1 Clinical Psychologist: Doctorate Degree in Psychology (4 to 7 years of graduate school) 2  Industrial-Organizational Psychologist: Master's Degree (2 to 3 years of graduate school)  Forensic Psychologist: Master's Degree (2 to 3 years of graduate school); a doctoral degree is recommended.
Submarine Propulsion Systems. During World War II, most American submarines were powered by diesel-electric systems. This was a departure from earlier submarine power systems, which were direct drive types, little changed from the earliest boats. In this direct-drive power system, the diesel engine is directly connected to the propeller shaft.
Nuclear generators need no oxygen, so a nuclear sub can stay underwater for weeks at a time. Also, because nuclear fuel lasts much longer than diesel fuel (years), a nuclear submarine does not have to come to the surface or to a port to refuel and can stay at sea longer.Nuclear subs and aircraft carriers are powered by nuclear reactors that are nearly identical to the reactors used in commercial power plants.lso, because nuclear fuel lasts much longer than diesel fuel (years), a nuclear submarine does not have to come to the surface or to a port to refuel and can stay at sea longer. Nuclear subs and aircraft carriers are powered by nuclear reactors that are nearly identical to the reactors used in commercial power plants.