diff --git a/src/main/java/fr/ntr/AccessPoint.java b/src/main/java/fr/ntr/AccessPoint.java
index d2ce6c7..45ee579 100644
--- a/src/main/java/fr/ntr/AccessPoint.java
+++ b/src/main/java/fr/ntr/AccessPoint.java
@@ -3,16 +3,13 @@ package fr.ntr;
 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
-import java.nio.file.Files;
-import java.nio.file.Paths;
 import java.util.List;
-import java.util.Random;
 
 import fr.ntr.scheduler.Scheduler;
 
 public class AccessPoint {
-    private List<User> users;
-    private Scheduler scheduler;
+    private final List<User> users;
+    private final Scheduler scheduler;
     /**
      * nombre de slots
      */
@@ -24,24 +21,14 @@ public class AccessPoint {
     /**
      * trame
      */
-    private ResourceBlock[][] frame;
-
-    /**
-     * Portée minimum et maximum de l'antenne
-     */
-    private final double min, max;
-
+    private final ResourceBlock[][] frame;
     private FileOutputStream outputDataFile;
 
     
-    public AccessPoint(Scheduler scheduler, ResourceBlock[][] frame, List<User> users, int timeSlotNb, int subCarrierNb, double min, double max) {
-        this.min = min;
-        this.max = max;
+    public AccessPoint(Scheduler scheduler, ResourceBlock[][] frame, List<User> users) {
         this.users = users;
         this.scheduler = scheduler;
         this.frame = frame;
-        this.timeSlotNb = timeSlotNb;
-        this.subCarrierNb = subCarrierNb;
     }
 
     /**
@@ -50,8 +37,6 @@ public class AccessPoint {
      */
     public void startSimulation(int duration) {
         try{
-            Files.deleteIfExists(Paths.get("export", this.users.size() + ".csv"));
-            new File("export").mkdir();
             this.outputDataFile = new FileOutputStream("export" + File.separator + this.users.size() + ".csv", true);
             outputDataFile.write("tick;x;y;user;bandwidth;delay;\n".getBytes());
         } catch(IOException e) {
@@ -120,7 +105,6 @@ public class AccessPoint {
     }
 
     private void reset() {
-        // TODO insert new UR
         for(int i = 0; i < timeSlotNb; i++) {
             for(int j = 0; j < subCarrierNb; j++) {
                 frame[i][j] = new ResourceBlock(0.0);
@@ -139,4 +123,12 @@ public class AccessPoint {
     public static int getSubCarrierNb() {
         return subCarrierNb;
     }
+
+    public static void setTimeSlotNb(int timeSlotNb) {
+        AccessPoint.timeSlotNb = timeSlotNb;
+    }
+
+    public static void setSubCarrierNb(int subCarrierNb) {
+        AccessPoint.subCarrierNb = subCarrierNb;
+    }
 }
diff --git a/src/main/java/fr/ntr/Main.java b/src/main/java/fr/ntr/Main.java
index b5d412d..50ada1b 100644
--- a/src/main/java/fr/ntr/Main.java
+++ b/src/main/java/fr/ntr/Main.java
@@ -1,12 +1,13 @@
 package fr.ntr;
 
-import fr.ntr.scheduler.MaxSNR;
-import fr.ntr.scheduler.ProportionalFair;
 import fr.ntr.scheduler.RoundRobin;
 import fr.ntr.scheduler.Scheduler;
 
+import java.io.File;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
+import java.util.Objects;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 
@@ -28,14 +29,29 @@ public class Main {
             }
             int timeSlotNb = 2;
             int subCarrierNb = 100;
+            File folder = new File("export");
+            if(!folder.exists() && !folder.mkdir()) {
+                    System.err.println("Cannot create export folder");
+                    System.exit(1);
+
+            }
+            Arrays.stream(Objects.requireNonNull(new File("export").listFiles()))
+                    .filter(File::isFile)
+                    .forEach(f -> {
+                        if(!f.delete()) {
+                            System.err.println("Cannot remove file " + f.getAbsolutePath());
+                        }
+                    });
+            AccessPoint.setTimeSlotNb(timeSlotNb);
+            AccessPoint.setSubCarrierNb(subCarrierNb);
             try(ExecutorService executor = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors())) {
                 for(int i = 2; i <= maximumLoad; i += 2) {
                     List<User> users = generateUsers(i, timeSlotNb, subCarrierNb);
                     ResourceBlock[][] frame = new ResourceBlock[timeSlotNb][subCarrierNb];
-                    //Scheduler scheduler = new MaxSNR(frame, users);
+                    // Scheduler scheduler = new MaxSNR(frame, users);
                     // Scheduler scheduler = new ProportionalFair(frame, users);
                     Scheduler scheduler = new RoundRobin(frame, users);
-                    AccessPoint accessPoint = new AccessPoint(scheduler, frame, users, timeSlotNb, subCarrierNb, 0, 50);
+                    AccessPoint accessPoint = new AccessPoint(scheduler, frame, users);
                     executor.submit(() -> accessPoint.startSimulation(numberOfTicks));
                 }
             }