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4324 Uppsatser om Calculations model - Sida 13 av 289

Utveckling av en Multi-Zonsmodell för NOx Bildning i Diesel Motorer

This thesis work is the last part of the Master of Science education inmechanical engineering at KTH, Stockholm.The aim of this project was the development of a Multi-zone modelfor NOxformation in Diesel engines. Because of the stringent emissionlegislations, great effort is made to decrease the fuel consumption and theharmful emissions of internal combustion engines. Computer simulationsplay a decisive role in this context because they substitute the expensiveand time-consuming laboratory tests.The model is based on a multi-zone approach and uses the wellknownExtended Zeldovich Mechanism which gives a relation to calculatethe NO formation rate using the concentration of different gas speciesinvolved in the process.All the most important phenomena involved in the Diesel combustionhave been modelled. A special attention is then paid to the equilibriumconcentration calculation; this is a significant part of the model whichstrongly influences the following steps.A Simulink model has also been developed. This second version isbased on the previous model and it is made especially to allow theconnection with other external softwares, GT-power in this case.

Investerargrupper : En studie utifrån Wärneryds investerarmodell

Listed corporations achieve effectiveness through segmentation of investors. Categorization of like- minded investors diminishes goal incongruence. This thesis aim to examine an Investor models accuracy, provided by a Professor Emeritus in Economic Psychology in 2001. This model segments investors as active, passive, speculative and naive investors. This thesis has a demarcation to private investors on the Swedish stock market. It has a deductive and qualitative approach as the purpose is to study the Investor model.

Environment simulation of track-based systems

Simulation means running a model of a system with suitable input and observing the corresponding output. Real-time environment simulation is a special kind of simulation used to simulate a control system's environment in real-time. This is done to test the control system before it is used in its real environment. In this project, computer simulation of a certain kind of environments, called track-based systems, is studied and a general model for track-based systems is developed. In this model, track layouts are represented by graphs, which is a flexible and extensible representation and a method for visualizing these layouts is presented.

Uppdatering av båtnadskalkyl med hänsyn till nya faktorer :

Sweden have 419 000 km road in the country and about half of these roads is forestroads. The forest road net most important mission is to make it possible to deliver wood from the forest to the industries. With a raw material that is spread over a large area the road network is important. Each year has the forest road network been extended with about 1 700 km new roads. To decide if a new road is to be built different forest road cost estimation models has been used.

Rimbo våtmark : en förstudie på förväntad kväveavskiljning och lämplig växtlighet

This study was made as a part of a feasibility study on a polishing wetland at Rimbo wastewater plant (wwp) in Norrtälje municipality. The wwp had to decrease the nitrogen discharge to reach the limit 15 mg tot-N/l. The nitrogen in the outlet was mainly in the form of nitrate, hence the wetland mainly ought to support denitrification. The proposed area for the wetland was situated right next to the wwp and was already in the municipalitys posession. One aim of this study was to examine what spieces of plants needed to achieve highest possible denitrification.

"Prata högre! Jag hör inte vad du säger" : En kvalitativ studie om elevers och pedagogers upplevelser av Södertäljes nya skolmodell

"Speak up! I can?t hear you"This qualitative study is built on an investigation of a newly instated model that is used when building or renovating schools. The principles of the model are based on building schools with an open plan design where the walls are made of glass and the classrooms are not shut closed by walls, instead the classrooms are completely open except from screens that are used to indicate the ambit of the rooms. This model has been well debated and that is the reason why we chose to do this study.The purpose of this study is to find out how students and teachers experience this model. To do this we have done interviews and observations.

Hjälpkraftsystem med två lågspänningsnivåer

Because of increasing demand of power on Malmbanan the capacity of the existing wires which supply the trains must be increased. This increases the stress on the existing poles and for this reason the system for supplying the loads along the railway is to be removed from the poles and be replaced by some other system. This thesis is a study on a two-level low voltage (1 kV and 0.4 kV) electrical system with the aim to investigate if it can be an alternative to the system used today taking into account the voltages, fault currents and costs.In this thesis the following tasks have been performed:? Gathering of data? Description of basic theory? Loadow and fault current calculations of the system with MATLAB? Life Cycle Cost estimate of the system? Analysis and conclusions from the resultsThe results show that the new system can be an alternative to replace today's system. The simulations and calculations show that the voltage drop is at an acceptable level and that the fault currents are large enough to supply a safe disconnection if a fault occurs at the far end of the system..

Allsvensk fotbollssponsring

Purpose: The purpose of this thesis is to examine the ERK model's relevance, validity and potential need of development to better reflect how it looks today (2013). Method: The study is conducted through three surveys; the first two were face interviews with companies that sponsor Swedish soccer teams and the third study was conducted with a questionnaire to supporters outside a soccer stadium. Results: A model that would better reflect the reality of today (2013) could contain company pride, chairman?s whim, exposure, relationships and associations..

Utveckling och utvördering av statistiska metoder för att öka träffsäkerheten hos lokala vindprognoser

Wind is used as an energy source all over the world. To be able to use this effectively, there is a need for as good forecasts and forecast models as possible. One of these models is Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS®) that is used to calculate short time forecasts. This model is used here to calculate wind speeds at two different areas in Västra Götaland, Bengtsfors and Vänersborg. There are also wind measurements with SODAR stations for these areas.

Optimalt råvarulager för biobränsleföretaget :

This report was written as a final thesis within the Department of forest economics at the Swedish University of Agricultural Sciences as a completion of the M.SC Forestry programme. The aim of this study was to create a model that, with respect to given stock levels, temperature, fuel usage and fuel price, would identify the optimal levels for purchase of bio fuels, optimal levels of incineration of bio fuels and the sum of the present values of all costs. The model would be applicable for a larger district heating plant. Data regarding temperature were received from SMHI. Information considering fuel prices was taken from the Swedish Forest Agency and the facts about fuel usage were collected from a large district heating plant, located in the southwest of Sweden. For the temperature, a sinus curve was adapted to describe the temperature over a year.

MED ARBETET SOM LIVSPARTNER: En studie i engagemang till arbetet med hjälp av the Investment Model

I ett samhälle där relationer, även sådana av icke romantisk karaktär, har en central roll imänniskors liv är det viktigt att försöka förstå vad som ligger till grund för individers engagemangi relationer. The Investment Model säger att engagemang i relationer ökar då individerupplever ökade belöningar, minskade kostnader, färre attraktiva alternativ samt att deinvesterat mycket i relationen. I föreliggande tvärsnittsstudie undersöktes 61 grundskolelärarei Göteborgs Stad, med hjälp av the Investment Model, angående upplevt engagemang tillsitt arbete via ett frågeformulär. Studien visade att grundskolelärare med längre anställningstidupplever att de investerat mer i sitt arbete än vad de med kortare anställningstid angav..

Vi tar tempen på ert CO2-utsläpp! : en studie av hållbarhetsredovisningars användbarhet

The environment has become an important part in people´s lives, and in today´s society stakeholders demands have increased upon companies when it comes to sustainability reports. How these sustainability reports are designed depends on whom it?s for, laws and regulations, and the companies own norms and values. The purpose of sustainability reports is to measure, monitor and compare a company´s enviromental impact. It?s not only about integrating economics, but also enviromental and social standards together to get both financial and competitive advantages.Sustainable Value method is a new model and is the first real method that can be used to evaluate a company´s resources, both financial, social and enviromental to a sustainable value.This model is used to compare the resource efficiency between companies.In this thesis, a documentary study with an experimental approach has been made.Sustainability reports from six selected companies (in the engineering and forestry sector) have been investigated with respect to their accounting for carbon dioxide, and an experiment using the method ?Sustainable Value Approach? was subsequently performed.

Modell för fördelning av kostnader i lager

Distrilux International AB, a company within the Electrolux-group, works among other things with storing of products from other companies in the Electrolux-group. This rapport contains a cost analysis of the two Distrilux warehouses in Motala and Mariestad. The company offers five services in these warehouses, in-loading of products from a local factory and from external factories, storing, out-loading of products to Sweden (domestic) and for export. Since there has been some hesitation of the accuracy of the price-model of today, a master's thesis has been advertised. The purpose of the thesis has been to investigate the agreement of the price-model of today and the apportionment of the costing in warehouses.The main problem is to determine which activities is to be considered important in the price-model.

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.

REDOGÖRELSE FÖR SPRICKARMERING FÖR KONSEKVENT DRAGNA BETONGPLATTOR PÅ MARK : Analys av skillnader mellan BBK 04 och Eurokod 2 med tillämpning av svenskt och danskt nationellt annex

In this diploma work the approach of determining the required amount of reinforcement in slabs exposed to pure tension is processed, on behalf of Ramböll Uppsala. It is a well-known problem in the industry that there are uncertainties in the determining of the amount of crack reinforcement, especially for structures exposed to pure tension. Cracking caused during the time of dehydration in concrete slabs is the most common defect according to statistics made by CBI[1], which provides numbers as high as 35 % of all the defects caused on slabs are generated by cracks. Comparisons between Sweden's former national standard BBK 04, Building Regulations for concrete structures due to restrained forces of shrinkage, and the current European standard Eurocode 2 are carried out through theoretical studies and concludes with several examples of calculations. Rigorous calculations of both standards, BBK 04 and Eurocode 2 with application of the national annex in Sweden and Denmark are performed.

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