In this paper, we solve the problem of estimating the parameters of a system of ordinary differential equations from observations on a short interval of argument values. By analogy with linear regression analysis, a sufficiently large number of observations are selected on this segment and the values of the functions on the right side of the system and the values of the derivatives are estimated. According to the obtained estimates, unknown parameters are determined, using the differential equations system. The consistency of the estimates obtained in this way is proved with an increase in the number of observations over a short period of argument values. Here, an algorithm for estimating parameters acts as a system. The error of the obtained estimate is an indicator of its quality. A sequence of inaccurate measurements is a random process. The method of linear regression analysis applied to an almost linear regression function is used as an optimization procedure.

T. The construction of discrete ergodic Markov processes with continuous time is using to construct a mathematical model of a queuing system with a variable structure. This model is a combination of several models of queuing systems. The set of states of the combined system is a combination of sets of states of the combined systems, unlike classical queuing systems, in which the set of states of the system is a direct product of the sets of states of the combined systems. The transition intensities between the states of different systems are choosing so that the limit distribution of the combined system is a mixture of the limit distributions of the combined systems with different weights determined by the introduced transition intensities. As a result, the process of functioning of the combined system is obtaining by switching intensities corresponding to different combined systems at certain points in time.

The paper considers a method for introducing additional transient intensities into the queuing system, creating a uniform stationary distribution over a set of states. It is basing on the selection of states in which the sum of the input intensities is not equal to the sum of the output intensities. New transitional intensities are introducing between these states, which transform these inequalities into equalities. On the one hand, such a transformation is connecting with the procedure for clearing the service system of customers. On the other hand, this procedure to some extent simulates the process of transferring information from short-term memory to long-term memory. In this paper, the procedure for introducing new elements into the graph of transient intensities is understood as management in the queuing system. The algorithms used in the work for introducing new transient intensities are closely relating to the procedure for determining the maximum flow in the network and to the northwest angle method in linear programming.