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1582 Uppsatser om Soil water - Sida 13 av 106

Trafiksäkra vägar genom god vägutformning baserat på kunskap om det mänskliga beteendet - en utvärdering av metoden IST-Checklist 2005

Today more effective computer programs are in use, regarding design of geotechnicalconstructions. There is a risk that the theoretical background of the computerprograms, its limitations and the signification of the choice of soil parameter isforgotten when the computer programs become more user-friendly.This Master thesis deals with simulation and analysis regarding three computerprograms, FEM-design, with the addition Raft, Plaxis and BE-slab. Comparisons aremade for settlement and maximum moment in a concrete-plate. FEM-design is a threedimensional FEM-program, foremost created for design engineers. Plaxis is a twodimensional FEM-program, intended for geotechnical engineers while BE-Slab is aBoundary elements program in two dimensions that is mainly used by designengineers.

Samband mellan trafikolyckor och väggeometri. En analys av kopplade olycks- och vägdata för större vägar i Region Väst

Today more effective computer programs are in use, regarding design of geotechnicalconstructions. There is a risk that the theoretical background of the computerprograms, its limitations and the signification of the choice of soil parameter isforgotten when the computer programs become more user-friendly.This Master thesis deals with simulation and analysis regarding three computerprograms, FEM-design, with the addition Raft, Plaxis and BE-slab. Comparisons aremade for settlement and maximum moment in a concrete-plate. FEM-design is a threedimensional FEM-program, foremost created for design engineers. Plaxis is a twodimensional FEM-program, intended for geotechnical engineers while BE-Slab is aBoundary elements program in two dimensions that is mainly used by designengineers.

Buss eller spårvagn? Framtida kollektivtrafikförsörjning av området mellan Kungssten, Frölunda torg och Saltholmen i Göteborg

Today more effective computer programs are in use, regarding design of geotechnicalconstructions. There is a risk that the theoretical background of the computerprograms, its limitations and the signification of the choice of soil parameter isforgotten when the computer programs become more user-friendly.This Master thesis deals with simulation and analysis regarding three computerprograms, FEM-design, with the addition Raft, Plaxis and BE-slab. Comparisons aremade for settlement and maximum moment in a concrete-plate. FEM-design is a threedimensional FEM-program, foremost created for design engineers. Plaxis is a twodimensional FEM-program, intended for geotechnical engineers while BE-Slab is aBoundary elements program in two dimensions that is mainly used by designengineers.

Effects of biogas residues on respiration and denitrification in arable soil : evaluation of methods, microbial activity and agronomic implications

Agricultural soils constitute the base in human food production and soil content of organic matter and plant nutrients together with soil microbial activity are all important parameters for high crop yield of good quality. These parameters are dependant on proper fertilization.Anaerobic digestion of organic wastes for biogas production generates a liquid residue called biogas residue (BR). It contains organic material and plant nutrients which makes ita potential fertilizer for arable cropping. However, it also contains heavy metals and toxic organic compounds and it is therefore in need of evaluation before usage.Microbial tests were performed aiming to evaluate the agronomic traits of four different BR and to find a viable procedure for evaluating slurry fertilizers. Two experiments where soil respiration and soil potential denitrification activity (PDA) was measured at fertilizer addition were performed.

Identifiering av parametrar för tillståndsbedömning av en vattenkraftstation

The report begins with a general inventory of possible technical faults in a hydropower plant and of possible fault indicating measurements. Then an investigation is made concerning a few different faults. Based on this investigation a choice on seal box condition and water leakage is made as problem for a more thorough examination, in which it is concluded that the turbine water leakage is larger when the turbine is put into operation. The examination ultimately results in a computer alarm for faults related to the seal box. Finally a few things are mentioned about flow measurement and pressure measurement in relation to the project as a whole..

Naturlig nedbrytning av klorerade lösningsmedel i grundvatten

Chlorinated solvents are common contaminants in soil and water. Under anaerobic conditions microbes are capable of transforming chlorinated solvents into ethylene which would result in a remediation of the contaminated area. In order to use natural attenuation as a remediation method evidence of continuous degradation is required. Furthermore, the degradation must occur at a sufficient rate and continuous monitoring of the site is needed until the demanded levels are achieved. A field study was performed on the basis of data from a dry-cleaning facility contaminated mainly by perchloroethylene.

Barns tankar om älven : Förskolebarns förståelse av älven och vattnets miljö

AbstractThis research is about pre-school children?s conceptions of the river and the water environment. The aim of this study was to apply a new teaching method based on the outside learning, as well as to test the method and see if it works, i.e. if children get more knowledge this way compared to ordinary methods like teaching in the class-room which involves showing pictures and discussion of them.The main questions in this study were how children get new knowledge through outside learning and how effective this learning method is, i.e. how much they noticed and learned about the river and the water environment as a result of that outside observation.

Askåterföring i Jämtland : biobränslets och askans innehåll av tungmetaller relaterat till markernas geokemi

Using biofuels from regeneration cuttings is becoming more common in Sweden. Ash from the combustion of biofuels contains many valuable nutrients and base cations. The Swedish Forest Agency recommends that ash should be recycled to clearings where biofuels have been removed, to avoid future impoverishment of Swedish woodlands. In Jämtland, in northern Sweden, a large quantity of biofuels are taken out from cuttings but ash recycling has not yet been tried. The aim of this thesis was to examine the conditions for ash recycling in Jämtland regarding to soil chemistry and heavy metal content in soil and biofuels.

Towards sustainable rye cultivation : soil carbon and yield modelling for crop rotations with rye

Using the Introductory Carbon Balance Model, ICBM, five different crop rotations with rye 1. Rye-Ley-Ley-Rye-Beans-Rye 2. Rye-Rye-Rapeseed-Rapeseed 3. Rye-Ley-Ley-Rye-Potatoes-Rye 4. Rye-Rye-Potatoes-Wheat 5. Rye-Rye-Potatoes-Beans-Wheat-Rye-Potatoes-Rapeseed were tested theoretically in four different cultivation scenarios ? Straw left on the field, biogas digestate added as fertilizer. Labelled ?+straw+BD?. ? Straw left on the field, only synthetic fertilizer. Labelled ?+straw-BD?. ? Straw harvested, biogas digestate added as fertilizer.

Ha?llbar sockerro?rsodling fo?r etanolframsta?llning i Brasilien : Hur slagkraftig a?r dagens ha?llbarhetscertifiering och kan den fo?ra?ndra mark- och vattenpa?verkan fra?n odlingarna?

Climate changes today are mainly caused by anthropogenic activities and the increased emissions of greenhouse gases to the atmosphere and this has raised questions on how to reduce the usage of fossil fuels. Ethanol is a good alternative to conventional gas and has been used in Brazil since the 1970 ?s. In Sweden several newspapers has written about the poor working conditions on many farms thus making the Swedish company SEKAB design a certification for their ethanol to ensure that it can be considered to be a sustainable alternative.Furthermore WWF has developed a certification tool called Bonsucro in cooperation with Coca Cola, Ferrero group, BP and Shell. This is due to the fact that no global certification tool has been available up until now.

Bärförmågetillväxt i pålad friktionsjord

Piled friction soil show a set-up which is increasing with the time after installation. The cost could be reduced if the set-up had been taken into account when designing but in Sweden it is very unusual to do that. Previous studies showed that set-up can vary between 25 % and 75 % during the first 90 days after pile installation. This showed that the effect of the phenomenon is difficult to predict. A study involving five projects have been carried out by specifying certain parameters like pile type, method for pile installation and test method for measure the bearing capacity in friction soils located in Sweden.

Värmeåtervinning ur spillvatten : En utredning av möjligheterna med spillvattenvärmeväxlare

The purpose of this report is to investigate the possibilities with drain water heat recovery (DWHR) in residential buildings. Information and relevant theory has been collected and summarized in this report. Calculations have been done for given scenarios to evaluate profits. DWHR heat exchangers use simple technology and have long life-time. The heat exchanger is connected to outgoing drainage pipe and incoming cold-water supply so countercurrent flow is accomplished.

Kanten : mötets poesi

Water connects heaven and earth. Water is the most obvious element of nature. To move in water is for me more than cooling of on a hot summer?s day. It is about freedom and the feeling of being above the state of things.

Konsekvensanalys av dammbrott vid Tjärnviksdalen

This report consists of  an anlysis of the imapct of a dam failure at Tjärnviksdalen in Ragunda, Sweden. The analysis is conducted using the EU model for environmental impact assessments, as well as a group interview. The presentation of the results in the form of a map  where the water level has been raised to the level that the County Board  of Jämtland considers to be possible in case of a dam failure.The result of this work is a detailed analysis of the consequenses that a dam failure would cause, the result consider everything from the direct consequences of the water column to an analysis of the chemical changes that the water would undergo.Parts of the analysis have shown that the purification centre and the old deposits will have the biggest impact on Hammarstrand. Both the purification centre and the deposits will realise chemicals to its nearest environment and because of the flooded purification centre the city will not have the ability to clean the water. .

Förutsättningskontroll och nedbrytningstest på oljeförorenad mark : Preem 2, Karlstad

More frequent and intensified rainfalls are expected to occur due to climate change in the nearfuture. This together with a higher proportion of paved areas increases the pressure on today?sstorm water systems (Risinger, 2014; Boverket, 2013; Stahre, 2006). Traditional storm watersystems (i.e. underground pipe systems) have during last decades started to be questioned(Olshammar & Baresel, 2012).

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