Ruby's skills in Japanese-to-UTF-8 and halfwidth Conversion

1. Japanese to UTF-8
Differences between Iconv. new ('cp932', 'utf-8') and Iconv. new ('shift _ jis ', 'utf-8')
Iconv. new ('shift _ jis ', 'utf-8') does not support the following formats:
When bytes 001-18 XXXXXXX, you can only replace the bytes in the character escape with No.
However, Iconv. new ('cp932', 'utf-8') supports.
2. halfwidth and fullwidth Conversion
See the following code:
Require "jcode"
$ Cov. iconv (year. to_s.tr ('0-9', '0-9') + 'Year' + month. to_s.tr ('0-9', '0-9') + 'monthly Business Report quota ')