Дисертації з теми "Time eigenvalue"
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-25 дисертацій для дослідження на тему "Time eigenvalue".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте дисертації для різних дисциплін та оформлюйте правильно вашу бібліографію.
Hollman, Jorge. "Step by step eigenvalue analysis with EMTP discrete time solutions." Thesis, University of British Columbia, 2006. http://hdl.handle.net/2429/67.
Повний текст джерелаAshokkumar, C. R. "Eigenvalue/eigenvector perturbation for time response analysis of linear uncertain systems /." The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487858417983696.
Повний текст джерелаNdow, G. L. "Euclidean-time formulation of the eigenvalue moment method for finite dimensional systems." DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 1992. http://digitalcommons.auctr.edu/dissertations/3767.
Повний текст джерелаNadsady, Kenneth Allan. "A two-stage method for system identification from time series." Ohio : Ohio University, 1998. http://www.ohiolink.edu/etd/view.cgi?ohiou1176406389.
Повний текст джерелаCarreño, 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.
Повний текст джерела[CAT] Un dels objectius més importants per a l'anàlisi de la seguretat en el camp de l'enginyeria nuclear és el càlcul, ràpid i precís, de l'evolució de la potència dins del nucli d'un reactor. La distribució dels neutrons pot modelar-se mitjançant l'equació del transport de Boltzmann. La solució d'aquesta equació per a un reactor realístic no pot obtenir's de manera senzilla. És per això que han de considerar-se aproximacions numèriques. En primer lloc, la tesi se centra en l'obtenció de la solució per a diversos problemes estàtics associats amb l'equació de difusió neutrònica: els modes lambda, els modes gamma i els modes alpha. Per a la discretització espacial s'ha utilitzat un mètode d'elements finits d'alt ordre. Algunes de les característiques dels problemes espectrals s'analitzaran i es compararan per a diferents reactors. Tanmateix, diversos solucionadors de problemes d'autovalors i estratègies es desenvolupen per a calcular els problemes obtinguts de la discretització espacial. La majoria dels treballs per a resoldre l'equació de difusió neutrònica estan dissenyats per a l'aproximació de dos grups d'energia i sense considerar dispersió de neutrons del grup tèrmic al grup ràpid. El principal avantatge de la metodologia exposada és que no depèn de la geometria del reactor, del tipus de problema d'autovalors ni del nombre de grups d'energia del problema. Seguidament, s'obté la solució de les equacions estacionàries d'harmònics esfèrics. La implementació d'aquestes equacions té dues principals diferències respecte a l'equació de difusió. Primer, la discretització espacial es realitza a nivell de pin a partir de l'estudi de diferents malles. Segon, el nombre de grups d'energia és, generalment, major que dos. D'aquesta forma, es desenvolupen estratègies a blocs per a optimitzar el càlcul dels problemes algebraics associats. Finalment, s'implementa un mètode modal amb actualitzacions dels modes per a integrar l'equació de difusió neutrònica dependent del temps. Es presenten i es comparen els mètodes modals basats en l'expansió dels diferents modes espacials per a diversos tipus de transitoris. A més a més, un control de pas de temps adaptatiu es desenvolupa, evitant l'actualització dels modes d'una manera fixa i adaptant el pas de temps en funció de vàries estimacions de l'error.
[EN] One of the most important targets in nuclear safety analyses is the fast and accurate computation of the power evolution inside of the reactor core. The distribution of neutrons can be described by the neutron transport Boltzmann equation. The solution of this equation for realistic nuclear reactors is not straightforward, and therefore, numerical approximations must be considered. First, the thesis is focused on the attainment of the solution for several steady-state problems associated with neutron diffusion problem: the $\lambda$-modes, the $\gamma$-modes and the $\alpha$-modes problems. A high order finite element method is used for the spatial discretization. Several characteristics of each type of spectral problem are compared and analyzed on different reactors. Thereafter, several eigenvalue solvers and strategies are investigated to compute efficiently the algebraic eigenvalue problems obtained from the discretization. Most works devoted to solve the neutron diffusion equation are made for the approximation of two energy groups and without considering up-scattering. The main property of the proposed methodologies is that they depend on neither the reactor geometry, the type of eigenvalue problem nor the number of energy groups. After that, the solution of the steady-state simplified spherical harmonics equations is obtained. The implementation of these equations has two main differences with respect to the neutron diffusion. First, the spatial discretization is made at level of pin. Thus, different meshes are studied. Second, the number of energy groups is commonly bigger than two. Therefore, block strategies are developed to optimize the computation of the algebraic eigenvalue problems associated. Finally, an updated modal method is implemented to integrate the time-dependent neutron diffusion equation. Modal methods based on the expansion of the different spatial modes are presented and compared in several types of transients. Moreover, an adaptive time-step control is developed that avoids setting the time-step with a fixed value and it is adapted according to several error estimations.
Carreño Sánchez, AM. (2020). Integration methods for the time dependent neutron diffusion equation and other approximations of the neutron transport equation [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/144771
TESIS
Saberian, Aminmohammad. "Applying adjacency based control to distribution networks." Thesis, Queensland University of Technology, 2019. https://eprints.qut.edu.au/126755/1/Aminmohammad_Saberian_Thesis.pdf.
Повний текст джерелаMendez, Barrios César. "Low-Order Controllers for Time-Delay Systems : an Analytical Approach." Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00719477.
Повний текст джерелаBrandman, Jeremy. "A level-set method for solving elliptic eigenvalue problems on hypersurfaces ; and, Finite-time blow-up of L[superscript infty] weak solutions of an aggregation equation." Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1619423481&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
Повний текст джерелаBartholomew, David L. "A method of compensator design for discrete systems which bounds both the closed-loop and compensator eigenvalues." Ohio : Ohio University, 1995. http://www.ohiolink.edu/etd/view.cgi?ohiou1174331262.
Повний текст джерелаOlcer, Fahri Ersel. "Linear time invariant models for integrated flight and rotor control." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/44921.
Повний текст джерелаIbn, Taarit Kaouther. "Contribution à l'identification des systèmes à retards et d'une classe de systèmes hybrides." Phd thesis, Ecole Centrale de Lille, 2010. http://tel.archives-ouvertes.fr/tel-00587336.
Повний текст джерелаLang, Robin [Verfasser], and Timo [Akademischer Betreuer] Weidl. "On the eigenvalues of the non-self-adjoint Robin Laplacian on bounded domains and compact quantum graphs / Robin Lang ; Betreuer: Timo Weidl." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2021. http://d-nb.info/123224189X/34.
Повний текст джерелаPersson, Jonas. "Bandwidth-reduced Linear Models of Non-continuous Power System Components." Doctoral thesis, Stockholm : Electric Power Systems, School of Electrical Engineering, Royal Institute of Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3984.
Повний текст джерелаDobson, William Keith. "Method for Improving the Efficiency of Image Super-Resolution Algorithms Based on Kalman Filters." Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/math_theses/82.
Повний текст джерелаQuinlan, John Mathew. "Investigation of driving mechanisms of combustion instabilities in liquid rocket engines via the dynamic mode decomposition." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54343.
Повний текст джерелаHollman, Jorge Ariel. "Step by step eigenvalue analysis with EMTP discrete time solutions." Thesis, 2006. http://hdl.handle.net/2429/18538.
Повний текст джерелаApplied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
Hsu, Chien-Wei, and 許健偉. "On the Estimation of Eigenvalue Regions for Discrete Multiple Time-Delay Systems with Parametric Perturbations." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/50463901330461529432.
Повний текст джерела正修科技大學
機電工程研究所
96
This thesis addresses the root clustering test problem for discrete perturbed systems subjected to multiple time delays. Two kinds of perturbation are treated:(i) highly structured parametric perturbations and (ii) interval matrices. By means of norm, M-matrix, and matrix measure techniques, we estimate several restricted regions in the complex plane in which all eigenvalues of the mentioned systems are located. And these restricted regions are (i) external region of a disk (ii) internal region of a disk (iii) ring region (iv) half planes (v) horizontal strips (vi) vertical strips (vii) rectangle region. Both the stability and the instability conditions for these systems are also investigated via the proposed schemes. Several numerical examples are given to verify the correctness and demonstrate the applicability of the quantitative results.
Yuh, Liaw Kuei, and 廖桂育. "Estimation of eigenvalue location for uncertain systems & the robustness analysis of time-delay systems." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/86856320098740018578.
Повний текст джерелаYeh, Yu-Rung, and 葉于榮. "(1)Representations of Time Lag by Eigenvalue (2)Study of Induction Time in Nucleation and Stability in Colloids via Time Lag and Mean First Passage Time in Diffusion." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/jzkfm6.
Повний текст джерела國立交通大學
應用化學系碩博士班
99
In this thesis, the eigenvalue and Green’s function representations for the time lag of first and second moments were formulated. The Green’s function mentioned above is the one subject to the boundary conditions on both ends being absorbing. The homogeneous nucleation and the coagulation of colloids were discussed with the help of diffusion. Time lag and mean first passage time were employed to interpret the induction time in nucleation and the stability of colloids. The time lag of the first and of second moments will decrease as a result of the properties of Sturm-Liouville operator. We have derived the kinetic equations of homogeneous nucleation in the discrete number of particle coordinate, followed by solving in the Laplace domain. In this way, time lag, mean first passage time, and their corresponding second moments can be obtained. The formulas were tested in the problem of condensing water vapor. The results show that induction time for vapor condensation decreases with increasing vapor pressure. The stability of colloids is commonly expressed by stability ratio. We attempted to interpret the stability with the viewpoint of diffusion via the parameters, relative time lag and relative mean first passage time. It is indicated that relative mean first passage time matches with stability ratio quite well. The relation between the barrier height and the stability ratio is also discussed by applying the method of steepest descent, to obtain an approximate formula. Furthermore, a linear equation was proposed to calculate the critical coagulation concentration from known parameters.
DI, SALVATORE ANTONIETTA. "Structural breaks in dynamic factor models." Doctoral thesis, 2010. http://hdl.handle.net/11573/438101.
Повний текст джерелаChen, Zuojing. "Efficient Modeling Techniques for Time-Dependent Quantum System with Applications to Carbon Nanotubes." 2010. https://scholarworks.umass.edu/theses/421.
Повний текст джерелаHuang, Boshi, and 黃柏蒔. "The Calculation And Application Of Eigenvalues With Time-Delay System." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/67034729836898754336.
Повний текст джерела義守大學
生物技術與化學工程研究所
100
The phenomenon of time delay and characteristics of the high-level dynamic change which often occurs in the control system of the plant have caused the analysis and design of the control system to become particularly complicated and made it impossible to control effectively. Found in past researches, the PID-deadtime controller is indeed able to have better control for the procedures with time delay. So it has significant advantages compared to the conventional PID controller. Therefore, this thesis further explores issues related to system simulation, stability analysis and controller parameter settings which involved control applications of the PID-deadtime controller for the time delay system. The main contribution is to obtain the important values of the time delay system. The approach is to develop a program to acquire multi-point Pade` approximation of the time delay transfer function e-hs. The approximated characteristic polynomial of the original characteristic function can be obtained by using this rational approximation, and then the root of this characteristic polynomial can be solved as the starting guess value. This value can be used to seek the solution of the original characteristic function and to obtain the eigenvalue of the system. By using this eigenvalue as the interpolation point in the multi-point Pade` approximation, the guess value of the approximated characteristic polynomial and the original system characteristic equation can be obtained repeatedly, then a series of system eigenvalues can be found. Finally, the accuracy of all the eigenvalues in a region of complex plane can be verified by argument principles. According to the solution of this eigenvalue, the stability and the time domain response of the system can be determined. This thesis applied the Pade` approximation of the exponential function e-hs to obtain a guess value of the original characteristic equation and then to obtain the rightmost eigenvalue. The Lamber W function was also used to calculate the rightmost eigenvalue. This thesis uses the differential evolution algorithm to search parameters of the time delay controller to achieve maximum system stability.
Cook, Martin. "A collective field theory approach to the large N spectrum of two matrices." Thesis, 2008. http://hdl.handle.net/10539/4604.
Повний текст джерелаScott, Derek Douglas. "An investigation of parity and time-reversal symmetry breaking in tight-binding lattices." Thesis, 2014. http://hdl.handle.net/1805/6106.
Повний текст джерелаMore than a decade ago, it was shown that non-Hermitian Hamiltonians with combined parity (P) and time-reversal (T ) symmetry exhibit real eigenvalues over a range of parameters. Since then, the field of PT symmetry has seen rapid progress on both the theoretical and experimental fronts. These effective Hamiltonians are excellent candidates for describing open quantum systems with balanced gain and loss. Nature seems to be replete with examples of PT -symmetric systems; in fact, recent experimental investigations have observed the effects of PT symmetry breaking in systems as diverse as coupled mechanical pendula, coupled optical waveguides, and coupled electrical circuits. Recently, PT -symmetric Hamiltonians for tight-binding lattice models have been extensively investigated. Lattice models, in general, have been widely used in physics due to their analytical and numerical tractability. Perhaps one of the best systems for experimentally observing the effects of PT symmetry breaking in a one-dimensional lattice with tunable hopping is an array of evanescently-coupled optical waveguides. The tunneling between adjacent waveguides is tuned by adjusting the width of the barrier between them, and the imaginary part of the local refractive index provides the loss or gain in the respective waveguide. Calculating the time evolution of a wave packet on a lattice is relatively straightforward in the tight-binding model, allowing us to make predictions about the behavior of light propagating down an array of PT -symmetric waveguides. In this thesis, I investigate the the strength of the PT -symmetric phase (the region over which the eigenvalues are purely real) in lattices with a variety of PT - symmetric potentials. In Chapter 1, I begin with a brief review of the postulates of quantum mechanics, followed by an outline of the fundamental principles of PT - symmetric systems. Chapter 2 focuses on one-dimensional uniform lattices with a pair of PT -symmetric impurities in the case of open boundary conditions. I find that the PT phase is algebraically fragile except in the case of closest impurities, where the PT phase remains nonzero. In Chapter 3, I examine the case of periodic boundary conditions in uniform lattices, finding that the PT phase is not only nonzero, but also independent of the impurity spacing on the lattice. In addition, I explore the time evolution of a single-particle wave packet initially localized at a site. I find that in the case of periodic boundary conditions, the wave packet undergoes a preferential clockwise or counterclockwise motion around the ring. This behavior is quantified by a discrete momentum operator which assumes a maximum value at the PT -symmetry- breaking threshold. In Chapter 4, I investigate nonuniform lattices where the parity-symmetric hop- ping between neighboring sites can be tuned. I find that the PT phase remains strong in the case of closest impurities and fragile elsewhere. Chapter 5 explores the effects of the competition between localized and extended PT potentials on a lattice. I show that when the short-range impurities are maximally separated on the lattice, the PT phase is strengthened by adding short-range loss in the broad-loss region. Consequently, I predict that a broken PT symmetry can be restored by increasing the strength of the short-range impurities. Lastly, Chapter 6 summarizes my salient results and discusses areas which can be further developed in future research.
Lashgarian, Azad Nasser. "Dynamic Modelling and Stability Controller Development for Articulated Steer Vehicles." Thesis, 2006. http://hdl.handle.net/10012/2633.
Повний текст джерела