Gravimetric quantities are commonly represented in terms of high degree surface or solid spherical harmonics. After EGM2008, such expansions routinely extend to spherical harmonic degree 2190, which makes the computation of gravimetric quantities at a large number of arbitrarily scattered points in space using harmonic synthesis, a very computationally demanding process. We present here the dev...

We present the latest developments on the number of (≤ k)-sets and halving lines for (generalized) configurations of points; as well as the rectilinear and pseudolinear crossing numbers of Kn. In particular, we define perfect generalized configurations on n points as those whose number of (≤ k)-sets is exactly 3¡k+1 2 ¢ for all k ≤ n/3. We conjecture that for each n there is a perfect configura...

reservoir models are initially generated from estimates of specific rock properties and maps of reservoir heterogeneity. many types of information are used in reservoir model construction. one of the most important sources of information comes from wells, including well logs and core samples. unfortunately well log and core data are local measurements that may not reflect the reservoir behavior...

This research explains airplane model with two vertical vibrations for airframe and landing gear system. The purpose of this work is to advance vibrational model for study of adjustable vibration absorber and to plan Proportional-Integration-Derivative approach for adapting semi active control force. The coefficients of this method are modified as stated by Bee multiobjective optimization using...

It is well established that the free-space Green's function can be recovered from the two-point cross-correlation function of a random noise field if the noise is white and isotropic. Ambient noise in the ocean rarely satisfies either of these conditions. However, a non-uniform spectrum could be pre-whitened by the application of a suitable filter but anisotropy cannot be so readily eliminated....