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MANY (Many-core programming and resource management for high performance Embedded Systems) project aims to develop a programming environment for many-core embedded systems which would make faster development of applications possible. MANY focuses on exploiting parallelism and resource awareness. This thesis contributes to the project by investigating possible solutions for scheduling real-time tasks on many-core embedded systems while aiming to reduce power consumption whenever it does not affect the performance of the system. This thesis has implemented a basic power-aware scheduler for many-core real-time embedded systems. The system is capable of meeting hard-real time deadlines and it can save power by turning off cores which are not needed. This thesis lays the foundation for further developments in the mentioned field.

Search or social media giants are no longer the only individuals that face the problems of managing Big Data. Many of today's applications and services experience sudden bursts in growth, with increased data generation rates, that require storage and analysis support for large amounts of data. Traditional relational database management system (RDBMS) have been adapted to a distributed environment in an effort to make them suitable for Big Data, but they do not scale linearly and tend to obtain little extra performance as they grow in size. On the other hand, solutions built natively for a distributed environment, referred to as "Not only SQL" (NoSQL) provide a limited data model with few possible operations compared to structured query language (SQL). However, providing a data model with more complex, SQL like operations, raises some particular challenges in a distributed environment. This thesis presents the design of a data model on top of the CATS keyvalue store. The purpose of this data model is to provide support for more complex data, compared to the simple key-value operations currently supported by CATS. Objects containing a number of fields can be stored and retrieved. Secondary indexes on different fields allow the search of objects based on the value of these indexed fields. The thesis also presents mechanisms for colocating data that is used together in order to reduce the latency of operations by exploiting data locality. The ability to dynamically adapt the way data is saved to disk according to different data access patterns can also help to provide faster services. The evaluation of a prototype of the system provides measurements on the overhead associated with the data model compared to the underlying key-value store.

Abstract This master thesis implements a critical block: Fast Fourier Transform (FFT)/Inverse Fast Fourier Transform (IFFT) for standards using Orthogonal Frequency Division Multiplexing (OFDM). They are used in OFDM systems for modulating / demodulating subcarriers. The main goal of this thesis is to implement these blocks in a Field Programmable Gate Array (FPGA) using Very High Speed Integrated Circuit Hardware Description Language (VHDL). OFDM technology is used in multiple wireless communication standards including WLAN IEEE 802.11(a/g/n), WiMAX, LTE and DVB. 64-point FFT/IFFT blocks determines the complexity of an IEEE 802.11 OFDM transceiver. In this thesis project, a serial to parallel (S2P) converter, six FFT/IFFT architectures and parallel to serial (P2S) converter modules using fixed-point two's complement number system were implemented. The FFT uses an 18 bit fixed point representation for input/output data and memory coefficients. It is designed using radix-2 Decimation-In-Time (DIT) architecture. The implemented FFT architectures are differing with respect to RAM memory access, way of processing of the input samples, number of computational elements (butterflies) and memory storage requirements. The three realized implementation categories are: in-place computation, direct FFT computation and pipelined FFT computation. This report explains FFT architectures and methodologies to design, simulate and implement them on an FPGA device. This thesis report also presents area results in terms of FPGA resources and throughput results in terms of number of clock cycles for all the FFT architectures.

It’s widely known that microwaves can be a useful tool when it comes to heating many different kinds of materials. It’s much less known however that compared to regular convective heating it can exhibit catalytic properties. This project focuses on the difference between microwave heating and normal heating and its future in the field of solar cell manufacturing. The main purpose was to determine whether efficient DSSC could be manufactured by the use of microwaves. Focus was also put on the application for flexible polymers. Polymer sintering requires lower temperatures compared with the normally used substrates and they tend to have lower efficiencies. If the efficiencies can be raised these types of cells can become a cheap viable option by means of the so called roll-to-roll manufacturing. A clear improvement was seen in both efficiency and deviation when sintering by microwave heating compared to that of normal convective heating. Electrodes sintered by microwaves tend to show about double the performance in these cases. Another effect that was examined was the combined heating effect of TiO2 on conductive substrates. The combined heating of FTO and TiO2 can be about 30% higher than the additive heating. This is of course important from the perspective of manufacturing performance. Sintering a pure TiO2 paste by microwaves on a ITO:PEN substrate a DSSC efficiency of 5.5% was achieved which is a reasonably good result when compared with that of other polymer cells. Especially considering that this was a basic test. The electrode was only sintered for 2min and the paste was simple. This demonstrates that roll-to-roll printed DSSC is not a farfetched concept. Following that further work on similar cells are strongly encouraged. Some work was also put into creating solvothermally grown nanosheets combined with nanoparticles to create a hybrid cell in hopes of lowering electric resistivity and subsequently increasing overall solar cell performance. No real conclusions can be drawn in terms of increased performance. However there might be some indications of decreased losses but more time is needed on experimental work. The current results might however still prove valuable information for some readers.

Cloud computing has a huge importance and big impact nowadays on the IT world.The idea of community clouds has emerged recently in order to satisfy several user expectations. Clommunity is a European project that aims to provide a design and implementation of a self-congured, fully distributed, decentralized, scalable and robust cloud for a community of users across a commmunity network. One of the aspects to analyze in this design is which kind of Virtual Private Network (VPN) is going to beused to interconnect the nodes of the community members interested in access cloud services. In this thesis we will study, compare and analyze the possibility of using Tinc, IPOP or SDN-based solutions such as OpenFlow to establish such a VPN.

Bitcoin is a digital currency which is based on P2P network and open source software. It is avirtual currency without any control by any centralized organization. New Bitcoins are issuedby lots of specified algorithms. The whole Bitcoin network utilizes the distributed database toverify and record all the transactions through the nodes in the P2P network in which thedouble spending is prevented. No person or organization is able to control Bitcoin based on adecentralized P2P network and algorithm. The cryptographic functions of Bitcoin are designedto allow only the real Bitcoin owner to pay and transfer, and ensure the anonymity andmarketability.The purpose of this thesis is to analyze the security architecture and services for the Bitcoin system and describe of all the features and infrastructures of the whole Bitcoin network. A whole establishment demo including wallet client, mining server with GUI and mining client is implemented. Further improvement will be suggested and recommended for the system

Denna rapport behandlar analys och utveckling av ett ansökningssystem för miljömärkning åt Håll Sverige Rent, arbetet utfördes som examensarbete på KTH. I arbetet så identifieras hur ansökningsprocessen för miljömärkningen Green Key fungerar och hur den kan effektiviseras med hjälp av ett onlinebaserat ansökningssystem. Delar i ansökningsprocessen har kunnat automatiseras, andra delar har delats upp och organiserats för att underlätta ansökan för Håll Sverige Rents kunder. Resultatet har blivit ett komplett onlineansökningssystem som Håll Sverige Rent kan använda för att effektivisera deras nuvarande ansökningsprocess. / This paper is about a bachelor’s thesis and include an analysis and developed application processes for Keep Sweden Tidy. We have identified how the application process for the ecolabeling Green Key works today and how the process are made more efficient with the use of an online system. Parts of the process has been automate and other parts has been reorganized and restructured to make the application more user friendly for Keep Sweden Tidy’s customers. The result have been an online application system which Keep Sweden Tidy may use in order to make their current application process more efficient

Upphandlingar av affärssystem kan vara långdragna processer. Många av dessa upphandlingar och även implementationer kan misslyckas om inte involverade personer vet hur upphandlingen ska gå till från början till slut. Uppsatsen fokuserar på hela upphandlingsprocessen och hur den går till samt de kritiska framgångsfaktorer som bör has i åtanke vid upphandling av affärssystem. Syftet med uppsatsen är att intervjua olika parter som har olika synvinklar under upphandlingar för att kunna kartlägga upphandlingen och framgångsfaktorerna för en lyckad upphandlingsprocess. Dessa parter är upphandlingskonsult, kund och leverantör. Framgångsfaktorer, modeller och upphandlingar identifierades och beskrevs för att få en uppfattning om vad studien ska leta efter. Intervjuer gjordes sedan med två konsulter, en leverantör och en kund för att framställa och jämföra deras syn på faktorer och upphandlingar men även vilka egna framgångsfaktorer de kunde peka på utanför litteraturen. Författaren valde sedan att koncentrera den mängd material som kom ur intervjuerna för att göra analyser och dra slutsatser. Uppsatsen kunde då identifiera vissa framgångsfaktorer som de viktigaste och vissa som mindre viktiga. En del faktorer rådde det också stor variation på beroende på intervjuobjekt. Den kritiska framgångsfaktor som var den absolut viktigaste var förhållande till leverantör och kund. Vid beaktande av den och andra faktorer kan involverade personer i upphandlingar och projekt lyckas med chans till bättre resultat.

Over the last ten years, the demand for data has been increasing exponentially. To meet this demand, there are three ways to proceed: increasing the number of antennas, enhancing spectrum efficiency, enlarging bandwidths. This paper is focused on the last option, enlarging the bandwidth, and more precisely on the reuse or secondary use of frequencies through Licensed Shared Access and TV white spaces. This work aims at determining the potential development of these two new regulatory regimes and the potential impact on the telecom ecosystem and business.There is a common understanding of TVWS and regulators are implementing similar frameworks. The industry and regulators have launched plenty of trials and developed many standards. There are even some examples of commercial releases. However, the amount of channels available for TVWS activities is still uncertain since regulators have not stated their positions on the balancing between TVWS and digital dividend (refarming). Their decision will influence the market size and consequently the market take-up.Similarly to TVWS, national and international coherent regulatory frameworks are being developed around LSA. There is also a common view on uses among actors. Indoor coverage is one of the most mentioned uses. This will enhance the actors’ confidence in LSA, and might consequently increase investment. However, standardization is needed to bring the necessary economies of scale. The incumbents’ willingness to share their spectrums and the fees level are still unclear. These last parameters will have large impact on LSA take-up.The second part of the thesis tries to determine what ecosystems might develop. With TVWS, there are no licence fees or coverage requirements included in licence, which lowers the entrance barriers. This paper presents strategies where other players than MNOs provide connectivity. These strategies, which were built through group exercises done by Telecom workers, bring opportunities to these new connectivity providers and also values for its potential clients. Moreover, these new connectivity provider strategies possess real strengths and only limited weaknesses. However, the MNOs’ reluctance to support this new ecosystem is the most dangerous threat to its development.To a slightly lesser extent, LSA also lowers the entrance barriers into the connectivity-providing business. This is a game-changer for indoor coverage since LSA might enable the development of scenarios and ecosystems which were previously considered as hypothetical. Thus, scenario where a Managed Service Providers or a Network Equipment Providers offers connectivity (without MNOs) to a premise or a MVNO has the potential to take up. This strategy is valuable for connectivity providers and their clients. Here, financing this strategy is also a challenge, but the most important risk might arise from the MNOs’ pressures on the ecosystem’s actors to prevent this strategy from developing.