Informational aspects at model of power consumption by main drainage facilities of iron-ore mining enterprises

The work investigates into variable informational approaches to modeling power consumption by main drainage facilities of ore mining enterprises with underground mining method. Methodological recommendations for using the models are also designed. The research deals with general methodological approaches to model formation with both power consumption indices for drainage facilities and corresponding costs. Logistics of model formation is substantiated, namely, combination of classic multifactor regression modeling with modern digital modeling methods – automated control systems used for drainage facilities. Principles of building fuzzy logic controllers and algorithms of their functioning under multichannel control are determined in detail. The improved fuzzy logic-based variant is proposed and combined, with correlation analysis, to provide the basis for developing algorithms of the automated control systems of electric power consumption. There is an example of developing a “road map” for implementing a generalized algorithm for automated control systems power flows for two current cases – a selective tariff with limited daily contract-based power consumption and that with a variable tariff. It is established that application of the two-rate hourly tariff with its conditional distribution (Night/Peak) instead of the three-rate tariff (Night/Half-Peak/Peak) on a single-use basis leads to a thirteen percent increase of daily power costs with a single-channel control of the ore flow and a seven percent increase with two-channel control (ore flow and drainage simultaneously). The use of fuzzy logic controllers enables minimizing these losses.

Improving the Accuracy of the Output Voltage of the Converter by Changing the Load Parameters

In the article on the basis of the theory of invariance the increase of accuracy of work of system with the converter for nuclear magnetic logging under condition of change of parameters of loading is considered. Based on the proposed functional scheme of two-channel control, formulas are given to determine the structural relationships and internal influences on the parameters of the control system components to reduce the impact of disturbances that occur both by changing load parameters and by changing the supply voltage. To maintain the required value of the carrier voltage amplitude, it is necessary to increase the reference voltage or decrease the amplitude of the sawtooth voltage, which is equivalent to increasing the gain of the feedback circuit. In this case, if you increase the gain of the feedback circuit, you must ensure that the stability of the system is maintained. The implementation of these proposals gives a more accurate formation of the bypass probing signal. The given functional scheme provides realization of regulation and stabilization of amplitude. The paper considers various options for reducing the effect of power supply perturbation on the output parameters of the converter. By changing the period of operation of the sawtooth voltage generator, which is determined by the frequency of the voltage-controlled generator and depends on the output frequency of the inverter, which varies depending on the parameters and properties of the rock during logging, the accuracy of stabilizing the amplitude of the probe signal increases. In the proposed two-channel control system, the first channel provides regulation and stabilization of the amplitude of the output voltage in accordance with the reference voltage. The second channel provides a change in the frequency of the sawtooth voltage generator by determining the period of the voltage-controlled generator from the phase detector, which determines the deviation of the real frequency from the frequency of the reference generator. The application of the above techniques allows to build circuit implementations of the system with transducers for nuclear magnetic logging, which meet the requirements for the accuracy of the formation of the bypass probing signal.

Hitting Times of Some Critical Events in RNA Origins of Life

Can a replicase be found in the vast sequence space by random drift? We partially answer this question through a proof-of-concept study of the times of occurrence (hitting times) of some critical events in the origins of life for low-dimensional RNA sequences using a mathematical model and stochastic simulation studies from Python software. We parameterize fitness and similarity landscapes for polymerases and study a replicating population of sequences (randomly) participating in template-directed polymerization. Under the ansatz of localization where sequence proximity correlates with spatial proximity of sequences, we find that, for a replicating population of sequences, the hitting and establishment of a high-fidelity replicator depends critically on the polymerase fitness and sequence (spatial) similarity landscapes and on sequence dimension. Probability of hitting is dominated by landscape curvature, whereas hitting time is dominated by sequence dimension. Surface chemistries, compartmentalization, and decay increase hitting times. Compartmentalization by vesicles reveals a trade-off between vesicle formation rate and replicative mass, suggesting that compartmentalization is necessary to ensure sufficient concentration of precursors. Metabolism is thought to be necessary to replication by supplying precursors of nucleobase synthesis. We suggest that the dynamics of the search for a high-fidelity replicase evolved mostly during the final period and, upon hitting, would have been followed by genomic adaptation of genes and to compartmentalization and metabolism, effecting degree-of-freedom gains of replication channel control over domain and state to ensure the fidelity and safe operations of the primordial genetic communication system of life.

Polynomial matrix synthesis method of a subordinate control system

The main difference between controlsyn thesis approaches is the various mathematical representation of a plant or system model. The aim of the work is to represent a single channel control plant model by a multichannel one and to obtain an identical design result for a single channel multiloop synthesis method by a multichannel one. For these purposes, direct current motor model is used as an example of a single channel plant. Classical approach to design control system for that kind of plant is to describe it as a serial connected transfer functions and design a multiloop system in accordance with subordinate concept. Polynomial matrix synthesis method with Sylvester matrix is utilized to make identical subordinate regulator. By several transformations, polynomial matrix description was obtained, that describe the plant as one input and three output model and subordinate regulator as a three input and one output model. Arbitrary parameters of regulator were introduced for extended null placement.

Nonlinear tuning of PT symmetry and non-Hermitian topological states

Topology, parity-time (PT) symmetry, and nonlinearity are at the origin of many fundamental phenomena in complex systems across the natural sciences, but their mutual interplay remains unexplored. We established a nonlinear non-Hermitian topological platform for active tuning of PT symmetry and topological states. We found that the loss in a topological defect potential in a non-Hermitian photonic lattice can be tuned solely by nonlinearity, enabling the transition between PT-symmetric and non–PT-symmetric regimes and the maneuvering of topological zero modes. The interaction between two apparently antagonistic effects is revealed: the sensitivity close to exceptional points and the robustness of non-Hermitian topological states. Our scheme using single-channel control of global PT symmetry and topology via local nonlinearity may provide opportunities for unconventional light manipulation and device applications.

The System of Automatic Control of Fuel Supply to the Boiler at the Thermal Power Plant

The article is devoted to the analysis of the technological process of heat load control and cost-effective fuel combustion in furnaces of drum steam generators at a thermal power plant. The object of automation – boiler unit type “Е-75-3,9-440G” – is analyzed. The mathematical model of fuel and air supply system to the steam generator is developed according to installed equipment characteristics. The model’s parameters are calculated. The actuating element of the system is an electric single-turn mechanism designed to actuate shut-off and control valves in the fuel and air supply channels. Two-channel control system is synthetized for providing an optimal ratio of fuel and air consumption with oxygen content correction in the flue gases. The automatic control system model is realized in Matlab application package, Simulink programming environment. The achieved results show the right settings for cascade control system. In conclusion, an example of the necessary technical equipment complex is listed for technical implementation of the developed control system.