This thesis studies the Physical Layer (PHY) of the new IEEE 802.11acWireless Local Access Network (WLAN) standard. The 11ac is built basedon the 11n successful standard. The standard is expected to be completedby the end of 2013. And it promises a Very High Throughput (VHT),and robust communication. In order to achieve that, the 11ac uses morebandwidth, it employs higher numbers of Multiple-Input Multiple-Output(MIMO) spatial streams, and higher orders of modulations. The 11ac PHYframe structure is studied in details. The transmitter and receiver blocks areexplained and implemented by MATLAB. Bit Error Rate (BER) and ErrorVector Magnitude (EVM) simulations of the PHY were run. The effectof different Modulation and Coding Scheme (MCS), and bandwidths werestudied. The performance of MIMO and Space-Time Block Coding (STBC)was investigated. The simulation results shows how the 11ac benefits fromthe new employed features. The created MATLAB simulation program canbe used for further tests and research.

Performing optimization of structures is always of great interest. There are several different ways to optimize steel structures. Today, several companies are having difficulties with their cable drums during transport. Cable drums with full cable load become heavy and make it difficult to transport. This paper aims to examine existing published research and approaches, with a focus on steel optimization. This paper has two research objectives, the first one is to examine the possibilities for optimizing cable drums in terms of mass without compromising load capacity or yield stress. The second question is to determine how much of the weight/mass of cable drums may be reduced via optimization. To optimize it, measurements, cable drum modeling, research studies, and connecting suitable software's will be carried out in this paper. Participation Action Research and Reverse Engineering methodologies were implemented in combination. A literature review was performed to get a deeper understanding of the methods. A systematic literature review was done to identify available approaches and techniques for structural steel optimization. In order to optimize the cable drum, Excel and Autodesk Inventor were connected through Visual Basic Applications (VBA). The optimization process workflow acted with a server and two clients, where Excel acted as the server and Autodesk Inventor and MATLAB acted as clients. It was found that this was a suitable method for optimizing the cable drum were to work with an optimization process that included connecting a server with clients. The MATLAB function fmincon was applied with both interior-point algorithm and Sequential Quadratic Programming (SQP). The optimal design variables for the cable drum were established, and the objective minimization was accomplished by reducing the cable drum mass of 2495.20 kg. The cable drums mass was minimized to 101.86 kg. The literature review was systematically conducted to find available approaches and methods for structural steel optimization. The combination of Participatory Action Research (PAR) and Reverse Engineering (RE) was ideal for this project since it enabled both approaches to gather data on cable drum capacity and alternative optimization strategies.The schematic optimization workflow was appropriate to apply throughout the implementation phase. The workflow gave the user complete control over the optimization process, and the automated process saved time and was simple to adapt.

Recent advances in the field of computational intelligence have led to a numberof promising optimization algorithms. These algorithms have the potential to findoptimal or near-optimal solutions to complex problems within a reasonable timeframe. Structural optimization is a research field where such algorithms are appliedto optimally design structures. Although a significant amount of research has been published in the field ofstructural optimization since the 1960s, little of the research effort has been utilizedin structural design practice. One reason for this is that only a small portion ofthe research targets real-world applications. Therefore there is a need to conductresearch on cost optimization of realistic structures, particularly large structureswhere significant cost savings may be possible. To address this need, a software application for cost optimization of beam bridgeswas developed. The software application was limited to road bridges in concretethat are straight and has a constant width of the bridge deck. Several simplificationswere also made to limit the scope of the thesis. For instance, a rough design ofthe substructure was implemented, and the design of some structural parts wereneglected. This thesis introduces the subject of cost optimization, treats fundamentaloptimization theory, explains how the software application works, and presents acase study that was carried out to evaluate the application. The result of the case study suggests a potential for significant cost savings. Yet,the speeding up of the design process is perhaps the major benefit that should inclinedesigners to favor optimization. These findings mean that current optimizationalgorithms are robust enough to decrease the cost of beam bridges compared to aconventional design. However, the software application needs several improvementsbefore it can be used in a real design situation, which is a topic for future research. / Nya framsteg inom forskningen har lett till ett antal lovande optimeringsalgoritmer.Dessa algoritmer har potentialen att hitta optimala eller nästan optimala lösningartill komplexa problem inom rimlig tid. Strukturoptimering är ett forskningsområdedär dessa algoritmer tillämpas för att dimensionera konstruktioner på ett optimaltsätt. Även om en betydande mängd forskning har publicerats inom området strukturoptimeringsedan 1960-talet, så har endast lite av forskningsinsatserna kommit tillanvändning i praktiken. Ett skäl till detta är att endast en liten del av forskningenär inriktad mot verklighetsförankrade tillämpningar. Därför finns det ett behov avatt bedriva forskning på kostnadsoptimering av realistiska konstruktioner, särskiltstora konstruktioner där betydande kostnadsbesparingar kan vara möjligt. För att möta detta behov har ett datorprogram för kostnadsoptimering avbalkbroar utvecklats. Programmet begränsades till vägbroar i betong som är rakaoch har en konstant bredd. Flera förenklingar gjordes också för att begränsaomfattningen av arbetet. Till exempel implementerades en grov dimensionering avunderbyggnaden, och dimensioneringen av vissa komponenter försummades helt ochhållet. Detta examensarbete presenterar ämnet kostnadsoptimering, behandlar grundläggandeoptimeringsteori, förklarar hur programmet fungerar, och presenterar enfallstudie som genomfördes för att utvärdera programmet. Resultatet av fallstudien visar en potential för betydande kostnadsbesparingar.Trots det så är tidsbesparingarna i dimensioneringsprocessen kanske den störstafördelen som borde locka konstruktörer att använda optimering. Dessa upptäckterinnebär att aktuella optimeringsalgoritmer är tillräckligt robusta för att minskakostnaden för balkbroar jämfört med en konventionell dimensionering. Dock måsteprogrammet förbättras på flera punkter innan det kan användas i en verklig dimensioneringssituation,vilket är ett ämne för framtida forskning.

Today, the alloy content in steel scrap deliveries in Sweden are determined by the waste management company by test melts. Random sampling analysis (RSA) is an alternative method, under development, to determine the alloy composition of steel scrap. This method evaluates the alloy composition of the steel delivery based on a number of randomly chosen steel scrap unit. RSA is a surface analysis, it is done on a distributed area where with the help of a grid, marks the random steel scrap units for evaluation. This means that the surface fraction determines the odds of analyzing the steel scrap. In a previous study of RSA, 100 random pieces of scrap units was evaluated for its alloy composition with Optical Emission Spectroscopy (OES). These scrap deliveries were thereafter sent to an Electric Arc Furnace for melting. This was done to compare the RSA analysis with samples taken after scrap melting. The RSA study however assumes that the scrap units have the same weight. In this study, the weights of the scrap units in the RSA was assumed to have a variance. Using MATLAB® and the alloy composition data acquired from the old study, a simulation was made where 100 pieces and 100 analyses was made to see what the margin of error in comparison to the old study. Another goal with this study was to see if the variance of the weight had any relation to the absolute deviation of each element in the alloy composition. The results showed that there was no relation between the absolute deviation of each element and the weight distribution in the population. This indicates that there are other factors involved other than the weight distribution in the samples. The average margin of error for all the elements was calculated to 5.94% for the weight distribution of 0.1:0.1:10 kg. This indicates that RSA is accurate or close in analysis for old steel scrap deliveries even if the weight distribution is 0.1:0.1:10kg. The highest margin of error was obtained for W, Ce and Ti with a margin of error of 18.6%, 14.89% and 10.71% respectively. All the other elements had a margin of error beneath 10%. This indicates that for RSA on old steel scrap deliveries a margin of error of 10% would be a good benchmark on the accuracy of the analysis.

Nowadays, sleep disorders e.g. sleep apnea —the cessation of airflow at the nose and mouth lasting at least 10 second— are a broadly problem around the world. Direct and indirect costs associated to sleep problems are outsize and the quality of patient life is deteriorated because of it. In addition, Sleep is a fundamental part of everyday life, the lack of it or the poor quality of sleep may lead into the development of important diseases. Sleep studies are usually carried out by specialists by means of polysomnography. Polysomnography is a type of sleep study which is consisting of EEG, EOG, EMG, ECG, respiratory signals and/or many other biosignals which together can be used to determine the state of patient’s sleep and any other issue. Nowadays, visual inspection of these signals forms the “gold standard” in sleep clinics. The cost of monitoring a person overnight, the scarcity of beds available and the uncertainty of whether the results are representative of a normal nights’ sleep means that a move to home diagnostics is likely to be advantageous. Therefore, a necessity for home recorders systems capable of perform this kind of analysis has come out. A state machine based automatic scorer is developed and evaluated in Matlab by using 12 recordings of apnoeic patients from sleep heart health study (SHHS) database. By the analysis of EEG, EOG, EMG, Oxygen saturation (Sao2) and respiratory movements signals, the implemented algorithm is trained and evaluated to detect the five stages of subject’s sleep (Wake, N1, N2, N3, or REM) as well as apnoeic episodes according to guidelines from American Academy of Sleep Medicine (AASM). In the final evaluation of algorithms, the automatic scorer achieved 74±5.27% accuracy for all five stages and Cohen’s kappa of 0.5 for the overall set of 12 patients, being the accuracy better for healthier subjects and reaching in this case 78±4.05%. The analysis of the sleep apnea concluded with a sensitivity of 47.08%, a specificity of 83.38%, and an accuracy of 78.1%. Differences in the performance among patients according to their apnea/hypopnea index were significant.   Key Words: Polysomnography, AASM, Sleep apnea/hypopnea.

Elevated levels of geogenic arsenic (As) in groundwater are regarded as the most formidable environmental crisis in the contemporary world and an estimated 30-70 million people in Bangladesh are at risk. Many of the provided options for mitigation have not been well accepted. In recent years, local drillers have been targeting As-low groundwater on the basis of the color of the sediments. A correlation between the color characteristics of the sediments and the groundwater redox conditions and thereby the risk for As mobilization has been established. It is possible to assess the relative possibility of occurrence of high As concentrations in groundwater if the color characteristics of the sediments are known. One main objective of the present study is to validate if targeting As-safe groundwater is a sustainable mitigation strategy. This has been done through monitoring groundwater from tube-wells installed in sediments with different color, depth and redox characteristics. Samples were collected yearly from a set of 17 tube-wells for the period of 2004 to 2008 in Matlab, Bangladesh. The wells were grouped into oxidized and reduced/non-oxidized wells. All of these wells tap water within a depth of 85 m from the surface. Major cations and trace elements including As were analysed by high resolution ICP-OES; and anions were measured by ion chromatography. Groundwater chemistry of the water abstracted from different sediments revealed that no major change had occurred over the period of 5 years. In reduced wells, concentration of major cations and anions varied by <10% over time, and no significant variation was observed in redox sensitive elements, such as Fe, Mn and S. There were some minor variations in the As concentrations in the wells. In the oxidized wells, except well 58, major cations, anions and redox sensitive elements varied by <5%, while the As concentrations were found quite low and stable (<5.2 μg/L). Time series trends thus suggest that the change in groundwater chemistry is insignificant over the period of 5 years from 2004 to 2008. Low As concentrations in the tubewells installed in the oxidized brownish sediments thus validate the mitigation strategy corresponding to the conceptual understanding of the groundwater system in Matlab in southeastern Bangladesh.

UWB has the huge potential to impact the present communication systems due to its enormous available bandwidth, range/data rate trade-off, and potential for very low cost operation. According to FCC, Ultra Wideband (UWB) radio signal defined as a signal that occupies a bandwidth of 500 MHz or fractional bandwidth larger than 20% with strict limits on its power spectral density to -41.3dBm/MHz in the range 3.1GHz to 10.6GHz. Decades of research in the area of wide-band systems have lead us to new possibilities in the design of low power, low complexity radios, comparing with existing narrowband radio systems. In particular, impulse radio based ultra wideband (IR-UWB) is a promising solution for short-range radio communications such as low power radio-frequency identification (RFID), wireless sensor network's and wireless personal area network (WPAN) etc. Since a simple circuit, architecture adopted in the IR-UWB system, the non-idealities of receiver front end may lead to degrade the overall performance. Therefore, it is important to study these effects in order to create robust and efficient UWB system. However, majorities of recent studies are formed on the channel analysis, rather than the receiver system. The main objectives of this thesis work are, (a) System level modeling of non-coherent IR-UWB receiver, (b) Performance analysis of IR-UWB receiver with the help of bit error rate (BER) estimation, (c) A study on the impact of receiver front end non-idealities over BER, (d) Analysis of charge leakage in integrator and its effect on overall performance of UWB receiver. In this work, IR-UWB non-coherent energy detector receiver operating in the frequency band of 3GHz-5GHz based on the on-off keying (OOK) modulation was simulated in Matlab/Simulink. The effect of receiver front end non idealities and integrator charge leakages were discussed in detail with respect to overall performance of the receiver. The results show that non idealities and leakage degrade the performance as expected. In order to achieve a specific BER of 10-2 with the integrator leakage of 25%, the SNR should be increased by 2.1 dB compared to the SNR with no leakage at a data rate of 200Mbps. Finally, integrator design and its specifications were discussed.

A lot of people worldwide are affected by limitations and disabilities that make it hard to do even essential actions and everyday tasks, such as eating. The impact of robotics on the lives of elder people or people having any kind of inability, which makes it hard everyday actions as to eat, was considered. The aim of this thesis is to study the implementation of a robotic system in order to achieve an automatic feeding process. Different kinds of robots and solutions were taken into account, for instance, the Obi and the prototype realized by the Washington University. The system considered uses an RGBD camera, an Intel RealSense D400 series camera, to detect pieces of cutlery and food on a table and a robotic arm, an ABB-YuMi, to pick up the identified objects. The spoon detection is based on the pre-trained convolutional neural network AlexNet provided by MATLAB. Two detectors were implemented. The first one can detect up to four different objects (spoon, plate, fork and knife), the second one can detect only spoon and plate. Different algorithms based on morphology were tested in order to compute the pose of the objects detected. RobotStudio was used to establish a connection between MATLAB and the robot. The goal was to make the whole process as automated as possible. The neural network trained on two objects reached 100% of accuracy during the training test. The detector based on it was tested on the real system. It was possible to detect the spoon and the plate and to draw a good centered boundary box. The accuracy reached can be considered satisfying since it has been possible to grasp a spoon using the YuMi based on a picture of the table. It was noticed that the lighting condition is the key factor to get a satisfying result or to miss the detection of the spoon. The best result was archived when the light is uniform and there are no reflections and shadows on the objects. The pictures which get a better result for the detection were taken in an apartment. Despite the limitations of the interface between MATLAB and the controller of the YuMi, a good level of automation was reached. The influence of lighting conditions in this setting was discussed and some practical suggestions and considerations were made. / No

Die Substituierung konventionell angetriebener Kleinkehrmaschinen (KKM) durch elektrisch betriebene Äquivalente, kann zu einer Verbesserung der Luft- und Lebensqualität insbesondere in Ballungszentren führen. Dabei sind nicht nur die lokal CO2-neutrale Fortbewegung entscheidend, sondern auch Maßnahmen zur Geräuschminimierung. Diese Arbeit stellt Lösungsansätze vor und wählt aus verschiedenen Konzepten eine Vorzugsvariante aus, die im Anschluss realisiert und untersucht wird. Dabei werden zunächst messtechnische Untersuchungen an ausgewählten KKM durchgeführt, die im Weitern dafür verwendet werden eine Konzeptauswahl zu treffen. Aus den gewonnen Datensätzen werden u. a. ein Analysetool zur routen- und situationsabhängigen Energieverbrauchsermittlung sowie eine Ganzfahrzeugsimulation erstellt. Das realisierte Labormusterfahrzeug wird zur Validierung der Ganzfahrzeugsimulation und als „Proof of Concept“ verwendet, um entsprechende Annahmen zur Verbrauchsreduzierung nachzuweisen. Die vorliegende Dissertation liefert damit einen Beitrag zur Emissionsreduzierung und Dekarbonisierung, speziell in dicht besiedelten Großstädten. Kern der Arbeit ist die Untersuchung der Elektrifizierung von Kleinkehrmaschinen und der damit einhergehenden erwartbaren Emissionsminderung. Dabei werden u. a. folgende Forschungsfragen beantwortet: • Wie können Kleinkehrmaschinen (KKM) wissenschaftlich untersucht und miteinander verglichen werden? • Wie kann eine KKM verbessert/angepasst/optimiert werden, um Emissionen zu reduzieren und somit Schadstoffe für Mensch und Tier sowie Treibhausgase zu minimieren? • Können verbrennungskraftbetriebene Kleinkehrmaschinen (VK-KKM) durch elektrische Kleinkehrmaschinen (E-KKM) substituiert werden?

Heat shrink tubing is used to insulate wire conductors, protect wires, and to create cable entry seals in wire harnessing industries. Performing this sensitive process manually is time consuming, the results are strongly dependent on the operator’s expertise, and the process presents safety concerns. Alternatively, automating the process minimizes the operators’ direct interaction, decreases the production cost over the long term, and improves quantitative and qualitative production indicators dramatically. This thesis introduces the automation of a heat shrink tubing prototype machine that benefits the wire harnessing industry. The prototype consists of an instrumented heat chamber on a linear positioning system, and is fitted with two heat guns. The chamber design allows for the directing of hot air from the heat guns onto the wire harness uniformly through radially-distributed channels. The linear positioning system is designed to move the heat chamber along the wire harness as the proper shrinkage temperature level is reached. Heat exposure time as a major factor in the heat shrink tubing process can be governed by controlling the linear speed of the heat chamber. A control unit manages the actuator position continuously by measuring the chamber’s speed and temperature. A model-based design approach is followed to design and test the controller, and MATLAB/Simulink is used as the simulation environment. A programmable logic controller is selected as the controller implementation platform. The control unit performance is examined and its responses follow the simulation results with adequate accuracy.