An academic community platform provides functions like Facebook, but it targets academic researchers only, providing a space for peer communication and discussion. Generally, it also provides functions for creating resumes and publication lists.
By participating in and managing academic communities, you can promote your research results, find research partners, and stay up to date with the latest research issues.
As advertised on the website (find and share research) ResearchGate is a research sharing platform that allows you to search for journal articles (this function supports the Boolean logic, AND/OR), join fan pages and setup your personal page, etc. Take a look at NCKU's ResearchGate page.
A social networking website for posting jobs and job seekers. Although LinkedIn is not exclusive to academic communities, joining LinkedIn can facilitate academic exchange and promotion. Take a look at NCKU's LinkedIn page.