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The paper examines the heat supply system of the building of the educational building of the National University "Odesa Polytechnic" in intermittent mode. Intermittent heating mode is quite widely used to save costs mainly for autonomous building heating systems. The application of Pontryagin's maximum principle to solving the problem of the optimal load of the heating system during the morning on-top of the room is considered. At the same time, a corresponding optimality criterion is also added. With regard to the intermittent-frequent heating mode, the task of optimal control is formulated as the determination of the optimal control effect during the period of morning heat to achieve a comfortable air temperature in the room tk. The criteria for the study of the efficiency of the load modes of the autonomous heating system in intermittent mode have been determined. The task of optimizing the load modes of the heating system is formulated. Based on the results of solving the optimization problem on the mathematical model, the corresponding daily load schedules of the heating system optimal in terms of energy efficiency were obtained. The effect of limitations on the thermal power of the heating system on the effectiveness of the morning heating of the room in the intermittent heating mode was investigated. The study was performed based on the maximum average daily load of the heating system at a calculated outside air temperature of -15 ºС. Options for using thermal insulation to improve the efficiency of the morning heating of the room are considered. The use of combined thermal insulation of the building (external and internal) is proposed as a way to increase the efficiency of the intermittent heating mode while limiting the thermal power of the heating system. Energy savings and efficiency of the intermittent heating mode compared to round-the-clock heating were evaluated. [ABSTRACT FROM AUTHOR]

The paper proposes a methodology for mathematical modeling of the step-by-step development of nodes and transport routes in a hierarchical network with multicommodity discrete flows of correspondence based on solving the problems of optimizing its structure and distribution of flows. As a rule, such networks consist of a decentralized trunk network and networks in the internal service areas of trunk nodes. In a multicommodity network, each node can exchange correspondence (products, goods, cargo, messages) with other nodes. Correspondence is characterized by a source node, a sink node, and a quantity, which for data transmission networks is given by the number of bytes, kilobytes, etc., and for transport networks by the number of cargo units in a package of uniform size. In the trunk network, all correspondence is transmitted via communication channels or transported in vehicles in transport blocks of a given size (capacity, volume). The authors considered the main postulates of generating a mathematical model of the perspective development of the trunk network and gave a method of mathematical modeling of the step-by-step development of nodes and transport routes, which includes, for each stage of development, the forecasting of data and network parameters, solving the problem of packing correspondence and choosing the structure of the network, solving the problem of distribution and routing of flows of transport blocks. [ABSTRACT FROM AUTHOR]