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1616 Uppsatser om Surface water - Sida 21 av 108

Naturlig förekomst av arsenik och avskiljning av arsenik från grundvatten : test av olika filtertekniker avsedda för enskilda brunnar

During the last few years the presence of high arsenic (As) concentrations in ground water has been of major concern both internationally and in Sweden. Much evidence has been reported about toxic effects caused by arsenic. The carcinogenic effects and the possibility to measure the toxic impacts at low concentrations made the World Health Organisation (WHO) to reduce the guideline value from 50 to 10 ?g l-1 in 1993. In Sweden the corresponding reduction was implemented in 2003. Several surveys in Sweden have shown that high arsenic concentrations may occur in ground water.

Bestämning av dagvattenflöden i Knivstaåns avrinningsområde

The purpose of the thesis was to map the hydraulic load on the Knivsta river from stormwater runoff, and build a platform for further studies of pollution loads on the rivers ecosystems. New residential areas are planned to be built in Knivsta municipality and it will have an impact on stormwater flows to Knivsta river. To examine the impact this will have, simulations were made in the area as it stands today and after expansion work. The work includes calculation of flows from the populated areas but also from the catchment area around it consisting of woodlands and fields. Because of expected climatic changes which may affect rainfall, the simulations have been performed with different return periods for rainfall data.

Majstorkning :

The corn plant came to Europe with Christopher Columbus in the 14th century and have ever since bin cropped here, but corn haven?t bin very common in Scandinavia until recently. The mainly use for this crop silage but even corn for grain is cropped in Europe. Corn for grain is a common part of feed in beef and chicken farming. In Sweden corn for grain is pretty rare but almost 1000 hectares are used for this crop, Lantmännen Sverige is the biggest buyer of corn at the moment.

LCA av dricksvattendesinfektion : en jämförelse av klor och UV-ljus

Disinfection methods for drinking-water produced at the two water works of Stockholm Water Co are compared in this study. Three different nethods are compared; disinfection with chlorine gas, disinfection with sodium hypochlorite and disinfection with UV-light and monochloramine. The method used is Life cycle assessment, LCA. LCA is defined as the compilation and evaluation of the inputs, outputs and potential environmental impact of a product system shroughout its life cycle. The environmental burden is compared for the three different disinfection methods.

Förstudie för skapandet av ett miljöövervakningsprogram : en styrkeanalys angående vattendrag i västerhavets vattendistrikt för fastställandet av provantal i tid och rum för ett effektivt omdrevsprogram

The environmental monitoring in Sweden has been developed by several different parties and is now being coordinated and made more effective in order to meet the current demands on high quality information regarding the state of the environment. Sweden has been divided into five different water districts based on watershed areas because of requirements in the Water Directive of the EU. In Sweden there are two common types of environmental monitoring programs used to gather information on changes in time and in space. Currently both these two types are used for lakes in the water district of the western sea but only one is used for watersheds. The purpose of this report is to supply basic information regarding the possible need for a second environmental monitoring program for watersheds in order to better describe the spatial variation within the district as well as to determine the number of samples necessary in order to describe the district over time and space.

Bakteriell produktion i humösa istäckta sjöar i norra Sverige

The main purposes of this study were to 1) quantify bacterial production in winter during ice conditions, and 2) to compare these production measures with values measured from summer and open water conditions in three humic lakes situated in northern Sweden. Another purpose of this study was to 3) examine whether clear-cutting significantly affected bacterial production or water chemistry in two lakes situated in catchments were a large part of the forest had been removed through logging compared to an undisturbed reference lake. In winter (March/April 2014), the bacterial production ranged from 0, 7 - 2, 2 µgC/L/day and in the summer of 2013 the production values was 4 ? 10 times higher. The main reason for lower bacterial production in winter was ascribed to lower water temperatures as well as to older and more recalcitrant DOC, as there were no significant differences in total dissolved nitrogen or DOC concentration or -quality, that could explain a lower production compared to summer.

Jämförelse av algoritmer för polygonisering utav volymetrisk data

Digitala spel har länge använt sig av terräng, det vanligaste sättet att lagra dessa terränger är med så kallade höjdkartor. Höjdkartor har en stor begränsning, de inte kan innehålla tunnlar.Denna rapport undersöker två alternativ till höjdkartor som arbetar med voxlar. Dessa två algoritmer är Marching Cubes (Lorensen & Cline, 1987) och Constrained Elastic Surface Nets (Gibson, 1998). Syftet med undersökningen är att evaluera dessa algoritmer med avseende på tidseffektivitet, minneseffektivitet och visuell korrekthet för att ta reda på vilken algoritm som öveträffar den andra med avseende på vilken aspekt.De utförda experimenten visade att Marching Cubes (Lorensen & Cline, 1987) var den mest tidseffektiva av de två, Constrained Elastic Surface Nets (Gibson, 1998) var mest minneseffektiv och Marching Cubes (Lorensen & Cline, 1987) var mest visuellt korrekt. Vidare forskning i ämnet skulle kunna göras på terränger som är för stora för enskilda modeller..

Naturlig haptisk kraftåterkoppling från volymdata

As the volumes are entering the world of computer graphics the pure volume visualisation becomes a more important tool in for example research and medical applications. But the advance in haptics --- force feedback from the computer --- is behind. In volume haptics no equal to the proxy method so popular in surface haptics has yet emerged. Some implementations of volume haptics even use surfaces as intermediate representations so that surface haptics can be used.The intention of this work was to create natural feeling haptic feedback from volumetric density data using pure volume haptics. The haptic algorithm would be implemented in Reachin API for the Reachin Desktop Display, together with other parts to build up a usable volume visualisation environment.To achieve the feeling of stiffness and friction dependent on tissue type, a proxy based method was developed.

Jordbruk och mjölkproduktion med kor i Etiopien :

Ethiopia is the country with most livestock per capita on the continent of Africa. There are 34.5 million cattle that are used for drought, meat- and milkproduction and 85% of the population rely on agriculture for their survival in some way. Milk is produced in four main systems, through pastoralism in the lowlands, in mixed crop-livestock systems in the highlands, in and near big cities with only one or two cows, and in intensive farming systems. There are 17 cattle breeds in Ethiopia and some of them are more suitable for milk production than others. Several environmental and economic problems arise from livestock holding in the country, for example overgrazing, low production due to feed shortage, low quality of the avaible feed and non-existing breeding programs.

Jämförelse av effekter från gruppträning i bassäng med landträning hos patienter med knäartros : Utvärdering av effekter på smärta, funktion i det dagliga livet och fritid- och idrottsaktiviteter

AbstractAimThe aim of the pilot study was to compare short- and long-term effects from group exercise in water with land-based exercise on pain at rest and pain with movement, along with the effects on function in daily life and practice of sports and leisure activities in patients with knee osteoarthritis. The aims were: Is there a difference in short- and long-term effects on pain intensity at rest and pain with movement after exercise in water or land in patients with knee osteoarthritis? Is there a correlation between the degree of pain intensity at rest and with movement, respectively and long-term effects from the two different exercises on function in daily life and practice of sports and leisure? MethodThe study was a randomized intervention study without a control group. Twenty patients with radiographic knee osteoarthritis were under a total of eight weeks treated with either land- or water-based exercise lead by a physiotherapist. The patients rated pain intensity at rest and with movement on a numerical rating scale (NRS) before and after the first training session, before and after the eighth training session, before and after the fifteenth training session and before the last and sixteenth training session.

Konceptframtagning av testinstrument för vattendetektion baserad på MIP

Water is vital for all life on earth. But it can also be dangerous, even fatal, if it is polluted water. 60 percent of child mortality can directly be deduced to dirty water. Not only developing countries are affected, even in the western world epidemics are breaking out by partake or bathing in dirty/polluted water.MIP, Molecularly Imprinted Polymers, is a biosensor technology that can provide faster and more reliable response than the current methods of water analysis. It is also cheaper and due to that more samples can be taken and analyzed.

Fuktskador i ytterväggar på grund av vattenintrång

Moisture damage in buildings is a serious issue that leads to problematic consequences and high economic costs. Despite the knowledge and awareness existing about moisture problems, extensive damager still occurs today. Studies of moisture in the exterior wall constructions shows that the issue if often caused by rain and water intrusion. These kinds of problem result in major costs usually because the companies have to replace the material and structural components and also in some cases tear down large parts of the buildings.The work includes moisture theory and descriptions of four different exterior wall constructions, wood stud wall with plastered facade, exterior wall with wood facade, exterior wall with concrete, and exterior wall with brick facade. Our thesis work describes how the constructions are affected and moisture damage due to water intrusion.

Rening av metallhaltigt avloppsvatten : En teknisk/ekonomisk utvärdering av reningsmetoder för metallhaltigt avloppsvatten

This Master?s Thesis aims to investigate and assess the methods used to decrease the discharge ofmetals, primarily copper, from the water purification plant at Assa Industries plating factory inEskilstuna.Literature studies of the purification methods precipitation, ion exchange, evaporation, reverseosmosis and electrolysis has been done to appraise the adequacy of the technique. Thesetechniques are commonly used for purification of industrial waste water.Assa has four plating lines: the Trumline, the big Zinkline, the new Zinkline and the Decorativeline. The new Zinkline is the most modern of the four lines and purification is done byrecirculation over an ion exchange unit. The demand for fresh water is thereby heavily reduced.The Trumline, the big Zinkline and the Decorative line all use older techniques.

Analys av meningsskapandet i Hannah Ho?chs fotomontage Schnitt mit dem ku?chenmesser Dada durch die letzte weimaren bierbauchkulturepoche Deutschlands

This paper examines Hannah Ho?chs photomontage Schnitt mit dem Ku?chenmesser Dada durch die letzte weimaren bierbauchkulturepoche Deutschlands. The paper has as its aims to understand and analyze the predominated allegorical interpretation of Schnitt and to develop a logic how meaning is produced when a viewer look at Schnitts surface. The paper finds that the predominated interpretation has been arbitrarily created out of a specific spectator that acts in a specific context and conclude instead that the predominated interpretation should be understood as a potential interpretation by a potential viewer. The paper continues to create an understanding of Schnitt as a flatbed picture to establish that as a postulate and to use it in the later semiotic dissection of Schnitts surface.

Kartläggning av föroreningars förekomst och spridning i Gräsötippen enligt MIFO

It is estimated that 22 000 contaminated areas exist in Sweden today. In order to classify the risk of contaminant migration from these areas and to prioritize which of these contaminated areas should first be treated, the Swedish Environmental Protection Agency (EPA) has designed a method, for the investigation of contaminated areas (MIFO). One of these contaminated areas is the landfill Gräsötippen outside Köping. The landfill has been used by both Yara AB and the Köping municipality between the years 1945 and 1975, and both industrial and household waste have been deposited there. The aim of this report is to survey which contaminants that can be found in the soil and water in the landfill Gräsötippen and to evaluate the migration of these contaminants.

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