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Fighter pilots often find themselves in situations where they need to make quick decisions. Therefore an intelligent decision support system that suggests how the fighter pilot should act in a specific situation is vital. The aim of this project is to investigate and evaluate grammatical evolution paired with behaviour trees to develop a decision support system. This support system should control a simulated fighter pilot during an airborne reconnaissance mission. This thesis evaluates the complexity of the evolved trees and the performance, and robustness of the algorithm. Key factors were identified for a successful system: scenario, fitness function, initialisation technique and control parameters. The used techniques were decided based on increasing performance of the algorithm and decreasing complexity of the tree structures. The initialisation technique, the genetic operators and the selection functions performed well but the fitness function needed more work. Most of the experiments resulted in local maxima. A desired solution could only be found if the initial population contained an individual with a BT succeeding the mission. However, the implementation behaved as expected. More and longer simulations are needed to draw a conclusion of the performance based on robustness, when testing the evolved BT:s on different scenarios. Several methods were studied to decrease the complexity of the trees and the experiments showed a promising variation of complexity through the generations when the best fitness was fixed. A feature was added to the algorithm, to promote lower complexity when equal fitness value. The results were poor and implied that pruning would be a better fit after the simulations. Nevertheless, this thesis suggests that it is suitable to implement a decision support system based on grammatical evolution paired with behaviour trees as framework.

Malicious software or malware are constantly on the rise and lately, we observe threats that differ from what we have seen before. Threats tend to penetrate through existing prevention measures thus a choice of studying recent malware was highly appealing. To narrow down the research, a selection of analysing the emerging threat landscape on mobile platforms was chosen due to its progressive publicity. The study’s result section has been divided into three separate parts. The first chapter of the results, consists of a Problem Analysis which covers the topic regarding crucial aspects of mobile devices, how user behaviour affects the probability of plausible infections. Also, a questionnaire has been sent out to 100 participants to discover particular user behaviour with a mobile device. Second chapter Malware Research explores previous and recent detected malware, in addition to their characteristics. Last chapter Security Policy, provides a functional IT security policy that can be implemented and used as a guideline in organisations. The policy is primarily intended to guide mobile users towards safer management and usage in a workplace or of personal use. Research revealed that there is a significant link between user behaviour and device management for a mobile user to get potentially infected by malware. Furthermore, mobile malware is progressive and continuously adapting from users habits of devices and applications.

This study investigates the suggestion system of a mobile browser. The goal of a suggestion system is to assist the user by presenting relevant suggestions in an ordered list. By weighting the different types of suggestions presented to the user, such as history, bookmarks etc., it is investigated how this affects the performance of the suggestion sys- tem. The performance is measured using the position, error and Mean Reciprocal Rank of the chosen suggestion as well as the number of written characters. It is also measured if the user chose to not use the suggestion system, by searching or entering the entire URL. The weights were estimated using a Genetic Algorithm. The evaluation was done by performing an A/B test, were the control group used an unweighted system and the test group used the weights estimated by the genetic algorithm. The results from the A/B test were statistically analyzed using BEST and Bootstrap. The results showed an improvement of position, number of written characters, MMR and the error. There was no change in how much the user used the suggestion system. The thesis concluded that there is a correlation between the position of the desired suggestion and when the user stops typing, and that weighting types is a way to improve said position. The thesis also concludes that there is a need for future work in regards to evaluation of the optimization algorithm and error measurement.

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No description available.

By utilising graphical modelling languages, software developers can design large systems while keeping the architecture simple and understandable. Another benefit of using modelling languages is the possibility to automatically generate code, saving both time and reducing human errors in code. In addition, through the usage of well defined and executable models, the system can be tested and analysed as early as during the design phase. Doing so, potential errors in the design can be found and corrected during the design phase, saving time and other resources. In this thesis we present a method for analysing executable model representations of systems through three steps. First the model is transformed to a suitable format for analysis. The result of the transformation is then analysed using analysis tools. Lastly, the result of the analysis is mapped back to the source model. The developed method was assessed through a proof-of-concept using a transformation from the action language for fUML, an executable modelling language. The target of the transformation was ALF, an intermediate language designed for analysis in the SWEET tool. The analysis of the source was performed in regards to properties of the system, such as program flow and value bounds. Through the proof-of-concept, the proposed method was shown to be a viable option for analysing fUML models.

Många avancerade och komplexa system används idag run-tom i världen och flera av dem är väldigt viktiga att de fungerar och fortsätter göra det. För att inte förstöra dessa system så kan en dry-run användas om någonting behöver uppdateras eller ändras. Med dry-run menas att en ändring aldrig händer men att resultaten av ändringen kan visas på en skärm eller förmedlas på något sätt. Det här arbetet undersöker om unionmount är en bra lösning för att implementera detta. Arbetetvisar att det finns möjligheter för att implementeras men det finns en del problem som behöver lösas. Detta kan också bero på vilket system man vill implementera det i.

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The goal of this thesis is to design a coprocessor expansion board for an On Board Computer (OBC) using Commersial Off The Shelf (COTS) components. This is done in order to meet the increasing demand of more processing power as spacecrafts become more autonomous. After evaluating a number of different options, the LS1046A from ARM was chosen as the processing unit. This would increase the processing power from the current 110 Dhrystone Million Instructions Per Second (DMIPS) to a theoretical 22 560 DMIPS. The schematic was designed in DxDesigner, and after the layout was completed signal integrity simulations were performed in HyperLynx. After modifications to termination resistances, the simulations showed good signal integrity confirming proper routing of the signals. After receiving the manufactured Printed Circuit Board (PCB) with all components mounted, some tests could be performed confirming that the power distribution and the system clock was functioning properly.