scholarly journals Step-by-step control of target efficiency indices of the control and measuring equipment stock applied in construction and housing and communal services

2018 ◽  
Vol 170 ◽  
pp. 01010 ◽  
Author(s):  
Rustam Khayrullin ◽  
Pavel Ivanov
Keyword(s):  
Mathematical Model ◽  
Finite Difference ◽  
Measuring Equipment ◽  
Technical Condition ◽  
Measuring Instruments ◽  
Finite Difference Equations ◽  
Target Values ◽  
The Mathematical Model ◽  
Step Control ◽  
Different Levels

The mathematical model is considered for the formation and implementation of development strategies of the stock of control and measuring instruments (CMI) applied in construction and housing and communal services(HCS), and step-by-step control of efficiency target values of the stock. The model is based on a system of finite - difference equations describing the change of number of the CMI samples with different levels of technical perfection and technical condition at each planning interval. The model allows calculating the required number of CMI for procurement and repairs in the various groups for provide target values of efficiency indices at each planning interval. Controller is number of modern CMI samples for procurement and number of modern and obsolete faulty CMI samples for the repairs. The results of calculations are presented.

scholarly journals To preparation of proposals for the target programs of development of housing and communal services

2019 ◽  
Vol 97 ◽  
pp. 02020
Author(s):  
Rustam Khayrullin
Keyword(s):  
Dynamic Systems ◽  
Measuring Equipment ◽  
Stationary Solutions ◽  
Technical Condition ◽  
Ease Of Use ◽  
Stationary Model ◽  
Control Functions ◽  
Constant Coefficients ◽  
The Mathematical Model ◽  
Different Levels

The mathematical model of the formation and implementation of strategies for the development of the park of control and measuring equipment used in construction and housing and communal services is considered. As control functions, purchases, repairs and write-offs are selected. The model is based on a linear system of ordinary differential equations with constant coefficients. The system describes the dynamics of changes in the number of control and measuring equipment samples with different levels of technical excellence and technical condition. The model mainly uses algorithms based on the properties of stationary solutions of dynamic systems. Three different strategies for the development of a measuring equipment park have been considered. For each strategy, analytical and semi-analytical solutions of the stationary model are obtained. A distinctive feature of the model is its visibility and ease of use. The results of calculations are given.

The envelope method in the problem of choosing a rational composition of measuring instruments

2021 ◽  
pp. 68-72
Author(s):  
Il'ya A. Meshchikhin ◽  
Sergej S. Gavryushin
Keyword(s):  
Mathematical Model ◽  
Monitoring Systems ◽  
Measuring Instruments ◽  
Key Points ◽  
Envelope Method ◽  
Loaded State ◽  
The Mathematical Model ◽  
Selection Of ◽  
Rational Composition

As part of the development of monitoring systems for the operation of technical objects, the problem of improving the quality of monitoring systems for the loaded state is considered. Based on the analysis of the mathematical model of the structure and its loading, a methodology for the selection of measuring instruments was developed. The urgency of the problem of calculating substantiation of the choice of key points of the structure is shown, at which it is possible to measure deformations for the subsequent restoration of the existing loads with maximum accuracy. An approach based on the envelope method for determining the rational composition of measuring instruments for restoring the loads acting on the structure is stated.

scholarly journals Diagnostics of supercapacitors

2018 ◽  
Vol 182 ◽  
pp. 01009 ◽  
Author(s):  
Valeriy Martynyuk ◽  
Oleksander Eromenko ◽  
Juliy Boiko ◽  
Tomasz Kałaczyński
Keyword(s):  
Mathematical Model ◽  
Mathematical Models ◽  
Methodological Approach ◽  
Frequency Dispersion ◽  
Technical Condition ◽  
Transient Processes ◽  
Nonlinear Frequency ◽  
Diagnostic Reliability ◽  
General Reliability ◽  
The Mathematical Model

The paper represents the mathematical model for diagnostics of supercapacitors. The research objectives are the problem of determining a supercapacitor technical condition during its operation. The general reliability of diagnostics is described as the methodological and instrumental reliabilities of diagnostics. The instrumental diagnostic reliability of supercapacitor includes the probabilities of errors of the first and second kind, α and β respectively. The methodological approach to increasing the reliability of supercapacitor diagnostic has been proposed, in terms of multi-parameter supercapacitor diagnostic by applying nonlinear, frequency dependent mathematical models of supercapacitors that take into account nonlinearity, frequency dispersion of parameters and the effect of transient processes in supercapacitors. The more frequencies, operating voltages and currents are applied in the supercapacitor diagnostics, the more methodological reliability of diagnostics will increase in relation to the methodological reliability of supercapacitor diagnostics when only one frequency, voltage and current are applied.

scholarly journals ON MATHEMATICAL MODELLING OF METALS DISTRIBUTION IN PEAT LAYERS

2014 ◽  
Vol 19 (4) ◽  
pp. 568-588
Author(s):  
Ilmars Kangro ◽  
Harijs Kalis ◽  
Aigars Gedroics ◽  
Erika Teirumnieka ◽  
Edmunds Teirumnieks
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Finite Difference ◽  
Diffusion Coefficients ◽  
Boundary Value ◽  
Finite Difference Methods ◽  
Circulant Matrix ◽  
Elliptic Type ◽  
Difference Methods ◽  
The Mathematical Model

In this paper we consider averaging and finite difference methods for solving the 3-D boundary-value problem in multilayered domain. We consider the metals Fe and Ca concentration in the layered peat blocks. Using experimental data the mathematical model for calculation of concentration of metals in different points in peat layers is developed. A specific feature of these problems is that it is necessary to solve the 3-D boundary-value problems for elliptic type partial differential equations (PDEs) of second order with piece-wise diffusion coefficients in the layered domain. We develop here a finite-difference method for solving of a problem of one, two and three peat blocks with periodical boundary condition in x direction. This procedure allows to reduce the 3-D problem to a system of 2-D problems by using circulant matrix.

Studi Perpindahan Panas Material pada Sistem Koordinat Segitiga

2017 ◽  
Vol 1 ◽  
pp. 114
Author(s):  
Imam Basuki ◽  
C Cari ◽  
A Suparmi
Keyword(s):  
Heat Transfer ◽  
Mathematical Model ◽  
Heat Conduction ◽  
Partial Differential Equations ◽  
Finite Difference ◽  
Finite Difference Method ◽  
Numerical Solution ◽  
Difference Method ◽  
The Finite Difference Method ◽  
The Mathematical Model

<p class="Normal1"><strong><em>Abstract: </em></strong><em>Partial Differential Equations (PDP) Laplace equation can be applied to the heat conduction. Heat conduction is a process that if two materials or two-part temperature material is contacted with another it will pass heat transfer. Conduction of heat in a triangle shaped object has a mathematical model in Cartesian coordinates. However, to facilitate the calculation, the mathematical model of heat conduction is transformed into the coordinates of the triangle. PDP numerical solution of Laplace solved using the finite difference method. Simulations performed on a triangle with some angle values α and β</em></p><p class="Normal1"><strong><em> </em></strong></p><p class="Normal1"><strong><em>Keywords:</em></strong><em>  heat transfer, triangle coordinates system.</em></p><p class="Normal1"><em> </em></p><p class="Normal1"><strong>Abstrak</strong> Persamaan Diferensial Parsial (PDP) Laplace  dapat diaplikasikan pada persamaan konduksi panas. Konduksi panas adalah suatu proses yang jika dua materi atau dua bagian materi temperaturnya disentuhkan dengan yang lainnya maka akan terjadilah perpindahan panas. Konduksi panas pada benda berbentuk segitiga mempunyai model matematika dalam koordinat cartesius. Namun untuk memudahkan perhitungan, model matematika konduksi panas tersebut ditransformasikan ke dalam koordinat segitiga. Penyelesaian numerik dari PDP Laplace diselesaikan menggunakan metode beda hingga. Simulasi dilakukan pada segitiga dengan beberapa nilai sudut  dan  </p><p class="Normal1"><strong> </strong></p><p class="Normal1"><strong>Kata kunci :</strong> perpindahan panas, sistem koordinat segitiga.</p>

Development of a Mathematical Model to Forecast Solar Radiation and Validating Results Using Machine Learning Technique

2021 ◽  
Author(s):  
H.M.K.K.M.B. Herath ◽  
S.V.A.S.H. Ariyathunge ◽  
G.M.K.B. Karunasena
Keyword(s):  
Neural Network ◽  
Mathematical Model ◽  
Linear Regression ◽  
Solar Radiation ◽  
Multiple Linear Regression ◽  
Rural Areas ◽  
Meteorological Data ◽  
Measuring Instruments ◽  
Linear Regression Method ◽  
The Mathematical Model

Abstract Solar radiation or also referred to as solar power is the general expression for electromagnetic radiation emitted by the Sun. Direct solar radiation is an important factor in global solar radiation and is very influential in the efficiency evaluation of various applications for solar energy. For countries like Sri Lanka, installing a solar radiation instrument in rural areas is a challenge. Thus, both scientific and economically, measuring solar radiation without installing measuring instruments is an advantage. The aim of this study is to development of a mathematical model to predict solar radiation where solar radiation measurement instruments are not installed. The Artificial Neural Network (ANN) was used to verify the predictions of the mathematical model. Multiple Linear Regression (MLR) analysis was used for the development of a mathematical model to predict solar radiation. The model with the highest R2 value (0.5973) was chosen from the 127 equations as the best model that describes the solar radiation that reaches the surface of the earth. The dataset used for this study was meteorological data from the four month HI-SEAS weather station and are composed of ten attributes including date, time, radiation (H), temperature (Tair), pressure (P), humidity (φ), sunrise time, sunset time, wind direction (D), and speed (S). The angle of declination (δ) and sunshine hours (N) were calculated using the dataset. For the training of the neural network, 80 % of the data from the HI-SEAS dataset was used. The remaining data were used for testing both mathematical and ANN models. Results obtained from the multiple linear regression method and the ANN method was compared with the measured values. The experimental results suggested that the mathematical model was predicted the solar radiation with ±100 Wm-2 tolerance for both measured and ANN values.

The Elastic Behaviour of Metal Powder Compacts

2007 ◽  
Vol 534-536 ◽  
pp. 325-328
Author(s):  
Jose Manuel Prado
Keyword(s):  
Mathematical Model ◽  
Simple Model ◽  
Elastic Strain ◽  
Elastic Behaviour ◽  
Compression Tests ◽  
Linear Elastic ◽  
Loading And Unloading ◽  
Powder Compacts ◽  
The Mathematical Model ◽  
Different Levels

In this work the elastic behaviour of metallic powder compacts is studied. Cylindrical specimens with different levels of density have been submitted to uniaxial compression tests with loading and unloading cycles. The analysis of the elastic loadings shows a non linear elasticity which can be mathematically represented by means of a potential law. Results are explained by assuming that the total elastic strain is the contribution of two terms one deriving from the hertzian deformation of the contacts among particles and another that takes into account the linear elastic deformation of the powder skeleton. A simple model based in a one pore unit cell is presented to support the mathematical model.

Simulation of Hydraulic Pipeline Pressure Transients Accompanying Cavitation and Gas Bubbles Using Matlab/Simulink

2006 ◽  
Author(s):  
Jiang Dan ◽  
Songjing Li
Keyword(s):  
Mathematical Model ◽  
Finite Difference ◽  
Finite Difference Method ◽  
Difference Method ◽  
Gas Bubbles ◽  
Simulation Method ◽  
Low Pressure ◽  
Matlab Simulink ◽  
Pressure Transients ◽  
The Mathematical Model

In order to predict pressure transients accompanying cavitation and gas bubbles in hydraulic pipeline operating at low pressure, a mathematical model and a simulation method are studied. The mathematical model is based on the two basic equations of motion and continuity. The growing and collapsing of cavitation and gas bubbles accompanying pressure pulsations are modelled to calculate the volumes of cavitation and gas bubbles. The pipeline dynamic friction model is introduced. Meanwhile, a simulation method, using finite difference method and Matlab/Simulink platform, is developed to handle the prediction of pressure transients. Finally an example of fluid transients inside hydraulic pipeline is simulated after a downstream valve is closed rapidly. Simulation results show that, for a certain example pipeline, the mathematical model can handle the prediction of pressure transients accompanying cavitation and gas bubbles in low pressure pipeline. The use of combining finite difference method with Matlab/Simulink platform provides a relatively simple and effective tool to understand the nature of pressure transients accompanying cavitation and gas bubbles.

scholarly journals Integrated mathematical model of competence-based learning-teaching process

2015 ◽  
Vol 63 (1) ◽  
pp. 245-259 ◽  
Author(s):  
P. Różewski ◽  
O. Zaikin
Keyword(s):  
Mathematical Model ◽  
Queuing Model ◽  
Teaching Process ◽  
Incentive Model ◽  
Ontological Approach ◽  
Qualification Framework ◽  
Open And Distance Learning ◽  
Motivation Model ◽  
The Mathematical Model ◽  
Different Levels

Abstract The competence-based learning-teaching process is a significant approach to the didactical process organization. In this paper the mathematical model of the competence-based learning-teaching process is proposed. The model integrates three models: a knowledge representation model (based on the ontological approach), a motivation model (as a behavioral-incentive model) and a servicing model (in a form of the queuing model). The proposed integrated model allows to control the learning-teaching process on different levels of management. The learning-teaching process can be interpreted as competence-based due to Open and Distance Learning (ODL) philosophy. We assume that the competence is a result of fundamental, procedural and project knowledge acquisition in accordance to the incoming European Qualification Framework.

scholarly journals Diagnostics of Solar Cells

2019 ◽  
Vol 302 ◽  
pp. 01013
Author(s):  
Valeriy Martynyuk ◽  
Juliy Boiko ◽  
Marcin Łukasiewicz ◽  
Ewa Kuliś ◽  
Janusz Musiał
Keyword(s):  
Mathematical Model ◽  
Solar Cells ◽  
Solar Cell ◽  
Series Resistance ◽  
Cell Model ◽  
Methodological Approach ◽  
Technical Condition ◽  
Impedance Model ◽  
Voltage Ratio ◽  
The Mathematical Model

The paper represents the mathematical model for diagnostics of solar cell. The research objectives are the problem of determining a solar cell technical condition during its operation. The solar cell diagnostics is based on the mathematical model of solar cells. The single-diode solar cell model is characterized by a slight deviation of the theoretically calculated characteristics from the characteristics of the real solar cell, one of the reasons being the complexity of the accurate measurement of the series resistance. The single-diode solar cell model uses the current and voltage ratio in the form of an implicit function and it cannot be solved directly. For its solution it is necessary to use numerical methods. This is main disadvantage of the single-diode solar cell model. The methodological approach to increasing the reliability of the solar cell diagnostic has been proposed, in terms of multi-parameter the solar cell diagnostic by applying the solar cell impedance model.

Sign in / Sign up

Export Citation Format

Share Document