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1758 Uppsatser om Water regulation - Sida 17 av 118

Vattennivåreglering i Avesta Lillfors : På uppdrag av Fortum Generation AB

I denna rapport utreds olika metoder för att kunna reglera vattennivån i vattenkraftverket Avesta Lillfors i Dalarna. Två kraftverk ligger endast 900 m uppströms och detta gör att svarstiderna blir korta och regleringen blir lätt nervös. Att använda sig av vattennivåreglering i ett kraftverk för-enklar dess styrning då anpassning till inflödet sker automatiskt.En flödestabell har tagits fram genom mätningar i turbinen, med hjälp av Winter-Kennedy-metoden. Denna tabell används för att kunna fram-koppla regulatorn och därmed dämpa stora variationer i inflödet. Dessu-tom har en modell av älven skapats och testats med en återkopplad PID-regulator.

Aggregatstabilitet, jordbearbetning och fosforförluster i ett typområde på jordbruksmark :

Large amounts of phosphorus (P) are lost from the arable land due to water erosion. Both phosphorus attached to particles and dissolved phosphorus (mainly phosphate) are transported away with drainage-water and surface runoff. Good soil structure is important in minimizing these losses. In this study, soils from 50 fields were analysed with respect to aggregate stability as measured by dispersion of clay together with the content of total phosphorus (TotP), particulate phosphorus (PP) and phosphate phosphorus (PO4P) in the water phase. All soils were clay soils with clay content varying between 21 and 54%.

Undersökning av miljöstatusen i Gothemsån / Dalhem i anslutning till utsläpp av lakvatten från sopdeponi i Roma 2010

In October 2010 it was discovered that leach water had been released from a waste deposit directly into a ditch during a period from March until October 2010. The river Dalhemsån runs close to the waste deposit, just about 10 meters from the ditch. By studying the benthic fauna it was discovered that the environmental status of Dalhemsån is bad in this part of the river, but the discharges of leachate from the waste deposit does not seem to have deteriorated the water further since May 2010..

Kvantifiering av föroreningstillskott från dagvatten inom skyddsområdet för Göta Älv : en simuleringsstudie med modellen SEWSYS

The river Göta Älv reaches between Vänern and Gothenburg and is the main raw water source for Gothenburg that supplies about 700 000 people with water. To protect and maintain a high water quality, continuously samples and water analyses are made throughout the river. In 1998 a protection area was founded between surte and Lärjeholm where the raw water intake is. This was made to increase the awareness of the importance to protect the water. However, there is a lot of contribution of untreated stormwater to Göta Älv within the protection area.Göteborg Water and Sewage Works commissioned this thesis where two areas, Tagene industrial area and Kärra residential area, with untreated stormwater outlets within the protection area are studied.

Bäddodling av matpotatis :

This study investigated potato growing in beds as an alternative to conventional ridges.It was based on results from field trials on bed-grown potatoes carried out by Halland Rural Economy and Agricultural Society in 2007, studies of literature and interviews with farmers with experience of bed growing of potatoes. Due to their shallow root system, potatoes are one of the most drought-sensitive crops. Potatoes are often grown on sandy soils with poor water-holding capacity. Factors such as total yield, tuber size distribution and quality defects are negatively affected when water becomes insufficient. Wide beds have a more flat top which leads to more uniform water infiltration. Further on, beds have lower soil surface area due to its shape, and therefore, retain water more efficient. In the field trials, which were carried out at the Stjärnarp Estate near Halmstad, potatoes were grown in beds alongside a conventional ridge-grown crop.

Analys av vattenkvalitet i ett kommunalt badhus

Bath has been a part of human history for a long time. Today bathing/swimming inmunicipal pools is for people of all ages and it is possible to take swimming courses,exercise or enjoy recreation. The municipal indoor pool of Hogdalen in Sweden wasbuild in the sixties and has had problems with high levels of heterotrophic bacteria. Thefacility has two larger pools, one adventure park for young kids, two smaller bath tubsand a jacuzzi. To improve water quality UV light and coal filter were installed inOctober 2009 to the already existing purification system.

Motivation : En studie om lärares och elevers syn på motivation i skolan

I vårt examensarbete undersöker vi olika typer av motivation. Vårt syfte med arbetet var att undersöka lärares syn motivation samt elevers egen motivation i skolan. De frågeställningar vi utgick från var: 1. Vilken typ av motivation har elever i år 4 och år 5? 2.

Fosforavskiljning i reaktiva filter vid småskalig avloppsrening

An excessive input of nutrients to lakes and other water bodies has created a problem with eutrophication in Sweden. Untreated, or partially treated, domestic sewage is a major source for discharge of phosphorus (P), which is the nutrient most frequently responsible for eutrophication of most fresh waters and the Baltic Sea. The waste water can be cleaned by filter materials, which have a high P-retention ability and which after saturation may be used as fertilizers. Four potentially suitable filter materials were tested in batch- and column experiments in this study. In the batch experiments, the following materials were shaken with waste water in time series ranging from 5 seconds to 60 minutes: coarse (1-4 mm) and fine (0-2 mm) Polonite® (heated bedrock from Poland); Filtralite® (light expanded clay aggregates with limestone added before burning); water cooled blast furnace slag (BF-slag) and BF-slag mixed with 10% burned limestone.

Analys av dricksvattenrening med metoderna Mikrobiologisk riskanalys (MRA) och God desinfeksjonspraksis (GDP)

Drinking water is produced from raw water and is either from groundwater or surface water. This thesis aims to find out if the cleaning process of raw water is sufficiently effective. This is important because consumers are otherwise at risk of waterborne infection caused by pathogens. There are three groups of pathogens; bacteria, virus and parasite. These have different characteristics which mean that they require different water treatment to be separated.

Radonfritt boende : Stegen till att eliminera radongas med rätt Grundläggningsmetod

People who live in northern part of the world spend much more time indoors than those who live in warmer countries. In addition that home should be safe, it should also protect one against heat, cold, sunlight and pollution. The indoor environment is affected by installations, material and how the building is formed. Those anomalies that are visible, felt or smelled can be noticed and be rectified. But it?s much more difficult if these abilities are missing.

Identifiering av fosfatfosfors käll- och flödesfördelning i ett litet jordbruksområde

Eutrophication of lakes and streams are nowadays a well known environmental problem and implies an enrichment of the nutrients phosphorus (P) and nitrogen (N). Phosphorus is considered to be the most important component for the growth of aquatic plants and leads in too large quantities to an intensification of growth. Phosphate (PO4) is the fraction of phosphorus that can easiest be taken up by plants and thus have the greatest impact on eutrophication. Increased plant growth in lakes and unfavorable conditions for aquatic animals are two examples of negative consequences. A significant portion of the increased nutrient supply to nearby water can be derived to phosphate leaching from agricultural areas, where private sewers and agriculture is two main sources.

Sjuksköterskors erfarenhet av att vårda patienter med självskadebeteende

The Swedish industrial society has left several areas with contaminated soil and water which today is of danger for the environment and human health. One of these areas with contaminated soil and water is the region where the former Glava glassworks operated during 1859 to 1939. The main object in this study has been to study the responsibility for the contaminations according to the Environmental Code. The method used is a qualitative content analysis of relevant literature to answer the following questions:What types of contaminations can be found in the area of Glava glasswork and what health issues can these cause?What kind of activity has been conducted in the area that have caused the contaminations in soil and water?According to law, what are the responsibilities for the contaminations in soil and water at Glava glassworks?The contamination in the region has been confirmed to originate from the glasswork due to the environmental engineering survey made in the area in 2009.

Barn med autism : En studie i hur skolarbetet kring barn med autism ser ut

This essay is about how working with children with autism works with the laws and regulations that fall under the Compulsory School Ordinance and Lgr11 (Compulsory for primary school, preschool classes and kindergarten). The aim of this work was to examine various educators thoughts, experiences and practices related to children with autism in primary school. The study is based on three questions: what kind of rights regarding support do children with autism have in the Swedish primary school, according to the primary regulation and Lgr11? How do the selected primary schools work with the support of children with the diagnosis of autism? And how well does the affected educator?s think that the support works?To answer these questions, four qualitative interviews with various educators, were made. My results show that all four educators believe that inclusive labor of children with autism is a good thing for everyone, as long as it is done properly and with the right order, so that the child with autism gets the opportunity to be part of a social group.

Vinterförvaring av Pelargonium x hortorum :

There are many different recommendations on how to keep pelargoniums over winter, but most of the recommendations suggest ?the higher the temperature, the more light and water the pelargonium needs?. The purpose with this paper is to try to explain the best and the worst results that are achieved with different storage alternatives of zonal pelargoniums. The results are based on an orientating investigation carried out in January-February, and a questionnaire that members of the Swedish Pelargonium Society answered to. Both the orientating investigation and the questionnaire showed that zonal pelargoniums are best stored light and cold but frost free. They should be irrigated according to their needs which is when the soil is dry, about every second to third week. Zonal pelargoniums are very resistant to drought and can survive without water for at least 44 days, both when kept under light and cold as well as under light and warm.

Förändringar av marknadsdesign och deras påverkan på balanshållningen i det svenska kraftsystemet : En kartläggning och analys av de balansansvarigas arbetsgång

A future expansion of wind power in the Nordic power system makes the balancing for the transmission system operator Svenska Kraftnät (SvK) more complicated. Up to the hour of delivery the balance responsible parties? (BRP) makes prognoses and plans, for consumption and production, to help maintain the balance in the electrical grid. How well this is accomplished is affected by the setup of the market design. Therefore SvK has proposed the following possible changes in market design: Increase the imbalance costsIntensify the regulation of imbalancesIncrease the temporal resolution on the different marketsPresent the prices for balancing power in real-timeModify the balancing market to simplify auction of consumption bidsA mapping over the BRPs? processes within planning and trading on the day-ahead, intra-day, and the balancing market has been performed in this thesis.

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