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291 Uppsatser om Drawdown of groundwater table - Sida 13 av 20

Voltage Sags Indices and Statistics

Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.

Temperaturens och den fotosyntetiskt aktiva strålningens effekt på avgång och inlagring av kol på en dikad torvjord

The decomposition of organic carbon in drained peat soils is a major source of carbon di-oxide in Sweden. A big part of these drained peat soils are used in agriculture and it is a big challenge to slow down their decomposition. It has earlier been thought that less tilling and higher water table levels would decrease the activity of soil microbes and thereby the decomposition, but recent experiments has showed that this has little or no effect. In this bachelor thesis a field experiment was made on drained peat soil with ley, outside Björklinge, Uppsala municipality, Sweden. The experiment was carried out in May 2011. The objective was to develop a method to examine how the net exchange of carbon diox-ide from plant covered peat soil is affected by temperature and photosynthetically active radiation (PAR).

Att skapa fria, demokratiska och solidariska medborgare : En essä om att granska våra normer

This essay is about power, democracy, solidarity and equality in preschool. I examine three different situations to determine if I could have acted more sensibly in my interactions with the children. I portray: a ?children?s choice meeting? where children select an activity, a so-called emotional gathering and a dialogue at the lunch table about a popular movie that we plan to watch together afterwards. The purpose of this essay is to examine which norms and values form the basis of my actions, and if so, how these lead me to use my power to shape the children.I have chosen to use hermeneutic and norm-critical perspectives where I investigate and examine my norms and values and how I react and act, both consciously and unconsciously.

Restvärmeåteranvändning från absorptionsvärmepumpar : en kartläggning av möjligheter och begränsningar vid Vattenfall Värme Uppsala Block 5

Vattenfall district Heating power plant in Uppsala produces district cooling with absorption heat pumps which leads to a large amount of waste heat that has to be cooled with evaporative cooling towers. The Environmental Court has ordered Vattenfall to survey the possibilities to recover the heat, which is the focus of this thesis.The study begins with an overview of the system, and conditions and limitations for waste heat recovery is examined. In the next step alternatives to recycle the heat is evaluated, either by direct recovering or by upgrading.First, the technical possibility of each alternative is discussed, and then the operation time and the amount of recovered heat is calculated. Those alternatives which are possible are brought further to an economic analysis.The cost of investment for each alternative constitutes the basis for a present value analysis. The results are put together in a table where the total amount of recovered heat is compared with the present value for the different alternatives.

Spännkraft på bandavskrapare : Utredning och konstruktion

This thesis was performed at Vendig AB which is a company that develops and sells products such as belt scrapers for conveyor. The thesis is divided into two parts, one part where it´s investigated which tension force is required to tighten Vendig AB´s scraper Hampus against the belt in a correct way. The second part is called mechanical design and here a new and more compact tension device is developed.Field studies has been conducted at a couple of Vendig AB´s costumers to get a knowledge base about how Vendig AB´s products are used, how they function and the environment they operate in. During one of the field studies the force between the scraper and the belt was measured. The result from the measurements, together with a report from LKAB [1], were evaluated and summarized in a table.

Regionala strategier på lokal nivå Om kulturarv- och kulturmiljöarbete i regionalt och kommunalt utvecklings- och tillväxtarbete

The following essay aims at the interplay between regional och municipal growth work, and theway cultural heritage is used in growth work strategies. The main issue has been whether theregional strategies are followed up in the municipal strategies, which has been investigated bymeans of question which impact the region?s strategies has at the local level.The essay draws upon an instrumental perspective on cultural heritage and cultural environment,here defined as instruments in the national development and growth efforts. Three publicationsthat highlights potential roles of cultural heritage and cultural environment to act as instrumentsin the regional and municipal development and growth efforts has thereby been selected astheoretical models. These roles has further been summarized in a tabular form as a schematicdivision of main themes with sub-categories, used as a framework for deciphering the regionaland municipal strategies.A content analysis of available strategies at both regional and local levels have been used as amethod for investigating the issue, where the role of cultural heritage and cultural environment(as defined in the schematic table) has guided the reading.

Multiplikationstabellen : En jämförelse mellan strategi- och repetitionsbaserad undervisning

Undervisning om multiplikationstabellen består främst av lärande genom repetition eller strategi. Syftet med litteraturstudien är att utifrån forskning undersöka och jämföra inlärning av multiplikationstabellen genom strategi- och repetitionsbaserad undervisning. Studien avgränsas till elever i årskurs 1 till 6. Materialet samlades in genom en iterativ sökning på åtta databaser för vetenskapliga publikationer. Det insamlade materialet bestod av sjutton vetenskapliga publikationer.

Utredning av fastighetsel i ett äldre och ett ombyggt flerbostadshus i Gävle

The residential and service sector in Sweden accounts for approximately 38% of the total energy usage and Sweden has an aim to reduce the total energy use by 20% by 2020 compared to 2008, which means residential sector will have to improve energy efficiency. As part of that a law was instituted by the Swedish parliament that all properties must have an Energy Performance Certificate (EPC) to thereby give the property owners a greater insight into energy use in their buildings and propose recommendations for energy-efficiency measures. On the EPC, a value on the building's energy performance in terms of energy use in kWh / m2 per year is declared, of which electricity is a share of it. Instructions on what to include in the amount facility electricity for running the facilities is regulated by the authority for building, Boverket while SVEBY has made an interpretation of the regulations in their report "Brukarindata bostäder" where they have a table on what should be included in the amount and what not to include.This report is a study of two similar apartment buildings, where one of the buildings recently underwent renovation, to see if the declared amount of energy for electricity, in the EPC, is consistent with the measured value, and whether there has been any reduction in facility electricity in the renovated building after the renovation.The result shows that the measured value of the building electricity was 2.6 kWh / m2 per year, 28,8 %, lower than the declared value in the building that have not undergone a renovation. Calculation of values from previous years (2011) by the same percentage of facility electricity as in the results of the measurements, 56.7%, it becomes clear that the declared value for facility electricity in the EPC of the renovated building do not correspond with reality and that there has been an increase in use of facility electricity after the renovation..

Produktutveckling av Mingelbord

Syfte ? Att skapa en ny produkt inom kategorin mingelbord, som erbjuder fler användningsområden för att bli mer anpassad för privatpersoner och i hemmamiljö. Att genom en innovativ konstruktion och en kombination av moduliserade- och hantverksdelar skapa en unik produkt på marknaden.Metod ? Grundmetoden för det här arbetet är den första fasen i en produkts liv: produktutvecklingsprocessen; identifiera behovet, planera designprocessen, ta fram kundkraven, utveckla konceptet och till sist utveckla produkten.Resultat ? Designkoncept på ett mingelbord har tagits fram och redovisas i bilder. Dessa bilder är resultatet av en uppmodellering i datorn med hjälp av 3D-progam.

Eutanasi : en skonsam död

This work is about euthanasia and how to use it on horses, dogs and cats. A description for each animal is done, about when it is time, why, which methods can be used and who is allowed to use them, how and where it shall be done. The methods we have concentrated on are: - Chemical destruction and the most common drugs for euthanatize horses, dogs and cats. - Physical disruption of the brain activity by a captive bolt, only for horses. The captive bolt only makes the horse unconscious and must always be followed by cutting off the vena jugularis. Then the horse dies because of loss of blood. No matter which method used for euthanizing, the animal must be declared to be dead by the operator before other measures. The testing criteria for death: muscle relaxation and cyanosis, cessation of reflex activity and pupillary dilatation, cessation of respiratory activity and cessation of all cardiac activity.

Utveckling av golvlucka för hoppgropssystem i kommunal idrottshall

In this thesis a concept for floor hatches for foam pits has been developed. Since there is an existing solution that is powered by hydraulics and is expensive, the goal was to develop a cheaper solution, as simple as possible.A number of different concepts were developed and evaluated. A concept with five sections that are pulled to the side and stacked on each other was chosen as it was thought to have the lowest risk of crush injuries and to be easiest to manage and control. In the opening behind the foam mattress a lifting table is placed to regulate the height of the stacked sections.To be allowed to be installed in the floor of sports halls the sections must be dimensioned according to the construction standards for these types of buildings. Different dimensions of beams in steel and wood materials were evaluated and of those, who lived up to the requirements of the standard, a concept was chosen.

Great design experiences don?t happen by accident - En kvalitativ studie om design av upplevelser i Surface-computing system

Användarupplevelser är en gren inom användbarhetsområdet som på senare år kommit att studeras alltmer. Orsaken till detta är att ny teknik medför andra krav på produkter än att produkter som sådana ska vara lätthanterliga. Produkten kan likväl ha som syfte att vara rolig att använda sig av.Studiens syfte var att studera användarupplevelser beträffande Surface-computing teknologi.Företaget Interactive Institutes innovativa Surface-computing produkt Virtual Autopsy Table fick exemplifiera Surface-computing teknologi i publika miljöer. Genom att använda denna uppmärksammade produkt som underlag är syftet att undersöka vilka designmoment som kan anses vara kritiska för upplevelsebaserad design. Studiens frågeställning blev:Vilka riktlinjer kan tas fram för att vägleda en designprocess att bli mer fokuserad påanvändarupplevelser vad gäller Surface-computing system?Med utgångspunkt från studiens datamaterial, så var en del av studiens syfte att ta fram riktlinjer.

MÖJLIGHETERNA MED CLUSTERED COLUMNSTORE INDEXES & IN-MEMORY OLTP

Clustered Columnstore Indexes (CCI) and In-Memory Online Transaction Processing (OLTP) are two new techniques that were introduced with Microsoft?s new database management system SQL Server 2014.The thesis analyzes these two techniques, describes the theory behind them and also the background information that needs to be known to understand more of the new techniques. Performance tests of the new techniques have been performed to see how much faster response time we can get and less storage we need to use where the result is represented by performance diagrams and a compression diagram. This thesis is a cooperative work with a company called Trimma and the result is used as support to decide if these new techniques could be of advantage for the company.The test consists of five test queries with different purposes. The result is illustrated by diagrams that show the result and another diagram that shows how much the data gets compressed with the different techniques.

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.

Utredning av Valboåsens grundvattenmagasins förbindelse med Gavleån : En analys av halten löst syre genom mätningar

Gävle kommuns VA-huvudman Gästrike Vatten AB ansvarar för dricksvattenproduktionen i Gävle. För Gävles tätort tas vatten från Valboåsen som sträcker sig från öster om staden, genom staden och vidare norrut. Denna rapports syfte är att genom mätning av halten löst syre undersöka Valboåsens förbindelse till Gavleån. Detta kommer ge en ökad förståelse för åsens komplexitet. Resultatet kommer också att användas för att verifiera och utveckla den konceptuella modellen över flödena i åsens grundvattenmagasin som tagits fram av Midvatten AB.

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