ABSTRACTABSTRACTAiming at tackling the difficulty in establishing a sea surface temperature (SST) dynamical model, this study develops a non-linear dynamical–statistical model of SST fields and their correlative fact...
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ABSTRACTABSTRACTAiming at tackling the difficulty in establishing a sea surface temperature (SST) dynamical model, this study develops a non-linear dynamical–statistical model of SST fields and their correlative factors based on Genetic Algorithms (GA) and the dynamical system reconstruction idea, which greatly improves the El Niño–Southern Oscillation (ENSO) forecast model. Using Hadley SST data, sea surface wind (SSW) and sea level pressure (SLP) data from the National centers for Environmental Prediction-National center for Environmental Research (NCEP-NCAR), with empirical orthogonal function (EOF) time-space for reconstruction, we carry out numerical integral forecasting experiments for SST, SSW, and SLP fields. By statistical analysis of the forecasting experiments, we find that forecasts for less than 25 months perform better than longer term forecasts. Based on the model, we forecast SST, SSW, and SLP fields in September, October, and November 2014 and predict a weak La Niña event. This study explores a novel method for the complex atmosphere–ocean system.Résumé[Traduit par la rédaction] Dans le but de s'attaquer à la difficulté d’établir un modèle dynamique de la température de la surface de la mer (TSM), la présente étude met au point un modèle dynamique–statistique non linéaire des champs de TSM et de leurs facteurs corrélatifs basé sur des algorithmes génétiques et sur le principe de la reconstruction de système dynamique, qui améliore grandement le modèle de prévision de l'El Niño–Oscillation australe (ENSO). À partir des données de TSM du Centre Hadley ainsi que des données de vent à la surface de la mer (VSM) et de pression au niveau de la mer (PNM) du NCEP-NCAR (National centers for Environmental Prediction-National center for Environmental Research), avec un espace-temps de fonction orthogonale empirique pour la reconstruction, nous exécutons des expériences de prévision numériques intégrales pour les champs de TSM, de VSM et de PNM. Par l'analyse s
By using the origin intensity factors to eliminate the singularity of the fundamental solution at source,the singular boundary method(SBM) remedies the perplexing drawback of fictitious boundary in the method of funda...
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By using the origin intensity factors to eliminate the singularity of the fundamental solution at source,the singular boundary method(SBM) remedies the perplexing drawback of fictitious boundary in the method of fundamental solutions(MFS).The origin intensity factors can be analytically evaluated via mathematical manipulations.
This paper presents three boundary meshless methods for solving problems of steady-state and transient heat conduction in nonlinear functionally graded materials(FGMs).The three methods are,respectively,the method of ...
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This paper presents three boundary meshless methods for solving problems of steady-state and transient heat conduction in nonlinear functionally graded materials(FGMs).The three methods are,respectively,the method of fundamental solution(MFS),the boundary knot method(BKM),and the collocation Trefftz method(CTM)in conjunction with Kirchhoff transformation and various variable *** the analysis,Laplace transform technique is employed to handle the time variable in transient heat conduction problem and the Stehfest numerical Laplace inversion is applied to retrieve the corresponding time-dependent *** proposed MFS,BKM and CTM are mathematically simple,easyto-programming,meshless,highly accurate and *** numerical examples of steady state and transient heat conduction in nonlinear FGMs are considered,and the results are compared with those from meshless local boundary integral equation method(LBIEM)and analytical solutions to demonstrate the effi-ciency of the present schemes.
The infinite domain potential problems arise in many branches of scientific and engineering fields, which by now still pose a great challenge to scientific computing *** study proposes a novel meshless singular bounda...
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The infinite domain potential problems arise in many branches of scientific and engineering fields, which by now still pose a great challenge to scientific computing *** study proposes a novel meshless singular boundary method (SBM) to solve infinite domain potential *** SBM is mathematically simple, easy-to-program, meshless and *** guar-antee the uniqueness of numerical solutions, this article adds a constant term into the SBM approximate *** effi-ciency and accuracy of the proposed technique are tested to the three infinite domain potential problems.
The land-atmosphere interaction in the Tibetan Plateau plays an important role in the Asian summer monsoon and the global energy and water cycle. This study presents a method to improve the land surface water and ener...
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The land-atmosphere interaction in the Tibetan Plateau plays an important role in the Asian summer monsoon and the global energy and water cycle. This study presents a method to improve the land surface water and energy fluxes simulation by using a land data assimilation system (LDAS), which merging microwave remote sensing data and GCM output into a land surface model. NCEP reanalysis data is used as the background field and also as the meteorological forcing for the land surface model. Two experiments were designed as by driving LDAS-UT with two sets of atmospheric forcing data, (1) with in situ observed forcing data and (2) with NCEP reanalysis data at Gaize and Naqu sites. Results show that LDAS is able to estimate land surface soil moisture and energy fluxes accurately. The RMSE of soil moisture simulation is around 0.03-0.05 and RMSE of net radiation simulation is around 30W/M". This study reveals the potential for using satellite remote sensing data to improve land surface fluxes estimation.
This paper presents high-order Trefftz functions for some commonly used differential operators. These Trefftz functions are then used to construct boundary particle method for solving inhomogeneous problems with the b...
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The boundary knot method （BKM） is a truly meshless boundary-type radial basis function （RBF） collocation scheme, where the general solution is employed instead of the fundamental solution to avoid the fictitious o...
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The boundary knot method （BKM） is a truly meshless boundary-type radial basis function （RBF） collocation scheme, where the general solution is employed instead of the fundamental solution to avoid the fictitious outside boundary of the physical domain of interest. In this study, the BKM is first used to calculate the free vibration of free and simply-upported thin plates. Compared with the analytical solution and ANSYS （a commercial FEM code） results, the present BKM is highly accurate and fast convergent.
The boundary particle method(BPM)is a truly boundary-only collocation scheme,whose basis function is the high-order nonsingular general solution or singular fundamental solution,based on the recursive composite multip...
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The boundary particle method(BPM)is a truly boundary-only collocation scheme,whose basis function is the high-order nonsingular general solution or singular fundamental solution,based on the recursive composite multiple reciprocity method(RC-MRM).The RC-MRM employs the high-order composite differential operator to solve a much wider variety of inhomogeneous problems with boundary-only collocation nodes while significantly reducing computational cost via a recursive *** this study,we simulate the Kirchhoff plate bending problems by the BPM based on the *** results show that this approach produces accurate solutions of plates subjected to various loadings with boundary-only discretization.
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