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  • 1.
    Adelakun, Olawale
    University West, Department of Economics and IT.
    The Role of Business Intelligence in Government: A Case Study of a Swedish Municipality Contact Center2012Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    The aim of this study is to investigate the role Business Intelligence (BI) can play in government and more specifically at the municipality level. The study aims to investigate how data collected from a municipality Contact Center can be leveraged with the help of a BI solution. The study focuses on the Contact Center at Järfälla Kommun (municipality) and investigates whether a BI implementation can help to realize more effective planning, resource allocation and improved services and e-services. Municipality Contact Centers are becoming an increasingly popular precedent providing municipal residents with a centralized service where they can make inquiries, provide information, lodge complaints or commend actions related to activities within the specific municipality. BI can turn raw data into concrete figures and reports, map patterns and trends and support effective decision making. It can also however be costly and difficult to integrate and face resistance due to perceived complexity. This paper aims to take such notions into consideration and investigate the feasibility of implementing such a solution in the context of a municipality Contact Center.

    This paper identifies various benefits and drawbacks from literature which are then modeled into a SWOT framework. In addition, semi-structured interviews are utilized in this study and targeted at stakeholders knowledgeable in the Contact Center, BI, or both. Findings from the SWOT framework will be measured against the findings from the interviews and an analysis of correlations between the two sources will be investigated.

  • 2.
    Alizadeh-Khameneh, Mohammad Amin
    et al.
    Division of Geodesy and Satellite Positioning, Royal Institute of Technology (KTH), Stockholm, Sweden.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Sjöberg, Lars
    Division of Geodesy and Satellite Positioning, Royal Institute of Technology (KTH), Stockholm, Sweden.
    The Effect of Instrumental Precision on Optimisation of Displacement Monitoring Networks2016In: Acta Geodaetica et Geophysica Hungarica, ISSN 1217-8977, E-ISSN 1587-1037, Vol. 51, no 4, p. 761-772Article in journal (Refereed)
    Abstract [en]

    In order to detect the geo-hazards, different deformation monitoring networks are usually established. It is of importance to design an optimal monitoring network to fulfil the requested precision and reliability of the network. Generally, the same observation plan is considered during different time intervals (epochs of observation). Here, we investigate the case that instrumental improvements in sense of precision are used in two successive epochs. As a case study, we perform the optimisation procedure on a GPS monitoring network around the Lilla Edet village in the southwest of Sweden. The network was designed for studying possible displacements caused by landslides. The numerical results show that the optimisation procedure yields an observation plan with significantly fewer baselines in the latter epoch, which leads to saving time and cost in the project. The precision improvement in the second epoch is tested in several steps for the Lilla Edet network. For instance, assuming two times better observation precision in the second epoch decreases the number of baselines from 215 in the first epoch to 143 in the second one.

  • 3.
    Arkevall, Martin
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Lundgren, Simon
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Återställning av filer: jämförelse av tre gratisverktyg2017Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    To try find a lost file which has been deleted by mistake is probably a common issue for many users. The fact that the recycle bin has been erased too makes the situation more complicated. Or even worse, if a whole partition was reformatted and overwritten. Most users are aware of available support either by contacting a data recovery company or by searching the internet for free tools. Because of the above mentioned common issues, the project has selected three recovery tools to test and compare to find out which tool performs best regarding recovery out of a selection of lost common files. The selection of tools were based from a list with mandatory requirements. The three tools that passed the list was Recuva, Lazesoft and Puran. The results showed variances between the tools where one tool was best in test to recover files back to its original. Another tool performed best when the original size increased after file recovery but the actual data still was functioning properly.

  • 4.
    Bengtsson, Simon
    et al.
    University West, School of Business, Economics and IT, Division of Media and Design.
    Nyholm, Carl
    University West, School of Business, Economics and IT, Division of Media and Design.
    Kortfilm - födkrok eller språngbräda?: En undersökning om de digitala plattformarnas påverkan på distributionen av svensk kortfilm2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The intent of this paper is to examine the conditions for Swedish filmmakers with the short film format as final goal. Through a qualitative study we investigate what paths there are for distributing short films through the digital platforms available today. We do this by interviewing some of the most experienced and successful short film creators in Sweden and one of Sweden's main financier in film creation, to provide as just image of the branch as we can.

    Short films with financing from the state and regional financiers rarely has any focus on economic gain. They are rather intended to help form filmmakers and give them an opportunity to establish themselves prior to further filmmaking.

    The main digital platform in Sweden is SVT Play, witch is much based on the fact that SVT is part of sponsoring a big part of the government financed short films. The greatest problem we found is the availability for short films through digital platforms, since SVT Play most often has exclusive rights and only buy viewing rights during periods.

    When you want to distribute your short film, the most important aspect is the context, the film should not only appeal the audience it reaches but it also has to appeal the audience in the situation where it reaches them.

  • 5.
    Bernhard, Irene
    University West, Department of Economics and IT, Division of Media and Design.
    Incentives for Inclusive e-Government: The Implementation of Contact Centers in Swedish Municipalities2015In: Digital Solutions for Contemporary Democracy and Government / [ed] Bwalya, Kelvin Joseph & Mutula, Stephen, IGI Global, 2015, 1, p. 304-327Chapter in book (Refereed)
  • 6.
    Brahm, Fredrik
    et al.
    University West, Department of Engineering Science.
    Kristiansson, Lennart
    University West, Department of Engineering Science.
    Wennerström, Joakim
    University West, Department of Engineering Science.
    Energimätning vid Högskolan Väst2011Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Svenskarna är med en elförbrukning av cirka 15000 kWh per person de fjärde största elför-brukarna i världen. Det beror främst på det kalla klimatet, men även stora industrier med hög elförbrukning bidrar till konsumtionen. Högskolan Väst förbrukar årligen 3 miljoner kWh. Med stigande elpriser och ett ökat fokus på miljöpåverkan önskar skolan att sänka sin förbrukning.

    Examensarbetet har utförts på uppdrag av kWh kontroll och NEA gruppen. Mätningar har utförts på matande ledning till skolans alla huskroppar samt dess ventilation. Syftet med examensarbetet var att lokalisera energiförbrukare inom Högskolan Väst och ge förslag för att minska förbrukningen med fokusering på minskad belysning nattetid och helger. För att mäta elförbrukningen användes elkvalitetsanalysatorer och enklare energimätare.

    kWh kontroll har som mål att sänka elförbrukningen med 6 % vilket motsvarar 180000 kWh per år. Under Earth Hour sänktes förbrukningen med 40 kW i huskropparna E-J och 10 kW i huskropparna B-D. Baserat på dessa resultat skulle det genom att släcka ner natte-tid, då skolan är larmad, innebära en årlig besparing på 115000 kWh.

    Energimätningar har även gjorts på datorer och resultatet visade att om strömmen till sko-lans datorer kan brytas under larmad tid skulle detta ge en besparing på cirka 8200 kWh om året.

    Rapporten visar att Högskolan Västs elförbrukning under nattetid går att reduceras enligt de olika förslag som beskrivs.

  • 7.
    Broberg, Patrik
    University West, Department of Engineering Science, Division of Process and Product Development.
    Evaluation of a method to radiometric calibrate hot target image data by using simple reference sources close to ambient temperatures2010In: Infrared Imaging Systems: Design, Analysis, Modeling, and Testing XXI / [ed] Gerald C. Holst, Keith A. Krapels, 2010Conference paper (Other academic)
    Abstract [en]

    To perform radiometric calibrations of image data, reference sources are needed in order to acquire data at two or more radiance levels giving the calibration parameters. Due to sensor drift for detectors in the infrared region the parameters have to be frequently recalculated during an extended signature measurement if the accuracy is to be maintained. In signature measurements where the incident radiance levels from hot targets are exceeding the background by many orders of magnitude the reference sources need to emit radiation at high radiance levels. Such reference sources are more complex and so is the handling of these sources. The calibration procedure tends to become impractical in field trials where several spectral bands are involved, which increases the need for reference data and the number of reference sources. A method to radiometric calibrate hotspot target data by using only a few simple reference sources close to ambient temperatures has been evaluated in this paper. Reference data has been collected both in laboratory studies and in field trials at various weather conditions. The accuracy and the precision of the method are presented. The uncertainty due to sensor drift is estimated. Error sources connected to the calibration method are discussed.

  • 8.
    Bäckman, Kjell
    University West, Department of Economics and IT, Divison of Informatics.
    Automatic fitness in generative jazz soloimprovisation2012In: EIMAS 2012 Conference Proceedings, Juiz de Fora, Brazil, 2012, p. 1-10Conference paper (Refereed)
    Abstract [en]

    Recent work by the author has revealed the need for an automatic fitness function in the evolutionary algorithm

    for generation of jazz solos. A computer based automatic fitness function enables greater populations and a great

    number of generations within a manageable time. This paper describes how the automatic fitness function is

    implemented using score calculation based on specific events recognized in the solo line The evaluation function

    is based on the author’s solo analysis of 73 great masters’ solo characteristics and their techniques used for buildup

    of jazz solos.

  • 9.
    Choquet, Isabelle
    University West, Department of Informatics and Mathematics.
    Nozzle exit geometry and lump formation in atmospheric plasma spraying2005In: International Thermal Spray Conference: Basel, Switzerland, May, ASM International , 2005, p. 259-264Conference paper (Other academic)
    Abstract [en]

    Plasma spraying operations performed with high carrier gas flow rate may improve the coating properties but they can also lead to lump formation and thus coating defects. The damaged work piece must then be stripped and re-coated, which implies a considerable waste in terms of coating powder, energy and time. The aim of this study was to determine the cause of the lumps, and propose process modifications for avoiding their formation while keeping the coating quality. Numerical simulations based on 3D turbulent Navier-Stokes equations in local thermal and chemical equilibrium were carried out to understand the problem and estimate the feasibility of the proposed solutions. The computational results were supplemented by experiments for validation. A first set of investigations was focused on the location and orientation of the powder port injector. It turned out that it was not possible to keep the coating quality while avoiding lump formation by simply moving the powder injector. A new geometry of the nozzle exit was then designed and successfully tested for a first application with Ni-5Al powder used in production. 

  • 10.
    Choquet, Isabelle
    et al.
    University West, Department of Engineering Science.
    Lucquin-Desreux, Brigitte
    University Pierre and Marie Curie, Paris, France.
    Non equilibrium ionization in magnetized two-temperature thermal plasma2011In: Kinetic and Related Models, ISSN 1937-5093, E-ISSN 1937-5077, ISSN 1, Vol. 4, no 3, p. 669-700Article in journal (Refereed)
    Abstract [en]

    A thermal plasma is studied accounting for both impact ionization, and an electromagnetic field. This plasma problem is modeled based on a system of Boltzmann type transport equations. Electron-neutral collisions are assumed to be much more frequently elastic than inelastic, to complete previous investigations of thermal plasma . A viscous hydrodynamic/diffusion limit is derived in two stagesdoing an Hilbert expansion and using the  Chapman-Enskog method. The resultant viscous fluid model is characterized by two temperatures, and non equilibrium ionization. Its diffusion coefficients depend on the magnetic field, and can be computed explicitely.

  • 11.
    Choquet, Isabelle
    et al.
    University West, Department of Technology, Mathematics and Computer Science.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Wigren, J
    Deposition Rate Increase in APS Processes by Means of Multiple Injection Ports2004In: Thermal Spray 2004: Advances in Technology and Application: Proceedings of the International Thermal Spray Conference 10–12 May 2004, Osaka, Japan, 2004, p. 691-695Conference paper (Other academic)
  • 12.
    Curry, Nicholas
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Markocsan, Nicolaie
    University West, Department of Engineering Science, Division of Production Engineering.
    Li, Xin-Hai
    Tricoire, Aurelien
    Dorfman, Mitchell
    Next Generation Thermal Barrier Coatings for the Gas Turbine Industry2010In: Proceedings of the Thermal Spray: Global Solutions for Future Application (ITSC 2010) Conference: Singapore, May 3-5, 2010, 2010, p. 716-722Conference paper (Refereed)
  • 13.
    Dahlmo, K I
    et al.
    Nobel Biocare, Göteborg.
    Andersson, M
    Gellerstedt, M
    University West, Department of Economics and IT.
    Karlsson, S
    On a new method to assess the accuracy of a CAD program.2001In: International Journal of Prosthodontics, ISSN 0893-2174, E-ISSN 1139-9791, Vol. 14, no 3, p. 276-83Article in journal (Refereed)
    Abstract [en]

    PURPOSE: This study was initiated with the purpose of developing and evaluating a system for measuring the magnitude of the variation between a computer-aided design (CAD) object created on the computer screen and a replicated object produced by computer-aided manufacturing (CAM). MATERIALS AND METHODS: Controlled geometric forms, a square and a cone, were designed in a CAD program, and measuring distances were selected. The CAD data were transmitted to CAM data, and objects were produced. The CAD/CAM process was the Procera system, and the holder system permitted the objects to be ground into cross sections, similar to the visualization in the CAD program. Five objects of each shape were produced and measured by two operators two times. Three operators measured one of the objects 30 times. RESULTS: Observed values were greater than the true value. For all objects, the systematic error was at most 15.5 microns. Interoperator difference was small. The variation because of measurement error was greater for the square object compared to the cone. However, the variation because of object was higher for the cone object than for the square. The total standard deviation was 7.7 microns. Thus, the total random error caused by object variation and measurement error was in approximately 95% of all measurements less than 15 microns. CONCLUSION: There are no differences in the measurement data derived from this method and actual measurement data from an object created by the computer-aided dental design program. The method has high validity and reliability, i.e., high accuracy.

  • 14.
    Damfelt, Christoffer
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Nilsson, Simon
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Prestandautvärdering av enkortsdatorn BPI-R1 jämfört med traditionella hemroutrar2017Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    In modern times IT gets a major role in people lives. More devices get connected and most familymembers have several connected devices which results in a rising utilization of the home network. Due to this we conducted this project with the intent of evaluating the single-board computer BPI-R1 to traditional home routers in order to establish whether it is applicable for common use as a home router.

    The devices was evaluated by measuring the throughput with iperf in several different scenarios. Throughput is the maximum achievable bandwidth after the traffic has been affected by various factors such as overhead.

    The devices that the BPI-R1 was compared to was a TP-link TL-WR1043WND and a Netgear WNR3500L. Iperf3 was used both to generate the traffic and to gather the results of the measurements. The tests was conducted in three steps. Basic tests on a port-to-port basis and two scenario tests. The basic tests was LAN-LAN, LAN-WAN and WIFI-LAN while scenario one was all the basic tests conducted simultaneously. Scenario two was a WAN-max test where four separate data streams were sent from different LAN-ports to the WAN-port. Iperf3 were being run on Dell Latitude E4130 for cabled traffic and a Samsung Galaxy S7 edge were used for the Wireless traffic.

    The results for the basic tests show that LAN-LAN gave similar results on all devices, on LAN-WAN the results differed vastly between the devices. On WIFI-LAN it differed but not as vastly as in LAN-WAN, and the traffic showed typical behavior of wireless transfers. Both in scenario test one and two it displayed major differences in performance between the devices as well as a major difference between scenario tests and basic tests.

  • 15.
    Danielsson, Fredrik
    et al.
    University West, Department of Technology.
    Ericsson, Mikael
    University West, Department of Technology.
    Computer Aided Robotics combined with a Finite Element Analysis for Process Simulation of Welding2004In: 35th International Symposium on Robotics, ISR 2004: Paris, mars 2004, Paris: International Federation of Robotics , 2004Conference paper (Refereed)
  • 16.
    Danielsson, Fredrik
    et al.
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Gustavsson Christiernin, Linn
    University West, Department of Engineering Science.
    An Adaptable Process Planning Tool: A Tool for Information, Communication, and Interaction in a Robot Cell2011In: ADAPTIVE 2011: the Third International Conference on Adaptive and Self-Adaptive Systems and Applications / [ed] Fox, Jorge & Rausch, Andreas, International Academy, Research and Industry Association (IARIA), 2011, p. 15-19Conference paper (Refereed)
    Abstract [en]

    This study presents work in progress on how to develop a process-planning tool to handle interaction between human operators and robots within a robot cell. First, we introduce how to include human activities in the process flow; then, we turn to our ideas for communication and feedback systems inside a robot cell. A small example of how to design interactive and re-programmable screens is presented.

  • 17.
    Edstorp, Marcus
    et al.
    University West, Department of Technology, Mathematics and Computer Science.
    Eriksson, Kenneth
    University West, Department of Technology, Mathematics and Computer Science.
    Modelling and Simulation of Moving Boundaries and Convective Heat Transfer in Non-Autogenous Fusion Weld Pools using FEMLAB 3.12005In: Proceedings of the FEMLAB CONFERENCE 2005, 2005, p. 85-90Conference paper (Other academic)
  • 18.
    Emanuelsson, Andreas
    et al.
    University West, Department of Engineering Science.
    Paavilainen, Roger
    University West, Department of Engineering Science.
    Inventering och riskanalys av skolskjutshållplatser: kvalitetsäkring med avseende på trafiksäkerhet2010Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In Trollhättan municipality approximately 700 school bus stops are in service. To ensure high quality of the performance of school bus operations, with focus on traffic safety, it was decided to conduct a survey of bus stops including assessments of risks.

    This master thesis aims to identify the factors affecting road safety at bus stops and pedestrian connections, and to conduct an inventory and analysis of selected sites in Trollhättan municipality. The work also aims to show examples of how risk assessment should be performed in future studies. A risk analysis model provided by the Swedish Transport Administration is supplemented and used in a field study. The risk assessment is based on, inter alia, traffic flow, visibility distance, lighting, speed of traffic and the presence of bus shelter. A total number of 93 bus stops and 228 pedestrian connections are examined during the field study. The result shows that the connections are generally a larger traffic safety problem than the bus stops.

    The risk analysis model uses both objective and subjective assessments. Applying subjective assessments to supplement objective is beneficial, but there are some difficulties in making subjective judgments. Those require that the evaluator possess much knowledge and experience in traffic safety and it is difficult to always be consistent when setting subjective ratings.

    The group recommends the city of Trollhättan to proceed with field testing of bus stops and pedestrian connections, and to regularly conduct surveys of passenger’s experiences and views on safety. Furthermore it is recommended that the bus drivers carry out a risk analysis from their perspective.

  • 19.
    Ericsson, Mikael
    University West, Department of Technology, Mathematics and Computer Science.
    Simulation fo Robot Paths and Heat Effects in Welding2006Doctoral thesis, comprehensive summary (Other academic)
  • 20.
    Ericsson, Mikael
    University West, Department of Technology.
    Simulation of robotic TIG-welding2003Licentiate thesis, comprehensive summary (Other academic)
  • 21.
    Ericsson, Mikael
    et al.
    University West, Department of Technology, Mathematics and Computer Science. University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Berglund, D.
    Nylén, Per
    University West, Department of Technology, Mathematics and Computer Science. University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Three Dimensional Simulation of Robot path, Heat Transfer and Residual Stresses of a TIG-welded Part with Complex Geometry2002In: Trends in Welding Research: Proceedings of the 6th International Conference: Phoenix, AZ, 15-19 April, 2002, 2002, p. 973-978Conference paper (Other academic)
    Abstract [en]

    In this paper a system is presented that combines a robot off-line programming software with a finite element model that predicts temperature-time histories and residual stress distributions. The objective is to develop a tool for the engineer where robot trajectories and welding process parameters can be optimized on parts with complex geometry. The system was evaluated on a stainless steel gas turbine component. Robot weld paths were defined off-line and automatically downloaded to the finite element program, where transient temperatures and residual stresses were predicted. Temperature dependent properties and phase change, were included in the analysis. Assumptions and principles behind the modeling techniques are presented together with predicted temperature histories, residual stresses, and fixture forces.

  • 22.
    Ericsson, Mikael
    et al.
    University West, Department of Technology, Mathematics and Computer Science.
    Henriksson, P.
    Non-contact Temperature Measurements using an Infrared Camera in Aerospace Welding Applications2002In: 6th International Conference on Trends in Welding Research: Phoenix, AZ; 15-19 April 2002, Materials Park: ASM International , 2002, p. 930-935Conference paper (Refereed)
    Abstract [en]

    This paper describes the application of infrared (IR) thermal imaging and temperature measurements in welding applications, both on single plane plates and on an aero engine turbine component with complex geometry. Temperature profiles were measured on the plates using thermocouples (T/C) in combination with an IR camera system, and the results were compared. The IR camera was used both in line scan mode (270 Hz scan frequency) and in full frame mode (1 Hz frame rate). Different methods of surface treatments have been tested to handle the problem of the surface emissivity variations due to oxidation during welding. Results from measurements using thermocouples and IR camera is presented in the paper as well as temperature measurements using the IR camera on an turbine exhaust case (TEC) engine component.

  • 23.
    Ericsson, Mikael
    et al.
    University West, Department of Technology, Mathematics and Computer Science.
    Nylén, Per
    University West, Department of Technology, Mathematics and Computer Science.
    Berglund, D.
    Ling-Peng, R.
    Three dimensional simulation of robot path, heat transfer and residual stresses of a welded part with complex geometry2005In: International jourrnal for the joining of materials, ISSN 0905-6866, Vol. 17, no 2, p. 42-51Article in journal (Refereed)
    Abstract [en]

    In this article a simulation system is presented that combines computer aided robotics software used to define the welding operation, with a finite element model that predicts temperature-time histories and residual stress distributions for welding applications. The objective is to develop a tool for engineering processes in which robot trajectories and welding process parameters can be optimized off-line on parts with complex geometries. The system was evaluated on a stainless steel gas turbine component. Temperature dependent properties and phase change were included in the analysis. The turbine component was welded using an in-house TIG welding cell. The assumptions and principles that underpin the modeling techniques are presented together with predicted temperature histories, residual stresses, and fixture forces. Predicted residual stresses were compared with neutron diffraction measurements.

  • 24.
    Ericsson, Mikael
    et al.
    University West, Department of Engineering Science, Division of Automation Systems.
    Ryberg, Anders
    Nilsson, Jim
    Christiansson, Anna-Karin
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Lennartson, Bengt
    Chalmers.
    Off-Line Simulation of Advanced Stereo Vision Welding Applications2010In: Machine Vision and Applications, ISSN 0932-8092, E-ISSN 1432-1769Article in journal (Refereed)
  • 25.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering. Division of Geodesy, Royal Institute of Technology, Stockholm, Sweden.
    Lars E., Sjöberg
    Division of Geodesy, Royal Institute of Technology, Stockholm, Sweden.
    Ramin, Kiamehr
    Department of Geodesy and Geomatics, Zanjan University, Zanjan, Iran.
    Evaluation of robust techniques in suppressing the impact of outliers in a deformation monitoring network – A case study on the Tehran Milad tower network2007In: Acta Geodaetica et Geophysica Hungarica, ISSN 1217-8977, E-ISSN 1587-1037, Vol. 42, no 4, p. 449-463Article in journal (Refereed)
    Abstract [en]

    The problem of handling outliers in a deformation monitoring network is of special importance, because the existence of outliers may lead to false deformation parameters. One of the approaches to detect the outliers is to use robust estimators. In this case the network points are computed by such a robust method, implying that the adjustment result is resisting systematic observation errors, and, in particular, it is insensitive to gross errors and even blunders. Since there are different approaches to robust estimation, the resulting estimated networks may differ. In this article, different robust estimation methods, such as the M-estimation of Huber, the “Danish”, and the L 1-norm estimation methods, are reviewed and compared with the standard least squares method to view their potentials to detect outliers in the Tehran Milad tower deformation network. The numerical studies show that the L 1-norm is able to detect and down-weight the outliers best, so it is selected as the favourable approach, but there is a lack of uniqueness. For comparison, Baarda’s method “data snooping” can achieve similar results when the outlier magnitude of an outlier is large enough to be detected; but robust methods are faster than the sequential data snooping process.

  • 26.
    Fasth, Angelica
    et al.
    University West, Department of Engineering Science.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Markocsan, Nicolaie
    University West, Department of Engineering Science.
    Musalek, Radek
    Characterization of thermo-mechanical properties for thermal sprayed NiCoCrAlY coatings2010In: Proceedings of the Thermal Spray: Global Solutions for Future Application (ITSC 2010) Conference: Singapore, May 3-5, 2010, 2010, p. 431-435Conference paper (Refereed)
  • 27.
    Franzén, Mathias
    University West, Department of Engineering Science.
    Skapa ett framgångsrikt förbättringsarbete på AKzo Nobel Surface Chemistry i Stenungsund2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Dagens omgivning är full av osäkerhet, marknadssvängningar, geografiska förändringar i arbetskraft och den högteknologiska utvecklingen vilket utsätter nutidens organisationer för ständiga förändringar (Savery och Luks 2000). Detta innebär att företag på 2000-talet, genom att systematiskt förbättra verksamheten, oavbrutet måste hålla ner kvalitetsbristkostnader, minimera förluster och öka produktiviteten för att kunna bevara sin position på marknaden (Baghel, Bhuiyan och Wilson, 2005).

    I denna studie var syftet att skapa ett nytt arbetssätt och struktur för ett framgångsrikt förbättringsarbete på Akzo Nobel Surface Chemistry Stenungsund. Studien bestod dels av ett teoriavsnitt med en litteraturstudie utifrån nutida forskning och även en kvalitativ undersökning genom djupgående intervjuer med 19 medarbetare från olika ansvarsnivåer och via en enkätundersökning som gick ut till resterande medarbetare.

    Akzo Nobel Surface Chemistry är en del av Akzo Nobel koncernen som är en av världens ledande färgtillverkare. Koncernen har över 55 000 anställda i över 80 länder där ungefär 3600 anställda arbetar på ett 20-tal platser runt om i Sverige. Företaget bedriver förbättringsarbete genom daglig uppföljning ute i fabrikerna och på respektive avdelning. Dessutom samlas alla förbättringsförslag upp i en databas och en utvald styrgrupp analyserar och prioriterar dessa. Problemet är dock att det saknas struktur och systematik för hur förbättringsförslag och actionpunkter ska gå från idéer, till att genomföras och följas upp för att kunna driva igenom förbättringar.

    I detta projekt togs det fram en modell för hur företaget kan skapa förutsättningar för ettframgångsrikt förbättringsarbete genom att skapa en kreativ miljö för medarbetarna att arbeta i. Vidare poängterades vikten av att ledningen fokuserar på att generera kvalitet hos medarbetarna genom att fokusera på kärnvärden och emotionell kompetens. Därefter presenterades framtagen struktur med arbetssätt för att minimera ledtiden från förslag till genomförande och återkoppla detta genom givna forum och system. Vidare föreslogs att ledningen ska förbereda organisationen på att ett nytt förbättringsarbete är på väg och förklara varför detta är väsentligt för företagets framtida överlevnad. Detta kan skapa förutsättningar för att implementera förbättringsarbetet på ett framgångsrikt sätt med en positiv effekt på medarbetarna.

  • 28.
    Gustavsson Christiernin, Linn
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Flexibla robotceller inom fordonsindustrin: Men hur ska informationsutbytet och interaktionen ske?2012In: Fordonskomponenten, ISSN 2000-7299, no 4, p. 26-28Article in journal (Other (popular science, discussion, etc.))
    Abstract [sv]

    En stor del av bilproduktionsprocessen är automatiserad. Ett fordons alla delar passerar flera olika stationer eller celler för att justeras och installeras, och robotar och människor har olika,vanligtvis separerade, uppgifter. Ett problem med denna typ av automatiserade produktion är den tid som det tar att vidta ändringar och frånvaron av medel hos den mänskliga operatören att kommunicera och interagera med roboten på ett flexibelt vis.

  • 29.
    Gustavsson Christiernin, Linn
    et al.
    University West, Department of Engineering Science, Division of Production System.
    Hartler, Johan
    Department of Shipping and Marine Technology Chalmers Technical University Gothenburg, Sweden.
    Multi-Layered Design and Game-Based Learning as a Pedagogical Concept: How to develop proper behavior in ARPA simulator training2016Conference paper (Refereed)
    Abstract [en]

    To become a professional master mariner one has to develop many different skills and have an understanding of how to act in different situations on the bridge. Within the master mariner program at Chalmers University of Technology, Sweden, simulation technologies are used to evolve pertinent skills within the educational program. A challenge with using a full scale simulator from the outset of the program is to get the students to develop both professional competencies and internalize tacit knowledge in the navigation of a ship when the interface of the simulator itself is quite demanding. By using an adaptive Multi-Layered Design approach in combination with game based learning, this paper proposes how to guide the student through a more summative learning process. The main idea is to grant limited access to what the students can do with some functions, and gradually turn on more functionality in order to develop certain experienced behaviors to get them to understand the logical approach behind selections and to make them think through why and when they should do things.

  • 30.
    Hagqvist, Petter
    et al.
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Sikström, Fredrik
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Christiansson, Anna-Karin
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Emissivity estimation for high temperature radiation pyrometry on Ti–6Al–4V2013In: Measurement, ISSN 0263-2241, E-ISSN 1873-412X, Vol. 46, no 2, p. 871-880Article in journal (Refereed)
    Abstract [en]

    The paper demonstrates a versatile procedure suitable for industrial implementation of temperature measurement on a hot titanium alloy. The driving force has been the need for an accurate temperature measurement during additive manufacturing using laser welding technology where Ti–6Al–4V-wire is melted. The challenges consider both industrial constraints and the varying emissivity of the surface. Measurements makes use of a narrow bandwidth spot radiation pyrometer and a calibration procedure for estimation of the surface temperature through spectral emissivity estimation. The theoretical results are validated through experiments. A number of difficulties in radiation temperature measurements for metals with varying surface properties are discussed; especially the case of surface oxidation. The uncertainty in temperature reading due to the uncertainty in the emissivity estimate is established along with a model that qualitatively describes surface oxidation. The procedure is expected to be useful for several manufacturing applications where it is important to control high temperatures.

  • 31.
    Hatefipour, Saeid
    et al.
    University West, Department of Engineering Science, Division of Automation Systems. saeid@termisk.se.
    Ahlberg, Jörgen
    Linköping University.
    Wren, Joakim
    University West, Department of Engineering Science, Division of Automation Systems.
    Runnemalm, Anna
    University West, Department of Engineering Science, Division of Automation Systems.
    Thermal non-destructive testing: modeling, simulation and experiments for improved localization of hidden defects2014In: The 12th International Conference on Quantitative Infrared Thermography, 2014, p. 1-8Conference paper (Refereed)
    Abstract [en]

    During the last decades, a substantial amount of research and practical work has been conducted on non-destructive testing of materials using thermography. The performed studies elucidate the potential of various types of thermal non-destructive testing (TNDT) for different materials and applications, including various types of defects. This paper presents a method for detecting in-depth defects in metallic materials and a simulation model for the heat transfer in the material. Experiments are performed on a test specimen with artificial defects (flat-bottom holes). The detection method exploits spatiotemporal analysis in order to find deviations from a model of normality, and shows novel results. Thermal modelling is performed in order to have a base-line simulation model enable us to (a) investigate affecting parameters without repeating the experiments and (b) generalize the results and extend their validity to other cases. Results show that there is an acceptable compliance between simulated and measured thermal data. 

  • 32.
    Islind, Anna Sigridur
    et al.
    University West, School of Business, Economics and IT, Divison of Informatics.
    Lundh Snis, Ulrika
    University West, School of Business, Economics and IT, Divison of Informatics.
    Learning in home care: a digital artifact as a designated boundary object-in-use2017In: Journal of Workplace Learning, ISSN 1366-5626, E-ISSN 1758-7859, Vol. 29, no 7-8, p. 577-587Article in journal (Refereed)
    Abstract [en]

    Purpose: The aim of this paper is to understand how the role of an mHealth artifact plays out in home care settings. An mHealth artifact, in terms of a mobile app, was tested to see how the quality of home care work practice was enhanced and changed. The research question is: In what ways does an mHealth artifact re-shape a home care practice and how does this affect the interaction between caregivers and the elderly and learning opportunities for the caregivers? Design/methodology/approach: An action research approach was taken and the study was conducted in a home care organization in a Swedish municipality. The data were collected through semi-structured interviews and observations that were conducted during home visits. Concepts of learning and boundary objects were used to analyze and distinguish interactions and conversations with the mHealth artifact. Findings: The study shows how an mHealth artifact is re-shaping a home care practice and how this affects interactions and identifies learning opportunities. Views on the mHealth artifact as a designated boundary object as well as a boundary object-in-use must co-exist. Originality/value: The study provides qualitative descriptions from using an mHealth artifact for home care, which is an emerging area of concern for both research and practice. It focuses on the interactional and organizational values generated from the actual use of the designed mobile application. © 2017, © Emerald Publishing Limited.

  • 33.
    Jalo Olsson, Sara
    et al.
    University West, Department of Engineering Science.
    Wulkan, Martin
    University West, Department of Engineering Science.
    Förbättringsförslag till avemballeringsfixtur och materialhantering2011Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport behandlar förbättringsförslag samt åtgärdsförslag för en avemballeringsfixtur och materialhantering. Avemballeringsfixturen används för att separera ett plåtparti från pall när plåtpartiet ska lastas in till Swegons automatlager. Vid projektets start framkom det att avemballeringsfixturen inte hade genomgått en riskanalys. Detta medför en ökad risk för olycksfall då operatörerna utför sitt arbete. Det framgick även att det inte fanns några arbetsinstruktioner tillgängliga för operatörerna. Saknaden av arbetsinstruktioner gör att operatörerna inte utför arbetsmomenten på ett optimalt sätt.

    Målet med projektet var att lokalisera riskerna med avemballeringsfixturen och materialhanteringen och ge förslag på åtgärder som minimerar/eliminerar dessa. Detta gjordes genom att ta fram lösningar för ombyggnation av befintlig avemballeringsfixtur och att presentera lösningar för en säkrare materialhantering.

    Efter genomförd feleffektsanalys och arbetsmiljöanalys togs ett flertal åtgärdsförslag fram. Huvudområdena som åtgärdsförslagen berör är fixturens konstruktion, avemballeringsfixturens helhet samt operatörernas arbetsområde. De olika åtgärderna inom respektive huvudområde fokuserades på att öka operatörernas och medarbetarnas säkerhet samt att åtgärdsförslagen ska göra operatörernas arbetsmoment lättare och smidigare. Åtgärdsförslagen har i denna rapport diskuterats för att förutsäga vilken effekt de kommer att ge i form av en säkrare arbetsmiljö för operatörerna och medarbetarna.

  • 34.
    Jenkins, Samantha
    et al.
    University West, Department of Economics and IT, Division of Computer Science and Informatics.
    Ayers, P. W.
    McMaster University, Hamilton, Department of Chemistry.
    Kirk, Steven R.
    University West, Department of Economics and IT, Division of Computer Science and Informatics.
    Mori-Sánchez, P.
    Duke University, Durham, Department of Chemistry.
    Marti­n Pendás, A.
    Universidad de Oviedo, Departamento de Química Física y Analítica.
    Bond metallicity of materials from real space charge density distributions2009In: Chemical Physics Letters, Vol. 471, no 1-3, p. 174-177Article in journal (Refereed)
  • 35.
    Jiang, Janna
    University West, Department of Engineering Science, Division of Production Engineering.
    Modelling of mechanical properties of MAX-phase materials2009Licentiate thesis, comprehensive summary (Other academic)
  • 36.
    Johansson, Lars-Olof
    et al.
    Halmstad University, Halmstad.
    Lundh Snis, Ulrika
    University West, Department of Economics and IT, Divison of Informatics.
    Dynamics in a innovation boundary context: exploring an living lab process from a community of practice perspective2011In: Proceedings of OLKC 2011, Organisational Learning Knowledge Capabilities Conference, Hull, England, UK., OKLC , 2011, p. 1-15Conference paper (Refereed)
    Abstract [en]

    This paper is based on a living lab process, which is an open, user-centric, innovation approach, where several actors from industry, user groups and academia are involved. The research question is: How can a boundary context, such as a living lab process, be nderstood and facilitated from a community of practice perspective? We aim to describe and analyze the dynamics in an innovation boundary context based on a living lab process. An an action-oriented research approach was applied and the empirical results are from The Find Project (TFP), with the aim of customizing an ICT product based on the needs of a user group. The findings are analyzed from a community of practice perspective where the three different communities i) researchers from Halmstad Living Lab (HLL), ii) ICT developers (ICTD), and iii) next of kin's to demented elderly persons (NOKD) represented the unit of analysis. The analysis indicates several boundary situations that played a vital role for the innovation process. The contribution of our research to innovation theory is a process model describing the dynamics in an innovation boundary context with regard to boundary objects-in-use as well as brokering. The process highlights two different levels of brokering: i) inner-level brokering; and ii) outer-level brokering.

  • 37.
    Johansson, Lars-Olof
    et al.
    Halmstad University, Halmstad.
    Lundh Snis, Ulrika
    University West, Department of Economics and IT, Divison of Informatics.
    Svensson, Lars
    University West, Department of Economics and IT, Division of Computer Science and Informatics.
    Dynamics in an innovation boundary context: exploring a living labprocess from a community of practice perspective2011In: Proceedings of IRIS 2011: TUCS Lecture NotesNo 15, October 2011 / [ed] Leino, Timo, Turku: Turku Centre for Computer Science , 2011, p. 1-Conference paper (Refereed)
    Abstract [en]

    This paper is based on studies of a living lab process, which is an open, user-centric, innovation approach, where several actors from industry, user groups and academia are involved. We aim to describe and analyze the dynamics in an innovation boundary context based on a living lab process. An action-oriented research approach was applied and the empirical results are from The Find Project (TFP), with the aim of customizing an ICT product based on the needs of a user group. The findings are analyzed from a community of practice perspective where the three different communities i) researchers from Halmstad Living Lab (HLL), ii) ICT developers (ICTD), and iii) next of kin's to demented elderly persons (NOKD) represented the units of analysis. The analysis identified several boundary situations that played a vital role for the innovation process. The contribution of our research to innovation theory is a process model describing the dynamics in an innovation boundary context with regard to boundary objects-in-use as well as to brokering. The research highlights two different levels of brokering: i) product/service brokering; and ii) process brokering.

  • 38.
    Khorram-Manesh, Amir
    et al.
    Unit of Security and Preparedness, Former Prehospital and Disaster Medicine Center,Gothenburg,Sweden..
    Berlin, Johan
    University West, Department of Social and Behavioural Studies.
    Ljung Roseke, Lina
    Psychology Unit, Närhälsan, Borås, Sweden.
    Aremyr, Johan
    Unit of Security and Preparedness, Former Prehospital and Disaster Medicine Center,Gothenburg,Sweden..
    Sörensson, Josef
    Unit of Security and Preparedness,Former Prehospital and Disaster Medicine Center,Gothenburg,Sweden..
    Carlström, Eric
    Unit of Security and Preparedness, Former Prehospital and Disaster Medicine Center,Gothenburg,Sweden..
    Emergency Management and Preparedness Training for Youth (EMPTY): The Results of the First Swedish Pilot Study.2018In: Disaster Medicine and Public Health Preparedness, ISSN 1935-7893, E-ISSN 1938-744X, Vol. 12, no 6, p. 685-688Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: To examine the impact of a simulation training in raising a group of young students' personal and situational awareness in disasters and emergencies.

    METHODS: In total, 25 young students participated in two simulation scenarios representing two actual events, fire, and shooting, using a combination of two validated simulation training (Emergency Management and Preparedness Training for Youth [EMPTY]). The changes in their knowledge and awareness were evaluated by using questionnaires and the whole simulation was evaluated by three independent observers and a reference group.

    RESULTS: New concepts of emergency management, for example, evacuation, and barricading, could be trained in a safe environment. There was a significant increase in students' personal and situational awareness and their active engagement in the management of emergencies.

    CONCLUSION: EMPTY could raise the youth basic knowledge and ability to understand the concept of preparedness by being mentally prepared, available for collaboration, gaining a higher confidence, understanding the physical and psychological consequences of a major incident and the importance of their own safety. (Disaster Med Public Health Preparedness. 2018; page 1 of 4).

  • 39.
    Lennartson, Bengt
    et al.
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Sikström, Fredrik
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Christiansson, Anna-Karin
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Sampled-data Hcontrol applied to the choice of controller order and sampling rate2010Manuscript (preprint) (Other academic)
  • 40.
    Markocsan, Nicolaie
    University West, Department of Engineering Science.
    Recent developments in coatings for gas turbines - TBC´s and other advanced coatings.2009In: Advanced in Surface Engineering Seminar: University of Techology, Tampere Finland, 19-23 Oktober, 2009Conference paper (Other academic)
  • 41.
    Markocsan, Nicolaie
    et al.
    University West, Department of Engineering Science, Division of Process and Product Development.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Vuoristo, Petri
    Overview of thermal spray activity in the European Nordic countries2010In: Proceedings of the 4th International Conference – Innovative technologies for joining advanced materials, ISSN 1844-4938, p. 109-115Article, review/survey (Refereed)
  • 42.
    Meng, Liuchun
    University West, Department of Economics and IT, Divison of Informatics.
    Risk Management in M-Commerce projects: A Case Study of M-Commerce project in Trollhättan2012Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    Due to its inherent characteristics such as ubiquity, personalization, flexibility, and dissemination, mobile commerce promises business unprecedented market potential, greater productivity and higher profitability. With this in mind, it is perhaps not surprising that mobile commerce is growing much faster than its fixed counterpart. Unlike e-commerce, m-commerce is personalized and there is a need for a novel approach to evaluating risk management in m-commerce projects.

    Result in the increase of risks management in m-commerce. Besides the business core activities, the increased use of derivative products by both financial and non-financial institutions and recent events or scandals continue to demonstrate the need for enhanced standards and processes of control over risk.

    In this thesis, I attempt to introduce a new method for performing risk analysis studies by effectively utilizing the existing risk management process framework with adoptions of analysis approach in m-commerce projects. It will provide a sequencing of the core part of the risk management process into sub-processes for identify context, identify risks, analyse risks, evaluate risks and treat risks in different respects of m-commerce. Moreover, it seems that the integration of risk management process and some analysis method indeed provided very useful new insights.

    To be able to fulfil the purpose of study, qualitative research method was considered, using an inductive approach of a single case study of m-commerce project in Trollhättan with m-commerce related research literature and scenario for development of restaurant in university west as source of data.

    Based on the analysis, a number of observations were put forward in the conclusion. To begin with the strategy in relation to management structure will be considered. In addition, the role of information technology security is considered in risk management. Meanwhile, the good governance and risk management according to m-commerce application in risk management system and corporate governance are included in the discussion.

    In attempt of risk management in the m-commerce projects, this thesis examines the issues in one case of m-commerce project in Trollhättan not only information secure issues and some technical viewpoints in m-commerce project but also from the project management's perspective.

    The contribution of the thesis will be introducing a new framework/module for performing a risk analysis studies in m-commerce projects domain and a proposal for risk management in the m-commerce projects case of Trollhättan.

  • 43.
    Mossudd, Frida
    University West, Department of Engineering Science.
    Potential improvements for launches at Autoliv Sweden AB, focusing on the purchasing process2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    During the summer 2012 a bachelor’s thesis was performed at Autoliv Sweden AB inVårgårda regarding potential improvements on launches, with focus on the purchasingprocess. The activities that were needed to be able to reach the main goal, proposals ofpotential improvements, were divided into three interim goals. The interim goals can beseen as activities along the way containing necessary information that was needed to beable to come up with potential improvements.

    The approach for the thesis was to first do a literature review on value stream mapping, how development projects at Autoliv Sweden AB are performed and on launches in theautomotive industry based on scientific articles. After the literature review a case study wasmade, using value stream mapping as a tool, on one development project at AutolivSweden AB for investigation of the launch. The result of the case study was presented intwo maps over the administrative stream for the components in the development project;one according to project time plan and one according to how the activities in the launchactual were performed.

    Based on the literature and the maps from the case study, three potential improvements, that would be relatively easy and inexpensive to implement, were found; (1) Involve thesupplier more and at an earlier stage in the development project, (2) involve the Logisticsdepartment more and (3) implement control level definition on the development projectsas well, not just the parts.

    The conclusion for this thesis was that if Autoliv Sweden AB decides to implement allproposed improvements both money and time will be saved.

  • 44.
    Mård, Mathias
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Automation i Distributionsnät2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    As a part of Göteborg Energi’s work towards a smarter electric grid, the company has chosen to investigate the possibilities of automation in their middle voltage grid. In Europe, there are example cases where these technologies already are installed which many articles on the CIRED conference 2011 proved. Netcontrol Oy in Finland has, together with Tekla, created an automated SCADA system that Vattenfall in Finland today uses. The grid mainly consists of 10 kV open loop fed city grid and this automation is mainly designed for this type of grid. The intention of the automation is to when a fault occurs, the automation disconnects the faulted cable in the loop and then reconnects, this in as little time as possible in order to not make customers suffer.There are several different theories about how automation can be implemented, the two main principles are local automation and centralized automation. The local automation is implemented at station level with fault detectors that communicate with each other and thus disconnects a fault in the circuit using logic steps. This is the fastest option and Göteborg Energi has already installed several devices in the grid, which could make this option possible to realize. The other alternative is to let the SCADA do the sectionalizing using information from the indicators in the loop. This poses a problem though when the system becomes more complex. The operational staff might have problems with letting the SCADA make its own decisions and thereby lose control over the events in the grid. What the system could do instead is to make a suggestion on how the operational staff should handle the situation. However, the fault durations in this case will end at its best around 2-5 minutes and this makes the customer suffer for a longer time than the earlier principle.Hence, local automation is recommended, partly because it is today implemented in the grid and also because the fault duration is much shorter. This option can, with today’s technology disconnect a single-phase to ground fault without a power failure, and thus does no customer suffer during the fault. This should be supplemented with some sort of residual current compensation of the earth fault in order to remove the active fault current, thus minimizing the probability of a double earth fault or short circuit. Göteborg Energi should contact the suppliers of these devices and find out what they consider appropriate, and implement the technology in a loop as a pilot project to investigate its function.

  • 45.
    Nilsson, Jim
    et al.
    University West, Department of Engineering Science.
    Ericsson, Mikael
    University West, Department of Engineering Science.
    Danielsson, Fredrik
    University West, Department of Engineering Science.
    Virtual Machine Vision in Computer Aided Robotics2009In: Emerging Technologies & Factory Automation, 2009, p. 1-8Conference paper (Refereed)
    Abstract [en]

    In this paper a concept for Virtual Machine Vision is proposed using a commercial Computer Aided Robotics software called RobCad. The system utilizes ideal virtual cameras and lights for the simulation of a real vision system. Sensory data is sent to a vision software for data analysis. The Virtual Machine Vision together with the simulation model can be used to offline programming of a vision system. Experiments have been performed by capturing images of a test piece both in the virtual environment and in a physical experimental rig. To evaluate the concept, image analysis has been performed on these images using the same vision software. The results from the vision analysis of both the virtual and the real images are compared and show good agreement. The proposed system seems to be very promising and further development is ongoing.

  • 46.
    Pejryd, Lars
    et al.
    University West, Department of Engineering Science.
    Beno, Tomas
    University West, Department of Engineering Science, Division of Production Engineering.
    Isaksson, Marina
    CAPE.
    Machining aerospace materials with room-temperature and cooled minimal-quantity cutting fluids2011In: Proceedings of the Institution of mechanical engineers. Part B, journal of engineering manufacture, ISSN 0954-4054, E-ISSN 2041-2975, Vol. 225, no 1, p. 74-86Article in journal (Refereed)
  • 47.
    Ryberg, Anders
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Camera Modelling and Calibration with Machine Vision Applications2010Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Camera modelling and calibration are important parts of machine vision. They can be used for calculating geometric information from images. A camera model is a mathematical projection between a 3D object space and a 2D image. The camera calibration is a mathematical procedure calculating parameters of the camera model, usually based on several images of reference points. These fundamental parts of machine vision are improved in this thesis. One large part is the development of a generic camera model, GCM, that is accurate, computationally efficient and can be used for both conventional, fisheye and even catadioptric cameras. Different models were used in the past for conventional and  omnidirectional cameras and this is a well-known problem, the solution of which is described in this thesis. The accuracy of camera models is improved by introducing new ways of compensating for different distortions, such as radial istortion, varying entrance pupil point and decentring distortion. Calibration is mproved by introducing newmeans of calculating start estimates of camera parameters, from analysing shapes, sizes and positions of the reference points in the images. These start estimates are needed in order to make the calibration converge. Methods for calculating better reference centre points than the centres of gravity are developed in order to increase the accuracy further. Non-trivial null spaces that occur during calibration are identified. Awareness of these improve the calibration. Calibrations with different camera models are implemented and tested for real cameras in order to compare their accuracy. Certain models are better for certain situations, but the overall performance and properties are favourable for the GCM. A stereo vision welding robot system is developed, using the new model. It determines the geometry of a 3D weld joint, so that a robot can follow it. The same system is implemented in a virtual environment using a simulation software. Such simulation is important since it makes it possible to develop robot vision systems off-line.

  • 48.
    Ryberg, Anders
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Ericsson, Mikael
    University West, Department of Engineering Science, Division of Production Engineering.
    Christiansson, Anna-Karin
    University West, Department of Engineering Science, Division of Production Engineering.
    Eriksson, Kenneth
    University West, Department of Engineering Science, Division of Land Surveying and Mathematics.
    Nilsson, Jim
    University West, Department of Engineering Science.
    Larsson, Matthias
    University West, Department of Engineering Science.
    Stereo vision for path correction in off-line programmed robot welding2010In: Proceedings of the IEEE International Conference on Industrial Technology, 2010, p. 1700-1705Conference paper (Refereed)
    Abstract [en]

    The paper describes a versatile machine vision system for correcting off-line programmed nominal robot trajectories for advanced welding. Weld trajectory corrections are needed due to slight variations in weld joints. Such variations occur naturally because of varying tolerances in parts and to heat induced deformations during earlier weld sequences. The developed system uses one camera and a weld tool mounted on the robot hand. As a first step, the whole system, including the camera, is calibrated. Then the system takes images of the weld joint from different positions and orientations, and determines the weld joint geometry in 3D using a stereo vision algorithm and a novel camera model. The weld trajectory is then updated in the robot control system, and weld operation is performed. These steps are repeated for all weld sequences of the work piece. The strategy has successfully been demonstrated for a standard industrial welding robot and a standard FireWire CMOS camera. The maximum deviation of the trajectory found by the system compared to a reference (coordinate measuring machine) is 0.7 mm and the mean deviation is 0.23 mm. Thus, the system shows high potential for industrial implementation. ©2010 IEEE.

  • 49.
    Safi, Baset
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Comparison between Leased Fiber, MPLS and VPN in the scope of Speed, Cost and Security2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This is a thesis about how speed, cost and security differs between Leased Fiber, MPLS and VPN technologies. To connect different networks across a geographical site have become common in todays society. This is why when enterprises have multiple branches across a state or a country, they would definitely be wanting to connect all these branches together to facilitate data transfer and access between them in order to accelerate the speed of business transactions.

    Nowadays almost all of the businesses have got one or more branch offices which are connected somehow to share services or resources. To fulfil this task there are some different technologies that can be used. Through this study it will be discussed what each technology is capable of.

    This study specially focuses on speed, cost and also how secure these different solutions are. Information about these different techniques have been gathered through different document studies, articles, research studies, service providers and internet to obtain a more accurate result.

    The result of this study shows that Leased Fiber are the most secure, reliable and expensive at the same time as compared to cloud services such MPLS and VPN. However, the cloud services are implemented by most of the enterprises. The main reason is that this solution is cheaper and encryption is used to provide security and integrity. The only drawback is that the link is shared by different nodes.

  • 50.
    Sigvant, Mats
    et al.
    Volvo Cars.
    Mattiasson, Kjell
    Chalmers Tekniska Högskola.
    Larsson, Mats
    University West, Department of Engineering Science, Division of Production Engineering.
    Determination of the formability of DP-steels by a combination of experimental methods and FE-simulations2010In: International Conference of International Deep-Drawing Research Group : IDDRG 2010: Austria, Graz, 31May - 2 June, Graz: Verlag der Technischen Universitat Graz , 2010, p. 195-204Conference paper (Other academic)
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