diff --git a/app/controllers/hps_learnings_controller.rb b/app/controllers/hps_learnings_controller.rb
index 50caeac..2e583e5 100644
--- a/app/controllers/hps_learnings_controller.rb
+++ b/app/controllers/hps_learnings_controller.rb
@@ -4,8 +4,9 @@ class HpsLearningsController < ApplicationController
     classes = []
     HpsClass.all.desc(:created_at).each do |hpsclass|
       if hpsclass.hps_lectures.count > 0
+        thumb = hpsclass.course_pic.thumb.url.nil? ? "http://www.placehold.it/150x150/EFEFEF/AAAAAA" : hpsclass.course_pic.thumb.url
         classes << {
-          "course_pic_thumb" => (hpsclass.course_pic.thumb.url rescue "http://www.placehold.it/150x150/EFEFEF/AAAAAA"),
+          "course_pic_thumb" => thumb,
           "course_pic" => (hpsclass.course_pic.url rescue ""),
           "title" => hpsclass.title,
           "category" => hpsclass.category.title,
@@ -29,8 +30,10 @@ class HpsLearningsController < ApplicationController
     lectures = []
     hpsclass.hps_lectures.each do |lecture|
       if !lecture.hps_lecture_file.nil? && !lecture.hps_lecture_file.index_path.nil?
+        
+        thumb = lecture.lecture_pic.thumb.url.nil? ? "http://www.placehold.it/150x150/EFEFEF/AAAAAA" : lecture.lecture_pic.thumb.url
         lectures << {
-          "lecture_pic_thumb" => (lecture.lecture_pic.thumb.url rescue "http://www.placehold.it/150x150/EFEFEF/AAAAAA"),
+          "lecture_pic_thumb" => thumb,
           "lecture_pic" => (lecture.lecture_pic.url rescue ""),
           "subject" => lecture.subject,
           "presenter" => lecture.presenter,