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24 Uppsatser om Bending - Sida 1 av 2
?dn?ris?: att b?ja st?nger till t?ltk?ta
This thesis is my exploration of the immaterial heritage that is the craft of Bending of ?dn?ris?
out of spruce. It?s a broken tradition that is scarcely described, mainly through Yngve Ryd?s
report T?ltk?tor (1999) that contains interviews with two knowledge keepers, Nilas Tuolja
and Johan Rassa. Yngve Ryd?s report went against the earlier opinion by the mid 20th century
ethnologist Ernst Manker who claimed that they were only made exclusively out of mountain
birch that has curved growth.
As a background, I discuss the special importance of heritage conservation, both material and
immaterial, in a S?mi context as being an indigenous people.
Dimensionering av bärverk av stål : En jämförelse mellan Eurokod och BKR
The design regulations of Boverket (BKR) have long been the mandatory standard for construction design in Sweden. However from the end of the year 2010, the BKR will be replaced by the European standard Eurocode (EC). The transition to EC has been delayed and it is not until the second of May 2011 that the use of EC will be mandatory. Because EC and BKR differ from each other it is highly interesting to investigate and explain these differences.The purpose of the thesis is to compare the two standards and investigate how they give different results or not for the dimensioning of structures of steel with associated loads. The current project HVC (Pets Science Center) in Uppsala is used as a model for the design of the steel structure used in this study.
Dimensionering av betongkonstruktioner : En jämförande studie av BBK 04 och Eurokod 2 vid dimensionering av balkar och pelare
Today, we use BKR and BBK 04 when designing concrete structures inSweden, which will, in the near future, be replaced by Eurocode 2. When you are designing buildings, you will use Eurocode 2 Part 1-1 and with this new standard, some new rules and general rules will be necessary to adopt. To examine how BKR and BBK 04 tells apart from Eurocode 2 when designing concrete structures, one beam and one column with often common dimensions, is studied. The beam is designed with consideration of (considerate to) durability at Bending moments, shear forces and control of cracking. The column is designed with consideration of durability at eccentric axial load and Bending moments in cross section on account of (due to) geometric imperfections. BBK 04 has gone one step closer to Eurocode 2 than earlier editions and the things that are different, when calculating reinforcement, is how they use the partial factors.
TV-stativ med nytt ställdon
The purpose of this thesis work is to evaluate how the physical behaviour of a pipe bend is affected by the pipe Bending procedure. Effects such as initial ovalization, thinning, thickening and plastic hardening from the Bending procedure are examined and the mechanical properties of pipe bends containing these effects are investigated.This has been evaluated by creating a detailed Finite Element model of a pipe that is being bent. Then the differences compared to a bent tube in a virgin state, so called Elbow elements and an analytical in-house program have been evaluated. The virgin state refers to a model of a pipe that is bent from the beginning, thus having a homogeneous thickness and not containing any plastic hardening. The Elbow element is a calculationally cheap element, specially developed for accurate calculations of pipe bends in an initially virgin state.The goal with the thesis work is to get a better picture of what happens to a pipe as it is being bent, how this affects the mechanical properties and to evaluate the possibility to develop an easy method for taking these effects into account when using the Elbow element.This report describes the layout of the work and how the detailed FE-model has been constructed.
Fiberföstärkning av Limträbalkar
Glulam is a product that was engineered to make use of timber in a more efficient way. Bychoosing timber of similar quality and discarding natural defects during production, thedevelopment of a stronger cross-section is achieved.Carbon fiber is a relatively new material with a high tension capacity. This feature is used toexamine how the Bending capacity of the beams improve by adhering carbon fiber laminateson the lower edge of the beamsThe strength of the material is tested with three experiments: carbon fiber on the bottom of thebeam (a), carbon fiber attached to the lower sides of the beam (b) and carbon fiber in thebeam, covered with a layer of wood (c)The results show that the first case, where the carbon fiber is attached to the bottom of thebeam, gave the best result with an increase in capacity of 59 % compared to the nonreinforcedcontrol. The other two cases also show an improvement in capacity, beam-type 3had a capacity increase of 47% and beam-type 4 increased with 25 %Tests were also made with glulam beams reinforced with fiberglass, but these tests were notanalyzed in depth because the purpose was to compare the capacity to carbon fiber. Thisbeam improved its capacity by 40.3%.The tests show that carbon fiber as a reinforcement material for glulam is a good choice whenthere is a requirement for stronger cross-sections in both new production and renovation ofold buildings.
Analysmetoder för rörsystem
The purpose of this thesis work is to evaluate how the physical behaviour of a pipe bend is affected by the pipe Bending procedure. Effects such as initial ovalization, thinning, thickening and plastic hardening from the Bending procedure are examined and the mechanical properties of pipe bends containing these effects are investigated.This has been evaluated by creating a detailed Finite Element model of a pipe that is being bent. Then the differences compared to a bent tube in a virgin state, so called Elbow elements and an analytical in-house program have been evaluated. The virgin state refers to a model of a pipe that is bent from the beginning, thus having a homogeneous thickness and not containing any plastic hardening. The Elbow element is a calculationally cheap element, specially developed for accurate calculations of pipe bends in an initially virgin state.The goal with the thesis work is to get a better picture of what happens to a pipe as it is being bent, how this affects the mechanical properties and to evaluate the possibility to develop an easy method for taking these effects into account when using the Elbow element.This report describes the layout of the work and how the detailed FE-model has been constructed.
Optimering av sintrade kugghjul
Powder Metal (PM) gears are machine element components which operate under the same principle as conventional gears, but, due to their intrinsic material characteristic need to be designed slightly different, and its manufacturing process offers advantages previously unobtainable by conventional steel gear manufacturing methods. The use of PM in similar applications, such as synchronous hubs, makes them a suitable candidate for production in such material. The current master thesis work focuses on gear design using PM by utilizing finite element method (FEM) to reduce weight and inertia taking into account root Bending strength and tooth deflection.First a topological optimization is used to determine feasible candidates for different web designs which have as objective to reduce volume, similar topologies were shown during different loading conditions; and hence, this topology was chosen as a suitable candidate. A shape optimization of the topological candidate was performed having as state variables root Bending strength, independent for compressive and tensile side of the tooth loading; and tooth deflection, which in concept can be correlated to static transmission error (TE).Another aspect in this thesis analysed is the possibility to incorporate non-trochoid root geometry, a trochoid root is always present when machining with a hob, into the gear root and hence reduce the stress concentration here. Due to the use of PM, a non-symmetric optimized root can be achieved and hence be optimizing compression and tension.Results showed significantly lower inertia, for example certain results showed 40% reduced when compared to solid gear, with adverse effects as increase in tooth deformation and increase in maximum principal stress.
Utvärdering av akupunktur som behandling vid ryggömhet hos häst : en pilotstudie
Acupuncture has been used for thousands of years in China. Written documents concerning veterinary acupuncture has been found dated around 650 B.C. Acupuncture has gained greater acceptance in the western world the last decades and many countries have established their own veterinary acupuncture organizations.
Many studies report good results after acupuncture treatment and back pain in horses is considered a good indication for acupuncture treatment. In studies published, the results are subjectively evaluated. To get a qualitative, scientific evaluation of acupuncture treatment, objective measurements, control groups and statistical analysis are needed.
This pilot study presents a case where acupuncture has been used for treatment in a horse that was diagnosed with back pain.
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.
INVOXICATED. En interaktiv lek med ljud
Invoxicated is an interactive play sculpture where children can explore the wonderful and playful opportunities of sound. Talk into one end of the sculpture, and the sound will travel through the sculpture and come out in the other end. On its way, the sound gets distorted by a number of sound effects. By Bending the sculpture?s body, and pressing the sculpture?s buttons, the sound effects gets altered in real time.
Standardisering av snöröjningsplan : Instruktioner, råd och tips för snöröjning av tak med stora spännvidder
The Swedish winters 2009/10 and 2010/11 were rich in snow and many roofs collapsed, mainly largespan frames. Investigations were made and the amount of snow was not the primary cause, insteadthere were several other causes. One of these was that in some cases roofs were shoveled in anunfavorable manner which affected the load patterns negatively, so causing the roofs to collapse.Most people lack the knowledge of how shoveling will affect the roof. Had there been an increasedunderstanding regarding shoveling, some roofs could have been prevented from collapsing.Through both qualitative and quantitative research in the form of interviews and calculations thetheoretically best ways to shovel a selection of roof types is presented in the report. The roofstructures covered are 3-compartment, continuous and Gerberspliced metal roof decks.
Skiktlimning i skolslöjden : ett gestaltande examensarbete om skiktlimning i slöjdundervisningen
Syftet med detta gestaltande arbete är att ta reda på hur skiktlimning fungerar i skolundervisningen och vilka möjligheter som finns för att integrera den mer i skolan. Syftet är också att bidra med kunskap om tekniken till andra lärare. Detta är ett gestaltande examensarbete. Tre olika produkter tillverkades med hjälp av skiktlimning. Processen dokumenterades så att lärare och elever ska kunna använda dem i slöjdundervisningen.
Spänningsanalys av axel-länkmekanism på borr-rigg
This master thesis is intended to give an increased understanding of the stress state in an axle, which is assembled in one of Atlas Copco?s mountain drilling rigs. The main problems investigated were how the axle is affected when the bearing is worn, when the pretension is varied, and how to dimension the axle. Answers to these questions were found by using hand calculations, practical testing and with Finite Element analyzes. The dimensioning of the axle is currently based on the Bending stress, but the author?s opinion is that the axle should be dimensioned considering the equivalent stress.
Skadliga nollflödespunkter i Fortum Värmes fjärrvärmenät i Stockholm : En analys av dess förekomst och effekter
When several production units provide a district heating network, water is pumped from different directions. When the flows from the plants finally meet in the network, the water can be completely still. These places are called zero flow zones. In district heating networks with several plants, which also have different supply temperatures, large and frequent temperature fluctuations can occur when the zero flow zones move. This may cause wear on the pipes, a phenomenon called low cycle fatigue.For this reason it is important to examine where and when zero flow zones that cause temperature changes occur.
Utveckling av Trailplate - En skyddande innersula
The project aimed to develop a protective and stabilizing insole called Trailplate for soft andlight shoes. The demand came primarily from off-road runners in France, Switzerland, andAustria. The project was carried out at Icebug, a company that develops shoes mainly forrough terrain. The main focus has been on the trailplate which is designed to fit severaldifferent shoes.Torsional stiffness and Bending resistance were the main objectives. To improve the existinginsole, a material with the right features was required.