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1854 Uppsatser om Standard deviation - Sida 2 av 124

Studier av utseendet på askan i sodapannor med hjälp av bildanalys

To reduce emissions of carbon dioxide (CO2) Carbon Capture and Storage (CCS) technologieshave been developed. Chemical Looping Combustion (CLC) is a CO2 capture technologywith the CCS framework, and at Chalmers University of Technology in Gothenburg,Sweden, a 100 kW chemical looping combustor has been built.This project aimed to investigate to what degree air can replace helium as the uidizinggas for uid dynamical studies in a CLC cold ow model of the above mentioned 100 kWfacility. Experiments were performed using air and helium separately as uidizing gas andpressure data were obtained, which formed the basis for the comparison. The project alsoaimed to investigate uid dynamics in the uidized bed and study when the risk of sluggingoccuring was greatest. The results were presented in the form of figures and tables dividedinto pressure, concentration and Standard deviation of the pressure.The results obtained showed that air as uidizing gas did not create the same uid dynamicsas helium over the entire fuel reactor.

En jämförande studie av fluiddynamiken för olika fluidiseringsmedium i en kallmodell av en 100 kW-anläggning för kemcyklisk förbränning

To reduce emissions of carbon dioxide (CO2) Carbon Capture and Storage (CCS) technologieshave been developed. Chemical Looping Combustion (CLC) is a CO2 capture technologywith the CCS framework, and at Chalmers University of Technology in Gothenburg,Sweden, a 100 kW chemical looping combustor has been built.This project aimed to investigate to what degree air can replace helium as the uidizinggas for uid dynamical studies in a CLC cold ow model of the above mentioned 100 kWfacility. Experiments were performed using air and helium separately as uidizing gas andpressure data were obtained, which formed the basis for the comparison. The project alsoaimed to investigate uid dynamics in the uidized bed and study when the risk of sluggingoccuring was greatest. The results were presented in the form of figures and tables dividedinto pressure, concentration and Standard deviation of the pressure.The results obtained showed that air as uidizing gas did not create the same uid dynamicsas helium over the entire fuel reactor.

En jämförelsestudie av AP-fonderna och bankernas Sverigefonder 2003-2010

Background: In 1999 the Swedish pension system was reformed with an aim to create a stable and high return on pension assets. First, Second, Third and Fourth general pension funds, hereby referred to as AP1-AP4, had an important part in the reform. AP1-AP4, also called the buffer funds, was assigned to secure long-term, big parts of the pension capital. The funds objective is by law, to manage the fund's assets in a manner that provides maximum benefit for the state pension. The funds will also invest pension assets with an overall low level of risk while achieving a sustainable high return.Aim: The purpose of this study is to investigate whether the First-Fourth AP-Funds is meeting its objectives regarding risk and return according to Swedish law.

Bestämning av osäkerheten hos skattningar av tyngdaccelerationen

In this master's thesis the problem of determining the uncertainty for an estimator of an unknown parameter is considered. The case we study is the estimation of gravity using a reversible pendulum. This involves the estimation of the point where two regression lines intersect. The estimated gravity is a function the coordinates of this point. One way to determine the uncertainty of this estimator is to use bootstrap methods.

Riskens förändring för svenska aktier och obligationer: 1919-2003

Purpose The purpose of our study was to investigate the changing nature of volatility during the last 80 years. Like in an American study, we tried to find some trends in the risk of stocks and bonds that would have an impact on the balance of a portfolio of stocks and bonds. At the same time we investigated the influence of inflation on the choice of portfolio. Methods We have used standard statistic tools and formulas to obtain our results. In most cases it was a matter of calculating average and Standard deviation.

Förbättrar en kvalitetssäkring skördarens dimensionsmätning?

In this study it was investigated if the adoption of a new routine for quality control could improve the precision of the dimension measurement obtained by harvesters. Data was collected from three different harvesters. First, a reference data set was collected before the new procedures had been incorporated, and then when the new methodology was implemented another data set was collected by the harvester operators, allowing the two data set to be compered. The results indicated that following the implementation of the new procedures, the reliability and the precision of the measurements has increased. All harvesters included in the study had improved regarding most of the controlled factors such as Standard deviation, systematic difference and hit rate within ± 2 cm for length and ± 4 mm for diameter..

Introduktion till icke-standard analys - Ett bevis av transferprincipen och en explicit konstruktion av Brownsk rörelse

I denna rapport konstrueras inledningsvis hyperreella tal från reella tal. Vi definierar aritmetik för skuggor av hyperreella tal och presenterar en icke-standard teori för serier och konvergens utifrån denna konstruktion.Förfarandet generaliseras sedan genom att skapa en icke-standard modell till matematisk analys utifrån en mängdteoretisk modell i ZF, som ett led i konstruktionen presenteras teori för filter och ultraprodukter. Vi visar sedan transferprincipen och bygger upp internalitetsbegreppet för att studera relationer mellan standard ochicke-standard modellerna för att kunna härledda standardresultat från icke-standard resultat. Avslutningsvistillämpas teorin för att skapa en explicit icke-standard konstruktion av Brownsk rörelse och vi ger ett bevis föratt denna konstruktion är ekvivalent med standard formuleringen..

Analys av turbulensmodeller för CFD

This thesis has been a part of Forsmarks Kraftgrupp AB's evaluation of a turbulencemodel used in simulation of turbulent flow called PRNS (Partially Resolved NumericalSimulation). This model has promising properties and may be of use in savingcomputational resources. The purpose of this thesis was to analyze this model andcompare it with industrially applied models such as k-omega SST and LES (Large EddySimulations).PRNS works as a hybrid of the k-omega SST and DNS (Direct Numerical Simulation)where a constant, RCP (Resolution Control Parameter) with a value between 0 and 1are selected. This constant is then used in the calculations and determines thebehavior of the simulation. When RCP is set to zero the equation are the same as fora DNS simulation and when RCP is set to one the equations for k-omega SST issolved.

En framtida placering i Kinafond eller USA-fond? : Ett säkrare val för investeraren

To invest money in funds is increasing rapidly in popularity and one of the biggest reasons is that banks are offering a greater range of funds. Information about funds is always easy to find and it is easy to invest money in a fund because the bank takes care of all the management of the fund.The essay examines two funds from two different countries with an aim to choose the one with best potential yield. The first fund is entirely invested in North America and the second fund invests in Asia, with most of its possessions in companies from China. Both these funds invest in wellknown companies in respective region. The essay is limited to compare these funds with data from 2005 to 2009.Information was collected from Morningstar and Avanza Bank for the quantitative examination.

Abnorm avkastning utifrån Benjamin Grahams värdestrategi : Ett ex ante test för de svenska, amerikanska samt japansk aktiemarknaderna

Theability to beat the market is one of the most discussed topics in finance. Thereare very few investors that manage to accomplish this over longer periods oftime. Most of the financial research claims that this is impossible unless theinvestor increase the risk in the portfolio. However numerous of researchershave shown that it exist anomalies on the stock market which either indicatesthat the Capital Asset Pricing Modell (CAPM) or Fama and French three-factormodel fails to explain stock returns or that the market is not fully efficient.One investor that has claimed that the stock market is not fully efficient andthat it is possible to generate abnormal return is Benjamin Graham. Graham isone of the legends on Wall Street and he has shown that by using few variablesbased on public information, one can manage to beat the market over longer timeperiods.There arejust a few studies that have tested Graham?s criteria?s, however all of themindicates that they work but that the Standard deviation might be higher forthe portfolios.

Reglerstrategi för fria ventiler : ? Utveckling av en fyrtakts förbränningsmodell för att prediktera optimala ventilinställningar

As emission legislations across the world continuously pushes engine development forward,engineers constantly need to come up with and implement fuel saving technologies. During thelast decade, variable cam phasing has become a popular solution to increase gas exchangeefficiency. This configuration is typically mechanically constrained by camshaft limitations, anda solution to circumvent this problem would be to use a different valve actuation principle.One example of this is to use pressurized air controlled by electrical solenoids. Such a systemhas been developed byCargine Engineering and this provides the starting point for this work. Tobe able to operate the valvetrain on an actual engine, a control system is needed.

En kvalitetskontroll - Snustillverkaren Fiedler & Lundgren kvalitetstestas

This paper aims to describe the variation and develop a method to control the production for the product Metropol Kaktus from the snuff developer Fiedler & Lundgren. We are going to use the requirements from the product specifications as limits of the expected quality when we present methods to control the process. One method attempts to control during the process and the other attempts to maximize the number of products with strived quality before the process starts. Metropol Kaktus is a product produced with high quality, the mean weight is 20,023 gram and this is very close to the weight, 20 gram, which is reported in the product specifications. The variation in weight variable is less than what is reported in the specifications and the minimum weight is over the limit set by Livsmedelsverket.

Naturreservat : en bra naturvårdsåtgärd för att bevara enskilda arter och/eller bevara den biologiska mångfalden?

The examination of the adequate nature conservation methods in a natural reserve, to conserve a specific species and / or increase biological diversity is the subject of this study. This work is based on four species, that can be found during the Spring season, liverleaf, wood anemone, brimstone and woodpecker. The incidence and availability is studied and closely observed for these species in twenty forests, i.e. ten forests which are nature reserves and ten forests with the similar characteristics as the nature reserves habitat, but are not nature reserves in Gnesta mucipality, Södermanland. Measurements of the tree crown and the diameter of the tree trunks where noted to study how these factors could affect the outcome of the abundance and incidence of the four species.

LÖNSAMHETSKALKYL AV FUKTSÄKERHETSANSVARIG VID RENOVERING : En fallstudie av ett projekt där ByggaF-metoden har använts

The so called ?ByggaF-method? is a relatively new Swedish method to stop moisture from being built into a building. The method should prevent damages on buildings as a result of mould growth and moisture. The purpose of the method is to include moisture control in the entire constructionprocess, from the projecting phase and all the way to the management phase. Up until now, there is no proof if the method is profitable or not and no studies have been made on the topic.

Den viktiga barnlitteraturen : Om förskollärares uppfattningar kring normkritisk barnlitteratur

The purpose of this study is to find out what preschool teachers think about antisocial children's literature. Based on five qualitative interviews with teachers at a preschool that works with a standard critical approach. In order to fulfill my purpose with this study, I focused on how these teachers felt that it was important to use the standard critical children's literature in preschool. I wanted to find out what the teachers' thoughts were on the concept of standard critical children's literature and how and whether they use it in their daily activities. When I analyzed the results of my interviews I used the queer theories that include standard critical pedagogy and literature in preschool.

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