diff --git a/app/controllers/seminars_controller.rb b/app/controllers/seminars_controller.rb
index af34445..36ed4ce 100644
--- a/app/controllers/seminars_controller.rb
+++ b/app/controllers/seminars_controller.rb
@@ -163,7 +163,7 @@ class SeminarsController < ApplicationController
           @seminar.unassigned_seminar_signup_ids <<  @seminar_signup.id.to_s
           @seminar.save
         end
-        extra_text = "<br>#{I18n.t('seminar_signup.serial_number')}: #{@seminar_signup.serial_number}"
+        extra_text = "<br>#{I18n.t('seminar_signup.serial_number')}: #{@seminar_signup.display_serial_number}"
         if params['seminar_signup']['status']=='C'
           status_param = '&status='
           send_mail('submission',params[:seminar_signup][:email],params[:seminar_signup][:seminar_main_id],extra_text)
@@ -171,7 +171,7 @@ class SeminarsController < ApplicationController
           status_param = ''
           send_mail('signup',params[:seminar_signup][:email],params[:seminar_signup][:seminar_main_id],extra_text)
         end
-        redirect_to "#{params[:referer_url]}/?method=signup_ok#{status_param}&serial_number=#{@seminar_signup.serial_number}"
+        redirect_to "#{params[:referer_url]}/?method=signup_ok#{status_param}&serial_number=#{@seminar_signup.display_serial_number}"
       else
         if !@signup.blank?
          redirect_to "#{params[:referer_url]}", :notice => 'mail已存在'
diff --git a/app/views/seminars/con_upload.html.erb b/app/views/seminars/con_upload.html.erb
index a0f47a3..52532ef 100644
--- a/app/views/seminars/con_upload.html.erb
+++ b/app/views/seminars/con_upload.html.erb
@@ -19,7 +19,7 @@
 <% if @seminar.contribute_start_date <= @time_now and ( @seminar.contribute_end_date.nil? or @seminar.contribute_end_date+1 >= @time_now ) %>
 	<% begin %>
 	<% if !session[:seminar_signup_id].blank? %>
-	<%=t('seminar_signup.serial_number') %>: <%=@seminar_signup.serial_number rescue ""%>
+	<%=t('seminar_signup.serial_number') %>: <%=@seminar_signup.display_serial_number rescue ""%>
 	<a href="<%= OrbitHelper.url_to_show(@seminar.to_param) %>?method=con_logout&con_no=<%= @seminar.id %>" class='btn btn-primary'><%= t('seminar_signup.logout') %></a>
 
 	<table class="table table-hover table-striped seminar-index">