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В статье рассматриваются современные подходы к оценке раннего речевого развития детей первых лет жизни. Специальное образование, Issue № 4 (52), Pages 95-105

The article reveals the operational aspects of induction generator. Methods for stabilization of induction generator (IG) parameters under inverter excitation are investigated. The study was carried out using mathematical description and simulation modeling in MATLAB Simulink. The paper provides analysis of causes of generated voltage amplitude and frequency displacement when the loading condition and the rate vary. Due to the parametric resonance nature of IG self-excitation, the author introduces the expression that allows estimating the capacitor capacitance required to maintain the generation process, depending on the rotor speed of electric machine, load nature and rate. Based on the studies, it was proved that it is possible to stabilize the IG voltage parameters by maintaining the magnetizing circuit inductance Lm at the constant level., and realizing a control law close to U/f = const. The study proves that using the inverter together with the voltage regulator allows ensuring the quality of electricity corresponding to modern standards. The necessity of problem solving of the required quality of the voltage by the harmonic component for the exciter - inverter with PWM is shown. The prospects of the power generation system based on induction machine (IM) with a semiconductor frequency converter, which serves as an adjustable supplier of capacitive current for IM for autonomous objects, are substantiated. The use of semiconductor frequency converters makes it possible to provide high stability of the output voltage parameters and good speed of the mechatronic generation system with an asynchronous machine.

The scientific justification and development of the method for industrial synthesis of complex aluminates of alkaline earth metals is an innovative solution that determined several directions in the development of technology for complex processing of nepheline raw materials. It ensures the production of high-quality metallurgical alumina, the effective utilization of nepheline sludge and production of new types of multipurpose by-products. The modern development of these technical solutions is associated with ensuring the energy efficiency of the synthesis of hydrafed calcium carboaluminates (HCCA) and increasing the level of purification of aluminate solutions. The conditions for synthesizing HCCA with the use of calcareous materials of natural and technogenic origin have been experimentally determined, which makes it possible to isolate the average particle diameter as one of the determining factors of this process. The effect of the turnover of the hydrogarnet sludge on the removal of kinetic limitations in the process of deep desalination of aluminous solutions is theoretically justified. The conditions of a two-stage dosage of HCCA are experimentally determined. It is shown that the optimum ratio of the amount of the reagent supplied in the first and second stages is about 3: 2. At the same time, the maximum degree of precipitation of silica provides the production of aluminate solutions with a silicon module at the level of 95,000, which is achieved by using a HCCA synthesized based on chemically precipitated calcium carbonate in the processing of wastes from the production of mineral fertilizers. Научное обоснование и разработка способа промышленного синтеза сложных алюминатов щелочно-земельных металлов представляет собой инновационное решение, определившее целый ряд направлений в развитии технологии комплексной переработки нефелинового сырья. Это обеспечивает получение высококачественного металлургического глинозема, эффективную утилизацию нефелинового шлама и выпуск новых видов попутной продукции широкого назначения. Современное развитие этих технических решений связано с обеспечением энергоэффективности синтеза гидрокарбоалюминатов кальция (ГКАК) и увеличением глубины очистки алюминатных растворов. Экспериментально определены условия синтеза ГКАК с использованием известковых материалов природного и техногенного происхождения, что позволяет выделить средний диаметр частиц в качестве одного из определяющих факторов этого процесса. Теоретически обосновано влияние оборота гидрогранатового шлама на снятие кинетических ограничений в процессе глубокого обескремнивания алюминатных растворов. Экспериментально определены условия двухстадийной дозировки ГКАК. Показано, что оптимальное соотношение количества реагента, подаваемого на первой и второй стадии, составляет около 3:2. При этом максимальная степень осаждения кремнезема обеспечивает получение алюминатных растворов с кремниевым модулем на уровне 95000, что достигается при использовании ГКАК, синтезированного на основе химически осажденного карбоната кальция при переработке отходов производства минеральных удобрений. №231(3) (2018)

In the article, within the framework of the dynamic theory of elasticity, a mathematical model of the impact of seismic blast waves on rock mass is presented, including a working. The increase in the volume of mining operations in complex mining and geological conditions, taking into account the influence of the explosion energy, is closely connected with the analysis of the main parameters of the stress-strain state of the rock massif including a working. The latter leads to the need to determine the safe parameters of drilling and blasting operations that ensure the operational state of mining. The main danger in detonation of an explosive charge near an active working is a seismic explosive wave which characteristics are determined by the properties of soil and parameters of drilling and blasting operations. The determination of stress fields and displacement velocities in rock mass requires the use of a modern mathematical apparatus for its solution. For numerical solution of the given boundary value problem by the method of finite differences, an original calculation-difference scheme is constructed. The application of the splitting method for solving a two-dimensional boundary value problem is reduced to the solution of spatially one-dimensional differential equations. For the obtained numerical algorithm, an effective computational software has been developed. Numerical solutions of the model problem are given for the case when the shape of the working has a form of an ellipse. В статье в рамках динамической теории упругости представлена математическая модель воздействия сейсмовзрывных волн на массив горных пород, включающий выработку. Увеличение объемов добычи по-лезных ископаемых в сложных горно-геологических условиях с учетом влияния энергии взрыва тесно связано с анализом основных параметров напряженно-деформированного состояния массива горных пород, включающего выработку. Последнее приводит к необходимости определения безопасных параметров бу-ровзрывных работ, обеспечивающих эксплуатационное состояния горной выработки. Основную опасность при взрыве заряда взрывчатого вещества вблизи действующей выработки представляет сейсмовзрывная волна, характеристики которой определяются свойствами грунта и параметрами буровзрывных работ. Определение полей напряжений и скоростей смещений в массиве горных пород требует привлечения для своего решения современного математического аппарата. Для численного решения поставленной краевой задачи методом конечных разностей авторами построена оригинальная расчетно-разностная схема. Применение метода расщепления для решения двухмерной краевой задачи сводится к решению пространственно одномерных дифференциальных уравнений. Для полученного численного алгоритма разработана эффективная вычислительная программа. Приведены численные решения модельной задачи для случая, когда форма горной выработки представлена эллипсом. №4 (226) (2017)

One of the most important informational components of control systems is the data of the static load characteristics of each transformer of the substation. Currently, the evaluation of real static characteristics of the load is determined generally by the following methods: computational, analytical, passive and active experiments. These methods exhibit significant disadvantages regarding accuracy and cost rating and encounter plenty of parameters that are difficult to formalize (including climatic factors). The purpose of this work is to reduce electric power losses at 110/220 kV substations by implementation of a new control system for power transformers. This goal has been achieved by using a fuzzy controller in the structure of the control system for power transformers of 110/220 kV tie substations. The presented solution is multi-functional and can be extended to a wide class of power facilities. The results of the simulation of the transformer voltage regulation process, performed in the MatLAB application environment, showed that the implementation of a new fuzzy controller structure had improved the efficiency of the substation power control system in forecasting and management (compared to classical solutions based on regression and probabilistic models). Herewith, the most accurate accounting of consumer load, the maximum use of equipment at the substation for voltage regulation at the points of release and a significant reduction of active power losses at the tie substations 110/220 kV (up to 12,12%) compared to already known solutions were observed.

The problem of increase of the unit power on the shaft of an energy microturbine is of current interest. One of the problems is the small single unit power of microturbines, limited by the low capacity of gas-dynamic air bearings. The problem could be solved by replacing gas-dynamic bearings with hybrid ones with a higher load-bearing capacity. Hybrid bearings use self-aligning turning segments and forcing gas into the lubricating layer. The scientific result of the work is the method of designing grooves that distributes gas, the shape of which repeats the pressure isoline on the segment’s surface when the microturbine is operating at the rated rotation speed. Method is based on solving Reynolds equations for a thin lubricating layer at the grooves. The developed system of grooves provides static stability of the segment in stationary modes and dynamic in transient modes, vibration suppression, automatic response to changes in load and speed. The calculation method allows finding the optimum thickness of the lubricant layer for a given accuracy of shaft and segment manufacture. It is shown that the load-bearing capacity is maximal when the resultant forces act on a segment, and not between segments. Numerical calculations and experiments have shown that the developed hybrid bearing has a maximum bearing capacity at a given air flow rate for the power range on the shaft from 200 kW to 2000 kW, with a load on the shaft up to 300 kg and a speed of up to 100.000 rpm.

The paper deals with the intelligent network modes based on the Smart Grid concept with the function of two-way energy flow, both from the power system and from its sources of distributed generation. The expanded interpretation and the meaning of the intellectual network concept - Smart Grid - is proposed, based on its abbreviation, which determines the system criteria for its purpose. A new concept is introduced and new definition - Holonic Approach - Smart Grid concept. A new term has been introduced: - "Generating Consumer-Holon" (GC-Holon), which means the ability of an electric consumer to independently generate energy using renewable sources, store it, exchange energy with other similar GC-Holon and the main generating system. In connection with this, the concept of a generating consumer has been introduced. To construct an intelligent network, a holonic structure based on a set of holons (subsystems) is used. The holonic structure assumes subsystems of different nature, located at different levels of aggregation, interconnected in order to form a hierarchy of selfregulating holons, called Holarchy. According to A. Koestler, holons are simultaneously, both whole and partial. They are basically autonomous, which allows them to ensure their existence independently. The two-way energy flow for the holonic structure assumes the possibility of generation and storage of energy due to the internal structure of the electric consumer. The infrastructure of an intelligent network and its applications are considered. A mathematical model of bilateral electric power consumption by a generating consumer is proposed, taking into account tariffs and pricing. This allows you to flexibly regulate energy flow and align the load schedule, minimizing financial expenses for consumed energy.