Применение быстрого автоматического дифференцирования при нахождении испарения с поверхности почвы

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В.В. Дикусар, С.В. Засухин
54 ISSN 1812-3368. Вестник МГТУ им. Н.Э. Баумана. Сер. Естественные науки. 2016. № 6
Засухин Сергей Владимирович — аспирант Московского физико-технического инсти-
тута (государственного университета) (Российская Федерация, 141700, Московская обл.,
Долгопрудный, Институтский переулок, д. 9).
Просьба ссылаться на эту статью следующим образом:
Дикусар В.В., Засухин С.В. Применение быстрого автоматического дифференцирования
при нахождении испарения с поверхности почвы // Вестник МГТУ им. Н.Э. Баумана.
Сер. Естественные науки. 2016. № 6. C. 42–55. DOI: 10.18698/1812-3368-2016-6-42-55
APPLICATION OF FAST AUTOMATIC DIFFERENTIATION
IN THE SOIL SURFACE EVAPORATION PROBLEM
V.V. Dikusar1
S.V. Zasukhin2
1 Dorodnitsyn Computing Centre, Federal Research Centre Computer Science
and Control, Russian Academy of Sciences, Moscow, Russian Federation
2 Moscow Institute of Physics and Technology (State University), Dolgoprudny,
Moscow Region, Russian Federation
Abstract Keywords
Evaporation from the soil surface is an important and often
hard-determined part of modeling the vertical water transfer
in soil. The study considers the problem of determining
evaporation and formulates it as an optimal control prob-
lem. The objective function is mean-square deviation of
modeled values of soil moisture at various depths from some
prescribed values. We found the numerical solution by the
steepest descent method, and we calculated the gradient of
the objective function by formulas of fast automatic differ-
entiation (FAD). Moreover, we applied FAD method to
estimate the sensitivity of soil moisture at various depths to
changes of evaporation. The findings of the research made it
possible to determine the effective subsurface soil layer in
which it is advisable to compute the objective function.
Numerical results showed that this subsurface soil layer
determination has accelerated the convergence of finding
solutions process and has reduced its run time
Vertical water transfer in soil,
objective function, steepest descent
method, fast automatic differentia-
tion method
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