# File lib/numru/nusdas.rb, line 106
    def time_from_zerotime(vtime, btime, unit)
      case unit.upcase
      when "MINUIT"
        # nothing to do
      when "HOUR"
        vtime *= 60
      when "DAY"
        vtime *= 1440 # 60*24
      else
        raise "sorry unit #{u} is not supported"
      end
      return vtime + btime
    end