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The article proposes a patent protected proprietary technique for managing lean mining and use of mineral resources of Ukraine on the example of non-metallic minerals for construction. Proposed solution of the problem on the basis of the technological relationship between the production processes and the lean use of production products with forecasting the development of the extractive industry is new. Ukraine has significant reserves of rocks suitable for mining of building stone, construction sands and expanded clay. Analysis of official statistics on the volume of mining of construction stone, construction sand and expanded clay showed that over the analyzed period, which was 12 years, there were fluctuations in both the volume of production and the rate of their growth. Approximation and smoothing of rates of growth of volumes of extraction of the investigated nonmetallic minerals for construction of a polynomial function with use of a trend line is carried out. The analysis of the obtained results showed that the fluctuations of the investigated indicators of extraction of nonmetallic minerals for construction have a periodic, cyclical nature, correlate with each other and are related to the general economic state of the construction industry and the country. It is proved that it is possible to solve the problem of lean use of minerals by more balanced extraction of minerals, namely, establishing a correlation between extraction and use volumes. To predict the development of the industry, the author suggests using multifactorial economic and mathematical model for forecasting the development of complex systems. It is proved that such a model will allow controlling the volumes of mining of technologically related minerals in interdependence on the volumes of their use.

The objective of the study is to develop favourable environment’s assessment and forecasting methodology for social entrepreneurship development in market economies. Methodology. Econometric method to build regression model of country’s favourable conditions for social entrepreneurs’ relationship to its determinants is applied in the research. The research is based on previously developed multi-step algorithm: statistical data systematization, regression model building and relevant variables’ selection, new regression model building excluding insignificant variables, type of regression model setting and scenario forecasting. The type of regression model that best describes the correlation nature has been determined. Scenario forecasting of country’s favourable conditions’ changes for social entrepreneurs based on “state policy support of social entrepreneurship development” implementation has been carried out. Three scenarios of social entrepreneurship development have been designed: pessimistic, inertial (basic) and optimistic. Research data comes from statistical databases of “The best countries to be a social entrepreneur” poll conducted by the Thomson Reuters Foundation in 2016 and 2019. Study results revealed that country’s favourable conditions for social entrepreneurs’ development are mostly affected by government policy support and investment access which form particular environment aimed at successful economic performance inside a country. Practical implications. Assessment and forecasting of favourable development of social entrepreneurship reveals its strengths and weaknesses that need to be improved through implementation of centralized “government policy for the development of social entrepreneurship.” This enables countries not only to keep scores of “the best country for the development of social entrepreneurship”, but also to improve their position in the future. Value/originality. Nowadays social entrepreneurship is becoming a tool to overcome current challenges and preserve human potential by the resurgence of innovative forms of business. One of the ways to achieve the objective is proposed in our study.

The study of social entrepreneurship and the assessment of its necessity caused by MANAGEMENT AND ENTREPRENEURSHIP: TRENDS OF DEVELOPMENT ISSUE 1 (11), 2020114 countries with similar level of economic development to prove the relevance of social entrepreneurship implementation as innovation form of business, to identify the terms of its advantageous development in the long period and to build the strategy of social enterprises operations and their management.

Работа посвящена минимизации при пуско-тормозных режимах (посредством энергосберегающих траекторий изменения скорости и оптимальных длительностей времени разгона и торможения) электропотребления троллейбуса, снабженного частотно-регулируемым асинхронным двигателем и суперконденсаторным накопителем генерируемой энергии. При проведении исследований использовались методы энергетического баланса, математического анализа и имитационного компьютерного моделирования. Определен вид траекторий скорости при разгоне и торможении троллейбуса, соответствующих минимизации общего и удельного потребления энергии троллейбусом. Выявлено наличие оптимальных длительностей времени разгона и торможения, обеспечивающих минимизацию общего потребления энергии троллейбусом в пуско-тормозных режимах. Предложены аналитические зависимости для расчета общего и удельного потребления и генерации энергии троллейбусом, содержащим суперконденсаторный накопитель генерируемой энергии. Применительно к исследуемым различным (линейной, параболической и квазиоптимальной) траекториям изменения скорости троллейбуса, получены расчетные соотношения для минимально возможных значений времени его разгона и торможения, исходя из допустимых для троллейбуса максимальных ускорения и замедления в указанных режимах. Исследованы электромеханические и энергетические процессы в троллейбусе, тяговом двигателе и суперконденсаторе при пуско-тормозных режимах. Выполнены расчеты общего и удельного электропотребления троллейбусом при движении между соседними остановками с упомянутыми разными видами траекторий скорости в пускотормозных режимах. Практическое использование результатов исследований позволяет уменьшить до минимально возможных значений общее или удельное потребление энергии троллейбусом при его движении. Ключевые слова: троллейбус, тяговый асинхронный двигатель, частотное регулирование, электропотребление, оптимизация. ОПТИМІЗАЦІЯ ЕЛЕКТРОСПОЖИВАННЯ ТРОЛЕЙБУСА З ТЯГОВИМ ЧАСТОТНО-РЕГУЛЬОВАНИМ АСИНХРОНИМ ДВИГУНОМ І СУПЕРКОНДЕНСАТОРНИМ НАКОПИЧУВАЧЕМ ЕНЕРГІЇ, ЩО ГЕНЕРУЕТЬСЯ ЕЛЕКТРОМЕХАНІЧНІ СИСТЕМИ, МЕТОДИ ОПТИМІЗАЦІЇ ТА МОДЕЛЮВАННЯ Електромеханічні і енергозберігаючі системи. Випуск 1/2019 (45) 24 cal and energetic processes in a trolley bus, a traction engine, and a supercondensator under commissioning and braking conditions were investigated. Calculations of total and specific power consumption by a trolleybus were carried out when moving between adjacent stops with the above-mentioned different types of speed trajectories in the start-braking regimes. Practical value. Practical use of research results allows to reduce to the minimum possible values the total or specific energy consumption of a trolleybus during its movement. Figures 7, tables 6, references 17.