Sök:

Sökresultat:

8742 Uppsatser om System of equations. - Sida 1 av 583

Tillförlitlighet hos information som hanteras av flera användare och genom flera system

When investigating mechanical problems it is often more convenient to deal with scalars rather than vectors. In this project methods stemming from the field of analytical mechanics, which lets one derive the equations of motion using scalar quantities instead of vectors, have been used. Two mechanical problems were investigated, a double pendulum with a spring and particles orbit in a sphere. The equations of motion of the two systems were derived with the assistance of computer algebra, using Maple and the external package Sophia. The systems were investigated with regard to periodicity and conserved quantities..

Asymptotiska egenskaper för Lanczosspinoren

Asymptotically flat spaces are widely studied because it is one natural way of describing an isolated system in general relativity. In this thesis we study what happens to the Lanczos potential at spacelike infinity in such spacetimes. By transformations of the Weyl-Lanczos equation, we derive expressions for the limiting equations on both the timelike unit hyperboloid, and the timelike unit cylinder. Finally the Newman-Penrose formalism is used to get a component version of the equations..

Vilometabolism hos barn och ungdomar med Cerebral Pares : En deskriptiv korrelationsstudie

Background: Cerebral Palsy is usually divided into three subgroups: ataxic, spastic and dyskinetic, where children and adolescents can, because of misestimation in nutrition and energy intake, suffer from weight problems.Aim: To compare calculations with equations with the individual's measured RMR in the subgroups, to see if any equation is more suitable. This could be used as a tool to calculate the resting metabolism at times when it is not possible to perform clinical measurements.Method: The RMR has been measured in 37 children and adolescents aged 3-15 years through indirect respiratory calorimetry. Those values have been compared with calculations from five equations. The results were then analyzed in order to find if any equation is better to apply for calculating resting metabolism for each subgroup.Results: The ataxic group was overestimated by 56.5% of the calculated values. WHO/FAO/UNU?s equation indicates a significantly strong correlation between the measured and calculated values (r=0.85, p<0.05).

Undersökning av Mekaniska Problem med hjälp av Datoralgebra

When investigating mechanical problems it is often more convenient to deal with scalars rather than vectors. In this project methods stemming from the field of analytical mechanics, which lets one derive the equations of motion using scalar quantities instead of vectors, have been used. Two mechanical problems were investigated, a double pendulum with a spring and particles orbit in a sphere. The equations of motion of the two systems were derived with the assistance of computer algebra, using Maple and the external package Sophia. The systems were investigated with regard to periodicity and conserved quantities..

Volume and taper equations for Sitka spruce (Picea sitchensis (Bong.) Carr.), Norway spruce (Picea abies (L.) Karst.) and White spruce (Picea glauca (Moench) Voss) in Iceland

The aim of this study was to evaluate different types of volume and taper equations that can be used to predict single-tree stem volume and stem diameter at any given height along the tree stem for plantation grown Sitka spruce (Picea sitchensis (Bong.) Carr.), Norway spruce (Picea abies (L.) Karst) and White spruce (Picea glauca (Mounch) Voss) in Iceland. A number of published tree volume equations were tested and modified to predict the total stem volumes over bark but three logarithmic equations were taken for more in-depth analysis. Three taper equations were tested. Two variable-exponent equations (Kozak 1997, Kozak 2004) and one exponential equation described by Biging (1984). Data from a total of 617 sample trees were used in this study, collected from stands in various parts of the country and present different types of stands growing in different soil types and cover most of the site conditions suitable for forestry in Iceland.

Avbördningsekvationer för sjöar utan vattenföringsmätningar

Stage-discharge equations for lakes without disharge measurementsSimon AnderssonIn 2015 all lakes, rivers, coastal water and groundwater should be of good ecological statusaccording to the water framework directive from the European Union. In the process ofimproving the quality of Swedish water bodies, knowledge of where problems occur isneeded in order to utilize the resources optimally. The ability of lakes to store water is animportant factor since it controls the flow of water through the country. A stage-dischargeequation is a mathematical relation between discharge from a lake and its water level. Bybetter understanding of stage-discharge equations for lakes, their storage capacity can bedescribed better in hydrological models.This master thesis aims to evaluate methods for determining stage-discharge equations forlakes where a variable amount of field measurements is available.

Förbättringsarbete på monteringsbana

In this project we have used the theory of analytical mechanics to derive equations of motion for complex mechanical systems in order to study their behaviour over time. Even if the theory provides powerful tools to tackle tough problems which would be very hard to solve by methods of Newtonian mechanics, you are still relatively limited without running any computer simulations. One realises that in a faster rate it will be an incredibly difficult task to find an analytical solution when the degrees of freedom increases. Even if one would succeed to derive the equations, one still has to solve them to get the information of the systems behavior. Of experience one knows that the equations in general are nonlinear and hence must be integrated numericaly.

Analytisk mekanik med datoralgebra

In this project we have used the theory of analytical mechanics to derive equations of motion for complex mechanical systems in order to study their behaviour over time. Even if the theory provides powerful tools to tackle tough problems which would be very hard to solve by methods of Newtonian mechanics, you are still relatively limited without running any computer simulations. One realises that in a faster rate it will be an incredibly difficult task to find an analytical solution when the degrees of freedom increases. Even if one would succeed to derive the equations, one still has to solve them to get the information of the systems behavior. Of experience one knows that the equations in general are nonlinear and hence must be integrated numericaly.

Modellering och simulering av hovrande helikopter

At the department of Electronic Warfare Assessments at the Swedish Defence Research Agency in Linköping one of the activities is modelling and simulation of the duel between a robot and a target. The aim with this Master's thesis is to develop a simulation model of an hovering helicopter. First a theoretical description of the forces and moments acting on an helicopter is given. Then the equations of motion are derived. These equations are simplified to be valid only for a hovering helicopter and the result is a mathematical model.

Modellering, identifiering och reglering av skannern i ett laserbatymetrisystem

The purpose with this masters thesis was to model the scanner in a system for laser bathymetry. The model was then used to develop a controller for the scanner so a good search pattern was achieved. Two different types of models have been tested, a physical model and a Black Box model of Box Jenkins type. The physical model has been derived from Lagranges equations. Identification experiments have been used to compute the Black Box model and to find the unknown parameters in the physical model.

Fluid Simulation for Visual Effects

This thesis describes a system for dealing with free surface fluid simulations, and the components needed in order to construct such a system. It builds upon recent research, but in a computer graphics context the amount of available literature is limited and difficult to implement. Because of this, the text aims at providing a solid foundation of the mathematics needed, at explaining in greater detail the steps needed to solve the problem, and lastly at improving some aspects of the animation process as it has been described in earlier works. The aim of the system itself is to provide visually plausible renditions of animated fluids in three dimensions in a manner that allows it to be usable in a visual effects production context. The novel features described include a generalized interaction layer providing greater control to artists, a new way of dealing with moving objects that interact with the fluid and a method for adding source and drain capabilities..

Måltidsmönster, kost - och - medievanor bland överviktiga 15-åriga flickor och pojkar

Objective: The aim of this study was to compare equations used to calculate BMR to values of BMR obtained from measurements in order to determine the most suitable equation to be used on children and adolescents with CF.Design: The participants where children and adolescents with CF. Data was collected from the division of Clinical Nutrition at Uppsala Akademiska Sjukhus. Age, weight, height, BMI, BMR, FFM and FM was recorded from 27 measurements. BMR from the participants collected from the indirect respiratory calorimetry was compared to the results obtained from five equations used to obtain a calculated value of BMR.Results: Tverskayas equation was best correlated with the measured BMR for the whole group. The equation underestimated BMR for the participants with a measured BMR over 1400 kcal/24h and overestimated BMR for participants with a measured BMR under 1400 kcal/24h.

Algebra i skolan : En studie om elevers algebraiska kunskaper inom området ekvationer i årskurs 9

Algebra in school, - a study on students` algebraic knowledge of the field equations in ninth grade.International (TIMSS) and national mathematics studies detects that Swedish pupils math skills is deteriorating in comparison to other countries. Therefore has the subject of mathematics become one of the school subjects which are becoming increasingly in focus. The government has made a big effort, Matematiklyftet, in mathematics in primary education, 650 million has been invested and the Agency has been tasked to train all current mathematics teachers through peer collegial learning. This effort is the most pervasive in modern times in Sweden.The aim of this study is that we as prospective mathematics teachers want to find our approach to surveys results. By using the Governments? diagnoses, Diamant, student group interviews, teacher interviews and theories in mathematics education, we want to make students' algebraic knowledge of the field equations visible.

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.

En studie i röj

This paper presents a study of the computer game ?Minesweeper?. The aim of the game is to search through a rectangular area of mined squares without hitting any mines. By using a strategy based on making every operation as safe as possible, series of the game have been simulated. The size of the playground is four times four squares.

1 Nästa sida ->