If you work with a single page application or have some interactive content (such as a slideshow), you can refresh the ads to earn additional impressions. Do note that abuse of refreshing will result in the termination of your account.
Implementation 1: Global Refresh
<div data-mantis-zone="zone1" data-mantis-refresh="true"></div>
Implementation 2: Individual Refresh
Alternatively, you can refresh a single placement by providing the name of the zone.
mantis.push(['display', 'refresh', 'zone2']);