Matches in SemOpenAlex for { <https://semopenalex.org/work/W2337640060> ?p ?o ?g. }
Showing items 1 to 63 of
63
with 100 items per page.
- W2337640060 abstract "Inaccuracies in standard finite difference modeling methods make new laboratory procedures for estimating saturated and unsaturated soil parameters, by calibrating a model to a transient inflow experiment, improbable, if not impossible. Time discretization errors in the first-order-accurate Euler implicit (backward-in-time) time step make the minima for objective functions (used in estimation with Powell's conjugate direction nonlinear optimization method) shift radically with very small changes in time step size. Diagonally-implicit Runge-Kutta (DIRK) time stepping methods are developed. In DIRK time steps, a number of Euler implicit partial time steps are taken and combined linearly with the final implicit time step, using Runge-Kutta methods. For each additional implicit partial time step taken, another power of $Delta$t in the local time discretization error is eliminated, improving the computational accuracy and efficiency of the model substantially. DIRK time steps are also fully compatible with mass-conservative forms of Newton's iteration, and can improve the error-times-effort model quality of a mass-conservative method by factors of from two to over two hundred times, depending on time step size.Another line of inquiry develops the concept of Darcian interblock conductivity means, which requires strict mathematical consistency with Darcy's Law, unlike most standard means. Graphic visualization of Darcian means, derived by numerically solving an elliptic boundary condition problem, demonstrates a rich complexity not previously considered. Darcian means for vertical flow depend not only on soil unsaturated parameters, but on the model space step size. Visualization leads to a new first-order approximation for the gravity flow mean in vertical infiltration, a weighted mean where the weight varies monotonically and nonlinearly with space step size. In an example of zero-head infiltration into dry coarse sand, the new approximation reduces gross mass inflow error and sum-absolute mass distribution error up to three times over previously-accepted means. This demonstrates that interblock means closer to strict mathematical consistency with Darcy's Law produce better results, and calls into question current methods that rely on simple and conveniently-calculated means." @default.
- W2337640060 created "2016-06-24" @default.
- W2337640060 creator A5057094411 @default.
- W2337640060 date "1994-01-01" @default.
- W2337640060 modified "2023-09-24" @default.
- W2337640060 title "Improved algorithms for finite difference modeling of richards' equation" @default.
- W2337640060 hasPublicationYear "1994" @default.
- W2337640060 type Work @default.
- W2337640060 sameAs 2337640060 @default.
- W2337640060 citedByCount "1" @default.
- W2337640060 crossrefType "journal-article" @default.
- W2337640060 hasAuthorship W2337640060A5057094411 @default.
- W2337640060 hasConcept C11413529 @default.
- W2337640060 hasConcept C121332964 @default.
- W2337640060 hasConcept C134306372 @default.
- W2337640060 hasConcept C158622935 @default.
- W2337640060 hasConcept C181582579 @default.
- W2337640060 hasConcept C28826006 @default.
- W2337640060 hasConcept C33923547 @default.
- W2337640060 hasConcept C38409319 @default.
- W2337640060 hasConcept C48753275 @default.
- W2337640060 hasConcept C62520636 @default.
- W2337640060 hasConcept C73000952 @default.
- W2337640060 hasConcept C768646 @default.
- W2337640060 hasConceptScore W2337640060C11413529 @default.
- W2337640060 hasConceptScore W2337640060C121332964 @default.
- W2337640060 hasConceptScore W2337640060C134306372 @default.
- W2337640060 hasConceptScore W2337640060C158622935 @default.
- W2337640060 hasConceptScore W2337640060C181582579 @default.
- W2337640060 hasConceptScore W2337640060C28826006 @default.
- W2337640060 hasConceptScore W2337640060C33923547 @default.
- W2337640060 hasConceptScore W2337640060C38409319 @default.
- W2337640060 hasConceptScore W2337640060C48753275 @default.
- W2337640060 hasConceptScore W2337640060C62520636 @default.
- W2337640060 hasConceptScore W2337640060C73000952 @default.
- W2337640060 hasConceptScore W2337640060C768646 @default.
- W2337640060 hasLocation W23376400601 @default.
- W2337640060 hasOpenAccess W2337640060 @default.
- W2337640060 hasPrimaryLocation W23376400601 @default.
- W2337640060 hasRelatedWork W1619188406 @default.
- W2337640060 hasRelatedWork W1665964624 @default.
- W2337640060 hasRelatedWork W1966545299 @default.
- W2337640060 hasRelatedWork W2006427131 @default.
- W2337640060 hasRelatedWork W2018251972 @default.
- W2337640060 hasRelatedWork W2028725765 @default.
- W2337640060 hasRelatedWork W2043512487 @default.
- W2337640060 hasRelatedWork W2079151551 @default.
- W2337640060 hasRelatedWork W2128462575 @default.
- W2337640060 hasRelatedWork W2139704539 @default.
- W2337640060 hasRelatedWork W2152093955 @default.
- W2337640060 hasRelatedWork W2336901638 @default.
- W2337640060 hasRelatedWork W2389898028 @default.
- W2337640060 hasRelatedWork W243194004 @default.
- W2337640060 hasRelatedWork W2593049247 @default.
- W2337640060 hasRelatedWork W2607025665 @default.
- W2337640060 hasRelatedWork W2756108782 @default.
- W2337640060 hasRelatedWork W2901830423 @default.
- W2337640060 hasRelatedWork W2906268097 @default.
- W2337640060 hasRelatedWork W2775299612 @default.
- W2337640060 isParatext "false" @default.
- W2337640060 isRetracted "false" @default.
- W2337640060 magId "2337640060" @default.
- W2337640060 workType "article" @default.