Sök:

Sökresultat:

219 Uppsatser om DSC - Differential Scanning Calorimetry - Sida 4 av 15

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.

Efter förvaltningsbiblioteket? En granskning av omvärldsbevakningen vid centralförvaltningen för Landstinget i Kalmar län

The aim of this Master?s thesis is to examine the environmental scanning by the employees and politicians at the central administration at the County Council of Kalmar län. The background of the study is the closing of the administration library in January 2003, which gave more tasks to the hospital libraries of the County Council.The main questions of this study concerns the information needs of the employees and politicians, what electronic sources they prefer to use to satisfy those needs and if they are experiencing a need for more support and help, from a librarian or by the development of a common catalogue of hyperlinks. All 104 persons in the population were asked to answer a questionnaire on the Intranet. The task was performed by 60 persons.

Punktmolnshantering i anläggningsprojekt : Utvärdering av programvaror för framtagande av markmodell

An increased number of participants in the construction industry is asking for accompanying terrain models to the project in order to get a better understanding of the field. When the desire to create buildings that fit together nicely with the surrounding area is increasing, it becomes more and more important to have a broad base of knowledge about the ground on which the building is to be erected. Terrain models are also very useful in the planning of logistics, documentation for landscape architecture projects, and billings for mass calculations.Surveys for creating terrain models can be performed with laser scanning. The advantage of laser scanning is the time-effective surveying, the detailed information as well as the ability of application in complex environments resulting in a cost-efficient project. With this in mind our thesis was defined in collaboration with the company Bjerking AB in Uppsala in order to investigate if there were any softwares suitable for terrain modeling.

Hematologiska analysinstrument för mindre djurkliniker : en utvärdering av QBC-V och Scil Vet abc för analys av prover från hund och katt

Two haematological instruments intended for small animal clinic use were evaluated at the Department of Clinical Chemistry, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden. The QBC-V and Vet abc were compared to a reference instrument, the Cell-Dyn 3500. Fresh blood samples were obtained from canine and feline patients from the University Veterinary Hospital, SLU. The QBC-V was used for 111 canine samples and 78 canine blood samples were analysed with Vet abc. From cats, 23 samples were analysed with both instruments.

Måltidsmönster, kost - och - medievanor bland överviktiga 15-åriga flickor och pojkar

Objective: The aim of this study was to compare equations used to calculate BMR to values of BMR obtained from measurements in order to determine the most suitable equation to be used on children and adolescents with CF.Design: The participants where children and adolescents with CF. Data was collected from the division of Clinical Nutrition at Uppsala Akademiska Sjukhus. Age, weight, height, BMI, BMR, FFM and FM was recorded from 27 measurements. BMR from the participants collected from the indirect respiratory calorimetry was compared to the results obtained from five equations used to obtain a calculated value of BMR.Results: Tverskayas equation was best correlated with the measured BMR for the whole group. The equation underestimated BMR for the participants with a measured BMR over 1400 kcal/24h and overestimated BMR for participants with a measured BMR under 1400 kcal/24h.

Identifiering av röjningsbestånd med hjälp av flygburen laserskanning

Bergvik Skog is one of the leading forest companies in Sweden who use airborne laser scanning for forestry information. They utilize laser data retrieved by the Swedish National Land Survey to describe the forest holdings and facilitate planning for thinning and final felling operations. However, the possibility to identify stands with clearing needs by using laser scanning data has not been tested in a large scale. The data used in the current study are field data from The Swedish National Forest Inventory in combination with laser data from the Swedish National Land Survey acquired in 2009. The collected data is used to find one or several laser variables that best describe the relationship of the field measured samples with clearing needs.

Områdesinbäddning för ODE

This paper gives an introduction to the theory of minimal surfaces. It is in- tended for undergraduate students with some basic knowledge of differential geometry and complex analysis.After defining the concept of minimal surface and giving a brief histo- rical survey, we look at some well-known minimal surfaces and a few of their characteristic properties. The connection between minimal surfaces and harmonic functions is discussed and the Weierstrass-Enneper represen- tation formulas are introduced. We also present Bjo?rling?s problem and give some examples. .

En utredning av tekniken "mobile mapping" i kommunal verksamhet

This thesis work is intended to analyze whether the municipalities has a need for the new technology of mobile mapping.Mobile mapping consists of the technologies of laser scanning, photographing and positioning of streets and roads in city environment and in the countryside. When these technologies are operating together a georeferenced three-dimensional image model is created, which has specific coordinates that states its position on the surface of the earth. Thanks to the laser scanning process even measuring can be performed in this model.The municipal sector consists of many different departments which use visual spatial information. These departments are an interesting target group for this system. Specific departments within the municipal sector, which we considered were the most suitable, have been selected.

African swine fever in Uganda : description of a recent outbreak and possible differential diagnoses

This study had two different aims. The main aim was to investigate the dynamics and impact of African swine fever (ASF) on a farm in Uganda during a recent outbreak through a case study. The second aim was to estimate the presence of two important differential diagnoses of ASF: Classical swine fever (CSF) and Porcine Reproduction and Respiratory syndrome (PRRS).The field and laboratory based case study of the farm level dynamics of ASF virus during a recent outbreak (October-December 2010) on a farm in the district of Mityana, Uganda, was conducted, using interviews, ELISA and RT-PCR. The financial impact on the farm was also estimated. The impact of the outbreak was profound.

Klassning av fjällbjörkskog enligt FAO:s definition av skogsmark med hjälp av flygburen laserskanning

Sweden?s forestry legislation was updated in 2010 and a new definition of forest land was introduced. This definition was adapted to the one used by the Food and Agriculture Organization of the United Nations (FAO) for international statistics on the state of the world's forests. It is in short based on the lands ability to grow forest that reaches 5 meters, 10 % canopy closure and has a continuous distribution, according to FAO at least 0.5 hectares. A country-wide laser scanning is now carried out for the production of a new national elevation model; the laser data also provides information on forest height and density.

Undersökning av tidstrender i registerdata. Lungcancerregistret ROC.

This paper gives an introduction to the theory of minimal surfaces. It is in- tended for undergraduate students with some basic knowledge of differential geometry and complex analysis.After defining the concept of minimal surface and giving a brief histo- rical survey, we look at some well-known minimal surfaces and a few of their characteristic properties. The connection between minimal surfaces and harmonic functions is discussed and the Weierstrass-Enneper represen- tation formulas are introduced. We also present Bjo?rling?s problem and give some examples. .

Basal prediktionsmodell för graviditet vid in-vitrofertilisering

This paper gives an introduction to the theory of minimal surfaces. It is in- tended for undergraduate students with some basic knowledge of differential geometry and complex analysis.After defining the concept of minimal surface and giving a brief histo- rical survey, we look at some well-known minimal surfaces and a few of their characteristic properties. The connection between minimal surfaces and harmonic functions is discussed and the Weierstrass-Enneper represen- tation formulas are introduced. We also present Bjo?rling?s problem and give some examples. .

Kontrollerad gjutprocess för renare stål

In a multi-year project at Swerea Swecast AB studies on influence of dissolved gas on inclusions have been made. The knowledge about these parameters could be used to increase the quality of the final steel casting. The purpose of this thesis was to closer examine the impact of the oxygen level on inclusions.The questions asked were:? What was the amount of inclusions at different levels of oxygen?? What was the size of these inclusions at different levels of oxygen?? What does the inclusions consist of at different levels of oxygen?This was studied by measuring and sampling, sample preparation and microscopic analysis using an optical microscope and a scanning electron microscope (SEM). Measurements and sampling was performed at Smålands Stålgjuteri AB in Eksjö and at Swerea Swecast AB in Jönköping.

LiDAR-bildanalys av flutings i södra Norrbotten : Kartering och datering av avvikande isrörelseriktningar

The aim of this study was to map and date glacial flutings with ice flows deviating from the predominating northwesterly ice flow direction in the southern part of Norrbotten County in northern Sweden, and also to investigate if parts of the glacial landscape are older than previously thought. The traditional view is that most landforms in the area were formed during the late Weichselian (W3). Analysis of the new high resolution elevation model (2 m grid) derived from laser scanning was performed after treating the data with a hillshade tool in ArcMap to reveal terrain features such as flutings. The analysis resulted in a map showing four main groups of deviating ice flows (N-S, NO-SV, SO-NV and S-N) and several westerly ice flows. The majority of flutings with deviating ice flows were found in low terrain.

Minimalytor och Björlings problem

This paper gives an introduction to the theory of minimal surfaces. It is in- tended for undergraduate students with some basic knowledge of differential geometry and complex analysis.After defining the concept of minimal surface and giving a brief histo- rical survey, we look at some well-known minimal surfaces and a few of their characteristic properties. The connection between minimal surfaces and harmonic functions is discussed and the Weierstrass-Enneper represen- tation formulas are introduced. We also present Bjo?rling?s problem and give some examples. .

<- Föregående sida 4 Nästa sida ->