One-dimensional continuously distributed sensors for thermophysical fields: method of measurement, model, and numerical algorithm

Measurement ◽  
2021 ◽  
pp. 110082
Author(s):  
Yu.K. Evdokimov ◽  
E.S. Denisov ◽  
L.Yu. Fadeeva
Keyword(s):  
Numerical Algorithm ◽  
Measurement Model ◽  
Distributed Sensors ◽  
One Dimensional ◽  
Method Of Measurement

The Four-States Model of Memory Retrieval Experiences

2007 ◽  
Vol 215 (1) ◽  
pp. 61-71 ◽  
Author(s):  
Edgar Erdfelder ◽  
Lutz Cüpper ◽  
Tina-Sarah Auer ◽  
Monika Undorf
Keyword(s):  
Signal Detection ◽  
Memory Retrieval ◽  
Measurement Model ◽  
Standard Errors ◽  
Parameter Estimates ◽  
Unequal Variances ◽  
One Dimensional ◽  
Detection Model ◽  
Memory States ◽  
The One

Abstract. A memory measurement model is presented that accounts for judgments of remembering, knowing, and guessing in old-new recognition tasks by assuming four disjoint latent memory states: recollection, familiarity, uncertainty, and rejection. This four-states model can be applied to both Tulving's (1985) remember-know procedure (RK version) and Gardiner and coworker's ( Gardiner, Java, & Richardson-Klavehn, 1996 ; Gardiner, Richardson-Klavehn, & Ramponi, 1997 ) remember-know-guess procedure (RKG version). It is shown that the RK version of the model fits remember-know data approximately as well as the one-dimensional signal detection model does. In contrast, the RKG version of the four-states model outperforms the corresponding detection model even if unequal variances for old and new items are allowed for.We show empirically that the two versions of the four-statesmodelmeasure the same state probabilities. However, the RKG version, requiring remember-know-guess judgments, provides parameter estimates with smaller standard errors and is therefore recommended for routine use.

Fully Legendre Spectral Galerkin Algorithm for Solving Linear One-Dimensional Telegraph Type Equation

2019 ◽  
Vol 16 (08) ◽  
pp. 1850118 ◽  
Author(s):  
E. H. Doha ◽  
W. M. Abd-Elhameed ◽  
Y. H. Youssri
Keyword(s):  
Error Analysis ◽  
Boundary Conditions ◽  
Numerical Algorithm ◽  
Type Equation ◽  
High Accuracy ◽  
Basis Functions ◽  
Structured Matrices ◽  
One Dimensional ◽  
Wide Applicability ◽  
Careful Investigation

In this paper, we analyze and implement a new efficient spectral Galerkin algorithm for handling linear one-dimensional telegraph type equation. The principle idea behind this algorithm is to choose appropriate basis functions satisfying the underlying boundary conditions. This choice leads to systems with specially structured matrices which can be efficiently inverted. The proposed numerical algorithm is supported by a careful investigation for the convergence and error analysis of the suggested approximate double expansion. Some illustrative examples are given to demonstrate the wide applicability and high accuracy of the proposed algorithm.

ANALYSIS OF ELASTO-PLASTIC STRESS WAVES BY A TIME-DISCONTINUOUS VARIATIONAL INTEGRATOR OF HAMILTONIAN

2008 ◽  
Vol 22 (31n32) ◽  
pp. 6259-6264
Author(s):  
SANG-SOON CHO ◽  
HOON HUH ◽  
KWANG-CHUN PARK
Keyword(s):  
Finite Element Analysis ◽  
Plastic Deformation ◽  
Numerical Algorithm ◽  
Stress Waves ◽  
Element Analysis ◽  
One Dimensional ◽  
Variational Integrator ◽  
The Stability ◽  
Elastic Unloading ◽  
Plastic Stress

This paper proposes a numerical algorithm of a time-discontinuous variational integrator based on the Hamiltonian in order to obtain more accurate results in the analysis of elasto-plastic stress wave. The algorithm proposed adopts both a time-discontinuous variational integrator and space-continuous Hamiltonian so as to capture discontinuities of stress waves. The algorithm also adopts the limited kinetic energy to enhance the stability of the numerical algorithm so as to solve the discontinuities such as elastic unloading and internal reflection in plastic deformation. Finite element analysis of one dimensional elasto-plastic stress waves is carried out in order to demonstrate the accuracy of the algorithm proposed.

scholarly journals One-dimensional models of radiation transfer in heterogeneous canopies: A review, re-evaluation, and improved model

2020 ◽  
Author(s):  
Brian N. Bailey ◽  
Maria A. Ponce de León ◽  
E. Scott Krayenhoff
Keyword(s):  
Field Data ◽  
Large Scale ◽  
Measurement Model ◽  
Canopy Architecture ◽  
Radiation Interception ◽  
One Dimensional ◽  
Global Circulation Models ◽  
Wide Range ◽  
Vegetation Heterogeneity ◽  
Heterogeneous Canopies

Abstract. Despite recent advances in the development of detailed plant radiative transfer models, the large-scale canopy models generally still rely on simplified one-dimensional (1D) radiation models based on assumptions of horizontal homogeneity, including dynamic ecosystem models, crop models, and global circulation models. In an attempt to incorporate the effects of vegetation heterogeneity or clumping within these simple models, an empirical clumping factor, commonly denoted by the symbol Ω, is often used to effectively reduce the overall leaf area density/index value that is fed into the model. While the simplicity of this approach makes it attractive, Ω cannot in general be readily estimated for a particular canopy architecture, and instead requires radiation interception data in order to invert for Ω. Numerous simplified geometric models have been previously proposed, but their inherent assumptions are difficult to evaluate due to the challenge of validating heterogeneous canopy models based on field data because of the high uncertainty in radiative flux measurements and geometric inputs. This work provides a critical review of the origin and theory of models for radiation interception in heterogeneous canopies, and an objective comparison of their performance. Rather than evaluating their performance using field data, where uncertainty in the measurement model inputs and outputs can be comparable to the uncertainty in the model itself, the models were evaluated by comparing against simulated data generated by a three-dimensional leaf-resolving model in which the exact inputs are known. A new model is proposed that generalizes existing theory, is shown to perform very well across a wide range of canopy types and ground cover fractions.

The Dispersion in Finite Element Solutions to the One-Dimensional Heat Equation

1999 ◽  
Author(s):  
Ashley F. Emery ◽  
Walter Dauksher
Keyword(s):  
Finite Element ◽  
Heat Equation ◽  
Numerical Algorithm ◽  
Mesh Refinement ◽  
Matrix Formulation ◽  
Time Step ◽  
One Dimensional ◽  
The One ◽  
Capacitance Matrix

Abstract A method for evaluating the numerically introduced dispersion in finite element solutions to the one-dimensional heat equation is presented. The dispersion is quantified for linear and quadratic elements as a function of time step, mesh refinement and capacitance matrix formulation. It is demonstrated that an analysis of the dispersion is a useful tool in estimating the accuracy and in understanding the behavior of the numerical algorithm.

scholarly journals Space-time spectral collocation algorithm for solving time-fractional Tricomi-type equations

Open Physics ◽  
2016 ◽  
Vol 14 (1) ◽  
pp. 269-280 ◽  
Author(s):  
M.A. Abdelkawy ◽  
Engy A. Ahmed ◽  
Rubayyi T. Alqahtani
Keyword(s):  
Numerical Algorithm ◽  
Jacobi Polynomials ◽  
High Accuracy ◽  
Basis Functions ◽  
Two Dimensional ◽  
Algebraic Equations ◽  
One Dimensional ◽  
Numerical Tests ◽  
Shifted Jacobi Polynomials ◽  
Derivatives Of

AbstractWe introduce a new numerical algorithm for solving one-dimensional time-fractional Tricomi-type equations (T-FTTEs). We used the shifted Jacobi polynomials as basis functions and the derivatives of fractional is evaluated by the Caputo definition. The shifted Jacobi Gauss-Lobatt algorithm is used for the spatial discretization, while the shifted Jacobi Gauss-Radau algorithmis applied for temporal approximation. Substituting these approximations in the problem leads to a system of algebraic equations that greatly simplifies the problem. The proposed algorithm is successfully extended to solve the two-dimensional T-FTTEs. Extensive numerical tests illustrate the capability and high accuracy of the proposed methodologies.

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