diff --git a/app/controllers/studien_controller.rb b/app/controllers/studien_controller.rb
index 3919265..f07e443 100755
--- a/app/controllers/studien_controller.rb
+++ b/app/controllers/studien_controller.rb
@@ -52,7 +52,7 @@ class StudienController < ApplicationController
 
   def create
     @studium = Studium.new(params[:studium])
-    Semester.batch_add @studium.name, @studium.typ, @studium.semester
+    @studium.batch_add_semester
     respond_to do |format|
       if @studium.save
         format.html { redirect_to url_for(@studium), notice: 'Studium was successfully created.' }
@@ -65,7 +65,7 @@ class StudienController < ApplicationController
 
   def update
     @studium = Studium.find(params[:id])
-    
+
     if @studium.update_attributes(params[:studium])
       redirect_to url_for(@studium), notice: 'Studium was successfully updated.' 
     else
diff --git a/app/models/semester.rb b/app/models/semester.rb
index 7771004..913a370 100755
--- a/app/models/semester.rb
+++ b/app/models/semester.rb
@@ -18,37 +18,4 @@ class Semester < ActiveRecord::Base
   belongs_to :studium, :foreign_key => "studium_id"
   validates :name, :presence => true
   validates :nummer, :presence => true
-  class << self
-    def batch_add(name, type, target)
-      if type == "Bachelor"
-        length = 6
-      else
-        length = 4
-      end
-      for i in 1..length
-        semester =Semester.new()
-        semester.name = i.to_s + ". " + name
-        semester.nummer = i
-        if i % 2 == 0
-          semester.ssws = "SS"
-        else
-          semester.ssws = "WS"
-        end
-        semester.save
-        target << semester
-      end
-      semester = Semester.new()
-      semester.name = "Ohne Zuordnung"
-      semester.nummer = 0
-      semester.ssws = "WS"
-      semester.save
-      target << semester
-    end
-
-    def batch_destroy(studium)
-      for m in studium.semester
-        m.destroy
-      end
-    end
-  end
 end
diff --git a/app/models/studium.rb b/app/models/studium.rb
index d48bda5..a072ced 100755
--- a/app/models/studium.rb
+++ b/app/models/studium.rb
@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 # == Schema Information
 #
 # Table name: studien
@@ -10,8 +11,6 @@
 #  typ        :string(255)
 #  created_at :datetime         not null
 #  updated_at :datetime         not null
-#
-
 class Studium < ActiveRecord::Base
   attr_accessible :desc, :name, :typ, :zahl
   has_many :modulgruppen, inverse_of: :studium, :class_name => "Modulgruppe"
@@ -19,6 +18,29 @@ class Studium < ActiveRecord::Base
   
   validates :typ, :inclusion => {:in => ["Bachelor","Master"] }
   validates :name, :uniqueness => true, :presence=>true
-  validates :zahl, :uniqueness => true, :presence=>true
+  validates :zahl, :format=>{:with=>/^0(33|66)[0-9]{3}$/}, :uniqueness => true 
   translates :desc,:shortdesc, :versioning =>true,:fallbacks_for_empty_translations => true
+  
+  def batch_add_semester
+    # Semester automatisch zu Studien hinzufügen
+    if self.typ == "Bachelor"
+      length = 6
+    else
+      length = 4
+    end
+    for i in 1..length
+      semester =Semester.new()
+      semester.name = i.to_s + '. ' + self.name
+      semester.nummer = i
+      semester.ssws = ((i % 2 == 0) ? "SS" : "WS")
+      semester.save
+      self.semester << semester
+    end
+    semester = Semester.new()
+    semester.name = 'Ohne Zuordnung (' + self.name + ')'
+    semester.nummer = 0
+    semester.ssws = "WS"
+    semester.save
+    self.semester << semester
+  end
 end
diff --git a/app/views/studien/_navigation.html.erb b/app/views/studien/_navigation.html.erb
index fce00a2..675da8f 100755
--- a/app/views/studien/_navigation.html.erb
+++ b/app/views/studien/_navigation.html.erb
@@ -1,10 +1,20 @@
-<%= link_to '<i class="icon-list"></i>'.html_safe+ I18n.t("studien.allestudien"), studien_path,:raw=>true %> / 
-<% Studium.all.each do |s| %>
-  <% if @sem=='true' %>
-    <%= link_to s.name + " / ", studium_semesteransicht_path(s) %>
-  <% else %>
-    <%= link_to s.name + " / ", studium_path(s) %>
-  <% end %>
-<% end %>
 
-<%= link_to  @text, @path%>
+<ul class="breadcrumb">
+<li>  <%= link_to '<i class="icon-list"></i>'.html_safe+ I18n.t("studien.allestudien"), studien_path,:raw=>true %>
+      <span class="divider">/</span></li>
+<li> <%= link_to  @text, @path%>
+      <span class="divider">/</span></li>
+<br>
+  <% Studium.all.each do |s| %>
+    <li>
+      <% if @sem=='true' %>
+	<%= link_to s.name, studium_semesteransicht_path(s) %>
+      <% else %>
+	<%= link_to s.name, studium_path(s) %>
+      <% end %>
+      <span class="divider">/</span></li>
+    </li>
+  <% end %>
+
+</ul>
+
diff --git a/app/views/studien/semesteransicht.html.erb b/app/views/studien/semesteransicht.html.erb
index cc00404..de3a868 100644
--- a/app/views/studien/semesteransicht.html.erb
+++ b/app/views/studien/semesteransicht.html.erb
@@ -1,21 +1,15 @@
 <%= render :partial=>'studien/navigation'%>
-<div>
-  <h1><%= @studium.typ %> <%= @studium.name %>  (<%= @studium.zahl %>)</h1>
-  <%= raw(@studium.desc) %>
-  <% @studium.semester.each do |sem| %>
-    <div class="row-fluid">
-      <% if sem.nummer > 0 %>
-	<h2><%= sem.nummer.to_s + ". Semester" %></h2>
-      <% else %>
-	<h2> Ohne Zuordnung </h2>
-      <% end %>
-      <div class="span<%= sem[:width]%> min-width:13em;">
-	<ul>      
-	  <% sem.lvas.sort_by{|n| n[:name]}.each do |l| %>
-	    <li><%= render :partial=>'lvas/lva_semester', :locals =>{:lva => l}%>
-	      <%end%>
-	</ul>
-      </div>
-      <% end %>
+
+<h1><%= @studium.typ %> <%= @studium.name %>  (<%= @studium.zahl %>)</h1>
+<%= raw(@studium.desc) %>
+<% @studium.semester.each do |sem| %>
+  <div class="row-fluid">
+    <h2><%= sem.name %></h2>
+    <div class="span<%= sem[:width]%> min-width:13em;">
+      <ul>      
+	<% sem.lvas.sort_by{|n| n[:name]}.each do |l| %>
+	  <li><%= render :partial=>'lvas/lva_semester', :locals =>{:lva => l}%>
+	<% end %>
+      </ul>
     </div>
-</div>
+<% end %>