diff --git a/app/controllers/exercise_questions_controller.rb b/app/controllers/exercise_questions_controller.rb
index b231d6af7..77cc108b3 100644
--- a/app/controllers/exercise_questions_controller.rb
+++ b/app/controllers/exercise_questions_controller.rb
@@ -350,8 +350,9 @@ class ExerciseQuestionsController < ApplicationController
           @exercise_question.shixun_name = shixun_name
         end
 
-        #当标准答案修改时，如有已提交的学生，需重新计算分数
-        if st_count > 0
+        #当试卷已发布时（试卷的总状态),当标准答案修改时，如有已提交的学生，需重新计算分数.
+
+        if @exercise.exercise_status == 2
           ex_users_committed = @exercise.exercise_users.exercise_user_committed
           if ex_users_committed.size > 0
             ex_users_committed.each do |ex_user|
@@ -587,15 +588,15 @@ class ExerciseQuestionsController < ApplicationController
     if @exercise_question.present?
       @exercise = @exercise_question.exercise
       if @exercise.blank?
-        tip_exception(404)
+        tip_exception(404,"试卷不存在")
       else
         @course = @exercise.course
         if @course.blank?
-          tip_exception(404)
+          tip_exception(404,"课堂不存在")
         end
       end
     else
-      tip_exception(404)
+      tip_exception(404,"试卷问题不存在")
     end
   end
 
diff --git a/app/controllers/graduation_tasks_controller.rb b/app/controllers/graduation_tasks_controller.rb
index a89a81798..545b10e11 100644
--- a/app/controllers/graduation_tasks_controller.rb
+++ b/app/controllers/graduation_tasks_controller.rb
@@ -129,7 +129,7 @@ class GraduationTasksController < ApplicationController
         if @user_course_identity >= Course::STUDENT
           tip_exception(403, "无权限操作")
         elsif complete_works == 0
-          normal_status(-1,"暂无用户提交！")
+          normal_status(-1,"暂无用户提交")
         else
           respond_to do |format|
             format.xlsx{
@@ -164,7 +164,7 @@ class GraduationTasksController < ApplicationController
       @work_count = @work_list.count
       @all_work_count = @work_list.count
       if params[:format] == "xlsx" || params[:format] == "zip"
-        normal_status(-1,"作业未发布")
+        normal_status(-1,"毕设任务未发布")
       end
     end
   end
diff --git a/app/controllers/homework_commons_controller.rb b/app/controllers/homework_commons_controller.rb
index fe2adba45..e595c703e 100644
--- a/app/controllers/homework_commons_controller.rb
+++ b/app/controllers/homework_commons_controller.rb
@@ -106,7 +106,7 @@ class HomeworkCommonsController < ApplicationController
 
     student_works = @homework.all_works
     @all_member_count = student_works.size
-    if @homework.publish_time.nil? || @homework.publish_time > Time.now
+    if @homework.publish_time.blank? || (@homework.publish_time > Time.now)
       @student_works = []
       if params[:format] == "xlsx" || params[:format] == "zip"
         normal_status(-1,"作业未发布")