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19 Uppsatser om Roughness sublayer - Sida 1 av 2

Strömningen i och över en skog : utvärdering av en 'mixing-layer' hypotes

A new theory for predicting the windprofile over a canopy has been evaluated. The theory was first presented by Harman and Finnigan (2007). The theory relies on the forming of a mixing-layer above the canopy, due to different mean wind in and above the canopy. Characteristics from both mixing-layer and Monin Obukhov similarity theory have been used to develop the governingequations that give the wind profile. The theory has been used to calculate wind profiles for sixdifferent atmospheric stabilities.

Vidhäftning mellan prefabelement och pågjutningsbetong : Undersökning hur skrovligheten påverkar vidhäftningskapaciteten vid skjuvning

Self-compacting concrete has soon been around for a decade. Recently the prefabrication industry has started to use this fairly new concrete type in larger scales, mainly because of its distinctive properties.  There are still certain areas that need to be thoroughly examined, such as bond capacity. There have been very few studies regarding shear capacity due to the fact that the procedure is complicated.This report will highlight a method to examine the shear capacity of different surfaces that have been prewetted as well as non-prewetted surfaces. The surface areas follow BBK 04?s and Eurocode 2?s demand for surface roughness.  A smooth surface will be completed in order to confirm if the different shapes influence the bond strength by shear stress or not.                       The purpose of this essay is to measure the bond strength within the shear capacity as well as examine the impact it has on surface roughness and treatment for shear bond.The method used to identify the shear capacity is called L-shaped Push-Off Test.

Glidytor och ytjämnhet med avseende på friktion och tätning

Gliding and sealing functions in Öhlins shock absorbing systems sets great demands onthe contacting surfaces. In this particular case, the bushings and the sealings on acylinder piston. The surface wanted is a surface with both low frictional forces and smallleakage. This study was done with the goals of investigating and determining existingsurfaces due to the frictional force and leakage. How can we in an easy mannerdescribe these?A number of ten front forks were part of a main study.

Perceptuell och akustisk bedo?mning av ro?stfunktion hos barn med tonsillhypertrofi : Effekter av kirurgi

In Sweden over 10.000 patients annually, mostly children, undergo tonsillar surgery. The most common surgical method is total removal of the tonsil, tonsillectomy (TE). During the last decade partial tonsil resection, tonsillotomy (TT), has been reintroduced and is associated with lower primary morbidity and less postoperative pain. The aim of the present study was to evaluate if and to what extent 4-5 year old children?s voice function are affected by tonsillar hypertrophy compared to controls and to study the effects of the two surgical techniques on vocal function.

Dragbrotschning av invändiga profiler

High-precision cutting in metal is very complicated, a lot of parameters affect the result: what geometries to be manufactured, surface roughness and tolerances to be achieved, batch size etcetera. When pull-broaching internal parts this might be even more important, than in any other cutting operation. Everything is machined in one single stroke and the general technology is built in to the tool, therefore big investments must be made to change the process. Milling for an example: one piece at a time is machined away, and a lot of parameters can be changed easily.It is very high pressure on the cutting-edge when the broach is cutting. To achieve the specified product and to avoid unnecessary toolwear it is essential to use the right cuttingfluid and the right cuttingspeed for an example.

Med andra bilder inga ord. En illustrerad berättelse.

This project has been about illustration, text and format with illustration as the main communication path.A study has been made of how these three elements interact, particularly how text and format affect the illustrations. The goal has been to create an illustrated story in a form of a book. The story is about the feeling of being alienated from other people and invites the reader to make their own interpretations. The main target audience has been the ones who is interested in illustration and storytelling, no matter of age.Colors has been inspired from animated movies and the natur. Various textures such as wood, fabric and metal for example has been scanned to create a rough feeling.

Computer Modelling of the Influence of Surface Topography on Water Repellency and a Study on Hydrophobic Paper Surfaces with Partly Controlled Roughness

A computer model based on minimization of the free energy, capable to predict contact angles and spreading transitions between Wenzel and Cassie mode for drops placed on surfaces with different topography were implemented in matlab. Simulations were compared with experiments documented in the literature. These showed that reported transitions between Cassie and Wenzel mode can be explained by minimization of the free energy. In this report, a study on the possibility of constructing water repellent paper surfaces with a combination of treatment with octadecyltrichlorosilane and topography changes, is included..

Virtuella vävnadsobjekt för medicinska träningsapplikationer

This Master thesis discusses the development of a virtual human soft tissue object for use in exercise applications of various medical procedures.The soft tissue object to be developed shall look like, feel like and behave as living human tissue. It shall give the user a realistic feeling of weight, softness and roughness, and shall behave in a correct way for exercise purposes. The soft tissue model is to be used in a three dimensional stereo graphic environment with haptic feedback. A prototype for practicing the procedure of inserting a catheter is built. The prototype is used to evaluate the potential of the virtual environment for medical exercise applications, and to assess the realism and usability of the soft tissue object.

Granskning av kvalitetssäkringsarbetet vid en ICC-profilbaserad trycksaksproduktion

To make your company change from a conventional workflow to an ICC-based workflow you need tomake investments in time and money. On the other hand you get your reward in terms of a stable andquality safe production. To choose this way of adjusting your company to new routines requires accuracyas well as a great deal of commitment. It is not only about having the right equipment. There area lot of factors that affect the quality of production.Our ambition with this report is to bring out the importance of general thinking when it comes toICC-profiling and to discuss on which basis printing profiles should be created.

GNSS-Styrning : Information för platschefer

An investigation of the heat impact of laser cutting on the material properties when producing tensile and impact test specimens of different steel types of varying thickness has been performed. The purpose of the thesis project was to provide recommendations regarding how much material that needs to be milled from the laser cut edge before tensile and impact tests. The study has been performed partly by investigating the test specimens by heat camera when the specimens were cut in the laser cutting line and partly by performing hardness tests, investigation by microscopy, and tolerance and roughness measurements and tensile tests of the laser cut material and material produced in the traditional multi operation machine. The results show that the heat affected zone in the thicker materials is greater than previously thought of, and that the currently used recommendation has to be adjusted. The study clearly shows that the thicker the material, the greater the heat affected zone, independently of the steel type, since the thicker material takes longer time to cut.

Utredning av laserskärningens materialpåverkan inför drag- och slagprovning : Teknisk Fysik med Materialvetenskap

An investigation of the heat impact of laser cutting on the material properties when producing tensile and impact test specimens of different steel types of varying thickness has been performed. The purpose of the thesis project was to provide recommendations regarding how much material that needs to be milled from the laser cut edge before tensile and impact tests. The study has been performed partly by investigating the test specimens by heat camera when the specimens were cut in the laser cutting line and partly by performing hardness tests, investigation by microscopy, and tolerance and roughness measurements and tensile tests of the laser cut material and material produced in the traditional multi operation machine. The results show that the heat affected zone in the thicker materials is greater than previously thought of, and that the currently used recommendation has to be adjusted. The study clearly shows that the thicker the material, the greater the heat affected zone, independently of the steel type, since the thicker material takes longer time to cut.

Funktionsentreprenad för beläggning och vägmarkering

This report is written in cooperation with the Swedish National Road Administration South-Eastern Region in Jönköping. The report is a result of the evaluation to give an answer to the question about how well the function contract has been carried out on the E4 in Östergötlands and Jönköpings län. The evaluation is divided in two hard parameters and one soft.The Swedish National Road Administration is interested in knowing how the standard on the road have been changed during the functions period, which is the reason why the first hard parameter is considering road standard. To evaluate the standard there have been a comparison of values from measures taken every year on the current road stretch. The second hard parameter considers economy.

Utvärdering av kirurgisk behandling vid organiska stämbandsförändringar hos barn

In Sweden surgical treatment of vocal fold lesions in children is fairly uncommon. At Falun hospital they have adapted a more generous attitude towards phonosurgery of children?s vocal folds. The purpose of the present study was to evaluate surgical treatment of organic vocal fold lesions in children and to assess the phonosurgical patient utility. The study was carried out at the Ear-, Nose- and Throat clinic, Falun hospital, Sweden.

Skrovlighet, hårdhet och ålder : Hur förhåller sig dessa till varandra i kalla förhållanden i Mellansverige

Idag lever 65 % av världens befolkning i länder där övervikt och fetma dödar fler människor än vad undervikt gör. I Sverige har fetman fördubblats sedan 1980 och idag lider ungefär varannan man och var tredje kvinna av övervikt eller fetma. Svenska studier visar även att ungefär vart femte barn är överviktigt och ett barn av tjugofem lider av fetma. Dagligen kan vi läsa i tidningar och se på tv hur människor kan göra för att gå ner i vikt, även hälsokampanjer och diverse hälsoupplysningar blir allt vanligare. Dock verkar inte detta tillräckligt för att hjälpa människor till en lyckad och långvarig livsstilsförändring.

Kemin bakom framtidens avgasrening : En studie av ureasönderfall under kvävgasatmosfär

The purpose of this work was to provide a better understanding of urea?s decomposition and byproduct formation in an SCR system on heavy trucks. In my experimental setup with TGA-DSC-FTIR (a combination of two thermal analysis methods and a method for gas phase detection), an FTIR method for urea in the gas phase was developed for the qualitative and quantitative determination of urea and its decomposition products. Chemicals such as urea, biuret, cyanuric acid and melamine of p.a. quality were used in this method development. Beforehand, there was no FTIR method available to detect these substances; hence, the aim of this work was to develop an FTIR method to understand the degradation chain of urea. The combination of TGA and DSC was used for analysis of different samples, where urea, biuret, cyanuric acid and melamine in varying amounts have been weighted in for various experiments in order to study the temperature at which a phase transition or reaction occurs, i.e.

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