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1
Redmond, D. F. "Delay time analysis in maintenance." Thesis, University of Salford, 1997. http://usir.salford.ac.uk/2157/.
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The thesis develops the application of delay time analysis to the area of mathematical modelling of planned maintenance and inspection of industrial systems. Chapter 1 gives an introduction to the history and techniques in use of maintenance modelling and surveys appropriate literature in the field. A section is devoted to papers published on delay time analysis. Chapter 2 introduces and develops mathematical models for modelling the reliability, maintenance and inspection of repairable systems. Chapter 3 gives an account of parameter estimation and model updating techniques in the light of subjective and observational data sets collected over a period of system operation. Chapter 4 addresses a bias in the probability distribution function of delay time when the data available over an operating survey is censored. Parameter estimation methods for this situation are then proposed. Chapter 5 gives an account of a simulation study of the delay time models and verifies the theory and parameter estimation techniques. Chapter 6 reports on research supported by the Science and Engineering Research Council on the application of delay , time analysis to concrete structures. Finally, Chapter 7 collates the conclusion drawn on each chapter and recommends areas for further research.
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Cheang, Seng. "Synchronisation phenomena with time delay." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/24923.
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I study a simple model of synchronisation proposed by Jensen (2008). The relevant degrees of freedom are expected to be strictly increasing functions of time, such as the total angle swept out by an oscillator. The model is rooted in Winfree's mean-field model for spontaneous synchronisation; some of Winfree's basic assumptions, such as identical or nearly identical dynamics and identical couplings, are therefore retained. I investigated the behaviour of the present model with respect to synchronisation without and in the presence of time delay. The mathematical treatment focuses on characterising the synchronised state as either attractive or repulsive, producing a theory (which ultimately leads to a phase diagram) that compares well with numerics. I employed a perturbative approach, linearising in small time delays and small phase differences. The interaction between individual oscillators is captured by an interaction matrix, which does not require further approximation, i.e. lattice structure enters exactly. To link with established results in the literature, a mean field theory, however, is also studied. The main result is that these typically systems synchronise due to a time delay.
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Hu, Guangdi. "Robustness measures for linear time-invariant time-delay systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ63641.pdf.
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Lombardi, Warody. "Constrained control for time-delay systems." Phd thesis, Supélec, 2011. http://tel.archives-ouvertes.fr/tel-00631507.
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The main interest of the present thesis is the constrained control of time-delay system, more specifically taking into consideration the discretization problem (due to, for example, a communication network) and the presence of constraints in the system's trajectories and control inputs. The effects of data-sampling and modeling problem are studied in detail, where an uncertainty is added into the system due to additional effect of the discretization and delay. The delay variation with respect to the sampling instants is characterized by a polytopic supra-approximation of the discretization/delay induced uncertainty. Some stabilizing techniques, based on Lyapunov's theory, are then derived for the unconstrained case. Lyapunov-Krasovskii candidates were also used to obtain LMI conditions for a state feedback, in the ''original" state-space of the system. For the constrained control purposes, the set invariance theory is used intensively, in order to obtain a region where the system is ''well-behaviored", despite the presence of constraints and (time-varying) delay. Due to the high complexity of the maximal delayed state admissible set obtained in the augmented state-space approach, in the present manuscript we proposed the concept of set invariance in the ''original" state-space of the system, called D-invariance. Finally, in the las part of the thesis, the MPC scheme is presented, in order to take into account the constraints and the optimality of the control solution.
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Dooley, Saul. "Subsample time delay and Doppler estimation." Thesis, University of Strathclyde, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248768.
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Cui, X. "Delay time modelling and software development." Thesis, University of Salford, 2002. http://usir.salford.ac.uk/2159/.
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Delay time modelling (DTM) is the process to establish the mathematical model based on the delay time concept and then to use it for improving plant maintenance management. The delay time model can be divided into a single component model (component-tracking model) or a complex system model (pooled-components model). DTM has been proved to be a methodology readily embraced by engineers for modelling maintenance decisions. The application and research of delay time modelling has come to a stage where a semi-automated tool can be developed. In this thesis, the research on the software development of delay time modelling will be presented. Firstly, delay time models for both a single component (or component-tracking model) and a complex system (or pooled-components model) are introduced. The key part is delay time parameter estimation, which will be presented in details using available subjective, objective or both Secondly, the development of the software package is presented. It includes project analysis, database design, and program design. In the project analysis phase, the delay time models are transformed to program models. All analysis of program models consists of three parts, such as input, processing and output. In the database design phase, some tables are created to store processing information, which is then used in subsequent mathematical modelling. Detailed programming work is given in the program design phase. The major achievement of this research and an open discussion of future work conclude the thesis.
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Schoen, Gerhard Manfred. "Stability and stabilization of time-delay systems." Online version, 1995. http://bibpurl.oclc.org/web/33909.
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Lehman, Bradley M. "Vibrational control of nonlinear time delay systems." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/14718.
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Haurani, Ammar. "Robust control of uncertain time-delay systems." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84257.
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This work addresses the problem of robust stabilization and robust Hinfinity control of uncertain time-delay systems. The time-delays are considered to be present in the states and/or the outputs, and the uncertainties in the system representation are of the parametric norm-bounded type. Both cases of actuators, with and without saturation are studied, and the state-feedback and output-feedback control designs are presented. Two methods for analysis and synthesis of controllers are used: The first is based on the transfer function, and the second on the use of functionals.In the context of the design method based on transfer functions, the problem of Hinfinity output feedback design for a class of uncertain linear continuous-time or discrete-time systems, with delayed states and/or outputs (only for the continuous-time case), and norm-bounded parametric uncertainties is considered. The objective is to design a linear output feedback controller such that, for the unknown state and output time-delays and all admissible norm-bounded parameter uncertainties, the feedback system remains robustly stable and the transfer function from the exogenous disturbances to the state-error outputs meets the prescribed Hinfinity norm upper-bound constraint. The output feedback structure does not depend on the time-delay. The conditions for the existence of the desired robust Hinfinity output feedback and the analytical expression of these controllers, are then characterized in terms of matrix Riccati-type inequalities. In the continuous-time context, both the time-invariant and the time-varying cases are treated. Finally, examples are presented to demonstrate the validity and the solvability of the proposed design methods.
Still in the same context, the state-feedback robust stabilization problem for neutral systems with time-varying delays and saturating actuators is addressed. The systems considered are continuous-time, with parametric uncertainties entering all the matrices in the system representation. The model used for the representation of actuator saturations is that of differential inclusions. A saturating control law is designed and a region of initial conditions is specified within which local asymptotic stability of the closed-loop system is ensured.
Finally, the robust output-feedback stabilization problem for state-delayed systems with time-varying delays and saturating actuators is addressed. The systems considered are again continuous-time, with parametric uncertainties entering all the matrices in the system representation. Two models are used for the representation of actuator saturations: sector modeling and differential inclusions. Saturating control laws are designed, and in the case of differential inclusions, a region of initial conditions is specified within which local asymptotic stability of the closed-loop system is ensured. (Abstract shortened by UMI.)
10
Corvi, Andrea P. "Subjective Time Perception Predicts Delay of Gratification." Case Western Reserve University School of Graduate Studies / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1291765358.
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Pham, Viet Thanh. "Memristor-based and time-delay nonlinear circuits." Doctoral thesis, Università di Catania, 2013. http://hdl.handle.net/10761/1306.
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The pioneering works of Prof. Leon O. Chua constructing electrical circuit (named Chua s circuit) which can display chaotic behaviors open a period with fruitful researches about nonlinear circuits. A considerable amount of different nonlinear circuits has been introduced and their numerous applications have developed instantaneously. Complex dynamical characteristics of nonlinear circuits are used to model complex systems, to generate random numbers or to secure informations. There are three nonlinear systems which have received much attention recently: time delay system, Cellular Neural Network and memristive system. In this thesis we investigate how the properties of these nonlinear systems can be efficiently exploited to build novel chaotic systems and to observe novel complex phenomena.
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Du, Baozhu, and 杜宝珠. "Stability analysis and controller synthesis of continous-time linear time-delay systems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B44765186.
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Olsson, Mattias. "Contributions to Frequency Offset and Time Delay Estimation." Licentiate thesis, Linköping : Linköping University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-6436.
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Boudreau, Daniel. "Joint time delay estimation and adaptive filtering techniques." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=70177.
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This thesis studies adaptive filters for the case in which the main input signal is not synchronized with the reference signal. The asynchrony is modelled by a time-varying delay. This delay has to be estimated and compensated. This is accomplished by designing and investigating joint delay estimation and adaptive filtering algorithms. First, joint maximum likelihood estimator is derived for input Gaussian signals. It is used to define a readily implementable joint estimator, composed of an adaptive delay element and an adaptive filter. Next, two estimation criteria are investigated with that structure. The minimum mean squared error criterion is used with a joint steepest-descent adaptive algorithm and with a joint least-mean-square adaptive algorithm. The general convergence conditions of the joint steepest-descent algorithm are derived. The joint LMS algorithm is analysed in terms of joint convergence in the mean and in the mean square. Finally, a joint recursive least squares adaptive algorithm is investigated in conjunction with the exponentially weighted least squares criterion. Experimental results are obtained for these different adaptive algorithms, in order to verify the analyses. The results show that the joint algorithms improve the performance of the conventional adaptive filtering techniques.
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嚴利興 and Li-hing Yim. "Some stability results for time-delay control problems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31225482.
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Choi, K. M. "Semi-Markov and delay time models of maintenance." Thesis, University of Salford, 1997. http://usir.salford.ac.uk/2158/.
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This thesis is concerned with modelling inspection policies of facilities which Qraduallv deteriorate in time. The context of inspection policies lends itself readily to probabilistic modelling. Indeed, many of the published theoretical models to be found in the literature adopt a Markov approach, where states are usually 'operating', 'operating but fault present', and 'failed'. However, most of these models fail to discuss the 'fit' of the model to data,a nd virtually no exampleso f actual applications or case-studiesa re to be found. hi a series of recent papers dating from 1984, a robust approach to solve these problems has been introduced and developed as the Delay Time Model (DTM). The central concept for this model is the delay time, h, of a fault which is the time lapse from when a fault could first be noticed until the time when its repair can be delayed no longer because of unacceptable consequences. The bottle neck in delay time modelling is how to estimate the delay time distribution parameters. Two methods for estimating these parameters have been developed. namely the subjective method and the objective method. Markov models have the advantage of an extensive body of theory. 'fliere are, however. difficulties of definition, measurement, and calculation when applying Markov models to real-world situations within a maintenance context. Indeed. this problem has motivated the current research which ainis to explore the two modelling methodologies in cases where comparison is valid, and also to gain an insight as to how robust Markov inspection models can be as decision-aids where Markovian properties are not strictly satisfied. It Nvill be seen that a class of inspection problems could be solved by a serni- Markov model using the delay time concept. In this thesis, a typical senii-i%Ia, rkov inspection model based upon the delay time concept is presented for a complex repairable systein that may fail during the course of its service lifetime and the results are compared. Finally, a case study of the senii-Markov inspection model and the delay time model is discussed.
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Tobenkin, Mark M. "Nonlinear filtering for narrow-band time delay estimation." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/53166.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2009.Includes bibliographical references (p. 101-103).
This thesis presents a method for improving passive acoustic tracking. A large family of acoustic tracking systems combine estimates of the time difference of arrival (TDoA) between pairs of spatially separated sensors - this work improves those estimates by independently tracking each TDoA using a Bayesian filter. This tracking is particularly useful for overcoming spatial aliasing, which results from tracking narrowband, high frequency sources. I develop a theoretical model for the evolution of each TDoA from a bound placed on the velocity of the target being tracked. This model enables an efficient form of exact marginalization. I then present simulation and experimental results demonstrating improved performance over a simpler nonlinear preprocessor and Kalman filtering, so long as this bound is chosen appropriately.
by Mark M. Tobenkin.
M.Eng.
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Wetzel, John Adams. "Implementation of time delay control to magnetic bearings." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/42699.
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Yim, Li-hing. "Some stability results for time-delay control problems." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22926094.
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McDaniel, Austin James. "The Effects of Time Delay on Noisy Systems." Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/556867.
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We consider a general stochastic differential delay equation (SDDE) with multiplicative colored noise. We study the limit as the time delays and the correlation times of the noises go to zero at the same rate. First, we derive the limiting equation for the equation obtained by Taylor expanding the SDDE to first order in the time delays. The limiting equation contains a noise-induced drift term that depends on the ratios of the time delays to the correlation times of the noises. We prove that, under appropriate assumptions, the solution of the equation obtained by the Taylor expansion converges to the solution of this limiting equation in probability with respect to the sup norm over compact time intervals. Next, we derive the limiting equation for the SDDE and prove a similar convergence result regarding convergence of the solution of the SDDE to the solution of this limiting equation. We see that the limiting equation corresponding to the equation obtained by the Taylor expansion is an approximation of the limiting equation corresponding to the SDDE. Finally, we study the effects of time delay on a particular model of active Brownian motion.
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Bai, Yuqiong. "ANALYSIS OF AIRCRAFT ARRIVAL DELAY AND AIRPORT ON-TIME PERFORMANCE." Master's thesis, University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2573.
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In this research, statistical models of airport delay and single flight arrival delay were developed. The models use the Airline On-Time Performance Data from the Federal Aviation Administration (FAA) and the Surface Airways Weather Data from the National Climatic Data Center (NCDC). Multivariate regression, ANOVA, neural networks and logistic regression were used to detect the pattern of airport delay, aircraft arrival delay and schedule performance. These models are then integrated in the form of a system for aircraft delay analysis and airport delay assessment. The assessment of an airport¡¯s schedule performance is discussed. The results of the research show that the daily average arrival delay at Orlando International Airport (MCO) is highly related to the departure delay at other airports. The daily average arrival delay can also be used to evaluate the delay performance at MCO. The daily average arrival delay at MCO is found to show seasonal and weekly patterns, which is related to the schedule performance. The precipitation and wind speed are also found contributors to the arrival delay. The capacity of the airport is not found to be significant. This may indicate that the capacity constraint is not an important problem at MCO. This research also investigated the delays at the flight level, including the flights with delay ¡Ý0 minute and the flights with delay ¡Ý15min, which provide the delay pattern of single arrival flights. The characteristics of single flight and their effect on flight delay are considered. The precipitation, flight distance, season, weekday, arrival time and the time spacing between two successive arriving flights are found to contribute to the arrival delay. We measure the time interval of two consecutive flights spacing and analyze its effect on the flight delay and find that for a positively delayed flight, as the time space increases, the probability of the flights being delayed will decrease. While it was possible to calculate the immediate impact of originating delays, it is not possible to calculate their impact on the cumulative delay. If a late departing aircraft has no empty space in its down line schedule, it will continue to be late. If that aircraft enters a connecting airport, it can pass its lateness on to another aircraft. In the research we also consider purifying only the arrival delay at MCO, excluding the flights with originating delay >0. The model makes it possible to identify the pattern of the aircraft arrival delay. The weather conditions are found to be the most significant factors that influence the arrival delay due to the destination airport.M.S.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Civil Engineering
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Zinck, Melissa M. "A COMPARISON STUDY OF CONSTANT TIME DELAY AND PROGRESSIVE TIME DELAY IN THE ACQUISITION OF ACADEMIC CONTENT FOR STUDENTS WITH INTELLECTUAL DISABILITIES." UKnowledge, 2018. https://uknowledge.uky.edu/edsrc_etds/59.
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Constant time delay (CTD) and progressive time delay (PTD) are both evidence-based practices used to teach students with intellectual disability (ID). The prompt delay strategies have been used for instruction with academics, social, vocational, and communication skills. There is limited research regarding the differential effectiveness of the time delay variations for teaching academic content to students with ID. The present study compares the effects of CTD and PTD in the acquisition of academic content with four students with ID. An adapted alternating treatments design was used to compare the effectiveness and efficiency of the two procedures. Generalization was assessed across settings, participants, and materials. Results indicated that both strategies were effective but PTD was more efficient in regards to number of errors and average time to criterion.
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Cruz, David F. "Repair cycle time reduction at Naval Aviation Depots via reduced Logistics Delay Time." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1997. http://handle.dtic.mil/100.2/ADA342536.
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Thesis (M.S. in Management) Naval Postgraduate School, December 1997."December 1997." Thesis advisor(s): Keebom Kang, Donald Eaton. Includes bibliographical references (p. 87). Also available online.
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Pietarila, Kristel M. Fales Roger. "Developing and automating time delay system stability analysis of dynamic systems using the Matrix Lambert W (MLW) function method." Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6180.
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Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 16, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Dr. Roger Fales. Vita. Includes bibliographical references.
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Alwan, Mohamad. "Stability of Hybrid Singularly Perturbed Systems with Time Delay." Thesis, University of Waterloo, 2006. http://hdl.handle.net/10012/2934.
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Hybrid singularly perturbed systems (SPSs) with time delay are considered and exponential stability of these systems is investigated. This work mainly covers switched and impulsive switched delay SPSs . Multiple Lyapunov functions technique as a tool is applied to these systems. Dwell and average dwell time approaches are used to organize the switching between subsystems (modes) so that the hybrid system is stable. Systems with all stable modes are first discussed and, after developing lemmas to ensure existence of growth rates of unstable modes, these systems are then extended to include, in addition, unstable modes. Sufficient conditions showing that impulses contribute to yield stability properties of impulsive switched systems that consist of all unstable subsystems are also established. A number of illustrative examples are presented to help motivate the study of these systems.
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Imaida, Takashi. "STUDIES ON BILATERAL CONTROL OF TELEOPERATOR UNDER TIME DELAY." 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/200503.
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Mitchell, Richard James. "Multi-microprocessor control of processes with pure time delay." Thesis, University of Reading, 1987. http://centaur.reading.ac.uk/18826/.
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Han, Xiaoran. "Output feedback sliding mode control for time delay systems." Thesis, University of Kent, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.594201.
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This Thesis considers Sliding Mode Control (SMC) for linear systems subjected to uncertainties and delays using output feedback. Delay is a natural phenomenon in many practical systems, the effect of delay can be the potential cause -of performance deterioration or even instability. To achieve better control performance, SMC with output feedback is considered for its inherent robustness feature and practicality for implementation. In highlighting the main results, firstly a novel output feedback SMC design is presented which formulates the problem into Linear Matrix Inequalities (LMIs). The efficiency of the design is compared with the the existing literature in pole assignment. eigenstructure assignment and other LMI methods, which either require more constraints on system structures or are computationally less tractable. For systems with timevarying Slate delay, the method is extended to incorporate the delay effect in the controUer synthesis. Both sliding surface and controller design are formulated as LMI problems. For systems with input/output delays and disturbances. the robustness of SMC is degraded with arbitrarily small delay appearing in the high frequency switching component of the controller. To solve the problem singular perturbation method is used to achieve bounded performance which is proportional to the magnitudes of delay, disturbance and switching gain. The applied research has produced two practical implementation studies. Firstly it relates to the pointing control of an autonomous vehicle subjected to external disturbances and friction resulting from the motion of the vehicle crossing rough terrain. The second implementation concerns the attitude control of a flexible spacecraft with respect to roil, pitch and yaw attitude angles.
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Wong, Man-kwun, and 黃文冠. "Some sensitivity results for time-delay optimal control problems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31223655.
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Wang, W. "Modelling condition monitoring inspection using the delay-time concept." Thesis, University of Salford, 1992. http://usir.salford.ac.uk/2156/.
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In the literature on inspection modelling, the failure distribution traditionally plays a fundamental role in model construction in that it is assumed that system failures occur instantly at random time points from new with a known pdf. of time to failure. Numerous models have been built on this basis. However, Professor Christer challenged this traditional idea and proposed the concept of delay time. The idea, which is an essential part of most engineers' experience, assumes that defects do not just appear as failures, but are present for a while before becoming sufficiently obvious to be noticed and declared as failures. The time lapse from when a defect could first be identified at an inspection to consequential failure has been termed the "delay time". It is this idea which can be captured to reveal the nature and scope for preventive maintenance or inspection. It appears that the concept is now being taken up by many other authors. In this thesis, various models for condition monitoring inspection are built on the basis of delay time analysis. Extensions and further developments are made here to enrich the delay-time modelling. Since the distribution of the delay time is important to delay time modelling, a new approach to estimate the delay time distribution is proposed. This technique, which contrasts with the previous subjective data estimation technique, is based upon objective data. Assuming the distribution of the delay time is known, models of condition monitoring inspection are fully discussed for both perfect and imperfect inspections, and for infinite and finite time horizons. Based upon the models for perfect inspection, algorithms are presented to find the optimal solution. Numerical examples are presented in each Chapter to illustrate how models and algorithms work.
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Chan, Lipton. "Time-series prediction using evolutionary lateral-delay neural networks." Thesis, University of Glasgow, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272850.
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Ottensmeyer, Mark Peter. "Telerobotic surgery : feedback time delay effects on task assignment." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10972.
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Nelson, Tom. "ALAMOUTI SPACE-TIME CODING FOR QPSK WITH DELAY DIFFERENTIAL." International Foundation for Telemetering, 2003. http://hdl.handle.net/10150/607483.
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International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, NevadaSpace-time coding (STC) for QPSK where the transmitted signals are received with the same delay is well known. This paper examines the case where the transmitted signals are received with a nonnegligible delay differential when the Alamouti 2x1 STC is used. Such a differential can be caused by a large spacing of the transmit antennas. In this paper, an expression for the received signal with a delay differential is derived and a decoding algorithm for that signal is developed. In addition, the performance of this new algorithm is compared to the standard Alamouti decoding algorithm for various delay differentials.
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Wang, Rong-Jyue, and 王榮爵. "Robust Stability Analysis and Control Design in Non-Time-Delay and Time-Delay Systems." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/7755ut.
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博士國立中央大學
電機工程研究所
83
This dissertation presents a thoroughgoing study on the stability analysis and controller design of systems with time- delays and perturbations. Since time-delays and perturbations are frequently a source of instability and are often encountered in various engineering systems, stability analysis and stabilization for the time-delay uncertain systems are therefore extremely improtant. Based on Lyapunov stability theorem, the solution of Riccati equation, and on Convex combination property, we propose some conditions under which the poles of a closed-loop system with real parameter uncertainties can be assigned within the specified region by using linear state feedback. Two types of specified regions are considered: (i) the region to the left of Re(s) = -σ, and (ii) the disk D(α,r) with center (α,0) and radius r. However, we consider systems with the uncertainties, which may exist on the system matrix and/or the input matrix, are decomposed into the matching and the mismatching portions. Because of the decomposition of the uncertainties, the system may be desgined to tolerate larger uncertainties. These design approaches are also extended to observer-controller design of perturbed large- scale systems. For linear continuous-time systems with time- delays, several new stability criteria are presented by the corresponding simple connected regions. From these regions, the stability of the system can be checked easily by inspecting the locations of the eigenvalues of the system matrix A_0 or its delay matrix A_d. In terms of the fundamental matrix and the Jordan canonical form of the system matrix A_0, several new and simple α-stability criteria for multiple non-commensurate time- delay uncertain systems are also proposed. Moreover, for the perturbed discrete-time system with multiple time-delays, several new conditions are propoaed to ensure that all roots of the characteristic equation lie inside a specified disk D(α,r ) with center (α,0) and radius r.
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Wu, Day-Ru, and 吳岱儒. "Analysis of Time-Delay Systems." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/42854664257244592039.
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碩士國立中央大學
電機工程研究所
88
In this thesis, stability of linear time-invariant time-delay systems is considered. An imaginary axis intersection sequence of delay times is decided. Then some necessary and sufficient conditions for stability are derived. Therefore, the maximum delay time interval is obtained. In addition, the multiple delay time intervals allowed may be determined. And using the scheme proposed in this thesis, some examples reveal that time-delay systems stability is not necessary that the allowable delay time must vary from zero. In the sequel, stability of linear time-invariant systems with multiple time delays is considered. Finally, linear time- delay systems with decay rate that is dependent on the delay is studied. Some examples are provided to illustrate the merits of the proposed method.
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許博森. "Time-Frequency Distribution Method for Time Delay Estimation." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/52171881108671765353.
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碩士國立中山大學
電機工程研究所
81
In this thesis, a new method different from the conventional time domain methods is proposed for time delay estimation. The new method is based on Wigner distribution (WD) with direct delay estimation formula. By the WD, we can obtain the repesentation of signal in both the time and frequency domains. To demonstrate the performance of the presented method, the colored Gaussian signal and the colored Gaussian noise are considered where the additive noises in both sensors are assumed to be uncorrelated with each other. From the simulation results for stationary time delay, we found that the performance of the presented method is better than the conventional time domain methods, viz; the adaptive first-order and second-order cumulants.
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Wu, Tian-Hong, and 吳天弘. "Delay-dependent controller design of uncertain singular time-delay systems." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/84049804126273262044.
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碩士國立高雄應用科技大學
電機工程系博碩士班
96
The problems of delay-dependent robust stabilization and robust H∞ performance of uncertain singular systems with norm-bounded parametric uncertainty are studied in this thesis. Firstly, a delay-dependent stability criterion in terms of linear matrix inequalities (LMIs) for the nominal singular time-delay systems is established, which guarantees the system to be regular, impulse free and asymptotically stable. Secondly, based on this criterion, we design state feedback controllers and observered-based state feedback controllers respectively for uncertain singular time delay systems to guarantee the closed-loop systems are regular, impulse free and robustly stable. Then, we focus on H∞ performance of singular systems and design robust resilient H∞ state feedback controllers and robust resilient H∞ observer-based state feedback controller respectively. Finally, we give some examples to show that we can find controll-er parameters using a simpler method than that in the literature,and the simulated results are better than there.
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Liu, Pin-Lin, and 劉柄麟. "Robust Stability for Parameterically Perturbed Time-delay Systems with Delay-Dependence." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/38151420074751136670.
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博士國立彰化師範大學
工業教育學系
89
In this dissertation, a complete research on the analysis of several types of time-delay dynamic systems is explored. Our results can be classified into five major categories. First, for the delay-dependent stability analysis, sliding model control design, large-scale system and neutral systems, to guarantee the asymptotic stability will be presented. Second, several kinds of controllers for uncertain saturating actuator systems are considered. This includes the stabilization of input constrained systems, stabilization of classes of singularly perturbed and bilinear time-delay systems. Third, we derive the upper bounds for delay time constant such that time delay systems still keep their asymptotic stability, if they are nominally stable and the stability robustness bounds remain smaller than the upper bounds. The criteria of discussed asymptotic stability robustness bounds of linear neutral delay-differential systems are also investigated. Furthermore, by the present schemes, the bounds of tolerable perturbation of above systems are also investigated. Fourth, some sufficient conditions for uniformly asymptotic stability for linear and nonlinerar time-varying discrete multiple time-delay systems with delay-dependent are derived. Finally, as far as we ware, this paper seems to be the first one to discuss the robust stability problems for grey continuous case and discrete case grey time-delay systems via interval systems. The superiority of these obtained results are shown by comparing with previous findings and ample examples are given to confirm the correctness and to demonstrate the applicability. The improvements of our results over those in recent literature are also illustrated if the comparisons are possible.
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Liu, Bing-Lin, and 劉枯麟. "Robust stability for linear uncertain time-delay systems with delay-dependence." Thesis, 1991. http://ndltd.ncl.edu.tw/handle/19648893164899919197.
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林韋男. "Robust Stability for Uncertain Time Delay-Actuator Saturation with Delay-dependence." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/52636752713716686939.
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碩士建國科技大學
電機工程系暨研究所
97
This paper aims to explore robust stability analysis of time delay system. Robust stability for time delay system has been attracting the attention of many researchers. Time delay is frequently encountered in various control systems, and the existence of the delay is a source of instability. Therefore, the stability problem of time delay systems has been one of the most popular research areas in control systems over the years. Time delay system is often occurring in the transmission of information or material between different parts of a system. Transportation systems, communication systems, chemical processing systems, and power systems are examples of time delay systems. In control system design, the limited power supply is the form of a saturating actuator in a practical system. In this thesis, one delay dependent robust stability criteria based on Lyapunov-Krasovskii functional combining with LMI approach has been developed and derived step by step. The proposed stabilization criteria is relatively simple to be checked by simulations and can be applied to the time delay systems with actuator saturation and perturbation. The given systems have been proven to be asymptotically stable.
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Lin, Geng Sian, and 林耕賢. "Time Delay Compensation on Real-time Pseudo-dynamic Testing." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/nzvndy.
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碩士國立臺北科技大學
土木與防災研究所
98
In a real-time pseudo-dynamic test, time-delay occurring in the process of driving the actuator results in the difference between the measured structural recovering force in reality and the ideal one. It causes erroneous results in the test. Therefore, the study aims to develop a time-delay compensation method which can correct the error due to the time-delay. First, a delay differential equation（DDE）is used to represent the equation of motion of a system including time-delay. Based on the characteristic equation associated with the DDE, we can analytically derive the stability boundary equations which show how the dynamic stability of the system is affected by the time delay. We investigate the cases in which the time delay is considered to occur respectively and simultaneously in the recovering force and the damping force. Next, we modify Newmark explicit method such that it can solve for delay differential equations and explore how the time response of a structure is influenced by the time-delay. Finally, we derive a time-delay compensation method applied to a real-time pseudo-dynamic test through comparisons between the Newmark explicit method and the modified one. Then, the proposed compensation method is verified both numerically and experimentally if it can eliminate the error caused by the time-delay in the test.
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Berman, Rachel Elisabeth. "Does time perception underlie delay discounting?" 2013. http://hdl.handle.net/2152/21628.
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Delay discounting, the belief that rewards decline in value over time, is a phenomenon observed in several clinical disorders, including Attention Deficit / Hyperactivity Disorder (ADHD), substance abuse disorders, and other impulse control disorders. Delay discounting behavior is characterized by a tendency to choose smaller, more immediate rewards over larger, more delayed rewards. This tendency has been associated with behavioral impulsivity and inability to delay gratification observed in the aforementioned clinical disorders. It has been suggested that time perception may be a salient feature of delay discounting. If the larger, longer-term reward is perceived as being more temporally remote, its relative value decreases and is associated with greater cost, and one becomes more likely to choose the more immediate reward over the longer-term (though optimal) choice. Time perception has been studied in clinical populations, with increased variability of responses as well as both under-production and overestimation of time intervals observed in those with ADHD and other disorders associated with impulsivity. The present study used informational feedback via a metronome to change belief regarding duration of a second--either increasing or decreasing it by approximately 20%. Participants were 132 college-aged students with and without a diagnosis of ADHD. Measures of impulsivity and ADHD symptomatology were collected as well, and participants completed several cognitive tasks measuring working memory and processing speed to explore the impacts of these measures on delay discounting and time perception. While participants were able to reliably incorporate the altered second belief into short estimations of time (i.e., less than a minute), the manipulation failed to generalize to longer-duration temporal estimations, and it did not affect delay discounting. Neither ADHD symptomatology, impulsivity, nor performance on the cognitive tasks were related to delay discounting behaviors, though a working memory measure was correlated with baseline (pre-manipulation) time and one longer duration estimation. This lends support to a relationship between working memory and temporal perception, though the relationship between temporal perception and delay discounting remains elusive. Directions for future studies to clarify the role of temporal processing and ADHD in delay discounting are discussed.text
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Wei-Chuan, Huang, and 黃偉筌. "Robust Stabilization for Time-delay Systems." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/12082605463955173366.
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碩士建國科技大學
電機工程所
94
Abstract Some discussions have been made with the same examples that appear in many recent papers via illustrative examples. A neutral system with distributed time-delay is asymptotically stable. In this thesis, The control system applied the properties of the Lyapunov equation, Lyapunov -Krasovskiiand, linear matrix inequality(LMI), Newton-Leibniz formula and model transformation. These properties are employed to investigate the robust stabilization conditions. This thesis shows a maximum delay bound is derived for the robust stabilization of time-delay control systems. This thesis shows examples that the Physics mean a control system of time-delay, including Stream Water Quality, Electrical-circuit Models and Heat Exchanger Dynamics. The control system can maximum the allowable delay bound to a greater degree than the memoryless state feedback via illustrative examples. A system with distributed delay is asymptotically stable. Keyword : Lyapunov function, Linear Matrix Inequality(LMI), Time-delay, Neutral system.
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LAI, JING-XUN, and 賴菁勳. "Time delay system adaptive control design." Thesis, 1986. http://ndltd.ncl.edu.tw/handle/61205535919000690295.
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Wang, Jung, and 王融. "Degenerate Semilinear Equation with Time Delay." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/42448687518223937302.
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碩士大同大學
應用數學學系(所)
96
Let $q$ be a nonnegative real number, $\tau $ be a positive number, $\triangle $ be the $n$ dimensional Laplacian operator, $\Omega $ be bounded in $\mathbb{R}^n$ with $\Omega $ is either an $n$-dimensional ball or a square. This paper studies the existence and non-existence of the solution $u(t,x)$ of the parabolic problem: \[ \begin{array}{c} \|x\|^{q}u_{t}(t,x)-K(\Delta u(t,x))=f(u(t-\tau,x)) \mbox{\ for \ } t>0, x\in \Omega, \\ u(t,x)=\eta(t,x) \mbox{\ for\ } -\tau \leq t \leq 0, x\in \Omega, \\ u(t,x)=0 \mbox{ \ on \ } \partial \Omega, \\ \end{array} \] where $\eta (t,x)$ is a nonnegative H\"{o}lder continuous function in $[-\tau,0]\times \Omega$, $K$ is a positive constant representing the diffusion coefficient, and $f(u)$ is a reaction function which is singular at some point $c^{*}>0$. The criteria for the existence and non-existence of the solution is given.
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Chiang, Tai-Li, and 江泰利. "Robust control of time-delay system." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/03805052061886404633.
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碩士國立中央大學
電機工程學系
85
In this paper, we will deal with the time-delay systems with parametric perturbation. In the practical system, because of varying of the enviroment,the parameters of the systems have some uncertainties. And another problem weconcered is time-delay problem. In the practical system, states transmissionneed times, so time-delay problem would happen. Because of the above reasons,we will discuss the robust stability of the time-delay systems in this paper. The topics of this paper have the follows: D-stability of the discrete time-delay systems with parametric perturbation, D-stability of the continuoustime-delay systems with parametric perturbation, the design method of time- delay systems, and the robust stability of the large-scale systems. Finally,we make a conclusion.
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Huang, Gwo-Chin, and 黃國欽. "A Time-delay enhancement to PID Controller." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/50766170862181524307.
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碩士逢甲大學
自動控制工程研究所
84
A tuning method of a time-delay enhanced PID controller (PIDl) for the first-order-plus-dead-time model is presented in the study. Optimum PIDl controller tuning data based on the model and minimum IAE criterion were obtain via Powell searching technique, and these data were then empirically correlated into several regression equations by a least-square method. Thus, PIDl controller tuning based on the model can easilly be obtained by the calculation of these correlated equations. Simulation with a reset-feedback PIDl control algorithm has demonstrated that the proposed tuning method based on the first-order model can provide better results than classical controllers ,especially for the those processes having very largedead time.
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WU, JIE-GIAN, and 吳介騫. "Time delay estimation using orthogonal functions expansion." Thesis, 1986. http://ndltd.ncl.edu.tw/handle/81810630189402776480.
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"Singular external control problem with time delay." Chinese University of Hong Kong, 1986. http://library.cuhk.edu.hk/record=b5885694.
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ZHU, YAO-DONG, and 朱耀東. "Analysis and control of time-delay system." Thesis, 1986. http://ndltd.ncl.edu.tw/handle/w7vmd2.
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