System approach to research processes of technological adjustment of machine and tractor units

A substantive interpretation of the main categories of the system approach is formulated in relation to the semantics of the operation of mobile agricultural units from the standpoint of ensuring the technological reliability of the production of field mechanized work by improving the methods and means of measuring control of the state of machine and tractor units and evaluating the parameters of functional diagnostics under shift time conditions. A structural diagram of the systemic image of the production of field mechanized work is proposed, which makes it possible to clarify the hierarchical levels of movement of concepts in the field of managing the state of a complex technical system during the operation period, to highlight the object of research and establish its system elements and connections with the operating environment. The business logic of the implementation of the basic operations of the system of technological adjustment of machine-tractor units to ensure the quality of the technological operation when used for its intended purpose is presented. The theoretical significance of the work is associated with the development of a systematic understanding of the main objects of the processes of machine use in agriculture. The applied and practical significance of the work is confirmed by new technical solutions implemented in projects and organizational and technical documents of an industry scale. The results of the work can be useful both for researchers of the processes of machine-use in agriculture, and for practitioners-subjects of small and medium-sized agribusiness, as well as in organizing the transfer of knowledge of the agro-engineering direction to specialists in agricultural production.

Datafied mobile markets: Measuring control over apps, data accesses, and third-party services

The increasing use of mobile applications (apps) has turned data harvesting, mining, and distribution into commercial as well as functional backbones of mobile communication. Acknowledging that contemporary markets for mobile communication are increasingly datafied, this article maps and discusses how infrastructures for mobile datafication are controlled. It combines perspectives from critical data studies, political economy of communication, and app studies in an empirical analysis of the 500 most downloaded apps in the Google Play store (November 2020). Focusing on control over and ownership in the three interdependent markets for apps, data accesses, and third-party services, the analysis documents, confirms, and explains established power structures and sheds light on the mobile datafication processes that frame the use of apps and commodification of users. As such, it provides an empirical baseline for future monitoring, and ultimately regulation, of mobile app ecosystems.

Development of a generalized mathematical model of static error electromechanical measuring equipment

To keep military equipment fit for use, carry out maintenance activities, an important and integral part of which is metrological service. The effectiveness of metrological services depends on the completeness of the coverage of the monitored parameters, frequency and reliability of their measuring control. The most common, at present, when controlling the parameters of military equipment are electromechanical measuring equipment. The main metrological characteristic of electromechanical measuring instruments in a static measurement mode is the nominal calibration characteristic. During operation, the calibration characteristic of electromechanical measuring instruments, under the influence of various factors, has deviations from the nominal, which leads to an instrumental static error. The article deals with the applied aspects of assessing the static error of electromechanical measuring equipment, which is expressed through the sensitivity or static transmission coefficients of measuring transducers. Based on the results of the analysis, a generalized mathematical model of the relative static error of electromechanical measuring equipment for various structural schemes of connecting measuring transducers was obtained. It is proposed to apply a generalized mathematical model to assess the relative static error of electromechanical measuring instruments (with various structural schemes) during their operation. The use of an updated static error will allow to refine the calibration characteristics of electromechanical measuring instruments, which in turn will lead to obtaining reliable information about the state of military equipment during metrological maintenance and immediately before use.

Temperature development of selected materials in a reduced model – experimental test

The work is focused on an experimental test of temperature development in a scale model. Various types of combustible materials were used in the test in combination with the spruce wood. The work points to the influence of the fuel source on selected parameters of a fire in an enclosed space. The course of a fire is influenced by various factors. The course of a fire in an enclosed space differs from the course of a fire in an open space. As a part of the overall development of the fire, the temperature of the fire is affected. Therefore, one can state that the parameters affecting the development of an internal fire also have a direct effect on the temperature development. The main goal of this work is to compare different types of materials in terms of the properties they manifest during a fire. The practical part contains the analysis of the materials used in the experiment. Description of the scale model and of the measuring control panel are the content of another part of the work. In the end there is a comparison of the individual temperature curves.

Применение методов неразрушающего контроля качества при обследовании состояния систем молниезащиты пожаро-взрывоопасных объектов

The issues of non-destructive testing carried out during the inspection of the state of lightning protection systems for fire and explosion hazardous facilities, are considered. Including the objects of the main oil and oil product pipelines were considered. It is indicated three types of tests have to be used: quantitative assessment of the necessary elements of the lightning protection system, visual and measuring control of the system elements using geometric and geodetic measurements, and measuring the electrical parameters of the elements of the lightning protection system. The features of control and measurements related to the calculation of protection zones against a direct lightning strike when using lightning rods of various types or their combinations are described. Examples of the estimation of the error in calculating the protection zones against a direct lightning strike are given.