The aim of this study is to evaluate the environmental and economic efficiency of using hydrogen-natural gas mixtures in existing fuel systems. The work is based on a stoichiometric calculation of emissions and a comparative cost analysis. It was found that the linear relationship between the hydrogen content and CO₂ emission reduction allows for a 30% reduction for a mixture containing 30% vol. H₂. Water vapor emissions are also reduced by 15%, which is explained by the difference in the combustion stoichiometry of methane and hydrogen. The article substantiates the economic feasibility of this technology when using inexpensive hydrogen produced locally, for example, through waste recycling.

Keywords: gas, natural gas, hydrogen, greenhouse gases, gas mixture, carbon dioxide

Building objects experience various kinds of impacts that can cause deformations of structural elements - deflections, integrity violations, complete destruction of individual elements, etc. Timely detection of deformations and monitoring of their dynamics is the most important element of the safe operation of buildings and structures. The task of monitoring cracks in building structures is to record changes in cracks in order to monitor their technical condition. As a result of monitoring, decisions are made on the further operation of the facility, the need for repair measures, and the elimination of factors affecting the development of cracks. The use of beacons makes it possible to monitor the behavior of deformations of building structures. For the simplest observations, gypsum and point beacons can be used, for more detailed observations, clock-type beacons and plate beacons can be used. Electronic beacons enable detailed automated monitoring of changes.

Keywords: crack, beacon, gypsum beacon, lamellar beacon, sentry beacon, point beacon, crack opening width

One of the problems when storing large amounts of data is a rational choice of media. In this paper we evaluated the possibility of using magnetic tape, CD, DVD, Blu-ray discs, hard disk drives, drives to flash memory (SSD) for storage of large volumes of data with respect to reliability, performance,.cost and high-speed storage. The analysis showed that solid state drives can be used in case of the need for ultra-fast access to live data. The hard disk drive can be used as primary storage devices for storing operational data. DVD and Blu-ray library can be used for archival storage medium volumes (tens of terabytes). Tape libraries can be used to store very large volumes of data (terabytes or more). The lowest cost of storing 1 GB of data is $ 0.03 when you use tape libraries. The most expensive storage 1 GB solid state drive ($ 0.85).

Keywords: storage devices, data storage, storage drive