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  • 1.
    Abboud, Mohamad Moulham
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energivetenskap.
    Simulation of 3ph induction motor in Matlab with VVVF starting method2016Självständigt arbete på avancerad nivå (magisterexamen), 40 poäng / 60 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Numera är tre-fas asynkronmotorer i stor utsträckning på industriella och andra typer av processer. Därför är det mycket viktigt att ha exakt kunskap om en induktionsmotorprestanda för att ha en uppfattning om dess driftsförhållanden . Denna studie är en fortsättning av en tidigare, där direkt och mjukstart metoder för trefasmotorer har simulerats och jämförts. Såsom i den tidigare studien, är teorin bakom denna en baserat på representerar den verkligamotorn av en uppsättning ekvationer och värden i Matlab, som bildar en motsvarande ideell motor på ett sätt där alla de fysiska effekterna är likartade . Motorn startas under tre olika frekvenser i VVVF metod med stöd simulering av ström, vridmoment, hastighet, effektivitetoch effektfaktorn kurvor. Därefter, resultaten av de tre startmetoder diskuteras och jämföras.

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  • 2.
    Abuella, Mohamed
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Centrum för forskning om tillämpade intelligenta system (CAISR).
    Atoui, M. Amine
    Högskolan i Halmstad, Akademin för informationsteknologi, Centrum för forskning om tillämpade intelligenta system (CAISR).
    Nowaczyk, Sławomir
    Högskolan i Halmstad, Akademin för informationsteknologi, Centrum för forskning om tillämpade intelligenta system (CAISR).
    Johansson, Simon
    CetaSol AB, Gothenburg, Sweden.
    Faghani, Ethan
    CetaSol AB, Gothenburg, Sweden.
    Data-Driven Explainable Artificial Intelligence for Energy Efficiency in Short-Sea Shipping2023Ingår i: Machine Learning and Knowledge Discovery in Databases: Applied Data Science and Demo Track: European Conference, ECML PKDD 2023, Turin, Italy, September 18–22, 2023, Proceedings, Part VII / [ed] Gianmarco De Francisci Morales; Claudia Perlich; Natali Ruchansky; Nicolas Kourtellis; Elena Baralis; Francesco Bonchi, Cham: Springer, 2023, Vol. 14175, s. 226-241Konferensbidrag (Refereegranskat)
    Abstract [en]

    The maritime industry is under pressure to increase energy efficiency for climate change mitigation. Navigational data, combining vessel operational and environmental measurements from onboard instruments and external sources, are critical for achieving this goal. Short-sea shipping presents a unique challenge due to the significant influence of surrounding landscape characteristics. With high-resolution onboard data increasingly accessible through IoT devices, appropriate data representations and AI/ML analytical tools are needed for effective decision support. The aim of this study is to investigate the fuel consumption estimation model’s role in developing an energy efficiency decision support tool. ML models that lacking explainability may neglect important factors and essential constraints, such as the need to meet arrival time requirements. Onboard weather measurements are compared to external forecasts, and our findings demonstrate the necessity of eXplainable Artificial Intelligence (XAI) techniques for effective decision support. Real-world data from a short-sea passenger vessel in southern Sweden, consisting of 1754 voyages over 15 months (More of data description and code sources of this study can be found in the GitHub repository at https://github.com/MohamedAbuella/ST4EESSS), are used to support our conclusions.  © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

  • 3.
    Adnan Abdu, Jihad
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Lundström, Philip
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Water Quality Device: Testing Through Electronic Measurements2023Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Vatten är grunden till allt liv, men tyvärr blir vattenkvaliteten bara sämre på grund av många faktorer som överanvändning, förorening, likgiltighet och till och med av naturen själv. Genom att identifiera problemet är vi ett steg närmare att lösa problemet, och detta är därför en intelligent vattenkvalitetsenhet behövs för att undersöka vattnet och hitta orenheter i det. I detta projekt utvecklar vi en apparat som använder en helt ny metod för att mäta vattenkvaliteten. Även om teorin bakom apparaten är väldigt avancerad så är apparaten fortfarande primitiv i sina funktioner och behöver utveckling för att öka användbarheten och noggrannheten i mätningarna!

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  • 4.
    Aftab, Mohammad Adnan
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Biofuel, An alternative source for jet fuel in Aviation2017Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The transport industry is one of the fastest growing industries with the sector playing a significant role in negative impact on global warming and pollution through the emission of greenhouse gases. Aviation in particular, has enjoyed growth especially in the few decades. New airlines and aircraft manufacturers are coming up with different innovations and technologies to ensure they make the best possible environmentally friendly aircraft. The new main area of focus has been on how to come up with fuel that will reduce the greenhouse gas-emissions. The stakeholders in the same effort include developed nations like the United States, United Kingdom, Russia, France, Germany, and Canada among others. Energy providers as well as jet fuel suppliers are also making efforts to conserve the environment. The purpose of this thesis is to explore the area of biofuel in aviation by looking into various stakeholders involved in the efforts of the transition from fossil fuel to biofuel. The conclusion of this thesis is that biofuels are viable options in the aviation industries since there have been positive results in the tests made. 

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  • 5.
    Ahlbäck, David
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    KONCEPTANALYS OCH DRIFTFALLSOPTIMERING AV "FREEPOWER – SOLAR BOAT"2019Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This report aims to analyse the concept of Bjurtech AB:s ongoing development project “Freepower - Solar Boat”. Main focuses are technical optimization and usability from an end user perspective. Bjurtechs idea is to build an electric-powered 5-meter boat charged by integrated photovoltaic cells. The project´s intended pilot market is Sri Lankas coastal fishing fleet. A version for the Scandinavian market is also under consideration and both concepts are analysed in this report. Initially a 4.5-meter prototype was built and tested to try the concept in practise. Methods used are computer simulations in Matlab based on data collected from trail runs with the prototype combined with weather data from Sri Lanka and Sweden. The data and simulations were then used to try to determine whether the concept works for the intended target markets, as well as how the assumed user profiles affect usability and technical deterioration such as battery life. The approach used was to try to determine how to maximize the availability of the system in regards to battery charge level over the whole year at the same time as maximizing distance and boat speed per day. The systems CO2 emissions were then compared to an equivalent petrol-powered boat with the same amount of running hours over 25 years. The main findings of the study are, provided 12 to 14.5 nautical miles is regarded as a sufficient daily distance at 3 to 3.7 knots boat speed, that the system can deliver a high level of availability all year around for fishing operations in Sri Lanka. Considering the demand for daily availability is not as high for the assumed recreational use in Scandinavian markets the system is deemed to perform at a satisfactory level at these latitudes as well. The CO2 comparison showed a significant emissions decrease in the case of year around operations in Sri Lanka. In Scandinavia a reduction is obtained if there are a sufficient amount of operating hours per year. An increase of the installed rated power, Wp, was found to be the most cost efficient way of improving overall performance and that the prototypes photovoltaics of 580 Wp should in both the Sri Lankan and Scandinavian case be increased to a minimum of 800 Wp. Finally it was concluded that user awareness of how system operation impacts battery life can be of significant importance for a positive environmental result and long technical lifetime.

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  • 6.
    Ahmed, Rizwan
    et al.
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Abbas, Shahid
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Electrical and Optical Characteristics of InP Nanowires based p-i-n Photodetectors2010Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Photodetectors are a kind of semiconductor devices that convert incoming light to an electrical signal. Photodetectors are classified based on their different structure, fabrication technology, applications and different sensitivity. Infrared photodetectors are widely used in many applications such as night vision, thermal cameras, remote temperature sensing, and medical diagnosis etc.

     

    All detectors have material inside that is sensitive to incoming light. It will absorb the photons and, if the incoming photons have enough energy, electrons will be excited to higher energy levels and if these electrons are free to move, under the effect of an external electric field, a photocurrent is generated.

     

    In this project Fourier Transform Infrared (FT-IR) Spectroscopy is used to investigate a new kind of photodiodes that are based on self-assembled semiconductor nanowires (NWs) which are grown directly on the substrate without any epi-layer. The spectrally resolved photocurrent (at different applied biases) and IV curves (in darkness and illumination) for different temperatures have been studied respectively. Polarization effects (at low and high Temperatures) have been investigated.  The experiments are conducted for different samples with high concentration of NWs as well as with lower concentration of NWs in the temperature range from 78 K (-195ºC) to 300 (27ºC). These photodiodes are designed to work in near infrared (NIR) spectral range.

     

    The results show that the NW photodetectors indeed are promising devices with fairly high break down voltage, change of photocurrent spectra with polarized light, low and constant reverse saturation current (Is). The impact of different polarized light on photocurrent spectra has been investigated and an attempt has been made to clarify the observed double peak of InP photocurrent spectrum. Our investigations also include a comparison to a conventional planar InP p-i-n photodetector.

     

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  • 7.
    Akbari, Maryam
    et al.
    Iran University of Science and Technology, Tehran, Iran.
    Mirzakuchaki, Sattar
    Iran University of Science and Technology, Tehran, Iran.
    Fazeli, Mahdi
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Tarihi, Mohammad Reza
    Niroo Research Institute, Tehran, Iran.
    Pure Magnetic Memory-Based PUFs: A Secure and Lightweight Solution for IoT Devices2023Ingår i: Iranian Journal of Electrical and Electronic Engineering, ISSN 2383-3890, Vol. 19, nr 4, artikel-id 2944Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In light of the growing prevalence of Internet of Things (IoT) devices, it has become essential to incorporate cryptographic protection techniques for high-security applications. Since IoT devices are resource-constraints in terms of power and area, finding cost-effective ways to enhance their security is necessary. Physical unclonable function (PUF) is considered a trusted hardware security mechanism that generates true and intrinsic randomness by extracting the inherent process variations of circuits. In this paper, a novel pure magnetic memory-based PUF is presented. The fundamental building blocks of the proposed PUF design are magnetic devices, the so-called mCells. These magnetoresistive devices exclusively utilize Magnetic Tunnel Junction (MTJ) components. Using purely MTJ in the main memory and sense amplifier in the proposed PUF leads to high randomness, high reliability, low power, and ultra-compact occupation area. The Monte Carlo HSPICE simulation results demonstrate that the proposed PUF achieves a uniqueness of 49.89%, uniformity of 50.02 %, power consumption of 1.43 µW, and an area occupation of 0.01 µm2 per bit. © 2023, Iran University of Science and Technology. All rights reserved.

  • 8.
    Akbari, Maryam
    et al.
    Iran University of Science and Technology, Tehran, Iran.
    Mirzakuchaki, Sattar
    Iran University of Science and Technology, Tehran, Iran.
    Jamshidi, Vahid
    Shahid Bahonar University of Kerman, Kerman, Iran.
    Fazeli, Mahdi
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Tarihi, Mohammad Reza
    Niroo Research Institute (NRI), Tehran, Iran.
    An Ultra-compact Pure Magnetic Arbiter PUF with High Reliability and Low Power Consumption2023Ingår i: IEEE transactions on nanotechnology, ISSN 1536-125X, E-ISSN 1941-0085, Vol. 22, s. 449-456Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Due to the rugged environmental factors in IoT applications and constrained on-chip resources, PUF, as a critical hardware primitive, is a promising solution for key storage, authentication, and ID generation. The existing CMOS-based Arbiter PUFs mainly suffer from low reliability and vulnerability against modeling attacks. In this paper, the proposed PUF utilizes mCell devices, a class of Magnetoresistive devices employing only Magnetic Tunnel Junction (MTJ) devices, as a building block. Also, a novel nonvolatile latch is proposed to act as an arbiter and generates the responses by comparing the current values instead of delays which leads to increased the reliability by subtracting the constant variation rates of MTJs under environmental variation without adding hardware overhead. The characteristics of MTJ like nonvolatility, stochastic switching, chaotic magnetization, low power consumption, and low occupied area have made the proposed PUF to a low power, highly reliable, high randomness and ultra-compact pure magnetic arbiter PUF. The Monte Carlo HSPICE simulation results reveal that the uniformity, uniqueness, bit-aliasing, power consumption, and area of the proposed PUF are 49.24 %, 49.87 %, 48.64 %, 10.771 μW and 0.106 μm2, respectively. In addition, the average BER across a wide temperature range (-50C 150C) and voltage range (0.05 V-0.1 V) is 0.08 % and 0.18 %, respectively. © IEEE

  • 9.
    Alhamarna, Ahmed
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Kjellgren, Simon
    Högskolan i Halmstad, Akademin för informationsteknologi.
    IDENTIFIERING AV ELEKTRONIKSKROT2017Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Denna rapport a ̈r resultatet av en underso ̈kning gjord p ̊a bega ̈ran av ett ̊ater- vinningsfo ̈retag, vars o ̈nskan var att unders ̈oka mo ̈jligheter f ̈or att effektivisera sorteringsprocessen av elektroniskt skrot i deras ̊atervinningslokal. Metoden som underso ̈ks a ̈r om RFID skulle kunna anv ̈andas f ̈or identifiering av skrotet. Projektmedlemmarna bo ̈rjade sitt arbete med att unders ̈oka om RFID var den b ̈asta identifieringsmetoden, d ̈ar f ̈or och nackdelar med olika automatiska identifikationssystem ja ̈mf ̈ordes. Slutsatsen av arbetet var att RFID skulle kunna vara en h ̊allbar lo ̈sning i framtiden fo ̈rutsatt att elektronikproducen- ter integrerar RFID taggar i sina produkter. Med tanke p ̊a att fler och fler producenter anva ̈nder RFID fo ̈r att lokalisera och identifiera sina produkter under tillverkning och det sjunkande priset p ̊a passiva taggar, ̈ar det mo ̈jligt att RFID-ma ̈rkning av produkter skulle kunna bli en standard i framtiden, b ̊ade f ̈or effektivare logistik och f ̈or en effektivare ̊atervinningsprocess. 

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  • 10.
    ALRimawi, Mohammed
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Doppler Wheel for Emulation of Automotive Radar Target2019Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Automotive radar is an emerging field of research and development. Technological ‎advancements in this field will improve safety for vehicles, pedestrians, and ‎bicyclists, and enable the development of autonomous vehicles. Usage of the ‎Automotive radar is expanding ‎in car and road areas to reduce collisions and ‎accident. Automotive radar ‎developers face a problem to test their radar sensor in ‎the street since there are a lot of interferences ‎signals, noise and unpredicted ‎situations. This thesis provides a part of the solution for this problem by designing a ‎device can demonstrate a different speeds value. This device will help the developer ‎to test their radar sensor inside an anechoic chamber room that provides accurate ‎control of the environmental conditions. This report shows how to ‎build the ‎measuring setup device, step by step to demonstrate the people and vehicle’s speed ‎‎in the street by a Doppler emulator using the wheel for millimetre FWMC radar. ‎Linear speed system needs a large space for testing, but using the rotational wheel ‎allow the developer to test the radar sensor in a small area. It begins with the wheel ‎design specifications and the relation between the ‎rotational speed (RPM) of the ‎wheel and the Doppler frequency. The Doppler ‎frequency is changed by varying the ‎speed of the wheel. Control and power circuit ‎was carefully designed to control the ‎wheel speed accurately. All the measuring ‎setup device parts were assembled in one ‎box. Also, signal processing was done by ‎MATLAB to measure the Doppler frequency ‎using millimetre FMCW radar sensor. ‎The measuring setup device was tested in the ‎anechoic chamber room for different speeds. the ‎manual and automatic tests show ‎good results to measure the different wheel speeds ‎with high accuracy.‎

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    Automotive Testing result
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    Circuit board (OrCAD files)
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    C programming file (mikroC)
  • 11.
    Alvarado, Cristian
    et al.
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Ibrahim, Ayad
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Fjärrstyrning av videokamera2012Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    On some occasions it may be inappropriate with a cameraman behind the camera. In somecases there is no cameraman available or it is a smaller event, like a family celebration, to befilmed. It can also be difficult for a cameraman to shoot from certain angles. One solution forthis kind of situations can be to remotely control the camera movements. There are thosekinds of solutions on the market today but they either address professional filmmakers or thefunctionality is limited, for example by the absence of wireless remote control.This project aims to develop a solution to the problem with absence of wireless remote controland also a solution with more flexibility and less complexity than today’s solutions. The maindifference between this and existing solutions is the use of Bluetooth technology ascommunication between the devices. The project resulted in a solution consisting of twounits; one operating unit where the camera is mounted and a remote unit for control of theoperating unit. The remote unit is managed by the filmmaker. The remote unit consist of anAndroid application on a smart and which communicates with the control unit via Bluetooth.

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  • 12.
    Amador Molina, Oscar
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Soto, Ignacio
    Departamento de Ingeniería de Sistemas Telemáticos, ETSI Telecomunicación, Universidad Politécnica de Madrid, Madrid, Madrid, 28040, Spain.
    Calderon, Maria
    Departamento de Ingeniería Telemática; Universidad Carlos III de Madrid, Madrid, Leganés, 28911, Spain.
    Urueña, Manuel
    Escuela Superior de Ingenieros y Tecnología, Universidad Internacional de la Rioja, La Rioja, Logroño, 26006, Spain.
    Studying and improving the performance of ETSI ITS contention-based forwarding (CBF) in urban and highway scenarios: S-FoT+2023Ingår i: Computer Networks, ISSN 1389-1286, E-ISSN 1872-7069, Vol. 233, artikel-id 109899Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper evaluates the performance of ETSI ITS Contention-Based Forwarding (CBF) and ETSI Simple GeoBroadcast forwarding while disseminating warning messages over a Geographical Area in highway and urban scenarios. Our experimental evaluation considers the complete ETSI ITS architecture including the Decentralized Congestion Control (DCC) mechanism. We propose an enhanced CBF mechanism, named S-FOT+, which combines several improvements to the ETSI CBF algorithm. S-FoT+ has a similar or better performance than the ETSI forwarding algorithms regarding both reliability and end-to-end delay while requiring much fewer transmissions. The improvements are equally effective and efficient in both urban and highway scenarios with large Destination Areas. Finally, we evaluate the trade-offs that stem from using multi-hop broadcast mechanisms in urban settings with smaller Destination Areas when compared to single-hop broadcast. Results show that multi-hop mechanisms significantly improve coverage at the cost of an increased number of transmissions. © 2023 The Author(s)

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  • 13.
    Amin, Mohammed Nurul
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi. amin _ m 154@yahoo.com.
    Alam, Md. Obaidul
    Högskolan i Halmstad, Akademin för informationsteknologi. obai_ aust@yahoo.com.
    Landin, Lars
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Tillämpad matematik och fysik (MPE-lab).
    Electrical and optical characteristics of Infrared Photodetectors based on InP nanowire2011Ingår i: 14th International Conference on Computer and Information Technology, ICCIT 2011, s. 629-634, artikel-id 6164864Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    High speed photodetectors are most sophisticated optoelectronic devices, because it has high photo sensitivity, and allow a large wavelength range of detection as a receiver from 750 nm to 1.3-1.55 μm in the optical communication system. Since the last decade, the electrical and optical characteristics of photodetectors have been investigated to improve their performance and price. We have worked on two different type of infrared photodetectors based on nanowire. One photodetector was p-n photodiode, and the other one was p-i-n structure. We investigated the detector performance at 77K-300K temperature corresponding with wavelength in darkness and under illumination as regarding breakdown voltage, sensitivity, and quantum efficiency. We have also compared the differences between the two photodetectors performance characteristics. © 2011 IEEE.

  • 14.
    Amin, Muhammed Nurul
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi. amin_m154@yahoo.com.
    Alam, Md. Obaidul
    Högskolan i Halmstad, Akademin för informationsteknologi. obai_aust@yahoo.com.
    Electro-optical characterisation of inp nanowire based p-n, p-i-n infrared photodetectors2012Ingår i: Journal of Communications, ISSN 1796-2021, E-ISSN 2374-4367, Vol. 7, nr 11, s. 808-820Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    High speed photodetectors are most sophisticated optoelectronic devices, because it has high photo sensitivity, low noise, high conversion efficiency and allow a large wavelength range of detection from 750 nm to 1.3-1.55 pm in the optical communication system. These photodetector is used as an optical receiver which transforms the energy of optical radiation such as infrared, visible or ultraviolet into the electrical signal that is convenient for measurement. Since the last decade, the electro-optical characterisation of photodetectors has been investigated to improve their performance and price. In this paper, we are going to discuss the characterisation of the two different type infrared photodectors based on nanowire that we have worked on our project. One photodetector is p- n nanowire structure, and another is p-i-n structure. Both photodetectors is worked based on internal photoelectric effect and on the theory of p-n junction. We investigated the detector performance at 77K-300K temperature corresponding with wavelength in darkness and under illumination as regarding breakdown voltage, sensitivity, and quantum efficiency. We have also compared the differences between the two photodetectors performance characteristics. © 2012 ACADEMY PUBLISHER.

  • 15.
    Andersen, Niklas
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Ismail, Zahir
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Solel från ljudbarriär: längs Annetorpsvägen i Hyllie, Malmö2014Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    City of Malmö has ambitions for the district Hyllie to become a demonstrative area ofsustainable urban development. As a part of this the following report aims to investigate the potential in using noise barriers combined with photovoltaics along Annetorpsvägen to generate solar electricity. To quantify the losses that shadows from buildings along the roadmight cause, a 3D-model of the area was constructed in SketchUp. This digital model made it possible to simulate shadows and how they change over the year. A reference model of a photovoltaic noise barrier (PVNB) was constructed and used to find the dates on which the solar cells are shadowed depending on building heights and positioning of the barrier.

    The results show that two lengths with a total distance of 400 meters is appropriate for applying photovoltaic noise barriers. Along distance A, a PVNB with a total capacity of 19 kWp is expected to generate 18 000 kWh per year assuming realistic shadowing, which equals 6% losses compared to production without shadows. The PVNB along distance B with installed capacity of 37 kWp has no considerable problems with shadowing and is expected to generate 37 500 kWh per year. This gives a total production of 56 500 kWh per year.

    The combined investment costs (excluding costs for the actual noise barrier) for both power plants are assumed to be approximately one million SEK. Expected economical outcome is a negative capital value after 25 years, although a change of critical factors such as investment aid, investment cost, electricity prices and cost of capital may result in a more positive outcome. Production losses from shadowing and dirt seem to have a minimal effect on the outcome

    Despite uncertainty in the economical outcome, realizing the project would have several other positive effects such as reduction of carbon dioxide emissions and a positive impact on the public view of renewable energy.

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  • 16.
    Andersson, Gustav
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Ericsson, Emil
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Dark Ages Interferometer (DALI) Deployment Rover: Energy System2014Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I kosmologi kallas epoken mellan “rekombinationen till väte” och bildandet av de första stjärnorna för “den mörka tidsåldern”. Från denna tid finns endast spår i form av strålning från neutralt väte. Denna strålning kan enligt astronomer vara en viktigare källa till data om universums uppkomst än den kosmiska mikrovågsstrålningen. Därför arbetar NASA/JPL med att hitta metoder att observera denna rika källa till data. Den mest använda metoden är att använda lågfrekventa radioteleskop för att observera strålning med våglängder mellan 3-30 m och frekvenser mellan 10-100 Mhz. Ett stort problem med så kort strålning är den lätt störs ut av mänsklig påverkan och andra radiokällor, tillexempel solen. Ett sätt att undvika antropogen störning är att bygga ett radioteleskop på månens baksida. Eftersom månen är i en låst bana runt jorden vänder den alltid samma sida bort från planeten. Därför är platsen alltid i radioskugga från jorden ochstörs inte av mänsklighetens radiotrafik. JPL har lång erfarenhet av användandet av robotfarkoster för att utforska himlakroppar. År 2030 vill de sända en så kallad rover för att upprätta en grupp radioteleskop på månen med syftet att införskaffa data om “den mörka tidsåldern.” Högskolan i Halmstad erbjuder sedan 2013 studenter möjligheten att skriva sitt examensarbete i samarbete med NASA/JPL om konstruktionen av denna rover. Detta arbete har ämnat finna en lösning på rovens energiförsörjning genom att använda solceller och batterier. Slutsatsen har varit att det är möjligt att driva en rover på månen med solceller samt batterier. Ett krav är att rovern värms med radioisotoperunder natten för att minska energianvändningen.

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    DALI Energy System
  • 17.
    Andersson, Robin
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    Electric power quality in low voltage grid: Office buildings and rural substation2015Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The modern society uses more and more electronic devices needed to being able to function together. This put higher demands on the electrical grid together with that the typical load have changed from the past. Therefore utility companies are obliged to keep the voltage within certain limits for this to function. What exact these limits have been have not always been clear since they have not been gathered in one single document. 

    This thesis is a cooperation with Kraftringen who also has been the initiator. Kraftringen would like to become more proactive in their work regarding electric power quality. For becoming more proactive continuously measurements have to be done but the locations have to be carefully selected in the beginning to get a wider perspective of the grid.

    Energy markets inspectorate (EI) is supervisory of the electric power quality in Sweden and since 2011 they have published a code of statutes (EIFS 2011:2 later 2013:1) intended to summarize limits on voltage. Some of the electrical power quality aspects are not mentioned in EIFS 2013:1 and standards have to be used to find limited values. Flicker and interharmonics are not mentioned in EIFS 2013:1 and for values on flicker the standard SS-EN 50160 has to be used and for interharmonics the standard SS-EN 61000-2-2 state limit values. Besides all this there are standards with stricter limits than EIFS 2013:1 e.g. for total harmonic distortion on voltage were SS-EN 61000-2-2 suggest 6 % instead of 8 %.

    Three different field studies have been conducted in order to get some perception of the present situation regarding electric power quality. Two measurements were conducted on a typical office building because they represents a large part of the typical load in Lund. The third measurement was conducted on a substation in a rural area to get a perception of the situation outside urban areas. 

    These measurements shown that the overall electric power quality was within given limits according to EIFS 2013:1 and different standards. However, conducted measurements shown some interesting results. Both the typical office buildings have a slightly capacitive power factor which results in that the voltage inside the building is going to be slightly higher than at the substation. Since the voltage level at the measured urban substation was above nominal voltage level with about 2-5 % this could be problematic. Another eventual problem with a load with a capacitive power factor is resonance with the inductive parts of the grid like transformers leading to magnified harmonic levels.

    It is suggested that Kraftringen expand their number of permanent electric power quality measurement locations to get a better overview of the present situation. The best suited locations to start with are such that have received complaints earlier, preferably measured on the low voltage side of the transformer for also register the amount of zero sequence harmonics. Next step in the measurement expansion would be substations known to be under higher load than others or substations with a PEN-conductor in a smaller area than the phase conductors, supplying a typical office load with high amounts of third harmonics and unbalance. From this it would be appropriate to spread out the measurement locations geographically to better get to know the grids behaviour. 

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  • 18.
    Aramrattana, Maytheewat
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES). The Swedish National Road and Transport Research Institute (VTI), Göteborg, Sweden.
    A Simulation-Based Safety Analysis of CACC-Enabled Highway Platooning2018Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Cooperative Intelligent Transport Systems (C-ITS) enable actors in the transport systems to interact and collaborate by exchanging information via wireless communication networks. There are several challenges to overcome before they can be implemented and deployed on public roads. Among the most important challenges are testing and evaluation in order to ensure the safety of C-ITS applications.

    This thesis focuses on testing and evaluation of C-ITS applications with regard to their safety using simulation. The main focus is on one C-ITS application, namely platooning, that is enabled by the Cooperative Adaptive Cruise Control (CACC) function. Therefore, this thesis considers two main topics: i) what should be modelled and simulated for testing and evaluation of C-ITS applications? and ii) how should CACC functions be evaluated in order to ensure safety?

    When C-ITS applications are deployed, we can expect traffic situations which consist of vehicles with different capabilities, in terms of automation and connectivity. We propose that involving human drivers in testing and evaluation is important in such mixed traffic situations. Considering important aspects of C-ITS including human drivers, we propose a simulation framework, which combines driving-, network-, and traffic simulators. The simulation framework has been validated by demonstrating several use cases in the scope of platooning. In particular, it is used to demonstrate and analyse the safety of platooning applications in cut-in situations, where a vehicle driven by a human driver cuts in between vehicles in platoon. To assess the situations, time-to-collision (TTC) and its extensions are used as safety indicators in the analyses.

    The simulation framework permits future C-ITS research in other fields such as human factors by involving human drivers in a C-ITS context. Results from the safety analyses show that cut-in situations are not always hazardous, and two factors that are the most highly correlated to the collisions are relative speed and distance between vehicles at the moment of cutting in. Moreover, we suggest that to solely rely on CACC functions is not sufficient to handle cut-in situations. Therefore, guidelines and standards are required to address these situations properly.

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  • 19.
    Aramrattana, Maytheewat
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES). The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Modelling and Simulation for Evaluation of Cooperative Intelligent Transport System Functions2016Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Future vehicles are expected to be equipped with wireless communication tech- nology, that enables them to be “connected” to each others and road infras- tructures. Complementing current autonomous vehicles and automated driving systems, the wireless communication allows the vehicles to interact, cooperate, and be aware of its surroundings beyond their own sensors’ range. Such sys- tems are often referred to as Cooperative Intelligent Transport Systems (C-ITS), which aims to provide extra safety, efficiency, and sustainability to transporta- tion systems. Several C-ITS applications are under development and will require thorough testing and evaluation before their deployment in the real-world. C- ITS depend on several sub-systems, which increase their complexity, and makes them difficult to evaluate.

    Simulations are often used to evaluate many different automotive appli- cations, including C-ITS. Although they have been used extensively, simulation tools dedicated to determine all aspects of C-ITS are rare, especially human fac- tors aspects, which are often ignored. The majority of the simulation tools for C-ITS rely heavily on different combinations of network and traffic simulators. The human factors issues have been covered in only a few C-ITS simulation tools, that involve a driving simulator. Therefore, in this thesis, a C-ITS simu- lation framework that combines driving, network, and traffic simulators is pre- sented. The simulation framework is able to evaluate C-ITS applications from three perspectives; a) human driver; b) wireless communication; and c) traffic systems.

    Cooperative Adaptive Cruise Control (CACC) and its applications are cho- sen as the first set of C-ITS functions to be evaluated. Example scenarios from CACC and platoon merging applications are presented, and used as test cases for the simulation framework, as well as to elaborate potential usages of it. Moreover, approaches, results, and challenges from composing the simulation framework are presented and discussed. The results shows the usefulness of the proposed simulation framework.

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  • 20.
    Aramrattana, Maytheewat
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES). The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Larsson, Tony
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Jansson, Jonas
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Nåbo, Arne
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    A simulation framework for cooperative intelligent transport systems testing and evaluation2019Ingår i: Transportation Research Part F: Traffic Psychology and Behaviour, ISSN 1369-8478, E-ISSN 1873-5517, Vol. 61, s. 268-280Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Connected and automated driving in the context of cooperative intelligent transport systems (C-ITS) is an emerging area in transport systems research. Interaction and cooperation between actors in transport systems are now enabled by the connectivity by means of vehicle-to-vehicle and vehicle-to-infrastructure (V2X) communication. To ensure the goals of C-ITS, which are safer and more efficient transport systems, testing and evaluation are required before deployment of C-ITS applications. Therefore, this paper presents a simulation framework—consisting of driving-, traffic-, and network-simulators—for testing and evaluation of C-ITS applications. Examples of cooperative adaptive cruise control (CACC) applications are presented, and are used as test cases for the simulation framework as well as to elaborate on potential use cases of it. Challenges from combining the simulators into one framework, and limitations are reported and discussed. Finally, the paper concludes with future development directions, and applications of the simulation framework in testing and evaluation of C-ITS. © 2017 Elsevier Ltd. All rights reserved.

  • 21.
    Aramrattana, Maytheewat
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES). The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Larsson, Tony
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Jansson, Jonas
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Nåbo, Arne
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Cooperative Driving Simulation2016Ingår i: Proceedings of the Driving Simulation Conference 2016, 2016, s. 123-132Konferensbidrag (Refereegranskat)
    Abstract [en]

    For a few decades, driving simulators have been supporting research and development of advanced driver assistance systems (ADAS). In the near future, connected vehicles are expected to be deployed. Driving simulators will need to support evaluation of cooperative driving applications within cooperative intelligent transportation systems (C-ITS) scenarios. C-ITS utilize vehicle-to-vehicle and vehicle-to-infrastructure (V2X) communication. Simulation of the inter vehicle communication is often not supported in driving simulators. On the other hand, previous efforts have been made to connect network simulators and traffic simulators, to perform C-ITS simulations. Nevertheless, interactions between actors in the system is an essential aspect of C-ITS. Driving simulators can provide the opportunity to study interactions and reactions of human drivers to the system. This paper present simulation of a C-ITS scenario using a combination of driving, network, and traffic simulators. The architecture of the solution and important challenges of the integration are presented. A scenario from Grand Cooperative Driving Challenge (GCDC) 2016 is implemented in the simulator as an example use case. Lastly, potential usages and future developments are discussed.

  • 22.
    Aramrattana, Maytheewat
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi. Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Patel, Raj Haresh
    Communication Systems Department, EURECOM, Sophia-Antipolis, France.
    Englund, Cristofer
    Högskolan i Halmstad, Akademin för informationsteknologi. RISE Viktoria, Gothenburg, Sweden.
    Harri, Jerome
    Communication Systems Department, EURECOM, Sophia-Antipolis, France.
    Jansson, Jonas
    Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Bonnet, Christian
    Communication Systems Department, EURECOM, Sophia-Antipolis, France.
    Evaluating Model Mismatch Impacting CACC Controllers in Mixed Traffic using a Driving Simulator2018Ingår i: 2018 IEEE Intelligent Vehicles Symposium (IV), New York, NY: IEEE, 2018, s. 1867-1872Konferensbidrag (Refereegranskat)
    Abstract [en]

    At early market penetration, automated vehicles will share the road with legacy vehicles. For a safe transportation system, automated vehicle controllers therefore need to estimate the behavior of the legacy vehicles. However, mismatches between the estimated and real human behaviors can lead to inefficient control inputs, and even collisions in the worst case. In this paper, we propose a framework for evaluating the impact of model mismatch by interfacing a controller under test with a driving simulator. As a proof-of-concept, an algorithm based on Model Predictive Control (MPC) is evaluated in a braking scenario. We show how model mismatch between estimated and real human behavior can lead to a decrease in avoided collisions by almost 46%, and an increase in discomfort by almost 91%. Model mismatch is therefore non-negligible and the proposed framework is a unique method to evaluate them. © 2018 IEEE.

  • 23.
    Arashlouzadeh, Amir
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Tillämpad matematik och fysik (MPE-lab).
    Surface Roughness Measurment: Multi-bandFrequency Shift Interferometer based onPolarization Measurement2014Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Optical measurement techniques have been gaining ground for their vast applications in industry and scientific purposes. These techniques are beneficial comparing to the mechanical methods. Non-intrusive, robust, high accuracy and small measurement volume are some of the advantages of the optical metrology. However, these approaches are expensive. Interferometry is one of the most prominent principles of these optical measurements. It employs the study of fringe patterns in order to model surface roughness with a high precision up to nano-meter scale. In this thesis, we mainly focus on the multi-band frequency shifting interferometry based on polarization measurement for 3D surface modeling. The system has advantages such as it is very accurate and there is no need of a phase unwrapping algorithm. Like the conventional phase shifting interferometry, four intensity images are recorded for the four polarization states correspondingly and then the images are processed by MATLAB and the final results are provided. In this technique the need for three cameras and offset correction between the cameras has been revised and optimized by using only one camera. In the first setup trial, a fiber optic switch has been used which does not lead to the desired results and then the switch has been removed and the corresponding images are satisfactory.

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  • 24.
    Aslam, Muhammad Shamrooz
    et al.
    School of Automation, Guangxi University of Science and Technology, Liuzhou, P.R. China.
    Tiwari, Prayag
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Pandey, Hari Mohan
    Data Science and Artificial Intelligence, Department of Information and Computing, Bournemouth University, Bournemouth, United Kingdom.
    Band, Shahab S.
    Future Technology Research Center, College of Future, National Yunlin University of Science and Technology, Douliou, Taiwan, Republic of China.
    Observer–Based Control for a New Stochastic Maximum Power Point tracking for Photovoltaic Systems With Networked Control System2023Ingår i: IEEE transactions on fuzzy systems, ISSN 1063-6706, E-ISSN 1941-0034, Vol. 31, nr 6, s. 1870-1884Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study discusses the new stochastic maximum power point tracking (MPPT) control approach towards the photovoltaic cells (PCs). PC generator is isolated from the grid, resulting in a direct current (DC) microgrid that can provide changing loads. In the course of the nonlinear systems through the time-varying delays, we proposed a Networked Control Systems (NCSs) beneath an event-triggered approach basically in the fuzzy system. In this scenario, we look at how random, variable loads impact the PC generator's stability and efficiency. The basic premise of this article is to load changes and the value matching to a Markov chain. PC generators are complicated nonlinear systems that pose a modeling problem. Transforming this nonlinear PC generator model into the Takagi–Sugeno (T–S) fuzzy model is another option. Takagi–Sugeno (T–S) fuzzy model is presented in a unified framework, for which 1) the fuzzy observer–based on this premise variables can be used for approximately in the infinite states to the present system, 2) the fuzzy observer–based controller can be created using this same premises be the observer, and 3) to reduce the impact of transmission burden, an event-triggered method can be investigated. Simulating in the PC generator model for the realtime climate data obtained in China demonstrates the importance of our method. In addition, by using a new Lyapunov–Krasovskii functional (LKF) for combining to the allowed weighting matrices incorporating mode-dependent integral terms, the developed model can be stochastically stable and achieves the required performances. Based on the T-P transformation, a new depiction of the nonlinear system is derived in two separate steps in which an adequate controller input is guaranteed in the first step and an adequate vertex polytope is ensured in the second step. To present the potential of our proposed method, we simulate it for PC generators. © 2022 IEEE.

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  • 25.
    Assarsson, Fredrik
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Nilsson, Felix
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Utredning av övertoners effekter på transformatorer2019Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Detta examensarbete är en utredning om hur en av Halmstad Energi och Miljö Nät ABs transformatorer påverkas av övertoner. Utredningen handlar till största del om hur mycket transformatorns nominella effekt måste skrivas ner. Examensarbetet visar teorin kring både vad som är övertoner, övertoners effekter på transformatorer samt beräkningsmodeller för effektnedskrivning. De metoder som används och jämförs för nedskrivning av transformatoreffekt är faktor K, som beskrivs i SS-EN 50464-3 och K-faktor, som beskrivs i ANSI/IEEE C57.100.

    För att på ett verklighetstroget och ingenjörsmässigt sätt beräkna hur de olika standarderna påverkar transformatorn har tre fall testats.  

    • Övertonernas medelinverkan under en månad, utifrån insamlade mätdata.
    • Övertonernas maximala inverkan under en månad, utifrån insamlade mätdata.
    • Övertonernas inverkan om övertonshalterna ökar i framtiden.

    Resultatet av utredningen visar att transformatorns nominella effekt i fallen där mätdata behandlas bör minskas med ca 6–17% för K-faktor-metoden. För faktor K är de siffrorna ca 2,5–7,5%. Dock visar mätdata från samtliga fallen att belastningsgraden på den testade trans-formatorn är långt under den maximala nedskrivna effekten. Om mängden strömövertoner i framtiden skulle öka är en nedskrivning på 30% av maxeffekten inte orimligt. 

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  • 26.
    Axelsson, Alexander
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Karlsson, Viktor
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Undersökning om likströmmars påverkan på jordfelsbrytare2020Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Denna rapport är ett examensarbete skrivet av studenter på Högskolan i Halmstad som läser elektroingenjörsprogrammet med inriktning elkraftteknik. Examensarbetet beskriver en undersökning av jordfelsbrytare, med fokus på jordfelsbrytare av typ A och hur deras beteende ändras vid närvaro av likströmmar. Rapporten inkluderar dessutom bakomliggande fakta om hur jordfelsbrytare fungerar, jordfel och läckströmmar, komponenter som kan ge upphov till likströmmar i en elektrisk krets samt en beskrivning av farorna kopplade till elektricitet. 

    Mätningarna som presenteras är gjorda under så enkla förhållanden som möjligt genom att använda ett testinstrument med jordfelsbrytartest. Likströmmen och växelströmmen som används kopplas och justeras separat för att få så exakta mätvärden som möjligt.

    Testerna resulterar i att jordfelsbrytare inte slutar fungera direkt när likströmmarna blir för stora, utan att mängden jordfelsström som behövs för att få jordfelsbrytaren att slå ifrån istället höjs. En annan slutsats som dras är att mängden likström som behövs för att det här fenomenet skall uppstå verkar vara betydligt högre än de minimala 6mA som industrin använder sig utav vid beskrivning av typ A jordfelsbrytare och ställer frågan om inte den gränsen är ett dåligt utgångsvärde för när typ A slutar fungera.

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  • 27.
    Barkstedt, Patrik
    et al.
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Bizzarri, Sandro
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Forensisk  analys av smartphones: - fokus på sociala medier2013Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I dagens samhälle är trenden att fler och fler människor införskaffar smartphones för att när som helst kunna vara uppkopplade mot internet. Detta gör att informationen en smartphone hanterar och sparar är viktigare och mer intressant för båda sidorna av lagen. Med denna ökning av smartphones har användandet av applikationer till sociala medier så som facebook ökat.I denna rapport utreds det vad en facebookapplikation lagrar för typ av information efter den har använts och hur pass noga det går att kartlägga vart applikationen har används. För att kunna göra detta krävs först en utredning på vilka sätt de går att hämta ut information ifrån en smartphone. I denna rapport har det alltså utretts huruvida de går att utvinna samma information med hjälp av flera metoder och om de går att uppnå samma resultat med hjälp av en utvinning med de olika metoderna. Vid analys av den utvunna datan visar det sig att applikationen lagrade den intressanta datan i databasfiler. Allt från meddelanden och statusuppdateringar till platsdata sparades i dessa databasfiler, vilket gjorde att enheten gick att kartlägga.

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  • 28.
    Behramaj, Fisnik
    et al.
    Högskolan i Halmstad.
    Albinsson, Daniel
    Högskolan i Halmstad.
    Modern Träningsmaskin2015Självständigt arbete på grundnivå (högskoleexamen), 180 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Detta projekt ämnar lösa problematiken med en användarvänlig träningsmaskin med målet attminska skador bland användarna. Detta ska ske genom att användarna själva inte ska behövaapplicera lösa vikter på en så kallad Smithmaskin. Projektets primära mål är att generera en kraftvia en teknisk lösning för att skapa motstånd på stången som kan användas under t.ex. bänkpress.Projektets syfte är att skapa en säker träningsmaskin ämnad för användare oavsett ålder, kön ellerfysiskt tillstånd. Ett annat mål med projektet är att skapa en prototyp på en redan befintligträningsmaskin men för en mindre kostnad. Metoden som tillämpas för projektet ärprocessbeskrivning, tester och undersökningar inom det kunskapsområde som berör studien.Projektgruppen har inhämtat kunskap och fakta via läroböcker samt vetenskapliga artiklar menockså via diskussioner med universitetsadjunkterna Hans-Erik Eldemark och Thomas Munther föratt sedan tillämpa denna information i arbetet. Projektet resulterade i en modifierad träningsmaskinämnad för att generera vikt via en växelströmsmotor där användaren kan välja vikt med ett intervallpå 5 kg via ett användarvänligt gränssnitt. Slutsatsen visar att projektet är genomförbart, att allahögprioriterade mål i kravspecifikationen uppfyllts samt att resultatet blev som förväntat.

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  • 29. Berg, Jacob
    et al.
    Landin, Niclas
    Kommunikationskort2017Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Raytelligence har utvecklat en radar som kan registrera rörelse och hjärtfrekvens hos människor. Datan från radarn skickas över Universal Serial Bus (USB) till en extern dator. För att produkten ska bli mer användarvänlig krävs en bättre kommunikationslösning. Projektet går ut på att implementera en trådlös kommunikation i form av bluetooth och Wireless Local Area Network (WLAN) som kan skicka datan från radarn trådlöst till en extern dator eller mobil enhet. I rapporten beskrivs de olika metoderna som använts för att åstadkomma den trådlösa kommunikationen. Det beskrivs passande gränssnitt, val av passande kommunikationsmodul, implementering och kalibrering av antenn, val av komponenter och olika sätt att motverka Elektromagnetisk Interferens (EMI) för att få bra förutsättningar för en Elektromagnetisk kompatibilitet (EMC)-certifiering. Resultatet av projektet är en produkt som bygger på kommunikationsmodulen RS9113 och Raytelligence radarkort.

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  • 30.
    Bergholm, Johan
    et al.
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Gallardo, Sascha
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Svensson, Jonny
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Positionering och Spårning av mobila enheter, ur ett IT–forensiskt perspektiv2013Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I dagens Sverige så har de mobila enheterna en självklar plats i våra fickor, likväl som i vårt samhälle och i dess brottslighet, vilket gör att det sedan några år är att anse självklart att de även har en central roll i IT–forensiska utredningar inom våra polismyndigheter. Men vid sidan av konkreta bevis för begångna brott lagrar enheterna dessutom ofta data som kan användas för att spåra enheten, och därmed också dess brukare, över tid, vilket givetvis är av intresse av polismyndigheter men skulle även kunna vara av stort intresse för exempelvis försäkringsbolag och andra delar av den 'civila sektorn' som driver utredningar men som saknar polisens befogenheter. För att ge ett så brett användningsområde som möjligt fokuserar därför rapporten inte bara på datat som är tillgängligt från den faktiska enheten och hur de kan användas för spårning och positionering, utan försöker även på praktiskt väg undersöka i vilken grad dessa metoder kan utföras med allmänt tillgänglig mjuk- och hårdvara.

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  • 31.
    Borg, Richard
    et al.
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Svensson, Timmy
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Assistansrobot "Slangaren"2011Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Projektet är ett steg mot att automatisera brandbekämpning. Målet är att minimera personskador genom att ersätta brandmän med robotar och andra tekniska hjälpmedel. Framförallt i farliga miljöer där det finns risk för t.ex. explosioner eller ras. Robotarna är lätta att ersätta och kan manövreras säkert på behörigt avstånd. Idén kommer från företaget Drones Networking som strävar efter att ta fram ett autonomt brandsläckningssystem. Resultatet av projektet är en prototyp av en robot som ska sköta slanghanteringen vid brandbekämpningen.

    Ladda ner fulltext (pdf)
    Examensrapport Assistansrobot
  • 32.
    Borgström, Roger
    et al.
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Enesten, Daniel
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Uv-ljus som vattenrening i kylanläggning2012Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I det här projektet har uppgiften varit att rena vattnet i Aqua Interiör i Laholms egen tillverkade vattenmöbel med hjälp av uv-ljus. Dessa möbler hyr de ut till kunder för att kunna få ett lagom kallt vatten med eller utan kolsyra. Vattenmöblerna är direkt kopplade till det befintliga vattensystemet. Ett problem som de tidigare haft är att de inte kunnat ha sina möbler på sjukhus eftersom möblens beskaffenhet medför en ökad bakteriehalt i vattnet.Denna bakteriehalt kommer dock inte upp till den gräns som livsmedelverkets satt som icke tjänligt. På sjukhus finns ett högre krav på vattnets kvalité där inga anmärkningar får finnas på vattnet. Vid uv-bestrålning hoppas man att detta problem kommer att lösas.Det har tagits fram en reaktor där vattnet uv-bestrålas i en spiral gjord av kvartsglas. Ett styrkort har tagits fram för att styra bestrålningen av vattnet och att ha kontroll på att inga problem med bestrålningen uppkommer.En display med touchfunktion har använts för att på ett snyggt sett presentera viktig information om lampans status och temperatur inne i reaktorn. Detta för att serviceman på vattenmöbeln ska få information på om lampan behöver bytas eller inte. En inloggning i systemet skapades för att förvissa sig om att inga obehöriga skulle ha möjlighet att radera den loggdata som skapas. Med touchdisplayen har man fått en gedigen känsla av kvalite och ny teknik.Användningen av detta uv-filter har resulterat i att vattnet har renats med ett positivt resultat. Förhoppningen är att en vidare utveckling på det här projektet kommer leda till en färdig produkt som kommer säljas/uthyras av Aqua Interiör i Laholm.

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  • 33.
    BOZKURT, Ugur
    et al.
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Aslan, Mustafa
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Assembly of a UAV: hardware design of a UAV2009Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This bachelor thesis is dedicated to assemble the hardware system of a UAV (Unmanned Aerial Vehicle) in order to prepare the platform for an autonomous flight in the air for a given path through the pre-programmed check points. A UAV is an aircraft that contains sensors, GPS, radio system, servomechanisms and computers, which provide the capability of an autonomous flight without a human pilot in the cockpit. A stable flight requires sensing the roll, pitch, and yaw angles of aircraft. Roll and pitch angles were ensured by a sensor system of FMA Direct Company called co-pilot flight stabilization system (CPD4), which allows controlling ailerons and elevator manually.

    An autopilot is required for steering the aircraft autonomously according the GPS data and the establish waypoints that the airplane have to pass by. The GPS gives heading information to the autopilot, and this uses the information of the next waypoint to decide which direction to go. Hereby an autonomous flight is provided. In this project a lego mindstorm NXT was used as an autopilot that is product of LEGO Company [1]. The output of the autopilot is used to control the airplane servos to fly in the desired direction. A software and hardware interface was designed to allow the autopilot to receive the data from the co-pilot sensor and to transmit data to the co-pilot processor, which will finally steer the actuator servos. Experiments were performed with different parts of the system and the results reported.

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    FULLTEXT01
  • 34.
    Bukht, Ali
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Non-Planar 3D Printed Radar Lenses2021Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The primary motivation behind this research was to determine whether 3D printed lenses printed out using the non-planar technique can help achieve better beam intensity for a 60 GHz printed-circuit-board based radar and consequently improve radar efficiency. Non-planar printing is a new development in the 3D printing industry. In the non-planar printing method, the printer is moving simultaneously in all X, Y and Z-axis. This process prints with curved layers, which helps achieve a smoother surface. For this, a newly developed version of the Slic3r, specifically called non-planar Slic3r, was used. The modelled lens was imported into this Slic3r software. The G-Code was generated, and using it, non-planar lenses were printed along with planar lenses for comparison purpose. The lenses printed out using the non-planar technique were not perfectly smooth as was thought initially. Both planar and non-planar lenses measurements were taken in a watchful environment, and the measurements were later compared. The comparison of measurements showed that the non-planar lens did not show any noticeable gain in the intensity over planar lenses. The conclusion, however, is limited to the frequency range around 60 GHz, and in the case of higher frequencies, the result may change

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  • 35.
    Calikus, Ece
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Nowaczyk, Sławomir
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Pinheiro Sant'Anna, Anita
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Gadd, Henrik
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS). Öresundskraft, Helsingborg, Sweden.
    Werner, Sven
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS).
    A data-driven approach for discovering heat load patterns in district heating2019Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 252, artikel-id 113409Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Understanding the heat usage of customers is crucial for effective district heating operations and management. Unfortunately, existing knowledge about customers and their heat load behaviors is quite scarce. Most previous studies are limited to small-scale analyses that are not representative enough to understand the behavior of the overall network. In this work, we propose a data-driven approach that enables large-scale automatic analysis of heat load patterns in district heating networks without requiring prior knowledge. Our method clusters the customer profiles into different groups, extracts their representative patterns, and detects unusual customers whose profiles deviate significantly from the rest of their group. Using our approach, we present the first large-scale, comprehensive analysis of the heat load patterns by conducting a case study on many buildings in six different customer categories connected to two district heating networks in the south of Sweden. The 1222 buildings had a total floor space of 3.4 million square meters and used 1540 TJ heat during 2016. The results show that the proposed method has a high potential to be deployed and used in practice to analyze and understand customers’ heat-use habits. © 2019 Calikus et al. Published by Elsevier Ltd.

  • 36.
    Chaath, Alaaeddin
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Bio- och miljösystemforskning (BLESS), Energivetenskap. PRIVATE.
    Improving the Design of Wind Turbine Plants: Future Design of Wind Turbine Plants2016Självständigt arbete på avancerad nivå (masterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Applying the new ideas developed by the present study on the current design of WTP can lead to satisfactory results and give flexibility in terms of producing more electrical power during periods of low/medium wind velocity. The innovative ideas and methods included in the present work reveal the features of the future renewable energy designs that could, in the few coming years, revolutionize the field of wind turbine designs worldwide. Also, increase the capacity factor significantly, since the application of these ideas in areas where wind class II and III blows have proven to be very effective. Especially, when compares the result of new ideas with the current wind turbine designs.

    Testing the innovative ideas regarding the future wind turbines on a current WTP achieved a good results in increasing electric energy production over the year. For example applies the new ideas on a WTP model Enercon (E-101) will achieve an annual increase around 20% of electric power generation (wind class II, Cp = 36), i.e. when wind speed is ranging from 0-10 m/s (Level C – option 02) the production improved at the highest value, reaching up to +46%. Also, in Level B the generation of electricity witnessed an increase up to 10% when the wind velocity being always between level C with a minimum of 10 meters per second and Level A (Level A is the maximum output value, which is changing from one turbine type to the other). 

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  • 37.
    Chen, Kunru
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Recurrent Neural Networks for Fault Detection: An exploratory study on a dataset about air compressor failures of heavy duty trucks2018Självständigt arbete på avancerad nivå (masterexamen), 80 poäng / 120 hpStudentuppsats (Examensarbete)
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    fulltext
  • 38.
    Dahlgren, Patrik
    et al.
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Heehrle, Emil
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Persson, Jim
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Analys av Örkelljunga Utbildningscentrums IT-miljö2013Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I dagens samhälle där tillgången till information är nästintill obegränsad och nätverkfinns överallt ökar kraven på IT-säkerhet. Gratis programvaror och information omhur man använder dessa finns enkelt tillgängliga för vem som helst på Internet idag.Då många av dessa programsviter har full support och de är mycket användarvänligainnebär det också att fler kan utföra intrång och attacker mot olika IT-miljöer utanatt behöva inneha expertis inom området. Ett hjälpmedel mot dessa hot ärpenetrationstesting, där man kan identifiera eventuella brister och sårbarheter i ettgivet IT-system.Den här rapportens mål har varit att utreda om Örkelljunga Utbildningscentrums ITsäkerhetstår i proportion till känsligheten på informationen som de innehar ochbehandlar.Detta har gjorts genom ett penetrationstest, där man på plats har skannat skolansnätverk efter sårbarheter och möjliga intrångsvägar.Därefter har sårbarheterna utvärderats och rankats efter hur kritiska de anses varaoch utifrån detta teoretiskt bevisat hur man som attackerare hade kunnat gå till vägaför att komma åt eller förstöra känslig information.Resultaten visade på ett flertal kritiska brister som vid närmare analys hade kunnatutnyttjas för att ta sig in i systemet och eventuellt komma åt känslig information.Slutsats blev därför att Örkelljunga Utbildningscentrums IT-miljö för närvarande intehar tillräcklig säkerhet i proportion till känsligheten på information som de innehar.

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  • 39.
    Dalati, Fares
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Martinez Lopez, Pablo Enrique
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Vital Sign Radar Redesign: Further Development of a Compact, Highly integrated 60 GHz Radar for Human Vital Sign Monitoring2017Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Nowadays, thanks to the modern technologies, the human being has been able todevelop new techniques to solve problems present in the past. Regarding the medicalfield, it is common to use several apparatus in order to measure the vital signs. Themain drawback about the traditional methods employed for this purpose is that theyare invasive towards the patient. However, in this thesis it has been developed afurther design of a radar system so as to be able to measure these vital signs in awireless way.

    Based on a 60 GHz frequency modulated continuous wave radar chip, it has been ableto increase the performance of the measurements by adding a second radar chip.Because of this new feature, the radar system is now having a better precision byprocessing greater data matrix to analyse the targets positions and theirmeasurements. In addition, an enhanced MCU has been incorporated in order toavoid performance bottlenecks because it is necessary to handle the processing of thedata received by the two radar chips. Lastly, reducing the sweeping time (periodbetween the lowest frequency broadcast to linearly reach the highest frequencybroadcast) from 20 ms the previous design to 1 ms, which requires higher samplingrate to cover the fast sweep and provide higher flow of information that leads to fasterdetection process.

    A 3D design of the prototype has been designed to show the physical appearance itwould have once entering in production. The result is a compact and highlyintegrated radar system which will be able to monitor the heart beating andrespiration frequency of a human being in a range of ten meters.

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    fulltext
  • 40.
    D'Ambrosio, Marco
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET). Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Medaglia, Marco
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET). Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Vertical Axis Wind Turbines: History, Technology and Applications2010Självständigt arbete på avancerad nivå (masterexamen), 15 poäng / 22,5 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In  this  Master Thesis  a  review  of  different  type  of  vertical  axis  wind turbines (VAWT)  and  a preliminary investigation of a new kind of VAWT are presented.

    After an introduction about the historical background of wind power, the report deals with a more accurate analysis of the main type of VAWT, showing their characteristics and their operations. The aerodynamics of the wind turbines and a review of different type on generators that can be used to connect the wind mill to the electricity grid are reported as well.

    Several statistics are also presented, in order to explain how the importance of the wind energy has grown  up  during  the  last  decades  and  also  to  show  that  this development  of  the  market  of  wind power  creates  new  opportunity  also  for VAWT,  that  are  less  used  than  the  horizontal  axis  wind turbine (HAWT).

    In the end of 2009 a new kind of vertical axis wind turbine, a giromill 3 blades type, has been built in Falkenberg, by the Swedish company VerticalWind. The tower of this wind turbine is made by wood,  in  order  to  get  a  cheaper  and  more environment  friendly  structure,  and  a  direct  driven synchronous multipole with permanent magnents generator is located at its bottom. This 200 kW VAWT represents the intermediate step between the 12 kW prototype, built in collaboration with the Uppsala University, and the common Swedish commercial size of 2 MW, which is the goal of the company.

    A  preliminary  investigation  of  the  characteristics  of  this  VAWT  has  been done, focusing  in particular on the value of the frequency of resonance of the tower, an important value that must be never reached during the operative phase in order to avoid serious damage to all the structure, and on the power curve, used to evaluate the coefficient of power (Cp) of the turbine. The results of this investigation and  the steps  followed  to  get  them  are  reported.  Moreover  a  energy production analysis of the turbine has been done using WindPro, as well as a comparison with and older type on commercial VAWT.

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    FULLTEXT01
  • 41.
    Davidsson, Martin
    et al.
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Karlsson, Jonas
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE).
    Mätning och analys av elkvalité2012Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
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    Mätning och analys av elkvalité
  • 42.
    De Lauretis, Maria
    et al.
    Embedded Internet Systems Lab, Luleå University of Technology, Luleå, Sweden.
    Haller, Elena
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS).
    Di Murro, Francesca
    Department of Industrial and Information Engineering and Economics, University of L’Aquila, Abruzzo, Italy.
    Romano, Daniele
    Department of Industrial and Information Engineering and Economics, University of L’Aquila, Abruzzo, Italy.
    Antonini, Giulio
    Department of Industrial and Information Engineering and Economics, University of L’Aquila, Abruzzo, Italy.
    Ekman, Jonas
    Embedded Internet Systems Lab, Luleå University of Technology, Luleå, Sweden.
    Kovačević-Badstübner, Ivana
    Advanced Power Semiconductor Laboratory, ETH Zürich, Zürich, Switzerland.
    Grossner, Ulrike
    Advanced Power Semiconductor Laboratory, ETH Zürich, Zürich, Switzerland.
    On the rectangular mesh and the decomposition of a Green's-function-based quadruple integral into elementary integrals2022Ingår i: Engineering analysis with boundary elements, ISSN 0955-7997, E-ISSN 1873-197X, Vol. 134, s. 419-434Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Computational electromagnetic problems require evaluating the electric and magnetic fields of the physical object under investigation, divided into elementary cells with a mesh. The partial element equivalent circuit (PEEC) method has recently received attention from academic and industry communities because it provides a circuit representation of the electromagnetic problem. The surface formulation, known as S-PEEC, requires computing quadruple integrals for each mesh patch. Several techniques have been developed to simplify the computational complexity of quadruple integrals but limited to triangular meshes as used in well-known methods such as the Method of Moments (MoM). However, in the S-PEEC method, the mesh can be rectangular and orthogonal, and new approaches must be investigated to simplify the quadruple integrals. This work proposes a numerical approach that treats the singularity and reduces the computational complexity of one of the two quadruple integrals used in the S-PEEC method. The accuracy and computational time are tested for representative parallel and orthogonal meshes. © 2021 The Authors

  • 43.
    De Lauretis, Maria
    et al.
    Luleå University of Technology, Luleå, Sweden.
    Haller, Elena
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Romano, Daniele
    University of L'Aquila, L'Aquila, Italy.
    Antonini, Giulio
    University of L'Aquila, L'Aquila, Italy.
    Ekman, Jonas
    Luleå University of Technology, Luleå, Sweden.
    Kovačević-Badstübner, Ivana
    ETH Zürich, Zürich, Switzerland.
    Grossner, Ulrike
    ETH Zürich, Zürich, Switzerland.
    On the Decoupling of Integrals in the Surface PEEC Method2022Ingår i: 2022 International Symposium on Electromagnetic Compatibility – EMC Europe, Danvers: IEEE, 2022, s. 355-360Konferensbidrag (Refereegranskat)
    Abstract [en]

    Electromagnetic problems can be solved by using the integral form of Maxwell equations. The Surface Partial Element Equivalent Circuit (S-PEEC) method is an integral equation-based method that is suitable when high-frequency effects, such as skin and proximity effect, are dominant. However, the computation of interaction quadruple integrals is computationally expensive and numerically unstable due to singularities. In previous work, we proved how to decouple one of the quadruple integrals, and showed the gaining in stability and computational time. In this work, we extend the result to the second integral with the curl of the Green's function. Numerical examples prove the acceleration in terms of computational time achieved with the proposed approach. Future work will focus on integration strategy and further optimization of the proposed algorithm. © 2022 IEEE.

  • 44.
    Druyts, Jan
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Bio- och miljösystemforskning (BLESS), Energiteknik.
    Control induction motor by frequency converter: Simulation electric vehicle2010Självständigt arbete på avancerad nivå (magisterexamen), 15 poäng / 22,5 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Summary

     Today we are probably on a point of change for the car industry. The last century was the century of vehicles with internal combustion engines. Fossil fuels were relative cheap, easy accessible and they have a high specific energy. The pollution and dependency on oil caused the last decade an increasing demand for alternatives. Alternatives for electric power plants and for car drives. Yet the turnover to hybrids is a fact and much research is done for pure electric vehicles. Research about the control of electric motors is by that become a hot topic.

    To simulate an electric vehicle drive with an induction motor, a frequency converter is needed. This combination of motor and converter led to many possible experiments. With a few experiments already done and a broad theoretical background report this thesis provides a good bundle of information to start with further experiments. The experiments can become even broader when a flywheel is added as mass inertia momentum and a DC source on the DC-link. Both elements contribute for a better simulation of an electric motor in an electric vehicle.

    What is described in this theoretical report about the combination of an induction motor and converter is only the tip of the iceberg. I had too less time to begin experimenting with the flying wheel. The DC-link voltage becomes ca. 540V. From the perspective of safety I could never work alone with the DC-link. Even with a companion it was too dangerous because the equipment of the Halmstad University is not made for such dangerous voltages. That’s why this thesis contains more theoretical background and less actual practical data.

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    FULLTEXT01
  • 45.
    Ebers, Lucas
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Eriksson, Niklas
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Projektering av lokalnät med fördjupning i selektivitet2019Självständigt arbete på grundnivå (högskoleexamen), 180 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Inom elkraftsystem, när ett luftburet lokalnät ersätts med ett markförlagt förändras förutsättningarna i formav materialets egenskaper och det ger möjlighet för uppdaterad dimensionering. Målet var att presentera ettförslag på ombyggnation av ett äldre luftburet till ett modernare markförlagt lokalnät och presenteraselektivplaner för samtliga grenar av det nya nätet. Metoder som använts är Velanders metod försammanlagring av maxeffekter, dimensionering enligt Svensk Standard och kurvanpassning avutlösningskurvor för att presentera digitalt framställda selektivplaner. Det markförlagda lokalnätet levereraren bättre elkvalitet, uppfyller utlösningsvillkoret och erhåller god selektivitet.

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  • 46.
    Ehrinton, Jakob
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Vähäkangas, Elias
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Update of electrical installation in Volvo FM/FMX Crew Cab2023Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In today's society, technology that does not have integrated app control or digital control is considered outdated. In fact, the technological growth of new features and innovations has grown exponentially over the past 100 years. This rapid development makes it difficult for manufacturers of larger products and machinery to keep up, both due to time constraints and economic reasons.

    The purpose of the thesis was to evaluate the benefits of digitalizing the electrical system in a vehicle, as well as developing a demorig with accompanying electrical architecture that demonstrates its feasibility. During the course of the work, it became clear that the major benefits of digitalizationwere a reduction in errors and malfunctions, while increasing flexibility and communication capabilities.

    Finally, a fully functional solution was presented that was tailored to meet the requirements of Volvo Trucks, with the goal of being implemented in the next version of their Crew Cab. The logic behind the system was functionally tested in a demo rig that included all components from the cab. The project demonstrated a significant reduction in cabling with the ability to control components with high precision through pulse width modulation signals and transistors.

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  • 47.
    Eklund, Petter
    et al.
    Högskolan i Halmstad, Akademin för företagande, innovation och hållbarhet, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS). Uppsala University, Uppsala, Sweden.
    Sjolund, Jonathan
    Uppsala University, Uppsala, Sweden.
    Berg, Marcus
    Uppsala University, Uppsala, Sweden.
    Leijon, Mats
    Uppsala University, Uppsala, Sweden; Chalmers University of Technology, Gothenburg, Sweden.
    Eriksson, Sandra
    Uppsala University, Uppsala, Sweden.
    Experimental Evaluation of a Rare Earth-Free Permanent Magnet Generator2021Ingår i: IEEE transactions on energy conversion, ISSN 0885-8969, E-ISSN 1558-0059, Vol. 36, nr 1, s. 3-10Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Low speed, high torque machines are used in wind turbines where the turbine rotor is directly connected to the generator. A permanent magnet synchronous generator using high-energy rare-earth permanent magnets (PMs) is one common choice for this application, but rare-earth PMs have supply insecurities and cost risks. A rare-earth free 32-pole PM generator, using ferrite PMs in a spoke-type rotor, for use in a 12 kW experimental wind turbine is built and tested. Voltages and currents at load and no load are measured, as well as the magnetic field in the end regions of the machine. The generator can deliver the required power at nominal speed and has low harmonic content in the output. The electrical measurements are compared to two-dimensional finite element design calculations and the experimental results are lower than expected from simulations. The measured voltage is lower than expected, requiring a higher current than calculated for the rated power. Three-dimensional magnetic field simulations show that there are leakage flux paths in the end-regions that the two-dimensional design calculations overlook, explaining the discrepancy between simulations and measurements. © 1986-2012 IEEE.

  • 48.
    Emanuelsson, Petter
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Metodframtagning för hastighetsberoende tester på stillastående bil2017Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
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    fulltext
  • 49.
    Eriksson, Hannes
    et al.
    Högskolan i Halmstad.
    Brange Sollie, Ivan
    Högskolan i Halmstad.
    Wireless IO: A wireless accessory for integration of an Axis Communications camera in a sensor network.2017Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    When installing new network security cameras in buildings, the cameras are often connected to sensors via signal wires. Since most building already have internet and electricity drawn throughout the structure, the procedure of routing a new signal wire can be costly and time demanding. By replacing this wire with a wireless link, the cost and time it takes for the customer to install a camera could be reduced.

    The objective for this thesis is to investigate different wireless technologies used in short range, low power wireless communication networks such as PANs and LANs. Focusing on technologies used in the surveillance segment a decision will be made on which wireless technology that would suit as a link between a sensor and a camera for transmitting trigger signals. The technology will then be implemented in a proof-of-concept accessory, which can give an Axis Communications camera wireless functionality through it’s IO port.

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    fulltext
  • 50.
    Eriksson, Sandra
    et al.
    Uppsala University, Uppsala, Sweden.
    Eklund, Petter
    Högskolan i Halmstad, Akademin för företagande, innovation och hållbarhet, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS).
    Effect of magnetic properties on performance of electrical machines with ferrite magnets2021Ingår i: Journal of Physics D: Applied Physics, ISSN 0022-3727, E-ISSN 1361-6463, Vol. 54, nr 5, artikel-id 054001Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The increased focus on ferrite magnets makes it interesting to investigate their suitability in electrical machines such as generators for wind power and motors for electric cars. Efforts are currently being made to improve the magnetic properties of ferrites. A simulation method is used to investigate how different magnetic properties such as remanence, coercivity and intrinsic coercivity affect the performance of electrical machines, here quantified as output torque. It is also ensured that the magnet is not partly demagnetized during a short-circuit event. Simulations are performed through a two-dimensional finite-element-based simulation method. Not all combinations of magnetic properties will render a usable design and it is therefore investigated how high the required values are for different magnetic properties as well as how high an output torque can be achieved. It is concluded that increasing the remanence or the coercivity can be quantified as an improved energy product, whereas improvement of the intrinsic coercivity enables the magnet to have a more optimal shape and thereby have a working point where the energy product is maximized. In addition it is found that for a fixed available magnetic energy, the performance does not change significantly with increasing remanence © 2020 IOP Publishing Ltd.

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