專(zhuān)四晨讀美文：Roles for the Mechanical Engineer

Roles for the Mechanical Engineer
Do you realize that every time you take a step,
the bones in your hip are subjected to forces
between four and five times your body weight?
When you are running, this force is increased further still.
What happens if through disease
a hip-joint ceases to be able to resist such forces?
For many years hip-joints and other body joints
have been replaceable either partially or completely.
It is after all a simple ball and socket joint;
it has certain loads imposed on it;
it needs reliability over a defined life;
it must contain materials suitable for the working environment.
Any engineer will recognize these
as characteristic of a typical engineering problem,
which doctors and engineers have worked together to solve,
in order to bring a fresh lease of life
to people who would otherwise be disabled.
This typifies the way in which engineers work to help people
and create a better quality of life.
The fact that this country
has the most efficient agricultural industry in the world
is another good example.
Mechanical engineers have worked with farmers and biologists
to produce fertilizers, machinery and harvesting systems.
This team effort has now produced crops
uniformly waist high or less
so that they are better suited to mechanical harvesting.
Similar advances with other crops
have released people from hard and boring jobs
for more creative work,
whilst machines harvest crops more efficiently with less waste.
Providing more food for the rapidly increasing population
is yet another role for the mechanical engineer.