Just a short notice for the paper that has been published very recently. Now it is free of charge until October 2, 2016.
This paper was submitted on last November, and kept in the Elsevier system more than 6 months with the status of “under review”. Reviewing for 6 month!!! I complained about the situation (not push Elsevier for acceptance but just push them for quick decision) from last March, roughly once a month. Then finally the comments from the reviewer came up on June. We made quick response to the comments, because the comments are just easy. However, we waited for another month to get the final decision… Finally the paper has come up on-line.
Nevertheless, the paper has been published.