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1566 Uppsatser om Dam safety uplift concrete dams buttress dams horizontal joints - Sida 32 av 105

Observatörer för skattning av verktygspositionen hos en industrirobot : Design, simulering och experimentell verifiering

This thesis approaches the problem of estimating the arm angles of an industrial robot with flexibilities in joints and links. Due to cost-cutting efforts in the industrial robots industry, weaker components and more cost-effective structures have been introduced which in turn has led to problems with flexibilities, nonlinearities and friction. In order to handle these challenging dynamic problems and achieve high accuracy this study introduces state observers to estimate the tool position.The observers use measurements of the motor angles and an accelerometer and the different evaluated observers are based on an Extended Kalman Filter and a deterministic variant. They have been evaluated in experiments on an industrial robot with two degrees of freedom. The experimental verification shows that the state estimates can be highly accurate for medium frequency motions, ranging from 3-30Hz.

Sa?kerhet och integritet i webbapplikationer : En orientering o?ver sa?ker utveckling

The use of Web applications is a growing area. While the possibilities and functionalities are increasing, so is the complexity of them, together with the threats against them because the complexity also opens up the application to vulnerabilities. It is therefore important for developers to know how a web application can be developed with security in mind.This study?s intention has been to create an introductory documentation of what kind of techniques that exists which can produce higher security, which methods there can be within the development process and what to think about when programming secure web applications. In this paper we have investigated how theoretical manuals in the IT security department handles that area, and interviewed two developers from two different companies to see how they use security in their web applications.The study has an exploratory technical perspective and does not explain how to practically use and interconnecting different security-enhancing technologies, but is more suppose to give a first glance at what is available and sow a seed for those interested to continue reading further about the subject.

Isolerande balkonginfästningar : Thermally-insulated balconies

In this work a study has been performed to show the different kinds of insulated balcony connections exists on the market. In the work there is also a short description of thermal bridges concerning balconies. A description of older solutions for balcony connections is given as well as a calculation of the difference in energy costs for a insulated balcony connection compared to the standard connection. The work includes a short description of the different products. After that there is a short information about their insulation properties, durability, acoustic performance, assembly, computer programme and a short analyses for each product..

Vad har egentligen säkerhetskulturen för betydelse? : En flerfallsstudie på åkeriföretag

Från det välkända begreppet företagskultur har ett nytt begrepp vuxit fram, Säkerhetskultur. Detta kan ses som en förlängning på det tidigare begreppet där säkerheten ställs i rampljuset. Det sägs att åkeribranschen som helhet har en dålig säkerhetskultur samtidigt som ett bristfälligt säkerhetsbeteende är ett tecken på en högre skaderisk för företagen. Men vad har egentligen säkerhetskulturen för betydelse?Syftet med uppsatsen är att förklara hur säkerhetskulturen ser ut i åkeriföretag.För att kunna besvara syftet med uppsatsen har en kvalitativ flerfallsstudie genomförts, där de sex åkeriföretagen A till F har undersökts.

Åtkomststudie för robotiserad svetsning av flygmotordetalj

The aim of this thesis was to investigate if the robotized welding method FSW (Friction Stir Welding) could be applied for joining a rotating structure in an aero engine at Volvo Aero Corporation. FSW is expected to introduce less defects than today?s welding methods and could therefore be suitable for critical aero components. The material is the nickel based alloy Inconel 718, however a material experimentation is outside the scope of this report.The main goal of this study is to verify if the ESAB ROSIO robot based FSW-system has a suitable work space to be able to weld the rotating structure, and if the welding tool has accessibility to the joints. The FSW-process needs a rigid fixture, and a number of fix-ture concepts are presented based on a proposed weld sequence.

Anstaltens ambivalenta funktion : En studie av den samtida kriminalvårdsdiskursen

Due to the attention of several escapes, rescue attempts and hostage situations from Swedish prisons during the year of 2004 a debate about correctional system and safety arose. It resulted in official reports and proposals to improve the safety of the institutions. The incidents of 2004 will most likely have an effect on the discourse of the correctional system. The purpose with this study is to analyse which discourses that today can be distinguished in the correctional system and thereby will be the foundation of the correctional systemof tomorrow. The method used to answer the purpose of the study is a Foucauldian based discourse analysis.

Förbättring av väggfäste för flatscreens

The project was carried out in cooperation with the department of product development IOS at IKEA. The work included improvements of a new existing product that Ikea soon will release on the market, Observatör, a wall bracket for flat screens. The product is supposed to fulfil the needs within this market for IKEA. However, since Ikea was not satisfied with it, our work was to carry out the improvements that were specified in the beginning of the project. Another task in the project was to develop a side-product that is supposed to be used together with Obeservatör for storage of DVD/decoders.The project included labour as problem definition to final technical drawings and a prototype.

Lyftanordning för kraftuttag

This thesis has been developed inassociation with Strängbetong AB, Sweden.A few years backCementa AB introduced a new type of cement on the Swedish market: Byggcement,which is a Portland Limestone Cement. This type of cement is better for theenvironment and cheaper than Rapid Hardening Cement which is used today at SträngbetongAB.Strängbetong AB isvery interested in a change of cement in the factory and wants to know what ittakes to make a transition from Rapid Hardening Cement to Byggcement.This final projectaims at investigating how the workability and strength development are affectedby a transition from the existing cement to Byggcement and how we can change theproperties of the concrete by adding different types of superplasticizers. Laboratory and factoryexperiments were made, to investigate the transition..

Dimensionering av betongplatta på lös undergrund. En jämförelse mellan tre beräkningsprogram

Today more effective computer programs are in use, regarding design of geotechnicalconstructions. There is a risk that the theoretical background of the computerprograms, its limitations and the signification of the choice of soil parameter isforgotten when the computer programs become more user-friendly.This Master thesis deals with simulation and analysis regarding three computerprograms, FEM-design, with the addition Raft, Plaxis and BE-slab. Comparisons aremade for settlement and maximum moment in a concrete-plate. FEM-design is a threedimensional FEM-program, foremost created for design engineers. Plaxis is a twodimensional FEM-program, intended for geotechnical engineers while BE-Slab is aBoundary elements program in two dimensions that is mainly used by designengineers.

Betongåtervinning En fallstudie av rivningsobjekt i betong

I takt med att besökare och patienter ökar måste kontinuerligt Östra sjukhuset verksamhet utvecklas. Detta medför omläggningar i trafiken och förflyttningar av verksamheter. Idag finns flertalet brister kring Östra sjukhusets fysiska planering som behöver ses över, dessa är bland annat trafikflöden, säkerhetsaspekter och parkeringsmöjligheter.Rapporten redogör för förändringar i den fysiska planeringen som förbättrar dess utformning. Genom studier av relevant litteratur och diskussioner med expertis har förslag av problemområden tagits fram. Dessa har sedan bedömts efter listor av deras respektive för- och nackdelar som kunnat urskiljas.Arbetet visar framtagandet av ett väl fungerande förslag som kan verka som en bas för idéer till nutida och framtida förändringar kring den fysiska planeringen.

De talar av erfarenhet : uppfattningar om begreppen demokrati och diktatur hos vuxenelever med utländsk bakgrund

I have in this study examined, through qualitative interviews, how adults with foreign background that are pupils in adult education in Sweden, understand the concepts democracy and dictatorship. Their expressed understandings have been compared with their former life experiences as well as with the aim of the social studies to create a qualitative understanding of essential social concepts. My starting point is theories about the adult in leaning processes. It has been assumed that the adult interprets the world much through former life experiences. I have also relied on the idea that having a qualitative, more scientific, understanding of essential subjects is important for the adult as a member of society and participator in the on-going political debate.

Tidsstudier i kalvuppfödning :

Swedish agriculture stands in front of big changes the whole time. As a milking producer you have to adapt and develop the company to these changes and find the best solution. This potential is easy to find if you compare your company with other similar companies. Labour cost is the biggest cost in milking production after the cost for food. Today it is rather easy to measure how many hours per cow different system of cow houses needs, but we do not know so much about how many hours it takes to breed a calf. To learn more about the labour time with the calves during the first time after the calf was born, I made time studies on five different farms with calf hutches, automatic milk system, large calf boxes, and smaller calf boxes with teat buckets.

En intuitiv & lättillgänglig flyktmask för gruvmiljö

I have always lived around mines and around people work­ing with mines. They are a natural part of my life and, inev­itably, a great interest of mine. When time came to make a decision for a degree project, focusing on the mine context felt as natural as breathing.In LKABs underground mines, safety in fire accidents is a great priority. Of outmost importance for the escape is to have a personal gas filter for filtration of smoke and/or gas. My design project resulted in a concept which is aimed at shortening the user journey from the start of the accident until the user has applied the personal safety solution and is ready to escape.Throughout the project I?ve been working with a context which is heavily regulated, and all problems are serious, important ones.

Tollarsjuka hos hund : en retrospektiv studie med journalsammanställning av 18 hundar

?Tollarsjuka? is a disease with a suspected immunopathological background seen in Nova Scotia duck tolling retrievers. Pyrexia, lameness, stiffness and joint- or musclepain are typical clinical signs. The purpose of this study is to describe case histories from dogs with a possible evidence of ?tollarsjuka?. 18 private dogs were included in this report. Generalised stiffness, lameness and fatigue were the most frequent manifestations of the disease.

Trafikklasser för markplattor av natursten : förslag till klassificeringstabell

This report deals with hard surfaces and the factors which are behind the criteria for dimensioning, also dependent on the level, or volume, of traffic. A test was made on slabs of two kinds of natural stone. This was made to see if the values that were reached for breakload was transferable to the same tables that the concrete industry is using for surface dimensions of slabs and paving stones. The test showed very high values and the result, together with the written study, led to the author?s suggestion for a classification table where slabs of natural stone were divided in to different classes depending on traffic, thickness and durability..

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