Tappningsstrategin för Vänern ändrades i ett beslut från Länsstyrelsen i Västra Götalands län och Vattenfall AB, på uppdrag av regeringen år 2008. Detta gjordes för att minska risken för översvämningar i Vänern.  Åtgärden var föreslagen av Klimat- och sårbarhetsutredningen, som försökt utreda konsekvenser av klimatförändringar för Vänern i ett framtida förändrat klimat. I utredningen används en metod för att mäta kostnader. Metoden är en kostnads-nytto-analys (Cost-Benefit-Analysis; CBA) som användes för att utvärdera bland annat Vänern med omnejd. Enligt denna uppsats saknas det värdering för naturmiljö och sociala faktorer i denna utredning.

Large companies in today?s business environment are to a great extent depending on their credit score by rating institutes like Moody?s and Standard & Poor?s. There is however indications that these big institutes are not always rating companies accurately. This is why this thesis aims at developing a new credit rating model, CRITA-Score, with the objective of determining a company?s financial health more accurately.

Aquatic organisms are usually not exposed to single substances but rather to mixtures of toxicants in streams located in agricultural areas. The transport of pesticides used in the agricultural area in Sweden is monitored with continuous environmental supervision every year. During 2002-2008 an average of 10 pesticides were found in each sample and 40% of the samples contained substances with concentrations higher than the Water Quality Standards. Chemical risk management is normally based on single-test evaluations. A problem when assessing mixture toxicities is that the constituents and concentrations of pollutants in the environment vary greatly.

Today most ice rinks in Sweden use secondary refrigeration systems with a solution of calcium chloride and water as secondary refrigerant. Due to the large amount of energy such a system uses more efficient systems would be desired.An earlier study concluded in the possibilities of using carbon dioxide as secondary refrigerant with copper tubes as the loops in the ice rink. Since then 3 ice rink refrigeration systems has been built with carbon dioxide in copper tubes. Excluding the ones being direct involved in those projects there is still very little knowledge about how these system works. This study has been made primarily with the aim of adding to the knowledge concerning availability and cost and secondary to look at possibilities for improvement.A comparison between systems with carbon dioxide, calcium chloride respective ammonium solved in water has been made by using Decision Matrix.

Svenska Kraftnät is (together with the other transmission system operators of the Nordic power system) responsible for keeping balance between the generated and demanded power in the Nordic power system. Spontaneous load variations and system disturbances, however, lead to power imbalance followed by frequency variations. The frequency deviations can be limited to an acceptable level by the spinning reserve, mainly by hydro power control. But there are also other system properties which have a great influence on the frequency and system stability. The frequency and voltage dependence of the loads have a direct influence on the power balance.

In coastal wetlands carbon/organic matter can be stored for long periods of time thanks to, among other things, the presence of water which slows down the decomposition. Because of this, restauration and management of such habitats have the potential to decrease the emission of greenhouse gasses and help mitigate climate. Internationally these environments are called ?blue carbon? ecosystems. In Sweden, alder (Alnus glutinosa and Alnus incanata) covered wetlands along the coast is a nature type that potentially could function as a ?blue carbon? habitat.

Environmental destruction is a growing problem in our world. Almost every day there are new reports concerning that we have to do something about the greenhouse gasses. Simultaneously is the human constantly more eager to have a life with higher standards and therefore uses more energy. The environment is a question that is highly up-to-date and more people try to find solutions on how to save our planet. One way to decrease the energy demand is to build passive houses, where the houses don?t have any active heating.

The harbour in Arvika is closed down and the industry that has been established in the area is now beeing wound up. A deepened comprehensive plan for the area is under progress in the municipality. The intentions are for instance that the harbour should be integrated with the city and that Arvika is facing a lake should be more apparent from the city center. The harbour should also contribute to a more attractive city. These intentions have hence been the starting point of my undergraduate theses, which has resulted in a proposal on how to develop the harbour. During the process I have analysed the city image, how the area is used today and the public places in the city centre.

The purpose of the house which is the basis of this report is to be able present itself on the market as a relatively cheap and at the same time a climate friendly choice. The house is supposed to be able to be built anywhere in Sweden and the rest of Scandinavia in a short period of time. This puts demand on what kind of heating system the house can have, since not all places have the geographic advantage of being able to use geothermal or district heating. Therefore the heating system choices will only include those that are not limited by their geographic location. The house will be built in modules which only require the groundwork to be done before the house can be erected. In this report "System solutions for plus or passive-housing" a comprehensive literature search has been conducted as well as a number of calculations.

A power system will inevitably be subjected to transient overvoltages, most often produced by switching operations and lightning strikes. These transient overvoltages may harm sensitive equipment without sufficient protection, but it is not an easy task to predict what transients may occur or how they affect the system. A fault occurred in a low voltage system at Forsmark 2012 and overvoltages from lightning were concluded as the probable cause. The three aims with this thesis are to develop and test a model of the power system at Forsmark 3, analyse the transient behaviour of the system when subjected to lightning surges and identify critical parameters, and lastly to provide a tool for investigating the protection of the system. The modelling and simulations were performed in the freely available simulation program LT Spice.

Syftet med studien är att undersöka varsels effekter för företags effektivitet och produktivitet under lågkonjunktur. Vår studie bygger på intervjuer med både chefer och anställda från företaget Water Jet Sweden AB. Studiens resultat är att personal påverkas av företags beslut om varsel om uppsägning genom att arbeta mindre effektivt. Detta är så för att varslet sänker arbetsmotivationen och tryggheten vilket gör att personalen underpresterar, detta påverkar hela företaget negativt..

Transformation of inorganic mercury (Hg) to methyl mercury (MeHg) is a biotic process that is proposed to be conducted primarily by sulphate reducing bacteria (SRB). The formation of MeHg is of great interest because it is the mercury species that biomagnifies to the greatest extent in the aquatic food webs; about 90 % of all Hg in fish is MeHg. Our understanding of factors involved in the production of MeHg is very important for making a reliable risk assessment. The purposes of this study were to investigate the different factors that control the solubility of Hg and the production of MeHg in a contaminated lake sediment. The lake Ala-Lombolo, Kiruna municipality, is well-known to be contaminated by mercury from different sources. Sediment cores were sampled at three different locations (N, SW and SE) in the lake and divided in three different layers; 0-5, 5-10 and 10-15 cm.

This study examines how the local rescue services relate to the brand of the rescue service and the concept of brand management. To understand the attitudes against the brand and brand management, empirical data, theoretical modelling of brand and current laws have been discussed together in a try to get an overview how the rescue services practically works with the brand. The study results are based on a questionnaire survey and qualitative semi-structured interviews. The survey was sent to employees working with the communication of the rescue service. The interviews were held with two employees working with the communication of the rescue service and two fire chiefs.

Several studies have analysed the relationship between Normalised DifferenceVegetation Index (NDVI) and radiative surface temperature. A main goal for moststudies have been to find the best method for carrying out land cover classificationsand to study land cover changes, based on a combination between the twoparameters. Since atmospheric components have a significant influence on bothparameters, most applications were based on multi-temporal data. The quality of theindividual values in such a combination is improved, but the biophysical justificationis uncertain. This study presents a different method, based on only the combination ofvalues that have been registered the same day and about the same time of the day.125 daily images of NDVI and 250 images of radiometric temperature were used inorder to analyse the relationship between (1) NDVI and radiative temperature and (2)NDVI and relative temperature difference between early morning and mid-day.Results between NDVI and radiative temperature show a significant negativecorrelation on areas where a distinct growing season develops, and a strong positivcorrelation where vegetation is abscent throghout the season.

Aquaponics is a food production system consisting of a consecutive cultivation of plants and aquatic animals, fish or shellfish, in recirculating water. The plants feed on the nutritious effluents from the fish tank and bacteria converts ammonia from the fish tank into nitrate that is absorbed by the plants. The plants receive nutrition and the fish gain purified water. The environmental impact of the production of fish meal and fish oil used in conventional fish feed includes a large consumption of fossil fuels with subsequent carbon dioxide emission. The aquaponic system can be made environmentally sustainable and self-supporting if supplemented with a vermicompost/vermiculture for the production of worm protein as a fish feed. Vegetable waste from the hydroponic part of the system can be reused as worm feed in the compost and the protein rich worms can be harvested, dried and grinded and brought back to the aquaculture as fish feed. As a first step in this direction, I have investigated the effect of recycling of vegetable waste in vermicomposts on the growth and number of earthworms (this was evaluated after harvesting). The hypotheses were that earthworms can be cultivated in the vegetable waste and that by adding manure to the vermicompost it is possible to obtain a nutrient content adequate to support a continuous worm harvest, in other words create a vermiculture. Eisenia fetida and Dendrobaena veneta were grown in 20 L bins containing peat mixed with either poultry or cattle manure. The proportions were 70% peat and 30 % manure. Discarded plant parts from lettuce cultivation was added to the vermicomposts (35 g per week) and water was supplied with 0.8 L per week.