scholarly journals Mathematical modeling and analysis of dynamic phenomena turnout rail

2017 ◽  
Vol 2017 (10) ◽  
pp. 36-44
Author(s):  
Rafał Kowalik ◽  
Emil Sadowski
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Models ◽  
Railway Track ◽  
Railway Vehicle ◽  
Vehicle Speed ◽  
Modeling And Analysis ◽  
Rail Track ◽  
Pass Through ◽  
Dynamic Phenomena

The article presents the results of simulations carried out for the developments on the railway junction in the instantaneous passage of a railway vehicle. The main focus lies on getting runs all three forces present in the area of the point of contact wheel-rail. Tests carried out for different vehicle speed rail-track. In addition, also presented mathematical models describing the motion of the train to pass through the railway track and discusses the mathematical considerations describing the deflection of the beam under the influence of rolling wheels on it. At the end shows the conclusions of the simulations.

A Finite Element Model of Railway Track and its Application to the Wheel Flat Problem

1994 ◽  
Vol 208 (1) ◽  
pp. 61-72 ◽  
Author(s):  
R G Dong ◽  
S Sankar ◽  
R V Dukkipati
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Element Model ◽  
Railway Track ◽  
Railway Vehicle ◽  
Impact Loads ◽  
Vehicle Speed ◽  
Lift Off ◽  
Wheel Flat ◽  
The Impact

To study the dynamic interactions between the railway vehicle and track, a finite element model of infinitely long track is developed. The track is represented by a Timoshenko beam on discrete pad-tie-ballast supports. The non-linear factors such as loss of wheel-rail contact, rail lift-off from the tie and tie lift-off from the ballast are taken into account. A multi-point wheel-rail contact model is also proposed. The dynamic forces on the track and the strains on the rail are directly calculated from the model. The vehicle could travel on the track forever with an arbitrary time-dependent speed. The steady-state response of a vehicle-track system for a perfect wheel carrying a constant load and travelling at a constant speed over a track with no irregularities is studied using the finite element model and is presented. The impact loads due to wheel flats are also studied with this model. The results show a good correlation with the experimental data available in the literature. Influences of system parameters on the impact loads due to a wheel flat are also investigated. T***he results show that the axle load and vehicle speed are the important factors affecting the wheel-rail impact loads. The impact forces transferred from the rail to the tie are strongly affected by the pad stiffness and tie mass.

scholarly journals A Tool for the Analysis and Characterization of School Mathematical Models

Mathematics ◽  
2021 ◽  
Vol 9 (13) ◽  
pp. 1569
Author(s):  
Jesús Montejo-Gámez ◽  
Elvira Fernández-Ahumada ◽  
Natividad Adamuz-Povedano
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Models ◽  
Educational Research ◽  
Analysis Procedure ◽  
Real System ◽  
The Real ◽  
School Model ◽  
Corresponding Analysis ◽  
Three Components

This paper shows a tool for the analysis of written productions that allows for the characterization of the mathematical models that students develop when solving modeling tasks. For this purpose, different conceptualizations of mathematical models in education are discussed, paying special attention to the evidence that characterizes a school model. The discussion leads to the consideration of three components, which constitute the main categories of the proposed tool: the real system to be modeled, its mathematization and the representations used to express both. These categories and the corresponding analysis procedure are explained and illustrated through two working examples, which expose the value of the tool in establishing the foci of analysis when investigating school models, and thus, suggest modeling skills. The connection of this tool with other approaches to educational research on mathematical modeling is also discussed.

Call for Manuscripts for the 2015 Focus Issue: Mathematical Modeling

2013 ◽  
Vol 18 (9) ◽  
pp. 571
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Models ◽  
Real World ◽  
The Real

This call for manuscripts is requesting articles that address how to use mathematical models to analyze, predict, and resolve issues arising in the real world.

A Stochastic Hierarchical Population System: Excitement, Extinction and Transition to Chaos

2021 ◽  
Vol 31 (14) ◽  
Author(s):  
Irina Bashkirtseva ◽  
Tatyana Perevalova ◽  
Lev Ryashko
Keyword(s):  
Mathematical Modeling ◽  
Food Chain ◽  
Analytical Method ◽  
Three Dimensional ◽  
Biological Parameters ◽  
Top Predator ◽  
Population System ◽  
Modeling And Analysis ◽  
Transition To Chaos ◽  
Random Fluctuations

A problem of the mathematical modeling and analysis of noise-induced transformations of complex oscillatory regimes in hierarchical population systems is considered. As a key example, we use a three-dimensional food chain dynamical model of the interacting prey, predator, and top predator. We perform a comparative study of the impacts of random fluctuations on three key biological parameters of prey growth, predator mortality, and the top predator growth. A detailed investigation of the stochastic excitement, noise-induced transition from order to chaos, and various scenarios of extinction is carried out. Constructive abilities of the semi-analytical method of confidence domains in the analysis of the noise-induced extinction are demonstrated.

On the Planning and Construction of Railway Curved Track

2021 ◽  
Vol 13 (2) ◽  
Author(s):  
Sono Bhardawaj ◽  
Rakesh Chandmal Sharma ◽  
Sunil Kumar Sharma ◽  
Neeraj Sharma
Keyword(s):  
High Speed ◽  
Time Derivative ◽  
Railway Track ◽  
Lateral Acceleration ◽  
Transition Curve ◽  
Railway Vehicle ◽  
Geometric Conditions ◽  
Curve Track ◽  
Curved Track ◽  
Transition Curves

Increasing demand for railway vehicle speed has pushed the railway track designers to develop high-quality track. An important measure of track quality is the character of the transition curve track connecting different intersecting straight tracks. A good transition curve track must be able to negotiate the intermittent stresses and dynamic effects caused by changes in lateral acceleration at high speed. This paper presents the constructional methods for planning transition curves considering the dynamics of movement. These methods consider the non-compensated lateral acceleration, deviation in lateral acceleration and its higher time derivatives. This paper discusses the laying methods of circular, vertical and transition curves. Key aspects in laying a curved track e.g. widening of gauge on curves are discussed in this paper. This paper also suggests a transition curve which is effective not only from a dynamic point of view considering lateral acceleration and its higher time derivative but also consider the geometric conditions along with the required deflection angle.

Mathematical Modeling and Analysis of Covid-19 Infection spreads in India with Restricted Optimal Treatment on Disease Incidence

BIOMATH ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 2106147
Author(s):  
Debkumar Pal ◽  
D Ghosh ◽  
P K Santra ◽  
G S Mahapatra
Keyword(s):  
Mathematical Modeling ◽  
Objective Function ◽  
Reproduction Number ◽  
Disease Incidence ◽  
Treatment Control ◽  
Modeling And Analysis ◽  
Proposed Model ◽  
The Cost ◽  
Disease Free ◽  
The Basic Reproduction Number

This paper presents the current situation and how to minimize its effect in India through a mathematical model of infectious Coronavirus disease (COVID-19). This model consists of six compartments to population classes consisting of susceptible, exposed, home quarantined, government quarantined, infected individuals in treatment, and recovered class. The basic reproduction number is calculated, and the stabilities of the proposed model at the disease-free equilibrium and endemic equilibrium are observed. The next crucial treatment control of the Covid-19 epidemic model is presented in India's situation. An objective function is considered by incorporating the optimal infected individuals and the cost of necessary treatment. Finally, optimal control is achieved that minimizes our anticipated objective function. Numerical observations are presented utilizing MATLAB software to demonstrate the consistency of present-day representation from a realistic standpoint.

Sign in / Sign up

Export Citation Format

Share Document