scholarly journals Time Coordination of Periodic Passenger Train Connections in Conditions of Single-Track Lines

2021 ◽  
Vol 2021 ◽  
pp. 1-17
Author(s):  
Filip Lorenz ◽  
Vit Janos ◽  
Dusan Teichmann ◽  
Michal Dorda
Keyword(s):  
Mathematical Model ◽  
Mathematical Programming ◽  
Real Data ◽  
Real Problem ◽  
Single Track ◽  
Railway Stations ◽  
Optimization Software ◽  
Proposed Model ◽  
The Individual ◽  
The Given

The article addresses creation of a mathematical model for a real problem regarding time coordination of periodic train connections operated on single-track lines. The individual train connections are dispatched with a predefined tact, and their arrivals at and departures to predefined railway stations (transfer nodes) need to be coordinated one another. In addition, because the train connections are operated on single-track lines, trains that pass each other in a predefined railway stations must be also coordinated. To optimize the process, mathematical programming methods are used. The presented article includes a mathematical model of the given task, and the proposed model is tested with real data. The calculation experiments were implemented using optimization software Xpress-IVE.

THE DEVELOPMENT OF THE MATHEMATICAL MODEL OF PREDICTING THE INDICATORS OF ACCREDITATION OF TECHNICAL UNIVERSITIES IN THE RUSSIAN FEDERATION

2017 ◽  
pp. 27-38
Author(s):  
Olga Mikhaylovna Tikhonova ◽  
Alexander Fedorovich Rezchikov ◽  
Vladimir Andreevich Ivashchenko ◽  
Vadim Alekseevich Kushnikov
Keyword(s):  
Mathematical Model ◽  
System Dynamics ◽  
Regression Model ◽  
Oriented Graph ◽  
Real Data ◽  
Educational Process ◽  
Proposed Model ◽  
Linear Differential ◽  
The University ◽  
The Mathematical Model

The paper presents the system of predicting the indicators of accreditation of technical universities based on J. Forrester mechanism of system dynamics. According to analysis of cause-and-effect relationships between selected variables of the system (indicators of accreditation of the university) there was built the oriented graph. The complex of mathematical models developed to control the quality of training engineers in Russian higher educational institutions is based on this graph. The article presents an algorithm for constructing a model using one of the simulated variables as an example. The model is a system of non-linear differential equations, the modelling characteristics of the educational process being determined according to the solution of this system. The proposed algorithm for calculating these indicators is based on the system dynamics model and the regression model. The mathematical model is constructed on the basis of the model of system dynamics, which is further tested for compliance with real data using the regression model. The regression model is built on the available statistical data accumulated during the period of the university's work. The proposed approach is aimed at solving complex problems of managing the educational process in universities. The structure of the proposed model repeats the structure of cause-effect relationships in the system, and also provides the person responsible for managing quality control with the ability to quickly and adequately assess the performance of the system.

scholarly journals Modeling of aircraft jet noise in airports

2018 ◽  
Vol 234 ◽  
pp. 01003
Author(s):  
Hristina Georgieva ◽  
Krasin Georgiev
Keyword(s):  
Mathematical Model ◽  
Empirical Model ◽  
Jet Noise ◽  
Real Data ◽  
Aircraft Noise ◽  
Degree Of Freedom ◽  
The Real ◽  
Proposed Model ◽  
Passenger Aircraft ◽  
Semi Empirical

A mathematical model with 4 degree of freedom created in Matlab for aircraft final landing trajectory is described in this paper. A midsize commercial passenger aircraft similar to an Airbus A320 has been chosen as a reference aircraft. The parameters of model are obtained from Airbus, Eurocontrol and the approach procedure at the Munich airport is selected up from Jeppesen Airway manual. A semi-empirical model of Stone for predicting the jet noise has been used. The proposed model was validated against 10 real flights obtained from Aircraft noise monitoring at Munich airport. The computed error between the real data and modelling is reported on. Obtained results are presented numerical and graphically. The observed effects of aircraft speed, aircraft angle of descent and aircraft weight for reduction of aircraft jet noise in airports represent subjects of discussions in the paper.

scholarly journals Mathematical Model with Social Distancing Parameter for Early Estimation of COVID-19 Spread

2020 ◽  
Author(s):  
Saroj Kumar Chandra ◽  
Avaneesh Singh ◽  
Manish Kumar Bajpai
Keyword(s):  
Mathematical Model ◽  
Antiviral Treatment ◽  
Preventive Measure ◽  
Real Data ◽  
Data Set ◽  
Social Distancing ◽  
Proposed Model ◽  
The World ◽  
Spread Estimation ◽  
Day By Day

AbstractCOVID-19 is well known to everyone in the world. It has spread around the world. No vaccine or antiviral treatment is available till now. COVID-19 patients are increasing day by day. All countries have adopted social distancing as a preventive measure to reduce spread. It becomes necessary to estimate the number of peoples going to be affected with COVID-19 in advance so that necessary arrangements can be done. Mathematical models are used to provide early disease estimation based on limited parameters. In the present manuscript, a novel mathematical model with a social distancing parameter has been proposed to provide early COVID-19 spread estimation. The model has been validated with real data set. It has been observed that the proposed model is more accurate in spread estimation.

scholarly journals Research of the cooperation technology between the air traffic control service and the aerodrome service

2021 ◽  
Vol 24 (4) ◽  
pp. 8-19
Author(s):  
K. A. Batalov ◽  
M. V. Kulakov ◽  
I. A. Chekhov
Keyword(s):  
Mathematical Model ◽  
Traffic Control ◽  
Air Traffic Control ◽  
Entire Range ◽  
Study Circles ◽  
Sequence Of Events ◽  
Proposed Model ◽  
The Mathematical Model ◽  
The Given ◽  
Control Service

The article considers the process of cooperation between the ATC and airport operation services. The analysis considers the procedures of cooperation while inspecting a runway before performing flights, aircraft departure and arrival that encompass the entire range of coordinated operations. For each procedure, the costs of aircraft delays are calculated. The assessment was carried out by synthesizing the chronology of services cooperation in real conditions. On the basis of the collected data flowcharts of services cooperation to ensure flights of an airport and the ATM services were built. To provide a visual comparison of the existing and proposed model sof services cooperation the networks of services cooperation were built based on the mathematical model of the graphic chart. The operation network establishes the sequence of events to provide departure of one aircraft operating a scheduled flight of an airline. Within the given study the ATC service and the aerodrome service are involved to ensure a departure. Cooperation between the operation and dispatch service of the airport and an aircraft crew is conditional because in this case they do not impact the technology of cooperation. The network is a particular set of dots(summits)interconnected by lines (links). In the case of our study, circles are events (performed work). Directional segments (lines) are work connecting events to each other. While assessing the process of cooperation during arrival and departure, two cases were considered: the runway is occupied or clear.The runway could be occupied for different reasons: available vehicles, people, animals or flocks of birds on the runway. The study of the cooperation technology was carried out for 12 monthsof making scheduled flights at Zhukovsky and Ostafievo airports on the basis of every day flight plans.

A Epidemic Model with Inhomogeneity and Mobility Based on Cellular Automata

2013 ◽  
Vol 709 ◽  
pp. 871-874 ◽  
Author(s):  
Jia Tai Gang ◽  
Peng Yan Shi ◽  
San Shan Gang
Keyword(s):  
Cellular Automata ◽  
Influenza A ◽  
Infected Individual ◽  
Real Data ◽  
Population Movement ◽  
Cellular Automata Model ◽  
Proposed Model ◽  
Influenza A H1n1 ◽  
Movement Parameters ◽  
The Individual

A cellular automata model with inhomogeneity and mobility was presented. The inhomogeneity in individuals’ behaviors was considered by assigning the distance on their neighbors, varying levels of infectivity and susceptibility. The individual mobility was reflected by random walk cellular automata. The proposed model can serve as a basis to simulate influenza A (H1N1) based on real data. We studied the effect of two population movement parameters on the epidemic propagation: the percentage and the max-distance of population movement. The results show that the epidemic spreading is more sensitive to the former. The infected individuals are positive growth while the percentage of population movement increases. And the number of infected individual eventually stabilizes in the case of plotting the relation of the max-distance against the infected.

scholarly journals Postboxes Quantitative Optimization Model

2020 ◽  
Vol 12 (5) ◽  
pp. 1945
Author(s):  
Milica Šelmić ◽  
Miloš Nikolić ◽  
Aleksandar Čupić
Keyword(s):  
Mathematical Model ◽  
Decision Support ◽  
Support System ◽  
Transportation Networks ◽  
Real Data ◽  
Traditional Model ◽  
Access Points ◽  
Proposed Model ◽  
Postal Network ◽  
Technological Developments

Technological developments are having a significant impact on purchasing habits and consumer behavior, and threaten the traditional model of the delivery of goods by post. The replacement of traditional letter-post items with electronic forms of communication has led to declines in the volume of postal items. Therefore, the collection of postal items has become very inefficient. This paper proposes that the postal network segment needs to be reorganized by reducing the current number of installed postboxes. To this end, a mathematical model has been defined. Considering that postboxes are one of the most basic access points to the postal network, territorial accessibility must be taken into account. The proposed model, with minor modifications, can easily be applied to optimize other access points in transportation networks. For testing purposes, this paper presents the results of computational experiments based on real data. The final result consists of scenarios that present a decision support system for the redesign of postal networks.

Trust as a Skill

2018 ◽  
Vol 30 (1) ◽  
pp. 44-80
Author(s):  
Larysa Tamilina ◽  
Natalya Tamilina
Keyword(s):  
Skill Acquisition ◽  
Social Trust ◽  
Analytical Framework ◽  
Optimal Level ◽  
Trust Formation ◽  
Proposed Model ◽  
The Individual ◽  
System Frequency ◽  
The Given

A growing body of research is considering how social trust is built at the individual and societal levels. This study introduces a new conceptual framework of trust formation by uniting dispositional and experiential determinants into a single analytical framework. By drawing on psychological theories of skill acquisition, we describe trust as shaped by four factors: crystallised, cognitive, contact and context. We combine these four factors into a 4C-component analytical model by establishing links between them and explaining the rationale behind their individual and joint effects on trust. The proposed model is tested with the Programme for the International Assessment of Adult Competencies (PIAAC) public-use data. Both theoretical and empirical elaborations suggest that context is the strongest driver of trust formation. Good contexts also spur more trust when individuals already possess crystallised knowledge and can display faith in others. Such knowledge can be learned if it is missing, but how efficiently depends on the quality of one’s cognitive system, frequency of contacts with others and the distance between one’s actual knowledge of trust and the optimal level of trust knowledge for the given context.

scholarly journals Common Mathematical Model of Fatigue Characteristics

10.14311/570 ◽  
2004 ◽  
Vol 44 (3) ◽  
Author(s):  
Z. Maléř ◽  
S. Slavík ◽  
T. Marczi ◽  
M. Růžička
Keyword(s):  
Mathematical Model ◽  
Stress Ratio ◽  
Good Description ◽  
Test Time ◽  
Model Following ◽  
Proposed Model ◽  
Fatigue Data ◽  
Mutual Comparison ◽  
Fatigue Characteristics ◽  
The Individual

This paper presents a new common mathematical model which is able to describe fatigue characteristics in the whole necessary range by one equation only:log N = A(R) + B(R) ∙ log Sawhere A(R) = AR2 + BR + C and B(R) = DR2 + AR + F.This model was verified by five sets of fatigue data taken from the literature and by our own three additional original fatigue sets. The fatigue data usually described the region of N 104 to 3 x 106 and stress ratio of R = -2 to 0.5. In all these cases the proposed model described fatigue results with small scatter. Studying this model, following knowledge was obtained:– the parameter ”stress ratio R” was a good physical characteristic– the proposed model provided a good description of the eight collections of fatigue test results by one equation only– the scatter of the results through the whole scope is only a little greater than that round the individual S/N curve– using this model while testing may reduce the number of test samples and shorten the test time– as the proposed model represents a common form of the S/N curve, it may be used for processing uniform objective fatigue life results, which may enable mutual comparison of fatigue characteristics.

EXPONENTIATED HALF-LOGISTIC LOMAX DISTRIBUTION WITH PROPERTIES AND APPLICATION

2019 ◽  
Vol XVI (2) ◽  
pp. 1-11
Author(s):  
Farrukh Jamal ◽  
Hesham Mohammed Reyad ◽  
Soha Othman Ahmed ◽  
Muhammad Akbar Ali Shah ◽  
Emrah Altun
Keyword(s):  
Real Data ◽  
Continuous Model ◽  
Model Parameters ◽  
Data Set ◽  
Lomax Distribution ◽  
Mathematical Properties ◽  
Proposed Model ◽  
Probability Weighted Moment ◽  
Record Statistics ◽  
Maximum Likelihood Criterion

A new three-parameter continuous model called the exponentiated half-logistic Lomax distribution is introduced in this paper. Basic mathematical properties for the proposed model were investigated which include raw and incomplete moments, skewness, kurtosis, generating functions, Rényi entropy, Lorenz, Bonferroni and Zenga curves, probability weighted moment, stress strength model, order statistics, and record statistics. The model parameters were estimated by using the maximum likelihood criterion and the behaviours of these estimates were examined by conducting a simulation study. The applicability of the new model is illustrated by applying it on a real data set.

Application of the turbidity ratio method in the spherical particle size determination in the range m ∈ and α ∈

1979 ◽  
Vol 44 (7) ◽  
pp. 2064-2078 ◽  
Author(s):  
Blahoslav Sedláček ◽  
Břetislav Verner ◽  
Miroslav Bárta ◽  
Karel Zimmermann
Keyword(s):  
Refractive Index ◽  
Spherical Particle ◽  
Ratio Method ◽  
Refractive Indices ◽  
Relative Refractive Index ◽  
Particle Size Determination ◽  
The Individual ◽  
The Given ◽  
Turbidity Ratio ◽  
Selection Of

Basic scattering functions were used in a novel calculation of the turbidity ratios for particles having the relative refractive index m = 1.001, 1.005 (0.005) 1.315 and the size α = 0.05 (0.05) 6.00 (0.10) 15.00 (0.50) 70.00 (1.00) 100, where α = πL/λ, L is the diameter of the spherical particle, λ = Λ/μ1 is the wavelength of light in a medium with the refractive index μ1 and Λ is the wavelength of light in vacuo. The data are tabulated for the wavelength λ = 546.1/μw = 409.357 nm, where μw is the refractive index of water. A procedure has been suggested how to extend the applicability of Tables to various refractive indices of the medium and to various turbidity ratios τa/τb obtained with the individual pairs of wavelengths λa and λb. The selection of these pairs is bound to the sequence condition λa = λ0χa and λb = λ0χb, in which b-a = δ = 1, 2, 3; a = -2, -1, 0, 1, 2, ..., b = a + δ = -1, 0, 1, 2, ...; λ0 = λa=0 = 326.675 nm; χ = 546.1 : 435.8 = 1.2531 is the quotient of the given sequence.

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