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710 Uppsatser om Carbon and peat filter - Sida 20 av 48
Grundvattensänkning till följd av järnvägstunnel genom Hallandsås : miljökonsekvenser relaterade till förändrad kväveomsättning i mark
This thesis was carried out to give some background information to a report of SLU (Swedish University of Agricultural Sciences) for the Swedish National Rail Administration (Banverket). The requested information was to provide basic data for an environmental impact assessment of the construction of the tunnel through Hallandsås. The aim with the thesis work was to discuss and quantify the leaching of nitrate and the emission of nitrous oxide from the soil at the groundwater level established through the tunnel project. The nitrogen related processes that could be affected were described and discussed. The different areas where a decreased groundwater level can cause changes in the nitrogen processes are the wet and moist areas.
Missilstyrning med Model Predictive Control
This thesis has been conducted at Saab Bofors Dynamics AB. The purpose was to investigate if a non-linear missile model could be stabilized when the optimal control signal is computed considering constraints on the control input. This is particularly interesting because the missile is controlled with rudders that have physical bounds. This strategy is called Model Predictive Control. Simulations are conducted to compare this strategy with others; firstly simulations with step responses and secondly simulations when the missile is supposed to hit a moving target.
Layoutgenerator för en multiplikator i "overturned stairs" trädstruktur
Multiplikatorer används ofta som ett byggblock vid konstruktion av kretsar som digitala filter, FFT-processorer och aritmetiska enheter. Olika trädstrukturer används i"höghastighet"applikationer för multiplikatorer. En typ av träd,"overturned-stairs"(OS) som är ett adderarträd av första ordningen har uppvisat lika optimal prestanda med avseende på hastighet som Wallace-träd, vid 18 eller färre ingångar. I moderna integrerade kretsar, ger ledningar och kopplingar upphov till fördröjningar och parasitiska laster. I en jämförelse mellan Wallace-träd, och OS1-träd har det sistnämda kortare och mindre komplicerad ledningsdragningar och är därför mer ändamålsenlig för VLSI implementationer..
CarEye ? Sees & Saves: Fordonskamera för skadedokumentering
In the middle of Australia there is a city called Alice Springs. The city has one of the highest amounts of daily sunshine hours and sun irradiation in the world. The Australian Government runs a project called Solar Cities, and Alice Springs is one of the participators. The main part of the goal with the Solar Cities project is to increase the amount of electricity generated by solar power and by doing that lower the impact on the environment. This thesis examines the possibilities for construction of a large scale solar power plant in Alice Springs. This is done to determine the potential of creating a more sustainable energy system in the city.
Förskollärares kunskap om stress och stresshantering bland barnen på förskolan
This work examines the students´ thoughts on climate change with a focus on carbondioxid through photosynthesis and the carbon emissions from cars. The study is based on two subject areas, one with a focus on enhanced greenhouse effect, and the other focusing on photosythesis. The survey was conducted by means of qualitative interviews with students in grades four and six. The results describe that student´s understanding for photosynthesis and the carbondioxids function for photosynthesis doesn´t change significantly from grade four to grade six. I have divided the students inte three levels based on their understandingof the various fields, and their use of adequate concepts.
Alice Springs drivet av solenergi - En jämförelse mellan solceller och Stirlingsystem
In the middle of Australia there is a city called Alice Springs. The city has one of the highest amounts of daily sunshine hours and sun irradiation in the world. The Australian Government runs a project called Solar Cities, and Alice Springs is one of the participators. The main part of the goal with the Solar Cities project is to increase the amount of electricity generated by solar power and by doing that lower the impact on the environment. This thesis examines the possibilities for construction of a large scale solar power plant in Alice Springs. This is done to determine the potential of creating a more sustainable energy system in the city.
Alternativ uppvärmning av reningsverket på Utö - En studie av energibesparingsmöjligheterna i syfte att minska uppvärmningskostnaderna
The projects objective is to find an alternative method of heating (the current method being via electric heating) the sewage treatment plant on the island Utö in Stockholm?s archipelago in order to reduce the energy consumption and ultimately the cost for heating the plant. The project is given by ?Skärgårdsstiftelsen? (The Archipelago Foundation) and is a part of the larger EU-project ?Green Islands?.A model for the plants total heating demand is established in order to get a good perception of how much money can be saved using alternative heating methods. The heating demand model gives an annual heating demand of approximately 32 500 kWh and a maximum heating power demand of around 24,7 kW.
Konstruktion och reglering av flygande plattform
This report describes the manufacture and control of a flying platform. The report describes the basic and fundamental theories required to get the platform flying. It touches on subjects such as A/D-conversion. PWM-control and PID-control. The sensors used in the platform are a gyro and an accelerometer.
Användning av accelerometrar för detektering av rörelse i Husqvarna ABs gräsklippare Automower
In order to detect movements and vibrations on different appliance, especially robots and self-going devices are used different sensors. One of the most used movement sensors are accelerometers. They are three different types of accelerometers one-axes, two-axes and three-axes. They can be analogue or digital. Husqvarna AB uses an accelerometer to detect movements of their self-going lawnmower Automower.
Kapitalandelslån : ? Ur ett bolagsra?ttsligt, skattera?ttsligt och redovisningsra?ttsligt perspektiv
This is a qualitative case study of young womens? experiences of blogging about One Direction on the social media/microblogging platform Tumblr. The aim of this study was to find out what fan blogging is and why fans blog. We did this by creating an account on Tumblr where we invited young women between the ages of 16?29, who had active fan blogs dedicated to One Direction, to answer an open-ended questionnaire.
Utveckling av en metodik för att med hjälp av lagerföljdsdata och geografiska informationssystem (GIS) modellera och rekonstruera våtmarker i Skåne
Syftet med detta arbete är att, med hjälp av GIS och lagerföljdsdata, utforma en metodik för modellering och förståelse av våtmarker och deras utbredning. Metodiken ska, med hjälp av GIS, underlätta och förbereda för en mera automatiserad analys av lagerföljdsdata. Detta involverar flera steg: (1) Strukturering och urval av relevanta data utifrån en stor mängd geografisk och geologisk information; (2) framtagning av åldersmodeller utifrån daterade borrkärnor för beräkning av tillväxthastighet hos olika jordarter; (3) Utveckling och implementering av ett datorprogram för beräkning av våtmarksnivå vid olika tidssteg. Beräkningen skall baseras på de, utifrån åldersmodellerna, beräknade tillväxthastigheterna för jordarter i olika borrkärnor; (4) Interpolation av framräknade höjdvärden till kontinuerliga ytor där förändring av våtmarkernas area och volym vid olika tidpunkter kan bestämmas. I denna studie beräknades utbredningen för två våtmarker vid tiderna 0, 1000, 2000 och 6000 år sedan.
Konceptarbete om skidbalk i kompositutförande till BVS10
This thesis has been performed at BAE Systems Hägglunds, which is located in Örnsköldsvik. Hägglunds has a wide background of engineering, where they have manufactured all from airplanes to lifting cranes. Currently they only produce track vehicles at Hägglunds, where they manufacture the CV90 and BVS10 models. This thesis concerns the BVS10 which is an all-terrain-vehicle. The main purpose with the BVS10 is to enable transportation of material and personnel thru tough terrain.
Visualisering och beräkning av hudkapillärer
The aim of this thesis was to develop an objective and automatic method for identifying capillaries in microscope images of the skin. Furthermore, statistical data about the identified capillaries and the capillary distribution should be computed and stored in a database. The method was implemented using the platform independent programming language Java. An analysis of microscope improvement using various polarization filter setups and wavelength filtershas also been performed, as well as a pilot study of the effect of applying a local anaesthetic cream on the skin. The method is developed and aimed at research on various pathological skin conditions affecting the capillary distribution.
Konstruktion av upprätningssystem för CICLoPE
Today there is no way of measuring or simulating turbulent flow in high Reynolds numberenvironments. The computational power required to simulate these conditions is not expectedto be available for several decades so instead the CICLoPE project aims at solving thisshortage by the construction of a long carbon fiber wind tunnel in which real measurementscan be made. To do accurate measurements it is of importance that the wind tunnel, 0.9 metersin diameter and 110 meters long, is as straight as possible.This master thesis treat the design and construction of a device which may be used to align thetunnel along a reference laser beam. A design is presented which allows the pipe to be alignedwithin about a quarter of a millimeter along its entire length. Contents span over severalscience fields such as physics, mechanics, control theory and electronics.The result is a theoretically correct design.
Utvärdering och konstruktion av SVIA:s standardmaskin FeedLine
This report describes an bachelor thesis work which is performed in cooperation with SVIA that develops and sells automation solutions for the manufacturing industry. The thesis purpose was to evaluate the machine FeedLine to find opportunities for improvement in the product?s design that could lead to more standardization and thus improving the efficiency of manufacturing and assembly.Based on these basic issues suggestions for improvements were developed:How can the design of FeedLine be improved to facilitate the assembly?Can more standardization be imposed on FeedLine?s design to enable more stocking of standard components?An initial pre-study was conducted to evaluate FeedLine?s to find opportunities for improvement in its overall design. During the pre-study staff at SVIA and two of its clients was interviewed. Based on information gathered during the interviews and observations by the authors improvements was amendments.