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1343 Uppsatser om Flow simulation - Sida 49 av 90

Simulation driven design of optimized sheet metal bracket

Det ständigt ökande trycket på minskande utsläpp och effektivare energianvändning driver utvecklingen av Scanias produkter. För att varakonkurrenskraftiga på marknaden behöver man leverera lastbilar med högre kvalitet och lägre bränsleförbrukning, det vill säga sänka transportkostnaderna förkunden. Ett steg i detta är att utveckla komponenter i fordonet som är optimerade iförsta hand med avseende på hållfasthet men även mot vikt och pris. En betydande andel av lastbilens komponenter är plåtfästen som ofta underprioriteras i produktutvecklingen. Examensarbetet fokuserade därför på att utveckla metoder för konstruktion av plåtfästen.En metod för att förbättra konstruktionerna är att arbeta med simuleringsdriven konstruktion.

Påverkas röstkällans egenskaper av förändrad stående kroppshållning? En experimentell studie av otränade mansröster

The aim of this study was to investigate whether a direct shift inpostural alignment results in changes in voice source characteristics. Ninemales with untrained voices were recorded standing in ideal posturalalignment and in the deviant postures swayback and kyphosis characterizedby extended hips and a slump back respectively. The voice source wasderived from the audio signal by inverse filtering. The parameters pulseamplitude, maximal flow declination rate, level difference between the firstand second voice source partials, closed quotient and the normalizedamplitude quotient in relation to subglottal pressure were compared betweenideal postural alignment and swayback and kyphosis respectively. Resultsindicate an impact of changed postural alignment on the voice source.Swayback posture gave significantly less pulse amplitude and maximal flowdeclination rate and significantly higher subglottal pressures thus resulting ina less effective phonation.

Skydd mot yterosion i slänter av finmorän

Slopes in fine till soils are exposed to surface erosion due to rainfall, snowmelt and upland water sources. Large areas of road slopes are therefore covered for surface erosion protection. Preventive methods like ditches and trenches are also being used. Silt tills are particularly troublesome since the water can bring the soil into suspension and cause mudslides. Different methods for erosion protection have been studied in this work, with the emphasis placed on rockfill covering. The need for and the dimensioning of this type of covering has been examined in literature and field studies.

Vattennivåreglering i Avesta Lillfors : På uppdrag av Fortum Generation AB

I denna rapport utreds olika metoder för att kunna reglera vattennivån i vattenkraftverket Avesta Lillfors i Dalarna. Två kraftverk ligger endast 900 m uppströms och detta gör att svarstiderna blir korta och regleringen blir lätt nervös. Att använda sig av vattennivåreglering i ett kraftverk för-enklar dess styrning då anpassning till inflödet sker automatiskt.En flödestabell har tagits fram genom mätningar i turbinen, med hjälp av Winter-Kennedy-metoden. Denna tabell används för att kunna fram-koppla regulatorn och därmed dämpa stora variationer i inflödet. Dessu-tom har en modell av älven skapats och testats med en återkopplad PID-regulator.

Avbördningskapacitet för Traryd kraftverk: en modellstudie vid dimensionerande flöde

Sydkraft Vattenkraft AB owns and operates the Traryd hydropower plant, located in the river Lagan in the southern part of Sweden. The gravity dam is classed according to RIDAS guidelines (Hydropower Industry Dam Safety Guidelines) as a class 1B dam. This means that the dam must discharge a class 1-flow which has a return period of 10 000 years. The inflow into the dam has been calculated in an earlier report to 495 m3/s, with a waterline at an elevation of 126, 3 meters above sea level. The gravity dam has a discharge system with two rectangular weirs, which results in a smaller discharge than the necessary 495 m3/s.

"Don´t put lipstick on a pig"

Spelifiering har funnits genom historien, utan att det tidigare har definierats. Spår av användning av begreppet finns på Internet sedan 2004, men begreppet blev populärt först runt 2010. Spelifiering kan beskrivas som en process där det lånas komponenter och upplägg från spelvärlden som appliceras på verksamheter som traditionellt inte hör samman med spelande. I vår undersökning riktar vi in oss på kopplingen mellan spelifiering och lärande, alltså spelifierat lärande. Syftet med denna studie är att ur ett diskursanalytiskt perspektiv beskriva vad det är som kännetecknar spelifierat lärande.

Småskalig biobränsleeldad kraftvärmeproduktion : teknik och investeringsutrymme

To achieve the requirements to decrease emissions of greenhouse gases by 20 % by 2020, Swedenneeds to increase its use of bioenergy. In doing so it seems natural that those who already haveaccess to large amounts of biofuels in the form of by-products such as straw, wood chips anddigestible materials take advantage of these assets locally. By combining production of heat withpower production at the farm it may be possible to not only reduce the direct use of fossil fuel forheating but also reduce energy costs.The purpose was to simulate different cases of using a small scale biofueled combined heat andpower plant for farm-based systems. A MatLab-model was developed and used to draw conclusionsabout the costs for production of heat and electricity with different conversion technologies.The model uses climate data to simulate the variations in heat energy demand on a day-to-day basis.The given heat demand is the base of the simulation and from this the possible electric output iscalculated. This study has focused on the impact of the following properties: electric-, heat- andtotal efficiency, fuel, fuel price and specific fuel requirements.

Reglerbara skovlar på pumphjul

The thesis investigates if it is possible to replace several pumpimpellers with one controllable pumpimpeller, with a economical and a manufacturing analisys aspect. The studied pumpimpeller is mounted on a midrange wastewaterpump, N3127MT.In the thesis a contemplated manufacturing process is evaluated for a concept that are supposed to act as a controllable pumpimpeller. The pumpimpeller are studied in a manufacturing and flow matter and are presented in the thesis.The manufacturing cost is also estimated, and this has been compared to the storage cost and other costs that the existing pumpimpeller generates.The thesis also shows that the concept has minor losses in cutting quality aswell as the effiency comparing to the existing pumpimpeller.The concept also raises the manufacturing cost and this increasing cost makes the presented concept to expensive to carry through.An investigation of the costs that the existing pumpimpeller produces has also been done, and this shows that there is not that much expenses to earn regarding to for example the storage cost. The storage cost includes information from Flygt?s central storagecenter in Lindas, Sweden and Metz, France, and also an inventory about the pumpimpellers located at Flygt?s different distributors worldwide.The thesis shows that a controllable pumpimpeller will generally increase the cost for the pumpimpeller and the performance of the pumpimpeller will decrease..

Dokumentation av en experimentell biogasanläggning

This thesis is   focused on identifying and documenting all   electrical equipment, such as devices, power lines / cables, and connectors in the facility and also on presenting a brief   technical description and information of the systems around the reactors.   Furthermore there will be a brief description of LabVIEW - which is a   graphical programming language- and which devices / elements   are programmed. For further notification, I am not   responsible for the programming of the devices in LabVIEW   which I have only used as a tool in my work. The plant   for production of biogas consists of four reactors   of which the third reactor (Lakbädden)   is connected to another reactor (UASB)   where they cooperate with each other.   The reactors are used for producing   biogas in the form of methane gas.The reactors I and II are   connected to, various electrical devices as, flow meters, temperature   sensors, frequency converter and   more.

Ekologisk dagvattenhantering på parkeringsytor : Lösningsförslag för Eurostop köpcentrum i Halmstad

Stormwater from trafficked areas often contains high pollution levels. In traditional stormwater management design, stormwater is first transported away through piped networks, and then in most cases passes through oil separators before finally reaching the recipients. While this traditional method removes certain pollutants from the stormwater, it does not reduce the total flow, as in the case of ecological stormwater management. In the ecological method the stormwater is not simply transported away, but is recirculated through infiltration, percolation, and detention. The aim of this study is to investigate possible advantages of ecological management designs, in contrast to traditional management.

EN OMGÅNG TILL? : Dynamisk svårighetsgrads påverkan på återspelningsvärde och inlärningskurvor inom casualspel

Arbetets syfte är att undersöka hur användandet av dynamisk svårighet i jämförelse mot användningen av statiska svårighetsgrader påverkar ett casualspels återspelningsvärde och huruvida spelare upplever inlärningskurvan annorlunda. De teorier som ligger grund för arbetet fokuserar kring två områden, där det ena är hur dynamisk svårighet utformas på bästa sätt och vilka fördelar det skulle kunna bidra med. Det andra kretsar kring casualspel och varför casualspel har haft den framgång och vad det är som tilltalar spelare att spela dem samt vad det är som ger spel återspelningsvärde och väl utformade inlärningskurvor. För att utföra undersökningen har två versioner av ett casualspel, vars spelmekanik fokuserar runt skrivhastighet på tangentbord, utvecklats där den ena använder sig av dynamisk svårighet medan den andra använder sig av tre statiska svårighetsgrader. Resultatet från undersökningen visar inte på ett direkt samband att dynamisk svårighet skulle ge ett spel högre återspelningsvärde men att några av de problem som uppstår vid statiska svårighetsgrader kan lösas.

Evaluation of Xilinx System Generator

This Master?s Thesis is an evaluation of the software Xilinx System Generator (XSG) and blockset for Matlab. XSG is a module to simulink developed by Xilinx in order to generate VHDL code directly from functions implemented in Matlab. The evaluation was made at Saab Avionics AB in Järfälla, north of Stockholm. In order to investigate the performance of this new module XSG to simulink, a model of a frequency estimator often used in digital radar receivers were implemented in Matlab using XSG.

Kromatografi av polära läkemedel och metaboliter med HILIC-teknik

The purpose of this project was to investigate if retention of polar compounds that are given to treat tuberculosis, diabetes, inflammatory bowel disease and childhood leukemia could be obtained with HILIC separation. By varying different parameters for different types of columns the compounds were analyzed with the aim of finding guidelines for future method optimizations. To perform these analyzes three different columns were tested ? ZIC-HILIC (silica-based with zwitterions), ZIC-pHILIC (polymer-based with zwitterions) and XBridge Amide (amide functions). The results were evaluated with selected quality measures.

Sociala medier ? strategier,möjligheter och risker

Social media, with its immense and continuous flow of information, has in recent years growntremendously in terms of users and content. This increase has led companies and organizations keen to be seen within these channels of communication, but do they always have a clear idea of how andwhy, and are they aware of the risks that are associated with it? Current research on social media is somewhat divided in two. The debate concerns, among other things, what value the information on social media has, and whether the media is really a good communication channel or not. This raises several questions, for example can a company really afford to remain outside of social media with allthe information it generates? This research aims at answering these questions in order to further understand how organizations discuss social media presence and strategies.

Problem med lageranknytning hos en bilåterförsäljare

In this paper we have looked closer on a car-retailer in the middle of Sweden. We have chosen to dig deeper in the different problems that can occur, related to the supply. Soon we realized that that the problems weren?t related to stock management. Through studying the whole of the company, we have identified reasons to why details aren?t in the stock.

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