var outerPane = $details.find(".details-pane-outer"),
    didScroll = false;

$(window).scroll(function() {
    didScroll = true;
});

setInterval(function() {
    if ( didScroll ) {
        didScroll = false;
        // Check your page position and then
        // Load in more results
    }
}, 250);

http://ejohn.org/blog/learning-from-twitter/

Another approach that helps saving the overhead calls of the scroll event and the subsequent code.

Substitute for the scroll event

javascript, js, jquery

jQuery