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96 Uppsatser om Uncertainties - Sida 1 av 7
Robotstyrning med metoden Sliding Mode Control
The task in this thesis is the steering of one of Saab Bofors Dynamics robots using Sliding Mode Control, a method they never used before. The robot constitutes a system which in addition to perturbations and Uncertainties due to modeling imprecision, hold the difficulty of being highly time variant. In order to be able to keep required performance with Uncertainties and modeling imprecision present, the use of robust control methods like Sliding Mode Control is necessary. SMC is based on the states of the system being forced to stay on or in the direct vicinity of a hyper plane in the state space which is chosen in a way that gives the system dynamics desired properties. Other advantages with sliding mode are reduced order dynamics on the switching surface and total insensitivity to some Uncertainties and perturbations.
Risk och osäkerhet vid inträde på den svenska apoteksmarknaden: En studie om nya aktörer på en marknad under omreglering
The Swedish pharmacy market will be re-regulated in July 2009 which will present private actors with an opportunity to enter the market. Several risks and Uncertainties are associated with such an entry. The purpose of this thesis is to increase the understanding of identification and management of risks and Uncertainties associated with entering the Swedish pharmacy market. We also intend to investigate similarities and differences in risk identification and risk management as well as create an understanding of the underlying reasons for these similarities and differences. Three companies interested in entering the market have been interviewed and the interviews were conducted with an open approach to avoid influencing the companies? answers.
Kvantifiering av osäkerheter i lyftkraftsmodellen
With today´s power uprates in BWR reactors the bundle lift force has become aproblem. The lift force is calculated using a best estimate approach and the resultfrom the calculation should pass the existing lift force margin. Lift force margin isdefined so that the lift force may not exceed 80 % of the fuel weight. The margin issupposed to cover all the Uncertainties that exist in the lift force calculations.However, no uncertainty analysis has been conducted to quantify the Uncertainties.In this report the Uncertainties in the lift force model have been quantified. Each inputparameter to the lift force model which has been assumed to have an uncertainty isassigned a probability distribution.
Systematiskt arbete för att hantera osäkerheter vid mätning : vid Q-Med AB i Uppsala
This report is about helping Q-Med AB in Uppsala to start its implementation of uncertainty of measurements analyses in their manufacturing department. Prior to this, the company relied solely on personal experience or did not take this uncertainty into consideration at all during different kind of measurements, which means that some of the processes that the company previously believed were within specified acceptance limits, will actually fail when considering these sources of Uncertainties.Q-Med AB needed some sort of instruction to help the company, in a systematic way, to investigate different types of disorders that are affecting all kinds of measurements. This instruction includes a short summary about measurements and uncertainty of measurements in general and a detailed procedure about how these Uncertainties are going to be handled in their daily work.The goal was to be able to use this instruction to systematically locate, eliminate (when possible) and analyze all kinds of disorders when measuring. Q-Med is using a lot of different types of instruments when measuring different types of quantities, including temperature, mass, pressure and density. This instruction will hereafter be used for every instrument, regardless of quantity and type of instrument.The instruction is tested through 4 different kinds of measurements, for mass, temperature and humidity.
Elektronisk Handel : Framtagning av två implementeringsmodeller
This report is about helping Q-Med AB in Uppsala to start its implementation of uncertainty of measurements analyses in their manufacturing department. Prior to this, the company relied solely on personal experience or did not take this uncertainty into consideration at all during different kind of measurements, which means that some of the processes that the company previously believed were within specified acceptance limits, will actually fail when considering these sources of Uncertainties.Q-Med AB needed some sort of instruction to help the company, in a systematic way, to investigate different types of disorders that are affecting all kinds of measurements. This instruction includes a short summary about measurements and uncertainty of measurements in general and a detailed procedure about how these Uncertainties are going to be handled in their daily work.The goal was to be able to use this instruction to systematically locate, eliminate (when possible) and analyze all kinds of disorders when measuring. Q-Med is using a lot of different types of instruments when measuring different types of quantities, including temperature, mass, pressure and density. This instruction will hereafter be used for every instrument, regardless of quantity and type of instrument.The instruction is tested through 4 different kinds of measurements, for mass, temperature and humidity.
Del projekt inom ClampCal - Utvärdering av mätmetoder för temperatur, viskositet och densitet samt röregenskaper
The dissertation were performed on SP, Technical Institute of Sweden.
The dissertation were carried out on the measurement technical department, this dissertation is a part of a bigger project, project ClampCal.
One of SP?s returning assignments are flow-measurement. When flow-measurement is performed, the flow has to be stopped so that a meter can be installed in the pipes where measurement is going to take place. At every stop there is time delay in the flow which causes the customers to loose money. This is why SP wanted to find a better solution so that measurement can be done without any stops in the flow.
Usage of a so-called Clamp-on meter was considered, but since the measurement uncertainty is too large it takes some investigation on the parts where the largest Uncertainties occur and thus find a solution that can diminish the uncertainty as much as possible.
The parts that were considered to have an opportunity to reduce measurement Uncertainties were the fluid temperature, its characteristics and the pipe geometry and its characteristics.
For the fluid temperature a Pt100-sensor with four different radii for various pipes was used.
Att falla för grupptrycket - Hur unga entreprenörer kan sälla sig till kluster för att hantera osäkerheter rörande företagande
Tidigare forskning har visat att det finns ett stort intresse bland unga i Sverige att starta företag. Det har också uppenbarats att det finns brister i ungas kunskaper om företagande och entreprenörskap, och de vet inte heller hur de skall gå tillväga för få den kunskapen. De faktorerna påverkar ungas företagande negativt och hämmar dem i deras önskan om egenföretagande. Syftet med denna uppsats är att undersöka vilka specifika faktorer som hindrar unga från att starta företag, det vill säga vilka osäkerheter de upplever i den industriella omgivningen och hur de kan hanteras. I ett försök att finna metoder som hjälper unga att hantera de osäkerheter som upplevs har jag undersökt hur klusterteorin kan underlätta företagandet.
Skattning av den integrerade hydrauliska konduktivitetens variation kring Tunåsens infiltrationsanläggning : En utredning av påverkan från möjliga osäkerheter i befintlig information
Estimation of the variation in the integrated hydraulic conductivity around the Tunåsen infiltration facility - An investigation of the effects of Uncertainties in existing informationAlmost half of Sweden?s drinking water volume is produced from groundwater. The main fraction of this is extracted from eskers, some of which allow for very large extraction rates. Despite this, the groundwater volume is not sufficient in some areas. This has led to an extensive use of artificial recharge.In Uppsala, the total volume added through artificial recharge is divided between four infiltration facilities.
Arboga Mekaniska Verkstad : Förslag på saneringsåtgärder gällande gjuteriet och plåtverkstaden
The industrialization in Sweden has increased the large number of areas that have been contaminated with various types of pollution. One of those sites are the property Höjen 3:24 in Arboga where ?Arboga Mekaniska Verkstad? once been. The property wants to increase the use of the old former foundry building with the adjacent ?plate-workshop? and believe there are two options for the building: That the building either should be used as a warehouse/concert hall, or rebuilt into a cultural center. An environmental evaluation has shown that the levels of heavy metals are over the Swedish environmental protection agency guidelines of less sensitive land.
Investment in project preventing deforestation of the Brazilian Amazonas
The aim of this thesis is to create an understanding of the incentives for forest companies to invest in reducing carbon dioxide emissions from deforestation and forest degradation, which is termed REDD. The Brazilian Amazonas was chosen as the base for the investment case. Brazil has the largest area of rainforest in the world, and also the biggest problem with deforestation. The Amazon region of Brazil comprises rainforest which is largely intact and unexploited. Accordingly, there is significant potential scope for prospective investments in a REDD-project, and so have a noteworthy impact in preventing deforestation.The research approach used the United Nation?s Clean Development Mechanism concept was used as a framework for ascertaining the investment costs in potential REDD-projects.
Osäkerheter vid riskanalyser i samband med transport av farligt gods
Risk analysis in connection with transportation of dangerous goods is associated with great uncertainty. In addition there are a number of specific problems that the risk analyst faces when risks associated with transportation of dangerous goods are to be analysed. In this report those problems and Uncertainties are described.One of the most important conclusions in this report is that uncertainty analysis within risk analysis in connection to transportation of dangerous goods has to be made more effective..
Texturbestämning genom fält-, pipett- och hydrometermetoder :
Texture is an important soil property and accurate particle size analysis of soil texture is therefore crucial. There are a number of well-established and newly developed methods available for determining soil texture. In order to compare the results of these methods, the differences between them must be determined.
The difficulties, problems and differences regarding texture class determination were examined through a study performed on forest soil samples. The study compared different methods (pipette, hydrometer and field methods) and two types of dispersing agents (sodium pyrophosphate and sodium hexametaphosphate (calgon)) commonly used for particle size analysis.
Statusbedömning av asynkronmotorer
Induction motors, often referred to as the workhorse of the industry, play an important role in production today. Therefore, it's important to diagnose any faulty induction motor prior to failure to avoid costly and time consuming production stops.This thesis compares methods for diagnosing induction motors in operation, MCSA, Park's vector approach and the standard method used by Swedish industries today. By simulating broken rotor bars and short-circuit in one of the windings, each method is tested and the results are compared using matlab.The results need further verification due to Uncertainties of the condition of the test motor, even though the experiment gives a hint of the different advantages of each method. A combination of the methods should be able to tell if the motor needs further examination..
Ethanol for Scania's Future - A Scenario Based Analysis
Abstract Title: Ethanol for Scania?s future ? A scenario based analysis Authors: Anna Hansson and Julia Persson Tutors: Annette Cerne ? Department of Business Administration, Lund University Jonas Holmborn ? Head of Advanced Combustion, Engine Development, Scania Lennart Thörnqvist ? Department of Energy Sciences, Faculty of Engineering, Lund University Problem: Oil-based products are the dominating fuels in the transport sector but alternative fuels are currently challenging the world-wide dominance. The large number of alternative fuels that are under development at present makes the future fuel-market impossible to predict. Scania?s ethanol project is associated with a number of uncertainty factors that are beyond the company?s control.
Biomekaniska berättelser : En analys av forskningkommunikationen runt den biomekaniska armen
The pdf is excluding images, because of Uncertainties regarding copyrights. Instead I have put links for each picture so you may find them on the Internet. For a list of links to the online sourcematerial, please visit http://del.icio.us/Cyborguppsats.