diff --git a/Frontend/export/elog.csv b/Frontend/export/elog.csv
index 9e9b0e81c09b31b796a037debe276ae307f41986..d1837965b700e593f3577cf2f211b88d6034186e 100644
--- a/Frontend/export/elog.csv
+++ b/Frontend/export/elog.csv
@@ -1,40 +1,24 @@
 CaseID,Activity,StartTimestamp,EndTimestamp
-0,place order,0.0,2.0
-1,place order,2.0,4.0
-2,place order,4.0,6.0
-0,arrange standard order,6.0,18.0
-1,arrange standard order,6.0,17.0
-2,arrange custom order,6.0,34.0
-3,place order,13.0,15.0
-3,arrange custom order,15.0,43.0
-1,pick from stock C,17.0,47.0
-0,pick from stock A,18.0,48.0
-4,place order,24.0,26.0
-4,arrange custom order,26.0,53.0
-2,manufacture A,34.0,
-5,place order,37.0,39.0
-5,arrange custom order,39.0,59.0
-3,manufacture B,43.0,
-1,pack A,47.0,64.0
-0,pack A,48.0,64.0
-6,place order,52.0,54.0
-4,manufacture A,54.0,
-6,arrange standard order,54.0,64.0
-5,manufacture B,59.0,
-1,attempt delivery B,64.0,
-0,attempt delivery B,64.0,
-6,pick from stock A,64.0,77.0
-7,place order,66.0,68.0
-7,arrange custom order,68.0,89.0
-8,place order,77.0,79.0
-6,pack B,79.0,98.0
-8,arrange custom order,79.0,99.0
-9,place order,89.0,91.0
-7,manufacture B,91.0,
-9,arrange custom order,91.0,
-6,attempt delivery A,98.0,
-8,manufacture A,99.0,
-10,place order,104.0,106.0
-10,arrange custom order,106.0,
-11,place order,115.0,117.0
-11,arrange standard order,117.0,
+0,place order,2023-07-07 16:41,2023-07-07 16:43
+1,place order,2023-07-07 16:43,2023-07-07 16:43
+2,place order,2023-07-07 16:45,2023-07-07 16:43
+0,arrange custom order,2023-07-07 16:47,2023-07-07 17:08
+1,arrange custom order,2023-07-07 16:47,2023-07-07 17:04
+2,arrange custom order,2023-07-07 16:47,2023-07-07 17:02
+3,place order,2023-07-07 16:54,2023-07-07 16:43
+3,arrange custom order,2023-07-07 16:56,2023-07-07 17:10
+4,place order,2023-07-07 17:04,2023-07-07 16:43
+2,manufacture B,2023-07-07 17:08, 
+4,arrange standard order,2023-07-07 17:08,2023-07-07 16:54
+1,manufacture B,2023-07-07 17:10, 
+0,manufacture A,2023-07-07 17:14, 
+5,place order,2023-07-07 17:18,2023-07-07 16:43
+5,arrange standard order,2023-07-07 17:20,2023-07-07 16:51
+4,pick from stock C,2023-07-07 17:21, 
+3,manufacture B,2023-07-07 17:25, 
+6,place order,2023-07-07 17:30,2023-07-07 16:43
+5,pick from stock A,2023-07-07 17:32,2023-07-07 16:57
+6,arrange custom order,2023-07-07 17:32, 
+7,place order,2023-07-07 17:41,2023-07-07 16:43
+7,arrange standard order,2023-07-07 17:43, 
+5,pack C,2023-07-07 17:48, 
diff --git a/Frontend/export/elog.xes b/Frontend/export/elog.xes
index 527a4928d6eb6ab72fca7cbb844880e1ff186911..f5392211ec31c1a88fd746b492ce7f2506656e80 100644
--- a/Frontend/export/elog.xes
+++ b/Frontend/export/elog.xes
@@ -3,301 +3,185 @@
 	<trace>
 		<event>
 			<string key="Activity" value="place order" />
-			<float key="StartTimestamp" value="0.0" />
-			<int key="EndTimestamp" value="2" />
+			<string key="StartTimestamp" value="2023-07-07 16:41" />
+			<string key="EndTimestamp" value="2023-07-07 16:43" />
 			<int key="CaseID" value="0" />
 		</event>
 	</trace>
 	<trace>
 		<event>
 			<string key="Activity" value="place order" />
-			<float key="StartTimestamp" value="2.0" />
-			<int key="EndTimestamp" value="4" />
+			<string key="StartTimestamp" value="2023-07-07 16:43" />
+			<string key="EndTimestamp" value="2023-07-07 16:43" />
 			<int key="CaseID" value="1" />
 		</event>
 	</trace>
 	<trace>
 		<event>
 			<string key="Activity" value="place order" />
-			<float key="StartTimestamp" value="4.0" />
-			<int key="EndTimestamp" value="6" />
+			<string key="StartTimestamp" value="2023-07-07 16:45" />
+			<string key="EndTimestamp" value="2023-07-07 16:43" />
 			<int key="CaseID" value="2" />
 		</event>
 	</trace>
 	<trace>
 		<event>
-			<string key="Activity" value="arrange standard order" />
-			<float key="StartTimestamp" value="6.0" />
-			<int key="EndTimestamp" value="18" />
+			<string key="Activity" value="arrange custom order" />
+			<string key="StartTimestamp" value="2023-07-07 16:47" />
+			<string key="EndTimestamp" value="2023-07-07 17:08" />
 			<int key="CaseID" value="0" />
 		</event>
 	</trace>
 	<trace>
 		<event>
-			<string key="Activity" value="arrange standard order" />
-			<float key="StartTimestamp" value="6.0" />
-			<int key="EndTimestamp" value="17" />
+			<string key="Activity" value="arrange custom order" />
+			<string key="StartTimestamp" value="2023-07-07 16:47" />
+			<string key="EndTimestamp" value="2023-07-07 17:04" />
 			<int key="CaseID" value="1" />
 		</event>
 	</trace>
 	<trace>
 		<event>
 			<string key="Activity" value="arrange custom order" />
-			<float key="StartTimestamp" value="6.0" />
-			<int key="EndTimestamp" value="34" />
+			<string key="StartTimestamp" value="2023-07-07 16:47" />
+			<string key="EndTimestamp" value="2023-07-07 17:02" />
 			<int key="CaseID" value="2" />
 		</event>
 	</trace>
 	<trace>
 		<event>
 			<string key="Activity" value="place order" />
-			<float key="StartTimestamp" value="13.0" />
-			<int key="EndTimestamp" value="15" />
+			<string key="StartTimestamp" value="2023-07-07 16:54" />
+			<string key="EndTimestamp" value="2023-07-07 16:43" />
 			<int key="CaseID" value="3" />
 		</event>
 	</trace>
 	<trace>
 		<event>
 			<string key="Activity" value="arrange custom order" />
-			<float key="StartTimestamp" value="15.0" />
-			<int key="EndTimestamp" value="43" />
+			<string key="StartTimestamp" value="2023-07-07 16:56" />
+			<string key="EndTimestamp" value="2023-07-07 17:10" />
 			<int key="CaseID" value="3" />
 		</event>
 	</trace>
-	<trace>
-		<event>
-			<string key="Activity" value="pick from stock C" />
-			<float key="StartTimestamp" value="17.0" />
-			<int key="EndTimestamp" value="47" />
-			<int key="CaseID" value="1" />
-		</event>
-	</trace>
-	<trace>
-		<event>
-			<string key="Activity" value="pick from stock A" />
-			<float key="StartTimestamp" value="18.0" />
-			<int key="EndTimestamp" value="48" />
-			<int key="CaseID" value="0" />
-		</event>
-	</trace>
 	<trace>
 		<event>
 			<string key="Activity" value="place order" />
-			<float key="StartTimestamp" value="24.0" />
-			<int key="EndTimestamp" value="26" />
-			<int key="CaseID" value="4" />
-		</event>
-	</trace>
-	<trace>
-		<event>
-			<string key="Activity" value="arrange custom order" />
-			<float key="StartTimestamp" value="26.0" />
-			<int key="EndTimestamp" value="53" />
+			<string key="StartTimestamp" value="2023-07-07 17:04" />
+			<string key="EndTimestamp" value="2023-07-07 16:43" />
 			<int key="CaseID" value="4" />
 		</event>
 	</trace>
 	<trace>
 		<event>
-			<string key="Activity" value="manufacture A" />
-			<float key="StartTimestamp" value="34.0" />
+			<string key="Activity" value="manufacture B" />
+			<string key="StartTimestamp" value="2023-07-07 17:08" />
+			<string key="EndTimestamp" value=" " />
 			<int key="CaseID" value="2" />
 		</event>
 	</trace>
 	<trace>
 		<event>
-			<string key="Activity" value="place order" />
-			<float key="StartTimestamp" value="37.0" />
-			<int key="EndTimestamp" value="39" />
-			<int key="CaseID" value="5" />
-		</event>
-	</trace>
-	<trace>
-		<event>
-			<string key="Activity" value="arrange custom order" />
-			<float key="StartTimestamp" value="39.0" />
-			<int key="EndTimestamp" value="59" />
-			<int key="CaseID" value="5" />
+			<string key="Activity" value="arrange standard order" />
+			<string key="StartTimestamp" value="2023-07-07 17:08" />
+			<string key="EndTimestamp" value="2023-07-07 16:54" />
+			<int key="CaseID" value="4" />
 		</event>
 	</trace>
 	<trace>
 		<event>
 			<string key="Activity" value="manufacture B" />
-			<float key="StartTimestamp" value="43.0" />
-			<int key="CaseID" value="3" />
-		</event>
-	</trace>
-	<trace>
-		<event>
-			<string key="Activity" value="pack A" />
-			<float key="StartTimestamp" value="47.0" />
-			<int key="EndTimestamp" value="64" />
+			<string key="StartTimestamp" value="2023-07-07 17:10" />
+			<string key="EndTimestamp" value=" " />
 			<int key="CaseID" value="1" />
 		</event>
 	</trace>
 	<trace>
 		<event>
-			<string key="Activity" value="pack A" />
-			<float key="StartTimestamp" value="48.0" />
-			<int key="EndTimestamp" value="64" />
+			<string key="Activity" value="manufacture A" />
+			<string key="StartTimestamp" value="2023-07-07 17:14" />
+			<string key="EndTimestamp" value=" " />
 			<int key="CaseID" value="0" />
 		</event>
 	</trace>
 	<trace>
 		<event>
 			<string key="Activity" value="place order" />
-			<float key="StartTimestamp" value="52.0" />
-			<int key="EndTimestamp" value="54" />
-			<int key="CaseID" value="6" />
-		</event>
-	</trace>
-	<trace>
-		<event>
-			<string key="Activity" value="manufacture A" />
-			<float key="StartTimestamp" value="54.0" />
-			<int key="CaseID" value="4" />
+			<string key="StartTimestamp" value="2023-07-07 17:18" />
+			<string key="EndTimestamp" value="2023-07-07 16:43" />
+			<int key="CaseID" value="5" />
 		</event>
 	</trace>
 	<trace>
 		<event>
 			<string key="Activity" value="arrange standard order" />
-			<float key="StartTimestamp" value="54.0" />
-			<int key="EndTimestamp" value="64" />
-			<int key="CaseID" value="6" />
-		</event>
-	</trace>
-	<trace>
-		<event>
-			<string key="Activity" value="manufacture B" />
-			<float key="StartTimestamp" value="59.0" />
+			<string key="StartTimestamp" value="2023-07-07 17:20" />
+			<string key="EndTimestamp" value="2023-07-07 16:51" />
 			<int key="CaseID" value="5" />
 		</event>
 	</trace>
 	<trace>
 		<event>
-			<string key="Activity" value="attempt delivery B" />
-			<float key="StartTimestamp" value="64.0" />
-			<int key="CaseID" value="1" />
-		</event>
-	</trace>
-	<trace>
-		<event>
-			<string key="Activity" value="attempt delivery B" />
-			<float key="StartTimestamp" value="64.0" />
-			<int key="CaseID" value="0" />
-		</event>
-	</trace>
-	<trace>
-		<event>
-			<string key="Activity" value="pick from stock A" />
-			<float key="StartTimestamp" value="64.0" />
-			<int key="EndTimestamp" value="77" />
-			<int key="CaseID" value="6" />
-		</event>
-	</trace>
-	<trace>
-		<event>
-			<string key="Activity" value="place order" />
-			<float key="StartTimestamp" value="66.0" />
-			<int key="EndTimestamp" value="68" />
-			<int key="CaseID" value="7" />
+			<string key="Activity" value="pick from stock C" />
+			<string key="StartTimestamp" value="2023-07-07 17:21" />
+			<string key="EndTimestamp" value=" " />
+			<int key="CaseID" value="4" />
 		</event>
 	</trace>
 	<trace>
 		<event>
-			<string key="Activity" value="arrange custom order" />
-			<float key="StartTimestamp" value="68.0" />
-			<int key="EndTimestamp" value="89" />
-			<int key="CaseID" value="7" />
+			<string key="Activity" value="manufacture B" />
+			<string key="StartTimestamp" value="2023-07-07 17:25" />
+			<string key="EndTimestamp" value=" " />
+			<int key="CaseID" value="3" />
 		</event>
 	</trace>
 	<trace>
 		<event>
 			<string key="Activity" value="place order" />
-			<float key="StartTimestamp" value="77.0" />
-			<int key="EndTimestamp" value="79" />
-			<int key="CaseID" value="8" />
-		</event>
-	</trace>
-	<trace>
-		<event>
-			<string key="Activity" value="pack B" />
-			<float key="StartTimestamp" value="79.0" />
-			<int key="EndTimestamp" value="98" />
+			<string key="StartTimestamp" value="2023-07-07 17:30" />
+			<string key="EndTimestamp" value="2023-07-07 16:43" />
 			<int key="CaseID" value="6" />
 		</event>
 	</trace>
 	<trace>
 		<event>
-			<string key="Activity" value="arrange custom order" />
-			<float key="StartTimestamp" value="79.0" />
-			<int key="EndTimestamp" value="99" />
-			<int key="CaseID" value="8" />
-		</event>
-	</trace>
-	<trace>
-		<event>
-			<string key="Activity" value="place order" />
-			<float key="StartTimestamp" value="89.0" />
-			<int key="EndTimestamp" value="91" />
-			<int key="CaseID" value="9" />
-		</event>
-	</trace>
-	<trace>
-		<event>
-			<string key="Activity" value="manufacture B" />
-			<float key="StartTimestamp" value="91.0" />
-			<int key="CaseID" value="7" />
+			<string key="Activity" value="pick from stock A" />
+			<string key="StartTimestamp" value="2023-07-07 17:32" />
+			<string key="EndTimestamp" value="2023-07-07 16:57" />
+			<int key="CaseID" value="5" />
 		</event>
 	</trace>
 	<trace>
 		<event>
 			<string key="Activity" value="arrange custom order" />
-			<float key="StartTimestamp" value="91.0" />
-			<int key="CaseID" value="9" />
-		</event>
-	</trace>
-	<trace>
-		<event>
-			<string key="Activity" value="attempt delivery A" />
-			<float key="StartTimestamp" value="98.0" />
+			<string key="StartTimestamp" value="2023-07-07 17:32" />
+			<string key="EndTimestamp" value=" " />
 			<int key="CaseID" value="6" />
 		</event>
 	</trace>
-	<trace>
-		<event>
-			<string key="Activity" value="manufacture A" />
-			<float key="StartTimestamp" value="99.0" />
-			<int key="CaseID" value="8" />
-		</event>
-	</trace>
 	<trace>
 		<event>
 			<string key="Activity" value="place order" />
-			<float key="StartTimestamp" value="104.0" />
-			<int key="EndTimestamp" value="106" />
-			<int key="CaseID" value="10" />
-		</event>
-	</trace>
-	<trace>
-		<event>
-			<string key="Activity" value="arrange custom order" />
-			<float key="StartTimestamp" value="106.0" />
-			<int key="CaseID" value="10" />
+			<string key="StartTimestamp" value="2023-07-07 17:41" />
+			<string key="EndTimestamp" value="2023-07-07 16:43" />
+			<int key="CaseID" value="7" />
 		</event>
 	</trace>
 	<trace>
 		<event>
-			<string key="Activity" value="place order" />
-			<float key="StartTimestamp" value="115.0" />
-			<int key="EndTimestamp" value="117" />
-			<int key="CaseID" value="11" />
+			<string key="Activity" value="arrange standard order" />
+			<string key="StartTimestamp" value="2023-07-07 17:43" />
+			<string key="EndTimestamp" value=" " />
+			<int key="CaseID" value="7" />
 		</event>
 	</trace>
 	<trace>
 		<event>
-			<string key="Activity" value="arrange standard order" />
-			<float key="StartTimestamp" value="117.0" />
-			<int key="CaseID" value="11" />
+			<string key="Activity" value="pack C" />
+			<string key="StartTimestamp" value="2023-07-07 17:48" />
+			<string key="EndTimestamp" value=" " />
+			<int key="CaseID" value="5" />
 		</event>
 	</trace>
 </log>
diff --git a/Frontend/main.py b/Frontend/main.py
index 19ddaa6ee7021bf959cc228e69dac84a3b322826..84103775f4f7d0429e659a09a9619128a861018f 100644
--- a/Frontend/main.py
+++ b/Frontend/main.py
@@ -62,7 +62,6 @@ def upload_file():
         flash('No files selected! Please select a file!')
         return redirect(url_for('index'))
 
-    print(uploaded_file.filename)
     return redirect(url_for('case_id', filename = uploaded_file.filename)) 
     
 """
@@ -114,7 +113,7 @@ def case_id(filename):
         for file in os.listdir('static/'):
             if file.startswith('preview_net'):  # not to remove other images
                 os.remove('static/' + file)
-                
+
         result = int(previewid)
 
         petrinet.decorate_petri_net(result, filename)
diff --git a/Frontend/static/net.png b/Frontend/static/net.png
index 47374c3b39d077726a86c86caabe3849804176e9..48f3ad6198131b342e3deb8aa4e14f2ecbf7d60a 100644
Binary files a/Frontend/static/net.png and b/Frontend/static/net.png differ
diff --git a/Frontend/static/preview_net.png b/Frontend/static/preview_net.png
index e9e1ae8ef4d28370396c97f0fbaeaa900e606207..adbb778101183b46d13e9b84ad1fceb9ed8fc3c0 100644
Binary files a/Frontend/static/preview_net.png and b/Frontend/static/preview_net.png differ
diff --git a/Frontend/upload/elog (10).csv b/Frontend/upload/elog (10).csv
new file mode 100644
index 0000000000000000000000000000000000000000..1b119c821cfa7bcf4cd9a31bd692a1a87533af2e
--- /dev/null
+++ b/Frontend/upload/elog (10).csv	
@@ -0,0 +1,22 @@
+CaseID,Activity,StartTimestamp,EndTimestamp
+0,place order,2023-07-07 16:41,2023-07-07 16:43
+1,place order,2023-07-07 16:43,2023-07-07 16:43
+2,place order,2023-07-07 16:45,2023-07-07 16:43
+0,arrange custom order,2023-07-07 16:47,2023-07-07 17:02
+1,arrange custom order,2023-07-07 16:47,2023-07-07 17:03
+2,arrange custom order,2023-07-07 16:47,2023-07-07 17:04
+3,place order,2023-07-07 16:54,2023-07-07 16:43
+3,arrange custom order,2023-07-07 16:56,2023-07-07 17:11
+4,place order,2023-07-07 17:07,2023-07-07 16:43
+0,manufacture B,2023-07-07 17:09, 
+1,manufacture B,2023-07-07 17:09, 
+4,arrange custom order,2023-07-07 17:09,2023-07-07 17:11
+2,manufacture B,2023-07-07 17:10, 
+5,place order,2023-07-07 17:20,2023-07-07 16:43
+5,arrange custom order,2023-07-07 17:22,2023-07-07 17:01
+3,manufacture B,2023-07-07 17:26, 
+6,place order,2023-07-07 17:34,2023-07-07 16:43
+6,arrange custom order,2023-07-07 17:36, 
+4,manufacture B,2023-07-07 17:39, 
+5,manufacture B,2023-07-07 17:42, 
+7,place order,2023-07-07 17:47, 
diff --git a/Frontend/upload/elog (9).csv b/Frontend/upload/elog (9).csv
new file mode 100644
index 0000000000000000000000000000000000000000..f7a6a6f17cc433ec98837ec56586cabd067975f2
--- /dev/null
+++ b/Frontend/upload/elog (9).csv	
@@ -0,0 +1,9 @@
+CaseID,Activity,StartTimestamp,EndTimestamp
+0,place order,2023-07-07 17:28,2023-07-07 17:30
+1,place order,2023-07-07 17:30,2023-07-07 17:30
+2,place order,2023-07-07 17:32,2023-07-07 17:30
+0,arrange custom order,2023-07-07 17:34,
+1,arrange custom order,2023-07-07 17:34,
+2,arrange custom order,2023-07-07 17:34,
+3,place order,2023-07-07 17:38,2023-07-07 17:30
+3,arrange custom order,2023-07-07 17:40,
diff --git a/backend/__pycache__/eventlog.cpython-311.pyc b/backend/__pycache__/eventlog.cpython-311.pyc
index d23f62934404a8db52bb3bba4747d3ac032974a5..b01a5e7294cb4d2e0635882277acb4c49dc6091e 100644
Binary files a/backend/__pycache__/eventlog.cpython-311.pyc and b/backend/__pycache__/eventlog.cpython-311.pyc differ
diff --git a/backend/__pycache__/simplesimmodel.cpython-311.pyc b/backend/__pycache__/simplesimmodel.cpython-311.pyc
index fdc763fd02a7702af9867c104369289548f43dac..ebc60eb64288c41e6615808803a79c5a522b4589 100644
Binary files a/backend/__pycache__/simplesimmodel.cpython-311.pyc and b/backend/__pycache__/simplesimmodel.cpython-311.pyc differ
diff --git a/backend/eventlog.py b/backend/eventlog.py
index 99cd63e9b7307426803ebada0afa85db6f49c5fc..b08f5c5aed7aaa43e07abba24a1c348eccbf1522 100644
--- a/backend/eventlog.py
+++ b/backend/eventlog.py
@@ -24,12 +24,13 @@ from pm4py.objects.log.obj import Event
 from pm4py.objects.log.exporter.xes import exporter as xes_exporter
 from pm4py.objects.log.importer.xes import importer as xes_importer
 import os
+import datetime
 
 import simplesimmodel as model
 from businessprocess import BusinessProcess
 
 
-def add_start_event(process, event_id, case_id, activity, start_timestamp):
+def add_start_event(process, event_id, case_id, activity, start):
     """Add the start of an event to the event log of a process.
 
     Parameters
@@ -40,30 +41,35 @@ def add_start_event(process, event_id, case_id, activity, start_timestamp):
         the unique case-id of a case 
     activity : str
         the name of the activity
-    start_timestamp : float
+    start : float
         the relative start time of the event
     """
+
+    start_timestamp = current_time + datetime.timedelta(minutes = start)
+
     process.event_log.append(event_id)
     process.event_log[event_id] = {
         'CaseID': case_id,
         'Activity': activity,
-        'StartTimestamp': float(start_timestamp),
-        'EndTimestamp': None
+        'StartTimestamp': start_timestamp.strftime('%Y-%m-%d %H:%M'),
+        'EndTimestamp': " "
     }
     process.event_counter += 1
 
-def add_end_event(process, event_id, end_timestamp):
+def add_end_event(process, event_id, duration):
     """Add the end of an event to the event log of a process.
 
     Parameters
     ----------
     event_id : int
         the unique id of the event 
-    end_timestamp : float
-        the relative end time of the event
+    duartion : float
+        the complete duration of the event
     """
+
     event = process.event_log[event_id]
-    event['EndTimestamp'] = end_timestamp
+    end_timestamp = current_time + datetime.timedelta(minutes = duration)
+    event['EndTimestamp'] = end_timestamp.strftime('%Y-%m-%d %H:%M')
 
 def export_to_csv(process, file_path):
     """Export the event log of a process simulation to .csv.
@@ -134,9 +140,7 @@ def convert_to_dataframe(name):
     
     # file_path = r"Frontend/upload/" + name #docker
     file_path = r"upload/" + name 
-    print(name)
     file_extension = os.path.splitext(file_path)[1].lower()
-    print(file_extension)
     
     if file_extension == '.csv':
         event_log_df = pd.read_csv(file_path)
@@ -154,6 +158,7 @@ def convert_to_dataframe(name):
         event_log_df = pd.DataFrame(event_data)
     else:
         print(f"Unsupported file type: {file_extension}")
+        return None
 
     # print(event_log_df)
     return event_log_df
@@ -193,12 +198,24 @@ def format_check(name):
         if activity not in allowed_activities:
             return False
         
+        res = True
+
         start = event['StartTimestamp']
-        if not isinstance(start, float):
+        print(start)
+        try:
+            bool(datetime.datetime.strptime(start, '%Y-%m-%d %H:%M'))
+        except ValueError:
+            res = False
+        if not res and not (start == " " or start == None):
             return False
         
         end = event['EndTimestamp']
-        if not isinstance(end, float):
+        print(end)
+        try:
+            bool(datetime.datetime.strptime(end, '%Y-%m-%d %H:%M'))
+        except ValueError:
+            res = False
+        if not res and not (end == " " or end == None):
             return False
         
     return True
@@ -404,6 +421,8 @@ def generate_event_log(time):
     env = simpy.Environment()
     business_process = BusinessProcess(env, ressources)
     business_process.event_log_flag = True
+    global current_time
+    current_time = datetime.datetime.now() - datetime.timedelta(minutes = time)
     env.process(model.run_process(env, business_process))
     env.run(until = time)
     # export to both formats
diff --git a/backend/simplesimmodel.py b/backend/simplesimmodel.py
index 640160ff4b2edef990215ef3423da757edc881c4..f721c518b6bfb0fc2913ee16ab75e4435bb2649a 100644
--- a/backend/simplesimmodel.py
+++ b/backend/simplesimmodel.py
@@ -128,12 +128,14 @@ def execute_case(env, case, process):
         # if the event_log_flag is set add the event to the log
         if process.event_log_flag:
             event_counter = process.event_counter
-            log.add_start_event(process, event_counter, case, "place order", env.now)
+            start = env.now
+            log.add_start_event(process, event_counter, case, "place order", start)
 
         yield env.process(process.place_order()) # do the activity
 
         if process.event_log_flag: 
-            log.add_end_event(process, event_counter, env.now)
+            duration = env.now - start
+            log.add_end_event(process, event_counter, duration)
 
 
     # if the last action was made from the agent set the process flag to be able to return to the environment's step function
@@ -159,10 +161,12 @@ def execute_case(env, case, process):
             yield request
             if process.event_log_flag:
                 event_counter = process.event_counter
+                start = env.now
                 log.add_start_event(process, event_counter, case, "arrange standard order", env.now)
             yield env.process(process.arrange_standard_order())
             if process.event_log_flag: 
-                log.add_end_event(process, event_counter, env.now)
+                duration = env.now - start
+                log.add_end_event(process, event_counter, duration)
             if case_obj.agent: 
                 process.flag = False
             with process.system.request() as request:
@@ -176,10 +180,12 @@ def execute_case(env, case, process):
             yield request
             if process.event_log_flag:
                 event_counter = process.event_counter
+                start = env.now
                 log.add_start_event(process, event_counter, case, "arrange custom order", env.now)
             yield env.process(process.arrange_custom_order())
-            if process.event_log_flag: 
-                log.add_end_event(process, event_counter, env.now)
+            if process.event_log_flag:
+                duration = env.now - start 
+                log.add_end_event(process, event_counter, duration)
             if case_obj.agent: 
                 process.flag = False
             with process.system.request() as request:
@@ -206,10 +212,12 @@ def execute_case(env, case, process):
             yield request
             if process.event_log_flag:
                 event_counter = process.event_counter
+                start = env.now
                 log.add_start_event(process, event_counter, case, "pick from stock A", env.now)
             yield env.process(process.pick_from_stock_a())
             if process.event_log_flag: 
-                log.add_end_event(process, event_counter, env.now)
+                duration = env.now - start
+                log.add_end_event(process, event_counter, duration)
             if case_obj.agent: 
                 process.flag = False
             with process.system.request() as request:
@@ -221,10 +229,12 @@ def execute_case(env, case, process):
             yield request
             if process.event_log_flag:
                 event_counter = process.event_counter
+                start = env.now
                 log.add_start_event(process, event_counter, case, "pick from stock B", env.now)
             yield env.process(process.pick_from_stock_b())
             if process.event_log_flag: 
-                log.add_end_event(process, event_counter, env.now)
+                duration = env.now - start
+                log.add_end_event(process, event_counter, duration)
             if case_obj.agent: 
                 process.flag = False
             with process.system.request() as request:
@@ -236,10 +246,12 @@ def execute_case(env, case, process):
             yield request
             if process.event_log_flag:
                 event_counter = process.event_counter
+                start = env.now
                 log.add_start_event(process, event_counter, case, "pick from stock C", env.now)
             yield env.process(process.pick_from_stock_c())
             if process.event_log_flag: 
-                log.add_end_event(process, event_counter, env.now)
+                duration = env.now - start
+                log.add_end_event(process, event_counter, duration)
             if case_obj.agent: 
                 process.flag = False
             with process.system.request() as request:
@@ -251,10 +263,12 @@ def execute_case(env, case, process):
             yield request
             if process.event_log_flag:
                 event_counter = process.event_counter
+                start = env.now
                 log.add_start_event(process, event_counter, case, "manufacture A", env.now)
             yield env.process(process.manufacture_a())
             if process.event_log_flag: 
-                log.add_end_event(process, event_counter, env.now)
+                duration = env.now - start
+                log.add_end_event(process, event_counter, duration)
             if case_obj.agent: 
                 process.flag = False
             with process.system.request() as request:
@@ -266,10 +280,12 @@ def execute_case(env, case, process):
             yield request
             if process.event_log_flag:
                 event_counter = process.event_counter
+                start = env.now
                 log.add_start_event(process, event_counter, case, "manufacture B", env.now)
             yield env.process(process.manufacture_b())
             if process.event_log_flag: 
-                log.add_end_event(process, event_counter, env.now)
+                duration = env.now - start
+                log.add_end_event(process, event_counter, duration)
             if case_obj.agent: 
                 process.flag = False
             with process.system.request() as request:
@@ -287,10 +303,12 @@ def execute_case(env, case, process):
             yield request
             if process.event_log_flag:
                 event_counter = process.event_counter
+                start = env.now
                 log.add_start_event(process, event_counter, case, "pack A", env.now)
             yield env.process(process.pack_a())
             if process.event_log_flag: 
-                log.add_end_event(process, event_counter, env.now)
+                duration = env.now - start
+                log.add_end_event(process, event_counter, duration)
             if case_obj.agent: 
                 process.flag = False
             with process.system.request() as request:
@@ -302,10 +320,11 @@ def execute_case(env, case, process):
             yield request
             if process.event_log_flag:
                 event_counter = process.event_counter
+                start = env.now
                 log.add_start_event(process, event_counter, case, "pack B", env.now)
             yield env.process(process.pack_b())
             if process.event_log_flag: 
-                log.add_end_event(process, event_counter, env.now)
+                log.add_end_event(process, event_counter, duration)
             if case_obj.agent: 
                 process.flag = False
 
@@ -318,10 +337,12 @@ def execute_case(env, case, process):
             yield request
             if process.event_log_flag:
                 event_counter = process.event_counter
+                start = env.now
                 log.add_start_event(process, event_counter, case, "pack C", env.now)
             yield env.process(process.pack_c())
             if process.event_log_flag: 
-                log.add_end_event(process, event_counter, env.now)
+                duration = env.now - start
+                log.add_end_event(process, event_counter, duration)
             if case_obj.agent: 
                 process.flag = False
             with process.system.request() as request:
@@ -338,10 +359,12 @@ def execute_case(env, case, process):
             yield request
             if process.event_log_flag:
                 event_counter = process.event_counter
+                start = env.now
                 log.add_start_event(process, event_counter, case, "attempt delivery A", env.now)
             yield env.process(process.attempt_delivery_a())
             if process.event_log_flag: 
-                log.add_end_event(process, event_counter, env.now)
+                duration = env.now - start
+                log.add_end_event(process, event_counter, duration)
             if case_obj.agent: 
                 process.flag = False
             with process.system.request() as request:
@@ -353,10 +376,12 @@ def execute_case(env, case, process):
             yield request
             if process.event_log_flag:
                 event_counter = process.event_counter
+                start = env.now
                 log.add_start_event(process, event_counter, case, "attempt delivery B", env.now)
             yield env.process(process.attempt_delivery_b())
             if process.event_log_flag: 
-                log.add_end_event(process, event_counter, env.now)
+                duration = env.now - start
+                log.add_end_event(process, event_counter, duration)
             if case_obj.agent: 
                 process.flag = False
             with process.system.request() as request:
@@ -368,10 +393,12 @@ def execute_case(env, case, process):
             yield request
             if process.event_log_flag:
                 event_counter = process.event_counter
+                start = env.now
                 log.add_start_event(process, event_counter, case, "attempt delivery C", env.now)
             yield env.process(process.attempt_delivery_c())
             if process.event_log_flag: 
-                log.add_end_event(process, event_counter, env.now)
+                duration = env.now - start
+                log.add_end_event(process, event_counter, duration)
             if case_obj.agent: 
                 process.flag = False
             with process.system.request() as request:
@@ -387,10 +414,12 @@ def execute_case(env, case, process):
         yield request
         if process.event_log_flag:
             event_counter = process.event_counter
+            start = env.now
             log.add_start_event(process, event_counter, case, "order completed", env.now)
         yield env.process(process.order_completed())
         if process.event_log_flag: 
-            log.add_end_event(process, event_counter, env.now)
+            duration = env.now - start
+            log.add_end_event(process, event_counter, duration)
 
 
     # remove the case from the active cases since it's now done