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4090 Uppsatser om Load model - Sida 8 av 273
Underlag för bedömning av energibrunnar inom vattenskyddsområde
Denna rapport beskriver arbetet med utvecklingen av en ny modell för kaplanturbiner. Utvecklingen bygger på två kopplade differentialekvationer som under arbetets gång anpassats och implementerats i turbinmodellen.Modellen beskriver hur vattenflöde och turbinmoment påverkas av avvikelsen från den optimala kombineringskurvan för vinklarna på turbinens ledskena och löphjul, och är anpassad för ett referensaggregat med tillgängliga provdata. Även övriga enheter i vattenkraftaggregatet modelleras och sätts samman med frekvensregulator och elnät för att simulera aggregatets reglerstabilitet i önätsdrift.Verifieringen av turbinmodellen sker genom försök att återskapa de befintliga verkningsgradskurvorna med hjälp av modellen. Resultatet visar en god följning av de verkliga kurvformerna, dock med något lägre maximal verkningsgrad.Verifieringen av önätmodellen sker genom att prova stabiliteten i nätfrekvens och turbineffekt vid stegpålastningar. Resultatet ger en stabilare reglerstabilitet än i verkligheten, men uppfyller ändå förväntningarna på en fungerande modell.This report describes the development of a new kaplan turbine model.
Undersökning av elkvalitet i distributionsnät med omfattande vindkraftselproduktion
The goal for this master thesis project has been to investigate the power quality in adistribution grid, which has a high fraction of dispersed power production due towindmills. The study has been done on a grid in Laholm South of Halmstad, whereapproximately 45 windmills are connected to the distribution grid owned by SHKEnergi. The investigation has been focused on to two radialy fed 20 kV lines, wheretwelve windmills are connected.Voltage variations have been studied by creating a model of the grid in the simulationprogram SIMPOW. The largest deviation that has been found in any point of the gridis ±1.9 % of the nominal voltage. This deviation is a result of varying powergeneration from the windmills and the voltage regulation at the connection point ofthe line.
Kinematisk och dynamisk modellering av den haptiska enheten TAU i sex frihetsgrader
The thesis presents an optimally designed kinematic structure for a new 6-DOF haptic devicebased on TAU configuration. The configuration of the TAU-2 proposed by Suleman Khan andKjell Andersson [1] was modified and its mobility was verified by using Grübler criterion tohave a 6 DOF. Analytical kinematic models for the inverse and forward kinematics weredeveloped for the haptic TAU configuration to determine a set of optimal design parameters.Kinematic performance indices such as volume of the workspace, kinematic isotropy and payload index, were defined based on the singular values of the Jacobian matrix. The Jacobianmatrix was scaled to homogenize the physical units. The Jacobian matrix dependent on theposition and orientation of the end-effector gives local isotropy and pay load index, so globaldesign indices were defined, which represent the performance of the mechanism in the wholeworkspace.
Livscykelbaserad miljövärdering av en ny kontorsbyggnad : En jämförande studie mellan två analysmetoder
This Master?s Thesis aims to illustrate in what ways the two Swedish environmental assessment tools, the Environmental Load Profile and EcoEffect differ and if performed valuations gives different results and environmental goals.The built urban environment causes about half the environmental loading in Sweden. The society?s ambition towards sustainable development has resulted in demands reducing the environmental load. One way to accomplish this change is with the assistance of tools for environmental assessment of the built environment.
Hudiksvalls samordningsmodell- en modell för att underlätta samverkan?
AbstractHudiksvalls coordinating model - a model to make cooperation easierCamilla Andersson and Åsa GradinThe purpose of this study was to examine the experience each one of the administrators have of their own new model in Hudiksvall to make cooperation easier for the three different administrations in Hudiksvalls municipality. The study will focus on the administrators experiences of Hudiksvalls coordinating design. Questions of the study were: How is the influence of the model on the rules? How is the influence of the model on expectations and parts? What kind of influence did the model have on the responsibility distribution? What kind of influence has the model on the responsibilities at the transfer of costs? To answer the questions of the study we applied a qualitative method, it was made through a standardization interview guide and open questions, with six of the dealing officers who works with the model. Some of the results wich can be discern are by an economic character, andfor the clients that they won`t be passed around the administrations in the community, they get the right help, quick and safe.Key words: cooperation, coordination..
Simulering av filtrerade skärmfärger
This report present a working model for simulation of what happens to colors displayed on screens when they are observed through optical filters. The results of the model can be used to visually, on one screen, simulate another screen with an applied optical filter. The model can also produce CIE color difference values for the simulated screen colors. The model is data driven and requires spectral measurements for at least the screen to be simulated and the physical filters that will be used. The model is divided into three separate modules or steps where each of the modules can be easily replaced by alternative implementations or solutions.
Modellering av rotationssystem
This master thesis was conducted during the spring of 2014 at Atlas Copco Rock Drills AB in Örebro. The purpose of the thesis was to develop a simulation model of the rotation system for a hydraulic rock drill. In the future, the model will be used to investigate the phenomena called ?jerky rotation?. In order to validate the simulation model a test bench was designed and tests were made.
Analys av designalternativ för snabbare dynamik i kolkraftverk med koldioxidavskiljning
Combustion of fossil fuels is today the dominating source of energy. During combustion,carbon dioxide is formed. The carbon dioxide accumulates in the atmosphere,which raises the global average temperature on earth through the so called greenhouseeffect. The only way to reduce the emissions of carbon dioxide from combustionin a coal fired power plant is through carbon capture and storage (CCS).Post-combustion capture is a technology to separate carbon dioxide from the uegas after the combustion for efficient transport and storage. The steady state operationof coal fired power plants with post combustion capture has already beenthoroughly investigated on a pilot scale, however much work remains to investigatethe plants dynamic operation.
Jämförelsestudie för tre olika metoder att beräkna genomstansning i betong : Skillnader i genomstansningskapacitet för metoderna i BBK04, EK2 och BHB
Before the European construction standards were introduced in January 2011, it was mainly themethod in BBK04 that was used for calculating punching capacity in concrete structures, and in lesscommon cases the method in BHB. The method of BBK04 is easy to use and have had the samestructure since the first was published in 1979. The Concrete handbook method (BHB) where usuallyonly used when a higher punching capacity was needed and the cross-sectional height where fixed,calculations using this method entails more work, but will in return usually give a higher capacity. Italso allows the use of shear reinforcement to increase the cross-section capacity. The method ofcalculating punching shear in EC2 differs largely from the methods of BBK04 and BHB.
Värmning av avloppsvatten med spillvärme för att förbättra kvävereningen -Temperaturens inverkan på kvävereningen
The goal for this master thesis project has been to investigate the power quality in adistribution grid, which has a high fraction of dispersed power production due towindmills. The study has been done on a grid in Laholm South of Halmstad, whereapproximately 45 windmills are connected to the distribution grid owned by SHKEnergi. The investigation has been focused on to two radialy fed 20 kV lines, wheretwelve windmills are connected.Voltage variations have been studied by creating a model of the grid in the simulationprogram SIMPOW. The largest deviation that has been found in any point of the gridis ±1.9 % of the nominal voltage. This deviation is a result of varying powergeneration from the windmills and the voltage regulation at the connection point ofthe line.
TOMO Hugglink
Tomo Hugglink (TOMO Skog) is an innovation for harvest and transport of biofuels. The system consists of a truck, a chipping unit and crane mounted on a link and a wood chip trailer. The system works in such a way that the chipping unit is disconnected and placed on the site and wood chips are loaded directly into the wood chip trailer.The aim of this study was:- To examine the performance of the TOMO Hugglink system under different conditions such as the size, placement and quality of the pile.- To calculate the cost per raw ton for two vehicle combinations at different transport distances and to examine the effect of a reduction in set-up time and an increase in load weight.- To identify possible improvements with the TOMO Hugglink system.A time study was conducted within the thesis work to make it possible to determine production and time consumption. In the subsequent economic analysis the cost per tone at different transport distances was calculated for two different lorry concepts. Furthermore the effect of a reduction in set-up time and an increase in load weight was calculated.Under current conditions the utilization of the chipper is low and only 29 % of the total system time is occupied by chipping.
Prognostisering av räntabilitet på eget kapital - En jämförelsestudie av tre regressionsmodellers prognosförmåga applicerat på svenska data
A multivariate cross-sectional model is used in this thesis to proxy for expected earnings and to estimate return on equity for 214 companies over the period 2009-2013, using Swedish data. The model, which has never been tested on Swedish data before, is first confirmed to function as a forecasting model for expected return. Furthermore, the model is evaluated through a comparison with two univariate models based on the assumption that return on equity follows a mean reversion process. Forecast accuracy is calculated as the difference of estimated returns and actual returns. The results show that the univariate models' forecasts are superior to the multivariate model's..
Den moderna kommunikationen : En rapport om instant messaging och hur det används av unga vuxna studenter.
This paper describes the development of a simulation model for the ambulance flow in the Västra Götalands-region of Sweden, and an analysis tool for the output of the simulation model. The aim of the simulation model was to be able to evaluate the outcome from changes in the ambulance operations, such as a reorganization of ambulances or an increase in intensity of the ambulance calls. This evaluation is meant to serve as decision support for the strategic planning of the ambulance operations. The analysis tool was developed to visualize the abundant geographical data produced by the simulation model in a meaningful way. The simulation model was validated against historical data which showed that the dispatch time for the highest prioritized ambulance calls corresponds well with historical data.
Kommunikationsstrategi för Renbruksplan : är det en fungerande modell för samebyarna vid samråd?
The reindeer planning system (Renbruksplanen, RBP) is a communication and planning tool designed for Sami groups. A key purpose of this is that it will act as a tool in consultation with other market players, including forestry. Sami groups have asked for a model of how this can be used in a flexible manner. With the Swedish Forest Agency as a project manager, a communication model for how to use the RBP has been designed. It consists of a number of points divided into ?before?, ?during? and ?after? the consultation.
Avancerad scenarioanalys för ambulansplanering
This paper describes the development of a simulation model for the ambulance flow in the Västra Götalands-region of Sweden, and an analysis tool for the output of the simulation model. The aim of the simulation model was to be able to evaluate the outcome from changes in the ambulance operations, such as a reorganization of ambulances or an increase in intensity of the ambulance calls. This evaluation is meant to serve as decision support for the strategic planning of the ambulance operations. The analysis tool was developed to visualize the abundant geographical data produced by the simulation model in a meaningful way. The simulation model was validated against historical data which showed that the dispatch time for the highest prioritized ambulance calls corresponds well with historical data.