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Showing 1 to 20 of 21 for “"Implicit methods"”.
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Lightly-Implicit Methods for the Time Integration of Large Applications
… time scales, or with complex physical dynamics, implicit time integration schemes are preferred due to their superior stability properties. However, for very large systems accurate solution of the implicit terms can be impractical. For this reason approximations are widely used in the …
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Stability and efficiency properties of implicit Runge-Kutta methods
… section examines certain stability properties of implicit Runge-Kutta methods. In particular, a new stability property is defined, which is a modification to non-autonomous problems of A-stability, and its relation to B-stability is considered. A Runge-Kutta method is written as [see 01front.pdf …
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Time Integration Methods for Large-scale Scientific Simulations
… require the use of numerical time integration methods to solve. Many problems of scientific interest exhibit stiff behavior for which implicit methods are favorable, however standard implicit methods are computationally expensive. They require the solution of one or more large nonlinear systems …
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Stability Analysis of Krylov Subspace Spectral Methods for the 1-D Wave Equation in Inhomogeneous Media
<p>Krylov subspace spectral (KSS) methods are high-order accurate, explicit time-stepping methods for partial differential equations (PDEs) that also possess the stability characteristic of implicit methods. Unlike other time-stepping approaches, KSS methods compute each Fourier coefficient of the …
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The Application of Improved Numerical Techniques to 1-D Micellar/Polymer Flooding Simulation
… in-tegrators were used. Two of them are explicit methods while the other two are implicit methods. Although the implicit methods did not work as well as the explicit methods, there may be some improve-ment possible. With respect to the computation time, one of the explicit methods which is based …
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Analysis and Implementation of High-Order Compact Finite Difference Schemes
… is given. Compact schemes are high order implicit methods for numerical solutions of initial and/or boundary value problems modeled by differential equations. These schemes generally require smaller stencils than the traditional explicit finite difference counterparts. To avoid numerical …
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Mathematical modelling of complex dynamics
… achieving a proper structure factor in modelling methods of block copolymers. The novel models have been developed by implementing CDS via more stable implicit methods, including backward Euler, Crank–Nicolson (CN) and Alternating Direction Implicit (ADI) methods. The CN scheme were implemented …
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A contact-implicit direct trajectory optimization scheme for the study of legged maneuverability
… typically used. Another is the use of “contact-implicit” methods, which allow an appropriate footfall sequence to be discovered, rather than requiring that it be defined upfront. Although contact-implicit methods are not novel, they are not widely-used, as they are computationally demanding, and …
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Αριθμητική επίλυση συνήθων διαφορικών εξισώσεων με περιοδική λύση
… which presents a periodical behaviour. Numerical methods for the numerical solution of the above general problem are being expounded. At first, a sixth order exponentially fitting method, which requires the a priori knowledge of the frequency of the problem, is being expounded. In the same …
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Rapid Approximation of Bilinear Forms Involving Matrix Functions Through Asymptotic Analysis of Gaussian Node Placement
… rates, which present problems for time-stepping methods. Krylov Subspace Spectral methods, developed by Dr. James Lambers, bridge the gap between explicit and implicit methods for stiff problems by computing each Fouier coefficient from an individualized approximation of the solution operator. …
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Numerical solution for subsurface reservoir simulation
… there is an extensive literature on numerical methods for PDEs. In this work, we review some numerical techniques, more precisely we present finite volume method with two-point flux approximation and mixed finite volume method for spatial discretization of elliptic and parabolic PDEs modeling …
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Positivity preserving solutions of partial integro-differential equations
… in chemical engineering. While solution methods for many of these types of problems are well-established, there is growing class of problems that lack standard solution methods: partial integro-differential equations. The primary challenges in solving these problems are due to several …
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Choreographing relations: practical philosophy and contemporary choreography
… qualitatively by elaborating singular methods which couple the issue of movement with the creation of aesthetic regimes. As opposed to a representational outline of choreography’s ontology, my thesis investigates the participatory potential of choreography by focussing on the singular …
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Improving Investigative Interviews: Facilitating Disclosure of Information through Implicit Means
… however, there has been no focus on implicit methods despite their prominence in the basic social cognitive literature. Research on implicit cognition has found that activating mental concepts can lead people to behave in ways that are semantically related to or metaphorically …
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A model for the time dependent behaviour of rock joints
… scheme and therefore a generalised explicit/implicit scheme is chosen. The resulting numerical algorithms are all implemented in the finite element program, NOSTRUM. Various examples are presented to illustrate certain features of both the formulation and the numerical algorithm. Jointed rock …
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Exponential Integrators for the Incompressible Navier-Stokes Equations
… time integration (KBEI). These time integration methods provide a high order accurate, stable approach with many of the advantages of explicit methods, and can reduce the computational resources over conventional methods. The method is scalable in the sense that the computational costs grow …
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Teachers of students who are deaf and hard-of-hearing: Change in reading instruction through collaborative professional development
… qualitative and quantitative data collection methods. Analysis of the data showed that two of the teachers grew substantially in their knowledge of the structure of language. While the third teacher did not improve on the knowledge assessment, growth in knowledge was apparent from her …
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Kalman Filtering and its Application to On-Line State Estimation of a Once-Through Boiler
… of the unscented transforms with linearly implicit methods and incorporation of simulation errors in the state estimation problem. The newly developed techniques are then applied to the technically relevant problem of state estimation on the main components of a utility boiler. State …
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Ghost-point methods for Elliptic and Hyperbolic Equations
… applicato per lo sviluppo di un metodo semi-implicito per equazioni di Eulero su domini che presentano ostacoli, per imporre le condizioni al contorno in modo simile a quanto fatto nelle equazioni ellittiche. Questo metodo essendo semi-implicito supera il problema della restrizione spaziale …
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Development of implicit kinetic simulation methods, and their application to ion beam propagation in current and future neutralized drift compression experiments
… of plasma are solved numerically using two implicit Particle-in-Cell methods. The implicit nature of the time-differenced gov- erning equations leads to unconditional numerical stability. The primary numerical scheme is based on an implicit moment Particle-in-Cell approach. It has been …
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