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PRELIMINARY REMARKSA geometric pattern of integral curves describing the evolution of the elements of elliptic orbits under the action of gravitational perturbations from external bodies was studied in great detail in a series of papers by V.I. Prokhorenko (see [4][5][6]). It corresponded to the solution of doubly averaged system of evolution equations [1] (in the following, "the solution of averaged Hill problem"). Comparing this pattern with the pattern of stream lines of two-dimensional eddy motion of a fluid in a circular domain [7,8] we can see a close resemblance. More detailed analysis allows one to establish not only geometric but also kinematic similarity of these patterns. This suggests that there exists an analogy between two mentioned physical phenomena, different in their nature. A proof of the existence of such an analogy and an analysis of some of its significant consequences would allow one to supplement and widen the known celestial-mechanical facet of the problem.The geometric studies are based on the analytical solutions to an approximate system of equations describing the motion of point P of zero mass in the field of gravitation of central point S with mass M under the action of gravitation perturbations of the third point J with mass M 1 . Let us present some fragments of geometric representation of solutions [1] proposed in [4][5][6]. We introduce a spherical frame of reference O ε i ω , where the radius is ε = 1 -e 2 (0 ≤ ε ≤ 1) , where e is eccentricity, i (colatitude) is the inclination of the orbit (0° ≤ i ≤ 180°), and ω (longitude) is the argument of the pericenter ( 0° ≤ ω ≤ 360° ). Angular elements are measured with respect to the plane of the orbit of a perturbing point.In the corresponding Cartesian coordinate system OXYZ the plane OXY coincides with the plane i = 90° , plane OXZ corresponds to the values ω = 0°, ω = 180° , and plane OYZ corresponds to values ω = 90°, ω = 270° , and the OX axis lies in the meridian plane ω = 0° . The range of possible values of parameters ε , i , and ω in this frame of reference is limited by the spherical surface of unit radius. The region of evolution of orbital elements determines the following first integrals obtained in [1]: c 1 = ε cos 2 i ; c 2 = (1 -ε )(2/5 -sin 2 ω sin 2 i ). Let us use as parameters the integral constants c 1 (0 ≤ c 1 ≤ 1) and c 2 (-0.6 ≤ c 2 ≤ 0.4) determined by initial values of the orbital moments ε 0 , i 0 , and ω 0 : c 1 = ε 0 cos 2 i 0 ; c 2 = (1 -ε 0 )(2/5 -sin 2 ω 0 sin 2 i 0 ). An example of integral curves corresponding to the solution [1] to averaged Hill problem at c 1 = 0.4 is presented in the projection onto the OXY plane in Fig. 1. When c 2 > 0, the orbit evolution has a rotational character (it is determined by closed curves going around the center of the circle). When c 2 < 0, the evolution has libration character (determined by closed curves located eccentrically).Above we wrote about the similarity of the integral curves of a solution of the Hill problem and the stream lines for some class of motions of...

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In this paper, the authors propose a five-step approach to the problem of identifying semantic correspondences between attributes of two database schemas. It is one of the key challenges in many database applications such as data integration and data warehousing. The authors' research is focused on uninterpreted schema matching, where the column names and column values are uninterpreted or unreliable. The approach implements Bayesian networks, Pearson's correlation and mutual information to identify inter-attribute dependencies. Additionally, the authors propose an extension to their algorithm that allows the user to manually enter the known mappings to improve the automated matching results. The five-step approach also allows data privacy preservation. The authors' evaluation experiments show that the proposed approach enhances the current set of schema matching techniques.