FORECASTING EMERGENCIES AT HYDRAULIC STRUCTURES

The article deals with the actual problem of emergencies at hydraulic structures. Since time immemorial, man has continuously developed various methods and techniques to take advantage of the benefits of water resources, as well as to protect himself from the ravages of water. Thus, on the territory of the Republic of Tatarstan, a large number of hydraulic structures were erected, which are classified as hydrodynamic hazardous facilities. Accidents at these facilities are sources of man-made emergencies. A number of hydraulic structures on the territory have been in operation without reconstruction for more than 70 years, and most of them are in disrepair. The problem of ensuring the safety of hydraulic structures remains not fully understood and relevant today. As a rule, basically all hydraulic structures are located within or above settlements and are objects of increased risk, since the destruction of dams can lead to an environmental disaster. Also, incomplete destruction of the dam, when the safe operation of the structure is no longer possible, can lead to serious economic losses as a result of the cessation of energy production, hydraulic regulation and water collection in the reservoir. Therefore, careful monitoring is required to identify any possible emergencies. One of the solutions in this situation is the use of various methods for predicting emergencies at hydraulic structures. In this regard, in the work, the authors adapted a mathematical model based on Markov chains, which is distinguished by the efficiency of calculations and a high degree of approximation to statistical data. This model makes it possible to predict the state of hydraulic structures when the data on the water level and the volume of seepage in the hydraulic structure changes. Based on the adapted model, the results of forecasting the water level for real hydraulic structures were obtained.

INCREASING STRUCTURE STIFFNESSOF CORRUGATED ALUMINUM SPOOL

The paper presents the results of a computational and experimental study of aluminumspools with different profile configurations. Mathematical modeling of the product was made using ANSYS 18.2 software package. Models were verified based on actual test results on FP-100/1-10tn testing machine in JSC “Arconic SMZ” Central Factory Lab as per valid normative documents. The study was made on a trial lot of spools with a specially developed type of profile. Comparative analysis was carried out against purchased spools with a profile previously developed by the spool supplier.The spools under study were made of alloy 3104 H19, 0.26 mm strip thickness. The study resulted in work out of empirical formulas helping to determinecollapse loadand calculate the amount of metal forevaluationof stiffness-to-weight ratio. The proposed formulas were added with dimensionlesscoefficients to account for the profile configuration (shape factor) and the relative height of the profile wall.The coefficients were presented in the form of nomograms for easygraphical assessment of the profile performance.The critical height of the profile was determined, at which specific stiffness of the structure is the highest.It was demonstrated that a profile with an inclined vertical wall and a profile with an omega-shaped inner generatrix have lower stiffness than a profile with vertical U-shaped corrugations.The optimal range of the corrugation wall tilt angle was determined to ensure the required level of the structure stiffness, on the one hand, and minimize metal consumption, on the other hand. Comparison of the results of model calculations, the results of computation by the proposed empirical dependencies and actual experimental data showed their high repeatability, whichleads to the conclusion that the proposed formulas are applicable for engineering calculations.The developed profile of a special type makes it possible to reduce the spool metal consumption by 13% while maintaining the required strength performance and the level of stiffness.

UNICELLULAR PLANKTON TRANSFORMATION IN THE RIVER-BAY-RESERVOIR SYSTEM IN THE INITIAL PHASE OF CYANOBACTERIAL BLOOM

The structure and spatial distributionof unicellular plankton of the river Usa, Usinsky Bay and the adjacent section of the Kuibyshev reservoir in the initial period of cyanobacterial bloom is discussed. The greatest development of plankton was recorded in the central part of Usinsky Bay. In the river part, the basis of the total plankton biomass was formed by heterotrophic bacteria and diatoms, and in the bay and reservoir –by cyanobacteria, mainly of the genera Aphanizomenon and Anabaena. Among eukaryotes in Usinskiy Bay, chlorophytesand diatoms prevailed, and in the reservoir - diatoms and ciliates. Another feature of plankton in the bay and reservoir was the increased proportion of heterotrophic bacteria and ciliates associated with cyanobacteria. The analysis of the structural transformation of communities made it possible to distinguish two main clusters of communities, "lotic" and "letic", which differ in their structure and quantitative characteristics.

STRUCTURE AND HIERARCHIES OF INFOCOMMUNICATION SYSTEMS IN DRIVER ASSISTANCE SYSTEMS AS DESIGN TEMPLATES FOR SUBSYSTEMS OF UNMANNED VEHICLE

The article presents the structure of infocommunication systems of unmanned transport systems developed by the author, which combines the main information subsystems of the control loop in Advanced driver-assistance systems (ADAS) and shows their interaction. The analysis of the architecture of the ADAS system as a complex system from the point of view of the application of Mesarovich's theory of hierarchical multilevel systems is given (also known as stratification process) - as a result of which ADAS infocommunication systems are presented in the form of a hierarchy of the strata-layers-echelons type. Such a representation has scientific novelty as the application of stratification methods to the description of ADAS infocommunication systems and practical value in the design of the ADAS architecture and the creation of templates for the design of unmanned transport systems infocommunication subsystems.

IMPROVING THE QUALITY OF CONTROL OF WELDED JOINTS IN THE PRODUCTION OF MECHANICAL ENGINEERING PRODUCTS

The purpose of the work is to develop an automated quality control system for welded joints of cable car structures designed and manufactured at the Skado LLC enterprise (Samara) in order to improve the quality of control. The analysis of requirements for welded structures and welded joints of cable cars is carried out, methods of control of welded joints are considered. A block diagram of an automated system for quality control of welded joints based on the method of ultrasonic testing has been developed. The analysis of ultrasonic sensors on phased arrays is carried out. The sensors and actuators of the system are selected. A scheme for interfacing system elements with a programmable logic controller has been developed. The structure of the system and the scheme of interfacing the system elements with the programmable logic controller are described. A method for performing control has been developed.

ENSURING THE SURVIVABILITY OF SPACECRAFT CONTROL SYSTEM AT CRITICAL FAILURES OF REACTION WHEELS

A method for ensuring the survivability of the spacecraft attitude control system with a minimally redundant cluster of flywheels by General Electric scheme and a magnetic drive in the event of the flywheels' failures is presented. The results of computer simulation were obtained and it was found that in case of failure of any two flywheels, the Earth survey satellite retains the ability to scanning observation given targets.

DETERMINATION OF VIBRATION POWER OF VIBRATION SOURCES OF SPINDLE UNITS OF METAL CUTTING MACHINES

Monitoring the state of spindle assemblies of modern metal-cutting machines using CIP methods implies the possibility of installing control sensors in places with maximum vibration information content. In this regard, the assessment of the informativeness of the vibration field of the spindle assembly, which can be carried out in advance, taking into account the design features, geometric and dimensional characteristics, is an urgent task. Based on the energy approach, using the example of the spindle assembly of a universal lathe, a computational model is proposed, built along the median planes of the walls. On the basis of the calculated model, the equations of the energy balance were compiled taking into account the conditions for the transfer of vibration power between the walls of the housing. The method for determining the vibration power of the main sources in the spindle assemblies is given: a spindle with residual unbalance, a drive gear and bearings. It has been established that the most significant factors determining the vibration power introduced into the spindle unit housing are the operation of the bearings, the weight of the spindle and the location of its center of mass. The result obtained makes it possible to detect incipient defects in the bearings, which, as practice shows, are the defining elements of the parametric reliability of spindle assemblies. The resulting model of the vibration field can be used to determine the reference values of vibration velocities that are formed from sources in the absence of defects.

OPTIMUM MANAGEMENT IN ACHIEVING THE INDUSTRIAL QUALITY GOALS

A mathematical model for targeted control in the field of quality, which is a system of ordinary differential equations with constant coefficients, is considered. The solutions of this system are given for the most common stepwise and linear control laws in practice. An example of optimization based on the classical quadratic functional corresponding to the Taguti quality loss function is considered, using actual data based on the results of an industrial enterprise.

FREE-LIVING CILIATES DURING THE PERIOD OF THE GREATEST CYANOBACTERIAL WATER BLOOM IN THE USINSKY BAY (KUIBYSHEV RESERVOIR)

The study of free-living ciliates in the Usinsky bay (the Kuibyshev reservoir) during the period of mass development of cyanobacteria are presented. The diversity of the ciliate species structure and spatial distribution were studied in summer. The abundance of ciliates varied from 124 to 1176 103ind./m3, biomass – from 6.9 mg/m3 to 104.9 mg/m3 during the study period. No significant differences in the communities of ciliates in different ecotopes of the bay (riverbed, open and overgrown by macrophytes coastal areas) were found. However, on average, in the riverbed part, all indicators of species richness and diversity, and quantitative developmentwere higher than in the littoral zone. The massive development of representatives of s/cl. Peritrichia (up to 51% of abundance and 66% of biomass): single cells species associated with planktonic algae (genera Vorticella, Vaginicola), and colonial free-floating Epistylisprocumbens Zacharias, 1897, was the distinctive feature of ciliate community in the UsinskyBay during the period of greatest cyanobacterial bloom. Water bloom significantly changed the trophic structure of the ciliate community: the role of algophages and nonselective omnivores, ordinary trophic groups of the Reservoir was significantly reduced, and bacterio-detritophages became absolutely dominated. It was shown that the dominant species of cyanobacteria had a significant effect on the ciliate community during the cyanobacterial water bloom.

SCIENTIFIC AND TECHNICAL SOLUTIONS AND METHODS OF COMMUNICATION SERVICES QUALITY CONTROL

The paper is devoted to the analysis of known methods of communication servicesquality control, as well as presented innovative proposals developed by the author.: method of external quality control of services provided by the communication network (Patent for invention of the Russian Federation №2669535), aimed at solving a technical problem, which consists in presenting objective data on the quality of the provided services to consumers of communication services without their interference in the process of network functioning; billing method, taking into account the quality of the provided communication services (Patent for invention of the Russian Federation №2708512), aimed at expanding the functionality of billing systems and allowing to objectively determine the level of quality of the provided communication services for the subscriber; an automated system and method for accepting payments for high-quality communication services (Patent for invention of the Russian Federation №2705422), aimed at increasing the awareness of operators about the quality of communication services, accurate to the element of a composite communication channel.