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1

Sarkisov, Pavel. "Physical understanding of tire transient handling behavior." Cuvillier Verlag, 2018. https://tud.qucosa.de/id/qucosa%3A34414.

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Increasing vehicle performance requirements and virtualization of its development process require more understanding of physical background of tire behavior, especially in transient rolling conditions with combined slip. The focus of this research is physical description of transient generation of tire lateral force and aligning torque. Using acceleration measurement on the tire inner liner it was observed that the contact patch shape of the rolling tire changes nonlinearly with slip angle and becomes asymmetric. Optical measurement outside and inside the tire has clarified that carcass lateral bending features both shear and rotation angle of its cross-sections. A physical simulation model was developed, which considers the observed effects. A special iterative computing algorithm was proposed. The model was qualitatively validated using not only tire force and torque responses, but also deformation of the tire carcass. The model-based analysis explained which tire structural parameters are responsible for which criteria of tire performance. Contact patch shape change had a low impact on lateral force and aligning torque. Variation of carcass bending behavior perceptibly influenced aligning torque generation. As an example, the gained understanding was applied for feasibility analysis of a novel method to estimate the utilized friction potential rate of a rolling tire.:1 Introduction 1.1 Thesis structure 1.2 Motivation 1.3 State of the art 1.4 Mission statement 1.5 Main terms and hypotheses 1.6 Summary of chapter 1 2 Experimental investigation of tire deformation 2.1 Introduction to experimental research 2.2 Test samples 2.3 Experimental equipment 2.4 Contact patch pressure distribution 2.5 Contact patch geometry of the rolling tire 2.6 Tire carcass deformation 2.7 Tread block properties 2.8 Summary of chapter 2 3 Simulation method of tire deformation behavior 3.1 Concept development 3.2 Physical representation of the model 3.3 Model computing method 3.4 Model parameterization routine 3.5 Model validation 3.6 Summary of chapter 3 4 Model-based analysis 4.1 Understanding of the physical background 4.2 An example of application 4.3 Summary of chapter 4 5 Investigation summary and discussion 5.1 Key results 5.2 Discussion, critique and outlook References List of abbreviations List of symbols List of tables List of figures Appendix
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2

Zhou, Xiaobin. "Mathematical and Physical Simulations of BOF Converters." Doctoral thesis, KTH, Tillämpad processmetallurgi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-175462.

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The purpose of this study is to develop mathematical models to explore the mixing and its related phenomena in converter bath. Specifically, first, a mathematical model of a physical model converter, which was scaled down to 1/6th of a 30 t vessel, was developed in this study. A number of parameters were studied and their effects on the mixing time were recorded in a top blown converter. Second, a mathematical model for a combined top-bottom blown was built to investigate the optimization process. Then, a side tuyere was introduced in the combined top-bottom blown converter and its effects on the mixing and wall shear stress were studied. Moreover, based on the above results, the kinetic energy transfer phenomena in a real converter were investigated by applying the mathematical models. A simplified model, in which the calculation region was reduced to save calculation compared to simulations of the whole region of the converter, was used in the mathematical simulation. In addition, this method was also used in the simulation of real converters. This approach makes it possible to simulate the Laval nozzle flow jet and the cavity separately when using different turbulence models. In the top blown converter model, a comparison between the physical model and the mathematical model showed a good relative difference of 2.5% and 6.1% for the cavity depth and radius, respectively. In addition, the predicted mixing time showed a good relative difference of 2.8% in comparison to the experimental data. In an optimization of a combined top-bottom blown converter, a new bottom tuyere scheme with an asymmetrical configuration was found to be one of the best cases with respect to a decreased mixing time in the bath. An industrial investigation showed that the application effects of the new tuyere scheme yield a better stirring condition in the bath compared to the original case. Furthermore, the results indicated that the mixing time for a combined top-bottom-side blown converter was decreased profoundly compared to a conventional combined top-bottom blown converter. It was found that the side wall shear stress is increased by introducing side blowing, especially in the region near the side blowing plume. For a 100 t converter in real, the fundamental aspects of kinetic energy transfer from a top and bottom gas to the bath were explored. The analyses revealed that the energy transfer is less efficient when the top lance height is lowered or the flowrate is increased in the top blowing operations. However, an inverse trend was found. Namely, that the kinetic energy transfer is increased when the bottom flowrate is increased in the current bottom blowing operations. In addition, the slag on top of the bath is found to dissipate 6.6%, 9.4% and 11.2% for the slag masses 5, 9 and 15 t compared to the case without slag on top of the surface of the bath, respectively.<br><p>QC 20151015</p>
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3

Peterson, Eric W. "Tire-Road Friction Coefficient Estimation Using a Multi-scale, Physics-based Model." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/51148.

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The interaction between a tire and road surface is of critical importance as the motion of a car in both transient and steady-state maneuvers is predicated on the friction forces generated at the tire-road interface. A general method for predicting friction coefficients for an arbitrary asphalt pavement surface would be an invaluable engineering tool for designing many vehicle safety and performance features, tire design, and improving asphalt-aggregate mixtures used for pavement surfaces by manipulating texture. General, physics-based methods for predicting friction are incredibly difficult, if not impossible to realize—However, for the specific case of rubber sliding across a rough surface, the primary physical mechanisms responsible for friction, notably rubber hysteresis, can be modeled. The objective of the subsequent research is to investigate one such physics model, referred to as Persson Theory, and implement the constitutive equations into a MatLab® code to be solved numerically. The model uses high-resolution surface measurements, along with some of the physical properties of rubber as inputs and outputs the kinetic friction coefficient. The Persson model was successfully implemented into MatLab® and high resolution measurements (from optical microscopy and imaging software) were obtained for a variety of surfaces. Friction coefficients were calculated for each surface and compared with measured friction values obtained from British Pendulum testing. The accuracy and feasibility of the Persson model are discussed and results are compared with a simpler, semi-empirical indenter model. A brief discussion of the merits and drawbacks of the Persson model are offered along with recommendations for future research based on the information acquired from the present study.<br>Master of Science
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4

Rajapakshe, Madhura Priyanga Nishshanke. "Physically Meaningful Harmonization of Tire/Pavement Friction Measurement Devices." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3303.

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Accurate characterization and evaluation of tire/pavement friction is critical in assuring runway and highway safety. Historically, Pavement Friction Measurement Devices (PFMDs) employing different measuring mechanisms have been used to evaluate tire/pavement friction. They yield significantly disparate friction coefficients under the same contact conditions. Currently, an empirically developed data harmonization method based on a reference device (Dynamic Friction Tester (DFT)) is used in an attempt to overcome the disparities between the measurements using various different PFMDs. However, this method, which has been standardized by the American Society for Testing and Materials (ASTM E1960), has been criticized for its inconsistency by researchers and runway/highway operations personnel. The objective of this dissertation research was to develop a systematic and physically intuitive harmonization method for PFMDs that will improve the comparability of their data. As a foundation for such a harmonization, the LuGre tire model that employs physically meaningful parameters to represent the main attributes of tire/pavement friction was evaluated and validated. Measurements of tire/pavement friction by three widely used PFMDs; Locked Wheel Skid Trailer (LWST), Runway Friction Tester (RFT) and DFT, were accurately predicted using nonlinear optimization of LuGre model parameters. The LuGre model was found to be superior compared to the model used in the current ASTM E1960 standardization procedure for predicting PFMD measurements. A sensitivity analysis was performed to identify the relative significance of the LuGre model parameters in characterizing tire/pavement friction, and to study the effects of variation of those parameters on predicted frictional behavior. A set of laboratory tire experiments was designed and performed to validate the physical significance of LuGre tire model parameters and to study how they behave under typical load, inflation pressure, excitation frequency, and amplitude conditions. An empirical method was developed to accommodate the effects of water film thickness on tire/pavement friction in the LuGre model. The results of the sensitivity analysis and the experiments to directly estimate the model parameters were used to identify and quantify appropriate modifications to the measurement mechanisms of PFMDs that can be introduced to improve the comparability of their results. Friction experiments performed after introducing such modifications to the LWST showed an average reduction of 20% in the deviations between the results of LWST and RFT measurements. The research carried out in this dissertation is significant because it: (i) identified the deficiencies in the current method for harmonizing PFMD measurements and the underlying reasons for these deficiencies, (ii) emphasized the importance of a standardization approach that regulates the physical condition of PFMDs, in order to achieve universal comparability of tire/pavement friction measurements, (iii) validated that the LuGre tire model is a tire/pavement friction model capable of facilitating a better standardization approach, and, (iv) initialized the development of a physically meaningful harmonization procedure for PFMDs.
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5

Faure, Cyril. "Real-time simulation of physical models toward hardware-in-the-loop validation." Thesis, Paris Est, 2011. http://www.theses.fr/2011PEST1020.

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La validation des systèmes Mécatroniques tels que la supervision d'une chaînede traction hybride utilise de plus en plus la simulation Hardware-in-the-Loop. Cela consiste à interconnecter des composants réels du système et des composantssimulés. On parle alors de simulation temps réel car les composants simulés doivent avoir le même comportement temporel que les réels. En d'autres termes, la simulation temps réel d'un modèle nécessite le maillage de l'évolution du temps simulé sur celle du temps réel. Sur les outils existants, l'intégration de modèles physiques représentatifs se heurte à des modèles de calculs et des contraintes temporelles pessimistes. Cette thèse propose des solutions, analytiques ou tirées d'expérimentations au sein d'IFP Energies nouvelles, pour l'implantation adéquate de la simulation temps réel de modèles physiques. Des métriques ont été introduites pourqualifier et quantifier la validité d'une simulation temps réel. Une définition des contraintes temporelles propres à la simulation temps réel a été proposée, accompagnée des règles régissant leur propagation aux calculs sous-jacents. Ces méthodes ont ensuite été déclinées en étude d'ordonnançabilité pour deux systèmes au comportement pseudo périodique : un simulateur de moteur à combustion et un contrôle moteur. Des expérimentations sur la simulation temps réel distribuée d'un moteur, intégrant des modèles phénoménologiques de combustion, ont permis de justifier et de validerles méthodes proposées. Les dégradations dues à la simulation distribuée ont été corrigées par un mécanisme d'extrapolation paramétrable dont le coût d'exécution a été étudié<br>Validation of Mechatronics systems such as hybrid automotive powertrains isincreasingly relying on Harware-in-the-Loop simulation. It consists in interconnecting real components to the real-time simulation of physical models, involving their timely behavior to match their real counterpart. In other words, the evolution of simulated and real time have to be meshed together. Involving representative physical models is currently hindered by both pessimistic models of computation and temporal constraints.This thesis proposes several analytical and experimental answers, carried out at IFP Energies nouvelles, toward the proper implantation of real-time simulation of physical models. Several metrics able to qualify and quantify the success of real-time simulation were proposed, as well as the definition of its dedicated timed constraints, along with the rules for their propagation toward the underlying computations involved.Then, we showed how to take advantage of the pseudo periodic behavior of two systems to reach better schedulability bounds for the real-time simulation of : a combustion engine and an engine control. The methods discussed were then accounted for and validated by several experiments, involving the distributed real-time simulation of an engine including phenomenological combustion models. Also, the perturbations induced by the distributed simulation were addressed by proposing a configurable extrapolation mechanism, taking into account its execution time
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6

Ravi, Aruna Subramanian. "Plasmonic Resonances for Spectroscopy Applications using 3D Finite-Difference Time-Domain Models." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1483634449517314.

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7

Zou, Xiaoming. "Models to measure mobilities by time-of-flight /." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486462702468012.

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8

Pfeifle, Florian Verfasser], and Rolf [Akademischer Betreuer] [Bader. "Physical model real-time auralisation of musical instruments : analysis and synthesis / Florian Pfeifle. Betreuer: Rolf Bader." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2016. http://d-nb.info/1108769462/34.

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9

Nelson, A. D. "Observation-Model Comparisons of Near-Surface Ocean Variability on Interannual, Multidecadal, and Orbital Time Scales." Thesis, University of Colorado at Boulder, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10283702.

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<p> This thesis explores the concepts and techniques of observation-model comparisons of the natural variability of the near-surface ocean on three different time scales. The emphasis on natural variability includes removing the all-time trend and seasonality of the data. All analyses used model outputs of the Community Climate System Model version 3.5 (CCSM3.5). </p><p> The first work, <u>An Ensemble Observing System Simulation Experiment of Global Ocean Heat Content Variability,</u> introduces the use of ensemble of model time series to study how a set of observations and how they are processed can capture the statistics of the system being observed. The technique is applied to global ocean heat content (OHC) down to 700m as observed and processed by the In-Situ Analysis System 2013. This study found that before the implementation of the global Argo program (1990-2005), the observed variability is too significantly biased by the low spatial resolution of the observations to return any meaningful estimates of global OHC variability with a median correlation score of 60% and a signal to noise ratio (SNR) of 1.9. The Argo era (2005-2013) is found to do a much better job at estimating global OHC variability to a median correlation score to 95% and an SNR of 14.7. However, this is only true for annual running means and longer; sub-annual variability is still unreliably resolved. </p><p> The second work, <u>Probability Angular Momenta of Multidecadal Oscillations of the North Atlantic,</u> explores concepts in non-equilibrium statistical mechanics, specifically probability angular momentum, as new tools in observation-model comparisons. The indices analyzed include an index related to the Atlantic Multidecadal Oscillation (AMO) and indices related to other oscillations thought to influence the observed variability in the AMO; the atmospheric North Atlantic Oscillation (NAO), the subsurface-ocean Atlantic Meridional Overturning Circulation (AMOC), and outflow from the Labrador Sea (LSO). The PAM analysis was found to detect cycles of the same magnitude and sign as traditional analyses for the simulated indices; for example, the -NAO leads +AMOC by 2 years, +AMO leads -NAO by 10-20 years, and PAMV leads +AMOC by 2-20 years, although the PAM results typically had too low of confidence to support any conclusions from the observed data. The PAM technique also returned a novel insight; a staistically-significant oscillation in the simulated LSO and AMO on the order of 400-1000 years. Since the model output has a time span of only 720 years, this indicates that the PAM technique may be able to detect modes of oscillation with periods on the order of or longer than the time span of the data analyzed, something that cannot be done to any statistical significance via traditional correlation and spectral techniques. </p><p> The final work, <u>PhaseMap: Comparison of Late Pleistocene Surface Temperature Proxies to an Accelerated CCSM3 Simulation,</u> compares the simulated ocean surface in a CCSM3 model run forced using the last 300,000 years of climate forcings to 50 paleotemperature proxies from deep ocean cores around the world. The accelerated model, which was accelerated 100x to simulate 300,000 years of climate in 3,000 model years, was found to agree poorly with the core proxies. While the core proxies correlate strongly with greenhouse gas, ice volume, and sea level forcings, the model results primarily follow the local insolation. It is unclear from this analysis whether this disagreement results from the model being too sensitive to insolation forcing, not sensitive enough to other forcings, or from the fact that the model's subsurface ocean doesn't respond quickly enough to the accelerated forcings. </p><p> These three different fields of ocean study are also inter-compared to explore their individual strengths and weaknesses, and where the techniques of one field may be useful in another. The modern subsurface ocean observations are plagued with uncertainties, and applying the observing system properties to a model was shown to help interpret the uncertainties associated with the spatio-temporal variability in the number and frequency of observations as well as the methodology used to create global maps from these observations. Paleoceanographers often have to work with proxy data that are unevenly sampled in time, and techniques commonly used to mitigate this issue (e.g. Lomb-Scargle method of periodogram estimation) can be used in modern studies where observational data is not available for short periods of time. </p><p> These works explore and propose techniques and concepts regarding surface and near-surface ocean variability on different temporal scales. They also highlight the importance of establishing connections across disciplines working on these different temporal scales. Together, these results improve our understanding of the role of the ocean on the climate system we depend on, and how different disciplines in ocean science can work together to improve our understanding even further.</p><p>
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10

Moss, Graham James. "A time-dependent collisional-radiative model of low pressure gas discharges." Thesis, University of Sheffield, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269399.

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11

Okonna, Ime Udo. "Time-delayed models of infectious diseases dynamics." Thesis, University of Sussex, 2018. http://sro.sussex.ac.uk/id/eprint/73551/.

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This research work is on time-delayed models of infectious diseases dynamics. The dynamics of infectious diseases are studied in the presence of time delays representing temporary immunity or latency. We have designed and analysed time-delayed models with various parameters to simulate disease dynamics, in a view to gaining insight into the behaviour of a population in the presence of infectious diseases, and the reaction of the population to changes in the management procedure of such infections.
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Chuchacz, Katarzyna. "Real-time hardware implementation and musical interface design for a percussion instrument based on a physical model." Thesis, Queen's University Belfast, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.517292.

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13

Goodale, Benjamin. "Crossfit design maximizing building potential across broad time and modal domains /." Amherst, Mass. : University of Massachusetts Amherst, 2009. http://scholarworks.umass.edu/theses/304/.

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14

Schradin, Leslie J. "Textures, model building, and orbifold gauge anomalies research in three topics in physics beyond the standard model /." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1166571116.

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15

Abdullahi, Yau Muhammad. "Analysis of spatial dynamics and time delays in epidemic models." Thesis, University of Sussex, 2014. http://sro.sussex.ac.uk/id/eprint/49870/.

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Reaction-diffusion systems and delay differential equations have been extensively used over the years to model and study the dynamics of infectious diseases. In this thesis we consider two aspects of disease dynamics: spatial dynamics in a reaction-diffusion epidemic model with nonlinear incidence rate, and a delayed epidemic model with combined effects of latency and temporary immunity. The first part of the thesis is devoted to the analysis of stability and pattern formation in an SIS-type epidemic model with nonlinear incidence rate. By considering the dynamics without spatial component, conditions for local asymptotic stability are obtained for general values of the powers of nonlinearity. We prove positivity, boundedness, invariant principle and permanence of our model. The next generation matrix method is used to derive the corresponding basic reproductive number R0, and the Routh-Hurwitz criterion is used to show that for R0 ≤ 1, the disease-free equilibrium is found to be locally asymptotically stable, for R0 > 1, a unique endemic steady state exists and is found to be locally asymptotically stable. In the presence of diffusion, Turing instability conditions are established in terms of system parameters. Numerical simulations are performed to identify the spatial regions for spots, stripes and labyrinthine patterns in the parameter space. Numerical simulations show that the system has complex and rich dynamics and can exhibit complex patterns, depending on the recovery rate r and the transmission rate β. We have discovered that whenever the transmission rate exceeds the recovery rate the system exhibits stripe patterns which correspond to a disease outbreak, and in the opposite case the system settles on spot patterns which imply the absence of disease outbreaks. Also, we find that increasing the power q can lead to epidemic outbreak even at lower values of the transmission rate β. All numerical simulations use an Implicit-Explicit (IMEX) Euler's method, which computes diffusion terms in Fourier space and reaction terms in the real space. Numerical approximation of the model is benchmarked to prove stability of the numerical scheme, and the method is shown to converge with the correct order. Experimental order of convergence (EOC) and estimates for the error in both L2, H1 and maximum norms have also been computed. Also, we compare our results to those on infectious diseases and our model shows good predictions. In the second part of this thesis, we derive and analyse a delayed SIR model with bilinear incidence rate and two time delays which represent latency Τ1 and temporary immunity Τ2 periods. We prove both local and global stability of the system equilibria in the case when there are no time delays, i.e. both the latency and temporary immunity periods are set to zero. For the case when there is only latency (Τ1 > 1, Τ2 = 0) and the case when the two time delays are identical (Τ1 = Τ2 = Τ ), we show that the endemic steady state is always stable for any parameter values. For the case when there is only temporary immunity (Τ2 > 0, Τ1 = 0) and the case when there are both latency and temporary immunity in the system (Τ1 > 0, Τ2 > 0), we prove the existence of periodic solutions arising from the Hopf bifurcation. The endemic steady state undergoes Hopf bifurcation giving rise to stable periodic solutions. For the last two cases, we show interesting regions of (in)stability of the endemic steady state in the different parameter regimes. We find that by varying the transmission rate β, the natural death rate γ and the disease-induced death rate μ increase the regions of (in)stability. Also, we find that the dynamics of the system is richer when we have the two time delays in the model. Analytical results are supported by extensive numerical simulations, illustrating temporal behaviour of the system in different dynamical regimes. Finally, we relate our results to modelling infectious diseases and our results show good predictions of safety and epidemic outbreak.
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GAMA, ARACHCHIGE NALIN SURANJITH. "PHYSICAL DORMANCY IN SEEDS, WITH SPECIAL REFERENCE TO GERANIACEAE: MORPHO-ANATOMY, DEVELOPMENT, PHYSIOLOGY, BIOMECHANICS AND CLASSIFICATION OF WATER-GAP COMPLEXES." UKnowledge, 2013. http://uknowledge.uky.edu/biology_etds/11.

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The primary aims of this dissertation were to (1) identify and characterize the water-gap complex in seeds of Geraniaceae, (2) investigate its role in physical dormancy (PY) break and (3) develop a new classification system for water-gap complexes in seeds of angiosperms. The winter annuals Geranium carolinianum and G. dissectum were selected as the main representative species for the study, and seeds of an additional 29 species from the Geraniaceae were used to compare the water-gap complex within the family. A new classification system for water-gap complexes in species with PY was developed by comparing the morpho-anatomical features of PY seeds and fruits of 16 families. The water-gap complex of G. carolinianum was identified as a micropyle-hinged valve gap complex, and only a slight morpho-anatomical variation was observed within the family. Ontogenetic studies of the seed coat of G. carolinianum revealed that the water-gap region of Geraniaceae develops as an entity of the micropyle. The timing of seed germination with the onset of autumn can be explained by PY-breaking processes involving (a) two-temperature-dependent steps in G. carolinianum, and (b) one or two moisture-dependent step(s) along with the inability to germinate under high temperatures in G. dissectum. Step-I and step-II in PY-breaking of G. carolinianum are controlled by chemical and physical processes, respectively. This study indicates the feasibility of applying the developed thermal time model to predict or manipulate sensitivity induction in seeds with two-step PY-breaking processes. The model is the first and the most detailed one yet developed for sensitivity induction in PY-break. Based on the morpho-anatomical features, three basic water-gap complexes (types I, II and III) were identified in species with PY in 16 families. Depending on the number of openings involved in initial imbibition, the water-gap complexes were subdivided into simple and compound. The new classification system enables the understanding of relationships between water-gap complexes of taxonomically unrelated species with PY.
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17

Lochau, Malte [Verfasser]. "Model-based Quality Assurance of Cyber-Physical Systems with Variability in Space, over Time and at Runtime / Malte Lochau." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2017. http://d-nb.info/1147968470/34.

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18

Kim, Woopoung. "Development of Measurement-based Time-domain Models and its Application to Wafer Level Packaging." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5012.

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In today's semiconductor-based computer and communication technology, system performance is determined primarily by two factors, namely on-chip and off-chip operating frequency. In this dissertation, time-domain measurement-based methods that enable gigabit data transmission in both the IC and package have been proposed using Time-Domain Reflectometry (TDR) equipment. For the evaluation of the time-domain measurement-based method, a wafer level package test vehicle was designed, fabricated and characterized using the proposed measurement-based methods. Electrical issues associated with gigabit data transmission using the wafer-level package test vehicle were investigated. The test vehicle consisted of two board transmission lines, one silicon transmission line, and solder bumps with 50um diameter and 100um pitch. In this dissertation, 1) the frequency-dependent characteristic impedance and propagation constant of the transmission lines were extracted from TDR measurements. 2) Non-physical RLGC models for transmission lines were developed from the transient behavior for the simulation of the extracted characteristic impedance and propagation constant. 3) the solder bumps with 50um diameter and 100um pitch were analytically modeled. Then, the effect of the assembled wafer-level package, silicon substrate and board material, and material interfaces on gigabit data transmission were discussed using the wafer-level package test vehicle. Finally, design recommendations for the wafer-level package on integrated board were proposed for gigabit data transmission in both the IC and package.
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19

Earl, Joseph Stewart. "A model of time dependence and mechanisms of magnetisation reversal in magneto-optic media." Thesis, Keele University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245878.

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Mumm, Hans Pieter. "A test of time reversal violation in neutron beta decay /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/9802.

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Wheatcroft, Justin C. "Terahertz time domain spectroscopy and Fresnel coefficient based predictive model." Wright State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=wright1347483587.

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22

Verma, Poonam Santosh. "Non-equilibrium surface growth for competitive growth models and applications to conservative parallel discrete event simulations." Diss., Mississippi State : Mississippi State University, 2007. http://library.msstate.edu/etd/show.asp?etd=etd-11092007-141815.

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23

Falkenby, Jesper Hansson. "Physically-based fluid-particle system using DirectCompute for use in real-time games." Thesis, Blekinge Tekniska Högskola, Institutionen för kreativa teknologier, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5560.

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Context: Fluid-particle systems are seldom used in games, the apparent performance costs of simulating a fluid-particle system discourages the developer to implement a system of such. The processing power delivered by a modern GPU enables the developer to implement complex particle systems such as fluid-particle systems. Writing efficient fluid-particle systems is the key when striving for real-time fluid-particle simulations with good scalability. Objectives: This thesis ultimately tries to provide the reader with a well-performing and scalable fluid-particle system simulated in real-time using a great number of particles. The fluid-particle system implements two different fluid physics models for diversity and comparison purposes. The fluid-particle system will then be measured for each fluid physics model and provide results to educate the reader on how well the performance of a fluid-particle system might scale with the increase of active particles in the simulation. Finally, a performance comparison of the particle scalability is made by completely excluding the fluid physics calculations and simulate the particles using only gravity as an affecting force to be able to demonstrate how taxing the fluid physics calculations are on the GPU. Methods: The fluid-particle system has been run using different simulation scenarios, where each scenario is defined by the amount of particles being active and the dimensions of our fluid-particle simulation space. The performance results from each scenario has then been saved and put into a collection of results for a given simulation space. Results: The results presented demonstrate how well the fluid-particle system actually scales being run on a modern GPU. The system reached over a million particles while still running at an acceptable frame rate, for both of the fluid physics models. The results also shows that the performance is greatly reduced by simulating the particle system as a fluid-particle one, instead of only running it with gravity applied. Conclusions: With the results presented, we are able to conclude that fluid-particle systems scale well with the number of particles being active, while being run on a modern GPU. There are many optimizations to be done to be able to achieve a well-performing fluid-particle system, when developing fluid-particle system you should be wary of the many performance pitfalls that comes with it.<br>Vätskebaserade partikelsystem används sällan inom realtidsspel. Dessa system är väldigt prestandakrävande, till den grad att de avskräcker utvecklare från att implementera dem i sina realtidsspel. GPGPU ger utvecklare möjligheten att implementera komplexa partikelsystem, såsom vätskepartikelsystem, och simulera dessa system i realtid. Den här uppsatsen utforskar två olika fysikmodeller som kan användas för vätskesimulering, och sedan utförs det prestandamätningar under varierande omständigheter. Baserat på dessa prestandamätningar så kan slutsatser dras om hur skalbart ett vätskepartikelsystem är, alltså hur prestandan sjunker i förhållande till antalet partiklar i systemet. Slutsatser som dras efter att samtliga mätningar har utförts är att dessa system har en god skalbarhet, men att det finns många prestandafallgropar man måste se upp för när man utvecklar ett vätskepartikelsystem.
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Gargiulo, Irene. "Assessing leisure time physical activity (ltpa) experience in urban. Stream corridors: a baseline for inclusive ltpa promotion." Doctoral thesis, Universitat Internacional de Catalunya, 2020. http://hdl.handle.net/10803/670037.

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Leisure-Time Physical Activity (LTPA) in urban stream corridors is of paramount importance for health and wellbeing promotion among urban dwellers. LTPA experience, namely how (what, with whom, when and where) and why LTPA is practised in particular places, is influenced by various social and physical environmental factors which the stream users may perceive differently. Therefore, an improved understanding of how stream users perceive environmental factors may provide relevant insights and inform on strategies intended to support inclusive LTPA promotion. To this end, combining ecological models with a qualitative Geographic Information System (qGIS) methodology is valuable. The ecological models provide a comprehensive theoretical framework which helps understand the environmental factors that influence LTPA, whilst the qualitative research methods serve to reveal any hidden meanings related to individual experiences behind factors. The collected data combined with GIS, enable the exploration of subjective perceptions of the environment with reference to its spatial dimension. Therefore, this study assessed users’ perceptions of the environmental factors that influence LTPA experiences in the Caldes Stream corridor, in the Metropolitan Region of Barcelona. Accordingly, a sequential mixed methodology based on qualitative ecological approach integrated with GIS was developed in two phases. First, in-depth map-based and go-along interviews allowed for: 1) the categorization of the different types of stream users according to their characteristics and motivations for LTPA, 2) the identification of the social and physical environmental factors influencing LTPA, 3) the assessment of factors as either barriers or facilitators to LTPA for each type of stream user according to their perceptions (Paper 1). Secondly, given that the safety issue emerged as a key factor influencing women LTPA in the Caldes Stream corridor, the analysis of the relationship between environmental factors and women’s perceptions of safety was undertaken. In-depth interviews with women were further analysed for: 4) the identification of the environmental factors related to women’s perceptions of safety in the stream corridor, and 5) the design of a safety map able to represent both the women’s general and individual perceptions of safety. For the creation of this analytical tool environmental factors were translated into spatial indicators, women’s perceptions were geo-located, and the resultant data was integrated into qGIS (Paper 2). Findings of the present study provided a greater understanding of the different ways in which different users interpret and interact with urban stream corridors when practising LTPA. Specifically, different types of users perceived environmental factors influencing LTPA as either barriers or facilitators contradictorily or coincidentally depending on their motivations for LTPA and their gender. The major conflicts related to divergent perceptions between genders depended on perceptions of safety (Paper 1). Perceptions of safety among women were related to environmental factors, yet they were mediated by women’s socio-cultural background and everyday practices. Against this backdrop, the safety map based on a qualitative GIS approach designed for this study, allowed the assessment of the macro-scale spatial indicators of the environmental factors and the micro-scale of women’s narratives on perceptions of safety from an integrated perspective. The macro-scale perspective provided a general explanation for the phenomenon and helped visualise conflicting domains of interventions. The micro-scale produced deeper and detailed insights into the perception of safety by comparing the big picture with women’s narratives (Paper 2). These findings suggest that 1) the characterisation of types of users according to their motivations for practicing LTPA in green environments and 2) their gender perspective should be at the forefront of inclusive LTPA promotion strategies. At this regard, qGIS analytical tools aimed at identifying the particular needs of the specific types of users could support the customisation of interventions by providing knowledge on the tangible and intangible dimensions associated to the different LTPA experiences. Basing on this knowledge, LTPA promotion policies should combine the provision of physical infrastructure suitable for the different types of users, and long-term educational programs addressed to overcome the limiting effects of certain socio-cultural backgrounds. This research has shown that the thorough understanding of the users’ LTPA experience in urban stream corridors provides significant knowledge to inform policies for inclusive LTPA promotion, thus mitigating the risk of health inequalities among different types of stream users.
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Piryatinska, Alexandra. "Inference for the Levy models and their application in medicine and statistical physics." Case Western Reserve University School of Graduate Studies / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=case1100206169.

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Challa, Jagannadha Reddy. "Electronic and Vibrational Dynamics of Heme Model Compounds-An Ultrafast Spectroscopic Study." Case Western Reserve University School of Graduate Studies / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=case1181323422.

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27

Schafer, Kenneth Joseph. "The development of time-dependent mean-field theory for ion-metal interactions." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184786.

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The development of time-dependent mean-field theory (TDMF) for the treatment of ion-metal interactions is detailed. By allowing for the time-dependent, nonlinear response of the conduction electrons, TDMF provides a self-consistent description that is free of the adiabatic and linear response approximations that have conventionally been used to treat dynamical processes in simple metals. We present the first results of three-dimensional simulations of a bare proton passing through a thin metallic foil. The nonlinear-induced electron density, dynamical screening potential, and electronic stopping power are all displayed as functions of time for several proton velocities ranging from one-half to eight times the Fermi velocity of a simple metal (sodium). We find that a sizable induced density forms behind the proton and that this density is carried along in the wake of the proton with very little dispersion as it traverses the foil. At proton velocities comparable to or above the Fermi velocity, these wake-riding electrons are shaken off as the proton passes through the rear surface of the foil. We find no evidence that the proton forms a stable hydrogen atom as it traverses the foil. At the velocities studied, the conduction electrons provide a weak, asymmetric screening of the proton, with some regions behind the proton actually being overscreened at the higher velocities. A comparison of our results with a standard linear response treatment of the problem reveals both qualitative and quantitative differences in the calculated time-dependent electron density and screening length. We find that the basic assumption underlying the linear response approximation is not justified in this case, due to the strongly nonlinear nature of the conduction electrons' response. These results are illustrative of the kinds of calculations that can be carried out with the simulation package that we have developed and we describe several applications that are planned for the near future. Several innovations in numerical technique, developed in the course of this work, are also detailed.
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Andrean, Stefio Yosse. "Search for Stop Using the ATLAS Detector and Performance Analysis of the Tile Calorimeter with Muons from W Decays." Licentiate thesis, Stockholms universitet, Fysikum, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-191555.

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This thesis presents a search for the supersymmetric partner of the top quark in the final state with one lepton. The search focuses especially in the region of the parameter space where the 2-body decay dominates. The analysis is performed using LHC full Run 2 data at √s = 13 TeV as recorded by the ATLAS detector. No significant excess above the backgrounds is observed, and 95% confidence level exclusion limits are calculated in the stop-neutralino mass plane. Stops are excluded up to 1200 GeV in the low neutralino mass scenario of below 400 GeV. The Tile Calorimeter is part of the ATLAS calorimeter system whose main task is to measure the energy of hadrons. A performance study is conducted on the Tile Calorimeter using muons from W boson decay originating from proton-proton collisions. Each calorimeter cell response is measure in data and compared with detector simulation.  The azimuthal cell response uniformity is also investigated using a likelihood method. Overall, a good data to detector simulation agreement and azimuthal uniformity is observed which shows well-calibrated cells and uniform responses among the calorimeter modules.
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Carias, Rui Manuel Roteiro. "A mathematical model to determine strategic options for a firm using time based financial accounting and physics equations." Thesis, University of South Africa, 2007. http://hdl.handle.net/10500/55.

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Executive Summary This report uses modified physics and the basic business relationship equations to describe the business system. The physics - business equations are derived using conformal mapping, while thermodynamic and kinematic relationships are further developed and related before being applied to a business situation. The system developed has general applicability to business and can be used for strategic competitive positioning, amongst other postulated uses. The main purpose of this project is to build on existing work in the area of process modeling and strategy formulation to define a quantitative management tool that will effectively enable the formulation of a generic framework, to measure the effects of various strategic options using time based financial management and physics models. The main aims of this research project are to provide an evaluative summary of the existing literature on the applications of process modeling and physics to business limited in scope to competitive strategic planning through a literature review of existing business models and the subsequent development of a mathematical model based on kinematics and thermodynamics for strategic formulation. From the literature review derive a mathematical framework relating business and physics based on an indirect relationship of physical laws to business models based on existing knowledge. Further explain why the derived model has applications to business, and derive a non-rigorous mathematical proof thereof. From these equations make recommendations on how this model can be utilised as a tool to assist in strategy formulation. Thereafter provide statistical proof that the model is applicable to a defined set of companies and show by means of applications how to determine optimal strategies using the model. The main objectives of the research project are to utilise the quantitative tool to determine where a company is, and where it should position itself in future to optimise its competitive position. Further, the framework must be developed into a strategic tool that would allow for the fast turnaround in the implementation of strategy, and the ability to quickly predict necessary changes in direction. The statistical hypothesis tested asks if it is possible to relate the laws of physics to business and use the resultant mathematical framework to analyse a firm’s competitive position in an industry and position it accordingly. From the derived equations a mathematical model to determine strategic options for a firm using time based financial accounting principles and physics equations can be formulated and used to find profitable options for a firm. By implication the model can be applied to strategic positioning of the firm. Unfortunately there is no work in the literature reviews to build this study on and much of it is built from first principles. This leads to complex mathematical relationships, which may prove difficult to follow. .
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Zhi, Qiu. "Study of Ionizaton of Quantum Systems with Delta Potentials in Damped and Undamped Time Periodic Fields." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1250019795.

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31

Svensson, Elin. "Physical modelling of acoustic shallow-water communication channels." Doctoral thesis, Stockholm : Farkost och flyg, Kungliga Tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4572.

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32

Walters, Joseph D. "Optimization and Thermodynamic Performance Measures of a Class of Finite Time Thermodynamic Cycles." PDXScholar, 1990. https://pdxscholar.library.pdx.edu/open_access_etds/1186.

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Modifications to the quasistatic Carnot cycle are developed in order to formulate improved theoretical bounds on the thermal efficiency of certain refrigeration cycles that produce finite cooling power. The modified refrigeration cycle is based on the idealized endoreversible finite time cycle. Two of the four cycle branches are reversible adiabats, and the other two are the high and low temperature branches along which finite heat fluxes couple the refrigeration cycle with external heat reservoirs. This finite time model has been used to obtain the following results: First, the performance of a finite time Carnot refrigeration cycle (FTCRC) is examined. In the special case of equal heat transfer coefficients along heat transfer branches, it is found that by optimizing the FTCRC to maximize thermal efficiency and then evaluating the efficiency at peak cooling power, a new bound on the thermal efficiency of certain refrigeration cycles is given by $\epsilon\sb{m} = (\tilde\tau\sp2\sb{m}\ (T\sb{H}/T\sb{L}) - 1)\sp{-1},$ where $T\sb{H}$ and $T\sb{L}$ are the absolute high and low temperatures of the heat reservoirs, respectively, and $\tilde\tau\sb{m}=\sqrt{2}$ + 1 $\simeq$ 2.41 is the dimensionless cycle period at maximum cooling power. Second, a finite time refrigeration cycle (FTRC) is optimized to obtain four distinct optimal cycling modes that maximize efficiency and cooling power, and minimize power consumption and irreversible entropy production. It is found that to first order in cycling frequency and in the special symmetric case, the maximum efficiency and minimum irreversible entropy production modes are equally efficient. Additionally, simple analytic expressions are obtained for efficiencies at maximum cooling power within each optimal mode. Under certain limiting conditions the bounding efficiency at maximum cooling power shown above is obtained. Third, the problem of imperfect heat switches linking the working fluid of an FTRC to external heat reservoirs is studied. The maximum efficiency cycling mode is obtained by numerically optimizing the FTRC. Two distinct optimum cycling conditions exist: (1) operation at the global maximum in efficiency, and (2) operation at the frequency of maximum cooling power. The efficiency evaluated at maximum cooling power, and the global maximum efficiency may provide improved bench-mark bounds on thermal efficiencies of certain real irreversible refrigeration cycles.
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洪觀宇 and Roy Hung. "Time domain analysis and synthesis of cello tones based on perceptual quality and playing gestures." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31215348.

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Lau, Wai-ping, and 劉偉平. "Minimising the calculation time of the cluster program by choosing theminimum convergent cluster size and the best relaxation factor." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B29760392.

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35

Kotchoubey, Jurij. "POLCA-T Neutron Kinetics Model Benchmarking." Thesis, KTH, Reaktorteknologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-176096.

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The demand for computational tools that are capable to reliably predict the behavior of a nuclear reactor core in a variety of static and dynamic conditions does inevitably require a proper qualification of these tools for the intended purposes. One of the qualification methods is the verification of the code in question. Hereby, the correct implementation of the applied model as well as its flawless implementation in the code are scrutinized. The present work concerns with benchmarking as a substantial part of the verification of the three-dimensional, multigroup neutron kinetics model employed in the transient code POLCA-T. The benchmarking is done by solving some specified and widely used space-time kinetics benchmark problems and comparing the results to those of other, established and well-proven spatial kinetics codes. It is shown that the obtained results are accurate and consistent with corresponding solutions of other codes. In addition, a sensitivity analysis is carried out with the objective to study the sensitivity of the POLCA-T neutronics to variations in different numerical options. It is demonstrated that the model is numerically stable and provide reproducible results for a wide range of various numerical settings. Thus, the model is shown to be rather insensitive to significant variations in input, for example. The other consequence of this analysis is that, depending on the treated transient, the computing costs can be reduced by, for instance, employing larger time-steps during the time-integration process or using a reduced number of iterations. Based on the outcome of this study, one can finally conclude that the POLCA-T neutron kinetics is modeled and implemented correctly and thus, the model is fully capable to perform the assigned tasks.
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36

Chanouian, Serg. "What If We Tilt the AOD? : Developing a numerical and physical model of a downscaled AOD converter to investigate flow behaviour when applying an inclination." Thesis, KTH, Materialvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254912.

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In a scrap based stainless steel plant the dominant process for carbon reduction is the Argon oxygen decarburisation process (AOD). The process goes through three steps: decarburisation, reduction and desulphurisation where the main challenge is to oxidise carbon to CO without oxidising the expensive chromium. The general practical approach is to inject a mixture of oxygen and an inert gas, like argon or nitrogen, through tuyeres at the converter side starting with a high amount of oxygen gas which followingly is reduced as the inert gas is increased during the decarburisation steps. This allows for a decrease in partial pressure for the CO bubbles which is thermodynamically favourable for carbon oxidation. Recent studies have shown that an aged AOD converter with a worn lining can decarburise the melt faster than a fresh vessel due to favourable thermodynamic conditions occurring since the bath height is lower in the aged converter. The studies show 8-10% savings of oxygen gas which have led to an interest to study the matter. One of two approaches are taken in the present work with the focus to develop a numerical model that simulates a downscaled AOD converter with applied inclinations that is to be validated through physical modelling. A 75-ton industrial converter was downscaled for water-air experiments where three inclination angles namely 0, 5.5 and 14° were studied with focus on mixing time and penetration length. The physical model was replicated for computational fluid dynamics (CFD) modelling using the Euler-Euler approach in ANSYS Fluent. The models show rather good similarities when comparing gas penetration length, flow structure and mixing time however needs some complementary work and final adjustments before upscaling as well as coupling with thermodynamic modelling can be done.<br>Den dominerande processen för kolfärskning vid skrot baserad rostfri ståltillverkning är AOD- processen (Argon Oxygen Decarburisation). Processen går igenom tre steg, kolfärskning, reducering av krom och svavelrening där de största utmaningarna ligger i att oxidera kol utan att oxidera krom. I praktiken gör detta genom att injicera en blandning av argon och syrgas från sidan av AOD-konvertern för att sänka partial trycket av den kolmonoxid som bildas när kol oxideras. Syftet är att göra det mer termodynamiskt fördelaktigt att oxidera kol i systemet. Den injicerade blandgasen har olika förhållanden under kolfärskning med en hög andel syrgas i början som sedan sänks genom processen tills bara argon injiceras. Tidigare studier har visat att kolfärskningen är en funktion av konverterns ålder där ju äldre en konverter är desto snabbare går kolfärskning. Enligt studierna har det visats att 8-10% mindre syrgas eller användning av reducerings medel kan uppnås i en gammal konverter vilket har väckt ett intresse för vidare studier. I detta arbete har en av två metoder prövats för att undersöka om man kan applicera det som sker i en gammal konverter till en ny. En numerisk modell av en nerskalad AOD-konverter har utvecklats och validerats mot en vattenmodell då konvertern vinklas. En 75-tons konverter nerskalades till en vattenmodell där vinklarna 0, 5.5 och 14° studerades med fokus på blandningstid och penetrations djup. Vattenmodellen gjordes om till en numerisk modell som använde Euler-Euler metoden i ANSYS Fluent. Modellerna visade likheter gällande penetrationsdjup, flödes struktur och blandnings tid men kräver en del justeringar innan en uppskalning samt koppling till termodynamisk modellering kan ske.
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Maurer, Simon. "Analysis and coordination of mixed-criticality cyber-physical systems." Thesis, University of Hertfordshire, 2018. http://hdl.handle.net/2299/21094.

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A Cyber-physical System (CPS) can be described as a network of interlinked, concurrent computational components that interact with the physical world. Such a system is usually of reactive nature and must satisfy strict timing requirements to guarantee a correct behaviour. The components can be of mixed-criticality which implies different progress models and communication models, depending whether the focus of a component lies on predictability or resource efficiency. In this dissertation I present a novel approach that bridges the gap between stream processing models and Labelled Transition Systems (LTSs). The former offer powerful tools to describe concurrent systems of, usually simple, components while the latter allow to describe complex, reactive, components and their mutual interaction. In order to achieve the bridge between the two domains I introduce the novel LTS Synchronous Interface Automaton (SIA) that allows to model the interaction protocol of a process via its interface and to incrementally compose simple processes into more complex ones while preserving the system properties. Exploiting these properties I introduce an analysis to identify permanent blocking situations in a network of composed processes. SIAs are wrapped by the novel component-based coordination model Process Network with Synchronous Communication (PNSC) that allows to describe a network of concurrent processes where multiple communication models and the co-existence and interaction of heterogeneous processes is supported due to well defined interfaces. The work presented in this dissertation follows a holistic approach which spans from the theory of the underlying model to an instantiation of the model as a novel coordination language, called Streamix. The language uses network operators to compose networks of concurrent processes in a structured and hierarchical way. The work is validated by a prototype implementation of a compiler and a Run-time System (RTS) that allows to compile a Streamix program and execute it on a platform with support for ISO C, POSIX threads, and a Linux operating system.
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38

Leube, Philipp Christoph [Verfasser], and Wolfgang [Akademischer Betreuer] Nowak. "Methods for physically-based model reduction in time : analysis, comparison of methods and application / Philipp Christoph Leube. Betreuer: Wolfgang Nowak." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2013. http://d-nb.info/104585946X/34.

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39

Subramanium, Mahesh. "A Study of the Gradient Drift Instability in the High-Latitude Ionosphere Using the Utah State University Time Dependent Ionospheric Model." DigitalCommons@USU, 1996. https://digitalcommons.usu.edu/etd/4869.

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Research over the years has established that the Gradient Drift Instability process causes small-scale irregularities, mostly along the edges of the high-latitude polar cap patches. Studying these irregularities will help in the development of a global Scale Ionospheric model, which is a central part of a global space weather forecast system. Much theoretical work has been done with varying degrees of complexity to study this instability in the high latitude patches. In this work we have used the Utah State University Time Dependent Ionospheric Model to model the high-latitude patches, calculate the growth rate of the instability, and perform a macro-scale study of the phenomenon. This is the first time that real ionospheric values have been used to calculate the growth rate and to provide two-dimensional maps identifying Gradient Drift Instability-caused irregularity regions in the polar cap. Our research shows that regions of intense instability occur along the edges of the tongue of ionization and its throat regions with strong rates along the borders of the cusp region.
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40

Arik, Enis. "Dielectric Properties Of Fuel Oils And Their Ethanol Mixtures Investigated By Terahertz Time-domain Spectroscopy." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615463/index.pdf.

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The purpose of this study is to investigate the dielectric properties of fuel oils and their ethanol mixtures in the THz spectral region. We presented frequency dependent absorption coefficients, refractive indices, and dielectric constants calculated from the measurements of pure and mixtures of fuel oils. As the mixing ratio changes, meaningful shifts were observed in refractive index and absorption coefficient of the mixtures. For pure liquids, we used Debye model which provides a good estimate for the dielectric parameters of pure liquids in microwave region and also in the THz region. Bruggeman model, which is used for describing the interaction between liquids in binary mixtures, did not work for ethanol mixtures of gasoline within our assumptions. However, these mixtures were modeled successfully with a modified Debye model in which the mixture behavior was described with a basic contribution approach. The results suggest that there is no strong interaction between the ethanol and the molecules in the gasoline. We concluded that this new approach offers a simple and useful method to determine the concentration of ethanol in gasoline with 3% (by volume) maximum error.
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41

Gupta, Swati. "Time Dependent Radiation Spectra From Jets of Microquasars." Ohio University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1177353122.

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42

Mu, Xiaoyu. "Ruin probabilities with dependent forces of interest." [Johnson City, Tenn. : East Tennessee State University], 2003. https://dc.etsu.edu/etd/796.

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Thesis (M.S.)--East Tennessee State University, 2003.<br>Title from electronic submission form. ETSU ETD database URN: etd-0713103-233105. Includes bibliographical references. Also available via Internet at the UMI web site.
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Hust, Friedrich [Verfasser], Dirk Uwe [Akademischer Betreuer] Sauer, and Gerd [Akademischer Betreuer] Ascheid. "Physico-chemically motivated parameterization and modelling of real-time capable lithium-ion battery models : a case study on the Tesla Model S battery / Friedrich Emanuel Hust ; Dirk Uwe Sauer, Gerd Ascheid." Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/118734687X/34.

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44

Brown, Mary Jane. "Application of the ARCS Model for designing and developing a motivational intervention for improving diet, physical activity and weight management in first-time mothers during pregnancy." Thesis, Ulster University, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627736.

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Maternal overweight and obesity is associated with adverse pregnancy outcomes. Both women and healthcare professionals have expressed a desire for resources to adequately support pregnant women in successful weight management. The primary aim of this research was to identify any motivational deficits for healthy diet and physical activity behaviours in first-time mothers receiving routine antenatal education and in response develop an intervention that solved these deficits, therefore improving optimal weight gain during pregnancy. Application of the ARCS Model of Motivational Instructional Design (Keller, 1987) was undertaken using a mixed method approach with six interrelated phases: Phase one: Goal setting interventions for improving weight management during pregnancy were identified through a systematic literature review. Phase two: A motivational analysis of current antenatal instruction through non-participant observation. Phase three: Maternal motivation to eat a healthy diet and exercise was explored through one-to-one telephone interviews (n=9) and a theoretical measurement tool was developed and validated in a convenience sample (n= 196) of first-time mothers Phase four: Evidence generated in phases 1-3 was collated to create an overall audience motivational profile where lack of confidence-building instruction was identified as the key motivational problem. Phase five: Motivational objectives were established and appropriate ARCS model strategies selected to solve motivational deficits. Phase six: A new resource: "Yummy Tummies" was created and evaluated positively by maternity staff and women (n=11).
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Sarkar, Sanket. "Extending the Time Scale in Atomistic Simulations: The Diffusive Molecular Dynamics Method." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1321282489.

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46

Staub, David. "Time dependent cone-beam CT reconstruction via a motion model optimized with forward iterative projection matching." VCU Scholars Compass, 2013. http://scholarscompass.vcu.edu/etd/3092.

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The purpose of this work is to present the development and validation of a novel method for reconstructing time-dependent, or 4D, cone-beam CT (4DCBCT) images. 4DCBCT can have a variety of applications in the radiotherapy of moving targets, such as lung tumors, including treatment planning, dose verification, and real time treatment adaptation. However, in its current incarnation it suffers from poor reconstruction quality and limited temporal resolution that may restrict its efficacy. Our algorithm remedies these issues by deforming a previously acquired high quality reference fan-beam CT (FBCT) to match the projection data in the 4DCBCT data-set, essentially creating a 3D animation of the moving patient anatomy. This approach combines the high image quality of the FBCT with the fine temporal resolution of the raw 4DCBCT projection data-set. Deformation of the reference CT is accomplished via a patient specific motion model. The motion model is constrained spatially using eigenvectors generated by a principal component analysis (PCA) of patient motion data, and is regularized in time using parametric functions of a patient breathing surrogate recorded simultaneously with 4DCBCT acquisition. The parametric motion model is constrained using forward iterative projection matching (FIPM), a scheme which iteratively alters model parameters until digitally reconstructed radiographs (DRRs) cast through the deforming CT optimally match the projections in the raw 4DCBCT data-set. We term our method FIPM-PCA 4DCBCT. In developing our algorithm we proceed through three stages of development. In the first, we establish the mathematical groundwork for the algorithm and perform proof of concept testing on simulated data. In the second, we tune the algorithm for real world use; specifically we improve our DRR algorithm to achieve maximal realism by incorporating physical principles of image formation combined with empirical measurements of system properties. In the third stage we test our algorithm on actual patient data and evaluate its performance against gold standard and ground truth data-sets. In this phase we use our method to track the motion of an implanted fiducial marker and observe agreement with our gold standard data that is typically within a millimeter.
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Kincheloe, Lauren M. "College: A Time to Increase Knowledge and Attenuate Health? A Study into College's Influences on Students' Alcohol Consumption, Physical Activity, and Diet." Miami University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=miami1339431346.

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48

Wang, Guang Chao. "Modeling Waves in A Human Brain by Space-Time Conservation Element and Solution Element Method." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1313571236.

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Tinari, Paul D. D. "It is possible to use some of the basic equations of mathematical physics to model time and space varying sociological phenomena. Thèse annexe." Doctoral thesis, Universite Libre de Bruxelles, 1989. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/213238.

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50

McNally, Douglas M. II. "A NEW ALGORITHM FOR THE TIME EVOLUTION OF QUANTUM TRAJECTORY SIMULATIONS AND PHYSICALLY MOTIVATED ERROR MODELS IN 1D QUANTUM CELLULAR AUTOMATA." Miami University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=miami1407344625.

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