Scientific programming
Scientific programming of transformations of direction fields and autonomous systems of ordinary differential equations - Optimization of electron-optical potential for star tracker
SEARCH · Engineering Papers
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Scientific programming of transformations of direction fields and autonomous systems of ordinary differential equations - Optimization of electron-optical potential for star tracker
Emerging tensor network techniques for solutions of partial differential equations (PDEs), known for their ability to break the curse of dimensionality, deliver new mathematical methods for ultra-fast numerical solutions of high-dimensional problems. Here, we introduce a Tensor Train (TT) Chebyshev spectral collocation method, in both space and time, for the solution of the time-dependent convection-diffusion-reaction (CDR) equation with inhomogeneous boundary conditions, in Cartesian geometry. Previous methods for numerical solution of time-dependent PDEs often used finite difference for time, and a spectral scheme for the spatial dimensions, which led to a slow linear convergence. Spectral collocation space-time methods show exponential convergence; however, for realistic problems they need to solve large four-dimensional systems. We overcome this difficulty by using a TT approach, as its complexity only grows linearly with the number of dimensions. We show that our TT space-time Chebyshev spectral collocation method converges exponentially, when the solution of the CDR is smooth, and demonstrate that it leads to a very high compression of linear operators from terabytes to kilobytes in TT-format, and a speedup of tens of thousands of times when compared to a full-grid space-time spectral method. These advantages allow us to obtain the solutions at much higher resolutions.
Algebraic matrix Riccati differential equation solution by Newton-Raphson iteration method
Vector-matrix differential equation for second order sensitivity coefficients applied to trajectory optimization, modeling and compensation and guidance and control
Differential equation for passage of plane electromagnetic waves through plane-parallel inhomogeneous plasma slab
Second order forced nonlinear oscillation differential equation with time-dependent term not even, having infinity of periodic solutions
First-order differential equations for quasi- optimum feedback control technique
Differential equation for parent and daughter decay influence on radioactive tracer diffusion profiles
Differential equations of motion linearized about nominal calculus of variation solution to determine coefficients of guidance function
Stability problems in randomly excited dynamic systems, discussing partial differential equations governing evolution of conditional probabilities and expectations
Differential equation technique of representing dynamic systems for optimal control problems, and fundamental role of optimum linear filter
Reformation processes effect on stress-time-to- fracture behavior of solids, considering governing differential equation
Ordinary differential equations for stress analysis of thin spherical shells for initial pressurization
Partial differential equations used to correct values of orbital elements for satellites in near earth orbits
Differential equations of motion for determining dynamic characteristics of variable mass slender elastic body moving under high accelerations
Discrete ordinate method for boundary value problems in gas dynamics using differential equations yields solutions to Couette flow
Nonlinear time-variant phase-lock loop differential equation for arbitrary loop voltage- controlled oscillator sweep voltages used in aerospace tracking and communication systems
Differential equation system for elastic equilibrium of hinge-clamped shallow spherical shell bounded by ellipse and rectangle