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.
The US Navy no longer has nuclear powered cruisers or destroyers. The only nuclear powered surface ships are aircraft carriers. In general, the nuclear powered cruisers/destroyers could achieve speeds in excess of 30 knots (34 Miles Per Hour). Aircraft carriers must be able to achieve the same speed in order for them to be able to launch and recover aircraft. The US Navy no longer has nuclear powered cruisers or destroyers.