Off-road vehicleAn off-road vehicle (ORV), sometimes referred to as an off-highway vehicle (OHV), overland vehicle, or adventure vehicle, is considered to be any type of vehicle which is capable of driving off paved or gravel surfaces, such as trails and forest roads that have rough and low traction surfaces. These vehicles are generally characterized by having large tyres with deep, open treads, a flexible suspension, or even caterpillar tracks. Because of their versatility, several types of motorsports involve racing off-road vehicles.
Hybrid vehicleA hybrid vehicle is one that uses two or more distinct types of power, such as submarines that use diesel when surfaced and batteries when submerged. Other means to store energy include pressurized fluid in hydraulic hybrids. Hybrid powertrains are designed to switch from one power source to another to maximize both fuel efficiency and energy efficiency. In hybrid electric vehicles, for instance, the electric motor is more efficient at producing torque, or turning power, while the combustion engine is better for maintaining high speed.
Range extenderA range extender is a fuel-based auxiliary power unit (APU) that extends the range of a battery electric vehicle by driving an electric generator that charges the vehicle's battery. This arrangement is known as a series hybrid drivetrain. The most commonly used range extenders are internal combustion engines, but fuel-cells or other engine types can be used. Range extender vehicles are also referred to as extended-range electric vehicles (EREV), range-extended electric vehicles (REEV), and range-extended battery-electric vehicle (BEVx) by the California Air Resources Board (CARB).
EnumerationAn enumeration is a complete, ordered listing of all the items in a collection. The term is commonly used in mathematics and computer science to refer to a listing of all of the elements of a set. The precise requirements for an enumeration (for example, whether the set must be finite, or whether the list is allowed to contain repetitions) depend on the discipline of study and the context of a given problem. Some sets can be enumerated by means of a natural ordering (such as 1, 2, 3, 4, ...
Recursively enumerable languageIn mathematics, logic and computer science, a formal language is called recursively enumerable (also recognizable, partially decidable, semidecidable, Turing-acceptable or Turing-recognizable) if it is a recursively enumerable subset in the set of all possible words over the alphabet of the language, i.e., if there exists a Turing machine which will enumerate all valid strings of the language. Recursively enumerable languages are known as type-0 languages in the Chomsky hierarchy of formal languages.
