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1616 Uppsatser om Surface water - Sida 27 av 108

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.

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.

En validitetsstudie på beeptestet : avseende maximal aerob kapacitet för elitishockeyspelare

Introduction: This study aimed to investigate the validity and reliability of the 20m multistage shuttle run test (MST) for elite ice hockey players as a predictor of the maximal aerobic capacity and the how the result is affected by the players age, aerobic and anaerobic capacity, body composition and test surface. The purpose of this was to find out the potential of the 20-m shuttle run test as a measuringtool for the maximal aerobic capacity in frequent testing periods during the season. It is very interesting to be able to administer this easily because the competative phase of the season is very long compared to the pre-seasonal phase and earlier studies have shown that the aerobic capacity is being lowered during this competative phase of the season for elite icehockey players.Methods: 34 elite ice hockey players participated in this study (20.0±3.6 yrs, BMI 24.2±1.6 and VO2-max 58.0±4.8 ml O2?kg-1?min-1). During 3-5 days they underwent 2 MST tests (wood and rubber surface), treadmill running with VO2-max assessed with open-circuit technique, Wingate10% and FFM-assessment with underwater-technique.

Utveckling av en äldre villaträdgård : från oplanerad till planerad

The result of this work is a plan for the development of an 1128 m2 elderly raised garden. The purpose has been to create an overall plan covering the long-term development of the garden. The work process has covered a description of the garden of today, review of requirements, analysis of the garden sections, design of a new plan as well as starting the construction of the new garden. The plan covers a time period of a couple of years to create the new garden since the construction work is carried out during spare time with small resources available. The planning must contain review of functions such as protection from insight, eating area and compost area. Also the esthetic expression must be planned. Colors, shapes, choice of material and plants together make up the esthetic expression. It is recommended to include anything you wish to create in the garden. In a raised garden one has to overcome the step to remove trees and shrubs and think different.

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.

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.

Svartgran ? ett alternativ när allt ser mörkt ut? : en kartmodell för att visa lämpliga ståndorter för odling av svartgran

A common problem in forestry is plant death caused by frost. The risk of frost is highest on wind protected, flat or low-lying areas in the terrain. Here you often have regeneration problems with Norwegian spruce which is especially sensitive to spring frost. Swedish tree experiments have shown that the black spruce can be a suitable alternative on these areas, for example on moisture frost prone areas. The species originates from North America and its pioneer tree characteristics make it more frost hardy than Norwegian spruce.

Naturvärdesbedömning av Utanåfladen; En inventering av vårlekande fisk, bottenfauna och vegetation

There are several thousands shallow bays along the Swedish east coast. Most of them are disturbed by different human activities, and undisturbed bays can be considered as quite unique. In the sheltered shallow bays water warms up more rapidly than adjacent water favoring the growth of vegetation, which in turns is beneficial to spring spawning fish species like perch and pike. It is nowadays more common that coastal habitats are inventoried to facilitate future preservation and planning. The aim of this study was to investigate the shallow bay Utanåfladen (59° 53`31.38 N 19°00`44.90 E) in the north Stockholm archipelago and evaluate its habitat value.

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