diff --git a/app/models/seminar_main.rb b/app/models/seminar_main.rb
index e36f507..92f60e9 100644
--- a/app/models/seminar_main.rb
+++ b/app/models/seminar_main.rb
@@ -296,7 +296,7 @@ class SeminarMain
 end
 def map_seminar_signup_ids(old_seminar_signup_ids)
   if @records_all["seminar_signup_ids"].present?
-    old_seminar_signup_ids.map{|seminar_signup_id| @records_all["seminar_signup_ids"][BSON::ObjectId(seminar_signup_id)]}
+    old_seminar_signup_ids.map{|seminar_signup_id| @records_all["seminar_signup_ids"][BSON::ObjectId(seminar_signup_id)].to_s rescue ""}.select{|t| t.present?}
   else
     []
   end
diff --git a/app/models/seminar_review.rb b/app/models/seminar_review.rb
index ec4e9e1..d2106fe 100644
--- a/app/models/seminar_review.rb
+++ b/app/models/seminar_review.rb
@@ -73,8 +73,8 @@ class SeminarReview
   end
   def get_all_seminar_signup_ids(mode = nil)
     if (self.default_topics.include?("seminar_signup_contributes.description") && self.seminar_main.assign_mode == 1) || mode == 1
-      final_assign_signup_ids = SeminarSession.where(:id.in=>self.seminar_session_ids).pluck(:seminar_signup_ids).flatten rescue []
-      self.seminar_signup_ids - self.remove_seminar_signup_ids + final_assign_signup_ids
+      final_assign_signup_ids = SeminarSession.where(:id.in=>self.seminar_session_ids).pluck(:seminar_signup_ids).flatten.map{|id| id.to_s} rescue []
+      final_assign_signup_ids + self.seminar_signup_ids - self.remove_seminar_signup_ids
     else
       all_seminar_signup_ids
     end
diff --git a/app/views/admin/seminars/_seminar_signup_dashboard.html.erb b/app/views/admin/seminars/_seminar_signup_dashboard.html.erb
index 9549b74..4e32378 100644
--- a/app/views/admin/seminars/_seminar_signup_dashboard.html.erb
+++ b/app/views/admin/seminars/_seminar_signup_dashboard.html.erb
@@ -1,7 +1,7 @@
 <h3 class="pull-left"><%= @seminar.title %></h3>
 <div style="clear: both;"></div>
 <% org_seminar_signups = @seminar_signups %>
-<div style="float: left;width: 50%;">
+<div style="float: left;width: 50%;" class="left_block">
   <h4><%= t("seminar.reviewer") %></h4>
   <% reviewer_show_ids = @seminar.reviewer_show_ids %>
   <% if reviewer_show_ids.nil?
@@ -65,6 +65,14 @@
         </div>
     </div>
     <script type="text/javascript">
+      function add_obj(obj1,obj2){
+        var keys = Object.keys(obj1);
+        var obj = {};
+        keys.forEach(function(k){
+          obj[k] = obj1[k] + obj2[k];
+        });
+        return obj;
+      }
       function generate_pagination(reviewer_id,index=1,start=1,end=1,active=1){
         var pagination = $('<div class="pagination pagination-centered">');
         pagination.append('<div class="pagination"><ul></ul></div>');
@@ -153,13 +161,75 @@
           revert: true,
           handle: ".brand",
           connectWith: ".table tbody",
+          start: function(event, ui){
+            var target = $(event.target);
+            if(target.find("tr[data-id]").length <= 1){
+              target.find(".blank_tr").css("display","");
+            }else{
+              target.find(".blank_tr").css("display","none");
+            }
+            $(".reviewer_block").css("overflow","hidden");
+            if($("#copy_mode_on:checked").length != 0){
+              var clone_obj = ui.item.clone();
+              clone_obj.attr("style","")
+              ui.item.before(clone_obj)
+              window.clone_obj = clone_obj;
+            }else{
+              window.clone_obj = undefined;
+            }
+            parent_left_block = ui.item.parents(".left_block");
+            if(parent_left_block.length != 0){
+              var parent_block = ui.item.parents(".reviewer_block");
+              console.log(parent_left_block);
+              parent_left_block.before(ui.item);
+              window.parent_block = parent_block;
+              ui.item.css("background","#ffffff");
+              window.over_flag = false;
+            }else{
+              window.parent_block = undefined;
+            }
+          },
+          sort: function(event, ui) {
+            if(window.parent_block != undefined){
+              var offset = ui.position;
+              var parent_offset = window.parent_block.offset();
+              if(!window.over_flag){
+                offset = add_obj(ui.position,parent_offset);
+                ui.item.offset(offset);
+              }
+            }
+          },
+          over: function( event, ui ) {
+            if(window.parent_block != undefined && $(this).data("id") != window.parent_block.data("id")){
+              window.over_flag = true;
+            }
+          },
+          stop: function(event, ui){
+            $(".reviewer_block").css("overflow","");
+            ui.item.css("background","");
+          },
           update: function(event, ui) {
+            if(window.clone_obj != undefined){
+              if(window.clone_obj.parent().data("id") == undefined){
+                window.clone_obj.remove();
+              }else if(window.clone_obj.parent().data("id") == ui.item.parent().data("id")){
+                window.clone_obj.remove();
+              }else if(ui.item.parent().data("id") == undefined){
+                window.clone_obj.remove();
+              }
+            }
             var target = $(event.target);
             var mode = "";
             var id = target.data("id");
             var signup_id = ui.item.data("id");
-            if(ui.item.parent().data("id") == id){
+            if(target.find("tr[data-id=\""+signup_id+"\"]").length != 0){
               mode = "append";
+              if(target.find("tr[data-id=\""+signup_id+"\"]").length > 1){
+                var target_signups= target.find("tr[data-id=\""+signup_id+"\"]");
+                for(var i=1;i<target_signups.length;i++){
+                  target_signups.eq(i).remove();
+                }
+              }
             }else{
               mode = "remove";
             }
@@ -170,14 +240,17 @@
             }
             if(id != undefined){
               $.post("<%=admin_seminar_update_seminar_review_path%>",{id: id,mode: mode,signup_id: signup_id}).done(function(data){
-                console.log(data);
               })
             }
           }
         });
       }
       $(document).ready(function(){
-        
+        $("tbody").each(function(i,v){
+          if($(v).find("tr[data-id]").length != 0){
+            $(v).find("tr.blank_tr").css("display","none");
+          }
+        })
         init_func();
       })
       $(window).resize(function(){
diff --git a/app/views/admin/seminars/_seminar_signup_render_table.html.erb b/app/views/admin/seminars/_seminar_signup_render_table.html.erb
index 86051c5..e8f7001 100644
--- a/app/views/admin/seminars/_seminar_signup_render_table.html.erb
+++ b/app/views/admin/seminars/_seminar_signup_render_table.html.erb
@@ -142,7 +142,7 @@
             <% end %>
           </tr>
         <% end %>
-        <% if @include_blank && @seminar_signups.count == 0 %>
+        <% if @include_blank %>
           <tr class="blank_tr">
             <% if @drag %>
               <td rowspan="3"></td>
diff --git a/app/views/admin/seminars/_seminar_signup_session_dashboard.html.erb b/app/views/admin/seminars/_seminar_signup_session_dashboard.html.erb
index af6f463..1327ba4 100644
--- a/app/views/admin/seminars/_seminar_signup_session_dashboard.html.erb
+++ b/app/views/admin/seminars/_seminar_signup_session_dashboard.html.erb
@@ -2,7 +2,7 @@
 <div style="clear: both;"></div>
 <% org_seminar_signups = @seminar_signups %>
 <% session_translation = (@seminar.seminar_submission_field_sets.select{|v| v.field_name=='description'}[0]['name'][I18n.locale] rescue "Session") %>
-<div style="float: left;width: 50%;">
+<div style="float: left;width: 50%;" class="left_block">
   <h4><%= session_translation %></h4>
   <% session_show_ids = @seminar.session_show_ids %>
   <% if session_show_ids.nil?
@@ -66,6 +66,22 @@
         </div>
     </div>
     <script type="text/javascript">
+      function add_obj(obj1,obj2){
+        var keys = Object.keys(obj1);
+        var obj = {};
+        keys.forEach(function(k){
+          obj[k] = obj1[k] + obj2[k];
+        });
+        return obj;
+      }
+      function sub_obj(obj1,obj2){
+        var keys = Object.keys(obj1);
+        var obj = {};
+        keys.forEach(function(k){
+          obj[k] = obj1[k] - obj2[k];
+        });
+        return obj;
+      }
       function generate_pagination(session_id,index=1,start=1,end=1,active=1){
         var pagination = $('<div class="pagination pagination-centered">');
         pagination.append('<div class="pagination"><ul></ul></div>');
@@ -155,10 +171,43 @@
           handle: ".brand",
           connectWith: ".table tbody",
           start: function(event, ui){
+            var target = $(event.target);
+            if(target.find("tr[data-id]").length <= 1){
+              target.find(".blank_tr").css("display","");
+            }else{
+              target.find(".blank_tr").css("display","none");
+            }
             $(".session_block").css("overflow","hidden");
+            parent_left_block = ui.item.parents(".left_block");
+            if(parent_left_block.length != 0){
+              var parent_block = ui.item.parents(".session_block");
+              parent_left_block.before(ui.item);
+              window.parent_block = parent_block;
+              ui.item.css("background","#ffffff");
+              window.over_flag = false;
+            }else{
+              window.parent_block = undefined;
+            }
+          },
+          sort: function(event, ui) {
+            if(window.parent_block != undefined){
+              var offset = ui.position;
+              var parent_offset = window.parent_block.offset();
+              if(!window.over_flag){
+                offset = add_obj(ui.position,parent_offset);
+                ui.item.offset(offset);
+              }
+            }
+          },
+          over: function( event, ui ) {
+            if(window.parent_block != undefined && $(this).data("id") != window.parent_block.data("id")){
+              window.over_flag = true;
+            }
           },
           stop: function(event, ui){
             $(".session_block").css("overflow","");
+            ui.item.css("background","");
+            console.log("stop")
           },
           update: function(event, ui) {
             var target = $(event.target);
@@ -184,7 +233,11 @@
         });
       }
       $(document).ready(function(){
-        
+        $("tbody").each(function(i,v){
+          if($(v).find("tr[data-id]").length != 0){
+            $(v).find("tr.blank_tr").css("display","none");
+          }
+        })
         init_func();
       })
       $(window).resize(function(){
diff --git a/app/views/admin/seminars/seminar_signup.html.erb b/app/views/admin/seminars/seminar_signup.html.erb
index 66b6ab8..439114a 100644
--- a/app/views/admin/seminars/seminar_signup.html.erb
+++ b/app/views/admin/seminars/seminar_signup.html.erb
@@ -3,8 +3,11 @@
   if(document.querySelectorAll("#orbit-bar").length==0) location.reload();
 </script>
 <% if @can_edit %>
+    <% if params[:type].blank?%>
+        <label><input id="copy_mode_on" type="checkbox"><%=t("seminar.copy_mode_on")%></label>
+    <% end %>
     <ul class="pull-right">
-        <li><a href="?type=" class="btn <%='active' if params[:type] == ''%>"><%= t('seminar.dashboard') %></a></li>
+        <li><a href="?type=" class="btn <%='active' if params[:type].blank? %>"><%= t('seminar.dashboard') %></a></li>
         <% if @seminar.enable_summary_choice %>
             <li><a href="?type=session" class="btn <%='active' if params[:type] == 'session'%>"><%= t('seminar.session_dashboard') %></a></li>
         <% end %>
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 2117db9..c24a376 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -20,6 +20,7 @@ en:
       verification_failed: Verification Failed #驗證碼錯誤
 
   seminar:
+    copy_mode_on: Copy mode on
     clone_signups: Clone Signups
     copy: Copy
     select_session: Select %{session}
diff --git a/config/locales/zh_tw.yml b/config/locales/zh_tw.yml
index 154d736..1f63e25 100644
--- a/config/locales/zh_tw.yml
+++ b/config/locales/zh_tw.yml
@@ -20,6 +20,7 @@ zh_tw:
       verification_failed: 驗證碼錯誤
 
   seminar:
+    copy_mode_on: 啟用複製模式
     clone_signups: 複製報名人
     copy: 複製
     select_session: 選擇%{session}