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  • 1.
    Abudaher, Mohammed
    et al.
    University West, Department of Engineering Science, Division of Computer and Electrical Engineering.
    Alomari, Kamal
    University West, Department of Engineering Science, Division of Computer and Electrical Engineering.
    Energieffektivisering i köpcentret Sisjö Entré i Göteborg2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Energy efficiency means that energy is used in an efficient way that impacts positively on the environment and society.

    Sisjö Entré is a shopping center which has an annual energy consumption of 1 865 270 kWh, and according to Energy Authority, the recommended value is 1 530 000 kWh per year. That means that energy consumption at the center should reduce by approximately 18 % to comply with the recommended value. The mall consists of 17 stores and the thesis examines five stores which are Toys Я Us, Rusta, Burger King, Babyproffsen and Webhallen. Measurements are taken on ventilation and lighting installations with the aim of studying the loads in the stores that consume the most energy. The goal is to come up with suggestions of actions to reduce energy consumption and costs.

    We concluded that lighting consumes the most energy in the warehouses; Toys Я Us, Rusta, Babyproffsen and Webhallen, while the largest load in the restaurants (Burger King) is the kitchen, which accounts for 75 % of the restaurants total consumption.

    In Rusta, we discovered that the electricity meter showed a lower value than the true consumption. After investigation, we concluded that the fault could be either in the electricity meter or in its current transformer and must be addressed.

    We have given a proposal to replace parts of the existing lighting installations, and given suggestion for sectioning certain parts in some stores. Further, we have given suggestions for reducing operating times on the ventilation units.

    Based on the above proposals and energy calculations, we concluded that these five stores has the potential to reduce the annual energy consumption from 1 865 270 kWh to 1 576 670 kWh, leading to a reduction by 15.5 %. This reduces costs by about 228 000 SEK per year

  • 2.
    Adolfsson, Sebastian
    University West, Department of Engineering Science, Division of Production System.
    RatSLAM with Viso2: Implementation of alternative monocular odometer2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this work, a ROS (Robot Operating System) version of OpenRatSLAM, [1] [2], was tested with Viso2 [3] as an alternative monocular odometer. A land based rover [4] was used to perform data acquisition and a remote control tool was developed to facilitate this procedure, implemented as ROS nodes on both Ubuntu 16.04 and on Android 7.0.  An additional requirement that comes from using Viso2 is the need for camera information together with the image stream, which might require camera calibration. A ROS node to manually add this camera information was made as well as a node to change the generated odometry message from Viso2 to a form that RatSLAM uses. The implemented odometer uses feature tracking to estimate motion, which is fundamentally different to matching intensity profiles which the original method does and can hence be used when different properties of the visual odometry function is desired. From experiments, it was seen that the feature tracking method from Viso2 generated a more robust motion estimate in terms of real world scale and it was also able to better handle environments of varying illumination or that contains large continuous surfaces of the same colour. However, the feature tracking may give slight variations in the generated data upon successive runs due to the random selection of features to track. Since the structure of RatSLAM gives the system ability to make loop closures even with large differences in position, an alternative odometry does not necessarily give a significant improvement in performance of the system in environments that the original system operates well in. Even though both algorithms show difficulty with estimating fast rotations, especially when the camera view contains areas with few features, the performance improvement in Viso2 together with its ability to better maintain the real-world scale motivates its usefulness.  The source code, as well as instructions for installation and usage is public.

  • 3.
    Adolfsson, Sebastian
    University West, Department of Engineering Science, Division of Production System.
    RatSLAM with Viso2: Implementation of alternative monocular odometer2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this work, a ROS (Robot Operating System) version of Open RatSLAM, [1] [2], was tested with Viso2 [3] as an alternative monocular odometer. A land based rover [4] was used to perform data acquisition and a remote control tool was developed to facilitate this procedure, implemented as ROS nodes on both Ubuntu 16.04 and on Android 7.0.An additional requirement that comes from using Viso2 is the need for camera information together with the image stream, which might require camera calibration. A ROS node to manually add this camera information was made as well as a node to change the generated odometry message from Viso2 to a form that RatSLAM uses. The implemented odometer uses feature tracking to estimate motion, which is fundamentally different to matching intensity profiles which the original method does and can hence be used when different properties of the visual odometry function is desired. From experiments, it was seen that the feature tracking method from Viso2 generated amore robust motion estimate in terms of real world scale and it was also able to better handle environments of varying illumination or that contains large continuous surfaces of the same colour. However, the feature tracking may give slight variations in the generated data upon successive runs due to the random selection of features to track. Since the structure of RatSLAM gives the system ability to make loop closures even with large differences in position, an alternative odometry does not necessarily give a significant improvement in performance of the system in environments that the original system operates well in. Even though both algorithms show difficulty with estimating fast rotations, especially when the camera view contains areas with few features, the performance improvement in Viso2 together with its ability to better maintain the real-world scale motivates its usefulness. The source code, as well as instructions for installation and usage is public

  • 4.
    Aguilar Gómez, Raquel
    University West, Department of Engineering Science, Division of Automation Systems.
    Investigation of a Flexible Manufacturing Scenario for Production Systems: Case study: GKN Aerospace Company2015Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nowadays the globalization of the market has a direct impact to the companies. On one hand, gives them the opportunity to spread their business but on the other hand increases the competition and the efforts to succeed. This project is pursuing to investigate and design a system capable to take upon and optimize the production within functional shops by in-troducing automation. Although the system it would be a standard solution for the functional shops, a case study for GKN Aerospace Company with its specifications has been carried out. The task become trickier due to the aeronautic sector requires a lot of work and effort to produce their products. The items and materials are expensive as well as the processes and treatments thus the introduction of automation is quite complex. This case study has accom-plished a research through the concepts and options to introduce automation within this production process. Taking under consideration the costs and efforts that would demand the investment for automation, the project propose a new and innovative manufacturing system "Move & Play", suitable with the features and requirements GKN Aerospace Company may need.The system proposed has been designed regarding to features such as movability, modularity and flexibility. These features have been considered essentials in order to make the system worth it and cost effective. The job-shop approach that the company use in its production contemplate the continuous change of products and introduction of new ones. Hence, the idea is to use the "Move & Play" system when it is required along the production. As a consequence, this system will create a "local product flow" along that point in the production that will organize the rest of the production or "global flow". Moreover it is expected to apply the concept of "plug-in" the processes that the system need at each time and therefore give flexibility to the system. With that purposes, the work has studied three different designs of the "Move & Play" system. Each design have considered different aspects and disposition. These designs have been compared according with criteria such as geometrical, the capacity and investment needed and the cycle time spent. Finally a conclusion on which design is the most suitable has been stated as well as a future work to continue with the work has been proposed.

  • 5.
    Akiki, Cesar
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Torstensson, Daniel
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Hur routingtabellens storlek påverkar paketets fördröjning i en router eller L3 switch2017Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    The internet is growing, and more devices are becoming connected for each day that passes by. This will increase the number of routes in the routing-table on the routers and L3 switches and as they are increasing it will affect the delay on the packets traversing between the source and destination. Or does it matter? Does the size of a routing table affect the delay? In this study, we have researched if there is a difference in the delay on the packets in a comparison to the size of the routing-table and this is compared between a router and L3 switch. During this study, we have been using a desktop computer that has two network interfaces installed in it and is connected to a router or L3 switch. We used three different programs on the computer that have been very helpful for completion of our work: Wireshark, to monitor and capture packets and the time between the two network interfaces on the desktop computer. Tftpd32, to copy the running-configurations from the router or L3 switch over to the desktop computer and back. Ostinato, is used to generate and send out packets on the network. All the results we got from our tests point to that there is no increase in delay no matter how much the routing-table is increasing. These results challenge previous studies that tells us the opposite, that the increase of a routing-table does have an increase in delay.

  • 6.
    Al Hayani, Musab
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Offline Programming of Robots in Car Seat Production2013Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Company Purtech in Dals-Ed manufactures molded polyurethane (PUR). Examples of products that include polyurethane are car seats. Robots are used to fill the molds with PUR and to apply the release agent (wax) in the empty molds.

    Turning from online programming into a graphical offline programming of release agent spraying robots is going to simplify the process by:

    1. Applying less of release agent to avoid polluting environment, to produce an easier removal of moulds, for the sake of homogeneous moulds and for economical saving in the cost of release agent
    2. Adaption of spraying paths to variation in production speed.
    3. Programming of complex spraying trajectories to deal with sharp geometrical subsurface
    4. Decreasing onsite programming time (when program a new workpiece or modify an old one); so that robots would be free for production.

    While turning into offline programming brought the challenges of:

    1. Impact of variation in the production speed
    2. Lack of 3D models of workcell’s equipments
    3. Robot joint configuration when paths and robtargets are in move.
    4. Physical Joint limits, Singularities & Reach limits
    5. Collisions within the cell space.

    At the end, the following objectives are successfully met:

    1. Adaption of spraying programs to variation in production speed by developing and embedding a method in those programs.
    2. Graphical offline generation of spraying trajectories and optimization of those trajectories to the Purtech condition of spraying allowed time for each carrier.
    3. Simulation of release agent spraying process; and producing of a well structured RAPID program that reflect the simulated process.

              

  • 7.
    Albadri, Rand
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Jämförande analys av driftsäkerhet medRTU och PLC2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis will make a comparative analysis of the operation safety of the wire connection to Remote Terminal Unit (RTU) and Programmable Logic Controller (PLC) with bus-controller. The report describes the basic description of the difference between these two systems and will explore which is safer and more economic with consideration to qualification according to Swedish energy companies' guidelines for dam safety (Ridas).Through course literature, ABB Bok, internet web sits and interviews with Skellefteå Kraft AB staff the result of this report have been created.The report results prove that PLC with bus-controller will operate operationally safe and profitable compared to wire connection to RTU. Results also showed that there is nothing which prevents to install bus-controller according to RIDAS but certain features should be installed.

  • 8.
    AlNabulsi, Yasan
    University West, Department of Engineering Science, Division of Production System.
    Robot motion control based on 3D mouse tracking2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The manufacturing industry and associated systems are being developed in an increasing manner to cover the market needs, where the manufacturing companies are continuously racing and competing to achieve high productivity rate and better production quality. In this thesis work, an advanced method for motion control of industrial robots has been investigated and implemented. This method is based on motion tracking of a 3DSpaceMouse, which was used to perform movements by the operator. The benefits and disadvantages of this method were discussed in this thesis work. It mainly showed a high accuracy in response to the motion applied by the 3DSpaceMouse, and a great stability regarding the programming environment that was used to build it. The movements applied by the 3DSpaceMouse were successfully captured and stored in variables in the programming platform. The capturing and storing process was successfully created as a package and prepared to be exported for usage by other software. Complete simulation was performed for an industrial robot, and successful communications among the various hardware and software components of this solution were accomplished. This has formed a complete integrated solution that has also included a user-friendly HRI. This HRI made it easy and simple to track the motion control processes and establish connections with the robot controller. Thus, it can be considered a feasible solution for motion control of industrial robots, which can be used by the manufacturing companies. Several tests and verification processes were carried out to obtain accepted results and to succeed in implementing a working model. Some errors and unexpected events have appeared during the work, which required handling in order to achieve a working integrated system.

  • 9.
    Andersson, Andreas
    University West, Department of Engineering Science, Division of Automation Systems.
    Utredning av variablerna som påverkar storleken på brytspänningen i lindningskopplare2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The recovery voltage is the voltage that occur when the transition resistor in the tap-changer leaves its previous position during an operation cycle. The amplitude of the recovery voltage depends on the leakage inductance.

    If the leakage inductance is unknown, the recovery voltage can instead be calculated using a FEM-program called ACE (internal ABB-program) in conjunction with Mathcad. First, the reactances between the windings are calculated in per unit (p.u) using ACE and they depend on the winding layout. It is time consuming to use ACE and Mathcad and the task has been to investigate the parameters that affects the recovery voltage and to develop a simplified calculation of it.

    Through simulation using ACE of a number of different winding layouts one soon comes to the conclusion that there are simply too many parameters affecting the reactances. Although the simplified calculations that despite this has been developed, they soon prove to be too rough to be useful. Mathcad is even more complex with heavy calculations that are not easy to grasp.

    However, this thesis has given more knowledge about the way the reactances are affected by the geometry of the windings, even though it was not possible to in a reasonable way simplify the calculation of ACE and Mathcad.

  • 10.
    Andersson, Andreas
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Hägerström, Martin
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Beredningsarbete på Galtö med undersökning av miljöaspekter vid ombyggnad av distributionsnät2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis deals with the practices of processing work. The work is being performed with TROLK El & Tele AB and is ordered by Ellevio AB. The area that the work is carried out at is Galtö in Tanum. The area includes about 10 km cable installation, 4 substations and 5 satellite substations and three low voltage areas where the grid are going to be rebuilt. Ellevio AB has invested in this project as they want to weather proof and ensure a high quality of the power delivery. The preparatory work that is presented as a proposal TROLK can continue to work with and apply for the relevant permits. These permits have been accounted for when this work has been prepared. The existing overhead line will be dismantled when the new grid has been connected. The overhead line is approximately 5.2 km long and includes nine pole mounted transformers. The work is based on the project documents that Ellevio has provided, though some changes have been made where necessary.

    The thesis also identifies the environmental aspects arising from the dismantling of an overhead power grid and investigates alternative solutions to reduce the environmental impact. When TROLK are working with projects commissioned by Ellevio they are using the environmental plan handed by Ellevio. The environmental plan have been studied and compared with other actors' environmental plans in order to identify potential improvements. The study identified that the greatest environmental aspects is the hazardous waste of creosote impregnated power poles and PCB-contaminated oil. No major improvements in the waste management has been. Focus has then been to examine options to replace the hazardous materials for new installations. It has been found several different options to the creosote power pole that all have different effects on the environment and there are therefore no obvious alternative. PCB-contaminated oil are currently not allowed in the grid but as it means a big expense to replace dispensations has been distributed to the owners of the power grid until it has been rebuilt.

  • 11.
    Andersson, Andreas
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Leinonen, Markus
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Projektering och elkvalitetsstudie av laddstationer för elfordon2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the last couple of years, the evolution of plug-in electric cars has contributed to an increasing need of well-built charging infrastructure. This does not only require that the fair amount of charging stations needs to match the increasing demand, but the growing amount of charging station could also affect the power quality in the grid itself due to the technology used today.

    The objective of the first part of the project was to deliver a complete installation plan and project basis of two AC charging stations for electric vehicles, planned in the city of Kungälv. The second part of the project was focused on studying the effects of DC fast charging of electric vehicles, with power quality in mind. This study was based on readings obtained from measuring the power quality at an existing DC fast charging station in Kungälv, as well as available publications within the area of the subject. The project planning was conducted in regards to Swedish standards and regulations, as well as to the instructions and expectations of the client, Kungälv Energi. The result was compiled and handed over to the client during the final part of the project. The resulting document contained information regarding installation, material and placement as well as approximate cost calculations.

    The power quality study was carried out on a currently installed fast charging station located in the city of Kungälv, using power quality measuring instruments provided by Kungälv Energi and Metrum Sweden AB. The result was a power quality report, compiled according to Swedish Energy Markets Inspectorate, where all requirements concerning power quality were met. The data was also analyzed manually, to further investigate the effects of DC fast charging. The study shows no immediate signs of negative impact of the power quality in the nearby grid caused by the fast charging stations within the project. There were signs of harmonics caused by the charging stations, but the presence was considered low. The usage frequency is however a major factor when investigating the power quality affection of the charging station. This results in a conclusion that is not generally applicable.

  • 12.
    Andersson, Carl Fredrik
    University West, Department of Engineering Science.
    50 kVA eller 100 kVA: En teknisk och ekonomisk jämförelse av distributionstransformatorer2010Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Rapporten utreder om distributionstransformatorer med märkeffekten 50 kVA i Vattenfall Eldistribution AB:s elnät kan avskaffas till förmån för märkeffekten 100 kVA. Transformatorer med märkeffekten 50 kVA förekommer vid nedtransformering av spänningen från 22 kV och 11 kV till hushållens huvudspänning 0,4 kV.

    50 kVA-transformatorer skiljer inte särskilt mycket från transformatorer med den högre märkeffekten i fråga om storlek och pris, och de bedöms kunna bytas ut utan större praktiska svårigheter.

    Fördelen med 100 kVA är att de elektriska belastningsförlusterna blir lägre i och med den högre märkeffekten. Dessutom innebär ett byte vissa elkvalitetsförbättringar.

    Nackdelarna med 100 kVA är att de elektriska tomgångsförlusterna är högre och att inköpspriset är högre än för 50 kVA. I övrigt kan kostnaderna likställas för de två alternativen.

    Endast kostnader för aktiva effektförluster berördes i rapporten då de ekonomiska kostnaderna för reaktiva effektförluster kunde försummas för de aktuella transformatorerna.

    För att nå ett svar på frågan om det kan vara lönsamt att avskaffa 50 kVA-transformatorerna studerades fem verkliga fall i Vattenfalls svenska elnät. Dessutom studerades eventuella elkvalitetsvinster med ett byte.

    Svaret blev att inte för något av de fem studerade fallen var det lönsamt med ett byte till 100 kVA-transformator. Rörande elkvalitetsaspekten blev svaret att ett byte visserligen innebär en skillnad men att andra faktorer oftast har större betydelse. Rapportens rekommendation blev att behålla 50 kVA-transformatorn i distributionsnätet. 

  • 13.
    Andersson, Christoffer
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Andersson, Pontus
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Beredning av distributionsnät Myren-Torseröd i Tanum2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report will focused on how the preparatory work between Myren-Torseröd in Tanum will proceed. On behalf of Ellevio AB, the preparation and construction company Trolk EL & Tele AB shall weatherproof an area between Galtö-Torseröd in Tanum. This report will only include the distribution 0,4-24 kV in the area between Myren-Torseröd. The existing overhead line network will be dismantled and replaced with underground cables. Even existing substations and pole stations to be scrapped and replaced with new ones. During the preparatory work, there have been field visits to get an overview of the field of processing operations, and to measure the position of e.g. substations. To have access to the ground the preparation worker must sign contracts with landowners, and shall also seek authorization from the County Administrative Board, the transport department and municipality. The entire preparation work in this project includes 68 customers.

  • 14.
    Andersson, H. Robert H.
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    De Blanche, Andreas
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Lundqvist, Thomas
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Flipping the Data Center Network: Increasing East-West Capacity Using Existing Hardware2017In: 2017 IEEE 42nd Conference on Local Computer Networks (LCN), 9-12 Oct. 2017, IEEE, 2017, p. 211-214, article id 8109355Conference paper (Refereed)
    Abstract [en]

    In today's datacenters, there is an increasing demand for more network traffic capacity. The majority of the increase in traffic is internal to the datacenter, i.e., it flows between different servers within the datacenter. This category of traffic is often referred to as east-west traffic and traditional hierarchical architectures are not well equipped to handle this type of traffic. Instead, they are better suited for the north-southbound traffic between hosts and the Internet. One suggested solution for this capacity problem is to adopt a folded CLOS topology, also known as spine-leaf, which often relies on software defined network (SDN) controllers to manage traffic. This paper shows that it is possible to implement a spine-leaf network using commodity-ofthe-shelf switches and thus improve the east-west traffic capacity. This can be obtained using low complexity configuration and edgerouting for load balancing, eliminating the need for a centralized SDN controller.

  • 15.
    Andersson, Helen
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Analys av ett distributionsnät i en bangård2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    An analysis of an electrical distribution system located in a railway yard have been requested by Atkins Global AB. The system includes electrical distribution to signal equipment, heating equipment for the switches and lightning for the platforms.

    The initial part of the analysis consisted of a literature study regarding requirements for this type of system and the gathering of data regarding the cables and the fuses in it. The cabling are either of the type FXQJ or AXQJ. The system is normally powered from a three-winding transformer via two centrals, the first central A1 supplies the signal equipment electricity, through the subcabinet F3, and the lightning both powered by a main voltage 400V and central B1 powers the equipment for heating the switches with the main voltage 230V. The distribution from B1 consists of two parallel cables feeding a subcabinet FS4/36.There also exists an auxiliary power supply from a smaller transformer T3, used if the main power supply should disappear.

    The remaining investigation was conducted in the calculation program MyEcodial by Schneider Electric. The investigation focused on personal safety and short current calculations. The result was a series of suggested changes regarding the fuses and cables in the system.

    The results of the investigation regarding the powering of the signal equipment was such that a recommendation to change the cable going from F3 to one of the signal cabinets to an AXQJ 3x95/29 cable and to conduct a current measurement regarding if the present 100A fuse can remain or if it should be switched to an 80A fuse. From F3 to both the main power supply and the auxiliary power supply new fuses with 200A must be put in to ensure that the cables are protected. For the powering of the lightning it was the selectivity between the fuses that was the problem since they both had the size 63A, the investigation proved that it was the lower fuse that should be replaced with a fuse with highest 50A and lowest 32A. Regarding the power supply for the heating of the switches it is once again necessary to do a current measurement to determ if it is possible to switch the present 400A fuse to a smaller one on 315A. If not then two more cables of the same size as the present ones must be installed parallel to the present ones to ensure safety for people.

  • 16.
    Andersson, Johnny
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Karlsson, Robin
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Uppstartsguide för Febdok2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete har utförts på ÅF Industry i Trollhättan. Syftet med examensarbetet är att arbeta fram rutiner och ett standardiserat arbetssätt i Febdok. Detta för att underlätta och spara tid vid användning av Febdok. Inledningsvis påbörjades framtagning av relevant teori kring den definierade problembeskrivningen tillsammans med handläggaren på ÅF. Parallellt genomfördes övningsexempel i Febdok för att gruppen skulle få en insyn i hur funktionerna fungerar. Rapportens teoridel behandlar de mest problematiska- och tidskrävande funktionerna i Febdok så som UPS:er, kortslutningsströmmar och selektivitet. Det för att ge en förståelse om bakgrunden till funktionerna. Ett beräkningsexempel på ett fiktivt nät gjordes för att kunna verifiera en överslagsräkning som används på ÅF för att beräkna ett ungefärligt värde på minsta felström. Denna minsta felström erhålls vid enfasig jordslutning och definierar utlösningsvilkoret. Maximal felström delat på tre har ansetts ge ett någorlunda korrekt värde på minsta felström. Beräkningar på maximal- och minimal felström vid olika kablage jämfördes och visade att överslagsräkningen inte är att rekommendera på grund av att minsta felström ibland bli lägre. Istället bör en faktor av minst fyra användas vid överslagsräkningen för minsta felström. I avsnitt 3 i rapporten beskrivs initiala inställningar och funktioner i Febdok med föregående teori som bakgrund. Implementering av UPS:er i Febdok visade sig kräva mer datainmatning än vad som normalt går att få tag på från tillverkare. Genomsläppt energi är data som visade sig svår att få tag ifrån olika tillverkare. Vid närmare tester av programmet och dess funktioner visade det sig att genomsläppt energi inte behövs definieras i UPS-funktionen för att arbeta med selektivitet och kortslutningsströmmar längre ut i anläggningen.

    Resultatet av observationerna i Febdok och teorin visade att tumregeln som används på ÅF inte är att föredra och säkringar i en anläggning försedd med UPS bör dimensioneras efter batteridrift. Informationen och kunskaperna som samlades under arbetets gång samanställdes i en uppstartsguide för Febdok. 

  • 17.
    Andersson, Martin
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Hägerström, Martin
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Sammanställning av utbildningsmaterial om reservkraft med inriktning dieselaggregat2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today's society is composed of a constant energy dependency to get all functions of the modern society to function, a power failure can be devastating. Even though Sweden has a strong power grid, the requirement to always have access to electricity has opened up a market for back-up power. The aim of this work was to create material that could be used in educational purpose and for the reader to get a basic understanding of back-up power with focus on diesel generated power. The course material consists of recommendation of content in the form of page references from sources that fit well in the compilation ofeducation material in the form of a compendium. The compendium is supplemented with a layout of a PowerPoint presentation that can be used for educational purposes. By studying the relevant sources, we have deepened in our topic diesel generated power and have picked out page references, in accordance with the agreement regarding the school copy law, which we consider to be a good fit for the creation of a compendium. We have also created a foundation to a PowerPoint that can facilitate the creation of lecture material. This report explains the structure of a diesel power generator and what is important to consider when sizing a power system. The report also discusses recommended maintenance as well as the requirements placed on a diesel power generator.

  • 18.
    Andersson, Robin
    et al.
    University West, Department of Engineering Science, Division of Computer and Electrical Engineering.
    Larsson, Jonas
    University West, Department of Engineering Science, Division of Computer and Electrical Engineering.
    Jämförelse av riktade reläskyddsfunktioner i impedansjordade nät2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis describes how different values on a neutral grounding resistor and an uncompensated power distribution network affect the zero sequence current and the zero sequence voltage. If the neutral grounding reactor in the power distribution network is too overcompensated or undercompensated, the directional earth-fault relay may not work. The purpose of this study is to present the advantages and disadvantages of two different earth-fault functions. The two earth-fault functions that will be compared are an admittance-based earth-fault protection and a directional earth-fault protection with angle calculation between the zero sequence current and the zero sequence voltage.

    The capacitive earth-fault currents have increased in the distribution stations because the overhead lines are replaced with underground cables. The capacitive current must be compensated since the capacitance can cause an overcompensated or an undercompensated network. An uncompensated distribution network may cause the zero sequence current and voltage becoming too low so that the earth-fault protections do not detect an earth-fault.

    After the comparison of the two earth-fault functions it can be concluded that there is a minor difference between the both functions. There are some deviations in the test results conducted in a laboratory environment. It is not possible to state which one of the functions that is the most suitable to use in real power distribution networks, since no such tests have been conducted in this study.

    The authors of this thesis have presented some advantages and disadvantages of the two earth-fault functions

  • 19.
    Andersson, Tommy
    et al.
    University West, Department of Engineering Science, Division of Computer and Electrical Engineering.
    Lindell, Erik
    University West, Department of Engineering Science, Division of Computer and Electrical Engineering.
    Kartläggning av begränsande faktorer vid fellokalisering med pulsekometod på mellanspänningskablar2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    As the medium voltage network cables in Sweden is buried down in the earth, the demand of fault localization expertise increases. To keep downtimes in the network short, the importance of effective fault localization is necessary. This work is aimed to map and visualize limiting factors within fault localization with focus on the TDR -

    Time Domain Reflectometry. This work is a collaboration with Vattenfall Eldistribution AB.

    Problems with fault localization on medium voltage cables with the TDR have been detected. A multiple factors are contributing to this problem. The results of this study show that the cable construction is a significant part in which extent the TDR can be used. The report are also accounting for basic information about construction and types.

    The mapping also illustrates water treeing and how it affects cables in a negative way. Visualization of what causes water treeing and several actions such as triple extrusion, jacket testing and insulation testing is included in the essay. Further information about fault types, cable types, cable generations, instrument types and method types is given. All of them are affecting factors within the area of fault localization.

    Documentation is highly important for a successful fault localization procedure, which is clarified in the report. Besides documentation the cable condition and the influence on it affecting the result of fault localization is stated.

    A number of measuring methods and instruments are available to use when fault localization and testing are occurring. Every instrument has their own advantages and disadvantages. They also have their own respective area of usage. The basic principle of TDR is studied and explained accordingly. The other measuring methods, which are used in fault localization and testing, are shown more generally

  • 20.
    Andlovic, Mihael
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    How real-world IP-distribution affects load balancing2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This essay looks at how IP addresses on the last octet are distributed and how they are balanced by different load balancer algorithms. We collected the data from a data center in Sweden to get real data. The IP addresses we collected were used with a load balancer using IP source algorithms. We used 4 different algorithms in different scenarios: the entire IP address, the first 3 octets, and the last octet with and without hash between two to five links/servers. The results were that the efficiency of the algorithm depends on the setup that is being used. Each of these algorithms did not have an even distribution, when comparing between two to five links/servers. The best overall distribution that did not have any weaknesses compared to the other algorithms was Nginx that uses the Bob Jenkins hash algorithm.

  • 21.
    Andréasson, Kim
    et al.
    University West, Department of Engineering Science, Division of Computer and Electrical Engineering.
    Hagberg, Daniel
    University West, Department of Engineering Science, Division of Computer and Electrical Engineering.
    Undersökning av iBeaconannonsering via smartphoneapplikation: Objective c och ASP.NET2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This degree project is performed together with the company Sigma in relation with the education Datateknisk Systemutveckling at Högskolan Väst in Trollhättan. The purpose of this project is to examine the new technology iBeacon and study if it is to prefer over simi-lar technologies when developing a system to use for advertisement. To accomplish this, a smartphone application is developed aswell as an administration interface, to be able to perform a user test of the product with a random selection of people.

    The goal with the project is to develop a working product that can be tested and used for the examination of the hypothesis. This report explains how the project is performed and in the end, the result that the user test shows is discussed.

  • 22.
    Antoine, Galluet
    University West, Department of Engineering Science, Division of Automation Systems.
    Kinect to control robot: New ways to interact with robots2015Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The main goal of the thesis is to create a way to interact with a ABB robot by using a Kinect.The focus will be put on making the robot mimicking the user's arm movement. But otherway like voice control will be investigated.Two main part of the work are developed in this report. The first one is the software aroundthe Kinect to get the body data. The software developed provides the user a visual feedbackon what the Kinect see and allows him to choose what mode he wants to use. Two mainmode are implemented. A mimicking one which makes the robot mimicking the chosen armand a moving object mode which tell the robot to go to the user's position and set the toolas the user hand state.When all the data are gathered, they are sent to the robot using an IP socket and predefinedmessage to give him the desired order.

  • 23. Arezoomande, Daniel
    Anslutning av två vindkraftverk till befintligt nät2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis was conducted at University West in Trollhättan and Kungälv Energi AB in Kungälv. Being owner of an electrical grid, Kungälv Energi AB has the responsibility to check if the electrical grid needs to be reinforced when connecting new electricity generation facilities such as two new wind turbines. This thesis mission is to examine how the voltage quality might be affected by the connection of the wind turbines and give suggestions on how to solve eventual problems. Several alternatives will be examined for how the cables between the wind turbines and the power grid should be placed. One cost calculation will be presented. The voltage quality calculations are done through the guidelines from AMP, Anslutning av Mindre Produktionsanläggningar. Because the provider of the wind turbines has yet to be decided, necessary data has been taken from the previously connected wind turbine in Skåreby, "Vindrosen". The cost calculations are done with the help of EBR, ElByggnadsRationalisering. The cable dimension alternatives that are presented are based on costs and long term planning. These dimensions are 95mm2 and 240 (underground transmission line)- alt. 241mm2 (overhead transmission line). The thesis also includes suggestions for alternative dimensioning of the currently placed power grid at the point of interconnection for the wind turbines. All presented alternatives of the dimensioning for the cables are solely 24kV in accordance with the rest of the power grid to avoid unnecessarily high costs. It is recommended that Kungälv Energi AB does not connect the wind turbines before more thorough calculations are made in conjunction with eventual harmonic distortion measurements. This is because the equations AMP refers to are deemed imprecise due to some parameters such as cable capacitance have not been taken into consideration. It is recommended that, during the negotiations of the new wind turbines, Kungälv Energi AB limits the maximum current harmonic distortions that the wind turbine produces.

  • 24.
    Aronsson, Andreas
    et al.
    University West, Department of Engineering Science, Division of Computer and Electrical Engineering.
    Bäversjö, Jonathan
    University West, Department of Engineering Science, Division of Computer and Electrical Engineering.
    Undersökning av gratis WiFi i Göteborg2014Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    This report examines a number of free WiFi-hotspots that are offered by various companies in central Gothenburg and how they compare to the mobile networks. Traffic, capacity, channel frequencies, signal strength and acceptable use policies were all analyzed and verified.

    The readings showed that the networks were generally not utilized to their full capacity, a probable cause might be the distribution of mobile networks and that channel distribution was with a few exceptions allocated correctly according to 802.11 standards. Acceptable use policies on the networks were implemented by the larger chains but not by the smaller companies

  • 25.
    Atar, Mohammad
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Förstudie till fältbusslaboration för elkraftstillämpningar2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis describes how to develop a fieldbus lab. The lab will be part of the course Data communications with electric power applications (course code DML200) at University West. The goal and purpose of this lab will be to allow students learn how to set up, commission and troubleshoot equipment. In this context, the course also directed towards electric power technology and it is important for the Bachelor programme in electrical engineering with specialization in power electric because the course is included in the program.

    The work was aimed at developing suitable equipment which must include the appropriate number of protection relays and the necessary components for communication via ProfiBus such as PLC controllers, I/O-module, the Operation Panel. Different companies where asked about the prices of the components and a collection of quotations was made.

    The response from three out of five different companies indicated that ProfiBus is an old system. Everyone wondered why ProfiBus was chosen as a communications system over other system such as Ethernet with ModBus. According to these companies ProfiBus is an old communication system and it is expensive. It could save some money if the problem was solved with ethernet with ModBus because of the availability of the manufacturers. Finally the lab idea was illustrated with a wiring diagram.

  • 26.
    Augustsson, Per
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Mansori, Farsad
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Skapande av dynamiskt modellnät för analys av lasters beteenden vid nätstörningar2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor’s thesis is carried out on behalf of Vattenfall Eldistribution AB in Trollhättan. This work aims to make modelling of power grids for simulations, of load behaviour during perturbations, in PSS/E more effective. Modelling will be made more effective by means of programming, using the programming language Python, and also by allowing certain assumptions to be made about the grid. The idea for this work arose from a certain case, during which Vattenfall was tasked with investigating why voltage levels near an industry would not recover after a short circuit, on the transmission line feeding the industry, was cleared. Investigations demanded simulations of the disturbance to be carried out in PSS/E, to describe what had happened. To enable simulation and to make it representative, the grid and its components must be adequately modelled. Svenska kraftnät has the data nessecary for such modelling, but it is inaccessible due to confidentiality. Due to the data being confidential extensive work with modelling was nessecary. Early simulations were based on the idea that some parts of the grid can be modelled using only simplified models, and with typical, or default, values. This thesis uses that hypothesis in the programming code. The low voltage after these perturbations were caused by motors, more specifically induction motors, drawing high currents from the grid during reacceleration when the voltage starts to recover after the perturbation. This high, and mostly reactive, current causes significant voltage drops across the lines and transformers, in turn causing other motors to draw more current and further lowering voltage. The programming code, called a script, developed during this work allows the user to quickly create dynamic model data to use when conducting simulations of the dynamic behaviour of this type of loads. Modelling of the generators is done quickly thanks to the assumption that generators are located far enough away that they are barely affected by the studied disturbance. They are, for this reason, modelled using typical values. Through a graphical interface, the user then select which loads to model. For each load model, the distribution across different types of loads is specified by the user. Finally, protection relays are modelled to enable current monitoring. The script has been tested by comparisons to a reference network model created by Vattenfall. The comparisons show minor deviation between the script and the reference. This could be because the script uses default values and models less components than the reference.

  • 27.
    Augustsson, Svante
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Human and Robot Interaction basedon safety zones in a shared work environment2013Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The work explores the possibility to increase the automation along a production line by introducing robots without reducing the safety of the operator. The introduction of a robot to a workstation often demands a redesign of the workstation and traditionally the introduction of physical safety solutions that can limit the access to the work area and object on the production line. This work aims to find a general solution that can be used not only in the construction industry, but also in other types of industries to allow for an increased Human and Robot Interaction (HRI) without physical safety solution. A concept solution of a dynamic and flexible robot cell is presented to allow for HRI based on safety zones in a shared work environment. The concepts are based on one robot and the usage of a 3D camera system allowing for the design of virtual safety zones, used to control the HRI. When an operator approaches the robots work area and triggers a safety zone the robot stops its work and moves away from the operator. Based on the safety requirements and triggered zones the robot will continue to work in a new area or wait until the operator leaves the work area and then continue with the interrupted work task. This will allow the operator and the robot to work together, where the operator location controls the robots workspace. Testing and validation of the presented concept showed that the wanted functionality could be obtained. It also showed limitations to the equipment and the system used during tests and raised additional aspects of the safety for HRI. Of the detected limitations the most crucial when looking at up-time for the production line, is the camera system need of a relatively dust free environment, good and constant lighting. For the safety of the system the limitation lies in the size and placing of the safety zones in combination with the disturbance from  surrounding equipment. The presented concept has proven to work, and can be applied not only for the construction industry but for all industries with manufacturing alongside production lines with large components.

  • 28.
    Augustsson, Svante
    et al.
    University West, Department of Engineering Science, Division of Automation Systems.
    Gustavsson Christiernin, Linn
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Bolmsjö, Gunnar
    University West, Department of Engineering Science, Division of Automation Systems.
    Human and robot interaction based on safety zones in a shared work environment2014In: HRI '14: Proceedings of the 2014 ACM/IEEE international conference on Human-robot interaction, New York: Association for Computing Machinery (ACM), 2014, p. 118-119Conference paper (Refereed)
    Abstract [en]

    In this paper, early work on how to implement flexible safety zones is presented. In the case study an industrial robot cell emulates the environment at a wall construction site, with a robot performing nailing routines. Tests are performed with humans entering the safety zones of a SafetyEye system. The zone violation is detected, and new warning zones initiated. The robot retracts but continues its work tasks with reduced speed and within a safe distance of the human operator. Interaction is achieved through simultaneous work on the same work piece and the warning zones can be initiated and adjusted in a flexible way.

  • 29.
    Augustsson, Svante
    et al.
    University West, Department of Engineering Science, Division of Automation Systems.
    Olsson, Jonas
    University West, Department of Engineering Science, Division of Manufacturing Processes. University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Gustavsson Christiernin, Linn
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Bolmsjö, Gunnar
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    How to Transfer Information Between Collaborating Human Operators and Industrial Robots in an Assembly2014In: Proceedings the NordiCHI 2014: The 8th Nordic Conference on Human-Computer Interaction: Fun, Fast, Foundational, 2014, p. 286-294Conference paper (Refereed)
    Abstract [en]

    Flexible human-robot industrial coproduction will be important in many small and middle-sized companies in the future. One of the major challenges in a flexible robot cell is how to transfer information between the human and the robot with help of existing and safety approved equipment. In this paper a case study will be presented where the first half focus on data transfer to the robot communicating the human's position and movements forcing the robot to respond to the triggers. The second half focuses on how to visualize information about the settings and assembly order to the human. The outcome was successful and flexible, efficient coproduction could be achieved but also a number of new challenges were found.

  • 30.
    Axelsson, Daniel
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Olsson, Daniel
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Utvärdering av olika dynamiska lastmodeller i PSS/E2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor’s thesis has been performed for Vattenfall Eldistribution AB. The purpose of this work has been to create understanding of dynamic load models and clarify how they function and how they can be used. The aim has been to perform simulations on short circuits and motor starts for two different load models. A part of the work is also to describe the basic principles of the induction motor to create a connection between simulation and theory. The theory of the induction motor contains information about the electric induction that is the basic principle of the induction machine. It also contains the correlations between torque, speed, current and voltage and also a description of the equivalent electric circuit. The IMD program is a program connected to PSS/E and it has been used to create the model for the induction motor that has been used for the simulations. The simulations have been based on instructions from the advisor and instructions from the PSS/E manuals. Simulations have been run with two of the built-in load models in PSS/E, one general load model and one model for induction motors. Short circuits have been simulated on both models and motor starts on the induction motor model. Short circuits have been simulated with two different fault durations 0.15 and 0.4 seconds. Motor starts have been simulated with two different transformer sizes 1.5 and 3.0 MVA and three different values of the inertia time constant 0.7, 1.0 and 1.5 MWs/MVA. At short circuit the fault duration causes larger currents and longer recovery times for both load models. At motor start the size of the transformer, in MVA, and the inertia time constant affects the motors starting time. Larger transformer means shorter time because of lesser drop in voltage. A larger inertia time constant means longer time.  If only the size of the voltage drop is of interest and not the course of the event, the motors start admittance can be used instead.

  • 31.
    Baric, Velibor
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Mugisha, Arthur
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Elkvalitetsmätningar vid Högskolan Väst och kartläggning av hur elkvalitetsutredningar hanteras vid elnätbolag2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today voltage quality is important in society, and with the constant continuing development of new modern technological products also makes people more demanding market and its products. This report describes the regulatory requirements on power quality and describe how a power quality works in practice. A clear written guidance on electrical connectivity have been performed in order to get clear instructions on how to connect today's instruments. Measurement has been conducted at University West for 24 hours using the school's equipment and with the help of an experienced supervisor. Furthermore, the report will include what affects the power quality and the consequences that may occur when there is poor power quality in the electricity grid. A distinction has been made on three network companies in Sweden of different size. The three network companies are Vattenfall AB, Göteborg Energi Nät AB and Trollhättan Energi AB. The survey has been done through interviews with officers and electrical engineers. The reason for this limitation is performed to find out if there are any established routines on how network companies handle customer complaints and unsatisfied customers. In addition, the report will describe the differences and similarities how these tree network company handled customer complaints. After interview with electricity suppliers can be concluded that there are few costumer complaints/cases per year from customer to the electricity supplier given how many customers it has. The result for measurement on voltage fluctuations, harmonics and flicker shows accordance with standards accepted values and it can be stated that University West has strong network.

  • 32.
    Barrvik, Erik
    et al.
    University West, Department of Engineering Science, Division of Computer and Electrical Engineering.
    Hagman, Alma
    University West, Department of Engineering Science, Division of Computer and Electrical Engineering.
    Undersökning av orsaker till komponenthaverier i uppsamlingsnätet till vindkraftparkerna Vettåsen och Mårtensklack2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to investigate why the cable terminations and power transformers in Wallenstam’s wind power plants, at Vettåsen and Mårkensklack, have broken down six times since December 2011, which was when they were first put into service.

    Power readings have been taken but there are no records for the times of the failures, which make it difficult to specify the failure source. However, from the readings that have been taken, there is nothing to indicate a cause for the failures. The transients are small and the proportions of harmonics are low. Since the instruments used to take the readings will only record up to 50th harmonics, a possible cause of failure could be high harmonics. Thunder storms, and cutovers in the power grid can probably be dismissed as sources of failure as well as manufacturing and installation faults.

    One proposal to remedy cable termination failures is to use geometric terminations which have been developed for grids with harmonics. Also, to reduce transients in the systems, surge arresters could be installed at the Vettåsen and Mårtensklack stations to ensure that the power quality can be monitored. The power readings need to be continued to specify the failure source

  • 33.
    Benages Montolío, Sergio
    University West, Department of Engineering Science, Division of Automation Systems.
    Robot Behaviour Monitoring in Friction Stir Welding2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Friction Stir Welding is a solid state join process in which the heat need is produced by the friction of a tool on the work pieces. The tool rotates on the surface and also applies a force against it to create the needed friction. This technology does not use any consumable and does not produce any gas, which makes it cost effective, save for the operators and clean.

    The equipment used for this technology has been changing within the years. Milling machines were adapted to it at the beginning. After, specific machines for friction stir welding were developed, providing higher down force and control systems. Nevertheless, the lack of flexibility of machines made industrial robots became an alternative. Robots have limitations in terms of stiffness. But, they can be used to weld complex geometries and they can be used in large scale applications due to their flexibility and low cost.

    This project studies the process from the robot behaviour perspective. The main objective is to achieve a better understanding of the process to contribute to the continuous development of robotic FSW. An acquisition system was developed to monitor different signals from the robot such as, forces, torque, path deviation, and vibrations. The data acquisition system developed and mounted at PTC was tested and its limitations were examined. The developed system has been used for conducting different experiments: The differences between the robot system and a system based on a FSW machine situated at TWI were studied; and, in addition, the behaviour of the robot under different welding parameters was investigated.

  • 34.
    Bennehag, David
    et al.
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Wulcan, Alexander
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Claesson, ommy
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Förstudie till ett stadstäckande och öppet WiFi i Trollhättan2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Förstudien behandlar den tekniska delen av ett teoretiskt stadstäckande öppet WiFi i Trollhättan, Sverige. Trollhättans kommun beställde en förstudie från Högskolan Väst som skulle agera beslutsunderlag till hur de skulle ta ärendet vidare. Studien är begränsad till den tekniska biten, där bland annat val av utrustning, trådlösa tekniker och riskanalys av nätverket ingår. Arbetet varit väldigt teoretiskt inriktat med en metod som till största del består utav att samla information och kunskaper från vetenskapliga rapporter, teknikorienterade hemsidor och andra relaterade arbeten.De trådlösa standarder som jämfördes teoretiskt i förstudien var 802.11g och 802.11n. 802.11n valdes som den standarden som bäst passade just detta nätverk, främst för dess positiva egenskaper när det gäller täckning, hastighet och bakåtkompatibilitet. 802.11n seräven ut att garantera en säker framtid när det gäller implementering i mobila enheter. Föreslaget på utrustning består av två olika accesspunkter, antingen 2602e eller 3602e beroende på den slutgiltiga budgeten. Dessa produkter är från Cisco och klarade olikastresstester med bra resultat samtidigt som de stödde den föreslagna standarden 802.11n. WLAN controllern (Ciscos 5500-serie) som valdes ut stödjer det krav på antal accesspunkter som bestämts, samtidigt som den lämpar sig bra för eventuella framtidakrav. Routern till detta nätverk är en Cisco 891-router. Anledningen till att denna router valdes var för att den har 4 portar som kan ge ström över Ethernet till accesspunkterna. Säkerhetsanalysen gjordes med hjälp utav CORAS-metoden där det diskuteras vilka riskernätverket kan ställas inför och vad dessa risker kan få för konsekvenser. Försök till att hitta lösningar som var direkt applicerbara på det stadstäckande öppna nätverket gjordes även.Förstudien avslutas med en kostnadsberäkning av nätverket, baserad på andras tidigare arbeten och deras kostnader, speciellt från Jönköping, Helsingborg och Mountain View.

  • 35.
    Bennulf, Mattias
    et al.
    University West, Department of Engineering Science, Division of Computer and Electrical Engineering.
    Svedman, Jacob
    University West, Department of Engineering Science, Division of Computer and Electrical Engineering.
    Automatiserat hem: med gränssnitt för anslutning av utrustning2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim is to find out how to develop a system for automated homes, where users can eas-ily connect custom built equipment. An example would be controlling a sprinkler or meas-uring wind speed. It should also be possible to develop more advanced accessories.

    To create a system that meets this, the system must have a central system to coordinate de-vices and data. We also need an open interface for communication between the central and the user devices. One should replace direct change in code and database center to instead create graphical interface to the users, it makes it easier for them to learn the system. One should not, however, restrict user freedom to develop units, more than the functionality of the interface and the center's configuration options. Parts of the requirements was imple-mented in a prototype, to confirm that the system works in reality. The prototype is based on a server with Debian as central in the home. For example, it can take a decision whether the alarm will go off or if a lamp should light. The user should easily be able to give in-structions to the central and reprogram how it should behave. Users can develop their own equipment and then simply connect it to the central and configure it via various web-based tools. In this way, accessories are created and connected without changing anything on the server more than the contents of the database. To test the system we created a modular house that is two walls in a cross, where equipment and central system are placed. Since power and lock bolt where used, this resulted in that some disruption where noticed and removed

  • 36.
    Berg, Gustaf
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Brattlöf, Magnus
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Distributed Checkpointing with Docker Containers in High Performance Computing2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Container-virtualisering har blivit mer och mer använt efter att uppdateringar till cgroups och namespace-funktionerna släpptes i Linuxkärnan. Samtidigt så lider industrins högpresterande beräkningskluster av dyra licenskostnader som skulle kunna hanteras av virtualisering. I den här uppsatsen utformades experiment för att ta reda på om Dockers funktion checkpoint, som fortfarande är under utveckling, skulle kunna utnyttjas i industrins beräkningskluster. Genom att demonstrera detta koncept och dess möjligheter att pausa distribuerade containrar, som kör parallella processer inuti, användes den välkända NAS Parallel Benchmarken (NPB) fördelad över två test-maskiner. Sedan så pausades containrar i olika ordningar och Docker lyckas återuppta benchmarken utan problem både lokalt och distribuerat. Om man försiktigt överväger ordningen som man skriver ner containers till disk (checkpoint) så går det utan problem att återuppta benchmarken lokalt på samma maskin. Slutligen så visar vi även att distribuerade containrar kan återupptas på en annan maskin än där den startade med hög framgång. Dockers prestanda, möjligheter och flexibilitet lämpar sig i framtidens industriella högpresterande kluster där man mycket väl kan köra sina applikationer i containrar istället för att köra dom på det traditionella sättet, direkt på hårdvaran. Genom användning av Docker-containers kan man hantera problemet med dyra licenskostnader och prioriteringar. 

  • 37.
    Berg, Gustaf
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Larsson, Daniel
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    En jämförande studie av tekniker för trådlös platsanalys vid Universeum2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis a comparison between a predictive site survey and two passive site surveys is performed, to see if only a predictive survey is enough to estimate a well-functioning wireless network. Some fundamental facts and techniques that are involved in wireless networks are presented and also the method of how the site surveys were planned and performed. The outcome is compiled in diagrams. The difference between a predictive and a passive site survey is analyzed, and shows if the prediction is trustworthy or needs to be verified.

  • 38.
    Bergkvist, Sofia
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Runge, Johanna
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Allmänna och enskilda vägar: Väghållaransvar utanför detaljplanelagt område2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In terms of traffic, in order for the infrastructure to work it requires that the road network fulfills its function. Communication between the different parties, the Swedish Transport Administration (Trafikverket), municipalities and individual property owners is important, and situations with conflicts and disagreement are easy to evolve. Which part should manage the operation and maintenance to a certain road and what the laws say about each road are sometimes unclear. The Swedish Transport Administration, municipalities and individual property owners are the three different parties that can be responsible for operation and maintenance, also known as road holders, by roads. If the road is located within or outside of the planned area depends on which legislation is applicable. Planning and building act (PBL) and road legislation (VägL) are the laws used inside the planned area, but so is the plant legislation (AL) in the formation of community facilities. It is mainly the planning and building act that is applied because it regulates the planning, the road is then named street according to PBL, but in some cases the municipalities may choose to plan the road according to the road legislation. In cases where the road legislation is applied the process is more extensive and for this law to apply, the roads must be public. Outside planned area there is no law that regulates in the same way as the planning and building act, instead the plant legislation is applied for the individual roads mainly to establish a community facility. It is at the establishment of the community facilities the statutes are set, these regulate the operation and maintenance of the road which concerns the individual property owners. The study includes a survey conducted to 49 municipalities in the county Västra Götaland. Four of these municipalities were then selected for a further interview. The Swedish Transport Administration and National federation individual roads (Riksförbundet enskilda vägar) were also interviewed, this in order to get an overall view and not only information from different municipalities.The result is based primarily on the interviews but also the answers from the survey. The information that emerged from the interviews with the municipalities differs from the answers received from the survey whether the municipalities experience problems with managing individual roads. Instead, the municipalities mean that there are generally more problems in the planned area than outside. The result also indicates a variation between the municipalities, while the Swedish Transport Administration has clear limits on the selection of road holders. REV addresses the problem of the difficulty of getting people to arrange  ii Allmänna och enskilda vägar – Väghållaransvar utanför detaljplanelagt område  the board work on an individual road. The definition of public and individual road differs between the different interviewed parties. The study reflects on distinct guidelines for when a road should be public respectively individual in order to clarify the boundary of when road maintenance takes over and another ends.

  • 39.
    Berndtsson, Jesper
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    By, Mathias
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Analyzing and improving a wireless network2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report is about how a site survey is carried out using software and how a site survey can collect the information needed to improve the existing wireless networks. The report provides both general information about wireless networks and practical examples with authentic measurements in the corporate environment.

    Problems can arise in a wireless network if the planning is not properly done. A measurement have been made in second floor, where company X is located.

    The results of the survey is presented in images that show the strength of Company X wireless networks, on the second floor. Images also shows noise, overlapping channels and how the signal strength related to these.

  • 40.
    Berndtsson, Jesper
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    By, Mathias
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Analyzing and improving a wireless network2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report is about how a site survey is carried out using software and how a site survey can collect the information needed to improve the existing wireless networks. The report provides both general information about wireless networks and practical examples with authentic measurements in the corporate environment.

    Problems can arise in a wireless network if the planning is not properly done. A measurement have been made in second floor, where company X is located.

    The results of the survey is presented in images that show the strength of Company X wireless networks, on the second floor. Images also shows noise, overlapping channels and how the signal strength related to these.

  • 41.
    Beyrouti, Magdalena
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Larsson, Patrik
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Beredning av landsbygdsnät Restenäs-Andorra i Uddevalla kommun2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is about how preparation work is accomplished by contracts and permit search to network planning and dimensions. The requirement for reliable electric power increases because electricity is such an important part of our society. Large disruptions cause significant costs for electric distribution companies and customers. . To increase reliability and make the power grid weather secured, overhead lines are replaced with underground power cable.

    The preparation work is preformed to weatherproof the electric power grid in Restenäs-Andorra outside Ljungskile in the municipality of Uddevalla, by placing power cable in the ground instead of overhead power lines. The project will be implemented in connection with the development of communal water and sewer to reduce the cost of excavation.

    The result of this preparation work includes a new 10/0,4 kV substation, four cable boxes together with 1200 m of high voltage power cable and 800 m of low voltage power cable. The electric transmission network has been placed in the same excavation as water and sewer as long as possible. The substation and cable boxes are placed for easy access and to create a good mesh. A P2-calculation has been created to get an overview of the costs of the project.

  • 42.
    Beyrouti, Samer
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Yaghoubipoor, Mohammad
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Standardisering av reläskåp för transformatorstationer2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The thesis is a case study about standardization of a relay cabinet at E.ON´s 55/11 kV substation. Standardization of the relay cabinet implies that a solution is developed from a station and applied to other stations with the same conditions. Prior to the development of the relay cabinet, a basic theoretical study was performed about the external and internal faults that a transformer may be exposed to and the most common transformer protection philosophies were investigated. In addition to relays other components in the relay cabinet were also examined. The project was then divided into parts where control of the assigned data and circuit diagrams were performed. The material consists mainly of connection charts and circuit diagrams that describe the station and cabinet construction and the components used at present. The charts for the existing devices in the relay cabinet were examined extensively. In combination with E.ON's requirement for the cabinet components and the transformer station the components technical specifications as well as the protection functions were established. A request for quotation was sent to the leading manufacturers with the component's technical specifications. The answers provided by the suppliers were analyzed and then compared with the existing ones. A request was also sent to relay cabinet installation companies. Only one company was able to perform the work. All data was then compiled and analyzed. Following the study of the market leading manufacturers relay D, voltage regulator F and annunciation relay H were chosen as the best recommended components. Other products that have some advantages are analyzed and discussed in the report. The only installation company that responded was chosen to perform the installation work.

  • 43.
    Birgersson, Patrik
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Svensson, Martin
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Utvärdering av möjligheter för semiautomatisk reläskyddsprovning med Omicron CMC 3562017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When energy companies undertake the maintenance responsibility for their power plants and facilities the protection systems may be tested by different contractors. As a result, the testing procedures may differ between facilities. In order to achieve a more similar testing of the protection relays they should be tested the same way every time. Testing of relays are usually performed by experienced personnel that may employ in slightly different ways of testing due to the lack of one which is standardized. This leads to a situation where the knowledge within this area of work stays in the minds of only a few employees of the company.

    The reason for this project to be made is the employers wishes to investigate if the testing of relays can be performed in a more similar way in order to achieve comparable results and to minimize the risk of mistakes made during the testing.

    With Omicron CMC 356 and the associated software "Test Universe 3.10" it is possible to program tests in advance and bring to the station and implement the prepared tests. This report is performed as a pilot project to show the client how the tests can be programmed and how Omicron might be implemented in the maintenance testing of their relay protection.

    The report begins with a theoretical review of the functions that the thesis comprises. The construction of the relay with the principles it uses are explored, the limits and accuracy for the measurements are also reviewed. The thesis is because of time constraints limited to testing the functions: overcurrent, overvoltage, undervoltage, underimpedance, as well as differential and frequency protection. The thesis also contains a practical part in which testing of the relays was completed in a hydropower plant. Omicron CMC356 was the testing equipment used along with the related software "Test Universe 3.10", where the testing functions were programmed. The modules used for testing the relay functions are described along with the essential parts needed to test the functions that the thesis comprises.

    The conclusion of the thesis is that several of the functions needed can be performed automatically. A decision has to be made about the balance between economy and quality because of the initial work that have to be made to program every station that is meant to be tested in this way.

  • 44.
    Bodestål, Emil
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Jakobsson, Daiel
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Metoder för att minska risken för sympati-utlösning av Vattenfalls transformatorstationer2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This Bachelor's Thesis has been produced in cooperation with Vattenfall Eldistribution AB. In the center of operations in Trollhättan, they manage their electric grid in Sweden. During the energizing process of a transformer in parallel with another one in use, the station sometimes becomes disconnected. This phenomenon is called "sympathetic disconnection". It occurs in some way randomly and is fairly uncommon. At Vattenfall it occurs a couple of times every year. This means that there are few cases to study and therefore most of the project is based upon interviews and one well-documented case. Based on that case, a computer model was created in PSCAD EMTDC and modified to create a situation where the phenomenon always occurs.

    The goal for this project was to find some strategies and test those in PSCAD to see if they would make the situation better. The different types of strategies tested are to change the point of circuit-breaker operation, the tap changer, an alternative energizing from the secondary side, different winding connections and the significance of a strong network. A theoretical analysis of the importance of an inrush limiting resistor and synchronized switching was also made.

    The results show that the time of the circuit-breaker operation is of great importance. With support of synchronized switching an energizing can be done completely without affecting the feeding grid, nor the parallel transformer. Individual breakers seems to be worse than just sensing the voltage zero crossing and operating all the breakers simultaneously. The simulations have shown that some measures can improve the chances of a successful energizing. The tap-changer should be set in the position with the largest ratio. A wye-delta connected transformer is better than a wye-wye connected, which is the standard at Vattenfall. It is also standard to energize transformers from the primary side. Simulations have shown that an energizing from the secondary side would result in several benefits. At last, a strong network is preferred.

    The earth-fault protection relay in the feeding line is most prone to cause a disconnection. Therefore, depending on the situation, a change in the time setting in the relay's fourth step should be considered.

  • 45.
    Bolander, Ola
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Erving, Ivar
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Elkvalitetsundersökning vid Sahlgrenska sjukhuset2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    On behalf of ÅF Consult an electrical power analysis has been made for Västfastigheter at a switchgear at Sahlgrenska University hospital in Gothenburg. The intention is primarily to investigate the data of most interest to the customer such as variations in voltage, imbalance in supply voltage, voltage harmonics, power consumption and neutral conductor current. In addition, Västfastigheter have requested an investigation of a vibrating busbar trunking supplied from the switchgear. The starting point of thesis work is a theoretical background described in the first part of the work and the goal is to deliver a good basic understanding of the concept of power quality.

    Measurements have been carried out both when the system was fed from the normal supply as well as during a 6 hours long test of the backup power supply system. The result at normal supply showed, according to current regulations, that all parameters are approved except for harmonics number 9 and 15 for which to high levels are detected. When the load was fed from the backup power supply the results show no significant changes compared when the load was fed from the normal power supply. However, some noticeable phenomena linked to the voltage and the current waveforms are noted. They are of interest for getting a deeper understanding of the different supply modes. In backup supply mode the grid impedance increases, this is normally described as the grid becoming weaker. This is shown as increased imbalance between the voltage levels of the three phases. It is also characterized as the current distortion having a greater impact on the waveform of the voltage leading to a larger level of voltage distortion compared to normal supply.

    The connected load on the vibrating busbar trunking is examined with a power quality analyzer and vibrations are measured by an accelerometer. Since the degree of the vibration decreases as the electrical power is unloaded throughout the different levels at Sahlgrenska, the theory is that they are related to the level of the current. To further strengthen this theory reference can be made to two adjacent busbar trunking of the same type that are considerably less loaded. They have noticeable vibrations but with a much lower magnitude, which is comparable with how the investigated vibrating busbar trunking behaves further out.

  • 46.
    Bolmsjö, Gunnar
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Reconfigurable and Flexible Industrial Robot Systems2014In: Advances in Robotics & Automation, ISSN 2168-9695, Vol. 3, p. 117-Article, review/survey (Other academic)
    Abstract [en]

    This paper presents a concept for reconfigurable and flexible robot systems. To reach a technology readiness level where solutions and results can be implemented in industry, the focus in this work is on systems with limited number of robots, and work scenarios which are reasonable complex but hard to automate using standard solutions.Four distinct areas have been identified as important within the concept and further studies: (i) human machine interaction, (ii) safety including collaboration, (iii) programming and deployment, and (iv) planning and scheduling. Feasibility studies have been made which addressed issues (ii) and (iii), in scenarios with collaboration between robot and human, or between two robots. For the chosen work scenario, manufacturing of structures in wood for family houses, challenges related to programming and safety was identified and possible solutions outlined.The concept and the studies indicate that feasible solutions can be found and designed given a reasonable consistent work processes and products. In this study, the processes are similar, nailing and screwing but different sizes may apply, the material is similar but variations may apply, and the construction is different of each product, but include the same type of operations at different locations. Our study confirm that human collaboration improves the ability to implement and use robots as it make it possible to move some operations to the human which otherwise would add to the complexity of the system. Furthermore, programming can also I general be simplified although methods for automatic programming has been tried out. But in some cases, the solution space is limited and the ability to move certain operations to a human simplifies the programming task. However, further work needs to be done in this area specifically related to safety issues for safe collaboration.

  • 47.
    Bolmsjö, Gunnar
    et al.
    University West, Department of Engineering Science, Division of Automation and Computer Engineering.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Svensson, Bo
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Collaborative Robots to Support Flexible Operation in a Manufacturing System2012In: Flexible Automation and Intelligent Manufacturing, FAIM 2012 / [ed] Hasse Nylund, Satu Kantti, Ville Toivonen, Seppo Torvinen, Tampere University, Finland, 2012, p. 531-538Conference paper (Refereed)
    Abstract [en]

    Collaborative robotic systems where human(s) and robot(s) cooperate in performing a common task is an attractive solution to introduce automation combined with high flexibility for tasks that have a high complexity and characterized by low volume or down to one-off. By introducing collaboration in robotics systems, the operator can complement with cognitive capacity and skill in order to gain in flexibility and agility in the task operation. This paper describes on-going work related to work on collaboration between operator and robot. User scenarios are outlined together with methods, software components and hardware to support collaboration, where some of these are under development. As the standards related to collaborative robotic systems are soon to be completed, it is expected that this type of semi-automatic systems will be important for flexible and agile automation of production which otherwise cannot be automated.

  • 48.
    Bonilla Hernández, Ana Esther
    et al.
    University West, Department of Engineering Science, Research Enviroment Production Technology West.
    Beno, Tomas
    University West, Department of Engineering Science, Division of Production Engineering.
    Repo, Jari
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Wretland, Anders
    GKN Aerospace Engine Systems AB, Trollhättan, Sweden.
    Analysis of Tool Utilization from Material Removal Rate Perspective2015In: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 29, p. 109-113Article in journal (Refereed)
    Abstract [en]

    An end of life strategy algorithm has been used to study a CNC program to evaluate how the cutting inserts are used in terms of their full utilization. Utilized tool life (UTL) and remaining tool life (RTL) were used to evaluate if the insert has been used to its limits of expected tool life, or contributing to an accumulated tool waste. It is demonstrated that possible means to improvement exists to increase the material removal rate (MRR), thereby using the insert until its remaining tool life is as close to zero as possible. It was frequently found that inserts were used well below their maximum performance with respect to cutting velocity.

  • 49.
    Bradley, Jonatan
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Höglind, Fredrik
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Anti-Virus resursutnyttjande2016Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    How does Anti-Virus software affect the computer performance? Avast, Windows defender, Eset Nod32 and Symantec are a few of the big Anti-Virus companies that specialize in protecting your computer by removing virus, malware and trojans. Four Anti-Virus software and three scenarios was chosen to test cpu, memory, networks effect of the Anti-Virus software. Every scenario were tested three times ten minutes for every Anti-Virus software. Five minutes composed of a baseline and no test performed, after five minutes we conducted the test. Results differentiated between the different scenarios. Altogether, the Anti-Virus software differentiated minimal between each other. The data showed that the free Anti-Virus software was every bit as good as the paid Symantec version in utilizing the computer resources.

  • 50.
    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.

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