This research aim to recognize relationship between stresses
and Self-efficacy at college education students in Albaath
university, It also aimed to recognizing the levels of self-efficacy
and life stresses at them, and known differences of means
on
stresses and Self-efficacy according to Specialization school. The
research sample consist of (186) student male and female at
college education in Albaath University. To achieve this aims, the
researcher used the following materials: Test stresses and selfefficacy
prepared by the researcher.
The main objective of this article is to study the influence of static and dynamic
behavior on the occurrence of contact fatigue on spur gear tooth. For this end, a dynamic
model of geared transmission in one degree of freedom, with Crossland crite
rion, are used.
The motion equation is analyzed step par step in the time in order to determine the
dynamic load in all contact points on teeth profile. In this way, the time-varying dynamic
loads on tooth flanks are determined and the subsurface stress components can be derived
from the classic Hertzian theory.
Ship collision accidents are considered of the most serious incidents, due to the
subsequent disastrous results both in terms of economic losses in ships and cargo, and the
loss of human life as well as the great environmental pollution caused by i
t. Therefore,
continuous efforts are being made by research centers in order to understand the structural
response of the hull as a result of these incidents and accurately analyzed.
This research is interested in assessing the residual structural strength of a ship
exposed to collision through the internal energy and the various structural stresses
generated within it. The case is modeled for an oil tanker exposed to collision by the
bulbous bow of another vessel moves at different speeds and different angles. The
structural strength of the middle section of the struck ship was analyzed based on the
numerical methods using Ansys Dynamic Explicit program. Which allowed the
development of a clear vision for the structural changes and internal stresses energy with
time during the collision process.
In this article we studied two types of teeth, spherical and
conical one. We compared the results with a previous study for the
flat tooth. the study of stresses field under these three teeth show
that in the soft rocks we prefer to use conical to
oth because it is
easy to be Implanted in the rock, and this was confirmed by the
values of stresses under the tooth. Either in hard rock and due to
our need for big values of pressure to shatter the rock we prefer to
use spherical tooth because of its property of forming tow cons of
stresses under tooth and therefore can be good in drilling hard
rock..
