. "Free electron and solid state lasers development for naval directed energy." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Dec%5FKalfoutzos.pdf.

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Thesis (M.S. in Applied Physics and M.S. in Electrical Engineering)--Naval Postgraduate School, December 2002.
Thesis advisor(s): William B. Colson, Phillip E. Pace. Includes bibliographical references (p. 101-102). Also available online.

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7

Goodman, Benjamin T. "Thermodynamic Property Prediction for Solid Organic Compounds Based on Molecular Structure." Diss., CLICK HERE for online access, 2003. http://contentdm.lib.byu.edu/ETD/image/etd300.pdf.

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8

Beutler, Joshua L. "Frequency Response and Gain Enhancement of Solid-State Impact-Ionization Multipliers (SIMs)." Diss., CLICK HERE for online access, 2010. http://contentdm.lib.byu.edu/ETD/image/etd3378.pdf.

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9

Darmiati, Tience. "Maximising the potential for community-based solid waste management in Indonesia /." [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18392.pdf.

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10

Stewart, Nigel Timothy, and nigels@nigels com. "An Image-Space Algorithm for Hardware-Based Rendering of Constructive Solid Geometry." RMIT University. Aerospace, Mechanical and Manufacturing Engineering, 2008. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080721.144757.

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A new approach to image-space hardware-based rendering of Constructive Solid Geometry (CSG) models is presented. The work is motivated by the evolving functionality and performance of computer graphics hardware. This work is also motivated by a specific industrial application --- interactive verification of five axis grinding machine tool programs. The goal is to minimise the amount of time required to render each frame in an animation or interactive application involving boolean combinations of three dimensional shapes. The Sequenced Convex Subtraction (SCS) algorithm utilises sequenced subtraction of convex objects for the purpose of interactive CSG rendering. Concave shapes must be decomposed into convex shapes for the purpose of rendering. The length of Permutation Embedding Sequences (PESs) used as subtraction sequences are shown to have a quadratic lower bound. In many situations shorter sequences can be used, in the best case linear. Approaches to s ubtraction sequence encoding are presented including the use of object-space overlap information. The implementation of the algorithm is experimentally shown to perform better on modern commodity graphics hardware than previously reported methods. This work also examines performance aspects of the SCS algorithm itself. Overall performance depends on hardware characteristics, the number and spatial arrangement of primitives, and the structure and boolean operators of the CSG tree.

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11

MacQueen, Phillip J. "Solid-state image detector development : a linear diode array for astronomical spectroscopy." Thesis, University of Canterbury. Astronomy, 1986. http://hdl.handle.net/10092/8071.

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Future spectroscopic observational programmes at Mount John University Observatory require the ability to acquire spectra with significantly higher spectrophotometric accuracy and geometrical stability than can currently be achieved. Therefore a solid-state linear-diode-array image detector system has been designed and developed for use with the MJUO échelle spectrograph. A review of those electromechanical design techniques of significance to astronomical instrumentation is presented. Their application is exemplified with a complete electromechanical design for the detector, which is found to allow each electronic sub-system implemented within that design to achieve its theoretical level of performance. The requirements for the video processing electronics of a solid-state image detector are explicitly developed, and are used to design the electronics for this detector. Subtle sources of electronic instability which can appear as noise or base-line shifts are identified and controlled in this design. In particular, differential non-linearity is identified in an existing preamplifier design, and so an alternative design is implemented. The readout noise of the entire detector system is measured to be 200 e-/h pairs for a noiseless signal source of zero impedance to ground. This increases to 350 e-/h pairs when the impedance of this source is equal to that of the diode array, due to an additional noise contribution of 290 e-/h pairs. The net readout noise with the RL936F/30 diode array is 450 e-/h pairs, which is the quadratic sum of the detector system noise with the two 210 e-/h pair samples of diode capacitance thermodynamic noise. Thus the diode array is not found to contribute any noise in excess of its theoretical thermodynamic noise. A temperature controller is developed for use with sensors which are cooled in cryogenic dewars. A short term control precision of 1.6 mK r.m.s. is achieved which is entirely due to the theoretical noise of the temperature sensor. The long term precision over all operating conditions is ±20 mK, which is dependent on the design of the dewar. The hardware and software which provide interactive instrument control and data reduction are described. In particular, they provide for flexible control of the detector sub-systems during data acquisition and testing, and enable a high level of data reduction to be undertaken while the detector is integrating. An observational programme has been carried out with this detector sys tern on the southern RS CVn sys tern HR4492. Radial velocity measurements with a precision of ±0.5 km s-¹ have enabled a new ephemeris for the binary motion to be determined, namely HJD = 2446317.5 ± 21.82E. It is used to interpret Hα line profile variations in terms of probable mass transfer within the system.

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12

Rivera, Felipe. "Solid Phase Crystallization of Vanadium Dioxide Thin Films and Characterization Through Scanning Electron Microscopy." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2233.pdf.

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13

Suryani, Eny. "Municipal solid waste management in Indonesia : a case study of semarang municipality /." [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18225.pdf.

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14

Lee, Hong-Wei. "Solid-State Impact-Ionization Multiplier." BYU ScholarsArchive, 2006. https://scholarsarchive.byu.edu/etd/1080.

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This dissertation presents an innovative solid-state current amplifier based on impact-ionization. Unlike avalanche photodetectors which use the same amplification principle, this device can be integrated with any external current source. A discrete amplifier was built on a silicon surface using standard CMOS fabrication processes including lithography, oxidation, ion implantation, diffusion, chemical wet etching, metal deposition, annealing, and rapid thermal processing. Testing was performed by connecting the device to a silicon photodiode, indium-gallium-arsenide photodiodes, and a function generator to demonstrate its compatibility with arbitrary current sources. Current gains above 100 along with pre-amplified leakage currents of less than 10 nA were measured. This amplifier can also be cascaded to achieve very high gains similar to the photomultiplier tube but with much smaller size and no vacuum environment required. Testing was done by amplifying the output signal from an external silicon photodiode. Current gains over 600 were measured when two amplifying devices were cascaded. Additionally, the gain saturation phenomenon of the amplifier due to the space-charge effect is investigated. The measured gain saturation is observed to match very well with the theoretical based predictions. We also present a design rule for obtaining high current gain from the cascaded structure without experiencing gain saturation. Initial bandwidth of the SIM when connected to a silicon photodiode was measured to be about 300 kHz. As we replace the photodiode by a function generator, the bandwidth improved to 450 kHz which is the frequency limit of the system. These results were made on the first generation of SIM devices. We discovered that the space-charge resistance Rsc plays a significant role in determining frequency response. In future generations of the device, we can begin with optimizing the device geometry to reduce this resistance. Also, we can reduce the size of the metal pad and increase the oxide layer thickness to further minimize the device capacitance for faster response. Because of the low-noise gain mechanism employed, this device is of potential interest to a variety of fields requiring high-sensitivity optical or electronic detection.

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15

Hockgraver, Valerie Ruth. "Implementation of ImageActionplus software for improved image analysis of solid propellant combustion holograms." Thesis, Monterey, California. Naval Postgraduate School, 1989. http://hdl.handle.net/10945/27089.

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16

Armishaw, Christopher John. "Controlling cysteine frameworks in structurally constrained conotoxins /." St. Lucia, Qld, 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17491.pdf.

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17

Boonyai, Pilairuk. "Development of new instrumental techniques for measurement of stickiness of solid particulate food materials /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18602.pdf.

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18

O'Sullivan, Cathryn. "Fundamental studies of bacterial cellulose solublisation [sic] during anaerobic digestion of organic solid waste /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19093.pdf.

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19

Maghrabi, Saud M. A. "Algorithms for the removal of hidden edges from computer representations of solid objects." Thesis, University of Hull, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314689.

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20

Bouras, Vasileios. "High energy lasers for ship-defense and maritime propagation." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Dec%5FBouras.pdf.

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Thesis (M.S. in Applied Physics and M.S. in Electrical Engineering)--Naval Postgraduate School, December 2002.
Thesis advisor(s): William B. Colson, Phillip E. Pace. Includes bibliographical references (p. 81-83). Also available online.

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21

Tanner, Matthew Wilder. "Multidimensional Modeling of Solid Propellant Burning Rates and Aluminum Agglomeration and One-Dimensional Modeling of RDX/GAP and AP/HTPB." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2706.pdf.

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22

Siemssen, Brandon Raymond. "Development and Characterization of Friction Bit Joining: A New Solid State Spot Joining Technology Applied to Dissimilar Al/Steel Joints." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2425.pdf.

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23

Abe, Steffen. "Investigation of the influence of different micro-physics on the dynamic behaviour of faults using the lattice solid model /." St. Lucia, Qld, 2001. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16551.pdf.

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24

Lange, Robert. "3D time of flight distance measurement with custom solid state image sensors in CMOS, CCD technology." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=960293825.

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25

Unadkat, Heema. "Investigation of turbulence modulation in solid-liquid suspensions using FPIV and micromixing experiments." Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/6377.

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The focus of this thesis is the study of turbulent solid-liquid stirred suspensions, which are involved in many common unit operations in the chemical, pharmaceutical and food industries. The studies of two-phase flows present a big challenge to researchers due to the complexity of experiments; hence there is a lack of quantitative solid and liquid hydrodynamic measurements. Therefore, an investigation of turbulence modulation by dispersed particles on the surrounding fluid in stirred vessels has been carried out, via two-phase fluorescent Particle Image Velocimetry (FPIV) and micromixing experiments. The main property of interest has been the local dissipation rate, as well as root-mean-square (rms) velocities and turbulent kinetic energy (TKE) of the fluid. Initially a single-phase PIV study was conducted to investigate the flow field generated by a sawtooth (EkatoMizer) impeller. The purpose of this study was to gain insight into various PIV techniques before moving on to more complex two-phase flows. Subsequently stereo-, highspeed and angle-resolved measurements were obtained. The EkatoMizer formed a good case study as information regarding its hydrodynamics is not readily available in literature, hence knowledge has been extended in this area. An analysis of the mean flow field elucidated the general structure of fluid drawn into the impeller region axially and discharged radially; the latter characterised the impeller stream. The radial rms velocity was considered to represent best the system turbulence, even though the tangential rms velocity was greater close to the blade; however the radial component was more prevalent in the discharge stream. Due to differences in rms velocities, TKE estimates obtained from two and three velocity components deviated, being greater in the latter case. Integral (1-D and 2-D) length scales were overestimated by the quantity W / 2 in the impeller region. Ratios of longitudinal-to-lateral length scales also indicated flow anisotropy (as they deviated from 2:1). The anisotropy tensor showed that the flow was anisotropic close to the blade, and returned to isotropy further away from the impeller. Instantaneous vector plots revealed vortices in the discharge stream, but these were not associated with flow periodicity. Alternatively, the vortex structures were interpreted as low frequency phenomena between 0-200 Hz; macro-instabilities were found to have a high probability of occurrence in the discharge stream. Dissipation is the turbulent property of most interest as it directly influences micromixing processes, and its calculation is also the most difficult to achieve. Its direct determination from definition requires highly resolved data. Alternative methods have been proposed in the literature, namely dimensional analysis, large eddy simulation (LES) analogy and deduction from the TKE balance. All methods were employed using 2-D and 3-D approximations from stereo-PIV data. The LES analogy was deemed to provide the best estimate, since it accounts for three-dimensionality of the flow and models turbulence at the smallest scales using a subgrid scale model. (Continues...).

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26

Rifai, Bassel. "Cavitation-enhanced delivery of therapeutics to solid tumors." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:374b2ee1-0711-4994-8434-bf90358d9e47.

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Poor drug penetration through tumor tissue has emerged as a fundamental obstacle to cancer therapy. The solid tumor microenvironment presents several physiological abnormalities which reduce the uptake of intravenously administered therapeutics, including leaky, irregularly spaced blood vessels, and a pressure gradient which resists transport of therapeutics from the bloodstream into the tumor. Because of these factors, a systemically administered anti-cancer agent is unlikely to reach 100% of cancer cells at therapeutic dosages, which is the efficacy required for curative treatment. The goal of this project is to use high-intensity focused ultrasound (HIFU) to enhance drug delivery via phenomena associated with acoustic cavitation. ‘Cavitation’ is the formation, oscillation, and collapse of bubbles in a sound field, and can be broadly divided into two types: ‘inertial’ and ‘stable’. Inertial cavitation involves violent bubble collapse and is associated with phenomena such as heating, fluid jetting, and broadband noise emission. Stable cavitation occurs at lower pressure amplitudes, and can generate liquid microstreaming in the bubble vicinity. It is the combination of fluid jetting and microstreaming which it is attempted to explore, control, and apply to the drug delivery problem in solid tumors. First, the potential for cavitation to enhance the convective transport of a model therapeutic into obstructed vasculature in a cell-free in vitro tumor model is evaluated. Transport is quantified using post-treatment image analysis of the distribution of a dye-labeled macromolecule, while cavitation activity is quantified by analyzing passively recorded acoustic emissions. The introduction of exogenous cavitation nuclei into the acoustic field is found to dramatically enhance both cavitation activity and convective transport. The strong correlation between inertial cavitation activity and drug delivery in this study suggested both a mechanism of action and the clinical potential for non-invasive treatment monitoring. Next, a flexible and efficient method to simulate numerically the microstreaming fields instigated by cavitating microbubbles is developed. The technique is applied to the problem of quantifying convective transport of a scalar quantity in the vicinity of acoustically cavitating microbubbles of various initial radii subject to a range of sonication parameters, yielding insight regarding treatment parameter choice. Finally, in vitro and in vivo models are used to explore the effect of HIFU on delivery and expression of a biologically active adenovirus. The role of cavitation in improving the distribution of adenovirus in porous media is established, as well as the critical role of certain sonication parameters in sustaining cavitation activity in vivo. It is shown that following intratumoral or intravenous co-injection of ultrasound contrast agents and adenovirus, both the distribution and expression of viral transgenes are enhanced in the presence of inertial cavitation. This ultrasound-based drug delivery system has the potential to be applied in conjunction with a broad range of macromolecular therapeutics to augment their bioavailability for cancer treatment. In order to reach this objective, further developmental work is recommended, directed towards improving therapeutic transducer design, using transducer arrays for treatment monitoring and mapping, and continuing the development of functionalized monodisperse cavitation nuclei.

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27

Lin, Qian. "A Plastic-Based Thick-Film Li-Ion Microbattery for Autonomous Microsensors." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1175.pdf.

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28

Zhai, Lailiang. "Gas Chromatography: Mass Spectrometry of Chemical Agents and Related Interferents." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1266.pdf.

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29

Gonzalez, Javier Knauss Wolfgang Gustav. "Full field study of strain distribution near the crack tip in the fracture of solid propellants via large strain digital image correlation and optical microscopy /." Diss., Pasadena, Calif. : California Institute of Technology, 1997. http://resolver.caltech.edu/CaltechETD:etd-12212004-164817.

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30

Tavakoli, Saman. "Construction of a solid 3D model of geology in Sardinia using GIS methods." Thesis, University of Gävle, Department of Technology and Built Environment, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-3773.

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Abstract

3D visualization of geological structures is a very efficient way to create a good understanding of geological features. It is not only an illustrative way for common people, but also a comprehensive method to interpret results of the work. Geologists, geophysics engineers and GIS experts sometimes need to visualize an area to accomplish their researches. It can show how sample data are distributed over the area and therefore they can be applied as suitable approach to validate the result. Among different 3D modeling methods, some are expensive or complicated. Therefore, such a methodology enabling easy and cheap creation of a 3D construction is highly demanded.

However, several obstacles have been faced during the process of constructing a 3D model of geology. The main debate over suitable interpolation methods is the fact that 3D modelers may face discrepancies leading to different results even when they are working with the same set of data. Furthermore, most often part of data can be source of errors, themselves. Hence, it is extremely important to decide whether to omit those data or adopt another strategy. However, even after considering all these points, still the work may not be accurate enough to be used for scientific researches if the interpretation of work is not done precisely. This research sought to explain an approach for 3D modeling of Sedini platform in Sardinia, Italy. GIS was used as a flexible software together with Surfer and Voxler. Data manipulation, geodatabase creation and interpolation test all have been done with aid of GIS. A variety of interpolation methods available in Surfer were used to opt suitable method together with Arc view.

A solid 3D model is created in Voxler environment. In Voxler, in contrary to many other 3D types of software there are four components needed to construct 3D. C value as 4^th component except for XYZ coordinates was used to differentiate special features in platform and do gridding based on chosen value. With the aid of C value, one can mark layer of interest to identify it from other layers.

The final result shows a 3D solid model of the Sedini platform including both surfaces and subsurfaces. An Isosurface with its unique value (Isovalue) can mark layer of interest and make it easy to interpret the results. However, the errors in some parts of model are also noticeable. Since data acquisition was done for studying geology and mineralogy characteristics of the area, there is less number of data points collected per volume according to the main goals of the initial project. Moreover, in some parts of geological border lines, the density of sample points is not high enough to estimate accurate location of lines.

The study result can be applicable in a broad range of geological studies. Resource evaluation, geomorphology, structural geology and GIS are only a few examples of its application. The results of the study can be compared to the results of similar works where different softwares have been used so as to comprehend pros and cons of each as well as appropriate application of each software for a special task.

Keywords: GIS, Image Interpretation, Geodatabase, Geology, Interpolation, 3D Modeling

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31

Tóth, Balázs. "Two-phase flow investigation in a cold-gas solid rocket motor model through the study of the slag accumulation process." Doctoral thesis, Universite Libre de Bruxelles, 2008. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210575.

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The present research project is carried out at the von Karman Institute for Fluid Dynamics (Rhode-Saint-Genèse, Belgium) with the financial support of the European Space Agency.

The first stage of spacecrafts (e.g. Ariane 5, Vega, Shuttle) generally consists of large solid propellant rocket motors (SRM), which often consist of segmented structure and incorporate a submerged nozzle. During the combustion, the regression of the solid propellant surrounding the nozzle integration part leads to the formation of a cavity around the nozzle lip. The propellant combustion generates liquefied alumina droplets coming from chemical reaction of the aluminum composing the propellant grain. The alumina droplets being carried away by the hot burnt gases are flowing towards the nozzle. Meanwhile the droplets may interact with the internal flow. As a consequence, some of the droplets are entrapped in the cavity forming an alumina puddle (slag) instead of being exhausted through the throat. This slag reduces the performances.

The aim of the present study is to characterize the slag accumulation process in a simplified model of the MPS P230 motor using primarily optical experimental techniques. Therefore, a 2D-like cold-gas model is designed, which represents the main geometrical features of the real motor (presence of an inhibitor, nozzle and cavity) and allows to approximate non-dimensional parameters of the internal two-phase flow (e.g. Stokes number, volume fraction). The model is attached to a wind-tunnel that provides quasi-axial flow (air) injection. A water spray device in the stagnation chamber realizes the models of the alumina droplets, which are accumulating in the aft-end cavity of the motor.

To be able to carry out experimental investigation, at first the the VKI Level Detection and Recording(LeDaR) and Particle Image Velocimetry (PIV) measurement techniques had to be adapted to the two-phase flow condition of the facility.

A parametric liquid accumulation assessment is performed experimentally using the LeDaR technique to identify the influence of various parameters on the liquid deposition rate. The obstacle tip to nozzle tip distance (OT2NT) is identified to be the most relevant, which indicates how much a droplet passing just at the inhibitor tip should deviate transversally to leave through the nozzle and not to be entrapped in the cavity.

As LeDaR gives no indication of the driving mechanisms, the flow field is analysed experimentally, which is supported by numerical simulations to understand the main driving forces of the accumulation process. A single-phase PIV measurement campaign provides detailed information about the statistical and instantaneous flow structures. The flow quantities are successfully compared to an equivalent 3D unsteady LES numerical model.

Two-phase flow CFD simulations suggest the importance of the droplet diameter on the accumulation rate. This observation is confirmed by two-phase flow PIV experiments as well. Accordingly, the droplet entrapment process is described by two mechanisms. The smaller droplets (representing a short characteristic time) appear to follow closely the air-phase. Thus, they may mix with the air-phase of the recirculation region downstream the inhibitor and can be carried into the cavity. On the other hand, the large droplets (representing a long characteristic time) are not able to follow the air-phase motion. Consequently, a large mean velocity difference is found between the droplets and the air-phase using the two-phase flow measurement data. Therefore, due to the inertia of the large droplets, they may fall into the cavity in function of the OT2NT and their velocity vector at the level of the inhibitor tip.

Finally, a third mechanism, dripping is identified as a contributor to the accumulation process. In the current quasi axial 2D-like set-up large drops are dripping from the inhibitor. In this configuration they are the main source of the accumulation process. Therefore, additional numerical simulations are performed to estimate the importance of dripping in more realistic configurations. The preliminary results suggest that dripping is not the main mechanism in the real slag accumulation process. However, it may still lead to a considerable contribution to the final amount of slag.

Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished

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32

Nugue, Matthieu. "Outils pour l'étude conjointe par simulation et traitement d'images expérimentales de la combustion de particules d'aluminium utilisées dans les propergols solides." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS229/document.

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L’ajout de particules d’aluminium dans le chargement des moteurs à propergol solide améliore les performances propulsives, mais peut aussi entraîner différents phénomènes néfastes, dont des oscillations de pression. Des travaux de recherche sont réalisés depuis de nombreuses années afin d’améliorer la compréhension de ces phénomènes, notamment par l’utilisation de la simulation numérique. Cependant les données d’entrée de la simulation numérique, en particulier la taille et la vitesse initiale des particules d’aluminium dans l’écoulement, sont souvent difficiles à obtenir pour des propulseurs réels. L’ONERA développe depuis plusieurs années un montage d’ombroscopie permettant de visualiser les particules d’aluminium proches de la surface de petits échantillons en combustion. La présente étude porte sur le développement d’outils pour analyser les images expérimentales du montage d’ombroscopie et améliorer l’interaction avec la simulation numérique diphasique. Une première partie concerne des échantillons de propergol contenant des particules inertes, dont l’intérêt est de permettre de valider les méthodes de mesure sur des images relativement simple et avec des données de référence. Les outils mis en œuvre portent sur la détection et le suivi des particules dans des séquences d’image, ainsi que sur la localisation de la surface du propergol. Une bonne correspondance des distributions de taille a été obtenu avec les distributions de référence. La mise en vitesse des particules quittant la surface a été confrontée à un modèle simplifié de transport de particules dans un écoulement constant. L'utilisation de ce modèle a permis de souligner l'importance de la population de pistes détectées pour bien exploiter un profil de vitesse moyen, en particulier en termes de diamètre moyen. Une simulation numérique diphasique a ensuite été réalisée pour l’expérience d’ombroscopie. Différents paramètres ont été étudiées (type et taille de maillage, paramètres thermodynamiques...) afin d'obtenir un champ stationnaire simulé pour les gaz du propergol. Le mouvement des particules inertes simulées a pu être comparé aux profils expérimentaux pour différentes stratégies d'injection, soit en utilisant un diamètre moyen, soit à partir d’une distribution lognormale. L’autre partie de l'étude est consacrée à l’analyse des images expérimentales de la combustion de particules d’aluminium. La complexité des images dans ces conditions a conduit à utiliser une approche de segmentation sémantique par apprentissage profond, visant à classer tous les pixels de l'image en différentes classes, en particulier goutte d'aluminium et flamme d'aluminium. L’apprentissage a été mené avec une base restreinte d’images annotées en utilisant le réseau U-Net, diverses adaptations pour le traitement des images d’ombroscopie ont été étudiées. Les résultats sont comparés à une technique de référence basée sur une détection d’objets MSER. Ils montrent un net gain à l’utilisation de techniques neuronales pour la ségrégation des gouttes d'aluminium de la flamme. Cette première démonstration de l'utilisation de réseau de neurones convolutifs sur des images d'ombroscopie propergol est très prometteuse. Enfin nous traçons des perspectives côté analyse d’image expérimentales et simulation numériques pour améliorer l’utilisation conjointe de ces deux outils dans l’étude des propergols solides
The addition of aluminum particles in the solid propellant loading improves propulsive performance, but can also lead to various adverse phenomena, including pressure oscillations. Research has been carried out for many years to improve the understanding of these phenomena, particularly through the use of numerical simulation. However, the input data of the numerical simulation, especially the size and the initial velocity of the aluminum particles in the flow, are often difficult to obtain for real rocket motors. ONERA has been developing a shadowgraphy set-up for several years to visualize aluminum particles near the surface of propellant samples in combustion. The present study deals with the development of tools to analyze the experimental images of the shadowgraphy set-up and to improve the interaction with the two-phase digital simulation. A first part concerns propellant samples containing inert particles, which interest is to make it possible to validate the measurement methods on relatively simple images and with reference data. The implemented tools concern the detection and the tracking of particles in image sequences, as well as the location of the surface of the propellant. Good correspondence of size distributions was obtained with reference distributions. The velocity of particles leaving the surface has been confronted with a simplified model of particle transport in a constant flow. The use of this model has made it possible to emphasize the importance of the population of detected tracks in order to make good use of an average velocity profile, particularly in terms of average diameter. A two-phase flow simulation was then carried out for the shadowgraphy experiment. Different parameters were studied (type and size of mesh, thermodynamic parameters ...) in order to obtain a simulated stationary field for propellant flow. The movement of the simulated inert particles could be compared to the experimental profiles for different injection strategies, either using a mean diameter or using a lognormal distribution. The other part of the study is devoted to the analysis of experimental images of the combustion of aluminum particles. The complexity of the images under these conditions has led to the use of a deep learning semantic segmentation approach, aiming to classify all the pixels of the image into different classes, in particular aluminum droplet and flame. The learning was conducted with a restricted base of annotated images using the U-Net neural network, with various adaptations on the processing of the experimental images were studied. The results are compared to a reference technique based on MSER object detection. They show a clear gain in the use of neural techniques for the segregation of aluminum drops of the flame. This first demonstration of the use of convolutional neuronal network on propellant shadowgraphy images is very promising. Finally, we draw perspectives on experimental image analysis and numerical simulation to improve the joint use of these two tools in the study of solid propellants

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33

BOUDH-HIR, MOHAMED ESSALAH. "Contribution a l'etude theorique de la structure et de la thermodynamique d'un fluide polaire au voisinage d'une surface." Paris 6, 1987. http://www.theses.fr/1987PA066040.

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Le profil position-orientation donne par les approximations type msa, lhnc. . . Est identique a celui des spheres dures. Il est montre que, meme dans ce cas, il existe des orientations privilegiees. Loin de la surface, seul le potentiel image classique subsiste. Au voisinage de celle-ci, le resultat est plus complique et ne peut etre prevu par la theorie classique. Il est montre aussi qu'un potentiel anisotrope faible ( equiv. A kt) suffit pour produire des effets observables sur le plan experimental. Deux approximations ont ete comparees: blip et l'inegalite de gibbs-bogolioubov. Enfin, etude des fonctions de correlation de paire: il est montre que, sur la surface et loin de celle-ci, ces fonctions sont decrites par les potentiels direct et image. Dans la region intermediaire, la solution est plus compliquee

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34

Perelstein, Yuri. "Investigation of Erosive Flow Injected Through Apertures into a Narrow Annulus." University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1463073062.

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35

Assali, Pierre. "Modélisation géostructurale 3D de parois rocheuses en milieu ferroviaire : application aux ouvrages en terre." Thesis, Strasbourg, 2014. http://www.theses.fr/2014STRAD009.

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Ce travail de thèse vise une optimisation des méthodologies de modélisation géostructurale, permettant d'aboutir à une meilleure gestion des aléas rocheux affectant le système ferroviaire. La caractérisation géométrique des massifs rocheux est entreprise grâce à une classification des modèles en sous-ensembles correspondant aux principales familles de discontinuités. En parallèle de cette caractérisation automatisée, une seconde approche dite manuelle a été examinée. Cette approche combine données tridimensionnelles (nuages de points denses) et support photographique (images 2D). Les données sur les discontinuités planaires, traditionnellement acquises manuellement en certains points nécessairement accessibles du massif, résultent désormais de l'analyse des modèles couvrant l'ensemble de l'ouvrage. Ce projet a permis le développement d'un outil de modélisation améliorant la connaissance du patrimoine rocheux sans engager la sécurité du personnel, ni la capacité de la ligne ferroviaire
This project aims at an optimization of geostructural modeling methodolgies, leading to a better knowledge and a better management of the rock risk impacting the railway system. Acquired 3D models are exploited in order ton convert 3D point clouds into geostructural analysis. Hence, we have developed a semi-automatic process that allows 3D models to be combined with the results of field surveys in order to provide more precise analyses of rock faces, for example, by classifying rock discontinuities into subsets according to their orientation. A second approach is proposed, combining both 3D point clouds (from LiDAR or image matching) and 2D digital images. Combining these high-quality data with the proposed automatic and manual processing method greatly improves the geometrical analysis of rock faces, increases the reliability of structural interpretations, and enables reinforcement procedures to be optimized

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36

Winder, Brian Geoffrey. "Achieving Complex Motion with Fundamental Components for Lamina Emergent Mechanisms." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2279.pdf.

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37

Lopes, Tito Souza Filippo. "Análise da aplicabilidade de sistema mini-VANT comercial no diagnóstico da geração de resíduos de desastres no Brasil." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/6/6139/tde-20082018-141639/.

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A necessidade de minimizar os impactos causados por desastres, e pelos resíduos sólidos neles gerados, motivaram o desenvolvimento da gestão de resíduos de desastres em todo o mundo. Plataformas de sensoriamento remoto orbital e aeronaves tripuladas vêm sendo empregadas no auxílio à gestão de desastres e de seus resíduo, ainda que de forma restrita a casos mais extremos. O desenvolvimento tecnológico dos veículos aéreos não tripulados (VANTs), em especial os modelos civis comerciais de baixo custo, e a formulação da legislação que trata do seu uso, tem viabilizado sua aplicação em distintas áreas, dentre elas o mapeamento de precisão. A fim de analisar a aplicabilidade dessas plataformas de auxilio ao diagnóstico da geração de resíduos de desastres, foram selecionados dois conjuntos fotografias previamente obtidos com um VANT comercial quadrirotor. Em seguida, foi realizado o processamento desses dados no PhotoScan, visando a geração de mapas informativos. Buscou-se analisar a capacidade de identificação, quantificação e caracterização dos resíduos sólidos dispostos nas áreas mapeadas. Aspectos legais, econômicos e técnicos associados ao uso da ferramenta foram contemplados, afim de melhor fundamentar a aplicabilidade em questão. Os resultados indicaram relevante potencial de identificação e quantificação dos resíduos encontrados, e algumas limitações na capacidade de caracterizá-los. A atual legislação, e os aspectos econômicos e técnicos levantados favorecem a utilização de mini-VANT comercial para o uso proposto, ainda que de forma limitada à desastres onde a extensão afetada não seja demasiadamente extensa. A observância às boas praticas na escolha do equipamento, no planejamento e execução de vôo são fundamentais para a geração de mapas informativos contendo o posicionamento, o volume estimado e a composição estimada dos montes de resíduos encontrados.
The need to minimize the impacts caused by disasters, and the solid waste generated, motivated the development of methods and practices for the management of disaster residues all over the world. Orbital remote sensing platforms and manned aircraft have been used in the management of disasters and their residues, even though it restricts them to the most extreme cases. The technological development of unmanned aerial vehicles (UAVs), especially low-cost commercial civil models, and the formulation of legislation that deals with their use, has made their application viable in different areas, including precision mapping. In order to analyze the applicability of these platforms in aid of the diagnosis of disaster waste generation, two sets of photographs previously obtained with an \"off the shelf\" UAV were selected. Then, the processing of these data in PhotoScan was carried out, aiming at the generation of informative maps. It was sought to analyze the capacity of identification, quantification and characterization of the solid residues disposed in the mapped areas. Legal, economic and technical aspects associated to the use of the tool were contemplated, in order to better base the applicability on the question. The results indicated relevant potential of identification and quantification of the residues found, and some limitations in their capacity of characterization. The current legislation, and the economic and technical aspects raised favor the use of commercial mini-VANT for the proposed use, even though in a limited way to disasters where the affected extension is not too extensive. The observance of good practices in the choice of equipment, in the planning and execution of its execution are fundamental for the generation of informative maps containing the positioning, the estimated volume and the estimated composition of the amounts of residues found.

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38

Rayner, Anton. "Laser cooling of solids /." St. Lucia, Qld, 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16448.pdf.

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39

Hassen, Barkai Allatchi. "Caractérisation d’un écoulement diphasique dans un airlift sous dépression. Application pour l’extraction des matières solides en suspension." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI038.

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Les colonnes à bulles sont des contacteurs gaz-liquide très répandus en milieu industriel, notamment dans des applications de procédés chimiques, biologiques et minéralogiques. Dans la gamme de colonne à bulles disponible, l'airlift sous dépression est une innovation française présentant des caractéristiques très intéressantes pour le pompage hydraulique, le transfert de masse et la séparation des matières en suspension. Ce travail de thèse s'inscrit dans le cadre du développement de cet airlift amélioré, très utilisé dans le milieu industriel. L'objectif de la thèse est la caractérisation hydrodynamique de la colonne airlift sous dépression et l'analyse de ses capacités à assurer la fonction de séparation solide-liquide pour des particules en suspension. Le travail est exclusivement expérimental et le dispositif expérimental est constitué d'une colonne à bulles verticale transparente en plexiglass soumise à une dépression en tête et connectée à un bassin de recirculation hydraulique. L'analyse hydrodynamique a été réalisée à l'aide de capteur de pression différentielle pour l'étude globale et à l'aide d'une double sonde optique pour une caractérisation locale. Les résultats obtenus ont permis d'étudier le régime d'écoulement pour les principaux paramètres : le taux de vide, la vitesse d'ascension et le diamètre des bulles. La Vélocimétrie par Images des Particules a été appliquée pour visualiser et analyser les structures d'écoulement dans le bassin de recirculation. Les capacités extractives de la colonne ont été étudiées en eau douce avec ajout de produits tensioactifs. La caséine soluble et le Methyl Iso Butyl Carbinol (MIBC) sont les deux tensioactifs qui ont donné les meilleurs résultats en termes de séparation solide-liquide des matières en suspension. Ce travail a contribué à la compréhension de l'hydrodynamique des airlift sous dépression et a permis de mettre en évidence les potentialités de cette colonne dans le processus de séparation solide-liquide. Le travail ouvre aussi la voie à la modélisation numérique de l'hydrodynamique de la colonne en s'appuyant sur les résultats expérimentaux
Bubble columns are gas-liquid contactors widely used in industry, especially in chemical, biological and mineralogical process applications. In the range of bubble columns available, the vacuum airlift is a French innovation with very interesting characteristics for hydraulic pumping, mass transfer and suspended matter separation. This thesis work is part of the development of this improved airlift, which is widely used in the industrial environment. The objective of the thesis is the hydrodynamic characterization of the airlift column under vacuum and analysis of its capacities to ensure the solid-liquid separation function. This work is exclusively experimental and the experimental setup is a vertical bubble column in plexiglass under vacuum and connected to a recirculation basin. The hydrodynamic analysis was carried out using a differential pressure sensor for the global study and using a double optical probe for local characterization. Results obtained made it possible to study flow regime. The main parameters obtained are the void fraction, superficial velocity and bubbles diameter. Particle Image Velocimetry is applied to visualize and analyze the flow structures in the recirculation basin. The extracting capacities of the column were studied in tap water with the addition of surfactants. Soluble casein and Methyl Iso Butyl Carbinol (MIBC) are the two surfactants that have given the best results in terms of solid-liquid separation of suspended matter. This work contributed to the understanding hydrodynamics for vacuum airlift column and helped to highlight the potential of this column in the solid-liquid separation process. This work also opens the way to numerical modelling of airlift column hydrodynamics from experimental results

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40

Yang, Chen Yang. "PHOTOMULTIPLICAITON EFFECT IN ORGANIC AND QUANTUM DOT PHOTODETECTOR AND DEVICE STRUCTURAL MOTIFICATION." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1495318625625402.

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41

Ding, Li Ping. "Multicomponent adsorption in heterogeneous microporous solids /." [St. Lucia, Qld.], 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16729.pdf.

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42

Li, Qin. "Simulations of dynamic behaviour of packed particulate systems : applications of discrete element methods /." [St. Lucia, Qld.], 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16731.pdf.

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43

Jagnow, Robert Carl 1976. "Stereological techniques for synthesizing solid textures from images of aggregate materials." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/30164.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, February 2005.
Includes bibliographical references (leaves 121-130).
When creating photorealistic digital scenes, textures are commonly used to depict complex variation in surface appearance. For materials that have spatial variation in three dimensions, such as wood or marble, solid textures offer a natural representation. Unlike 2D textures, which can be easily captured with a photograph, it can be difficult to obtain a 3D material volume. This thesis addresses the challenge of extrapolating tileable 3D solid textures from images of aggregate materials, such as concrete, asphalt, terrazzo or granite. The approach introduced here is inspired by and builds on prior work in stereology--the study of 3D properties of a material based on 2D observations. Unlike ad hoc methods for texture synthesis, this approach has rigorous mathematical foundations that allow for reliable, accurate material synthesis with well-defined assumptions. The algorithm is also driven by psychophysical constraints to insure that slices through the synthesized volume have a perceptually similar appearance to the input image. The texture synthesis algorithm uses a variety of techniques to independently solve for the shape, distribution, and color of the embedded particles, as well as the residual noise. To approximate particle shape, I consider four methods-including two algorithms of my own contribution. I compare these methods under a variety of input conditions using automated, perceptually-motivated metrics as well as a carefully controlled psychophysical experiment. In addition to assessing the relative performance of the four algorithms, I also evaluate the reliability of the automated metrics in predicting the results of the user study. To solve for the particle distribution, I apply traditional stereological methods.
(cont.) I first illustrate this approach for aggregate materials of spherical particles and then extend the technique to apply to particles of arbitrary shapes. The particle shape and distribution are used in conjunction to create an explicit 3D material volume using simulated annealing. Particle colors are assigned using a stochastic method, and high-frequency noise is replicated with the assistance of existing algorithms. The data representation is suitable for high-fidelity rendering and physical simulation. I demonstrate the effectiveness of the approach with side-by-side comparisons of real materials and their synthetic counterparts derived from the application of these techniques.
by Robert Carl Jagnow.
Ph.D.

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44

Bowler, Adam I. "Strain Measurement in Solids using Ultrasonic Array Speckle Images." Thesis, University of Bristol, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.525470.

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45

Lee, Yeaw-Lip. "Particle-sizing system fro scanning electron microscope images of solid-propellant combustion exhaust." Thesis, Monterey, California. Naval Postgraduate School, 1991. http://hdl.handle.net/10945/28440.

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46

Fening, Stephen D. "The Creation of Solid Models of the Human Knee from Magnetic Resonance Images." Ohio University / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1056734979.

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47

Arthington, Matthew Reginald. "Photogrammetric techniques for characterisation of anisotropic mechanical properties of Ti-6Al-4V." Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:51e4f4d9-75e2-4784-9fbf-103d07496e23.

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The principal aims of this research have been the development of photogrammetric techniques for the measurement of anisotropic deformation in uniaxially loaded cylindrical specimens. This has been achieved through the use of calibrated cameras and the application of edge detection and multiple view geometry. The techniques have been demonstrated at quasi-static strain rates, 10^-3 s^-1, using a screw-driven loading device and high strain rates, 10^3 s^-1, using Split Hopkinson Bars. The materials that have been measured using the technique are nearlyisotropic steel, anisotropic cross-rolled Ti-6Al-4V and anisotropic clock-rolled commercially pure Zr. These techniques allow the surface shapes of specimens that deform elliptically to be completely tracked and measured in situ during loading. This has allowed the measurement of properties that could not have been recorded before, including true direct stress and the ratio of transverse strains in principal material directions, at quasi-static and elevated strain rates, in tension and compression. The techniques have been validated by measuring elliptical prisms of various aspect ratios and independently measuring interrupted specimens using a coordinate measurement machine. A secondary aim of this research has been to improve the characterisation of the anisotropic mechanical properties of cross-rolled Ti-6Al-4V using the techniques developed. In particular, the uniaxial yield stresses, hardening properties and the associated anisotropic deformation behaviour along the principal material directions, have all been recorded in detail not seen before. Significant findings include: higher yield stresses in-plane than in the through-thickness direction in both tension and compression, and the near transverse-isotropy of the through-thickness direction for loading conditions other than quasi-static tension, where significant anisotropy was observed.

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48

Lim, Kok Seng. "Digital image analysis study of bubbling, solids mixing and segregation in fluidized beds /." Title page, contents and summary only, 1992. http://web4.library.adelaide.edu.au/theses/09PH/09phl73212.pdf.

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49

Moya, Álvarez Carlos. "Structure versus Magnetism in Magnetic Nanoparticles." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/384539.

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From the fundamental point of view, NPs formed by MFe2O4 with (M= Co, Fe) are ideal system models to study the new magnetic phenomena associated with the so-called particle-like behaviour, which emerges from the size reduction towards the nanometre scale and contrasts with the well-established magnetic properties of their bulk-counterparts. It is well known that most of the particle-like behaviour and in general the large variability of the magnetic properties observed in this kind of nanomaterials are related to structural features of the NPs rather than being originated from intrinsic finite-size or surface effects, at least for NPs bigger than a few nanometers. These structural features, such as crystallographic defects, polycrystalline nature of the NPs, lack of crystallinity at the particle surface, etc., have strong influence on their magnetic properties and can be modified at will through the synthesis method. Therefore, whenever this particle-like behaviour is unwanted for applications with highly demanding requirements, the choice of a suitable synthesis method is of key importance to obtain NPs of high-crystalline quality. On the contrary, particle-like behaviour controlled by the crystalline nature of the NPs could be useful to tailor their magnetic properties for specific applications. Among the common synthesis methods, high-temperature decomposition of metal-organic precursors results the best alternative due to the remarkable final properties of the obtained NPs, such as narrow size distribution, high crystallinity and relatively simple tuning of their size and shape. So this will be the chemical route chosen in this work to study the capabilities of this synthesis method to control the final properties of the NPs through their nanostructure. In addition, to get a deeper insight in the magnetic and structural properties of those materials and to shed light on relevant issues that are still under discussion (dynamic response, magnetic frustration or inter¬particle interactions) it could be useful to combine experimental techniques enabling the characterization of the system from macroscopic scales towards single-particle structures. Within this framework, we present this work that is divided into three main parts. First, it is studied the effect of the concentration of two common reactants, involved in the thermal decomposition method, on the final properties of magnetic NPs based on iron oxides aiming at optimizing the synthesis procedure and getting a good control of the structure of the final product. In the second part, those NPs obtained in the former way are applied to demonstrate the crucial role of the nanostructure on the physical properties of nanoparticulate systems; specially, the strong interplay existent between structure and both magnetic frustration and interparticle interactions. Finally, in the third part, MFM experiments with an external applied magnetic field have been performed to directly observe the reversal of the magnetization of isolated particles and the dynamic behaviour of small aggregates.

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50

Marchand, Olivier. "Etude du procédé de projection plasma de suspensions pour l'élaboration de piles à combustible à oxyde solide." Phd thesis, Université de Technologie de Belfort-Montbeliard, 2010. http://tel.archives-ouvertes.fr/tel-00597338.

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Augmenter la durée de vie des piles à combustible de type SOFC en abaissant leur température de fonctionnement tout en maintenant un prix de fabrication raisonnable est un des enjeux du secteur énergétique. Ces travaux de recherche entrent dans ce cadre par l'utilisation de la projection plasma de suspensions pour fabriquer des couches céramiques ou cermets finement structurées sur support métallique poreux. Dans cet objectif, la compréhension du procédé s'est avérée être une étape indispensable. A cette fin l'utilisation de la Vélocimétrie par Image de Particules spécialement adaptée aux contraintes de la projection plasma a permis une meilleure caractérisation des jets injectés mais aussi une compréhension plus poussée des phénomènes régissant le traitement des particules. Fort de ces informations, les couches composant le cœur de pile ont été élaborées : l'anode et l'électrolyte, constituée respectivement d'un cermet nickel-zircone yttriée et de zircone yttriée et enfin la cathode composée d'un conducteur mixte La2NiO4.

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