Information Technology Reference
In-Depth Information
broken down and specified makes it possible to have an algorithm
for space launch.
Let's look at this in more depth. When considering a space
launch, scientists first identify all variables that might be relevant to
the mission. They also identify output variables for all of the desired
results, such as how much fuel should be pumped to the rocket en
gines at any moment or when a signal should be sent to separate one
stage of the rocket from the others. All these variables are then re
lated through equations or other relationships. When this basic
framework is complete, attention turns to determining the steps, or
the algorithm, needed to perform the various computations. This
process is called
modeling
, or mathematical modeling, and such
work provides the background needed to write computer programs
to support the application—in this case, the launching of astronauts
into space.
Also, well before the launch ever takes place, these same vari
ables and equations can be used to determine what results might oc
cur under various circumstances. For example, using assumptions
about weight, rocket thrust, air pressures, and the like, computa
tions could indicate whether a rocket would achieve earth orbit, and
where that orbit might be. This type of hypothesizing, based on
models, is called
simulation
, and simulations can provide a great
deal of information on what might be—based on possible values for
variables and assumed variable relationships and equations.
In the case of the launching of astronauts into space, the models
and simulations are extensive and complex. However, physical laws
provide a scientific background that guides the development of de
tailed algorithms and computer programs. The work is difficult, but
the field is known for producing adequate instructions that enable
computers to handle the computations involved in the design, moni
toring, and control of the rocket systems required for rocket travel.
As a result, it has been possible to launch astronauts into space.
On the other hand, no one has produced an adequate algorithm
for predicting the stock market. This lack of success to date, how
ever, has not been for lack of trying. Magazine articles and televi
sion programs regularly highlight interviews with various econo
mists, investment consultants, and analysts who have developed a
particular model for charting stocks and making predictions. These
folks track a remarkable number of quantitative and qualitative
