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4695 Uppsatser om Water environment - Sida 51 av 313

Förslag till kväverening i Forsåsystemet genom våtmarksetablering

The last hundred years humans have drastically changed the amount of available nitrogen in nature. Today human activities release twice as much available nitrogen as all natural processes are doing together. We also have degraded nature´s possibilities to take care of nitrogen through the draining of wetlands and straightening of rivers. In order to regain the potential of nitrogen retention in the water systems there now requires a reshape of the landscape we live in. A planned expansion of the mining activities in Garpenberg, Dalarna, would double the content of nitrogen in the waters below the mine.

Språk och minne ? hinder eller verktyg? : En studie om pedagogers förhållningssätt till elever med språkstörning i lärandesituationer, med fokus på arbetsminne

The purpose of this study is to generate knowledge about how teachers relate to students with language impairment in learning situations, with particular focus on working memory. The questions are: What kind of knowledge do teachers have regarding language impairment and working memory?, What experience do teachers have regarding lack of working memory abilities among students with language impairment and which consequences do the teachers believe such defects may have for the students? and How can teachers create a learning environment that reduces the working memory demand for students with language impairment? A review of the field shows that there are gaps to fill regarding students with language impairment and working memory. Language impairment has so far been neglected by researchers and within the public debate. How working memory capacity affects the students has only recently begun to receive attention in school and research.

Den tillgängliga stationen : Gestaltning av en stationsmiljö på basis av tillgänglighet

This report is about accessibility in a station environment. Studies have been made about how an accessible building should be designed. Accessibility is an important issue when striving for a society with equality as the foundation. Sweden is one of the most accessible countries when speaking about the built environment. A result of prosperity and a well-managed democracy.

Byggnadsfysikaliska riskbedömningar : Metod för tidig hantering av fuktsäkerhetsfrågor

The purpose of this degree-project was to investigate the possibilities for primary air preheating into the two smallest waste incineration boilers of Halmstad Energy and Environment. The investigation is a pre-study which has the primary goal to evaluate technical and financial offers from companies that manufacture primary air preheater, and investigate if it is technically and financially profitable to do a purchase on primary air preheaters in the future.In the pre-study it is proposed that it is most efficient to have individual primary air preheater, one for each incineration boiler and the primary air are also proposed to be preheated by hot water in the pre-study. Further in the pre-study it is proposed that the heat-exchanger should have plain tubes instead of finned tubes, to avoid getting dirty fast. The space in the boiler-room is limited, and therefore the major problem was to fit in the primary air preheaters into the boiler-room. By comparing the different offers from the companies, the result in the pre-study shows that the offer from the company C.A.

Spelutveckling och lansering av applikation till Android

For several years Uppsala University together with several companies has been involved in a WISENET project aimed at improving railway transport security. By placing a sensor system near the wheels of each wagon, the temperature of the bearings can be measured and transmitted to a collector placed centrally on the wagon. This in turn transmits the collected data to RFID receivers placed intermittently along the railway.As the signals are transmitted wirelessly, problems may occur as the antennas get dirty or coated with ice and snow. To determine the effects of these coatings, several tests were performed examining the reflection coefficient S11, the impedance Z11 and the efficiency eta of an antenna, and how they varied when various coatings were placed over the antenna. Examined coatings were ice, snow and water to determine the effects of weather, and various metal-based coatings: powdered iron both pure and partially oxidized, and iron ore granules.

En studie av Växjö stadspark : med fokus på rekreation och sociala värden

Many people choose to live in urban environments. Since everyday life in many cities is characterized by a high pace it is important that good recreational areas, with the possibility of recovery, are available to the population.This paper is based on a case study of Växjö city park, which is the area surrounding the lake Växjösjön. The park and the lake are of great importance to the citizens. The lake Växjösjön has for a long time been affected by eutrophication, which has caused major problems as algal blooms and fish mortality. An extensive lake restoration was carried out in the 1990s in order to save the lake.

ALK?RR - K?LLA ELLER S?NKA F?R V?XTHUSGASERNA METAN OCH LUSTGAS? Empirisk studie av v?xthusgasutbyte i kustn?ra alk?rr p? den svenska V?stkusten.

Due to global climate change and the rising levels of greenhouse gases (GHG) in the atmosphere, the interest for seeking solutions for mitigation has increased. While much attention has been directed towards technical solutions such as carbon capture and storage (CCS), biogenic carbon sinks has also garnered significant attention. Previous studies have shown that coastal ecosystems such as seagrass meadows and mangroves have a much greater capacity for storing carbon (C) compared to terrestrial ecosystems. That raises the question if other coastal ecosystems, such as coastal wetland forests, that previously haven?t been considered as blue carbon habitats also contribute to coastal carbon sink capacity.

Threats and opportunities for the survival of the Yangtze finless porpoise

The Yangtze finless porpoise (Neophocaena phocaenoides asiaorientalis), is a small freshwater cetacean which has recently fallen dramatically in number. It is an endemic species for the Yangtze River and unless drastic action is taken, it risks the same fate as the now functionally extinct Yangtze river dolphin (Lipotes vexillifer). Threats to the porpoise are diverse but they have in common that they are caused by man. Development of the river has been made to supply a growing human population with food, hydropower, and to reduce the risk of flooding. These changes have resulted in a degraded habitat for the porpoise.

Rationell produktion av platsgjutna stommar för flerbostadshus

The purpose of this degree-project was to investigate the possibilities for primary air preheating into the two smallest waste incineration boilers of Halmstad Energy and Environment. The investigation is a pre-study which has the primary goal to evaluate technical and financial offers from companies that manufacture primary air preheater, and investigate if it is technically and financially profitable to do a purchase on primary air preheaters in the future.In the pre-study it is proposed that it is most efficient to have individual primary air preheater, one for each incineration boiler and the primary air are also proposed to be preheated by hot water in the pre-study. Further in the pre-study it is proposed that the heat-exchanger should have plain tubes instead of finned tubes, to avoid getting dirty fast. The space in the boiler-room is limited, and therefore the major problem was to fit in the primary air preheaters into the boiler-room. By comparing the different offers from the companies, the result in the pre-study shows that the offer from the company C.A.

Ett flervariabelt feldetekteringssystem för övervakning av bärlagertemperaturen i vattenkraftturbiner

The purpose of this thesis work was to develop an automatic fault detection system for surveillance of bearing temperature in hydropower turbines. The parameters used except the bearing temperature were cooling water temperature and cooling water flow. A simple static model based on data sampled every minute was developed to estimate the bearing temperature. Then a detector for detection of change in bearing temperature based on the CUSUM-algorithm was designed. Since the amount of data was very small the developed model was too uncertain to be used in a working system.The designed fault detection system showed to work well for the available data.

Traditionell ekologisk kunskap i en framtid med lokala, självförsörjande och urbana samhällen

Several scenarios point toward a future where we are far more people on Earth than today, where most of those people will live in cities and where oil no longer dominates in the transport systems and in agriculture as an energy source and where less energy will be available to us. The report investigates what areas in traditional ecological knowledge that can contribute to the transition that follows a future with less energy and establishes three areas with the potential of becoming important: areaspecific biological knowledge in societies that are more dependent upon its surrounding environment and its natural prerequisitesthe local management of these biological resources, which often means a fair sharing and sustainable handling of the resources and which has been observed in Nobel price awarded Elinor Ostrom?s researchthe world views that lie behind how the environment is considered and managed, world views that can inspire and point toward how we in the future should formulate world views that do not give the destructive modern management of the environment It is also noted that the magnitude of the city living in the future is a historical news and that very little research has been done in how traditional knowledge can be transferred into this kind of living..

Exosomes as a potential mechanism of intercellular spread of prion protein

Structural rationalizations and regionalization of the agricultural sector in Sweden has lead to unevenness in thedistribution of plant nutrients. Nutrients are lost from crop producing farms as harvest products are sold, whilefarms with animal production often have manure in excess of their needs. In addition to this the retention ofwater and nutrients in naturally occurring wetlands has decreased due to a reduction of wetlands in number andsize in the agricultural landscape. This increases nutrient levels in agricultural run-off and causes eutrophicationas well as nutrient losses from arable soils. One potential solution to both problems would be to store nutrientrichsurface water from agricultural areas and use it for irrigation of agricultural crops.

Metodik för bestämning av åkerdikens status : fallstudie av ett dike i Munktorps socken

Agricultural drainage ditches are links between fields, lakes and oceans, having the potential to transport e.g. sediment and nutrients. When in a good condition, drainage ditches can act as sinks for e.g. phosphorus and sediments and prevent eutrophication downstream. The aim of this study was to determine the condition of one agricultural drainage ditch and to come up with suggestions for appropriate measures. The aim was also to determine which of the ditch?s properties that were possible to evaluate visually, which processes they represented as well as which properties required complementary physical analysis. This in order to contribute to the work of developing a method for determining the status/condition of agricultural drainage ditches.


Rökgaskondensering och skrubber till vedeldade villapannor :

This paper deals with the opportunities for the technique of condensation, for wood fired household heaters, on the Swedish market. In this project the condenser is preceded by a scrubber and both energy exchange and separation of unburnt particles have been studied. The facility studied is connected to a wood stove at 30 kW. The tests would show that the effect from the stove never reached above 16 kW. This might be a result of the low temperature of the water going into the stove, from the condenser. In addition to this the wood was not of highest quality and the stove could have needed some maintenance before the tests.

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