No description available.

One method to increase efficiency, robustness and accuracy of automatic control, is to introduce mathematical models of the system in question to increase performance. With these models, it is possible to predict the behavior of the system, which enables control according to the predictions. The problem here is that if these models do not describe the dynamics of the system well enough, this method could fail to increase performance. To address this problem, one idea is to estimate the dynamics of the system during operation, using methods for system identification, signal processing and sensor fusion. In this thesis, the possibilities of estimating a ship's dynamics during operation have been investigated. The mathematical model describing the dynamics of the ship is a graybox model, which is based on the physical and mechanical relations. This model's properties are therefore described by physical quantities such as mass and moment of inertia, all of which are unknown. This means that, when estimating the model, these physical properties will be estimated. For a systematic approach, first a simulation environment with a 4-degrees-of-freedom ship model has been developed. This environment has been used for validation of system identification methods. A model of a podded propulsion system has also been derived and validated. The methods for estimating the properties of the ship have been analyzed using the data collected from the simulations. For system identification and estimation of ship properties, the influence of measurement noise and potential of detecting a change in dynamics has been analyzed. This has been done through Monte Carlo simulations of the estimation method with different noise realizations in the simulations, to analyze how the measurement noise affects the variance and bias for the estimates. The results show that variance and bias vary a lot between the parameters and that even a small change in dynamics is visible in some parameter estimates when only ten minutes of data have been used. A method based on cumulative summation (CUSUM) has been proposed and validated to analyze if such a method could yield fast and effective detection of system deviations. The results show that the method is rather effective a with robust detection of changes in the dynamics after about four minutes of data collection. Finally, the methods have been validated on data collected on a real ship to analyze the potential of the methods under actual circumstances. The results show that the particular data is not appropriate for this kind of application along with some additional problems that can yield impaired results. / Genom att inkludera matematiska modeller som beskriver ett systems dynamik i styrningsalgoritmer, kan man åstadkomma en automatisk styrning med förbättrad effektivitet, robusthet och noggrannhet. Med dessa modeller går det att förutsäga beteendet hos systemet och därmed öppnas också möjligheten att använda sig av detta i styrningen. Problemet är att om dessa modeller inte beskriver systemets dynamik tillräckligt bra kan prestandan istället sänkas genom dessa metoder. Den här sortens problem kan man lösa genom att aktivt skatta systemets dynamik under körning, med hjälp av metoder för systemidentifiering, signalbehandling och sensorfusion. I denna exjobbsrapport har möjligheterna att skatta ett skepps girdynamik undersökts. Den matematiska modell som beskriver skeppets dynamik är en grålådemodell som baserar sig på fysikaliska och mekaniska samband. Denna modells egenskaper beskrivs därför av fysikaliska storheter så som massa, tröghetsmoment och tyngdpunkt, vilka alla är okända. Detta innebär att vid modellskattning skattas dessa fysikaliska storheter, vilka kan vara av stort intresse. En simuleringsmiljö med en skeppsmodell med fyra frihetsgrader har skapats och använts för att validera metoder för systemidentifiering. En modell av ett roterbart framdrivningssystem har också härletts och inkluderats i simuleringsmodellen. Vid systemidentifiering och skattning av skeppets egenskaper har dels inverkan av mätbrus analyserats samt även möjligheter till att detektera skillnader i dynamik. Detta har gjorts med Monte Carlo-simuleringar av skattningsmetoden med olika brusrealiseringar för att analysera hur mätbrus påverkar variansen och metodfelet hos skattningarna. Resultaten visar att vissa parametrar skattas med större noggrannhet och hos dessa kan därmed en förändring i dynamik identifieras när endast tio minuter av data har använts. En metod baserad på kumulativ summering av residualer har formulerats och validerats, detta för att undersöka om en sådan metod kan ge snabb och effektiv detektion av systemförändringar. Resultat visar på robusthet i att detektera skillnader i dynamik efter ungefär fyra minuter av datainsamling. Slutligen har metoderna validerats på data insamlad på ett riktigt skepp för att undersöka potentialen under verkliga omständigheter. Resultaten visar att just denna data inte är lämplig för denna applikation samt några problem som kan leda till försämrade resultat.

<p>The examination has been performed at Bjerking AB, which is an architectural and engineering company. Bjerking AB has the ambition to be a member of Green Building.</p><p>The Green Building program developed in year 2005 by The European Commission, the program is an environmental system with the aim to improving energy efficiency within the sectors of non-residential buildings. The minimum requirements to participate the program are following: in new-built buildings the calculated energy consumption must be 25 % lower than the requirements in the BBR (Building regulations) and in refurbishment the reduction must be 25 % lower than before the optimization.</p><p>The aim of this study has been to examine and review the company Bjerking AB's energy efficiency work in the project of building the school/kindergarten S:ta Maria Alsike, where the goal is to get this building Green Building classed. A description of requirements to become a member of the Green Building has also accomplished in the thesis.</p><p>The methods performed in this study are literature review, searches on the Internet, studies on the project database for facts/values, calculation of energy consumption and interviews of members of the Green Building. </p><p>The following issues have been dealt with in the report;</p><p>-          Did the building in the project manage the requirement to achieve an   energy consumption that is 25% lower than the requirements in BBR?</p><p>-          What technical measures/system was selected in the building?</p><p>-          What kind of cooperation was the project based on?</p><p>-          What is required for consultancy companies and real estate owners to become members of the Green Building?</p><p>The study of the project and calculation of estimated energy consumption in the building, give the result 47 kWh/m², year. This is 60 % lower than the requirements of BBR. The Green Building requirement is that the building's energy consumption should be at least 25% less than the requirements in BBR. The building fulfills this requirement by a significant margin. It can therefore be concluded that the technical solutions carried out in the building are energy efficient. The project consisted of the cooperation shape “partnering ", which can be assumed to be a good form of cooperation in order to achieve an energy efficient building. The consultancy company Bjerking AB and the landlord Knivsta Pastorat has the potential to become members of Green Building, as Green Building Endorser respective Green Building Partner.</p><p><strong>Keywords:</strong> energy efficiency, requirements of BBR, technical systems, cooperation, consultancy companies, real estate owners, estimated energy consumption, partnering, Green Building Partner, Green Building Endorser.</p> / Utbildningsprogram: Civilingenjör i samhällsteknik, 180 p (270 hp).

In this paper, we analyze the achievable secrecy rates in the two-hop wiretap channel with four nodes, where the transmitter and the receiver have multiple antennas while the relay and the eavesdropper have only a single antenna each. The relay is operating in amplify-and-forward mode and all the channels between the nodes are known perfectly by the transmitter. We discuss different transmission and protection schemes like artificial noise (AN). Furthermore, we introduce interference neutralization (IN) as a new protection scheme. We compare the different schemes regarding the high-SNR slope and the high-SNR power offset and illustrate the performance by simulation results. It is shown analytically as well as by numerical simulations that the high SNR performance of the proposed IN scheme is better than the one of AN.

1-bit analog-to-digital conversion is very attractive for low-complexity communications receivers. A major drawback is, however, the small spectral efficiency when sampling at symbol rate. This can be improved through oversampling by exploiting the signal distortion caused by the transmission channel. This paper analyzes the achievable data rate of band-limited communications channels that are subject to additive noise and inter-symbol-interference with 1-bit quantization and oversampling at the receiver. It is shown that not only the channel noise but also the inter-symbol-interference can be exploited to benefit from oversampling.

Sound criteria for partial order reduction for probabilistic concurrent systems have been presented in the literature. Their realization relies on a depth-first search-based approach for generating the reduced model. The drawback of this dynamic approach is that it can hardly be combined with other techniques to tackle the state explosion problem, e.g., symbolic probabilistic model checking with multi-terminal variants of binary decision diagrams. Following the approach presented by Kurshan et al. for non-probabilistic systems, we study partial order reduction techniques for probabilistic concurrent systems that can be realized by a static analysis. The idea is to inject the reduction criteria into the control flow graphs of the processes of the system to be analyzed. We provide the theoretical foundations of static partial order reduction for probabilistic concurrent systems and present algorithms to realize them. Finally, we report on some experimental results.

The examination has been performed at Bjerking AB, which is an architectural and engineering company. Bjerking AB has the ambition to be a member of Green Building. The Green Building program developed in year 2005 by The European Commission, the program is an environmental system with the aim to improving energy efficiency within the sectors of non-residential buildings. The minimum requirements to participate the program are following: in new-built buildings the calculated energy consumption must be 25 % lower than the requirements in the BBR (Building regulations) and in refurbishment the reduction must be 25 % lower than before the optimization. The aim of this study has been to examine and review the company Bjerking AB's energy efficiency work in the project of building the school/kindergarten S:ta Maria Alsike, where the goal is to get this building Green Building classed. A description of requirements to become a member of the Green Building has also accomplished in the thesis. The methods performed in this study are literature review, searches on the Internet, studies on the project database for facts/values, calculation of energy consumption and interviews of members of the Green Building.  The following issues have been dealt with in the report; -          Did the building in the project manage the requirement to achieve an   energy consumption that is 25% lower than the requirements in BBR? -          What technical measures/system was selected in the building? -          What kind of cooperation was the project based on? -          What is required for consultancy companies and real estate owners to become members of the Green Building? The study of the project and calculation of estimated energy consumption in the building, give the result 47 kWh/m2, year. This is 60 % lower than the requirements of BBR. The Green Building requirement is that the building's energy consumption should be at least 25% less than the requirements in BBR. The building fulfills this requirement by a significant margin. It can therefore be concluded that the technical solutions carried out in the building are energy efficient. The project consisted of the cooperation shape “partnering ", which can be assumed to be a good form of cooperation in order to achieve an energy efficient building. The consultancy company Bjerking AB and the landlord Knivsta Pastorat has the potential to become members of Green Building, as Green Building Endorser respective Green Building Partner. Keywords: energy efficiency, requirements of BBR, technical systems, cooperation, consultancy companies, real estate owners, estimated energy consumption, partnering, Green Building Partner, Green Building Endorser. / Utbildningsprogram: Civilingenjör i samhällsteknik, 180 p (270 hp).

In heterogeneous dense networks where spectrum is shared, users privacy remains one of the major challenges. When the receivers are not only interested in their own signals but also in eavesdropping other users' signals, the cross talk becomes information leakage.We propose a novel and efficient secrecy rate enhancing relay strategy EFFIN for information leakage neutralization. The relay matrix is chosen such that the effective leakage channel (spectral and spatial) is zero. Thus, it ensures secrecy regardless of receive processing employed at eavesdroppers and does not rely on wiretaps codes to ensure secrecy, unlike other physical layer security techniques such as artificial noise. EFFIN achieves a higher sum secrecy rate over several state-of-the-art baseline methods.

In heterogeneous dense networks where spectrum is shared, users' privacy remains one of the major challenges. On a multi-antenna relay-assisted multi-carrier interference channel, each user shares the spectral and spatial resources with all other users. When the receivers are not only interested in their own signals but also in eavesdropping other users' signals, the cross talk on the spectral and spatial channels becomes information leakage. In this paper, we propose a novel secrecy rate enhancing relay strategy that utilizes both spectral and spatial resources, termed as information leakage neutralization. To this end, the relay matrix is chosen such that the effective channel from the transmitter to the colluding eavesdropper is equal to the negative of the effective channel over the relay to the colluding eavesdropper and thus the information leakage to zero. Interestingly, the optimal relay matrix in general is not block-diagonal which encourages users' encoding over the frequency channels. We proposed two information leakage neutralization strategies, namely efficient information leakage neutralization (EFFIN) and local-optimized information leakage neutralization (LOPTIN). EFFIN provides a simple and efficient design of relay processing matrix and precoding matrices at the transmitters in the scenario of limited power and computational resources. LOPTIN, despite its higher complexity, provides a better sum secrecy rate performance by optimizing the relay processing matrix and the precoding matrices jointly. The proposed methods are shown to improve the sum secrecy rates over several state-of-the-art baseline methods.

Klimatförändringarna blir allt mer omfattande i takt med att jordens befolkning ökar. Den negativa miljöpåverkan bottnar till stor del i användandet av råvaror och energiförbrukning vid skapandet av materiella ting. Enligt energimyndigheten (2015) står byggsektorn för ca 40 % av Sveriges totala energianvändning. För att minska energianvändningen har mål både på nationell och internationell nivå skapats. Målen är tänkta att skapa större förståelse av ett mer energieffektivt byggt samhälle för samtliga aktörer inom byggbranschen. En hållbar utveckling av husbyggandet kräver förutom att värna om miljön en beaktning av de ekonomiska och sociala aspekterna.   I det här examensarbetet har det undersökts om två specifika standardhus från en småhusleverantör kan utvecklas till passivhus med bevarad arkitektonisk karaktär. Studien syftar delvis till att undersöka om begreppet passivhus kan fungera som ett hållbart koncept för byggandet av enfamiljshus. Begreppet hållbar utveckling har begränsats och en förenkling har applicerats i arbetet. Den ekologiska aspekten representeras av energiberäkningar och eventuella åtgärder för att standardhusen ska uppnå kraven för passivhus. Den ekonomiska aspekten representeras av en livscykelkostnadsanalys med hjälp av nuvärdesmetoden och återbetalningsmetoden. Den sociala aspekten representeras av en utvärdering av förändring i boendekvaliteter vid utveckling från ett standardhus till passivhus. Studien presenterar även en alternativ utformning av ett passivhus med avsikt att främja positiva boendekvaliteterna.   Standardhusen tillhör en småhusproducent, Intressanta hus, som har sitt huvudsäte i Västerås. Husen utgörs av en villa på 147 m2 i ett plan med pulpettak samt en villa på 151 m2 i två plan med sadeltak. Med anledning av Intressanta hus geografiska läge har Västerås klimat använts som utgångspunkt vid energiberäkningarna. För att addera ytterligare en utmaning har även möjligheter för utveckling till passivhus undersökts för standardhusen i ett subarktiskt klimat i Kiruna. Västerås representerar därmed klimatzon III och Kiruna klimatzon I.   Resultaten avslöjade att det är möjligt att utveckla standardhuset i två plan med sadeltak till passivhus och samtidigt bevara den arkitektoniska karaktären i de båda klimatzonerna. Standardhuset med ett plan och pulpettak är endast möjligt att anpassa till passivhus i klimatzon III med bevarad arkitektonisk karaktär. Livscykelkostnadsanalysen visar med hjälp av nuvärdesmetoden att det är ekonomiskt fördelaktigt att investera i passivhus som ett koncept för en kalkylperiod på 50 år. Den boendekvalitet som främst förändras är bostadens ljusinsläpp och för passivhuset i ett plan är skillnaden av ljusinsläpp markant i klimatzon I.   Studiens slutsats är att konceptet passivhus är en metod av husbyggnation som främjar den hållarbara utvecklingen i förenklad form. Resultaten är framförallt positiva för klimatzon III men om byggnaden har låg formfaktor kan konceptet fungera bra även i kallare klimat som återfinns i klimatzon I. / The climate changes increases as the population increases. The negative environmental impact is mostly based on the use of raw materials and energy consumption in the production of various products. According to Energimyndigheten (2015), the building sector is the cause of about 40 % of Sweden's total energy use. In order to reduce the energy use goals have been created at both national and international levels. The goals are intended to create a greater understanding of a more energy efficient society for all actors within the construction industry. In addition to create a sustainable development of the building sector one needs to also take in account the social and economic aspects.   This master thesis examined whether two specific standard houses from a small house producer can be adapted to passive houses with a preserved architectural character. The purpose of the study is partly to investigate whether the concept of passive houses can serve as a sustainable concept of building single family houses. The concept of sustainable development has been simplified. The ecological aspect is represented by the energy calculations and possible actions that the standard houses need to achieve in order to meet the requirements for passive houses. The economic aspect is represented by a life cycle cost analysis using the Net Present Value method and the Simple Payback method. The social aspect is represented by an evaluation of changes in living qualities as the standard houses develops to passive houses. The study also presents an alternative design of a passive house with the purpose of improving the accommodation qualities.   The standard houses belong to a small-house-producer, Intressanta hus, who has their main market in Västerås. The houses is represented by a 147m2 villa with one floor and a pulpit roof and a 151m2 villa with two floors and a pitched roof. Due to Intressanta hus geographic location, the typical climate for Västerås has been used in the energy calculations. To add another dimension, opportunities for developing the standard houses to passive houses have also been investigated for the typical climate in Kiruna. Therefore Västerås represents climate zone III and Kiruna represents climate zone I.   The results revealed that it is possible to adapt the standard house with two floors and a pitched roof to a passive house while preserving the architectural character in both climate zones. The standard house with one floor and a pulpit roof is only possible to adjust to a passive house in climate zone III with a preserved architectural character. The life cycle cost analysis using the Net Present Value showed that it is an economical advantage to invest in a passive house in a period of 50 years. The accommodation quality that changes the most is the incident light in the houses and for the passive house with one floor the difference of light is remarkably high in climate zone I.