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4335 Uppsatser om Water quality - Sida 64 av 289
Undersökning av vissa beläggningars påverkan på antenners effektivitet i tågmiljö
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.
Resonans
This report describes how the system may be exposed to oscillations and how this can lead to resonance. Resonance is a phenomenon that occurs when a system is affected by external periodic oscillations with frequencies close to the system's natural frequencies. Structures subjected to resonance can risk great damage and destruction, why resonance is something that is important to take into account when designing structures. Alternative ways to counteract resonance is to supply damping in the system. Damping means that the resonance decreases instead of letting the amplitude increase.The report discusses some examples on constructions that have experienced the effect of resonance.
VISION SJÖSTAD : Flytande Bostäder
Floating housing is a concept gaining ground in Sweden. The dwellings are different in many ways from traditional homes, not only regarding flotation, but also several other technologies. The purpose of this thesis is to emphasize the qualities that exist in living on water. The ambition was to present a proposal for a floating residential area located in Jönköping, containing homes of varying sizes, and to present their technologies. In order to find inspiration and solutions studies have been made on existing floating homes in Stockholm and Kalmar, focusing on their technical and functional solutions.
Karakterisering och klassificering av gotländska ytvatten enligt ramdirektivet för vatten
In this study the practical work with the EU Water Framework starts on the island of Gotland. 33 lakes and 32 streams have been characterized and classified regarding to their ecological status. The aim with the characterisation is to create a uniform discription of all waterbodies and a comparable estimation for the future. The aim with the classification is both to study the waterbodies ecological status and to gain knowledge of where the resources should be concentrated so that the ecological status in all waterbodies will be good in 2015.The characterisation has been done according to the EU Water Framework Directive, and the factors that have been applied are the mean depth and area of the lake. The length and size on the catchment area are the factors that have been used on streams.
Dynamisk massbalansmodellering av fosfor i Östersjön
During the past few years a vast amount of research has been done to increase the understanding of the complex ecosystem of the Baltic Sea. Modelling and simulations are important tools to increase knowledge of the system. A suitable model must be simple to use and the parameters and variables needed in the model must be easy to access.In this paper a dynamical mass-balance model, CoastMab, which is validated for smaller coastal areas, has been used to predict concentrations and transports of phosphorus in three large coastal areas - the Gulf of Finland, the Gulf of Gdansk and the Gulf of Riga. CoastMab uses ordinary differential equations to regulate inflow, outflow and internal flows. To reflect seasonal variations in temperature and different types of flows the model has a temporal resolution of a month.
Miljöutredning för Bräcke Diakoni
The environmental work in Sweden has developed a lot over the past fifty years. Today, most companies have some kind of environmental work. Environmental activities are regulated by the Environmental Code, which applies in parallel with other laws. This report is an environmental review for Bräcke Diakoni. The report aims to find out how much environmental impact Bräcke Diakoni has.
Framtidens gymnasieskola - En styrning utifrån ett modernistiskt eller senmodernistiskt perspektiv?
This empirical work and base has been to analyze the new high school reform that the Swedish government introduced as a statement 2008/09:199 about: Higher demand and quality within the high school. This statement became legal through the government vote in spring 2010. But above all it is the investigation (SOU 2008:27) that is the central piece for these new examination changes for high school students that will come into effect 1 of July 2011. The purpose and questions asked in this analyze has been if the reform takes its base in a modernistic (traditional) way or a late modern scientific perspective. And also to find out how these new quality amendments in the investigation makes visible about the high school and what the purpose are about the changes. When scientific theories in these analyze is placed against the reform, the result shows that the modernization process reflects more of a late modern aspect, which constantly reappraise in a changeable society.
Kvalitetsarbete i grundskolan ur ett specialpedagogiskt perspektiv - en fallstudie
Abstract
Heléne Slivka (2013). Kvalitetsarbete ur ett specialpedagogiskt perspektiv
? en fallstudie.
(Quality assurance process in the elementary school from a special education perspective ? a case study.)
The research
This essay investigates the language in the school´s quality assurance documents. An important aspect of this is the way in which language structures and informs how we think about, and work with, students with special needs.
Aim
The aim of this essay is to problematize how students with special needs are represented in the quality assurance documents of the school. The writer intends to point out how the ways in which the language used to describe students informs governing processes.
Skadliga nollflödespunkter i Fortum Värmes fjärrvärmenät i Stockholm : En analys av dess förekomst och effekter
When several production units provide a district heating network, water is pumped from different directions. When the flows from the plants finally meet in the network, the water can be completely still. These places are called zero flow zones. In district heating networks with several plants, which also have different supply temperatures, large and frequent temperature fluctuations can occur when the zero flow zones move. This may cause wear on the pipes, a phenomenon called low cycle fatigue.For this reason it is important to examine where and when zero flow zones that cause temperature changes occur.
Ip-telefoni med Skype som ett alternativ till PSTN för privatanvändare
The project is a practical and theoretical test of IP telephony with Skype in order to form a base for a comparison between IP-Telephony with Skype and the Public Switched Telephony Network (PSTN). PSTN is the common standard that most of us use for telephony today. The objective for the study is to simplify the choice between PSTN and IP-Telephony for the Swedish private customer user group. The project is supposed to answer the following questions. - How easy is it to start using IP-telephony with Skype? - How is the quality of IP-telephony compared to PSTN? - Are all services provided by PSTN available and accessible using the IP-solution? - How are the usability and the availability of support with IP telephony? - Is IP-telephony a cheaper solution and in that case under which circumstances? Within the project a collection of practical and theoretical tests have been performed to be able to form an opinion on the IP-solution in the following areas, installation, function, quality, usability, costs, accessibility and security.
Stubbtransporter och bränslekvalitet hos stubbved :
Stump wood is a hot alternative when the heating plants demands more and more forest fuel. The aim with the study has bean to calculate the costs in four different systems for transportations of stump wood, examine if there are any differences in fuel quality for the stump wood in the different systems, analyse if the fuel quality in stump wood is affected with the time it lays by the road side and how much space the stump wood demands on the road side. To calculate the costs for the different systems a system analysis was carried out, where some of the costs were collected through field studies on Holmen Skog stump experiment and other costs were collected from literature and contacts. Data for the fuel quality study was collected from Eons heat plant in Norrköping. Data for the study of how much space stump wood takes along a roadside was collected from field studies.
vindkraftens påverkan på elkvaliten
This thesis concerns how the power quality in the grid is affected by the connection of wind power plants. As things are at present, Fortum Distribution AB has a number of wind turbines and wind parks connected to the own grid. As the pressure on building and connecting additional wind power is increasing, so is also the interest of how the already existing wind power generation affects the power quality in the nearby distribution grids. The study is performed by direction of Fortum Distribution AB and is limited to the 10 kV/40 kV-grid in Bohuslän, Sweden. The methods for calculation of power quality are compared to the results of a number of measurements.
Interiörens påverkan på tjänstekvalitet inom tjänsteföretag: en fallstudie på caféer i Skellefteå
The purpose of this thesis was to examine café owners perception of customers expectations and what they think the interior means to the service quality. It also aims to examine how café owners use the interior to create service quality. In order to examine this, a case study was conducted based on interviews with two café owners. The study showed that the café owners take the customers expectations into consideration. It showed that they think the expectations were affected by which purpose the customer had with their visit.
Utvärdering av viabilitet hos selekterad hingstsperma med hjälp av fluorometri :
There is considerable variation between stallions in semen quality and fertility due to the fact that selection of stallions for breeding is not based on fertility or semen quality but on performance. The increasing use of cooled semen for artificial insemination has resulted in decreasing pregnancy rates. Therefore the equine breeding industry needs new methods for evaluation and development of sperm quality and fertility. This study is a part of such a project and is performed by SLU in cooperation with Flyinge AB. Ten stallions at the Flyinge National Stud were used in the study and three ejaculates were collected from each stallion.
Klosjukdomar hos hund : en litteraturstudie och en fallstudie i den Svenska Riesenschnauzerpopulationen
Various problems with nail disorders have been noticed in the Swedish population of Giant Schnauzer, but the frequencies of these problems are unknown. This could be due to the fact that bad nail quality has several differential diagnoses and lack of diagnostic criteria and diagnostic codes for nail disorders. The main purpose of this study is to review different types of claw defects and diseases of the nail bed in dogs, and to classify and evaluate the proportions in the Swedish Giant Schnauzer population.
The nail is a specialized part of the skin. The quick will strengthen and protect the third phalang against the surrounding.