angularjs的select使用及默认选中设置

<label for="_sel_show_hours">是否显示课时数</label>

<select id="sel_show_hours" ng-model="standardCourse.showHours" >

<option value="1" ng-selected = "1">显示</option>

<option value="0">不显示</option>
</select> 

$stateProvider.state('home.standardCourseAdd', {

    url: "/standardCourse/add",

    templateUrl: "/partials/ace/standardCourse/add.html",

    controller: function ($rootScope, $http, $scope, $location, $anchorScroll, $stateParams, $state, $timeout, $compile, Upload) {

      fnPost($scope, $state, $http, {'name': ''}, '/standardCourse/toAdd.do', function (success, data) {

        $scope.standardCourse = data.entity;

        $scope.standardCourse.showHours= '1';
      });