title: Always Keep One Section Open Using AngularUI Collapse
body: <p>Does any one know how to modify the Angular UI to only keep one section open like the jQuery Accordion?</p>
  
  <p>Here is the Plunker code: <a href="http://plnkr.co/edit/zv8D1QdDs55iJ47UJhtM?p=preview" rel="nofollow">http://plnkr.co/edit/zv8D1QdDs55iJ47UJhtM?p=preview</a></p>