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  • 251.
    Bach, Dennis
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Konceptframtagning för vinkelväxel: En studie på tätningsmekanism och utformning för att undvika oljeläckage2018Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This project is part of the examination in the education bachelor’s degree in innovation technology and design. The assignment is provided by GKN Driveline Köping AB. GKN Driveline is global leading with their AWD system and is in a constant development. Challenges which they are aware of, to minimize environmental impact by constantly reducing weight and power loss on their power take of units. And at the same time to consider lowering the development cost and short lead times. Which has led to detection during tests with problems such as oil leakage between the split plane of the housing and cover. GKN wish to consider a solution to prevent this event to happen during an early design phase, thus provide higher quality, customer satisfaction and less impact on the environment. The purpose of this project is to identify the factors that affect oil leakage at the split plane between housing and cover in power transfer units and find a solution to prevent this. The goal is to use the design process to contribute to a concept that will give rise to a basis of new development of power transfer units. The milestone in the project is to illustrate and describe the chosen concept with its pros and cons as well as aspects that affect oil leakage. Methods covered in the project include project planning, pilot study, product specification, generating-, evaluating and developing the concept. This resulted in a concept that illustrates its advantage with the freedom to design the split plane. This delivered concept is a basis for continued development and optimization to be a fully functional product in the future.

  • 252. Backfolk, K.
    et al.
    Johansson, Caisa
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre.
    Peltonen, J.
    Association between a sodium salt of a linear dodecylbenzene sulphonate and a non-ionic fatty alcohol ethoxylate surfactant during film formation of styrene/butadiene latex2006In: Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2006, 291 (1-3), 38-44Article in journal (Refereed)
  • 253.
    Backman, Carl
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Lindefelt, Daniel
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Mångfaldens Jakobsberg: En plats för alla2012Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
  • 254.
    Backram, Emil
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Programmering av testrigg för marindrivlina2014Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Marinediesel Sweden AB in Ängelholm manufacture and develop marine engines and stern drives. Idid my thesis at the company division MD Engineering that is specialized in marine powertrainresearch and development.Marinediesel Sweden AB in Ängelholm were in need of a control program for a test rig they built inorder to test their sterndrives. This thesis report describes the process to optimize and finish a test rigfor marine powertrains. In this report I discuss how the test rig is constructed, it's operation and theissues I encountered along the way. Among other things, I describe how the power loss is calculatedby the energy difference of the supplied and abducted oil in the gear, and how the applied torque,which simulates the load at actual operating conditions, are controlled and calculated using only thepressure in the hydraulic cylinders.

  • 255.
    Bader, Thomas K.
    et al.
    Linnéuniversitetet, Institutionen för byggteknik (BY).
    Vessby, Johan
    Linnéuniversitetet, Institutionen för byggteknik (BY).
    Modeling displacement path dependence in nailed sheathing-to-framing connections2017In: CompWood 2017 - Computational Methods in Wood Mechanics - from Material Properties to Timber Structures: Programme & Books of Abstracs / [ed] Josef Füssl, Thomas K. Bader, Josef Eberhardsteiner, Vienna: TU verlag , 2017Conference paper (Refereed)
  • 256.
    Bader, Thomas K.
    et al.
    Linnéuniversitetet, Institutionen för byggteknik (BY).
    Vessby, Johan
    Linnéuniversitetet, Institutionen för byggteknik (BY).
    Enquist, Bertil
    Linnéuniversitetet, Institutionen för byggteknik (BY).
    Path dependence in OSB sheathing-to-framing nailed connection revealed by biaxial testing2018In: Journal of Structural Engineering, ISSN 0733-9445, E-ISSN 1943-541X, Vol. 144, no 10, article id 04018197Article in journal (Refereed)
    Abstract [en]

    OSB sheathing-to-wood framing connection, as typically used in light-frame shear walls, was experimentally examined in a novel biaxial test setup with respect to possible path dependence of the load-displacement relation. The connection with an annular-ringed shank nail was loaded under displacement control following nine different displacement paths within the sheathing plane, which coincided at a number of points. In intersection points, resultant connection force, its orientation and work performed on the connection system to reach the specific point were calculated and compared. Evaluation of experiments revealed significant path dependence with respect to orientation of force resultants at path intersection points. However, magnitude of the forces and the work carried out showed relatively small dependence of the displacement path undertaken. Comparison of uniaxial connection tests with the European yield model demonstrated strong contribution of withdrawal resistance of the ringed shank nail to its lateral strength. Results of this type are a valuable basis to build better models when simulating such connections in wood structures.

  • 257.
    Badran, Mona
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Zetterlind, Stina
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Fel i byggskedet som kan härledas till projekteringen2013Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Errors that occur in a construction project often leads to overspending and a flawless project is next to impossible to achieve. However, one can try to reduce the risk of errors through good planning. Planning phase of a construction project is a very important part of the project, that's where you get into the construction project will be undertaken.

    Typically, it is unclear where the errors start but in the analyzes made by the Swedish Construction Federation, R-West and Chalmers during 1994-1996 has shown that errors often have their roots already in the start of the clients, designers, material suppliers and providers. Is there an error in the beginning, it is clear throughout the process, the designer does not check whether the architect or designer has done wrong, but based just on. (Josephson and Hammarlund 1996). In the design stage plan how the construction should be carried out in as much detail as possible. You see that everything works drawing wise so that everything fits as it is often confined spaces.

    The purpose of this report was to determine which wrongs occurs of the construction sites we have visited and why they occur and to recommend what they can do to avoid these mistakes in future projects.

    We have worked with two different contractors, Construction Klason AB in Vimmerby and Peab in Arvika, where we have been following a construction project at the building contractor. We have been out on the projects in which we have tried to observe the defects and also found some through the call. With errors, we believe that it is something that was not as it was planned, a deviation in the planning. It can also be wrong to give a stop or delay of any kind.

    We also found information through literature reports, student literature and articles from the internet. But the result is based mostly on our own observations on the ground and through conversations with various officials.

    The errors that occurred were due to lack of commitment a factor that was great on both projects. It has also emerged that poor communication and preparation for the planning meetings has been something that has contributed to some errors on the construction site, even ignorance, time pressure and unclear requirements have contributed to the failure.

    For a construction project should have as little disruption as possible, you should have plenty of time for planning, scanning and construction. But even good collaboration, communication, and accuracy is important for a construction project to work correctly.

  • 258.
    Bagheri, R.
    et al.
    University of Zanjan, Iran.
    Ayatollahi, M.
    University of Zanjan, Iran.
    Mousavi, Mahmoud
    Aalto University, Finland.
    Analysis of cracked piezoelectric layer with imperfect non-homogeneous orthotropic coating2015In: International Journal of Mechanical Sciences, ISSN 0020-7403, E-ISSN 1879-2162, Vol. 93, p. 93-101Article in journal (Refereed)
    Abstract [en]

    Abstract The fracture problem for a medium composed of a cracked piezoelectric strip with functionally graded orthotropic coating is studied. The layer is subjected to anti-plane mechanical and in-plane electrical loading. In this paper, we first address, the problem of a screw dislocation located in a substrate which is imperfectly bonded to the coating. Then, in order to model the cracked piezoelectric layer, by means of the dislocation solution, we construct integral equations for the layer, in which the unknown variables are dislocation densities. These unknowns are determined through satisfaction of the boundary conditions on the crack faces. By use of the dislocation densities, the field intensity factors are determined. Several examples are presented to demonstrate the applicability of the proposed solution. ", keywords = Piezoelectric strip; Functionally graded layer; Imperfect bonding; Multiple cracks; Stress intensity factors, isbn = 0020-7403, doi=https://doi.org/10.1016/j.ijmecsci.2014.11.025

  • 259.
    Bagheri, R.
    et al.
    University of Zanjan, Iran.
    Ayatollahi, M.
    University of Zanjan, Iran.
    Mousavi, Mahmoud
    Aalto University, Finland.
    Analytical solution of multiple moving cracks in functionally graded piezoelectric strip2015In: Applied mathematics and mechanics, ISSN 0253-4827, E-ISSN 1573-2754, Vol. 36, no 6, p. 777-792Article in journal (Refereed)
    Abstract [en]

    The dynamic behaviors of several moving cracks in a functionally graded piezoelectric (FGP) strip subjected to anti-plane mechanical loading and in-plane electrical loading are investigated. For the first time, the distributed dislocation technique is used to construct the integral equations for FGP materials, in which the unknown variables are the dislocation densities. With the dislocation densities, the field intensity factors are determined. Moreover, the effects of the speed of the crack propagation on the field intensity factors are studied. Several examples are solved, and the numerical results for the stress intensity factor and the electric displacement intensity factor are presented graphically finally.

  • 260.
    Bajracharya, Quree
    Karlstad University, Faculty of Technology and Science.
    Dynamic Modeling, Monitoring and Control of Energy Storage System2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Today there is a great interest on the small scale renewable electricity generation due to the changing economics and the demand for highly sustainable electricity generation. However, renewable energy sources are unreliable and fluctuating which causes variation of power flow. In this situation, there can be server problems such as frequency oscillations, violation of the power line capability jeopardizing the security of the power system. Batteries can be an emerging technology which acts as the fast acting spinning reserve that can balance between the load and generation. Conversely, it very difficult to accurately predict battery performance and the total cost of the investment of storage system by integrating batteries to the renewable system as batteries in this situation have to bear a wide range of the operational conditions . Henceforth, modeling of the battery is extremely important. This master thesis gives the dynamic modeling of the batteries which can replicate the relevant behavior of the battery.

    The proposed methodology is the model based approach where the parameters are determined to develop a suitable model. In this thesis, the battery is modeled as an R-C circuit comprising of elements each of which represents certain battery characteristics. An appropriate model is selected based on the comparative study of the characteristics of experimental output of the battery using model identification. Parameters of the battery are computed in the MATLAB Simulink parameter estimation toolbox using least square estimation .The initial parameter values for the simulink are found with the help of the lab test. Validation results from the two experimental data shows that the model can accurately estimate the battery characteristics with an error of 0.3%.The aforementioned battery model is later used to make an appropriate charge controller.

    The methods used in the thesis performed quite well within the limited tests performed during the experimental works. To use the model online in the future, further investigation is recommended in order to refine the model.

  • 261.
    Baladi, Jibran
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Physics and Electrical Engineering.
    Khan, Naeem ullah
    Karlstad University, Faculty of Technology and Science, Department of Physics and Electrical Engineering.
    Analysis and Reporting of the control tests conducted in connection withcommissioning for control systemupgrade at Ringhals 2.2013Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    This master thesis project was carried out at Ringhals AB Unit 2. It is focused on modeling and introducing a new control strategy for control loop 21414V141/131 which is a condensate water system. Existing control strategy of the selected control loop is simple feedback control system with one PID controller. Results of current control strategy were taken into account for improvements in terms o f system stability, valve movements and unwanted transients. Problems found in selected loop were; large variations in process variable, extra movement in valve positions and inefficient opening of valves.Simulation model with similar control strategy and results as of real power plant was createdand validated, as new control strategy can be applied and results can be compared. The main recommendation to improve the control system performance was found through cascade control strategy that could assist the current controller. The recommendation was evaluated by designing and implementing the cascade control strategy on the Dymola simulation model. Simulation results pointed out considerable increase in system performanceaccording to the requirements of Vattenfall AB.

  • 262. Balderud, Jonas
    Modelling validation and control of the wet-end of a five-layer board machine2003Report (Other academic)
  • 263.
    Balk, Leonard
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Foldable load carrier: Product development and prototyping2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Keywords: Material management, load carrier, product development process, CAD, CAE, CAM

    In this master thesis a foldable load carrier was developed as part of improved material management at AQ Components in Västerås. One of their product lines involves service hatches for trains that are transported within the facility throughout the manufacturing process. Currently, a custom-built load carrier is used to transport the hatches between assembling and painting stations. Unfortunately, the carrier has design and systematic flaws that needs to be resolved. The current carrier is not very protective and occupies a lot of space. The hatches also return from the painting station in an unpredictable order. Before investing in solutions, the subject of material management was studied further. This is a branch within logistics that focus on the internal material flow within industries. Companies that wish to stay competitive continuously invest in improved material management to achieve more profitable material flow, increased capacity, increased regularity and availability, better ergonomics and goods protection. The thesis work followed a classic product development process with focus on a synthesis-analysis loop. After establishing a project plan, the current solution was investigated where the customer need was identified in a product specification. Five concepts were generated and screened, where the most objectively advantageous concept was developed. The new carrier was designed using CAD, in parallel to structural analysis using both CAE and theoretical calculations. The manufacturing process utilizes the sheet metal specialization of AQ Components, where the components were tactically nested using CAM for material efficient laser cutting. Prototyping was carried out before hand over, to ensure the carrier works as well in practise as in theory. The developed load carrier is designed with an outer protective frame, with scratch resistant arms for inserting the service hatches. The frame is foldable with two lockable positions for in and out of use. Once folded, the width is reduced to 1/3rd of the original width. With further safety analysis the carrier can then also be hanged away (with forklift) so that it practically occupies no space at all. The carrier can be transported by forklift in pairs or more, with a total capacity of at least 20 service hatches. The carrier is equipped with an intuitive tracking system, where the carriers and slots are marked. This allows the hatches to return in the order they were sent. The carrier and solution deliver not only on the product specification, but also on the key objectives of improved material management.

  • 264. Bandgren, Johannes
    et al.
    Selberg, Johan
    Twittersentimentanalys: Jämförelse av klassificeringsmodeller tränade på olika datamängder.2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Twitter is one of the most popular microblogs, which is used to express thoughtsand opinions on different topics. An area that has attracted much interest in recentyears is Twitter sentiment analysis. Twitter sentiment analysis is about assessingwhat sentiment a Twitter post expresses, whether it expresses something positiveor negative. Different methods can be used to perform Twitter sentiment analysis.The most common methods of Twitter sentiment analysis use machine learning.The purpose of this study is to evaluate three classification algorithms in ma-chine learning and how the labeling of a data set affects classification models abilityto classify a Twitter post correctly for Twitter sentiment analysis. Naive Bayes,Support Vector Machine and Convolutional Neural Network are the classificationalgorithms that have been evaluated. For each classification algorithm, two classi-fication models have been trained and tested on two separate data sets: StanfordTwitter Sentiment and SemEval. What separates the two data sets, in addition tothe content of the twitter posts, is the labeling method and the amount of twitterposts. The evaluation has been done according to the performance of the classifi-cation models on the respective data sets, training time and how complicated theywere to implement.The results show that all models trained and tested on SemEval achieved ahigher performance than those trained and tested on Stanford Twitter Sentiment.The Convolutional Neural Network models achieved the best results over both datasets. However, a Convolutional Neural Network is more complicated to implementand the training time is significantly longer than Naive Bayes and Support VectorMachine.

  • 265.
    Banell, Mia
    et al.
    Karlstad University, Division for Engineering Sciences, Physics and Mathematics.
    Björfelt, Ulf
    Karlstad University, Division for Engineering Sciences, Physics and Mathematics.
    Svetspåverkan på martensit-austenitiskt rostfritt stål2007Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This thesis is performed at Rolls-Royce AB in Kristinehamn. Rolls-Royce AB is a world leading supplier of different transmission systems for example ship propellers.

    This report contains a material investigation in martensitic-austenitic stainless steel SS EN GX4CrNi13-4 which is used in their propellers.

    The propeller blade is sand casted and cavities that may form during casting are fixed by weld repairing. The aim of the project work was to look into what effects the welding has on the material considering the tensile strength, microstructure and hardness (some parts of a WPS, Welding Procedure Specification)

    Different stress-relieving annealing temperatures have been tested after welding to study possible influences.

    According to the results and analysis the conclusions are that weld repairs and stress-relieving annealing does not affect the properties negative considering the tensile strength, microstructure and hardness.

  • 266.
    Bangshöj, Catharina
    Karlstad University, Faculty of Health, Science and Technology (starting 2013). Karlstad Universitet.
    Integrering av Socialt Ansvarstagande och kvalitetsarbete: En fallstudie inom kollektivtrafiken2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sustainable development is a relevant concern for corporations and organisations, both within the private and the public sector, as the pressure from society at large to act on these issues increases continuously. In order to do so, methods of integration and implementation needs to be developed. One of these methods stems from the idea that quality management and sustainability management share a similar foundation of principles and design of frameworks. The aim of this study is therefore to examine the theoretically supported conclusion, that quality management facilitates working with issues that regard social responsibility (SR), from a practical perspective.

    A case study has been conducted within the public transportation sector on the regional traffic organizer Värmlandstrafik AB (VTAB). The cooperation with the bus operator Nobina regarding quality management issues has been studied. The quality management system that is applied between VTAB and Nobina was developed and designed by VTAB through the industrial PhD project R3 and has led to a changed cooperation conditions between these parties. The effects of these changes have been possible to examine based on the design of the quality management system and the actions taken between the parties due to working with quality management. The information shared within the frames of working with quality management has enabled the development of a model for indicators regarding SR. The case study has been performed through the collection of empirical material by means of interviews, observations and analysis of documents. These means have been applied at both VTAB and Nobina. The empirical analysis has been based on the framework for SR, ISO 26000, and theories that have established the connection between quality management and sustainability management, mainly Total Responsibility Management (TRM).

    The result demonstrates that the quality management system developed by VTAB, and applied in the cooperation with operators, can be used to promote issues regarding SR. However, specific attention needs to be established to the issues inherent in SR frameworks in order to integrate these issues adequately. The parties that cooperate regarding quality management should jointly evaluate what issues are relevant to handle within the cooperation and increase the knowledge regarding these issues in order to secure their compliance. In cooperating around quality management issues, information is shared between the parties that can be used to build indicators that can be used for evaluation purposes from a SR perspective. In this study a model for evaluation that regards the environmental issue of choice of fuel has been developed.

    For future studies the issue of indicators for SR could be researched in order to cover more perspectives for sustainable development. The public transport sector and the organisations that traffic organizers and bus operators constitute are also interesting for future studies from the perspective of how other parts of the organisations contributes to the work with SR issues. Possible perspectives to investigate could be how industry-wide initiatives affects the organisations and how contracts can be formulated in order to promote sustainable development further.

  • 267.
    Baradi, Divyank
    Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Control strategies and inspection methods for welded part2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Present and future demonstrator designs were used to demonstrate the quality assurance of welds. The NDT methods tested on prototype demonstrator parts are: visual inspection, radius gauges, throat size gauge, liquid-penetrant testing, magnetic particle testing and ultrasonics with pulse echo and phased array. The other methods like eddy current, time of flight diffraction, radiography, impression test, macro test and infrared thermographs are currently being analyzed along with their inspection costs.

     

    The control plans for present and future designs with corresponding present and future NDT methods are suggested to minimize a shift in process.

    • Magnetic particle testing revealed a lack of fusion and cracks for fillet welds, whereas ultrasonic pulse echo and phased array identified an internal lack of fusion, inner pores/slag inclusions on butt welds.
    • Ultrasonic PAUT & TOFD could be used for accurate defect identification and thermography for online identification of lack of penetration, depth of penetration and weld parameters.
  • 268.
    Barbier, Christophe
    et al.
    Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Beghello, L
    Magnetic printing for packaging industry: methods and feasibility2006Conference paper (Refereed)
  • 269.
    Barbier, Christophe
    et al.
    Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences, Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Larsson, Per-Lennart
    Östlund, Sören
    Hallbäck, Nils
    Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Karathanasis, Michael
    On material characterization of paper coating materials by microindentation testing2005In: JCT: Journal of Coatings Technology, ISSN 0361-8773, Vol. 2, no 6, p. 463-471Article in journal (Refereed)
    Abstract [en]

    Microindentation as a method for determining important material properties of paper coating materials is studied experimentally and numerically. The bulk of the investigation is concentrated upon the short-lived elastic part of a spherical indentation test, but determination of the failure stress of the coating is also discussed. The results indicate that microindentation can be a powerful tool for material characterization of these materials, but only if careful efforts are made to account for the influence from plasticity as well as from boundary effects

  • 270.
    Barbier, Christophe
    et al.
    Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences, Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Larsson, PL
    KTH Stockholm.
    Östlund, S
    Experimental investigation of damage at folding of coated papers2002In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 17, no 1, p. 34-Article in journal (Refereed)
    Abstract [en]

    To achieve a better understanding of the folding properties of coated papers pertinent to the mechanical behaviour, a microscopic investigation was performed. The influence on the damage levels in the coating from such features as delamination, humidity and paper thickness have been studied

  • 271.
    Barbier, Christophe
    et al.
    Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Larsson, PL
    Östlund, S
    Numerical investigation of folding of coated papers2005In: Composite StructuresArticle in journal (Refereed)
    Abstract [en]

    Folding of coated paper is examined numerically using the finite element method. Particular emphasis is put on the behaviour of field variables relevant for cracking of the coating layers. In the numerical analysis, the basepaper is modelled as an anisotropic elasticplastic material (both elastic and plastic anisotropy is accounted for) while the constitutive behaviour of the coating layers are approximated by classical (Mises) elastoplasticity. The numerical results suggest, among other things, that particular forms of plastic anisotropy can substantially reduce the maximum strain levels in the coating. It is also shown that delamination buckling, in the present circumstances, will have a very small influence on the strain levels in the coating layer subjected to high tensile loading

  • 272.
    Barbier, Christophe
    et al.
    Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Larsson, PL
    Östlund, S
    On dynamic effects at folding of coated papers2005In: Composite StructuresArticle in journal (Refereed)
  • 273.
    Barbier, Christophe
    et al.
    Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences, Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Larsson, PL
    KTH Stockholm.
    Östlund, S
    On the effect of high anisotropy at folding of coated papers2007In: Composite structures, ISSN 0263-8223, E-ISSN 1879-1085, Vol. 72, no 3, p. 330-338Article in journal (Refereed)
    Abstract [en]

    A finite element procedure, developed in order to account for the effect of high anisotropy at folding of coated papers, is presented. The anisotropic behaviour (with very low stiffness in the thickness direction) is modelled using stiff structural elements (trusses and beams). The numerical results indicate that high elastic anisotropy leads to lower strain levels at folding than reported in previous analyses where this effect was not accounted for. High plastic anisotropy, on the other hand, will contradict this result

  • 274.
    Barbier, Christophe
    et al.
    Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Larsson, PL
    Östlund, S
    Eklund, J
    Folding of printed papers: experiments and numerical analysis2003Conference paper (Other (popular science, discussion, etc.))
    Abstract [en]

    Folding of digital prints has been investigated experimentally in order to determine the influence from different features on the residual strength of the folded paper. In particular, the effect of toner-layer, paper-fibre orientation and pre-creasing is investigated and the experimental results are supplemented with numerical ones based on the finite element method. The results indicate that creasing, and to a less extend also fibre orientation, is the most important factor influencing the residual tensile strength after folding

  • 275.
    Barbier, Christophe
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering.
    Rättö, Peter
    Hornatowska, Joanna
    Coating models for an analysis of cracking behavior between folded paper and creased board2012Conference paper (Refereed)
    Abstract [en]

    Creasing coated carton board or folding coated magazine paper, result in large strains in the surface layer of the paper product and might result in surface cracks, which decrease the quality of the products. A better understanding of the mechanical properties of coated layers increases the knowledge needed to reduce crack formation in coated fiberbased materials.The crack area on a coated board was measured after creasing and folding and the crack area on a coated copy paper was measured after folding. A clay pigment and a Ground Calcium Carbonate (GCC) pigment were used. The binder was either an S/B latex or an S/B latex combined with starch.

  • 276. Barker Jørgensen, Bo
    et al.
    Nørh Glud, Ronnie
    Holby, Ola
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Oxygen distribution and bioirrigation in Artic fjord sediments (Svalbard, Barents Sea)2005In: Mar. Ecol. Prog. Ser. 292:85-95Article in journal (Refereed)
  • 277.
    Barklund, Christine
    et al.
    Karlstad University, Division for Business and Economics.
    Gruvesäter, Ulrica
    Karlstad University, Division for Business and Economics.
    Arbetsmiljö och arbetsvillkor: - en studie om stress2006Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [sv]

    Sammanfattning

    Vi avser med denna kvantitativa studie att finna faktorer som kan antas leda till stress. Vi avser också att undersöka respondenternas arbetsmiljö och arbetsvillkor och utifrån deras enkätsvar eventuellt kunna se om de har lågstress- eller högstressarbeten. Uppsatsen baseras på en enkätundersökning genomförd under 2002 av Birgitta Eriksson och Jan Ch. Karlsson vid Karlstads universitet i samarbete med Statistiska Centralbyrån. Enkäten Arbetsmiljö och arbetsvillkor besvarades av 1570 förvärvsarbetande individer. Vår undersökning använder sig av utvalda frågor i enkäten som kan antas kopplas till stress i arbetslivet. I studien undersöks: förekomsten av stressfaktorer, krav, egenkontroll och socialt stöd, tid, sjuknärvaro och ersättbarhet, ledarskap, meningsfullhet samt möjligheten att förena arbete med övrigt liv. I analysen studeras dessa variablers eventuella samband med kön, ålder och yrkestillhörighet.

    Nedan redovisas en kort sammanfattning av frågeställningarnas resultat utifrån tabellerna:

    1. I vilken utsträckning förekommer stress bland respondenterna?

    Överlag visar resultaten att de flesta av respondenterna har få stressfaktorer i arbetsmiljön. Trötthet är dock något som majoriteten av respondenterna upplever efter arbetet, men vi anser att det inte är tillräckligt ofta för att det ska vara oroväckande siffror.

    2. Kan det antas om respondenterna har lågstress- eller högstressarbeten?

    Vi finner att relativt många respondenter i studien har ett lågstressarbete i många avseenden och i relation till de undersökta variablerna.

    3. Hur ser kontakten ut mellan respondenterna och deras ledare?

    Det övergripande resultatet visar på tvetydiga siffror. Trots resultatet anser vi att respondenterna överlag har en relativt god kontakt med deras arbetsledare/arbetsgivare.

    4. Upplever respondenterna en hög eller låg meningsfullhet i deras arbeten?

    Majoriteten av respondenterna upplever att de har en hög meningsfullhet i deras arbeten.

    5. Hur väl lyckas respondenterna förena arbete med övrigt liv?

    En mycket stor andel av respondenterna anser att de lyckas förena arbete med övrigt liv.

    Intressant är att det inte ofta skiljer sig nämnvärt inom kategorierna kön och ålder och inte heller mellan dessa kategorier, oavsett den analyserande variabeln. Däremot visar resultaten på att det ofta skiljer sig mellan arbetare och tjänstemän inom kategorin yrkestillhörighet. Tidigare undersökningar visar på en ökad ohälsa i samhället i form av bland annat stress. Trots detta visar resultaten i vår undersökning att majoriteten av respondenterna upplever en låg grad av stress på deras arbeten.

    Nyckelord: Stress, arbetsmiljö, arbetsvillkor, krav, egenkontroll, socialt stöd, meningsfullhet.

  • 278. Barros, Gustavo Gil
    Influence of Substrate Topography on Ink Distribution in Flexography2006Doctoral thesis, monograph (Other academic)
  • 279.
    Barros, Gustavo Gil
    Karlstad University, Faculty of Technology and Science.
    Influence of Substrate Topography on Ink Distribution in Flexography2006Doctoral thesis, comprehensive summary (Other scientific)
    Abstract [en]

    The printability of paper in flexography is largely dependent on the topographical characteristics of the substrate. Topography imaging instruments make it possible to obtain three-dimensional scans of paper surfaces that can be further used to calculate valuable quality parameters. The primary aim of the work described in this thesis has been to identify and isolate structural properties of the paper surface which significantly influence the ink distribution during printing and limit the subsequently attainable print quality.

    OptiTopo is an optical imaging technique which provides precise and fast topographic scans of both printed and unprinted paper surfaces. The potential and limitations of the technique have been evaluated. The optical requirements on the substrate for an accurate and precise topographic scan were determined. Detail-rendering was substantially improved using a custom-designed restoring filter, and a new enhanced spatial resolution range was established. A combination of further algorithm improvements made it possible also to obtain reflectance-factor-calibrated intensity images of scanned printed surfaces.

    Serious deficiencies affecting the quality of flexographic prints may appear in the form of local unprinted areas (UCA) in a full-tone print, generally caused by incomplete ink transfer. An algorithm detecting and quantifying local uncovered area was developed, tested and successfully integrated with the OptiTopo instrument. A UCA occurrence frequency distribution, indicating the percentage of the uncovered area at a certain topographical elevation, was calculated for different prints. The topographic characteristics of the uncovered areas clearly indicate that surface depressions are the primary cause of uncovered areas in flexographic printing.

    Four different predictive models based on topography thresholding were proposed and tested using two independent quality judgement criteria. These quality indices took into account both the amount and location of the predictions. A deeper understanding of the topographical features governing UCA occurrence was established with a proposed ink bridging effect. The total risk of non-ink-covered areas in flexography printing due to topographical features was estimated.

    The overall influence of paper topography on the flexography printability of full-tone areas was studied and its importance for the ink distribution assessed. The impacts of printing plate hardness, printing pressure, anilox cylinder volume and substrate roughness were quantified. Two typical flexography patterns were identified and their origin discussed: sub-millimetre elongated structures and millimetre-scale blotches.

  • 280. Barros, Gustavo Gil
    Optical Topographical Characterisation for Flexographic Printability2004Licentiate thesis, monograph (Other academic)
    Abstract [en]

    The flexographic printability is largely dependent on the topographical characteristics of the substrate. OptiTopo is a recently developed optical imaging technique, which provides precise and fast topographic scans of both printed and unprinted paper surfaces. The potential and limitations of the technique have been evaluated by comparing OptiTopo scans from a wide variety of commercial paper grades with those of other imaging techniques. The optical requirements on the substrate for an accurate and precise topographic scan were determined. Detail rendering was substantially improved using a custom-designed restoring filter, and a new enhanced spatial resolution range was established.



    Serious deficiencies affecting the quality of flexographic prints may appear in the form of local unprinted areas in a full-tone print, generally caused by incomplete ink transfer. An OptiTopo instrument with an integrated algorithm for the detection of uncovered areas was developed and tested on a range of commercial board samples printed on a laboratory flexographic press. A frequency distribution of uncovered areas, indicating how large a percentage of the surface area with a certain topographical elevation was uncovered, was calculated for the different prints. The topographic characteristics of the uncovered areas clearly indicate that surface depressions are the primary cause of uncovered areas in flexographic printing. Different uncovered area predictability models based on spectral analysis and topographic thresholding are proposed

  • 281.
    Barros, Gustavo Gil
    et al.
    Karlstad University, Faculty of Technology and Science.
    Johansson, Per-Åke
    Mottle and Ink Distribution in Full-Tone Flexography Prints on Coated Linerboard2007In: Journal of Pulp and Paper Science (JPPS), ISSN 0826-6220, Vol. 33, no 4, p. 217-226Article in journal (Refereed)
  • 282.
    Barros, Gustavo Gil
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering.
    Johansson, Per-Åke
    STFI-Packforsk AB, Stockholm, Sweden .
    Prediction of UnCovered Area occurrence in flexography based on topography: A feasibility study2006In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 21, no 2, p. 172-179Article in journal (Refereed)
    Abstract [en]

    This investigation concerns the development and prediction of uncovered areas (UCA) in flexographic full-tone prints based purely on substrate topographic information. Four different predictive models based on topography thresholding were proposed and tested using two independent quality judgement criteria. 

  • 283. Barros, Gustavo Gil
    et al.
    Johansson, P.Å.
    Distribution Of Uncovered Areas (UCA) In Full Tone Flexographic2005In: TAGA J., 2(1), 43-57 (2005)Article in journal (Refereed)
  • 284. Barros, Gustavo Gil
    et al.
    Johansson, P.-Å.
    Prediction of UnCovered Area Occurrence in Flexography Based on Topography ' A Feasibility Study2005In: Accepted for publication in Nordic Pulp Paper Res. Journal, 2005Article in journal (Refereed)
  • 285. Barros, Gustavo Gil
    et al.
    Johansson,, P.Å.
    The OptiTopo Technique for Fast Assessment of Paper Topography ' Limitations, Applications and Imporvements2005In: J. Imaging Sci. Technol., 49(2), 170-178 (2005)Article in journal (Refereed)
  • 286.
    Barréra, Mimmi
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT.
    Engström, Anna
    Karlstad University, Faculty of Economic Sciences, Communication and IT.
    Alkohol i arbetslivet: Faktorer som påverkar de anställdas inställning2008Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [sv]

    Uppsatsen behandlar ämnet alkohol i arbetslivet och syftet är att undersöka inställningen till alkohol i arbetsorganisationer. I studien redovisas faktorer som påverkar detta.

    Frågeställningarna är;

    • Har arbetsorganisationerna en alkoholpolicy och i så fall förmedlar arbetsgivaren vad som faktiskt är nedskrivet i detta dokument?

    • Har företagskulturen, den kultur som finns på orten, så kallad bruksanda samt den psykosociala arbetsmiljön inverkan på inställningen till alkohol?

    – Finns det andra faktorer som kan tänkas påverka de anställdas inställning till alkohol?

    Uppsatsen börjar med ett bakgrundsavsnitt som behandlar viktiga begrepp, alkoholpolitik och dryckeskultur i Sverige samt vad lagen säger om utformningen av en alkoholpolicy. Teoridelen som följer efter utgörs av tre delar som är till grund för vår analys. Dessa tre delar är; ledarskap, företagskultur och arbetsmiljö. Vi har valt att utgå från dessa områden för att kunna se vilken påverkan de kan ha på inställningen till alkohol i arbetsorganisationer. Först tar vi upp ledarskapet som en viktig del i vår undersökning och redogör för olika ledarskapsmodeller samt chefens ansvar och chefen som förebild. Vad gäller företagskultur har vi bland annat valt att redogöra för olika kulturella perspektiv samt vad som är god företagskultur, för att kunna få en djupare förståelse om begreppet. Vi har även diskuterat begreppet bruksanda för att se hur det eventuellt kan påverka arbetsorganisationerna då de företag som vi har undersökt är belagda på så kallade bruksorter. Begreppet arbetsmiljö har avgränsats till den psykosociala arbetsmiljön samt att undersöka det vedertagna begreppet after work, även i detta fall för att öka vår förståelse för begreppen.

    Studiens resultat visar att formella riktlinjer i form av till exempel policydokument inte har så stor påverkanskraft angående alkoholkonsumtion om företaget har en väl förankrad företagskultur. Andra faktorer som är avgörande för individens dryckesmönster är sådant som ålder, livssituation och subkulturer. Resultaten visar även på att det på orterna finns tendenser till vad som brukar kallas bruksanda, både en positiv och negativ sådan. Denna bruksanda präglar även de företag som vi har undersökt.

  • 287.
    Baucke, Stephan
    et al.
    Ericsson Research, Germany.
    Grinnemo, Karl-Johan
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Ludwig, Reiner
    Ericsson Research, Germany.
    Brunström, Anna
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Wolisz, Adam
    Department of Electrical Engineering, Technical University Berlin, Germany.
    Using Relaxed Timer Backoff to Reduce SCTP Failover TimesManuscript (Other academic)
  • 288.
    Baudtler, Rasmus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Laddning för trådlösa hörlurar: med användaren i fokus2016Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport behandlar ett examensarbete för högskoleingenjörsprogrammet inom innovationsteknik och design vid Karlstad universitet. Arbetet är genomfört av Rasmus Baudtler, handledare för projektet var Lennart Wihk och examinator professor Leo De Vin.

    Projektet är utfört på uppdrag av Zoundindustries, Stockholm. Utvecklare av moderna ljudprodukter. Uppdraget har fokuserats mot att hitta en alternativ lösning för laddning till den trådlösa hörluren Plattan ADV Wireless från varumärket Urbanears. Det huvudsakliga målet var att utveckla en lösning utifrån designmetodik baserad på användarstudier och ingenjörsteknik med syfte i att förenkla laddningsscenariot för användaren och öka tillgängligheten för laddning.

    Projektet har utförts enligt den industriella produktutvecklingsprocessen med fokus inom designprocessen. Arbetet startade i en omfattande förstudie innehållande en produktutvärdering, en teknikstudie samt användarstudier genom designmetodik. Detta ledde till i en projektinriktning mot induktiv laddning.

    Med kunskap inom användarens önskemål och teknikens krav sammanställdes en kravspecifikation med en uppdaterad problemformulering. Genom konceptsframtagningsmetoder togs ett flertal koncept fram utifrån kravspecifikationen. Koncepten behandlades sedan genom olika typer av matriser i ett konceptval som resulterade i ett slutgiltigt konceptval.

    Det slutgiltiga valet var en portabel laddningsplatta med inbyggt batteri. Konceptet ansågs förenkla laddningsscenariot och öka tillgängligheten för användaren. Utvecklingsarbetet fortgick genom fastställande av gränssnitt mellan laddare och hörlur, användarscenarion, modell- och prototypbygge. Det slutgiltiga konceptet presenterades i form av 3D-renderingar och uppvisning av prototyperna vid en utställning vid Karlstads universitet. Genom utvecklingsarbetet uppfylldes de krav som ställts på produkten och en möjlig implementering av tekniken i nuvarande produkt kunde bekräftas. Därför anses projektet stå till svar för den problemformulering som ställts upp i projektet.

    För vidare utveckling av konceptet anses följande områden behöva kompletteras eller undersökas: teknikstudie genom expertis, anpassningsarbete av kretskort, utvärdering av produktens anslutningar samt utvärdering av produktens batteri. 

  • 289.
    Beckius, Tobias
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Fjärranalys av vegetationsförändring efter branden i Västmanland 2014: Vegetationsskador och återväxt efter en av de mest omfattande skogsbränderna i Sverige2018Independent thesis Basic level (university diploma), 180 HE creditsStudent thesis
  • 290.
    Beckman, Andreas
    et al.
    Karlstad University, Division for Business and Economics.
    Blomér, Malin
    Karlstad University, Division for Business and Economics.
    Konsten att effektutvärdera: En beskrivande studie om hur kompetensutveckling effektutvärderas2006Independent thesis Advanced level (degree of Magister), 10 points / 15 hpStudent thesis
    Abstract [sv]

    Kompetensutveckling är en verksamhet som får allt större betydelse för organisationer. En av de viktigaste delarna av ett kompetensförsörjande arbete är att utvärdera effekten av en kompetensutveckling. Hur dessa ef-fekter skall utvärderas är ett eftersatt område såväl teoretiskt som praktiskt och forskning om ämnet är nästintill obefintlig. Denna studie genomfördes i samarbete med Stora Enso Skoghalls Bruk i syfte att finna varför detta arbete är så svårgenomträngligt samt att utveckla övergripande riktlinjer att använda som hjälpverktyg för organisationen i dess arbete med att effektutvärdera kompetensutveckling.

  • 291.
    Beckman, Claes
    et al.
    KTH, Center for Wireless Systems.
    Garcia, Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Alfredsson, Stefan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Brunström, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    On the Impact of Velocity on the Train-to-Earth MIMO Propagation Channel: Statistical Observations and Qualitative Analysis2017In: 2017 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting, IEEE, 2017, p. 1865-1866Conference paper (Refereed)
    Abstract [en]

    We provide measured data collected from 97 trains completing over 7000 journeys in Sweden showing that the throughput over LTE is impacted by train velocity. In order to explain these observations we assume that the underlying causes can be found in the implementation of the MIMO system into LTE Rel. 8 and the diffuse scattering of signals from ground reflections.

  • 292. Beder- Miller, Sandra
    et al.
    Andersson, Niclas
    Wilke, Caroline
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Biazzo, Tom
    van Fleet, Rick
    Germgård, Ulf
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Is Conductivity the Best Measurement of Bleach Plant Carryover?2014Conference paper (Refereed)
  • 293.
    Beghello, Luciano
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre.
    A New Generation of Durable Banknote Paper1999Conference paper (Other (popular science, discussion, etc.))
  • 294.
    Beiron, Jens
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Drifteffektivisering av installationssystem i fastigheter: Förstudie1997Report (Other academic)
    Abstract [sv]

    It is possible to improve the energy efficiency of HVAC (Heating, Ventilation and Air Conditioning) systems with the help of building energy management systems. Through deeper knowledge of the dynamics of the system the staff is able to choose a more effective management strategy. Statistics from the energy management system will inform about the system behaviour. It is possible to collect and present the statistics needed thanks to the fast development of information technology and the introduction of computer based building management system.

    A research project will investigate methods for creation of individual models of HVAC systems based on measurement data. Each system will then be simulated for different operating conditions. As a result of the simulation an optimal management strategy can be chosen. Different performance ratios will be used to evaluate the level of energy efficiency. The performance ratios should be defined so that they can be calculated from measurement data.

    This pilot study presents the background, purpose and method of the project. Some examples will be given to illustrate ineffective use due to a badly chosen management strategy.



    Sammanfattning



    Installationssystem kan drifteffektiviseras genom utnyttjande av driftstatistik. Genom att lära känna sin anläggning kan driftteknikern lättare fatta beslut om optimalaste driftstrategi. Med en förbättrad driftstatistik får teknikern många viktiga upplysningar om anläggningens dynamik och beteende. Som konsekvens av den snabba utvecklingen inom informationsteknologin samt införandet av datorstödda styr- och övervakningssystem finns möjligheter till omfattande datainsamling.

    Ett forskningsprojektet skall undersöka metoder att utifrån insamlad driftstatistik skapa individuella modeller av installationssystem. Modellen skall för varje enskild anläggning senare kunna utnyttjas för att simulera olika driftfall och därmed kunna optimera valet av driftstrategi. Olika nyckeltal kommer att användas för att utvärdera och följa upp effektiviseringsarbetet. Nyckeltalen skall definieras så att de kan beräknas utifrån insamlad driftstatistik.

    Denna förstudie beskriver bakgrund, syfte och metodval för projektet. Ett par exempel från utförda mätningar visar på typiska fall av energiineffektivitet som konsekvens av felaktigt vald driftstrategi.

  • 295.
    Beiron, Jens
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Drifterfarenheter från en energieffektiv skola: Vargbroskolan i Storfors2010Report (Other academic)
    Abstract [en]

    Vargbroskolan i Storfors kommun har byggts med ambitionen att minimera energianvändningen utan att ge avkall på inneklimatet. Byggnaden är mycket välisolerad och har ett hybridventilationssystem. Denna rapport redovisar erfarenheter från de inledande två driftåren med fokus på energianvändning och inneklimat.

    Rapporten ingår som del i redovisningen av Demonstrationsprojekt 2006:05,Vargbroskolan, vilket är finansierat inom ramen för Energimyndighetensprogram för Passivhus och Lågenergihus.

    Vargbroskolan är en grundskola för årskurs 4-9 med ca 270 elever. Totala golvytan är ca 4030 m2. Byggnaden togs i drift januari 2008.

  • 296.
    Beiron, Jens
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Frodeson, Stefan
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Wikström, Fredrik
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Drifterfarenheter från ett superisolerat flerbostadshus: Kv SEGLET, Karlstad2010Report (Other academic)
    Abstract [en]

    Seglet är ett 12-vånings punkthus med 44 lägenheter beläget i Karlstad. Byggherre är Karlstads Bostads AB. Huset är byggt med mycket höga ambitioner när det gäller kvalitet och resurshushållning och togs i drift i börjanav 2007.

    Denna rapport redovisar klimatskalets egenskaper och funktion samt utformningen av installationssystemen för värme, ventilation och tappvatten.Rapporten beskriver också drifterfarenheterna från de första årens drift samt de förbättringsåtgärder som utförts.

    Seglets lösningar visar att energieffektivisering och inneklimat kan gå hand ihand. Konceptet med en enkel förvärmning av tilluften löser två problem. Dels kan tilluften tillföras lägenheten utan risk för drag och dels saknar det FTX-systemets nackdelar med utökat servicebehov för filterbyten och ökad elanvändning för tilluftsfläkten. Det välisolerade och täta klimatskalet ger en komfortabel inomhusmiljö. Den befarade risken med höga rumstemperaturer sommartid har inte besannats. Tack vare genomtänkta fönsterplaceringar med solskyddsglas där så är befogat samt goda möjligheter till effektiv vädring har lägenheterna samma temperaturnivå sommartid som motsvarande lägenheter i normalisolerade byggnader. Byggnaden är mycket resurseffektiv med låga förbrukningstal på både energi och vatten. Då största delen av värmebehovet täcks med fjärrvärme står sig byggnaden mycket väl i en jämförande miljöbedömning.

    Nyckeltal för klimatskal och energianvändning

    Medelvärde för klimatskalets värmeisolering, Um, W/m2,K ca 0,21

    Luftläckage, läckflöde vid provtryckning till 50 Pa, l/s,m2Aomg 0,13

    Specifik energianvändning, kWh/m2,år 58

     

     

  • 297.
    Bellström, Peter
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Information Systems and Project Management.
    Kilbrink, Nina
    Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Problem-Based Learning in a Programming Context: Planning and Executing A Pilot Survey on Database Access in a Programming Language2009In: Information Systems Development: Towards a Service Provision Society / [ed] Papadopoulos, G.A, Wojtkowski, G., Wojtkowski, W., Wrycza, S. & Zupancic, J. (eds.), Springer, 2009, p. 867-875Conference paper (Refereed)
    Abstract [en]

    In this chapter we describe a pilot survey on applying problem-based learning (PBL) in an undergraduate programming course. During the course the students have applied PBL as a complement to traditional teaching and learning techniques. The PBL problem in this survey combines both knowledge about programming and knowledge about databases. We argue that to handle programming the students have to learn programming according to the deep approach to learning in order to be able to apply their knowledge in new programming situations and contexts. The result from this pilot survey indicates from both a tutor and a student perspective that PBL could be one method to reach a deeper understanding on how to access databases in a programming language.

  • 298.
    Bellström, Peter
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Information Systems and Project Management.
    Kop, Christian
    Institute for Applied Informatics, Alpen-Adria Universität Klagenfurt.
    Vöhringer, Jürgen
    econob GmbH.
    Semi-Automatic Schema Pre-Integration in the Integration of Modeling Language Independent Behavioral Schemata2012In: ThinkMind: eKNOW 2012, The Fourth International Conference on Information, Process, and Knowledge Management / [ed] Mauri, J.L & Lorenz, P., IARIA Conference , 2012, p. 12-17Conference paper (Refereed)
    Abstract [en]

    In this paper, we address schema pre-integration in the integration of modeling language independent behavioral schemata. In doing so, we propose and present a set of tasks that should be carried out not only to improve and clarify the meaning of a schema, but also to facilitate the resulting time consuming and error-prone phases in the integration process. Due to the complexity of schema pre-integration, domain experts and repositories (e.g. ontologies) are still important sources of knowledge and should therefore be involved during the whole integration process. As its main contribution, the paper offers new tasks to perform in the schema pre-integration process as well as an adjusted and enriched work of previously presented tasks for schema pre-integration.

  • 299.
    Bengtsson, Fredrik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Kartläggning av energiförluster: gällande klimatskal och ventilation för Stora Enso Timbers Pelletsfabrik i Grums2013Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
  • 300. Bengtsson, J.
    et al.
    Wikström, Fredrik
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Effects of whole-tree harvesting on the amount of soil carbon: model results1993In: New Zealand Journal of Forest Science 23: 380-389, 1993Article in journal (Refereed)
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