The agricultural sector is currently highly dependent on fossil fuels, with diesel beingmost prominent. There are however both historical and modern alternatives thathave not been subject to enough evaluation to disregard them as suitable alternative.This report aims to theoretically investigate the feasibility of converting aconventional diesel driven tractor to run on electricity, delivered via a cableconnected to either the main power grid or on-site electric production, such asphotovoltaic. Delivering electricity to the machine via a cable is a method withhistorical roots in the early 20th century and in the present day mining industry.The economic and technological potential of the technique are evaluated, along withthe examination of several different motor powers, voltages, losses and constructionideas. The report finds the technique to be both possible as well as long termeconomically and environmentally beneficial. To realise this method however, somedeviations from the present methods of agricultural farming must be made,considering the more advanced driving patterns, the limited mobility and therequirement for extra driver awareness.

The assignment given to us by NCC was to compose a degree project based on ground excavations for power cables. The aim of the study was to examine suitable excavation methods depending on different possible terrain conditions. The amount of previously written material within this subject is nearly non- existent and therefore there is a genuine interest by the NCC to receive a compilation of different production methods. The greater part of this study is based upon interviews with several companies active within this area of expertise. The technique of placing the electricity grid beneath ground for safety is today getting more and more common.

This essay deals with risk management and social risks, which have received increased attentionin recent years. Methods for dealing with social risks, for example within local Risk andvulnerability assessment (RSA), are currently under development. The purpose of this paper is toexamine if and how social risk can be quantitatively assessed and mapped using GeographicInformation Systems (GIS). The definition of social risk that the essay is based on states: "Theprobability of unwanted events, behaviors or conditions originating in the social conditions thathave a negative impact on the objects that are worth to preserve.? A number of social riskindicators that can be used for a spatial analysis have been operationalized based on thisdefinition.

The objective of the thesis is primarily to conform and encode a digital signal to be controlled by software. The idea is to transport today?s tracesignal through the IP-network instead of cable-net. In this report I will suggest a possible solution to get a fully passed result with no peculiar time delay. I will also suggest some ideas for a future work with the new tracesystem..

The assignment is issued by Scania Maintence AB seeking a new approach to detect power changes in their industrial processes. The work has taken place at Ångströmslaboratoriet and tests have been performed at Scania AB Södertälje.Today?s society consumes enormous amount of energy. In both economically and environmental view, it is important that the processes are effective, with high power factor. There are many ways to measure power in the industry, what they all have in common is that the installation is advanced, requires time and planning.

Not much is today known about how epiphytic lichens are effected by fire. A considerable part of the fires in Sweden today are prescribed fires for the purpose of environmental conservation. How these fires affect lichens is largely unknown. The aim of this study is to find out how epiphytic fruticose and foliose lichens on Scots pine are affected by fire, and to elucidate the relationship between fire intensity and the survival of lichens and later re-colonization. The study was performed at three locations just outside Umeå in Västerbotten that were burned 5-7 years earlier. In all locations there were larger groups of surviving Scots pines with varying amount of fire-damage in the crown, which enabled a reconstruction of fire intensity.

Not much is today known about how epiphytic lichens are effected by fire. A considerable part of the fires in Sweden today are prescribed fires for the purpose of environmental conservation. How these fires affect lichens is largely unknown. The aim of this study is to find out how epiphytic fruticose and foliose lichens on Scots pine are affected by fire, and to elucidate the relationship between fire intensity and the survival of lichens and later re-colonization. The study was performed at three locations just outside Umeå in Västerbotten that were burned 5-7 years earlier. In all locations there were larger groups of surviving Scots pines with varying amount of fire-damage in the crown, which enabled a reconstruction of fire intensity.

Sweden recently changed the national regulation of chimney sweeping. This study has two purposes. The first purpose is to evaluate the effect of this reform to see if the new regulation has led to an effect in terms of increased chimney fires in single-family houses and for the wood-burning and oil-burning stoves, respectively. The second purpose is an updating of a previous study (Mattsson 1994) of analysis of society´s benefits and costs of different alternative sweeping frequencies for wood-burning and oil-burning stoves. This study also has a secondary purpose to examine the extent to which the local sweeping rules vary with climate conditions.  Mattsson, based on his results, proposed that the sweeping requirements for oil-burning stoves should be reduced from twice a year to once every second year and for wood-burning stoves the sweeping should be reduced from four times to once each year.

The last century, forest fires have decreased in frequency due to efficient fire-suppression along with the growth of the industrial forestry. Since 1990, fire has been reintroduced under controlled forms to recreate burnt habitats. Many species that are dependent on, or benefits from, forest fires have increased since fire was reintroduced. The importance of connectivity is often addressed in ecological research. This is particularly important for species dependent on short-lived habitats such as burnt forests.

Analyses of pollen and charcoal in peat cores, together with age-structure data of Pinus sylvestris from a Ledum-Pinus-mire in the Tyresta National Park (south-east Sweden) show the regional vegetation succession and fire history over the last 9000 years. Five major stages of mire development are identified: 1. Lake (c 7000-6400 cal BC); 2. Wet fen (c 6400-6000 cal BC); 3. Deciduous fen (c 6000 cal BC to c cal AD 700); 4.

The global biodiversity loss is mainly due to human activities such as an intensification of forestry. Boreal forest ecosystems in Fennoscandia are characterized by disturbances such as forest fires, storms and floods. However, industrial forestry practices suppress forest fires and change the landscape, leading to a loss of habitats and associated species. Particularly lichen species with slow adaptation abilities and a strong substrate specificity face an extinction debt in boreal forests since their substrates are long-lived but no longer created. In this study the species-substrate relationship of two red-listed forest-fire dependent lichen species Carbon-icola anthracophila and C.

When planning new wind farms, the cost for the internal electrical grid is estimated to account for 8-9 % of the total investment cost. On top of that, the cost for accumulated reduced income over several years (due to electrical losses), has to be added. The economic lifespan is relatively long (about 20 years) which means that an error in the loss calculation could lead to a bad decision basis. The accumulated reduced incomes due to electrical losses can be higher than the initial investment cost for the internal electrical grid.Today, Statkraft Sweden is using a template number when estimating the electrical losses in a wind farm. The actual losses are probably lower than the template number which could lead to an unnecessary high loss cost when planning a new wind farm.The aim of this M.Sc.

This report tested the possibility of using induction as a mean for transferring data and power so that it can be implemented as a communication medium between a terminal and measuring head mounted in a measuring frame. This would eliminate the need for the cable bunches that are used today. For testing, signal generators were used to generateFSK-signals and were transferred with the help of inductors to the oscilloscope for signal detection, this to see how the coils used in the tests behaved. Simulations of a PLL were performed to see how good it could handle FSK-demodulation. With the help of a PLL IC and the simulations a working FSK-demodulator could be assembled.

In this work I have tried to reconstruct the forest history within Särna-Idre forest common in northern Dalarna from the 19th century until present time. The Särna-Idre region has been an extensively used landscape for a long time. Pollen which indicates grazing has been found in samples orginating from the 10th century. Early travellers from the 18th and 19th centuries seem to have been passing trough a "used" landscape. Burned forests on naked ground are described as common. Also large areas are mentioned as undisturbed with lots of large trees, snags and dead wood.

The objective of this study was to examine how an IT department has been affected by the changes of increased local usage of IT, and how the usage have affected municipalities IT departments demands of IT support. In the study we explore how both the IT department and the IT support works by interviewing present and former employees at the local IT department. The current IT department have undergone a series of local changes over the last 20 years, the department has gone from only having internal users to getting the entire municipalitiy?s agencies of IT as users. It started with how the municipality began to dig down fiber optic cable in the middle of the 1990?s, and today has started to develop solutions as to how to meet the demands of future usage of IT.