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1668 Uppsatser om Automatic snow depth measurements - Sida 4 av 112

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.

Mätmetoder och nyckeltal: en kvalitativ studie om hur bibliotekschefer mäter bibliotek

The aim of this master?s thesis is to examine how managers in some public libraries are using performance measurements and to what extent decision making is based on the results. The main questions posed are:??What performance measurements and indicators are used in the libraries examined???What is the attitude towards performance measurements among library managers???How and to what extent are performance measurements and indicators used in the process of decision making???What improvement would library managers wish regarding the development of performance measurements in public libraries?The theory is based on a model of evaluation of the public sector in addition to general steps of evaluation of quality and performance measurement results. The investigation is based on qualitative interviews with seven managers of public libraries in Sweden.

Ett mät- och reglersystem för temperaturkompensering

An automatic control system for calibration of pressure indicators has been constructed. This control system can be used as a complement to the calibration system located at AerotechTelub, division MainPartner, in Linköping. The calibration system used today contains some not wanted pressure changes, which is compensated by hand today. The new system presented in this report automates the calibrating process and simplifies the calibration. Suitable hardware as motor, controls card and so on have been found and software in the form of Visual Basic program has been developed.

The effect of social rank on milking and feeding behaviour in automatic milking system for dairy cows

Today automatic milking systems (AMS) are growing in popularity. In these systems the cows are loose and have to get to the robot and the feed on their own. The cows ranking in this system affect their welfare. In this study data from seven years in an AMS was used and analysed. The aim was to investigate how ranking could affect the behaviour of the cows at milking and at feeding.

Brunnsviken : Utvärdering av åtgärder för förbättrad vattenkvalitet

Periods of hypoxia are a recurring issue in Brunnsviken. Main factors that trigger hypoxia in Brunnsviken are eutrophication  due to anthropogenic emission of nutrients, stratification in the water column due to salinity and temperature differences  that prevents mixing and a sill inlet that prevents water exchange. As an attempt to improve the oxygen levels, bottom water is pumped from Brunnsviken causing aerated surface water to flow back into the basin.  The objective of this Master?s thesis was to study the change in dissolved oxygen levels due to pumping.

Utvärdering av strömmätningar vid Höga Kusten : Strömmars betydelse för lokalisering av odlingslokaler och utformning av kontrollprogram i kustområden

A study was made to evaluate how current measurementscould help to determine how particles from fish farms are dispersed. During sixweeks of the summer 2012, two different current measurements were conducted.One of them consisted of measurements each fifth minute at 5 m and 15 m atthree locations for 14-16 days each. The other consisted of profilemeasurements at each location at four times during the period of six weeks. Forthe current measurements two instruments (model RCM 9) were used. A two weekmeasurement can give enough data to make an evaluation of how the currents at alocation will transport litter from a fish farm.

Betydelsen av skogens ålder och förekomst av lavar för renars val av vinterbetesområde :

This is a study on winter groups, ?siida?, of semi-domesticated mountain-migrating reindeers that move to lichen pastures in the lowland boreal forests during winter. The aim of the study was to determine reindeer habitat use in their winter ranges in a managed forest landscape. The reindeers use of three different types of forests was determined, 1) 100-130 year old, 2) 20-40 year old forest and 3) clear-cut areas. All sites were dominated by Scots pine, Pinus sylvestris, and had the same types of ground vegetation.

Effekt av sönderdelningsgrad och planteringsdjup på uppkomsten från rhizom av Tussilago farfara :

Tussilago farfara, coltsfoot, is a troublesome perennial weed with deep lying rhizome, which can vegetatively generate new plants. The mechanical control of coltsfoot that is used today, "starvation", which consists of several cultivations of the soil, which fragmentises the rhizome. This results in production of new shoots, which leads to depletion of nutrient resources; as long the new plant is not allowed to establish. However, very little research has been done to investigate how the starving technique affects the regenerative ability of coltsfoot. The purpose of this experiment with coltsfoot was to investigate how fragmentation and burial depths affect the time of emergence, number of emerged shoots per rhizome fragment, number of shoots per node, and if the germination ability within nodes changes during the experiment.

Introduction of heifers to an automatic milking system

Automatic milking systems (AMS) are part of a growing trend in Sweden and the number of milk-producing farms is decreasing rapidly. One main reason for the AMS is its ability to facilitate work for the farmer. The effects of introduction prior to calving have not been documented earlier and farmers are not in agreement, however they seldom see a problem with the introduction. The aim of this report is to find differences between two groups of heifers, where one group is trained i.e. introduced to the AMS before calving and the other group is introduced after calving.

Bättre åtkomst till avverkningstrakter med anpassat marktryck från avverkningsmaskinerna

The global climate-change means increasing mean-temperature and higher precipitation in Sweden, which leads to shorter periods of frozen ground in the forest. At the same time the harvesting machines are getting bigger and more powerful. The forest industry aim at an even wood flow, and the ground damage has to be as low as possible. The two biggest causes for ground-damage is the bearing capacity of the forest ground and the ground-pressure of the harvesting machines. The aim of this study was to find out some rules for the machine choice considering ground pressure, when harvesting on ground with low bearing capacity.A field study, using a Valmet 890.3 forwarder, was carried out where different ground pressures and their effect on the ground were tested on two different types of ground.Additionally, an inventory of damaged harvesting grounds was made.

CFD-simulering av kallras från fönster : Konvektorers och nischdjupets inverkan på lufthastigheter i rummet

During cold winter days it is likely that people in buildings with older windows or high glass facades experience thermal discomfort due to cold air down draughts. Earlier work has been aimed at finding analytical methods to predict the speed of the airflow in a room and in practice heating appliances are often placed beneath the windows to reduce the draught along the floor. In a study from 2012 Mohammad Parchami developed a method for estimating the required heating power to counteract the downdraught with such heating appliances. In this study, Computational Fluid Dynamics (CFD) was used to evaluate the usefulness of Parchami?s method and also to examine the potential of adapting the depth of the inward window sill as a means of decreasing the down draught.

Koffeins påverkan på osmolariteten i tårfilmen

Purpose: The purpose of this study was to investigate if there was a difference in the tear film?s osmolarity before and after drinking coffee. 'Method: All subjects in this study were asked to fill in a questionnaire to diagnose factors in their subjective symptoms, the questionnaire TERTC-DEQ. The subjects with a total graduated points of over 17 were not allowed to participate in the further measurements. In the study there was a total amount of 38 subjects, were 5 participated twice for both measurements, coffee and water.

Framtagning av prototyp till IT-baserad mobilapplikation för reseledare

Syftet med detta examensarbete är att ta fram en prototyp för en IT-baserad mobilapplikation för reseledare på resebolaget Rollin?Snow AB. Prototypen har tagits fram med hjälp av en användarstudie som följts upp med en utvärdering.En användarstudie görs för att systemet ska vara användarvänligt för användaren så att denne kan på ett effektivt och tillfredställande sätt utföra specifika uppgifter. Vår användarstudie bestod av intervjuer med reseledare från Rollin?Snow.

Bluetoothlänk mellan PC och CAN

In order to measure the quality of the logs, one can with help of Fast Fourier Transform technique get the signals resonance peaks. With help of these peaks you can see whether the quality of a tree is good or bad. This report contains the work of a where a program has been developed to be able to process a vibration created by an automatic hammer hitting on a log of wood. From the processed signal the program should be able to show both the raw wavesignal and the processed measured data from the resonance peaks. Beyond the raw wavesignal and resonance peaks the program should also be able to control the automatic hammer.

Hantering av specialservice för DHL

In order to measure the quality of the logs, one can with help of Fast Fourier Transform technique get the signals resonance peaks. With help of these peaks you can see whether the quality of a tree is good or bad. This report contains the work of a where a program has been developed to be able to process a vibration created by an automatic hammer hitting on a log of wood. From the processed signal the program should be able to show both the raw wavesignal and the processed measured data from the resonance peaks. Beyond the raw wavesignal and resonance peaks the program should also be able to control the automatic hammer.

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