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1343 Uppsatser om Flow simulation - Sida 11 av 90
Opera i Stockholm, Stadsgårdskajen
The report is about efficiency of a current production group where there is no clear production flow and there are some buffers between the operations. The efficiency is done with the help of a tool that is calledWork process of flow production which is used by Atlas Copco CTO. The most obviously results are that the lead time drops from 25 hours to 425 minutes and that the balancing loss decreases from 85 % to 8 %. The report focus on decreasing transports, decreasing buffers, more reliability in lead time and quality. And a more stimulating labour content for the workers is another result..
En tand för en tand och en våtmark för en våtmark - ett återskapande värt pengarna? : En undersökning av nyttan och kostnaderna av att restaurera våtmark med hjälp av Contingent Valuation Method.
The goal of this study is to examine what five teacher?s impression of the teacher?s role is in their previous years. How important the ?joy at work? is in relation with the educational progress? And what aspects that contributes to the? joy at work? and what obstacles that stops them. The essay will also go through the concepts of a teacher role, with connection to the theoretical perspectives of Csikszentmihalyi?s Flow and Antonovsky?s Salutogenesis (KASAM).The method I used was interviewing five teachers and I used Larsen?s chapter of ?content analysis? as a basis, I also used Flow and KASAM as theoretical references in my analysis.
Robotiserad produktionsanpassad magnetmontering för vågkraftverk
This thesis work includes studies and simulation how magnetization of the translator in a linear generator for wave power can be automated. The translator is the moving component in the generator that is "dressed" with permanent magnets. The translator is magnetized with rectangle-shaped permanent magnets that are today's strongest permanent magnet type of neodymium-iron-boron (NdFeB).Eight equivalent metal sheets are mounted around the translator. The plates have milled tracks where 106 permanent magnets per sheet are mounted. Today the assembling of the magnets is done by hand, which is a very tedious and time-consuming work. This project presents investigations about the automation of the translator magnetization theoretically and simulation results are preformed in ABB's robot simulation software RobotStudio. Even robot-held tool was designed that enables the robot to be able to magnetize the translator in a simple manner. The investment cost is roughly 1.5 million SEK. With an economic life-time of five years, the investment costs are estimated to 24000 SEK / month. According to the calculations, this project is very motivated to implement, as it provides savings up to 17 000 SEK per translator which is 10.2 million SEK assuming that the robot cell is operating at full speed the whole year.According to this thesis work the result is a 4x9 meter cell with two industrial robots of the type ABB IRB6650S.The cycle time to magnetize one translator was calculated to about 10 hours.This prototype of project can possibly be implemented in a full-scale production line and performed according to the calculations and simulations presented in the report. Further work is suggested to improve the tool.Lyssna .
En flödesutjämnande driftstrategi för Uppsalas fjärrvärmesystem : En ändrad styrning av framtemperaturen
This thesis examines a possible control strategy to minimize flow fluctuations in Uppsala?s district heating system. High variations in flow rate may lead to complications caused by hydraulic constraints in the district heating system. These complications, such as inadequate pressure and temperature levels, increase the risk of heat delivery failures. It is therefore important to avoid such situations both for the producer and for the customers.Typically, the forward temperature is controlled by using a rough correlation with respect to the outdoor temperature.
ADS och Matlab för optimering av pre-distortion av effektförstärkare
This master?s thesis deals with integrating simulations using Agilents Electronic Design Automation tool ADS with customized Matlab scripts, for solving complex analog and digital radio architectures. In particular, it addresses predistortion, realized in the digital domain, of power amplifiers, modeled in the analog domain. The former is implemented in Matlab while the latter is implemented in ADS. Two versions of integrating the two systems have been tested: 1) Iterative approach on sample basis and 2) Scheduled batch solution by matrix inversion.
Modell och analysverktyg för beräkningav frekvensförlopp
The power system modelled in this thesis work has been developed for simulationwhen e.g. the production in some part of the power system is changed. The powersystem has been modelled according to the swing mass of the system, the frequencydependency of the load and the turbine governor. The model determines the systemfrequency, the period of regulation and the power exchange between the differentsubsystems in the Nordic synchronized system.In this model the system frequency is assumed to be the same in all different parts ofthe power system and the voltage conditions in the power system are neglected. Forthat reason power swings does not occur between different subsystems in the powersystem, which usually occur as a result of the swinging connection between thetransmissions line.
Effektivisering av produktionsgrupp : Improving the efficiency of a production group
The report is about efficiency of a current production group where there is no clear production flow and there are some buffers between the operations. The efficiency is done with the help of a tool that is calledWork process of flow production which is used by Atlas Copco CTO. The most obviously results are that the lead time drops from 25 hours to 425 minutes and that the balancing loss decreases from 85 % to 8 %. The report focus on decreasing transports, decreasing buffers, more reliability in lead time and quality. And a more stimulating labour content for the workers is another result..
Energieffektiviserande åtgärderpå Robertsfors VA-nät : En förstudie av vilka energieffektiviserande åtgärdersom kan göras på pumpstationer och reningsverk
The objective of this work was to introduce measures to reduce energy and water demand at Gävle Söder 17:10. To succeed, this energy audit has been made. The work is based on collected statistics from the property owner Norrporten, measurements, literature review and through consultation with experts in the field. Two models, one for each building, have been created in the simulation program BV2 to estimate the potential of energy measures based on the collected information. The models in BV2 have been verified against the statistics of the energy consumption.With the help of calculations and simulations, seven cost-effective measures have been identified.
Småskalig vattenkraft vid Olofsfors bruksmuseum : Med faunapassage
In Sweden there are 1894 small-scale hydropower plants in operation, which together generate 4.3 TWh of electricity per year according to Swedish hydropower compound (SVKF, 2011). This corresponds to the annual consumption of about 860,000 Swedish households (based on an annual consumption of 5000 kWh). In the mid-1950s there were around 4000 small-scale hydropower plants in operation in Sweden before cheap fossil fuels and uranium competed with them, in the current situation only 1,894 of these are in use. If slumbering small hydropower plants once again would be taken into use and some new ones are built, we would be able to extract about 7 TWh of renewable electricity from these annually in Sweden, representing about 1.4 million households.The thesis intends to calculate and construct a hydroelectric power plant at the existing dam in Olofsfors and give suggestions on how the power station should run during the time that fish migration is greatest in Leduån.The turbine and generator to the station in Leduån at Olofsfors is designed by the height of the fall and the water flow through the dam. The turbine selected for the station is a CK-1000RM turbine with a 4-pole 250 kW generator from Cargo & power turbine Sweden AB, which is expected to deliver 1.2 GWh per year.
Syntes och egenskapskarakterisering av volframoxid framställd med magnetronsputtring
The system tungsten-oxygen has potential of being suitable for decorative coatings since ceramic coatings are often hard and wear resistant, and since modulations in oxygen content or incorporation of small ions could give bright colours. The aim of this report was to investigate the relationship between process parameters and the properties of the films, with the wear resistance being of special interest.Samples with tungsten to oxygen ratios in the range of 100:0 to 25:75 at% were made using reactive sputter deposition, either with constant gas flow, or gas flow controlled by optical emission of the plasma. The hysteresis of the system, which means that a certain gas flow will cause different pressure and/or target voltage depending on in what way the flow is reached, makes it interesting to control the process where the system makes the steep change from metallic tungsten to ceramic tungsten oxide. This is difficult and thus requires precise control equipment.The samples were analysed using X-ray diffraction, X-ray photoelectron spectroscopy and an empirical wear test suitable for small components like cell phone cover for example, in order to characterize the structure, composition and wear resistance of the coatings. The results could be divided into three groups: (I) tungsten-like, with very low oxygen content; (II) mixed phase and (III) tungsten oxide like, with oxygen content close to 75 at%.
Beteende hos lekvandrande lax i Klarälven ? utvärdering av en fiskfälla
During the migration season in 2013 a study on spawning migrating salmon and the effect of water flow on the behavior was conducted of the salmon at the Forshaga hydropower station in the River Klarälven. The River Klarälven with its nine hydropower plants on the Swedish side, constituting migration obstacles for the migrating salmon. Fortum Generation AB has together with the County Administrative Board restored a salmon trap at the lowermost hydropower station in Forshaga, aiming at making it possible for the salmon to swim into the trap, and thereafter be transported by truck past the power plants and then continue their journey to the spawning grounds on their own. Unfortunately, it is believed that the trap does not work as well as it should. In this study, I focused on salmon position in relation to water flow and if the number of salmon that swam into the fish trap differed between salmon with previous experience of the trap (experienced) and salmon without experience (unexperienced).
Just In Time : Effektivisering av materialflöden med hjälp av principer från Inventory Management och Production Management
AbstractManagement is a field that started getting attention in the beginning of the 20th century by Frederick Taylor. His publication is called the Principles of Scientific Management and is based on the principles of using scientific methods to find the best way of conducting each operation within a production facility. Many of Taylor?s principles may appear obsolete today but the matter of an effective material flow is still highly current. Efficiency is the relationship between the input into an operation and its result.
Flödesoptimering i begränsande resurs
Most companies have a bottleneck in their production, that is a constraining re-source. When the demand is higher than the capacity in the constraining resource it is impossible to produce the demanded output. This problem leads to delayed deliveries, unhappy customers and ultimately to decreased revenue. Bottlenecks therefore has a significant role in production and must be handled thereof.MW Power in Sävsjö, Sweden designs and manufactures water and steam boilers for the customer's unique needs. MW Power invested in a new plasma cutting ma-chine but the machine has not reached the expected capacity.
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.
Välbefinnande och Känsla av sammanhang bland flickor i skolvardagen (ÅR 6)
I ?Skolbarns hälsovanor? har sedan 1985 frågan ?Vad tycker du om skolan nu för tiden?? funnits med. Skoltrivseln minskar med åldern och till skillnad från många andra frågor skiljer sig pojkars och flickors uppfattning i denna fråga mest i den yngsta åldersgruppen, då flickorna i högre utsträckning uppger att de trivs mycket bra i skolan (Svenska barns hälsovanor, FHI 2005). I den här studien undersöks hur åtta 12-åriga svenska skolflickor i en västsvensk småstad upplever sin skolvardag. Min metod har varit att fastställa deras KASAM-värde genom en enkät (Margalit & Efrati, 1996) baserad på Antonovskys frågeformulär för att mäta Känsla Av Sammanhang (Antonovsky, 1987)och sedan intervjua dem enskilt om trivsel, flow och beröm i skolan.