The purpose of this research is to establish a suitable mathematical model for the
study of epidemiology, showing the role of the epidemic threshold which cannot be
distinguished from the data for use by infectious disease experts and public health
.
There has been a growing interest in recent epidemiological models of epidemiology
because of their health and economic effects. Epidemiology (from a mathematical point of
view) is a section of general epidemiology that deals with mathematical modeling in
relation to the need to predict and spread infectious diseases.
In this paper we present a study on the time cost
added to the grid computing as a result of the use of a
coordinated checkpoint / recovery fault tolerance protocol, we aim
to find a mathematical model which determined the suitable time
to save t
he checkpoints for application, to achieve a minimum
finish time of parallel application in grid computing with faults and
fault tolerance protocols, we have find this model by serial
modeling to the goal errors, execution environment and the
chosen fault tolerance protocol all that by Kolmogorov differential
equations.
This study aimed to estimate the height of the Pinus brutia trees in Kafardabeel
forested area- Jableh. Eight mathematical forms (Michailoff, Prodan, Petterson, Parabel,
Korsun, Logarithmic, Freese, Chapman-Richards) were used.
In 2015, the diamet
er of 330 trees at breast height (dbh) were measured, and only
heights of 165 of them were taken. Measurements were carried out in 15 sample plots all
over the study area to cover site variations in altitude, exhibition, gradient and density.
Data were split into two parts: 116 tree (70%) were used for model constrction, while the
remaining trees 49 tree (30%) were used for model validation.
The Results showed that, Parabel had the highest value for the Coefficient of
Determination (R²=0.53) and the lowest value of the relative accuracy (mx%) (17.665%).
That means it was the the best model to calculate tree height using diameter at breast
height. This model can help foresters in forest management planning for study area and
similar sites.
The research focused on the conclusion of a mathematical model to determine the
proportion of nitrogen oxides emitted from the internal combustion engine based on the
equations of chemical interaction of direct and reverse the conventional fuel wit
h the use of
many of the correction coefficients, as well as the possibility of developing this model.
Search to find out the concentration of nitrogen oxides NO changes resulting from the
combustion of fuel in internal combustion engines that run on diesel fuel and gasoline
adopted, during work time, and then transform this relationship to calculate the ratio of the
concentrations according to the angle of rotation of the engine crankshaft.
The third sector of lower Euphrates basin has a great economic importance, but some
lands have gone out of service because of salinization due to the rise of groundwater levels.
Thus, it is very important to solve the ground water issue using new s
cientific techniques.
This research aims to solve the drainage problem in the third sector using a scenario based
on a mathematical model, the results of which allow us design a proper drainage network
comprised of 111 wells scattered all over the study area, with a total abstraction of 269000
m3/day. This will lower the groundwater level, dry the swamps, and decrease the soil
salinity, ensuring a sustainable economic exploitation of agricultural lands.
The equation of towers height calculation carryingpower transmission lines at their
intersection with engineering installation is one of the methods of designing power nets,the
solution of which depends on the traditional method for calculating con
ductors
coordinates. Sometimes this problem becomes so complicated or impossible to solve,
therefore, we have to use the space solution mainly when the wind direction made an angle
with these transmission lines and the points of hanging height difference. In this case it is
better to use the vector method which we used at the present work. We used a
mathematical model to calculate the minimum point coordination of the transmission lines
curves and the minimum distance between the engineering installation and that of these
transmission lines, and the suitable carrying towers heights, a cording to the permissible
electrical equipment laws. So we could find the suitable towers height coordinates by using
the C++ applicable program.
Calculation errors between traditional and vector method reaches high value which
increases with the slope angle increasing of conductors.
The simplified dynamic mathematical model of hybrid stepper motor was studied in this
research. The aim was to simplify the study and to concentrate on certain topic of this subject.
The mathematical model which describes their mechanical and elect
rical dynamic behavior of
the mentioned motor was done. Whereas, the mechanical model can be derived by Newton law,
and electrical model can be derived by Kirchhoff law depending on the electrical equivalent
circuit to each phase.
The objective of this study was to model the Blood Flow into human arm’s
arteries in order to define velocity profile. All steps were based on
computational fluid dynamics .Simplified model for arm’s most important
arteries were made, while primar
y data such as length, diameter, and
velocity were collected for a healthy 40 years old, male , weight 64 Kg with
pulse rate 62 bpm ,and his arteries ranges from 1.6 to 2.6 mm by using
Doppler measurement.Bio dynami
