def convert_mjd_to_date(mjd)
      y_ = ((mjd - 15078.2) / 365.25).to_i
      m_ = ((mjd - 14956.1 - (y_ * 365.25).to_i) / 30.6001).to_i
      d  = mjd - 14956 - (y_ * 365.25).to_i - (m_ * 30.6001).to_i
      k  = (m_ == 14 || m_ == 15) ? 1 : 0
      y  = y_ + k
      m  = m_ - 1 - k * 12
      return Date.new(1900 + y, m, d)
    end
def convert_mjd_to_date(mjd)
      y_ = ((mjd - 15078.2) / 365.25).to_i
      m_ = ((mjd - 14956.1 - (y_ * 365.25).to_i) / 30.6001).to_i
      d  = mjd - 14956 - (y_ * 365.25).to_i - (m_ * 30.6001).to_i
      k  = (m_ == 14 || m_ == 15) ? 1 : 0
      y  = y_ + k
      m  = m_ - 1 - k * 12
      return Date.new(1900 + y, m, d)
    end
ARIB STD-B10 2, appendix-C