Simulation of the interaction of the primary microwave converter with a control object based on the laws of geometric optics

In this article, the features of constructing a mathematical model of the interaction of the primary converter and the object of control are given. Also, a brief assessment of existing methods for controlling energy-loaded gearbox systems is given. Expressions approximating the amplitude characteristic are given. The equation is given to take into account the directional pattern in the construction of the model

FEATURES CONSTRUCTING MATHEMATICAL MODELS OF PRIMARY CONVERTERS IN THE CONTROL SYSTEM PARAMETERS COGWHEELS

Разрабатывается бесконтактный радиоволновой метод контроля рабочего состояния зубчатого колеса, основанный на обработке в реальном времени сигналов, полученных после детектирования отражённого от зубцов колеса зондирующего излучения СВЧ диапазона. Представлены графики зависимости амплитуды сигнала от расстояния между торцом излучающего волновода и контролируемой поверхностью, полученные экспериментальным путём. Данные зависимости были аппроксимированы степенными полиномами

Reaction rate for two--neutron capture by 4^4He

Recent investigations suggest that the neutrino--heated hot bubble between the nascent neutron star and the overlying stellar mantle of a type--II supernova may be the site of the r--process. In the preceding $\alpha$--process building up the elements to $A \approx 100$, the $^4$He(2n,$\gamma$)$^6$He-- and $^6$He($\alpha$,n)$^9$Be--reactions bridging the instability gap at $A=5$ and $A=8$ could be of relevance. We suggest a mechanism for $^4$He(2n,$\gamma$)$^6$He and calculate the reaction rate within the $\alpha$+n+n approach. The value obtained is about a factor 1.6 smaller than the one obtained recently in the simpler direct--capture model, but is at least three order of magnitude enhanced compared to the previously adopted value. Our calculation confirms the result of the direct--capture calculation that under representative conditions in the $\alpha$--process the reaction path proceeding through $^6$He is negligible compared to $^4$He($\alpha$n,$\gamma$)$^9$Be.Comment: 13 pages, 4 postscript figures, to appear in "Zeitschrift f. Physik A", changed internet address and filename, the uuencoded postscript file including the figures is available at ftp://is1.kph.tuwien.ac.at/pub/ohu/twoneutron.u