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Dissertations / Theses on the topic 'Time dependent covariate methods'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 February 2022

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1

Chen, I.-Chen. "Improved Methods and Selecting Classification Types for Time-Dependent Covariates in the Marginal Analysis of Longitudinal Data." UKnowledge, 2018. https://uknowledge.uky.edu/epb_etds/19.

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Generalized estimating equations (GEE) are popularly utilized for the marginal analysis of longitudinal data. In order to obtain consistent regression parameter estimates, these estimating equations must be unbiased. However, when certain types of time-dependent covariates are presented, these equations can be biased unless an independence working correlation structure is employed. Moreover, in this case regression parameter estimation can be very inefficient because not all valid moment conditions are incorporated within the corresponding estimating equations. Therefore, approaches using the

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2

Xie, Xiangwen. "Covariate measurement error methods in failure time regression /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/9538.

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3

Heltshe, Sonya Lenore. "Quantification of length-bias in screening trials with covariate-dependent test sensitivity /." Connect to full text via ProQuest. Limited to UCD Anschutz Medical Campus, 2007.

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Thesis (Ph.D. in Biostatistics, Department of Preventive Medicine and Biometrics) -- University of Colorado Denver, 2007.<br>Typescript. Includes bibliographical references (leaves 89-93). Free to UCD affiliates. Online version available via ProQuest Digital Dissertations;

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4

Yang, Feng Wei. "Multigrid solution methods for nonlinear time-dependent systems." Thesis, University of Leeds, 2014. http://etheses.whiterose.ac.uk/7579/.

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An efficient, accurate and reliable numerical solver is essential for solving complex mathematical models and obtaining their computational approximations. The solver presented in this work is built upon nonlinear multigrid with the full approximation scheme (FAS). Its implementation is achieved, in part, using a complex, open source software library PARAMESH, and the resulting numerical solver, Campfire, also combines with adaptive mesh refinement, adaptive time stepping and parallelization through domain decomposition. There are five mathematical models considered in this work, ranging from

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5

Xie, Xiaoliang. "Large time-stepping methods for higher order time-dependent evolution equations." [Ames, Iowa : Iowa State University], 2008.

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6

Djidjeli, Kamel. "Numerical methods for some time-dependent partial differential equations." Thesis, Brunel University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293104.

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7

Halstead, David Michael. "Time dependent quantum methods applied to molecule-surface interactions." Thesis, University of Liverpool, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303642.

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8

Manrique, Garcia Aurora. "Econometric analysis of limited dependent time series." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389797.

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9

Kim, Junkyoung. "Complex seismic sources and time-dependent moment tensor inversion." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184841.

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There are many examples of earthquakes whose surface expressions are much more complicated than the seismologically derived faulting models. Seismologists also have found seismic source complexity and improved seismicity data have shown that rupture may occur on irregular or multiple shear surfaces. To simultaneously map both geometrical and temporal variation of the seismic sources for a complex rupture history from observed seismograms, it is possible to use a time dependent moment tensor (TDMT) inversion. The TDMT inversion algorithm has been tested with three synthetic data examples with v

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10

Shafik, Nivien [Verfasser]. "Modeling Time-Dependent Economic Data by Boosting Methods / Nivien Shafik." Norderstedt : Books on Demand, 2012. http://d-nb.info/1021516821/34.

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11

Gao, Liping. "Splitting finite difference methods for the time-dependent Maxwell equations." Thesis, Coventry University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.429698.

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12

Lolla, Sri Venkata Tapovan. "Path planning in time dependent flows using level set methods." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/78212.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Cataloged from student-submitted PDF version of thesis.<br>Includes bibliographical references (p. 167-177).<br>Autonomous underwater vehicles such as gliders have emerged as valuable scientific platforms due to their increasing uses in several oceanic applications, ranging from security, acoustic surveillance and military reconnaissance to collection

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13

Akman, Tugba. "Discontinuous Galerkin Methods For Time-dependent Convection Dominated Optimal Control Problems." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613394/index.pdf.

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Distributed optimal control problems with transient convection dominated diffusion convection reaction equations are considered. The problem is discretized in space by using three types of discontinuous Galerkin (DG) method: symmetric interior penalty Galerkin (SIPG), nonsymmetric interior penalty Galerkin (NIPG), incomplete interior penalty Galerkin (IIPG). For time discretization, Crank-Nicolson and backward Euler methods are used. The discretize-then-optimize approach is used to obtain the finite dimensional problem. For one-dimensional unconstrained problem, Newton-Conjugate Gradient metho

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14

Omosigho, S. E. "Approximate methods for single-server queues with time dependent arrival rate." Thesis, Lancaster University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332627.

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15

Rouf, Hasan. "Unconditionally stable finite difference time domain methods for frequency dependent media." Thesis, University of Manchester, 2010. https://www.research.manchester.ac.uk/portal/en/theses/unconditionally-stable-finite-difference-time-domain-methods-for-frequency-dependent-media(50e4adf1-d1e4-4ad2-ab2d-70188fb8b7b6).html.

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The efficiency of the conventional, explicit finite difference time domain (FDTD)method is constrained by the upper limit on the temporal discretization, imposed by the Courant–Friedrich–Lewy (CFL) stability condition. Therefore, there is a growing interest in overcoming this limitation by employing unconditionally stable FDTD methods for which time-step and space-step can be independently chosen. Unconditionally stable Crank Nicolson method has not been widely used in time domain electromagnetics despite its high accuracy and low anisotropy. There has been no work on the Crank Nicolson FDTD (

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16

Zhao, Jun. "Analysis of finite element approximation and iterative methods for time-dependent Maxwell problems." Texas A&M University, 2002. http://hdl.handle.net/1969/582.

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17

Liu, Ke. "A joint model of an internal time-dependent covariate and bivariate time-to-event data with an application to muscular dystrophy surveillance, tracking and research network data." Diss., University of Iowa, 2015. https://ir.uiowa.edu/etd/2237.

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Joint modeling of a single event time response with a longitudinal covariate dates back to the 1990s. The three basic types of joint modeling formulations are selection models, pattern mixture models and shared parameter models. The shared parameter models are most widely used. One type of a shared parameter model (Joint Model I) utilizes unobserved random effects to jointly model a longitudinal sub-model and a survival sub-model to assess the impact of an internal time-dependent covariate on the time-to-event response. Motivated by the Muscular Dystrophy Surveillance, Tracking and Research Ne

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18

Johansson, August. "Duality-based adaptive finite element methods with application to time-dependent problems." Doctoral thesis, Umeå : Institutionen för matematik och matematisk statistik, Umeå universitet, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-33872.

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19

Szady, Michael Joseph. "Finite element methods for the time dependent simulation of viscoelastic fluid flows." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10914.

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20

Fathe, Jalali Atabak, and Hugo Åkesson. "Comparing Three Numerical Methods For Solving The 1D Time Dependent Schrödinger Equation." Thesis, KTH, Skolan för teknikvetenskap (SCI), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-297532.

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The purpose of this thesis is to implement three numerical methods for solving and examining the time-dependent Schrödinger equation (TDSE) of the analytically solved quantum harmonic oscillator (QHO) and the, to our knowledge, analytically unsolved double well potential (DW), and to compare the numerical solutions. These methods are the Crank-Nicolson method and two split operator methods of different orders. For the QHO, the exact solution is used to determine the errors of the methods, while other methods for examining the DW had to be used (due to the lack of exact solutions). The solution

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21

Olbrant, Edgar [Verfasser]. "Models and numerical methods for time- and energy-dependent particle transport / Edgar Olbrant." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2012. http://d-nb.info/1023980002/34.

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22

Sautter, Jörg-Matthias. "Discrete projection methods for time dependent incompressible fluid flow simulations in arbitrary domains." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=971751307.

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23

Nawas, Zain. "Performance of Adaptive Fast Multipole Methods In Three Dimensions For Time-Dependent Problem." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-434772.

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In the last two decades, physical constraints in chip design have spawned a paradigm shift in computer architecture. The availability of multi-core threaded systems has increased the parallel execution which has provided an opportunity for analysing computationallydemanding problems. The N-Body problem is a fundamental problem in the field of computational science and in this project, we havereviewed one of the N-body algorithms named the Fast Multipole Methods(FMM). The implementation of FMM is pretty complex and is dependent on multiple subroutines and in each subroutine, communication, and

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24

Hankel, Marlies. "Time-dependent wavepacket methods for the calculation of state-to-state molecular reactive cross sections." Thesis, University of Bristol, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391180.

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25

Kopylov, Nikita. "Magnus-based geometric integrators for dynamical systems with time-dependent potentials." Doctoral thesis, Universitat Politècnica de València, 2019. http://hdl.handle.net/10251/118798.

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[ES] Esta tesis trata sobre la integración numérica de sistemas hamiltonianos con potenciales explícitamente dependientes del tiempo. Los problemas de este tipo son comunes en la física matemática, porque provienen de la mecánica cuántica, clásica y celestial. La meta de la tesis es construir integradores para unos problemas relevantes no autónomos: la ecuación de Schrödinger, que es el fundamento de la mecánica cuántica; las ecuaciones de Hill y de onda, que describen sistemas oscilatorios; el problema de Kepler con la masa variante en el tiempo. El Capítulo 1 describe la motivación y los o

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26

Kuhn, Alexander [Verfasser], and Holger [Akademischer Betreuer] Theisel. "Lagrangian methods for visualization and analysis of time-dependent vector fields / Alexander Kuhn. Betreuer: Holger Theisel." Magdeburg : Universitätsbibliothek, 2013. http://d-nb.info/1054421293/34.

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27

Kuhn, Alexander Verfasser], and Holger [Akademischer Betreuer] [Theisel. "Lagrangian methods for visualization and analysis of time-dependent vector fields / Alexander Kuhn. Betreuer: Holger Theisel." Magdeburg : Universitätsbibliothek, 2013. http://nbn-resolving.de/urn:nbn:de:gbv:ma9:1-4177.

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28

Bui, Tang Bao Ngoc. "Semi-linear waves with time-dependent speed and dissipation." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2014. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-147037.

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The main goal of our thesis is to understand qualitative properties of solutions to the Cauchy problem for the semi-linear wave model with time-dependent speed and dissipation. We greatly benefited from very precise estimates for the corresponding linear problem in order to obtain the global existence (in time) of small data solutions. This reason motivated us to introduce very carefully a complete description for classification of our models: scattering, non-effective, effective, over-damping. We have considered those separately.

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29

Kim, Junhan, Daniel P. Marrone, Chi-Kwan Chan, Lia Medeiros, Feryal Özel, and Dimitrios Psaltis. "BAYESIAN TECHNIQUES FOR COMPARING TIME-DEPENDENT GRMHD SIMULATIONS TO VARIABLE EVENT HORIZON TELESCOPE OBSERVATIONS." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/622523.

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The Event Horizon Telescope (EHT) is a millimeter-wavelength, very-long-baseline interferometry (VLBI) experiment that is capable of observing black holes with horizon-scale resolution. Early observations have revealed variable horizon-scale emission in the Galactic Center black hole, Sagittarius. A* (Sgr A*). Comparing such observations to time-dependent general relativistic magnetohydrodynamic (GRMHD) simulations requires statistical tools that explicitly consider the variability in both the data and the models. We develop here a Bayesian method to compare time-resolved simulation images to

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30

Carreño, Sánchez Amanda María. "Integration methods for the time dependent neutron diffusion equation and other approximations of the neutron transport equation." Doctoral thesis, Universitat Politècnica de València, 2020. http://hdl.handle.net/10251/144771.

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[ES] Uno de los objetivos más importantes en el análisis de la seguridad en el campo de la ingeniería nuclear es el cálculo, rápido y preciso, de la evolución de la potencia dentro del núcleo del reactor. La distribución de los neutrones se puede describir a través de la ecuación de transporte de Boltzmann. La solución de esta ecuación no puede obtenerse de manera sencilla para reactores realistas, y es por ello que se tienen que considerar aproximaciones numéricas. En primer lugar, esta tesis se centra en obtener la solución para varios problemas estáticos asociados con la ecuación de difu

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31

Galata, Salvatore. "A time dependent search for neutrino emission from microquasars with the ANTARES telescope." Phd thesis, Aix-Marseille Université, 2012. http://tel.archives-ouvertes.fr/tel-00782883.

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La Collaboration ANTARES exploite actuellement un détecteur sous-marin Cherenkov d édi é a l'astronomie neutrino de haute énergie. Le but principal de cette expérience est de d détecter les sources cosmiques de neutrinos, a n de r ev eler les sites de production des rayons cosmiques. Parmi les sources candidates gurent celles o u a lieu l'acc el eration de ces rayons cosmiques dans les jets relativistes, comme les noyaux actifs de galaxie, les sursauts gamma et les microquasars. Les microquasars sont des syst émes stellaires binaires form es par un objet compact accr étant la mati ere d'une ét

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32

Lilienthal, Martin [Verfasser], Thomas [Akademischer Betreuer] Weiland, and Herbert [Akademischer Betreuer] Egger. "Error Controlled hp-Adaptive Finite Element Methods for the Time-Dependent Maxwell Equations / Martin Lilienthal. Betreuer: Thomas Weiland ; Herbert Egger." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2015. http://d-nb.info/111190992X/34.

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33

Önskog, Thomas. "The Skorohod problem and weak approximation of stochastic differential equations in time-dependent domains." Doctoral thesis, Umeå universitet, Institutionen för matematik och matematisk statistik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-25429.

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This thesis consists of a summary and four scientific articles. All four articles consider various aspects of stochastic differential equations and the purpose of the summary is to provide an introduction to this subject and to supply the notions required in order to fully understand the articles. In the first article we conduct a thorough study of the multi-dimensional Skorohod problem in time-dependent domains. In particular we prove the existence of cádlág solutions to the Skorohod problem with oblique reflection in time-independent domains with corners. We use this existence result to cons

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34

Geiger, Daniel [Verfasser]. "Particles on surfaces: development and application of Atomic Force Microscopy methods to study time dependent adhesion of nano particles / Daniel Geiger." Ulm : Universität Ulm, 2018. http://d-nb.info/116253995X/34.

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35

Schnücke, Gero [Verfasser], Christian [Gutachter] Klingenberg, and Manfred [Gutachter] Dobrowolski. "Arbitrary Lagrangian-Eulerian Discontinous Galerkin methods for nonlinear time-dependent first order partial differential equations / Gero Schnücke ; Gutachter: Christian Klingenberg, Manfred Dobrowolski." Würzburg : Universität Würzburg, 2016. http://d-nb.info/1117477290/34.

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36

Mhana, Najwa. "Geothermal Methods : application of time-dependent tomography to detect changes in structure at Long Valley caldera and the Coso geothermal area, California." Thesis, Durham University, 2016. http://etheses.dur.ac.uk/12078/.

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Structural changes in active volcanic and producing geothermal systems are expected because of changes in the distribution of fluids, gases and cracks in the host rocks. Such changes have traditionally been studied using seismic tomography where two independent inversion results are differenced. A new tomography program tomo4d, inverts two epochs simultaneously, imposing constraints to minimize the structural differences calculated between different epochs. This method suppresses spurious changes not required by the data. Both methods were applied to data from Long Valley caldera and the Coso

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37

Deng, Yingjun. "Degradation modeling based on a time-dependent Ornstein-Uhlenbeck process and prognosis of system failures." Thesis, Troyes, 2015. http://www.theses.fr/2015TROY0004/document.

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Cette thèse est consacrée à la description, la prédiction et la prévention des défaillances de systèmes. Elle se compose de quatre parties relatives à la modélisation stochastique de dégradation, au pronostic de défaillance du système, à l'estimation du niveau de défaillance et à l'optimisation de maintenance.Le processus d'Ornstein-Uhlenbeck (OU) dépendant du temps est introduit dans un objectif de modélisation des dégradations. Sur la base de ce processus, le premier instant de passage d’un niveau de défaillance prédéfini est considéré comme l’instant de défaillance du système considéré. Dif

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38

Kieri, Emil. "Numerical Methods for Wave Propagation : Analysis and Applications in Quantum Dynamics." Doctoral thesis, Uppsala universitet, Avdelningen för beräkningsvetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-268625.

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We study numerical methods for time-dependent partial differential equations describing wave propagation, primarily applied to problems in quantum dynamics governed by the time-dependent Schrödinger equation (TDSE). We consider both methods for spatial approximation and for time stepping. In most settings, numerical solution of the TDSE is more challenging than solving a hyperbolic wave equation. This is mainly because the dispersion relation of the TDSE makes it very sensitive to dispersion error, and infers a stringent time step restriction for standard explicit time stepping schemes. The TD

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39

Falklöf, Olle, and Bo Durbeej. "Modeling of phytochrome absorption spectra." Linköpings universitet, Beräkningsfysik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-92393.

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Phytochromes constitute one of the six well-characterized families of photosensory proteins in Nature. From the viewpoint of computational modeling, however, phytochromes have been the subject of much fewer studies than most other families of photosensory proteins, which is likely a consequence of relevant high-resolution structural data becoming available only in recent years. In this work, hybrid quantum mechanics/molecular mechanics (QM/MM) methods are used to calculate UV-vis absorption spectra of Deinococcus radiodurans bacteriophytochrome. We investigate how the choice of QM/MM methodolo

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40

Zhu, Weiqi, and ycqq929@gmail com. "An Investigation into Reliability Based Methods to Include Risk of Failure in Life Cycle Cost Analysis of Reinforced Concrete Bridge Rehabilitation." RMIT University. Civil, Environmental and Chemical Engineering, 2008. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080822.140447.

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Reliability based life cycle cost analysis is becoming an important consideration for decision-making in relation to bridge design, maintenance and rehabilitation. An optimal solution should ensure reliability during service life while minimizing the life cycle cost. Risk of failure is an important component in whole of life cycle cost for both new and existing structures. Research work presented here aimed to develop a methodology for evaluation of the risk of failure of reinforced concrete bridges to assist in decision making on rehabilitation. Methodology proposed here combines fault t

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41

Dittmann, Niklas [Verfasser], Nicole Akademischer Betreuer] Helbig, Janine [Akademischer Betreuer] Splettstößer, and Volker [Akademischer Betreuer] [Meden. "Dynamics and fluctuations in single-electron tunneling devices : analytical and numerical methods for time-dependent quantum transport in interacting nanosystems / Niklas Dittmann ; Nicole Helbig, Janine Splettstößer, Volker Meden." Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/1189672197/34.

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Singh, Pranav. "High accuracy computational methods for the semiclassical Schrödinger equation." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/274913.

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The computation of Schrödinger equations in the semiclassical regime presents several enduring challenges due to the presence of the small semiclassical parameter. Standard approaches for solving these equations commence with spatial discretisation followed by exponentiation of the discretised Hamiltonian via exponential splittings. In this thesis we follow an alternative strategy${-}$we develop a new technique, called the symmetric Zassenhaus splitting procedure, which involves directly splitting the exponential of the undiscretised Hamiltonian. This technique allows us to design methods tha

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43

Carter-Fenk, Kevin D. "Design and Implementation of Quantum Chemistry Methods for the Condensed Phase: Noncovalent Interactions at the Nanoscale and Excited States in Bulk Solution." The Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu161617640330551.

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González, Pintor Sebastián. "Approximation of the Neutron Diffusion Equation on Hexagonal Geometries." Doctoral thesis, Universitat Politècnica de València, 2012. http://hdl.handle.net/10251/17829.

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La ecuación de la difusión neutrónica describe la población de neutrones de un reactor nuclear. Este trabajo trata con este modelo para reactores nucleares con geometría hexagonal. En primer lugar se estudia la ecuación de la difusión neutrónica. Este es un problema diferencial de valores propios, llamado problema de los modos Lambda. Para resolver el problema de los modos Lambda se han comparado diferentes métodos en geometrías unidimensionales, resultando como el mejor el método de elementos espectrales. Usando este método discretizamos los operadores en geometrías bidimensiones y tridimensi

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45

Scheid, Philippe. "Investigation of light–induced ultrafast magnetization dynamics using ab initio methods." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0166.

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Cette thèse commence par une revue de l’état actuel de l’expérimentation et de la théorie liées à la désaimantation ultrarapide induite par de la lumière, ainsi qu'au retournement tout optique dépendant de l'hélicité. Ceci est suivi d’un aperçu de la théorie de la fonctionnelle de la densité, sur laquelle repose la plupart des travaux rapportés par la suite. La première partie des résultats concerne l’étude de l’effet d’une élévation de la température électronique sur les propriétés de la matière aimantée, et plus précisément Ni, Co, Fe et FePt. Nous montrons que le moment magnétique de chaque

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Sinha, Roy Rajarshi. "Ab initio simulation of optical properties of noble-metal clusters." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0017/document.

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L'intérêt de la recherche fondamentale pour les morceaux nanométriques de métaux nobles est principalement dû à la résonance localisée des plasmons de surface (LSPR) dans l'absorption optique. Différents aspects, liés à la compréhension théorique de la LSPR dans le cas de clusters de métaux nobles de taille dite intermédiaire, sont étudiés dans ce manuscrit. Afin d'avoir une vision plus large nous utilisons deux approches : l'approche électromagnétique classique et le formalisme ab initio en temps réel de la théorie de la fonctionnelle de la densité dépendant du temps (RT-TDDFT). Une comparais

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47

Babykina, Evgénia. "Modélisation statistique d'événements récurrents. Exploration empirique des estimateurs, prise en compte d'une covariable temporelle et application aux défaillances des réseaux d'eau." Thesis, Bordeaux 2, 2010. http://www.theses.fr/2010BOR21750/document.

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Dans le contexte de la modélisation aléatoire des événements récurrents, un modèle statistique particulier est exploré. Ce modèle est fondé sur la théorie des processus de comptage et est construit dans le cadre d'analyse de défaillances dans les réseaux d'eau. Dans ce domaine nous disposons de données sur de nombreux systèmes observés durant une certaine période de temps. Les systèmes étant posés à des instants différents, leur âge est utilisé en tant qu'échelle temporelle dans la modélisation. Le modèle tient compte de l'historique incomplet d'événements, du vieillissement des systèmes, de l

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Raminelli, Jaqueline Aparecida. "Métodos de adequação e diagnóstico em modelos de sobrevivência dinâmicos." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11134/tde-03052016-164950/.

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A análise de dados de sobrevivência tem sido tradicionalmente baseada no modelo de regressão de Cox (COX, 1972). No entanto, a suposição de taxas de falha proporcionais assumida para esse modelo pode não ser atendida em diversas situações práticas. Essa restrição do modelo de Cox tem gerado interesse em abordagens alternativas, dentre elas os modelos dinâmicos que permitem efeito das covariáveis variando no tempo. Neste trabalho, foram revisados os principais modelos de sobrevivência dinâmicos com estrutura aditiva e multiplicativa nos contextos não paramétrico e semiparamétrico. Métodos gráfi

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Hunter, Brandon. "Channel Probing for an Indoor Wireless Communications Channel." BYU ScholarsArchive, 2003. https://scholarsarchive.byu.edu/etd/64.

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The statistics of the amplitude, time and angle of arrival of multipaths in an indoor environment are all necessary components of multipath models used to simulate the performance of spatial diversity in receive antenna configurations. The model presented by Saleh and Valenzuela, was added to by Spencer et. al., and included all three of these parameters for a 7 GHz channel. A system was built to measure these multipath parameters at 2.4 GHz for multiple locations in an indoor environment. Another system was built to measure the angle of transmission for a 6 GHz channel. The addition of th

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Chen, An-peng, and 陳安朋. "Ordered Bivariate Survival Time with Time Dependent Covariate -Comparison of Marginal Method." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/43222875865409794332.

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碩士<br>國立中央大學<br>統計研究所<br>95<br>The Department of Health in Taiwan began to freely provide the treatment of HAART (highly active antiretroviral therapy) for the AIDS patients in the appointed hospitals all over the country ever since April, 1997 and up to now, reach a decade period. We are interested in the different effects of HAART to the 136 AIDS patients before and after the onset of AIDS. To investigate this research problem, we focus on three marginal approaches, the AG (Andersen and Gill, 1982) model, WLW (Wei, Lin, and Wiessfeld, 1989) model and PWP (Prentice, Williams and Petersen, 198

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