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4083 Uppsatser om Modified Jones model - Sida 4 av 273

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.

Hydraulisk och termisk grundvattenmodellering av ett geoenergilager i Stockholmsåsen

Geothermal energy can be extracted from an aquifer, where the groundwater is used as heatexchange medium while heat and cold are stored in the surrounding material in the aquiferand to some extent in the groundwater. Application of aquifer storage for the use ofgeothermal energy is mainly used in large scale facilities and is limited to sites with suitableaquifers in the form of ridges, sandstone and limestone aquifers.Löwenströmska hospital in the municipality of Upplands Väsby, north of Stockholm, islocated nearby the northern part of the Stockholm esker. This means that it can be profitableand environmentally beneficial for the hospital to examine the possibilities of aquifer storagein the esker material next to its property.The purpose of this master thesis has been to investigate if geothermal energy storage with aseasonal storage of heat and cold can be applied within Löwenströmska hospital?s propertyarea using groundwater modeling. A hydraulic groundwater model was constructed inMODFLOW based on a simplified conceptual model of the groundwater system.

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.

Däck-mark Interaktion hos skogsmaskiner

The most predominant method for forest harvesting in Sweden is the cut-to-length method based on two-machines, a harvester that fells trees and cut them in a predefined length, and a forwarder which transports logs to a landing area for further transport to a processing facility. New machine solutions have to be much gentler to the ground than today?s machines. To be able to develop a forestry machine that preserves the terrain requires a proper understanding of the interaction between tire and soil.The goal of the project is to contribute to the existing knowledge of forest machine tire-soil interaction and to develop a tire-soil model that enables dynamic simulations of forest machines operating in rough terrain. The modeling has especially been focused on the interaction between tires and soft ground.A comparison of theoretical data of different WES-based terrain interaction models and a comparison test data from a full scale field test is presented.

Identifiering av områden med risk för fosforförluster genom ytavrinning : metodutveckling med GIS

The eutrophication of lakes and seas with the algal bloom and deficiency inoxygen that follow, has been given priority by the Swedish government as oneof 16 environmental objectives. The purpose of this project was to develop a toolbased on a simple model, limited amount of data and geographic informationsystem (GIS) to identify areas with risk for phosphorus losses due to surfacerunoff. This tool can act as a decision support to decide where appropriatemeasures should be applied with the aim of reducing phosphorus losses and bythat the eutrophication.The method that has been used is a combination of two models, one calculatingthe potential erosion while the other one identifies areas of erosion (net erosion)or deposition. This ability is of great importance because potential erosionshould be calculated on areas with net erosion. Areas with high potential erosionhave an increased risk for phosphorus losses due to surface runoff.The potential erosion was calculated based on factors which describe how topography(LS), land use (C), soil type (K) and precipitation (R) effect the erosion.All of them have been modified to a greater or lesser extent.

Is less more?

Back in the 1950s Marilyn Monroe and her hourglass shaped body was the aesthetic ideal for how models were to look like. Nowadays, the tide has turned. Research has shown that female models are becoming increasingly taller, narrower and straighter. This trend has occurred despite the fact that both men and women (still) prefer medium sized women with curvy bodies. This essay examines if this trend can be justified from a marketer's perspective.

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.

Beräkningsmodell för massbalanser för Slottshagens reningsverk

In the next few years the pollutants loading at the Slottshagen wastewater treatment plant in Norrköping is going to increase due to the reason that one of the waste water treatment plant in the district will be shut down.A survey of how these different pollutants are divided in the treatment process is therefore necessary for mapping out both the loading and treatment efficiency.This can be achieved by studying mass balances.Mass balances were carried out for the water treatment process for the mechanical/chemical,biological and the chemical stage.The mass balance studies show that the treatment efficiency was very good. However in order for the mass balances to be quite consistent and to ensure complete coverage of results and conclusions i.e. more reliable results, sludge samples should be collected and taken at different times per day and the influent rate should be investigated.In this work mass balance has been set up in order to illustrate and identify the factors that should be considered and taken care of for further estimation using mass balances in the future. Furthermore this survey results in a calculating model for the mass balances at thisplant.This calculating model is used as a tool to facilitate future calculations for mass balances for the water treatment process at Slottshagens wastewater treatment plant.Moreover it provides a basis for carrying out further estimation of the treatment process in the near future.In this project the importance of some operating parameters was also taken in consideration.This calculating model can be modified so that calculations of such operating parameters i.e. sludge loading and sludge age can be easily performed.Such information can be used further to evaluate different operation alternative in order to ensure an optimal use of the treatment process with in the plant..

?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.

Hur kan den interaktiva skrivtavlan fungera som ett stöd i matematiklärandet i F-3?

The purpose of this thesis is to examine which role public libraries play or could play within bibliotherapy. The study is based on qualitative interviews with five librarians who, in one way or another have experienced bibliotherapy activities. Further, we have interviewed two treatment assistants and one counsellor, who have cooperated with the librarians, to get their view. We have used the following research questions: Which bibliotherapeutic activities, if any, are pursued in public libraries in Sweden, and how do they look upon bibliotherapy? What role do public libraries play/could play within bibliotherapy? Ever since the term bibliotherapy was coined in the beginning of the twentieth century, the definition has been under debate. We have identified four main subjects of discussion.

Volvo Cars servicestrategi för eftermarknaden

Demands on businesses are constantly increasing and the competition in the market-place is becoming ever tougher. To gain the long-term confidence of customers, not only the best businesses, but also the best supply chains are required.Volvo Cars is experiencing a changing competitive situation and their retailers are having trouble stocking the right spare parts. Shorter product life cycles and the growth of Volvo?s product program result in an increase in the number of spare parts to be stocked. In order to adapt to market trends and meet customer demands, Volvo has developed the LDC model, establishing a number of regional warehouses in strategic locations in Sweden, de-signed to supply spare parts to the regions? retailers through so-called Vendor-Managed In-ventory (VMI).The purpose of the study is to examine Volvo personbilar Sverige?s (VPS) motivation for a modified customer-service strategy through LDC.

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..

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