There are generally four recognized levels of tests: unit testing, integration testing, component interface testing, and system testing. Tests are frequently grouped by where they are added in the software development process, or by the level of specificity of the test.
fMRI is based on the same technology as magnetic resonance imaging (MRI) -- a noninvasive test that uses a strong magnetic field and radio waves to create detailed images of the body. But instead of creating images of organs and tissues like MRI, fMRI looks at blood flow in the brain to detect areas of activity.edical technology has come so far in recent years that it's now possible for imaging scans to Â­dissect the body into wafer-thin pictures and create three-dimensional models of organs and tissues to find abnormalities and diagnose disease.
In practice, many fuel cells are usually assembled into a stack. Cell or stack, the principles are the same. Top. How do fuel cells work? The purpose of a fuel cell is to produce an electrical current that can be directed outside the cell to do work, such as powering an electric motor or illuminating a light bulb or a city. Because of the way electricity behaves, this current returns to the fuel cell, completing an electrical circuit.