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233 Uppsatser om Groundwater modelling - Sida 2 av 16
Hållbar vattenförsörjning i områden med vattenbrist : Sustainable water supply solutions for areas affected by water shortage
In some coastal areas in Sweden water shortage sometimes appears because the withdrawal of groundwater is greater than the groundwater recharge. It creates a situation where the available groundwater is insufficient to support residents and businesses with drinking water. The high withdrawal of groundwater also creates a risk for saltwater intrusion to drinking water wells. The problem most commonly occurs during the summer when the groundwater recharge is low, but the population is high, due to tourism and summer residents.The purpose of this study was to investigate how local water supply in areas affected by water shortage can be solved as sustainable as possible. The work was divided into three parts where the first part comprised of a literature review on water systems in which four different options were investigated: artificial groundwater recharge, rainwater harvesting, desalination and water reuse.
Spridning av bekämpningsmedel i banvall : Modellutveckling och känslighetsanalys
The stability of railway embankment is essential for safe transport. In order to ensure safe transport, water should be allowed to freely drain. Furthermore, as the engine driver has to be able to see signs, and people working on the embankment are supposed to easily see flaws on the rails to ensure safety for the passing trains, plants should not be allowed to grow on the embankment. In Sweden there are 12 000 kilometers of railway tracks and 25?30 % of them are treated for weed control every year.
Kvävestatus och risk för nitrifikation i två avverkade skogsområden i Halland
Nitrogen deposition leads to environmental damage in areas where the nitrogen deposition is high. Southwest Sweden receives an annual nitrogen deposition of up to 20 kg N/ha. Nitrogen that is not assimilated by the vegetation is accumulated in the soil, which may lead to nitrogen saturation and an elevated risk of nitrogen leaching. Nitrogen leaching from forest areas in southern Sweden has proven to be higher than from agricultural areas, which have been thought to be the main contributors to elevated nitrogen levels in rivers and lakes. The amount of nitrogen that leaches depends on the fraction of the total nitrogen in the soil that consists of nitrate, since nitrate is easily transported through the soil.
Grundvattensänkning till följd av järnvägstunnel genom Hallandsås : miljökonsekvenser relaterade till förändrad kväveomsättning i mark
This thesis was carried out to give some background information to a report of SLU (Swedish University of Agricultural Sciences) for the Swedish National Rail Administration (Banverket). The requested information was to provide basic data for an environmental impact assessment of the construction of the tunnel through Hallandsås. The aim with the thesis work was to discuss and quantify the leaching of nitrate and the emission of nitrous oxide from the soil at the groundwater level established through the tunnel project. The nitrogen related processes that could be affected were described and discussed. The different areas where a decreased groundwater level can cause changes in the nitrogen processes are the wet and moist areas.
Påverkan på Valboåsen från verksamheter inom Svedens industriområde samt närliggande områden : hot mot grundvattnets kvalitet och kvantitet?
The aim of this work was to find out what potential contaminants from roads, residential area and businesses within Svedens industrial area that can affect groundwater quality and quantity. Data collection was from SGU, VISS, internal material from Gävleborg county Administrative Board and Gävle municipality archive. GIS software ArcGIS was used to create the map images in the work.
The studied area is located approximately ten kilometers west of Gävle city and consists of the esker Valboåsen, which is a glacifluvial deposit that in its central parts consist of coarse material that is overlaid by sand, clay and silt. North of esker Valboåsen there are the river Gavleån which has an inflow to the groundwater in the esker. This inflow represents the largest part of the groundwater recharge.
Inventering av förorenade områden enligt MIFO-fas 1 : Erasteel Kloster AB, Söderfors
Erasteel Kloster AB Söderfors have been commissioned by the county administrative board in
Uppsala län to make an inventory of possible contaminations in theirs industrial- and landfill areas on the basis of the Swedish Environmental Protection Agency?s; ?Method of Surveying Contaminated Sites-phase 1? (MIFO-fas 1). The inventory starts with maps and archive studies, place visits and interviews, and finally a risk classification is done. A risk classification is a compilation of four categories; pollutant toxicity, contamination level, possible spreading condition of the pollutant, sensitivity and protection value of the environment.
In this paper five partial areas (Holmen- and Jörsöområdet, Järnsvampsområdet,
Ingsådeponin, Östra verken and Myrområdet) have been described from a historical point of
view. Only parts of four areas have been risk classified (Holmen- and Jörsöområdet,
Järnsvampsområdet, Ingsådeponin and Östra verken), due to that the other areas isn?t own by Erasteel Kloster AB.
Holmen- and Jörsöområdet
Holmen- and Jörsöområdet have during the entire activity time been carried out as the
production core in the company.
Inventering av bergborrade brunnar för dricksvatten i område med risk för salt grundvatten : en utredning av grundvattensituationen i Vreta-Ytternäs i Uppsala kommun
The city of Uppsala and its surroundings are a very expansive area. A prerequisite for a sustainable development of the area is well-functioning supply of drinking water. In Uppsala municipality, the Uppsala esker and Vattholma esker are the groundwater storages for drinking water. Besides the eskers, other sources of qualitative groundwater in the Uppsala municipality are relatively poor and more than half of the area consists of ground conditions with a risk of saline groundwater. The neighbourhood of Vreta-Ytternäs is situated 10 km south of Uppsala, in the area with risk of saline groundwater but outside the municipal water supply.
Nitrat i grundvattnet : Modellanalys av vattenflöde till Hörviks vattentäkt
A well, situated on Listerlandet in the western part of Blekinge in Sweden, has a very high content of nitrate. Water with a too high content of nitrate is hazardous to human health, in particular to small children. The area surrounding the well is mostly drained agricultural land with some larger farms for chicken and mink. The well takes its water from the bedrock and is deeper than most other wells affected by nitrate. The bedrock in the area is dominated by limestone with a relatively high flow of water.This thesis was performed in order to find the source of the nitrate.
Design av Riskdatabas : En studie för effektivare hantering av risker
Risk management is a key competency that is constantly being researched how it can be improved within project management. The risk management process consists of four major steps: identify risks, assess the risks? significance on the project, evaluate and address the key risks and follow up.The majority of companies seem to neglect certain identified risks, and decide not to mitigate if the risk does not cause adverse effects to the business. To counteract undesirable consequences and help organisations to become more effective at managing risks an initial work has been conducted for a risk repository.The project develops a proposal on the design of a risk repository which aim to effectively support a database implementation. The study includes literature studies which resulted in a relational model for database implementation.
Transporttider för vatten i närområdet till en vattentäkt : spårämnesförsök i en isälvsavlagring
When establishing a groundwater protection area it is of great interest to be able to estimate the transit time of the groundwater from different places of the aquifer to the withdrawal well. These estimates can be uncertain due to heterogeneities in the aquifer. As a part of the work to develop methods for a more certain delineation of protection areas, a tracer test was performed in an esker located 25 kilometres NW of the town Uppsala.The purpose of this master thesis was to perform, describe and evaluate the tracer test. Travel times from the tracer test should then enable comparison against stochastic simulated travel times of the groundwater in the area.Three dyes (rhodamine WT, uranine and naphtionate) and a salt (NaBr) were used in the tracer test. The tracers were injected in four different wells located 25 meters from a pumping well.
Skattning av den integrerade hydrauliska konduktivitetens variation kring Tunåsens infiltrationsanläggning : En utredning av påverkan från möjliga osäkerheter i befintlig information
Estimation of the variation in the integrated hydraulic conductivity around the Tunåsen infiltration facility - An investigation of the effects of uncertainties in existing informationAlmost half of Sweden?s drinking water volume is produced from groundwater. The main fraction of this is extracted from eskers, some of which allow for very large extraction rates. Despite this, the groundwater volume is not sufficient in some areas. This has led to an extensive use of artificial recharge.In Uppsala, the total volume added through artificial recharge is divided between four infiltration facilities.
Mean value modelling of a poppet valve EGR-system
Because of new emission and on board diagnostics legislations, heavy truck manufacturers are facing new challenges when it comes to improving the engines and the control software. Accurate and real time executable engine models are essential in this work. One successful way of lowering the NOx emissions is to use Exhaust Gas Recirculation (EGR). The objective of this thesis is to create a mean value model for Scania's next generation EGR system consisting of a poppet valve and a two stage cooler. The model will be used to extend an existing mean value engine model.
Modellbygge av mekaniksystem och riktmotorer i stridsvagn 122
This master thesis is one part of a project, called ?StabSim?, with the purpose to develop a simulation model for the align and stabilisation system in main battle tank 122. The origin of this project is that it should be possible to make control analysis without risking any hardware. Besides that it will be easy to change components in order to investigate the behaviour of the system. The report includes modelling of tower and weapon mechanics and also the modelling of the synchronous motors, which control these.
Utvärdering av den upplevda användbarheten hos CySeMoL och EAAT med hjälp av ramverk för ändamålet och ISO/IEC 25010:2011
This report describes a study aimed at uncovering flaws and finding potential improvements from when the modelling tool EAAT is used in conjunction with the modelling language CySeMoL. The study was performed by developing a framework and applying it on CySeMoL and EAAT in real life context networks.The framework was developed in order to increase the number of flaws uncovered as well as gather potential improvements to both EAAT and CySeMoL. The basis of the framework is a modified version of the Quality in use model from ISO/IEC 25010:2011 standard. Upon the characteristics and sub characteristics of this modified model different values for measuring usability where attached. The purpose of these values is to measure usability from the perspectives of both creating and interpreting models.
Patogenes för prostatacarcinom hos hund : en jämförelse med människan
This thesis investigates the possibilities offered to a working landscape architect by anincreased and altered use of digital 3D environments. A basic assumption is that increased useof digital three-dimensional environments promotes the creative processes and presentationoptions of landscape architects.The thesis is based on literature studies and communication with working landscapearchitects, and includes an investigation of the visualization methods available in the Blender3D modelling software. The thesis provides a thorough survey of what it means to model inthree dimensions, as well as of what modelling methods are feasible for a landscape architectto use. As landscape architects, we work with human and unique processes, and thus it isdifficult to develop standardized and automatic software for our profession. One possiblesolution is to turn to open source development, where software and models are shared andanyone can contribute.