<ltng:require scripts="{!$Resource.MyCommunity + '/js/myscript.js'}" afterScriptsLoaded="{!c.afterScriptsLoaded}" />

afterScriptsLoaded : function(component, event, helper) {
    console.log("script has loaded");
}

<script data-locker-src="/core/resource/MyCommunity/js/myscript.js" type="text/javascript"></script>