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  • 1.
    Alterbeck, Jonas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper.
    Förbrukningsreduktion: Ett alternativ till gasturbiner som snabb aktiv störningsreserv?2014Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    The gas turbines in the Swedish secondary reserve are reaching the end of their technical lifetime, hence alternative solutions need to be considered. One of the solutions thought to have the greatest potential is the use of so called consumptionreduction. By entering contracts with large consumers, agreements are made to reduce consumption in the event of major disturbances in the power system and thus being used as a secondary reserve. This thesis investigates the feasibility of consumption reduction as part of the secondary reserve. This has been achieved by developing a requirement specification for the disturbance reserve and by studying the technical and economic potential for consumption reduction among a range of consumers.The technical potential for consumption reduction that fulfils the requirements for participating in the secondary reserve are on average 750 MW in SE 3 and 98 MW in SE 4. The result of this study shows that consumption reduction could work as a supplement to the gas turbines, but could not entirely replace the current solution. Furthermore, replacing the gas turbines would cause loss of features such as black start and automatic frequency regulation. Nevertheless, consumption reduction is considered as a workable solution for the disturbance reserve that is both cheaper and more environmentally friendly. Before launching consumption reduction as a reserve, a market model has to be developed, taking the findings of this thesis into account: high electricity prices have negative effect on availability and that low liquidity on the market causes short endurance.

  • 2.
    Amanda, Nordhamn
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Design and implementation of a demonstrator for a Bluetooth Low Energy based fleet service system for hand-held gardening and forestry products2016Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Today, large companies specialized in forestry or park maintenance may own very large machine fleets consisting of hundreds of trimmers, chainsaws and brush cutters. Husqvarna Group, whose core business lies within high-end forestry and gardening products, has noticed that such companies tend to buy cheaper, low quality forestry and gardening products. The reason is thought to be that the companies lack a proper overview of the service status and utilization levels of their machines, leading to insufficient service, causing machines to break prematurely and making it hard to motivate investments in more expensive products. Hence, the companies usually adopt a consumerist approach, and buy cheaper products that are thrown away upon breaking.

    To make their products more attractive to machine park owners, Husqvarna want to explore the area of Internet of Things and equip their machines with sensing and communication capabilities. Collected data could be used to provide an overview of machine usage and service requirements to the machine parks owners, and could make it easier for machine park owners to dimension their machine fleet. In addition to this, a machine monitoring system where specific operator behavior can be tracked could enable identification of operators who consistently mistreat their machines by, for example, running the machine engine at non-optimal rotation speeds.

    In this master's thesis, a demonstrator of the working principle of a Bluetooth Low Energy based Fleet Service System is designed and implemented, complete with an evaluation of if received signal strength indicator (RSSI) is a good enough distance estimator to determine which operator operates a certain machine. 

    Experiments carried out indicate that while RSSI is not a good estimator of distance, it could be used to determine the operator in closest proximity given that operators are not allowed to work closer than within a 10 m radius of each other.

  • 3. Ask, Simon
    et al.
    Lindh, Rickard
    Design och konstruktion av roterande LiDAR-system för 360 graders objektdetektering2017Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    Although laser rangefinder technologies have been around for decades in military, cartography, building, industrial and research applications it is only in recent years that more generally applicable and cheaper consumer grade laser range finder sensors have become available. This project investigates the possibilities and limitations of creating a mobile 360 degree, two-dimensional obstacle detection system using off-the-shelf available electronic components.

    Using a Lidar Lite 3 from Garmin Ltd., an Arduino compatible microcontroller based on Atmel 328P, a Raspberry Pi 3 from The Raspberry Pi Foundation and an electronic speed controlled brushless DC motor driving the rotation, it is shown how range data measurements can be collected, communicated, processed and displayed at measurement rates between 500 and 1000 Hz. At 5 Hz update rate of a complete 360-degree data set, this translates to a worst case angular resolution of 2.5 degrees at ranges reaching 10 meters depending on target reflectivity. Configured for these faster measurement rates, at static measurements of a white painted wall, the measurements show a standard deviation of 0.06 m at a five-meter range, going up to 0.19 m at a range of 10 meters.

    A modular and mobile prototype was designed and built. The modularity allowed testing and verification of two configurations. Configuration A uses a slip ring for power and data transfer to the rotating sensor. Configuration B allows the laser range finder to be stationary and instead rotates a first surface aluminum mirror positioned at 45 degrees above the sensor.

    The measurement results show that increasing range has a notable adversely effect on the number of successful readings in a setting demanding faster measurement rates of above 500 Hz. The number of successful readings decreases at ranges above 5 meters, and this decrease of successful readings is more pronounced in the configuration using a mirror to reflect the measurement. The mirror reflected version does on the other hand allow an electromechanically simpler, more silent and durable system.

    Using a density based clustering algorithm it is shown how person sized objects in the point cloud data can be robustly detected at ranges up to 5 meters. 

  • 4.
    Axer, Philip
    et al.
    Technical University Braunschweig.
    Ernst, Rolf
    Technical University Braunschweig.
    Falk, Heiko
    Ulm University.
    Girault, Alain
    INRIA Grenoble Rhône-Alpes.
    Grund, Daniel
    Saarland University.
    Guan, Nan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Jonsson, Bengt
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Marwedel, Peter
    Technical University Dortmund.
    Reineke, Jan
    Saarland University.
    Rochange, Christine
    University of Toulouse.
    Sebastian, Maurice
    Technical University Braunschweig.
    von Hanxleden, Reinhard
    Christian-Albrechts-Universität zu Kiel.
    Wilhelm, Reinhard
    Saarland University.
    Yi, Wang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Building timing predictable embedded systems2014Inngår i: ACM Transactions on Embedded Computing Systems, ISSN 1539-9087, E-ISSN 1558-3465, Vol. 13, nr 4, s. 82:1-37Artikkel i tidsskrift (Fagfellevurdert)
  • 5.
    Berglund, Joel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    Measurements and analysis of UDP transmissions over wireless networks2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    The growth and expansion of modern society rely heavily upon well-functioning data communication over the internet. This phenomenon is seen at the company Net Insight where the need for transferring a large amount of data in the form of media over the internet in an effective manner is a high priority. At the moment most internet traffic in the modern world is done by the use of the internet protocol TCP (Transmission Control Protocol) instead of the simpler protocol UDP (User Datagram Protocol). Although TCP works in an excellent manner for most kinds of data communication it seems that this might not always be the case, so the use of UDP might be the better option in some occurrences. It is therefore of high interest at Net Insight to see how different types of wireless networks behave under different network circumstances when data is sent in different ways through the use of UDP. Thereby this report focuses on the measurement and analysis of how different wireless networks, specifically 4G, 5.0 GHz and 2.4 GHz WLAN networks, behaves when exposed to varied network environments where data is transmitted by the use of UDP in different ways. To perform a network-analysis data is collected, processed, and then analyzed. This network-analysis resulted in many conclusions regarding network behavior and performance for the different wireless networks.

  • 6. Bi, Yin
    et al.
    Lv, Mingsong
    Song, Chen
    Xu, Wenyao
    Guan, Nan
    Yi, Wang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    AutoDietary: A wearable acoustic sensor system for food intake recognition in daily life2016Inngår i: IEEE Sensors Journal, ISSN 1530-437X, E-ISSN 1558-1748, Vol. 16, nr 3, s. 806-816Artikkel i tidsskrift (Fagfellevurdert)
  • 7.
    Bjervig, Joel
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Slagbrand, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Thermal Imaging Platform for Drones: Cost-effective localization of forest fires2019Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    A device for identifying forest fires in an early stage has been developed during the course of this project. Attached to a drone, this prototype will provide a live-stream to a web server displaying a blended frame, made of a thermographic image showing thermal radiation and a regular photography with the visible light. The platform consists of a small single-boarded computer, a thermal camera sensor and a regular camera module. All powered by a power bank and fitted into a custom made 3D printed plastic case. At startup the computer automatically executes scripts written in Python, initializing its sensor components and processes the captured images which finally gets transmitted to a live-stream via a web server connection. Everything described above worked well, but originally the intent was for the web interface to provide a map with the current location coordinates of the drone. Since a module for mobile communication with support for GPS was not acquired, any implementation of such kind was impossible. However, several drone models already possess the feature to obtain such coordinates.

  • 8.
    Björkelund de Faire, Elias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektricitetslära.
    Implementering av mjukvarubaserat PLC-system för reglering av magnetiseringen av en synkrongenerator2011Independent thesis Basic level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    In order to reduce the price for, and improve the performance of automatic control systems for magnetization of synchronus generators, the possibilities of using a PC based software PLC system, Programmable Logic Controller, has been investigated. The result is a system based on the CoDeSys software PLC with runtime environment from 3S-Software, communicating with external units via Modbus fieldbus. System price is reduced from €5000 to €2000 and system processing speed is reduced from 10 ms for a Siemens S7 PLC to 4 ms with the CoDeSys PLC system though unsolved problems with runtime seizure caused by improper settings in the PC BIOS.

  • 9.
    Bodin, Emanuel
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Frisberg, Olle
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Ström, Matilda
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Sensormolnet: Trådlös övervakning av växter.2017Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Målsättningen med projektet var att utforma ett smart system förjordfuktsmätning innehållandes sensorer, datalagring samt visuellpresentation av mätdata i en applikation. Lagringen sker på enwebbserver i en databas och presentationen i form av en applikationför Android samt en webbsida. Resultatet blev en lyckad slutprodukt iform av en kapacitiv sensor tillverkad av laminerat kopparfolie sommed en mikrodator av typ ESP8266 skickar data via WiFi tillwebbservern. Databasen som lagrar datan är skapad i MySQL ochdatabaskommunikationen har skrivits i PHP. Förutom att visualiseramätdata kan applikationen och webbsidan kommunicera med ESPn samtskicka notiser till användaren i form av push-notifikationer då växten behöver vattnas.

    En slutsats från projektet är att sensorer för jordfuktsmätningrelativt enkelt kan skapas från lättillgängligt material och att ettsmart system kan utvecklas med få och billiga komponenter. En annanslutsats är att vid utveckling av en produkt som består av fleraprocesser som ska samverka tillsammans finns stor risk att oväntadefel uppstår. Ska en produkt vara kommersiellt gångbar krävs en långtid av betatestning för att vara säker på att produkten inteinnehåller brister.

  • 10.
    Bondesson, Carl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    Modelling of Safety Concepts for Autonomous Vehicles using Semi-Markov Models2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Autonomous vehicles is soon a reality in the every-day life. Though before it is used commercially the vehicles need to be proven safe. The current standard for functional safety on roads, ISO 26262, does not include autonomous vehicles at the moment, which is why in this project an approach using semi-Markov models is used to assess safety. A semi-Markov process is a stochastic process modelled by a state space model where the transitions between the states of the model can be arbitrarily distributed. The approach is realized as a MATLAB tool where the user can use a steady-state based analysis called a Loss and Risk based measure of safety to assess safety. The tool works and can assess safety of semi-Markov systems as long as they are irreducible and positive recurrent. For systems that fulfill these properties, it is possible to draw conclusions about the safety of the system through a risk analysis and also about which autonomous driving level the system is in through a sensitivity analysis. The developed tool, or the approach with the semi-Markov model, might be a good complement to ISO 26262.

  • 11.
    Carlos, Pérez Penichet
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Hermans, Frederik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Voigt, Thiemo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    On Limits of Constructive Interference in Backscatter Systems2017Inngår i: Global Internet of Things Summit (GIoTS), 2017, IEEE, 2017, s. 178-182Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Backscatter communication reduces the energy consumption of resource-constrained sensors and actuators by several orders of magnitude as it avoids the resource-consuming need to generate a radio wave. Many backscatter systems and applications suffer from low communication range. By exploiting the collective power of several tags that transmit the same data simultaneously, constructive interference may help to remedy this problem and increase the communication range. When several tags backscatter the same signal simultaneously it is not necessarily true that constructive interference occurs. As our theoretical results and previous work indicate the interference might also be destructive. Our experimental results on real hardware suggest that exploiting constructive interference to increase the communication range requires careful coordination which is difficult in decentralized settings.

  • 12.
    Dancila, Dragos
    IMEC/SSET, B-3001 Leuven, Belgium; UCL/EMIC, B-1348 Louvain-la-Neuve, Belgium.
    A 60 GHz silicon micromachined cavity resonator with integrated tuning MEMS array2009Konferansepaper (Fagfellevurdert)
  • 13.
    Dancila, Dragos
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    A microfabricated sensor and a method of detecting a component in bodily fluid2015Patent (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    The invention relates to a microfabricated sensor (1 ) for detecting a component in bodily fluid, comprising; an inlet means (2) for receiving a sample of bodily fluid, a fluid cavity (6) connected to the inlet means for receiving the sample of bodily fluid from the inlet means, and an RF resonant cavity (13), delimited by walls (14). At least one of the walls forms a separating wall (15), separating the fluid cavity from the RF resonant cavity, wherein the separating wall is configured such that the dielectric properties of the bodily fluid in the fluid cavity provide an influence on the electromagnetic properties of the RF resonant cavity.

  • 14.
    Dancila, Dragos
    Universite catholique de Louvain (UCL).
    MM-wave integrated RF-MEMS tunable cavity resonators, filters and ultra-low phase-noise oscillators2011Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    Within the Microelectronics Industry, the core research is focused on the realization of the Moore's law, which states that circuit density doubles every 24 months, shaping the framework of the More of Moore paradigm. However, Moore's law is expected to end, as devices are reaching limitations inherent to the approach of the atomical dimensions. Alternative research paths emerged, forming the new More than Moore paradigm. This consists in using the microfabrication technological knowhow towards the realization of alternative devices and applications, among others the miniaturization and integration of Radio Frequency (RF) devices by Micro Electromechanical Systems (MEMS), i.e. RF-MEMS. The RF-MEMS devices offer high performance, tuning by movable parts and open new perspectives at extra high frequency i.e. 30 to 300 GHz. In this thesis, cavity resonators' design and characterization are introduced, as a preliminary discussion. Their integration in the bulk of High Resistivity Silicon (HR-Si) wafers by micromachining techniques is realized at 60 and 75 GHz. Further, the tuning performance induced by internal volumes of perturbation is thoroughly investigated. Furthermore, the integration of a voltage controlled tuning system for air filled cavity resonators is realized at 60 GHz, using a MEMS based Faraday cage. Additionally, a new miniaturization concept is demonstrated using High Impedance Surfaces (HIS). A seven-pole Chebyshev bandpass filter is realized in Low Temperature Co-fired Ceramic (LTCC). Finally, ultra-low phase-noise oscillators at 60 GHz are realized using cavity resonators integrated in HR-Si and LTCC. These oscillators improve the state of the art for integrated oscillators in the frequency band from 40 to 80 GHz, demonstrating the highest factor of merit, to our best knowledge and to date, FoM = -199 dBcHz @ 1MHz offset from the carrier frequency, fosc = 59.98 GHz.

  • 15.
    Dancila, Dragos
    et al.
    EMIC, UCL, Belgium.
    Ekkels, P.
    Rottenberg, X.
    Francis, L.
    Huynen, I.
    Carchon, G.
    Tilmans, H.A.C.
    De Raedt, W.
    60 GHz tunable cavity resonator based on a perturbation by a volume inside the cavity2008Konferansepaper (Fagfellevurdert)
  • 16. Dancila, Dragos
    et al.
    Huynen, I.
    Massaoudi, S.
    Développement de structures main gauche planaires pour l'imagerie par résonance magnétique2007Konferansepaper (Fagfellevurdert)
  • 17.
    D'Angelo, Laura
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för datorteknik.
    Evaluation of code generation in agile software development of embedded systems2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Generating code from software models is considered to be a new generation leap within software development methods. The objective of this M.Sc. project is to evaluate how different approaches to modelling and code generation affect embedded systems software development and propose recommendations on how to improve software development. Two product areas at Saab Surveillance EW Systems in Järfälla, Stockholm, are used as study objects.

    A research overview is made to highlight themes regarding modelling, code generation and software development in general. Based on these, interviews are held with system engineers and software developers at each product area, where they use different modelling and code generation approaches. The two development processes are described thoroughly. Challenges and advantages related to each area’s approach are investigated.

    Software development within product area A is affected by the product complexity and the larger scale of the development, including projects running over a longer time with more teams involved. Recommendations include enabling code generation by aligning it with other investments on process improvement and limiting the approach to generating some system components. Software developers within product area B can use full code generation, enabled by the limited product complexity. The product area is affected by software standards and external requirements on the process. Recommendations include extending the modelling approach to make it easier to trace functionality from system to software level. Conclusions are that both product areas can apply modelling and code generation to more software development activities to improve their respective development processes.

  • 18.
    Edvinsson, Nils
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Energy harvesting power supply for wireless sensor networks: Investigation of piezo- and thermoelectric micro generators2013Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Computers and their constituent electronics continue to shrink. The same amount of work can be done with increasingly smaller and cheaper components that need less power to function than before. In wireless sensor networks, the energy needed by one sensor node borders the amount that is already present in its immediate surroundings. Equipping the electronics with a micro generator or energy harvester gives the possibility that it can become self-sufficient in energy.

    In this thesis two kinds of energy harvesters are investigated. One absorbs vibrations and converts them into electricity by means of piezo-electricity. The other converts heat flow through a semiconductor to electricity, utilizing a thermoelectric effect. Principles governing the performance, actual performance of off-the-shelf components and design considerations of the energy harvester have been treated. The thermoelectric micro generator has been measured to output power at 2.7 mW and 20°C with a load of 10 W. The piezoelectric micro generator has been measured to output power at 2.3 mW at 56.1 Hz, with a mechanical trim weight and a load of 565 W. In these conditions the power density of the generators lies between 2-3 W/m2.

  • 19.
    Elsts, Atis
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datalogi.
    Hassani Bijarbooneh, Farshid
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datalogi.
    Jacobsson, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Sagonas, Konstantinos
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datalogi.
    ProFuN TG: A tool for programming and managing performance-aware sensor network applications2015Inngår i: IEEE 40th Local Computer Networks Conference Workshops (LCN Workshops), IEEE Computer Society, 2015, s. 751-759Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Sensor network macroprogramming methodologiessuch as the Abstract Task Graph hold the promise of enablinghigh-level sensor network application development. However,progress in this area is hampered by the scarcity of tools, andalso because of insufficient focus on developing tool support forprogramming applications aware of performance requirements.

    We present ProFuN TG (Task Graph), a tool for designing sen-sor network applications using task graphs. ProFuN TG providesautomated task mapping, sensor node firmware macrocompila-tion, application simulation, deployment, and runtime mainte-nance capabilities. It allows users to incorporate performancerequirements in the applications, expressed through constraintson task-to-task dataflows. The tool includes middleware that usesan efficient flooding-based protocol to set up tasks in the network,and also enables runtime assurance by keeping track of theconstraint conditions.

    We show that the adaptive task reallocation enabled by ourapproach can significantly increase application reliability whiledecreasing energy consumption: in a network with unreliablelinks, we achieve above 99.89 % task-to-task PDR while keepingthe maximal radio duty cycle around 2.0 %.

  • 20.
    Elsts, Atis
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datalogi.
    Hassani Bijarbooneh, Farshid
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datalogi.
    Jacobsson, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Sagonas, Konstantinos
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datalogi.
    ProFuN TG: Programming Sensornets with Task Graphs for Increased Reliability and Energy-Efficiency2015Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Sensor network macroprogramming methodologies such as the Abstract Task Graph hold the promise of enabling high-level sensor network application development. However, progress in this area is hampered by the scarcity of tools, and also because of insufficient focus on developing tool support for programming applications aware of performance requirements.

    In this demo we present ProFuN TG (Task Graph), a tool for designing sensor network applications using task graphs. ProFuN TG provides automated task mapping, sensor nodefirmware macrocompilation, application simulation, deployment, and runtime maintenance capabilities. It allows users to incorporate performance requirements in the applications, expressed through constraints on task-to-task dataflows. The tool includes middleware that uses an efficient flooding-based protocol to set up tasks in the network, and also enables runtime assurance by keeping track of the constraint conditions.

    Through task allocation in a way that optimizes an objective function in a model of the network, and adaptive task reallocation in case of link, node, or sensor failures the tool helps to make sensornet applications both more energy-efficient and reliable.

  • 21. Elvmarker, Simon
    Visualization and simulation of idle truck energy usage: Prediction of battery discharge in a Volvo truck cab2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Volvo Group Trucks Technology has found a need for a new way to present the battery status and electricity consumption of their on-board batteries in combustion engine trucks. Many battery related issues the drivers are facing could be prevented if a tool was developed that could assist with energy planning in an intuitive way. In many cases, the climate control system will constitute the bulk of the energy supplied by the battery. In addition, the climate system energy demand is dependent on both user settings and factors beyond the driver’s control. This work describes the process of developing a grey-box Simulink model able to predict the battery charge depletion rate based on signals already sampled by many Volvo truck versions. The resulting model is able to estimate the time remaining until the battery state of charge (SOC) is getting close to the crankability (starting engine) limit or risks causing battery damage. The settings of the climate system are shown to have great impact on the battery charge depletion rate. Predicting the time until the battery will reach a critical limit, and adjusting the climate system settings accordingly, can make the difference between the battery charge lasting overnight or not. A way to implement additional influences, such as sunlight, are discussed and recommendations are given.

  • 22.
    Eriksson, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Design and implementation of a servo system by Sensor Field Oriented Control of a BLDC motor2014Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    A servo system intended to steer antennas on board ships is designed, built and tested. It uses a Brushless Direct Current (BLDC) motor with an encoder to keep track of its position, and Field Oriented Control (FOC) implemented on Toshibas microprocessor TMPM373 in order to control the current flowing to the motor. The servo system will be connected in cascade to another already existing servo system and controlled with two input signals. The first signal determines if the antenna axis should rotate clockwise or counter clockwise. The second signal is a stream of pulses, where each pulse means that the motor should move one encoder point. A printed circuit board is designed and built to complete these tasks. A proportional-integral regulator is used to control the position of the motor, using the position error as the controller input. The servo system is tested. The performance of the resulting servo system is sufficient to satisfy the required position error limit of 0.5 degrees. In order to reduce the periodic disturbances presented in the system in experiments, Iterative Learning Control (ILC) is implemented. It is shown that using ILC further decreases the position error.

  • 23.
    Feeney, Laura Marie
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Hartung, Robert
    Technische Universitaet Braunschweig, Braunschweig, Germany.
    Rohner, Christian
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Kulau, Ulf
    Technische Universitaet Braunschweig, Braunschweig, Germany.
    Wolf, Lars
    Technische Universitaet Braunschweig, Braunschweig, Germany.
    Gunningberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Towards realistic lifetime estimation in battery-powered IoT devices2017Inngår i: Proceedings of the 15th ACM Conference on Embedded Network Sensor Systems Article No. 67, Association for Computing Machinery (ACM), 2017, artikkel-id 67Konferansepaper (Fagfellevurdert)
    Abstract [en]

    We describe a testbed for studying battery discharge behavior andthe lifetime of wireless devices under controlled temperature conditions and present preliminary measurement results.

  • 24.
    Feeney, Laura Marie
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Rohner, Christian
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Gunningberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Making batteries a first class element in the design and evaluation of embedded wireless systems2017Inngår i: Proc. 14th International Conference on Embedded Wireless Systems and Networks, ACM Digital Library, 2017, s. 242-243Konferansepaper (Fagfellevurdert)
  • 25.
    Fejes, Peter
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik.
    Estimation of Steering Wheel Angle in Heavy-Duty Trucks2016Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    The project presented in this report is a master's thesis performed at Scania CV. The main purpose is to develop an algorithm that estimates the offset of the values that the steering wheel angle sensor reports in a truck or tractor, and also to investigate the possibility to estimate the steering wheel angle in real-time. The developed algorithm successfully estimates the offset to an accuracy on the order of degrees, and the uncertainty of the estimate is ultimately determined by the backlash in the steering system, which may range up to approximately 15 degrees or more depending on service standards. The investigation also shows that two general approaches to estimate the steering wheel angle in real-time can produce unbiased estimates only when the vehicle is cornering at low speeds.

  • 26.
    Giannopoulou, Georgia
    et al.
    ETH Zurich, Department of Information Technology and Electrical Engineering.
    Lampka, Kai
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Nikolay Stoimenov, Nikolay Stoimenov
    ETH Zurich, Department of Information Technology and Electrical Engineering.
    Thiele, Lothar
    ETH Zurich, Department of Information Technology and Electrical Engineering.
    Timed Model Checking with Abstractions: Towards Worst-Case Response Time Analysis in Resource-Sharing Manycore Systems2012Inngår i: Proc. International Conference on Embedded Software (EMSOFT), ACM Press, 2012, s. 63-72Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Multicore architectures are increasingly used nowadays in embedded real-time systems. Parallel execution of tasks feigns the possibility of a massive increase in performance. However, this is usually not achieved because of contention on shared resources. Concurrently executing tasks mutually block their accesses to the shared resource, causing non-deterministic delays. Timing analysis of tasks in such systems is then far from trivial. Recently, several analytic methods have been proposed for this purpose, however, they cannot model complex arbitration schemes such as FlexRay which is a common bus arbitration protocol in the automotive industry. This paper considers real-time tasks composed of superblocks, i. e., sequences of computation and re- source accessing phases. Resource accesses such as accesses to memories and caches are synchronous, i. e., they cause execution on the processing core to stall until the access is served. For such systems, the paper presents a state-based modeling and analysis approach based on Timed Automata which can model accurately arbitration schemes of any complexity. Based on it, we compute safe bounds on the worst-case response times of tasks. The scalability of the approach is increased significantly by abstracting several cores and their tasks with one arrival curve, which represents their resource accesses and computation times. This curve is then incorporated into the Timed Automata model of the system. The accuracy and scalability of the approach are evaluated with a real-world application from the automotive industry and benchmark applications.

  • 27.
    Gollbo, Simon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    Development of a platform for evaluating a GNSS positioning system2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    The project aims to develop a platform for the demonstration and evaluation of Global Navigation Satellite Systems (GNSSs). The GNSS receivers used in the project are two uBlox NEO-M8P modules, one of which is used as a reference receiver in a differential GNSS setup.

    The entire platform has been implemented and consists of a network-controlled car (NetCar) which has a GNSS receiver and a 4G module on it, a separate reference GNSS receiver, a computer hosting a control interface for controlling the NetCar and a relay server for relaying data between the control interface and the NetCar.

    The platform has been tested for evaluating the GNSS. The performance was evaluated in terms of the time to first fix (TTFF), stationary positioning accuracy and tracking accuracy which includes qualitative evaluation of accuracy, statistical evaluation of accuracy and evaluation of absolute accuracy after moving. The test results show that the platform performed well for the demonstration and evaluation of the GNSS. The evaluation results show that the TTFF for the uBlox NEO-M8P used in the project averaged 24.2 s with a worst case of 33 s. The stationary positioning accuracy was found to drift in the order of tens of centimeters when using differential GNSS in RTK float mode and in the order of centimeters in RTK fixed mode. The relative trackingaccuracy between points during either RTK mode was found to be on the order of centimeters while the absolute accuracy was found to be drifting, probably due to the reference receiver position being acquired through self-survey. The current project can be extended further by including automatic navigation, sensor fusion, pathfinding and the like.

  • 28.
    Goude, Kim
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    Development of an FPGA-based digital filter platform2017Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    This project has the aim of developing a digital filter platform based on an FPGA IC (field-programmable gate array integrated circuit). The platform can be used to design and realize digital filters of various types, such as lowpass (LP), highpass (HP), bandpass (BP) and band stop (BS) filters, in the category of either finte impulse response (FIR) or infinite impulse response (IIR). Its hardware consists of a Terasic DE1-SoC development board (having an Altera Cyclone V FPGA IC, and 10 switches plus 4 buttons on it) and a QC2004A LCD display. The LCD display together with the switches and buttons constitute the human machine interface with which the filter category (FIR or IIR) can be selected and the desired filter can be specified with cutoff frequencies, bandwidth, filter’s order, and so on. The FPGA is programmed using VHDL (VHSIC Hardware Description Language). The present project is continued from an earlier project that had already developed a platform that can create FIR filters of LP and HP with a fixed order (32th) and IIR filters of LP, HP and BS with the first and second orders. It has extended the FIR filters with selectable filter order up to 64th order and the IIR filters with up to the 6th order.

    The FIR filters are shown to fully function as expected. But the IIR filters work partly. In particular, the calculated coefficients for the IIR filters are sometimes correct, and the Altera Cyclone V FPGA IC is not powerful enough for higher filter order, e.g., 6th order.

  • 29.
    Grudén, Mathias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Wireless Sensor Network Systems in Harsh Environments and Antenna Measurement Techniques2014Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Wireless sensor network (WSN) has become a hot topic lately. By using WSN things that previously were difficult or impossible to measure has now become available. One of the main reasons using WSN for monitoring is to save money by cost optimization and/or increase safety by letting the user knowing the physical status of the monitored structure. This thesis considers four main topics, empirical testing of WSN in harsh environments, antenna designs, antenna measurements and radio environment emulation.

    The WSN has been tested in train environment for monitoring of ball bearings and inside jet engines to monitor strain of blades and temperatures. In total, two investigations have been performed aboard the train wagon and one in the jet engine. The trials have been successful and provide knowledge of the difficulties with practical WSN applications. The key issues for WSN are robust communication, energy management (including scavenging) and physical robustness.

    For the applications of WSN in harsh environments antennas has to be designed. In the thesis, two antennas has been designed, one for train environment and one for the receiver in the jet engine. In the train environment, a more isotropic radiation pattern is preferable; hence a small dual layered patch antenna is designed. The antenna is at the limit of being electrically small; hence slightly lower radiation efficiency is measured. For the WSN in the jet engine, a directive patch array is designed on an ultra-thin and flexible substrate. The thin substrate of the antenna causes rather lower radiation efficiency. But the antenna fulfils the requirements of being conformal and directive.

    In reverberation chambers are used to measure antennas, but there are difficulties to provide a realistic radio environment, for example outdoor or on-body. In this thesis, a large reverberation chamber is designed and verified. It enables measurement between 400 MHz and 3 GHz. Also, a sample selection method is designed to provide a post processing possibilities to emulate the radio environment inside the chamber. The method is to select samples from a data set that corresponds to a desired probability density function. The method presented in this thesis is extremely fast but the implementation of the method is left for future research.

    Delarbeid
    1. Field Operational Testing for Safety Improvement of Freight Trains using Wireless Monitoring by Sensor Network
    Åpne denne publikasjonen i ny fane eller vindu >>Field Operational Testing for Safety Improvement of Freight Trains using Wireless Monitoring by Sensor Network
    Vise andre…
    2013 (engelsk)Inngår i: IET Wireless Sensor Systems, ISSN 2043-6386, E-ISSN 2043-6394Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Today, the majority of wagon failures on railroad systems are because of the poor maintenance of ball bearings, which causes emergent stops and delays. The existing stationary detectors, lack in predicting failures which cause troubles in scheduling maintenance. During the fall of 2011, a trial was performed by applying a wireless sensor network (WSN) aboard a train wagon with the objective to demonstrate a proof of concept for monitoring the temperature of ball bearings aboard the train wagon. This trial investigates several key aspects when applying sensor networks such as radio wave propagation, energy scavenging and performance of the WSN aboard the wagon. Two wireless links were used in the WSN. The aboard network communicates at 2.45 GHz, and the external communication is an 868 MHz radio frequency identification radio link. Since the energy in the WSN node is limited, appropriate energy scavenging devices are also presented and evaluated in a lab environment. Effort has been made to overcome these problems. The energy consumption in the network is still a problem; the most promising energy scavenging technique is piezoelectric harvesting by vibrations, which in the experiments scavenged 2.32 mW.

    Emneord
    Wireless sensor network, train
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot elektronik
    Identifikatorer
    urn:nbn:se:uu:diva-218887 (URN)10.1049/iet-wss.2013.0048 (DOI)
    Prosjekter
    Wisenet
    Tilgjengelig fra: 2014-02-19 Laget: 2014-02-19 Sist oppdatert: 2017-12-06bibliografisk kontrollert
    2. Reliability Experiments for Wireless Sensor Networks in Train Environment
    Åpne denne publikasjonen i ny fane eller vindu >>Reliability Experiments for Wireless Sensor Networks in Train Environment
    Vise andre…
    2009 (engelsk)Inngår i: European Microwave Week (EuMWeek), Second European Wireless Technology Conference, EuWIT, 2009, s. 37-40Konferansepaper, Publicerat paper (Fagfellevurdert)
    HSV kategori
    Forskningsprogram
    Elektroteknik med inriktning mot signalbehandling; Teknisk fysik med inriktning mot mikrovågsteknik
    Identifikatorer
    urn:nbn:se:uu:diva-120593 (URN)
    Konferanse
    European Microwave Week (EuMWeek), Second European Wireless Technology Conference, EuWIT
    Prosjekter
    WISENET
    Tilgjengelig fra: 2010-03-15 Laget: 2010-03-15 Sist oppdatert: 2016-04-14bibliografisk kontrollert
    3. Design of a miniaturized patch antenna for easy deployment on metal surfaces
    Åpne denne publikasjonen i ny fane eller vindu >>Design of a miniaturized patch antenna for easy deployment on metal surfaces
    2013 (engelsk)Inngår i: Microwave and optical technology letters (Print), ISSN 0895-2477, E-ISSN 1098-2760, Vol. 55, nr 4, s. 723-727Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    A small dual-layer patch antenna designed for placement on a large conducting surface is presented. It uses the surrounding metal as a ground plane in order to reduce its size. The result is a small patch antenna with good radiation qualities in metallic surroundings. It can also be used in applications where shielding sensitive equipment from radiated fields is necessary, by using the shielding as the metal surface. It is constructed for use with the IEEE 802.15.4 standard at the 2.45 GHz ISM band. The lower layer is made in Fr-4 with standard height and width. This makes eventual serial production cheaper. The antenna has a measured total efficiency between 1.5 dB and 3.6 dB in the frequency range it is designed for. The longest side is 18.35 mm, equaling 14.9% of the wavelength.

    Emneord
    patch antennas, metallic environment, antenna measurements, compact antennas, microstrip antennas
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot elektronik
    Identifikatorer
    urn:nbn:se:uu:diva-197965 (URN)10.1002/mop.27437 (DOI)000315524800008 ()
    Tilgjengelig fra: 2013-04-08 Laget: 2013-04-08 Sist oppdatert: 2017-12-06bibliografisk kontrollert
    4. Empirical Tests of Wireless Sensor Network in Jet Engine Including Characterization of Radio Wave Propagation and Fading
    Åpne denne publikasjonen i ny fane eller vindu >>Empirical Tests of Wireless Sensor Network in Jet Engine Including Characterization of Radio Wave Propagation and Fading
    2014 (engelsk)Inngår i: IEEE Antennas and Wireless Propagation Letters, ISSN 1536-1225, E-ISSN 1548-5757, Vol. 13, s. 762-765Artikkel i tidsskrift (Fagfellevurdert) Published
    Emneord
    Wireless Sensor Network, Jet engine, Propagation
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot elektronik
    Identifikatorer
    urn:nbn:se:uu:diva-218889 (URN)10.1109/LAWP.2014.2316311 (DOI)000335565400002 ()
    Tilgjengelig fra: 2014-02-19 Laget: 2014-02-19 Sist oppdatert: 2017-12-06bibliografisk kontrollert
    5. Design and Evaluation of a Conformal Patch Antenna Array for use with Wireless Sensor Network inside Jet Engines
    Åpne denne publikasjonen i ny fane eller vindu >>Design and Evaluation of a Conformal Patch Antenna Array for use with Wireless Sensor Network inside Jet Engines
    2013 (engelsk)Konferansepaper, Publicerat paper (Fagfellevurdert)
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-218890 (URN)
    Konferanse
    European Conference on Antennas and Propagation (EuCAP), Gothenburg.
    Tilgjengelig fra: 2014-02-19 Laget: 2014-02-19 Sist oppdatert: 2014-04-29
    6. Large Ad Hoc Shielded Room with Removable Mode Stirrer for Mobile Phone Antenna Tests
    Åpne denne publikasjonen i ny fane eller vindu >>Large Ad Hoc Shielded Room with Removable Mode Stirrer for Mobile Phone Antenna Tests
    2013 (engelsk)Inngår i: IEEE transactions on electromagnetic compatibility (Print), ISSN 0018-9375, E-ISSN 1558-187X, Vol. 55, nr 1, s. 21-27Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Reverberation chambers (RC) are widely used for measuring antenna performance and parameters for MIMO systems. RCs for mobile phone antenna tests are often specially designed for this purpose. The lowest frequency of operation of an RC is decided by its size. With a trend of lower frequency bands being allocated for mobile phones, the minimum size of RCs for mobile phone antenna tests increases, and is approaching the size of a normal room. At the same time, many large shielded rooms are already in use for various electrical measurements. In this paper, a standard shielded room designed for EMC testing is used as an RC for mobile phone antenna tests. To complete the RC, a large mode stirrer is built. The fact that the room is also used for other tests requires a detachable, foldable, and lightweight stirrer design. Therefore, metal meshes are evaluated for the design of the mode stirrer. The performance of the used room is verified by standard tests for RCs, and it is verified that it is possible to measure antennas from about 400 MHz up to 4 GHz with good accuracy. The size of the room also enables measurements including humans carrying mobile phones or body area networks.

    Emneord
    Antenna measurements, electromagnetic propagation, electromagnetic shielding, microwave communication, microwave radio propagation
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot elektronik
    Identifikatorer
    urn:nbn:se:uu:diva-197409 (URN)10.1109/TEMC.2012.2204758 (DOI)000315118100003 ()
    Tilgjengelig fra: 2013-03-28 Laget: 2013-03-25 Sist oppdatert: 2017-12-06bibliografisk kontrollert
    7. Sample-Selection Method for Arbitrary Fading Emulation Using Mode-Stirred Chambers
    Åpne denne publikasjonen i ny fane eller vindu >>Sample-Selection Method for Arbitrary Fading Emulation Using Mode-Stirred Chambers
    2010 (engelsk)Inngår i: IEEE Antennas and Wireless Propagation Letters, ISSN 1536-1225, E-ISSN 1548-5757, Vol. 9, s. 409-412Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Mode-stirred chambers (MSCs) consist of one or more resonant cavities coupled in some way in order to allow the measurement of different antenna parameters such as antenna efficiency, correlation, diversity gain, or multiple-input-multiple-output (MIMO) capacity, among others. In a single-cavity MSC, also known as a reverberation chamber (RC), the environment is isotropic and the amplitude of the signal is Rayleigh distributed. Real environments, however, rarely follow an isotropic Rayleigh-fading scenario. Previous results have shown that a Rician-fading emulation can be obtained via hardware modification using an RC. The different methods lack from an accurate emulation performance and are strongly dependent upon chamber size and antenna configurations. With the innate complexity of more-than-one-cavity MSC, the coupling structure generates sample sets that are complex enough so as to contain different clusters with diverse fading characteristics. This letter presents a novel method to accurately emulate a more realistic Rician-fading distribution from a Rayleigh-fading distribution by selecting parts of the sample set that forms different statistical ensembles using a complex two-cavity multi-iris-coupled MSC. Sample selection is performed using a genetic algorithm. Results demonstrate the potential of MSCs for versatile MIMO fading emulation and over-the-air (OTA) testing. The method is patent protected by EMITE Ing., Murcia, Spain.

    Emneord
    Diversity gain, mode-stirred chamber (MSC), multiple-output (MIMO) capacity
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-136546 (URN)10.1109/LAWP.2010.2049729 (DOI)000277885900003 ()
    Tilgjengelig fra: 2010-12-14 Laget: 2010-12-13 Sist oppdatert: 2017-12-11bibliografisk kontrollert
    8. Sample Selection Algorithms for Enhanced MIMO Antenna Measurements Using Mode-Stirred Reverberation Chambers
    Åpne denne publikasjonen i ny fane eller vindu >>Sample Selection Algorithms for Enhanced MIMO Antenna Measurements Using Mode-Stirred Reverberation Chambers
    Vise andre…
    2012 (engelsk)Inngår i: IEEE Transactions on Antennas and Propagation, ISSN 0018-926X, E-ISSN 1558-2221, Vol. 60, nr 8, s. 3892-3900Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Mode-stirred reverberation chambers (MSRCs) are a useful tool for measuring several wireless-related MIMO antenna parameters. In a conventional single-cavity MSRC, the emulated fading environment is isotropic and the amplitude of the signal is Rayleigh distributed. Previous contributions have enhanced the emulation capabilities of MSRCs so as to include the ability to emulate Rician- and non-isotropic fading environments. In this contribution, arbitrary amplitude probability density functions (PDF) emulation using a MSRC is presented by selecting parts of the sample set that forms different statistical ensembles. Several algorithms are presented and compared in terms of computation time and power accuracy using simulated as well as measured data from different MSRCs to obtain Rician, on-body and amplitude PDFs of standardized models. The technique is patent-protected by EMITE.

    Emneord
    Algorithms, antenna measurements, fading channels, genetic algorithms
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot elektronik
    Identifikatorer
    urn:nbn:se:uu:diva-182546 (URN)10.1109/TAP.2012.2201103 (DOI)000308435800037 ()
    Tilgjengelig fra: 2012-10-11 Laget: 2012-10-11 Sist oppdatert: 2017-12-07bibliografisk kontrollert
  • 30.
    Grudén, Mathias
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Jobs, Magnus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Rydberg, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Empirical Tests of Wireless Sensor Network in Jet Engine Including Characterization of Radio Wave Propagation and Fading2014Inngår i: IEEE Antennas and Wireless Propagation Letters, ISSN 1536-1225, E-ISSN 1548-5757, Vol. 13, s. 762-765Artikkel i tidsskrift (Fagfellevurdert)
  • 31. Gu, Chuancai
    et al.
    Guan, Nan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Deng, Qingxu
    Yi, Wang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Improving OCBP-based scheduling for mixed-criticality sporadic task systems2013Inngår i: Proc. 19th International Conference on Embedded and Real-Time Computing Systems and Applications, IEEE Computer Society, 2013Konferansepaper (Fagfellevurdert)
  • 32. Gu, Chuancai
    et al.
    Guan, Nan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Deng, Qingxu
    Yi, Wang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Partitioned mixed-criticality scheduling on multiprocessor platforms2014Inngår i: Proc. 17th Conference on Design, Automation and Test in Europe, Piscataway, NJ: IEEE , 2014Konferansepaper (Annet vitenskapelig)
  • 33. Gyllsdorff, Niclas
    Distributed machine learning for embedded devices2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    The goal of the master thesis is to investigate the feasibility ofhaving distributed machine learning on embedded devices and toanalyse how the architecture of such a system can look like. A systemis proposed which enables machine learning running on multipleembedded devices to communicate with an end application. Theapplication communicates with the distributed machine learning via agateway, which decouples the application. The proposed system isimplemented as a proof of concept system, which utilizes distributedmachine learning to achieve gesture recognition. The Intel Curiemodule was selected as the embedded device, as it provides a hardwareaccelerated implementation of the machine learning algorithmsK-Nearest Neighbour and Radial Basis Function. This module alsoprovides accelerometer/gyroscope sensors for collecting gesture dataas well as Bluetooth Low Energy, which enables wireless communicationwith other devices. The implemented system shows that it is feasibleto implement distributed machine learning on embedded devices if themachine learning is hardware accelerated. If a hardware acceleratorwas not used the computational load on the embedded device willincrease, which will increase the overall power consumption. For alow powered and constrained devices, hardware accelerated machinelearning is likely the best approach to implement edge intelligence.

  • 34.
    Haraldsson, Jonathan
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Nordin, Julia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Construction of Robot for Visual Demonstration at Conferences and Fairs2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    A demonstration robot for conferences and fairs has been built from scratch. The demonstration robot is meant to create lasting impressions at the company booth at conferences or fairs. Thus, the robot needs traits that attract people to the booth and makes sure they remember that company. In this project, traits such as being able to move, do facial expressions and play audio have been developed. The robot has also been designed to draw as much attention as possible to the booth. This was achieved by building a robot that consists of a rolling sphere with a head that always remains on top. All movements are carried out from inside the sphere by four different motors. One motor moves the robot back and forth, two motors spin a flywheel to turn the robot and the last motor rotates the head. These motors are mounted at different places on an internal structure. The internal structure is connected to the sphere at two points, one on each side of the robot. At the top of the internal structure, magnets are placed. Thus, it can attach the head at the outside of the sphere by mounting magnets in the head. All movements of the robots are controlled by a hand controller, which has been made in this project. The head has a built-in display simulating two eyes. The display is driven by a Raspberry Pi. An internal speaker is built-in inside the head, connected to the Raspberry Pi. Each simulated eye consists of 64 squares that can be programmed to be in different colours, thus making it possible to express a wide range of facial expressions.Two PCBs were designed and manufactured to control the robot. One was placed inside the robot, and the other inside the hand controller. The PCBs can communicate over Bluetooth, which makes it possible to control the robot from the outside.All parts of the robot have been designed in a CAD program and subsequently 3D printed. 3D design in CAD was learned from a novice level, since there was no previous knowledge of this in the project group.In addition, a registration form has been developed that allows visitors to register at the booth. Making it easier for the company to connect with visitors after the conference or fair. The registration form is connected with the Raspberry Pi in the head of the robot via Wi-Fi. Thus, when new registrations occur, the robot can print the names of them while audio is played.

  • 35. Haulin, Lars
    A state-based method to model and analyze the power consumption of embedded systems2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    In this work I have evaluated a method to model, measure and analyze the power consumption of embedded systems.

    The method combines current measurement with debug trace data telling which parts of the systems that are enabled. This makes it possible to compute the individual current consumption of the parts in the system from a single measurement point.

    The method allows an embedded systems engineer to determine the power consumption of individual parts in a system to either get an overview or to compare several revisions of hardware and/or software with each other.

    The method also captures the system dynamics of the power delivery route. This makes the model consumption behave more like the actual system around state transitions.

    The case study is focused on the Arm-based microcontroller CC2650 from Texas Instruments and uses the I-scope/I-jet probe from IAR Systems to measure current consumption and collect trace data.

  • 36. Hossain, Adnan
    Diagnosis of autonomous vehicles using machine learning2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    With autonomous trucks on the road where the driver is absent requires new diagnostic methods. The driver possess several abilities which a machine does not. In this thesis, the use of machine learning as a method was investigated. A more concrete problem description was formed where the main objective was detecting anomalies in wheel configurations. More specifically, the machine learning model was used to detect incorrect wheel settings. Three different algorithms was used, SVM, LDA and logistic regression. Overall, the classifier predicts with high accuracy supporting that machine learning can be used for diagnosing autonomous vehicles.

  • 37.
    Jeong, Seung Hee
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Soft Intelligence: Liquids Matter in Compliant Microsystems2016Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Soft matter, here, liquids and polymers, have adaptability to a surrounding geometry. They intrinsically have advantageous characteristics from a mechanical perspective, such as flowing and wetting on surrounding surfaces, giving compliant, conformal and deformable behavior. From the behavior of soft matter for heterogeneous surfaces, compliant structures can be engineered as embedded liquid microstructures or patterned liquid microsystems for emerging compliant microsystems.

    Recently, skin electronics and soft robotics have been initiated as potential applications that can provide soft interfaces and interactions for a human-machine interface. To meet the design parameters, developing soft material engineering aimed at tuning material properties and smart processing techniques proper to them are to be highly encouraged. As promising candidates, Ga-based liquid alloys and silicone-based elastomers have been widely applied to proof-of-concept compliant structures.

    In this thesis, the liquid alloy was employed as a soft and stretchable electrical and thermal conductor (resistor), interconnect and filler in an elastomer structure. Printing-based liquid alloy patterning techniques have been developed with a batch-type, parallel processing scheme. As a simple solution, tape transfer masking was combined with a liquid alloy spraying technique, which provides robust processability. Silicone elastomers could be tunable for multi-functional building blocks by liquid or liquid-like soft solid inclusions. The liquid alloy and a polymer additive were introduced to the silicone elastomer by a simple mixing process. Heterogeneous material microstructures in elastomer networks successfully changed mechanical, thermal and surface properties.

    To realize a compliant microsystem, these ideas have in practice been useful in designing and fabricating soft and stretchable systems. Many different designs of the microsystems have been fabricated with the developed techniques and materials, and successfully evaluated under dynamic conditions. The compliant microsystems work as basic components to build up a whole system with soft materials and a processing technology for our emerging society.

    Delarbeid
    1. Liquid alloy printing of microfluidic stretchable electronics
    Åpne denne publikasjonen i ny fane eller vindu >>Liquid alloy printing of microfluidic stretchable electronics
    Vise andre…
    2012 (engelsk)Inngår i: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189, Vol. 22, nr 12, s. 4657-4664Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Recently, microfluidic stretchable electronics has attracted great interest from academia since conductive liquids allow for larger cross-sections when stretched and hence low resistance at longer lengths. However, as a serial process it has suffered from low throughput, and a parallel processing technology is needed for more complex systems and production at low costs. In this work, we demonstrate such a technology to implement microfluidic electronics by stencil printing of a liquid alloy onto a semi-cured polydimethylsiloxane (PDMS) substrate, assembly of rigid active components, encapsulation by pouring uncured PDMS on-top and subsequent curing. The printing showed resolution of 200 mm and linear resistance increase of the liquid conductors when elongated up to 60%. No significant change of resistance was shown for a circuit with one LED after 1000 times of cycling between a 0% and an elongation of 60% every 2 s. A radio frequency identity (RFID) tag was demonstrated using the developed technology, showing that good performance could be maintained well into the radio frequency (RF) range.

    sted, utgiver, år, opplag, sider
    Royal society of chemistry, 2012
    Emneord
    liquid alloy, printing, stretchable electronics, wireless communication
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot mikrosystemteknik; Teknisk fysik med inriktning mot elektronik
    Identifikatorer
    urn:nbn:se:uu:diva-183278 (URN)10.1039/C2LC40628D (DOI)000310865200010 ()
    Tilgjengelig fra: 2012-10-23 Laget: 2012-10-23 Sist oppdatert: 2017-12-07bibliografisk kontrollert
    2. Adhesive transfer soft lithography: low-cost and flexible rapid prototyping of microfluidic devices, Micro and Nanosystems
    Åpne denne publikasjonen i ny fane eller vindu >>Adhesive transfer soft lithography: low-cost and flexible rapid prototyping of microfluidic devices, Micro and Nanosystems
    2014 (engelsk)Inngår i: micro and nanosystems, ISSN 1876-4037, Vol. 6, s. 42-49Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    A simple and low-cost approach was proposed for prototyping PDMS based microfluidic devices by transferringadhesive film microstructures onto a flexible substrate as a mould for PDMS replicas. The microstructures were engravedon an adhesive coated film using a commercial cutting plotter and then transferred (or laminated) onto a flexiblesubstrate, allowing for engraved isolated patterns. The proposed technique was demonstrated by a hydrodynamic focusingmicrofluidic device, having splitting and re-combining sheath channels. The whole processing could be finished within 1h in a normal laboratory environment. This approach offers an easy, flexible and rapid prototyping of microfluidic andlab-on-a-chip devices to users without expertise in microfabrication. In addition, by minimizing the use of chemicals, theprocess becomes more environmentally friendly than conventional photolithography based micro-fabrication techniques.

    sted, utgiver, år, opplag, sider
    Bentham Science Publishers, 2014
    Emneord
    liquid alloy, printing, soft lithography, rapid prototyping
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot mikrosystemteknik
    Identifikatorer
    urn:nbn:se:uu:diva-239241 (URN)
    Tilgjengelig fra: 2014-12-19 Laget: 2014-12-19 Sist oppdatert: 2016-04-22
    3. Tape Transfer Printing of a Liquid Metal Alloy for Stretchable RF Electronics
    Åpne denne publikasjonen i ny fane eller vindu >>Tape Transfer Printing of a Liquid Metal Alloy for Stretchable RF Electronics
    2014 (engelsk)Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 14, nr 9, s. 16311-16321Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    In order to make conductors with large cross sections for low impedance radio frequency (RF) electronics, while still retaining high stretchability, liquid-alloy-based microfluidic stretchable electronics offers stretchable electronic systems the unique opportunity to combine various sensors on our bodies or organs with high-quality wireless communication with the external world (devices/systems), without sacrificing enhanced user comfort. This microfluidic approach, based on printed circuit board technology, allows large area processing of large cross section conductors and robust contacts, which can handle a lot of stretching between the embedded rigid active components and the surrounding system. Although it provides such benefits, further development is needed to realize its potential as a high throughput, cost-effective process technology. In this paper, tape transfer printing is proposed to supply a rapid prototyping batch process at low cost, albeit at a low resolution of 150 mu m. In particular, isolated patterns can be obtained in a simple one-step process. Finally, a stretchable radio frequency identification (RFID) tag is demonstrated. The measured results show the robustness of the hybrid integrated system when the tag is stretched at 50% for 3000 cycles.

    Emneord
    tape transfer printing, liquid metal alloy, microfluidic stretchable electronics, stretchable RF electronics, radio frequency identification (RFID) tag
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-237588 (URN)10.3390/s140916311 (DOI)000343106600041 ()
    Tilgjengelig fra: 2014-12-05 Laget: 2014-12-03 Sist oppdatert: 2017-12-05bibliografisk kontrollert
    4. Tape transfer atomization patterning of liquid alloys for microfluidic stretchable wireless power transfer
    Åpne denne publikasjonen i ny fane eller vindu >>Tape transfer atomization patterning of liquid alloys for microfluidic stretchable wireless power transfer
    2015 (engelsk)Inngår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 5, s. 8419-Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Stretchable electronics offers unsurpassed mechanical compliance on complex or soft surfaces like the human skin and organs. To fully exploit this great advantage, an autonomous system with a self-powered energy source has been sought for. Here, we present a new technology to pattern liquid alloys on soft substrates, targeting at fabrication of a hybrid-integrated power source in microfluidic stretchable electronics. By atomized spraying of a liquid alloy onto a soft surface with a tape transferred adhesive mask, a universal fabrication process is provided for high quality patterns of liquid conductors in a meter scale. With the developed multilayer fabrication technique, a microfluidic stretchable wireless power transfer device with an integrated LED was demonstrated, which could survive cycling between 0% and 25% strain over 1,000 times.

    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot mikrosystemteknik
    Identifikatorer
    urn:nbn:se:uu:diva-247504 (URN)10.1038/srep08419 (DOI)000349245600018 ()25673261 (PubMedID)
    Tilgjengelig fra: 2015-03-19 Laget: 2015-03-19 Sist oppdatert: 2017-12-04bibliografisk kontrollert
    5. Stretchable wireless power transfer with a liquid alloy coil
    Åpne denne publikasjonen i ny fane eller vindu >>Stretchable wireless power transfer with a liquid alloy coil
    2015 (engelsk)Inngår i: Micro Electro Mechanical Systems (MEMS), 2015 28th IEEE International Conference on, 2015, s. 1137-1140Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    An integrated stretchable wireless power transfer device was demonstrated by packaging rigid electronic chips onto a liquid alloy coil patterned on a half-cured polydimethylsiloxane (PDMS) surface. To obtain low enough resistance, the long liquid alloy coil with a large cross section was made with a tape transfer masking followed by spray deposition of the liquid alloy. The measured results indicated the wireless power transfer efficiency reached 10% at 140 kHz and good performance under 25% overall strain. Different sizes of liquid alloy coils and a soft magnetic composite core were tested to improve the efficiency of the system.

    Serie
    Proceedings IEEE Micro Electro Mechanical Systems, ISSN 1084-6999
    Emneord
    Liquid alloy, Stretchable electronics, Wireless power transfer, Smart system integration
    HSV kategori
    Forskningsprogram
    Materialvetenskap
    Identifikatorer
    urn:nbn:se:uu:diva-265529 (URN)10.1109/MEMSYS.2015.7051165 (DOI)000370382900296 ()978-1-4799-7955-4 (ISBN)
    Konferanse
    Micro Electro Mechanical Systems (MEMS), 2015 28th IEEE International Conference on, Estoril, January 18-22, 2015
    Tilgjengelig fra: 2015-10-31 Laget: 2015-10-31 Sist oppdatert: 2016-04-21bibliografisk kontrollert
    6. Mechanically Stretchable and Electrically Insulating Thermal Elastomer Composite by Liquid Alloy Droplet Embedment
    Åpne denne publikasjonen i ny fane eller vindu >>Mechanically Stretchable and Electrically Insulating Thermal Elastomer Composite by Liquid Alloy Droplet Embedment
    Vise andre…
    2015 (engelsk)Inngår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 5, artikkel-id 18257Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Stretchable electronics and soft robotics have shown unsurpassed features, inheriting remarkable functions from stretchable and soft materials. Electrically conductive and mechanically stretchable materials based on composites have been widely studied for stretchable electronics as electrical conductors using various combinations of materials. However, thermally tunable and stretchable materials, which have high potential in soft and stretchable thermal devices as interface or packaging materials, have not been sufficiently studied. Here, a mechanically stretchable and electrically insulating thermal elastomer composite is demonstrated, which can be easily processed for device fabrication. A liquid alloy is embedded as liquid droplet fillers in an elastomer matrix to achieve softness and stretchability. This new elastomer composite is expected useful to enhance thermal response or efficiency of soft and stretchable thermal devices or systems. The thermal elastomer composites demonstrate advantages such as thermal interface and packaging layers with thermal shrink films in transient and steady-state cases and a stretchable temperature sensor.

    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-272055 (URN)10.1038/srep18257 (DOI)000366451800001 ()26671673 (PubMedID)
    Forskningsfinansiär
    Swedish Research Council, 621-2010-5443 621-2014-5596Swedish Foundation for Strategic Research , EM11-0002 SE13-0061
    Tilgjengelig fra: 2016-01-12 Laget: 2016-01-11 Sist oppdatert: 2017-11-30bibliografisk kontrollert
    7. PDMS-Based Elastomer Tuned Soft, Stretchable, and Sticky for epidermal electronics
    Åpne denne publikasjonen i ny fane eller vindu >>PDMS-Based Elastomer Tuned Soft, Stretchable, and Sticky for epidermal electronics
    Vise andre…
    2016 (engelsk)Inngår i: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 28, nr 28, s. 5830-5836Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Targeting good user experiences, softness and stretchability are essential features for epidermal devices in body signal monitoring and body area stimulation. A highly soft, stretchable and sticky polydimethylsiloxane based elastomer (S3-PDMS) is achieved by a simple process with a widely used siloxane precursors, the properties of which are tuned by adding small fractions of an amine-based polymer, ethoxylated polyethylenimine (EPEI). This allows formation of a thick unobstrusive patch and may ease implementation of epidermal electronics in wearable healthcare applications. 

    Emneord
    Adhesion, Compliance, Elongation at break, Epidermal electronics, PDMS-based elastomer tuning
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot materialvetenskap
    Identifikatorer
    urn:nbn:se:uu:diva-281212 (URN)10.1002/adma.201505372 (DOI)000382400900004 ()
    Forskningsfinansiär
    Swedish Research Council, 2010-5443
    Tilgjengelig fra: 2016-03-21 Laget: 2016-03-21 Sist oppdatert: 2017-11-30bibliografisk kontrollert
    8. Stretchable thermoelectric generators metallized with liquid alloy
    Åpne denne publikasjonen i ny fane eller vindu >>Stretchable thermoelectric generators metallized with liquid alloy
    Vise andre…
    2017 (engelsk)Inngår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 9, nr 18, s. 15791-15797Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Conventional thermoelectric generators (TEGs) are normally hard, rigid, and flat. However, most objects have curvy surfaces, which require soft and even stretchable TEGs for maximizing efficiency of thermal energy harvesting. Here, soft and stretchable TEGs using conventional rigid Bi2Te3 pellets metallized with a liquid alloy is reported. The fabrication is implemented by means of a tailored layer-by-layer fabrication process. The STEGs exhibit an output power density of 40.6 mu W/cm(2) at room temperature. The STEGs are operational after being mechanically stretched-and-released more than 1000 times, thanks to the compliant contact between the liquid alloy interconnects and the rigid pellets. The demonstrated interconnect scheme will provide a new route to the development of soft and stretchable energy-harvesting avenues for a variety of emerging electronic applications.

    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-281213 (URN)10.1021/acsami.7b04752 (DOI)000401307100064 ()28453282 (PubMedID)
    Forskningsfinansiär
    Swedish Foundation for Strategic Research , EM11-0002, SE13-0061Swedish Research Council, 621-2014-5596
    Tilgjengelig fra: 2016-03-21 Laget: 2016-03-21 Sist oppdatert: 2017-07-04bibliografisk kontrollert
  • 38.
    Jobs, Magnus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Design and Performance of Diversity based Wireless Interfaces for Sensor Network Nodes2013Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The main focus of the work presented in this licentiate thesis concerns antenna design, adaptive antenna control and investigation on how the performance of small wireless nodes can be increased by inclusion of multiple antennas. In order to provide an end-user suitable solution for wireless nodes the devices require both small form factor and good performance in order to be competitive on the marked and thus the main part of this thesis focuses on techniques developed to achieve these goals. Two prototype systems have been developed where one has been used by National Defence Research Agency (FOI) to successfully monitor a test-subject moving in an outdoor terrain. The other prototype system shows the overall performance gain achievable in a wireless sensor node when multiple antennas and antenna beam steering is used. As an example of how to include multiple antennas in a wireless node the concept of using dual conformal patch antennas for wireless nodes is presented. The proposed antenna showed an excess of 10 dB gain when using a single driven antenna element as would be the case in a system utilizing antenna selection combining. When used as a 2-element phased array, up to 19 dB gain was obtained in a multiscattering environment. Using the second order resonance the proposed antenna structure achieves low mutual coupling and a reflection coefficient lower than -15 dB. The presented antenna design shows how a dual antenna wireless node can be designed using discrete phase control with passive matching which provides a good adaptive antenna solution usable for wireless sensor networks. The inclusion of discrete phase sweep diversity in a wireless node has been evaluated and shown to provide a significant diversity gain. The diversity gain of a discrete phase sweep diversity based system was measured in both a reverberation chamber and a real life office environment. The former environment showed between 5.5 to 10.3 dB diversity gain depending on the detector architecture and the latter showed a diversity gain ranging from 1 to 5.4 dB. Also the performance of nodes designed to be placed in a high temperature and multiscattering environment (the fan stage of a jet engine) has been evaluated. The work was carried out in order to verify that a wireless sensor network is able to operate in such a multiscattering environment. It was shown that the wireless nodes are able to operate in an emulated turbine environment based on real-life measured turbine fading data. The tested sensor network was able to transmit 32 byte packages using cyclic redundancy check at 2 Mbps at an engine speed of 13.000 rpm.

    Delarbeid
    1. Conformal dual patch antenna for diversity based sensor nodes
    Åpne denne publikasjonen i ny fane eller vindu >>Conformal dual patch antenna for diversity based sensor nodes
    2012 (engelsk)Inngår i: Electronics Letters, ISSN 0013-5194, E-ISSN 1350-911X, Vol. 48, nr 6, s. 306-307Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    A conformal antenna structure based on dual triangular patches is presented. The dual antennas are designed to be used in diversity based sensor node applications and are integrated in the enclosure of the node. The internal shielded enclosure houses the required electronics and power supply. Simulations and measurements show acceptable diversity performance and efficiency in the second resonance mode.

    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot mikrovågsteknik; Teknisk fysik med inriktning mot elektronik
    Identifikatorer
    urn:nbn:se:uu:diva-172827 (URN)10.1049/el.2012.0088 (DOI)000301439000005 ()
    Prosjekter
    WISENET
    Forskningsfinansiär
    Vinnova, WISENET
    Tilgjengelig fra: 2012-04-17 Laget: 2012-04-16 Sist oppdatert: 2017-12-07bibliografisk kontrollert
    2. Diversity Techniques for Robustness and Power Awareness in Wireless Sensor Systems for Railroad Transport Applications
    Åpne denne publikasjonen i ny fane eller vindu >>Diversity Techniques for Robustness and Power Awareness in Wireless Sensor Systems for Railroad Transport Applications
    2011 (engelsk)Inngår i: Sustainable Wireless Sensor Networks / [ed] Winston Seah and Yen Kheng Tan, InTech Open Publishers , 2011, 1, s. 75-95Kapittel i bok, del av antologi (Fagfellevurdert)
    sted, utgiver, år, opplag, sider
    InTech Open Publishers, 2011 Opplag: 1
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-159204 (URN)978-953-307-297-5 (ISBN)
    Prosjekter
    wisenet
    Tilgjengelig fra: 2011-09-25 Laget: 2011-09-25 Sist oppdatert: 2016-04-20bibliografisk kontrollert
    3. Antenna diversity with opportunistic combining for ASk systems with single channel receivers
    Åpne denne publikasjonen i ny fane eller vindu >>Antenna diversity with opportunistic combining for ASk systems with single channel receivers
    2010 (engelsk)Inngår i: Proceedings of the Fourth European Conference on Antennas and Propagation (EuCAP), 2010, s. 1-5Konferansepaper, Publicerat paper (Fagfellevurdert)
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-138838 (URN)
    Konferanse
    Fourth European Conference on Antennas and Propagation (EuCAP)
    Prosjekter
    WISENET
    Tilgjengelig fra: 2010-12-20 Laget: 2010-12-20 Sist oppdatert: 2016-04-18bibliografisk kontrollert
    4. Performance Evaluation of a Conformal Dual Patch Antenna in an Indoor Environment
    Åpne denne publikasjonen i ny fane eller vindu >>Performance Evaluation of a Conformal Dual Patch Antenna in an Indoor Environment
    2013 (engelsk)Inngår i: 7th European Conference on Antennas and Propagation (EuCAP), 2013, s. 439-442Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    The performance of a conformal dual patch antenna design for wireless sensor networks were measured and evaluated in a real world multi-scattering environment. Both simulated and measured radiation patterns when using the antenna as a two element phased array were measured and corresponded well. The environment was measured and show strong fading characteristics. The measured data shows that the proposed structure gives a distinct advantage to the nodes communication compared to single element antennas while keeping the form factor suitable for integration of embedded hardware.

    Serie
    Proceedings of the European Conference on Antennas and Propagation, ISSN 2164-3342
    Emneord
    Antenna, Array, Reconfigurable, Conformal, Sensor, WSN, Indoor, Steerable, Performance
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot mikrovågsteknik
    Identifikatorer
    urn:nbn:se:uu:diva-198643 (URN)000327126000100 ()978-88-907018-3-2 (ISBN)
    Konferanse
    7th European Conference on Antennas and Propagation (EuCAP), APR 08-12, 2013, Gothenburg, SWEDEN
    Prosjekter
    WISENET
    Tilgjengelig fra: 2013-04-22 Laget: 2013-04-22 Sist oppdatert: 2015-03-09bibliografisk kontrollert
    5. Wireless sensor networks for aircraft engines
    Åpne denne publikasjonen i ny fane eller vindu >>Wireless sensor networks for aircraft engines
    Vise andre…
    2011 (engelsk)Konferansepaper, Publicerat paper (Fagfellevurdert)
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot elektronik
    Identifikatorer
    urn:nbn:se:uu:diva-138847 (URN)
    Konferanse
    Smart Systems Integration Conference, Dresden, Germany, 22-23.03.2011
    Prosjekter
    wisenet
    Tilgjengelig fra: 2010-12-20 Laget: 2010-12-20 Sist oppdatert: 2016-04-20bibliografisk kontrollert
    6. Wireless body area network (WBAN) monitoring application system (MASS) for personal monitoring
    Åpne denne publikasjonen i ny fane eller vindu >>Wireless body area network (WBAN) monitoring application system (MASS) for personal monitoring
    Vise andre…
    2009 (engelsk)Inngår i: 6th edition of the International Workshop on Wearable Micro and Nano Technologies for Personalised Health (pHealth 2009), Oslo, Norge, 2009Konferansepaper, Publicerat paper (Fagfellevurdert)
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot mikrovågsteknik
    Identifikatorer
    urn:nbn:se:uu:diva-121065 (URN)
    Konferanse
    6th edition of the International Workshop on Wearable Micro and Nano Technologies for Personalised Health (pHealth 2009), Oslo, Norge
    Prosjekter
    WISENET
    Tilgjengelig fra: 2010-03-18 Laget: 2010-03-18 Sist oppdatert: 2016-04-14bibliografisk kontrollert
  • 39.
    Jobs, Magnus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Wireless Interface Technologies for Sensor Networks2015Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The main focus of the work presented in this thesis concerns the development and improvement of Wireless Sensor Networks (WSNs) as well as Wireless Body Area Networks (WBANs). WSN consist of interlinked, wireless devices (nodes) capable of relaying data wirelessly between the nodes. The applications of WSNs are very broad and cover both wireless fitness monitoring systems such as pulse watches or wireless temperature monitoring of buildings, among others.

    The topics investigated in the work presented within this thesis covers antenna design, wireless propagation environment evaluation and modeling, adaptive antenna control and wireless nodes system design and evaluation. In order to provide an end-user suitable solution for wireless nodes the devices require both small form factor and good performance in order to be competitive on the marked and thus the main part of this thesis focuses on techniques developed and data collected to help achieve these goals. 

    Several different prototype systems have been developed which have been used to measure data by the Swedish Defence Research Agency (FOI), GKN Aerospace Sweden AB, the Swedish Transport Administration. The system developed with GKN Aerospace was used to do real-time test measurements inside a running RM12 jet engine and required a substantial amount of measurements, environmental modeling and system validation in order to properly design a wireless system suitable for the harsh and fast fading environment inside a jet engine. For FOI improvements were made on a wearable wireless body area network initially developed during the authors master thesis work. Refinements included work on new generation wireless nodes, antenna packaging and node-supported diversity techniques.

    Work and papers regarding the design of different types of antennas suitable for wireless nodes are presented. The primary constraints on the presented antennas are the limited electrical size. The types of antennas developed include electrically small helix antennas manufactured both on stretchable substrates consisting of a PDMS substrate with Galinstan as the liquid metal conductors, screen printed silver ink for helix antennas and conformal dual patch antennas for wireless sensor nodes. Other standard type antennas are included on the wireless sensors as well.

    Delarbeid
    1. A Tunable Spherical Cap Microfluidic Electrically Small Antenna
    Åpne denne publikasjonen i ny fane eller vindu >>A Tunable Spherical Cap Microfluidic Electrically Small Antenna
    2013 (engelsk)Inngår i: Small, ISSN 1613-6810, E-ISSN 1613-6829, Vol. 9, nr 19, s. 3230-3234Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    We present a novel microfluidic three-dimensional elec- trically small antenna (ESA). It is easy to construct simply by pneumatically inflating a planar stretchable liquid alloy microfluidic antenna into a spherical cap. Its center frequency is tuned when it is inflated; demonstrating combined high efficiency and a wide tunable frequency range around its hemispherical shape.

    sted, utgiver, år, opplag, sider
    Weinheim: John Wiley & Sons, 2013
    Emneord
    microfluidic electronics
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot materialvetenskap; Teknisk fysik med inriktning mot mikrosystemteknik; Teknisk fysik med inriktning mot elektronik
    Identifikatorer
    urn:nbn:se:uu:diva-198541 (URN)10.1002/smll.201300070 (DOI)000327899900007 ()
    Prosjekter
    VR Forass to Wu, and Wisenet
    Tilgjengelig fra: 2013-04-19 Laget: 2013-04-19 Sist oppdatert: 2017-12-06bibliografisk kontrollert
    2. Antenna diversity with opportunistic combining for ASk systems with single channel receivers
    Åpne denne publikasjonen i ny fane eller vindu >>Antenna diversity with opportunistic combining for ASk systems with single channel receivers
    2010 (engelsk)Inngår i: Proceedings of the Fourth European Conference on Antennas and Propagation (EuCAP), 2010, s. 1-5Konferansepaper, Publicerat paper (Fagfellevurdert)
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-138838 (URN)
    Konferanse
    Fourth European Conference on Antennas and Propagation (EuCAP)
    Prosjekter
    WISENET
    Tilgjengelig fra: 2010-12-20 Laget: 2010-12-20 Sist oppdatert: 2016-04-18bibliografisk kontrollert
    3. Empirical Tests of Wireless Sensor Network in Jet Engine Including Characterization of Radio Wave Propagation and Fading
    Åpne denne publikasjonen i ny fane eller vindu >>Empirical Tests of Wireless Sensor Network in Jet Engine Including Characterization of Radio Wave Propagation and Fading
    2014 (engelsk)Inngår i: IEEE Antennas and Wireless Propagation Letters, ISSN 1536-1225, E-ISSN 1548-5757, Vol. 13, s. 762-765Artikkel i tidsskrift (Fagfellevurdert) Published
    Emneord
    Wireless Sensor Network, Jet engine, Propagation
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot elektronik
    Identifikatorer
    urn:nbn:se:uu:diva-218889 (URN)10.1109/LAWP.2014.2316311 (DOI)000335565400002 ()
    Tilgjengelig fra: 2014-02-19 Laget: 2014-02-19 Sist oppdatert: 2017-12-06bibliografisk kontrollert
    4. Modelling of EM Propagation in Simplified Jet Turbine Structure using Helical Rays
    Åpne denne publikasjonen i ny fane eller vindu >>Modelling of EM Propagation in Simplified Jet Turbine Structure using Helical Rays
    2015 (engelsk)Inngår i: Electronics Letters, ISSN 0013-5194, E-ISSN 1350-911X, Vol. 51, nr 11, s. 809-811Artikkel i tidsskrift, Letter (Fagfellevurdert) Published
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-239397 (URN)10.1049/el.2014.4465 (DOI)000354773500005 ()
    Tilgjengelig fra: 2014-12-22 Laget: 2014-12-22 Sist oppdatert: 2017-12-05bibliografisk kontrollert
    5. Hemispherical coil electrically small antenna made by stretchable conductors printing and plastic thermoforming
    Åpne denne publikasjonen i ny fane eller vindu >>Hemispherical coil electrically small antenna made by stretchable conductors printing and plastic thermoforming
    2015 (engelsk)Inngår i: Journal of Micromechanics and Microengineering, ISSN 0960-1317, E-ISSN 1361-6439, Vol. 25, nr 2, artikkel-id 027004Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    A production scalable technique is presented to make hemispherical coil antennas by using a stretchable printed silver paste conductor and plastic thermoforming. To ease the fabrication process an unbalanced feed-structure was designed for solderless mounting on conductive materials. The manufactured antenna had a resonance frequency of 2.467 GHz with a reflection coefficient of -33.8 dB. The measured and simulated radiation patterns corresponded to that of monopole structure and the measured efficiency was 40%.

    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot mikrosystemteknik; Teknisk fysik med inriktning mot elektronik
    Identifikatorer
    urn:nbn:se:uu:diva-238904 (URN)10.1088/0960-1317/25/2/027004 (DOI)000349106800024 ()
    Tilgjengelig fra: 2014-12-17 Laget: 2014-12-17 Sist oppdatert: 2017-12-05bibliografisk kontrollert
    6. Measurements and Simulations of Wave Propagation for Wireless Sensor Networks in Jet Engine Turbines
    Åpne denne publikasjonen i ny fane eller vindu >>Measurements and Simulations of Wave Propagation for Wireless Sensor Networks in Jet Engine Turbines
    2011 (engelsk)Inngår i: IEEE Antennas and Wireless Propagation Letters, ISSN 1536-1225, E-ISSN 1548-5757, Vol. 10, s. 1139-1142Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    In this letter, measurements and simulations of wave propagation inside a jet engine fan have been performed. The investigation was done using both EM simulations of different cases of propagation inside the engine and by measuring the corresponding cases inside a half-scale model of a jet engine fan. The average path loss was calculated, and the shapes of the fading distributions were extracted. The time between two consecutive fading dips was measured in the empirical part. Measurements were performed with engine speeds of both 30 and 60 rpm and were shown to be linearly scalable from 60 rpm to full speed of 10 000 rpm. The results showed an average path loss of about 55 dB. When scaling the measurements from 60 rpm to full-speed rotation of about 10 000 rpm, the fading was so severe that the time slot between consecutive fading dips was limited to 290 mu s.

    Emneord
    Communication channels, electromagnetic propagation, propagation losses, radio communication, radiowave propagation
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot elektronik
    Identifikatorer
    urn:nbn:se:uu:diva-161778 (URN)10.1109/LAWP.2011.2171309 (DOI)000296260200004 ()
    Tilgjengelig fra: 2011-11-21 Laget: 2011-11-17 Sist oppdatert: 2017-12-08bibliografisk kontrollert
    7. Conformal dual patch antenna for diversity based sensor nodes
    Åpne denne publikasjonen i ny fane eller vindu >>Conformal dual patch antenna for diversity based sensor nodes
    2012 (engelsk)Inngår i: Electronics Letters, ISSN 0013-5194, E-ISSN 1350-911X, Vol. 48, nr 6, s. 306-307Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    A conformal antenna structure based on dual triangular patches is presented. The dual antennas are designed to be used in diversity based sensor node applications and are integrated in the enclosure of the node. The internal shielded enclosure houses the required electronics and power supply. Simulations and measurements show acceptable diversity performance and efficiency in the second resonance mode.

    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot mikrovågsteknik; Teknisk fysik med inriktning mot elektronik
    Identifikatorer
    urn:nbn:se:uu:diva-172827 (URN)10.1049/el.2012.0088 (DOI)000301439000005 ()
    Prosjekter
    WISENET
    Forskningsfinansiär
    Vinnova, WISENET
    Tilgjengelig fra: 2012-04-17 Laget: 2012-04-16 Sist oppdatert: 2017-12-07bibliografisk kontrollert
    8. Performance Evaluation of a Conformal Dual Patch Antenna in an Indoor Environment
    Åpne denne publikasjonen i ny fane eller vindu >>Performance Evaluation of a Conformal Dual Patch Antenna in an Indoor Environment
    2013 (engelsk)Inngår i: 7th European Conference on Antennas and Propagation (EuCAP), 2013, s. 439-442Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    The performance of a conformal dual patch antenna design for wireless sensor networks were measured and evaluated in a real world multi-scattering environment. Both simulated and measured radiation patterns when using the antenna as a two element phased array were measured and corresponded well. The environment was measured and show strong fading characteristics. The measured data shows that the proposed structure gives a distinct advantage to the nodes communication compared to single element antennas while keeping the form factor suitable for integration of embedded hardware.

    Serie
    Proceedings of the European Conference on Antennas and Propagation, ISSN 2164-3342
    Emneord
    Antenna, Array, Reconfigurable, Conformal, Sensor, WSN, Indoor, Steerable, Performance
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot mikrovågsteknik
    Identifikatorer
    urn:nbn:se:uu:diva-198643 (URN)000327126000100 ()978-88-907018-3-2 (ISBN)
    Konferanse
    7th European Conference on Antennas and Propagation (EuCAP), APR 08-12, 2013, Gothenburg, SWEDEN
    Prosjekter
    WISENET
    Tilgjengelig fra: 2013-04-22 Laget: 2013-04-22 Sist oppdatert: 2015-03-09bibliografisk kontrollert
    9. Diversity Techniques for Robustness and Power Awareness in Wireless Sensor Systems for Railroad Transport Applications
    Åpne denne publikasjonen i ny fane eller vindu >>Diversity Techniques for Robustness and Power Awareness in Wireless Sensor Systems for Railroad Transport Applications
    2011 (engelsk)Inngår i: Sustainable Wireless Sensor Networks / [ed] Winston Seah and Yen Kheng Tan, InTech Open Publishers , 2011, 1, s. 75-95Kapittel i bok, del av antologi (Fagfellevurdert)
    sted, utgiver, år, opplag, sider
    InTech Open Publishers, 2011 Opplag: 1
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-159204 (URN)978-953-307-297-5 (ISBN)
    Prosjekter
    wisenet
    Tilgjengelig fra: 2011-09-25 Laget: 2011-09-25 Sist oppdatert: 2016-04-20bibliografisk kontrollert
    10. Wireless body area network (WBAN) monitoring application system (MASS) for personal monitoring
    Åpne denne publikasjonen i ny fane eller vindu >>Wireless body area network (WBAN) monitoring application system (MASS) for personal monitoring
    Vise andre…
    2009 (engelsk)Inngår i: 6th edition of the International Workshop on Wearable Micro and Nano Technologies for Personalised Health (pHealth 2009), Oslo, Norge, 2009Konferansepaper, Publicerat paper (Fagfellevurdert)
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot mikrovågsteknik
    Identifikatorer
    urn:nbn:se:uu:diva-121065 (URN)
    Konferanse
    6th edition of the International Workshop on Wearable Micro and Nano Technologies for Personalised Health (pHealth 2009), Oslo, Norge
    Prosjekter
    WISENET
    Tilgjengelig fra: 2010-03-18 Laget: 2010-03-18 Sist oppdatert: 2016-04-14bibliografisk kontrollert
  • 40.
    Johansson, Oscar
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Wassénius, Lucas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Estimation of Orientation in a Dual-Tag Ultra Wideband Indoor Positioning System2019Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    In this report the feasibility of using a dual-tag setup in an indoor positioning system was investigated. The reason for the dual-tag setup was to be able to estimate both position and orientation. The system was designed using UWB-technology, with an time of flight trilateration algorithm to calculate the position. The orientation was then estimated from the relative position between the two tags. The system was tested both with stationary tags, but also with the tags moving along two paths. These tests were conducted for different separation distance between the tags, namely 20 cm, 30 cm and 40 cm. The result was that the mean position error for stationary tags was less than 8 cm for all separations and the mean orientation error was less than 3$^\circ$ for all separations. For the moving tag tests a decrease of the error in orientation of about 30 \% could be observed for a separation of 30 and 40 cm compared to 20 cm. However this difference is small in absolute values so more tests are needed to draw any conclusion about whether 30 and 40 cm tag separation performs better than 20 cm tag separation. The performance of the system could also be increased further by optimizing the anchor placement as well as the calibration of the antenna delays of the UWB-modules. 

  • 41.
    Johnson, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    Extended Bluetooth Profiles on CCpilot displays2017Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Bluetooth is used in modern cars to connect smartphones to stream music, to access internet and for phone services such as phone book contacts and making calls. Similar features are now requested by customers of maximatecc's products, e.g. display computers, for offroad vehicles. This thesis is aimed to investigate what is needed to support these features in maximatecc's Linux based displays and how the features can be used in a Qt application.

    For instance, the connectivity features in personal cars most commonly utilizes the Bluetooth profiles:

    Advanced Audio Distribution Profile (A2DP)

    Audio/Video Remote Control Profile (AVRCP)

    Personal Area Network (PAN) Profile

    Hands Free Profile (HFP)

    Phone Book Access Profile (PBAP)

    Message Access Profile (MAP).

    In Linux operating system the Bluetooth stack Bluez is used in the lower level implementation. Open source software components recommended to implement the above profiles includes:

    Obexd (for MAP and PBAP)

    PulseAudio (for A2DP and HFP)

    oFono (for HFP)

    Connman (for PAN)

    all of which help to implement the top level profiles of the Bluetooth stack needed, easily controlled by a Qt application through DBus.

    Most of the external software components were not possible to add to the Linux image on the CCpilot VA display during the period of the thesis. Instead some features of the profiles have been tested, through a Qt demo and python test scripts, on a Virtual Machine in an environment similar to the CCpilot VA. All profiles tested had some functionality verified except for AVRCP, which is not supported until later versions of Bluez, not available for the Linux kernel on the CCpilot VA. However, the audio in the HFP only occasionally worked. On the CCpilot VA only PBAP was tested successfully.

  • 42.
    Joldes, Mioara
    et al.
    LAAS CNRS, 7 Ave Colonel Roche, F-31077 Toulouse, France..
    Muller, Jean-Michel
    ENS Lyon, LIP Lab, 46 Allee Italie, F-69364 Lyon 07, France..
    Popescu, Valentina
    ENS Lyon, LIP Lab, 46 Allee Italie, F-69364 Lyon 07, France..
    Tucker, Warwick
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Matematiska institutionen, Tillämpad matematik och statistik.
    CAMPARY: Cuda Multiple Precision Arithmetic Library and Applications2016Inngår i: Mathematical Software, ICMS 2016 / [ed] Greuel, GM; Koch, T; Paule, P; Sommese, A, 2016, s. 232-240Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Many scientific computing applications demand massive numerical computations on parallel architectures such as Graphics Processing Units (GPUs). Usually, either floating-point single or double precision arithmetic is used. Higher precision is generally not available in hardware, and software extended precision libraries are much slower and rarely supported on GPUs. We develop CAMPARY: a multipleprecision arithmetic library, using the CUDA programming language for the NVidia GPU platform. In our approach, the precision is extended by representing real numbers as the unevaluated sum of several standard machine precision floating-point numbers. We make use of error-free transforms algorithms, which are based only on native precision operations, but keep track of all rounding errors that occur when performing a sequence of additions and multiplications. This offers the simplicity of using hardware highly optimized floating-point operations, while also allowing for rigorously proven rounding error bounds. This also allows for easy implementation of an interval arithmetic. Currently, all basic multiple-precision arithmetic operations are supported. Our target applications are in chaotic dynamical systems or automatic control.

  • 43.
    Jonsson, Kristoffer
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Lundberg, David
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Digital Interface for Intelligent Sensors2013Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Digital Interface for Intelligent Sensors was a project whose goal was to create a digital network interface that enabled easy distribution of data from different types of digital sensors to a central computer. The purpose was to replace the already existing analogue data collection system, in order to benefit from the advantages of digital communication. This demanded a software protocol that satisfyingly would be implementable on a microcontroller. Along with software implementation the specific objective was to design, construct and build an intelligent hardware sensor device. This device was supposed to measure temperature, humidity, wind direction and wind speed by collecting information from adequate digital transducers.

    The project involved researches about bus-protocols as well as practically design and build circuits. A lot of software programming was made during the project, to get the device to work as expected. During research the Modbus-protocol was found to be the best option for our specific software needs. As for the hardware part, the core of the sensor device was based on an ATmega328 microcontroller. The ATmega328 proved to be a suitable hardware platform for implementing both the Modbus-protocol and the necessary code required to extract information from the transducers. By linking a computer to the system, working as a master, weather data from the device were able to be logged.

    The device was successfully installed on the roof at Ångströmslaboratoriet, house 2. The complete system enables other digital, Modbus implemented, devices to connect in order to communicate with the central computer. Having many devices can lead to rather complex systems. The system created in this project keeps track on all the installed devices using addresses, making a complex system easy to manage.

    The project also involved a brief collaboration with another group constructing a different digital measuring device. This device was able to connect to the system using the same Modbus-protocol and thereby communicating with the central computer.

  • 44.
    Kiffer, Oliver
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Troubleshooting Scania Vehicles, Marine and Industrial Engines with External Sensors2015Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    One factor controlling a vehicles total cost is the time it is available to generate revenue for the customer, time spent in a repair shop decreases that amount. Scania vehicles are equipped with onboard diagnostics which produces fault-codes if the internal signals deviate from their intended values. These fault codes are not always enough to isolate the problem which means that the workshop staff are required to use external measuring systems to diagnose the vehicle. Combining data from internal sensors with an external measuring system can be problematic and the results inconclusive. This thesis presents a solution where signals from external and internal sensors can be logged and analyzed together. A study on various hardware typologies are presented, key problems are identified and discussed. A prototype was created based on the research done during this project. This prototype was successfully used to troubleshoot and find a problem on a test rig where an error had been purposely introduced, reducing the whole troubleshooting process to a fraction of the time it normally takes. The hardware and software necessary to create this prototype is described in this thesis.

  • 45. Kumar, Pratyush
    et al.
    Goswami, Dip
    Chakraborty, Samarjit
    Annaswamy, Anuradha
    Lampka, Kai
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Thiele, Lothar
    A Hybrid Approach to Cyber-Physical Systems Verification2012Inngår i: Proc. 49th Design Automation Conference, Association for Computing Machinery (ACM), 2012, s. 688-696Konferansepaper (Fagfellevurdert)
  • 46.
    Lampka, Kai
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Giannopolou, Georgia
    ETH Zürich.
    Pellizzoni, Rodolfo
    University of Waterloo.
    Wu, Zheng
    University of Waterloo.
    Stoimenov, Nikolay
    ETH Zürich.
    A formal approach to the WCRT analysis of multicore systems with memory contention under phase-structured task sets2014Inngår i: Real-time systems, ISSN 0922-6443, E-ISSN 1573-1383, Vol. 50, nr 5-6, s. 736-773Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Multicore technology has the potential for drastically increasing productivity of embedded real-time computing. However, joint use of hardware, e.g., caches, memory banks and on-chip buses makes the integration of multiple real-time applications into a single system difficult: resource accesses are exclusive and need to be sequenced. Moreover, resource access schemes of modern off-the-shelf multicore chips are commonly optimized for the average-case, rather than being timing predictable. Real-time analysis for such architectures is complex, as execution times depend on the deployed hardware, as well as on the software executing on other cores. This will ask for significant abstractions in the timing analysis, where the resulting pessimism will lead to over-provisioned system designs and a lowered productivity as the number of applications to be put together into a single architecture needs to be decreased. In response to this, (a) we present a formal approach for bounding the worst-case response time of concurrently executing real-time tasks under resource contention and almost arbitrarily complex resource arbitration policies, with a focus on main memory as shared resource, (b) we present a simulation framework which allows for detailed modeling and empirical evaluation of modern multicore platforms and applications running on top of them, and (c) we present experiments to demonstrate the advantages and disadvantages of the presented methodologies and compare their accuracy. For limiting non-determinism inherent to the occurrence of cache misses, we particularly take advantage from the predictable execution model as discussed in recent works.

  • 47.
    Lampka, Kai
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Perathoner, Simon
    ETH Zürich, Computer Engineering and Communication Networks Laboratory.
    Thiele, Lothar
    ETH Zürich, Computer Engineering and Communication Networks Laboratory.
    Component-based system design: analytic real-time interfaces for state-based component implementations2013Inngår i: International Journal on Software Tools for Technology Transfer (STTT), ISSN 1385-4879, E-ISSN 1571-8115, Vol. 15, nr 3, s. 155-170Artikkel i tidsskrift (Fagfellevurdert)
  • 48.
    Larsson, Mats
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    Development of a Digital Universal Filter Bank2016Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    This is a master's thesis project, which is a part of the Master Programme in Electrical Engineering at Uppsala university.

    When developing a product or performing measurements, it is sometimes necessary to remove some content of a signal. This might be due to an interfering source that has to be filtered out, or that only a specific frequency interval is of interest. In such a case, it would be practical if a universal frequency selective filter was available and easy to use. In this thesis, a platform for implementing different frequency selective digital filters is developed. Through a user interface, parameters such as sampling frequency, filter order, type of filter and cutoff frequencies are set by the user. This provides a platform which is easy to configure in order to run one or multiple IIR or FIR filters in various constellations. By combining different filters, a wide variety of frequency responses can be obtained. A prototype is constructed, which allows the user to connect up to two input signals and retrieve up to two output signals. The filter bank is programmed in C and implemented in a 32-bit microcontroller, base on the ARM architecture. To get a reliable prototype, a printed circuit board is designed and manufactured. To protect the electronics from external stress, a cover is designed and 3D-printed.

    The filter design algorithms and the algorithm used when running the filter bank gives satisfying results. The capacity of the filter bank can be increased by refining the filtering algorithm. By improving the hardware, noise generated by the electronics can be decreased. The filter bank has a really good potential to become a very useful tool.

  • 49. Lin, Hao
    et al.
    Xu, Wenyao
    Guan, Nan
    Ji, Dong
    Wei, Yangjie
    Yi, Wang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Noninvasive and continuous blood pressure monitoring using wearable body sensor networks2015Inngår i: IEEE Intelligent Systems, ISSN 1541-1672, E-ISSN 1941-1294, Vol. 30, nr 6, s. 38-48Artikkel i tidsskrift (Fagfellevurdert)
  • 50.
    Lindstål, Tim
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    Marklund, Daniel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    Application of LabVIEW and myRIO to voice controlled home automation2019Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    The aim of this project is to use NI myRIO and LabVIEW for voice controlled home automation. The NI myRIO is an embedded device which has a Xilinx FPGA and a dual-core ARM Cortex-A9processor as well as analog input/output and digital input/output, and is programmed with theLabVIEW, a graphical programming language. The voice control is implemented in two differentsystems. The first system is based on an Amazon Echo Dot for voice recognition, which is acommercial smart speaker developed by Amazon Lab126. The Echo Dot devices are connectedvia the Internet to the voice-controlled intelligent personal assistant service known as Alexa(developed by Amazon), which is capable of voice interaction, music playback, and controllingsmart devices for home automation. This system in the present thesis project is more focusingon myRIO used for the wireless control of smart home devices, where smart lamps, sensors,speakers and a LCD-display was implemented.

    The other system is more focusing on myRIO for speech recognition and was built on myRIOwith a microphone connected. The speech recognition was implemented using mel frequencycepstral coefficients and dynamic time warping. A few commands could be recognized, includinga wake word ”Bosse” as well as other four commands for controlling the colors of a smart lamp.

    The thesis project is shown to be successful, having demonstrated that the implementation ofhome automation using the NI myRIO with two voice-controlled systems can correctly controlhome devices such as smart lamps, sensors, speakers and a LCD-display.

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