This thesis is part of a project, Working on Venus, funded by the Knut and Alice Wallenberg Foundation (one of the largest Swedish funders of research) and developed by KTH in collaboration with Linkӧping University. The goal of this project is to create a lander able to investigate the planet Venus and to work under extreme conditions, i.e. it has to be able to withstand at high levels of radiation and high temperatures such as that of Venus surface (that is about 460 °C) without integrating a dedicated bulky cooling system to reduce the overall weight and volume of the system. In this thesis it will be investigated in detail the 4H-SiC performances to realize a CMOS image sensor for UV photography that operates at high temperature. This work will include discussions and proposals on possible future applications, such as the realization of 4H-SiC phototransistors

While the relation between smartphone user behavior and contextual factors have been explored in previous research, the mobile networks’ influence on the smartphone user behavior is largely unknown. Through statistical analysis of a data set collected globally from ˜ 1000 users by an Android app called Ericsson Apps, this study investigates how the users’ app choices and app usage depend on the network performance. The results show, for instance, that the choice of app depends strongly on the network performance, suggesting that it is a factor in the users’ app choices. For example, Swedish users are ˜ 3 times more likely to use Facebook on LTE than when disconnected, i.e., no access to the mobile networks, while ˜ 4.6 times more likely to make a phone call when disconnectedthan on LTE. Additionally, the data analysis finds a demand for better performance in the mobile networks as the downlink data consumption grows linearly without decline, with respect to network performance, for media and video types of apps.

För laborationer i datortekniksundervisning på KTH används för närvarande Nios II-processorn på utvecklingskortet DE2. Processorn skiljer sig från den MIPSprocessor som används i resten av kursen och den tillhörande utvecklingsmiljön är komplicerad. Ett tidigare kandidatexamensarbete har undersökt möjligheten att byta ut den nuvarande plattformen mot utvecklingskortet Uno32 från Digilent Chipkit. Planer finns även att utöka kursen till att innefatta ett projektmoment där studenterna använder plattformen självständigt. I syfte att utvärdera hårdvaruplattformen utvecklas en serie exempelprojekt som även demonstrerar hårdvaran. Under arbetet utvecklas också en fri utvecklingsmiljö som ska vara enkel att installera och använda för studenterna. Slutsatserna som dras är att den fria utvecklingsmiljön som tas fram är ett framtidssäkert alternativ som är mer hårdvarunära än Digilent MPIDE, men smidigare än Microchip Mplab X då ingen programmeringsutrustning krävs. Från de utvecklade exempelprojekten dras slutsatsen att hårdvaruplattformen är en möjlig projektplattform för datortekniksundervisning, men att den behöver testas av studenter i undervisningen. / Laboratory exercises in the computer hardware engineering course at Royal Institute of Technology are currently based around the Nios II processor running on the Altera DE2 development board. The Nios II processor differs from the MIPS processor taught during lecures, and the accompanying development environment is complicated to use. A previous bachelor’s thesis has explored the possibility of replacing the current platform with the Uno32 development board from Digilent Chipkit. Plans also exist to extend the course with more independent project work, where students would use the hardware platform on their own. To evaluate the hardwareplatform, a series of example projects are developed. These projects are also aimed to be used in demonstion of the platform and as a base for the students’ own projects. In the process, a toolchain and development environment based on free software is developed with the goal of being easy to install and use by students. In conclusion, the developed free software toolchain is a future-proof and viable alternative to Digilent Chipkit MPIDE and Microchip Mplab X. The free software toolchain is lower level than the MPIDE Arduino environment, but easier to use than Mplab X since extra programming hardware is not needed. The developed example projects hint that Uno32 is a viable hardware platform for education, but more thorough student testing is required to draw further conclusions.

The existent of pharmaceutical drugs in our aquatic media is a preeminent burden for the environment effect including health fitness issues. The presence of tiny amount of organic and inorganic pharmaceutical drugs including hormones, birth control pills, NSAID, antibodies can causes a huge destruction for our living entity now a days. According to the report of WHO (World Health Organization), it is a matter of concern about the alarming existence of pharmaceutical drugs in our daily water supply systems because of these small portion of Pharmaceutical activated compound can cause enormous health effect for both animals and human being. The photocatalytic degradation of Ibuprofen and cetirizine has been chosen according to their large scale presence with waste water and also creating a benchmark with our conventional and nonconventional treatment processes of our waste water treatment plants to obtain pristine water. Even though our meticulous environmental regulation policy, Ibuprofen and Cetirizine both are vastly used by large portion of community in our society and they are major pharmaceutical contaminant of WWTP (waste water treatment plant) for their enormous uses by human being. TiO2, ZnO and several clay nanopowder with photocatalytic compounds are familiar as photocatalyst and their uses under UV light generator can able to degrade both pharmaceutical drugs. Three different types of TiO2 components (Anatase, Rutile and mixture of Anatease and Rutile) were used to determine the best efficient material among photocatalyst chemical nanopowder. ZnO and montmorillonite clay particles were tested for further verification of photocatalytic characteristics. The entire experiment was accomplished by batch reaction under several operating parameters consideration such as changing pH values, time and concentration. All parameters have very important influence on ibuprofen and cetirizine degradation was verified. Recently many efforts have been made to increase the efficiency of photocatalytic materials. By addition of MWCNT (Multi Walled Carbon Nano Tube) with photocatalyst nano powder can increase the photocatalytic efficiency by increasing recombination time was demonstrated here after examination. The entire goal of this thesis was to develop a suitable, sustainable and efficient hybrid nanofiber composite also successfully investigated. Using photocatalytic nanopowders to degrade the PhACs (Pharmaceutical Active Compounds) in WWTP are not very easy to separate after execution. Therefore, the idea of hybrid nanofibers was fabricated here to get remedy from separation problem. Hybrid nanofibers assembled by PAN (Polyacrylonitrile)/TiO2 where TiO2 were immobilized over electrospun PAN nanofibers. The nanofiber has been fabricated appropriately with electrospinning process by using N, N-dimethyl formamide (DMF), PAN and tetrabutyl titanate [Ti(OBu)4] sol-gel composites. TiO2 immobilized on PAN nanofiber after implementing hydrothermal process. The fabricated hybrid nanofibers were scrutinized with different characterization tools such as X-ray diffraction, field emission scanning electron microscopy, thermo gravimetric analysis and energy dispersive X-ray (EDX) spectroscopy. The outcome of fiber analysis represents the flexibility and large surface area of the hybrid nanofibers. The as-fabricated nanofibers were tested with ibuprofen solution under UV light irradiation. Impressive performances by fabricated nanofibers were examined for ibuprofen degradation after several minutes’ photocatalytic reaction.

Inom Totalförsvarets forskningsinstitut och Försvarsmakten finns behov av att enklare och mer effektivt (med avseende på kostnad och tid) kunna skapa bättre, mer realistiska och objektiva beteenden för de syntetiska aktörer som ingår i Försvarsmaktens simuleringsbaserade beslutsstöds- och träningsapplikationer. Den traditionella metoden för anskaffning av kunskap om ett beteende, vid utveckling av beteendemodeller, är att arbeta med experter inom ämnesområdet. Den här processen är ofta tidskrävande och dyr. Ett annat problem är att komplexiteten är begränsad av expertens kunskap och dess kognitiva förmågor. För att möta problemen undersöker den här studien en alternativ metod till utvecklandet av beteendemodeller med hjälp av maskininlärningsalgoritmer. Det här tillvägagångsättet kallas datadriven beteendemodellering. Datadriven beteendemodellering skiljer sig avsevärt från den traditionella domänexperts-metoden. I den datadrivna bygger datorprogram självständigt beteendemodellerna utifrån data och observationer utan mänsklig inverkan, medan domänexperts-metoden utvecklas för hand av människor. I studien utvecklas datadriven beteendemodellering med genetisk programmering, en maskininlärningsteknik inspirerad av den biologiska evolutionen. Tekniken går ut på att datorn försöker hitta de bästa möjliga programmen för att lösa en användardefinierad uppgift med hjälp utav, bland annat, en lämplighetsfunktion som betygsätter programmen. I den här studien byggs ett system som utför datadriven beteendemodellering med genetisk programmering för att utveckla en mjukvaruagents beteende i en simulator. I projektet användes en vargsimulator för att försöka lära upp en varg att jaga och sluka flyende får. Simulatorgenererad data används av agenten för att lära sig rörelsebeteenden via utforskning (eng. trial-and-error). Systemet är generellt genom dess förmåga att kunna anpassas till andra simuleringar och olika beteendemodeller. Resultatet av experimenten utförda med systemet visar att en upplärd varg lyckades utveckla ett skickligt datadrivet beteende där den jagade och slukade alla 46 får på under tio minuter. I jämförelse lyckades en fördefinierad skriptad centroidalgoritm äta upp fåren på ungefär åtta minuter. Slutsatsen är att lyckade och effektiva datadrivna beteenden kan utvecklas med genetisk programmering, åtminstone för detta problem, om de tillåts tillräckligt lång simuleringstid, bra konfiguration samt en gynnsam och rättvis lämplighetsfunktion. / Within the Swedish Defence Research Agency and the Swedish Armed Forces there is a need to easier and more efficiently (in terms of cost and time) create better, more realistic and objective behaviour for the synthetic actors involved in the Armed Forces’ simulation-based decision support, and training applications. The traditional method for the acquisition of knowledge about a behaviour, in the development of behavioural models, is working with experts on the subject. This process is often time consuming and expensive. Another problem is that the complexity is limited by the expert knowledge and his cognitive abilities. To address the problems this study investigates an alternative approach to the development of behavioural models. The new method develops behavioural models of machine learning algorithms instead of manually creating models. This approach is called data-driven behaviour modelling. Data-driven behaviour modelling differs significantly from the traditional subject-matter expert method. The data-driven computer program creates autonomous behaviour models based on data and observations without human influence, while the subject-matter expert method is developed manually by humans. In this study data-driven behaviour modelling with genetic programming is developed, a machine learning technique inspired by the biological evolution. The technique let’s the computer trying to find the best possible programs in order to solve a user defined task with help of, for instance, a fitness function that rates the programs. This thesis presents a system that performs data-driven behaviour modelling with genetic programming to develop a software agent's behaviour in a simulator. The study used a wolf simulator to try to teach a wolf to hunt and devour fleeing sheep. Simulator-generated data is used by the agent to learn behaviours through exploration (trial-and-error). The system is generally applicable by its ability to be adapted to other simulations with simple adjustments in a configuration file. The system is also adaptable to many different behaviour models by its basic execution structure. The results of the experiments performed with the system show that a trained wolf succeeded to develop a clever data-driven behaviour where it hunted and devoured all of the 46 sheeps in less than ten minutes. In comparison a predefined centroid algorithm managed to eat the sheep in about eight minutes. The conclusion is that successful and efficient data-driven behaviours can be developed, at least regarding this problem, if allowed a sufficiently long simulation time, good configuration and a favourable and equitable fitness function.

Företaget AB ska byta sitt affärssystem på grund av att dagens lösning är över 30 år gammal och svårt att underhålla. Behovet av nya funktionalitet i verksamheten kräver att företaget byter affärssystemet till ett nytt system, byggd på nya teknik för att det ska vara lönsamt att underhålla och att det ska fungera x-antal år till. Efter en lång undersökningsperiod har företaget AB valt ett standardsystem för försäljning av sina produkter både på kassa och automater och sina digitala kanaler som består av webbplats och mobila Appar. Syftet med denna undersökning har varit att besvara frågan om ett integrationslager mellan ett standard affärssystem och webbfront kan lösa problem med omkostnader för förvaltning och även säkra känslig data och intrång till försäljningssystemet. För att kunna besvara frågorna kring problemet har diverse relavanta litteratur artiklar lästs samt datainsamlingen har skett genom facktliga litteratur och tidningar, Internet och manualer för att kunna ta fram kartan över relevant data för olika externa och interna intressenter för affärssystemet och utifrån verksamhetens behov. Diskussioner med IT-arkitekter och systemutvecklare i olika möten om företagets behov har också hjälpt till lösningsförslag som beskrivtis i denna dokument. / The company AB will change its business system which was built during the last 30 years, its old technology and also the cost of maintenance. The needs of the new features require that the business system should be built on newer technologies to be more profitable and has longer life time. After further analysis, the company AB has chosen a standard sale system to sell its products both in cashier, ATM and their digital channels consisting of websites and mobile apps. The aim of this study was to answer if an integration layer between a standard business applications and Web fronts can reduce overhead costs for maintenance and also securing sensitive data and data intrusion into the sales system. In order to answer questions about this issue, various of relevant literature articles have been read and data has been collected from fact books, literature and magazines, the Internet and manuals in order to create a map of relevant data for various internal and external stakeholders for the core business system and based on organizations needs. Discussions with IT architects and system developers in various meetings about the company's needs have also helped solution proposals explained in this document.

Analytics frameworks were initially created to run on bare-metal hardware so they contain scheduling mechanisms to optimise the distribution of the cpu load and data allocation. Generally, the scheduler is part of the analytics framework resource manager. There are different resources managers used in the market and the open-source community that can serve for different analytics frameworks. For example, Spark is initially built with Mesos. Hadoop is now using YARN. Spark is also available as a YARN application. On the other hand, cloud environments (Like OpenStack) contain theirs own mechanisms of distributing resources between users and services. While analytics applications are increasingly being migrated to the cloud, the scheduling decisions for running an analytic job is still done in isolation between the different scheduler layers (Cloud/Infrastructure vs analytics resource manager). This can seriously impact performance of analytics or other services running jointly in the same infrastructure as well as limit load-balancing, and autoscaling capabilities. This master thesis identifies what are the scheduling decisions that should be taken at the different layers (Infrastructure, Platform and Software) as well as the required metrics from the environment when mul-tiple schedulers are used in order to get the best performance and maximise the resource utilisation.

Mobile traffic is expected to grow rapidly over the next few years. This traffic increase will lead to a shortage of available bandwidth in the traditional frequency bands. As a solution to the shortage of bandwidth, the industry has started to look into acquiring additional spectrum to meet the future demands. However, substantial new spectrum can only be made available at higher frequencies than those in use today, where the propagation characteristics are more problematic. This thesis investigates the feasibility of different deployment alternatives for providing indoor coverage at high frequencies (10 GHz to 60 GHz). The required base station density in order to meet six coverage and capacity targets is compared for different frequencies and deployment concepts. Firstly, the deployments are studied in a single building scenario. Secondly, the results from the single building scenario are applied to a city scenario in order to study how a surrounding macro layer affects the indoor performance. In the single building scenario, deployment of outdoor micros were found to be suitable for low and moderate data rate/capacity requirements up to 30 GHz, and high capacity/data rates up to 15 GHz with the use of beamforming. Indoor deployments were required to achieve indoor coverage at 60 GHz and for high data rate/traffic requirements at lower frequencies. Distributed antenna systems were found unsuitable at higher frequencies due to large losses in the coaxial feeder cables. In the city scenario achieving dominance over the macro layer was problematic due to the large beamforming array used by the macro base stations. However, the data rates for the users served by the small cell deployments were found to be similar to the single building case. / Trafiken in mobiltelefonnäten förväntas växa snabbt de kommande åren, och denna trafikökning kommer att leda till en brist av bandbredd i de traditionella frekvensbanden. Som en lösning på detta har branschen börjat undersöka möjligheten att använda ytterligare spektrum. Stora mängder oanvänt spektrum finns dock enbart tillgängligt i mycket högre frekvenser än de som används i dagsläget, där utbredningsegenskaperna är sämre. Detta examensarbete undersöker potentialen för olika basstationskoncept för inomhustäckning i högre frekvenser (10 GHz till 60 GHz). Basstationstätheten för att nå sex olika täcknings- och kapacitetsmål undersöks för olika frekvenser och basstationskoncept. Först studeras koncepten i en ensam byggnad. Efter det används resultaten från den ensamma byggnaden för att undersöka hur inomhustäckningen och kapaciteten skulle påverkas i ett stadsscenario med ett macrolager på samma frekvens. I den ensamma byggnaden visade det sig att microbasstationer placerade utomhus passade till låga och måttliga datahastighetsoch kapacitetskrav upp till 30 GHz samt höga krav upp till 15 GHz med hjälp av strålformning. Inomhuskoncept krävdes för att nå samtliga krav för 60 GHz och för höga krav i lägre frekvenser. Distribuerade antennsystem visade sig olämpliga i högre frekvenser pga. stora förluster i koaxialkabeln. I stadsscenariot visade det sig problematiskt att uppnå dominans över macrobasstationerna pga. det stora antalet antennelement i strålformningen. Prestandan för de användare som betjänades av de små basstationskoncepten visade sig dock liknande scenariot med den ensamma byggnaden.

Low temperature epitaxy (LTE) of SiGe by chemical vapor deposition (CVD) has attracted dramatic attention during the last decade for CMOS and BiCMOS application. LTE relates to a temperature range of 350÷650 °C. The low temperature budget provides the possibility of integrating epitaxy in the process line when the sensitive active parts are already present on the chips. In this case, the benefits of LTE are to avoid the thermal mismatch between different layers in the transistors, preventing damages to the poly gate and to ensure the integrity of thin gate oxide. The challenge to deal with the lowering temperature process is the quality of epitaxial layer. In particular, the low temperature processing results in low growth rates and more oxygen (or water moisture) contamination in the layer growth. For these reasons, particular attention has been paid to islands formation at the interface and within the layer. Choosing appropriate Si precursor, optimizing the growth parameters and reducing oxygen (or moisture) contamination are critical issues for growing high quality epitaxial layers at low temperatures. This thesis work presents the characterization of layers grown using Trisilane (Si3H8), Germane (GeH4) and Hydrochloric acid (HCl) as precursor gases at LTE. Characterization tools were high-resolution scanning electron microscope (HRSEM), Secondary ion mass spectroscopy (SIMS), high-resolution x-ray diffraction (HRXRD) and noise measurements. The results of this work suggest that only electrical measurements are most sensitive way to study the effects of low amounts of contamination on crystal quality of LTE grown structures. It also shows that the presence of HCl in the chamber increases the noise level in these types of structures. This higher level of noise is believed to be a result of higher defect density due to the etching caused by HCl and metal contamination that could arise from the aging and the corrosion of the pipelines.

IPv6 over Low power WPAN (6loWPAN) is an adaption layer introduced between the link layer and the network layer in the TCP/IP protocol stack to t the IPv6 datagrams over the IEEE 802.15.4 link layer. 6loWPAN networks comprise of internet enabled resource-constrained smart objects which are interconnected with each other through the Internet Protocol (IPv6). In Internet of Things (IoT), smart devices of the 6loWPAN networks are connected to the unsecured public Internet. RPL (Routing Protocol for Low-Power and Lossy Networks) is the standardized routing protocol dened for routing IP datagrams over the lossy links in LLN (Low-Power and Lossy Networks). In IoT, all devices have a global identity and could be accessed from anywhere in the globe. Hence, security is an important factor in protecting the devices and their informational resources from adversaries. Security solutions must be highly e ective for smart objects considering their limited resources. Despite the state of the art crypto solutions providing information security, IPv6 enabled smart objects are vulnerable to attacks from outside and inside the 6LoWPAN networks. This thesis attempts to identify the intrusions aimed to disrupt 6LoWPAN networks and to prevent external adversaries taking advantage of the resource constrained 6LoWPAN environment. We review state of the art security attacks in conventional WSNs and the RPL-based LLNs. In order to improve the security within 6LoWPAN networks, we extend SVELTE (an IDS for the IoT) by adding ETX (Expected Transmissions) parameter in the 6Mapper. In RPL, ETX is a link reliability metric which indicates the number of successful IP datagram transmissions with respect to the Border Router. Monitoring the ETX value could prevent the Border Router and neighboring nodes to engage actively with the malicious intruder. We propose a geographic routing algorithm to identify the malicious node conducting attacks against ETX-based solutions. We also implement a lightweight rewall at the Border Router to prevent 6LoWPAN networks from external attackers. In this rewall we conduct a stateful deep packet inspection on the protocols adhering to the protocol stack for the 6LoWPAN networks. Our evaluation shows that the IDS module with ETX metric consumes negligible energy and very less CPU processing power. Our intrusion detection mechanisms improves the true positive rate of SVELTE.