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Vinagrero, Gutierrez Sergio. "Méthodologies pour la Conception, la Modélisation et l'Évaluation de la Qualité des Fonctions Physiques Non Clonables (PUFs)". Electronic Thesis or Diss., Université Grenoble Alpes, 2024. http://www.theses.fr/2024GRALT063.
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Les Fonctions Physiques Non-Clonables (PUFs) représentent une alternative prometteuse aux méthodes cryptographiques conventionnelles pour sécuriser les données sensibles dans les circuits modernes en générant des secrets uniques à la volée, en tirant parti de la variabilité inhérente des processus et en éliminant le besoin de stockage des données. Les PUF basées sur les oscillateurs en anneau et la SRAM sont particulièrement étudiées en raison de leur simplicité et de leur prévalence dans les systèmes sur puce (SoC).Lors des simulations paramétriques pour l'évaluation des PUF, plusieurs limitations des logiciels commerciaux de conception électronique assistée par ordinateur (EDA) ont été identifiées. Pour répondre à ces défis, une série d'outils open-source ont été développés, tels que Monaco et NIMPHEL, pour simplifier et accélérer le processus de conception et d'évaluation par des méthodologies de simulation.Pour valider les résultats des simulations, une plateforme open-source, SRAMPlatform, a été créée pour recueillir des données étendues de SRAM et des lectures de capteurs provenant de microcontrôleurs. La plateforme collecte des données de 84 microcontrôleurs STM32, avec des mises à jour hebdomadaires stockées dans une base de données en libre accès, répondant ainsi à la rareté des ensembles de données accessibles sur les PUF. De plus, un ensemble de données complet fourni par Infineon a offert des informations précieuses pour valider les hypothèses de simulation et explorer de nouvelles conceptions de PUF.En outre, des limitations significatives dans les métriques de performance standard des PUF ont été notées et plusieurs solutions et nouvelles métriques alternatives pour une évaluation plus robuste sont proposées. Les données réelles provenant de la plateforme SRAM ont montré des biais extrêmes et des effets de corrélation que les métriques canoniques n'ont pas mis en évidence, soulignant la nécessité de méthodologies de test plus robustes pour identifier avec précision ces effets. Une attention particulière a été portée sur la relation entre l'entropie et la fiabilité des PUF, conduisant au développement d'une méthodologie basée sur la simulation pour établir des seuils de fiabilité basés sur les différences de fréquence. Par la suite, un modèle mathématique holistique prenant en compte la variabilité des processus a été créé pour optimiser les conceptions de RO-PUF, et une nouvelle méthodologie de conception, "Split PUF", a été introduite pour maximiser le rendement en entropie et la fiabilité.La modélisation mathématique des PUFs, un domaine moins exploré, est également investiguée, en proposant des méthodologies statistiques et numériques pour améliorer la compréhension des conceptions de PUF basées sur RO et SRAM. Des méthodes statistiques pour l'extrapolation des métriques sont introduites, réduisant le temps et le coût nécessaires pour évaluer les PUFs. En outre, des jumeaux numériques de PUFs sont proposés, facilitant le test et l'évaluation des algorithmes. Ces modèles offrent une méthodologie robuste et rentable pour évaluer les performances des PUF et aider à leur évaluation de sécurité.Ces avancées améliorent les méthodologies d'évaluation des PUF, en répondant aux limitations des outils et des métriques actuels, et en fournissant de nouveaux cadres et modèles pour la recherche future. Les travaux futurs incluent le développement d'un cadre de test unifié pour toutes les familles de PUF, la validation des modèles statistiques sur un spectre plus large de familles de PUF, le raffinement des modèles de jumeaux numériques, et l'extension du concept de Split PUF à de nouvelles familles de PUF. Ces orientations de recherche visent à accélérer l'adoption mondiale des technologies PUF en améliorant les méthodologies d'évaluation, en répondant aux limitations actuelles des outils et des métriques, et en fournissant de nouveaux cadres et modèles pour la recherche futurePhysical Unclonable Functions (PUFs) are a promising alternative to conventional cryptographic methods for securing sensitive data in modern circuits by generating unique secrets on the fly, leveraging inherent process variability and eliminating the need for data storage. Ring Oscillator and SRAM-based PUFs are particularly studied due to their simplicity and prevalence in System-on-Chips (SOCs).During the parametric simulations for PUF evaluation, several limitations in available commercial Electronic Design Automation (EDA) software were identified. To address these challenges, a series of open-source tools were developed, such as Monaco and NIMPHEL, to simplify and accelerate the design process and evaluation through simulation methodologies.To validate the simulation results, an open-source platform, SRAMPlatform, was created to gather extensive SRAM data and sensor readings from microcontrollers. The platform gathers data from 84 STM32 microcontrollers, with weekly updates stored in an open-access database, addressing the scarcity of accessible PUF datasets. Additionally, a comprehensive dataset from Infineon provided valuable insights for validating simulation hypotheses and exploring new PUF designs.Furthermore, significant limitations in standard PUF performance metrics are noted and several mitigations and new alternative metrics for more robust evaluation are proposed. Real-world data from the SRAM platform showed extreme bias and correlation effects that the canonical metrics failed to highlight, underscoring the need for more robust testing methodologies to accurately identify these effects. A major focus was placed on the relationship between entropy and reliability in PUFs, leading to the development of a simulation-based methodology for setting reliability thresholds based on frequency differences. Subsequently, a holistic mathematical model accounting for process variability was created to optimize RO-PUF designs, and a new design methodology, "Split PUF," is introduced to maximize entropy yield and reliability.The mathematical modeling of PUFs, a less-explored area is also investigated, by proposing statistical and numerical methodologies to improve understanding of RO and SRAM-based PUF designs. Statistical methods for metric extrapolation are introduced, reducing the time and cost needed to evaluate PUFs. Furthermore, digital twins of PUFs are proposed, facilitating algorithm testing and evaluation. These models provide a robust and cost-effective methodology for assessing PUF performance and aid in their security assessment.These advancements enhance PUF assessment methodologies, addressing limitations in current tools and metrics, and providing new frameworks and models for future research. Future work includes developing a unified testing framework for all PUF families, validating statistical models across a wider spectrum of PUF families, refining the digital twin models, extending the concept of Split PUFs to new PUF families. These research directions aim to accelerate the worldwide adoption of PUF technologies by enhancing assessment methodologies, addressing current tool and metric limitations, and providing new frameworks and models for future research
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Pundir, Nitin K. Pundir. "Design of a Hardware Security PUF Immune to Machine Learning Attacks". University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1513009797455883.
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Herkert, Nicholas John. "Development of the polyurethane foam passive air sampler for novel applications in ambient air across the globe". Diss., University of Iowa, 2018. https://ir.uiowa.edu/etd/6130.
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Our understanding about the presence, behavior, and toxicities of atmospheric persistent organic pollutants is limited by our ability to accurately measure them. This dissertation details the development and characterization of a model for the determination of an accurate sampling rate (Rs), and effective sampling volume (Veff), for polyurethane equipped passive air samplers (PUF-PAS), and the subsequent application of PUF-PAS sampling methods towards novel applications studying polychlorinated biphenyls (PCBs).
The user friendly mathematical model resulting from this work, published as a Matlab script, predicts Rs and Veff as a function of local hourly meteorology and the physical-chemical properties of the target analytes. The model was first developed using active sampling methods in urban Chicago, where good agreement was found between the PUF-PAS and high volume active samplers: Active/Passive = 1.1 ± 1.2. The model was then expanded and calibrated globally using the dataset from the Global Atmospheric Passive Sampling (GAPS) network. After this global calibration we found acceptable agreement between modelled and depuration-determined sampling rates for an independent dataset, with several compounds having near zero mean percent bias (±6%). The globally applicable model is the best alternative for locations experiencing low average wind speeds or cold temperatures, and is particularly useful for the interpretation of samples with long deployments, deployments conducted under warming conditions, and compounds with high volatility. An interactive web-based graphical user interface for the sampling rate model was developed. Users input sampler locations, deployment dates, and target chemicals, in the web-interface and are provided with a sample and compound specific Rs and Veff.
The sampling rate model was examined for use in the indoor environment and it was found that both the experimentally calibrated (1.10 ± 0.23 m3 d-1) and modeled (1.08 ± 0.04 m3 d-1) Rs agreed with literature reports. Correlating sample specific wind speeds with uptake rates, it was determined that variability of wind speeds throughout the room significantly (p-value < 0.001) affected uptake rates. Despite this, the PUF-PAS concentration measurements using modelled Rs values were within 27% of the active sampling determined concentration measurements.
Using PUF-PAS samplers, PCBs 47, 51, and 68 were found to account for up to 50% of measured indoor sum PCB concentration (2700 pg m-3). Direct surface measurements were conducted to identify finished cabinetry to be a major source, as a result of the decomposition of 2,4-dichlorobenzoyl peroxide used as an initiator in free-radical polymerization of polyester resins. While this phenomenon has been detected at trace levels in other polymer products, it has never been shown to be a significant environment source of PCBs.
PUF-PAS samplers were similarly used to study the presence of airborne hydroxylated polychlorinated biphenyls (OH-PCBs) and PCBs in the metropolitan Chicago area. While OH-PCBs have been hypothesized to be an important removal mechanism for atmospheric PCBs, they were not directly measured in the air until recently. The two most frequently detect OH-PCB congeners in this study, 2OH-PCB2 and 6OH-PCB2, were detected at levels comparable to a previous report of atmospheric OH-PCBs utilizing active sampling methods, suggesting the viability of PUF-PAS methods to study atmospheric OH-PCBs. One sampling site detected as many as 50 OH-PCBs but uncertainties with sampling and laboratory methods prevent any strong conclusions from being drawn.
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Lemire, Garlic Nicole. "NLG Thesis Appendices Final 5 12 17.pdf". Master's thesis, Temple University Libraries, 2017. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/452949.
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Media Studies & ProductionM.A.
The analysis of mainstream newspaper content has long been mined by communication scholars and researchers for insights into public opinion and perceptions. In recent years, scholars have been examining African-American authored periodicals to obtain similar insights. Hearkening back to the 1950s and 1960s civil rights movement in the United States, the highly-publicized killings of African-American men by police officers during the past several years have highlighted longstanding strained police-community relations. As part of its role as both a reflection of, and an advocate for, the African-American community, African-American journalistic texts contain a wealth of data about African-American public opinion about, and perceptions of, police. In years past, media content analysts would manually sift through newspapers to divine interesting police-related themes and variables worthy of study. But, with the exponential growth of digitized texts, communication scholars are experimenting with computerized text analysis tools like topic modeling software to aid them in their content analyses. This thesis considers to what degree topic modeling software can be used at the exploratory stage of designing a content analysis study to aid in uncovering themes and variables worthy of further investigation. Appendix A contains results of the manual exploratory content analysis. The list of topics generated by the topic modeling software may be found in Appendix B.
Temple University--Theses
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Bakosi, József. "PDF modeling of turbulent flows on unstructured grids". Fairfax, VA : George Mason University, 2008. http://hdl.handle.net/1920/3083.
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Thesis (Ph.D.)--George Mason University, 2008.Vita: p. 178. Thesis director: Zafer Boybeyi. Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Computational Sciences and Informatics. Title from PDF t.p. (viewed June 30, 2008). Includes bibliographical references (p. 168-177). Also issued in print.
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Matheson, Tomas. "Presumed pdf modelling for turbulent spray combustion". Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/413770/.
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Zhu, Min. "Modelling and simulation of spray combustion with PDF methods". Thesis, University of Cambridge, 1996. https://www.repository.cam.ac.uk/handle/1810/272496.
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Khan, Md Kaisar. "NUMERICAL MODELING OF WAVE PROPAGATION IN NONLINEAR PHOTONIC CRYSTAL FIBER". Doctoral diss., University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4096.
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In this dissertation, we propose numerical techniques to explain physical phenomenon of nonlinear photonic crystal fiber (PCF). We explain novel physical effects occurred in PCF subjected to very short duration pulses including soliton. To overcome the limitations in the analytical formulation for PCF, an accurate and efficient numerical analysis is required to explain both linear and nonlinear physical characteristics. A vector finite element based model was developed to precisely synthesize the guided modes in order to evaluate coupling coefficients, nonlinear coefficient and higher order dispersions of PCFs. This finite element model (FEM) is capable of evaluating coupling length of directional coupler implemented in dual core PCF, which was supported by existing experimental results. We used the parameters extracted from FEM in higher order coupled nonlinear Schrödinger equation (HCNLSE) to model short duration pulses including soliton propagation through the PCF. Split-step Fourier Method (SSFM) was used to solve HCNLSE. Recently, reported experimental work reveals that the dual core PCF behaves like a nonlinear switch and also it initiates continuum generation which could be used as a broadband source for wavelength division multiplexing (WDM). These physical effects could not be explained by the existing analytical formulae such as the one used for the regular fiber. In PCF the electromagnetic wave encounters periodic changes of material that demand a numerical solution in both linear and nonlinear domain for better accuracy. Our numerical approach is capable of explaining switching and some of the spectral features found in the experiment with much higher degree of design freedom. Numerical results can also be used to further guide experiments and theoretical modeling.Ph.D.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering PhD
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De, Vito D. Timothy James. "Modeling aerosol puff concentration distributions from point sources using artificial neural networks". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0030/MQ65852.pdf.
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De, Vito D. Timothy James. "Modeling aerosol puff concentration distributions from point sources using artificial neural networks". Ottawa : National Library of Canada = Bibliothèque nationale du Canada, 2002. http://www.nlc-bnc.ca/obj/s4/f2/dsk1/tape3/PQDD%5F0030/MQ65852.pdf.
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Spicher, Joel. "Volatility Modeling and Straddle Trading". St. Gallen, 2006. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/97327993001/$FILE/97327993001.pdf.
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Vedovoto, João Marcelo. "Mathematical and numerical modeling of turbulent reactive flows using a hybrid LES/PDF methodology". Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2011. http://www.theses.fr/2011ESMA0015.
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Ce travail de thèse est consacré au développement d'une approche numérique permettant de conduire des simulations "low Mach number" d'écoulements réactifs. L'algorithme d'intégration retenu pour procéder à la résolution des équations de transport repose sur une méthode implicite de prédiction-correction (méthode de projection). Une contrainte physique est retenue pour garantir que le champ de vitesse est résolue correctement. Le code de calcul est soumis à plusieurs séries de vérifications préliminaires basées sur l'emploi de la méthode solution manufacturées pour des conditions incompressibles d'abord puis à masse volumique variable qui permettent de statuer quant à la bonne implémentation des schémas numériques retenus. Les performances de l'outil numérique en terme de stabilité et de robustesse sont elles-aussi analysées dans des situations simples : couche de mélange à densité variable en développement spatial et temporel. Le modèle numérique final repose sur l'emploi d'une méthode hybride LES/PDF. Pour ce qui concerne la représentation de la turbulence, deux fermetures sont implémentées pour représenter l'effet des fluctuations de vitesse non résolues. Il s'agit du modèle de Smagorinsky dans sa version dynamique ou non. La spécification de conditions aux limites turbulentes réalistes est elle-aussi analysée en détail et trois approches différentes sont considérées. Pour ce qui concerne la combustion, l'influence des fluctuations de composition aux échelles non résolues est pris en compte par le biais d'une résolution de la PDF scalaire de sous maille. Le modèle de PDF correspondant repose sur l'emploi d'une méthode de Monte Carlo. Des équations différentielles stochastiques, équivalentes aux équations de Fokker-Planck, sont résolues pour la variable de progrès de la réaction chimique. L'objectif final est aussi de pouvoir procéder, à moyen terme, à des simulations LES en géométries complexes et l'emploi du calcul distribué est essentiel. De ce point de vue, la méthode de décomposition de domaine retenue dans ce travail montre des niveau de performances relativement satisfaisants. Les capacités du modèle numérique résultant de ces développements sont illustrées sur deux configurations expérimentales. La première géométrie correspond à un écoulement très fortement turbulent de réactifs pré-mélangés dans un canal bidimensionnel. La seconde correspond à un jet rapide et non confiné de réactifs pré-mélangésThe present work is devoted to the development and implementation of a computational framework to perform numerical simulations of low Mach number turbulent reactive flows. The numerical algorithm designed for solving the transport equations relies on a fully implicit predictor-corrector integration scheme. A physically consistent constraint is retained to ensure that the velocity field is solved correctly, and the numerical solver is extensively verified using the Method of Manufactured Solutions (MMS) in both incompressible and variable-density situations. The final computational model relies on a hybrid Large Eddy Simulation / transported Probability Density Function (LES-PDF) framework. Two different turbulence closures are implemented to represent the residual stresses: the classical and the dynamic Smagorinsky models. The specification of realistic turbulent inflow boundary conditions is also addressed in details, and three distinct methodologies are implemented. The crucial importance of this issue with respect to both inert and reactive high fidelity numerical simulations is unambiguously assessed. The influence of residual sub-grid scale scalar fluctuations on the filtered chemical reaction rate is taken into account within the Lagrangian PDF framework. The corresponding PDF model makes use of a Monte Carlo technique: Stochastic Differential Equations (SDE) equivalent to the Fokker-Planck equations are solved for the progress variable of chemical reactions. With the objective of performing LES of turbulent reactive flows in complex geometries, the use of distributed computing is mandatory, and the retained domain decomposition algorithm displays very satisfactory levels of speed-up and efficiency. Finally, the capabilities of the resulting computational model are illustrated on two distinct experimental test cases: the first is a two-dimensional highly turbulent premixed flame established between two streams of fresh reactants and hot burnt gases which is stabilized in a square cross section channel flow. The second is an unconfined high velocity turbulent jet of premixed reactants stabilized by a large co-flowing stream of burned products
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Farinholt, Kevin. "Modal and Impedance Modeling of a Conical Bore for Control Applications". Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/35560.
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The research presented in this thesis focuses on the use of feedback control for lowering acoustic levels within launch vehicle payload fairings. Due to the predominance of conical geometries within payload fairings, our work focused on the analytical modeling of conical shrouds using modal and impedance based models. Incorporating an actuating boundary condition within a sealed enclosure, resonant frequencies and mode shapes were developed as functions of geometric and mechanical parameters of the enclosure and the actuator. Using a set of modal approximations, a set of matrix equations have been developed describing the homogeneous form of the wave equation. Extending to impedance techniques, the resonant frequencies of the structure were again calculated, providing analytical validation of each model. Expanding this impedance model to first order form, the acoustic model has been coupled with actuator dynamics yielding a complete model of the system relating pressure to control voltage.
Using this coupled state-space model, control design using Linear Quadratic Regulator and Positive Position Feedback techniques has also been presented. Using the properties of LQR analysis, an analytical study into the degree of coupling between actuator and cavity as a function of actuator resonance has been conducted. Constructing an experimetnal test-bed for model validation and control implementation, a small sealed enclosure was built and outfitted with sensors. Placing a control speaker at the small end of the cone the large opening was sealed with a rigid termination. An internal acoustic source was used to excite the system and pressure measurements were captured using an array of microphones located throughout the conic section. Using the parameters of this experimental test-bed, comparisons were made between LQR and PPF control designs. Using an impulse disturbance to excite the system, LQR simulations predicted reductions of 53.2% below those of the PPF design, while the control voltages corresponding to these reductions were 43.8% higher for LQR control.
Actual application of these control designs showed that the ability to manually set PPF gains made this design technique much more convenient for actual implementation. Yielding overall attenuation of 38% with control voltages below 200 mV, single-channel low authority control was seen to be an effective solution for low frequency noise reduction. Control was then expanded to a larger geometry representative of Minotaur fairings. Designing strictly from experimental results, overall reductions of 38.5% were observed. Requiring slightly larger control voltages than those of the conical cavity, peak voltages were still found to be less than 306 mV. Extrapolating to higher excitation levels of 140 dB, overall power requirements for 38.5% pressure reductions were estimated to be less than 16 W.Master of Science
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Haeri, S. "Hierarchical modelling of multiphase flows using fully resolved fixed mesh and PDF approaches". Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/348830/.
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Fully–resolved simulations of multiphase flow phenomena and in particular particulate flow simulations are computationally expensive and are only feasible on massively parallel computer clusters. A 3D SIMPLE type pressure correction algorithm is implemented and extensively tested and parallelized to exploit the power of massively parallel computing clusters currently available. Domain decomposition and communication schemes applicable to a general unstructured or structured multi–block CFD codes are discussed and algorithms are proposed, implemented and tested. Several high–performance linear solvers and a multi–grid strategy for the current framework are implemented and the best types of solvers are identified. A 2D CFD code is developed by the author to test several possible fixed–mesh strategies. Variations of immersed boundary (IB) and fictitious domain (FD) methods are implemented and compared. FD methods are identified to have better properties especially if other transport phenomena are also considered. Therefore an FD method is adapted by the author for the SIMPLE type flow solvers and is extended to heat transfer problems. The method is extensively tested for the simulation of flow around stationary in addition to freely moving particles and forced motion where both natural and forced convection are considered. The method is used to study the flow and heat transfer around a stationary cylinder and a new high resolution correlation is devised for the estimation of the local Nusselt number curves. Free fall problem for a single circular cylinder is considered and the effects of internal heat generation and also long term behavior of single cold particle subject to natural convection are also studied in detail. A particle collision strategy is also adapted and tested for the particle–particle collision problems. The FD algorithm is extended to the 3D framework and the flow around single stationary sphere and also free fall of a single sphere are used to validate the FD algorithm in 3D. A unique polydispersed fluid-particle turbulent modelling process is reviewed and the closure problem for this framework is studied in detail. Two methods for the closure of the non–integer moments which results from the polydispersity of the particles are proposed namely PDF reconstruction using Laguerre polynomials and a unique direct method named Direct Fractional Method of Moments (DFMM). The latter is derived using the results of the fractional calculus by writing an equation for the fractional derivatives of the moment generating function. The proposed methods are tested on a number of problems consisting of analytical, experimental and DNS simulations to asses their validity and viability which shows that both methods provide accurate results with DFMM having more desirable properties.
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Ragozzine, Brett A. "Modeling the Point Spread Function Using Principal Component Analysis". Ohio University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1224684806.
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Di, Veroli Giovanni Yohanan. "Stochastic modelling of particle formation in turbulent flows via transported population balance-PDF method". Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515197.
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Particle formation in turbulent flows arises in a large range of industrial and environmental processes. Examples include the formation of soot particles in combustion engines, the production of nanoparticles via flame synthesis or liquid-phase reactors, or the evolution of aerosol particles in urban/non-urban environments. Simulations' can significantly improve the understanding and design/control of these processes but several difficulties arise when trying to model the underlying physics. These are mainly rooted in both the requirements of appropriate description of the particle's polydispersity and dynamics, as well as of the random fluctuations of the turbulence. In the preliminary part of this work, the turbulent effects on the particle's dynamics are discussed, showing how correlations of various orders appear in the main equation that describes them, the Population Balance Equation (PBE). The thesis elaborates a new approach for the simulation of particle formation in inhomogeneous turbulent flows, the PBE-PDF method, whose concept was recently introduced by [105]. An equation for the joint pdf of the number density and various scalars (such as the chemical species kinetically involved) is derived from fundamental equations that describe the class of considered problems. An algorithm for the numerical solution of the pdf equation is developed, based on Monte Carlo simulations. The method is discussed both at the level of the general concept of the stochastic simulations and at the level of the specific requirements of the PBE-PDF approach. The structure of the implementation is discussed in detail. Starting from empirical or theoretical kinetics, the PBE-PDF is applied to two different turbulent processes involving particle nucleation and growth. The first case considered involves the precipitation of barium sulphate crystals in a tubular reactor, while the second one involves dibutyl phthalate condensation in a free jet. For both cases the method allows for clear analysis and understanding of the particulate phase evolution, emphasis being put on the turbulent effects. Turbulence is found to have significant impact on the overall processes by spatially redistributing the intensity of the particles' mechanisms. Both processes were selected because previously studied experimentally [5][63], which allows the comparison of computed particles' size distribution with measured data. For the crystallization process the simulations' results can be directly compared, showing excellent agreements. Identified uncertainties in the experimental methods are discussed for the aerosol process, even if the computed distributions still show good agreement with the measured ones, particularly for intermediate molar fractions values.
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Baik, Seung Jin [Verfasser], Bernd [Gutachter] Rogg y Viktor [Gutachter] Scherer. "PDF-modeling and simulation of turbulent spray combustion / Seung Jin Baik ; Gutachter: Bernd Rogg, Viktor Scherer". Bochum : Ruhr-Universität Bochum, 2017. http://d-nb.info/1125106255/34.
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Galindo, Lopez Sebastian. "Modelling of Mixed-mode Combustion using Multiple Mapping Conditioning". Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/19646.
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The aim of the present work is to investigate and develop the Multiple Mapping Conditioning (MMC) modelling framework in conjunction with LES into a reliable modelling tool for mixed-mode turbulent combustion. Recent studies show promising results using this approach for diffusion flames and it is important to expand its usability to more complex flame configurations involving finite-rate effects and mixed modes of combustion. In the first part of this thesis fundamental combustion modelling principles are presented followed by the description of the MMC model for turbulent combustion. From this point, this thesis develops a set of computational elements to produce a more general code using object-oriented programming. As a result of these improvements, the implementation of different combustion solvers can be achieved in a fast and intuitive way. In the second part of the work, the different models developed for the specific combustion modes are described and this is followed by the application to two test cases: (i) a set of partially premixed piloted methane jet flames with local extinction and re-ignition, (ii) mixed mode combustion using the Sydney Burner with Inhomogeneous inlets (Flame H and Flame I). Results from these simulations show the requirement to expand and improve the available models in the presence of mixed mode combustion. One of these requirements is density coupling where a new approach is introduced and tested with excellent improvements. A second need, is the introduction of a MMC model to handle premixed flames, to address the challenges of mixed-mode combustion. Here, A recently proposed modified shadow position reference variable for premixed combustion is used and its characteristics are demonstrated in 3D simulations of two Bunsen piloted jet configurations studied in Toronto and in Aachen. The findings of this work suggest that the newly expanded MMC model is an excellent approach to produce improved models able to describe more complex combustion regimes, while keeping simulations tractable.
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Scott, Stephen John. "A PDF based method for modelling polysized particle laden turbulent flows without size-class discretisation". Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434835.
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Bragg, Andrew. "Development of the PDF kinetic approach for modelling inertial particle dispersion in turbulent boundary layers". Thesis, University of Newcastle Upon Tyne, 2012. http://hdl.handle.net/10443/1358.
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This thesis presents developments in the use of probability density function (PDF) kinetic equations to model the dispersion of inertial particles in turbulent boundary layers. The PDF kinetic equation is used as a master equation from which to construct continuum equations for the particle-phase, and these continuum equations form an in nite set of coupled equations which require closure in the particle velocity statistics. Furthermore, the continuum equations contain dispersion tensors which describe the e ect of the underlying uid turbulence on the dispersion of the particles throughout the ow eld. These dispersion tensors themselves require closure and in this thesis new closure models are developed which are non-local and attempt to take into account the e ects of turbulence inhomogeneity, anisotropy and particle-wall collisions on the dispersion tensors. The rst closure model developed is for particles dispersing under Stokes drag forcing only; appropriate for particles whose material density is much greater than that of the uid in which they are dispersed. This closure model is tested against equivalent particle tracking simulation data over a range of particle sizes and the closure model predictions are found to be in excellent agreement. In contrast to the new closure model predictions, the traditional `local' approximations to the dispersion tensors are found to be in signi cant error when compared to the particle tracking data. The closure model is then developed to account for particles dispersing under Stokes drag, added mass and gravitational forcing; added mass forcing being important for particles whose material density is comparable to or less than that of the uid in which they are dispersed. The modelling is presented and a discussion is given regarding the various complex terms that require approximation in this closure model. The closure model predictions are then compared against the alternative local approximations. It is seen that with added mass forcing the local approximations can be qualitatively and quantitatively di erent to the non-local predictions, whereas under only a drag force, errors in the local approximations are mainly quantitative. Finally, consideration is given to the forms of the dispersion tensors appearing in the PDF and continuum equations. It is shown theoretically that the dispersion tensors (and therefore the PDF and continuum equations themselves) are free from the so called `spurious drift' phenomena associated with certain types of models for predicting the dispersion of uid particles in incompressible, inhomogeneous turbulent ows. However, it is also shown that closure approximations applied to the dispersion tensors may result in the introduction of a spurious drift. Nevertheless, it is demonstrated that the arti cial drift introduced by closure approximations does not have any appreciable a ect on the dispersion tensors when they are describing the dispersion of inertial particles.
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Seubert, Niko [Verfasser] y Andreas [Akademischer Betreuer] Kronenburg. "LES-PDF modelling of nucleation and growth of DBP droplets / Niko Seubert ; Betreuer: Andreas Kronenburg". Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2019. http://d-nb.info/1191182614/34.
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Sargent, Aitbala. "Modeling Ice Streams". Fogler Library, University of Maine, 2009. http://www.library.umaine.edu/theses/pdf/SargentA2009.pdf.
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Ribeiro, Jeancarlo. "O PROBLEMA DE DESIGNAÇÃO DE SALAS DE AULA DA PUC GOIÁS". Pontifícia Universidade Católica de Goiás, 2013. http://localhost:8080/tede/handle/tede/2447.
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Previous issue date: 2013-06-17The classroom assignment problem at universities consist in distributing classes scheduled for the appropriate rooms, respecting the requirements in each situation. The objective of this work is to apply the Hungarian algorithm and a computational system to solve the classroom assignment problem time by time. The tests were performed with real data from the PUC Goiás for a quantitative of 5116 classes into 313 classrooms. As a result, we solved the problem in approximately 12 minutes and the solution quality was compared with manual designation usually applied by the institution, which takes a month and a half.
O problema de designação de salas de aula em Universidades consiste em distribuir turmas programadas para as devidas salas, respeitando os requisitos estabelecidos em cada situação. O objetivo deste trabalho é a aplicação do algoritmo húngaro e de um sistema computacional para a resolução do problema de alocação horário por horário. Os testes foram realizados com dados reais da PUC Goiás para um quantitativo de 5116 turmas em 313 salas de aula. Como resultados, resolvemos o problema em aproximadamente 12 minutos e comparamos a qualidade da solução com a designação manual usualmente realizada pela Instituição, a qual leva um mês e meio.
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Bonora, Filippo <1989>. "Numerical modeling for PLF in dairy cattle farms: methods for the analysis of environmental, productive and behavioral parameters". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amsdottorato.unibo.it/8480/1/Bonora_Filippo_tesi.pdf.
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In the last years, marked by considerable social, environmental and economic changes, even the agricultural world has not been exempt from important and continuous transformations, like all aspects of everyday life. In particular, the steady increase of the world population, new eating and life habits, the climate changes and the related and growing attention to the environmental impact are transforming the production and the management of animal husbandry. As already happened in other sectors, the most selected answer at these continuous challenges is the "technological innovation", in this field it is called Precision Livestock Farming (PLF). It is so becoming increasingly common to see in cattle barns, swine and poultry farms cameras, weather stations, collars, pedometers and other unusual sensors and instruments until a few decades ago in these places.
The study carried out in this thesis is part of this scientific�field, particularly with regard to dairy cowshed. The objective of the work is to identify standard methods of analysis aimed at optimizing the management of the herd in terms of welfare and production of individual animals, but also to facilitate the daily work of the farmer.
Two selected case studies were examined in three macro-areas: 1) herd management optimization; 2) relationship between milk production and environmental
conditions; 3) behavioral characteristics of the individual animal. The obtained results underline the importance and usefulness of the devices installed today in the barns and the studies connected to them: if one can manage the enormous amount of data collected through ICT systems and transform it into clear information (for examples graphs), it is possible to create a system capable of optimizing the management of the farm in terms of better quality and greater quantity of product, animal welfare and simplified and more profitable working conditions.Il costante aumento della popolazione mondiale, le nuove abitudini alimentari, e più in generale di vita, da una parte e i cambiamenti climatici e le connesse e crescenti attenzioni verso l'impatto ambientale del proprio lavoro quotidiano dall'altra stanno trasformando la produzione e la gestione delle attività zootecniche di tutto il mondo. Tra le differenti soluzioni che le persone del mestiere stanno scegliendo in risposta a queste continue sfide occupa sicuramente uno dei primi posti il concetto di "innovazione tecnologica", che in questo campo prende il nome di zootecnia di precisione. Diventa quindi sempre più comune vedere telecamere, centraline meteo, collari, pedometri e altri sensori non abituali fino a qualche decennio fa in stalle, porcilaie e allevamenti avicoli. Lo studio effettuato in questa tesi rientra in questo ambito di ricerca, in particolare è incentrato sugli allevamenti di bovine da latte. L'obiettivo del lavoro è stato quello di individuare replicabili metodologie di analisi atte a ottimizzare la gestione della mandria in termini di benessere e di produzione del singolo animale, ma anche al fine di facilitare l'operato quotidiano dell'allevatore. A questo scopo sono stati presi in esame due casi studio appositamente selezionati e sono state progettate e testate sperimentazioni che possono essere racchiuse in tre macro-aree: a) gestione ottimizzata della mandria, b) rapporto produzione - condizioni ambientali e, infine, c) abitudini comportamentali del singolo capo. I risultati ottenuti sottolineano l'importanza e l'utilità dei dispositivi tecnologici installati oggigiorno negli allevamenti e degli studi ad essi connessi. Se infatti si è in grado di gestire l'ingente ammontare di dati acquisiti mediante i dispositivi, e trasformarlo in pure e semplici informazioni, è possibile creare un sistema capace di ottimizzare la gestione dell'intera struttura lavorativa in termini di migliore qualità e maggiore quantità di prodotto, elevato benessere animale e condizioni lavorative semplificate e rese più proficue.
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Jankowski, £ukasz. "Modelling and simulation of light propagation in non-aged and aged step-index polymer optical fibres". Phd thesis, Universität Potsdam, 2004. http://opus.kobv.de/ubp/volltexte/2005/173/.
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Kunststofflichtwellenleiter (POFs) stellen ein verhältnismäßig neues Medium zur optische Datenkommunikation über kurzen Strecken dar. Während ihrer Einsatzdauer unterliegen POFs unterschiedlichen Arten von Umweltbeanspruchungen, hauptsächlich durch hohe Temperatur, hohe Feuchtigkeit und mechanischen Belastungen. Zahlreiche experimentelle Forschungen beschäftigten sich mit der standardisierten Prüfung der Zuverlässigkeit von im Handel erhältlichen Fasern. Jedoch gab es bisher wenig Erfolg bei der Bemühung, zwei grundlegende optische Erscheinungen, Absorption und Streuung, die die Lichtausbreitung in Fasern stark beeinflussen, zu verstehen und praktisch zu modellieren: Diese beiden Effekte beschreiben nicht nur die Qualität neuer Fasern, sondern sie werden auch stark durch die Alterungsprozess beeinflusst.
Der Hauptzweck dieser Doktorarbeit war es, ein praktisch verwendbares und theoretisch gut fundiertes Modell der Lichtausbreitung in nicht gealterten und gealterten POFs zu entwickeln und es durch optische Experimente zu verifizieren. Dabei wurden anwendungsorientierte Aspekte mit theoretischer POF-Modellierung kombiniert. Die Arbeit enthält die erste bekannte Anwendung der Wellenanalyse zur Untersuchung der winkelabhängigen Eigenschaften der Streuung in Lichtwellenleitern.
Für die praktischen Experimente wurden mehrere POF-Proben unterschiedlicher Hersteller künstlich gealtert, indem sie bis 4500 Stunden bei 100 °C gelagert wurden (ohne Feuchtekontrolle). Die Parameter der jeweiligen Simulationen wurden mittels einer systematischen Optimierung an die gemessen optischen Eigenschaften der gealterten Proben angeglichen. Die Resultate deuten an, dass der Übertragungsverlust der gealterten Fasern in den ersten Tagen und Wochen der Alterung am stärksten durch eine wesentliche physikalische Verschlechterung der Kern-Mantel-Grenzfläche verursacht wird. Chemische Effekte des Alterungsprozesses scheinen im Faserkernmaterial zuerst nach einigen Monaten aufzutreten.
This thesis discusses theoretical and practical aspects of modelling of light propagation in non-aged and aged step-index polymer optical fibres (POFs). Special attention has been paid in describing optical characteristics of non-ideal fibres, scattering and attenuation, and in combining application-oriented and theoretical approaches. The precedence has been given to practical issues, but much effort has been also spent on the theoretical analysis of basic mechanisms governing light propagation in cylindrical waveguides.
As a result a practically usable general POF model based on the raytracing approach has been developed and implemented. A systematic numerical optimisation of its parameters has been performed to obtain the best fit between simulated and measured optical characteristics of numerous non-aged and aged fibre samples. The model was verified by providing good agreement, especially for the non-aged fibres. The relations found between aging time and optimal values of model parameters contribute to a better understanding of the aging mechanisms of POFs.
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Hanses, Jonathan y Morten Eriksson. "Modelling and Control of Heat Distribution in a Powder Bed Fusion 3D Printer". Thesis, Linköpings universitet, Reglerteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-159792.
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This thesis report describes how to improve the control of the temperature in a Powder Bed Fusion 3D printer. This is accomplished by first creating a model ofthe thermal system. To create a good model, both black-box and grey-box models of the system are estimated and compared. Based on the best model, different control designs are examined and the results are compared to find the control design yielding the best results. The system being modelled is a multiple input multiple output system with acomplex internal structure. The modelling can be divided into several steps. Firstly, data has to be acquired from the system. Secondly, the data is analysed and processed. Thirdly, models are estimated based on the collected data. Different model structures such as state-space, ARX, ARMAX, Output Error, Box Jenkins and grey-box models are examined and compared to each other. Finally, the different derived models are validated and it turns out the ARMAX model yields the best prediction capabilities. However, when the controllers were tested on the actual system the controllers that are based on the grey-box model yield the best results. The different control designs examined in this work are diagonal PI controllers, decoupled PI controllers, feed forward controllers, IMC controllers and statefeedback controllers. The controllers are all based on the derived models. The controllers are implemented into a code structure capable of communicating with the printers. Here, tests of the performance for the different controllers on the actual system are executed. The results show that a non-linear system can be controlled using linear controllers. However, introducing some fuzzy control elements such as limiting the controllers to only be used within small temperature intervals and using a fixed input outside this interval yield better results. From these results, the best linear controller is a diagonal PI controller tuned from a grey-box model with as many states as there are controllable areas of the powder bed. The improvement is only marginal compared to the original PI controller, reinforcing the conclusion that some non-linear strategies are needed in the controller in order to achieve significant improvements.
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Alarcão, Davi Taveira Alencar. "MELHORIAS PARA O PROBLEMA DE DESIGNAÇÃO DE SALAS DE AULA DA PUC GOIÁS". Pontifícia Universidade Católica de Goiás, 2015. http://localhost:8080/tede/handle/tede/2460.
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Previous issue date: 2015-02-07The classroom assignment problem at universities consist in distributing classes scheduled for the appropriate rooms, respecting the requirements in each situation. The objective of this work is to improve the process of allocation of classroom PUC Goiás. The tests were performed with real data from the PUC Goiás for a quantitative of 5116 classes into 312 classrooms. As a result, we solved the problem in approximately 34 minutes and the solution quality was compared both with manual designation usually applied by the institution, which takes a month and a half, as with the results found in Ribeiro (2012).
O problema de designação de salas de aula em Universidades consiste em distribuir turmas programadas para as devidas salas, respeitando os requisitos estabelecidos em cada situação. O objetivo deste trabalho é o de melhorar o processo de alocação de salas de aula da PUC Goiás. Os testes foram realizados com dados reais da PUC Goiás para um quantitativo de 5116 turmas em 312 salas de aula. Como resultados, resolvemos o problema em aproximadamente 34 minutos e comparamos a qualidade da solução tanto com a designação manual usualmente realizada pela Instituição, a qual leva um mês e meio, quanto com os resultados encontrados em Ribeiro (2012).
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Hari, haran Ramaswam. "Modeling Intersections of Geospatial Lifelines". Fogler Library, University of Maine, 2001. http://www.library.umaine.edu/theses/pdf/HariharanR2001.pdf.
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Oliphant, Alma H. "Numerical Modeling of Friction Stir Welding: A Comparison of Alegra and Forge3". Diss., CLICK HERE for online access, 2004. http://contentdm.lib.byu.edu/ETD/image/etd417.pdf.
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Castro, Bolinaga Celso Francisco. "Hydraulic Modeling of a River Network for Predicting Flood Inundation using HEC-RAS and GIS Models - A Case Study in Southern Virginia". Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/49555.
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A flood inundation study is presented for a watershed located in south central Virginia. A HEC-RAS hydrodynamic model of the main river network was developed to assess the impact of a number of hydrologic events, including the Probable Maximum Flood (PMF), in the area of interest. The primary goal of the study was to transform discharge hydrographs produced by HEC-HMS, an event-based hydrologic model, into water surface elevations and flood inundation spatial extents.Initially, a river terrain model was constructed using data from publically available sources and filed survey campaigns. HEC-GeoRAS and ArcGIS were used to document and integrate the considerable amount of data required for building the model. Then, a calibration process was performed using stage-discharge predictor curves. The HEC-RAS unsteady flow component was employed for routing the discharge hydrographs through the modeled river network. Flood inundation maps, as well as longitudinal water surface elevation and channel velocity profiles were generated for the study reaches.
As part of the flood inundation study, an uncertainty quantification analysis was carried out on the boundary roughness of the floodplains. The objective was to measure the extent to which flood inundated areas, water surface elevations, and channel velocities were influenced by variations on this empirically-based model coefficient.
Finally, the impact of various hydraulic characteristics of the modeled river on the sediment transport process is examined. This characterization is intended to provide a better understanding of a subsequent sediment transport modeling effort to be performed under severe flooding conditions.
Master of Science
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Grandón, Carlos. "Résolution de systèmes de équations de distance avec incertitudes". Phd thesis, Université de Nice Sophia-Antipolis, 2007. http://tel.archives-ouvertes.fr/tel-00328101.
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Nous nous intéressons à une classe particulière de problèmes, les systèmes d´équations de distance avec des incertitudes, qui apparaissent fréquemment en robotique (et dans d´autres domaines). Nous considérons les valeurs entachées d´incertitudes comme des valeurs qui ne sont pas exactement connues mais sont dans des limites bien définies. Ces valeurs sont représentées par des intervalles, et représentent fréquemment les mesures de quantités physiques. Résoudre un problème avec des incertitudes signifie trouver les solutions en considérant les inexactitudes des données, afin d´obtenir des réponses certifiées. Le but est de résoudre des systèmes d´équations de distance avec des incertitudes dans leurs paramètres de la manière la plus précise possible, en combinant différentes techniques d´analyse par intervalles et de programmation par contraintes. Nous proposons un algorithme spécifique de type Branch and Prune combiné avec une bissection conditionnelle qui permet de calculer une approximation grossière des différents continuums de solutions. Le calcul d´une approximation plus précise décrivant chaque continuum a été aussi étudié. Nous montrons que pour calculer cette approximation, il faut considérer un test de boîte intérieure, afin de détecter des parties de l´espace contenant seulement des solutions au problème. L´utilisation d´un tel test réduit la quantité de boîtes produites, et fournit plus d´informations à propos des différentes zones solutions. Nous proposons aussi une stratégie de construction de boîte intérieure basée sur des résultats théoriques sur les intervalles modaux combinés avec une technique de programmation par contraintes appelée projection.
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Kingston, William John III. "Hydrologic Modeling of a Probable Maximum Precipitation Event Using HEC-HMS and GIS Models - A Case Study of Two Watersheds in Southern Virginia-". Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/76812.
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Presented in this thesis is a case study of two study watersheds located in south central Virginia. For each, a HEC-HMS event-based hydrologic model was constructed to simulate the rainfall-runoff response from the Probable Maximum Storm (PMS), the theoretical worst-case meteorological event that is capable of occurring over a particular region. The primary goal of these simulations was to obtain discharge hydrographs associated with the Probable Maximum Flood (PMF) at key locations in each of the watersheds. These hydrographs were subsequently used to develop flood inundation maps of the study areas and to characterize sediment transport phenomena in the study reaches under severe flooding conditions.
To build the hydrologic basin models, ArcHydro, HEC-GeoHMS and ArcGIS were employed to assimilate the substantial amount of input data and to extract the pertinent modeling parameters required for the selected simulation methods. In this, the SCS Loss and Transform Methods, along with the Muskingum Routing Method, were adopted for the HEC-HMS simulations.
Once completed, the basin models were calibrated through a comparison of simulated design storm flows to frequency discharge estimates obtained with regional regression techniques and a flood frequency analysis. The models were then used to simulate their respective PMS events, which were developed following recommendations from the Hydrometeorological Branch of the National Weather Service and the U.S. Army Corps of Engineers.
Descriptions of each of the study sites, explanations of the modeling theory and development methodologies, and discussions of the modeling results are all detailed within.Master of Science
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Wunsch, Dirk. "Theoretical and numerical study of collision and coalescence - Statistical modeling approaches in gas-droplet turbulent flows". Thesis, Toulouse, INPT, 2009. http://www.theses.fr/2009INPT031H/document.
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Ce travail consiste en une étude des phénomènes de coalescence dans un nuage de gouttes, par la simulation numérique directe d'un écoulement turbulent gazeux, couplée avec une approche de suivi Lagrangien pour la phase dispersée. La première étape consiste à développer et valider une méthode de détection des collisions pour une phase polydispersée. Elle est ensuite implémentée dans un code couplé de simulation directe et de suivi Lagrangien existant. Des simulations sont menées pour une turbulence homogène isotrope de la phase continue et pour des phases dispersées en équilibre avec le fluide. L'influence de l'inertie des gouttes et de la turbulence sur le taux de coalescence des gouttes est discutée dans un régime de coalescence permanente. Un aperçu est donné de la prise en compte d'autres régimes de collision et de coalescence entre gouttes. Ces simulations sont la base de développement et de validation des approches utilisées dans les calculs à l'échelle industrielle. En particulier, les résultats des simulations sont comparés avec les prédictions d'une approche Lagrangienne de type Monte-Carlo et de l'approche Eulerienne 'Direct Quadrature Method of Moments' (DQMOM). Différents types de fermeture des termes de coalescence sont validés. Les uns sont basés sur l'hypothèse de chaos-moléculaire, les autres sont capables de prendre en compte des corrélations de vitesses des gouttes avant la collision. Il est montré que cette derniere approche prédit beaucoup mieux le taux de coalescence par comparaison avec les résultats des simulations déterministesCoalescence in a droplet cloud is studied in this work by means of direct numerical simulation of the turbulent gas flow, which is coupled with a Lagrangian tracking of the disperse phase. In a first step, a collision detection algorithm is developed and validated, which can account for a polydisperse phase. This algorithm is then implemented into an existing code for direct numerical simulations coupled with a Lagrangian tracking scheme. Second, simulations are performed for the configuration of homogeneous isotropic turbulence of the fluid phase and a disperse phase in local equilibrium with the fluid. The influence of both droplet inertia and turbulence intensity on the coalescence rate of droplets is discussed in a pure permanent coalescence regime. First results are given, if other droplet collision outcomes than permanent coalescence (i.e. stretching and reflexive separation) are considered. These results show a strong dependence on the droplet inertia via the relative velocity of the colliding droplets at the moment of collision. The performed simulations serve also as reference data base for the development and validation of statistical modeling approaches, which can be used for simulations of industrial problems. In particular, the simulation results are compared to predictions from a Lagrangian Monte-Carlo type approach and the Eulerian 'Direct Quadrature Method of Moments' (DQMOM) approach. Different closures are validated for the coalescence terms in these approaches, which are based either on the assumption of molecular-chaos, or based on a formulation, which allows to account for the correlation of droplet velocities before collision by the fluid turbulence. It is shown that the latter predicts much better the coalescence rates in comparison with results obtained by the performed deterministic simulations
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Zhao, Zhong. "An Integrated Approach to Location Modeling". Fogler Library, University of Maine, 2011. http://www.library.umaine.edu/theses/pdf/ZhaoZ2011.pdf.
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Ramalingam, Chitra. "Modeling Multiple Granularities of Spatial Objects". Fogler Library, University of Maine, 2002. http://www.library.umaine.edu/theses/pdf/RamalingamC2002.pdf.
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Martin, Kevin Braun. "Hydrogen infrastructure: resource evaluation and capacity modeling". Diss., Rolla, Mo. : Missouri University of Science and Technology, 2009. http://scholarsmine.mst.edu/thesis/pdf/Martin_09007dcc8071f0b7.pdf.
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Thesis (Ph. D.)--Missouri University of Science and Technology, 2009.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed December 15, 2009) Includes bibliographical references (p. 72-80).
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Lamb, Patricia Darlene. "Application of the modeling role-modeling theory to mentoring in nursing". Thesis, Montana State University, 2005. http://etd.lib.montana.edu/etd/2005/lamb/LambP0805.pdf.
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Nzokou, Tanekou François. "Ice rupture hydrodynamic modeling". Thesis, Université Laval, 2010. http://www.theses.ulaval.ca/2010/26683/26683.pdf.
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RIZZA, GIOVANNI. "Modelling of the powder sintering process and relative thermal conductivity variation during the electron beam powder bed fusion (PBF-EB)". Doctoral thesis, Politecnico di Torino, 2023. https://hdl.handle.net/11583/2976601.
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Aguenaou, Karim. "Modeling of solidification". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ36950.pdf.
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Shareef, Ali. "Localization and Energy Modeling in Wireless Sensor Networks". Fogler Library, University of Maine, 2008. http://www.library.umaine.edu/theses/pdf/ShareefA2008.pdf.
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King, Joshua P. "Modeling Boundaries of Influence among Positional Uncertainty Fields". Fogler Library, University of Maine, 2002. http://www.library.umaine.edu/theses/pdf/KingJP2002.pdf.
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Zhang, Rui. "Hierarchies for Event-Based Modeling of Geographic Phenomena". Fogler Library, University of Maine, 2005. http://www.library.umaine.edu/theses/pdf/ZhangR2005.pdf.
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Ekman, Torbjörn. "Prediction of mobile radio channels : modeling and design /". Uppsala : Signals and systems [Signaler och system], Univ. [distributör], 2002. http://www.signal.uu.se/Publications/pdf/a023.pdf.
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Zhao, Xiyue. "Modeling and control of freeze-form extrusion fabrication". Diss., Rolla, Mo. : University of Missouri-Rolla, 2007. http://scholarsmine.mst.edu/thesis/pdf/Zhao_09007dcc8043fdb1.pdf.
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Thesis (M.S.)--University of Missouri--Rolla, 2007.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed April 16, 2008) Includes bibliographical references.
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Wegener, Jeffrey Lewis. "Experiments and modeling of shear-driven film separation". Diss., Rolla, Mo. : Missouri University of Science and Technology, 2009. http://scholarsmine.mst.edu/thesis/pdf/Wegener_09007dcc80605416.pdf.
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Thesis (M.S.)--Missouri University of Science and Technology, 2009.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed March 18, 2009) Includes bibliographical references (p. 153-156).
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Sen, Debamoy. "Modeling and simulation of electrochemical magneto hydro dynamics". Diss., Rolla, Mo. : Missouri University of Science and Technology, 2009. http://scholarsmine.mst.edu/thesis/pdf/Sen_09007dcc8069b391.pdf.
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Thesis (M.S.)--Missouri University of Science and Technology, 2009.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed August 10, 2009) Includes bibliographical references (p. 65-67).
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Hemant, Kumar. "Modelling and interpretation of global lithospheric magnetic anomalies". Berlin : GeoForschungsZentrum Potsdam, 2003. http://www.gfz-potsdam.de/bib/pub/str0310/0310.pdf.
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Forde, Cameron E. "Modeling biological iron". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0021/NQ27644.pdf.
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Oroumiyeh, Farzan. "Temporal Interpolation Modeling of Cincinnati’s Central Air Quality Monitoring Data for Use in Epidemiologic Studies: PM2.5 Source Apportionment using Positive Matrix Factorization (PMF)". University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1504800976355814.
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