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57 Uppsatser om Tensile stiffness - Sida 2 av 4

Undersökning av energiförbrukning och konceptutveckling av mer energisnåla frukostmaskiner

This master thesis comprises analysis and dimensioning of a keyed joint between a generator axis and a hub with aid from the FEM-software ANSYS Workbench 13.0.The generator axis is a part of a hydroelectric power station that generates electricity with a reactions turbine, a Kaplan turbine. The existing keyway consists of one parallel key with the width 90 mm and height 45 mm. Due to a planned increase of the power of the generated power with 32 % a design study was needed to see if the keyed joint would be suitable for the extra force. Because of the fact that the axis diameter is bigger than the standards covers/recommends a the keyway had to be re-dimensioned. In an earlier assignment from Skellefteå Kraft AB to Sweco Energuide the keyway was planned to be properly dimensioned, but no final solution was approved.During this master thesis a number of different numerical tests were made.

Vegetarisk kost - ett möjligt behandlingskomplement för symtomlindring vid reumatoid artrit?

Sahlgrenska Academyat University of GothenburgDepartment of Internal Medicine and Clinical NutritionAbstractTitle: A vegetarian diet, a possible treatment complement for relief of symptoms ofrheumatoid arthritis? A systematic review.Author: Alexandra Ahlsén and Caroline ForsbergSupervisor: Mette AxelsenExaminer: Anna WinkvistProgramme: Dietician study programme, 180/240 ECTSType of paper: Examination paper, 15 hpDate: May 22, 2012Background: Rheumatoid arthritis (RA) is a chronic remitting polyarthritis that is relapsing.Symptoms are inflammation of the joints with pain, stiffness and degradation of joint tissue.In some cases, also other parts of the body are involved. The treatment consists ofmedications to reduce pain, inflammation and degradation of joint tissue. Today, the offerednutritional treatment is primarily focused on meeting energy requirements and nutrient needs.The diet has also been discussed as symptomatic treatment, and one of the factors believed toinfluence the symptoms is meat.Objective: To assess the evidence as to whether a vegetarian diet affects the symptoms ofrheumatoid arthritis, and if so, to suggest how it can be implemented in practical dieteticswork.Search strategy The databases used in the literature search was PubMed, Scopus, and AMED.The search words used were: "rheumatiod arthritis", "vegetarian", "vegan", "diet", "meat" and"animal protein".Selection criteria: Studies investigating a vegetarian diet on the symptoms of RA wereincluded. Only RCT, clinical trial, controlled clinical trial, human studies and original articlesin English or Swedish were included.

Jämförelse mellan olika träbjälklag

Wooden joist slabs is a common type of floor in residential buildings. Higher demand and production of residential buildings increases the possibilities of profiting by optimizing the system of joists in a variety of areas. Spring and deflection is something most people can relate to since it?s not that uncommon to hear furniture rattle when you walk over a wooden floor. To remove the presence of those kinds of vibrations the system of joists have to be made stiffer than the standard joist construction that is used in today?s constructions.

Abrasiv nötning av polymerer tillverkade genom 3D-skrivning

Volvo Cars in Skövde manufacture and assemble Volvo engines. When attaching the ignition coil to all 4-cylinder engines, a special mounting tool is required. This mounting tool is currently manufactured from injection-molded polyoxymethylene (POM), a thermoplastic. It has been noted that the life span of the tool is shortened as a result of abrasive wear that occurs during the attachment process of the ignition coil.An investigation of the possibility of manufacturing the mounting tool with a 3D-printer is undertaken in cooperation with ÅF, a consultant to Volvo Cars. A literature study is first presented to introduce broader knowledge on the subject.

Provning av ythärdade material tänkta för
transmissionsdetaljer

This technical report describes the master thesis in material engineering called ?Testing of surfaced hardened materials conceivable for gears and shafts?. The work extents 20 academic points. Land systems Hägglunds manufactures and sells different kinds of combat vehicles and terrain vehicles. Since the demands for bigger and stronger vehicles increases all the time, so are the demands on shafts, gears and other transmission details.

Elasticitetsmodulen i en kalkstabiliserad vägterrass : en fältstudie

Stabilization of subgrade is an internationally common technique to improve the characteristics of a soft soil. Improving the stiffness and bearing capacity of the subgrade enables the pavement to be designed with reduced depths of subbase and basecourse aggregates. This makes the stabilization technique both economically and environmentally interesting. Both natural and stabilized soils have high inherent property variability that should be considered when the characteristic value is derived. By analyzing the spatial variability in stabilized and natural subgrades it is possible get the parameters needed for reliability?based modeling of soil properties.

Ljusspridningsvariationer i finpapperstillverkning

The purpose of this Master's thesis is to find possible explanations of variation in light scattering in a fine paper. Samples were collected from each second tambour during a time period of two weeks from a paper machine at MoDo Paper, Husum. Two data sets, consisting of 20 and 95 observations, were selected for extensive analysises of tensile and structual properties. The data was evaluated with multivariate data techniques using the programs Simca and Extract. The results of PCA- and PLS- analysises pointed out 3 of 52 variables as important for the variations in light scattering.

Inverkan av tvång i gjutfogar och i betongkonstruktioner på
elastiskt underlag: Influence of Restraint in Casting Joints
and in Concrete Structures on Resilient Foundation

In this report, the risk of cracking in joints and/in adjacent concrete is estimated by checking shear forces in joints and the ratio between the actual maximum principal stress ant the actual strength of the concrete. The shear force has been estimated both by simple methods as well as by two-dimensional calculations. The risk of cracking in the concrete and/or in the joints is estimated with the computer program ConStre. The restraint from a resilient foundation or rock on a young concrete construction is estimated by a simple method that is exemplified. It is shown that the restraint can be neglected in some cases.

Trikåkonstruktion med 3D-effekt för väggpaneler i lastbilar, ersättning av polyuretanskum

En vanligt förekommande laminering är polyuretanskum, som används för att ge egenskaper som mjukhet, komfort och flexibilitet till textiler. Ett användningsområde som tillverkaren och leverantören Borgstena Group Sweden AB använder polyuretan till är lastbilars väggpaneler. De vill dock ersätta den polyuretanskumlaminerade dubbeljerseytrikån som används idag med endast en ren trikåkonstruktion för att slippa problem som dellaminering och minskade töjegenskaper. Dessutom så har den kemiska sammansättningen av polyuretan som används i lamineringen visat sig vara belastande för både miljö och människor. I denna rapport klargörs varför polyuretanskum behöver ersättas och vilka möjligheter som finns i dagsläget för att göra detta.

Höga hus med deformerbara fundament på pålar : Pålkrafters avvikelse visavi klassisk teori samt förskjutningar beroende av vindlast

When forces in foundation piles are calculated according to classic theory, thefoundation are assumed to be infinitely rigid which means that the foundation will notbend. High buildings need their whole width to be stable and use the ground floorwall as a foundation. But when, for example windows are needed in the ground floorwall, the stiffness of the foundation decreases which change the forces in the piles. Inthis report the difference of pile forces versus classic theory has been analyzed, and ifpile forces can be calculated as in classic theory. Further on, the effects of the wallmovement were analysed and how the buildings crack safety would be affected by themovement at the ground floor.

Specialidrott eller inte? : Kan elever från riksidrottsgymnasiet i karate jämföra sig med svensk karate elit?

SammanfattningInledning: Specialidrott har funnits i skolvärlden sedan 70-talet och har lett till att många ungdomar har kunnat kombinera skola och elitidrottssatsning vid sidan om varandra. Det har skapats RIG (riksidrottsgymnasier) och ämnet specialidrott har lagts till som en kurs på gymnasieskolan. Målet med RIG var att göra det möjligt för talangfulla ungdomar att kombinera elitidrott med gymnasiestudier då gymnasietiden anses vara en brytpunkt för när elitsatsningen börjar. Att gå på ett RIG innebär även att få träna väldigt mycket och tävla med många av de bästa i samma åldersgrupper. RIG-systemet har producerat många svenska elitidrottare i olika idrotter.

SAMVERKAN STÅL/BETONG : Kontroll av kapacitet hos blockankare i Connector Samverkansbalk

In April 2007 we contacted Lennart Augustsson at Designpartners AB in Västerås. He came up with the idea to investigate and evaluate their construction of a interaction beam, CSB-beam. CSB is short for Connector Interaction beam. The beam is based on a horizontal C-profile of high-tensile steel and in the bottom of the profile are vertical flat bar welded so called block connectors. These block anchorsare also made of hightensilesteel.

Analys av instyrning och rolldynamik

When driving hard and cornering on a circuit good control of a car?s roll is desired, so the car reaches steady state quickly but yet in a controlled fashion. This control is mainly given by the combination of the cars springs, shock absorbers and anti-roll bars.The aim of this report is to investigate, analyze and measure a Porsche Boxster?s turn in behaviour and roll dynamics as well as with the aid of simulation results give suggestions for improvement of the previous mentioned combination.Two different simulations were made, one based on a simpler model that was based on an evolved version of the bicycle model in Matlab and one was more advanced model in the simulation software rFactor. Measurements of the real car was made using a GPS-based measurement system.

Testbänk för luftlager

Test bench for air bearingsThis thesis work consisted of bringing forward and defining the test parameters relevant for a test bench and constructing a test bench that can test and verify the largest existing air bearings that are of use in Micronic Laser Systems AB machines. Because the knowledge about air bearings is limited it is thought that with the help of the test bench the knowledge would increase and in that way improve the air bearings.After learning more about air bearings and their purpose at Micronic Laser Systems AB, I started the concept phase for the test bench. For each part in the test bench I consulted my two tutors, Torbjörn Hedevärn and Johan Bergqvist, at Micronic Laser Systems AB. The final concepts where documented as 3D-modells in Solidworks and some of them have been tested in Solidworks FEM-program.The test bench is designed so that, with the help of a pneumatic cylinder, 25 kilo weights are placed on the air bearing to test its stiffness, damping and the pressure performance under its surface area. To test these parameters the test bench has to have a pressure meter, accelerometer and a microcator.

Naturlig haptisk kraftåterkoppling från volymdata

As the volumes are entering the world of computer graphics the pure volume visualisation becomes a more important tool in for example research and medical applications. But the advance in haptics --- force feedback from the computer --- is behind. In volume haptics no equal to the proxy method so popular in surface haptics has yet emerged. Some implementations of volume haptics even use surfaces as intermediate representations so that surface haptics can be used.The intention of this work was to create natural feeling haptic feedback from volumetric density data using pure volume haptics. The haptic algorithm would be implemented in Reachin API for the Reachin Desktop Display, together with other parts to build up a usable volume visualisation environment.To achieve the feeling of stiffness and friction dependent on tissue type, a proxy based method was developed.

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