abstract this study uses gravity model to examine the most important determinants of was agricultural trade. to this aim, import and export statistics of iran agricultural products for the period 1380 to 1387 was provided from iran customs organization and other information was obtained from different internet bases. random effects estimating and hausman test ratio result in fixed effects model...

With the technological advancements in gravity gradiometry instrumentation, there is a need for understanding both the information content of modern gravity gradiometry data relative to traditional gravity data, and for developing processing and interpretation tools that assess the myriad of measured gradient components and information they contain. The Kauring Airborne Gravity Gradiometry Test...

The 3D correlation imaging for gravity and gravity gradiometry data provides a rapid approach to the equivalent estimation of objective bodies with different density contrasts in the subsurface. The subsurface is divided into a 3D regular grid, and then a cross correlation between the observed data and the theoretical gravity anomaly due to a point mass source is calculated at each grid node. T...

The choice of global geopotential model used in remove-restore technique for determination of regional quasigeoid from gravity data may affect the solution, in particular when the accuracy is supposed to reach a centimetre level. Global geopotential model plays also an important role in validating height anomalies at GPS/levelling sites that are used for the estimation of the external accuracy ...

Applicability of the weighting function method to gravity problems is discussed as compared with the exact method. The merits of the weighting function method are its simplicity and rapidity of computation, particularly in three-dimensional problems. For local geological problems, the weighting function method can be used for the gravity calculation with sufficient accuracy when the structure i...