Passenger Capacity and Safety: Investigating the Likelihood of COVID-19 Transmission in Public Transport Modes within Makurdi Metropolis

Following its outbreak in the Wuhan region of China, the spread of Corona Virus (COVID-19) across the world has threatened national and local authorities or policy makers and transport experts due to its effects on human mobility. This study investigated the transmissibility of COVID-19 among passengers in transit using public transport modes in Makurdi metropolis. Analytical simulation using stochastic search method called Genetic Algorithm (GA) technique was used to simulate the transmissibility of the infectious disease within enclosed spaces of transport modes based on layouts and capacities. The sum of arithmetic sequence was used as the objective function of individual arrivals in each mode, it was minimised to obtain optimum safe capacity. Capacities of public transport modes were subdivided into; Normal, Above Normal and Below Normal (50% of Normal). Findings of the experiments indicated that optimum safe capacity of minibuses, taxies, tricycles and motorcycles used in Makurdi metropolis were at 8, 3, 2 and 1 person respectively. This occurred at 50% capacity which agreed with findings of previous studies. An efficient and sustainable public transport policy framework was designed for policy makers and transport experts to help achieve safe travel and healthier living in Makurdi metropolis during the COVID-19 era. Keywords— COVID-19 transmission, Makurdi Metropolis, Modal Split, Mode capacity, Passenger Safety, Public Transport.

PROVIDING A DEPENDABLE OPERATION OF THE DATA PROCESSING SYSTEM WITH INTERVAL CHANGES IN THE FLOW CHARACTERISTICS BASED ON ANALYTICAL SIMULATIONS

The article proposes a new approach for adjusting the parameters of computing nodes being a part of a data processing system based on analytical simulation of a queuing system with subsequent estimation of probabilities of hypotheses regarding the computing node state. Methods of analytical modeling of queuing systems and mathematical statistics are used. The result of the study is a mathematical model for assessing the information situation for a computing node, which differs from the previously published system model used. Estimation of conditional probabilities of hypotheses concerning adequate data processing by a computing node allows making a decision on the need of adjusting the parameters of a computing node. This adjustment makes it possible to improve the efficiency of working with tasks on the computing node of the data processing system. The implementation of the proposed model for adjusting the parameters of the computer node of the data processing system increases both the efficiency of process applications on the node and, in general, the efficiency of its operation. The application of the approach to all computing nodes of the data processing system increases the dependability of the system as a whole.

Analytical simulation of time dependent electromagneto-hydrodynamic flow of Williamson fluid due to oscillatory curved convectively heated Riga surface with variable thermal conductivity and diffusivity

The main objective of the present article is to provide an analytical simulation for time dependent boundary layer flow of non-Newtonian Williamson fluid due to stretchable curved oscillatory Riga surface. Also the characteristics of heat and mass transport are studied under the influence of variable thermal conductivity and diffusivity along with convective heat and mass boundary conditions. Additionally, energy equation is also characterized with the impact of heat production. Curvilinear coordinate scheme is followed to attain the boundary layer expressions for the flow model. The governing nonlinear partial differential equations are solved analytically via homotopy analysis method (HAM). Graphs are plotted to examine comprehensively the consequences of various concerned parameters like modified magnetic parameter and radius of curvature, Williamson fluid parameter, relation of the surface's oscillating frequency to its stretching rate constant, Prandtl number, variable conductivity and heat production parameters, Schmidt number and variable diffusivity parameter on concentration, temperature, pressure and velocity profile. Also the outcomes of afore said variables on surface drag force, rate of temperature and mass transmission (Nusselt and Sherwood numbers) are shown in tabular form. The liquid velocity amplitude is enhanced with modified magnetic parameter and shows opposite behavior for Williamson fluid parameter.

Mathematical simulation of air-water flow along Ski Jump Jet

In the present study, using a quasi 3D analytical simulation, air concentration distribution in ski jump generated jet is calculated. A numerical simulation is also performed to verify the results of the analytical model in parallel with the available experimental and another analytical data. By solving continuity and momentum equations in case of air-water flow for three different cases, it was confirmed that the air concentrations along the ski jet are uniquely linked to the relative black water core length. Results showed that the black water core length is also influenced by the approach flow depth, Froude number, geometrical parameters of ski jump and the chute bottom angle. Finally, an analytical equation is proposed to predict the air concentration distribution along the ski jump jet regarding different hydraulic and geometric parameters. By calculating the velocity profiles along the jet, it showed that increasing the air concentration reduces the jet velocity profile.

Development of the survivability indicators forecasting method of the special-purpose system executive element based on analytical and stochastic simulation of a conflict situation

The developed method for forecasting the survivability indicators of the executive element of a special-purpose system based on analytical-stochastic simulation of a conflict situation is presented. The purpose of the method was to solve the problem of preserving and rational use of the resource of the executive elements to achieve the desired effect of the functioning of special-purpose systems. The method is sensitive to the description of the patterns of changes in the survivability and efficiency indicators of the system. It is supposed to compare the predicted value of the survivability indicator with its criterion value and forecast the time when the system loses the ability to effectively perform tasks. The survivability indicator is the mathematical expectation of the number of executive elements of a special-purpose system, which retained their ability to perform tasks as intended during a conflict situation. Based on the results of the study, the values of the time characteristics of a conflict situation were obtained, in particular, the duration of the corresponding states of the executive element: preparation, waiting, implementation. Graph-analytical simulation provides a solution to the problem of forecasting the time when the loss of executive elements leads to the system’s inability to effectively perform tasks. Checking of the adequacy of the method showed that the confidence interval of the discrepancy between the calculation results of other methods with a confidence level of 0.9 does not exceed 0.095, and no contradictions between the methods were found. The proposed method provides an increase in the efficiency of determining the corresponding indicators within 8–11 % and reliability by 22 %. The possibility to determine the required reserve and the time for introducing executive elements into the system can provide a justification for how they are used to maintain the required level of efficiency of a special-purpose system.

ANALYTICAL MODEL OF PACKET TRANSMISSION OF SPEECH AND DATA IN HF RADIO CHANNELS IN A COMPLEX SIGNAL-INTERFERENCE ENVIRONMENT

The author has carried out an analytical simulation of the process of signal formation and processing in the HF channel during packet transmission of speech and data in a complex signal-interference environment. The totality of the result obtained can be the basis for the development of complex mathematical models of HF channels.