scholarly journals Key Aspects of the Proper Formulation of the Model in Numerical Analysis of the Influence of Mining Exploitation on Buildings

2015 ◽  
Vol 36 (2) ◽  
pp. 17-28
Author(s):  
Lucyna Florkowska ◽  
Jan Walaszczyk
Keyword(s):  
Numerical Simulation ◽  
Mathematical Model ◽  
Numerical Modelling ◽  
Underground Mining ◽  
Structural Characteristics ◽  
Number Of Factors ◽  
Proper Formulation ◽  
Key Aspects ◽  
The Impact ◽  
Complex Matter

Abstract Numerical modelling is an important tool used to analyse various aspects of the impact of underground mining on existing and planned buildings. The interaction between the building and the soil is a complex matter and in many cases a numerical simulation is the only way of making calculations which will take into consideration the co–existence of a number of factors which have a significant influence on the solution. The complexity of the matter also makes it a difficult task to elaborate a proper mathematical model – it requires both a thorough knowledge of geologic conditions of the subsoil and the structural characteristics of the building. This paper discusses the most important problems related to the construction of a mathematical model of a building-mining subsoil system. These problems have been collected on the basis of many years of experience the authors have in observing the surveying and tensometric deformations of the rock–mass and buildings as well as in mathematical and numerical modelling of the observed processes.

Simulation the sedimentation of a finely dispersed medium under the impact of pressure waves

2012 ◽  
Vol 9 (2) ◽  
pp. 80-85
Author(s):  
C.I. Mikhaylenko ◽  
Yu.R. Valeeva
Keyword(s):  
Numerical Simulation ◽  
Mathematical Model ◽  
Disperse System ◽  
Dispersion Medium ◽  
Solid Particles ◽  
Pressure Waves ◽  
Dispersed Particles ◽  
Coagulation Of Particles ◽  
Dispersed Medium ◽  
The Impact

A mathematical model for a disperse system of gas-solid particles when passing pressure waves is decribed. The following assumptions are made: dispersed particles are capable of coagulation with increasing concentration; the dispersed particles are acted upon by the Stokes forces on the side of the dispersion medium and by gravity. The results of numerical simulation of the processes of sedimentation of a dispersed medium are presented. It is shown that one of the mechanisms of precipitation of fine disperced medium can be coagulation of particles during the passage of pressure waves.

scholarly journals An SVEIRE Model of Tuberculosis to Assess the Effect of an Imperfect Vaccine and Other Exogenous Factors

Mathematics ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 327 ◽  
Author(s):  
Fatima Sulayman ◽  
Farah Aini Abdullah ◽  
Mohd Hafiz Mohd
Keyword(s):  
Numerical Simulation ◽  
Mathematical Model ◽  
Disease Burden ◽  
Backward Bifurcation ◽  
Effective Control ◽  
General Effect ◽  
Tuberculosis Transmission ◽  
Proposed Model ◽  
Exogenous Factors ◽  
The Impact

This study extends a deterministic mathematical model for the dynamics of tuberculosis transmission to examine the impact of an imperfect vaccine and other exogenous factors, such as re-infection among treated individuals and exogenous re-infection. The qualitative behaviors of the model are investigated, covering many distinct aspects of the transmission of the disease. The proposed model is observed to show a backward bifurcation, even when Rv<1. As such, we assume that diminishing Rv to less than unity is not effective for the elimination of tuberculosis. Furthermore, the results reveal that an imperfect tuberculosis vaccine is always effective at reducing the spread of infectious diseases within the population, though the general effect increases with the increase in effectiveness and coverage. In particular, it is shown that a limited portion of people being vaccinated at steady-state and vaccine efficacy assume a equivalent role in decreasing disease burden. From the numerical simulation, it is shown that using an imperfect vaccine lead to effective control of tuberculosis in a population, provided that the efficacy of the vaccine and its coverage are reasonably high.

A MATHEMATICAL MODEL TO STUDY THE IMPACT OF MINING ACTIVITIES AND POLLUTION ON FOREST RESOURCES AND WILDLIFE POPULATION

2017 ◽  
Vol 25 (02) ◽  
pp. 207-230 ◽  
Author(s):  
KUMARI JYOTSNA ◽  
ABHINAV TANDON
Keyword(s):  
Numerical Simulation ◽  
Mathematical Model ◽  
Environmental Pollution ◽  
Forest Resources ◽  
Mining Activities ◽  
Nonlinear Mathematical Model ◽  
Wildlife Population ◽  
Constant Rate ◽  
The Impact ◽  
Impact Of Mining

In this paper, we develop a nonlinear mathematical model that investigates the impact of mining activities and pollution on forest resources and wildlife population. It is assumed that concentration of pollutants grows in the environment at a constant rate and also augments due to different mining activities prevailing in the forest area. The model is formulated in terms of differential equations and analyzed using elements of stability theory and numerical simulation. The obtained results depict that both forest resources as well as wildlife population get very much affected, either directly or indirectly, due to mining activities and environmental pollution. It is being concluded that, in order to save forests, an ecological balance is required to be maintained among forest resources, forest-dependent wildlife population, mining activities and environmental pollution.

The Impact of Light Polarisation on Light Field of Scenes with Multiple Reflections

2020 ◽  
pp. 108-115 ◽  
Author(s):  
Vladimir P. Budak ◽  
Anton V. Grimaylo
Keyword(s):  
Mathematical Model ◽  
Light Field ◽  
Global Illumination ◽  
Multiple Reflections ◽  
Software Environment ◽  
The Monte Carlo Method ◽  
Mueller Matrices ◽  
Volume Integration ◽  
The Impact

The article describes the role of polarisation in calculation of multiple reflections. A mathematical model of multiple reflections based on the Stokes vector for beam description and Mueller matrices for description of surface properties is presented. On the basis of this model, the global illumination equation is generalised for the polarisation case and is resolved into volume integration. This allows us to obtain an expression for the Monte Carlo method local estimates and to use them for evaluation of light distribution in the scene with consideration of polarisation. The obtained mathematical model was implemented in the software environment using the example of a scene with its surfaces having both diffuse and regular components of reflection. The results presented in the article show that the calculation difference may reach 30 % when polarisation is taken into consideration as compared to standard modelling.

Particularities of the independent auditor's report on reliability of accounting (financial) statements for 2019: COVID-19 as qualitatively essential information (Part 2)

2020 ◽  
Vol 23 (7) ◽  
pp. 777-799
Author(s):  
O.I. Shvyreva ◽  
Z.I. Kruglyak ◽  
A.V. Petukh
Keyword(s):  
Financial Reporting ◽  
Financial Statements ◽  
Economic Situation ◽  
Risk Disclosure ◽  
Essential Information ◽  
Logical Method ◽  
Annual Reporting ◽  
The Face ◽  
Key Aspects ◽  
The Impact

Subject. This article discusses the issues related to the practice of financial reporting in the face of uncertainties caused by the coronavirus contagion, as well as the specifics of the audit strategy and formation of an audit opinion on this reporting. Objectives. The article aims to identify the quality characteristics of financial reporting prepared in the context of the COVID-19 pandemic and justify the key aspects of assurance engagement completion in an extremely uncertain epidemiological and economic situation. Methods. For the study, we used an abstract-logical method, content analysis techniques, systematization, and classification. Results. Analyzing the impact of the extremely uncertain epidemiological and economic situation on financial statements, the article clarifies aspects of disclosure of events after the reporting date and threats to business continuity in the annual reporting of economic entities. The article identifies possible alternative procedures and algorithms to obtain proper evidence when it is insufficient in the face of the inability to meet certain audit standards requirements in a remote audit environment. The article defines the impact of COVID-19 risk disclosure on the structure of the audit report and opinion. Relevance. The results of the study can be used in the practical activities of economic entities that prepare financial statements in the face of significant uncertainty, as well as auditors and audit organizations.

Toxic Political Leadership and the Problems of Professionals in Free State Municipalities

2019 ◽  
Vol 48 (1) ◽  
Author(s):  
David Matheakuena Mohale
Keyword(s):  
Good Governance ◽  
Political Leadership ◽  
Primary Source ◽  
Free State ◽  
Audit Report ◽  
Theoretical Understanding ◽  
Number Of Factors ◽  
Auditor General ◽  
Appointed Officials ◽  
The Impact

The 2016–17 Audit Report by the Auditor General points to the deterioration in audit results of South African municipalities. This deterioration confirms the perennial dysfunctionality of municipalities, at least from the governance perspective. Corporate governance is a function of leadership. Municipal councils are, therefore, responsible for the overall performance of municipalities they lead. Sound regulatory framework, good plans, clear strategies, policies, and systems are inadequate if not supported by highly gifted and ethical leadership. The Auditor General’s Audit Report suggests that local government struggles the most in the area of ethics. The Principal-Agent Theory argues that appointed officials are more likely to subvert the interests of an organisation. However, this article argues that the primary source of problems in municipalities is a combination of ineptitude and unethical political leadership taking root. This conclusion is based on the empirical comparative cases of eight municipalities in the Free State Province.  The conduct of councillors makes it difficult to attract and retain professionals in municipalities, resulting in notable deficiencies in the delivery of services. Essentially, councillors are the root cause for governance failure in municipalities arising from a number of factors. Findings in this study contribute towards the understanding of the impact of leadership in the failure of municipalities to meet good governance and developmental objectives. Further, they deepen the theoretical understanding of the political-administrative interface.

Principles and approaches for numerical modelling of sediment transport in sewers

1995 ◽  
Vol 31 (7) ◽  
pp. 107-115 ◽  
Author(s):  
Ole Mark ◽  
Cecilia Appelgren ◽  
Torben Larsen
Keyword(s):  
Mathematical Model ◽  
Sediment Transport ◽  
Numerical Modelling ◽  
Simple Application ◽  
Sewer Systems ◽  
Sediment Deposits ◽  
Model Mouse ◽  
Modelling Approaches

A study has been carried out with the objectives of describing the effect of sediment deposits on the hydraulic capacity of sewer systems and to investigate the sediment transport in sewer systems. A result of the study is a mathematical model MOUSE ST which describes sediment transport in sewers. This paper discusses the applicability and the limitations of various modelling approaches and sediment transport formulations in MOUSE ST. Further, the paper presents a simple application of MOUSE ST to the Rya catchment in Gothenburg, Sweden.

Analyzing the Impact of Healthy Behavior on Weight Change with a Provable Mathematical Model (Preprint)

2020 ◽  
Author(s):  
Ayan Chatterjee ◽  
Ram Bajpai ◽  
Pankaj Khatiwada
Keyword(s):  
Physical Activity ◽  
Mathematical Model ◽  
Health Behavior ◽  
Weight Change ◽  
Simulated Data ◽  
Negative Behavior ◽  
Healthy Behavior ◽  
Healthy Habits ◽  
Lifestyle Diseases ◽  
The Impact

BACKGROUND Lifestyle diseases are the primary cause of death worldwide. The gradual growth of negative behavior in humans due to physical inactivity, unhealthy habit, and improper nutrition expedites lifestyle diseases. In this study, we develop a mathematical model to analyze the impact of regular physical activity, healthy habits, and a proper diet on weight change, targeting obesity as a case study. Followed by, we design an algorithm for the verification of the proposed mathematical model with simulated data of artificial participants. OBJECTIVE This study intends to analyze the effect of healthy behavior (physical activity, healthy habits, and proper dietary pattern) on weight change with a proposed mathematical model and its verification with an algorithm where personalized habits are designed to change dynamically based on the rule. METHODS We developed a weight-change mathematical model as a function of activity, habit, and nutrition with the first law of thermodynamics, basal metabolic rate (BMR), total daily energy expenditure (TDEE), and body-mass-index (BMI) to establish a relationship between health behavior and weight change. Followed by, we verified the model with simulated data. RESULTS The proposed provable mathematical model showed a strong relationship between health behavior and weight change. We verified the mathematical model with the proposed algorithm using simulated data following the necessary constraints. The adoption of BMR and TDEE calculation following Harris-Benedict’s equation has increased the model's accuracy under defined settings. CONCLUSIONS This study helped us understand the impact of healthy behavior on obesity and overweight with numeric implications and the importance of adopting a healthy lifestyle abstaining from negative behavior change.

scholarly journals Nanofluid flow containing carbon nanotubes with quartic autocatalytic chemical reaction and Thompson and Troian slip at the boundary

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Muhammad Ramzan ◽  
Jae Dong Chung ◽  
Seifedine Kadry ◽  
Yu-Ming Chu ◽  
Muhammad Akhtar
Keyword(s):  
Mathematical Model ◽  
Carbon Nanotubes ◽  
Drag Force ◽  
Chemical Reaction ◽  
Slip Velocity ◽  
Volume Fraction ◽  
Surface Drag ◽  
Nanofluid Flow ◽  
Velocity Parameter ◽  
The Impact

Abstract A mathematical model is envisioned to discourse the impact of Thompson and Troian slip boundary in the carbon nanotubes suspended nanofluid flow near a stagnation point along an expanding/contracting surface. The water is considered as a base fluid and both types of carbon nanotubes i.e., single-wall (SWCNTs) and multi-wall (MWCNTs) are considered. The flow is taken in a Dacry-Forchheimer porous media amalgamated with quartic autocatalysis chemical reaction. Additional impacts added to the novelty of the mathematical model are the heat generation/absorption and buoyancy effect. The dimensionless variables led the envisaged mathematical model to a physical problem. The numerical solution is then found by engaging MATLAB built-in bvp4c function for non-dimensional velocity, temperature, and homogeneous-heterogeneous reactions. The validation of the proposed mathematical model is ascertained by comparing it with a published article in limiting case. An excellent consensus is accomplished in this regard. The behavior of numerous dimensionless flow variables including solid volume fraction, inertia coefficient, velocity ratio parameter, porosity parameter, slip velocity parameter, magnetic parameter, Schmidt number, and strength of homogeneous/heterogeneous reaction parameters are portrayed via graphical illustrations. Computational iterations for surface drag force are tabulated to analyze the impacts at the stretched surface. It is witnessed that the slip velocity parameter enhances the fluid stream velocity and diminishes the surface drag force. Furthermore, the concentration of the nanofluid flow is augmented for higher estimates of quartic autocatalysis chemical.

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