Ember.js在控制器内部处理异步关系

I have 2 models:

我有2个型号：

App.Center = DS.Model.extend({
    name: DS.attr('string'),
    code: DS.attr('string'),
    studies: DS.hasMany('study', {async: true})
});

App.Study = DS.Model.extend({
    center: DS.belongsTo('center'),
    //other data
});
App.Center = DS.M