gistfile1.txt

irb(main):003:0> require 'time'
=> true
irb(main):008:0> Time.strptime("2014-02-06T11:20:16.898", '%Y-%m-%dT%H:%M:%S')
=> 2014-02-06 11:20:16 +0900
irb(main):009:0> Time.strptime("2014-02-06T11:20:16Z", '%Y-%m-%dT%H:%M:%S%z')
=> 2014-02-06 11:20:16 UTC
irb(main):010:0> Time.strptime("2014-02-06T11:20:16.898Z", '%Y-%m-%dT%H:%M:%S%z')
ArgumentError: invalid strptime format - `%Y-%m-%dT%H:%M:%S%z'
     from /Users/orange/.rbenv/versions/2.0.0-p247/lib/ruby/2.0.0/time.rb:394:in `strptime'
     from (irb):10
     from /Users/orange/.rbenv/versions/2.0.0-p247/bin/irb:12:in `<main>'
irb(main):011:0> Time.parse("2014-02-06T11:20:16.898Z", '%Y-%m-%dT%H:%M:%S%z')
=> 2014-02-06 11:20:16 UTC