Sökresultat:
3824 Uppsatser om Hydraulic model - Sida 3 av 255
Effekter av bearbetningsdjup i plöjningsfri odling
In Sweden, reduced tillage usually means non-inversion tillage, where primary tillage is carried out using chisel ploughs or disc implements. Primary tillage method is mainly determined by the desired soil loosening and the handling of soil residues.
The effect of tillage depth was studied in field experiments in Skåne, Väderstad, Uppsala, Örebro och Västerås in different crops; spring oilseed rape, spring wheat, winter wheat and spring barley.The experiments generally had a randomized block design with the treatments mouldboard ploughing, deep chisel ploughing and shallow chisel ploughing, in some cases also shallow discing and no-tillage. In the experiments the following parameters were determined: seedbed properties, saturated hydraulic conductivity, penetration resistance, number of emerged plants and crop yield (all parameters were not determined in all experiments. Root growth and draught requirement were determined in two separate studies.
There were no significant differences between tillage depths in non-inversion tillage in seedbed properties, plant emergence or root development.
Undersökning av luftkvaliteten vid småskalig biobränsleförbränning i två kommuner med modellsystemet VEDAIR
An Internet application, VEDAIR, for estimation of air quality in regions with small-scale combustion of bio fuel has been developed by Swedish Meteorological and Hydrological Institute with financing from Swedish Energy Agency and Swedish Environmental Protection Agency. The model contains user interface and a coupled model concept where concentrations of atmospheric pollutions are calculated for regional, urban and local contributions. In this report the model is described and a first study of air quality considering PM10 (particles with a diameter less than 10 µm) in two Swedish municipalities, Vänersborg and Gnosjö, is introduced.According to the result, there are areas with poor air quality even in smaller Swedish municipalities, mostly due to high emission from buildings with older wood heating furnace without hydraulic accumulator.In Vänersborg three areas were analysed in VEDAIR for the year 2003: Vargön, Mariedal and the downtown district. In the whole municipality the upper evaluation threshold for PM10, which is defined as 14 µg/m3 for annual average, was exceeded due to background contribution of particles. In all areas, however, the concentrations of PM10 were less than the environmental quality norms.
Demonstrationsprojektets roll i framväxten av ny teknik: Fallstudier av två vindkraftprojekt
This report describes a synchronous machine model with magnetic saturation in d-axis, neutralconnection and electrical exciter interface for the transient simulator PSCAD/EMTDC. It hasbeen designed and verified in comparison to the regular machine model in EMTDC.The performance of the model is very good when incorporating a linear as well as a saturatedmagnetising inductance. The dynamic deviation is only thousandths to ten thousandths perunit. By using a cubic interpolation of the saturation curve, the model gives a good representationof the saturation effect. The open source code implementation of the synchronousmachine model gives the possibility to easily adapt the model to specific requirements.The derived model makes it possible to simulate a synchronous machine with its excitationsystems, e.g.
Modellering av en panna med rörlig rost :
The aim of this master thesis was to create a dynamic model for the processes in a solid fuel boiler of the moving grate type. Another aim with the model was to keep it as simple as possible but still able to catch the dynamics of the processes in the bedplate of the boiler. The creation of the model had its origin from drying and combustion equations used in earlier modeling work of boilers. The represented model has been used to simulate different kinds of disturbances in a boiler and different ways to control the boiler. These tests show that controlling a number of parameters in the bed of the boiler is an effective way to keep the grate stable during disturbances.
Adaptiv katalysatormodell för reglering
This master?s thesis describes the development of a model of the catalystsystem aiming at control by an MPC. A well functioning model, which is suitable in control purpose, is important while emission legislation become more and more hard to fulfill for the car manufacturers. Much research has been done in the field of physical modeling of the system, but in this work a linear adaptive time discrete ARX-model is developed and validated.The systems tendency to change its dynamic during usage implies that the model must be adaptive. The developed model proved to be well functioning and shows promising conditions for the MPC design.
Testbänk för motorbåtsdrev
Marinediesel has, to meet there customers needs for a suitable sterndrive to powerboats, developed a prototype. The prototype is currently in the testing phase. The opportunity to test the sterndrive under load inside the workshop has not previously been possible. Until now the drive has been tested in a test bench without any load on the propeller axle. The prototype has also been tested under real conditions mounted on a boat.The idea with my thesis was to create a test bench that can run around the clock in order to be able to test things like wear and service intervals and other things that require that the test interval is long.
Referensvåtmarker för uppföljning av växtnäringsretention i anlagda våtmarker
One of the environmental problems today in seas, lakes and streams is eutrophication. This is often caused by nutrients such as phosphorus (P) and nitrogen (N) that leak from agricultural areas. A measure to partly prevent the nutrient discharge is to construct or restore wetlands.In order to control the efficiency of nutrient reduction of existing wetlands in the county, the administrative board in Västra Götaland wants to find different criterias for reference wetlands. These reference wetlands should represent other wetlands and be used in future evaluations of reduction of nutrients and design of constructed wetlands. According to the administrative board in Västra Götaland the reference wetlands should have a catchment area of about 50 hectare consisting of at least 70 % arable land, to represent wetlands created to remove nutrients.
Modell av en synkronmaskin för PSCAD/EMTDC med magnetisk mättning i d-led och elektriskt gränssnitt för fältmatare
This report describes a synchronous machine model with magnetic saturation in d-axis, neutralconnection and electrical exciter interface for the transient simulator PSCAD/EMTDC. It hasbeen designed and verified in comparison to the regular machine model in EMTDC.The performance of the model is very good when incorporating a linear as well as a saturatedmagnetising inductance. The dynamic deviation is only thousandths to ten thousandths perunit. By using a cubic interpolation of the saturation curve, the model gives a good representationof the saturation effect. The open source code implementation of the synchronousmachine model gives the possibility to easily adapt the model to specific requirements.The derived model makes it possible to simulate a synchronous machine with its excitationsystems, e.g.
Analys, modellering och återskapande av fordonsdynamiska rörelser i tåg
The purpose of this thesis was to analyse, model and finally generate dynamic vehicular motions in a train. The objective with the analysis was to find important motions for a realistic train experience. The motions from the analysis were then weighted against possibilities for generation in a motion platform.A dynamic motion model was created to model the selected motions. The model was implemented in a simulation environment, more specifically MATLAB/Simulink. The simulation environment was used to simulate the model and to generate outputs to control a motion platform.
?Vad är det jag gör egentligen?? - om att med videons hjälp bli medveten om helheten
This project consists of an adaptation, trial and evaluation of a model for practicing. Based on prior research I created a model aiming mainly to raise a musician?s self- awareness around the different parameters a performance consists of. An additional wish was for it to simultaneously assist the musician in monitoring his or her progress. With video recording and self-evaluation as the two main parts I tried the model by using it over a period of three months.
Multipel regressionsanalys av variabler som paverkar BNP
In this report a model was constructed in order to determine how a number of covariates influence the gross domestic product, GDP. The covariates were chosen depending on their expected influence on GDP, for example education and life expectancy. The data used in this report are collected from the World Bank. The model to describe GDP has been calculated using multiple line arregression. In order to reach a reliable final model the number of covariates has been gradually decreased to eliminate insignificant covariates.
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..
Haspelsystemet Camcoil 1500
Our employer Camatec Industriteknik AB gave us the assignments to increase theirs range of versions on Camcoil that is their own patent product. Camcoil is a capstan system that is used when steel band fabricated. Exist for example in production lines their steel band should be annealed. Our goal with this work is to come up with a completed production basis on a Camcoil for heavy industry. The basis should contain calculations, 3D-constructions, drawings and cost proposal on manufacturing and detail purchase.Demands on this project:1.
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.
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..