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Pihnastyi, O. M., and V. D. Khodusov. "Stochastic equation of the technological process." Thesis, Igor Sikorsky Kyiv Polytechnic Institute, 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/39059.
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This document presents the construction of a stochastic equation for the process of manufacturing products on a production line. We base our research on the synchronized production line. The minimum size of the inter-operational storage is determined, at which the continuous production is possible. The stochastic equation of the production process is written in canonical form. The definition of the diffusion coefficient for the time of processing of subjects of labour.
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Fornasaro, Federico. "The Krylov Equation and Filtering of Stochastic Diffusion Processes." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/21741/.
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La presente tesi ha lo scopo di analizzare alcuni aspetti rilevanti della teoria delle equazioni differenziali stocastiche e, partendo da essi, ricavare risultati di esistenza e unicità, formule di rappresentazione per soluzioni di SPDE e proprietà notevoli sull'attesa e la misura condizionata legate al problema del filtering di un processo stocastico. Nella prima parte, dopo aver dato la definizione di integrale di Ito backward e di spazio di Sobolev pesato, studieremo sotto quali ipotesi una particolare SPDE, detta equazione di Krylov, ammette soluzione r-generalizzata e classica. Nella seconda parte verranno invece illustrati alcuni risultati riguardanti il problema del calcolo dell'attesa condizionata di un processo stocastico diffusivo X rispetto a una sigma-algebra generata da un processo osservabile Y, evidenziando il legame tra la densità di filtering associata alla misura condizionata di X e le soluzioni r-generalizzate di problemi di Cauchy di tipo forward e backward.
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Prömel, David Johannes. "Robust stochastic analysis with applications." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2015. http://dx.doi.org/10.18452/17373.
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Diese Dissertation präsentiert neue Techniken der Integration für verschiedene Probleme der Finanzmathematik und einige Anwendungen in der Wahrscheinlichkeitstheorie. Zu Beginn entwickeln wir zwei Zugänge zur robusten stochastischen Integration. Der erste, ähnlich der Ito’schen Integration, basiert auf einer Topologie, erzeugt durch ein äußeres Maß, gegeben durch einen minimalen Superreplikationspreis. Der zweite gründet auf der Integrationtheorie für rauhe Pfade. Wir zeigen, dass das entsprechende Integral als Grenzwert von nicht antizipierenden Riemannsummen existiert und dass sich jedem "typischen Preispfad" ein rauher Pfad im Ito’schen Sinne zuordnen lässt. Für eindimensionale "typische Preispfade" wird sogar gezeigt, dass sie Hölder-stetige Lokalzeiten besitzen. Zudem erhalten wir Verallgemeinerungen von Föllmer’s pfadweiser Ito-Formel. Die Integrationstheorie für rauhe Pfade kann mit dem Konzept der kontrollierten Pfade und einer Topologie, welche die Information der Levy-Fläche enthält, entwickelt werden. Deshalb untersuchen wir hinreichende Bedingungen an die Kontrollstruktur für die Existenz der Levy-Fläche. Dies führt uns zur Untersuchung von Föllmer’s Ito-Formel aus der Sicht kontrollierter Pfade. Para-kontrollierte Distributionen, kürzlich von Gubinelli, Imkeller und Perkowski eingeführt, erweitern die Theorie rauher Pfade auf den Bereich von mehr-dimensionale Parameter. Wir verallgemeinern diesen Ansatz von Hölder’schen auf Besov-Räume, um rauhe Differentialgleichungen zu lösen, und wenden die Ergebnisse auf stochastische Differentialgleichungen an. Zum Schluß betrachten wir stark gekoppelte Systeme von stochastischen Vorwärts-Rückwärts-Differentialgleichungen (FBSDEs) und erweitern die Theorie der Existenz, Eindeutigkeit und Regularität der sogenannten Entkopplungsfelder auf Markovsche FBSDEs mit lokal Lipschitz-stetigen Koeffizienten. Als Anwendung wird das Skorokhodsche Einbettungsproblem für Gaußsche Prozesse mit nichtlinearem Drift gelöst.In this thesis new robust integration techniques, which are suitable for various problems from stochastic analysis and mathematical finance, as well as some applications are presented. We begin with two different approaches to stochastic integration in robust financial mathematics. The first one is inspired by Ito’s integration and based on a certain topology induced by an outer measure corresponding to a minimal superhedging price. The second approach relies on the controlled rough path integral. We prove that this integral is the limit of non-anticipating Riemann sums and that every "typical price path" has an associated Ito rough path. For one-dimensional "typical price paths" it is further shown that they possess Hölder continuous local times. Additionally, we provide various generalizations of Föllmer’s pathwise Ito formula. Recalling that rough path theory can be developed using the concept of controlled paths and with a topology including the information of Levy’s area, sufficient conditions for the pathwise existence of Levy’s area are provided in terms of being controlled. This leads us to study Föllmer’s pathwise Ito formulas from the perspective of controlled paths. A multi-parameter extension to rough path theory is the paracontrolled distribution approach, recently introduced by Gubinelli, Imkeller and Perkowski. We generalize their approach from Hölder spaces to Besov spaces to solve rough differential equations. As an application we deal with stochastic differential equations driven by random functions. Finally, considering strongly coupled systems of forward and backward stochastic differential equations (FBSDEs), we extend the existence, uniqueness and regularity theory of so-called decoupling fields to Markovian FBSDEs with locally Lipschitz continuous coefficients. These results allow to solve the Skorokhod embedding problem for a class of Gaussian processes with non-linear drift.
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Ben, Ghorbal Anis. "Fondements algébriques des probabilités quantiques et calcul stochastique sur l'espace de Fock booléen." Nancy 1, 2001. http://www.theses.fr/2001NAN10009.
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Ce mémoire est divisé en trois grandes parties. La première est consacrée essentiellement à l'étude des produits en probabilités quantiques. Nous donnons une classification complète à l'aide du produit universel défini par un ensemble d'axiomes canoniques dans les différentes catégories d'algèbres associatives. Ceci nous permet aussi de définir la notion d'indépendance stochastique non-commutative. En particulier nous démontrons que les seuls produits sont les produits tensoriel (classique), libre et booléen. La seconde partie est motivée directement par la première. Elle est consacrée à l'étude des processus de Lévy sur les groupes duaux de D. Voiculescu. Ce nouveau concept généralise la théorie des processus de Lévy sur les algèbres de Hopf (groupes quantiques) où la seule notion d'indépendance est donnée par le produit tensoriel. Ce principe nous fournit l'outil principal pour montrer qu'un processus de Lévy sur un groupe dual est déterminé par son générateur. Comme application directe, nous donnons une réalisation des processus de Lévy additifs sur les trois espaces de Fock (bosonique, libre et booléen). La troisième partie est consacrée au développement du calcul stochastique quantique sur l'espace de Fock booléen. En particulier nous introduisons l'intégrale stochastique et nous donnons une formule d'Itô quantique. Nous construisons aussi les solutions de l'équation différentielle stochastique quantique au sens de R. L. Hudson et K. R. Parthasarathy. Finalement nous construisons les dilatations des semi-groupes complètement positifs.
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Fan, Qianzhu. "Stochastic heat equations with Markovian switching." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/stochastic-heat-equations-with-markovian-switching(8958d026-671e-4c63-a639-b4a7b120a968).html.
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This thesis consists of three parts. In the first part, we recall some background theory that will be used throughout the thesis. In the second part, we studied the existence and uniqueness of solutions of the stochastic heat equations with Markovian switching. In the third part, we investigate the properties of solutions, such as Feller property, strong Feller property and stability.
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Zheng, Bing. "Incorporating equation solving into unification through stratified term rewriting." Thesis, Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/52096.
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This thesis studies equational theories incorporated into unification and describes STAR, a stratified term rewriting system that achieves a full integration. STAR is an advance over existing systems because it integrates an equational theory with unification at a lower, more fundamental level. Certain properties of STAR are proven including termination and confluence.
We also discuss the algorithmic complexity of the reduction algorithm, a vital component of STAR. We compare our system with narrowing and discuss the merits and drawbacks of each technique.
Since our system is an experimental integration of equation solving and unification, we are not concerned with the efficiency of the implementation. We do propose, however, some future improvements.Master of Science
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Zimmermann, Nils E. R., Timm J. Zabel, and Frerich J. Keil. "Transport into zeolite nanosheets: diffusion equations put to test." Diffusion fundamentals 20 (2013 ) 53, S. 1-2, 2013. https://ul.qucosa.de/id/qucosa%3A13629.
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Higham, Jeffrey. "An investigation into the de broglie bohm approach to the dirac equation." Thesis, University of Portsmouth, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.516158.
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Davis, Benjamin J. "A study into discontinuous Galerkin methods for the second order wave equation." Thesis, Monterey, California: Naval Postgraduate School, 2015. http://hdl.handle.net/10945/45836.
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Approved for public release; distribution is unlimitedThere are numerous numerical methods for solving different types of partial differential equations (PDEs) that describe the physical dynamics of the world. For instance, PDEs are used to understand fluid flow for aerodynamics, wave dynamics for seismic exploration, and orbital mechanics. The goal of these numerical methods is to approximate the solution to a continuous PDE with an accurate discrete representation. The focus of this thesis is to explore a new Discontinuous Galerkin (DG) method for approximating the second order wave equation in complex geometries with curved elements. We begin by briefly highlighting some of the numerical methods used to solve PDEs and discuss the necessary concepts to understand DG methods. These concepts are used to develop a one- and two-dimensional DG method with an upwind flux, boundary conditions, and curved elements. We demonstrate convergence numerically and prove discrete stability of the method through an energy analysis.
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Ashworth, Eileen. "Heat flow into underground openings: Significant factors." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185768.
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This project investigates the heat flow from the rock into ventilating airways by studying various parameters. Two approaches have been used: laboratory measurement of thermal properties to study their variation, and analytic and numerical models to study the effect of these variations on the heat flow. Access to a heat-flux system and special treatment of contact resistance has provided the opportunity to study thermal conductivity as a function of moisture contained in rock specimens. For porous sandstone, tuff, and concretes, thermal conductivity can double when the specimens are soaked; the functional dependence of conductivity on moisture for the first two cases is definitely non-linear. Five previous models for conductivity as a function of porosity are shown not to explain this new phenomenon. A preliminary finite element model is proposed which explains the key features. Other variations of conductivity with applied pressure, location, constituents, weathering or other damage, and anisotropy have been measured. In the second phase of the research, analytical and numerical methods have been employed to consider the effects of the variation in the thermal properties plus the use of insulation on the heat flow from the rock into the ventilated and cooled airways. Temperature measurements taken in drill holes at a local mine provide confirmation for some of the models. Results have been provided in a sensitivity analysis mode so that engineers working on other projects can see which parameters would require more detailed consideration. The thermal conductivity of the rock close to the airways is a key factor in affecting heat loads. Dewatering and the use of insulation, such as lightweight foamed shotcretes, are recommended.
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Tannenbaum, Stacey L. "An Investigation into Equations for Estimating Water Requirements and the Development of New Equations for Predicting Total Water Intake." FIU Digital Commons, 2011. http://digitalcommons.fiu.edu/etd/338.
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The primary purpose of this study was to investigate agreement among five equations by which clinicians estimate water requirements (EWR) and to determine how well these equations predict total water intake (TWI). The Institute of Medicine has used TWI as a measure of water requirements. A secondary goal of this study was to develop practical equations to predict TWI. These equations could then be considered accurate predictors of an individual’s water requirement.
Regressions were performed to determine agreement between the five equations and between the five equations and TWI using NHANES 1999-2004. The criteria for agreement was 1) strong correlation coefficients between all comparisons and 2) regression line that was not significantly different when compared to the line of equality (x=y) i.e., the 95% CI of the slope and intercept must include one and zero, respectively. Correlations were performed to determine association between fat-free mass (FFM) and TWI. Clinically significant variables were selected to build equations for predicting TWI. All analyses were performed with SAS software and were weighted to account for the complex survey design and for oversampling.
Results showed that the five EWR equations were strongly correlated but did not agree with each other. Further, the EWR equations were all weakly associated to TWI and lacked agreement with TWI. The strongest agreement between the NRC equation and TWI explained only 8.1% of the variability of TWI. Fat-free mass was positively correlated to TWI. Two models were created to predict TWI. Both models included the variables, race/ethnicity, kcals, age, and height, but one model also included FFM and gender. The other model included BMI and osmolality. Neither model accounted for more than 28% of the variability of TWI. These results provide evidence that estimates of water requirements would vary depending upon which EWR equation was selected by the clinician. None of the existing EWR equations predicted TWI, nor could a prediction equation be created which explained a satisfactory amount of variance in TWI. A good estimate of water requirements may not be predicted by TWI. Future research should focus on using more valid measures to predict water requirements.
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George, Benjamin Thomas. "Extensions of the General Linear Model into Methods within Partial Least Squares Structural Equation Modeling." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc862733/.
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The current generation of structural equation modeling (SEM) is loosely split in two divergent groups - covariance-based and variance-based structural equation modeling. The relative newness of variance-based SEM has limited the development of techniques that extend its applicability to non-metric data. This study focuses upon the extension of general linear model techniques within the variance-based platform of partial least squares structural equation modeling (PLS-SEM). This modeling procedure receives it name through the iterative PLS‑SEM algorithm's estimates of the coefficients for the partial ordinary least squares regression models in both the measurement model and the overall structural model. This research addresses the following research questions: (1) What are the appropriate measures for data segmentation within PLS‑SEM? (2) What are the appropriate steps for the analysis of rank-ordered path coefficients within PLS‑SEM? and (3) What is an appropriate model selection index for PLS‑SEM? The limited type of data to which PLS-SEM is applicable suggests an opportunity to extend the method for use with different data and as a result a broader number of applications. This study develops and tests several methodologies that are prevalent in the general linear model (GLM). The proposed data segmentation approaches posited and tested through post hoc analysis of structural model. Monte Carlo simulation allows demonstrating the improvement of the proposed model fit indices in comparison to the established indices found within the SEM literature. These posited PLS methods, that are logical transfers of GLM methods, are tested using examples. These tests enable demonstrating the methods and recommending reporting requirements.
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McDermott, Martin Francis. "An investigation into the effects of introducing transverse momentum cutoffs on the BFKL equation." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308657.
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Cheng, Ching-Chung. "Investigations into Green's function as inversion-free solution of the Kriging equation, with Geodetic applications." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1095792962.
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Thesis (Ph. D.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains ix, 125 p.; also includes graphics (some col.). Includes bibliographical references (p. 101-103).
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Van, der Merwe John. "An experimental investigation into the validity of Leeson's equation for low phase noise oscillator design." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5424.
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Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2010.Thesis presented in partial fulfilment of the requirements for the degree Master of Science in Engineering at the University of Stellenbosch
ENGLISH ABSTRACT: In 1966, D.B. Leeson presented his model on phase noise in a letter entitled A Simple Model of Feedback Oscillator Noise Spectrum. This model usually requires an additional e ffective noise figure in order to conform with measured results. (This e ffective noise fi gure has to be determined by means of curve-fi tting Leeson's model with the measured results.) The model is, however, relatively simple to use, compared with other more accurate phase noise models that have since been developed and which can only be solved numerically with the aid of computers. It also gives great insight regarding component choices during the design process. Therefore several experiments were conducted in order to determine conditions under which Leeson's model may be considered valid and accurate. These experiments, as well as the conclusions drawn from their results, are discussed in this document.
AFRIKAANSE OPSOMMING: In 1966 stel D.B. Leeson sy faseruis model bekend in 'n brief getiteld A Simple Model of Feedback Oscillator Noise Spectrum. Hierdie model vereis gewoonlik die gebruik van 'n bykomende e ektiewe ruissyfer, sodat die model ooreenstem met die gemete resultate. (Hierdie e ektiewe ruissyfer kan slegs bepaal word deur middel van krommepassings tussen Leeson se model en die gemete resultate.) Die model is egter relatief eenvoudig om te gebruik in teenstelling met ander, meer akkurate, faseruis modelle wat sedertdien ontwikkel is en slegs met behulp van rekenaars opgelos kan word. Dit bied ook onoortre ike insig ten opsigte van komponent keuses tydens die ontwerpsproses. Om hierdie rede is verskeie eksperimente uitgevoer met die doel om toestande te identi seer waaronder Leeson se model as geldig en akkuraat geag kan word. Hierdie eksperimente, asook die gevolgtrekkings wat van hul resultate gemaak is, word in hierdie dokument behandel.
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Randrianarivony, Maharavo. "The ITL programming interface toolkit." Universitätsbibliothek Chemnitz, 2007. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200700254.
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This document serves as a reference for the beta version of our evaluation
library ITL. First, it describes a library which gives an easy way for
programmers to evaluate the 3D image and the normal vector corresponding to
a parameter value which belongs to the unit square. The API functions which
are described in this document let programmers make those
evaluations without the need to understand the underlying CAD complica-
tions. As a consequence, programmers can concentrate on their own scien-
tific interests. Our second objective is to describe the input which is a set
of parametric four-sided surfaces that have the structure required by some
integral equation solvers.
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Wessels, Gert Jermia Cornelus. "A numerical and analytical investigation into non-Hermitian Hamiltonians." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/2894.
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Thesis (MSc (Physical and Mathematical Analysis))--University of Stellenbosch, 2009.In this thesis we aim to show that the Schr odinger equation, which is a boundary eigenvalue problem, can have a discrete and real energy spectrum (eigenvalues) even when the Hamiltonian is non-Hermitian. After a brief introduction into non-Hermiticity, we will focus on solving the Schr odinger equation with a special class of non-Hermitian Hamiltonians, namely PT - symmetric Hamiltonians. PT -symmetric Hamiltonians have been discussed by various authors [1, 2, 3, 4, 5] with some of them focusing speci cally on obtaining the real and discrete energy spectrum. Various methods for solving this problematic Schr odinger equation will be considered. After starting with perturbation theory, we will move on to numerical methods. Three di erent categories of methods will be discussed. First there is the shooting method based on a Runge-Kutta solver. Next, we investigate various implementations of the spectral method. Finally, we will look at the Riccati-Pad e method, which is a numerical implemented analytical method. PT -symmetric potentials need to be solved along a contour in the complex plane. We will propose modi cations to the numerical methods to handle this. After solving the widely documented PT -symmetric Hamiltonian H = p2 (ix)N with these methods, we give a discussion and comparison of the obtained results. Finally, we solve another PT -symmetric potential, illustrating the use of paths in the complex plane to obtain a real and discrete spectrum and their in uence on the results.
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Ristola, A. (Annu). "Insights into consumers' emerging interest in mobile services." Doctoral thesis, Oulun yliopisto, 2010. http://urn.fi/urn:isbn:9789514263644.
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Abstract
The present study develops our understanding of consumers’ emerging interest in novel mobile services by adopting two approaches. First, structural equation modeling is used as a statistical tool to create a context-sensitive model for consumer acceptance of novel mobile services. Secondly, the study creates an interpretive framework of contemporary consumer culture to help understand how consumers construct their emerging practices in novel mobile services based on their actual experiences.
The empirical data was gathered at a Housing Fair, where a Mobile Fair Diary was piloted, and it is that Mobile Fair Diary application that provides the selected tool of the empirical study. Therefore, real user experience played a significant role in how our consumers perceived mobile services and the way the cultural discourse was produced. The model developed indicates that performance expectancy, effort expectancy, anxiety, trust and attitude have an impact on consumers’ intention to use mobile services. Furthermore, the various representations related to mobile services were identified in order to understand emerging practices.
Consumers are likely to change the routines involved in the management of information if useful alternatives are available to them. An ongoing insecurity emerging from technology change is often a characteristic of the contemporary life of consumers. On the one hand, consumers are dependent on technology, but on the other hand, do not fully understand it. Therefore, consumers have to be active to keep up with the continuous changes going on around them. Furthermore, consumers need support from the service provider and their social context. Consumers should also believe in their own capability to learn and their power to make choices, which will result in changes to their practices.
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Degerli, Mustafa. "Identifying Factors Influencing The Acceptance Of Processes: An Empirical Investigation Using The Structural Equation Modeling Approach." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614321/index.pdf.
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In this research, it was mainly aimed to develop an acceptance model for processes, namely the process acceptance model (PAM). For this purpose, a questionnaire, comprising 3-part and 81-question, was developed to collect quantitative and qualitative data from people having relationships with certain process-focused models and/or standards (CMMI, ISO 15504, ISO 9001, ISO 27001, AQAP-160, AQAP-2110, and/or AS 9100). To revise and refine the questionnaire, expert reviews were ensured, and a pilot study was conducted with 60 usable responses. After reviews, refinements and piloting, the questionnaire was deployed to collect data and in-total 368 usable responses were collected from the people. Here, collected data were screened concerning incorrectly entered data, missing data, outliers and normality, and reliability and validity of the questionnaire were ensured. Partial least squares structural equation modeling (PLS SEM) was applied to develop the PAM. In this context, exploratory and confirmatory factor analyses were applied, and the initial model was estimated and evaluated. The initial model was modified as required by PLS SEM, and confirmatory factor analysis was repeated, and the modified final model was estimated and evaluated. Consequently, the PAM, with 18 factors and their statistically significant relationships, was developed. Furthermore, descriptive statistics and t-tests were applied to discover some interesting, meaningful, and important points to be taken into account regarding the acceptance of processes. Moreover, collected quantitative data were analyzed, and three additional factors were discovered regarding the acceptance of processes. Besides, a checklist to test and/or promote the acceptance of processes was established.
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Loughran, Thomas Ivan Powell. ""A values based electorate?" : how do voters in West European democracies convert their political values into vote choice preferences?" Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/a-values-based-electoratehow-do-voters-in-west-european-democracies-convert-their-political-values-into-vote-choice-preferences(b1716c93-c730-41e8-acfb-846bb2d51fcd).html.
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It has long been argued that underlying values should hold a central role in political analysis. This would seem particularly relevant in an era of de-alignment and catch-all parties in which political actors often make direct values orientated appeals to the electorate. With the expansion in appropriate data and measures available to empirical researchers, the last two decades have seen a substantial increase in the number of studies directly addressing the values-voting relationship. Values based explanations of vote choice have contributed to a more nuanced understanding of the processes underlying voter preferences and the structure of public opinion within democratic electorates. This existing empirical literature has generally focused on analysing the role of values on voting in single electoral contexts. While this approach has generated many useful findings that establish the role of values in differentiating political choice, it has only partially explored the contextual mechanisms through which values influence vote choice. This is necessary in order to understand under what political conditions values are likely to become more relevant to vote choice decisions. This thesis is an attempt to address three aspects of this gap in the cross-national research literature on values and voting using analyses of data from the 1990 and 2008 waves of the European Values Survey. Firstly it provides a cross-national analysis of core political values that enables a comparison of the role of values in structuring electoral competition across 15 West European countries. Secondly, it estimates the role that left-right political identity has in mediating the influence of values on vote choice using a structural path model. This provides a cross-national test of this mechanism and therefore assesses variation in the values-voting relationship across different national contexts. Thirdly, the thesis provides a systematic empirical analysis of the influence of political context on the values-voting relationship by testing the effect that macro level system factors, such as polarisation and the number of parties, have on the influence of values. The headline findings of the thesis are that political values are dynamic constructs that can demonstrate subtle variations in the preferences of voters across different electoral contexts. Political values have a multi-dimensional influence on electoral choice; with variation in voter preferences being highlighted by both value differentiation (having opposite preferences for the same value dimension) and emphasis (having a preference for different values). Left-right identity can act as both a mediator and a confounder of political values influence on vote choice. Political context is primarily relevant to the influence of values on voting through the content of supply side party competition as opposed to the structure of that competition. Overall, the study argues the findings show that supply side political context plays a crucial role in defining the parameters and strength of the values-voting relationship in each specific electoral arena.
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Fode, Adamou M. "A Discontinuous Galerkin - Front Tracking Scheme and its Optimal -Optimal Error Estimation." Bowling Green State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1399902459.
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Kuncoro, Andreas. "Employing Quality Management Principles to Improve the Performance of Educational Systems: An Empirical Study of the Effect of ISO 9001 Standard on Teachers and Administrators Performance in the Indonesian Vocational Education System." Doctoral diss., University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5966.
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ISO 9001 has been world widely implemented in both manufacturing and service organizations. A lot of studies have been conducted to investigate the effects of ISO 9001 implementation on the performance of these organizations. Most of these studies show that ISO 9001 implementation realized positive operational improvements and financial success.
Building on the merits of successful implementation of ISO 9001 quality management system in manufacturing and service, educational institutions have been attempted to adopt it in their operations. Even though there are studies relating ISO implementation to education, no research has been done to investigate the effects of ISO 9001 at the individual level.
The objective of this research is to investigate the effects of ISO 9001 quality management implementation on the performance of administrators and teachers. The Indonesian vocational education system is selected as a case example as there is a significant number of such institutions in Indonesia that attempt to achieve ISO certification and there is a national need to improve the performance of vocational education. It is a challenge to assess objectively the degree of ISO 9001 implementation in this specific educational context because of the size and diversity. This study relies on survey that measures the respondents' perception. Hence, this study applies a self-reported survey based performance measurement. The questionnaires are developed based on extensive literature review. Partial Least Squares Structural Equation Modeling (PLSSEM) has been used to examine the relationships between the different elements of quality management systems, quality culture; administrator and teacher performances.
The study is able to examine multiple interrelated dependence and subsequent relationships simultaneously among examined factors such as teacher and administrator performance, existing quality culture and ISO principles; and to incorporate variables that cannot be directly measured, such as leadership, for example. The findings of this study show that ISO 9001 implementation has positive significant effect on the performance of the vocational school administrator and teacher. The study also identifies key influencing elements of the ISO quality management system and examines their direct and indirect relationships with teacher and administrator performances. This study is expected to improve the current practices in implementing ISO and quality culture in any educational settings, specifically in the case of vocational educational system.Ph.D.
Doctorate
Industrial Engineering and Management Systems
Engineering and Computer Science
Industrial Engineering
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Eraslan, Elvan. "Implementation Of Different Flux Evaluation Schemes Into A Two-dimensional Euler Solver." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607704/index.pdf.
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This study investigates the accuracy and efficiency of several flux splitting methods for the compressible, two-dimensional Euler equations. Steger-Warming flux vector splitting method, Van Leer flux vector splitting method, The Advection Upstream Splitting Method (AUSM), Artificially Upstream Flux Vector Splitting Scheme (AUFS) and Roe&rsquos flux difference splitting schemes were implemented using the first- and second-order reconstruction methods. Limiter functions were embedded to the second-order reconstruction methods. The flux splitting methods are applied to subsonic, transonic and supersonic flows over NACA0012 airfoil, as well as subsonic, transonic and supersonic flows in a channel. The comparison of the obtained results with each other and the ones in the literature is presented. The advantages and disadvantages of each scheme among others are identified.
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Musta, Mustafa Nail. "Implementation Of Turbulence Models Into A Navier-stokes Solver." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/2/12605357/index.pdf.
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In order to handle turbulent flow problems, one equation turbulence models are implemented in to a previously developed explicit, Reynolds averaged Navier-Stokes solver. Discretization of Navier-Stokes solver is based on cell-vertex finite volume formulation combined with single step Lax-Wendroff numerical method which is second order accurate in space. Turbulent viscosity is calculated by using one equation Spalart-Allmaras and Baldwin-Barth turbulence transport equations. For the discretization of Spalart-Allmaras and Baldwin-Barth equations, both finite volume scheme which is used for Navier-Stokes equation in this work and explicit finite difference discretization method are used.
In order to increase the convergence rate of the solver, local time stepping technique is applied. Stabilization of non-physical oscillations resulting from the numerical scheme is maintained by adding second and fourth order artificial smoothing terms.
Three test cases are considered. In order to validate the accuracy of the Navier-Stokes solver, solver is tested over a laminar flat plate. The results are compared with analytical solutions. Later, in order to check the performance of the turbulence models, turbulent flow over flat plate and turbulent transonic flow over NACA-0012 airfoil are handled. For turbulent flow over flat plate obtained results are compared with analytical and empirical solutions, whereas for transonic turbulent flow obtained results are compared with numerical and experimental solutions.
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Cañedo, Giselle Ramirez. "Mapa de iso-velocidades : uma ferramenta para o controle das vibrações nas pedreiras." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/3/3134/tde-08072014-121202/.
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Com o crescimento urbano ao redor das minerações surgiram novos problemas como o desconforto dos vizinhos com vibrações, que podem provocar danos nas estruturas das casas, a poeira, os ultralançamento, a sobrepressão atmosférica, entre outros. Atualmente no Brasil as restrições ambientais são cada vez mais rígidas e são exigidos mais monitoramentos sismográficos como medida de controle ambiental. A Geosonic Inc. foi a primeira a usar o sistema de mapa de iso-velocidades, mas seu uso não é prática corrente no Brasil devido ao elevado custo de instrumentação e de operação no campo. Iramina (2002) desenvolveu um método com equações de carga-distância simulando um mapa de iso-velocidades. O objetivo deste trabalho é verificar a metodologia proposta por Iramina (2002), que construiu mapas de iso-velocidades usando oito monitoramentos unidirecionais para oito detonações diferentes e sequenciais numa mesma bancada e analisar alternativas para a construção dos mapas de iso-velocidade. Neste trabalho foram monitoradas quatro detonações e em cada uma delas, quatro direções diferentes foram selecionadas utilizando um total de 20 sismógrafos. As detonações avaliadas foram todas na mesma bancada e com características similares. Para cada direção foram estimados os parâmetros da equação carga-distância e foram construídos e comparados diferentes mapas de iso-velocidade. Conclui-se que a disposição dos geofones deve-se adequar aos objetivos do monitoramento. Oito a quinze geofones alinhados são adequados para uma curva carga-distância. Sessenta e quatro ou mais geofones, bem distribuídos espacialmente, podem gerar um mapa de iso-velocidades referente a uma única detonação. A alta variabilidade das características dos maciços rochosos parece não permitir bons resultados quando os sismógrafos não são bem distribuídos ao redor da detonação.The urban growth around the open pit mines causes some problems hard to solve due to possible damage to structures built as result of unwanted ground vibration propagation, blast overpressure, flyrocks, water contamination and also particulate matter dispersion. Currently in Brazil, the environmental constraints are increasingly rigid and it is required seismographic monitoring as a measure of environmental control. Geosonic Inc. was the first to use the iso-seismic maps, but this technique is not commonly used in Brazil due to the high cost of instrumentation and field operation. Iramina (2002) developed a model of vibration predictor equations that simulates an iso-seismic map. Thus, the objective of this work is to verify the methodology developed by Iramina (2002), who implemented an iso-seismic map from eight unidirectional measurements in eight different and sequential detonations in the same bench and analyze alternatives for the construction of iso-seismic maps. Herein were monitored four detonations with four directions in each and 20 seismographs at most. All detonations were monitored in the same bench and with similar characteristics. For each direction were estimated the parameters of the vibration predictor equations and from these equations were obtained and compared different iso-seismic maps. Then, it is concluded that the arrangement of geophones should suit to the objectives of monitoring. In this sense, eight to fifteen aligned geophones are suitable for a good load-distance curve, sixty-four geophones or more spatially well distributed, must generate a iso-seismic map corresponding to a single detonation. The high variability of the characteristics of the rock mass does not seem to allow good results when the seismograph are not well distributed around the detonation.
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Sirvent, Mathias [Verfasser], Alexander [Akademischer Betreuer] Martin, Alexander [Gutachter] Martin, Winnifried [Gutachter] Wollner, and Sven [Gutachter] Leyffer. "Incorporating Differential Equations into Mixed-Integer Programming for Gas Transport Optimization / Mathias Sirvent ; Gutachter: Alexander Martin, Winnifried Wollner, Sven Leyffer ; Betreuer: Alexander Martin." Erlangen : FAU University Press, 2018. http://d-nb.info/1163806862/34.
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Lee, Richard Todd. "A novel method for incorporating periodic boundaries into the FDTD method and the application to the study of structural color of insects." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29772.
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Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009.Committee Chair: Smith, Glenn; Committee Member: Buck, John; Committee Member: Goldsztein, Guillermo; Committee Member: Peterson, Andrew; Committee Member: Scott, Waymond. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Schwanke, Peter. "Implementation into DIVIMP of a drift-kinetic model derived from the Fokker-Planck equation to examine the parallel-to-B velocity component of impurity ions in divertor-Tokamak plasmas." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ62896.pdf.
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Oubanas, Hind. "Variational assimilation of satellite data into a full Saint-Venant based hydraulic model in the context of ungauged basins." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30102.
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Ce sujet de thèse s'inscrit dans le cadre général de la mission satellitaire Surface Water and Ocean Topography (SWOT) et a pour objectif d'évaluer l'apport de l'assimilation de données (AD) variationnelle en utilisant un modèle hydraulique 1.5D basé sur le système d'équations Saint-Venant complet. De plus, la méthode proposée est conçue pour une application dans le contexte général de bassins non instrumentés. Une première analyse de sensibilité avec la méthode de l'adjoint a été effectuée pour évaluer l'influence locale des variables et paramètres d'entrée du modèle sur ses sorties. La réponse du modèle est définie à partir d'une fonction objective des variables d'état. Celle-ci s'avère significativement sensible à la condition limite en débit amont, ainsi qu'aux variables de géomorphologie fluviale; le niveau du lit du fleuve et ses coefficients de frottements. Les sensibilités calculées renseignent sur les sections de contrôle qui ont une influence majeure sur l'hydraulique du fleuve et qui requièrent des relevés ou un calage plus précis. L'estimation du débit des fleuves à partir de données SWOT, a été ensuite étudiée, en utilisant une variante de la méthode conventionnelle '4D-Var'. Celle-ci permet d'estimer simultanément le débit, ainsi que la bathymétrie et les frottements dans le contexte de bassins non instrumentés, observés uniquement depuis l'espace. Deux configurations ont été analysées: (i) les expériences jumelles dans le cadre du fleuve Garonne, puis un cadre plus représentatif des données SWOT, en utilisant (ii) le simulateur SWOT d'hydrologie, sur les fleuves Po et Sacramento. En assimilant des données de hauteur d'eau, la bathymétrie et les frottements sont corrigés localement, permettant une meilleure estimation du débit. Toutefois, les variables estimées (bathymétrie et frottements) sont sujettes au problème d'équifinalité, et ne peuvent être exploitées pour des applications ultérieures. De plus, les résultats obtenus renseignent sur la fréquence temporelle des observations permettant une bonne estimation du débit et qui se doit d'être au moins équivalente au temps caractéristique du fleuve étudié. Pour finir, une nouvelle approche pour le traitement de l'erreur modèle en utilisant l'AD variationnelle a été proposée. Elle implique un traitement implicite basé sur une matrice de covariance des erreurs d'observations modifiée. Le théorème proposé est démontré et illustré par une application à l'équation 1D de Burger généralisée, ainsi qu'au cadre hydraulique en utilisant le modèle 1.5D saint-Venant completThe present thesis investigates the potential of variational data assimilation (DA) in discharge estimation from the future Surface Water and Ocean Topography (SWOT) satellite mission, using a 1.5D full Saint-Venant hydraulic model in the context of fully ungauged basins. Two distinct approaches for treating the model error are being investigated; the extended control vector approach, and a novel approach based on a modified covariance matrix. Adjoint sensitivity analysis was first performed to assess the local influence of the hydraulic model inputs, on the model response, defined using an objective function of the model state. The latter is highly sensitive to the upstream boundary condition on discharge as well as the river bed elevation and roughness coefficient. Sensitivities indicate the control sections of the river that have major influence on the flow hydraulics, which emphasizes the need of accurate measurements and/or at these locations. Second, the estimation of river discharge from simulated SWOT observations using a variant of the conventional variational DA method '4D-Var' has been investigated. The variational DA scheme involves an extended control vector and is developed to apply the method to fully ungauged basins. The method was tested using two experimental set-ups: (i) Observing System Simulation Experiments over the Garonne River and a more realistic and general framework using (ii) the SWOT hydrology simulator, which simulates the radar system on-board the satellite, over the Po and Sacramento Rivers. Water surface elevation was assimilated leading to local improvements on bathymetry and roughness which allowed successful estimation of discharge. Nevertheless, the estimates of the space distributed variables are subjected to the equifinality issue which may prevent their use for subsequent applications. Moreover, results emphasize that successful estimation of discharge over the whole study period requires an observation frequency comparable to the characteristic time of the hydraulic system. Finally, a novel method for the treatment of the model error using the variational approach is proposed. Based on the 'nuisance parameter' idea, it allows implicit treatment of the model error by using a modified observation covariance matrix. The equivalency theorem substantiating the method has been proved. A case of the biased model error is also considered. Numerical experiments involving the 1D generalized Burger's equation and the 1.5D full Saint-Venant equations illustrate the presented theory
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Mogos, Mulubrhan Fisseha. "Translation and Adaptation of the Center for Epidemiologic Studies-Depression (CES-D) Scale Into Tigrigna Language for Tigrigna Speaking Eritrean Immigrants in the United States." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3251.
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ABSTRACT
Depression is one of the oldest known mental health conditions. It is acknowledged to be a global health problem that affects people from any culture or ethnic group. The prevalence of depression widely varied across countries and cultures. The cross-cultural relevance of the concept of depression, its screening or diagnosis, and cultural equivalence of items used to measure symptoms of depression has been area of research interest. Differences in prevalence rates in depression have been suggested as being due to research artifacts, such as use of instrument developed for one culture to another culture. With the current trend of globalization and increased rate of immigration, the need for measurement scales that can be used cross-culturally is becoming essential. Translation and adaptation of existing tools to different languages is time saving and cost effective than developing a new scale. The Center for Epidemiologic Studies Depression Scale [CES-D; (Radloff, 1977)] has been widely used as a screening tool for depressive symptoms in community and clinical settings. It has been widely accepted and translated to multiple languages and its measurement equivalence tested across groups. This study was designed as a mixed method study. The purpose of this study was three fold: (a) translate and adapt the CES-D scale into Tigrigna Language for use by Tigrigna speaking Eritrean immigrants in the United States using the forward backward translation and cognitive interview techniques (b) test the psychometric properties of the Tigrigna version CES-D scale using confirmatory factor analysis under the framework of structural equation modeling and (c) test measurement equivalence of the scale by comparing data collected from 253 Eritrean immigrants using the Tigrigna version CES-D scale with a secondary data collected from 1918 non Eritrean US citizens using the English version CES-D scale in a separate study. The baseline four factor CES-D scale model originally suggested for the general population fitted the data from both samples. The fit indices for the Tigrigna sample were (χ2 = 299.87, df = 164, RMSEA = .06, SRMR = .06, GFI = .89, and CFI = .98) and for the English sample (χ2 = 1496.81, df = 164, RMSEA = .07, SRMR = .04, GFI = .92, and CFI = .98). The Multi-group confirmatory factor analysis showed reasonably adequate fit (χ2 (328) = 1796.68, RMSEA= .07, SRMR = .06, GFI = .89, CFI = .98). Fourteen of the 20 CES-D items were invariant across the two samples suggesting partial metric invariance. Partial full factor invariance was also supported. In conclusion, the findings of this study provide adequate evidence in support of the applicability of the four factor CES-D scale for measuring depressive symptoms in Tigrigna speaking Eritrean immigrants/refugees in the United States.
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Purohit, Ashish. "An investigation into the use of social media channels within the South African retail banking environment in support of creating and maintaining brand loyalty." Thesis, Rhodes University, 2015. http://hdl.handle.net/10962/d1018920.
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The use of social media in the retail banking environment has changed the way the banking industry communicates with customers, creates sales and performs marketing and operational tasks. Social media strategies need to be aligned to business goals and effectively used to integrate social media as part of the overall marketing strategy. Only by understanding brand loyalty, multi-channel systems and social media channels can marketers effectively implement social media. In measuring brand loyalty, factors that influence customer buying behaviour and components that influence online interaction are essential in engaging different groups of customers in social media. This research study aimed to examine the use of social media within the South African retail banking environment with a focus on creating and maintaining brand loyalty. An exploratory, mixed method research design was employed. Data collection instruments used in the study includes online surveys, structured interviews, and focus groups. Participants consisted of marketing personnel and customers. Three lead/head social media marketing personnel participated in the interview process, 14 marketing personnel took the online survey and 4 participated in a focus group. Participants for the online survey also consisted of 40 customers who were connected through the internet and performed various online banking activities. Data was analysed both quantitatively and qualitatively. Data from the online surveys completed by customers was analysed quantitatively using descriptive analysis, structural equation modelling (SEM) and factor analysis which was performed on the brand loyalty variables and the brand loyalty measures. Content analysis was used to qualitatively analyse data from the structured interviews. Data from the online surveys completed by marketing personnel was analysed quantitatively and qualitatively. Findings indicated that social media forms an integral part of the marketing strategy that needs be aligned with the core business goals. Banks therefore need to focus on creating campaigns that are fun, exciting and appealing to the target market. A culture of innovation and new ideas is essential to grow the product/service. Building brand trust and creating customer satisfaction forms the core of creating brand loyalty on social media. Banks need to be aware of factors that influence customer brand loyalty and components that influence loyalty on social media in order to measure things that matter through analytical tools so that an actionable strategy can be put in place and implemented.
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Morel, Pierre. "Le modèle « water bag » appliqué aux équations cinétiques des plasmas de Tokamak." Thesis, Nancy 1, 2008. http://www.theses.fr/2008NAN10153/document.
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Ce travail a porté sur l'étude des instabilités de gradient de température ioniques (ITG) en géométrie cylindrique, le champ magnétique étant supposé constant et dirigé selon l'axe du cylindre. Une fonction de distribution discrète en forme de marche d'escalier est utilisée pour décrire la direction de vitesse parallèle au champ magnétique. L'équation de Vlasov se résume à un système de type multi fluides couplés par l'équation de quasi neutralité. Chaque fluide est décrit par un système fermé d'équations (continuité, Euler et fermeture adiabatique), caractéristiques d'un fluide incompressible, d'où la dénomination de sac d'eau ou "water bag". Le recours à cette description water bag est particulièrement intéressant dans le cas de problèmes à une seule dimension en vitesse. Ainsi, dans le cas des plasmas fortement magnétisés, un modèle water bag peut se combiner avantageusement aux modèles dits girocinétiques. Les paramètres associés a la représentation water bag ont pu être identifiés et reliés aux grandeurs macroscopiques par le biais d'une méthode originale d'équivalence au sens des moments. L'analyse water bag des ITG a permis de valider le modèle et les méthodes choisies. Ce travail a également permis de montrer que le concept de water bag peut sans problème prendre en compte des effets variés comme ceux liés a l'introduction d?un rayon de Larmor fini, tout comme à la description d'un plasma composé de plusieurs espèces d'ionsA drift-kinetic model in cylindrical geometry has been used to study Ion Temperature Gradients (ITG). The cylindrical plasma is considered as a limit case of a stretched torus. The magnetic field is assumed uniform and constant; it is directed along the axis of the column. A discrete distribution function f taking the form of a multi-step like function is used in place of the continuous distribution function along the parallel velocity direction. With respect to the properties of the Heaviside?s distribution, the Vlasov equation is reduced to a system of fluids coupled by the electromagnetic fields. This model is well suited mainly for problems involving a phase space with one velocity component. In the case of magnetized plasmas it gives an alternative way to study turbulence thanks to the gyro-average whose allows reducing the 3D velocity space into a 1D space. Parameters introduced by the water bag formalism have been linked to physical quantities by an original method of moment-sense equivalence. In the linear approximation, the water bag study of the ITG instability allows an interesting comparison with some well-known analytical results. The water-bag concept is not affected by taking into account Finite Larmor Radius effects. It well describes the case of multi-species plasma
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Baštek, Jozef. "Modelování a zobrazování pomocí blobů." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2011. http://www.nusl.cz/ntk/nusl-237054.
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This thesis deals with blobs modeling and visualizing (iso-surfaces, implicit-surfaces). It includes implementation of full-featured editor of these objects. It provides real-time operations over surfaces. The work also contains its motivation - where this modeling technique comes from, required equations and computations needed for surface rendering and algorithms used for blobs visualization.
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Kothamachu, Varun Bhaskar. "An investigation into dynamic and functional properties of prokaryotic signalling networks." Thesis, University of Exeter, 2016. http://hdl.handle.net/10871/26597.
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In this thesis, I investigate dynamic and computational properties of prokaryotic signalling architectures commonly known as the Two Component Signalling networks and phosphorelays. The aim of this study is to understand the information processing capabilities of different prokaryotic signalling architectures by examining the dynamics they exhibit. I present original investigations into the dynamics of different phosphorelay architectures and identify network architectures that include a commonly found four step phosphorelay architecture with a capacity for tuning its steady state output to implement different signal-response behaviours viz. sigmoidal and hyperbolic response. Biologically, this tuning can be implemented through physiological processes like regulating total protein concentrations (e.g. via transcriptional regulation or feedback), altering reaction rate constants through binding of auxiliary proteins on relay components, or by regulating bi-functional activity in relays which are mediated by bifunctional histidine kinases. This study explores the importance of different biochemical arrangements of signalling networks and their corresponding response dynamics. Following investigations into the significance of various biochemical reactions and topological variants of a four step relay architecture, I explore the effects of having different types of proteins in signalling networks. I show how multi-domain proteins in a phosphorelay architecture with multiple phosphotransfer steps occurring on the same protein can exhibit multistability through a combination of double negative and positive feedback loops. I derive a minimal multistable (core) architecture and show how component sharing amongst networks containing this multistable core can implement computational logic (like AND, OR and ADDER functions) that allows cells to integrate multiple inputs and compute an appropriate response. I examine the genomic distribution of single and multi domain kinases and annotate their partner response regulator proteins across prokaryotic genomes to find the biological significance of dynamics that these networks embed and the processes they regulate in a cell. I extract data from a prokaryotic two component protein database and take a sequence based functional annotation approach to identify the process, function and localisation of different response regulators as signalling partners in these networks. In summary, work presented in this thesis explores the dynamic and computational properties of different prokaryotic signalling networks and uses them to draw an insight into the biological significance of multidomain sensor kinases in living cells. The thesis concludes with a discussion on how this understanding of the dynamic and computational properties of prokaryotic signalling networks can be used to design synthetic circuits involving different proteins comprising two component and phosphorelay architectures.
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Šimák, Jakub. "Měření průtoku vzduchu pomocí víceotvorových rychlostních sond." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219230.
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Master work deals with the measurement of fluid flow (particularly air) pipe, with orifice and multiport averaging probe. The theoretical part is followed by practical, which verifies the properties of the measured system. In a next part of semestral work are verifies the properties of multiport averaging probes Vavra s.r.o. MQS-011 and Rosemount Annubar 485. Measured values from probes are compared.
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Medeiros, Stephen Conroy. "Incorporating Remotely Sensed Data into Coastal Hydrodynamic Models: Parameterization of Surface Roughness and Spatio-Temporal Validation of Inundation Area." Doctoral diss., University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5434.
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This dissertation investigates the use of remotely sensed data in coastal tide and inundation models, specifically how these data could be more effectively integrated into model construction and performance assessment techniques. It includes a review of numerical wetting and drying algorithms, a method for constructing a seamless digital terrain model including the handling of tidal datums, an investigation into the accuracy of land use / land cover (LULC) based surface roughness parameterization schemes, an application of a cutting edge remotely sensed inundation detection method to assess the performance of a tidal model, and a preliminary investigation into using 3-dimensional airborne laser scanning data to parameterize surface roughness. A thorough academic review of wetting and drying algorithms employed by contemporary numerical tidal models was conducted. Since nearly all population centers and valuable property are located in the overland regions of the model domain, the coastal models must adequately describe the inundation physics here. This is accomplished by techniques that generally fall into four categories: Thin film, Element removal, Depth extrapolation, and Negative depth. While nearly all wetting and drying algorithms can be classified as one of the four types, each model is distinct and unique in its actual implementation. The use of spatial elevation data is essential to accurate coastal modeling. Remotely sensed LiDAR is the standard data source for constructing topographic digital terrain models (DTM). Hydrographic soundings provide bathymetric elevation information. These data are combined to form a seamless topobathy surface that is the foundation for distributed coastal models. A three-point inverse distance weighting method was developed in order to account for the spatial variability of bathymetry data referenced to tidal datums. This method was applied to the Tampa Bay region of Florida in order to produce a seamless topobathy DTM. Remotely sensed data also contribute to the parameterization of surface roughness. It is used to develop land use / land cover (LULC) data that is in turn used to specify spatially distributed bottom friction and aerodynamic roughness parameters across the model domain. However, these parameters are continuous variables that are a function of the size, shape and density of the terrain and above-ground obstacles. By using LULC data, much of the variation specific to local areas is generalized due to the categorical nature of the data. This was tested by comparing surface roughness parameters computed based on field measurements to those assigned by LULC data at 24 sites across Florida. Using a t-test to quantify the comparison, it was proven that the parameterizations are significantly different. Taking the field measured parameters as ground truth, it is evident that parameterizing surface roughness based on LULC data is deficient. In addition to providing input parameters, remotely sensed data can also be used to assess the performance of coastal models. Traditional methods of model performance testing include harmonic resynthesis of tidal constituents, water level time series analysis, and comparison to measured high water marks. A new performance assessment that measures a model's ability to predict the extent of inundation was applied to a northern Gulf of Mexico tidal model. The new method, termed the synergetic method, is based on detecting inundation area at specific points in time using satellite imagery. This detected inundation area is compared to that predicted by a time-synchronized tidal model to assess the performance of model in this respect. It was shown that the synergetic method produces performance metrics that corroborate the results of traditional methods and is useful in assessing the performance of tidal and storm surge models. It was also shown that the subject tidal model is capable of correctly classifying pixels as wet or dry on over 85% of the sample areas. Lastly, since it has been shown that parameterizing surface roughness using LULC data is deficient, progress toward a new parameterization scheme based on 3-dimensional LiDAR point cloud data is presented. By computing statistics for the entire point cloud along with the implementation of moving window and polynomial fit approaches, empirical relationships were determined that allow the point cloud to estimate surface roughness parameters. A multi-variate regression approach was chosen to investigate the relationship(s) between the predictor variables (LiDAR statistics) and the response variables (surface roughness parameters). It was shown that the empirical fit is weak when comparing the surface roughness parameters to the LiDAR data. The fit was improved by comparing the LiDAR to the more directly measured source terms of the equations used to compute the surface roughness parameters. Future work will involve using these empirical relationships to parameterize a model in the northern Gulf of Mexico and comparing the hydrodynamic results to those of the same model parameterized using contemporary methods. In conclusion, through the work presented herein, it was demonstrated that incorporating remotely sensed data into coastal models provides many benefits including more accurate topobathy descriptions, the potential to provide more accurate surface roughness parameterizations, and more insightful performance assessments. All of these conclusions were achieved using data that is readily available to the scientific community and, with the exception of the Synthetic Aperture Radar (SAR) from the Radarsat-1 project used in the inundation detection method, are available free of charge. Airborne LiDAR data are extremely rich sources of information about the terrain that can be exploited in the context of coastal modeling. The data can be used to construct digital terrain models (DTMs), assist in the analysis of satellite remote sensing data, and describe the roughness of the landscape thereby maximizing the cost effectiveness of the data acquisition.ID: 031001547; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Adviser: Scott C. Hagen.; Co-adviser: John F. Weishampel.; Title from PDF title page (viewed August 23, 2013).; Thesis (Ph.D.)--University of Central Florida, 2012.; Includes bibliographical references.
Ph.D.
Doctorate
Civil, Environmental and Construction Engineering
Engineering and Computer Science
Civil Engineering
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Habib, Abdulrahman. "A Smart Tale: An Examination of the Smart City Phenomena through the Lens of a Case Study." Thesis, University of North Texas, 2019. https://digital.library.unt.edu/ark:/67531/metadc1538676/.
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This dissertation addresses research questions related to defining a smart city and the associated activities. The general research question is explored in the dissertation via the conduct of three related studies. The finding from these three investigations are presented in the results section as 3 essays that collectively examine the smart city phenomena as it has emerged within the City. Essay 1 assesses building municipal open data capability. The study proposed an Opendata Roadmap Framework to enhance the organization's dynamic capability. The results provide a valuable practical framework to help cities develop open data capability. The results also provide a comparative study or benchmark for similar initiatives with other regional cities and within the nation. Essay 2 measures the residents' understanding and beliefs about smart cities. This portion of the research used a qualitative method that included interviewing residents and city officials to understand their definition of a smart city and what they believe makes a city smart. The interviews focused on understanding resident engagement because it is an important characteristic of a smart city. The gap between the city officials and residents understanding was examined. In addition, the interviews help identify essential factors associated with smart cities like trust in government, perceived security, perceived privacy, trust in technology, and perceived monetary value. Essay 3 examines the acceptance of smart city technologies and factors that affect the adoption of such technologies. This essay uses the insights from the other two essays to propose a smart city Unified Theory of Acceptance and Use of Technology (UTAUT) extension labelled Smart City UTAUT (SC-UTAUT). The new proposed model was tested using a survey method. The 1,786 valid responses were used to test the proposed structural equation model using Smart PLS. Results show a significant relationship between trust in technology, trust in government, perceived monetary value, effort expectancy, self-efficacy, and behavioral intention. The dissertation concludes with a summary of how the three essays make a cumulative contribution to the literature as well as providing practical guidance for becoming a smart city.
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Pimentel, Edgard Almeida. "Um ensaio em teoria dos jogos." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/45/45132/tde-31082010-091851/.
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Esta dissertação aborda a teoria dos jogos diferenciais em sua estreita relação com a teoria das equações de Hamilton-Jacobi (HJ). Inicialmente, uma revisão da noção de solução em teoria dos jogos é empreendida. Discutem-se nesta ocasião as idéias de equilíbrio de Nash e alguns de seus refinamentos. Em seguida, tem lugar uma introdução à teoria dos jogos diferenciais, onde noções de solução como a função de valor de Isaacs e de Friedman são discutidas. É nesta altura do trabalho que fica evidente a conexão entre este conceito de solução e a teoria das equações de Hamilton-Jacobi. Por ocasião desta conexão, é explorada a noção de solução clássica e é exposta uma demonstração do fato de que se um jogo diferencial possuir uma função de valor pelo menos continuamente diferenciável, esta será uma solução da equação de Hamilton-Jacobi associada ao jogo. Este resultado faz uso do princípio da programação dinâmica, devido a Bellman, e cuja demonstração está presente no texto. No entanto, quando a função de valor do jogo é apenas contínua, então embora esta não seja uma solução clássica da equação HJ associada a jogo, vemos que ela será uma solução viscosa, ou solução no sentido da viscosidade - e a esta altura são discutidos os elementos e propriedades desta classe de soluções, um teorema de existência e unicidade e alguns exemplos. Por fim, retomamos o estudo dos jogos diferenciais à luz das soluções viscosas da equação de Hamilton-Jacobi e, assim, expomos uma demonstração de existência da função de valor e do princípio da programação dinâmica a partir das noções da viscosidadeThis dissertation aims to address the topic of Differential Game Theory in its connection with the Hamilton-Jacobi (HJ) equations framework. Firstly we introduce the idea of solution for a game, through the discussion of Nash equilibria and its refinements. Secondly, the solution concept is then translated to the context of Differential Games and the idea of value function is introduced in its Isaacs\'s as well as Friedman\'s version. As the value function is discussed, its relationship with the Hamilton-Jacobi equations theory becomes self-evident. Due to such relation, we investigate the HJ equation from two distinct points of view. First of all, we discuss a statement according to which if a differential game has a continuously differentiable value function, then such function is a classical solution of the HJ equation associated to the game. This result strongly relies on Bellman\'s Dynamic Programming Principle - and this is the reason why we devote an entire chapter to this theme. Furthermore, HJ is still at our sight from the PDE point of view. Our motivation is simple: under some lack of regularity - a value function which is continuous, but not continuously differentiable - a game may still have a value function represented as a solution of the associated HJ equation. In this case such a solution will be called a solution in the viscosity sense. We then discuss the properties of viscosity solutions as well as provide an existence and uniqueness theorem. Finally we turn our attention back to the theory of games and - through the notion of viscosity - establish the existence and uniqueness of value functions for a differential game within viscosity solution theory.
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Bright, Andrew G. "Mechanistic Insights into the Stabilisation of Biopharmaceuticals using Glycine Derivatives. The Effect of Glycine Derivatives on the Crystallisation, Physical Properties and Behaviour of Commonly used Excipients to Stabilise Antigens, Adjuvants and Proteins in the Solid State." Thesis, University of Bradford, 2015. http://hdl.handle.net/10454/15943.
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This dissertation has focused on studying the effect of four glycine derivatives on the solid state properties of mannitol, glycine, and sucrose when freeze dried into blended mixtures. The primary goal was to assess their value for use in the stabilisation of vaccines in the solid state, by examining key physical and chemical characteristics, which have been documented to be beneficial to the stabilisation of biopharmaceutical formulations. The novel excipients; dimethyl glycine, and trimethyl glycine, were shown to retard the crystallisation and increase the overall glass transition temperature, of mannitol, when freeze dried as evidenced by DSC and Powder X-ray diffraction. Mannitol’s glass transition temperature increased from 100C to 12.650C and 13.610C when mixed with methyl-glycine and dimethyl glycine respectively. The glycine derivatives did not show the same effect on sucrose which remained amorphous regardless of the concentration of the other excipient. The different behaviour with the sucrose system was thought to be due to relatively high glass transition temperature of sucrose. Conversely glycine remained highly crystalline due it’s relatively low glass transition temperature. The novel excipient formulations were also assessed for their effect on the aggregation of the adjuvant aluminium hydroxide when freeze dried by Dynamic Light Scattering (DLS).The formulations containing the glycine derivatives all caused a decrease in the aggregation size of the adjuvant from ~26 μm, to 185 nm in the presence of methyl glycine. The effects of lysozyme and viral antigen on the adjuvants were also examined showing that the addition of the virus did not affect the size of the aggregates formed, however lysozyme showed significant decreases in the aggregates formed. Examination of the freezing method were also made showing that faster freezing rates produced smaller aggregates of the adjuvant. When investigating the rate at which the excipients lost water during secondary drying there was evidence of the formation of hydrates of glycine, trimethyl glycine, and mannitol has shown that the glycine derivatives have attributes which would be beneficial in stabilising vaccines in the solid state when freeze dried.
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Bauzet, Caroline. "Etude d'équations aux dérivées partielles stochastiques." Thesis, Pau, 2013. http://www.theses.fr/2013PAUU3007/document.
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Cette thèse s’inscrit dans le domaine mathématique de l’analyse des équations aux dérivées partielles (EDP) non-linéaires stochastiques. Nous nous intéressons à des EDP paraboliques et hyperboliques que l’on perturbe stochastiquement au sens d’Itô. Il s’agit d’introduire l’aléatoire via l’ajout d’une intégrale stochastique (intégrale d’Itô) qui peut dépendre ou non de la solution, on parle alors de bruit multiplicatif ou additif. La présence de la variable de probabilité ne nous permet pas d’utiliser tous les outils classiques de l’analyse des EDP. Notre but est d’adapter les techniques connues dans le cadre déterministe aux EDP non linéaires stochastiques en proposant des méthodes alternatives. Les résultats obtenus sont décrits dans les cinq chapitres de cette thèse : Dans le Chapitre I, nous étudions une perturbation stochastique des équations de Barenblatt. En utilisant une semi- discrétisation implicite en temps, nous établissons l’existence et l’unicité d’une solution dans le cas additif, et grâce aux propriétés de la solution nous sommes en mesure d’étendre ce résultat au cas multiplicatif à l’aide d’un théorème de point fixe. Dans le Chapitre II, nous considérons une classe d’équations de type Barenblatt stochastiques dans un cadre abstrait. Il s’agit là d’une généralisation des résultats du Chapitre I. Dans le Chapitre III, nous travaillons sur l’étude du problème de Cauchy pour une loi de conservation stochastique. Nous montrons l’existence d’une solution par une méthode de viscosité artificielle en utilisant des arguments de compacité donnés par la théorie des mesures de Young. L’unicité repose sur une adaptation de la méthode de dédoublement des variables de Kruzhkov.. Dans le Chapitre IV, nous nous intéressons au problème de Dirichlet pour la loi de conservation stochastique étudiée au Chapitre III. Le point remarquable de l’étude repose sur l’utilisation des semi-entropies de Kruzhkov pour montrer l’unicité. Dans le Chapitre V, nous introduisons une méthode de splitting pour proposer une approche numérique du problème étudié au Chapitre IV, suivie de quelques simulations de l’équation de Burgers stochastique dans le cas unidimensionnelThis thesis deals with the mathematical field of stochastic nonlinear partial differential equations’ analysis. We are interested in parabolic and hyperbolic PDE stochastically perturbed in the Itô sense. We introduce randomness by adding a stochastic integral (Itô integral), which can depend or not on the solution. We thus talk about a multiplicative noise or an additive one. The presence of the random variable does not allow us to apply systematically classical tools of PDE analysis. Our aim is to adapt known techniques of the deterministic setting to nonlinear stochastic PDE analysis by proposing alternative methods. Here are the obtained results : In Chapter I, we investigate on a stochastic perturbation of Barenblatt equations. By using an implicit time discretization, we establish the existence and uniqueness of the solution in the additive case. Thanks to the properties of such a solution, we are able to extend this result to the multiplicative noise using a fixed-point theorem. In Chapter II, we consider a class of stochastic equations of Barenblatt type but in an abstract frame. It is about a generalization of results from Chapter I. In Chapter III, we deal with the study of the Cauchy problem for a stochastic conservation law. We show existence of solution via an artificial viscosity method. The compactness arguments are based on Young measure theory. The uniqueness result is proved by an adaptation of the Kruzhkov doubling variables technique. In Chapter IV, we are interested in the Dirichlet problem for the stochastic conservation law studied in Chapter III. The remarkable point is the use of the Kruzhkov semi-entropies to show the uniqueness of the solution. In Chapter V, we introduce a splitting method to propose a numerical approach of the problem studied in Chapter IV. Then we finish by some simulations of the stochastic Burgers’ equation in the one dimensional case
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Miozzi, Ferrini Francesca. "Experimental study of the Fe-Si-C system and application to carbon rich exoplanet." Electronic Thesis or Diss., Sorbonne université, 2019. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2019SORUS241.pdf.
Full textAbstract:
Plus de 4000 exoplanètes ont été découvertes, orbitant autour d’étoiles ayant différentes compositions. Ces exoplanètes sont détectées et étudiées par observations indirectes qui, dans de nombreux cas, donnent accès aux propriétés principales des planètes: leurs masses et leurs rayons. Ces paramètres peuvent être calculés à partir d’un modèle et comparés à ceux observés. Toutefois, cela est plus difficile pour des planètes qui orbitent autour d’étoiles ayant une composition chimique différente du Soleil, par exemple enrichie en carbone, car les propriétés physiques des carbures (i.e. carbures de silicium ou de fer) sont inconnues. Dans cette étude les systèmes Si-C et Fe-Si-C ont été étudiés entre 20 et 200 GPa et 300-3000 K, en utilisant la diffraction de rayons x et l’analyse chimique des échantillons récupérés pour déterminer les propriétés physiques dans des conditions extrêmes. Dans le système Si-C les équations d’états et les modèles thermiques pour les deux phases de basse et haute pression ont été déterminés. Les résultats ont ensuite été utilisé pour calculer la relation masse-rayon de planètes synthétiques ayant un noyau de fer et un manteau de SiC. Concernant le système Fe-Si-C le diagramme de phase ternaire a été reconstruit. En faisant l’hypothèse d’une composition Fe-Si-C pour un noyau planétaire, quatre différentes séquences de cristallisation ont été démontrées, déterminant des comportements dynamiques très diffèrent. En conclusion la relation masse-rayon n’est pas suffisante pour déterminer la composition et la structure interne des exoplanètes observées mais des données relatives à la chimie du système planétaire sont requisesMore than 4000 exoplanets have been discovered, orbiting around stars with a wide variety of composition. Such planets are detected and studied through indirect methods that in many cases give access to the main properties of the planets: mass and radius. The same parameters can be calculated from a chosen model and compared to the observed ones. However it is difficult for planets orbiting around stars with compositions very different from our Sun, for example carbon enriched, as the physical properties carbides (i.e. silicon carbides and iron carbides) at extreme pressure are unknown. In this work the Si-C and Fe-Si-C systems were studied in the range between 20 and 200 GPa and 300-3000 K employing X-ray diffraction and chemical analyses on the recovered samples were used to determine the physical properties at extreme conditions. In the Si-C system the equations of state and thermal model for both the low pressure and high pressure phases were determined. The results were then used to model a mass radius plot for different archetypal planets with a Fe core and SiC mantle. Regarding the Fe-Si-C system a ternary phase diagram was reconstructed up to 200 GPa and 3000 K. Assuming Fe-Si-C as main component of planetary cores, four different crystallization paths are individuated, giving rise to way different dynamical behaviour. We conclude that using only mass radius relations is not sufficient to determine the interior composition and structure of an observed exoplanet and further data relative to the chemistry are needed, for example the composition of the host star
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Wiedemann, Hartmut. "Cliometrische Untersuchungen zur Bildungsökonomie in Deutschland." Doctoral thesis, Humboldt-Universität zu Berlin, Philosophische Fakultät IV, 2013. http://dx.doi.org/10.18452/16756.
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Das primäre Ziel dieser Dissertation ist es, Belege für die zentrale Hypothese der Humankapi-taltheorie zu finden, dass Investitionen in Bildung, Forschung und Entwicklung einen erhöh-ten Output für die Gesellschaft und für das Individuum generieren. Die dafür notwendige Untersuchung wird anhand langer Zeitreihen für Deutschland mit Hilfe cliometrischer und ökonometrischer Methoden durchgeführt und das Ergebnis einer kritischen Würdigung unterzogen. Zur Einstimmung und zum besseren Verständnis des Untersuchungshintergrundes werden die Initiativen der in Deutschland bildungspolitisch Verantwortlichen beschrieben und an der Bildungssituation der früheren Bundesrepublik und des wiedervereinigten Deutschlands ab 1990 gespiegelt. Ein wesentlicher Bestandteil dieser Arbeit ist es, die Genese der Bildungsökonomie, ihre wichtigsten Aussagen und mathematischen Modelle zu skizzieren. Außerdem werden die in der Literatur schon veröffentlichten wichtigsten statistischen Ergebnisse, z. B. über Kosten und Renditen von Bildungs- und Forschungs-investitionen, wiedergegeben. Im Ergebnisteil dieser Dissertation werden die Interdependenzen der Bildungs-, Forschungs- und Entwicklungsausgaben u. a. mit den Schul- und Studienabschlüssen und dem Bruttoinlandsprodukt mit Hilfe der Zeitreihenanalyse untersucht. Bei kointegrierten Variablen werden die Schätzungen einer Fehlerkorrekturrechnung unterzogen, um eine Scheinregression zu vermeiden. Die Interdependenz der Variablen im Sinne der Humankapitaltheorie wird bestätigt; allerdings zeigen die Schätzgleichungen unterschiedlich große Ergebnisse bzgl. der Bestimmtheitsmaße.The primary objective of this thesis is to provide proof for the central hypothesis of Human Capital Theory, that investment in education, research and development generates an increase in output for society and for the individual. Analysis will be made on the basis of long time series for Germany by making use of cliometric and econometric methods. The findings will then be thoroughly discussed and critically compared. To begin with, and to give a better understanding of the issue the initiatives of the educational-policy-makers will be described and put into relation to the educational situation in former West Germany and reunited Germany since 1990. The main aspect of this piece of research is to outline the genesis of economics of education, its core statements and underlying mathematical models. Furthermore, important statistical data which has already been published regarding (for example) the costs and return of investments in education, research and development will be presented. In the conclusion of this thesis, the interdependences of spending in education, research and development with inter alia graduation and gross domestic product (GDP) will be analysed by the means of time series analysis. When variables are cointegrated, estimates will be subjected to an estimate correction in order to avoid a spurious regression. The interdependency of the variables in the Human Capital Theory is affirmed, although the estimating equations give different results for the coefficients of determination.
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Fredericks, E. "Conservation laws and their associated symmetries for stochastic differential equations." Thesis, 2009. http://hdl.handle.net/10539/6980.
Full textAbstract:
The modelling power of Itˆo integrals has a far reaching impact on a spectrum of diverse fields. For
example, in mathematics of finance, its use has given insights into the relationship between call options
and their non-deterministic underlying stock prices; in the study of blood clotting dynamics, its utility
has helped provide an understanding of the behaviour of platelets in the blood stream; and in the investigation
of experimental psychology, it has been used to build random fluctuations into deterministic
models which model the dynamics of repetitive movements in humans.
Finding the quadrature for these integrals using continuous groups or Lie groups has to take families
of time indexed random variables, known as Wiener processes, into consideration. Adaptations of Sophus
Lie’s work to stochastic ordinary differential equations (SODEs) have been done by Gaeta and Quintero
[1], Wafo Soh and Mahomed [2], ¨Unal [3], Meleshko et al. [4], Fredericks and Mahomed [5], and Fredericks
and Mahomed [6]. The seminal work [1] was extended in Gaeta [7]; the differential methodology of [2]
and [3] were reconciled in [5]; and the integral methodology of [4] was corrected and reconciled in [5] via [6].
Symmetries of SODEs are analysed. This work focuses on maintaining the properties of the Weiner
processes after the application of infinitesimal transformations. The determining equations for first-order
SODEs are derived in an Itˆo calculus context. These determining equations are non-stochastic.
Many methods of deriving Lie point-symmetries for Itˆo SODEs have surfaced. In the Itˆo calculus context
both the formal and intuitive understanding of how to construct these symmetries has led to seemingly
disparate results. The impact of Lie point-symmetries on the stock market, population growth and
weather SODE models, for example, will not be understood until these different results are reconciled as
has been attempted here.
Extending the symmetry generator to include the infinitesimal transformation of the Wiener process
for Itˆo stochastic differential equations (SDEs), has successfully been done in this thesis. The impact of
this work leads to an intuitive understanding of the random time change formulae in the context of Lie
point symmetries without having to consult much of the intense Itˆo calculus theory needed to derive it
formerly (see Øksendal [8, 9]). Symmetries of nth-order SODEs are studied. The determining equations of
these SODEs are derived in an Itˆo calculus context. These determining equations are not stochastic in nature.
SODEs of this nature are normally used to model nature (e.g. earthquakes) or for testing the safety
and reliability of models in construction engineering when looking at the impact of random perturbations. The symmetries of high-order multi-dimensional SODEs are found using form invariance arguments on
both the instantaneous drift and diffusion properties of the SODEs. We then apply this to a generalised
approximation analysis algorithm. The determining equations of SODEs are derived in an It¨o calculus
context.
A methodology for constructing conserved quantities with Lie symmetry infinitesimals in an Itˆo integral
context is pursued as well. The basis of this construction relies on Lie bracket relations on both the
instantaneous drift and diffusion operators.
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Rached, Nadhir B. "Hybrid Adaptive Multilevel Monte Carlo Algorithm for Non-Smooth Observables of Itô Stochastic Differential Equations." Thesis, 2013. http://hdl.handle.net/10754/306490.
Full textAbstract:
The Monte Carlo forward Euler method with uniform time stepping is the standard technique to compute an approximation of the expected payoff of a solution of an Itô SDE. For a given accuracy requirement TOL, the complexity of this technique for well behaved problems, that is the amount of computational work to solve the problem, is O(TOL-3).
A new hybrid adaptive Monte Carlo forward Euler algorithm for SDEs with non-smooth coefficients and low regular observables is developed in this thesis. This adaptive method is based on the derivation of a new error expansion with computable leading-order terms. The basic idea of the new expansion is the use of a mixture of prior information to determine the weight functions and posterior information to compute the local error. In a number of numerical examples the superior efficiency of the hybrid adaptive algorithm over the standard uniform time stepping technique is verified. When a non-smooth binary payoff with either GBM or drift singularity type of SDEs is considered, the new adaptive method achieves the same complexity as the uniform discretization with smooth problems. Moreover, the new developed algorithm is extended to the MLMC forward Euler setting which reduces the complexity from O(TOL-3) to O(TOL-2(log(TOL))2). For the binary option case with the same type of Itô SDEs, the hybrid adaptive MLMC forward Euler recovers the standard multilevel computational cost O(TOL-2(log(TOL))2). When considering a higher order Milstein scheme, a similar complexity result was obtained by Giles using the uniform time stepping for one dimensional SDEs. The difficulty to extend Giles' Milstein MLMC method to the multidimensional case is an argument for the flexibility of our new constructed adaptive MLMC forward Euler method which can be easily adapted to this setting. Similarly, the expected complexity O(TOL-2(log(TOL))2) is reached for the multidimensional case and verified numerically.
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Foster, Stephanie Ann. "Parametric equations : an investigation into ladder applications." Thesis, 2011. http://hdl.handle.net/2152/ETD-UT-2011-08-3800.
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Parametric equations are used to represent the pathway of an object in terms of time or another changing variable. This allows, for example, for equations that are written using two variables to be examined in terms of the passage of time. In this paper the author examines two traditional application problems whose solutions can be enriched through the use of parametric equations. In the first, the falling ladder problem, a ladder is leaned against a wall then pulled away with a constant velocity. Deriving parametric equations for this scenario permits the pathway of the ladder to be plotted. Parametric equations also make it possible for the horizontal and vertical velocities of the ladder to be examined separately. The second problem is that of maximizing the length of a ladder that can fit around a hallway corner. In this problem an envelope algorithm is first developed, then parametrized to further investigate this scenario. Using these two situations, this report ultimately shows how parametric equations can be used to give a more thorough approach to some of today’s most classic calculus problems.text
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Kao, Chien-Yu, and 高千渝. "Investigation into nanowire coupling efficiency through the simulation of Maxwell’s equation." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/66829970091185562468.
Full textAbstract:
碩士國立臺灣大學
工程科學及海洋工程學研究所
104
An explicit finite-difference scheme for solving the three-dimensional Maxwell’s equations in staggered grids is presented in time domain. The aim of this thesis is to solve the Faraday’s and Amp`ere’s equations in time domain within the discrete zero-divergence context for the electric and magnetic fields (or Gauss’s law). The local conservation laws in Maxwell’s equations are also numerically preserved all the time using proposed the explicit second-order accurate symplectic partitioned Runge-Kutta temporal scheme. Following the method of lines, the spatial derivative terms in the semi-discretized Faraday’s and Amp`ere’s equations are then properly discretized to get a phase very accurate solution. To achieve the goal of getting the best dispersive characteristics, this centered scheme minimizes the difference between the exact and numerical phase velocities. The significant dispersion and anisotropy errors manifested normally in finite difference time domain methods are therefore much reduced. The dual-preserving (symplecticity and dispersion relation equation) solver is numerically demonstrated to be efficient for use to get in particular a long-term accurate Maxwell’s solution. By applying the developed FDTD scheme, we aim to study the wave propagation issue on nanowires. The efficency of evanescent coupling between two air-clad silica nanowires with diameter D = 350nm in HE11 single-mode operation is addressed. In the overlapping region, we can see that the electric, magnetic and poynting fields vary between two nanowires by cutting 2D-planes and 1D-Y-axis with different a streamwise positions. From the property of conservation of energy of Poynting theory, we confirm the validity of the propoesd finite difference method. Based on the computed 3D result of solving the Maxwell’s equations, we can clearly predict not only the streamlines of eletric and magnetic fields of HE11 mode in two nanowires but can also reveal the streaklines of them in the overlapping region.
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Yao, Chin-Yuan, and 姚智元. "The use of structural equation modeling control mechanisms into RFID system reliability." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/53851468230469336613.
Full textAbstract:
碩士國立勤益科技大學
工業工程與管理系
98
In the global competition environment, enterprise faces with many kinds of challenge. To maintain the enterprise’s competition in the market, constantly improving internal /external efficiency of entire supply chain is the major issue. There are many enterprises who have launched the RFID applications in their supply chain management, and these enterprises have had successfully improved the efficiency of supply chain. Therefore, to retain the reliability of complicated RFID system and the system security are the most problems need to be address. RFID system consists of tags, antennas, readers, middleware and computer application systems, this research will rearrange the above components to three major subsystems, hardware, software, and remote monitoring subsystem. The components of each subsystem will be defined for further reliability study. The failure rate of each component will be obtained thru elaborative lab experiments, and recorded. With the method of Structural equation model (SEM), the key subsystem of RFID system which affects the total reliability will be identified. Through regression analysis, the results of research will provide a clear for future research and enterprises who wish to verify the reliability of RFID application system Keywords: RFID, reliability, structural equation modeling.
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Ting, Yu Kai, and 丁於楷. "New Physical Insight into the Fluid Dynamics of Lorenz Equations." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/wvktrb.
Full textAbstract:
碩士國立清華大學
動力機械工程學系
103
New physical insight into the variables and parameters of nonlinear Lorenz equations are discussed in this work. In 1963, the equations are derived from the model of natural convection by Lorenz and are noted for chaotic motion. The chaos means system has an irregular motion, and is sensitive to initial conditions. The Lorenz equations have been studied in many papers, which are focus on the stability and the chaotic dynamics. However, the physical implication comparing the Lorenz equations with natural convection attracts little attention in past literatures. Therefore, first step is to derive the Lorenz equations which are ordinary differential equations from the original partial differential equations of natural convection, including assumptions, the derivation, and the simulation results. Then, derive the Lorenz equations again with different forced conditions, which are viscosity, buoyancy, and diffusion. With respect to the simulations of the modified Lorenz equations, observe the relation between the variables and the forced conditions. At last, due to the nonlinear passivity theory and known physical implication, propose the physical insight into the variables and parameters of the Lorenz equations. The study propose that the variables of Lorenz equations, x, y, z, are kinetic energy, thermodynamic potential energy, and total energy respectively. Use kinds of method or theory to prove it. Moreover, it’s better to verify the insight by experiment in the future. Expect that the analysis method applies to the known chaotic systems.
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楊仕榮. "The study of game integration into mathematical equations for supplementary teaching." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/78206346127085437909.
Full text
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He, Jie, and 何潔. "The Research of the Computer Programming into the Game Associate with the Linear Equation." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/35467576855665304308.
Full textAbstract:
碩士中原大學
應用數學研究所
101
In this research program, we investigate the common cup-turning problem. First, we make the flow chart of the (cup-turning) process. Secondly, we transfer the problem into computer games with the help of programming language. It helps students to understand the mathematical problems behind the cup-turning process when they are playing the game.