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1298 Uppsatser om Water scarcity - Sida 20 av 87

Konstruktion av testrigg för moderna ångexpandrar

This report summarize what have been done during the Master of Science Thesis that Klas Schjelderup has written for the company RANOTOR Utvecklings AB. The company is developing modern steam engines and this work should develop a machine to perform tests on a new type of piston seal that hopefully could be used in the future. The steam engines will be both volumetric and energy compact, around 1600hp/literof cylinder volume, and it will have a lot of practical applications.The new type of piston seal is hydrostatic lubricated which means that a fluid is separating two faces that normally is in contact. In this case pressurized water is used to separate the piston seal from the cylinder wall. RANOTOR have earlier formulated that at least the expander in the modern steam engine have to be oil-free, due to other components functionality in the closed water system.

Francisella tularensis subspecies holarctica : the curious case of a water- and mosquito associated bacterium in Sweden

Francisella tularensis, the causative agent of the zoonotic disease tularaemia, is highly contagious and potentially fatal for a wide range of wildlife species of the northern hemisphere, also humans. Although recognized as a pathogen for over 100 years, much still remains to be elucidated concerning the ecology and transmission of the bacterium, hence this literature overview aims at compiling data regarding the aquatic association and the role of mosquitoes in transmission of Francisella tularensis subspecies holartica, the sole subspecies in Sweden. While a linkage between the bacterium and natural waters stands beyond dispute, there is no consensus in the literature concerning its potential as a reservoir. However, two prevailing theories can be distinguished; one proposes the water association being mammaldependent and thus merely the result of contamination from semi-aquatic mammals living in close vicinity to the water source. The other, quite contrary, suggests mammal-independence and hence that water, possibly in association with protozoa, serves as an environmental reservoir for the bacterium.

Utveckling av kyl- och smörjsystem för ekobilen Agilis HCCI motor

Every year, KTH participates in the Shell Eco Marathon, a competition whose goal is to design a vehicle that can go as far as possible using only the equivalent energy of one liter of petrol fuel. This year, one of KTH?s contributions to this race is the Agilis prototype; a car powered by a uniquely configured HCCI-engine developed at the university. The engine is dependent of several subsystems in order to work properly, among other, systems for cooling and lubrication.Combustion engines are in need of a cooling system that reduces the heat developed during the combustion. In general, two main types of cooling systems are employed; either air cooling, where the outside of the cylinder is exposed to a flow of the surrounding air, ore water cooling, where water flows in tubes around the engine, and the heat are transferred by the water to the surrounding air through a heat exchanger.The purpose of the lubrication system is to prevent the friction that builds up in the interference between moving parts in the engine.

Gemensamberedningen av EU:s Maritima Grönbok ur ett Resiliensperspektiv : En studie om den adaptiva kapaciteten i Regeringskansliets inre processer

The study aims to give a description of the conditions in which matters is prepared withinSwedish Government`s offices, to describe the adaptive capacity in the agency`s internalprocesses by investigating the experiences of some civil servants restricted to the Ministry ofEnterprise and the Ministry of Environment in their work with the EU Maritime Policy GreenPaper. The results have been analyzed against the basis of eight identified criteria of buildingadaptive capacity in socially dominated systems. The criteria are comprised of both individualand organizational abilities. Only two of them were fully met; the criteria about diversity inexperiences and knowledge and the criteria about information and how the information hasbeen applied. However, the process has traces of all the identified criteria.

Analys av artificiella marktyper vid vatten med hjälp av GIS, Värmlands län 2007

On commission of the County administrative board in Värmland County a method was developed for analysis of the occurrence of artificial land use at lakes and watercourses. With artificial land use is meant land significantly affected by man. Two bases have been used to carry out the analysis. In one of the analysis the vegetation database and in the other GSD¹-Marktäckedata (land cover data) was used (this method has been used by County administrative board in Jönköping County).The analysis comprises all watercourses within Alsterälven river basin. The digital water bodies are created by the Swedish Meteorological and Hydrological Institute on the basis of GSD-Översiktskartan (general map).

Energieffektivisering genom förvärmning av flis till kokare med sekundärvärme

The Swedish pulp and paper industry meets higher demand for energy efficiencyi mprovements with increasing energy prices and changes in the Swedish renewable energy certificate system. One action of energy efficiency improvement is by using secondary heat, that otherwise would have been treated as waste heat, for use in a system with lower temperature demands. The aim of this Master´s thesis is to identify possible secondary heat sources in a typical Swedish pulp and paper mill and to investigate what economic benefits the secondary heat will provide when being used for pre heating of wood chips to a kraft digester.The Master´s thesis focuses on three secondary heat sources; dry warm air, warm water and moisture saturated warm air located inside the pulp or paper mill. Two types of kraft digesters are simulated within this study, a typical Scandinavian digester and a modern twin vessel steam phase digester.Due to quality aspects and low temperature level drying is the drying technology with dry warm air rejected. Using warm water in direct contact with wood chips increases the quantity of water to the evaporation plant and thus reduced pulp or paper production and is therefore also rejected.

Risken för översvämningar vid de svenska kärnkraftverken : en statistisk och historisk extremvärdesanalys

This thesis investigates the overall risks of flooding over the Design Basis Flooding Level (DBFL) at the Swedish nuclear power plants (Oskarshamn, Ringhals and Forsmark), using statistical data and methods, but also considers historical events which might affect the overall risk of flooding at the specified sites.Considering the nuclear accident which happened in Fukushima in conjuction with the earthquake and tsunami which struck eastern Japan on 11 March 2011, operators and licensors of nuclear power plants all over the world conducted reviews and investigations on the overall risks posed to the plants from external events. One important such event is extreme water level.One part of the thesis includes an extreme value analysis (using Generalized Extreme Value distribution and Generalized Pareto distribution) of water level data from SMHI (Sweden's Meteorological and Hydrological Institute) measured at stations close to the Swedish nuclear power plants. The results of the statistical studies indicate that considering the return period used in the thesis (100 000 years), the water levels at the Swedish nuclear power plants are not expected to exceed DBFL.The other part of the thesis consists of a historical study of extreme weather-related events. The results of this study indicate that no historical events seem to have occured which would indicate a higher risk of flooding than the one suggested by the statistical study. .

Att Synliggöra det Osynliga : GIS som verktyg i sökandet  efter bosättningsområden från bronsåldern på Gotland

In this bachelor essay an attempt is done, to recreate a probable Bronze Age landscape on Gotland, with GIS as a tool. The landscape on Gotland is situated with many different monuments dated Bronze Age, such as cairns and stone ships. In creating of the maps, two possible shorelines contemporary with the Bronze Age have been calculated and marked on the maps. Furthermore, peat lands have been drawn upon the maps, by using the information from geological maps.A landscape variable have been compared between Bronze Age places and Early Iron Age houses; the soil type. On Bronze Age places gravel is the most common, while moraine marl is the most common on places with Early Iron Age houses.From a selection that were made, all Bronze Age places where within 3 km from the water, either the recreated shoreline or peat land.

En studie av sedimenttransport, död ved och kantzoner längs två vattendrag i Kilsbergen - från skog till slätt :

Headwater streams are affected by anthropogenic impacts at multiple scales. One aspect of human impact is sediment transport associated to the abundance of stream structures as large woody debris and the composition of the riparian zone from forest to agricultural landscapes. Riparian buffer zones and stream structures like dead wood are considered as generally important structures for protection against an increasing amount of sediment particles in the water. Hence, in this study these structures were quantified in thirty different stream segments on land and in the water. To measure the transport of sediment Whitlock-Vibert boxes were used in three different types of landscapes; forest, transition and fields. The boxes were left in the stream segments for three months, the taken up and dried and weighed. The results showed that the transition-land in Frösvidalsån had the highest sediment transport. The second highest transport of sediment was in Blackstaån at the fields.

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).

Biologiska behandlingsmetoder för rening av rejektvatten från biogasproduktion

In this literature review the characteristics of two free-floating macrophytes, water hyacinth   (Eichhornia crassipes) and duckweed (Lemna sp.), and two microalgae, Chlorella and Scenedesmus, have been examined regarding their suitability as efficient nutrient removers in the treatment of wastewater with high levels of nutrients and suspended solids from a biogas plant in Loudden. The needs required for the plants to be able to grow in wastewater and the amounts of biomass they can produce have also been studied. The results show that Chlorella is capable of a very high uptake of nutrients in photobioreactors with high nutrient loadings. With an ammonia uptake maximum value at 10900mg/m2/d Chlorella outshines the other organisms in this study. The test organism that performed the closest to Chlorella in terms of nitrogen uptake was water hyacinth with an uptake about 1602mg/m2/d.

Barnfattigdom 2012 : Ett levande problem i Uppsalas skolor

In this essay we aimed to find how economic scarcity among children and youth presents itself in school, according to how school staff experience it. We have conducted interviews with student welfare staff to hear their experiences of this subject and how the schools try to help these pupils. We have used interpretative phenomenology as a base for our work. We have also used some of this traditions most important notions along with notions of Erving Goffman and Sara Ahmed during our processing off the material.  With help from these, we report our most interesting results. We have seen that a lack of resources exists among youth today and that everyone not has easy access to things many of us might take for granted.

Tillämpning av en markprofilmodell för hydrologiska beräkningar i avrinningsområdesskala

There is a great need to reduce nutrient leaching from arable land into lakes and oceans. By using several different types of models it has previously been possible to describe nutrient losses in a catchment area with a minimum unit of sub-catchment level. At present, it is instead desirable to model a smaller catchment with an opportunity to re-connect the results to the corresponding fields in the catchment. Such models already exist but they are not fully able to properly describe Swedish conditions and land characteristics in our region.With the approach of creating such a model, SLU has developed a project with this work as its first stage. The model is expected to be created under the working name SWE-model which stands for Soil Water Environment and is in this first stage supposed to apply the SOIL model in catchment scale. During the procedure to describe the first step in the process of developing such a model adapted to Swedish conditions and which works in the catchment scale with an area of about 10-30 km2, focus has been set on calculating the transport of water flow from different hydrological response units. Regardless of the processes occurring in the soil after the water has been added, it is assumed that all the water which flows from each simulated unit is drained.In the first step the hydrologic response units were identified based on land use and soil type in the study area. With the help of a script with functions that retrieve and transform data, certain units were chosen for simulation. The script was also created in this project. Finally, the model results were aggregated and summarized for each unique unit, for each sub-catchment, and also for the whole catchment.From the results it is possible to see similarities in the flow dynamics between modeled and measured data. The efficiency coefficient has been calculated to correspond to the mean of the measured values for the whole simulation period. With an automated calibration process the model should be able to perform better. The volume error gives an indication of overestimation from the model..

Varbergs Societetspark 1856 - 2008 : en promenadparks förvandling

The Societety Park (Societetsparken) of Varberg here in Sweden, established in the year 1883 (1856), is one of the most famous parks in Varberg. Today it is, more or less, only used as a park that you will walk through in the wintertime, under the summer season though, the park starts blooming and then it is used for public music and singalong evenings. Earlier it was an old health resort park with its fine old traditions.The Societetsparken was a private owned park until 1902 when the town purchased it. On this plot there was already a smaller park and it was established as early as in 1856. It was called Badhusparken (The Public Bath Park) and it belonged to the hot- and cold-bathhouses, and these baths were very well frequented.

Energieffektivisering av skolbyggnad från 60-talet : Studie av Hållsta skola i Eskilstuna

In June 2006 the Swedish government decided that the use of energy in buildings should be reduced by 20 percent until 2020, compared to the level of energy used in 1995. To contribute to this goal, the real estate company ?Eskilstuna Kommunfastigheter AB?, set up own goals for their buildings. In 2009, the goal for schools was to have a maximum energy use of 118 kWh/m2year for heating and hot water.The school ?Hållsta skola?, just south of Eskilstuna, exceeds the limit since it used 270 kWh in 2008.

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