It is estimated that there are currently around 150,000 Japanese last names used in Japan today. A list of the top 100 surnames comprise almost one third the population: Common Japanese Surnames
Zoning, the regulation of the use of real property by local government, restricts a particular territory to residential, commercial, industrial, or other uses. The local governing body considers the character of the property as well as its fitness for particular uses.
Zoning provides the ability to only condition those rooms that need heating or cooling and does not allow conditioned air into those zones not requiring it. Zoning does this through a series of components, the first being motorized dampers that open and close based on the demands of the zone thermostats.