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107 Uppsatser om Creep coefficient - Sida 4 av 8

Nedbrytning av vägar: Jämförelse mellan axlar med singel- respektive tvillingmontage

When designing roads it?s important to knowwhat loads will bedriven on it. The axles on heavy vehicles can either have super single tires ordual tires which, according to studies, damage the roads differently. The SwedishTransport Administration is developing an understanding for the character ofthese different kinds of axle and tire types on the loads induced on Swedishroads. In this thesis a field study was conducted to determine the distributionbetween axles with super single tires and axles with dual tires on heavy vehicles.A highway, a country road and a national road were investigated during thestudy.

Spillvärmeåtervinning

SAPA´s resource of waste heat is the basis for this thesis to investigate the possibility of energy assets in their cooling water and possible uses for it. The energy in the waste water is greater than the current need which has three uses which are (1) heating the factory, (2) converting liquid propane to propane gas and (3) local domestic heating. The average energy load that is available is 1, 7 MW and the average temperature in the cooling water is 41°C. The total energy load at dimensioning out side temperature is approximately 1,6 MW for the three current uses. The temperature is currently too low to be used directly in the existing systems so an upgrade is needed.

Rätt fönster i olika väderstreck : En undersökning av energieffektiva fönsters påverkan på byggnaders energiprestanda

The Swedish building stock accounts for nearly 40 percent of the total energyconsumption in the country. Properties built today are likely to last for 100 years orlonger. This places high demands on long-term and smart energy solutions that willkeep the future Swedish building stock energy consumption at low levels. This thesishas focused on examining how the energy performance of buildings is affected bydifferent choices of window types in different cardinal directions. The objective wasto obtain a basis for recommendations on how window properties can be optimizedfor different types of buildings and orientations.

Samband mellan laserdata och fältdata

To make it easier for forestry planning the forest owners needs data which describe characteristics of the forest. Such data you usually get from some type of inventory. A relatively new technology which probably is getting more important in the future, is laser scanning because of lower costs. But because the laser technology is relatively new you need to compare it with conventional inventory technologies to get better understanding of the possibilities the laser technology gives. This work intends to estimate field measured characteristics of the forest from laser data with help of regression analysis and then see which of the field measured properties that best could be estimated and which laser variables that gave the best results. This study shows that heights has the best estimates, but biomass, diameter and volume also gives good estimates.

Formulering och provning av en ny typ av sågkedjeolja

Formulation and testing of a new type of chainsaw lubricantThe company Agro Oil has come up with the idea of developing an environmentally adapted chainsaw lubricant with a new unusual base fluid. A field test with a tree-harvester shows unsatisfactory low temperature properties and high wear. In this work the viscosity, price and pour point of different combinations of the given base fluid and three other base fluids have been investigated. Desired viscosity and price are determined for different formulations. The new lubricants tested show lower pour points than almost all products on the Swedish market.A test equipment has been developed to investigate the wear.

Microstrip Solutions for Innovative Microwave Feed Systems

This report is introduced with a presentation of fundamental electromagnetic theories, which have helped a lot in the achievement of methods for calculation and design of microstrip transmission lines and circulators. The used software for the work is also based on these theories. General considerations when designing microstrip solutions, such as different types of transmission lines and circulators, are then presented. Especially the design steps for microstrip lines, which have been used in this project, are described. Discontinuities, like bends of microstrip lines, are treated and simulated.

Varför svänger stenen? : En studie i curlingens komplexa tribosystem

The tribo system ice-curling stone was investigated in order to understand the mechanisms behind the stones' behavior on the ice sheet. The problem with non-identical stones should also be addressed.The stone curls, that is, its sliding path deviates from a straight line to the right for a clock-wise rotation and to the left for a anti-clock-wise rotation. Several mechanisms to explain this behavior have been proposed over the years but none has been successful.By carrying out experiments at the local curling rink and studying silicon castings of ice- and stone-surfaces with scanning electron microscopy and vertical scanning interferometry, it has been decided that the curl is not due to dry friction, ice-debris or the difference in friction on the left and right side of the stone. The side force comes from the fact that the friction is higher at the back of the stone than at the front.The contact between stone and ice is never completely dry, nor in the hydrodynamic lubrication regime. It is probably a combination of hydrodynamic lubrication and a contribution from mechanical scratching of the ice.

Effektivisering av urvalsprocesser vid analysering av björnspillning : Ett förslag till den svenska förvaltningen av brunbjörn Ursus arctos

The aim with this report is to formulate a strategic method to optimize selection processes of DNA-samples from a faeces inventory to identify as many individuals in as few analyzes as possible, and by that keep down the costs of brown bear management. Brown bear management in Sweden founds today on results from faeces inventory and is substantially led by the county administration boards. Data from the years of 2004 and 2009´s inventories in Västerbotten was used to test and evaluate different methods in selection processes of which faeces that should be sampled. Comparison were made between making selection by chance, by spatial distribution and by calculating variations in logistic regressions coefficient b, in other words bear density and probability in finding same individual in several faeces. We can show making selection by chance is the most uncertain method.

Spelutveckling och lansering av applikation till Android

For several years Uppsala University together with several companies has been involved in a WISENET project aimed at improving railway transport security. By placing a sensor system near the wheels of each wagon, the temperature of the bearings can be measured and transmitted to a collector placed centrally on the wagon. This in turn transmits the collected data to RFID receivers placed intermittently along the railway.As the signals are transmitted wirelessly, problems may occur as the antennas get dirty or coated with ice and snow. To determine the effects of these coatings, several tests were performed examining the reflection coefficient S11, the impedance Z11 and the efficiency eta of an antenna, and how they varied when various coatings were placed over the antenna. Examined coatings were ice, snow and water to determine the effects of weather, and various metal-based coatings: powdered iron both pure and partially oxidized, and iron ore granules.

Fönsterutredning för radhusområdet Skeppsvägen

Mitt examensarbete innefattar en fönsterutredning för radhusområdet Skeppsvägen i Bålsta. Fastighetsägare är Håbohus AB och examensarbetet har skrivits för Skanska Sverige AB. Arbetet har skrivits på plats i Bålsta där Skanska Direkt AB har eget kontor och erhåller idag totalentreprenaden för renovering av Skeppsvägen. Arbetets syfte är att klart och tydligt redovisa eventuell effekt och energibesparing vid byte av befintliga fönster och altandörrar.Undersökning av fönster och altandörrar har gjorts okulärt, med värmekamera och med fuktkvotsmätare. Vid den okulära besiktningen noterades färgsläpp på fönster.

Termoelektrisk lagring i system med fjärrvärmeproduktion

With increased deployment ofintermittent renewable energy, such aswind and solar power, energy storagebecomes necessary to help reduceproduction peaks. Thermoelectric EnergyStorage is a method still in researchphase, which stores electricity in hotwater at a temperature of 120 ° C. Thisthesis aims to examine whether theThermoelectric Energy Storage would bepossible to integrate into existingpower generation such as a combined heatand power plant, and how the technologypotentially could function in theelectricity market. ThermoelectricEnergy Storage consists of a chargingprocess and a discharging process, bothoperating by the working fluid CO2. Toincrease the efficiency of theThermoelectric Energy Storage, wasteheat from the district heating networkis integrated.A model of the Thermoelectric EnergyStorage has been developed and it wascalculated by thermodynamic propertiesof the working fluid, CO2, in thevarious process steps.

Experimentell konstruktion av pickupsystem anpassat för trummor med hjälp av MATLAB

For several years Uppsala University together with several companies has been involved in a WISENET project aimed at improving railway transport security. By placing a sensor system near the wheels of each wagon, the temperature of the bearings can be measured and transmitted to a collector placed centrally on the wagon. This in turn transmits the collected data to RFID receivers placed intermittently along the railway.As the signals are transmitted wirelessly, problems may occur as the antennas get dirty or coated with ice and snow. To determine the effects of these coatings, several tests were performed examining the reflection coefficient S11, the impedance Z11 and the efficiency eta of an antenna, and how they varied when various coatings were placed over the antenna. Examined coatings were ice, snow and water to determine the effects of weather, and various metal-based coatings: powdered iron both pure and partially oxidized, and iron ore granules.

Äldre personers attityd till styrketräning: utformning och reliabilitetstestning av en provenkät

Syftet med denna studie var att utforma och reliabilitetspröva enkätfrågor om äldre personers attityd till styrketräning. En enkät bestående av 47 frågor och påståenden delades ut till 31 äldre (60-81 år) personer som fick besvara enkäten vid två separata tillfällen. Varje enskild fråga analyserades för test-retestreliabilitet på tre olika sätt: 1/ Intraclass correlation coefficient (ICC) 2/ Absolut reliabilitet med 80% respektive 95% konfidensnivå samt 3/ Proportion of agreement (PA) med PA% och PA ±1%. Enligt gränsvärden som sattes för acceptabel reliabilitet hade 16 frågor ett värde på ICC <0,50, 11 frågor ett pa(%) <60%, 16 frågor ett värde &lt;80% på pa ±1%, nio frågor en absolut reliabilitet av =>2,0 vid 95% säkerhet och 12 frågor en absolut reliabilitet =>1,5 vid 80% säkerhet. Dessutom visade analysen av absolut reliabilitet att det för 2/3 av frågorna krävs två skalsteg för att påvisa en skillnad vid 95% säkerhet.

Hållbarhetsredovisning : En studie av Vattenfall AB i ljuset av GRI

This essay is about democracy and how a democracy index can be used as a tool to illustratethe gap between reality and ideal. The purpose of this study can be expressed by two researchquestions: Does the Economist Intelligence Unit's (EIU) democracy index illustrate thedistance between reality and the ideal of democracy presented by Dahl? and Can the EIU'sdemocracy index be modified by a) internal adjustments and b) using the variables includedin World Economic Forum?s (WEF) equality index?By using a combination of theories (Dahl?s theory of democracy, Rawls theory of justice andchosen theories critical to liberal democracy) as an analytical framework the following twoquestions have been answered:1) Which of the variables included in the EIU's democracy index have the potential to capturethe level of political equality?2) Which of the variables included in the WEF?s equality index have the potential to capturethe degree of political equality?By using a quantitative method the study?s third and last question has been answered:3) How strong is the rank correlation between the EIU?s democracy index and the WEF?sequality index, that is; how strong is the rank correlation coefficient (rho)?The data presented by the WEF?s equality index indicate that women are systematicallydiscriminated against as a group. From a democratic perspective the EIU may need tomeasure inequalities at a group level in order to capture the lack of political equality betweenindividuals. By reformulating some of the EIU?s variables, by revising the EIU?s point systemand by using the variables included in the WEF's equality index to extend EIU?s democracyindex, the chances of capturing the gap between reality and the ideal of democracy presentedby Dahl would likely increase..

Konstruktion av formkropp pa JAS 39 E/F Gripen

The aim of this work is to develop new conceptual designs for the fairings that are situated between the fin and the rear fuselage on the new version of the JAS 39 Gripen aircraft, called the Gripen E/F. The designs presented should show a profit in the form of lower weight. To achieve weight loss, the possibilities of using other construction materials other than those which are available at Saab today were studied. Therefore, a material survey was carried out in which the market for modern construction materials was studied to get an idea of today?s level of technology.

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