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119 Uppsatser om Patch loading - Sida 3 av 8
Utvärdering av den bärande tegel- och betongstommen i en byggnad från år 1916
This Master thesis is about a postal- and telegraphic building in Eskilstuna, Sweden. The construction methods for the specific building and buildings in general from the same time are described. The purpose of the report is to describe the loads acting on the building and how it has been built and why it has been rebuilt during the years. After this, possibilities of reconstruction and adaptation for today?s demands can be evaluated.
Energieffektivisering av luftningssteget på Käppalaverket, Lidingö
This master thesis in energy optimization was made during the autumn of 2006 at Käppala wastewater treatment plant in Lidingö, Stockholm. A preceding thesis, where all electricity consumption was mapped, showed that the aeration in the biological treatment is the single largest consumer in the plant, and it is therefore of interest to reduce this cost. The oxygen control strategy used at Käppala WWTP is working well from a nutrient removal point of view, but not from an economic one. The last aerobic zones have a very low oxygen consumption during low loading periods which give rise to enhanced dissolved oxygen concentrations with excessive costs and reduced denitrification as a result. But also during periods of normal loading unnecessary high oxygen concentration are sometimes given.By modifying the aeration control strategy three full-scale experiments have been made, with the intention to reduce the air consumption.
Interactions between some plant-parasitic nematodes and Rhizoctonia solani in potato fields
The pathogenic fungus Rhizoctonia solani causes major economic losses for potato producers in Sweden. The producers, as well as advisors, have reported possible increases in severity of R. solani when free-living plant parasitic nematodes are present and active. There are several examples in the literature of interactions between pathogens where one, or both species, support or increase the damage made by the other organism. These complexes are important to investigate and to be able to forecast, since even low incidences of fungi or nematodes may result in an interaction of significance.
Gårdsbaserade system för spannmålshantering i den framtida Lantmännenorganisationen :
The Swedish cooperative Lantmännen Ekonomiska Förening has initiated a project labelled "Operation Blåljus" that includes an extensive program for closing down elevators. The number of elevators will be reduced from 92 to approximately 15 after harvest of 2007. The objective of Blåljus is to increase the price of grain with 10 öre/kg. A project has been initiated at the Lantmännen Grain division where the purpose is to provide the farmers with support in their decisions and practical advice how they can load a 35 ton grain truck on 30 minutes. The result from the project will serve as a support system to the farmer in his ambition to achieve cost efficient systems to load a truck with grain on the farm.
En studie av landskapsindex för kvantifiering av rumsliga landskapsmönster
Syftet med uppsatsen är att utvärdera två landskapsindex: ett formindex som beräknar formen för varje markanvändningsyta ( eng. "patch"); ett diversitetsindex, som beskriver de olika markanvändningarnas relativa utbredning. Formindexet beräknas på två olika sätt, beroende på om dess storleksberoende inkluderas eller ej. Utvärderingen körs för ett landskap på cirka 50 km2, men även för tre mindre områden i landskapet: åkerbygd, mellanbygd samt skogs-bygd. Samtliga områden jämförs sedan i två olika skalor, flygbild respektive satellitbild..
Ny stamstation i Yttermalung för anslutning av vindkraft : Nätstudie av olika utföranden i normal- och reservdrift
Since 2004, wind power has had the largest installation of new capacity compared to other energy sources in Sweden. Accommodating new wind power may require strengthening or rebuilding of the existing grid in areas where the grid is already loaded to maximum capacity. This master thesis examine the possibility of a new 400/130 kV substation in Yttermalung, Sweden, with a connection to the two neighboring regional grids in Dalarna and Värmland owned by Fortum. This substation would provide a new connection point to the Swedish transmission system as well as an interconnection of the two, currently separated, regional grids. Different expansion scenarios where a substation with and without series compensation or a phase shifting transformer (PST) to control active power flow were studied.
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.
Optimering av sintrade kugghjul
Powder Metal (PM) gears are machine element components which operate under the same principle as conventional gears, but, due to their intrinsic material characteristic need to be designed slightly different, and its manufacturing process offers advantages previously unobtainable by conventional steel gear manufacturing methods. The use of PM in similar applications, such as synchronous hubs, makes them a suitable candidate for production in such material. The current master thesis work focuses on gear design using PM by utilizing finite element method (FEM) to reduce weight and inertia taking into account root bending strength and tooth deflection.First a topological optimization is used to determine feasible candidates for different web designs which have as objective to reduce volume, similar topologies were shown during different loading conditions; and hence, this topology was chosen as a suitable candidate. A shape optimization of the topological candidate was performed having as state variables root bending strength, independent for compressive and tensile side of the tooth loading; and tooth deflection, which in concept can be correlated to static transmission error (TE).Another aspect in this thesis analysed is the possibility to incorporate non-trochoid root geometry, a trochoid root is always present when machining with a hob, into the gear root and hence reduce the stress concentration here. Due to the use of PM, a non-symmetric optimized root can be achieved and hence be optimizing compression and tension.Results showed significantly lower inertia, for example certain results showed 40% reduced when compared to solid gear, with adverse effects as increase in tooth deformation and increase in maximum principal stress.
Konceptstudie av drivmodul till bandskotare med hybriddrift
BAE Systems Hägglunds has a long history of producing high performance terrain tracked vehicles (mostly for military applications), and they are now aiming at developing a tracked forwarder with similar techniques.The forwarder will be of series hybrid type where a diesel engine via a generator will power the motors (one for each drive wheel). Thanks to individually controlled motors and the gentle rubber tracks, this forwarder is calculated to have a considerably higher average speed in the terrain and to be more gentle to the soil. The forwarder with a weight of 11 metric tons and a load capacity of 15 metric tons is specified to have an average working speed of 7-10 km/h, a top speed in terrain of 15 km/h and a top speed on roads of 40 km/h.This master?s thesis aims at developing a conceptual design of the forwarder?s drive module which includes electric motor, gear unit, brake and drive wheel.To investigate if the requirements can be fulfilled a study of the dimensioning loading scenarios has been carried out. The resulting needs regarding the torque has been considered in order to determine the required gear ratios for different motor options.
Termomekanisk utmattning av Sanicro 25 : Materialmodellering med finita elementmetoden
The report aims to describe the austenitic stainless steel Sanicro 25 from a thermomechanical point of view. The thermal and mechanical properties of the material make it suitable for use in coal ? and thermal power plants. By the use of Sanicro 25 it would be possible to bring the efficiency of these plants up while bringing the carbon emissions down.A material model is created from material testing and validated through simulation in the finite element software Abaqus. The model that has been derived describes the material behavior during loading and stress relaxation for the first cycle in a thermomechanical fatigue test well.
Biogaspotential vid samrötningav mikroalger och blandslam från Västerås kommunala reningsverk
Because of the increasing trends in energy consumption and increased environmental awareness, greater focus has been placed on improvement and development of renewable energy sources. An already proven and accepted method is biogas production from anaerobic digestion at municipal wastewater treatment plants.In the waste water treatment process solid material and dissolved pollutants are separated from the water, forming a sludge. The sludge is separated from the process and stabilized during anaerobic digestion or aerobic aeration. Most often, mesophilic anaerobic digestion is used. Because of degradation by microorganisms, biogas with a high content of methane is formed during the digestion.
Utvärdering av kalkstens egenskaper med laboratorie- och fältmetoder.
A pavement construction designed to cope with the different type of traffic loads; it is exposed to and at the same time it can resist the effect of the climate. A road structure consists of sub- and superstructure which is divided by a boundary known as terrace. During the construction of unbound layers (base course and sub-base course) in the superstructure, it is always ensured that the material meet the requirements for bearing capacity and the degree of compaction. These parameters are controlled by various laboratory tests and control methods. To obtain increased knowledge of the material and improve the quality of the compaction in the field, it is necessary to perform laboratory tests in order to determine material properties.A base course material 0/ 32 mm limestone from Gotland (Hejdeby) was investigated in this study.
Konstruktion av provladdareför singelmolekyldetektor
This report describes the development of a sample loader for my diploma work at Q-linea AB in Uppsala. The sample loader will replace the process of loading fluid samples into Q-linea?s instrument for biomolecule analysis. The earlier process was done by hand and was a time consuming and inefficient task.The work was initiated with a design phase where an overview of the system was created. The sample loader will be receiving text commands from a PC that coordinates all the subsystems like pumps and lasers on the analysis instrument.
Experimentell undersökning av provkroppar för trälimfogar
This thesis engages the topic of test methods for wood adhesives. Two test methods were evaluated, EN 302-1, a European standard, and ASTM D905, an American standard. The total amount of specimens manufactured and tested was more than 500. The adhesive bonds were tested in shear with an increasing load on the specimen until failure.The adhesives used were epoxy-resin, phenol-resorcinol-formaldehyde and a 2-K polyurethane. The test programme included five different types of intentional errors per method, in order to investigate the sensitivity of the test methods.
Senior Concept Vehicle
We can see an increasing middle age population in large parts of the world. People are healthier when they retire than they were before. As people grow older, physical and mental changes occur that can make the use of cars more complicated. The possibility to travel by car is important for many people to keep the connection with the society and to feel independent. How can Volvo cars face the needs of this growing target group?The purpose of this project is to make a car concept that responds to those needs, it is therefore important to maintain the values of Volvo cars.