The Question of Drawing a Design Scheme of a Wagon with a Non-Symmetrically Located Freight

Violations of the stability of a wagon with an asymmetrically positioned freight can lead to a threat to the safety of train traffic, the safety of freight on the route and transport facilities. The design diagram of a wagon with an asymmetrically located freight drawn up in the article and the equations obtained in an analytical way, oscillations of the sprung mass of a wagon with an asymmetric arrangement of the freight, characterizing the longitudinal and transverse displacement of the center of mass of the freight, can be used for mathematical modeling of forced vibrations and impact on the track of a wagon with asymmetrically located freight in various operating conditions.

Study of Flow by Varying the Position of Maximum Chamber Thickness on Aerofoil

Aerofoil is a design with a curved exterior that gives the most commendable ratio of lift to drag. The aerofoil which allows for the flow at a margin range of angle has a more remarkable impact on the power spawning from the turbine. The conception and examination for the airfoil Structure have been implemented in the current work to raise the behavior of the flow with a commendatory condition by varying the position of maximum chamber thickness position thereby varying the angle of attack with 5 degrees interval from 0-25 degrees. The best model is studied with surface modifications to increase the flow separation and efficiency of lift.

Three-Dimensional Motion of Tennis Ball

Modern tennis players use a variety of strokes. From the physical point of view, these shots can be classified into eight main groups depending on the way the racket interacts with the tennis ball. These are strokes with top, bottom, side, top-side, and bottom-side rotation, as well as strokes without rotation. These eight interactions lead to eight main types of trajectories at the same initial position and the same initial linear velocity. The main purpose of the study is to determine these trajectories and to describe their advantages and disadvantages in modern competitive tennis. The calculations and graphical images are performed with the MatLab mathematical package

Dynamics of an SEIRS COVID-19 Epidemic Model with Saturated Incidence and Saturated Treatment Response: Bifurcation Analysis and Simulations

In this work, we study the dynamics of the Coronavirus Disease 2019 pandemic using an SEIRS model with saturated incidence and treatment rates. We derive the basic reproduction number R_0 and study the local stability of the disease-free and endemic states. Since the condition R_0<1 for our model does not determine if the disease will die out, we study the backward bifurcation and Hopf bifurcation to understand the dynamics of the disease at the occurrence of a second wave and the kind of treatment measures needed to curtail it. We present some numerical simulations considering the symptomatic and asymptomatic infections and make a comparison with the reported COVID-19 data for Nigeria. Our results show that the limited availability of medical resources favours the emergence of complex dynamics that complicates the control of the outbreak