scholarly journals NEURAL NETWORK INTERPOLATION PARAMETERS OF A MULTI-MODE DYNAMIC MODEL OF THE AIRCRAFT ENGINE

2020 ◽  
pp. 98-104
Author(s):  
Aleksandr Tamargazin ◽  
Liudmyla Pryimak

The foundations of the concept of creation of intelligent aircraft engine control systems based on the decomposition of control processes within the architecture of open information systems are considered. Unlike well-known approaches, the suggested approach allows achieving the management goal based on the principle of minimum entropy by redistributing system resources in conditions of their shortage, as well as adapting system characteristics when changing the management situation based on self-learning and self-organization of intelligent control systems. Based on an analysis of the development trends of aircraft engines, as well as development trends of production and technological systems, including the creation of new composite materials and new technologies for the manufacture and control of parts and components of aircraft engines, the intellectualization of their automatic control systems is discussed. Moreover, the development trends of aircraft engine control systems are considered from the development of their structures, functions, properties, and abilities for new qualitative changes. The article gives the general characteristics and the main directions of the design of intelligent control systems for aircraft engines as complex technical objects. The problem of designing nonlinear dynamic models of aircraft engines using artificial neural networks is discussed. The statement of this problem and possible approaches to its solution are being formed. The results of the neural network identification of an aircraft engine are compared using the least-squares method. Such a technique for designing a model of aircraft engines makes it possible to indirectly calculate engine coordinates inaccessible to measurement - traction, fuel consumption, etc. The suggested approach allows calculation of the design of neural networks simulating aircraft engines at each step using standard procedures, which makes it possible to automate the creation of neural networks. To reduce the computation time, it is suggested using the optimization algorithms taking into account changes in the state entropy. This simplifies the implementation of the neural network model of an aircraft engine in real time as part of an onboard computer complex.

2021 ◽  
Vol 2094 (2) ◽  
pp. 022030
Author(s):  
O A Jumaev ◽  
J T Nazarov ◽  
G B Makhmudov ◽  
M T Ismoilov ◽  
M F Shermuradova

Abstract As part of neural network systems, an artificial neural network can perform various functions like diagnostics of technological equipment, control of moving objects and technological processes, forecasting situations, as well as assessing the state and monitoring of technological processes.


1993 ◽  
Vol 115 (2B) ◽  
pp. 392-401 ◽  
Author(s):  
Rahmat Shoureshi

The fundamental concept of feedback to control dynamic systems has played a major role in many areas of engineering. Increases in complexity and more stringent requirements have introduced new challenges for control systems. This paper presents an introduction to and appreciation for intelligent control systems, their application areas, and justifies their need. Specific problem related to automated human comfort control is discussed. Some analytical derivations related to neural networks and fuzzy optimal control as elements of proposed intelligent control systems, along with experimental results, are presented. A brief glossary of common terminology used in this area is included.


2020 ◽  
Vol 2020 (10) ◽  
pp. 54-62
Author(s):  
Oleksii VASYLIEV ◽  

The problem of applying neural networks to calculate ratings used in banking in the decision-making process on granting or not granting loans to borrowers is considered. The task is to determine the rating function of the borrower based on a set of statistical data on the effectiveness of loans provided by the bank. When constructing a regression model to calculate the rating function, it is necessary to know its general form. If so, the task is to calculate the parameters that are included in the expression for the rating function. In contrast to this approach, in the case of using neural networks, there is no need to specify the general form for the rating function. Instead, certain neural network architecture is chosen and parameters are calculated for it on the basis of statistical data. Importantly, the same neural network architecture can be used to process different sets of statistical data. The disadvantages of using neural networks include the need to calculate a large number of parameters. There is also no universal algorithm that would determine the optimal neural network architecture. As an example of the use of neural networks to determine the borrower's rating, a model system is considered, in which the borrower's rating is determined by a known non-analytical rating function. A neural network with two inner layers, which contain, respectively, three and two neurons and have a sigmoid activation function, is used for modeling. It is shown that the use of the neural network allows restoring the borrower's rating function with quite acceptable accuracy.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Idris Kharroubi ◽  
Thomas Lim ◽  
Xavier Warin

AbstractWe study the approximation of backward stochastic differential equations (BSDEs for short) with a constraint on the gains process. We first discretize the constraint by applying a so-called facelift operator at times of a grid. We show that this discretely constrained BSDE converges to the continuously constrained one as the mesh grid converges to zero. We then focus on the approximation of the discretely constrained BSDE. For that we adopt a machine learning approach. We show that the facelift can be approximated by an optimization problem over a class of neural networks under constraints on the neural network and its derivative. We then derive an algorithm converging to the discretely constrained BSDE as the number of neurons goes to infinity. We end by numerical experiments.


Author(s):  
Saša Vasiljević ◽  
Jasna Glišović ◽  
Nadica Stojanović ◽  
Ivan Grujić

According to the World Health Organization, air pollution with PM10 and PM2.5 (PM-particulate matter) is a significant problem that can have serious consequences for human health. Vehicles, as one of the main sources of PM10 and PM2.5 emissions, pollute the air and the environment both by creating particles by burning fuel in the engine, and by wearing of various elements in some vehicle systems. In this paper, the authors conducted the prediction of the formation of PM10 and PM2.5 particles generated by the wear of the braking system using a neural network (Artificial Neural Networks (ANN)). In this case, the neural network model was created based on the generated particles that were measured experimentally, while the validity of the created neural network was checked by means of a comparative analysis of the experimentally measured amount of particles and the prediction results. The experimental results were obtained by testing on an inertial braking dynamometer, where braking was performed in several modes, that is under different braking parameters (simulated vehicle speed, brake system pressure, temperature, braking time, braking torque). During braking, the concentration of PM10 and PM2.5 particles was measured simultaneously. The total of 196 measurements were performed and these data were used for training, validation, and verification of the neural network. When it comes to simulation, a comparison of two types of neural networks was performed with one output and with two outputs. For each type, network training was conducted using three different algorithms of backpropagation methods. For each neural network, a comparison of the obtained experimental and simulation results was performed. More accurate prediction results were obtained by the single-output neural network for both particulate sizes, while the smallest error was found in the case of a trained neural network using the Levenberg-Marquardt backward propagation algorithm. The aim of creating such a prediction model is to prove that by using neural networks it is possible to predict the emission of particles generated by brake wear, which can be further used for modern traffic systems such as traffic control. In addition, this wear algorithm could be applied on other vehicle systems, such as a clutch or tires.


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