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3955 Uppsatser om Error correction model - Sida 6 av 264

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.

Regressionsmodellering av dynamiska råemissioner från statiska mätningar

By using steady-state measurements for predicting emissions under a dynamic drive cycle wouldsave a lot of time and money for the exhaust aftertreatment specialists at Volvo cars. The idea forthis thesis has been to investigate if statistical regression models can be used with good accuracy.Questions included are for example if common operating variables such as engine speed, air-fuelratio etc. is sufficient to predict engine-out emissions over the engine operating range with goodaccuracy. Focus was set on the modelling of warm engine, but also the more complex engineheat-up phase was investigated since it is a great contributor to total emissions. While NOxcouldnot be measured because of malfunctioning measurement equipment, only HC, CO andtemperature at inlet of first catalytic converter has been modelled.

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.

A Strategic Decision-Making Model for Supply Chain - A Void to be Filled

Many researchers emphasize the increasing strategic importance of supply chain management, but there is still a lack of concrete guidance for managers faced with strategic decisions in supply chain. Within decision-making theories, the rational decision-making model is the most commonly used. This because of its suitable foundation, enabling a structure to the complex decision process. The rational decision-making model is today not developed to include the aspects of strategic decision-making made in supply chain. The purpose of this research is to adjust a structured rational decision-making model, making it applicable for strategic decision-making in supply chain.

Dynamisk modellering av VSC-HVDC : En statisk och dynamisk modelldesign o?ver VSC-HVDC fo?r implementering i ARISTO

This thesis treats the subject of a complete steady state and dynamic model of the VSC-HVDC covering both the AC and DC system-side of the converter. The topology of the model is recreated after the scheduled transmission line in the south of Sweden, called SydVa?stla?nken. The topology covers both a simple two terminal connection as well as a multi-terminal one. This model is to be implemented in the power system simulation program ARISTO.

Yrkesrelevant Gymnasiearbete på El- och Energiprogrammet

The purpose of this development project is to create a model for working with a high school project in Electrical and Energy Program. It should be conducted in a form like companies do according to the goals from The Swedish National Agency for Education. In order to fully perform this we use the concept of Young Entrepreneurship. The model is created according to the new conditions from The National Electrical Safety Board. There is now an exception saying that a student during education is released from the demand of employment that is the normal procedure where you are under supervision from a certified electrician. During the project there has been theoretical and practical examinations in order to clear out the advantages and disadvantages using this model, but also to examine whether it is useful in the future and to what extent it can be used. The result indicates that the model is useful and fulfills the goals from The Swedish National Agency for Education but that the model has its limitations and difficulties.

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.

Beräkning av energianvändning i svenska småhus

An energy calculation model for Swedish houses   that is fast, flexible and user-friendly has been developed within the   framework of this thesis.  The model   also provides a set of actions which may be investigated in the model based   on savings and payback period. Energy use in a house depends on the technical   conditions, such as building envelope and heating systems, which outdoor   climate the house is exposed to and who lives in the house. Energy use for a   house can be divided into heating, hot water and household electricity. There   are several methods to calculate the energy use of a house. This report   summarizes the methods that may be suitable for a fast and user-friendly   calculation model.

Marknadens riskpremie ex-ante på Stockholmsbörsen

Resultaten visar på att abnormal earnings model är en mertillförlitlig modell i förhållande till dividend growth model. Dettafrämst då abnormal earnings model grundar sig på mer tillgängliginformation samt att tillväxträntan i dividend growth model harkonstaterats vara orealistiskt hög. Analytikers prognoser tenderaratt vara optimistiska i början av undersökningsperioden 2000-2002. Perioden 2003-2007 präglas mer av pessimistiskavinstprognoser. Marknadens riskpremie fluktuerar mindre underperioden 2005-2007, vilket kan förklaras utav införandet av IFRSår 2005..

Den militära nyttan med ett digitalt eldledningsstödssystem vid precisionbekämpning

Då dagens konflikter ofta utspelar sig mitt ibland civilbefolkningen och där aktörerna kan utgöras av allt från miliser till kriminella gäng ställs det nya krav på de militära förmågorna för att kunna agera i dessa komplexa miljöer. En generell trend för dagens artilleriförband är att de används till att verka mot mindre målgrupper utgörandes av två till fyra personer. Erfarenheter från konflikter i likhet med de i Irak och Afghanistan har visat på vikten av tillgång till precisionsbekämpning med indirekt eld för att undvika förluster bland de civila. En förutsättning för att kunna genomföra precisionbekämpning är att målets position kan lägesbestämmas med en mycket hög noggrannhet.Med hjälp av ett digitalt eldledningsstödssystem innehållandes en tredimensionell digital karta kopplat till EOI:et kan positionsfel i måluttaget i en urban miljö reduceras till under metern. .

Värdeförändring på butiksfastigheter och makroekonomiska variabler - en ekonometrisk studie av samvariation

The purpose of this Bachelor thesis in Economics at Lund University is to try to establish the correlation between the value change of retail real estate buildings in Sweden and macro economic variables. The principal method is the multiple regression model and it is used to estimate the basic model. The basic model is enhanced by estimating some 30 models and the result is two good models. The difference between the basic model and the two better models are small but important. In the lagged basic model, the same variables are used as in the basic model but with different time lags.

Prestandabaserad design genomkonceptuell energianalys : Performance-based design through conceptual energy analysis

This degree project aims to investigate the potential and possibilities for conceptual energyanalyses in the early stages of the design process. Many key decisions are made in theearly stages of a project regarding the shape and orientation of the building. Conceptualenergy analyses can provide the architects with insight regarding different design option?srelative energy performance.As the demands for more sustainable buildings increases, so does the need for earlyenergy analyses. Performing analyses in the early stage requires many assumptions andguesswork which could lead to a large margin of error.The offering from Autodesk is a module in Revit Architecture/MEP and the stand aloneprogram Project Vasari (under development).

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