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1508 Uppsatser om Storm water modelling - Sida 5 av 101

Modellering av avrinning från gröna tak : Avrinningskoefficienter och modellparametrar

Expansion och förtätning av städer leder till att såväl areal som andel hårdgjord yta ökar i våra stadsmiljöer. Detta genererar en ökad dagvattenavrinning eftersom regnvattnet inte har samma möjlighet att infiltrera i naturmarker och grönområden. Den ökade mängden dagvatten riskerar att orsaka problem i områden där ledningsnätet dimensionerats för de dagvattenmängder som tidigare varit aktuella. Att utöka ledningsnätets kapacitet är ofta mycket kostsamt och det är därför önskvärt att istället minska belastningen på de befintliga systemen. En allt vanligare metod för detta är att byggnaders takyta bekläds med växter, så kallade gröna tak.

Tjänligt vatten i kranen - Membranteknik gör det möjligt : En utredning av pilotförsök i Glemmingebro

Nanofiltration is a proper way of preparation of drinking water. The process has a lot in common with reverse osmosis where a semipermeable membrane is used to separate a pure water flow from the remaining water. A pilot plant was used to ensure that nanofiltration is a suitable technology for a specific waterworks station in Glemmingebro, Ystad. The purpose was also to find out if a pH-adjustment is needed for feed water in a possible full scale plant.  In this case nanofiltration is used mainly to remove sulphate and calcium since the raw water contains concentrations of these substances which exceed the limits for potable water. It is important to receive a high recovery (RC), otherwise the deliviery of water won?t be high enough.

Kreditgivares agerande vid sjunkande skogsfastighetspanter

Background: The hurricane in the south of Sweden in January 2005 was the worst storm in Sweden for the last hundred years. The storm named Gudrun has blown down forest that according to estimation is corresponding to one year of cutting down in the entire country.Purpose: The purpose of this thesis is to describe how credit granters act when facing falling forest real estate mortgage and describe if they will make considerations due to the storm in the south of Sweden 2005.Method: With help of a qualitative method, we investigated how the credit granters act when facing falling forest real estate mortgage. Interviews were obtained with three credit granters, SEB, Landshypotek and FöreningsSparbanken in the county of Jönköping and Kronoberg.Conclusion: The conclusion is based upon the empirical study, the analysis and our own reflections and it shows that the credit granters do not change their policy concerning credit granting to forest real estate properties. The policy of the credit granters has proven to be valid even in this extreme situation..

Vem för de törstigas talan? : En studie av debatten kring vattensektorn

1.1 billion people are today living without sustainable access to improved water. The debate over the water sector has been dominated by the discussion over whether public or private actors are the most competent to manage it. In this paper the arguments pro and contra the two positions are presented to try to overview the debate and to try to find new ways to approach the question of the people living without clean water. By examining possible alternatives towards the discussion of public and private actors, it might result in some new approaches on how to move closer towards a solution. One alternative is local, small- scale projects which focus on the situation of the targetgroup in most need.

Riskbaserat provtagningsprogram för mikroorganismer i Gäddviks vattentäkt

Risk-based sampling program of microorganisms in the water source in northern SwedenAfter several disease outbreaks caused by parasites in the drinking water during the last years, it is more essential than ever to insure that the water supply companies have enough barriers to counteract the presence of microorganisms in the outgoing water. It is also discussed whether climate changes such as increased precipitation can have a connection to the increased cases of parasites in water sources. The water source at Gäddvik is Luleå municipality?s largest and provides drinking water to 64 500 of Luleå?s 74 000 inhabitants. The investigation of microorganisms in the water source, especially in the Lule River has not been as prioritized as the sampling of chemical parameters.

Hur mycket "mjölk" ska det vara i mjölken, och hur styr vi det?

In most countries, the dairy industry focuses on the volume of milk produced instead of its composition. This results in a high content of water and a lower proportion of fat and protein. A high proportion of water is not desirable when processing the milk into various dairy products like cheese, cream and milk powder. High water content also increases the costs for transport and storage, and also an unnecessary, albeit marginal, strains on the world?s water reservoir.

Uppföljning av dagvattenmagasin på Lärkgatan i Växjö stad. : Monitoring of storm water management on Lärkgatan in Växjö city.

Dagvattenmagasin byggs för att fördröja och avlasta ledningssystemet dådagvattenmängderna i dem är stora för att sedan leda tillbaka vattnet i ledningssystemetnär vattenmängderna har sjunkit.Examensarbetet syftar till att undersöka och analysera vad som behövs göras för attanvända ett dagvattenmagsinet som är dimensionerat för tioårsregn redan vid femårs- ochtvåårsregn.Arbetet grundas på fältstudier och analys av hur systemet är uppbyggt. Beräkningar hargjorts för studera flöden i ledningar och fyllnadsgrad i magasin. Resultatet visar att det ärmöjligt att med relativt enkla åtgärder kunna utnyttja det aktuella magasinet redan vid 2-och 5-årsregn..

Habitatpreferenser hos tjockskalig målarmussla (Unio crassus) med avseende på vattendjup och beskuggning.

The thick-shelled river mussel (Unio crassus) is a red listed species classified as Endangered (EN) and is also considered within the Habitats Directive. The distribution in Sweden is fragmented and it is mostly occurring in the south eastern parts. We investigated the presence of Unio crassus in a section of the stream Storån, Östergötland County, from Falerum to the inflow into Lake Åkervristen. The environmental parameters investigated were water depth, bottom substrate, shading, water velocity and the slope over the water surface. In this thesis I have focused mainly on water depth and shading, comparing sites with and without mussels.

Utveckling av en ytmonterad fördelningsmätare som underlag för individuell debitering av vattenförbrukning i fastigheter

The master thesis, conducted at Metrima AB, concerns the development of a non-intrusivedistribution meter as a basis for individual tap water billing in apartments.The project is conducted in response to the market interest in individual tap water billing inapartments as an answer to environmental concerns regarding water consumption. Due to thehigh installation cost of traditional water meters, a new method of determining waterconsumption, without having to cut water pipes, is proposed.The proposed method distributes the total water consumption for an apartment complex toindividual apartments according to distribution meters, measuring water run-time, in eachapartment. The water run-time is estimated by measuring the water pipe?s outward vibrationsand temperature changes.A test environment was established and a prototype built, using a tilt- and vibration sensor forvibration sensing and a precision temperature sensor to measure temperature changes. As bothsensors work well in the test environment, further testing was done in 3 apartments for aduration of 5 days.

Rationell riskanalys inom VA-verksamhet med avseende på säkerhet, hälsa, miljö och kvalitet

This master thesis is developed based on the desire of the water and sewage department in the municipality of Karlskrona. The department, which vouches for the quality of produced drinking water and sewage cleaning, was in need of help dealing with risk analysis.The water and sewage department is obliged to identify and assess risks according to Swedish legislation. However, no guides for this purpose regarding safety, health, environment and quality were available. The aim of this report was to accomplish a guideline for the performance of risk analysis within water and sewage plants. If the guideline is used, the requirements in the legislation will be obtained.

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.

Effect of vortex-processed water on tomato (Solanum lycopersicum) plants

This pilot study examined whether treatment with Vortex Process Technology (VPT) of the irrigation water used on tomato (Solanum lycopersicum) plants had any effect on plant growth. In a block experiment, with two blocks comprising 12 vases containing 1 L water and two tomato plantlets, treatment in which, nutrient solution was based on Vortex-treated water was compared with an control using untreated water. All vases were kept in a static aerated culture system in a daylight chamber for four weeks. The results showed that the effect of the two blocks exceeded the effect of vortex treatment in terms of leaf area and weight of fresh and dry matter. Plant height, stem width and internodal length were significantly different in tomato plants grown in Vortex-processed water compared with the untreated control.

Vattenanläggningar som gestaltningselement i offentliga miljöer :

Water constructions - as a design element in public spaces is the title of this Master thesis, with a focus on waters function and meaning in the urban environment. By way of introduction, mans relationship to places is described and the factors that contribute to the reality that we prefer some places more than others. A good place to stay is open but well defined, gives protection, offers a good view and is varying in topography and vegetation, together with contents of single landscape elements like visible water. This study then continues to discuss mans relationship to water and its means for our wellbeing. Despite the fact that people have a different relations to water due to personality, background and age, it?s an element that raises positive feelings, interest and aesthetic pleasure for most people.

Förstudie till våtmark i Rimbo : Design för optimal hydrologi och kväverening

The euthropthication of the Baltic Sea is a threat that is beginning to be taken seriously by the governments concerned. In Sweden, regulations concerning the allowed nitrogen (N) concentration in the effluent water from wastewater treatment plants are being tightened up. The Rimbo wastewater treatment plant has been imposed to reduce the annual mean concentration of total N in the effluent water to levels below 15 mg l-1. A more and more common way to reduce the nitrogen level in wastewater is to let the water pass through a wetland. This study investigates the possibility to build this kind of wetland at the outlet of the Rimbo wastewater treatment plant.A prestudy of the topography, soil characteristics and groundwater flow indicates that the land area in question is well suited for the construction of a wetland.

Hot och risker med dricksvattenförsörjning : Förutsättningari tid och rum för bevarande av Sundsvalls och Timrås dricksvattenförsörjning

This study describes what impact activity within Wifstas, Matfors,Grönstas and Nolbys water protection areas have on the quality of the drinkingwater. It considers the use of the area, environmentally dangerous activitiesin the past and present, the geology?s part, what harm hydroelectric power damsmay cause if they break and how climate change might affect the area in thefuture. It also takes into consideration activities outside the waterprotection areas which might have a suspected impact on the water quality. Theresults of the study are that pollution from infrastructure such as roads, orwastewater from treatment plants may cause occasional contamination of thedrinking water, foremost due to flooding.

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