In connection with improvement of public welfare, coming to the fore are requirements enabling comfortable living, which primarily depends on conditions of indoor air environment. This article provides arguments to suggest that, during reconstruction and overhaul of residential buildings, natural ventilation systems, failing to provide the required air exchange, need to be replaced with hybrid ventilation systems, allowing to maintain stable ventilation in existing multi-storey buildings throughout the year and involving minor capital and operating costs. Based on the example of a typical nine-storey residential building, two variations of hybrid ventilation have been developed: containing an ejector and roof fans, with economic feasibility of using both determined.

Keywords: microclimate quality, air exchange, natural ventilation, hybrid ventilation, an ejector, a roof fan, economic feasibility

This work investigated the influence of the type of vertical switching on the level of thermomechanical stresses and temperature deformation in a three-dimensional microassembly. Three microassembly models with the most common types of vertical connections were considered: solder balls in the package holes, metallized holes in the package, and end-switching tracks. For each of the three models, the effect of the sealing compound parameters on the thermomechanical load was additionally investigated.

Keywords: microassembly, packaging, electronic component base, three-dimensional integration, vertical switching, thermomechanical stress, thermomechanical deformation, thermal coefficient of linear expansion, thermomechanical modeling

One of the current tasks of operation of the linear part of the main pipelines is an adequate assessment of the degree of risk of pipe defects. There are several approaches to its solution and a set of calculation methods that take into account the specifics of the operation of main oil and gas pipelines. One of the main performance criteria of pipelines is their durability. The article describes a developed software product that allows you to automate the calculation of the maximum service life of a pipeline with a defect according to the chosen method.

Keywords: main pipelines, reliability, defects, strength, durability, program, calculation method, service life