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The tasks related to the efficient operation and maintenance of the power equipment in a working condition are considered. In the work, a model is built and a method is proposed for optimizing the intensity of performance indicators, which does not take into account the structure and with instant indexing of failure. At this stage, a lower estimate is obtained for the minimum average unit costs, taking into account the residual resource of the elements of such a system. This makes it possible to provide the required level of emergency repair frequency. The collection and accumulation of such information is in demand when planning subsequent preventive restorations of elements and equipment of electric power enterprises.

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We completely solve the Hayat-Legrand-Wang-Zieschang problem of listing all minimal Seifert manifolds (in the sense of degree 1 maps).Keywords: Seifert manifold, degree of a map § 1. Introduction and the Basic Theoretical FactsThe question of existence of a degree 1 map between two given Seifert manifolds M and P was posed in [1] and solved therein for all pairs M , P but for the case when M is a Seifert manifold with base "sphere" and three exceptional fibers or a Seifert manifold with base "torus" and one exceptional fiber and P is the dodecahedral space S 3 /P 120 (the Poincaré homology sphere). In this article, using the method for calculation of the degree of a map which was proposed by Hayat-Legrand, Matveev, and Zieschang, we study the problematic cases and show that none leads to degree 1 maps.