<p>The massive number of injuries sustained in trafficaccidents is a growing problem worldwide, especially indeveloping countries. In 1998, more than one million peoplewere killed in traffic accidents worldwide, while about tentimes as many people were injured. Injuries to the centralnervous system and in particular to the headare especiallycritical to human life. This thesis contains five researchpapers looking at head injuries and head protection, proposingnew and more efficient ways of protecting the head, especiallyin traffic accidents.</p><p>In order to define the national dimensions of the patternsof injuries incurred in motorcycle and moped accidents inSweden, a statistical survey was performed on data spanning a13-year period (Paper A). In Sweden, 27,100 individualsreceived in-patient care for motorcycle and moped accidentinjuries between 1987 and 1999. The motorcycle and moped injuryrate reduced in the second half of the study period, so toowere the total number of days of treatment per year. Males hadeight times the incidence of injuries of females. Head injurieswere the single most frequent diagnosis, followed by fracturesof the lower limbs. Concussion was the most frequent headinjury. These statistics clearly show the need for better headinjury prevention systems.</p><p>According to the statistics, the most common type of impactto the head in motorcycle and moped accidents is an obliqueimpact. Oblique impacts generate rotations of the head, whichare a common cause of the most severe head injuries. Thereforea new test rig was constructed to reproduce oblique impacts toa helmeted dummy head, simulating those occurring in real lifeaccidents (Paper B). The new test rig was shown to provideuseful data at speeds of up to 50 km/h and with impact anglesvarying from purely tangential to purely radial. Thisinnovative test rig appears to provide an accurate method formeasuring accelerations in oblique impacts to helmets.</p><p>When testing the performances of motorcycle helmets,discrepancies are usually seen in the test results. In order toevaluate these discrepancies, the finite element method (FEM)was used for simulations of a few oblique helmet impacts (PaperC). Amongthe parameters studied, the coefficients of frictionbetween the impacting surface and the helmet and between thehead and the helmet had the most significant influence on therotational accelerations. Additionally, a thinner andconsequently also weaker shell and a weaker liner, providedbetter protection for the impacts studied.</p><p>Since there are no generally accepted global injurythresholds for oblique impacts to the human head, a study wasdesigned to propose new injury tolerances accounting for bothtranslations and rotations of the head (Paper D). In thatstudy, FE models of (a) a human head, (b) a Hybrid III dummyhead, and (c) the experimental helmet were used. Differentcriteria were proposed for different impact scenarios. Both thetranslational and the rotational effects were found to beimportant when proposing a predictor equation for the strainlevels experienced by the human brain in simulated impacts tothe head.</p><p>In order to reduce the level of head injuries in society andto better understand helmet impacts from different aspect, aballistic impact was also studied (Paper E). The effects ofdifferent helmet shell stiffness and different angles ofimpacts were simulated. In this study, the same FE head modelfrom Paper D was used, however here it was protected with amodel of a composite ballistic helmet. It was concluded thatthe helmet shell should be stiff enough to prevent the insideof the shell from striking the skull, and that the strainsarising in the brain tissue were higher for some obliqueimpacts than for purely radial ones.</p><p>In conclusion, this thesis describes the injury pattern ofmotorcycle and moped accidents in Sweden. This thesis showsthat the injuries sustained from these accidents can bereduced. In order to study both translational as well asrotational impacts, a new laboratory test rig was designed. Byusing the finite element method, it is possible to simulaterealistic impacts to the head and also to predict how severehead injuries may potentially be prevented.</p>

Överums Bruk AB tillverkar jordbruksmaskiner såsom konstgödselrampspridaren Wing Jet. Wing Jet har idag en konstgödselbehållare tillverkad i rostfritt stål och företaget önskar veta om det är möjligt och lämpligt att tillverka behållaren i plast/plastkomposit i syfte att minska produktionskostnaden av behållaren samt dess vikt. Detta arbete är begränsat till behållaren, övriga konstgödselspridaren ska inte behöva några förändringar för att byta den rostfria behållaren till en i plast/plastkomposit och det ingår inte i arbetet att tillverka en prototyp. Rotationsgjutning och handuppläggningsmetoden (glasfiberarmering) är två tillverkningsmetoder som är lämpliga att använda vid tillverkning av så stora objekt. Simuleringar av en rotationsgjuten behållare i materialet högdensitetspolyeten (HDPE) i programmet SolidWorks Simulation Standard resulterar i maximala effektivspänningar strax över materialets brottgräns då ett tryck baserat på ekvationer från europastandarden Eurocode 1-4: 2006 (Silor) anläggs på behållarens insida. Det uppstår dock deformationer på flera centimeter vilket i sig inte är ett problem, men det gör behållaren mindre estetiskt tilltalande (släta sidor buktar utåt). Behållarens vikt minskar till ca hälften av dagens och den är billigare att tillverka. Material och tillverkningsmetoder som resulterar i en behållare med högre styvhet i avseende att minska deformationen är rekommenderat att undersökas som vidare arbete. Exempel på detta är glasfiberarmerad polyester eller epoxi och ”sandwich”-konstruktioner. En sandwich-konstruktion består av två (eller fler) lager av ett material med en kärna, av t.ex. ett skum, mellan. Genomförda simuleringar är linjärelastiska, medan plaster allmänt är olinjära, så olinjära simuleringar bör genomföras innan prototyp tillverkas. / Överums Bruk AB manufactures agricultural equipment such as the fertilizer spreader Wing Jet. Wing Jet has a container which today is manufactured from stainless steel and the company wishes to know if it is possible and suitable to manufacture the container from plastic/plastic composite with the purpose to lessen the containers production costs and weight. This work is limited to the container, the rest of the fertilizer spreader should not need any changes to switch the stainless steel container for a plastic/plastic composite one and the work does not include manufacturing a prototype. Rotational molding and hand lay-up (glass-fibre reinforcement) are two manufacturing processes which are suitable to use when manufacturing such large objects. Simulations of a rotational molded container in the material high density polyethylene (HDPE) in the program SolidWorks Simulation Standard results in maximum effective stresses just above the materials tensile strength when a pressure based on equations from the European standard Eurocode 1-4: 2006 (Silos and Tanks) are applied on the containers inside. However, deformations of several centimeters occurs which in itself is not a problem, though it makes the container less esthetically appealing (smooth sides bulges outward). The containers weight decreases to approximately half of that of today and it is cheaper to manufacture. Materials and manufacturing processes which results in a container with higher stiffness in the purpose of lessen the deformation is recommended to investigate as future work. Examples of this are glass-fibre reinforced polyester or epoxy and “sandwich”-constructions. A sandwich-construction is comprised of two (or more) layers of a material with a core, of e.g. foam, between. The simulations carried out are linear elastic, whereas plastics generally are non-linear, so non-linear simulations should be carried out before a prototype in manufactured.

Kantvikmaskin FUTURA PLUS 30 klarar idag att bocka en stålplåt, arbetsstycke, som är 3000 mm bred och 3 mm tjock med en acceptabel variation av bockradien. Målet med detta förbättringsarbete är att styvheten för de längsgående maskindelarna ska ökas, så att det är möjligt att bocka ett arbetsstycken som är 20 % tjockare än vad som är möjligt med dagens konstruktion. Genom att öka styvheten skall maskinen kunna hantera arbetsstycken av stål med en bredd upp till 3000 mm och en tjocklek upp till och med 3,6 mm med bibehållen variation av bockningsradie. Ökad styvhet innebär också att arbetsstycken med mindre tjocklek än den maximala kan bockas med större noggrannhet än dagen konstruktion. Detta kan leda till en större marknad för maskinen då kraftigare produkter eller produkter med en högre noggrannhet kan tillverkas med denna typ av maskin. Genom att optimera materialåtgången för maskindelarna minskas materialkostnaderna. Begränsningar i studien är att tillverkningskostnaden hos längsgående maskindelar skall förbli den samma som i dagens konstruktion. Genomgång av tidigare forskning gjord inom ämnet plåtbockning visar att erforderliga momentet för bockning kan beskrivas med hjälp av balkteori. Det konstateras att, enligt den linjärelastiska-idealplastiska materialmodellen, bockningsmomentet är proportionellt mot tjockleken i kvadrat för en balk. Detta samband används till en jämförelse mellan dagens maskinkonstruktion och en maskinkonstruktion som ska klara 20 % tjockare arbetsstycken. Detta samband och att deformationerna hos maskindelarna är linjärelastiska leder till att enhetslaster används. Studier av över- och under-prismorna visar att viss deformation kan avhjälpas med nya konstruktionsplåtar där en fotplåt för underprismat är det som mest reducerar deformationerna per viktenhet. Det slutgiltiga dimensioneringsförslaget leder till att maskindelarnas totala vikt minskas samtidigt som styvheten ökas till att klara 20 % tjockare arbetsstycken. Dock ökas antalet konstruktionsplåtar vilket kan leda till ökad produktionstid.

This thesis investigates the use of a combined finite element and perfectly matched layer approach in modeling guided elastic wave motion in infinite plates and cylinders and its potential applications to non-destructive evaluation. Underlying principles of the per-fectly-matched, absorbing layer are demonstrated on one-dimensional wave propagation in a semi-infinite elastic rod. Feasibility of using the perfectly matched layer as absorbing boundary condition in the finite-element modeling of guided elastic wave propagation and scattering is studied for the canonical problem of shear horizontal wave motion in isotropic plates. Numerical re-sults in this study are validated against exact analytical solutions. Excellent agreement has motivated the endeavour to take the technique to the next level of pressure, shear-vertical wave motion in isotropic and transversely isotropic plates. Time-domain, finite-element formulation of the perfectly matched layer for pressure, shear-vertical wave motion was validated through comparisons with semi-analytical lit-erature data and reciprocity checks. Numerical implementation of the model was em-ployed in studying the effect of crack presence on the time of arrival in a pitch-catch, non-destructive inspection arrangement. Predictions made confirmed previously-reported experimental findings. Extensions into three-dimensional, Cartesian and cylindrical spaces were validated against reported data. Practical examples of wave scattering in damaged concrete beams, oil and gas pipelines, and composite shells demonstrated the potential use of the proposed model in simulating elastic-wave based non-destructive inspection. Up to 80 % of the computational time needed to run an extended-mesh, finite-element model can be saved by introducing the perfectly-matched, absorbing layer to the finite-element model as the current thesis proposes. This significant saving in computational time by the proposed FE-PML model can accelerate the production of artificial neural network training data or help tackle complicated non-destructive testing applications.

En ny metod för montering av diskbänkar har tagits fram av företaget Furhoffs Rostfria AB i Skövde. Metoden innebär en mer effektiv montering, dock är förflyttningen av material fram till monteringsplatsen en flaskhals. Målet med detta arbete är således att utveckla ett förslag på en konstruktionslösning för materialhantering. Huvudmålet kompletteras även med mer specifika mål som bör uppfyllas för en optimal lösning, innehållande mål för antal arbetsmoment, användningstid samt uppfyllnad av allmänna krav från Arbetsmiljöverket och krav angående hållbar utveckling. Som utgångspunkt för att förstå de funktioner som konceptförslaget bör ha och för att förstå de ingående parametrarna utförs en litteraturstudie. Studien använder sig av en bred bas av källor där aktuella vetenskapliga artiklar står som bas för metoden för hållbar utveckling, tekniska böcker samt webbkällor bygger upp övriga metoder och befintlig kunskap från företaget vävs också in. Lösningen på problemställningen innefattar fyra funktioner som ett konceptförslag ska utföra. Att transportera, lyfta och hålla de ingående delarna samt att ha ordning bland de placerade detaljerna är dessa fyra funktioner. Olika grundkoncept tas fram genom tre olika konceptgenereringsmetoder där olika kompetenser inkluderas. En viktad konceptvalsmatris används för att välja ut vilket koncept som fortsatt ska analyseras. Det vidareutvecklade konceptet granskas efter risken att välta, risken att pålastade saker glider och granskning av hållfasthetsegenskaperna hos konstruktionen. Hållfasthetsanalysen med finita element-metoden utvärderar verkande moment, effektivspänningar samt deformationen av konstruktionen. Konstruktionen analyseras med en modell bestående av balkelement och en modell bestående av skalelement. Slutsatsen av analyserna är en, inom användningsområdet, obetydlig deformation samt en knapp tvåfaldig säkerhetsfaktor av spänning mot materialets sträckgräns. Konceptförslaget uppfyller alla uppsatta mål samt krav och antas vara en bra lösning på problemställningen. Förslag på framtida förbättringar av konceptförslaget tillhandahålls. / The company Furhoffs Rostfria AB located in Skövde has developed a new assembly method for kitchen-sinks. The method means a more effective assembly of kitchen-sinks but the transportation of the material to be assembled is still a moment requiring a lot of time. The goal of this work is to develop a material handling concept that facilitates this transport. To confirm the achievement of the set goal, a number of more specific goals are also set. These goals should be achieved for the most optimal solution regarding the number of work moments, time regarding usage, general requirements from the Swedish Work Environment Authority and requirements regarding sustainable development. To understand the functions that the concept should fulfill and to understand the ingoing parameters, a literature study is performed. The study is based on a number of sources including current scientific articles which represents the foundation regarding the method for sustainable development. Web sources, books with technical character and knowledge from Furhoffs Rostfria AB are used as a foundation for the remaining methods performed. The final concept satisfies four functions, to transport, to lift, to hold and to assort ingoing material. Different basic concepts are produced by using three different methods of generation of concepts, where different competences are included. A weighted concept selection matrix is used to select which concept that should be analyzed further. The chosen concept is analyzed regarding; the risk of tipping, items placed on the concept sliding around and the strength and the mechanics of the concept. The material strength analysis, performed by using the finite element method, evaluates acting moments, acting effective stresses and deformation of the concept. The concept is evaluated by creating a beam element analysis and by creating a shell element analysis. The conclusion from these analyzes is that, regarding the practical usage of the concept, an insignificant deformation is obtained. Regarding occurring effective stresses a safety factor of barely two is obtained compared to the yield limit of the chosen material. The concept fulfills all the goals and demands set and is evaluated as a functioning solution for the stated problem. Suggestions regarding further future improvements for the chosen concept are provided.

This thesis investigates the use of a combined finite element and perfectly matched layer approach in modeling guided elastic wave motion in infinite plates and cylinders and its potential applications to non-destructive evaluation. Underlying principles of the per-fectly-matched, absorbing layer are demonstrated on one-dimensional wave propagation in a semi-infinite elastic rod. Feasibility of using the perfectly matched layer as absorbing boundary condition in the finite-element modeling of guided elastic wave propagation and scattering is studied for the canonical problem of shear horizontal wave motion in isotropic plates. Numerical re-sults in this study are validated against exact analytical solutions. Excellent agreement has motivated the endeavour to take the technique to the next level of pressure, shear-vertical wave motion in isotropic and transversely isotropic plates. Time-domain, finite-element formulation of the perfectly matched layer for pressure, shear-vertical wave motion was validated through comparisons with semi-analytical lit-erature data and reciprocity checks. Numerical implementation of the model was em-ployed in studying the effect of crack presence on the time of arrival in a pitch-catch, non-destructive inspection arrangement. Predictions made confirmed previously-reported experimental findings. Extensions into three-dimensional, Cartesian and cylindrical spaces were validated against reported data. Practical examples of wave scattering in damaged concrete beams, oil and gas pipelines, and composite shells demonstrated the potential use of the proposed model in simulating elastic-wave based non-destructive inspection. Up to 80 % of the computational time needed to run an extended-mesh, finite-element model can be saved by introducing the perfectly-matched, absorbing layer to the finite-element model as the current thesis proposes. This significant saving in computational time by the proposed FE-PML model can accelerate the production of artificial neural network training data or help tackle complicated non-destructive testing applications.

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Purpose: The purpose of this study is to analyze the application of sensory marketing in malls. Problem discussion: The competition between malls is increasing, where visitors are increasing demands on the shopping malls layout. Shopping malls surface and its atmosphere becomes essential in the design of a mall so it will be attractive enough. Sensory marketing can be an appropriate method to stand out from the crowd and attract visitors. Sensory marketing is a process of engaging visitor’s senses to create a strong relationship between the brand and visitors. When the five senses are stimulated it creates a relationship with the brand on more levels, which in turn contribute towards that the customer is willing to spend more money on the brand. Theory: The theory includes a presentation of sensory marketing, the human five senses: hearing, sight, touch, smell and taste, brands and a model of the holistic pentagon. Method: The study is both quantitative and qualitative. A triangulation will be applied consisting of interviews, survey and observations. The data were analyzed using selected theories. Results and conclusion: The result of the paper shows that sensory marketing, stimulation of the human five senses contribute to an increased positive attitude towards the brand. Application of sensory marketing is therefore a good way to differentiate itself from competitors.

Industries, such as the automotive industry, aim to increase the reliability of their products to match the demands and assure the safety of their clients. The proposition of a third generation advanced high strength steel is introduced in this study. The ideas surrounding the behavior of transformation induced plasticity (TRIP) steels and particle reinforced composites are combined and investigated. A finite element model (FEM) is created to investigate the effects of dispersed ceramic particles with varying parameters throughout a TRIP steel microstructure and identify key mechanisms responsible for achieving simultaneous enhancements in strength and ductility. The ceramic material utilized and volume fraction of the ceramic particles dispersed throughout the representative volume element (RVE) are the two varying parameters investigated in this study. Through observing the equivalent plastic strain (PEEQ) distribution at different strain levels up to 100%, evidence of failure controlled by strain localization throughout the ferrite matrix is more prevalent through the softer, austenitic microstructures with 5% or less ceramic particle inclusions. On the other hand, the presence of the hard martensite constituents, or 10% volume fraction of ceramics in an austenitic structure, proposed that failure would engender due to void nucleation at the harder constituent/ferrite interfaces. These voids will then grow and coalesce throughout the microstructure, resulting in a crack. The increased addition of ceramic inclusions also illustrates a simultaneous enhancement in the ultimate tensile strength and ultimate strain in all microstructures. Tensile strength increases by a total of 18% with 10% volume ceramic particles in a TRIP steel microstructure. Between utilizing silicon carbide, cementite, zirconia and aluminum oxide ceramic particles, the microstructure that illustrated the most optimal enhanced performance in strength and ductility was the 10% volume fraction aluminum oxide particle reinforced TRIP steel composite.