Geoecological justification of a project of sustainable shipping on a Volga channel section in the Nizhny Novgorod region

Background. The Volga river channel with rapids limiting the navigation parameters of large-tonnage vessels between the cities of Gorodets and Nizhniy Novgorod is considered in the structure of the Unified deep-water system of waterways of the European part of the Russian Federation.Aim. To justify the need to develop design solutions providing sustainable navigation in the limiting river section under study during the entire navigation period.Materials and methods. An analysis of engineering-geological and geoecological conditions of the region, including a limiting channel section of the Volga.Results. The engineering-geological and geoecological conditions of the region were characterized. A brief description of individual project proposals, including two priority construction projects, a low-pressure hydroelectric unit and a ship canal, was provided with a comparative assessment of natural and man-made factors arising during their implementation.Conclusion. The implementation of the project for the construction of the Volgo-Don 2 canal should be an important stage in the development of the Unified deep-water system of waterways in the European part of the Russian Federation. It will replenish the Don River from the Volga in order to improve navigation conditions, land irrigation, water supply to settlements, and power generation.

MODELS OF SYSTEMS OF QUASIPERIODIC PROCESSES BASED ON CYLINDRICAL AND CIRCULAR IMAGES

The behavior of objects in many practical situations has a quasiperiodic character - the presence of noticeable periodicity with random variations of quasiperiods. For example, noise and vibration of an aircraft engine, hydroelectric unit, seasonal and daily fluctuations in atmospheric temperature, etc. In this case, the object can have several parameters, therefore the object is described by a system of several time series, that is, several random processes. The emerging monitoring tasks (assessing the state of an object and its forecast) require setting a model of such a system of processes and identifying it for a particular object based on the results of its observations. In this paper, to represent a quasi-periodic process, an autoregressive model is used in the form of sweeps of several cylindrical or circular images along a spiral. Choosing the values of a small number of parameters of this model, one can describe and simulate a wide class of systems of quasiperiodic processes. The problem of identifying a model is considered, that is, determining the values of its parameters at which it, in a certain sense, best corresponds to the actually observed process. This problem is solved using a pseudo-gradient adaptive procedure, the advantage of which is its real-time operation with low computational costs.

Project and financial analysis of investment potential of hydraulic test stand for repair companies and service centers

Currently, stationary domestic and foreign test stands are used for assessing the technical condition of bulk hydraulic drives in the repair enterprises and service centers. However, the used domestic stands have disadvantages associated with low accuracy and reliability of the results obtained, limited ranges of diagnostic parameters, and the inability to implement the methods of manufacturers. (Research purpose) The research purpose is in evaluating the investment attractiveness of the hydrostand for repair companies and service centers of hydroelectric unit manufacturers and make a conclusion about its competitiveness. (Materials and methods) Authors have developed a hydrostand for monitoring and evaluating the technical condition, adjustment and post-repair running-in of hydraulic units of a volumetric hydraulic drive. The article presents the estimated cost of its production. The article presents the methodology for calculation of economic efficiency of developed and implemented hydroscand. (Results and discussion) The article shows the feasibility of development by conducting a design and financial analysis of investment attractiveness in relation to the currently operating small innovative enterprise LLC "Agroservice", Saransk. The project was the implementation of designed hydroscand at site for repair of volumetric hydraulic actuators. The cost of manufacturing a new hydrostand was determined in the course of research and is of 1557910 rubles, which is 10.4 percent of the cost of foreign and 44.5 percent of the cost of domestic analogues with higher technical capabilities. (Conclusions) The analysis showed that hydrostand has a relatively low payback period, a high value of the return index and internal rate of return, and a lower cost. These indicators increase its competitiveness and attractiveness among potential consumers.

A hybrid approach for measuring the vibrational trend of hydroelectric unit with enhanced multi-scale chaotic series analysis and optimized least squares support vector machine

Accurate vibrational trend measuring for hydroelectric unit (HEU) is of great significance for safe and economic operation of unit. For this purpose, a novel hybrid approach based on variational mode decomposition (VMD), singular value decomposition (SVD)-based phase space reconstruction (PSR) and least squares support vector machine (LSSVM) improved with adaptive sine cosine algorithm optimization (ASCA) is proposed. Firstly, the raw vibration signal is preprocessed into several components with different scales by VMD, while the residual of VMD is defined as an additional component. Then, SVD with median filtering is utilized to unearth the dominating characteristic ingredients of each component, with which the chaotic series analysis will be effectively implemented. Moreover, the optimal parameters of PSR for each original component are determined by applying grid search on the corresponding dominating component. Later, LSSVM improved by ASCA are established for all the components, whose inputs and outputs are obtained by performing PSR with the optimal parameters. Finally, the measuring results of vibration trend are deduced by accumulating the prediction values of all the components. Furthermore, five related methods are employed to evaluate the effectiveness of the proposed approach. The results illustrate that: (1) the VMD-based models obtained better evaluation indexes compared with the relevant models through significantly weakening the non-stationarity of the original signal; (2) the proposed SVD-based PSR enhanced efficiency of chaotic system restoration, thus to improve the measuring accuracy effectively; (3) the proposed ASCA optimization algorithm could effectively search the parameters of LSSCVM, which contributes to improving model performance.