scholarly journals Mathematical model of insulation breakdown prediction based on partial discharge characteristics

2021 ◽  
pp. 46-49
Author(s):  
I. V. Komarov ◽  
◽  
D. A. Polyakov ◽  
K. I. Nikitin ◽  
V. Yu. Miroshnik ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Least Squares Method ◽  
Residual Life ◽  
Partial Discharges ◽  
Short Term ◽  
Insulation Failure ◽  
Insulation Thickness ◽  
Solid Dielectrics ◽  
Conducting Research ◽  
Insulation Breakdown

The paper investigates the existing mathematical models of insulation destruction. It has been determined that most of the models for assessing the residual life of insulation are based on models of thermal and thermo-oxidative destruction of insulation materials. Currently, solid dielectrics are gaining popularity, including crosslinked polyethylene, PVC, ethylene-propylene rubber, and others. In such dielectrics, it is possible to estimate the residual life in the short term. This possibility and necessity is due to the possibility of growth of tree defects under the influence of partial discharges. The article describes the proposed mathematical model for assessing the residual resource of insulation by modeling the growth of a defect. To take into account the influence of random variables, the model uses the Weibull distribution. The model assumes the division of the insulation thickness into some areas, each of which is destroyed independently of the others. The destruction of these areas occurs when partial discharges occur with certain energy sufficient to destroy the material. Insulation failure is predicted using the least squares method. The results obtained can be useful in assessing the residual life of insulating materials and in conducting research in this area

EXPERIMENTAL STUDIES OF CAR PROPERTIES ON A PHYSICAL MODEL

2019 ◽  
pp. 10-16
Author(s):  
Oleksii Timkov ◽  
Dmytro Yashchenko ◽  
Volodymyr Bosenko
Keyword(s):  
Mathematical Model ◽  
Remote Control ◽  
Physical Model ◽  
Model Experiment ◽  
Experimental Studies ◽  
Electrical Energy ◽  
Short Term ◽  
Motor Current ◽  
Memory Card ◽  
The Mathematical Model

The article deals with the development of a physical model of a car equipped with measuring, recording and remote control equipment for experimental study of car properties. A detailed description of the design of the physical model and of the electronic modules used is given, links to application libraries and the code of the first part of the program for remote control of the model are given. Atmega microcontroller on the Arduino Uno platform was used to manage the model and register the parameters. When moving the car on the memory card saved such parameters as speed, voltage on the motor, current on the motor, the angle of the steered wheel, acceleration along three coordinate axes are recorded. Use of more powerful microcontrollers will allow to expand the list of the registered parameters of movement of the car. It is possible to measure the forces acting on the elements of the car and other parameters. In the future, it is planned to develop a mathematical model of motion of the car and check its adequacy in conducting experimental studies on maneuverability on the physical model. In addition, it is possible to conduct studies of stability and consumption of electrical energy. The physical model allows to quickly change geometric dimensions and mass parameters. In the study of highway trains, this approach will allow to investigate the various layout schemes of highway trains in the short term. It is possible to make two-axle road trains and saddle towed trains, three-way hitched trains of different layout. The results obtained will allow us to improve not only the mathematical model, but also the experimental physical model, and move on to further study the properties of hybrid road trains with an active trailer link. This approach allows to reduce material and time costs when researching the properties of cars and road trains. Keywords: car, physical model, experiment, road trains, sensor, remote control, maneuverability, stability.

Research on Generator Excitation Parameter Identification - PSS Low-Pass Link Parameter Identification

2013 ◽  
Vol 805-806 ◽  
pp. 716-720
Author(s):  
Tao Xu ◽  
Tian Long Shao ◽  
Dong Fang Zhang
Keyword(s):  
Mathematical Model ◽  
Parameter Identification ◽  
Least Squares Method ◽  
Least Square Method ◽  
Least Square ◽  
National Standards ◽  
Matlab Software ◽  
Low Pass ◽  
Newton Iterations ◽  
The Mathematical Model

Combined with the contents of the study-PSS low-pass link parameter identification. Least-squares method is selected. Using least-square method for PSS low-pass link mathematical model are also deduced. For the results, because of the mathematical model is solving nonlinear equations, cannot used by the Newton method directly. So we choose to use Newton iterations, with this feature, choose to use MATLAB software to solve the equation. Identification of the use of MATLAB software lags after the PSS parameters obtained recognition results compared with national standards, identifying and verifying the practicability.

scholarly journals Automatic Synchronization as the Element of a Power System's Anti-Collapse Complex

2008 ◽  
Vol 45 (6) ◽  
pp. 3-19 ◽  
Author(s):  
J. Barkāns ◽  
D. Žalostība
Keyword(s):  
Mathematical Model ◽  
Power System ◽  
Technical Solution ◽  
Short Term ◽  
Automatic Synchronization ◽  
Area Of Application

Automatic Synchronization as the Element of a Power System's Anti-Collapse Complex In the work, a new universal technical solution is proposed for blackout prevention in a power system, which combines the means for its optimal short-term sectioning and automatic self-restoration to normal conditions. The key element of self-restoration is automatic synchronization. The authors show that for this purpose it is possible to use automatic re-closing with a device for synchronism-check. The results of computations, with simplified formulas and a relevant mathematical model employed, indicate the area of application for this approach. The proposed solution has been created based on many-year experience in the liquidation of emergencies and on the potentialities of equipment, taking into account new features of blackout development that have come into being recently.

scholarly journals THE INNOVATIVE POTENTIAL OF HUMAN RESOURCES AS A FACTOR IN THE DEVELOPMENT OF THE INNOVATIVE TECHNOLOGIES MARKET IN UKRAINE

2021 ◽  
Vol 23 (1(78)) ◽  
pp. 58-74
Author(s):  
I.V. GRYSHCHENKO ◽  
V.F. GRYSHCHENKO
Keyword(s):  
Mathematical Model ◽  
Human Resources ◽  
Market Development ◽  
Short Term ◽  
Model Calculations ◽  
Innovative Technologies ◽  
Innovation Capacity ◽  
Innovative Potential ◽  
The Impact ◽  
The Relationship

Topicality. The successful operation of an economic entity, in the development of the innovative technologies market, is largely determined by the innovative potential of its human resources - by the people who work for it - their knowledge, talents, and skills. The wrong combination of these elements, lack of employees who have the necessary qualifications, lack of harmony in the relationship between employers and employees can inevitably lead to serious financial and economic problems. Improving the efficiency of the use of the innovative potential of human resources in the development of the innovative technologies market is one of the most urgent tasks for any business entity. The competitive advantages of business entities, financial and economic indicators of their activity, ensuring sustainable development of entrepreneurship in general, are depending on the degree and balance of its use. Aim and tasks. The purpose of the work is to analyze and develop on its basis recommendations for increasing the level of the innovative potential of human resources in the context of the development of the innovative technologies market in Ukraine. Research results. The article analyzes the main structural elements of the innovative potential of human resources and identifies the factors influencing its level in Ukraine. The results of the analysis allowed us to build an economic and mathematical model of the relationship between innovation capacity, as an indicator of the development of the innovative technologies market and components of the innovative potential of human resources in Ukraine. This made it possible to predict the level of innovation capacity as an indicator of the innovative technologies market development in Ukraine in the short term. The obtained results allowed us to identify problems and develop recommendations for increasing the level of the innovative potential of human resources in the context of the innovative technologies market development in Ukraine. Conclusion. Based on the developed economic and mathematical model, calculations were made that characterize the relationship between innovation capacity as an indicator of the innovative technologies market development and components of the innovative potential of human resources in Ukraine. As shown in the calculations, the proposed economic and mathematical model with high accuracy allows to assess the impact of components of the innovative potential of human resources on innovation capacity and identify major obstacles for its development, which made it possible to predict trends in innovation capacity as an indicator of the innovative technologies market development in Ukraine in the short term.

scholarly journals The identification of a device based on a Peltier element by the least squares method

2020 ◽  
pp. 17-27
Author(s):  
Vladimir Grinkevich ◽  
Keyword(s):  
Mathematical Model ◽  
Least Squares ◽  
Least Squares Method ◽  
Control Object ◽  
Object Identification ◽  
Model Parameters ◽  
Peltier Element ◽  
Transport Delay ◽  
Non Linear ◽  
The Mathematical Model

The evaluation of the mathematical model parameters of a non-linear object with a transport delay is considered in this paper. A temperature controlled stage based on a Peltier element is an identification object in the paper. Several input signal implementations are applied to the input of the identification object. The least squares method is applied for the calculation of the non-linear differential equitation parameters which describe the identification object. The least squares method is used due to its simplicity and the possibility of identification non-linear objects. The parameters values obtained in the process of identification are provided. The plots of temperature changes in the temperature control system with a controller designed based on the mathematical model of the control object obtained as a result of identification are shown. It is found that the mathematical model obtained in the process of identification may be applied to design controllers for non-linear systems, in particular for a temperature stage based on a Peltier element, and for self-tuning controllers. However, the least square method proposed in the paper cannot estimate the transport delay time. Therefore it is required to evaluate the time delay by temperature transient processes. Dynamic object identification is applied when it is required to obtain a mathematical model structure and evaluate the parameters by an input and output control object signal. Also, identification is applied for auto tuning of controllers. A mathematical model of a control object is required to design the controller which is used to provide the required accuracy and stability of control systems. Peltier elements are applied to design low-power and small- size temperature stage . Hot benches based on a Peltier element can provide the desired temperature above and below ambient temperature.

scholarly journals The Forecasting of Groundwater Fluctuations using Time Series Analysis and Combination of Data-Driven Models

2021 ◽  
Author(s):  
Amirhossein Najafabadipour ◽  
Gholamreza Kamali ◽  
Hossein Nezamabadi-pour
Keyword(s):  
Iron Ore ◽  
Least Squares Method ◽  
Moving Average ◽  
Groundwater Resources ◽  
Mining Area ◽  
Data Driven ◽  
Short Term ◽  
Iron Ore Mine ◽  
Groundwater Fluctuations ◽  
Groundwater Drainage

The Forecasting of Groundwater Fluctuations is a useful tool for managing groundwater resources in the mining area. Water resources management requires identifying potential periods for groundwater drainage to prevent groundwater from entering the mine pit and imposing high costs. In this research, Auto-Regressive Integrated Moving Average (ARIMA) and Holt-Winters Exponential Smoothing (HWES) data-driven models were used for short-term modeling of the groundwater fluctuations in a piezometer around the Gohar Zamin Iron Ore Mine. For this purpose, 250 non-seasonal groundwater fluctuations data in the period 22-Nov-2018 to 29-Jul-2019, 200 data for modeling, and 50 data for prediction were used. To take advantage of all the features of the two developed models, the predictions are combined with different methods and specific weights. The results show better accuracy for the ARIMA method between the two short-term forecasts, while the HWES method requires less time for modeling. Also, among all the predictions made, the highest accuracy for the combined least-squares method is for forecasting the groundwater fluctuations in the short-term. All the forecasts show a decrease in the groundwater fluctuations, indicating pumping wells around the Gohar Zamin Iron Ore Mine area.

scholarly journals Assessment of short/long term electric field strength measurements for a pilot district

Open Physics ◽  
2018 ◽  
Vol 16 (1) ◽  
pp. 69-74
Author(s):  
Cetin Kurnaz ◽  
Dogan Yildiz ◽  
Serap Karagol
Keyword(s):  
Mathematical Model ◽  
Field Strength ◽  
Electric Field ◽  
Electric Field Strength ◽  
Cellular Systems ◽  
Base Stations ◽  
Short Term ◽  
Technological Developments ◽  
Day By Day

Abstract The level of electromagnetic radiation (EMR) exposure increases day by day as natural consequences of technological developments. In recent years, the increasing use of cellular systems has made it necessary to measure and evaluate EMR originating from base stations. In this study, broadband and band selective electric field strength (E) measurements were taken at four different times in order to evaluate the change of short term E in Atakum district of Samsun, Turkey. The measurements were collected from 46 different locations using a SRM 3006 and a PMM 8053 EMR meter in a band from 100 kHz to 3 GHz, and the maximum E (Emax) and the average E (Eavg) were recorded. The highest values have been noticed in these measurements at 9.45 V/m and 17.53 V/m for Eavg and Emax respectively. Apart from these measurements, 24 hour long term E measurements were taken at a location where the highest value was observed and analyzed, to observe the change of Es during a day. At the end of the study, a tentative mathematical model that helps in computing the total E of the medium with 95% accuracy, was obtained.

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