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1242 Uppsatser om Tire models - Sida 1 av 83
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.
Influence of providing objects to piglets before and after weaning on behaviour and weight gain
Barren rearing environment and early weaning of piglets can lead to a high level of distress, behavioural disturbances and reduction in weight gain. The main aim of this thesis was to study the effects of potential enrichment objects on piglet?s behaviour and weight gain during the pre- and post-weaning period. The second aim was to examine what type of object stimulated the highest frequency of interaction.
The study was carried out at the Swedish Livestock Research Centre in Lövsta where a batch of litters from 10 first-parity Yorkshire sows were used.
Utvärdering av metoder och modeller för att simulera växlingskomfort i entreprenadfordon
Good comfort for the driver of a construction machine is crucial. Gearshift comfort is an important part of the total comfort. Volvo Construction Equipment Components has a simulation environment of the powertrain, SimPow, which is implemented in Matlab/Simulink. SimPow is mostly used for simulation of control strategies and performance. In order to be able to study gearshifting comfort, Volvo has an interest in developing new models for SimPow.
Verktyg för hjulbyte
Purpose of the thesis is to construct a tool for car wheel change. Car wheels can be heavy and hard to handle and therefore the company Movomech intends to develop a tool that makes wheel change easier. Movomech does not have any similar product and because of this the work was condition less.The intended users of the product is tire workshops and there for the work began with investigation of these. The reason of the investigation was to see how wheel change is done and how tire workshops are planed. The tire workshops? crew?s opinions were also considered and above all one important conclusion was made.
Nedbrytning av vägar: Jämförelse mellan axlar med singel- respektive tvillingmontage
When designing roads it?s important to knowwhat loads will bedriven on it. The axles on heavy vehicles can either have super single tires ordual tires which, according to studies, damage the roads differently. The SwedishTransport Administration is developing an understanding for the character ofthese different kinds of axle and tire types on the loads induced on Swedishroads. In this thesis a field study was conducted to determine the distributionbetween axles with super single tires and axles with dual tires on heavy vehicles.A highway, a country road and a national road were investigated during thestudy.
Utvärdering av CTI på virkesfordon : ? CTI-projekt Holmen Skog/Örnfrakt 2005-2006
The low bearing capacity of roads during the spring thaw and periods in the autumn leads every year to increases costs for Holmen Skog. To reduce costs and increase accessibility
Holmen Skog decided to install and test a CTI-system. Central tire inflation (CTI) is a system that makes it possible to monitor and vary a vehicle?s tire inflation pressures from the cabin, while the vehicle is in motion. When tire pressures are reduced, the area of the contact surface between the tire and the road increases, thus reducing the ground pressure.
The purpose of this study was to evaluate the CTI-equipped vehicle and analyze if the CTI technology is economical defensible during the thaw 2005.
Konstruktion av truckmonterad hjulhanterare
GBD-Storage Systems is a company that provides the industries with products for efficient storage.The company produces pallet racks and accessories like cassettes and extending units. The companyhas also supplied tire racks for a number of tire companies. The company's CEO Gunnar Berglund hasfor some time had an idea to improve the working situation of the workers on tire firms by allowingthe wheels to be handled by a counterbalance truck. The current situation poses numerous heavy liftswhen the tires are handled and therefore is hurting the workers.This thesis has been aiming at helping the GBD-Storage Systems by developing a concept of howan accessory to counterbalanced trucks can be designed to cope with the wheels. This concept willthen be produced as prototype by the company.
Transferfunktionsmodeller modellering och prognoser av Sjötransportindex
We have by Statistics Sweden (SCB) been given the task of using different dynamic regression models in order to forecast service price index for sea transport. The aim is to see whether these models provide better forecasts than those previously used. This essay aim to identify, estimate and evaluate the selected prediction models. Through our data material we were given access to 28 sightings of sea transport index during the period of 2004 q1 to 2010 q4. We have chosen to evaluate three different transfer function models, one ARIMA model and one naive forecasting model. The input variables we decided to test in our transfer function models were the price of petroleum products, the port activity in Swedish ports and the lending rate of Swedish Central bank. The results of our study suggest that transfer function models generally provide better models than the ARIMA model and the naive forecast model.
Va?gen till ett va?rdeskapande HR : En kvalitativ studie av personalarbete i en offentlig organisation
The field of work and employment is constantly undergoing changes. In order to help organizations to adjust to new conditions, different models for organizing have been developed. Many of these models are spread worldwide, due to the need for organizations to meet demands of flexibility and efficiency. In this study, a small number of models, which contains solutions of how to organize work in Human Resources, have been selected. The author and scientist Dave Ulrich, who has had a large influence on the development of the work in Human Resources, originally founded these models.The aim of this study was to examine how these models were functioning, in reference to the different departments of Human Resources labor within the township of Uppsala.
Dominerande affärsmodeller inom området informationssäkerhet
Computers together with Internet have been growing enormously, during the last decade and the area of information technology has been growing in the same speed. As long as the surrounding environment evolves, the business models must within the IT-area, keep the same pace. So, how do business corporations handle this change to attract customers? How do the dominant business models look like? In many cases, they are apparently much the same. But what differences can we see and what areas can be improved? We have showed that the IT area isn?t just one, it consist of several segments.
Börsvärdering av bioteknologiska forskningsbolag
Background: The valuation of Biotechnology companies is difficult in many ways. Patent and human capital are hard to value and also there is a great uncertainty about the success of the compaines research programs. Are traditional valuation models really useful when it comes to research companies or do they result in false values of the companies? Purpose: To study what values different valuation models gives biotechnology companies and how they correspond to the market value. Method:We have studied financial litterature och found the most common used models today.
Dominerande affärsmodeller inom området informationssäkerhet
Computers together with Internet have been growing enormously, during the last
decade and the area of information technology has been growing in the same
speed. As long as the surrounding environment evolves, the business models must
within the IT-area, keep the same pace. So, how do business corporations handle
this change to attract customers? How do the dominant business models look
like? In many cases, they are apparently much the same. But what differences
can we see and what areas can be improved?
We have showed that the IT area isn?t just one, it consist of several segments.
Utveckling av en dynamisk Simuleringsmodell av en skotare
The predominant forestry harvesting method is based on the harvester-forwarder method, theharvester folds, branches and cuts trees, and sorts the logs into piles, while a forwarder transportsthe logs to a landing area.This master thesis work is about realization of a dynamic forwarder simulation model, and itspurpose is to provide an integrated forwarder simulation model in MATLAB/SimMechanicswhere the forwarder is based on a concept using pendulum arms to connect wheels and chassis.Active suspension control is developed and implemented into the simulation model, and finallycompared in simulation with passive suspension.In a first step, an integrated forwarder simulation model is developed, containing a simplifiedforwarder model, a tire-to-ground interaction model and a test track model. The simplifiedforwarder model is based a rigid multi-body system with a spring-damper suspension of thependulum arms. The tire-to-ground interaction model calculates the reaction forces, friction fromthe ground and applies the propulsion force. The test track model is a simplified version of thereal test track in Skogforsk. The propulsion wheel torque control is used to regulate theforwarder speed.
Finansiella värderingsmodeller : En empirisk studie
This study tests two financial valuation models empirically by valuing three stocks from three industries, with the purpose of studying how well valuation models work empirically and to make a forecast. The models which will be tested are residual income valuation and discounted cash flow. Nine stocks will be picked strategically from the Swedish stock market and additional analysis will follow in the analysis chapter.Based on analysis and valuation, the commodities industry has decent valuation as the healthcare industry is undervalued thanks to the high valuation of AZN. The energy industry has low value due to the capital intensive nature of the industry. When it comes to the models and their practical implementation, DCF has been the most problematic to apply empirically whereas RIV was better but it still shows extreme values, which teaches the student the clear difference between theory and empiri..
Validering av vattenkraftmodeller i ARISTO
This master thesis was made to validate hydropower models of a turbine governor,Kaplan turbine and a Francis turbine in the power system simulator ARISTO atSvenska Kraftnät. The validation was made in three steps. The first step was to makesure the models was implement correctly in the simulator. The second was tocompare the simulation results from the Kaplan turbine model to data from a realhydropower plant. The comparison was made to see how the models could generatesimulation result that was similar to the reference power station.