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713 Uppsatser om Dynamic simulations - Sida 11 av 48
Utvärdering och implementering av automatiska farthållare i fordonssimulator
Vehicle simulators are becoming more common in vehicle industries. Company earns lot of money on simulations instead of real tests. Real tests are necessary but not made so extensively as before.In this thesis the building of an vehice simulator will be described and a comparison between three different cruise controls. The three cruise controls are PI-regulator, a regulator who regulates after positions in the terrain and a MPC-regulator. The reason for choosing this three is to see the difference between simple regulation and more complex regulation with respect to fuel consumption, travel time and complexity.The vehicle simulator is made in Matlab/Simulink, Visual Studio and Open Scene Graph.
Modeller för studier av ursprungsmärkt el
The EU has decided that it should be possible for consumers to get information about the origin of the electricity they buy. Therefore, there is a need to examine different systems for electricity disclosure. In this thesis two ways of disclosure have been studied:? Certificate system. A certificate system involves two parallel markets, one for trading electrical energy and one for trading certificates of origin.? Separated Markets.
Balanced Scorecard identifieringens dolda dilemma
The use of balanced scorecards have spread explosively throughout the world during the last decade. This management tool have become very common in a vide spread variety of organisations on all continents. Many balanced scorecard fails though and scorecard theorists often blame the identification- and implementation process as they claim that these lay the foundation for the use of the tool. As my literature study shows, academic research on the area is rare. Particularly the effect on the implementation process from organisational dynamics and organisational structures needs further research.
Åsktransienter och överspänningar : En spänningsfylld simulering av elkraftsystemet vid Forsmark 3
A power system will inevitably be subjected to transient overvoltages, most often produced by switching operations and lightning strikes. These transient overvoltages may harm sensitive equipment without sufficient protection, but it is not an easy task to predict what transients may occur or how they affect the system. A fault occurred in a low voltage system at Forsmark 2012 and overvoltages from lightning were concluded as the probable cause. The three aims with this thesis are to develop and test a model of the power system at Forsmark 3, analyse the transient behaviour of the system when subjected to lightning surges and identify critical parameters, and lastly to provide a tool for investigating the protection of the system. The modelling and simulations were performed in the freely available simulation program LT Spice.
Exportera mera! : faktorer som påverkar en framgångsrik export av svenska livsmedel
Exporten har en betydande roll i dagens samhälle och verklig påverkan på landsbygden och dess framtida möjligheter till överlevnad i ett urbaniserande och teknikfokuserat Sverige. Det är dock inte helt enkelt som enskilt, mindre företag att exportera sina produkter. Detta arbete syftar till att lyfta fram framgångsfaktorer hos livsmedelsföretag som redan är väletablerade på den internationella marknaden och som under en tid har bedrivit en framgångsrik exportverksamhet. Det är en kvalitativ studie och det empiriska materialet är baserat på tre semistrukturerade telefonintervjuer med livsmedelsföretag från Halland och Skåne. Begreppen resurs, nisch och ??Dynamic capabilities?? samt ramverket VRIO har varit viktiga vid analysen.
MEMS baserad referensoscillator
The interest in tiny wireless applications raises the demand for an integrated reference oscillator with the same performance as the macroscopic quartz crystal reference oscillators. The main challenge of the thesis is to prove that it is possible to build a MEMS based oscillator that approaches the accuracy level of existing quartz crystal oscillators. The MEMS resonator samples which Philips provides are measured and an equivalent electrical model is designed for them. This model is used in the simulations of the Pierce oscillator and the transresistance amplifier oscillator that are evaluated in this thesis. Finally the Pierce oscillator is implemented in the A BCD2 process and manufactured at Philips Semiconductors in Nijmegen, The Netherlands.
Skadliga nollflödespunkter i Fortum Värmes fjärrvärmenät i Stockholm : En analys av dess förekomst och effekter
When several production units provide a district heating network, water is pumped from different directions. When the flows from the plants finally meet in the network, the water can be completely still. These places are called zero flow zones. In district heating networks with several plants, which also have different supply temperatures, large and frequent temperature fluctuations can occur when the zero flow zones move. This may cause wear on the pipes, a phenomenon called low cycle fatigue.For this reason it is important to examine where and when zero flow zones that cause temperature changes occur.
Modellstudie av föroreningsretention i Bäckaslövs våtmark : Tillämpning av modellverktygen MIKE SHE WET och MIKE 21
During the nineties, ecological handling of urban storm water became very popular in Sweden. Together with Chalmers University of Technology and two Swedish communities, DHI Water and Environment has been doing research of storm water ponds and constructed wetlands. This thesis work is a part of that research project. The work has been applied at the Bäckaslöv storm water treatment plant in Växjö, Sweden. The plant consists of one storm water pond and a downstream constructed wetland.
Utvärdering av en Magnetic Harmonic Traction Drive
In this report a new gear concept is evaluated using the magnetic finite element method (FEM)software MagNet and Ansys as well as the mechanical FEM software Abaqus. The gear conceptis evaluated in terms of maximum torque capability, torsional stiffness, gear ratio and efficiency.ABB Corporate Research has proposed a new gear concept which should be less expensive thangearboxes used today. The new concept is called aMagnetic Harmonic Traction Drive and usesthe principles of a harmonic drive gear to achieve a high reduction ratio. The gear conceptreplaces the wave generator used in traditional harmonic drives with magnets and uses tractioninstead of gear teeth to transfer the torque. The main components in the gearbox are the magnets,the flexspline, the magnetic portion and the circular spline.
Energieffektivisering av industribelysning : Planering av belysningsanläggning i mekanisk verkstad
In Uppsala, Sweden, Vattenfall has a combined heat and power plant. On the premises there is an engineering workshop with old fluorescent and mercury lamps that need to be replaced. This provides a great opportunity to save energy and money by installing more efficient lighting. The main purpose of this study was to present two functional and energy efficient lighting systems including control system. The lighting systems were designed by investigating the working environment, measuring illuminance and by simulations in the software DIALux.
Developing Dynamic Outsourcing - Bringing continuous added value to the ABB Full Service partnership
Executive summary This master thesis was originally based on a specific assignment given to the authors from ABB Full Service, a unit specializing in providing maintenance outsourcing: ?How can ABB Full Service expand its offering of providing fundamental maintenance by seamlessly incorporating the business concept with competencies and solutions from other ABB divisions?? The academic issue was developed throughout the thesis, resulting in the following formulation: ?From an organizational perspective; how can service providers bring continuous added value to intra-organizational outsourcing partnerships?? Many of the key findings of this thesis are reflected in the issue. The term intra-organizational outsourcing is a proposed addition to the terminology in the academic discourse on outsourcing. The definition of the term is: ? Where an organization outsources a business process interlinked with the physical operations, requiring the service provider to take over a preexisting unit and its employees.This is an accurate description of the form of outsourcing that ABB Full Service is engaged in.
Frekvens och spanningsskalning i en inbyggd mikroprocessor; for att mojliggora implementationen av schemalaggning med stod for dynamisk frekvens- och spanningsreglering for energihantering.
Minimizing power consumption is a critical part of many embedded design projects. Thechallenge is to limit the power consumption of the system and at the same time providesatisfactory service to the user. With regards to microprocessors, the main way of limiting powerconsumption during program execution is to adjust the frequency and the voltage at which theprocessor operates.To enable the implementation of real-time scheduling with support for dynamic voltage andfrequency scaling, an exhaustive study of the Freescale i.MX31 embedded microprocessor isperformed. Specifically, the power consumption relationship to all relevant frequency andvoltage settings is investigated. In addition, to enable frequency and voltage scaling in a real-timeenvironment, a complete timing analysis of proposed voltage and frequency scaling methods isperformed and their suitability for use in real-time systems is evaluated.To integrate voltage and frequency scaling capability into OSE RTOS, a software module hasbeen developed for this operating system.
Uppskattning av Ytkurvatur och CFD-simuleringar i Mänskliga Bukaortor
By applying a segmentation procedure to two different sets of computed tomography scans, two geometrical models of the abdominal aorta, containing one inlet and two outlets have been constructed. One of these depicts a healthy blood vessel while the other displays one afflicted with a Abdominal Aortic Aneurysm. After inputting these geometries into the computational dynamics software FLUENT, six simulations of laminar, stationary flow of a fluid that was assumed to be Newtonian were performed. The mass flow rate across the model outlet boundaries was varied for the different simulations to produce a basis for a parameter analysis study. The segmentation data was also used as input data to a surface description procedure which produced not only the surface itself, but also the first and second directional derivatives in every one of its defining spatial data points.
Konstruktionstudie av en ångexpander
This thesis applies to a novel steam expander, one part of a steam engine system, a wobble plateengine. The piston in the expander moves axially with the outgoing rotating shaft and is locatedon a plate, why the engine type is called axial engine. When steam is applied to the plungers theplate wobbles creating a rotation on the shaft going thru the wobble plate. The steam expander issupposed to be used in exhaust gas recovery (bottoming cycle) applications and small scaleenergy production. The commissioner is Ranotor Utveckling AB.
Från jag till vi : en essä om strävan efter en god gruppdynamik och sammanhållning
Life is for us humans a social life. We are constantly in different social communities with various purposes. Throughout life we are part of different groups, for better or worse. The basic social communities, in our society, are the groups we live, work, learn and grow in. This essay deals with the groups children develop and learn in, in school and leisure time center.