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14436 Uppsatser om Analogy time estimation method - Sida 2 av 963
En indirekt metod för adaptiv reglering av en helikopter
When a helicopter is flying, the dynamics vary depending on, for example, speed and position. Hence, a time-invariant linear model cannot describe its properties under all flight conditions. It is therefore desirable to update the linear helicopter model continuously during the flight. In this thesis, two different recursive estimation methods are presented, LMS (Least Mean Square) and adaptation with a Kalman filter. The main purpose of the system estimation is to get a model which can be used for feedback control.
Utveckling och implementering av ett audiopejlsystem baserat på tidsdifferensmätning
The use of spread spectrum signals has increased dramatically in military applications. Finding methods for detecting and positioning of these signals have become interesting research areas for signal intelligence purposes. One method is to measure the time difference of arrival (TDOA) that occurs when two receivers are synchronous and spatially separated. Based on the TDOA-technique an audio-demonstrator has been developed and implemented. This report describes the theory for how sound received in microphones can be used to extract information about the transmitter?s position from the measured time difference.
Diskontinuerliga Galerkinmetoder för initialvärdesproblem och prissättning av optioner
Efficient numerical methods for option pricing is an active field of research. This project has the goal to examine possible ways to improve an established method of numerical pricing. The method is based on an adaptive finite difference method in price and uses the backwards differentiation formula of order 2, BDF2, in time. The project will focus on improvements to the time integration through implementation of discontinuous Galerkin methods, dG. Empirical convergence and accuracy results are obtained for equidistant dG-methods up to order 3 and performance is compared to BDF2.
Korrelation mellan hållfasthet i kalkcementpelare och oförstärkt lera : En studie av sonderingar utförda på projekt BanaVäg i Väst
A today common soil reinforcement method is the installation of lime-cement columns. Lime-cement columns have been used since the 1970?s and have been a useful method for stabilizing soil at great depths. It is mostly used for stabilizing road and railway embankments because the method is economically viable and the columns are easy to install. The total costs for the installation of the lime-cement columns is dependent on the numbers of installed columns, what percentage of lime and cement that has been used and the pattern in which the columns has been installed.
I Gripdjurets grepp : om skandinavisk djurornamentik, bildtolknings metodik och djurhuvudformiga spännen
Animal art is one of the more mystical aspects of Scandinavian Iron Age culture. It has foremost been regarded in the light of art and style history. Interpretation has also ? mainly from the 1990s and onwards ? been made through iconographic analysis. But the problem here is that iconography requires textual analogy, something that the Scandinavian Iron Age lacks.The purpose of this paper is to lift some of the ?mystical fog? that engulfs the scandinavian animal art, by developing a method for interpretation of pre-historic images that evades the flaws in the iconographic method.
Total hälseneruptur: Resultat efter operativ respektive konservativ behandling.
ABSTRACTBackground: On behalf of the Orthopedic clinic, Västerås, a study has been conducted with focus on comparing the results after conservative and surgical treatment due to complete achillestendon rupture.Aim: To compare results when testing the active and passive range of motion, calf muscle endurance, estimation of pain related to the achillestendon and self-efficacy to be physically active for individuals who have undergone conservative or surgical treatment after complete achillestendon rupture.Method: 14 individuals afflicted by complete achillestendon rupture in 2010 were recruited as a purposive sample. Examination were conducted of: Ankle range of motion with a goniometer, calf muscle endurance through a toe-raise test, estimation of pain intensity related to the achillestendon by VAS and self-efficacy to be physically active through ?Exercise self-efficacy scale?. P-value and the median were calculated.Result: The results of ankle range of motion and calf muscle endurance were based on the difference between the injured and the healthy side. When testing active plantarflexion the conservative group had a median of 4 ? and the surgical group had a median of 10 ?.
Tillståndsskattning i robotmodell med accelerometrar
The purpose of this report is to evaluate different methods for identifying states in robot models. Both linear and non-linear filters exist among these methods and are compared to each other. Advantages, disadvantages and problems that can occur during tuning and running are presented. Additional measurements from accelerometers are added and their use with above mentioned methods for state estimation is evaluated. The evaluation of methods in this report is mainly based on simulations in Matlab, even though some experiments have been performed on laboratory equipment.The conclusion indicates that simple non-linear models with few states can be more accurately estimated with a Kalman filter than with an extended Kalman filter, as long as only linear measurements are used.
Skattning av fordonsmassa med driftstatistik
In the automatic manual transmission system, Opticruise, the choice of gear is based on several parameters such as road incline, driving resistance and vehicle mass. Many different mass estimations are made during driving. A final vehicle mass is then used to determine the current gear. Construction vehicles are often not equipped with air suspension and can therefore not estimate the vehicle mass when standing still. If that sort of vehicle is reloaded while standing still an incorrect mass estimation will be used and as an effect of that also a wrong gear.
Utvärdering av Transportstyrelsens flygtrafiksmodeller
The Swedish Transport Agency has for a long time collected data on a monthly basis for different variables that are used to make predictions, short projections as well as longer projections. They have used SAS for producing statistical models in air transport. The model with the largest value of coefficient of determination is the method that has been used for a long time. The Swedish Transport Agency felt it was time for an evaluation of their models and methods of how projections is estimated, they would also explore the possibilities to use different, completely new models for forecasting air travel. This Bachelor thesis examines how the Holt-Winters method does compare with SARIMA, error terms such as RMSE, MAPE, R2, AIC and BIC will be compared between the methods. The results which have been produced showing that there may be a risk that the Holt-Winters models adepts a bit too well in a few variables in which Holt-Winters method has been adapted.
Bostadssektorns koldioxidutsläpp
Energy is an important issue in the current world which significantly affects sustainability and development. Energy generation and use are major sources of CO2 emissions which is one of the most important driving factors in global climate changes. The amount of energy used in house hold section can lead to estimation of the amount of CO2 emitted within this section which subsequently would be a ground to better management and maintaining a sustainable society. This study which is a bachelor?s project in sustainable energy, deals with estimation of CO2 emission from different types of residential houses in Sweden. An extensive literature review on energy use in Sweden by different residential sectors has been conducted.
Förbättring av mjukvarubibliotek för parallellberäkningar med programmeringsmodellen Chunks and Tasks
Chunks and Tasks is a programming model based on the C ++ programming language. This programming model is used for electronic structure calculations, among other things.The purpose of this project is to improve the CHT-MPI software library for Chunks and tasks, so that calculations of matrix-matrix multiplications are performed more efficiently than they do with the existing software library. The software library is based on the work stealing method, which is a method the software library for Chunks and Tasks uses for the distribution of the calculation work. The considered way to improve the software library is by modifying the work stealing method in a way that makes the distribution of calculation work happen in a more efficient way , which will lead to calculations performed faster than before.Two different modifications of the work stealing method were tested and it led to two new methods, Method 1 and Method 2, which distributed the calculation work differently. Method 1 did not give results that were compatible with the theory, since the calculation time with this method was much longer than the previous method.
Möjligheter och begränsningar med läroboksbaserad och laborativ matematikundervisning
Mathematics is a central topic in today's education debate, including discussion of its educational quality and various teaching methods. Today basically two different teaching methods are used; one is the textbook based method, with the book in focus and the other one the laboratory method by which teaching is performed through practical applications. The purpose of this study was to examine four primary school teachers' view of these two teaching methods by means of four relevant inquiries. By interviewing the four teachers, advantages and disadvantages were highlighted and the purpose was achieved. In order to support the analysis, two theories applied; the socio-cultural perspective and the cognitive perspective.
Gäddan & fisket i Ringsjöholm : en osteologisk metodstudie i säsong & bevarande
This paper presents the results from an osteological method study of the Ringsjöholm fishbone material. Ringsjöholm is located in Scania, southern Sweden and is 14C dated to 5960-5200 B.P. The aim of this paper is to critically analyse methods used on fish bone material in estimations of season. Three different approaches were used to estimate the fishing season at the Ringsjöholm settlement; 1) identified species, 2) size estimations of the pike based on Enghoffs (1994-95) regression formulae of os dentale, and 3) growth rings of the pike vertebrae.The identified species and the size estimations of the pike points to the fishing being active both during spring and summer. Growth rings analysis of the pike vertebrae didn?t give any quantitative results because of fragmentation.
Enumerating Atlantic salmon smolt production in River Vindelälven based on habitat availability and parr densities : consequences of using different density estimation methods
Habitat mapping was conducted in the main stem of River Vindelälven in the autumn of 2009 along the salmon distribution area. The aim was to estimate the quantity of potential reproduction areas, including spawning and juvenile rearing habitats. The mapping included 61 km of various stream sections along the river length of 269 km. The total area of stream habitats was estimated to 647 ha of which 396 ha (61%) were considered as either potential or optimal juvenile nursery habitats. The area of these two habitat classes were used to estimate the smolt production in the river by using electro fishing densities of juveniles (0+ per 100 m2).
Scintigrafisk undersökning av esofagusmotilitet hos häst :
Scintigraphic examination of the esophagus has for some time been the method of choice for the study of motility dysfunction in humans. The method has not yet been described for horses hence the lack of reference values for passage time for a bolus through the esophagus in healthy subjects. The purposes of this study were to measure passage velocity and time for a bolus to pass through the esophagus in healthy subjects, as well as to evaluate the reproducibility of the method. Eight warm-blooded trotters were used in the study. The horses were sedated with a low dose of Acepromazine prior to onset of the study.