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  • 251.
    Nilsson, Hannes
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Konstant landanslutning för linfärjor2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor´s thesis has been carried out on behalf of Callenberg Technology Group. The thesis is a preliminary study and shall be used during the change from diesel to constant shore connected for cable operated ferries. A survey on three different distances, 910 m, 650 m and 300 m has been presented in the thesis. The solutions shall be reliable and cost effective.

    Ferries have, during the recent years, been converted from diesel power to modern fossil free solutions. Cable operated ferries is not an exception. The main solution that STA road ferries has been using is constant shore connection. The connection provides enough electricity to operate the ferry. The cable is rolled in and out using a motorized cable reel placed on the ferry. When 300 m or longer distances is used problem accrue, such as, voltage drop and mechanical tensions on the cable. The focus during this bachelor´s thesis has been to focus the studies on the electrical problems.

    To decide if constant shore connection could be used on this application, calculations and a dialogue with various cable reel companies have been carried out. When the transmission voltage for the distances, 300 m and 650 m, should be decided, different voltages have been compared but with the given circumstances 1000 V is best fit for this area of use. It is also the cheapest solution, according to the calculations and estimations made in this thesis. The reel for the 650 m crossing has an outside diameter of 7000 mm and the reel for the 300 m crossing has an outside diameter of 4200 mm.

    According to the calculation and the solution presented in this thesis it is not possible to use a constant shore connected cable ferry with a crossing distance of 910 m. For a cable reel to be used to 910 m crossing distance, different components or another solution needs to be presented. During this thesis it has been concluded that the mechanical tension is a bigger problem than the electrical problems that occur. Mechanical tension is therefore the reason why constant shore connection cannot be used for all cable operated ferry.

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  • 252.
    Nilsson, Martin
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Projektering av elanslutning av nytt bostadsområde i Rävlanda2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis deals with the pre-design of a new development area for six apartment buildings, two technology buildings and a pump station located in Rävlanda, Härryda municipality. The projection is done on behalf of the network owner Vattenfall Eldistribution AB.

    The service connections for the new area consists of six 125 A electricity subscriptions, two 160A electricity subscriptions and one smaller 25 A electricity subscription. The design will include both 0.4 kV and 12 kV distribution networks. The area's electrical connections are entirely designed, including the dimensioning of a new transformer station and the high and low-voltage supply system.

    The work consist of a comparison of two different solution proposals on how the grid can be designed. The comparison include price, electricity quality and capacity for future power needs.

    The solution proposal that is advocated is solution proposal 2 containing: Holtab N12/3 substation, a 800 kVA transformer, a SDC 440 cable cabinet, 150 m high-voltage cable and 640 m low-voltage cable.

    The total project cost for the solution is 0,66 MSEK.

  • 253.
    Nilsson, Per
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Konstruktion av lyfthjälpmedel till hydraulcylinder2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Among other products, JOAB Försäljnings AB manufactures hook lifts for trucks. The hook lifts are equipped with two hydraulic cylinders. These are lifted into place using round slings and chain hoists. This is not the optimal way of doing it. The reason for this is that the round sling can be incorrectly applied to the cylinder. In a worst-case scenario, the cylinder can be dropped with personal injuries and material damages as a result. The round sling may also cause damage to the cylinder paint through contact which is not desirable.  Thus, the goal of this project is to construct a lifting aid which lifts the cylinder into place in a safe way without damaging their paint. It must also meet Swedish work environment authority (Arbetsmiljöverkets) requirement for CE-marking.  To ensure that the workers will perceive it as helpful in their work, interviews and observations were done to identify their functional demands.  All demands are compiled and the concepts that meet them in various way are sketched. The best suited concept to proceed with was chosen by means of different concept selection methods. At this stage, the workers were also invited to ensure that the right concept was chosen.   Based on the chosen concept, a 3d model was developed. Relevant forces acting on the structure were identified and used in the strength calculations performed. The model was modified until a suitable balance between dimensions, material and strength was achieved. The final result is a lifting aid that will solve JOAB’s assembly problems.

  • 254.
    Nyqvist, William
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Safar, Petrus
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Kartläggning av inkommande gods för en effektiv bemanning2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The study was performed by William Nyqvist and Petrus Safar. The purpose of the study was to map CDC's incoming goods and the information flow between the various departments. The aim was to find relevant parameters that could give the goods receipt manager the right conditions for planning the staffing effectively.

    The theory in the study was obtained from relevant literature books from the library. There were parallels between the theory and what was observed at Volvo and it turned out that the theory was in line with the observation at Volvo.

    During the study, observations and qualitative open interviews were carried out at various departments to get a nuanced picture of the process. Four departments were observed. These departments were: purchase planning, inbound, stansen and goods receipt. The results of the observations and the interviews were used as a basis for the current situation analysis.

    Using the collected information, a survey and four parameters could be determined. Based on these, solutions could be developed to answer the purpose and objectives of the study.

    In the discussion, theory and observations could be linked. The survey showed that there were four parameters that were crucial for the goods receipt manager to be able to plan his staffing. These four parameters are "inadequate communication between the departments","inadequate information", "inadequate documentation program" and "carrier time precision".

    The survey was done using data from the "lastbärarlistan". The charts that were established shows a current situation of incoming goods to the CDC. The information from the"lastbärarlistan" was vague and sometimes even incorrect. An implementation of the AnkRed program was initiated, which will give the staff better conditions for both reporting of trucks and for future follow-ups. A change in the slotplanning was also begun to facilitate the staffing and the flow equalization for the goods receipt manager.

  • 255.
    Olausson, Eddie
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Rohlsson, Joel
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Förbättrad arbetsmiljö ger effektivare virkesförflyttning2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To create value for the customer and to have a continued competitive opportunity towards other companies within the same area of expertise, it is important to be able to review their business processes and take measures where flaws are seen. Elimination of waste is one of the most important things when it comes to streamlining the production process. Derome in Tanumshede has identified that a bottleneck will arise in their roof truss assembly which will lead to longer lead times. The purpose of this thesis is to find suitable improvement proposals that eliminate the bottleneck in the roof truss assembly.

    The aim of the study is to investigate the coming bottleneck and develop concepts that may be relevant to streamline the time it takes to move the wood from the timber trolley to the puck table, while at the same time improving the ergonomics for the operators and preventing the risk of load injuries. The solutions that have been developed have gone through a concept generation where the authors in collaboration with the company produced several proposals which were then taken on to concept management to finally be weighed against each other in a concept selection matrix.

    The report has used the DMAIC model, the method contains five steps that aim to gain an understanding of the project by first defining the problem, conducting relevant measurements, analysing the collected data, and after that improvement proposals are made. The last step in the model has not been implemented as the implementation of the concepts was not included in this study. To collect data for the project, interviews were conducted with the production technician and the workshop manager, a survey with operators, time measurement of the process and measurement of the number of lifts during roof truss assembly. After analysing the data, improvement proposals were developed with the help of concept generation, concept screening, and concept selection matrix. A theoretical framework and a description of the current situation have been produced.

    The concept was developed according to the requirements and criteria that Derome described in the assignment. The potential improvement proposals that were taken further were, developed batch packing, modified timber wagon, adjustable pucks, and a layout change. The recommended proposal ultimately ended up combining batch packing with a modified timber wagon, which is assumed to reduce the transfer time by 30-40%, fewer lifts and is estimated to cost 10% of the budget.

    At the end of this report, recommendations are given for future work by making a layout change, which requires a greater operational effort and a higher budget.

  • 256.
    Oliveros Ordás, Alejandro
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Automated handling of Perkadox bags2020Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Automating an industrial process is a complicated task since it is necessary to obtain very few defects. In order to do this, it is necessary to be able to analyse each of the products involved in order to know how to deal with them correctly. Borealis, a provider of innovative solutions in the fields of polyolefins, base chemicals and fertilizers, aims to automate a process in which a substance, Perkadox, harmful to health is used. To accomplish this, three solutions will be proposed in this thesis.

    The process consists of picking up and moving a box with an industrial robot, then opening the box for picking up and leaving in the conveyor Perkadox plastic bags using the same robot. Finally, these bags have to be opened to get their contents.

    ABB's RobotStudio software is used for doing the simulation and programming offline.

  • 257.
    Olsson, Niklas
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Selberg, Christian
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Numerical simulation and experimental validation of a manufactured wing profile2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The background for this thesis originates from a study of the flow characteristics for an airfoil of the type NACA0018. The aim for this thesis was to evaluate how the characteristics of the flow over the NACA0018 profile depend on surface roughness. Airfoils were manufactured in Aluminum by Computer Numerical Control-milling and in polylactide polymer using a 3D-printer, where some of the profile surfaces were postprocessed with sandpaper in various grain sizes. The surface roughness of the profiles was evaluated in a 3D optical profilometer using white light interferometry from Filmetrics. By that technique 3D surface plots were created. The manufactured airfoils were tested in a wind tunnel where the achieved data was made dimensionless for comparative purposes. The computational fluid dynamics simulations were performed in Ansys Fluent and compared against the wind tunnel data as well as with the data from a previously made study at htw saar. The results from the wind tunnel tests show that the surface roughness has an effect on the flow characteristic of the airfoil, where different angles of stall were observed in the comparison. The difference for the dimensionless numbers coefficient of lift and drag show that the manufactured aluminum airfoil performs better compared to the 3D-Printed airfoil in this study. It has a higher performance mean value for both of these coefficients in a span of angles between 0 and 30 degrees. When compared, the results from the simulations and wind tunnel experiments do match in some cases, where the dimensionless coefficients and stall angle coheres. Further studies based on this report are recommended, where small geometric changes to the profile could be tested and validated.

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  • 258.
    Onyeji, Harrison
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Physical Simulation of heat affected zoneof Aluminium butt weld2020Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The demand for better and more efficient metallurgical processes that will guarantee quality product at low cost, stimulates intensive research to reach these goals. In this respect, any full-scale industrial experiments are not cost effective due to material and time wastage, but physical simulation does. The application of Gleeble System in Physical simulation research has found broad application in nearly all spheres of metal processing industries. These applications include process optimization, material characterization, etc. Physical simulation unlike computer simulation being very close if not the same to the real-world process. It can beused to reproduce on laboratory scale the same process that happened in the real industrial processing conditions. In this work physical simulation of heat-affected zone (HAZ) of aluminium butt weld of AW6005-T6 extruded wrought aluminium was characterized through series of experiments.The base material (BM) was welded using standard metal inert gas (MIG) pulse welding process. The following welding parameters were set in the welding machine for the welding experiment, current = 120 A, wire feed speed = 5.3 m/min, voltage = 19.25 V, weldingspeed = 10 mm/s. The actual weld thermal cycle was recorded with the help of thermocouples (TC) attached to the plate. This weld thermal cycle was used as an input in the Gleeblefor physical simulation of the BM. In the Gleeble experiment, the BM was subjected to three different peak temperatures 350 °C, 450 °C, and 550 °C for heat treatment purposes during which the temperature distribution was measured and evaluated. At room temperature, the three peak temperature heat-treated samples were subjected to tensile test using the Gleeble testing machine.The weld, heat treated, and temperature distribution samples were metallographically prepared for microstructural analysis which after hardness test was carried out on these sample.The respective resultant HAZ of the various sample was analysed. Optical microscopy (OM)was used to evaluate their Microstructure. Characterization of the HAZ was successfully achieved for the proposed base materials. The weld samples were observed to have HAZ stretch beyond 18 mm from the weld centre line (WCL) which could be attributed to high heat conductivity of the aluminium and the weld parameters used. The HAZ exhibit low material properties relative to the BM. The physical simulated samples reproduced these trends as in the weld samples successfully as observed from the analysis.

  • 259.
    Oresten, Cecilia
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Mir, Tara
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Building loss: en metod för effektivare resursanvändning och minskad klimatpåverkan2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Several recent studies show that 30-40% of climate impact on a global level is from the real estate industry. According to IVA there is a risk of that number rising to 50% by 2050. In 1993 John Gray developed a method to calculate how much of the floor area in an office space that is actually occupiable. The purpose of the studiy is to develop Grays method so that it includes area efficiency, climate impact and costs (we call this addition Area, Cost, Environment, ACE). The method is relatively unknown in Sweden and, therefore, the second purpose of the study is to raise awareness of the Building Loss method and concept.

    The new method is developed from a study case, office space Svea. Svea is chosen to represent the most common type of office in Sweden. Grays method is also translated to Swedish and thoroughly explained. The climate impact is calculated from average values of district heating regarding carbon dioxide, nitric oxide, sulfur dioxide, dust and particle emissions

    The cost for Svea is calculated for operation and maintenance during one year. The costs are based on Repab Fakta books that publishes updated key figures for operation and maintenance in office spaces every year.

    Two interviews have been held with people who have great knowledge in the real estate industry and is considered to benefit from a method like in this study. The interviews gave answers to what need they thought existed for a method like this.

    The study's results have been analyzed and discussed from different points of view. The result shows that there is a lack of knowledge about Building loss today in Sweden. The large consequences that Building loss results in demonstrate that there is an unspoken need for this type of method in Sweden. Furthermore, it has been established that Sweden may need to introduce Building loss as a standard like ASTM in Canada and the USA for the previously mentioned reasons, but also to prolong the service life of a building.

  • 260.
    Ossiansson, Mattias
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Designat utomhusskydd för luftvärmepump2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report describes the development of a designed shelter for an air heat pump. The shelter consists of two consoles in powder lacquered steel with four panels in eight millimeters thick compact laminate plates screwed in place. The protection is intended to be used for airsource heat pumps installed and mounted on house walls. This is a project that has been commissioned by the interior design company Amal House Productions in Åmål, which had planned to manufacture and sell the product. The product development includes determination of design and construction, suitable manufacturing and assembly methods and a risk analysis with FMECA. To determine these criteria, flow simulations and structural strength calculations were made to ensure that the design was suitable for the purpose. The flow simulations were made in the program COMSOL Multiphysics where also FEM calculations were done with load cases. The calculations were done with both snow and wind loads using FEM- and hand calculations. A design study was carried out with various design proposals were presented to several people who gave their opinion on the different design ideas. The development of this product never came to the stage of manufacturing since time could not be given because it was a busy time for the company. This report will therefore only describe the development of a theoretical product concept. The major part of this project was to investigate how air flows are affected by a shelter for an air heat pump. As the designer lacked experience in this field, this work with the study of air flows took most of the total project time. More time was needed to investigate manufacturing methods in more detail and how the design can affect the time of manufacturing. The designer had also wanted to perform practical experimental tests on airflows and sound measurements for a continued study if the product were to go towards production. Even a further design study was needed regarding the design of the air openings. The product is considered by the designer as safe and could be manufactured and used as protection for a real air heat pump. However, it is uncertain how the manufacturing costs look and whether the design is considered attractive, which means that development work may need to be continued.

  • 261.
    Ottosson, Hans
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Utveckling av miljövänligt elverk för personligt bruk2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Möjligheten att utveckla ett vattenkraftverk för personligt bruk har behandlats. Målet var att se om det gick att tillverka ett kraftverk som kan underhålla en avlägsen stuga med ström för att använda TV, dator, lampa och dylikt när den konventionella elen inte finns installerad. Ett koncept utvecklades med syfte att minimera miljöpåverkan. Detta koncept byggdes och begagnade delar användes vid tillverkningen. Anläggningen kunde också testas, vilket visade att tillfredställande resultat erhölls.

  • 262.
    Ouallou, Simo
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Yakob, Steven
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Undersökning av möjligheter att förse en kundparkering med laddstationer för elbilar2021Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To achieve the climate goal and reduce carbon dioxide emissions, electrification of transport and sales of rechargeable vehicles has increased rapidly in recent years. To meet the development, an available charging infrastructure must be prepared. The report examines the principles for installing public charging stations at a supermarket and provides suggestions for charging stations that can be used. 19 Semi-fast chargers with double sockets and an output of 22 kW are placed together with four quick chargers with double sockets and 50 kW power in a car park belonging to the Bäckebol’s shopping center on Hisingen in Gothenburg.

    The installation is dimensioned for both the maximum power (alternative 1) which is calculated at 1236 kW and also for a reduced power with the help of load balancing (alternative 2) which is combined to 741 kW. Load balancing is used for various reasons but mainly to protect the system from congestion and minimize costs for network connection by reducing the need for security. High and low voltage cables made of PEX insulation and aluminum conductor, dimensioned with associated fuses, and checked with regards to load capacity and tripping condition based on suitable standards. The power station is placed as close to charging stations as possible to avoid high costs during excavation and cable laying. The station contains a transformer whose size varies depending on the power it needs to be dimensioned for.

    The cost of the investment is presented for both alternatives and includes both the charging stations and the electricity grid. Alternative 1 has a total investment cost of SEK 3 million and a repayment period of 6.6 years. For alternative 2 with a total basic investment of SEK 2.3 million, the repayment period will be 5 years. The costs are reported with regards to the investment support from the Swedish Environmental Protection Agency, which is limited to SEK 15,000/Charging point. Revenue may vary depending on the number of visitors while costs may include other services such as billing and maintenance.

    The study is based on various assumptions and according to the authors, the project should be performed with load balancing to reduce costs for the investment and to protect the plant against overload. A profitable and efficient charging solution for customers requires an overall analysis of the customer flow in the shopping center as well as an evaluation of various suppliers inthe market

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  • 263.
    Pakan, Pedram
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Todorovac, Armin
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Kartläggning av metoder och standarder för kvalitetssäkring av virtuell CAD-konstruktion2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis aims to map and analyze current working methodology for updating supporting method documents in 3D modeling at Volvo Cars. Based on a theory that encompasses standardized working methods, a qualitative study has been conducted to identify current work processes regarding handling, tracking and synchronization of data within the Mechanical Engineering & Tooling department. The data collection for this document study of work processes was conducted using four qualitative interviews by members of Mechanical Engineering & Tooling. The analysis of the interview material has resulted in four development areas, experience-based working method, lack of systematic working method, no designated work roles and connection between Volvo Methods are not systematized. The analysis has also shown that the problems are based on poor maintenance and the lack of tracking and synchronization tools. The work has resulted in five improvement proposals that include proposals for possible database systems, standardized working methods and short-term and long-term measures to ensure quality-assured Volvo methods. The suggestions and recommendations made during the work are based on the survey of current working methods and interviews with ME&T and are presented at the end of the degree project. Finally, the results are discussed based on the Covid-19 pandemic and its impact on the project.

  • 264.
    Papadonikolaki, Eleni
    et al.
    Bartlett School of Sustainable Construction, University College London, London (GBR).
    Tezel, Algan
    Department of Civil Engineering, School of Infrastructure and Sustainable Engineering, Aston University, Birmingham (GBR).
    Yitmen, Ibrahim
    Department of Construction Engineering and Lighting Science, School of Engineering, Jönköping University, Jönköping (SWE).
    Hilletofth, Per
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering. Department of Industrial Engineering and Management, University of Gävle, Gävle, (SWE).
    Blockchain innovation ecosystems orchestration in construction2023In: Industrial management & data systems, ISSN 0263-5577, E-ISSN 1758-5783, Vol. 123, no 2, p. 672-694Article in journal (Refereed)
    Abstract [en]

    Purpose

    Rapid advancements in blockchain technology transform various sectors, attracting the attention of industrialists, practitioners, policymakers and academics, and profoundly affect construction businesses through smart contracts and crypto-economics. This paper explores the blockchain innovation ecosystem in construction.

    Design/methodology/approach

    Through a qualitative study of 23 diverse interviewees, the study explores how open or closed the blockchain innovation ecosystem in construction is and who its emerging orchestrators are.

    Findings

    The data showed that construction aims towards an open innovation blockchain ecosystem, although there are elements of hybridisation and closedness, each system pointing out to different orchestrators.Practical implicationsThe study has implications for governments and large companies in construction, showing that open innovation initiatives need to be encouraged by policymakers through rules, regulations and government-sponsored demonstrator projects.

    Social implications

    The data showed that there is lack of readiness for business model change to support open innovation blockchain ecosystems in construction.

    Originality/value

    This is the first study applying the open innovation theory in the construction industry and sheds light into the phenomenon of blockchain, suggesting routes for further democratisation of the technology for policymakers and practitioners.

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  • 265.
    Pekowska, Carina
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Utmaningar och arbetsmetoder för beredning av elnä2020Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis analyses various challenges, routines and working methods with the preparation work of power grids on distribution level up to 24 kV. To describe how planner work and which routines and working methods that exist today, interviews have been held with professionals in the area.Experiences based on my own preparation of electricity grids and my time as project manager for other preparations of electricity grid is shared in this thes.

    Preparing a preparation of a grid involves expertise in many areas such as production technology, electricity calculations, laws and permits, construction work, nature care and a high level of social competence, since the planner establishes many contacts with landowners and authorities. By describing the workflow of a preparation, it is possible to take a closer look at what conditions the planner require and which elements thar are challenging and why.

    The thesis shows that the planner's work routines, technology solutions and choice of cable route are not governed by what the electrical designer considers to be the best solution instead several other factors will have more impact. One factor is that the lead time for the permits of the authorities is so long that the planner does tries to bypass the authority. If it is not possible to avoid a bypass, the planner chooses to send in a solution at the beginning of the preparation with hasty cable rutes and substations placements. Therefore, there is a risk that the first solution may not be the best solution.Another factor is for whom the planner should perform the task. Either it is directly for the power grid owner and the planner then works for a consulting firm or the planner works for a contracting company that deals with both the preparation and the electric construction. The interviews show that consultants are more pressured to produce cheap solutions for the grid owner while the planner who works for the provider is pressed by the constructeurs to get good technical solutions but also that the solutions should have high profit..

    The thesis also presents a number of proposals regarding modernization and streamlining of the preparation process through increased uniformity of the network owners in what a preparation should look like and what it should contain. By ensuring reliable preparation tools and processing platforms within the processing companies as well as an increase incompetence by training and inclusion of the processor in project context.

  • 266.
    Pettersen, Ann Catrin
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Utlösningsvillkor på gatubelysningsnät2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor's thesis has been performed at Trollhättan Energi Elnät AB with an assignment by Trollhättans Stad. The city Trollhättan owns a street lighting grid with approximately 500 km cables and 12 000 lighting points. The fault clearance is important for the safety of the personal and also a requirement from the rules for electrical installations. During a previous project when documentation was updated and short-circuit calculations performed it was discovered that a sufficient fault clearance was not fulfilled for all areas studied. Based on this the idea of this project arose. The purpose of this project is to produce a solution to manage the fault clearing of selected areas and also to compare calculations performed with measurements.

    Bergkrönet, Blåvingen, Guldvingen, Skoftebytorg, Sågkvarnen, Nybergskulla and Stallbacka are stations which have been investigated and solutions for these stations have been presented in this project. All stations are different and therefore investigated one by one to find a good solution based on economic and personal safety perspective. The problems with too long time for fault clearance could be solved by sectioning, new cables, redistribution of the load on the phases and also adding additional fuses. In station Blåvingen the cost of the proposed work was calculated to approximately 12 000 SEK.

    In the Stallbacka area the plan is to replace all the existing light luminaires to LED lighting. The rated power of the luminaries are 50, 100 and 150 W respectively with a total installed power of 30.6 kW. This corresponds to an energy consumption of 134 MWh/year. In this project a change to Lumistreet LED luminaires with a rated power of 32 and 64 W respectively is presented. The total energy consumption is then estimated to 42 MWh/year which gives an energy saving of 92 MWh/year.

    During this project, measurements of fault impedance and earth fault current have been performed both in the end and the beginning of the electrical installation. According to SS 436 40 00 the measured impedances need to be adjusted with a factor of 1.5 due to the temperature increase in the conductor. It was found that the difference between the calculated and the measured impedances increased the further out in the electrical installation it came. An explanation to this is that each streetlight post contributes with a circuit which is in parallel with the return conductor through an interconnection with the PEN-conductor, and this results in a lower impedance.

  • 267.
    Pratt, Justin
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Automated detection of defects on cold deformed metal plates using Thermography and automated classification of images: case studies2020Independent thesis Basic level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 268.
    Pérez Blas, Jaime
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Build rate Optimization of LPBF Alloy 718: Taking into consideration the defect density and morphology2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Over the years the industry has been tried to optimize processes in order to save money, time and improve several ratios. In the last years, Additive Manufacturing (AM) has raised its popularity because it allows to build parts faster and in a more autonomous way than conventional methods. Moreover, with this technique it is possible to build complex structures and optimize the whole process while maintaining good mechanical properties.

    LPBF is an important technique that is used in the AM industry and specifically in this thesis this technique coupled with a nickel based superalloy, Alloy 718, was studied. This material is mainly used in the aerospace industry because maintains its mechanical properties until 650ºC.

    The aim of this project has been to study different LPBF build parameters with an objective to increase the build rate, because with increased build rate the the build time can be reduced , thus saving money. However, in this project the aim is not just to find the combination that gives the best build rate, because one has to take important factors like the defect density, defect morphology, melt pool size and hardness into consideration. For this reason, in this thesis project the final aim is to find the parameters with the best build rate while maintaining low porosity so that future mechanical properties are not deteriorated.

    Using the different machines provided by Innovatum Science Park and University West the samples were prepared for further study. The samples were received as as-built samples and prepared for their further analysis. 

    After completing all the steps, ImageJ software was used for the defect study and to measure some melt pool size for their further analysis, Excel to get the main results and do some statistical analysis for the future conclusions and the software MODDE in order to improve the model that shows the relation between the main parameters of the laser power bed fusion with the main characteristics of the material.

    Finally, after doing the full analysis for the different parameters and using the software to predict and check results the main results or conclusions were obtained. It was discovered that increase the layer thickness has not a negative impact in the porosity or lack of fusion values in spite of what could be thought at the beginning. For this reason, the best results were in the DOE 120 micro m with the highest combination of hatch distance and scanning speed, whereas the laser power has not a significant influence in the build rate. The factor that has had more influence in the porosity was the hatch distance, so it is important to be careful with this parameter if it is tried to increase the build rate by increasing it. Further, for the same scan speed, if it is used a highest value of laser power the porosity will not get as worse as if it is used a lower one. 

    As further study, it would be interesting to create a prediction model for 150 micro m layer thickness and then do it in the lab to check if the results agree. If it can be used this layer thickness the improvement would be awesome because it will save lot of time and money for the built parts in the industry. Moreover, it would be attractive to study the influence of the post treatments for the main characteristics of Alloy 718

  • 269.
    Rapp Farnes, Jim
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Robotic pre-drilling of CLT panels2020Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Forestry and processing of timber have a long tradition in Sweden and the Swedish forest industry plays a significant role in the country's economy and exports. Wooden apartment buildings are on the rise in Sweden, and the technology and production methods for the construction of multi-storey apartments are in place. Cross-laminated timber (CLT), a wood product made of glued cross-laid boards of sawn timber, is a construction material proven to be effective for the construction of wooden multi-storey buildings. Swedish wood products industries need to transit from manual labour to automated production lines to remain competitive in the global market. Södra, an association of forest owners is a manufacturer of CLT panels and sees the need of implementing a new automated process for pre-drilling of CLT panels. A concept for a robotic pre-drilling application is developed through a general process of product development. A robotic application consisting of a stationary robot with dynamic material placement is selected as the best concept for the robotic pre-drilling application. The CLT panel is repositioned by a conveyor so that the robot can reach the drilling positions. For the concept to be effective, it is necessary to synchronize both the conveyor and the robot to coordinate and work together. The robotic pre-drilling application is modelled, programmed, and simulated in RobotStudio. In the simulation, an IRB 7800 robot is used, and 24 holes in angles of 30° - 90° relative to the surface normal are drilled in the CLT panel. The cycle time of the operation is three minutes.

  • 270.
    Rashedi, Mahdi
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Soto Vallejos, Nicolas
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Undersökande studie om Lönsamhet med Vehicle-2-Grid2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Swedish distribution network is facing many new challenges, such as an increasing introduction of renewable energy sources, such as wind power, and an ever-growing electric car fleet. This means that it is becoming increasingly difficult to plan production and that a greater power consumption arises because of more electric cars in traffic. A possible solution to this is to introduce battery systems to store produced electricity when the energy requirement is low. In this way, it can return the stored energy when the energy demand increases. But since the cost of this solution is the main reason why it is not implemented, a second solution is to use the existing batteries in the electric cars to regulate the fluctuation of energy, through price regulation of electricity. Therefore, in this report, we examine whether it is profitable for the electric car owner to participate in such a system.Various legal requirements and regulations that apply at the charging station and installation rules are described, as well as how to implement and maintain relevant rules. The report also explains the financial support, of up to 50% of the total investment cost, that can be received.Two-way power transmission implies, a traditional charging pattern, where the alternating current taken from the mains is converted in a car or charger into direct current. Which in turn, through a separate converter, lowers the voltage to a suitable level and stores the energy in the battery. In addition, as a complement to the traditional charging, there is the possibility to discharge the battery by supplying energy to the grid by converting from direct current to alternating current which is called Vehicle 2 Grid (V2G). In this study, a script is created to calculate whether a profit can be generated by buying and selling energy based on spot prices with vehicle-2-grid. For this, a model is constructed with a fixed efficiency regardless of the charge rate. The model also contains daily travel at specific times in three different cases where scenarios with V2G are compared to similar scenarios without V2G. All cases where V2G was used gave revenue, however Case1 showed to be the most profitable scenario for V2G in this study. Results for Case1 showed an approx. SEK 1600 gross cost with approx. SEK 1000 as income from V2G for the year 2015. Which means a decrease of 28% in total costs compared to a similar scenario with no V2G. The charge level always varies between 30% to 90% so the battery always has enough charge to be able to run for daily use. Other scenarios in the study may provide a little more revenue but considering the long-term effects of charging and discharging on the battery Case1 is seen as the best possible scenario with moderate revenue and less stress than other scenarios.

  • 271.
    Ringström, Sebastian
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    IP Camera Security Analysis focused on Firmware Reverse Engineering2019Independent thesis Basic level (professional degree), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    This project is focused on the security of IP cameras. The project provides an in-depth approach to conducting firmware reverse engineering as a means of finding potential vulnerabilities that can in turn be used to extract sensitive information (video feed, accounts, passwords and more) from the IP camera or be used as launching point for further attacks into the infrastructure that the IP camera belongs to.

    The project looks at 4 different firmware's from 3 manufacturers; the A and B versions of the D-Link DCS-932L Cloud Camera, the TP-Link NC200 300Mbps Cloud Camera and the Tenvis TH692 Outdoor HD camera. During the reverse engineering of the firmware's belonging to previously mentioned devices a vulnerability checklist is applied to the process in order to provide a structured approach while searching through the firmware. Every firmware looked at during this project was based on an old Kernel with the same potential exploitable vulnerability.

    Wi-Fi default passwords were found for the D-Link firmware versions along with plenty of information in regarding to the wireless parameters such as DHCP and DNS addresses. Tenvis TH692 contained 2 hard-coded passwords that were cracked within 80 minutes with the use of John the Ripper. TP-Link NC200 contained 1 hard-coded password that was almost instantaneously cracked.

  • 272.
    Rosenbäck, Ritva
    et al.
    University West, Department of Engineering Science, Division of Production Systems.
    Lantz, Björn
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering. Technology Management and Economics, Chalmers University of Technology, 412 96 Gothenburg (SWE).
    Rosén, Peter
    Department of Business Administration, University of Gothenburg, 405 30 Gothenburg (SWE).
    Hospital Staffing during the COVID-19 Pandemic in Sweden.2022In: Healthcare, E-ISSN 2227-9032, Vol. 10, no 10, article id 2116Article in journal (Refereed)
    Abstract [en]

    Staff management challenges in the healthcare system are inherently different during pandemic conditions than under normal circumstances. Surge capacity must be rapidly increased, particularly in the intensive care units (ICU), to handle the increased pressure, without depleting the rest of the system. In addition, sickness or fatigue among the staff can become a critical issue. This study explores the lessons learned by first- and second-line managers in Sweden with regard to staff management during the COVID-19 pandemic. A mixed-methods approach was used, with preliminary qualitative interview (n = 38) and principal quantitative questionnaire (n = 272) studies, based on principal component and multiple regression analyses. The results revealed that the pandemic created four types of challenges relating to staff management: staff movement within hospitals; addition of external staff; addition of hours for existing staff through overtime and new shift schedules; and avoidance of lost hours due to sickness or fatigue. Furthermore, the effects of these managerial challenges were different in the first wave than in later waves, and they significantly differed between the ICU and other units. Therefore, a greater proactive focus on staff management would be beneficial in future pandemic situations.

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  • 273.
    Roshäll, Oskar
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Konstruktion av kretskort för provlåda2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This diploma thesis covers the development of the test equipment RUSUTU which is a test equipment that K3 Elprojektering uses during test and commissioning in control system facilities. The connection of the test equipment is today a time-consuming work and the purpose of this project has been to simplify the connection, through a common circuit board including all functions. Today a function for circuit-breaker simulation is missing in the equipment and a part of the work has been to develop such a function. The front plate and de circuit board is constructed in cad and this part of the work has taken up a large part of time in the project.

    RUSUTU is used for tests in control system facilities and the aim is primarily for power system protection: directional protection, overcurrent protection, earth fault protection, differential protection and busbar protection. To measure signals for relay protection instrument transformers are used. Instrument transformers are divided in current- and voltage transformers. Moreover, arc guards and pressure guards are an additional protection for the switchgear against short-circuits, arcs and pressure rise.

    RUSUTU is equipped with phase indication, polarity test, signal simulation and indication test. The phase indication is used to identify unlabeled conductors in a cable. Polarity tests are used when connecting instrument transformers to determine polarity. Signal simulation is used to simulate 0-20 mA. Indicator tests are used for sensors with alternating contacts.

    RUSUTU's test box is developed with a function breaker simulation that replaces the indication test. The circuit boards are replaced with a common, new polarity function. The function of the circuit-breaker simulation is to receive and send circuit-breaker switch signals between the circuit-breaker and the control system. The circuit-breaker simulator is based on a bistable relay with two alternating outputs.

    The result is a circuit board with function for phase indication, polarity test, signal simulation and indication test. The circuit board is considered a time-saving solution during the assembly work of the test box.

  • 274.
    Ryling, Simon
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Konceptframtagning av CNC-program: Vid nyinstallation2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Parker in Trollhättan manufactures hydraulic-pumps and hydraulic-motors for mobile applications. The front houses for one of their pump series are today manufactured in a machine park from the 80s. The production is adapted for the old CNC-machines and the deburring of the front housings is largely done manually. Parker has invested in a new CNC-machine, an OKUMA MA600II. Before the machine is installed, Parker wants to investigate the possibilities available to make the manufacture of the front houses more effective in the new machine and identify opportunities for automatic machine deburring that frees up time for the operators. Parker also wants to develop a CNC-program concept before the machine is installed so that the test run of the program can begin when the installation is complete.

    By carrying out a time study on the deburring moments and an operation mapping of the machining process, the current situation has been mapped in order to analyze and find improvement proposals. For the deburring, improvement proposals have been developed and compared to be compiled in a priority list on which ones should be tested first. Improvement proposals for the manufacturing process have been developed and a new operating list has been compiled to compare the proposals to the present and evaluate their effects. A program concept for the new multi-operation mill has been developed where subprograms and the main program's structure have been established and an instruction for block numbers, subprogram numbers and variable selection has been developed.

    The project identified possibilities for improvement in manufacturing and the improvements cut down the theoretically calculated cycle time by 8 minutes and 48 seconds, an improvement of 30.5 %. The program structure instruction enables the creation of standardized new programs that facilitate their understanding and readability. The conclusion of the project is that the new machine will be able to make the manufacture of the front housings more effective and there are opportunities for introducing automatic machine deburring.

  • 275.
    Rönnlund, Dennis
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Utredning av möjligheterna för solceller och energilager i västra delarna av Härjeåns elnät2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor's thesis has been carried out on behalf of Rejlers Sweden AB at their office in Gothenburg. A customer to Rejlers, Härjeåns, foresees a future exploitation in the ski areas located in the west parts of Härjedalen, resulting in a higher power demand. This thesis investigates if the expected load increase between year 2025 and 2035 in two of the transformer stations could be covered by local production in the grid from solar panels combined with battery storage, alternatively if it can reduce the transformer peak load. Further it has also been investigated if a new planned 40-kV transmission line can be dimensioned as a line with a dimension that only requires single poles instead of a construction with double poles.

    During the work load data from the grid-owner has been analyzed and compared with the predicted load increase in the area. Based on this work a new load profile has been constructed and used during calculations on solar panels, energy store and loading of transformers and lines.

    The results show that in current situation, with available technology, there is no option that could contribute with sufficient power and energy while being economically justifiable. The estimated investment cost is considerably higher than to strengthen the grid traditionally. For facilities such as solar panels and energy storage it is recommended to start in small scale. Based on the work performed it was shown that the predicted load for year 2035 only requires a transmission line of diameter 329mm² and that this line can be built with elemental poles.

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  • 276.
    Saarela, Karolina
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Solberg, Malin
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Hållbarhetsredovisning: Risker, möjligheter och gapanalys inför GRI-rapportering på GKN Aerospace Sweden2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The bachelor thesis is about sustainability reporting at GKN Aerospace Sweden (GAS) in Trollhättan. Companies that report their impact on the environment and society has increased. One way to report the effects on economic, environmental and social sustainability is through sustainability reporting, where GRI standards can be used. GRI stands for Global Reporting Initiatives and is an independent organization that produces global guidelines for sustainability reporting. The owner of GAS, Melrose Industries, centrally produces a sustainability report for the entire group, but a part of GAS environmental plan is to produce a sustainability report for the unit in Trollhättan.

    The purpose of the thesis was to develop a basis for GAS further assessment of how the company can proceed with sustainability reporting in accordance with GRI. The two main questions identified were what risks and opportunities exists with GRI reporting, and what GAS needs to do before sustainability reporting is possible.

    In order to answer the two main questions, a case study and a survey were performed. The case study consisted of literature studies to form an idea of how the GRI standards work. Benchmarking was performed to see how other companies work with sustainability reporting. The interviewed companies were Goodpoint and Saab, which both use the GRI standards. To get an even broader view of the subject, Melrose Industries and MTU Aero Engines sustainability reports have been studied. The survey consisted of interviews with the management at GAS and two experts at the company, to identify what material topics from the GRI standards were relevant to report. A gap analysis has also been performed to see what GAS have in place and what needs to be done before a sustainability report is possible.

    The results of the work include risks and opportunities with GRI reporting, and a gap analysis on what material topics and indicators were available and measurable. Some of the risks with GRI reporting were that companies can choose not to report negative aspects and that the report can be used to create an idealized picture of a company's situation. The opportunities with GRI reporting were that it can create credibility, strengthen relationships with society, create learning within the organization, show awareness and more. The gap analysis showed 27 gaps that GAS need to handle before a sustainability report is possible. Furthermore, the company needs to clarify what sustainability means to them, and how an organization of the work with sustainability reporting could look like.

  • 277.
    Sabelsjö, Emanuel
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Kunskap driver ständiga förbättringar2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To be a competitive and successful company over time it is not enough to have a good product. Factors such as adaption, flexibility and innovation are required to survive and be successful. In order to obtain these factors, a certain characteristic is required: the ability to learn. Calling a company for a “learning organization” is the biggest recognition that can be given. To be a learning organization, continuous improvements are required. In order to reach the level required to learn and improve, a number of steps must be passed on the road. To begin with, there must be a will. After that, skills and knowledge are required, which are then translated into actions. Of these actions, learning and improvement are then achieved. In order to reach the top, a stable foundation is required. The first step, will, is a prerequisite that must be. The next step is competence. So to be successful with continuous improvement, it is a prerequisite to have relevant knowledge. The purpose of this thesis is to identify key areas of knowledge in the work with continuous improvement and to link the knowledge with the success of the improvement work. Thus, it is thought that the results will show which areas make companies successful with the improvement work. The thesis has been done at C2 Management, a consulting company in Stockholm, which helps companies to establish continuous improvements. C2 Management uses an internet based improvement management system, System C2™. There, customers can handle all types of improvement issues such as complaints, customer opinions and deviations. As a first step in the work, a literature study was performed in which six important areas of knowledge linked to continuous improvement were identified. In addition, a case study was performed to identify the impact of the different areas on the improvement work. The case study included interviews with improvement managers on six different units within the same business. The interviews consisted of open questions and questionnaires with predefined answers, where the units were able to rank the knowledge skills in different areas. To see the units status in the improvement work, statistics from System C2™ were analyzed, as the units are customers to C2 Management. The patterns that were distinguished when the statistics and the knowledge rankings were studied is that the areas leadership and way of working are the areas that are most important to possess high competence in, in order to be successful with the improvement work. Date: May 23, 2018 Author(s): Emanuel Sabelsjö

  • 278.
    Samuelsson, Axel
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Framtagning av utvärderingsmodell för mindre energiproduktionsanläggning2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today's society is in a constant need of energy to function. Heating and cooling of homes and workplaces, operation of house holding and industrial machines and much more. The energy used is often associated with electricity, but it does not necessarily have to be so. For the purpose of heating and cooling, low-value sources of energy, such as residues from the public sector, can be used with good economy and good environmental performance as a result.

    Ramboll Energy, in Vänersborg is consulted by customers for developing competent solutions for how buildings and processes will be supplied with energy. Ramboll have a good insight in finding the best solution to produce energy, but the amount of work for doing so can be reduced.

    The methods of producing energy are many and finding which one of the methods that is most optimal can be a resource-consuming process. Many factors and parameters are involved which all shall be linked to the customer's prerequisites and generate a result. Geo heating, district heating and pellet boilers do all have the capacity to deliver enough energy, to the customer, with a power requirement up to 10MW. The best way to suit the customer can be an assessment model.

    The empiricism that forms the basis of the model has been created by reading books, previous student essays and research reports, searching information on websites and by holding conversations with subject-oriented staff. The implementation phase for developing a model has been divided into parts, such as identifying requirements, effect- and economically limiting parameters, collecting associated costs and climate conditions. Furthermore, a model was created, where customer-specific values are to be entered and a result of which energy source is the best for customer is generated.

    The model has been divided into three parts - a checklist with identified requirement parameters used as a course screening tool, a plant-size calculation tool, and a life cycle cost calculation tool with simplified life cycle analysis. The result has been verified with a number of different scenarios that, depending on the needs, delivered results that vary according to the need.

  • 279.
    Sandström, Kristina
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Sjögren, Karin
    Johansson, Kristina
    University West, Department of Social and Behavioural Studies, Division of Psychology, Pedagogy and Sociology.
    Students Sense of belonging and social media2018In: VILÄR Abstraktbok / [ed] Kristina Johansson, Trollhättan: Högskolan Väst , 2018, p. 8-8Conference paper (Other academic)
    Abstract [en]

    Students who participate in a work-integrated learning (WIL) program - such as Cooperative Education during their university studies are often better prepared for the labour market compared to students who do not receive discipline specific practical experience. But does this better preparedness come with a price? Students who participate in WIL programs compared to non-WIL students often have less access to social support networks and the university community due to their alternating academic and work terms.There is reason to believe that the construct of belonging may have especially important implications among university students. There has been growing attention in recent years to mental illness amongst post-secondary students, particularly during their first few years of university study (Conley, Kirsch, Dickson, & Bryant,2014; Storrie, Ahern, & Tuckett, 2010). Research suggests that a sense of school belonging among university students may help buffer the stress associated with the transition to university (Brunwasser, 2012). Pittman and Richmond (2008), for example, found that students who experienced a positive change in their sense of university belonging throughout their first year tended to experience a drop in levels of anxiety and depression related internalizing behavioural problems. A study by Friedlander, Reid, Shupak, and Cribbie (2007), found that when compared to parental social support, higher levels of perceived social support from friends better predicted a healthy social, emotional, and overall adjustment to university among first-year university students. While evidence points to a relation between peer support and sense of belonging and university students' academic and psychological outcomes, such measures do not account for the impact of Social Media (SM) use. This study aims to understand and describe students perception on the role social media play in sense of belonging and peer support and what the relationship(s) arebetween sense of belonging, peer support, social media and well-being. Is really work integrated learning models a way of supporting the transition between H.E and W.L or are we creating other barriers that's needs to be overcome? This study comprise of a questionnaire and focus groups interviews. 164 individuals completed a 30-45 minutes long questionnaire in English, in the end of the questionnaire the students could choose to say yes to participate in a focus group, and it resulted in five focus groups including 15 students representing all four faculties. Preliminary results indicate that the students emphasize the importance of peer-support during both their academic studies and work periods. The Students seem to find solutions trying to achieve this through SM, it becomes a natural tool and creates a platform for students to connect and support each other virtually. In the presentation we will illustrate more results.

  • 280.
    Sandén, David
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Trifunovic, Daniel
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Teknisk renhet och metrologi vid tillverkning av flygmotorkomponenter2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This paper presents work performed at GKN Aerospace, a first-tier supplier of civil and military aircraft components, as well as space propulsion. Their Engine Systems Centre of Excellence, located in Trollhättan Sweden, manufactures complex products of high quality. However, with regards to Technical Cleanliness, there are some reoccurring issues not dissimilar to ones found across other manufacturing companies. To improve a process, its parameters need to be measured and monitored in order to lay the foundation for knowledge and future decision-making. In processes related to cleaning and purifying, measurement and monitoring have proved to be troublesome in various ways, mainly related to the inherent subjectivity.

    A diffuse, industry-wide problem such as this, needs to be approached from different angles and broken down in manageable parts, while not losing sight of the whole. Semi-structured interviews were performed with personnel in varying roles. Various theoretical models were used to aid the investigation, allowing the problem to be stratified. Benchmarking and a Case Study were used for additional data collection, strengthening the research being performed.

    The work resulted in targeted solutions for some of the partial problems which are crucial in the transition from cleanliness to technical cleanliness. While more work remains, this report can be advantageously used to form the basis for future endeavors. Elusive parameters such as packaging still-times, while are not directly measurable in the context of its effects on cleanliness, are still important parts of the workflow, and should not be neglected. Future targeted actions with a holistic perspective, combined with internal education, will result in increased awareness of technical cleanliness. This is the solution to the measurability problem and eventually leads to a more efficient manufacturing process. 

  • 281.
    Schmidt, Chatchano
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Al Saeedi, Ali
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Alternativa material för kablagekanal med fokus på miljövänlighet2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A material study commissioned by Lear Corporation was conducted to explore possible alternatives to materials that the company can use in its manufacture of cabling ducts in cars. The study was based on the material used by Lear today, Polyamide 66, which was used as a reference material. The study focused on finding a cheaper material that is more environmentally friendly than the reference material to the extent that it contributes to less water consumption and less carbon dioxide emissions and carbon dioxide equivalents in production. It should also be recyclable or be biodegradable.

    The study was conducted through data collection via literature studies and study of previously performed research and tests in the area of plastics during the entire project. Brainstorming was an important step in the initial process of the study when all proposals were presented on the table. Then the alternatives were evaluated to generate the most suitable option for the cabling ducts.

    The study led to the result that PET was the material that best met Lear's requirements and wishes out of the alternatives examined. It showed good mechanical and thermal properties for the intended purpose, combined with a low price and low environmental impact, both in terms of production and recycling. The result could have been enhanced by doing tests on the materials examined, which, however, was not possible in this study because of the extensive number of material alternatives. The purpose of the study is considered to be fulfilled since a study of pure polymers and composites, both from fossil and renewable sources, has been conducted. The goal has also been achieved since a cheaper, recyclable material with less environmental impact than the reference material has been selected.

  • 282.
    Schneider, Tobias
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Correlation analysis of heat treatment distortion: Investigation in a case-hardened driveshaft2021Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Heat treatment is an unavoidable process that distorts hardened parts. This geometrical change has to be considered for the ensuing manufacturing steps. A suitable option to get knowledge about a process is to look at the existing data. This investigation was done at Pankl Racings Systems AG in Austria. The aim was to check if there are any statistically significant relations between the geometrical change caused by heat treatment, also known as distortion, and the hardness parameters for the surface and core of the parts and the case hardness depth. The project focuses on one specific part, a driveshaft used in a gearbox for motorbikes, to finalize the investigation within the given time frame. This project serves as a foundation for further investigation of Big Data analytics to gain in-depth knowledge ofdistortion for various heat-treatment processes. The method of choice is correlation analysis. It is essential to know all manufacturing steps as well as the measurement value acquisition. The most tedious process was acquiring valid data since such an investigation had never been done before at Pankl. After preparing the gathered data, it was analyzed in statistics software. The analysis showed a strong correlation between the geometrical change in length of the driveshaft and the case hardness depth. Further, the surface and the core hardness showed a significant correlation with distortion as well. However, for some chosen geometrical characteristics, not enough data was available to perform a meaningful analysis. For the company, this investigation gave new insights into the heat treatment process. It serves as a basis for further investigation. The process of data acquisition will be of importance in upcoming projects. 

  • 283.
    Schnur, Christopher
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Electron Beam - Powder Bed Fusion Of Alloy 718: Influences Of Contour Parameters On Surface And Microstructural Characteristics2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Additive Manufacturing (AM) is an uprising manufacturing process for parts with complex geometries and low production quantities. Within the layer-wise building process, less additional processes are needed, to produce the parts. This allows a building of parts within a reasonable time- and costs-range. Especially industries, such as aerospace industry, can profit from AM. Electron beam – Powder bed fusion (EB-PBF) is a common technique, within AM, to produce metallic parts out of special alloys such as Alloy 718. This superalloy is a Nickle-Iron based alloy that has high mechanical properties, even in elevated temperatures (up to 650ºC). The combination of such material properties with high geometrical freedom creates new opportunities for the industry. However, it must be noted that a significant drawback of AM-techniques is the need for post-processing because of surface roughness- and microstructural characteristics. Commonly, the produced parts utilize mechanical post process such as milling to provide good surface roughness and dimensional accuracy. To reduce the surface roughness in the contour region, and therefore reduce the amount of mechanical post-processing, the present survey elaborates the effect of relevant parameters on contours such as the number of contours, scanning speed, focus offset and beam current. By using Design of Experiments (DOE), two batches were carried out: one screening batch and a two-level-full factorial design. In those batches, 15×15×15 mm cubes were printed with various parameters and, after that, analysed by using White light interferometry (WLI), Optical microscopy (OM) and Scanning electron microscopy (SEM). Furthermore, the program ImageJ was used to perform porosity and melt pool measurements.

    It had been observed that the number of contours had quite a considerable impact on the final surface roughness and the number of defects. Samples with two contours, instead of only one, tend to have a lower surface roughness. Nevertheless, the parameters and their interaction were found to have fundamental effects on the resulting surface roughness and microstructure.

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  • 284.
    Seidl, Kristoffer
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Sundström, Alexander
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Förstudie i installation av laddstationer för elbilar i en bostadsrättsförening2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This degree project consists of a pre-study in the form of a preliminary planning for a possible construction of charging infrastructure at the Silvertärnan 1 housing cooperative in Trollhättan. The purpose of this project was to conduct an exploratory study of the potential value, methodology and conditions, both technical and economic, for this development. The objective was to deliver a preliminary planning regarding these conditions. Electric vehicles are gaining popularity as time passes and technology evolves. In order to meet the increasing demand for charging these vehicles, more charging stations need to be installed. This applies to public areas, but also villas and housing cooperatives. Hence, it is a topical discussion within housing cooperatives in the event of an installation being of interest. It may be important for these housing cooperatives to be at the forefront of this development in order to maintain their attractive status as housing is adapted to keep up with the development of technology that takes place. The current housing cooperative, Silvertärnan 1, comprises 148 apartments with associated garages. The report contains the theory behind the work and a draft proposal for electric car charging infrastructure in the housing cooperative. The proposal contains a situation assessment of the conditions that exist, both technical and economic, where existing facilities, which consists of cold garages with lightning installations and engine pre-heaters, have been investigated and available power has been calculated. Based upon this, three scenarios with different degrees of development have been formulated, these scenarios consist of 6, 33 and 148 charging stations to be installed. With the scenarios as a basis a design has been created for all three of them, Scenario 1 and 2 have been projected to the installation level, while scenario 3 has been planned more casually when assessed as technically and economically unreasonable. A cost calculation has been performed on scenarios 1 and 2 according to the price of different contractors, and a scalable cost base has also been developed. The report also contains a discussion of the technical and economic results of this project as well as a reflection of the benefit to society that the expansion can lead to. Following an analysis of the technical and economic aspects of the project, the project team has determined that scenario 1 is most appropriate and cost-effective to proceed with. Therefore, it is recommended to initially perform the installation at a small scale to subsequently expand the installation if necessary. The project team finds that the project's goals have been met to some extent, but further planning is required before development takes place.

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  • 285.
    Selin, David
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Sammanställning och analys av felstatistik på komponentnivå inom Göteborg Energi Nät ABs mellanspänningsnät2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Göteborg Energi Nät AB (hereafter GENAB) is responsible for the power supply for most part of Gothenburg. As the grid age, demands are set on GENAB to proactively replace the components that is approaching its technical lifetime before unplanned interruptions occur. In this context, reliable data for the electrical components are of great importance and these data are today a shortcoming at GENAB.

    The purpose of this investigation was to analyze interruption-reports, compile the causes to the interruptions in the medium voltage grid and identify those cases where components have been responsible for the interruptions. GENAB will thereafter use the statistics in future reinvestment planning and risk analysis.

    What kind of components that have caused the interruptions was investigated and appropriate factors to compile the statistics were identified. Suggestions on how the statistics can be reported in the future to keep it current and searchable was also given.

    Every interruption in GENABs medium voltage grid, within the years 2014 to 2016 was analyzed and the interruption-reports which are written after each interruption formed the base for the investigation. For every interruption, there is a specific number, AO-number, and by searching on this number in a computer system called EAM, more information on many of the interruptions have been obtained. A folder called "Elnät" have also been useful due to different kind of documents in that folder which sometimes turned out to be helpful. The software dpSpatial have also been a good help to find causes to the interruptions. Two interviews have been made with project leaders.

    It turned out that 170 out of 325 analyzed interruptions were caused by components. Joints and cables where the components with most faults while the other components caused significantly less interruptions.

    Conclusions are that it seemed like both old joints like cast iron-joints and oil-joints as well as new joints like EPKJ could cause many interruptions. Among the joints that were unknown, the ones within the age range 41-50 years caused most interruptions.

    The cables FCJJ and AXKJ were the types with the highest fault rate per kilometer and actions should be taken to review the possibility to exchange cables of FCJJ within the age range 41-50 years that contain several joints in the same age rate.

  • 286.
    Senghore, Francis
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Yasenov, Gürsel
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Förbättringsverktyg inom distributionslager2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A well-functioning logistics (a generic term for process which ensures that all materials and products are in right quantity and in the right place at the right time (Mattson, 2018)), throughout the entire production flow makes it easier for companies to identify potential waste (Pewe & Berglind, 2011). Companies around the world aspire to eliminate waste (Janjić, 2019). One can achieve the target through continuous improvements (Sörqvist,2004). The present study is a qualitative study which were conducted at Varner Supply AB in Vänersborg, a distribution warehouse belonging to the Norwegian fashion group Varner. The study aims to civilise an idea of how a distribution company that does not work with continuous improvements can introduce tools and working methods to work with continuous improvements. To achieve the purpose of the study, the present study intends to answer following questions: what kind of requirements should be placed on the improvement tools and working methods that will be used on Varner Supply AB, and which kind of improvement tools and working methods is met by the requirement set by VarnerSupply AB?Theory and requirements were developed through literature study, study visits, observations,and interviews. The requirements were compiled in a criteria matrix and were compared withLean tools, where 5S, 5-Why, Spaghetti diagram and PDCA were considered to fit in on thecriteria set by Varner Supply AB, as the company wanted tools that were easy to understand and use, that should not be time consuming, while optimizing documentation and problem management. The tools are then presented in contrast to the deviation stations at the external department at Varner Supply AB, where the authors to the present study theorize how the tools are suitable for the company. The tools have not been implemented at the workplace. They are suggestions to Varner Supply AB based on theory, observations, and interviews. 

  • 287.
    Singh, Anurag
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Automation of Inspection Line: Cross laminated timber quality inspection2021Independent thesis Basic level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 288.
    Sisodia, Lina
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Produktionsteknisk ingenjörseffektivitet vid GKN Aerospace Sweden2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In today's competitive society, companies are largely required to make constant improvements in their organization. In order for manufacturing industries to remain strong players in the market, they should strive for customized production, short lead times and low production costs, while at the same time striving to reduce waste and thus increase their competitiveness. An organization’s success depends on its employees’ performance. A competent workforce is the core of any successful company in order to develop processes that can meet the competitiveness of the world.

    On-the-job training is an essential part of a company’s employee development process.However, companies' learning processes can be long and inefficient. Many companies have comprehensive and traditional methods of learning without taking into account an individual's ability to learn. By optimizing a company's learning process, the company cancounteract waste in the form of unused skills that can be lost in inefficient processes.

    A case study has been carried out at GKN Aerospace Sweden AB and the purpose was to analyze how the on-the-job training process can be streamlined and suggest improvement proposals for the current training process. In addition, evaluate the theoretical effects that the improvement proposals can have from a Lean perspective. The aim of the degree project is to propose improvement proposals and evaluate the theoretical waste GKN has the opportunity to eliminate according to Lean. With the help of interviews and theories from literature studies that increased knowledge in the problem area, the author has been able to map the current learning process and thus identify bottlenecks that arise in the process. The result includes that the company should:

    1. Develop interactive courses

    2. New employees must be given the necessary qualifications and the company must apply a fail-safe method in their business system

    3. Annual revisions and adjustments / prioritization according to specific professional role

    4. Develop a training plan with supervisors, managers and new employees and distribute workloads.

    By implementing the improvement suggestions, GKN has the opportunity to shorten the learning process. In return this gives a greater opportunity to maintain the productivity and creativity of the new employees so that the company's optimization level does not deteriorate.

  • 289. Sjögren, Karin
    et al.
    Sandström, Kristina
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Johansson, Kristina
    University West, Department of Social and Behavioural Studies, Division of Psychology, Pedagogy and Sociology.
    What gender barriers do students face in WIL placements?: A comparative study between WIL and Non- WIL Students in an international empirical study.2018In: VILÄR Abstraktbok / [ed] Kristina Johansson, Trollhättan: Högskolan Väst , 2018, p. 6-6Conference paper (Other academic)
    Abstract [en]

    In an earlier project (2014-2015) we found that young adults and specifically women was a exposed group when it came to reported psychological vulnerability. This triggered us to design for a new study to learn more about their sense of belonging in and out of study context. We plan to use a mixed methods approach with individual interviews, focus groups, and a broader online survey on students that are enrolled in WIL-programs, the student need to have completed at least a practicum or coop-period prior to participation in the research study. Our next steps will be to start the ethics protocols for both the University of Waterloo and the University of Toronto. Thereafter Scotland and Sweden apply for theirs. The research questions is: What gender challenges do WIL students face that impact their career identity, sense of belonging, work self-efficacy, overall wellbeing, sociability, and transition to full-time employment after graduation? What gender specific barriers impact WIL students' perceptions of being valued in the workplace (on the team, in meetings)? What gender specific barriers impact WIL students' perceptions of how employers perceive their technical competencies? What resources do WIL students perceive are available to them from their universities and employers to help overcome these barriers? In the interactive session we will discuss both the research questions/content and the methodological approaches.

  • 290.
    Sjöö, Malin
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Karlsson, Patrik
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Teknisk-ekonomisk utvärdering av arbetsmetoder på Vattenfalls distributionsnät2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Vattenfall Eldistribution AB has the responsibility to build, operate, maintain and invest in their grid to ensure a reliable distribution of electricity to their customers. The work on the grid is carried out by entrepreneurs and in the case of planned outage, it is strived for to minimize number of the customers affected. According to the electrical safety instructions (ESA) the following working methods are used when working on the grid; live working (AMS), working in the vicinity of live parts (ANS) and dead working (AUS).

    Vattenfall Eldistribution has noticed a decrease in the number of planned work on their grid carried out without an outage. This can be found in the statistic on established switching programs from years 2011 to 2016. This study evaluates statistics about how often the work methods AUS and AMS are used on the distribution grid. The study also evaluates statistics about the reliability index SAIDI (System Average Interruption Duration Index) in order to see if the choice of work methods affects the reliability of the distribution of electricity. The reliability index SAIDI is reported to Energimarknads-inspektionen (Ei). Vattenfall Eldistribution divides it into two areas, north and south. The last part of the statistics is about accidents caused by electricity where electricians have been involved. This is analyzed to see if the choice of working method is the correlated to accidents. Furthermore, the study includes a technical-economical evaluation on the work methods AUS and AMS to find pros and cons about them.

    The percentage of live working decreased in 2011 to 2014 but increased slightly over the last two years. The biggest decrease was for maintenance work. The statistics about work that hasn't resulted in an outage couldn't be evaluated due to changed definitions. The number of interruption hours couldn't be evaluated either because of changed compilation of hours. During the period 2012 – 2016 the reliability index SAIDI was four times higher in the northern area compared to the southern area.

    During the period 2000 - 2016 the departments for grid operation and electric power supply were involved in 25 - 30 percent of all accidents caused by electricity. The main reasons for the accidents were insufficient control of operating voltage or inadequate protective measures.

    It was detected during the technical-economical evaluation that the total cost for using AMS or AUS is roughly the same. A safe working environment is the key factor when the choice of work method is decided.

  • 291.
    Skärström, Sara
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Thorén, Daniel
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    SAIDI-påverkan på grund av oselektiva felbortkopplingar: en analys baserad på Vattenfall Eldistribution AB:s nät2020Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Swedish Energy Markets Inspectorate has requirements on the electrical distribution companies regarding power quality. Both power failure and planned interruptions in the distribution of electricity is to be reported annually. These interruptions are measured by SAIDI (System Average Interruption Duration Index) and SAIFI (System Average Interruption Frequency Index). These indexes narrate the average interruption duration or interruption frequency per electrical costumer per year, in a certain area.

    This thesis was made on the behalf of Vattenfall Eldistribution AB (VEAB). The purpose of this study was to analyze the annual effect on SAIDI by selectivity issues in power systems. If VEAB wants to reach the SAIDI-goal it is necessary for a study to be carried out. The study should investigate what factors that contributes to an increased SAIDI because of selectivity issues.

    The analyze involved interruptions that had been caused by an incorrect operation of the protection systems and interruptions due to testing of these systems. Only interruptions that lasted longer than three minutes was considered.

    There are components in power systems which are supposed to disconnect the faulty part, they are called protection relays. Unfortunately, they do not detect all faults that occur in the power system. For example, the protection systems can be wrongly configurated and the faulty part will not be disconnected in a properly way.

    The result of the study is that selectivity issues have a significant effect on the annual SAIDI that is reported to Swedish Energy Markets Inspectorate. One of the main reasons to selectivity issues are for example limitations in the protection relays. In conclusion, Vattenfall Eldistribution AB can profit from an investment to decrease SAIDI that is affected by selectivity issues. Older components that lacks the calibration feature could be replaced, and already existing ones that have such a calibration feature could be re-calibrated.

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  • 292.
    Strandberg, Niklas
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Rosander, Dennis
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Moment free support of corrugated bulkhead2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Fartygskonstruktioner AB wanted to investigate an alternative design bulkhead, presented by DNV, to their reference design of the corrugated bulkheads in their oil cargo tanks. The purpose was to lower the stress in the deck, the deck longitudinals, and the corrugated bulkheads. This was achieved by identification of problems, creation of calculation models and finite element analysis of the stresses. A subject and theory research strengthened the validation of the upcoming work.

    A study was done to identify the problems. This included research of the subject and the theory behind it. With this knowledge, an analysis of the reference design was performed. A modified midship model was created based on the reference design model, which became the alternative design model. This was done in the program GeniE. When the alternative design was created, a submodel with a finer mesh was modeled. Even a modified submodelwas modeled. Properties were added to the models, and analysis in the software Xtract took place.

    The results showed different stress levels in the four models, and focus was aimed at the deck, the deck longitudinals, and the corrugated bulkheads. The reference design presented the stress value in the current ship model, and the alternative design showed the stress levels in the alternative design. In the submodel, the results were focused on the interface between the deck and the corrugated bulkheads. The same was done for the modified submodel.

    The first two analyses of the reference model and the alternative design model seemed to have a too coarse mesh to give reliable results. However, they gave a good reference value to investigate further with the submodels. In the submodel, the mesh was finer, and the results reflected values closer to reality. The modified submodel had the same mesh as the earlier submodel, and an added transverse girder decreased the stress level around the attachment between the deck and the corrugated bulkheads.

    The conclusion showed that the submodel with the alternative design bulkhead had stresses above the permissible value. The modified submodel with the transverse girder reduced these stresses to within the maximum permissible value. 

  • 293.
    Sundberg, Josefine
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Effektivisering av plåtlager på ett tillverkande företag2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    During spring 2022 this bachelor’s thesis was executed at Trestad Laser AB in Trolhättan. The purpose of the project was to identify improvement measures that could be implemented to achive increased warehouse efficiency. The aim of the study was to achieve a better utilization of the business’s storage and to minimize the proportion of non-value-creating activities. The project was limited to the company’s storage space.

    The study, which investigation design was a case study, which means that a specific case was examined to find a solution to problems identified by the employer which contained both qualitative and quantitative data. F

    For the collection of secondary data, literature studies and information obtained from the business system were used. Unorganized interviews, observations and time studies were used to collect primary data. Through the collection of primary data, it could be identified that a lot of time was spent searching for materials and moving pallets that stand in the way when obtaining material. The time studies confirmed this as an average of 80% of the time was spent on these activities. Process mapping was used to assess time spent on value-creating activities. It was then identified that most of the time spent picking was spent on non-value-creating activities that were not necessary either.

    Ishikawa diagrams were used to find the root causes of the problems that needed to be solved. The basic reasons identified resulted in similar reasons which were that the staff did not know where material should be placed as there were no marked storage places, there was a lot of material in the storage spaces, there was no developed standardized working method, low use of pallet racks and large stock balance. To find solutions to these problems, tree diagrams were used where a variant of brainstorming with the affected persons was carried out, these were based on the theoretical frame of reference that had been prepared. The improvement proposals that were generated were: implementation of 5S, investment of PDAs with bar code readers for picking and submission of materials, ABC classification and development of a standardized working method.

    The expected effects when implementing the improvement measures were a reduction of 80% in time for sheet metal picking. To eliminate the steps of searching and moving on pallets was not considered completely reasonable. The measures are also expected to helpminimize the risks of incorrect picking, better control of inventory levels and better structure of the inventory space.

  • 294.
    Svensson, Helen
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Josefsson, Alexandra
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Dimensionering av ångföljeledningar till processledningar på Preemraff i Lysekil med avseende på värmeeffekt2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Inom raffinaderier används termisk energi från ånga i system där klena rör, så kallade ångföljeledningar, monteras längs processledningar för att bibehålla processmediet vid en bestämd temperatur genom att tillföra termisk energi. Syftet är att förhindra fasomvandling i processmediet, det vill säga frysning, separering eller stelning, eller för att uppnå lämplig viskositet.Det finns risk att ångföljeledningar längs processledningar är underdimensionerade med avseende på antal ångföljeledningar och rörtyp samt typ av ånga som används. Följden blir att det avges för låg värmeeffekt från ångföljeledningar. Det kan leda till kostsamma driftstopp och behov av ytterligare installation av ångföljeledningar för att åstadkomma lämplig värmeeffekt. För utredning av dimensioneringen tillhandahölls ett beräkningsfall av Preemraff Lysekil vilket innefattande en 12" isolerad processledning innehållande pitch, en trögflytande vätska. Processmediet ska via varmhållning med ångföljeledningar ha en temperatur på 60 °C för en säker uppstart av processen, då pitchen börjar flyta vid 40 °C. En genomgång av värmeöverföringsteorin utfördes för att identifiera samband som behövdes vid beräkning av ångföljeledningars värmeöverföring till processmediet. Förluster för systemet studerades. Värmeöverföringen via den luftspalt som finns mellan ångföljeledning och processledning visade sig vara svår att beräkna. Ett förslag på matematisk beskrivning av luftspalten togs fram. Matematiska modeller ställdes upp för att beräkna processmediets temperatur vid olika arrangemang av ångföljeledningar via energisamband. Ett dimensioneringsverktyg utformades med hjälp av Visual Basic i Excel. Beräkningar validerades genom termisk FEM-analys. Resultaten visar att värmeöverföringen, då ångföljeledningen är placerad under processledningen, är komplex att beskriva och beräkna analytiskt. Värmeöverföringen från luftspalten har stor påverkan på resultatet, medan andra faktorer såsom vindhastigheter i omgivningen har mycket liten påverkan. Det föreslås att ytterligare studier för värmeöverföring via luftspalten bör utföras för att öka reliabiliteten i resultaten. Därtill behöver beräkningarna valideras med hjälp av temperaturmätningar i anläggningen. Den teoretiska del som presenteras i rapporten föreslås ligga till grund för vidareutveckling och förfining av konstruktionshjälpmedlet.

  • 295.
    Svensson, Jesper
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Olsson, Christian
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Reducering av kvalitetsbristkostnaderkopplat till råämnen2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis the cost of poor quality is investigated at a manufacturing company, proposals for improvement are presented to reduce the cost for poor quality. The work has been carriedout at Parker Hannifin in Trollhättan, which manufactures hydraulics pumps and motors. 80% of the company's internal costs of quality are linked to casted raw materials, because of this, the work has been carried out as a first step in reducing the costs of poor quality associated with raw materials. The work began with observations, interviews and data gathering to gain an understanding of the production process, the quality process and the quality problems. The information was compiled in a selection of different quality tools to see the development and scope of the various problems over time. The internal costs of quality are divided into four problem areas: "porosity", "unclean surface", "dimension errors" and "rejected products". By using an Ishikawa diagram, various flaws were identified that underlie the company's costs of poor quality. An in-depth study using five why-analysis was conducted on the major problem areas to identify root causes. Most costs of poor quality can be attributed to the supplier, large portions of the goods delivered are not within the specifications. Within the boundaries of this thesis, improvement proposals are presented to reduce the costs of deviations due to defective material. Following selected improvement proposals are recommend by the authors: • Introduction of reception control so that incorrect gods do not reach the production. • Implementation of traceability on casted raw materials to easily locate incorrect gods. Furthermore, we recommend that the company educates the staff in deviation management as well as basic training in causal analysis, to involve more people and create consensus and commitment regarding quality.

  • 296.
    Svensson, Wictor
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Haydari, Farzad
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Den samhällsekonomiska nyttan av förkortade avbrottstider i 40 kV distributionsnät2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The bachelor’s thesis has been performed for Vattenfall Eldistribution AB, below called Vattenfall. When Vattenfall is building new 40/10 kV stations they normally install circuit-breakers instead of disconnectors in the new 40 kV cable bays. However they aren’t armed with protection, so they’re only used as a coupling tool for switching operations. The work is a technic economic comparison of the socioeconomic benefits of installing protection in the new 40 kV cable bays. The interruption times will be reduced with this installation in the 40 kV distribution grids because of the more selective fault clearance of the malfunction part. The work has also involved an investigation of the benefits of powering the grids meshed instead of radial. The socioeconomic analysis is ranging over 30 years and it’s based on three parts; a) society-based interruption time costs and how it is effected by the different cases, b) the economic difference for power losses between the meshed grid and the radial grid and c) costs for protection equipment. The analysis is based on three cases, case 1: existing radial grid, case 2: radial grid + extended protection equipment and case 3: meshed grid + more advanced protection equipment. The economic calculations for interruption-times, power losses and protection equipment have been performed in Excel, load flow calculations of power losses in the program PSS/E and figures has been drawn in AutoCad. The result has shown that the financial benefit always improves in case 2, i.e. it's profitable to extend the protection equipment because of the economic value of improved costs of interruption time. The meshed system always results in a reduction of the interruption-time cost but the power losses can either decrease or increase and it depends on the configuration and the circumstances in the supplying network. Therefore, it’s not possible to make a general statement on the meshed examples. Different grids need to be investigated separately

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  • 297.
    Sörensson, Emil
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Vilhelmsson, Joakim
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Undersökning av resistansvärden i brytare och frånskiljare2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today, maintenance is performed at predetermined time intervals. Eldistribution wants to investigate the possibility of performing a preventive and more proactive maintenance instead based on the state of the asset. Therefore, Eldistribution is developing an Anläggningshälsoindex (AHI). With this, Eldistribution wants to optimize maintenance planning. An AHI consists of a number of parameters collected when inspecting the asset. The resistance in circuit breakers and disconnectors can be one of these parameters. Circuit breakers are used in the high voltage grid to break all kinds of fault currents that may occur. They can also be used to make changes in the grid during work. Disconnector is a device used to get a clear visual breakpoint. Due to its construction it can’t break currents but it can break voltage. The thesis has been carried out both as theoretical study of circuit breakers and disconnectors together with a field study during testing before operation of circuit breakers. A number of intreerviews with experts in the field has also been carried out. The thesis shows that there is a possibility of using resistance in circuit breakers as one of the preventive maintenance parameters. However, in order to be able to use the resistance of the circuit breakers as one of the parameters, it is necessary to produce clear limit values.

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  • 298.
    Sülau, Andréas
    et al.
    University West, Administration .
    Elison, Ingrid
    University West, Department of Engineering Science, Division of Welding Technology.
    Karlsson, Ann-Caroline
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Andersson, Joel
    University West, Department of Engineering Science, Division of Welding Technology.
    Hattinger, Monika
    University West, Department of Engineering Science, Division of Production Systems.
    Komplex matchning av kompetensutvecklingsbehov inom digitalisering och hållbar utveckling: En kartläggning av industriföretag i Västsverige2021In: VILÄR: 9-10 of December,2021, University West, Trollhättan, 2021, p. 13-14Conference paper (Other academic)
    Abstract [sv]

    Med allt högre krav på ett hållbart samhälle ökar behoven av en snabb och innovativ produktion med högteknologiska lösningar och ökad kompetens för att möta framtidens digitala transformation. Industrin står därmed inför stora behov av kompetens och tillgång till akademisk spjutspetsutbildning i flexibla former. Kraven på en effektiv produktion efterfrågar nya kunskaper inom områdena, produktionsteknik, digital produktion (I4.0), elektrifiering men även hållbart ledarskap. Det gäller både tekniska djupkunskaper och hur organisationen kan tar tillvara interdisciplinära kunskaper för att möjliggöra tekniklösningar för en hållbar industri. Studier visar dock en diskrepans mellan företagens förmåga att definiera kompetensbehov och akademins svårigheter att möta rätt nivå och innehåll. I Västsvenska handelskammarens rapport framgår det generellt att utbildningssystemet inte är anpassat för yrkesverksamma i näringslivet. Matchningsproblematiken mellan industri-akademi är mångfacetterad och det finns skillnader avseende definition av ämnesinnehåll, flexibla kursformer, organisationskultur, etc. Forskning visar att arbetsplatser efterfrågar både procedurkunskap (veta hur) för rutinbaserade och repetitiva uppgifter och konceptuell kunskap (veta att), som bygger på djupförståelse.

    Studiens syfte är att synliggöra industrins perspektiv på kompetensmatchning och den utgår ifrån en behovsinventering genomförd under 2021, i projektet ExSus, Hållbar och digitaliserad produktion, vid Högskolan Väst. 15 teknikchefer inom större SMF-företag intervjuades (konsult- och tillverkningsindustri) om kompetensbehov och utmaningar med digitalisering och hållbar produktion. Resultaten är mångfacetterade och visar behov av specifik och omedelbar kunskap, medan andra efterfrågar generellt lärande om Industri 4.0 (maskinlärande, sakernas internet, sensorteknik mm). Vidare finns det behov av AI (Artificiell Intelligens), fast man upplever problem med applicering. Allt fler efterfrågar kunskap utifrån ett organisations- och ledningsperspektiv, för generell förståelse, samt användning och nytta med teknologiutvecklingen, exempelvis överbryggningsutbildningar inom AI, maskinlärande och hållbar produktion i praktiken. Några efterlyser tydligare kommunikation och större samordning mellan utbildningsaktörer. Högskolan Västs nya projekt ExSus och tidigare kompetensutvecklingsprojekt, t ex ProdEx visar dock lyckade satsningar. Sammantaget finns det fortfarande ett glapp mellan akademins excellens och företagens behov av djupkunskap utifrån ett flexibelt och arbetsintegrerat lärande. Detta talar för kontinuerlig kompetensmatchning för att skapa synergier, tvärvetenskaplighet och ökad samproduktion mellan industri och akademi

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    VILÄR2021
  • 299.
    Taheri, Morteza
    et al.
    Department of Materials Engineering, South Tehran Branch, Islamic Azad University (IRN).
    Kazemi, Amirreza
    School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran (IRN).
    Gurusamy, P.
    Department of Mechanical Engineering, Chennai Institute of Technology, Chennai (IND).
    Rasoulpouraghdam, Arash
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Mohanavel, V.
    Centre for Materials Engineering and Regenerative Medicine, Bharath Institute of Higher Education and Research,Tamilnadu (IND).
    Ravichandran, M
    Department of Mechanical Engineering, K.Ramakrishnan College of Engineering, Trichy 621112, Tamilnadu (IND).
    Paidar, Moslem
    Department of Materials Engineering, South Tehran Branch, Islamic Azad University, Tehran (IRN).
    Features of hybrid laser-arc welding of GTD-111 superalloy compared to laser beam welding2022In: Materials letters (General ed.), ISSN 0167-577X, E-ISSN 1873-4979, Vol. 309, article id 131384Article in journal (Refereed)
    Abstract [en]

    In order to influence the electric arc as a heat source on the welding pool created by the laser, hybrid laser-arc welding (HLAW) and laser beam welding (LBW) methods were utilized for the welding of GTD-111 superalloy. The results showed that the HLAW method, due to the creation of more heat input, provides the conditions for the exit of gaseous pores created in the weld metal. The electric arc, located 5 mm from the laser beam, re-melted the solidified grains in the keyhole and provided the conditions for nonhomogeneous nucleation of the equiaxed grains. 

  • 300.
    Teke, Maysa
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Motion analysis of barge hulls2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Accelerations for three different barge geometries have been analyzed using diffraction solver GeniE/HydroD/WADAM. The analysis includes 5 different sea states simulated with JONSWAP spectra and 6 different headings with 45 degree spreading. Barge geometries are presented in section 5.3. One of the barges with modified geometry shows significantly reduced accelerations compared to original model. See section 6 for complete results. The table below summarizes the accelerations for the 3 barges

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