Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 31 for “"Stochastic system"”.
-
Nonlinear stochastic system identification techniques for biological tissues/
… The enabling technology is the use of nonlinear stochastic system identification techniques in conjunction with a high bandwidth actuator to perturb the tissue. The desktop and handheld instruments used for this investigation were custom-built Lorentz force actuators which were able to measure …
-
Managing Complex Water Resource Systems for Ecological Integrity: Evaluating Tradeoffs and Uncertainty
Water resource systems often contain numerous components that are intertwined or contradictory, such as power production, water delivery, recreation, and environmental needs. This complexity makes it difficult to holistically assess management alternatives. In addition, hydroclimatic and ecological …
-
Stochastic stability and global bifurcations in gyroscopic mechanical systems
… stability and bifurcation behavior of mechanical systems parametrically excited by small periodic or stochastic perturbations is studied. In the case of random excitation, the almost-sure and moment asymptotic stability of two- and four-dimensional dynamical systems subject to small intensity …
-
Deterministic Fluid Models for Internet Congestion Control
… model as the deterministic limit of a stochastic system with a large number of users. We argue that, a virtual-queue-based AQM scheme is very robust to the choice of parameters in achieving a low-loss, low-delay, and high-utilization operation. However, with a real-queue-based marking, …
-
Design of a Testing Fixture for the Characterization and Modeling of a Powered Prosthetic Ankle Using a Lorentz Force Actuator
… approach through the use of nonlinear stochastic system identification techniques to characterize the prosthetic. Results from initial experiments which use the method for characterizing known linear models revealed unaccounted for sources of error and nonlinearity which future work …
-
Modified Stochastic Sine-Gordon Equation
The main focus of my dissertation is the Modified Stochastic Sine-Gordon Equation: utt = 2uxx − ut − sin(|u|^(&gamma)) + b(u, du/dt)dW/dt where &gamma > 0 is the parameter of the power of non-linearity, &delta &ge 0 is the magnitude of non-linearity, &alpha> 0 be the damping parameter, and &sigma …
-
Hamilton-Jacobi-Bellman equation for stochastic optimal control: Applications to spacecraft attitude control
… presence of thrust uncertainty, which leads to stochastic accelerations. Spacecraft equipped with electric propulsion and other low thrust mechanisms, often experience random fluctuations in thrust. These stochastic processes arise from sources such as uncertain power supply output, varying …
-
Cooperative Payload Transportation by UAVs: A Model-Based Deep Reinforcement Learning (MBDRL) Application
… Sampling (PETS) algorithm to model the unknown stochastic system dynamics and uncertainty. We use the Multi-Agent Reinforcement Learning (MARL) framework via a centralized controller in a leader-follower configuration. The agents utilize the approximated transition function in a Model Predictive …
-
Stochastic and deterministic multipatch epidemic models
… thresholds for both the deterministic and the stochastic system through an approximating multi-type branching process. We formulate a continuous time Markov Chain that corresponds to each deterministic system studied. The main idea will be to study the spectral radius of the next generation …
-
Development of a miniature, continuous measurement, stochastic perturbation gas chromatograph
… part of this thesis explores the application of stochastic system identification techniques applied to chromatography to enable continuous chromatographic measurements, multiplexing of instrument components, and the ability to optimally tune instrumentation parameters and reduce chromatogram …
-
Some mathematical problems in the dynamics of stochastic second-grade fluids
… present work we initiate the investigation of a stochastic system of evolution partial differential equations modelling the turbulent flows of a bidimensional second grade fluid. Global existence and uniqueness of strong probabilistic solution (but weak in the sense of partial differential …
-
Optimal financial policies in an open economy: the UK case
… type, although we also approximate a closed-loop stochastic system by perturbing the system with certain shocks and optimizing again. Among the pegging regimens considered, the one involving targets for foreign reserves and the monetary aggregate seems to be preferable. However, the analysis also …
-
Kernel-based approximate dynamic programming using Bellman residual elimination
… problems related to multi-agent robotic systems can be naturally posed as Markov Decision Processes (MDPs). An important advantage of the MDP framework is the ability to utilize stochastic system models, thereby allowing the system to make sound decisions even if there is randomness in …
-
Automated verification of model-based programs under uncertainty
Highly robust embedded systems have been enabled through software executives that have the ability to reason about their environment. Those that employ the model-based autonomy paradigm automatically diagnose and plan future actions, based on models of themselves and their environment. This …
-
System identification of the vestibular ocular reflex via visual and vestibular co-stimulation
… understanding the performance of the vestibular system and for the diagnosis of dysfunction. Limitations in experimental equipment and in the analytic methods applied have resulted in VOR testing being conducted under artificial laboratory conditions that do not resemble the conditions under …
-
Controller design for underwater vehicle systems with communication constraints
… model technique. The resulting coupled linear stochastic system is suitable for networked control. The second area of work presents a unified formalism for multi-vehicle control and estimation with measurement, control, and acknowledgment packets all subject to scheduling, delays and packet …
-
Stochastically Constrained Simulation Optimization On Mixed-Integer Spaces
… the problem of identifying solutions to a stochastic system under multiple constraints. The objective function and the constraints are expressed in terms of performance measures of the system that are observable only via a simulation model parameterized by a finite number of decision …
-
Robust parameter optimization strategies in computer simulation experiments
… the simulation model represents the real world system under study. This dissertation addresses a major cause of model validity problems: the dissimilarity between the simulation model and the real system due to the dynamic nature of the real system that results from the presence of nonstationary …
-
Optimal control of dynamical systems with time-invariant probabilistic parametric uncertainties
… algorithms for the optimal control of dynamical systems with time-invariant probabilistic uncertainties. The main contribution of this thesis is new feedback control design algorithms for linear time-invariant systems with time-invariant probabilistic parametric uncertainties and stochastic …
-
Airline scheduling and air traffic control : incorporating uncertainty and passenger and airline preferences
… global airline industry is a multi-stakeholder stochastic system whose performance is the outcome of complex interactions between its multiple decisions-makers under a high degree of uncertainty. Inadequate understanding of uncertainty and stakeholder preferences leads to adverse effects …
Page 1 of 2