Unification of the global vertical datum has been a key problem to be solved for geodesy over long period, and main challenge unifying system is determine geopotential value W0 geoid calculate offset between local W0. The can calculated using grid mean sea surface (GMSS) data model (GGM). In this study, GMSS was measured with adjustment methods 24 years merged multi-satellite altimetry data. Ha...

In this paper, the solution of the evolutionaryfourth-order in space, Sivashinsky equation is obtained by meansof homotopy perturbation method (textbf{HPM}). The results revealthat the method is very effective, convenient  and quite accurateto systems of nonlinear partial differential equations.

In this paper the Bagley-Torvik equation as a prototype fractional differential equation with two derivatives is investigated by means of homotopy perturbation method. The results reveal that the present method is very effective and accurate.

In this paper a closed form solution for one-dimensional magnetothermoelastic problem in a functionally graded material (FGM) hollow sphere placed in a uniform magnetic field and temperature field subjected to an internal pressure is obtained using the theory of magnetothermoelasticity. Hyper-geometric functions are employed to solve the governing equation. The material properties through the g...

in this study, the artificial neural networks (anns) and regression models were used to downscale the simulated outputs of the general circulation models (gcms). the simulated precipitation for 25.18 º n to 34.51 º n and 45 º e to 60 º e, geopotential height at 850 mb and zonal wind at 200 mb for 12.56° n to 43.25° n and 19.68° e to 61.87° e data sets as the predictors were extracted from echam...

A new seawater Boussinesq system is introduced, and it is shown that this approximation to the equations of motion of a compressible binary solution has an energy conservation law that is a consistent approximation to the Bernoulli equation of the full system. The seawater Boussinesq approximation simplifies the mass conservation equation to $ u 5 0, employs the nonlinear equation of state of s...

Determination of the geoid with a high accuracy is the main task among researchers in the geodetic community. Precise determination of a regional geoid is usually carried out combining a global geopotential model data with a set of point or mean terrestrial gravity anomalies measured in the region and some topographic information. In this research a primary Iranian gravimetric geoid model has b...

The high accumulation rate and negligible amount of melt at Eclipse Icefield (3017 m) in the Saint Elias Range of Yukon, Canada, allows for the preservation of a high-resolution isotopic and glaciochemical records valuable for reconstruction of climatic variables. Each of the three Eclipse ice cores have a well-constrained depth–age scale with dozens of reference horizons over the twentieth cen...

The GOCE (Gravity Field and Steady-State Ocean Circulation Explorer) has signifi cantly upgraded the knowledge on the Earth gravity fi eld. In this contribution the accuracy of height anomalies determined from Global Geopotential Models (GGMs) based on approximately 27 months GOCE satellite gravity gradiometry (SGG) data have been assessed over Poland using three sets of precise GNSS/levelling ...