Sök:

Sökresultat:

271 Uppsatser om Snow layer - Sida 2 av 19

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.

Merkostnader med vinterväghållning för Grot-transporter orsakade av väglagring.

Fuel wood is currently the third largest assortment from the forest in Sweden after pulpwood and lumber. Branches and tops i.e. logging residues are one of the assortments of fuel wood which is a common by-product after harvesting nowadays. The way to utilize, disintegrate and transport the logging residues varies between northern and southern Sweden. Branches and tops are collected throughout the year at appropriate stands, but are consumed mainly wintertime.

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.

Nedfästning av oljemåleri på puts.En fallstudie från salongen på Mostorps slott i Halland

This thesis, designed as a case study, is about complications concerning conservation of a decorative oil paint on lime plaster from the drawing-room in Mostorp castle sited in the county of Halland in south-west of Sweden. The building was built 1878-80 with an exterior of granite. The interior walls were made of clay bricks, lime mortar and lime plaster. The oil paint is applied to a layer of putty. The combination of different materials, which are organic and inorganic, affects the movement caused by internal and external stress.

Energieffektiv design av ett inbyggt flashminneshanteringssystem

The report is the result of a master thesis at ENEA AB during the fall of 2009. Itaims to create a specification of flash memory management system which focuseson power efficiency and low RAM usage for embedded systems, and to design andimplement a prototype of such a system to facilitate further development toward thecreated specification. The system used by ENEA today is a Flash Translation Layer(FTL). It has a complex structure which prohibits modifications and customization,therefore a new flash memory management system needs to be developed.The suggested solution uses a translation layer called Metadata FTL (MFTL), wherefile system metadata and userdata are separated from each other in order to improveperformance. The partition holding userdata uses a block-level mapped translationlayer system called Fully Associative Sector Translation FTL.

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.

Geokemin inom osorterade cirklar : Analys av tungmetallers distribution inom jordprofiler tagna från Abiskoområdet, nordvästra Sverige

The Arctic region appears as a pristine remote environment, yet there is increasing evidence that it is greatly impacted by pollution such as lead (Pb) and mercury (Hg). In this environment deposition of Hg has increased threefold since the last industrial revolution. In this study five cryosolic soil profiles within non-sorted circles (NSC) in the Abisko region, northwest of Sweden, has been analyzed to improve our understanding regarding how pollutants are distributed within such type of soil. The soil samples have been analyzed with the use of X-ray fluorescence analysis (XRF), for the measurements of the total concentrations of e.g. lead (Pb) and zirconium (Zr).

En jämförelse avseende beståndsgående-och stickvägsgående gallringsmaskiner

The purpose of this report is to investigate and compare the difference between stand-thinning machines and strip-road thinning machines, and how they affect the stand on behalf of future growth, theoretical economic result, wind impact, snow pressure and density of stand. The investigation is regarding the first commercial thinning of pine stands, after pre-commercial thinning that was well conducted. The investigation area was located near Katrineholm, Sweden. The measurements that were measured were strength of thinning and amounts of wind throws, snow-breaks and hauling damages. The results that emerged, was that thinning with strip-road machines had a significantly higher strength of thinning over all, as compared with the stand- thinning machines (45 percent versus 30 percent). Comparisons between wind-throws, snow-breaks and hauling damages of the stand could not establish any significant differences between the two methods that were investigated. Conclusions, over all, were that if forest owners want to have more timber volume left for second thinning and final cut of the stand, the forest owners should choose the method with stand-thinning machines. From the point of view of gentle treatment of the stand and ground damages the choice should be the same. However, the method with strip-road thinning machines is the most common and accessible method in Sweden. Most likely it is the most economical way to manage the stand for forest owners in present time. If the method with stand-thinning machines is becoming more common in Sweden, it is suggested for forest owners to consider the stand-thinning method as a candidate for treatment due to economic aspects..

Betydelsen av hästens hud och päls för reglering av kroppstemperatur i kyla ? vad händer vid klippning och täckning?

The horse is a homeothermic animal and to keep a constant body temperature in winter season is important. Acclimatisation is to provide means for a good thermal insulation consisting of skin, hair, and an outer air layer. The skin covers the horses body and it is composed of three main layers where the top layer of the epidermis consists of dead keratinized cells that are constantly being sheed. The dermis is composed of collagen connective tissue that give the skin its strength. The bottom layer with subcutaneous fat provides a thermal insulation and can be used as an energy reserve in cold weather.

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.

Kartläggning av snökanoner över Östersjön

Convective snowbands is a weather phenomenon that is associated with heavy snowfall in a limited area. They are formed over ice-free parts of e.g. the Baltic Sea when there is a cold easterly airflow over relatively warm water. These convective snowbands can cause large amounts of snow along the Swedish east coast, often causing traffic hazards. Sometimes they can even paralyze an entire community.  In this study, convective snowbands that have formed over the Baltic Sea during the period 1980-2009 are examined, in order to find out how often they occur, what place they are most common and in what month they usually appear.

Skillnader i kungsörnens (Aquila chrysaetos) flyttningsmönster beroende på ålder och klimatfaktorer : En studie för skyddet av kungsörn

This study examines the factors that influence the seasonal movements of Golden Eagles (Aquila chrysaetos), and can thus provide important information that helps to improve the protection of the species. There were two main purposes of this study. First, I wanted to analyze the difference between preferences of juvenile and adult Golden Eagles in their choice of southern or northern hibernation areas. Do younger eagles prefer moving longer distance to southern areas of Sweden? Second, I wanted to investigate how the climate influenced the choice of date of migration in the fall.

Representativitet av snödjup vid marktemperaturmätningar under snö för permafrostmodellering i området kring Tarfaladalen, norra Sverige

Snö och permafrost är två interagerande komponenter i Kryosfären. Studien undersökersnödjupets representativitet vid marktemperaturmätningar under snötäcket (BTS) föridentifiering av permafrost i Tarfala, norra Sverige. Snödjupsmätningar har utfördes itvå korsande 20 m transekter i nordsydlig (NS) samt östvästlig (ÖV) riktning utifrån enBTS-punkt. Totalt har 37 BTS (snödjup > 80 cm) med tillhörande snödjupsmätningarregistrerats och analyserats. Snödjupet varierar både lokalt kring mätpunkten ochregionalt i mättransekter men är ändå ett representativt snödjup för en punkt.Representativa BTS, sett ur ett snödjupsperspektiv, bör registreras på platser medmåttlig snödjupsvariation som på platser med homogent markunderlag, vindskyddadeområden, lä bakom ryggar och sluttningar vinkelräta mot den dominerandevindriktningen.BTS provplatser bör också ta hänsyn till de mest förekommande klasserna avparametrarna altitud, sluttning och slutningsriktning för att erhålla representativa BTS.Detta baserat på jämförelse mellan två strategier för insamling av BTS genompermafrostmodellering mellan två dataset.

En social rörelse och finanspolitiska problem : En studie av två grupper inom Occupy-rörelsen

I dagens värld har länder ett tätt sammanlänkat ekonomiskt samarbete. Detta innebär att ifall ett land drabbas av en finanskris, kommer även andra länder att falla likt dominobrickor, in i en väntande finanskris. Just detta skedde år 2008 och 2011, då ett flertal av världens länder drabbades av en stor finansiell kris. I skuggan av dessa kriser växte en social rörelse fram vars syfte var att uppmärksamma människor om vad som, enligt rörelsen, egentligen hade hänt. Rörelsen som växte fram är känd som Occupy-rörelsen.

Gaspotentialen i en deponi, idag och i en framtid :

Deposited waste material degrades within a short period in anaerobic environments. The methane gas that is formed provides a harmful contribute to the greenhouse effect, 23 times larger impact than carbon dioxide. It is therefore desirable to minimize the emissions of methane gas from landfills. This may be achieved by drain the landfill of gas. In this thesis the amount of produced methane gas at the landfill at Örebro has been calculated. Estimations have also been made of the amount of methane gas that might be produced in the landfill in the future.

<- Föregående sida 2 Nästa sida ->