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The study considers the scheduling problem of identical parallel machines subject to minimization of the maximum completion time and the maximum tardiness expressed in a linear convex objective function. The maximum completion time or makespan is the date when the last job to be completed leaves the system. The maximum tardiness is indicated by the job that is completed with the longest delay rela

The Electronic Stability Program (ESP) is becoming increasingly popular in vehicles as a means to prevent spin-out and lane departure accidents, and is nowadays a standard feature in most cars. From 2012 the ESP will also be a standard feature in buses. As a first step, this thesis is dedicated to implementing an ESP for an articulated bus in simulation using Matlab/Simulink. The core of the ESP i

There are different tools for automatic code generation today. A comparison between different tools is necessary in order to highlight the differences between the tools according to specific aspects. TargetLink from dSPACE and Real-Time Workshop Embedded Coder from The MathWorks are two tools that have been evaluated and tested in order to point out the differences between the performance of those

Due to new emission legislations in Europe and in the USA truck manufacturers are facing new difficulties when it comes to meeting these demands. This new legislation will demand more accurate models for simulation and malfunction diagnosis. The NOx emissions, covered in these new laws, are intimately linked to combustion temperatures and these temperatures may be decreased by means of exhaust gas

This master's thesis is about the implementation and evaluation of a small object-oriented automation system. By using a realtime Java VM from Jamaica, a sheet feeding magazine from the machine Tetra Aptiva Aseptic has been controlled. The expectations included to achieve more structured and safer programming, better documentation through UML and to separate application developers from develop

In modern batch plants, alarm floods overwhelming the operator is a common problem of ever increasing severity. As plant hardware increase in complexity and performance, measures such as downtime and meantime between failures, increase in importance and the need for a well-functioning exception handling routine therefore grows critical. In order to minimize downtime and hence boost production effi

This thesis is focused on modelling the pumping of the human heart. The modelling is limited to the left heart. Flows through the left heart were visualized by pathlines, streamlines and curl from 3D-velocity data acquired using 3D-velocity encoded magnetic resonance imaging (MRI). A mathematical model was developed based on control volume analysis, 3D-flow analysis and the latest developments in

People that have driven a car with a trailer at high speed know that the trailer can begin to oscillate. This oscillation is known as snake behavior. How much the car and trailer starts to oscillate depends on how the trailer is loaded. An empty trailer does not tend to oscillate, while a heavy loaded trailer, with the load centered over the trailer axle, oscillates more easily. For a normal perso

This thesis presents an implementation of a positioning and navigation system for a mobile robot using ultrasonic pulses and passive sensors that are part of a sensor network. The system uses the Telos Tmote Sky sensor-boards running Contiki. In addition to the Tmote Sky the mobile robot consists of a number of processors and is equipped with position encoders for the wheels in order to be able to

This thesis presents an implementation of a positioning and navigation system for a mobile robot using ultrasonic pulses and passive sensors that are part of a sensor network. The system uses the Telos Tmote Sky sensor-boards running Contiki. In addition to the Tmote Sky the mobile robot consists of a number of processors and is equipped with position encoders for the wheels in order to be able to

The balancing act of an inverted pendulum with a robotic manipulator is a classical benchmark for testing modern control strategies in conjunction with fast sensor-guided movements. From the control design perspective, it presents a challenging and difficult problem as the system is open-loop unstable and includes nonlinear effects in the actuators, such as friction, backlash, and elasticity. In a

This thesis addresses the issue of Information Systems (IS) security in pharmaceutical manufacturing which is closely related to the ISA 99 standard. The ISA 99 'Security for industrial Automation and Control Systems' standard is focused on the work for securing process automation systems from IS security threats. The main thought behind the ISA 99 standard is that a high level of IS secur

In this thesis simple vehicle models are compared to more advanced models. The parameters in the simple models have to be chosen in such a way, that the model behaviour is as close to the advanced model as possible. This parameter optimisation is done with help of The Optimica Compiler, wich generates AMPL files that solves the problems. To run a successful parameter estimation there is a need for

Optimal paths are useful when testing the performances of vehicles. In this thesis, optimal paths for vehicle models created in Modelica have been obtained. The optimal paths have been obtained by applying the theory of optimal control. The optimal control problem has been formulated with the Optimica language and has been solved with AMPL and IPOPT. Two approaches for finding optimal paths have b

The aim of the thesis is to model engine physics and dynamics and to design controllers based on the physical model. By implementing equations and solving them it's possible to describe the major phenomena in a four stroke engine running in HCCI mode. To describe the cycle-tocycle connection in the model a wall temperature model was introduced. This wall model is used to simulate the engine dy

TrueTime is a MATLAB/Simulink-based simulator for real-time control systems that has been developed at the Department of Automatic Control, LTH. The aim of this thesis is to port the TrueTime kernel block to the open-source Scilab/Scicos simulation environment. The original kernel block is a variable-step, discrete S-function written in C++. In this work, the Scicos engine should replace the Simul

In the process industry general TITO systems, i.e. systems with two inputs and two outputs, are usually assumed to be two separate systems. If the system is strongly coupled, the performance is generally poor, but usually nothing is done about this since there are no automatic means to improve it. The aim of this master's thesis is to develop a module with a completely automated design procedu

More than 90 % of all computers are embedded in different types of systems, for example mobile phones and industrial robots. Some of these systems are real-time systems; they have to produce their output within certain time constraints. They can also be safety critical; if something goes wrong, there is a risk that a great deal of damage is caused. Industrial Extended Automation System 800xA, deve

This Master's Thesis presents the development of methods for improved GPS navigation on Wayfinder Navigator, a mobile phone based navigation system developed by Wayfinder Systems. Focus has been put on off track detection, i.e. to detect a user diverging from the route given by the navigation system, and how the GPS position is presented to the user by the application. Improving off track dete

As a part of the RUNES project a robot has been developed and it has as a part of this theses been improved with an obstacle avoidance component. Work has also been done to make room for additional components on the Tmote sky (one of the micro controllers mounted on the robot) such as a power control component developed at KTH. Attempts has also been made to try to enhance the performance of the r