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2427 Uppsatser om Population models - Sida 14 av 162
Parametriserad modell av motorprototyp med Solidworks
The purpose of this thesis has been to build a parameterized model of a prototype motor in the program Solidworks, to use in future optimization of aspects of effectiveness and weight. The result were two models. The first model were one minor part of the whole design in 2D, to be able to optimize and study the minor part with a faster loss simulation. The second model was the whole design in 3D. The whole model were done with the three programs Solidworks, Comsol and Matlab.
Rekursiv greyboxidentifiering av drivsystem i industrirobot.
In modern industrial robots the components in the transmission contain nonlinearities. These nonlinearities need to be to estimated either for better control or to use the parameters for diagnosis of the system. There is a lot of work done within system identification and mainly within the field of iterative parameter estimation.This thesis considers recursive grey-box identification for a nonlinear model of the transmission in an industrial robot. The nonlinearities that are identified are friction, spring stiffnes, hysteresis and backlash. These nonlinearities are a part of the models that are presented in this thesis.
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..
attraktrivitet och regionplanering : Hur ska osby kunna ha en positiv ekonomisk tillväxt och befolkningsutveckling i region skåne?
AbstractAttractiveness may be defined by a variety of factors but you should see it in the public planning as it is to have a positive population growth and economic growth, through working with communications, service, housing, to name a few. This is done primarily through direct projects both within the municipality and through various partnerships between local and regional level. The progress we have seen in recent years has gone more towards a clear shell level, particularly a regional level where these have had a much greater freedom with clear geographical boundaries in between each other. Within these regions there are also clear regional groupings that have common interests and competing between each other. In my thesis, we have been distinguished including three levels of scale levels.
Energisystem med utnyttjande av restprodukter för gödsling av Salixodling för energiproduktion : studier av kretslopprojektet i Enköping och dess applicering på en kommun i Ryssland.
The purpose of this work is to study a circulation project in Enköping municipality, where the society?s rest products are used to make beneficial products. In Enköping the rest products from waste treatment plants and private sewers are used to fertilize and irrigate Salix plantations that later are harvested and burned at the local combined heating and power plant, ENA Energy AB, to produce electricity and heat. Possibilities to apply this kind of project ona municipality in Russia are also explored.Guryevsk municipality in Kaliningrad region was chosen since there is a need to improve energy systems and reduce emissions to water and air. This municipality strives to become environmentally friendly.
Samband mellan trafikolyckor och väggeometri. En analys av kopplade olycks- och vägdata för större vägar i Region Väst
Today more effective computer programs are in use, regarding design of geotechnicalconstructions. There is a risk that the theoretical background of the computerprograms, its limitations and the signification of the choice of soil parameter isforgotten when the computer programs become more user-friendly.This Master thesis deals with simulation and analysis regarding three computerprograms, FEM-design, with the addition Raft, Plaxis and BE-slab. Comparisons aremade for settlement and maximum moment in a concrete-plate. FEM-design is a threedimensional FEM-program, foremost created for design engineers. Plaxis is a twodimensional FEM-program, intended for geotechnical engineers while BE-Slab is aBoundary elements program in two dimensions that is mainly used by designengineers.
Trafiksäkra vägar genom god vägutformning baserat på kunskap om det mänskliga beteendet - en utvärdering av metoden IST-Checklist 2005
Today more effective computer programs are in use, regarding design of geotechnicalconstructions. There is a risk that the theoretical background of the computerprograms, its limitations and the signification of the choice of soil parameter isforgotten when the computer programs become more user-friendly.This Master thesis deals with simulation and analysis regarding three computerprograms, FEM-design, with the addition Raft, Plaxis and BE-slab. Comparisons aremade for settlement and maximum moment in a concrete-plate. FEM-design is a threedimensional FEM-program, foremost created for design engineers. Plaxis is a twodimensional FEM-program, intended for geotechnical engineers while BE-Slab is aBoundary elements program in two dimensions that is mainly used by designengineers.
Buss eller spårvagn? Framtida kollektivtrafikförsörjning av området mellan Kungssten, Frölunda torg och Saltholmen i Göteborg
Today more effective computer programs are in use, regarding design of geotechnicalconstructions. There is a risk that the theoretical background of the computerprograms, its limitations and the signification of the choice of soil parameter isforgotten when the computer programs become more user-friendly.This Master thesis deals with simulation and analysis regarding three computerprograms, FEM-design, with the addition Raft, Plaxis and BE-slab. Comparisons aremade for settlement and maximum moment in a concrete-plate. FEM-design is a threedimensional FEM-program, foremost created for design engineers. Plaxis is a twodimensional FEM-program, intended for geotechnical engineers while BE-Slab is aBoundary elements program in two dimensions that is mainly used by designengineers.
Föroreningstransport i grundvatten : En modelljämförelse
This thesis compares different methods for risk assessment of a creosote contaminated site in Vansbro, Dalarna. In a complementary study the importance of using representative data for calibration and validation of stationary groundwater models is discussed. The time dependency between surface water levels and groundwater levels on the site in Vansbro is evaluated by step response analysis. The results show that the groundwater levels reflect only long-term variation in the surface water levels. Hence the use of such long-term means for calibration and validation of the stationary groundwater models is the only theoretically defendable alternative.As a first step in the comparison of risk assessment methods the degree of contamination is evaluated on the basis of generic guideline values for contaminated soils, developed by the Swedish Environmental Protection Agency.
Användbarheten av två modeller i två olika företag, en studie av lean production : Fallstudier vid SKF Couplings systems och AQ Parkoprint
This study is about to see whether the two models representing the strategies of lean production is to use and apply in different companies. The models are structured in two different ways in which one of them is checking the softer elements of lean production in the form of leadership and strategies. This model is called Lesat and is based on interviewquestions. The second model, called "learning to see" is about identifying flows. This, together shall then give an idea of how mature companies are when it comes to a whole in the concept of lean production, and susceptibility to use these models to their respective companies. The study is conducted in two companies, SKF couplings systems and AQ parkoprint.
Value-at-Risk : Historisk simulering som konkurrenskraftig beräkningsmodell
Value-at-Risk (VaR) is among financial institutions a commonly used tool for measuring market risk. Several methods to calculate VaR exists and different implementations often results in different VaR forecasts. An interesting implementation is historical simulation, and the purpose of this thesis is to examine whether historical simulation with dynamic volatility updating is useful as a model to calculate VaR and how this differs in regard to type of asset or instrument. To carry out the investigation six different models are implemented, which then are tested for statistical accuracy through Christoffersens test. We find that incorporation of volatility updating into the historical simulation method in many cases improves the model.
Linné hemvård : En grafisk profil till ett nystartat företag
The purpose of this work is to develop and test a design process where quick decisions and model building has a prominent role. The goal is to develop a number of products and build prototypes to be shown during the Carl Malmsten Furniture Studies spring exhibition 2012. I?m also writing a report describing my work.To reach my goal I have each day during the first phase conducted a short research and found a concept based on that days name day. Then I have continued in the workshop and worked with three-dimensional models.
Informationsfrihet och IT-användning i demokratifrämjande syfte
The potential of information technology as a means to invigorate democratic practise is constantly under discussion. Regardless of the differing opinions as to the most suitable way to utilise IT, there are certain democratic core values that have to be considered. One of these is freedom of information, defined by us as the right of every citizen to seek, obtain and express information. The aim of this study is to explore whether the use of IT as a means to enhance democracy can strengthen the citizens right to freedom of information. As an instrument for analysis we use an article by Jan van Dijk, professor of communication science.
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.
Analys av hemområdesstorlek hos mellansvenska vildsvin (Sus scrofa scrofa)
The wild boar population grows rapidly in number in Sweden, and it has been predicted that the annual number of shot wild boar will soon exceed the cull of moose. According to estimates, the Swedish population encompassed some 150 000 individuals in 2010. The mean annual harvest has increased by 30% since 1990, indicating that the wild boar is a species we must learn to manage sustainably. A successful management of the boars aims for a population in balance with agriculture and traffic, and also provides good hunting opportunities. For this to be possible, understandings of several aspects of the ecology of wild boar is needed.
The sows in this study had an average homerange of 707 hectares during summer, and 659 hectares in winter.