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  • 301.
    Berger, Natalie
    et al.
    Örebro University, School of Science and Technology.
    Eberhardsson, Linus
    Örebro University, School of Science and Technology.
    MÅNGFALD I PRODUKTIONEN2020Independent thesis Basic level (degree of Bachelor of Fine Arts), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The construction industry is male-dominated and suffers from a lack of diversity. Studies have shown that macho culture and a rough jargon leads to people leaving the industry.NCC is one of the biggest actors on the swedish construction market and the purpose of this study was to research how NCC Building Örebro/Värmland works with questions regarding diversity and what results it has generated. Attitudes towards diversity among the employees and differences in diversity between the counties have also been researched as a part of this study.Data was collected through literature studies, interviews and a survey. The interviewees were chosen for their function in the company or their part in a specific project.A quantitative survey was performed to research the ethnic diversity in the division and to research the employees perception of the working environment and attitudes towards diversity and gender equality.The research shows that NCC are working actively with questions regarding diversity, gender equality and inclusion and that it most probably contributed to a better psychosocial work environment. However, it’s clear that macho culture and rough jargon still exists at the workplaces. The results of the research also indicates that a majority of the employees have a positive attitude towards diversity and gender equality and that they are willing to work with the issue.There are clear differences between the counties regarding diversity among the employees. The research shows that there is a larger proportion of women among the employees in the construction phase in Värmland and that it probably have contributed to positive cultural change and an improvement of the psychosocial work environment.

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  • 302.
    Berggården, Lizette
    Örebro University, School of Science and Technology.
    Flexibilitet i bostäder2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The development of Swedish society today is happening fast. With this comes that the surrounding enviroment of residental area is facing constant changes. The recidences change with the same speed as the social development. As a result floorplans of recidences have to be easy to change. To achieve easy transformable floorplans planners should pay attention to the possibility of transforming during the design stage.

    In this work flexible floorplans of residences have been studied. Flexible floorplans mean that changes can be made easily to the floorplan and at a low cost. The focus of this work have been to look at residential floorplans from two different periods. The first period is the time of the "million programme" (residential building programme during year 1965-1975 in Sweden) and the second period is the present time (year 2005-2015). The work describes why flexible floorplans are needed, which opportunities the flexibility gives, if flexibility is time-related or unchanged over time and if an open floorplan or closed floorplan affects the flexibility.

    Legislation regarding residential design has been studied to understand which rules have controlled the floorplannings during the different times. One essential difference between legislation and rules from the time periods is that in the first period, the law set the standard requirements and nowadays it sets functional requirements. The human way of life in the housing has been studied from the 1960´s until today to understand the requirements of housing development.

    The work is based on a qualitative method where facts mainly have been collected from published books that have been read critically. An analysis of floorplans from the "millione programme" and the present has been performed. The method has been successful due to having clear criteria set before the analysis to indicate if the floorplan had good flexibility or not.

    The analysis of the floorplans was made for each time period to examine if flexibility is time-related or unchanged over time. In the analysis open and closed floorplans were compared to see if the type of plan affects the flexibility. Closed floorplans represent the "million programme" period and open floorplans represent the present.

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  • 303.
    Berglund, Martin
    Örebro University, School of Science and Technology.
    Ekonomisk jämförelse av prefabricerad betong och korslimmat trä-Totalkostnad av materialen i stommarna2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The construction industry in Sweden has a goal of achieving zero net emissions of greenhouse gases by2045. At present, larger constructions are mostly built with a concrete frame, which has a high carbondioxide emission during new production. This means that the environmental goals will not be achievedunless other alternative building materials are being used to a greater extent. The material that is the bestalternative to concrete in apartment buildings is cross laminated timber (CLT), due to its durabilitycompared to regular timber. The problem with CLT is that it has such a much more expensive productioncost, that concrete frames continue to be chosen in apartment buildings. If the construction industry is tohave any chance of meeting the requirements set for the year 2045 with zero net emissions of greenhousegases, the cost of CLT must therefore be reduced in order for its use to be accelerated. The purpose of thisstudy is to produce the exact total cost difference between a prefabricated concrete frame and a CLTframe, while at the same time the building area and structure of the frames are as similar as possible. Thegoal was to prove how far the CLT has financially, until it can compete with concrete in apartmentbuildings.To make the comparison, a reference building was developed out of concrete, which is laterredimensioned to CLT for a fair comparison. The dimensioning was done by summarizing all loads byhand. These loads were later used for every part in the frame, in the calculation program Calculatis to getthe dimensions required for the demands on durability. With a new dimensioned wooden frame, twomaterial lists were produced for the different frames and compared in the Bidcon calculation program toobtain a total cost difference. This study has focused on comparing the costs of frame materials for abuilding in CLTand one in prefabricated concrete. Non-load-bearing walls, roof construction and groundstructure do not belong in the frame, and will therefore not be in the comparison.The study gave a result that showed that it is about 42% more expensive to build with a CLT frame than aprefabricated concrete frame in a 7 storey apartment building. The floor is the more expensivecomponent, while for example other parts such as balconies and load-bearing walls still proved to becheaper. According to BBR, special noise and fire requirements must be met in apartment buildings. Toachieve these, some sound insulation needs to be added to the CLT elements that are apartment separatorsand fire plasterboards in the entire frame with CLT. This leads to the CLT frame generally having agreater thickness compared to the concrete frame and also a few extra costs to keep in mind, even whenthe load-bearing material is smaller in the CLT frame. This leads to the living space of the apartments inthe CLT building being slightly smaller than in the concrete building. The conclusion is that CLT is not aneconomical alternative to prefabricated concrete according to Bidcon's databases when this study wascarried out and is 42% more expensive due to the fact that the intermediate floor has such a high cost.

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  • 304.
    Bergman, Christian
    Örebro University, School of Science and Technology.
    How Lean is Swedish Product Development?: A study of Lean practices in large Swedish companies2010Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    This master’s thesis aims to capture the essence of Lean Product Development and to evaluate to what extent Swedish companies have implemented lean principles. Previous studies in this field exemplify how methods are used by already lean practitioners, and there is a lack ofknowledge about the extent to which lean in is used in product development in industry.

    A literature review reveals a number of principles and perspectives; 5 Lean principles, 13 Lean Product Development principles, 14 Lean Management principles and 4 critical factors for Lean (or Knowledge-based) Product Development. These principles and perspectives were the starting point in developing the survey questions.

    The survey of 26 questions was sent to 67 large Swedish companies (more than 249 employees) working with product development and design. The response rate of 39 per centwas unusually high for this type of internet survey.

    The main results of the survey are that Lean methods and tools are rather extensively used in product development, but the culturehas yet not permeated the entire company. The workload of the product developmentdepartment is too high and a structured method for organizational learning is lacking.

    Recommendations for the studied companies are to reduce the workload and increase thetime for reflection, learning and process improvement. Also, the capability to implement strategies can be improved.

    Download full text (pdf)
    Bergman_C_2010_How_Lean_is_Swedish_Product_Development
  • 305.
    bergman, martin
    Örebro University, School of Science and Technology.
    Sinnenas Rum - Ytor för bastumiljö2010Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report handles the development of a graphic manual and a physical mood-board with specific number of surfaces for the sauna manufacturing company Tylö® AB in Halmstad. The reader will have a general understanding of how the semantic of a product affects its users, and how this affects the product's performance on the market. The project is based on a fairly unused method, which basically is used for; seize a target group specific feeling about a specific product to make it more optimized. In this project, it was more about the development of specific structures on surfaces, which eventually came to lead to a number of specially selected materials and surfaces for the company Tylö ® AB. The materials, together with special surfaces, probably come to create a more elegant feeling in their upcoming concepts. The method that was used to achieve the target is called Kansei Engineering.

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    FULLTEXT01
  • 306.
    Bergsten, Pontus
    et al.
    Örebro University, Department of Technology.
    Palm, Rainer
    Siemens AG Corporate Technology, Munich, Germany.
    Driankov, Dimiter
    Örebro University, Department of Technology.
    Fuzzy Observers2001In: The 10th IEEE International Conference on Fuzzy Systems (Volym:3): Meeting the grand challenge: Machines that serve people, New York, USA: IEEE conference proceedings, 2001, p. 700-703Conference paper (Refereed)
    Abstract [en]

    We consider the analysis and design of three different types of nonlinear observers for dynamic Takagi-Sugeno fuzzy systems. Our approach is based on extending existing nonlinear observer schemes, namely Thau-Luenberger and sliding mode observers, to the case of interpolated multiple local affine linear models. Then linear matrix inequality based techniques are used for observer analysis and design.

  • 307.
    Bergsten, Pontus
    et al.
    Örebro University, School of Science and Technology.
    Palm, Rainer
    Siemens AG Corporate Technology, Otto-Hahn-Ring, Munich, German.
    Driankov, Dimiter
    Örebro University, School of Science and Technology.
    Observers for Takagi-Sugeno fuzzy systems2002In: IEEE transactions on systems, man and cybernetics. Part B. Cybernetics, ISSN 1083-4419, E-ISSN 1941-0492, ISSN 1083-4419/02, Vol. 32, no 1, p. 114-121Article in journal (Refereed)
    Abstract [en]

    We focus on the analysis and design of two different sliding mode observers for dynamic Takagi-Sugeno (TS) fuzzy systems. A nonlinear system of this class is composed of multiple affine local linear models that are smoothly interpolated by weighting functions resulting from a fuzzy partitioning of the state space of a given nonlinear system subject to observation. The Takagi-Sugeno fuzzy system is then an accurate approximation of the original nonlinear system. Our approach to the analysis and design of observers for Takagi-Sugeno fuzzy systems is based on extending sliding mode observer schemes to the case of interpolated multiple local affine linear models. Thus, our main contribution is nonlinear observer analysis and design methods that can effectively deal with model/plant mismatches. Furthermore, we consider the difficult case when the weighting functions in the Takagi-Sugeno fuzzy system depend on the estimated state

  • 308.
    Bergstrand, Simon
    Örebro University, School of Science and Technology.
    Programmering av styrutrustning för vridbord vid radarmätplats2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When calibrating a radars antenna the radar is placed on a turntable that points it to a measuring point on a tower. The main task for the thesis was to write a program in National Instruments programming environment LabVIEW that can turn the turntable with an accuracy of 0.1 milliradians. The program shall be able to be used as a DLL (Dynamic-link library) in LabWindows/CVI where a number of different functions shall be able to control the turntable. Because all of the hardware is from National Instruments the software development became easy. The challenge was instead to measure the lengths and angles of the turntable and at testing be so precise that is necessary. All requirements were met but the lack of accuracy when testing makes the results a bit uncertain.Another part of the thesis was to write documents that specify requirements, interfaces and also describes how the software will be designed, tested and calibrated. For these documents the MIL-STD-498 was used that used to be an American military standard.

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  • 309.
    Bergström, Emma
    et al.
    Örebro University, School of Science and Technology.
    Hansson, Sara
    INVERKAN VID VAL AV DRAGSKIVETYP & DRAGSKIVEVINKEL PÅ YT- OCH MATERIALEGENSKAPER AV ETT USKILJNINGSHÄRDBART ROSTFRITT STÅL2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has been designed to get a better understanding of the material and its properties in wire drawing. There have been six different experiments which were conducted with two different drawing angles of three different kinds of drawing dies; regular drawing die, smaller nib and bigger nib. The experiments have been through the beginning of the production where samples have been taken out and then be analyzed in the lab. Results from tensile tests, hardness profile, martensite- and lubrication quantity measurements has been studied and led to the conclusions.

    The conclusion shows that the surface of the wire drawn with the drawing angle 12° had fewer defects than the wire drawn with 18°. Defects that were found on the wire drawn with the bigger nib 18° consisted largely of transverse cracks. Generally the results were similar in all tests for both 12° and 18°, however, the results was diverge on several tests for the smaller

    nib 12° after the drawing die.

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  • 310.
    Bergström, Per
    et al.
    Department of Engineering Sciences and Mathematics, Luleå University of Technology, Luleå, Sweden.
    Khodadad, Davood
    Department of Engineering Sciences and Mathematics, Luleå University of Technology, Luleå, Sweden.
    Hällstig, Emil
    Optronic Partner Dp AB, Skellefteå, Sweden.
    Sjödahl, Mikael
    Department of Engineering Sciences and Mathematics, Luleå University of Technology, Luleå, Sweden.
    Dual-wavelength digital holography: single-shot shape evaluation using speckle displacements and regularization2014In: Applied Optics, ISSN 1559-128X, E-ISSN 2155-3165, Vol. 53, no 1, p. 123-131Article in journal (Refereed)
    Abstract [en]

    This paper discusses the possibility of evaluating the shape of a free-form object in comparison with its shape prescribed by a CAD model. Measurements are made based on a single-shot recording using dual-wavelength holography with a synthetic wavelength of 1.4 mm. Each hologram is numerically propagated to different focus planes and correlated. The result is a vector field of speckle displacements that is linearly dependent on the local distance between the measured surface and the focus plane. From these speckle displacements, a gradient field of the measured surface is extracted through a proportional relationship. The gradient field obtained from the measurement is then aligned to the shape of the CAD model using the iterative closest point (ICP) algorithm and regularization. Deviations between the measured shape and the CAD model are found from the phase difference field, giving a high precision shape evaluation. The phase differences and the CAD model are also used to find a representation of the measured shape. The standard deviation of the measured shape relative the CAD model varies between 7 and 19 μm, depending on the slope.

  • 311.
    Bergström, Per
    et al.
    Department of Engineering Sciences and Mathematics, Luleå University of Technology, Luleå, Sweden.
    Khodadad, Davood
    Department of Engineering Sciences and Mathematics, Luleå University of Technology, Luleå, Sweden.
    Hällstig, Emil
    Optronic Partner dp AB, Skellefteå, Sweden.
    Sjödahl, Mikael
    Department of Engineering Sciences and Mathematics, Luleå University of Technology, Luleå, Sweden.
    Single Shot Shape Evaluation Using Dual-Wavelength Holographic Reconstructions and Regularization2014In: Fringe 2013: 7th International Workshop on Advanced Optical Imaging and Metrology / [ed] Wolfgang Osten, Springer Berlin/Heidelberg, 2014, p. 103-108Conference paper (Refereed)
    Abstract [en]

    The aim of this work is to evaluate the shape of a free form object using single shot digital holography. The digital holography results in a gradient field and wrapped phase maps representing the shape of the object. The task is then to find a surface representation from this data which is an inverse problem. To solve this inverse problem we are using regularization with additional shape information from the CAD-model of the measured object.

  • 312.
    Bergvall, Victor
    et al.
    Örebro University, School of Science and Technology.
    Söderberg, Jakob
    Örebro University, School of Science and Technology.
    Analys av blockkylning i tråddragning2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Wire drawing is a cold working process where a wire is forced through a die which reduces the diameter of the wire. The temperature of the wire increases during reduction due to friction and deformation. If the temperature in the wire is allowed to exceed a certain point, the wire may lose its desired mechanical properties such as the increase in strength caused by strain hardening. In order to remove heat from the wire, the capstans which the wire is coiled around is cooled by water. This thesis is written in collaboration with a company which is interested in how efficient their current cooling system is and what parameters affects that efficiency. Practical tests and simulations were conducted at Örebro University to investigate these questions. The results show that the water flow has the greatest impact on the cooling efficiency and that the rotational speeds of the capstan between 0,5 m/s and 1,5 m/s has no significant impact on the cooling efficiency. The efficiency of the cooling efficiency is decreasing palpable after 30 l/min and the maximum cooling efficiency is obtained at a water flow above 55 l/min.

    The same type of analysis should be performed while wire drawing is occurring and other shapes of the nozzles for the cooling water should be tested.

  • 313.
    Berna, Amalia
    et al.
    CSIRO Ecosystem Sciences and CSIRO Food Futures Flagship, Canberra, Australian Capital Territory (ACT), Australia.
    Vergara, Alexander
    University of California, San Diego, USA.
    Trincavelli, Marco
    Örebro University, School of Science and Technology.
    Huerta, Ramon
    University of California, San Diego, USA.
    Afonja, Ayo
    Department of Chemistry, University College London, London, UK.
    Parkin, Ivan
    Binions, Russell
    Trowell, Stephen
    Evaluating zeolite-modified sensors: towards a faster set of chemical sensors2011In: Olfaction and electronic nose: proceedings of the 14th International Symposium on Olfaction and Electronic Nose (ISOEN 2011), May 2-5, 2011, New York City, USA, American Institute of Physics (AIP), 2011, p. 50-52Conference paper (Refereed)
    Abstract [en]

    The response of zeolite-modified sensors, prepared by screen printing layers of chromium titanium oxide (CTO), were compared to unmodified tin oxide sensors using amplitude and transient responses. For transient responses we used a family of features, derived from the exponential moving average (EMA), to characterize chemo-resistive responses. All sensors were tested simultaneously against 20 individual volatile compounds from four chemical groups. The responses of the two types of sensors showed some independence. The zeolite modified CTO sensors discriminated compounds better using either amplitude response or EMA features and CTO-modified sensors also responded three times faster.

  • 314.
    Berns, H.
    et al.
    Institut für Werkstofle, Ruhr-Universität Bochum, Bochum, Germany .
    Melander, A.
    lnstitutet för Metallforskning, Stockholm, Sweden .
    Weichert, D.
    Laboratoire de Mécanique de Lille, Lille, France .
    Asnafi, Nader
    lnstitutet för Metallforskning, Stockholm, Sweden .
    Broeckmann, C.
    Institut für Werkstofle, Ruhr-Universität Bochum, Bochum, Germany .
    Gross-Weege, A.
    Laboratoire de Mécanique de Lille, Lille, France .
    A new material for cold forging tools1998In: Computational materials science, ISSN 0927-0256, E-ISSN 1879-0801, Vol. 11, no 3, p. 166-180Article in journal (Refereed)
    Abstract [en]

    A new tool material for cold forging applications was developed using numerical simulation techniques (FEM) for the design and a powder metallurgical route (HIP) for the production. The basic idea was to find an optimized microstructure of the two phase material by simulating different distributions of hard particles within the metal matrix. On the micro-scale, loading was applied by a field of deformations which was obtained by a macroscopical simulation of a particular cold forming process in bolt making. A new double dispersion microstructure was found to show the best resistance against crack propagation. Specimens were produced by hot isostatic pressing. Afterwards the new material was tested in the laboratory. Wear resistance and bending strength of the double dispersive material are comparable to a standard dispersion material with the same volume fraction of particles, but fracture toughness is increased by about 30%. Testing the new material in bolt making showed that the life time of the tool is increased by a factor of 8.

  • 315.
    Berntsson, Tomas
    Örebro University, Department of Technology.
    Anlöpning utan bly2002Conference paper (Other academic)
  • 316.
    Berntsson, Tomas
    Örebro University, Department of Technology.
    Replacement of lead baths with environment friendly alternative heat treatment processes in steel wire production2005Licentiate thesis, comprehensive summary (Other academic)
    List of papers
    1. Replacement of lead baths for the tempering of spring wire
    Open this publication in new window or tab >>Replacement of lead baths for the tempering of spring wire
    2003 (English)In: Scandinavian journal of metallurgy, ISSN 0371-0459, E-ISSN 1600-0692, Vol. 32, no 5, p. 241-246Article in journal (Refereed) Published
    Abstract [en]

    Molten lead is used for tempering of valve-spring wire. Lead has drawbacks due to slow temperature changes. In 1991 the Swedish Parliament passed a Government Bill, in which proposals were made to phase out the use of lead in the long term, primarily through voluntary measures. Tempering of SIS 2090 (SAE 9254, DIN 55SiCr7) wire with different dimensions using induction heating was tested in a pilot process line. An induction coil for six wires and two coils with different lengths designed for single wires were tested. The results showed that an induction coil for six wires gave excessive temperature and property variations between the wires. The shorter of the single wire coils gave fluctuations in temperature and properties using a 3.00-mm wire. No such fluctuations were observed with the longer coil. One of the experiments showed that the process might need time to reach stable conditions. The results so far indicate that it is possible to produce valve-spring wire with induction tempering. The process needs more control and monitoring compared to tempering in molten lead. © Blackwell Munksgaard, 2003.

    Keywords
    Automotive engineering, Lead, Wire, Monitoring
    National Category
    Engineering and Technology
    Research subject
    Mechanical Engineering
    Identifiers
    urn:nbn:se:oru:diva-4615 (URN)10.1034/j.1600-0692.2003.00648.x (DOI)000185253200003 ()2-s2.0-0141844455 (Scopus ID)
    Available from: 2007-07-12 Created: 2007-07-12 Last updated: 2023-12-08Bibliographically approved
    2. Alternatives to lead bath for patenting of high carbon steel wire
    Open this publication in new window or tab >>Alternatives to lead bath for patenting of high carbon steel wire
    2004 (English)In: Wire Journal International, ISSN 0277-4275, Vol. 37, no 5, p. 82-86Article in journal (Refereed) Published
    Abstract [en]

    The alternatives to lead bath for patenting of high carbon steel wire are discussed. It is found that it is possible to achieve properties of high-speed gas patented music wire without using a soaking furnace. Laboratory experiments with patenting in a fluidized bed, showed that the process could give the required mechanical properties for the valve spring wire. It is also found that small alterations in process parameters in the industrial trials has a large impact on the mechanical properties and microstructures.

    Keywords
    Carbon steel, Furnaces, Austenite, Mufflers, Wire drawing, Molten materials, Valves (mechanical), Quenching, Process control, High temperature effects
    Research subject
    Mechanical Engineering
    Identifiers
    urn:nbn:se:oru:diva-4582 (URN)
    Available from: 2007-07-12 Created: 2007-07-12 Last updated: 2017-10-18Bibliographically approved
    3. Material properties of induction tempered high tensile valve spring wire
    Open this publication in new window or tab >>Material properties of induction tempered high tensile valve spring wire
    2006 (English)In: Steel Research International, ISSN 1611-3683, Vol. 77, no 11, p. 836-843Article in journal (Refereed) Published
    Abstract [en]

    Most of today's hardened valve spring wires are tempered in a lead bath. The lead bath provides a stable and accurate degree of tempering of the wire, but it has environmental disadvantages and limitations in flexibility. This paper describes how induction heating can replace lead bath and how this may affect the material properties. The study includes FEM-simulations, calculation of the tempering parameter and experiments with induction tempering of three different SiCr valve spring steels carried out under pilot production. The mechanical properties of the test samples were measured. Fatigue testing of one of the steels was performed on finished springs. The results were evaluated by comparing induction-tempered wire with the conventional lead tempered reference wire. The induction tempered wire fulfilled the product requirements and corresponded in performance with the lead tempered wire.

    Place, publisher, year, edition, pages
    Düsseldorf: Verlag Stahleisen, 2006
    Keywords
    Wire, Valves (mechanical), Tempering, Lead, Thermoanalysis, Steel, Finite element method, Computer simulation, Induction tempering, Spring steel, Super clean steel, High strength steel, Silicon chromium steel
    National Category
    Engineering and Technology
    Research subject
    maskinteknik
    Identifiers
    urn:nbn:se:oru:diva-4387 (URN)
    Available from: 2007-07-12 Created: 2007-07-12 Last updated: 2017-10-18Bibliographically approved
  • 317.
    Berntsson, Tomas
    et al.
    Örebro University, Department of Technology.
    Jarl, Magnus
    Örebro University, Department of Technology.
    Material properties of induction tempered high tensile valve spring wire2006In: Steel Research International, ISSN 1611-3683, Vol. 77, no 11, p. 836-843Article in journal (Refereed)
    Abstract [en]

    Most of today's hardened valve spring wires are tempered in a lead bath. The lead bath provides a stable and accurate degree of tempering of the wire, but it has environmental disadvantages and limitations in flexibility. This paper describes how induction heating can replace lead bath and how this may affect the material properties. The study includes FEM-simulations, calculation of the tempering parameter and experiments with induction tempering of three different SiCr valve spring steels carried out under pilot production. The mechanical properties of the test samples were measured. Fatigue testing of one of the steels was performed on finished springs. The results were evaluated by comparing induction-tempered wire with the conventional lead tempered reference wire. The induction tempered wire fulfilled the product requirements and corresponded in performance with the lead tempered wire.

  • 318.
    Berntsson, Tomas
    et al.
    Örebro University, Department of Technology.
    Sapcanin, Edin
    Örebro University, Department of Technology.
    Kontinuerlig patentering av pianotråd med gaskylning: delrapport2003Report (Other academic)
  • 319.
    Berntsson, Tomas
    et al.
    Örebro University, Department of Technology.
    Sapcanin, Edin
    Örebro University, Department of Technology.
    Patentering av tråd i virvelbädd och med gaskylning: delrapport2003Report (Other academic)
  • 320.
    Berntsson, Tomas
    et al.
    Örebro University, Department of Technology.
    Sapcanin, Edin
    Örebro University, Department of Technology.
    Hede, Allan
    Örebro University, Department of Technology.
    Jarl, Magnus
    Örebro University, Department of Technology.
    Alternatives to lead bath for heat treatment of wire2003Conference paper (Other academic)
  • 321.
    Berntsson, Tomas
    et al.
    Örebro University, Department of Technology.
    Sapcanin, Edin
    Örebro University, Department of Technology.
    Jarl, Magnus
    Örebro University, Department of Technology.
    Blyfri värmebehandling av tråd2002In: Stål 2002, 2002, p. 50-51Conference paper (Other academic)
  • 322.
    Berntsson, Tomas
    et al.
    Örebro University, Department of Technology.
    Sapcanin, Edin
    Örebro University, Department of Technology.
    Jarl, Magnus
    Örebro University, Department of Technology.
    Segerberg, Sören
    Alternatives to lead bath for patenting of high carbon steel wire2003Conference paper (Refereed)
  • 323.
    Bertilsson, Anders
    Örebro University, School of Science and Technology.
    Alternative welding methods for nitrogen alloyed steel2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project explores the feasibility of the solid-state welding method direct-drive friction welding to be used as a joining method for the nitrogen alloyed steel Uddeholm Vanax SuperClean, produced via processes based on powder metallurgy. Vanax SuperClean cannot be welded using fusion welding methods where the base material melts, due to nitrogen escaping the material, resulting in inferior quality welds. The cost of the material motivates the use of Vanax SuperClean for critical parts in applications, combined with a less costly material for the remaining parts, causing alternative joining methods to be examined.

    Vanax SuperClean is friction welded to itself and to Uddeholm steel types Stavax ESR and UHB 11. Samples are prepared for a number of examinations. Microstructures of the samples are examined using microscopy, microhardness testing is carried out per the Vickers principle, retained austenite is measured using X-ray diffraction and tensile testing of the welded samples is performed. Defect-free welds are produced in all examined samples, showing that the method is suitable for Vanax SuperClean and that no preheating or slow cooling of workpieces are necessary.

    The possibility of using friction stir welding as a joining method for Vanax SuperClean is discussed.

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    Alternative welding methods for nitrogen alloyed
  • 324.
    Bertilsson, Erik
    et al.
    Örebro University, School of Science and Technology.
    Latifi, Egzon
    Örebro University, School of Science and Technology.
    OLYCKSLASTER I ETT PREFABRICERAT FLERBOSTADSHUS2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This dissertation is based on a comparison between the two different procedures on accidental actions in the Swedish norm EKS 11 and SS-EN 1991-1-7. If a construction only has a stairwell as the only emergency exit it requires that accidental actions determines. These accidental actions are categorized mainly to known and unknown accidental actions. Known accidental actions are for example collision by a vehicle or a gas leak from a gas pipe in the building. Unknown accidental actions are those loads that cannot be completely determined. Instead an analyze how to decrease the damage by accidental actions are used. The main approach is to value members as key elements, in effect making them strong enough to withstand a prescribed hazard loading. An alternative if the construction does not have any gas pipes is to use the pressure of 34 kN/m2 to represent the static equivalent from a notional gas explosion. The values in the work are based from a project constructed by the Swedish company Structor. Previously difficulties have occurred while comprehending the Eurocode’s calculation procedures therefore the new Swedish norm EKS have clarified a lot about accidental actions. The calculation procedures results in two different answers between the Eurocode and the Swedish norm EKS. The aim with this dissertation is too clarify the differences between them and perceive the reasons behind it. To be able to have a wider understanding of the subject accidental actions a screening has occurred of the Eurocode, the Swedish norm EKS and literature. The Swedish company Structor has also shared a lot of knowledge on the subject. The dissertation has been limited to accidental actions on stairwells as the only emergency exit and a comparison between the Swedish norm EKS 11 and SS-EN1-7. The outcome of the two different calculations shows two different results of the known and unknown accidental actions. The equations for calculating accidental action in the different standards considerate different things which leads to different results. The conclusion is that there always are different conditions in every project. Therefor a risk assessment should be done before the construction begins to determine which standard is the most suitable for the project.

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    fulltext
  • 325.
    Bertilsson, Jimmy
    et al.
    Örebro University, School of Science and Technology.
    Andersson, Joakim
    Örebro University, School of Science and Technology.
    Ställtidsoptimering2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Emhart Glass Ltd is a world leader in glass bottle manufacturing. They designautomated machines that shape glass bottles. In Sweden there are two factories,one in Örebro and one in Sundsvall. In Örebro they manufacture primarily spareparts and new parts for the machines while they in Sundsvall assemble themachines. There are a total of 15 factories and offices around the world with theheadquarter located in Swiss Cham.Since Emhart Glass Örebro has long setup times on some of their machines. Thisis why we want to identify the current setup process and how the setup processdiffers between operators. We will also look at whether there are anyopportunities for improvement to be made and if they have a standardized way towork. A document that describes how to setup work should be done will also bedeveloped.An excellent tool to shorten the setup time in a production is the SMED method.The philosophy behind SMED is that you should analyze and separate the innerand outer activities. Inner and outer activities mean those activities which canonly be performed when the machine is turned off, respectively those activitiesthat can be performed when the machine is in operation.In order to standardize the adjustment process so that all operators are working ina similar way it's required that you make a documentation about how the workshould be done. Therefore, checklists been developed to the operator. "Checklista- Omställning.xls" is a checklist with the purpose to be able to check which partsof the preparations they have made before the next setup work. It has beendesigned to be easy to keep track of what parts you have done if you had to workwith the machine between the trial or if you quit your shift and leaving parts of thework to the next operator.If all of these improvements are implemented, we expect a set-up time reductionof 20.5% which corresponds to about 35min per set-up. By ignoring the runningtime and only check on the setup times, one can see an improvement of 36.4%.

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    Ställtidsoptimering
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    Bilagor
  • 326.
    Bessiere, Christian
    et al.
    CNRS, University of Montpellier, France.
    De Raedt, Luc
    DTAI, KU Leuven, Belgium.
    Guns, Tias
    DTAI, KU Leuven, Belgium.
    Kotthoff, Lars
    University of Wyoming, Wyoming, USA.
    Nanni, Mirco
    ISTI-CNR, France.
    Nijssen, Siegfried
    DTAI, KU Leuven, Belgium.
    O’Sullivan, Barry
    Insight, University College Cork, Ireland.
    Paparrizou, Anastasia
    CNRS, France.
    Pedreschi, Dino
    University of Pisa, Italy.
    Simonis, Helmut
    Insight, University College Cork, Ireland.
    The Inductive Constraint Programming Loop2017In: IEEE Intelligent Systems, ISSN 1541-1672, E-ISSN 1941-1294, Vol. 32, no 5, p. 44-52Article in journal (Refereed)
    Abstract [en]

    Constraint programming is used for a variety of real-world optimisation problems, such as planning, scheduling and resource allocation problems. At the same time, one continuously gathers vast amounts of data about these problems. Current constraint programming software does not exploit such data to update schedules, resources and plans. We propose a new framework, that we call the Inductive Constraint Programming loop. In this approach data is gathered and analyzed systematically, in order to dynamically revise and adapt constraints and optimization criteria. Inductive Constraint Programming aims at bridging the gap between the areas of data mining and machine learning on the one hand, and constraint programming on the other hand.

  • 327.
    Bhatt, Mehul
    et al.
    Örebro University, School of Science and Technology. University of Bremen, Bremen, Germany.
    Lewis, Clayton
    University of Colorado, Boulder, USA.
    Multimodality in Embodied Experience Design: Workshop at INTERACT 2017, Mumbai, INDIA2017In: Human-Computer Interaction – INTERACT 2017, Part IV, Springer, 2017, Vol. LNCS-10516, p. 533-534Conference paper (Refereed)
    Abstract [en]

    The workshop on Multimodality in Embodied Experience Design addresses the role of multimodality and mediated interaction for the analysis and design of human-centred, embodied, cognitive user experiences. Research topics being addressed encompass formal, computational, cognitive, design, engineering, empirical, and philosophical perspectives at the interface of artificial intelligence, cognitive science, and interaction design.

  • 328.
    Bhattacharyya, Subhajit
    et al.
    ECE Department, Mallabhum Institute of Technology, West Bengal, India.
    Chakraborty, Subham
    CSE Department, Mallabhum Institute of Technology, West Bengal, India.
    Reconstruction of Human Faces from Its Eigenfaces2014In: International Journal of Advanced Research In Computer Science and Software Engineering, ISSN 2277-6451, E-ISSN 2277-128X, Vol. 4, no 1, p. 209-215Article in journal (Refereed)
    Abstract [en]

    Eigenface or Principal Components Analysis (PCA) methods have demonstrated their success in face recognition, detection and tracking. In this paper we have used this concept to reconstruct or represent a face as a linear combination of a set of basis images. The basis images are nothing but the eigenfaces. The idea is similar to represent a signal in the form of a linear combination of complex sinusoids called the Fourier Series. The main advantage is that the number of eigenfaces required is less than the number of face images in the database. Selection of number of eigefaces is important here. Here we investigate what is the number of minimum eigenface that is required for faithful production of a face image.

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    Reconstruction of Human Faces from Its Eigenfaces
  • 329.
    Bhattacharyya, Subhajit
    et al.
    Mallabhum Institute of Technology, Bishnupur, West Bengal, India.
    Chand, Nisarga
    Mallabhum Institute of Technology, Bishnupur, West Bengal, India.
    Chakraborty, Subham
    Mallabhum Institute of Technology, Bishnupur, West Bengal, India.
    A Modified Encryption Technique using Playfair Cipher 10 by 9 Matrix with Six Iteration Steps2014In: International Journal of Advanced Research in Computer Engineering & Technology, ISSN 2278-1323, Vol. 3, no 2, p. 307-312Article in journal (Refereed)
    Abstract [en]

    One of the well-known digraph substitution cipher is the Playfair Cipher. It secures information mathematically by mangling message with key. The privacy of intended sender and receiver information is protected from eavesdropper. However the original 5 x 5 Playfair Cipher can support only 25 uppercase alphabets. Here we have implemented a new technique which includes a rectangular matrix having 10 columns and 9 rows and six iteration steps for encryption as well as decryption purpose. This 10 x 9 rectangular matrix includes all alphanumeric characters and some special characters. Cryptanalysis is done to show that the modified cipher is a strong one. Finally we have implemented this concept with the help of MATLAB.

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    A modified encryption technique using Playfair cipher 10 by 9 matrix with six iteration steps
  • 330.
    Billah, Mohammad Ehtasham
    et al.
    School of Business, Örebro University, Örebro, Sweden.
    Javed, Farrukh
    Örebro University, Örebro University School of Business.
    Bayesian Convolutional Neural Network-based Models for Diagnosis of Blood Cancer2022In: Applied Artificial Intelligence, ISSN 0883-9514, E-ISSN 1087-6545, Vol. 36, no 1Article in journal (Refereed)
    Abstract [en]

    Deep learning methods allow computational models involving multiple processing layers to discover intricate structures in data sets. Classifying an image is one such problem where these methods are found to be very useful. Although different approaches have been proposed in the literature, this paper illustrates a successful implementation of the Bayesian Convolution Neural Networks (BCNN)-based classification procedure to classify microscopic images of blood samples (lymphocyte cells) without involving manual feature extractions. The data set contains 260 microscopic images of cancerous and noncancerous lymphocyte cells. We experiment with different network structures and obtain the model that returns the lowest error rate in classifying the images. Our developed models not only produce high accuracy in classifying cancerous and noncancerous lymphocyte cells but also provide useful information regarding uncertainty in predictions.

  • 331.
    Bimer, Hampus
    et al.
    Örebro University, School of Science and Technology.
    Stenmark, Jonas
    Örebro University, School of Science and Technology.
    Optimering av produktionslinje för att reducera ledtiden: En fallstudie på Seco Tools AB i Arboga2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This case study has been carried out at the Seco Tools factory in Arboga. Seco Tools is one of the world's largest providers of comprehensive metal cutting solutions for milling, turning, holemaking and tooling systems. The majority of the Arboga factory are at the front edge with continuous improvements. However, since a time back problems have occurred with one of their manufacturing lines. The problem that Seco Tools considers to have with the line is the long lead time and the current layout is far from optimal.

    The purpose of this case study was to make a mapping of the process and then analyze and make suggestions on how the process could be more effective with considerations of reducing lead time. The proposals have been made by empirical data collection through interviews with employees as well as observations in production. The information obtained has been studied and analyzed using several theories and tools, and thereafter suggestions have been made for improvements. Five proposals for different alternative layouts have been made, but also more general improvement proposals have been put forward to accomplish a positive impact on the lead time of the process. These proposals will serve as a supporting basis for Seco Tools in their continued efforts to improve the process.

  • 332. Birk, Andreas
    et al.
    Poppinga, Jann
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Nevatia, Yashodhan
    Planetary Exploration in USARSim: A Case Study including Real World Data from Mars2009In: RoboCup 2008: Robot Soccer World Cup XII / [ed] Volume editors: Luca Iocchi, Hitoshi Matsubara, Alfredo Weitzenfeld, Changjiu Zhou, Springer Berlin Heidelberg , 2009, p. 463-472Conference paper (Refereed)
    Abstract [en]

     Intelligent Mobile Robots are increasingly used in unstructured domains; one particularly challenging example for this is, planetary exploration. The preparation of according missions is highly non-trivial, especially as it is difficult to carry out realistic experiments without, very sophisticated infrastructures. In this paper, we argue that, the, Unified System for Automation and Robot Simulation (USARSim) offers interesting opportunities for research on planetary exploration by mobile robots. With the example of work on terrain classification, it, is shown how synthetic as well as real world data, from Mars call be used to test an algorithm's performance in USARSim. Concretely, experiments with an algorithm for the detection of negotiable ground oil a, planetary surface are presented. It is shown that the approach performs fast; and robust on planetary surfaces.

  • 333. Birk, Andreas
    et al.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Nevatia, Yashodhan
    Ambrus, Rares
    Poppinga, Jan
    Pathak, Kaustubh
    Terrain Classification for Autonomous Robot Mobility: from Safety, Security Rescue Robotics to Planetary Exploration2008Conference paper (Refereed)
  • 334.
    Birkelöf, Jonas
    Örebro University, School of Science and Technology.
    Framtagning av demonstratorer2009Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    På Alfred Nobelmuseet i Karlskoga finns en avdelning som kallas Fiffiga huset. Där finns många experiment som besökare kan prova på, samt montrar som visar hur olika tekniska och maskinella apparater fungerar. Till utställningen och öppnandet sommaren 2009 ville de ha två nya demonstratorer. I rapporten kallas dem för reaktionstidsväggen och baklängesprataren. Reaktionstidsväggen skulle mäta besökarens reaktionstid genom att tryckknappar, med inbyggda dioder som slumpvis tänds, trycks ned i rätt ordning. Baklängesprataren skulle spela in besökarens tal och sedan spela upp det baklänges. Tanken var att besökaren skulle försöka prata baklänges och få det att låta rätt vid uppspelning. Arbetet gick ut på att bygga dessa demonstratorer och montera dem i Fiffiga huset. Reaktionstidsväggen styrdes med hjälp av en mikroprocessor ATMega16 från Atmel. Dess jobb var att läsa av knapptryckningar samt skicka information till dioder och display. Även baklängesprataren skulle styras med hjälp av mikroprocessorn ATMega16. En enkel mikrofonförstärkare samt filter till högtalarna skulle anslutas till processorn. Det inbyggda minnet skulle inte räcka till så ett extern minne behövde anslutas.Endast reaktionstidsväggen hann bli färdig inom projektets ramar eftersom all gammal elektronik som medföljde från Nobelmuseet var komplex, samt att många kortslutningar och avbrott gjorde felsökning till en tidskrävande procedur.

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    FULLTEXT01
  • 335.
    Bjuhr, Jessica
    et al.
    Örebro University, School of Science and Technology.
    Jansson, Maria
    Örebro University, School of Science and Technology.
    Förstudie kring verktyg för DCN registrering/uppföljning2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis work has been performed on a department that works with preparation for new products. They are in charge of coordinating several different units during these preparations. In the current situation, this process does not work optimally. There is no common approach to monitoring and documentation of the process which leads to difficulties in the interaction between the units. Problems have also arisen when the product has been put into production. The company is also working with the ISO 9001 and 14001, which requires documentation and monitoring of the process.

    The aim of the project is to present the basic steps for a new approach for documentation and monitoring in this process from a case study. Interviews with employees in the process have been conducted to gather information about the current approach. In addition, literary studies and benchmarking have been used as methods.

    Based on this, improvement proposals for the work of documentation and monitoring have been developed. The proposals may also contribute to increased understanding of the process and improved collaboration between the employees. However, this is not something that can be guaranteed. The improvement proposals should be seen just as a suggestion for improvement and not hindsight on how the work should be designed in the process.

  • 336.
    Björkegren, Joakim
    et al.
    Örebro University, School of Science and Technology.
    Stenberg, Björn
    Örebro University, School of Science and Technology.
    Utveckling av drivmekanism för automatiserad paletthantering2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is a development project that deals with the transmission mechanism of pallets in robotic welding systems.

    Details to be welded are mounted on pallets. These are automatically transferred from a roller table to a workpiece positioner, holding the pallet in place during welding. The difficulty is due to the limited movements of the workpiece positioner. It is not always known what the customer wants to mount on the pallet. This limits the space available for the drive mechanism. The current system is built into the workpiece positioner. Increased competition has driven the need to reduce cost of the robotic welding systems. The drive mechanism for the pallets is an area where the company believes that costs can be cut.

    The report includes an idea generating process, development and simulation of a proposed solution to a design that replaces the current solution. The results section presents a solution proposal in the form of a conveyor which replaces both the current drive mechanism and one of the roller tables. Cost estimation is presented where the proposed solution is compared to today's solution.

  • 337.
    Björkman, Ludvig
    et al.
    Örebro University, School of Science and Technology.
    Eriksson, Rikard
    Örebro University, School of Science and Technology.
    Flödeseffektivisering av kantpressade artiklar2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Volvo Construction Equipment in Hallsberg manufactures tanks and cabs for wheel loaders, dump trucks, rollers and excavators. This work focuses on the processes of press brake and welding in the production flow of tanks. The production today includes 20 different tank models that are made of 100 press braked articles. In the autumn of 2021 the production will increase with 5 new tank models and 25 press braked articles. The inventory before welding is already highly utilized and won’t be expanded, that’s where Volvo CE has noticed a problem. The schedules that the operators of the press brake and welding operates by are taken from a preliminary annual schedule from Volvo CE's system by SAP. The welding schedule is equalized every week and adapted according to the needs of the internal painting. At the same time the press brake works according to the preliminary annual schedule due to the system having a freezing time between press brake and welding. This creates an imbalance and prevents the press brake schedule from levelling. The processes for press braking, internal transport and welding don't have standardizations, which entail that the organization doesn't have control of the flow. 

    he work presents improvement in three parts. The first one is that the freezing time between press brake and welding should be eliminated, to make the flow balanced. It is proposed that standards should be introduced in every process in the flow. It would ensure the process and make it generate the same output every time regardless of the operator. Standardisation supports sustainability on the social side because co-workers can feel that they can complete things that the organisation wants. New set-up times, cycle times and process efficiency can then be calculated, which is required for the schedule to be levelled and optimized. The balanced and leveled flow in combination with the introduced method standards will lead to a reduced lead time, which entails a reduced storage time. This will favour the economic growth for Volvo CE and reduce the amount of restricted capital. 

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    fulltext
  • 338.
    Björtoft, David
    et al.
    Örebro University, School of Science and Technology.
    Eneqvist, Adam
    Örebro University, School of Science and Technology.
    Profillagerhantering med lagerhiss: en studie för att skapa ett användarvänligt lager på MaxiDoor AB: Profile storage management with a vertical storage lift:  a study to create a user-friendly storage at MaxiDoor AB2020Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    MaxiDoor AB designs and manufacture steel doors and steel segments to specific customer order and are specialist on solutions where high security is requested. The company seeks to expand during the coming years and have launched an investment plan to adapt the production for higher turnover.  This work intends to look over and improve todays material supply in terms of steel profiles with the basis that expected turnover for the production unit ES will grow from 100 mkr to 145 mkr and in addition the company wishes to keep a one-piece production. This will be solved with the help of, among other things, a vertical storage lift. In parallel with the expected increase in rate of production, the supply of materials must also be developed to meet future demand. Based on theory and analysis of the current situation, it is found that the storage design quickly becomes complex with the existing conditions. The final recommendation of the study is to divide the storage into three sections; a vertical storage lift, a coarse buffer and a fine buffer. This results in a user-friendly material supply that is expected to be sustainable in the long term. The vertical storage lift is intended to store orders with planned and dedicated consumption as well as other profiles and residual profiles. In this way, the elevator acts as both storage and buffer. The coarse buffer and fine buffer are used according to a funnel principle where orders are broken down into individual profiles to be cut. Finally, various aspects are discussed regarding the supply of materials and future work.

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    Profillagerhantering med lagerhiss: en studie för att skapa ett användarvänligt lager på
  • 339.
    Blad, Samuel
    et al.
    Örebro University, School of Science and Technology. Nexer.
    Längkvist, Martin
    Örebro University, School of Science and Technology.
    Klügl, Franziska
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Empirical analysis of the convergence of Double DQN in relation to reward sparsity2022In: 21st IEEE International Conference on Machine Learning and Applications. ICMLA 2022: Proceedings / [ed] Wani, MA; Kantardzic, M; Palade, V; Neagu, D; Yang, L; Chan, KY, IEEE, 2022, p. 591-596Conference paper (Refereed)
    Abstract [en]

    Q-Networks are used in Reinforcement Learning to model the expected return from every action at a given state. When training Q-Networks, external reward signals are propagated to the previously performed actions leading up to each reward. If many actions are required before experiencing a reward, the reward signal is distributed across all those actions, where some actions may have greater impact on the reward than others. As the number of significant actions between rewards increases, the relative importance of each action decreases. If actions have too small importance, their impact might be over-shadowed by noise in a deep neural network model, potentially causing convergence issues. In this work, we empirically test the limits of increasing the number of actions leading up to a reward in a simple grid-world environment. We show in our experiments that even though the training error surpasses the reward signal attributed to each action, the model is still able to learn a smooth enough value representation.

  • 340.
    Blomqvist, Edith
    et al.
    Örebro University, School of Science and Technology.
    Dahlgren, Katarina
    Örebro University, School of Science and Technology.
    Konceptframtagning av kontorsmöbel2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report describes the product development of office furniture. The thesis was executed within the engineering program of industrial design and product development at Örebro University.

    The project was an assignment from the company Nitton93. The firm is based in Örebro and provides store interior. After inquiry from their customers the firm started the development of a line of office furniture. Office furniture has looked basically the same for many years and Nitton93 wanted to change that through creating a line of office furniture for the future. The assignment was to develop a storage furniture for an office environment.

    This project began with pre-study containing information gathering of existing solutions, working environment, safety, ergonomics and use. After the pre-study an analysis was executed and from these two the demands and requests on the final product was set. Ideas were found in the phase of generating concept with the help of different methods and tools. Four concepts were chosen from these ideas and later evaluated.

    The chosen concept was developed further and the result was a storage furniture fitted for open offices. The size of the unit contributes to screening and lots of storage. The screening and the design of the furniture contributes to a calm working environment.

    The project extended to concept development, therefore the next step for the outsourcer was to produce production data. This thesis is well worked through and should form a good foundation for continued work with production and sale.

  • 341.
    Blomqvist, Emil
    Örebro University, School of Science and Technology.
    Konstruktion av lyftredskap2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report consists of the mechanical design of a lifting tool. The project was commissioned by ELE Engineering AB and carried out as part of the bachelor’s program in Mechanical engineering on Örebro University.

    ELE Engineering AB has received a request from a client to design a lifting tool that will remove the need for manual lifting of one of their components, the component is cylindrical and come in various sizes. This lifting tool need to be completely mechanical and adjustable by hand. The project was divided into separate stages in a similar way to the projects done previously in the university program. It starts with generating design concepts and then working its way to the producing of manufacturing plans and drawings.

    The result is a lifting tool that fulfils all the requirements and standards, only a handful of work is left until the project is lifting tool is completed and ready for manufacturing. These are to produce instructions for operation and maintenance to fulfil the requirements for CE marking, fabrication of a prototype for test lifting and a detailed cost analysis. The lifting tool consists of a beam onto which a lifting hook and a threaded rod is mounted. The threaded rod creates a sideways motion for two connected lifting arms when rotated and thus enabling adjustments to be made.

  • 342.
    Blomqvist, Eva
    et al.
    Linköping University, Linköping, Sweden.
    Alirezaie, Marjan
    Örebro University, School of Science and Technology.
    Santini, Marina
    RISE, Research Institutes of Sweden.
    Towards Causal Knowledge Graphs - Position Paper2020In: Proceedings of the 5th International Workshop on Knowledge Discovery in Healthcare Data co-located with 24th European Conference on Artificial Intelligence (ECAI 2020) / [ed] Kerstin Bach, Razvan Bunescu, Cindy Marling, Nirmalie Wiratunga, Technical University of Aachen , 2020, Vol. 2675, p. 58-62Conference paper (Refereed)
    Abstract [en]

    In this position paper, we highlight that being able to analyse the cause-effect relationships for determining the causal status among a set of events is an essential requirement in many contexts and argue that cannot be overlooked when building systems targeting real-world use cases. This is especially true for medical contexts where the understanding of the cause(s) of a symptom, or observation, is of vital importance. However, most approaches purely based on Machine Learning (ML) do not explicitly represent and reason with causal relations, and may therefore mistake correlation for causation. In the paper, we therefore argue for an approach to extract causal relations from text, and represent them in the form of Knowledge Graphs (KG), to empower downstream ML applications, or AI systems in general, with the ability to distinguish correlation from causation and reason with causality in an explicit manner. So far, the bottlenecks in KG creation have been scalability and accuracy of automated methods, hence, we argue that two novel features are required from methods for addressing these challenges, i.e. (i) the use of Knowledge Patterns to guide the KG generation process towards a certain resulting knowledge structure, and (ii) the use of a semantic referee to automatically curate the extracted knowledge. We claim that this will be an important step forward for supporting interpretable AI systems, and integrating ML and knowledge representation approaches, such as KGs, which should also generalise well to other types of relations, apart from causality.

  • 343.
    Blomqvist, J.
    et al.
    Department of Microbiology, Uppsala Biocenter, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    South, E.
    Department of Microbiology, Uppsala Biocenter, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Tiukova, L.
    Department of Microbiology, Uppsala Biocenter, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Momeni, M. H.
    Department of Molecular Biology, Uppsala Biocenter, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Hansson, H.
    Department of Molecular Biology, Uppsala Biocenter, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Ståhlberg, J.
    Department of Molecular Biology, Uppsala Biocenter, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Horn, S. J.
    Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, Norway.
    Schnürer, Johan
    Department of Microbiology, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden.
    Passoth, V.
    Department of Microbiology, Uppsala Biocenter, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Fermentation of lignocellulosic hydrolysate by the alternative industrial ethanol yeast Dekkera bruxellensis2011In: Letters in Applied Microbiology, ISSN 0266-8254, E-ISSN 1472-765X, Vol. 53, no 1, p. 73-78Article in journal (Refereed)
    Abstract [en]

    Aim: Testing the ability of the alternative ethanol production yeast Dekkera bruxellensis to produce ethanol from lignocellulose hydrolysate and comparing it to Saccharomyces cerevisiae.

    Methods and Results: Industrial isolates of D. bruxellensis and S. cerevisiae were cultivated in small-scale batch fermentations of enzymatically hydrolysed steam exploded aspen sawdust. Different dilutions of hydrolysate were tested. None of the yeasts grew in undiluted or 1 : 2 diluted hydrolysate [final glucose concentration always adjusted to 40 g l(-1) (0.22 mol l(-1))]. This was most likely due to the presence of inhibitors such as acetate or furfural. In 1 : 5 hydrolysate, S. cerevisiae grew, but not D. bruxellensis, and in 1 : 10 hydrolysate, both yeasts grew. An external vitamin source (e.g. yeast extract) was essential for growth of D. bruxellensis in this lignocellulosic hydrolysate and strongly stimulated S. cerevisiae growth and ethanol production. Ethanol yields of 0 42 +/- 0 01 g ethanol (g glucose)(-1) were observed for both yeasts in 1 : 10 hydrolysate. In small-scale continuous cultures with cell recirculation, with a gradual increase in the hydrolysate concentration, D. bruxellensis was able to grow in 1 : 5 hydrolysate. In bioreactor experiments with cell recirculation, hydrolysate contents were increased up to 1 : 2 hydrolysate, without significant losses in ethanol yields for both yeasts and only slight differences in viable cell counts, indicating an ability of both yeasts to adapt to toxic compounds in the hydrolysate.

    Conclusions: Dekkera bruxellensis and S. cerevisiae have a similar potential to ferment lignocellulose hydrolysate to ethanol and to adapt to fermentation inhibitors in the hydrolysate.

    Significance and Impact of the study: This is the first study investigating the potential of D. bruxellensis to ferment lignocellulosic hydrolysate. Its high competitiveness in industrial fermentations makes D. bruxellensis an interesting alternative for ethanol production from those substrates.

  • 344.
    Blomqvist, Johanna
    et al.
    Department of Microbiology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Eberhard, Thomas
    Department of Microbiology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Schnürer, Johan
    Department of Microbiology, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden.
    Passoth, Volkmar
    Department of Microbiology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Fermentation characteristics of Dekkera bruxellensis strains2010In: Applied Microbiology and Biotechnology, ISSN 0175-7598, E-ISSN 1432-0614, Vol. 87, no 4, p. 1487-1497Article in journal (Refereed)
    Abstract [en]

    The influence of pH, temperature and carbon source (glucose and maltose) on growth rate and ethanol yield of Dekkera bruxellensis was investigated using a full-factorial design. Growth rate and ethanol yield were lower on maltose than on glucose. In controlled oxygen-limited batch cultivations, the ethanol yield of the different combinations varied from 0.42 to 0.45 g (g glucose)(-1) and growth rates varied from 0.037 to 0.050 h(-1). The effect of temperature on growth rate and ethanol yield was negligible. It was not possible to model neither growth rate nor ethanol yield from the full-factorial design, as only marginal differences were observed in the conditions tested. When comparing three D. bruxellensis strains and two industrial isolates of Saccharomyces cerevisiae, S. cerevisiae grew five times faster, but the ethanol yields were 0-13% lower. The glycerol yields of S. cerevisiae strains were up to six-fold higher compared to D. bruxellensis, and the biomass yields reached only 72-84% of D. bruxellensis. Our results demonstrate that D. bruxellensis is robust to large changes in pH and temperature and may have a more energy-efficient metabolism under oxygen limitation than S. cerevisiae.

  • 345.
    Blume, Stuart
    et al.
    Univ Amsterdam, Amsterdam, Netherlands.
    Galis, Vasilis
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Pineda, Andres Valderrama
    Introduction: STS and Disability2014In: Science, Technology and Human Values, ISSN 0162-2439, E-ISSN 1552-8251, Vol. 39, no 1, p. 98-104Article in journal (Refereed)
    Abstract [en]

    What is the conventional sense of disability, and how do the questions addressed in this special issue of Science, Technology, & Human Values (STHV) differ from those inspired by Donna Haraway and the cyborg? In industrialized societies, the medical profession has authority over the determination of who should count as disabled while assistive technologies enable specific kinds of subject positions (in terms of personhood and competencies as well as limits). In this special issue of STHV, the focus of the essays as a whole is on the different enactments of disability, as complexity that simultaneously implicates bodies, gender, sexuality, technology, and politics. The study of disability offers scope for refinement and further articulation of many issues of long-standing concern to science, technology, and society (STS). In addition, we hope they will encourage further reflection on our field's normative engagement.

  • 346.
    Bodin, Tomas
    Örebro University, School of Science and Technology.
    Dimensionering av två olika typer av träbroar2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I denna rapport dimensioneras två olika träbroar efter Eurokoderna. En med underspänning och en utan. Syftet var att jämföra konstruktionstyperna. Hjälpmedel för att åstadkomma detta var beräkningsprogrammet Rstab och Mathcad. Resultatet visade att vibrationer spelar en stor roll vid dimensioneringen. Plattan utan underspänning behövde vara två och en halv gånger så hög som den med underspänning för att klara vibrationskraven. Vilket medförde att den fick en låg utnyttjandegrad rörande hållfasthet. För bron med underspänning blev både hållfastheten och vibrationerna i stort sett lika avgörande vid dimensionering.

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  • 347.
    Bodur, Sara
    et al.
    Örebro University, School of Science and Technology.
    Billinger, Petter
    Örebro University, School of Science and Technology.
    Design av AerosolTraps applikationshölje - Arbetsprocessen2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    AerosolTrap AB has developed a filter-free system for particle separation in different flows like fluids and gases. This patented product is suitable for a variety of environments depending on the purpose. For example, the restaurant environment in which this application is called the "grease trap". This thesis is based on the design process needed to develop a casing for the restaurant application that shortly will be installed in the Scandic Grand Hotel kitchen in Örebro.

     

    The process includes a feasibility study in forms of interviews and basic research, as well as brainstorming and concept evaluation. Meetings were arranged with supervisors at the university and the AerosolTrap office to obtain constant feedback on our achievements. During the final phase of the project the opportunity to visit the Scandic Grand Hotel's restaurant kitchen was given. Thus an investigation could be done on whether any changes were needed before the final concept. Hand sketches, CAD models and edited images were used throughout the project to simply illustrate the esthetics, functions and materials.

     

    The result is consistent with the given requirements, and as a concept it leaves room for further development and adaptation.

  • 348.
    Boman, Benjamin
    Örebro University, School of Science and Technology.
    Effektivisering av slutflöde linjetillverkning av lastbilshytter2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Laxå Special Vehicles also called LSV was started in 1962 and since 2021 is a wholly owned subsidiary of Scania that builds Scania's special vehicles. The company builds both chassis and cabs; however, this work is limited to cab production and, more specifically, final assembly of the cabs. The final assembly of cabs is the end flow it contains six stations, where five och the stations are manual assembly and the sixth one is an oven where the cabs are hardened. LSV have had problems with the end flow not completing the eight cabs a day that are planned; therefore, this work investigates how it is possible to streamline the end flow so that they reach the planned goal. The goal of the work is to present improvement proposals that could increase the efficiency of the final flow. In order to investigate what opportunities for improvement exist, work begins with looking at the root causes that can cause the low efficiency. Tools used to look at this are partly a flow analysis that looks at one of the products that are produced, but also Lean tools such as Spaghetti diagrams, Ishikawa diagrams and 5-whys are used to determine potential root causes of the problem. The results of the work lead to the following conclusions: that the company should continue to work with 5S, that the company should make itself less dependent on the forklift in the final flow by removing physical obstacles that today mean that a forklift needs to be used to move cabs and that the company should work towards securing its personnel supply in the final flow either by training personnel within the company who work with less time-pressured tasks or alternatively work with staffing companies so that there is an opportunity to bring in temporary workers via staffing companies.

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  • 349.
    Bonaccorsi, Manuele
    et al.
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Fiorini, Laura
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Cavallo, Filippo
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Dario, Paolo
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    A cloud robotics solution to improve social assistive robots for active and healthy aging2016In: International Journal of Social Robotics, ISSN 1875-4791, E-ISSN 1875-4805, Vol. 8, no 3, p. 393-408Article in journal (Refereed)
    Abstract [en]

    Technological innovation in robotics and ICT represents an effective solution to tackle the challenge of providing social sustainable care services for the ageing population. The recent introduction of cloud technologies is opening new opportunities for the provisioning of advanced robotic services based on the cooperation of a number of connected robots, smart environments and devices improved by the huge cloud computational and storage capability. In this context, this paper aims to investigate and assess the potentialities of a cloud robotic system for the provisioning of assistive services for the promotion of active and healthy ageing. The system comprised two different smart environments, located in Italy and Sweden, where a service robot is connected to a cloud platform for the provisioning of localization based services to the users. The cloud robotic services were tested in the two realistic environments to assess the general feasibility of the solution and demonstrate the ability to provide assistive location based services in a multiple environment framework. The results confirmed the validity of the solution but also suggested a deeper investigation on the dependability of the communication technologies adopted in such kind of systems.

  • 350.
    Bondarenko, N.
    et al.
    Division of Materials Theory, Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden.
    Chico, J.
    Division of Materials Theory, Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden; Peter Grünberg Institut and Institute of Advanced Simulation, Forschungszentrum Jülich & JARA, Jülich, Germany .
    Kvashnin, Y. O.
    Division of Materials Theory, Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden.
    Bergman, A.
    Division of Materials Theory, Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden; Maison de la Simulation, USR 3441, CEA-CNRS-INRIA-Université Paris-Sud-Université de Versailles, Gif-sur-Yvette, France; L_Sim, INAC-MEM, CEA, Grenoble, France.
    Skorodumova, N. , V
    Division of Materials Theory, Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden; Multiscale Materials Modelling, Department of Materials Science and Engineering, Royal Institute of Technology, Stockholm, Sweden.
    Eriksson, Olle
    Örebro University, School of Science and Technology. Division of Materials Theory, Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden.
    Spin polaronics: Static and dynamic properties of spin polarons in La-doped CaMnO42019In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 100, no 13, article id 134443Article in journal (Refereed)
    Abstract [en]

    The static and dynamic properties of spin polarons in La-doped CaMnO3 are explored theoretically, by means of an effective low-energy Hamiltonian. All parameters of the effective Hamiltonian are evaluated from first-principles theory. The Hamiltonian is used to investigate the temperature stability as well as the response to an external applied electric field, for spin polarons in bulk, surface, and as single two-dimensional layers. Technically this involves atomistic spin-dynamics simulations in combination with kinetic Monte Carlo simulations. Where a comparison can be made, our simulations exhibit excellent agreement with available experimental data and previous theory. Remarkably, we find that excellent control of the mobility of spin polarons in this material can be achieved, and that the critical parameters deciding this are the temperature and strength of the applied electrical field. We outline different technological implications of spin polarons, and point to spin polaronics as an emerging subfield of nanotechnology. In particular, we demonstrate that it is feasible to write and erase information on an atomic scale, by use of spin polarons in CaMnO3.

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