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132 Uppsatser om Runoff coefficient - Sida 5 av 9

Varför svänger stenen? : En studie i curlingens komplexa tribosystem

The tribo system ice-curling stone was investigated in order to understand the mechanisms behind the stones' behavior on the ice sheet. The problem with non-identical stones should also be addressed.The stone curls, that is, its sliding path deviates from a straight line to the right for a clock-wise rotation and to the left for a anti-clock-wise rotation. Several mechanisms to explain this behavior have been proposed over the years but none has been successful.By carrying out experiments at the local curling rink and studying silicon castings of ice- and stone-surfaces with scanning electron microscopy and vertical scanning interferometry, it has been decided that the curl is not due to dry friction, ice-debris or the difference in friction on the left and right side of the stone. The side force comes from the fact that the friction is higher at the back of the stone than at the front.The contact between stone and ice is never completely dry, nor in the hydrodynamic lubrication regime. It is probably a combination of hydrodynamic lubrication and a contribution from mechanical scratching of the ice.

Effektivisering av urvalsprocesser vid analysering av björnspillning : Ett förslag till den svenska förvaltningen av brunbjörn Ursus arctos

The aim with this report is to formulate a strategic method to optimize selection processes of DNA-samples from a faeces inventory to identify as many individuals in as few analyzes as possible, and by that keep down the costs of brown bear management. Brown bear management in Sweden founds today on results from faeces inventory and is substantially led by the county administration boards. Data from the years of 2004 and 2009´s inventories in Västerbotten was used to test and evaluate different methods in selection processes of which faeces that should be sampled. Comparison were made between making selection by chance, by spatial distribution and by calculating variations in logistic regressions coefficient b, in other words bear density and probability in finding same individual in several faeces. We can show making selection by chance is the most uncertain method.

Fosforförluster från lantbruket och dess bidrag till övergödning av sjöar och vattendrag i Växjö kommun

The possibility for plants to utilize phosphorus in soil is a prerequisite for conducting agricultural production, both small scale and professional. Spreading of phosphorus fertilizers and manure is therefore seen as a necessity in today's agriculture in order to achieve high yield. Manure management, livestock farming and manure storage could contribute to the eutrophication of lakes and rivers. For instance, when the ground becomes saturated, phosphorus leakage could be seen in surface runoff or in point sources resulting from inadequate manure storage management.In the municipality of Växjö there is still many bodies of water that do not reach the Swedish environmental water quality standard of "good ecological status". This thesis has therefore analyzed the manure management and storage on agricultural farms which may have contributed to eutrophication in the municipality.The method for this thesis was a literature study, a questionnaire survey with 820 receivers and a summary of issued inspection reports from 2013.The results highlight the ways in which agriculture may have contributed to the eutrophication of lakes and streams in the municipality of Växjö.

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.

Förändring av nitratläckage och växtproduktion från låglänt jordbruksmark vid en ny reglering av vattennivån i Mälaren

The water level of Lake Mälaren has been regulated since the 1940?s. A recentinvestigation suggests that the current regulation needs to be adjusted in order toprevent a decline in water level, salt water from infiltrating from Lake Saltsjön,and risk of floodings. In addition to these preventions, the new regulation couldpotentially effect the natural environment and agriculture practices in the lowlands that surround the lake. The new regulation proposal calls for an increase invariations in Mälaren?s water level during seasons, while the annual mean waterlevel will remain the same.

Fönsterutredning för radhusområdet Skeppsvägen

Mitt examensarbete innefattar en fönsterutredning för radhusområdet Skeppsvägen i Bålsta. Fastighetsägare är Håbohus AB och examensarbetet har skrivits för Skanska Sverige AB. Arbetet har skrivits på plats i Bålsta där Skanska Direkt AB har eget kontor och erhåller idag totalentreprenaden för renovering av Skeppsvägen. Arbetets syfte är att klart och tydligt redovisa eventuell effekt och energibesparing vid byte av befintliga fönster och altandörrar.Undersökning av fönster och altandörrar har gjorts okulärt, med värmekamera och med fuktkvotsmätare. Vid den okulära besiktningen noterades färgsläpp på fönster.

Kadmium i skånska vattendrag : en metodstudie i föroreningsmodellering

Modelling of pollutants is commonly used in research and at departments working with environmental issues. The need to use large amounts of data when modelling creates the opportunity for more generalised models with lower data demands. Aggregating functions into coarser elements is a sort of generalisation of actual features in nature.A development of a method and a modelling tool called ?KadmiumKalkylatorn? has been performed to model cadmium pollution in rivers in Skåne, Sweden. The water runoff has been multiplied with cadmium standard concentrations based on membership in landuse classes.

Termoelektrisk lagring i system med fjärrvärmeproduktion

With increased deployment ofintermittent renewable energy, such aswind and solar power, energy storagebecomes necessary to help reduceproduction peaks. Thermoelectric EnergyStorage is a method still in researchphase, which stores electricity in hotwater at a temperature of 120 ° C. Thisthesis aims to examine whether theThermoelectric Energy Storage would bepossible to integrate into existingpower generation such as a combined heatand power plant, and how the technologypotentially could function in theelectricity market. ThermoelectricEnergy Storage consists of a chargingprocess and a discharging process, bothoperating by the working fluid CO2. Toincrease the efficiency of theThermoelectric Energy Storage, wasteheat from the district heating networkis integrated.A model of the Thermoelectric EnergyStorage has been developed and it wascalculated by thermodynamic propertiesof the working fluid, CO2, in thevarious process steps.

Experimentell konstruktion av pickupsystem anpassat för trummor med hjälp av MATLAB

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.

Äldre personers attityd till styrketräning: utformning och reliabilitetstestning av en provenkät

Syftet med denna studie var att utforma och reliabilitetspröva enkätfrågor om äldre personers attityd till styrketräning. En enkät bestående av 47 frågor och påståenden delades ut till 31 äldre (60-81 år) personer som fick besvara enkäten vid två separata tillfällen. Varje enskild fråga analyserades för test-retestreliabilitet på tre olika sätt: 1/ Intraclass correlation coefficient (ICC) 2/ Absolut reliabilitet med 80% respektive 95% konfidensnivå samt 3/ Proportion of agreement (PA) med PA% och PA ±1%. Enligt gränsvärden som sattes för acceptabel reliabilitet hade 16 frågor ett värde på ICC <0,50, 11 frågor ett pa(%) <60%, 16 frågor ett värde &lt;80% på pa ±1%, nio frågor en absolut reliabilitet av =>2,0 vid 95% säkerhet och 12 frågor en absolut reliabilitet =>1,5 vid 80% säkerhet. Dessutom visade analysen av absolut reliabilitet att det för 2/3 av frågorna krävs två skalsteg för att påvisa en skillnad vid 95% säkerhet.

Hållbarhetsredovisning : En studie av Vattenfall AB i ljuset av GRI

This essay is about democracy and how a democracy index can be used as a tool to illustratethe gap between reality and ideal. The purpose of this study can be expressed by two researchquestions: Does the Economist Intelligence Unit's (EIU) democracy index illustrate thedistance between reality and the ideal of democracy presented by Dahl? and Can the EIU'sdemocracy index be modified by a) internal adjustments and b) using the variables includedin World Economic Forum?s (WEF) equality index?By using a combination of theories (Dahl?s theory of democracy, Rawls theory of justice andchosen theories critical to liberal democracy) as an analytical framework the following twoquestions have been answered:1) Which of the variables included in the EIU's democracy index have the potential to capturethe level of political equality?2) Which of the variables included in the WEF?s equality index have the potential to capturethe degree of political equality?By using a quantitative method the study?s third and last question has been answered:3) How strong is the rank correlation between the EIU?s democracy index and the WEF?sequality index, that is; how strong is the rank correlation coefficient (rho)?The data presented by the WEF?s equality index indicate that women are systematicallydiscriminated against as a group. From a democratic perspective the EIU may need tomeasure inequalities at a group level in order to capture the lack of political equality betweenindividuals. By reformulating some of the EIU?s variables, by revising the EIU?s point systemand by using the variables included in the WEF's equality index to extend EIU?s democracyindex, the chances of capturing the gap between reality and the ideal of democracy presentedby Dahl would likely increase..

Konstruktion av formkropp pa JAS 39 E/F Gripen

The aim of this work is to develop new conceptual designs for the fairings that are situated between the fin and the rear fuselage on the new version of the JAS 39 Gripen aircraft, called the Gripen E/F. The designs presented should show a profit in the form of lower weight. To achieve weight loss, the possibilities of using other construction materials other than those which are available at Saab today were studied. Therefore, a material survey was carried out in which the market for modern construction materials was studied to get an idea of today?s level of technology.

Demokrati : En studie om demokratiindex och dess eventuella begränsningar

This essay is about democracy and how a democracy index can be used as a tool to illustratethe gap between reality and ideal. The purpose of this study can be expressed by two researchquestions: Does the Economist Intelligence Unit's (EIU) democracy index illustrate thedistance between reality and the ideal of democracy presented by Dahl? and Can the EIU'sdemocracy index be modified by a) internal adjustments and b) using the variables includedin World Economic Forum?s (WEF) equality index?By using a combination of theories (Dahl?s theory of democracy, Rawls theory of justice andchosen theories critical to liberal democracy) as an analytical framework the following twoquestions have been answered:1) Which of the variables included in the EIU's democracy index have the potential to capturethe level of political equality?2) Which of the variables included in the WEF?s equality index have the potential to capturethe degree of political equality?By using a quantitative method the study?s third and last question has been answered:3) How strong is the rank correlation between the EIU?s democracy index and the WEF?sequality index, that is; how strong is the rank correlation coefficient (rho)?The data presented by the WEF?s equality index indicate that women are systematicallydiscriminated against as a group. From a democratic perspective the EIU may need tomeasure inequalities at a group level in order to capture the lack of political equality betweenindividuals. By reformulating some of the EIU?s variables, by revising the EIU?s point systemand by using the variables included in the WEF's equality index to extend EIU?s democracyindex, the chances of capturing the gap between reality and the ideal of democracy presentedby Dahl would likely increase..

Uppföljning av planerat skotningsavstånd med hjälp av geografisk informationsteknologi (GIT)

The cost of forwarding corresponds to about one tenth of the forestry industries raw material cost. This gives a motive to do good follow-ups to get a good overview of the forwarding distance and, thus, enable improvements. Follow-ups are also justified by the possibility to make more accurate calculations of the harvesting costs, if better estimations of forwarding distance are achieved. Today (2009) Stora Enso has GPS and vehicle-computers in most of their forwarders. These are used mainly for the forwarder to follow the tracks of the harvester and for the planning leader to see how the forwarder has been driving within the stand.

Klimatskärmens funktion : En jämförande analys av projekterade nybyggnationer i Östra Salabacke, ur ett energi- samt fuktperspektiv

The design of the building envelope affects the energy consumption of a building. As the energy requirements for new buildings are becoming more demanding, the performance of the building envelope must be improved. Energy efficiency and durability are important attributes to consider.This report includes investigations of the building envelope, moisture and passive solar energy. It is based on the analysis of two different buildings with different designs. These buildings stand as reference for two of the companies who are working on a new, climate smart, residential area in Uppsala, Sweden.Studies and analyses on energy consumption and moisture transportation were made.

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