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The effect of non Heisenberg four spin ring exchange on the superconducting transition temperature in strongly correlated electron systems is studied. It is shown that the ring exchange can significantly suppress the contribution of the Heisenberg exchange to superconducting pairing.

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The article considers the inland waterways (IW) within the international transport corridors as multiphase systems of mass service (SMS) and shows the distinction in calculation of the important indicator of system efficiency - the average total waiting time of vessel service in the serving subsystems, the application of genetic algorithms to increase the efficiency of reloading processes.