In this paper we present the design of tow robust nonlinear controllers for two mechanical problems of rejecting disturbances such as eccentricity and friction compensation. In the eccentricity compensation problem, the considered disturbances are here assumed to be produced by eccentricity in mechanical systems and drives, the frequency and amplitude of this disturbance is unknown. The objecti...

For a vertex v and a (k−1)-element subset P of vertices of a graph, one can define the distance from v to P in various ways, including the minimum, average, and maximum distance from v to P . Associated with each of these distances, one can define the keccentricity of the vertex v as the maximum distance over all P , and the k-eccentricity of the set P as the maximum distance over all v. If k =...

The extrasolar planets discovered to date possess unexpected orbital elements. Most orbit their host stars with larger eccentricities and smaller semi-major axes than similarly sized planets in our own solar system do. It is generally agreed that the interaction between giant planets and circumstellar disks (Type II migration) drives these planets inward to small radii, but the effect of these ...

The inclination of low-eccentricity orbits is shown to significantly affect the orbital parameters, in particular, the Keplerian, nodal precession, and periastron rotation frequencies, which are interpreted in terms of observable quantities. For the nodal precession and periastron rotation frequencies of low-eccentricity orbits in a Kerr field, we derive a Taylor expansion in terms of the Kerr ...

The influence of lateral asymmetry on the electronic structure and optical transitions in elliptical strained InAs nanorings is analyzed in the presence of a perpendicular magnetic field. Two-dimensional rings are assumed to have elliptical inner and outer boundaries oriented in mutually orthogonal directions. The influence of the eccentricity of the ring on the energy levels is analyzed. For l...

Backscattered energy from a medium with nearly constant velocity measured by an omnidirectional source-sensor comes from spherical shells centered at the source-sensor location. If source and sensor locations differ, the energy comes from ellipsoidal shells. To image the scattering potential or reflectivity of the medium, backscattered energy must be projected onto ellipsoids with a weighting f...

The eccentricity of a vertex is the maximum distance from it to another vertex and the average eccentricity ecc(G) of a graph G is the mean value of eccentricities of all vertices of G. In this paper we resolve five conjectures, obtained by the system AutoGraphiX, about the average eccentricity and other graph parameters (independence number, chromatic number and the Randić index), and refute t...

conclusions we found that ei and qp/qs ratio are significantly and positively associated and qp/qs ratio can be easily estimated by measuring ei in secundum type asd patients. background one of the inclusion criteria for applying atrial septal defect (asd) closing procedure is an increased pulmonary-to-systemic blood flow ratio (qp/qs). eccentricity index (ei) is associated with ventricular dys...