rails4のサブディレクトリ運用
http://quickhack.net/nom/blog/2012-09-19-rails-with-relative-url-root.html#sec-6
config.ruは
map ActionController::Base.config.relative_url_root || "/" do run Rails.application end
起動は
RAILS_RELATIVE_URL_ROOT='/yourdict' unicorn -p 8080 -E production -D
apacheとかは
ProxyPass /yourdict http://localhost:8080/yourdict ProxyPassReverse /yourdict http://localhost:8080/yourdict
で。