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  • Axelsson, Filip
    et al.
    KTH, School of Engineering Sciences (SCI).
    Jirwe, Marcus
    KTH, School of Engineering Sciences (SCI).
    Maskininlärning för kvantmekaniska problem2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this article we analyze whether machine learning can be used to help solve problemsin physics. This is examined by implementing an artificial neural network which is trainedto find the energy levels for the quantum harmonic oscillator with and without an externalelectric field. Radial basis functions were used to make the neural network. Monte Carlomethods were used for heavy calculations. The method was shown to work well in somecases but had problems for large electric fields. The problems that occured were that theconvergence became unstable, with leaps in the energy and that the system did not alwaysconverge to the right energy level.

  • Engstedt, Erik
    KTH, School of Engineering Sciences (SCI).
    Kvant-periodiska potentialer med föroreningar: Effekten av föroreningar på den endimensionella Kronig-Penney potentialen2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this project a model of a quantum periodic potentials with impurities is implemented and explored. The focus lies on studying the effects that different types of impurities have on the energy-band structure found in a one-dimensional Kronig-Penney potential. The method used is based on a numerical matrix method for solving the Schrödinger equation for periodic potentials. The results can be summarized in that the impurities mainly change the band structure in two ways. The first effect is that new, almost discrete energy levels are introduced into the previously empty energy gaps which correspond to the intrinsic energies of the isolated impurities. The other observed effect is that the previously continuous bands of the periodic potential without impurities split up but still cover roughly the same range of energies as before, at least when the impurity density is sufficiently low. The results reflect some important feature found in real doped materials and looking forward, the work done here can hopefully be applied to analysis of more realistic three-dimensional models.

  • Conneryd, Jonas
    et al.
    KTH, School of Engineering Sciences (SCI).
    Lassen, Anna
    KTH, School of Engineering Sciences (SCI).
    Explicita symplektiska integratorer för icke-separabla Hamiltonianer i molekyldynamik.2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In molecular dynamics, mathematical models of metallic systems should in general have the temperature of the system as a dependent variable \cite{acklandTemperatureDependenceInteratomic2012}. In particular, the potential energy term of the Hamiltonian function of the interaction model should be dependent on temperature in addition to interparticular distances. This puts the Hamiltonian function on a form which is generally non-separable. Conventional explicit numerical methods which are symplectic when used to integrate the equations of motion of systems with separable Hamiltonians are not in general symplectic when used to integrate the equations of motion of systems with a non-separable Hamiltonian. Hence, an integrator which sustains symplecticity when used in a system with non-separable Hamiltonian is sought. A family of explicit integrators which are symplectic when integrating systems with a non-separable Hamiltonian are shown to exhibit similar or superior performance to the Velocity Verlet and fourth-order Runge-Kutta schemes, albeit with the drawback of numerical instability when used on a system where forces depend exponentially on the inverted interparticular distances. To the knowledge of the authors, this study is the first time this family of integrators is applied in the context of molecular dynamics. The results of this study provide a first indication that a comprehensive solution to the problem of integrating the equations of motion of a system with a non-separable Hamiltonian explicitly and symplectically is not provided by the considered family of integrators. However, further investigations into using this family of integrators in other molecular dynamics systems than those investigated here are needed to provide a more definitive conclusion.

  • Fransén, Daniel
    KTH, School of Engineering Sciences (SCI).
    Klassisk–kvantmekanisk tidsalternerande metod för simulering av strålningsinducerade defekter i metaller2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Radiation damage in metallic components is unavoidable near the core of nuclear fission and fusion reactors. The key parameter for all radiation damage calculations is the threshold displacement energy, commonly determined through molecular dynamics (MD) displacement cascade simulations based on the embedded atom method (EAM), and recently also using the quantum mechanical density functional theory (DFT). DFT is more accurate and provides better agreement with experimental data compared to the considerably much faster EAM. In the present study, the dynamics of DFT and EAM based MD displacement cascade simulations is compared. The differences predominantly appear after 150 to 200 fs or more. A method is therefore proposed which substitutes the first part of a DFT simulation for EAM. The simulation time reduction is considerable due to the low cost of EAM, and due to the fact that a majority of the simulation time is usually spent in the first high energetic collisions which occur in this early part of the collision process. The proposed method is tested by determining the threshold displacement energy and comparing the results to calculations based purely on DFT and EAM. For the tested cascade directions, the method provides good agreement to DFT, including cases where EAM deviates from DFT. With approximately 1/5 of the DFT simulation cost, the proposed alternating EAM-DFT method seems promising but requires further study and verification.

  • Bergström, Max
    et al.
    KTH, School of Engineering Sciences (SCI).
    Sandgren, Jona
    KTH, School of Engineering Sciences (SCI).
    Elflygplan, en konceptuell design2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report of a conceptual design of an electric driven aircraft was driven with the goal of making the flying sector more environmentally viable. The designated mission was chosen freely for the airplane. The result became a short distance plane with a range of 500 km, seating for eight passengers, primarily aimed towards companies. It was decided that the plane would have its cruising altitude at 4500 m, with a cruising speed of 280 km/h and have a short takeoff and landing distance. The airplane would be able to climb with a vertical speed of 6.67 m/s and have a stall speed of 150 km/h. From the specifications and the assumptions regarding different variables, the fuel weight and total weight was decided to be 2654 kg and 8294 kg respectively. The range of a corresponding aircraft driven with fossil fuels were calculated to be 2070 km. A constraint diagram was then constructed based on five chosen requirements. From this diagram the least power to weight and the highest possible wingloading was determined. A point slightly higher than the least required power to weight was chosen, leading to the engines needing to produce 1900 hp at takeoff. The wing area could be calculated from the decided wingloading and it ended up at 44 m^2 with a wingspan of 23.8 m because of a previously chosen aspect ratio. The length of the fuselage was calculated to be 16.2 m and its effective diameter 2.03 m. Finally an initial layout could be developed where a relationship between the wing and horizontal stabilizer was calculated and the center of gravity for the airplane was placed. The final airplane has a longer wingspan, is heavier and has a shorter range than what similar aircraft that are not driven with electricity have. It can be seen that the cruise speed can be increased above the 280 km/h in the constraint diagram, but the specified requirements were met, which was the main priority.

  • Byström-Troyan, Filipp
    et al.
    KTH, School of Engineering Sciences (SCI).
    Isaksson, Ola
    KTH, School of Engineering Sciences (SCI).
    eVTOL Koncept för Stadstransport2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The objective of this project in aeronautical engineering is to conceptually design an electric aircraft for service in the year 2030. The mission profile of this aircraft is to fly in urban environments with electric vertical take-off and landing (eVTOL) by utilizing tiltrotors. Flying trips within or between cities, the eVTOL aircraft combines the take-off advantages of helicopters with the cruise speed and efficiency of airplanes, making for a versatile aircraft suitable for the urban environment. With a capacity of one pilot and three passengers with luggage the range is 315 km with a cruise speed of 100 m/s at an altitude of 500 m. With a wingspan of 10 m and a fuselage length of 9.2 m the aircraft has a take-off weight of 2 metric tonnes out of which 350 kg are battery packs. The eVTOL has two contra-rotating propellers on the tips of the forward swept wing and two single propellers on a V-tail to a total of six 194 kW electric motors in four tilting assemblies providing an operational peak thrust-to-weight ratio of 1.39.

  • Clauson, Carl
    et al.
    KTH, School of Engineering Sciences (SCI).
    Sloma, Malte
    KTH, School of Engineering Sciences (SCI).
    Simulering av inverterad pendel med analytisk mekanik2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Analytical mechanics is an alternative to Classical (Newtonian) mechanics for calculating the movement of particles and systems of particles. In this paper we analyze three different mechanical systems using analytical mechanics. We then implement this into the maple based software "Sophia" to further analyze how changing some of the parameters alter the behavior of the system. One of our main focuses in the report is studying the stability of an inverted pendulum. In 1951 the Russian physicist Pyotr Kapitza, figured out that the pendulum could be stabilized in the upside-down position by forcing it into a rapid vertical oscillation. We examine the boundaries of this stability and explore if the pendulum can instead be stabilized using an elliptical oscillation

     

  • Vestberg, Albin
    KTH, School of Engineering Sciences (SCI).
    Modellering av åsiktsdynamik med maskininlärning2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Opinion dynamics is about how opinions of people, also called agents, in a group changes in time. The aim of this report was to find out if it is possible to use machine learning with artificial neural networks to, from a given initial condition, compute the opinion dynamics for the agents in the group. Thousands of random initial conditions were generated and the dynamics were calculated using a model from R. Hegselmann and U. Krause. The solutions were then used as data to train artificial neural networks. When the trained neural networks were used on new initial conditions it was found that these could, with varying results depending on the method and number of agents, recreate the opinion dynamics and give answers that were close to the real solutions. The number of agents used were between two and ten. The best results were obtained when groups with two agents were examined. When the number of agents increased the errors in the solutions with machine learning also increased, but the errors were still small enough so that the solutions can be considered as good recreations of the opinion dynamics.

  • BERG WINCENT, BOEL
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Gångavstånd för resor med elsparkcykel: En studie baserat på elsparkcykelaktören Voi Technology i Stockholm2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Electric scooters, or e-scooters as they also are called, were launched in California in USA as a bike share system, in 2017. A year later, in September 2018, the Swedish company Voi Technology launched the first e-scooters in Stockholm, Sweden. Bike share systems has been around since the 1960s but has grown substantially in the past 15 years. New technical solutions have solved past problems with theft and payment in bike shares. Since e-scooters are new, there is a lack of research and knowledge about practical use. The study aims to examine how long users of e-scooters walk to utilize the service. Travel data from Voi Technology is used to determine walking distance. The distance from the location where the app was opened to the location where the e-scooter trip begun was measured. The result was also compared the walking distance of other bike share systems and travelers of public transportation. The majority of e-scooter users walk less than 100 meters and 38 per cent walk less than 50 meters. The users have the shortest walking distance in the morning and the longest in the afternoon. During the weekend's users walk further than in weekdays. The users who travel longer distances with the e-scooters don’t walk further than other users. About a third of the users walk in the opposite direction of travel, to some extent, to catch an e-scooter. That indicates that the aim of the user in general seems to be to always have the shortest possible walking distance to the e-scooter.

  • Krusell, Ellen
    et al.
    KTH, School of Engineering Sciences (SCI).
    Julin, Lovisa
    KTH, School of Engineering Sciences (SCI).
    Klustring av Sveriges kommuner: En studie av sambandet mellan kommuners egenskaper och valresultatet2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the autumn 2018 political elections were held in Sweden and consequently it is interesting to investigate what can affect how people vote. The purpose with this report is investigating if there are correspondences between the characteristics of a municipality and how the people in that municipality voted in the general election. Clustering on data sets with municipality characteristics and municipality general election statistics from 2018 is the basis of this study. K-means clustering and hierarchical clustering are the clustering methods that are used. In the report results of the clustering and the construction of a method for comparing clusterings are presented. The results show that there are some correspondences but that clustering is not the optimal method for analysing this data set.

     

  • Karlsson, Örn Arnar
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS.
    Design and implementation of a data acquisition system with filter quality evaluation2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Particulate matter is a growing health concern that is considered to contribute to many diseases. To develop appropriate air filtration systems, we need to understand how particulate matter affects air filters. In this project, we implement an automated data acquisition system for an air filter test rig. The data acquisition system allows us to gather empirical data on how particle matter affects air filters over time. Although the quality of the air filters does not reach critical levels, there is a measurable degradation. The collected data is used to train and validate a machine learning model that can evaluate air filter quality. This machine learning proved to be a powerful tool in air filter evaluation and performs with 99% accuracy on test data. The result of this project is a fully functioning data acquisition system along with a user interface that considerably reduces the number of man-hours needed to perform tests of filters. In addition, the automated data acquisition system can notify the operator when the rig needs a change of filter or when certain faults occur. Unfortunately, the project did not reach its original goal of being able to automatically determine when the test rig needs maintenance or re-calibration.

  • Wikberg, Elena
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Catalytic Upgrading of Fast Pyrolysis Bio-oil Using Zeolites2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Fast pyrolysis bio-oil is considered as a possible source for production of liquid bio-fuels and bio-chemicals enabling the necessary transition to a renewable energy system. In this Master’s thesis work the upgrading of fast pyrolysis bio-oils with Fluid Catalytic Cracking (FCC) conversion process at industrially relevant conditions is studied using Fluid Catalytic Cracking Micro Activity Test (FCC MAT) unit at RISE ETC in Piteå, Sweden. The study is focused on evaluating the process in terms of production of value-added products including petrochemical materials, such as propylene and benzene, toluene, xylene (BTX), and petroleum range liquid biofuels. The evaluation of the process was based on the upgraded products yield and quality characterized by the chemical composition of collected liquid and gas samples with regards to several influencing factors including origin of the bio-oil, addition of ZSM-5 zeolite to the commercial catalyst and FCC operation parameters, such as reaction temperature, catalyst to oil (CTO) ratio and ZSM5 zeolite catalysts acidity. Several analytical methods were applied for characterization of both feedstock and products, including GC MS analysis and determination of the boiling range distribution of the liquid products by simulated distillation. The results of this work showed that the process of upgrading pure pyrolysis bio-oil was challenging and required further studies to develop a practical operating process. While the process of co-feeding of the pyrolysis bio-oil with commercial FCC fossil feedstock was determined as feasible at industrially relevant conditions. Catalytic conversion of co-fed pyrolysis bio-oil at the ratio of 20/80 resulted similar petrochemical products to commercial fossil feedstock with full deoxygenation of pyrolysis bio-oil. Moreover, the results showed that high catalytic reaction activity conditions with high reaction temperature along with the use of ZSM-5 zeolite were favored for maximizing the BTX and gasoline range products.

  • Rodríguez, Cristina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Measuring Shoulder Abduction in a Healthy and Young Population: A Feasibility Study2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The ability to maintain an independent living at higher age is closely linked to the physical function of an individual. The evaluation of the upper limbs, including the muscular strength of the shoulder, elbow or wrist has received little attention, yet arms are used in most daily tasks. The upper extremity physical performancecan be measured in several ways but none of them has the recognition to be theprimary method. The aim of this experimental study is to test the new devicedeveloped by Erik Almgren and assess whether this can be a valid tool to reliablyassess abduction shoulder strength.

    Fourteen healthy young subjects participated in this study. After placing in the left wrist the new device, they performed three types of tests: Full Range of Motion, Static measurements and Dynamic measurements. Three trials were done in each test with a recovery of 30 seconds.

    The results of the study showed that the Static measurements were similar to the ones obtained in previous studies in the past for both angles and force. For the first time, the study includes dynamic measurements of the moment of the shoulderjoint. Peak dynamic moments were found to be on average 6.43 N·m ± 1.00 N·mfor the females and 7.90 N·m ±2.33 N·m. This value is 6% lower than the test population’s average maximum static moments- result which in accordance withthe inverse relationship between force and velocity.

    The feasibility of this new device to be used outside a biomechanics lab has been proved, however, further research needs to be done in order to validate angles and measurements of the subjects.

  • Kharazmi, Parastou
    KTH, School of Architecture and the Built Environment (ABE).
    Monitoring the gelation time and curing process of a reinforced polyester lining-original data2019Data set
    Abstract [en]

    Polymer linings used in sewer rehabilitation technologies are expected to cure fast in order for the renewed line to return to the service quickly and with minimum disruption.  This dataset includes the original data obtained from the thermal analyses of a reinforced polyester composite used as pipe lining, including studying gelation, enthalpy and curing process for a better understanding of the material's curing behaviour after application in the field. 

  • Andersson, Malin
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Simuleringsbaserad analys av pendelbåtstrafik i Stockholm2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This paper analyzes how an agent-based simulation model of Stockholm can be used for water transitplanning. A new route for commuters by boat was added to the model of Stockholm’s existingtransport system and evaluated. By comparing results from the model and statistic data fromTrafikförvaltningen Region Stockholm during the morning rush-hour, a scale factor was calculated.The scale factor was later used to adjust the number of travelers on the added new water transit routeas the model underestimate the number of persons who use the available public transport by boat. Thelarge size of the calculated factor made the results uncertain when trying to predict any effects the newroute would have, e.g. on congestion in the system. Simulations of the new transit line resulted in amajority of short trips, between stations were the other public transit options took longer routes. Thetransit stops close to the city centre were used the most and most trips were conducted between them.To gain an improved ability to simulate water transit, continued studies of people’s preferencesregarding mode choice appear to be crucial.

  • LIDSTRÖM OLSSON, DANIEL
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Inlandsbanan – befintliga spår, ny trafik: Förutsättningar för regional spårtrafik i glesbebyggda områden2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When the car dependency grew under many decades in Sweden parts of the rail network was shutdown or got reduced traffic due to the diminishing demand for rail travel. The railway lines affectedwere primarily those in rural areas with an already low number of travellers. One of these linesthreatened to be shut down was the line called Inlandsbanan (Inland line). Inlandsbanan was savedby the municipalities located along the line who now manage the railway by a co-owned company.Since the railway became managed by the co-owned company the railway has mostly been used fortourist-oriented traffic and freight traffic.Today the conditions are different, the demand for rail travel has increased due to a general highertransport demand and an increased environmental awareness. This study has been carried out tofind out if there is possibility to re-establish regional rail traffic for passengers on Inlandsbanan.The study has been carried out using statistics of current travel volumes and inhabitants in thepopulation centres along the line. This data has been analysed with support from earlier studiesregarding regional rail traffic and public transport in rural areas. As an extra tool in the study asimulation program has been used to estimate the travel demand for the line.The study found that the current low speed on Inlandsbanan is the biggest obstacle for implementingan attractive regional rail service on the line. The train is too slow in comparison to the car andtherefore it is not able to gain any considerable share of the total amount of travellers. It is possibleto replace regional bus service at some parts of the line since the train has some minor time gaincompared to the current bus service and the train could also offer a higher level of comfort.

  • Zea, Elias
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Compressed sensing of impulse responses in rooms of unknown properties and contents2019In: Journal of Sound and Vibration, ISSN 0022-460X, E-ISSN 1095-8568, Vol. 459, article id 114871Article in journal (Refereed)
    Abstract [en]

    This paper introduces a method to recover unmeasured room impulse responses (RIRs) in acoustical spaces with unknown properties and contents, by means of a compressed sensing methodology. Methods published in the existing literature have been validated in empty, convex rooms; a limited subset of the many, diverse acoustical spaces one can encounter. It results a challenge to represent such diverse wave phenomena with a sparse set of plane waves or equivalent sources, given the coupling between the sparsity of such representations and hypotheses regarding the properties of the acoustical space and its contents, far-field measurement distances, and other parameters. In contrast to this philosophy, the method introduced in this paper exploits the sparsity inherent to the mathematical structure of the wavefronts present in the RIRs, which without further hypotheses carry themselves all the information about the wave propagation in the room. In essence, the measured RIRs are instead represented with a sparse set of curved elementary functions of various sizes, propagation directions and times of arrival, which are linked with the various shapes and locations of the unknown scatterers and boundaries in the room. The main contribution of this work is thus to enable the measurement of RIRs in more complex acoustical spaces, while keeping the number of microphones to a minimum with the use of compressed sensing. The method is formulated as a sparse optimization problem, and the solution is obtained with an iterative thresholding algorithm whose threshold value is determined from the measurements. An analysis of sensing coherence is included, and the performance of the method is experimentally evaluated with 1D microphone array measurements in two lecture rooms and one meet-ing room. For the sake of comparison, the RIRs are also linearly interpolated using a low-pass filter in the wavenumber-frequency domain. The experimental results demonstrate that the proposed method is superior than linear interpolation in all the cases investigated, motivating further development of the method to higher spatial dimensions. In terms of accuracy, the proposed method attains recovery errors in the same order of magnitude as those attained by methods in the literature, yet here the acoustical spaces have arbitrary contents and exhibit more complex geometries and boundary conditions.

  • Rogers, Patrick
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering. RISE Research Institutes of Sweden AB.
    Silfwerbrand, Johan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges. KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Selander, Anders
    Cementa AB.
    Gram, Annika
    RISE Research Institutes of Sweden AB.
    BULK HYDROPHOBICSTRUCTURAL CONCRETE FOR USE IN NORDIC CONDITIONS - INITIAL STUDY2017In: 8th International Conference on Water Repellent Treatment and Protective Surface Technology for Building Materials (Hydrophobe VIII), Hong Kong, December 7-9, 2017., Hong Kong, 2017Conference paper (Other academic)
    Abstract [en]

    Reinforced concrete is a universal composite product available globally. The ability to shape and cast concrete to fit the needs of the end user at a relatively low cost is its main advantage. The service life of a reinforced concrete structure can be over 100 years. Concrete and the embedded steel though can degrade over time due to frost damage, chloride induced corrosion, alkali silica reaction etc. Costly repairs and social inconvenience are often the consequence. External mass flow of water through defects in the concrete or in the concrete’s pore structure is a leading cause of material breakdown of the cement paste or reinforcement bars. The reduction of this flow would be beneficial as this has the potential to hinder the transport of undesired ions such as chlorides or sulphates into the cement paste. In Justnes [1] various chemicals were summarized and demonstrated as having hydrophobic or damp proofing properties in concrete, in particular vegetable oils at an application 1.5% of cement weight with a water to cement ratio of 0.5. This paper will also extend beyond that limit for bulk hydrophobic agents in concrete in reducing water permeability and diffusion of external chlorides within this composite material. The resulting fresh and hardened properties will also be evaluated. Finally, the most effective concretes will then be exposed to real life external environments, such as a Nordic tunnel, over several years. The study is in its infancy and so preliminary results will be presented.

  • ANDRÉN JAKOBSSON, NICOLINA
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    BOHMAN, SIMON
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    A Generative Design of TimberStructures According to Eurocode: Development of a Parametric Model in Grasshopper2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The interest of timber structures has in recent years increased, primarily due tothe environmental benets of timber. This has created an increased demand forstructural engineers with timber expertise. At the same time the concept of structuralparametric design have become more popular. This new way of working withdesigns enables for architects and engineers to explore dierent geometries in earlystages of a project. However, the combination of a parametric workow and timberdesign have so far been limited due to the complexity of the material.This thesis aims to create an parametric workow within the visual programmingenvironment Grasshopper. This enables analysis of structural design simultaneouslywith a cross sectional and topological optimization of timber structures. The structuralanalysis is performed with Karamba which is a plug-in tool to the Grasshopperenvironment. The design verication based on Eurocode EN-1995 have been manuallyscripted in python components. The parametric model have been applied to acase where the main bearing bearing of a glass roof is to be designed. Three dierentgeometries have been evaluated with regard to cross sectional dimensions andgeometrical shape.The framework with a truss turned out to be a preferable design if only consideringweight, deection and utilization. The truss frame provides the lowest weight and thesecond smallest displacement. Furthermore, a comparison of the structural analysisand design have been performed with the FEM-program Robot. The compassionshow similar results, increasing the reliability of the Grasshopper model and theresults from this tool. It conrms it is possible to perform generative design oftimber structures within the same interface.The Grasshopper model is limited and can not handle all variations of 2D timberstructures. The complexity and variation of such calculations in conjunction with theEurocode have not been implemented during the time-span of this thesis. However,it is general within the limitations of the case study meaning a variety of framegeometries can be evaluated.

  • Sörlin, Sverker
    Philosophy and History, KTH, School of Architecture and the Built Environment (ABE), Philosophy and History of Technology, History of Science, Technology and Environment.
    An environmental reckoning in the High Arctic: Sverker Sörlin lauds an integrative history of remote Beringia, revealing the cost of overexploitation in fragile ecologies.Review of Batsheba Demuth: Floating Coast: An Environmental History of the Bering Strait (New York: W.W. Norton, 2019).2019In: Nature, E-ISSN 1476-4687, Vol. 572, no 8 August, p. 177-178Article, book review (Refereed)
  • Malkki, Pertti
    KTH, School of Industrial Engineering and Management (ITM), Learning.
    Kreativitet och fysik: En kvalitativ studie om gymnasieelevers uppfattningar om kreativitet i fysikoch förslag på förbättringar2019Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • Ori, Miklós
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Local Buckling of Doubly-Symmetric I-Sections Subjected to Warping Torsion: The limitations of the Reduced Cross-Section Method under unconventional loading2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In regular design practice, when it comes to conventional loading, such as uniaxial compression and bending, the local buckling of thin plates is taken care of through cross section classification. The effect of warping torsion, which also gives rise to normal stresses in the section, however, is typically not considered in the process.

    Present work aimed to uncover the influence of warping torsion on the phenomena of local plate buckling and to investigate the limitations of the effective width method when it was applied against its intended use. In the case of varying results, a simple correction to the calculation method was to be developed to improve accuracy.

    The examined I-sections were tested to failure and results were obtained with two different approaches: with finite element method and a Eurocode-based hand-calculation. The finite element models were refined to closely mimic physical experiments and their results were accepted as the true resistance of the sections, while the calculation method tried to capture the structural response in a practical, easily understandable way.

    The calculated results showed reasonably good accuracy with that of the finite element analysis. However, what really stood out was how similar the change in resistance was when the section parameters were manipulated. Through a properly chosen function, this allowed for the creation of an exponent that could modify the calculated results to achieve an even greater accuracy.

    The eccentricity of the applied load on the system was also manipulated to alter the proportion of normal stresses due to the two examined effects. It became clear that the stresses from warping in the applied calculation model were underestimated and the otherwise conservative method of effective width lost much of its safety margin when its application was extended to warping as well. Consequently, the consideration of stresses from warping in the regular design process and stability control of commonly used thin walled open sections seemed to be justified. The effective width method could not reliably cover the issue with retaining its original margin of safety.

  • Hacks, Simon
    et al.
    Steffens, Andreas
    Hansen, Peter
    Rajashekar, Nikhitha
    A Continuous Delivery Pipeline for EA Model Evolution2019Conference paper (Refereed)
  • Borozanov, Vasil
    et al.
    Hacks, Simon
    Silva, Nuno
    Using Machine Learning Techniques for Evaluating the Similarity of Enterprise Architecture Models2019Conference paper (Refereed)
  • Hacks, Simon
    et al.
    Lichter, Horst
    A Probabilistic Enterprise Architecture Model Evolution2018Conference paper (Refereed)
  • Barbosa, Amanda
    et al.
    Santana, Alixandre
    Hacks, Simon
    KTH, School of Electrical Engineering and Computer Science (EECS).
    Stein, Niels von
    A Taxonomy for Enterprise Architecture Analysis Research2019Conference paper (Refereed)
  • Timm, Felix
    et al.
    Hacks, Simon
    KTH, School of Electrical Engineering and Computer Science (EECS).
    Thiede, Felix
    Hintzpeter, Daniel
    Towards a Quality Framework for Enterprise Architecture Models2017Conference paper (Refereed)
  • Mathew, Delin
    et al.
    Hacks, Simon
    Lichter, Horst
    Developing a Semantic Mapping between TOGAF and BSI-IT-Grundschutz2018Conference paper (Refereed)
  • Hacks, Simon
    et al.
    Timm, Felix
    Towards a Quality Framework for Enterprise Architecture Models (Extended Abstract)2018In: EMISA Forum, ISSN 1610-3351, Vol. 38, no 1, p. 32-33Article in journal (Refereed)
  • Hacks, Simon
    et al.
    Lichter, Horst
    Towards an Enterprise Architecture Model Evolution2018Conference paper (Refereed)
  • Hacks, Simon
    et al.
    Brosius, Maximilian
    Aier, Stephan
    A Case Study of Stakeholder Concerns on EAM2017Conference paper (Refereed)
  • Schalk, Meike
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Architecture, Urban Design.
    Kristiansson, ThérèseArkDes.Mazé, RamiaAalto University, Helsinki.
    Feminist Futures of Spatial Practice: Materialisms, Activisms, Dialogues, Pedagogies, Projections2017Collection (editor) (Refereed)
    Abstract [en]

    Architecture and the arts have long been on the forefront of socio-spatial struggles, in which equality, access, representation and expression are at stake in our cities, communities and everyday lives. Feminist spatial practices contribute substantially to new forms of activism, expanding dialogues, engaging materialisms, transforming pedagogies, and projecting alternatives. Feminist Futures of Spatial Practice traces practical tools and theoretical dimensions, as well as temporalities, emergence, histories, events, durations – and futures – of feminist practices. Authors include international practitioners, researchers, and educators, from architecture, the arts, art history, curating, cultural heritage studies, environmental sciences, futures studies, film, visual communication, design and design theory, queer, intersectional and gender studies, political sciences, sociology, and urban planning. Established as well as emerging voices write critically from within their institutions, professions, and their activist, political and personal practices. Feminist Futures of Spatial Practice deepens and broadens how we can understand and engage with different genders, bodies and peoples, diverse voices and forms of expression, alternative norms and ways of living together.

  • Public defence: 2019-09-06 10:00 Kollegiesalen, Stockholm
    Aljure, Mauricio
    KTH, School of Electrical Engineering and Computer Science (EECS).
    Pre-breakdown Phenomena in Mineral Oil Based Nanofluids2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Mineral oil is a dielectric liquid commonly used in high voltage equipment such as power transformers. Interestingly, it has been experimentally observed that the dielectric strength of the mineral oil is improved when nanoparticles are added. However, the mechanisms behind these improvements are not well understood, hindering the further innovation process of these so-called nanofluids. This thesis aims to contribute to the understanding of the mechanisms explaining the dielectric strength improvement of the base oil when nanoparticles are added.For this, several experiments and numerical simulations are performed in this thesis. The initiation voltage of electric discharges infive different kind of nanofluids was measured. The large data set obtained allowed to cast experimental evidence on the existing hypotheses that are used to explain the effect of nanoparticles. It is found that hydrophilic nanoparticles hinder the electric discharge initiation from anode electrodes. On the other hand, electric discharge initiation from cathode electrodes was hindered by nanoparticles with low charge relaxation time.The electric currents in mineral oil and nanofluids were also measured under intense electric fields (up to 2GV/m). It is found that the addition of certain nanoparticles increases the measured currents. The possible physical mechanisms explaining the measured currents inmineral oil with and without nanoparticles were thoroughly discussed based on results of numerical simulations. Preliminary parameters used in this thesis to model these mechanisms led to a good agreement between the measured and simulated electric currents.

  • Ödborn, Sofia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    The Science of Deodorants2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Deodorants are cosmetic products that are consumed by people regularly and globally. In this thesis, the opportunities to develop a deodorant for the Swedish cosmetics brand IDUN Minerals AB is investigated. The deodorant market in Swedish pharmacies, deodorant formulation and deodorant packaging are studied. Furthermore, controversial ingredients, such as synthetic aluminum compounds, are explored.

    The scientific aspects of using synthetic aluminum compounds, which are used as antiperspirant in deodorants, are investigated. There is a general fear that they may increasethe risk of developing breast cancer. However, after a full review of exciting scientific evidence, it is clear that there is currently no study that can prove or disprove the suspicions. The use of aluminum-based antiperspirants therefore continues to be a controversial topic.

    The conclusion of this thesis is that there is a market opening for IDUN Minerals, especially since they aim for a synthetic aluminum-free, unperfumed and preservative-free deodorant. Furthermore, it is concluded that a Nordic Swan Ecolabel would make their product uniquein its product category. Lastly, it is determined that traditional plastic packaging is more accessible and possesses many favorable properties, but that bioplastics should be further researched.

  • Mado, George
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Överföring av NIR metod för kvantitativ analys mellan olika instrument2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This diploma work treats the transferring of a method from an Antaris NIR-instrument at AstraZeneca Macclesfield to a Bomem 3600 NIR-instrument at AstraZeneca Gärtuna. The method is used to ensure that by-product form L is below the specified limit value for the product.

    Quantitative NIR methods are not absolute. They are predictive methods that are based on the inclusion of spectra for several samples that are also analyzed with a reference method. Then, a multivariate computer program is used that relates each spectra to its value with linear regression.

    To transfer a method between two different NIR-instruments, you need to mathematically transfer the spectra on which the multivariate model is based on, so that they are mathematically analyzed on the instrument that the method is transferred to. The raw data used to build the model is data from the NIR-instrument in Macclesfield and the NIR instrumentin Gärtuna. The transformation of data is performed in Matlab with local centering. The transformed data is then used to build the model in SIMCA 14 which is a software for managing multivariate data models. When the model's correctness is verified, a method is created in SenISS that uses the newly built model to predict Form L in the product.

    The model is a 2-component PLS model that has the SNV and second derivative spectral filters. These filters contribute to signal correction and reduce the individual differences in spectrum.

    To verify the correctness of the model, several parameters have been examined, these parameters are: linearity, accuracy, repeatability and selectivity.

    The linearity is verified by means of a validation set where the model can predict the content of Form L which is then compared with the Form L value determined with reference method. Regression statistics are calculated to verify that the slope includes the value 1 and that the intercept includes the value 0 in a 95% confidence interval.

    The accuracy is verified by examining how much the predictions deviates from the reference method. The accepted value is 20% RSD. The model has a maximum RSD value of 11.7%.

    The repeatability is verified by analyzing 2 capsules from 2 different batches 10 times each. Then the pooled standard deviation and a 95% confidence interval is calculated.

    The selectivity of the model is verified by analyzing capsules with other contents, 5 capsules with different contents is analyzed. The model gives high values of DModX (the distance for each observation to the model) and/or Hotelling's T2 (the distance from the observation to the center of the model) which means that the analyzed capsules with different content deviate from the model.

  • Kourieh, Ilona
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Kan hållbarheten på referenslösningar förlängas?2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Drug companies must ensure that the products that are manufactured meet the requirements and are of approved quality. The company Recipharm Karlskoga AB must control their products and this is done by example using reference solutions. These reference solutions have certain life time and the company wants to find a way to extend the life time of three reference solutions belonging to the company's analytical methods for high-performance liquid chromatography (HPLC.). This will lead to reduced working hours for the company employees, a cost reduction and a reduction of emissions/use of active pharmaceutical ingredient. This can therefore benefit the environment. The aim of this workis to find a way to extend the life time of the three reference solutions.

    R2 value and relative standard deviation for the double injection and replicas one and two were calculated in order to be able to estimate the life time of the products from the various sample storages placed in room temperature, refrigerator and freezer.

    The products that are analysed contain active pharmaceutical ingredient. Product one contains Lidocaine, Hydrocortisone acetate and Hydrocortisone and is currently sustainable according to the control method. The sample storage for product one was in the freezer and it had a prolonged life time of six days.

    Product two contains Metagin, Propagine and Lidocaine HCl. Today’s life time is five days according to the control method. It was analysed in three different sample storage rooms, room temperature, refrigerator and freezer. The product stored in the freezer lasted for 12 days while the product stored in both room temperature and in the refrigerator was able to sustain for 15 days. The choice of selected sample storage room for product 2 depends on the company. However, because there is more room for storage in room temperature it is therefore considered as a better alternative than refrigerator.

    Product three contains 2,6-Xylidine with a life time of one day. The sample storage rooms were the refrigerator and the freezer. Day two for the freezer did not fulfil the requirements while day six for the freezer met the requirements. Because of this inconsistency and uncertainty, the freezer should not be used as an option. Product three has therefore a prolonged life time of two days in the refrigerator.

  • Josic, Elma
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Provtagningsmetoder för mikroplaster i dagvatten och sediment2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Plastics have created the conditions for us people for decades because of its wide use. It has, however, resulted that there are amounts of microplastics in the environment and it is today an environmental problem that needs to be fixed.

    It is a challenge to clarify the origin of the microplastics, but it can be stated that artificial turf is one of the largest sources in Sweden and is expected to release several tonnes of microplastics. To find out how much microplastics an artificial turf can spread with stormwater, various samples are taken in eg. water and sediment environments.

    The purpose of this thesis was to present various sampling methods that can be used when sampling microplastics from artificial turf in water and sediment. Then, the results can be used as a basis for adapting future samples for microplastics in water and sediment. The following three goals were therefore set up; identify different sampling methods suitable for microplastics, compare these with each other and suggest appropriate sampling methods for microplastics from artificial turf in mainly water.

    For successful sampling, planning and preparation are required before the execution. This means that a concept model should be developed over how the soccer field is designed, where and when samplings should be performed, which parameters should be analyzed and that there are references for background contents, see figure 3, page 16. Information about the sampling location needs to be compiled, for example, which plastic materials are present in the artificial turf and which expected primary and secondary microplastics can be spread from the soccerfield.

    During this thesis, two sampling alternatives were identified to investigate microplastics in water samples:

    • Sampling of water (active sampling) for microplastic analysis

    • Sampling of filtrate (passive sampling) where microplastic is filtered. In this case, the microplastics that have been captured by the filter are analyzed.

    This thesis also deals with other samplings - sampling with pump, water-container and dredge. It is because to see which alternatives are available for water and sediment sampling and for obtaining a comparison between these samples.

    At sampling, there is currently no common standard for implementation, which would probably have facilitated the sampling work. Especially when the results were easier to compare with each other.

    A study visit was made at Bergavik's IP in Kalmar to perform sampling in three wells and in a nearby stormwater pond to drain the surface and drainage water from the artificial turf.

    The sampling began with the stormwater flow and the amount of rainfall during the previous days before the measurement was noted. All sampling occasions occur at similar weather and flow conditions. The water samples were then sent for analysis. This method can be repeated and after a few sampling occasions, a mean value of microplastic content can be obtained.

    The thesis conclusion is that it is important to look at how and where the sampling is performed. Both when it comes to active sampling and passive sampling, it is necessary to take samples taken on several occasions, describe the precipitation conditions before sampling, take samples at the same place and the same depth in order to more easily identify the amount of microplastics from the source and how much is then disseminated.

    The reason why it is today mainly active and passive sampling that is used in sampling microplastics from artificial turf is that these are proven methods. A suggestion for future studies is to identify a common standard for execution. It would facilitate analyzes of microplastic spread from artificial turf if the same standard was used everywhere.

  • Chung, Kevin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Effekten av gammastrålning på svällningskapaciteten för bentonitlera2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    SKB (Swedish Nuclear Fuel and Waste Management Company) is planning to store used nuclear fuel deep down in the bedrock, KBS-3 method. The repository will consist of 3 protective barriers, the copper canister, the bentonite clay and the bedrock. Bentonite clay has excellent barrier properties and is used to enclose the canister. The clay expands when it’s adsorbing water and has as function to act as a sealing material to prevent leakage of radionuclides. This work is focused on the gamma-ray effects on bentonite clays swelling capacity. The work is done in the department of Applied Physical Chemistry at the Royal Institute of Technology.

    Bentonite clay of the type Wyoming MX-80 and a total gamma-dose of 34,56 kGy with a Caesium-137 source where used in this work. To study the swelling capacity of bentonite clay, it was pressed to pellets with a dry density of 2260 kg/m3 and were put in into measuring tubes filled with deionized water. The swelling was documented with a camera.

    The results from the swelling capacity experiment showed no noticeable difference in swelling capacity between irradiated and nonirradiated clay.

  • Satof, Mostafa
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Al-asadi, Hasanain Hasse Hasson
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Modellering av rörliga laster: Jämförelse av resultat från influenslinje- och influensytametod från FEM-program2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    At present, the usage of FEM-programs becomes wider for loads effect calculation of bridges. Even though the calculation in all FEM-programs works following the same procedure, it differs when it comes to moving loads where we can identify two different approaches, ILM and ISM (influence line and influence surface method). ISM is used in FEM-programs that are most adapted for bridges where moving loads have great influence, while ILM is used in FEM-programs where moving loads are less important as house constructions. The aim is to evaluate the use of ILM programs (eg FEM-Design) when managing of moving loads in bridge and facilities contexts. This is achieved by comparing the results obtained from ILM programs with the results obtained from IYM programs. In addition, it will be checked how FEM-Design envelops the max and min values regarding (most adverse, conditional summation and unconditional summation). The comparison between those two methods was carried out using two different FEM programs based on different methods. Work carried out using FEM-Design (ILM program) and Brigade/Standard (ISM program). A platform bridge has been modeled and analyzed in both programs and a comparison between the results of both models has been performed. This comparison aims to investigate how ILM and ISM works when calculating moving loads and its influence in a bridge plate and in what way these two methods differ. to achieve comparable results between the programs, we examined different parameters and conditions. The thesis has shown which factors influenced the difference av results between FEM-Design and Brigade, and which summation methods that FEM-Design uses.

  • Haritidis, Panagiotis
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Tran, Tony
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Parameterstyrd modellering av bergtunnlar2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Project designing in the building construction industry has developed a lot during recent years and the result is that not only 2D documents are made, but also 3D models are created to facilitate the project. A problem most players are facing daily is when conditions and information in a project change and design engineers must make necessary changes to their models. These changes can be time-consuming, and the designers may need to do these changes more than once during the project. Could a parametric 3D model make these changes faster than a CAD model when conditions and information on a project change? One of the developers that frequently needs to make changes to its models is WSP geotechnical department. The desire is to find a new working method that increases the efficiency of project design of tunnels. The aim of this thesis was to try parametric modeling as a working method and to see if this method could be used to create ground tunnels. A script has been made in Grasshopper, a visual programming plug-in that generates a parametric model of a tunnel. The parametric model was then compared with an existing CAD model created by the WSP geotechnical department in an earlier project. Pros and cons have been presented and conclusions have been made about if parametric modelling could be more efficient than current working methods. The results of this thesis indicate that parametric modelling is an efficient working method and that it could be used as a working method for future ground tunnel projects.

  • Azad Ali, Bawan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Ahmadiyan, Sara
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Livslängdsdimensionering av korrosionsutsatta betongkonstruktioner2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Through history, iron has mainly been used as reinforcement in concrete. Contemporary building technology would not have been possible without reinforced concrete, however, from a global perspective, many concrete buildings have begun to encounter reinforcement corrosion, mainly due to chlorides and carbonation. When the chlorides come into contact with the reinforcing bars, a chemical reaction begins, which causes the iron to oxidize and begin to corrode. In a humid environment when the reinforcement corrodes, the iron expands and bursts the concrete from inside, which in turn results in cracks occurring in the concrete structure. In an environment with lack of oxygen, it often occurs that non expanding rust products form that are not defected on the concrete surface occurs through discoloring or spalling. This type of damage is not detected ocularly and therefore forms a more serious type of injury. This type of rust is a silent type of damage that can cause deteriorated bearing capacity in the construction, since the cross-sectional area of the reinforcement in the concrete decreases. Sweco has been involved in a couple of projects where there have been huge problems due to corrosion of reinforcement. The damages that emerged leading to the repairs of these type of damage costing large sums. This report is based on previous projects, articles, literature studies, reports and interviews. Interviews have been conducted with competent people who have shared their valuable opinions, knowledge and experiences. In order to stop ongoing corrosion of reinforcement and also repair the damage, several alternative solution and repair measures have been devolped. Some of the most relevant suggestions in this report is to remove the damaged concrete and then re-cast or alternatively cast in cathodic protection or a combination of these.

  • Nguyen, Duy
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Shu, Le
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Resurseffektivisering för ökad lönsamhet inom tryck & förpackning2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To be well prepared for the competitive market in commercial printing, today's companies must direct their production towards becoming more resource-efficient and profitable. It is known that the current market requires ever-increasing production capacity, but the customer is willing to pay less for the products. It is therefore critical that a company keep its productivity high and eliminate unnecessary losses in the production. 

    The purpose of this thesis is to investigate how resource efficiency affects the profitability of a company. The concept of key figures will be introduced and used primarily to measure and study profitability for a printing company. The project's work takes place in two phases. At first, a literature study, which is used to identify the most important key figures and study how they can be related to resource efficiency and profitability. The second phase involves a field study carried out at Eson Pac Ljungberg, a printing company that produces pharmaceutical packaging. The goal is to locate the largest assets and how they should be managed to extract the greatest possible profitability.

    There are many ways to measure and benchmark the performance of a production line. Today's technology provides opportunities to perform complex measurements using computer sensors and telecommunication equipment. However, the challenge is to apply these metrics and use them in practical implementation. All employees in the company must take part in these measurements and understand how they can be used to improve production. These metrics are turned into key figures when a company has successfully found a method of merging its production strategy with the metrics. The method is based on choosing the most relevant metric, considering the company's objectives. The company will then set up an effective communication channel where the management and manufacturers can quickly exchange information about the production and feedback quickly when errors and changes occur.

    The result shows that the main resources that contribute to increased profitability are materials, equipment and personnel. By compiling the key figures and an example measurement of OEE value (Overall Equipment Effectiveness), it is shown that low utilization of resources can have negative consequences for profitability. Field study at Eson Pac AB shows that the company's management has an active list of key figures and objectives that they are constantly working towards. The company, on the other hand, shows deficiencies in following up their key figures, since communication between management and production staff lacks mutual understanding of eachother's tasks and many of the key figures are not used to their full potential. Eson Pac AB formulates its key figures mainly according to the customer's perception, unlike the versatile factors of the literature study. Customer relationship seems to be the company's focus and has a great impact on the company's view of resource access. The two key figures that the company agrees with the literature review are delivery precision and customer complaints, i.e. the two main key figures to indicate customer satisfaction.

  • Ronnedahl, Simon
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Åström, Sophie
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Resurseffektiv produktion i tillverkande företag: Ur ett hållbarhetsperspektiv i en kvalitativt hantverksproducerande verksamhet2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The increasing global population in combination with finite resources places demands on how resources are used. Mass production was a consequence of the assembly line introduced by Henry Ford in manufacturing processes, and in order to enable product variation, Toyota developed the production process by introducing the Toyota ProductionSystem and Lean Production, which focuses on reducing waste. The concept of Lean Retail is becoming increasingly common in the retail industry, where the benefits of the concept are being implemented in business strategies and manufacturing processes. Cradle to Cradle (C2C) and circular economy are inspired by nature’s own cycles, and concerns eliminating waste.

    The purpose of this report is to evaluate how a high-quality manufacturing company, which mostly works with craftmanship, has implemented its own sustainability philosophy and to what extent they work with the Lean Retail concept. The company is Svenskt Tenn, and an interview with production and quality manager Johanna Asshoff in combination with a visit at one of their subcontractors is the basis for the empirical study. In combination with that, a literature study was carried out with the help of KTH’s databases, which concerns the topics sustainability, Lean production and circular economy.

    As a company, Svenskt Tenn has a clear picture of how they work with their sustainability philosophy. In their own book, ”Svenskt Tenns hållbarhetsfilosofi”, several different dimensions are presented by the company and it is also mentioned that the C2C philosophy has been implemented throughout the process by their linen supplier. There is a sustainability focus behind many of the company’s strategic decisions and since the company has been active for many decades, they have also been involved in how sustainable development and the climate issue have been dealt with over time. As a consequence, they have faced a number of challenges regarding their production process, and they constantly ask themselves the question ”What is sustainable after all?”. Cooperation with subcontractors is long-term and important, and the preservation of crafts is the main focus. Manufacturing processes and selection of materials are carefully evaluated – There is a thought behind every decision.

  • Vaseigaran, Ajanth
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Khan, Areeba
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Hur används datoriserade beställningssystem på frukt- och gröntavdelningen i livsmedelsbutiker för resurseffektivisering?2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis covers how automated ordering systems are used within the department in grocery stores that account for the largest share of waste in relation to the quantity delivered, i.e. the fruit and vegetable department. In this report, the term automated ordering system is defined as a system that can collect data on the amount ordered, sold and wasted, and based on that automatically put new orders. The purpose was to determine how resource-efficient the system is. The resources we focused on were staff, money, time, energy and inventory.

    The study was conducted using a literature study, personal communication with Whywaste and visits to four different grocery stores where the managers of produce department were thoroughly interviewed. Based on the results of the interviews, it was concluded that automated ordering system saves both money and time. The workload on the staff is facilitated and more energy can be spent on creating value for the customers. For example, focusing more on the appearance of the fruit and vegetable department, as the structure and quality of the goods are of great importance. The system also helps new staff to adapt by making it easy to order according to statistics. Some suggestions on how the automated ordering system could be improved have been presented in the report, such as having a scale under the inclined shelves to get the weight in real time.The report also draws attention to automated grading system, a system that classifies the degree of maturity of fruits and vegetables, as well as Whywaste computerized solution for the management of date-labeled goods.

  • DALLA ROSA, LEONARDO
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Structural Health of a concrete tunnel lining under complex in situ loading2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Supporting structures were designed for a utility tunnel in hard rock which was to be intersectedby some road tunnels. With the intersections involving partial overlapping between the idealcross-sections, a concrete lining and post-tensioned steel cables were added to support theutility tunnel prior to the excavation of the road tunnels. The objectives in this work wereto identify the structural behaviour of the system, assess the present state of the supportingstructures and suggest an effective monitoring strategy. Preliminary information was collectedfrom the original drawings, technical specifications as well as from site visits. Using on thefinite elements software Comsol Multiphysics, suitable models were built to represent thetunnel intersections and to test hypotheses. The significant uncertainties in the problem wereaddressed by studying limit cases and discussing their results. A measure of validation wasgained from comparing cracks in concrete on site with cracking hotspots predicted by themodel. It was concluded that the behaviour of the lining is not compatible with that of cablesuspended structures and that concrete is subject to relatively high state of stress. Monitoringcable forces was found to be an ineffective strategy for identifying changes in the structuralsystem. Monitoring the evolution of cracks in concrete was found to be the most feasiblestrategy.

  • Hallak Neilson, John Peter
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Numerical and experimental dynamic analyses of the Vega Pedestrian bridge including seasonal effects2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As timber structures become increasingly relevant and sought after – since they enable improvements in building time while reducing a structure’s life cycle impacts – streamlining their design can have meaningful economic and environmental implications. For timber footbridges, its design is frequently governed by serviceability criteria linked to excessive vibrations. To address this in design, it is necessary to correctly characterize the structure’s dynamic properties and understand what the leading parameters in its behaviour are. This thesis studied an existing timber arch footbridge, aiming to evaluate its dynamic behaviour both with experimental measurements and with theoretical models. The influence of temperature change over different seasons was considered, particularly around its effect on the asphalt layer – whose stiffness is highly correlated to temperature. The experimental results showed high correlation between temperature and natural frequencies: a variation of +21°C reduced the natural frequency for the 1st transverse mode of the deck by as much as 30.6% while the 1st vertical mode was reduced by 17.7% (variation of 0.029Hz/°C). The damping ratio was also measured, though a definitive correlation between its value and temperature was not identified. This change in behaviour cannot be explained by the influence of the asphalt layer alone however, as there is a high degree of uncertainty around many other components of the bridge and their interactions, such as the connections. Thus, to fully characterize the influence of each component with changing temperature, further experimental tests would have to be performed, or simpler structures with fewer connections should be considered. In designing a new structure, considering the asphalt layer as an added mass is a straightforward way to treat this material at the most critical condition (i.e. no contribution to stiffness). This strategy lead to sufficiently similar results between the computational model and the experimental results at warm temperatures. The asphalt stiffness could perhaps be considered for the 1st transverse mode of the deck, since it is in this mode that the asphalt layer plays its largest contribution.

  • Arnestrand, Frida
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Nilsson, Stina
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Hur används operatörens kunskap ochkompetens för utveckling av produktionen?2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    An important part of the Lean production system is the elimination of waste of various kinds. One of these wastes is unused creativity and competence, which was also the basis for this report and we landed in the issue "How is the operator’s knowledge and competence handled in development of the production?". The work is based on a literature study of knowledge management and Lean principles, as well as interviews with an operator and production manager at Scania and Sandvik Coromant.

    Theory shows that there are a variety of ways to look at knowledge and how it is handled in the best possible way. This theoretical subject is called knowledge management and discusses different ways of approaching knowledge transfer and management in business. The subject is based on the fact that there are two ways of looking at knowledge, as an object or as a process linked to action. There is also two kinds of knowledge, explicit which is concrete knowledge such as an instruction and implicit knowledge which ispersonal knowledge and often comes from experience.

    Both Scania and Sandvik Coromant are currently incredibly proficient in knowledge transfer and working with Lean, which is evident through their well established methods and systems. They both have a great focus on improvements and let no deviations pass without discussion. Employees are highly involved in the companies and are given opportunitiesto influence and develop their workplace. Scania and Sandvik Coromant use different methodsto attempt to gather and save implicit knowledge from their experienced employees, but it is a challenge.

    The analysis shows that the knowledge management depends on many different parts ofthe production. In summary it is about the understanding of knowledge, good leadership, well functioning teams and the usage of knowledge management tools. The knowledge that the companies manages to capture is currently used to improve the working environment and safety, but also to develop the companies and keeping them competitive.

  • Lind, Annakarin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Moberg, Caroline
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Hållbar produktion inom mejeriproducerande företag: En studie av hållbarhetsarbetet hos ett mejeriproducerande företag i Sverige2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Sustainable development is a notion that is always present in the society, but in recent times has become more in question due to the increased awareness of the earth’s limited resources. An area sustainable development can be applied to is sustainable production; sustainable production within companies producing physical products. This work studies the sustainable development work within a dairy producing company in Sweden; Skånemejerier. The purpose with the study was to investigate how the work of sustainable development is carried out and valued within one of the greatest dairy producing companies in Sweden, and compare this to how sustainable development is carried out in conventional milk production.

    The work was accomplished through a literature study of sustainable production within the food industry, conventional milk production, and sustainability as a term, and how Sweden in general works with sustainability. A case study of how the sustainable development work looks like in Skånemejerier was then carried out based on, among other things, the latest sustainability report of Skånemejerier. Also an interview with the environmental coordinator of Skånemejerier was done. At last the sustainability work within Skånemejerier was compared to how sustainability is valued and present in conventional milk production, and the material that came up was then analyzed with respect to sustainable development.

    The result that rose through the investigations was that Skånemejerier has a strong focus on sustainability in their milk production. They work actively with a selection of the UN's global sustainability goals and has also come in fifth place of sustainable trademarks in the food industry in Sweden. Skånemejerier works with all the areas that are judged as risk areas within conventional milk production. They follow up their sustainability work continuously and also creates own goals and detailed plans of how they are going toachieve the global sustainability goals.

    Even though Skånemejerier has a strong focus on sustainability there is always room for improvement; suggestions of further implementations to increase the sustainability in their production could be cooperation with other dairy producing companies with the purpose to reduce the overall transports in Sweden. Another implementation is to investigate the sustainability work even more in the beginning of the food supply chain for the milk; that is, within the farming. It can also be discussed whether the dairy producing companies in Sweden should perhaps localize their selling more locally to reduce transports. Another perspective is whether milk production is to be promoted at all. Milk is not essential for the majority of the population and in some cases it could be replaced with herbal foods. There are both advantages as well as disadvantages with milk production from a sustainability view. However, since it is complicated to completely erase the milk production, due to human psychology, it is relevant to instead investigate possible improvements to increase the sustainability work within productions.

  • Fredstrand, Victor
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Hanna, Yacoub
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Vilka metoder och mätetal som företag använder sig av för att utveckla sin befintliga resurseffektivitet2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    As a consequence of the rapid technology development around the world, large manufacturing companies in Sweden face great challenges in order to keep up with development, and to compete with others. Achieving a resource-efficient production is one of the biggest challenges that companies strive to achieve. The purpose of this thesis is to answer the question "What methods and measures is used by companies to develop their existing resource efficiency?” It was done by first making a broad research about the particular subject in order to find scientific articles and thereafter all the information was narrowed down. In addition, two case studies was executed at Scania and Octapharma to investigate what types of methods and measures they use. The results of the interviews at the two companies were to be compared withthe findings in the scientific articles to see how they complete each other. The thesis provided the following results: The different parts within Lean is practiced as methods in order to achieve a resource-efficient production in the companies that were interviewed and in the selected scientific articles. There is a correlation between the size of a company and its ability to fully implement Lean. A larger company is usually able to implement Lean to a larger extent than a smaller one. OEE and OPE are two measures that were used by Scania, while Octapharma did not use any measures because they measure the efficiency manually. Moreover, communication is a necessary factor in order to achieve a efficient production. The size of the company has an impact on the level of the communication as well. A larger company has a better overall structure and puts in more time and resources to make the communication as effective as possible.

  • Björgvinsdóttir, Linda
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Reconstruction of Fall Injuries for Children of Different Ages2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The idea to use finite element (FE) models to reconstruct accidents for humans is becoming more popular the last years. They represent the human body very accurately and indicate well changes in shape, size and biomechanical properties. FE models are useful when looking at complex factors in the human body in a more systematic way and when the approach is too complicated for conventional setups.

    Positioned child models from PIPER were used in the process and then rotated in LS-PrePost according to impact points and impact velocities from a given literature data where information from witnessed fall accidents of children was given. The simulations were finally run in LS-Dyna and the purpose was to investigate if the resulting brain injuries were similar to the real life data.

    From the literature, the falling distance from lowest point of the body to the ground, the age of the child, gender, type of ground and results from CT scans were all known. To compare the results to the literature data, section cuts of the brain were taken at four locations with different time steps. Biomechanical injury predictors such as brain strain, acceleration, rotational angular acceleration and rotational angular velocity were observed and helped with the comparison.

    In total, 12 cases were reconstructed which ended as 22 simulations. Due to uncertainty regarding the falling height when the children fell from a swing, each swing case had 3 scenarios. Overall the comparison of predicted injury locations from LS-Dyna to real injury locations from CT scans indicated that 7 out of 12 cases compared relatively well. The comparison of a 23-month-old girl to the same case reconsructed with CRABI-18 showed similar outcomes of the angular acceleration and the angular velocity. The linear acceleration and HIC were however much higher with LS-Dyna. Comparison between the swing cases of a 10-, 12- and 13-year-old resulted in similar results for the 12- and 13 year-old girls but the 10 year boy had lower values for all biomechanical parameters except the angular velocity which was a bit higher.

    With more detailed information about real accidents and precise scaling of PIPER child models, reconstruction with LS-Dyna could be useful in the future to design safer playgrounds for children and to obtain injury criterion for children after fall incidents.