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The Gyldén–Meshcherskii Problem (GMP) extends the classical two-body problem of Newton and Kepler by considering time-varying gravitating masses, an important extension of the two-body problem for modeling cometary motion and cosmological phenomena. In this paper, we consider the GMP in a specialized setup, the setup of gauge theory. We show that the variational equations, modeling the effect of the mass time variation on the orbital elements, can be derived by fixing a gauge of a particular form that is different from the Lagrange gauge. Thus, the orbital elements modeling the effect of a time-varying secondary mass are non-osculating. This implies that the trajectory of a celestial body whose mass is continuously changing cannot be approximated by a series of Keplerian orbits. Finally, we provide the first-order averaged equations written in terms of non-osculating elements.  相似文献   
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This research was aimed at obtaining a closed control system. This was achieved by placing all the technological processes providing for human vital activities within the hermetically sealed space, and by transferring the entire control and guidance of these processes to people inhabiting the system. In contrast to existing biological life support systems, man has been included not only as a participant of metabolism, but as an operator who is the central figure in collecting information, making decisions and controlling all technological processes. To tackle this problem, the "BIOS-3" experimental complex was created for performing long-term experiments using different structures of biological life-support system. The experiment lasted six months and consisted of three stages. During the first stage the system was comprised of two equivalent phytotrons with the culture of wheat and an assortment of vegetable plants, and the living compartment. At the second stage, one of the phytotrons was removed while a compartment of chlorella cultivators was introduced. The third stage differed from the second, the former using wheat phytotron and the latter employing phytotron with an assortment of vegetable cultures. Three men inhabited the system simultaneously. The experiment demonstrated that a biological life support system controlled autonomously from the inside is feasible within a small confined space. However, immunological and microbiological research shows, that the medium created by the system is not fully adequate for man. In conclusion, some prospects have been outlined for further studies of biological life support systems.  相似文献   
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