diff --git a/CumulativeStatistics.cpp b/CumulativeStatistics.cpp
index edcef23..171914d 100644
--- a/CumulativeStatistics.cpp
+++ b/CumulativeStatistics.cpp
@@ -8,8 +8,8 @@
 **************************************************************************/
 #include "CumulativeStatistics.hpp"
 
-int CumulativeStatistics::busyTimeLoaders = 0;
-int CumulativeStatistics::busyTimeScale = 0;
+unsigned int CumulativeStatistics::busyTimeLoaders = 0;
+unsigned int CumulativeStatistics::busyTimeScale = 0;
 
 
 CumulativeStatistics::CumulativeStatistics()
@@ -17,22 +17,22 @@ CumulativeStatistics::CumulativeStatistics()
 
 }
 
-void CumulativeStatistics::appendLoadersBusyTime(int time)
+void CumulativeStatistics::appendLoadersBusyTime(unsigned int time)
 {
     CumulativeStatistics::busyTimeLoaders += time;
 }
 
-void CumulativeStatistics::appendScaleBusyTime(int time)
+void CumulativeStatistics::appendScaleBusyTime(unsigned int time)
 {
     CumulativeStatistics::busyTimeScale += time;
 }
 
-int CumulativeStatistics::getLoadersBusyTime()
+unsigned int CumulativeStatistics::getLoadersBusyTime()
 {
     return CumulativeStatistics::busyTimeLoaders;
 }
 
-int CumulativeStatistics::getScaleBusyTime()
+unsigned int CumulativeStatistics::getScaleBusyTime()
 {
     return CumulativeStatistics::busyTimeScale;
 }
diff --git a/CumulativeStatistics.hpp b/CumulativeStatistics.hpp
index a144276..29dc4bc 100644
--- a/CumulativeStatistics.hpp
+++ b/CumulativeStatistics.hpp
@@ -14,15 +14,15 @@ class CumulativeStatistics
 {
 public:
     CumulativeStatistics();
-    static void appendLoadersBusyTime(int time);
-    static void appendScaleBusyTime(int time);
-    static int getLoadersBusyTime();
-    static int getScaleBusyTime();
+    static void appendLoadersBusyTime(unsigned int time);
+    static void appendScaleBusyTime(unsigned int time);
+    static unsigned int getLoadersBusyTime();
+    static unsigned int getScaleBusyTime();
     static void clear();
 
 private:
-    static int busyTimeLoaders;
-    static int busyTimeScale;
+    static unsigned int busyTimeLoaders;
+    static unsigned int busyTimeScale;
 };
 
 #endif // CUMULATIVESTATISTICS_HPP
diff --git a/DialogCharts.cpp b/DialogCharts.cpp
index e53064c..bc61a21 100644
--- a/DialogCharts.cpp
+++ b/DialogCharts.cpp
@@ -64,7 +64,7 @@ void DialogCharts::initBusyChart()
     this->chartBusy->setAnimationOptions(QChart::AllAnimations);
 
     this->chartBusy->createDefaultAxes();
-    int max = qMax(CumulativeStatistics::getLoadersBusyTime(), CumulativeStatistics::getScaleBusyTime());
+    unsigned int max = qMax(CumulativeStatistics::getLoadersBusyTime(), CumulativeStatistics::getScaleBusyTime());
     this->chartBusy->axes(Qt::Horizontal).back()->setRange(0, DataProvider::getCurrentClock());
     this->chartBusy->axes(Qt::Horizontal).back()->setTitleText("Clock");
     this->chartBusy->axes(Qt::Vertical).back()->setRange(0, max);
diff --git a/DialogSimulation.cpp b/DialogSimulation.cpp
index cd6617c..5dcfbaa 100644
--- a/DialogSimulation.cpp
+++ b/DialogSimulation.cpp
@@ -70,7 +70,7 @@ void DialogSimulation::initializeSimulationTable()
     strLstHeaders << "Clock t" << "LQ(t)" << "L(t)" << "WQ(t)" << "W(t)" << "Loader Queue" << "Weigh Queue" << "Future Event List" << "B L" << "B S";
     ui->tableWidgetSimulation->setHorizontalHeaderLabels(strLstHeaders);
     QSettings settings;
-    ui->tableWidgetSimulation->setRowCount(settings.value("simulation/count").toUInt());
+    ui->tableWidgetSimulation->setRowCount(settings.value("simulation/count").toInt());
 
 
     // Load past state
@@ -102,7 +102,7 @@ void DialogSimulation::executeSimulation()
     LoadingQueue loadingQueue;
     auto loadingQueueCount = settings.value("simulation/itemsInitialize/loadingQueue").toUInt();
     for (unsigned int i = 0; i < loadingQueueCount; ++i) {
-        loadingQueue.addTruck(trucks.at(i));
+        loadingQueue.addTruck(trucks.at(int(i)));
     }
 
     // Loaders
@@ -111,7 +111,7 @@ void DialogSimulation::executeSimulation()
     auto loaderCount = settings.value("simulation/itemsInitialize/loader").toUInt();
     loaderCount += loadingQueueCount;
     for (unsigned int i = loadingQueueCount; i < loaderCount; ++i) {
-        loaders.addTruck(trucks.at(i));
+        loaders.addTruck(trucks.at(int(i)));
     }
 
     // Weigh queue
@@ -120,7 +120,7 @@ void DialogSimulation::executeSimulation()
     auto weighQueueCount = settings.value("simulation/itemsInitialize/weighQueue").toUInt();
     weighQueueCount += loaderCount;
     for (unsigned int i = loaderCount; i < weighQueueCount; ++i) {
-        weighQueue.addTruck(trucks.at(i));
+        weighQueue.addTruck(trucks.at(int(i)));
     }
 
     // Scale
diff --git a/DialogSimulation.hpp b/DialogSimulation.hpp
index da63d7d..67eda6d 100644
--- a/DialogSimulation.hpp
+++ b/DialogSimulation.hpp
@@ -29,7 +29,7 @@ class DialogSimulation : public QDialog
     enum Columns {
         Clock, LQt, Lt, WQt, Wt, LoaderQueue, WeighQueue, FutureEventList, Bl, Bs
     };
-    explicit DialogSimulation(QWidget *parent = 0);
+    explicit DialogSimulation(QWidget *parent = nullptr);
     ~DialogSimulation();
 
 public slots:
diff --git a/DumpTruck.cpp b/DumpTruck.cpp
index 9edd26f..da3bb74 100644
--- a/DumpTruck.cpp
+++ b/DumpTruck.cpp
@@ -8,7 +8,7 @@
 **************************************************************************/
 #include "DumpTruck.hpp"
 
-DumpTruck::DumpTruck(int index, QObject *parent) : QObject(parent), index(index)
+DumpTruck::DumpTruck(unsigned int index, QObject *parent) : QObject(parent), index(index)
 {
 
 }
@@ -23,7 +23,7 @@ QString DumpTruck::getName() const
     return "DT" + QString::number(this->index);
 }
 
-int DumpTruck::getIndex() const
+unsigned int DumpTruck::getIndex() const
 {
     return this->index;
 }
diff --git a/DumpTruck.hpp b/DumpTruck.hpp
index a6bbbfe..e809eb4 100644
--- a/DumpTruck.hpp
+++ b/DumpTruck.hpp
@@ -18,18 +18,18 @@ class DumpTruck : public QObject
     enum State {
         None, InLoaderQueue, Loading, InWeighQueue, Weighing, Traveling
     };
-    explicit DumpTruck(int index, QObject *parent = nullptr);
+    explicit DumpTruck(unsigned int index, QObject *parent = nullptr);
 
     void setState(State state);
     QString getName() const;
-    int getIndex() const;
+    unsigned int getIndex() const;
     State getState() const;
 
 signals:
 
 public slots:
 private:
-    int index = -1;
+    unsigned int index = 0;
     State state = None;
 };
 
diff --git a/FutureEventList.cpp b/FutureEventList.cpp
index a0a1a1e..37af067 100644
--- a/FutureEventList.cpp
+++ b/FutureEventList.cpp
@@ -71,14 +71,14 @@ Event *FutureEventList::getNextEvent()
     return this->lstEvents.at(index);
 }
 
-Event *FutureEventList::atTruck(int truckIndex) const
+Event *FutureEventList::atTruck(unsigned int truckIndex) const
 {
     if(this->lstEvents.isEmpty()) {
         return nullptr;
     }
 
     for (int i = 0; i < this->lstEvents.size(); ++i) {
-        int index = this->lstEvents.at(i)->getTruck()->getIndex();
+        unsigned int index = this->lstEvents.at(i)->getTruck()->getIndex();
 
         if(index == truckIndex) {
             return this->lstEvents.at(i);
diff --git a/FutureEventList.hpp b/FutureEventList.hpp
index f8b317c..28f1e46 100644
--- a/FutureEventList.hpp
+++ b/FutureEventList.hpp
@@ -20,7 +20,7 @@ class FutureEventList
     void clear();
     QString getString() const;
     Event* getNextEvent();
-    Event* atTruck(int truckIndex) const;
+    Event* atTruck(unsigned int truckIndex) const;
 
 signals:
 
diff --git a/Loader.cpp b/Loader.cpp
index 84923ea..75447f2 100644
--- a/Loader.cpp
+++ b/Loader.cpp
@@ -30,7 +30,9 @@ bool Loader::addTruck(DumpTruck *truck)
 
         truck->setState(DumpTruck::Loading);
 
-        short time = DataProvider::getRandomLoadingTime() + DataProvider::getCurrentClock();
+        unsigned int randomLoadingTime = uint(DataProvider::getRandomLoadingTime());
+
+        unsigned int time = randomLoadingTime + DataProvider::getCurrentClock();
         Event *event = new Event(Event::EL, time, truck);
         FutureEventList::getInstance()->addEvent(event);
 
diff --git a/MainWindow.cpp b/MainWindow.cpp
index cf6758b..c2fb7d8 100644
--- a/MainWindow.cpp
+++ b/MainWindow.cpp
@@ -191,18 +191,18 @@ void MainWindow::saveData()
 void MainWindow::loadData()
 {
     QSettings settings;
-    ui->spinBoxSimulationCount->setValue(settings.value("simulation/count").toUInt());
-    ui->spinBoxNumberOfTrucks->setValue(settings.value("simulation/itemsInitialize/trucks").toUInt());
-    ui->spinBoxNumberOfTrucksInLoadingQueue->setValue(settings.value("simulation/itemsInitialize/loadingQueue").toUInt());
-    ui->spinBoxNumberOfTrucksInLoaders->setValue(settings.value("simulation/itemsInitialize/loader").toUInt());
-    ui->spinBoxNumberOftrucksInWeighQueue->setValue(settings.value("simulation/itemsInitialize/weighQueue").toUInt());
+    ui->spinBoxSimulationCount->setValue(settings.value("simulation/count").toInt());
+    ui->spinBoxNumberOfTrucks->setValue(settings.value("simulation/itemsInitialize/trucks").toInt());
+    ui->spinBoxNumberOfTrucksInLoadingQueue->setValue(settings.value("simulation/itemsInitialize/loadingQueue").toInt());
+    ui->spinBoxNumberOfTrucksInLoaders->setValue(settings.value("simulation/itemsInitialize/loader").toInt());
+    ui->spinBoxNumberOftrucksInWeighQueue->setValue(settings.value("simulation/itemsInitialize/weighQueue").toInt());
     ui->checkBoxTruckInScale->setChecked(settings.value("simulation/itemsInitialize/scale").toBool());
 }
 
 void MainWindow::on_pushButtonSimulation_clicked()
 {
-    unsigned int numberOfTrucks = ui->spinBoxNumberOfTrucks->value();
-    unsigned int totalOtherTrucksCount = ui->spinBoxNumberOfTrucksInLoadingQueue->value();
+    int numberOfTrucks = ui->spinBoxNumberOfTrucks->value();
+    int totalOtherTrucksCount = ui->spinBoxNumberOfTrucksInLoadingQueue->value();
     totalOtherTrucksCount += ui->spinBoxNumberOfTrucksInLoaders->value();
     totalOtherTrucksCount += ui->spinBoxNumberOftrucksInWeighQueue->value();
     totalOtherTrucksCount += ui->checkBoxTruckInScale->isChecked() ? 1 : 0;
diff --git a/MainWindow.hpp b/MainWindow.hpp
index d5adbc5..55b9d1a 100644
--- a/MainWindow.hpp
+++ b/MainWindow.hpp
@@ -20,7 +20,7 @@ class MainWindow : public QMainWindow
     Q_OBJECT
 
 public:
-    explicit MainWindow(QWidget *parent = 0);
+    explicit MainWindow(QWidget *parent = nullptr);
     ~MainWindow();
 
 private slots:
diff --git a/Scale.cpp b/Scale.cpp
index 79283ca..03ced95 100644
--- a/Scale.cpp
+++ b/Scale.cpp
@@ -26,7 +26,7 @@ bool Scale::addTruck(DumpTruck *truck)
             return false;
         }
         truck->setState(DumpTruck::Weighing);
-        int time = DataProvider::getRandomWeighingTime() + DataProvider::getCurrentClock();
+        unsigned int time = uint(DataProvider::getRandomWeighingTime()) + DataProvider::getCurrentClock();
         Event *event = new Event(Event::EW, time, truck);
         FutureEventList::getInstance()->addEvent(event);
         return true;
@@ -68,7 +68,7 @@ void Scale::processEvents(WeighQueue &weighQueue)
             if(event->getEventType() == Event::EW && event->getTime() == DataProvider::getCurrentClock()) {
                 CumulativeStatistics::appendScaleBusyTime(timePenalty);
                 // At this time, weighing is finished and we must add new event for ALQ and also clear scale
-                short time = DataProvider::getRandomTravelTime() + DataProvider::getCurrentClock();
+                auto time = uint(DataProvider::getRandomTravelTime()) + DataProvider::getCurrentClock();
                 Event *alqEvent = new Event(Event::ALQ, time, event->getTruck());
                 futureList->removeEvent(event);
                 futureList->addEvent(alqEvent);