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In this work, a nonminimal coordinate representation of tensegrity structures with explicit constraints is introduced. A method is proposed for representation of results on tensegrity structures in sparse models of generalized forces, providing advantages for code generation for symbolic or autodifferentiation derivation tasks, and giving diagonal linear models with constant inertia matrices, allowing one not only to simplify computations and matrix inversions, but also to lower the number of elements that need to be stored when the linear model is evaluated along a trajectory.

At the oil production wells of Gazpromneft Vostok LLC, with the problem of scale formation, there was made an assessment of the possibility of using an encapsulated scale inhibitor. According to the test results, it’s found that the reagent provides effective protection of production wells from salt deposits. There are noted such a positive aspects of this inhibitory protection technology as the absence of corrosive effects on downhole equipment, the possibility of quick organization of well protection, not using metering equipment, independence from the infrastructure and the convenience of loading capsules during workover. A comparative analysis with the classical inhibitor protection with liquid scale inhibitors has been carried out. It is shown that with a water flow rate of up to 38 m3 / day, the use of encapsulated reagents is more cost effective. The limitations of the application of the technology are noted – the difficulty in carrying out additional loading of the reagent into the well without lifting the downhole equipment, application in horizontal and directional wells.

Today hydraulic fracturing is proved to be the most reliable and effective method of well stimulation. Specialists of NGDU are performing hydraulic fracturing efficiently, taking into account the quality of wells selection, introducing mode of treatment in order to provide an optimal geometry of fracture and get the highest production index from every well. In spite of the fact that repeated hydraulic fracturing is widely spread and used, all works are narrow directed. Considering either treatment results or, vice versa, describe process design. In this work we tried to identify treatment mode dependence, which allows generating required geometry of the fracture in accordance with different factors and then, estimate obtained results of well production increase and incremental ultimate recovery. Refractured wells were chosen for qualitative assessment of hydraulic fracturing to estimate correctness of project modes and treatment result more exactly. It will also allow improving efficiency not only from refracturing, but also from first treatments.