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  • 1.
    Aagaard, Sebastian
    Örebro University, School of Science and Technology.
    Demonstrating customer and business value through the implementation of a Design for Reliability Program2023Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    It is widely assumed within industry that implementation of a Design for Reliability (DfR) Program can reduce warranty costs, increase customer value and reduce Total Cost of Ownership (TCO) when applied within both product development and product improvement projects. DfR is the set of tools and related product development processes for improvement in the reliability of a product, over time through changes in the product design and the manufacturing process. This research activity aimed at demonstrating the customer and business value of implementing a DfR Program at Epiroc Surface Division. This wasinvestigated from the perspective of selected projects and product development activities focused on the Epiroc SmartROC D65 drilling rig, which has actively worked with the reliability tools.The study has concluded that implementing the DfR Program has yielded tangible business value. The enhanced Early-Life Reliability report now allows for better evaluation of business value. This value has primarily been derived from the ability to analyze reductions in warranty costs and improvements in Mean Time Between Events (MTBE), a subset of Mean Time between Failures (MTBF). A method has been developed to determine business value in terms of cost savings. From a customer perspective, when considering the TCO, it could be demonstrated that working actively with the reliability tools during product development positively affects the mechanical availability and productivity of the equipment resulting in TCO improvements. The primary tools employed in the study include the enhanced Early-Life Reliability report, and risk management tools employed during product development for early identification of potential failure modes.The study has concluded that the most significant opportunities for improving the DfR Program is by an increased collection of relevant data from the equipment’s useful life and not limited to the early life during the warranty period. Additionally, recording and reporting actual MTBFdata would be desirable to gain a broader perspective than what MTBE currently provides. Improving the quality and reliability of the input data used in tools like the Early-Life Reliability report would significantly enhance the output of this asset. It has been proven that the data can be utilized effectively. The enhanced version of the tool is not available for widespread use within the organization. However, once released, it could be a great opportunity to improve DfR in conjunction with the developed method for prioritizing efforts and demonstrating customer and business value.

  • 2.
    Abdirazak Mohamed, Warsame
    et al.
    Örebro University, School of Science and Technology.
    Sultan, Ahmed
    Örebro University, School of Science and Technology.
    Fallstudier i IDA ICE2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Case studies have been performed on a room, of which the U-values, the outer wall orientation and the ventilation system are adjusted, to study how such measures affect the energy usage of said room. The aim is to create a frame of reference that can be used to give quick answers to questions regarding the amount of energy that could be saved by applying the methods discussed in this thesis. During said studies, the U-value of a simulated room’s outer wall has been decreased from 0,15 to 0,11, and the U-value of the windows of the same room has been decreased from 1,2 to 0,9. The room has been moved so that the outer wall would face west, south, east and north respectively. Finally, the simulated room’s energy and heat balance have been simulated in two cases for a person load of 20 persons, of which the first case presents a room with a CAV (Constant Air Volume) ventilation system, and the second case presents a room with a VAV (Varied Air Volume) ventilation system. The following results are obtained from the simulations: Choosing a window with a U-value of 0.9 instead of 1.2 W/m2Kdecreases the room’s energy usage by 15 %. Choosing an outer wall with a U-value of 0.11 instead of 0.15W/m2K decreases the room’s energy usage by 9 %. Choosing a VAV ventilation system instead of a CAV ventilation system decreases the room’s energy usage by up to 16 %. Constructing the outer wall to face south decreases the room’s energy usage by 14-29 %.

  • 3.
    Abdishakour Hussein, Nassim
    et al.
    Örebro University, School of Science and Technology.
    Hassen, Abubaker Jemal
    Örebro University, School of Science and Technology.
    Lagring och transport av anläggningsmassor ur ett livscykelperspektiv2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Sweden's population is constantly increasing, and this means that people are moving more in larger cities, which is straining traffic, among other things. The Swedish Government's vision is that by 2045 the country will achieve net zero greenhouse gas emissions. In view of this, the Swedish Transport Administration has developed climate requirements and guidelines on how to carry out and design the country's infrastructure to reduce greenhouse gas emissions. To achieve the long-term goal, climate neutrality 2045, the Swedish Transport Administration has set milestones. According to Trafikverket (2020) by 2020, 2025 and 2030 climate emissions will subsequently be reduced by 15%, 30% and 50%. The purpose of the report was to investigate how bulk materials can be stored to reduce the climate impact by using a life cycle analysis so that Veidekke Sverige AB and Implenia Sverige AB, which have been commissioned to build Förbifart Stockholm (Trafikplats Hjulsta Södra), will reach future climate requirements. The report is limited to the investigation of how much CO2 eq can be saved by storing/reusing bulk materials instead of transporting them away, to be used in the project's Climate Calculation. To carry out this study, it was important to identify the fuels used in the transport of bulk materials, the weight of bulk materials and how far the bulk materials were transported. In addition, the difference was mapped from an environmental perspective if the bulk materials were stored compared to if they are transported away. The results showed that from a climate perspective it pays to handle bulk materials by storing and that the trucks use HVO as fuel. Trucks powered by HVO emit 4.045 tons of CO2 eq. When transporting bulk materials to facilities, these trucks emit approximately 78.204 tons of CO2 eq. This shows that a climate saving of about 74 tons of CO2 eq is made when storing bulk materials, which is 18 times less than if the bulk materials are transported away. In addition, the study highlights that if the transport distance had been reduced by 25%, emissions would be reduced by 19.5 tons of CO2 eq. The conclusion of this study is that storage of bulk materials and HVO as a fuel is most beneficial from an environmental perspective when handling bulk masses because climate-impacting emissions are reduced by 610% compared to diesel. However,

  • 4.
    Abdul Khaliq, Ali
    et al.
    Örebro University, School of Science and Technology.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Point-to-point safe navigation of a mobile robot using stigmergy and RFID technology2016In: 2016 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Institute of Electrical and Electronics Engineers (IEEE), 2016, p. 1497-1504, article id 7759243Conference paper (Refereed)
    Abstract [en]

    Reliable autonomous navigation is still a challenging problem for robots with simple and inexpensive hardware. A key difficulty is the need to maintain an internal map of the environment and an accurate estimate of the robot’s position in this map. Recently, a stigmergic approach has been proposed in which a navigation map is stored into the environment, on a grid of RFID tags, and robots use it to optimally reach predefined goal points without the need for internal maps. While effective,this approach is limited to a predefined set of goal points. In this paper, we extend this approach to enable robots to travel to any point on the RFID floor, even if it was not previously identified as a goal location, as well as to keep a safe distance from any given critical location. Our approach produces safe, repeatable and quasi-optimal trajectories without the use of internal maps, self localization, or path planning. We report experiments run in a real apartment equipped with an RFID floor, in which a service robot either reaches or avoids a user who wears slippers equipped with an RFID tag reader.

  • 5.
    Abdulkareem, Ahmed
    et al.
    Örebro University, School of Science and Technology.
    Al-Radi, Omar
    Örebro University, School of Science and Technology.
    Evaluating the measured grip stiffness of different carton board material properties and geometries2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This candidate thesis reports the findings of a study on an objective method for measuring grip stiffness in carton board packages with different geometries and material properties. Syntouch Biotac and a tensile tester were used as an objective method for measuring grip stiffness. In this project tests were carried out on packages with three different grammages and two different geometries. For each grammage and geometry, ten packages were tested.

    The study identifies that the applied method for the measurement of grip stiffness works to measure the change in grip stiffness regardless of where a load was applied on a package. Furthermore, the method demonstrates reasonable results. Finally, the study concluded that the objective testing method could distinguish between different material properties and geometries of the cartons being measured.

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    Evaluating the measured grip stiffness of different carton board material properties and geometries
  • 6.
    Abdullah, Aram
    et al.
    Örebro University, School of Science and Technology.
    Oktay, Samuel
    Örebro University, School of Science and Technology.
    Översyn av arbetstidsförläggning2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In order to keep up with the construction industry development it is important to be competitive. Many building contractors strive short construction times, which some- times can be difficult to achieve. In order to achieve short construction times you have to find clever solutions and a good production technic that ultimately gives a good re- sult. Shorter construction time contributes to lower costs for contractors.

    Something that is rare in today's construction industry is an extended working time this is something untried in Örebro. In the current situation a construction site opens about 07.00 and closes again for the day at 16.00, Monday to Friday. After 16.00 the construc- tion is stopped. This contributes to an inefficient use of the expenses found at a con- struction site. By extending the current working time with a few hours per day, it will hopefully contribute to a more efficiency use of the costs found at a construction site and also that the number of construction days decreases.

    In the current situation construction workers in PEAB se an extended working time negatively. According to PEAB this is because they do not understand their position in a business way within the company. PEAB argue that construction workers "permanent employment" is not a particularly secure employment. They argue that the only way to get a secure job is to PEAB in partnership with their employees can go get new jobs and deliver results together with their workers. The question then is how PEAB will be able to distinguish themselves from all other construction companies and gain a competitive advantage. According to Fredrik Ahl, Project Manager at PEAB, the solution is an ex- tended working time.

    This report aims to examine how a change in the current working time will affect the cost of a construction site. We also examined the reactions that occur among workers and officials when working hours are changing. 

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  • 7.
    Abdullah, Muhammad
    Örebro University, School of Science and Technology.
    Mobile Robot Navigation using potential fields andmarket based optimization2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A team of mobile robots moving in a shared area raises the problem of safe and autonomous navigation. While avoiding static and dynamic obstacles, mobile robots in a team can lead to complicated and irregular movements. Local reactive approaches are used to deal with situations where robots are moving in dynamic environment; these approaches help in safe navigation of robots but do not give optimal solution. In this work a 2-D navigation strategy is implemented, where a potential field method is used for obstacle avoidance. This potential field method is improved using fuzzy rules, traffic rules and market based optimization (MBO). Fuzzy rules are used to deform repulsive potential fields in the vicinity of obstacles. Traffic rules are used to deal situations where two robots are crossing each other. Market based optimization (MBO) is used to strengthen or weaken repulsive potential fields generated by other robots based on their importance. For the verification of this strategy on more realistic vehicles this navigation strategy is implemented and tested in simulation. Issues while implementing this method and limitations of this navigation strategy are also discussed. Extensive experiments are performed to examine the validity of MBO navigation strategy over traditional potential field (PF) method.

    Download full text (pdf)
    fulltext
  • 8.
    Abraham, Kaleb
    et al.
    Örebro University, School of Science and Technology.
    Lust, Andreas
    Örebro University, School of Science and Technology.
    JÄMFÖRELSE AV KLIMATPÅVERKANFÖR GLASULL OCH POLYURETAN: MPARISON OF CLIMATE IMPACT FOR GLASS WOOL AND POYURETHANE2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study examines the climate impact of the thermal insulation materials, glass wool and polyurethane. Two wall constructions with a size of one square meter are used in the study to compare their carbon footprints and determine which material has the lowest environmental impact. For the walls to be comparable, they need to have the same U-value. The study will be limited to only examining the materials from a cradle-to-gate perspective. Literature searches will be conducted for data collection. For the calculation of environmental impact, the study will examine Life Cycle Assessment (LCA), Environmental Product Declarations (EPDs), and the Boverket’s Climate Declaration.Environmental data for building materials is calculated using LCA, and from this, EPDs can be generated, which contain summarized environmental data. This study collects environmental data from EPDs Boverket’s Climate Database. U-values are calculated using the U- and λ-value method, and then the mean value is derived. Subsequently, the quantities of the materials are determined, and the walls' total Global Warming Potential (GWP) is calculated.According to the results of the study, walls with polyurethane and glass wool insulation show a significant difference in their carbon footprints. GWP calculations show that the wall with polyurethane insulation emits approximately 33 kg CO2e (carbon dioxide equivalents), while the wall with glass wool insulation emits around 17 kg CO2e. The results also indicate that the insulation layers alone exhibit a significant difference in carbon footprint, approximately 20 kg CO2e for polyurethane and 4.0 kg CO2e for glass wool. The significant difference may be attributed to the oil-based production of polyurethane. The study also found that the manufacturing stage contributes the most to the climate impact for both insulation materials.When selecting insulation materials, other material properties also need to be investigated, such as fire resistance, acoustic performance, and more. The economic aspect also plays a significant role in the selection process.From an environmental perspective, the conclusion indicates that glass wool insulation is the better choice.

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  • 9.
    Abrahamsson, Linda
    et al.
    Örebro University, School of Science and Technology.
    Anwar, Hama
    Örebro University, School of Science and Technology.
    Kvinnor i byggproduktion2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A lack of work environment and development opportunities for women in the construction production sector might lead to loss of valuable skills. It has been noted that the construction production is imprinted by an older maleculture. The construction industry is generally a male dominated industry and the gender distribution is most uneven within the construction production where there is a shortage of women.Women who work in construction production often choose to leave their role for another within the industry after a couple of years. The ambition with this study is through surveys map how women experience and have experienced their work in construction production. The goal is to find factors and patterns that later on can be used by the construction industry in effort on the matter of attracting and retaining more women in construction production. This essay has partially been written with the construction company NCC Building Örebro/Värmland. Through the results of this essay, NCC wants to be able to compare and weigh up how far they as a company have come in the gender equality issues compared to the rest of the construction production sector. In order to find answers to the essays questions a literature study and data collection was done. Multiple surveys were sent out to both women and men with different roles in the construction production. The respondents had the opportunity to answer with different alternatives and in some of the questions write comments. The surveys were sent out to women employed at NCC Örebro/värmland and to women in the industry at different workplaces and locations around Sweden. A survey was also sent out to a group of men at NCC Örebro/Värmland in order to make a comparison on equivalent questions that were asked both to women and men. The results indicate that women in the construction production do not always have the same possibilities as men. When a comparison was carried out between women at NCC Örebro/Värmland and other women with experience in the construction industry it shows a small percentage difference in certain matters that NCC has a more prosperous workplace for women.Keywords:

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  • 10.
    Abrikossova, Natalia
    et al.
    Division of Molecular Surface Physics and Nanoscience, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden .
    Skoglund, Caroline
    Division of Molecular Surface Physics and Nanoscience, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden; Division of Clinical Medicine, Department of Biomedicine, Örebro University, Örebro, Sweden.
    Ahrén, Maria
    Division of Molecular Surface Physics and Nanoscience, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden.
    Bengtsson, Torbjörn
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Division of Clinical Medicine, Department of Biomedicine, School of Health and Medical Sciences, Örebro University, Örebro, Sweden.
    Uvdal, Kajsa
    Division of Molecular Surface Physics and Nanoscience, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden.
    Effects of gadolinium oxide nanoparticles on the oxidative burst from human neutrophil granulocytes2012In: Nanotechnology, ISSN 0957-4484, E-ISSN 1361-6528, Vol. 23, no 27, article id 275101Article in journal (Refereed)
    Abstract [en]

    We have previously shown that gadolinium oxide (Gd2O3) nanoparticles are promising candidates to be used as contrast agents in magnetic resonance (MR) imaging applications. In this study, these nanoparticles were investigated in a cellular system, as possible probes for visualization and targeting intended for bioimaging applications. We evaluated the impact of the presence of Gd2O3 nanoparticles on the production of reactive oxygen species (ROS) from human neutrophils, by means of luminol-dependent chemiluminescence. Three sets of Gd2O3 nanoparticles were studied, i.e. as synthesized, dialyzed and both PEG-functionalized and dialyzed Gd2O3 nanoparticles. In addition, neutrophil morphology was evaluated by fluorescent staining of the actin cytoskeleton and fluorescence microscopy. We show that surface modification of these nanoparticles with polyethylene glycol (PEG) is essential in order to increase their biocompatibility. We observed that the as synthesized nanoparticles markedly decreased the ROS production from neutrophils challenged with prey (opsonized yeast particles) compared to controls without nanoparticles. After functionalization and dialysis, more moderate inhibitory effects were observed at a corresponding concentration of gadolinium. At lower gadolinium concentration the response was similar to that of the control cells. We suggest that the diethylene glycol (DEG) present in the as synthesized nanoparticle preparation is responsible for the inhibitory effects on the neutrophil oxidative burst. Indeed, in the present study we also show that even a low concentration of DEG, 0.3%, severely inhibits neutrophil function. In summary, the low cellular response upon PEG-functionalized Gd2O3 nanoparticle exposure indicates that these nanoparticles are promising candidates for MR-imaging purposes.

  • 11.
    Abu Baker Karim, Aria
    et al.
    Örebro University, School of Science and Technology.
    Schnelzer, Anna
    Örebro University, School of Science and Technology.
    Optimering av glidlager och utveckling av dess konstruktion2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    We have in this project become engrossed in a plain bearing design that is located in a screw press. The screw press compact an unknown mass that is confidential. Robustus have a suggestion to over dimensioning the present plain bearing. The aim of this project was to analyze and to do an optimization on some plain bearings and compare them to the present bearing and to take the choice of material and the environment where the bearing is located into account. The analysis and the optimizations showed that the current plain bearing had the best geometry but not the optimal material selection. The project is in an early state and it needs some geometrical changes. The most important of everything is that the problem has been identified with the help of the wrecked plain bearing and with an excel model.

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  • 12.
    Adayson, Christian
    et al.
    Örebro University, School of Science and Technology.
    Ashor, Denkha
    Örebro University, School of Science and Technology.
    Analysering av förbättringsförslag till byggproduktion - En studie baserad på Lean2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In recent years, production in the construction industry has evolved into a costlier construction. It has become poorer productivity and increased construction defect attributed to scientific development. They can include notes that 40% of employees time at work goes to value-added work. Construction industry is inefficient in comparison to other manufacturing industries which has 65-75% in value-added work. It is also clear that the costs in the construction sector can be reduced by 30-35%. The authorities in the various reports conveyed its current troubles and that the renovation industry needs.

    The study was done with the help of interviews and a questionnaire analysis on several construction sites to investigate if the problem persists. We chose to focus on four different construction companies working on similar sized projects. By this is obtained a greater overview of the practical work steps.

    The aim is to offer suggestions for improvement using Lean to building production.

    The work delineated on studying waste, orderliness, and continuous improvement.

    The work began with a thorough literature search and through scientific articles. This was done in order to get an overall picture of Lean and also to analyze the problem in the construction industry.

    Lean is about making work more efficiently by managing resources properly. It aims to eliminate unnecessary waste and making continuous improvements. It is an approach that has been used in manufacturing and have been designed by Toyota Automotive Group. Given its present situation in the construction industry want to study, explore opportunities Lean can bring in terms of efficiency and reduction of costs of production.

    It can be ascertained is that workplaces are still gaps in the understanding of what waste is. They are not sufficiently informed and prioritize sometimes the wrong kind of waste. During the interviews it became apparent major gaps in knowledge on the issue. Wrong priorities result that it becomes a messy workplace, which in turn makes it less environmentally friendly and can thus cause injuries.

    Through that process and maintain order in the workplace, it provides the opportunity for a larger workspace that is more flexible, higher quality of performance, employee ergonomics are better and there is less risk of injury.

  • 13.
    Adolfsson, Daniel
    et al.
    Örebro University, School of Science and Technology.
    Lowry, Stephanie
    Örebro University, School of Science and Technology.
    Andreasson, Henrik
    Örebro University, School of Science and Technology.
    Improving Localisation Accuracy using Submaps in warehouses2018Conference paper (Other academic)
    Abstract [en]

    This paper presents a method for localisation in hybrid metric-topological maps built using only local information that is, only measurements that were captured by the robot when it was in a nearby location. The motivation is that observations are typically range and viewpoint dependent and that a map a discrete map representation might not be able to explain the full structure within a voxel. The localisation system uses a method to select submap based on how frequently and where from each submap was updated. This allow the system to select the most descriptive submap, thereby improving the localisation and increasing performance by up to 40%.

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    Improving Localisation Accuracy using Submaps in warehouses
  • 14.
    Adolfsson, Daniel
    et al.
    Örebro University, School of Science and Technology.
    Magnusson, Martin
    Örebro University, School of Science and Technology.
    Alhashimi, Anas
    Örebro University, Örebro, Sweden; Computer Engineering Department, University of Baghdad, Baghdad, Iraq.
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    Andreasson, Henrik
    Örebro University, School of Science and Technology.
    Lidar-Level Localization With Radar? The CFEAR Approach to Accurate, Fast, and Robust Large-Scale Radar Odometry in Diverse Environments2023In: IEEE Transactions on robotics, ISSN 1552-3098, E-ISSN 1941-0468, Vol. 39, no 2, p. 1476-1495Article in journal (Refereed)
    Abstract [en]

    This article presents an accurate, highly efficient, and learning-free method for large-scale odometry estimation using spinning radar, empirically found to generalize well across very diverse environments—outdoors, from urban to woodland, and indoors in warehouses and mines—without changing parameters. Our method integrates motion compensation within a sweep with one-to-many scan registration that minimizes distances between nearby oriented surface points and mitigates outliers with a robust loss function. Extending our previous approach conservative filtering for efficient and accurate radar odometry (CFEAR), we present an in-depth investigation on a wider range of datasets, quantifying the importance of filtering, resolution, registration cost and loss functions, keyframe history, and motion compensation. We present a new solving strategy and configuration that overcomes previous issues with sparsity and bias, and improves our state-of-the-art by 38%, thus, surprisingly, outperforming radar simultaneous localization and mapping (SLAM) and approaching lidar SLAM. The most accurate configuration achieves 1.09% error at 5 Hz on the Oxford benchmark, and the fastest achieves 1.79% error at 160 Hz.

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    Lidar-level localization with radar? The CFEAR approach to accurate, fast and robust large-scale radar odometry in diverse environments
  • 15.
    Adolfsson, Josefine
    et al.
    Örebro University, School of Science and Technology.
    Trinh, Madeleine
    Örebro University, School of Science and Technology.
    Effektivisering av produktionsflöde för lageravdelningen2020Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has taken place at Martin G Anderson in Örebro, a company that manufactures window glasses. The company has problems with the last step of the process which is the warehouse, where big volume of glass and overtime working hours affects the workers. Purposes of the project is to find additional grounds for improvement suggestions increasing the efficiency of the production in the warehouse. As a part of the project, relevant data is collected to be able to describe the status report at the company. The status reports cover a process description and process mapping. To be able to find possible solutions to improve the current situation, the problems of the warehouse must be investigated. This is accomplished by a status analysis where relevant analytic tools as 5 Whys and 7+1 wastes of Lean production are used. The project plans are to maintain the PDCA cycle where the focus is to approach the phase Plan. The remaining phases of PDCA can thereafter be resumed by the company. The results show multiple wastes in the company, where parts of the wastes are non-value-added activities. The improvement suggestions are therefore aimed at eliminating or reducing these activities and in that way streamline the production flow in the warehouse department. One of the suggestions was theoretically analysed to determine if the suggestion was feasible or not, which resulted in it being possible to implement. Other suggestions are general ideas for the company in order to strive for a more standardised way of working. For continued work, Martin G Anderson should resume the PDCA cycle where the improvement suggestions will be implemented, evaluated and maintained a standard if the suggestions prove to have a good impact. Prerequisites are given in order to be able to attack other problem areas on the basis of this report.

  • 16.
    Afanasyev, Ilya
    et al.
    Innopolis University, Innopolis, Russia.
    Kolotov, Alexander
    Innopolis University, Innopolis, Russia.
    Rezin, Ruslan
    Innopolis University, Innopolis, Russia.
    Danilov, Konstantin
    Innopolis University, Innopolis, Russia.
    Mazzara, Manuel
    Innopolis University, Innopolis, Russia.
    Chakraborty, Subham
    Innopolis University, Innopolis, Russia.
    Kashevnik, Alexey
    ITMO University, St.Petersburg, Russia.
    Chechulin, Andrey
    ITMO University, St.Petersburg, Russia.
    Kapitonov, Aleksandr
    ITMO University, St.Petersburg, Russia.
    Jotsov, Vladimir
    University of Library Studies and Information, Sofia, Bulgaria.
    Topalov, Andon
    Technical University of Sofia, Branch Plovdiv, Plovdiv, Bulgaria.
    Shakev, Nikola
    Technical University of Sofia, Branch Plovdiv, Plovdiv, Bulgaria.
    Ahmed, Sevil
    Technical University of Sofia, Branch Plovdiv, Plovdiv, Bulgaria.
    Towards Blockchain-based Multi-Agent Robotic Systems: Analysis, Classification and Applications2019Manuscript (preprint) (Other academic)
    Abstract [en]

    Decentralization, immutability and transparency make of Blockchain one of the most innovative technology of recent years. This paper presents an overview of solutions based on Blockchain technology for multi-agent robotic systems, and provide an analysis and classification of this emerging field. The reasons for implementing Blockchain in a multi-robot network may be to increase the interaction efficiency between agents by providing more trusted information exchange, reaching a consensus in trustless conditions, assessing robot productivity or detecting performance problems, identifying intruders, allocating plans and tasks, deploying distributed solutions and joint missions. Blockchain-based applications are discussed to demonstrate how distributed ledger can be used to extend the number of research platforms and libraries for multi-agent robotic systems.

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    Towards Blockchain-based Multi-Agent Robotic Systems: Analysis, Classification and Applications
  • 17.
    Afanasyev, Ilya
    et al.
    Innopolis University, Innopolis, Russia.
    Mazzara, Manuel
    Innopolis University, Innopolis, Russia.
    Chakraborty, Subham
    Innopolis University, Innopolis, Russia.
    Zhuchkov, Nikita
    Innopolis University, Innopolis, Russia.
    Maksatbek, Aizhan
    Yildiz Technical University, Istanbul, Turkey.
    Kassab, Mohamad
    Pennsylvania State University, PA, United States.
    Distefano, Salvatore
    University of Messina, Messina, Italy.
    Towards the Internet of Robotic Things: Analysis, Architecture, Components and Challenges2019Manuscript (preprint) (Other academic)
    Abstract [en]

    Internet of Things (IoT) and robotics cannot be considered two separate domains these days. Internet of Robotics Things (IoRT) is a concept that has been recently introduced to describe the integration of robotics technologies in IoT scenarios. As a consequence, these two research fields have started interacting, and thus linking research communities. In this paper we intend to make further steps in joining the two communities and broaden the discussion on the development of this interdisciplinary field. The paper provides an overview, analysis and challenges of possible solutions for the Internet of Robotic Things, discussing the issues of the IoRT architecture, the integration of smart spaces and robotic applications.

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    Towards the Internet of Robotic Things: Analysis, Architecture, Components and Challenges
  • 18.
    Afram, Christian
    et al.
    Örebro University, School of Science and Technology.
    Demir, Kamil
    Örebro University, School of Science and Technology.
    UTVECKLINGEN AV EN JÄMSTÄLLD REKRYTERINGHur påverkar olika stora aktörer rekryteringen i byggbranschen: THE DEVELOPMENT OF AN EQUAL RECRUITMENTHow do different large actors affect recruitment in the construction industry2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The construction industry has been the least gender equal and most male-dominated in Sweden and it is important to analyze the problem and the underlying causes. Statistics show that 99 % of all craftsmen were men in 2020. The recruitment process plays an important role in the gender equality issue considering that it is where corporations show their position on both gender equality and how they work with the gender equality issues they face.  The purpose of this study is to investigate the gender equality challenges in recruitment and how major operators work with this process.  The method used is literature studies and qualitative studies. Interview studies have been key to answering our questions. We have six interviewed operators with different turnover. Respondents selected by the individuals who recruit construction related personnel to their corporation.  The results show that different large corporations with different turnovers decide how they implement gender equality in their recruitment companies in the construction industry. It has also shown a clear connection with the fact that the large corporations with the most turnover have a much better grasp of the gender equality issue and work with constant improvements and challenges, which also shows a clear structure in gender equality work within recruitment in the corporation 

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  • 19.
    Afshar, Sara
    et al.
    Mälardalens högskola, Inbyggda system.
    Moghaddami Khalilzad, Nima
    Mälardalens högskola, Inbyggda system.
    Nemati, Farhang
    Mälardalens högskola, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Inbyggda system.
    Resource Sharing among Prioritized Real-Time Applications on Multiprocessors2015In: ACM SIGBED Review - Special Issue on the 6th International Workshop on Compositional Theory and Technology for Real-Time Embedded Systems Homepage archiveVolume 12 Issue 1, 2015, p. 46-55Conference paper (Refereed)
    Abstract [en]

    In this paper, we propose a new protocol for handling resource sharing among prioritized real-time applications composed on a multiprocessor platform. We propose an optimal priority assignment algorithm which assigns unique priorities to the applications based on information in their interfaces. We have performed experimental evaluations to compare the proposed protocol (called MSOS-Priority) to the current state of the art locking protocols under multiprocessor partitioned scheduling, i.e., MPCP, MSRP, FMLP, MSOS, and OMLP. The valuations show that MSOS-Priority mostly performs significantly better than alternative approaches.

  • 20.
    Aghaie Azghandi, Mohammed Ali
    et al.
    Örebro University, School of Science and Technology.
    Ahmad, Omar
    Örebro University, School of Science and Technology.
    Byggföretagens hantering av fuktsäkerhetsprojektering – med fokus på projektörer2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Moisture damage usually occurs due to incorrect planning, design and execution throughout the construction process. These inaccuracies result in large cost of action that can be minimized or even eliminated if the moisture safety work is done properly. The design phase is an important stage and a properly implemented moisture safety design can be of great importance for the moisture safety work during the construction process. The planners’ role at this stage is to carry out a moisture safety work based on the requirements of the developer. The purpose of this exam is to find out the choice of method made by the planners’ in the implementation of moisture safety design and to review the need of competence development among the planners’ about moisture.    The two methods that have been used to achieve the purpose of this exam are interviews and literature studies. The target group in this exam is the construction companies in Sweden. The way of how the companies handle of moisture safety design is being reviewed in the design stage.  Of all involved actors in the design phase, the focus is on the planners'. Three out of five planners' are dissatisfied with their own moisture competence, which is in line with the opinion of the experts' of moisture about the planners' competence.   During the interviews, several experts' of moisture have pointed out the need for increased moisture competence among the planners'. The lack competence means that the planners' cannot consider or detect possible moisture risks during the moisture safety design. The method that is used by 80% of the planners' during moisture safety design is the ByggaF method. The planners' knowledge of ByggaF is still low according to the experts' of moisture and for this reason the planners' cannot apply entirely the ByggaF method. The tools that planners' need to have with them is knowledge and experience. In order to discover what is wrong, you need to have both the knowledge and experience about what is right.  Based on the response from both the building committee and the participants, a review of the documentation regarding the moisture safety work is not always requested by the building committee.  The conclusion is that projectors must acquire competence in both moisture and the ByggaF method.   

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  • 21.
    Agélii Genlott, Annika
    et al.
    Örebro University, Örebro University School of Business.
    Grönlund, Åke
    Örebro University, Örebro University School of Business.
    Att lära sig läsa och skriva - i nutid och för framtid2014In: Interaktiva medier och lärandemiljöer / [ed] Elza Dunkels; Simon Lindgren, Malmö: Gleerups Utbildning AB, 2014, 1, p. 155-166Chapter in book (Refereed)
  • 22.
    Ahari, Elias
    et al.
    Örebro University, School of Science and Technology.
    Eliasson, Erik
    Örebro University, School of Science and Technology.
    UNDERSÖKNING AV OMSTÄLLNINGSTIDER OCH VARIATIONER VID KARTONGMASKIN 2: EN FALLSTUDIE PÅ IGGESUND PAPERBOARD AB, IGGESUND2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Iggesund Mill manufactures bleached board that is used in exclusive packaging. Iggesund Mill is a part of the Holmen Groupand is located almost 30 scandinavian miles north of Stockholm. A strategic initiative has been launched at Iggesund Mill, which includes improving the working environment, increasing participation and increasing the ability to produce high quality board.

    In this study, changeovers and the variations that occur on the board machine 2 (KM2)have been investigated. This work has been conducted as a qualitative case study where interviews and observations have been analyzed with theoretical support. Early in the study it proved difficult to determine the changeover times at KM2. This may be due to an uncertainty regarding how to report changeovers, which creates a misleading picture of the changeover problems. The conclusion of this is that Iggesund Mill should clearly define the term "Changeover". The variety of products also leads to a lot of changeovers which leads to variations in the process that adversely affect the productivity. A recommendation for a continued work is to investigate whether the product variety can be reduced or the possibility to run larger production cycles.

  • 23.
    Ahlander, Britt-Marie
    Department of Medical and Health Sciences, Linköping University, Linköping, Sweden.
    Magnetic Resonance Imaging of the Heart: Image quality, measurement accuracy and patient experience2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background: Non-invasive diagnostic imaging of atherosclerotic coronary artery disease (CAD) is frequently carried out with cardiovascular magnetic resonance imaging (CMR) or myocardial perfusion single photon emission computed tomography (MPS). CMR is the gold standard for the evaluation of scar after myocardial infarction and MPS the clinical gold standard for ischemia. Magnetic Resonance Imaging (MRI) is at times difficult for patients and may induce anxiety while patient experience of MPS is largely unknown.

    Aims: To evaluate image quality in CMR with respect to the sequences employed, the influence of atrial fibrillation, myocardial perfusion and the impact of patient information. Further, to study patient experience in relation to MRI with the goal of improving the care of these patients.

    Method: Four study designs have been used. In paper I, experimental cross-over, paper (II) experimental controlled clinical trial, paper (III) psychometric crosssectional study and paper (IV) prospective intervention study. A total of 475 patients ≥ 18 years with primarily cardiac problems (I-IV) except for those referred for MRI of the spine (III) were included in the four studies.

    Result: In patients (n=20) with atrial fibrillation, a single shot steady state free precession (SS-SSFP) sequence showed significantly better image quality than the standard segmented inversion recovery fast gradient echo (IR-FGRE) sequence (I). In first-pass perfusion imaging the gradient echo-echo planar imaging sequence (GREEPI) (n=30) had lower signal-to-noise and contrast–to-noise ratios than the steady state free precession sequence (SSFP) (n=30) but displayed a higher correlation with the MPS results, evaluated both qualitatively and quantitatively (II). The MRIAnxiety Questionnaire (MRI-AQ) was validated on patients, referred for MRI of either the spine (n=193) or the heart (n=54). The final instrument had 15 items divided in two factors regarding Anxiety and Relaxation. The instrument was found to have satisfactory psychometric properties (III). Patients who prior CMR viewed an information video scored significantly (lower) better in the factor Relaxation, than those who received standard information. Patients who underwent MPS scored lower on both factors, Anxiety and Relaxation. The extra video information had no effect on CMR image quality (IV).

    Conclusion: Single shot imaging in atrial fibrillation produced images with less artefact than a segmented sequence. In first-pass perfusion imaging, the sequence GRE-EPI was superior to SSFP. A questionnaire depicting anxiety during MRI showed that video information prior to imaging helped patients relax but did not result in an improvement in image quality.

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  • 24.
    Ahmed, Mobyen Uddin
    et al.
    Örebro University, School of Science and Technology.
    Banaee, Hadi
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Health monitoring for elderly: an application using case-based reasoning and cluster analysis2013In: ISRN Artificial Intelligence, ISSN 2090-7435, E-ISSN 2090-7443, Vol. 2013, no 2013, p. 1-11Article in journal (Refereed)
    Abstract [en]

    This paper presents a framework to process and analyze data from a pulse oximeter which measures pulse rate and blood oxygen saturation from a set of individuals remotely. Using case-based reasoning (CBR) as the backbone to the framework, records are analyzed and categorized according to how well they are similar. Record collection has been performed using a personalized health profiling approach where participants wore a pulse oximeter sensor for a fixed period of time and performed specific activities for pre-determined intervals. Using a variety of feature extraction in time, frequency and time-frequency domains, and data processing techniques, the data is fed into a CBR system which retrieves most similar cases and generates alarm and flag according to the case outcomes. The system has been compared with an expert's classification and 90% match is achieved between the expert's and CBR classification. Again, considering the clustered measurements the CBR approach classifies 93% correctly both for the pulse rate and oxygen saturation. Along with the proposed methodology, this paper provides a basis for which the system can be used in analysis of continuous health monitoring and be used as a suitable method as in home/remote monitoring systems.

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  • 25.
    Ahmed, Mobyen Uddin
    et al.
    Örebro University, School of Science and Technology.
    Islam, Asif Moinul
    Örebro University, Örebro, Sweden.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    A case-based patient identification system using pulseoximeter and a personalized health profile2012Conference paper (Refereed)
    Abstract [en]

    This paper proposes a case-based system framework in order to identify patient using their health parameters taken with physiological sensors. It combines a personalized health profiling protocol with a Case-Based Reasoning (CBR) approach. The personalized health profiling helps to determine a number of individual parameters which are important inputs for a clinician to make the final diagnosis and treatment plan. The proposed system uses a pulse oximeter that measures pulse rate and blood oxygen saturation. The measurements are taken through an android application in a smart phone which is connected with the pulseoximeter and bluetooth communication. The CBR approach helps clinicians to make a diagnosis, classification and treatment plan by retrieving the most similar previous case. The case may also be used to follow the treatment progress. Here, the cases are formulated with person’s contextual information and extracted features from sensor signal measurements. The features are extracted considering three domain analysis:1) time domain features using statistical measurement, 2) frequency domain features applying Fast Fourier Transform (FFT), and 3) time-frequency domain features applying Discrete Wavelet Transform (DWT). The initial result is acceptable that shows the advancement of the system while combining the personalized health profiling together with CBR.

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  • 26.
    Ahmed, Muhammad Rehan
    Örebro University, School of Science and Technology.
    Compliance Control of Robot Manipulator for Safe Physical Human Robot Interaction2011Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Inspiration from biological systems suggests that robots should demonstrate same level of capabilities that are embedded in biological systems in performing safe and successful interaction with the humans. The major challenge in physical human robot interaction tasks in anthropic environment is the safe sharing of robot work space such that robot will not cause harm or injury to the human under any operating condition.

    Embedding human like adaptable compliance characteristics into robot manipulators can provide safe physical human robot interaction in constrained motion tasks. In robotics, this property can be achieved by using active, passive and semi active compliant actuation devices. Traditional methods of active and passive compliance lead to complex control systems and complex mechanical design.

    In this thesis we present compliant robot manipulator system with semi active compliant device having magneto rheological fluid based actuation mechanism. Human like adaptable compliance is achieved by controlling the properties of the magneto rheological fluid inside joint actuator. This method offers high operational accuracy, intrinsic safety and high absorption to impacts. Safety is assured by mechanism design rather than by conventional approach based on advance control. Control schemes for implementing adaptable compliance are implemented in parallel with the robot motion control that brings much simple interaction control strategy compared to other methods.

    Here we address two main issues: human robot collision safety and robot motion performance.We present existing human robot collision safety standards and evaluate the proposed actuation mechanism on the basis of static and dynamic collision tests. Static collision safety analysis is based on Yamada’s safety criterion and the adaptable compliance control scheme keeps the robot in the safe region of operation. For the dynamic collision safety analysis, Yamada’s impact force criterion and head injury criterion are employed. Experimental results validate the effectiveness of our solution. In addition, the results with head injury criterion showed the need to investigate human bio-mechanics in more details in order to acquire adequate knowledge for estimating the injury severity index for robots interacting with humans.

    We analyzed the robot motion performance in several physical human robot interaction tasks. Three interaction scenarios are studied to simulate human robot physical contact in direct and inadvertent contact situations. Respective control disciplines for the joint actuators are designed and implemented with much simplified adaptable compliance control scheme.

    The series of experimental tests in direct and inadvertent contact situations validate our solution of implementing human like adaptable compliance during robot motion and prove the safe interaction with humans in anthropic domains.

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  • 27.
    Ahmed, Muhammad Rehan
    et al.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Semi-active compliant robot enabling collision safety for human robot interaction2010In: 2010 International Conference on Mechatronics and Automation (ICMA), IEEE, 2010, p. 1932-1937Conference paper (Refereed)
    Abstract [en]

    Human robot interaction (HRI) tasks requires robots to have safe sharing of work space and to demonstrate adaptable compliant behavior enabling eminent collision safety as well as maintaining high position accuracy. Robot compliance control normally can be achieved by using active compliance control of actuators based on various sensor data. Alternatively, passive devices allow controllable compliance motion but usually are mechanically complex. We proposed a unique method using semi-active compliant actuation mechanism having magneto-rheological (MR) fluid based actuator that introduces reconfigurable compliance characteristics into the robot joints. This enables high intrinsic safety coming from fluid mechanics as well as, it offers simpler interaction control strategy compared to other concurrent approaches. In this studies, we have described three essential modes of motions required for physical human system interaction. Furthermore, we have demonstrated robot collision safety in terms of static collision and experimentally validates the performance of robot manipulator enabling safe human robot interaction.

  • 28.
    Ahmed, Muhammad Rehan
    et al.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Static and dynamic collisionsafety for human robot interaction using magneto-rheological fluid based compliant robot manipulator2010In: IEEE international conference on robotics and biomimetics (ROBIO), 2010, IEEE conference proceedings, 2010, p. 370-375Conference paper (Refereed)
    Abstract [en]

    The success of human robot interaction (HRI) tasks is characterized by evaluating robot performance in terms of collision safety and position accuracy. Hence, both position accuracy and collision safety are equally indispensable. HRI refers to cognitive as well as physical interaction. Cognitive human robot interaction based on perception and awareness where as physical human robot interaction demands direct contact with the humans exhibiting adaptable compliant behavior. Therefore, development of ideal safe robot manipulator having adaptable compliant actuation is inevitable. Adaptable compliance can be achieved by using active compliant actuation requiring various sensor data or by using passive compliant devices with high mechanical complexity. We present magneto rheological fluid based compliant actuation mechanism introducing adaptable compliance directly into robotic joint with much simpler interaction control and higher intrinsic safety originating from fluid mechanics. In this study, we have discussed adaptable compliance in terms of essential modes of motion for safe physical HRI and evaluated the safety performance of our robot for static collision testing and dynamic collision testing based on impact force and head injury criterion. Finally, the experimental results validate the significance of our proposed method for both human robot collision safety and high position accuracy.

  • 29.
    Ahmed, Muhammad Rehan
    et al.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Static collision analysis of semi active compliant robot for safe human robot interaction2010In: Proceedings of the 12th Mechatronics Forum Biennial International Conference, IWF Institute of Machine tools and manufacturing , 2010, p. 220-227Conference paper (Refereed)
  • 30.
    Ahmed, Muhammad Rehan
    et al.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Two link compliant robot manipulator for physical human robot collision safety2012In: Biomedical Engineering Systems and Technologies / [ed] Ana Fred, Joaquim Filipe, Hugo Gamboa, Springer, 2012Conference paper (Refereed)
  • 31.
    Ahmed, Rehan M.
    et al.
    Örebro University, School of Science and Technology.
    Ananiev, Anani V.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Compliant motion control for safe human robot interaction2009In: Robot motion and control 2009 / [ed] Krzysztof R. Kozłowski, Berlin: Springer , 2009, p. 265-274Conference paper (Refereed)
    Abstract [en]

    Robots have recently been foreseen to work side by side and share workspace with humans in assisting them in tasks that include physical human-robot (HR) interaction. The physical contact with human tasks under uncertainty has to be performed in a stable and safe manner [6]. However, current industrial robot manipulators are still very far from HR coexisting environments, because of their unreliable safety, rigidity and heavy structure. Besides this, the industrial norms separate the two spaces occupied by a human and a robot by means of physical fence or wall [9]. Therefore, the success of such physical HR interaction is possible if the robot is enabled to handle this interaction in a smart way to prevent injuries and damages.

  • 32.
    Ahmed, Rehan M.
    et al.
    Örebro University, School of Science and Technology.
    Ananiev, Anani V.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan G.
    Örebro University, School of Science and Technology.
    Safe robot with reconfigurable compliance/stiffness actuation2009In: Proceedings of ASME/IFToMM International Conference on Reconfigurable Mechanisms and Robots. ReMAR'2009 / [ed] J. S. Dai, M. Zoppi, X. W. Kong, IEEE, 2009, p. 633-638Conference paper (Refereed)
    Abstract [en]

    Human robot interaction (HRI) in constrained motion tasks requires robots to have safe sharing of work space and to demonstrate adaptable compliant behavior Compliance control of industrial robots, normally can be achieved by using active compliance control of actuators based on various sensor data. Alternatively, passive devices allow controllable compliance motion but usually are mechanically complex. We present a unique method using a novel actuation mechanism based on magneto-rheological fluid (MRF) that incorporates reconfigurable compliance directly into the robot joints. This brings much simple interaction control strategy compared to other antagonistic methods. In this studies, we have described three essential modes of motions required for physical human system interaction. Then we have discussed their respective control disciplines. Finally, we have presented functional performance of reconfigurable MRF actuation mechanism in constrained motion tasks by simulating various HRI scenarios.

  • 33.
    Ahmed, Rehan M.
    et al.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Ananiev, Anani
    Örebro University, School of Science and Technology.
    Modeling of magneto rheological fluid actuator enabling safe human-robot interaction2008In: IEEE International Conference on Emerging Technologies and Factory Automation, 2008. ETFA 2008, 2008, p. 974-979Conference paper (Refereed)
    Abstract [en]

    Impedance control and compliant behavior for safe human-robot physical interaction of industrial robots normally can be achieved by using active compliance control of actuators based on various sensor data. Alternatively, passive devices allow controllable compliance motion but usually are mechanically complex. We present another approach using a novel actuation mechanism based on magneto-rheological fluid (MRF) that incorporates variable stiffness directly into the joints. In this paper, we have investigated and analyzed principle characteristics of MRF actuation mechanism and presented the analytical-model. Then we have developed the static and dynamic model based on experimental test results and have discussed three essential modes of motion needed for human-robot manipulation interactive tasks.

  • 34.
    Akalin, Neziha
    et al.
    Örebro University, School of Science and Technology.
    Kiselev, Andrey
    Örebro University, School of Science and Technology.
    Kristoffersson, Annica
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    An Evaluation Tool of the Effect of Robots in Eldercare on the Sense of Safety and Security2017In: Social Robotics: 9th International Conference, ICSR 2017, Tsukuba, Japan, November 22-24, 2017, Proceedings / [ed] Kheddar, A.; Yoshida, E.; Ge, S.S.; Suzuki, K.; Cabibihan, J-J:, Eyssel, F:, He, H., Springer International Publishing , 2017, p. 628-637Conference paper (Refereed)
    Abstract [en]

    The aim of the study presented in this paper is to develop a quantitative evaluation tool of the sense of safety and security for robots in eldercare. By investigating the literature on measurement of safety and security in human-robot interaction, we propose new evaluation tools. These tools are semantic differential scale questionnaires. In experimental validation, we used the Pepper robot, programmed in the way to exhibit social behaviors, and constructed four experimental conditions varying the degree of the robot’s non-verbal behaviors from no gestures at all to full head and hand movements. The experimental results suggest that both questionnaires (for the sense of safety and the sense of security) have good internal consistency.

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    An Evaluation Tool of the Effect of Robots in Eldercare on the Sense of Safety and Security
  • 35.
    Akalin, Neziha
    et al.
    Örebro University, School of Science and Technology.
    Kiselev, Andrey
    Örebro University, School of Science and Technology.
    Kristoffersson, Annica
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Enhancing Social Human-Robot Interaction with Deep Reinforcement Learning.2018In: Proc. FAIM/ISCA Workshop on Artificial Intelligence for Multimodal Human Robot Interaction, 2018, MHRI , 2018, p. 48-50Conference paper (Refereed)
    Abstract [en]

    This research aims to develop an autonomous social robot for elderly individuals. The robot will learn from the interaction and change its behaviors in order to enhance the interaction and improve the user experience. For this purpose, we aim to use Deep Reinforcement Learning. The robot will observe the user’s verbal and nonverbal social cues by using its camera and microphone, the reward will be positive valence and engagement of the user.

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    Enhancing Social Human-Robot Interaction with Deep Reinforcement Learning
  • 36.
    Akalin, Neziha
    et al.
    Örebro University, School of Science and Technology.
    Kiselev, Andrey
    Örebro University, School of Science and Technology.
    Kristoffersson, Annica
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    The Relevance of Social Cues in Assistive Training with a Social Robot2018In: 10th International Conference on Social Robotics, ICSR 2018, Proceedings / [ed] Ge, S.S., Cabibihan, J.-J., Salichs, M.A., Broadbent, E., He, H., Wagner, A., Castro-González, Á., Springer, 2018, p. 462-471Conference paper (Refereed)
    Abstract [en]

    This paper examines whether social cues, such as facial expressions, can be used to adapt and tailor a robot-assisted training in order to maximize performance and comfort. Specifically, this paper serves as a basis in determining whether key facial signals, including emotions and facial actions, are common among participants during a physical and cognitive training scenario. In the experiment, participants performed basic arm exercises with a social robot as a guide. We extracted facial features from video recordings of participants and applied a recursive feature elimination algorithm to select a subset of discriminating facial features. These features are correlated with the performance of the user and the level of difficulty of the exercises. The long-term aim of this work, building upon the work presented here, is to develop an algorithm that can eventually be used in robot-assisted training to allow a robot to tailor a training program based on the physical capabilities as well as the social cues of the users.

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    The Relevance of Social Cues in Assistive Training with a Social Robot
  • 37.
    Akalin, Neziha
    et al.
    Örebro University, School of Science and Technology.
    Kristoffersson, Annica
    School of Innovation, Design and Engineering, Mälardalen University, Västerås, Sweden.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Do you feel safe with your robot? Factors influencing perceived safety in human-robot interaction based on subjective and objective measures2022In: International journal of human-computer studies, ISSN 1071-5819, E-ISSN 1095-9300, Vol. 158, article id 102744Article in journal (Refereed)
    Abstract [en]

    Safety in human-robot interaction can be divided into physical safety and perceived safety, where the later is still under-addressed in the literature. Investigating perceived safety in human-robot interaction requires a multidisciplinary perspective. Indeed, perceived safety is often considered as being associated with several common factors studied in other disciplines, i.e., comfort, predictability, sense of control, and trust. In this paper, we investigated the relationship between these factors and perceived safety in human-robot interaction using subjective and objective measures. We conducted a two-by-five mixed-subjects design experiment. There were two between-subjects conditions: the faulty robot was experienced at the beginning or the end of the interaction. The five within-subjects conditions correspond to (1) baseline, and the manipulations of robot behaviors to stimulate: (2) discomfort, (3) decreased perceived safety, (4) decreased sense of control and (5) distrust. The idea of triggering a deprivation of these factors was motivated by the definition of safety in the literature where safety is often defined by the absence of it. Twenty-seven young adult participants took part in the experiments. Participants were asked to answer questionnaires that measure the manipulated factors after within-subjects conditions. Besides questionnaire data, we collected objective measures such as videos and physiological data. The questionnaire results show a correlation between comfort, sense of control, trust, and perceived safety. Since these factors are the main factors that influence perceived safety, they should be considered in human-robot interaction design decisions. We also discuss the effect of individual human characteristics (such as personality and gender) that they could be predictors of perceived safety. We used the physiological signal data and facial affect from videos for estimating perceived safety where participants’ subjective ratings were utilized as labels. The data from objective measures revealed that the prediction rate was higher from physiological signal data. This paper can play an important role in the goal of better understanding perceived safety in human-robot interaction.

  • 38.
    Akalin, Neziha
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Reinforcement Learning Approaches in Social Robotics2021In: Sensors, E-ISSN 1424-8220, Vol. 21, no 4, article id 1292Article, review/survey (Refereed)
    Abstract [en]

    This article surveys reinforcement learning approaches in social robotics. Reinforcement learning is a framework for decision-making problems in which an agent interacts through trial-and-error with its environment to discover an optimal behavior. Since interaction is a key component in both reinforcement learning and social robotics, it can be a well-suited approach for real-world interactions with physically embodied social robots. The scope of the paper is focused particularly on studies that include social physical robots and real-world human-robot interactions with users. We present a thorough analysis of reinforcement learning approaches in social robotics. In addition to a survey, we categorize existent reinforcement learning approaches based on the used method and the design of the reward mechanisms. Moreover, since communication capability is a prominent feature of social robots, we discuss and group the papers based on the communication medium used for reward formulation. Considering the importance of designing the reward function, we also provide a categorization of the papers based on the nature of the reward. This categorization includes three major themes: interactive reinforcement learning, intrinsically motivated methods, and task performance-driven methods. The benefits and challenges of reinforcement learning in social robotics, evaluation methods of the papers regarding whether or not they use subjective and algorithmic measures, a discussion in the view of real-world reinforcement learning challenges and proposed solutions, the points that remain to be explored, including the approaches that have thus far received less attention is also given in the paper. Thus, this paper aims to become a starting point for researchers interested in using and applying reinforcement learning methods in this particular research field.

  • 39.
    Akbar, Avan
    Örebro University, School of Science and Technology.
    HÅLLBAR FÖRVALTNING AV KONSTRUKTIONSBYGGNADER.En studie av hur effektiv förvaltning kan bidra till hållbart samhällsbyggande2022Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    fficient structures and a systematic way of working are required to maintain and keep an aging infrastructure of construction buildings to meet the requirements of road safety and function. Regular inspections and the right priorities regarding the need for operation and maintenance are an important prerequisite for long-term sustainable management and community building. This thesis aims to contribute to increased knowledge about municipal management of various types of construction buildings. By answering the three questions “How are municipal construction buildings managed?”, “What are the challenges for municipal managers?” and “Which maintenance strategies create the best conditions for ensuring maximum technical service life and thus a socio-economically sustainable development?”, the aim is investigate different structures and working methods to promote sustainable management by making the right priorities when there is a need for operation and maintenance. The methods chosen to produce this report are literature studies, interviews, email contact and meetings with a few different people in the public sector. Most of the report´s content is based on literature studies. Other methods that have been applied complement the literature study. The results showed that the majority of all municipal management of various types of construction buildings take place through the management system BaTMan with registered inspections and damages as a starting point for large and costly operation and maintenance measures. For ongoing operation and maintenance, other systems and tools are used as a complement to BaTMan. 

    The results also showed that there are a number of challenges for municipal managers who often face a rapid expansion development with many new buildings and ever-increasing number of inhabitants. Today, lack of communication and information between various municipal departments and administrations is a major problem when it comes to the construction of new construction buildings and the consequences these have for the operation and maintenance activities. Through increased cooperation across administrative boundaries, great coordination opportunities can be created to build more sustainably. From a socio-economic perspective, different maintenance measures can lead to different amounts of traffic disruption that can lead to costs for society. It is cheaper for society if the proportion of risk-reducing repairs is increased to recuse the need for urgent repairs. In addition to reduced costs, this could also lead to minor traffic disruptions.  

    The conclusion of the work is that today's and tomorrow's society is dependent on a well-unctioning infrastructure. Through a systematic approach with the right priorities,commitment and interest in efficient management, major socio-economic effects can be achieved.

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  • 40.
    Akbari, Haris
    et al.
    Örebro University, School of Science and Technology.
    Amel, Hadzic
    Svensk vindkraft2012Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
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    Vindkraftverk
  • 41.
    Al Karawi, Osama
    Örebro University, School of Science and Technology.
    Minimering av kassation i CNC processer.2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nobel Biocare is one of the world's leading companies in the manufacture of dental implants. The company is in many places around the world. The degree project was carried out at the N1 department in Karlskoga.  The company's goal is to create smart workshops and to do so, it is necessary that weaknesses in the production are identified. To find solutions, it is necessary to identity the weaknesses so that they do not arise again.  The purpose of this work is to identify the root causes of scrapping in the CNC processes and then propose three solutions to reduce/eliminate these problems. The company wants to know what opportunities they have and how they need to improve to create smart CNC workshops in 2-3 years.  To investigate the root causes of scrapping, several different analyzes were initially performed using Excel, where documented company data was used. Operators were interviewed and their own observations were noted during the visits to Nobel Biocare.  

    The study resulted in that the company should implement a timer for each operator, change tools after a certain time and have a review of how the vacuum pressure is regulated. The root cases are focused on method and man, and they are that there is a lack of quality assured routine for setting cutting fluid, tools are changed too late, inefficient method in vacuum control, sensitive tools lack sensors and too many devices are produced before control.  

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  • 42.
    Albaldawi, Hisham
    et al.
    Örebro University, School of Science and Technology.
    Kobbah, Diana
    Örebro University, School of Science and Technology.
    Dimensionering av Traverskranbana2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Crane Loads acts on runways which varies with time and cannot be treated as static loads, this allows that the static estimation is not secure enough, therefore the crane runways should be designed in such terms that it can handle static as well as dynamic crane loads.

    The work was chosen after feasibility studies which were made on the internet to get basic knowledge on the subject. The information was sought in Swedish, English and German in order to find relevant and reliable sources which deal with overhead crane runway according to Eurocode. Thanks to advice from Björn Åsted from the Steel Construction Institute (SBI), a book in German was found. In order to compare the results, a Swedish software CraneGirder EC3 was used during the project. The report contains a calculation method for a rolled section girder, calculations were based on Eurocode equations and regulations which were the design basis for the project. The report refer to how a crane runway must be designed with a high utilization level, a number of controls were made to ensure that the beam and its details, such as rail and welding are surely designed to fatigue and deformation. The design was based on load calculations for the overhead crane. Traditional calculations showed how different crane loads can be combined in load groups to achieve the highest impact on the beam, calculations showed that HEB 280 and dimensioning dominated only by load group 1 and 5. With the help of calculation software the results were largely consistent with the program but with some differences. For the delimitation that was assumed in the project the fatigue seemed to have an effect especially on some small details like weld.

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  • 43.
    Albitar, Houssam
    Örebro University, School of Science and Technology.
    Enabling a Robot for Underwater Surface Cleaning2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Biofouling build-up on submerged structures such as ships, petroleum and gas storage tanks, electric power plants, bridges, oil rigs etc. is a major problem that affects the surface material of the structure, the eventual hydrodynamic quality of the surface and in some cases the efficacy of cooling systems. Underwater cleaning is a solution to maintain submerged structures in order to assure proper functioning for as long as possible. Consequently, there has been an increased interest in the development of new technologies for robotised underwater cleaning systems.

    This thesis presents a new concept of a flexible crawling mechanism for an industrial underwater cleaning robot, which is evaluated from the viewpoint of its capability to work underwater, scanning the desired surface, and perform a cleaning task. The main research questions investigated in this thesis are: (1.) how to select the most important features in choosing the platform mechanism to fulfil the surface scanning operation, (2.) how to design the platform in order to bear the forces related to the cleaning task, (3.) how to maintain surface contact throughout cleaning, (4.) determine the significant parameters to be monitored in order to ensure stable positioning on the surface during the cleaning process and (5.) how to develop the control of actuators to realise the locomotion and to follow the desired trajectory.

    This thesis begins with a classification and discussion of the available solutions for underwater operation, taking into consideration the benefits and drawbacks, overall efficiency and environmental and human safety issues. From this survey, an underwater mobile robotic platform is designed to address the main requirements and industrial needs. Further, a study and simulation of its mobility and stability on the surface is performed and a complete scenario of the entire cleaning operation is presented. In addition, an overview of the required sensors and the control system is given. Finally, a new robotised system was developed to clean underwater surfaces with minimum active degrees of freedom. A successful simulation and real experimental results were obtained with a simplified lab-scale prototype. The thesis concludes with a summary of future works and outlook for the growing field of underwater cleaning robots.

    List of papers
    1. Underwater Robotics: Surface Cleaning Technics, Adhesion and Locomotion Systems
    Open this publication in new window or tab >>Underwater Robotics: Surface Cleaning Technics, Adhesion and Locomotion Systems
    2016 (English)In: International Journal of Advanced Robotic Systems, ISSN 1729-8806, E-ISSN 1729-8814, Vol. 13, article id 7Article in journal (Refereed) Published
    Abstract [en]

    Underwater robots are being developed for various applications ranging from inspection to maintenance and cleaning of submerged surfaces and constructions. These platforms should be able to travel on these surfaces. Furthermore, these platforms should adapt and reconfigure for underwater environment conditions and should be autonomous. Regarding the adhesion to the surface, they should produce a proper attaching force using a light-weight technics. Taking these facts into consideration, this paper presents a survey of different technologies used for underwater cleaning and the available underwater robotics solutions for the locomotion and the adhesion to surfaces.

    Place, publisher, year, edition, pages
    INTECH, 2016
    Keywords
    Underwater Robot, Underwater Cleaning, Bio-fouling, Adhesion, Locomotion
    National Category
    Computer Sciences
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-47813 (URN)10.5772/62060 (DOI)000368630700001 ()2-s2.0-85002271299 (Scopus ID)
    Available from: 2016-01-28 Created: 2016-01-28 Last updated: 2018-01-10Bibliographically approved
    2. New concept of in-water surface cleaning robot
    Open this publication in new window or tab >>New concept of in-water surface cleaning robot
    2013 (English)In: Mechatronics and Automation (ICMA), 2013 IEEE International Conference onDate 4-7 Aug. 2013, IEEE conference proceedings, 2013, p. 1582-1587Conference paper, Published paper (Refereed)
    Abstract [en]

    This paper introduces a new concept of flexible crawling mechanism to design an industrial underwater cleaning robot, which is evaluated from the viewpoint of the capability to work underwater, scanning the desired surface, and bearing the reactions. This can be used as a robotic application in underwater surface cleaning and maintenance. We designed a robot that realizes the motion by contraction and extraction using DC-motors and vacuum technology. In this study we first focused on realizing the adhesion, bearing reactions, and achieving a stable locomotion on the surface.

    Place, publisher, year, edition, pages
    IEEE conference proceedings, 2013
    Keywords
    climbing robot; inspection
    National Category
    Computer Sciences
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-30340 (URN)10.1109/ICMA.2013.6618150 (DOI)000335375900267 ()2-s2.0-84887901379 (Scopus ID)978-1-4673-5557-5 (ISBN)
    Conference
    2013 IEEE International Conference on Mechatronics and Automation (ICMA), 4-7 aug. 2013, Takamatsu, Japan
    Available from: 2013-08-27 Created: 2013-08-27 Last updated: 2018-01-11Bibliographically approved
    3. In-water surface cleaning robot: concept, locomotion and stability
    Open this publication in new window or tab >>In-water surface cleaning robot: concept, locomotion and stability
    2014 (English)In: International Journal of Mechatronics and Automation, ISSN 2045-1067, Vol. 4, no 2, p. 104-115Article in journal (Refereed) Published
    Abstract [en]

    This paper introduces a new concept of flexible crawling mechanism in the design ofindustrial in-water cleaning robot, which is evaluated from the viewpoint of work and operationon an underwater surface. It enables the scanning and cleaning process performed by water jets,while keeping stable robot position on the surface by its capacity to bear and compensate the jetreactions. Such robotic platform can be used for cleaning and maintenance of various underwatersurfaces, including moving ships in the open sea. The designed robot implements its motions bycontraction and expansion of legged mechanism using standard motors and suction cupstechnology. In this study we focus at the conditions for achieving enough adhesion for keepingcontinuous contact between the robot and the surface and robot stability in different situations forthe basic locomotions.

    Place, publisher, year, edition, pages
    IEEE, 2014
    Keywords
    underwater robot, crawling robot, underwater surface cleaning
    National Category
    Computer Sciences
    Identifiers
    urn:nbn:se:oru:diva-35987 (URN)10.1504/IJMA.2014.062338 (DOI)2-s2.0-84904859302 (Scopus ID)
    Available from: 2014-08-19 Created: 2014-08-19 Last updated: 2019-08-30Bibliographically approved
    4. Stability study of underwater crawling robot on non-horizontal surface
    Open this publication in new window or tab >>Stability study of underwater crawling robot on non-horizontal surface
    2014 (English)In: Mobile Service Robotics: Clawar 2014: 17th International Conference on Climbing and Walking Robots and the Support Technologies for Mobile Machines: Poznan, Poland 21 - 23 July 2014, Singapore: World Scientific, 2014, p. 511-519Conference paper, Published paper (Refereed)
    Abstract [en]

    This paper introduces a study of a concept of exible crawling mechanism todesign an industrial underwater cleaning robot, which is evaluated from theviewpoint of the capability to work underwater, scanning the desired surface,and bearing the reactions. This can be used as a robotic application in under-water surface cleaning and maintenance. In this study we focused on realizingthe adhesion on the surface in stationary and in motion, bearing reactions,enabling the needed locomotion types for scanning, and achieving the stabilityin dierent situations on the surface.

    Place, publisher, year, edition, pages
    Singapore: World Scientific, 2014
    Keywords
    Crawling robot, underwater, locomotion, stability
    National Category
    Computer Sciences
    Identifiers
    urn:nbn:se:oru:diva-35985 (URN)000342693100061 ()2-s2.0-85007347787 (Scopus ID)978-981-4623-34-6 (ISBN)
    Conference
    Clawar 2014: 17th International Conference on Climbing and Walking Robots CLAWAR, Poznan, Poland, 21 - 23 July, 2014
    Available from: 2014-08-19 Created: 2014-08-19 Last updated: 2018-01-11Bibliographically approved
    5. Layered mission control architecture and strategy for crawling underwater cleaning robot
    Open this publication in new window or tab >>Layered mission control architecture and strategy for crawling underwater cleaning robot
    2015 (English)In: International Journal of Mechatronics and Automation, ISSN 2045-1059, Vol. 5, no 2/3, p. 114-124Article in journal (Refereed) Published
    Abstract [en]

    This paper presents the mechanical design and the control system architecture of anunderwater robot, developed for bio-fouling cleaning surfaces. The robotic system presented herehas been designed to improve the productivity, reduce the environmental impacts, and excludethe hazards for the operators. The control system has a layered structure which is distributed intotwo blocks: cleaning robot, and on-board base station connected with power and control cablesand a water hose, to facilitate different modes of operations and to increase the system reliability.A low level control has been implemented on the robotic platform. The onboard station designedto be in different layers of the control system: manual, semiautonomous and autonomous modes.A scaled prototype has been implemented and tested to prove the concept, and to make certainthat the mechanical design and the chosen control system are perfectly suited to the mainfunctions of the robotic system.

    Place, publisher, year, edition, pages
    InderScience Publishers, 2015
    Keywords
    underwater robots, layered control system, crawling robots, bio-fouling cleaning
    National Category
    Computer Sciences
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-49753 (URN)10.1504/IJMA.2015.075957 (DOI)2-s2.0-84973596360 (Scopus ID)
    Available from: 2016-04-11 Created: 2016-04-11 Last updated: 2018-01-10Bibliographically approved
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  • 44.
    Alderholm, Daniel
    et al.
    Örebro University, School of Science and Technology.
    Torstensson, Mattias
    Örebro University, School of Science and Technology.
    Funktionsbaserad undersökning av BENTLEYS POWERCIVIL FOR SWEDEN och Novapoint 19 DCM2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The thesis was accomplished in cooperation with WSP Civils in Örebro in the

    spring of 2014. WSP Civil is in the consulting business of construction orientated

    in roads and terrain. Tools of engineering are crucial to be able to produce a

    good result. Therefore between the years of 2012 and 2013, WSP did an investigation

    regarding to which program would suit their demands. The projects task

    was to compare the existing tool Novapoint with a potential future program

    Bentleys PowerCivil for Sweden.

    The process was accomplished by creating a fictional road in both programs. Different

    functions were compared in a matrix table to be able to get a result in an

    illustrative way.

    The result in this rapport is in favor of PowerCivil for Sweden. It is mainly because

    of their templates but also because of their possibility to apply standards

    to the programs functions.

  • 45.
    Alexandersson, Tobias
    Örebro University, School of Science and Technology.
    Examensarbete Moelven Valåsen AB.2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Moelven Valåsen AB sawmill will within a 5-year period increase production from 375,000 𝑚3to approximately 500,000 𝑚3per year by building a new saw line. This has more led to the company going up from 2 shifts to 3 shifts to be able to meet this demand. This has led to the finished goods inventory before the customer has become full, and as a result the company has had to stand still. To investigate this, this thesis has investigated what the flow of the finished goods inventory looks like with the help of some tools to analyze the flow but at the same time develop the problems that may be the basis for this problem of the inventory becoming full. What has been concluded is that there are many different challenges to solving this problem. This thesis has provided an overview of where the problem may be in the flow and what it is due to. What has also been developed are some improvement proposals that could benefit the company and be developed so that the capacity of the warehouse can increase and become more efficient.  

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  • 46.
    Alfredsson, Axel
    et al.
    Örebro University, School of Science and Technology.
    Knutson, Gustav
    Örebro University, School of Science and Technology.
    Analys av driftstopp i ett hyvleri2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Moelven is an industrial group that produces building materials and systems for the construction industry; with its 52 productions units in Norway, Sweden and Denmark, it is one of the biggest in Scandinavia. This study has been carried out in the planing mill at Moelven Valåsen Wood AB in Karlskoga.

    Because of the low utilization rate in the planing mill (65%), it constitutes a bottleneck, meaning it limits the capacity and flow of material, for most of the products. The purpose of the study was to analyze the stoppage in the planing mill in order to make recommendations on how the utilization rate can be increased.

    The study began with a wide perspective to identify the reasons behind this problem. A summary of all stops in the planing mill concluded that set ups of the planer made up for 30% of total stoppage. Because of this, the study was narrowed down to mainly analyze the different types of set ups, which was done through extensive observations and videotaping. The solutions and recommendations that were given are therefore almost entirely regarding set up-time reduction, and more specifically, milling set ups. The recommendations, based on the results of the study, includes:

    • Suggestions on how to separate internal and external set up.

    • Better order of tools through designing a check table.

    Standardizing the procedure by creating a routine and dividing the operators into different work roles.

    Involving everyone in the organization in order to work with continuous improvement.

    A simulation of milling set ups was done by implementing parts of the recommendations – this resulted in a setup up-time reduction of 13 minutes, which corresponds to 32.5%. Because of common denominators, such as movements, the recommendations given are likely generalizable for all set ups.

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    Analys av driftstopp i ett hyvleri
  • 47.
    Alfredsson, Svea
    Örebro University, School of Science and Technology.
    Algas mikrofilter – alternativ till testfilter2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Transporting machines and products all over the world is expensive, time-consuming, and environmentally burdensome. Cellwood Machinery is today sending a 650-kilogram test filter to potential customers so that they can evaluate the benefits of the Algas microfilter product. The customers are paper mills all over the world and Alga's microfilters are used to filter the process water needed in paper manufacturing. The company does not think that the current method is sustainable, neither financially, in terms of time or environmentally, and therefore wants to find an alternative.The task of the thesis is to find a different method than sending a test filter. The applied method must make it possible to evaluate properties of filtered process water. It also needs to be explained which factors affect the dimensioning of an Algas microfilter.In order to find an alternative to the test filter, various concept proposals have been developed. Among these, the concept proposal to use a Schopper Riegler meter in combination with a scale stood out as the best. A Schopper Riegler meter is a measuring instrument common in the paper industry. The concept has also been tested in Cellwood Machinery's laboratory. The results of these tests showed that the concept solution works. Since the tests were done in the laboratory, further work is needed to ensure that the presented solution can fully function as an alternative to the test filter. 

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  • 48.
    Algesten, Johannes
    et al.
    Örebro University, School of Science and Technology.
    Svedberg, Sofie
    Örebro University, School of Science and Technology.
    KONSTRUKTION AV AUTOMATISK PÅHASPLINGSPROCESS VID TILLVERKNING AV BANDSTÅL2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The mission that we have received is to design a device that will automate the coiling processin the manufacture of steel strip. The goal of this project is to develop a production documentation that will form the basis for further development of the product. The production documentation shall include drawings, list of components and a cost estimate. A pilot study was conducted where we visited one of the largest strip steel manufacturer to investigate the solutions they had to our problem. Based on what we saw, a concept generation was made that led to the concept that we proceeded with. In the process, we have placed great emphasis on making the design as simple as possible to get a reasonable production cost. We have also taken into account that the design will be integrated with existing equipment. Regarding cost, we have as far as possible tried to use standard components and standard dimensions of the material in the construction. Parts of the structure exposed to high forces have been analyzed by using ANSYS. The result is a construction with two arms using a belt to envelope the coil. The arm is controlled using a hydraulic cylinder, while the other is positioned when the belt is stretched. The construction will be placed above the coil and lowered when it is used.

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    KONSTRUKTION AV AUTOMATISK PÅHASPLINGSPROCESS VID TILLVERKNING AV BANDSTÅL
  • 49.
    Algotsson, Josef
    et al.
    Örebro University, School of Science and Technology.
    Lundgren, Eric
    Örebro University, School of Science and Technology.
    ELVÄGAR - Energidistribueringssystem och energiutvinningssystem2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Sweden and the EU has a lot of climate goals, to achieve these goals the use of fossil fuels must be reduced. One solution can be electric powered vehicles, when travelling long distances there is a problem to replenish fuel. The challenge is to meet the increased demand for energy - both in terms of production and distribution - in an environmentally sound manner. A literature study as well as an interview is carried out to investigate whether roads can be made smarter to promote a greener, electric vehicle traffic and the possibility of energy harvesting systems and energy distribution in the road area. The technology for energy harvesting systems and energy distribution is available, but it can always be further developed for cheaper manufacturing and more efficient products. Energy distribution systems studied are induction and conduction. The energy harvesting systems in this report are solar energy, piezoelectricity and wind power. Pilot projects in both areas exists and more projects are under development.

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  • 50.
    Alhashimi, Anas
    University of Baghdad, Baghdad, Iraq.
    Design and implementation of fast three stages SLA battery charger for PLC systems2011In: Journal of Engineering, ISSN 1726-4073, Vol. 17, no 3, p. 448-465Article in journal (Refereed)
    Abstract [en]

    New fast sealed lead acid (SLA) battery chargers must be able to charge the fully discharged batteries in a short time. In the same time, the charger must monitor the battery state of health in order to prevent over charge and to extend the battery life time.

    In this paper a Fast charger was presented to charge SLA batteries in short time and monitor the battery voltage to prevent over charge. The design was implemented practically. And 150 charger of similar type was produced for commercial use. They are now in service in different Mobile base station sites around Baghdad. It can charge a fully discharged 12V, 4.5Ah battery in less than 5 hours. To supply PLC control system on DC power to about 24 hour of continuous operation during main electricity faults.

    During one and half year of continuous operation three faults have been recorded in the 150 chargers. All of the three cases were because of bad components manufacturing.

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    Design and implementation of fast three stages SLA battery charger for PLC systems
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