Sökresultat:
106 Uppsatser om Layers - Sida 2 av 8
Optimering av sotningsfrekvens i biobränsleeldad CFB-panna : panna 5, Mälarenergi AB, Västerås
During the past 30 years the fuels for energy production in heating and power plants
have changed. Fossil fuels have decreased in usage whereas bio fuels in Sweden
have increased with 60% since the 1970's. Different fuels affects combustion and the
release of various substances and particles into the flue gas. This is caused by the
diverse components and chemical structures of fossil fuels and bio fuels. When the
flue gas leave the combustion chamber and enters the path to the chimney particles
in the gas are being transported out of the combustion chamber.
Abrasiv nötning av polymerer tillverkade genom 3D-skrivning
Volvo Cars in Skövde manufacture and assemble Volvo engines. When attaching the ignition coil to all 4-cylinder engines, a special mounting tool is required. This mounting tool is currently manufactured from injection-molded polyoxymethylene (POM), a thermoplastic. It has been noted that the life span of the tool is shortened as a result of abrasive wear that occurs during the attachment process of the ignition coil.An investigation of the possibility of manufacturing the mounting tool with a 3D-printer is undertaken in cooperation with ÅF, a consultant to Volvo Cars. A literature study is first presented to introduce broader knowledge on the subject.
Framtida inhemska proteinfodermedel i den ekologiska fjädefäproduktionen :
Organic Layers and broilers will according to (EEG) no 2092/91 be fed 100 % organic feeds in year 2012, which is expected to present problems associated with the specific protein requirements of poultry. This document aims at describing the feedstuffs that possibly may constitute a part of the solution to these problems. Peas, field beans, naked oats, canola, hempseed and sunflower come out as interesting feedstuffs. Biproducts from the milling and dairy industry together with marine protein supplements may be brought to the fore, provided that the demand for organic products will rise further..
Framtida användningsområden för materialadderande tillverkning : En studie i hur materialadderande tillverkning kan användas i rymden
In this paper we have studied possible future uses for Additive Manufacturing (commonly referred to as 3D-printing) in Space. More specifically we have sought to establish how Additive Manufacturing can be used to construct structures on the Moon. Our studies have shown that Additive Manufacturing has great potential for establishing colonies on not only the Moon, but perhaps even further away from our home planet. With Contour Crafting-technology in combination with ISRU (In Situ Resource Utilization) we could, with material already present in the sediment Layers of the Moon, construct advanced structures without having to transfer any extra material from Earth. This would lower the costs of establishing a colony on the Moon to such extents that it could actually be fiscally possible..
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.
Årstidsdynamik för kvicksilver i ett sövattensediment :
The limit for mercury in fish, set by health authorities, is exceeded in about half of the lakes in Sweden. Methyl mercury (MeHg) is the most toxic form of mercury and accumulates in fish. Therefore transformation of inorganic mercury (Hg) to methylmercury (MeHg) is an important process that we need to understand in order to possibly counteract the negative effects of mercury in the environment.
The seasonal dynamics of mercury biogeochemistry is likely of great importance for the accumulation of MeHg in the aquatic food web. In thesis the chemical speciation and transformations of Hg and MeHg in bottom waters and sediments is followed in Ängessjön, a small lake located on the east coast in the middle of Sweden. The lake is not directly affected by any industrial pollution and concentrations of Hg in the sediment reflect the atmospheric deposition in this area, as well as processes taking place along the hydrological pathways from soil to lake.
Samples from sediment, bottom- and streamwater were collected in average every second month during the period Feb.
Ligger bäckarna rätt i kartan?
?Are the headwaters streams at the right position in the map? is a study that has been performed on behalf of Holmen Forest, region Örnsköldsvik. This study will be the basis for deciding if the Hydrology Layer Property map or Holmen Forest map will be used for planning nitrogen fertilization in forestry. The background to this study is that nitrogen fertilization near water will increase the risk of nitrogen leaching out into the water systems, which has a negative impact on the environment. The headstreams positions have been recorded in the field with a GPS and the data analyzed in the geographic information system ArcMap.
Tillämpning av nya beräkningsmetoder för branddimensionering av träkonstruktioner - analyser och jämförelser
To build high-rise buildings made of timber has for long been limited by national laws, due to the lack of knowledge in engineering solutions. Frame structures made of wood has for a long time been associated with major fire hazards and consequently lower safety and this connection is still being made today. The increased environmental awareness in recent years has contributed to the exploitation of indigenous building materials, including wood from our own Swedish forests and has become increasingly common. Increased knowledge about how structures behave in fire and how they can be protected in order to achieve safe timber structures has resulted in a growing interest in these structures in the construction industry. Research in the area is constantly updated and new laws allow any number of storeys in wooden buildings in Sweden as long as the performance requirements are fulfilled.The main part of this work has involved calculations of the fire resistance and load bearing capacity of floor and wall constructions.
EN TOTALKOSTNADSJÄMFÖRELSE MELLAN CELL-, SKUM- OCH LECA-BETONG
This report provides a comparison between the products cellular concrete, foam concrete and LECA concrete. The questions to be answered during the work is how the cellular concrete stands up in cost terms to the existing competitors on the market, how the concrete products differ in design work, and in which situations the concrete varieties are preferred to use.Cellular concrete is a variant of ordinary concrete, with the difference that the ballast is exchanged from stone materials to expanded polystyrene beads (EPS). This substitution gives a product with higher insulation values but lower weight than ordinary concrete.The work was carried out by designing a survey which was sent to two hundred randomly chosen companies across Sweden, to see the building industry?s opinion of the product cellular concrete. The survey showed that cellular concrete was equals its competitors in terms of price, while the product was said to be more flexible, quicker and easier to cast.Then some of the companies, who participated in the survey, were interviewed to see more carefully, how the price, the workmanship and the time for casting and dehydration differed between the products.
Miljöarkeologi i Umeå stads hamn och slagfältsarkeologi på Krutbrånet : Två fallstudier inom historisk arkeologi i Umeås 1800-tal
This master thesis deals with two case studies in environmental archaeology and battlefield archaeology focusing on two major events in the late history of the Swedish coastal town Umeå and its nearby village Sävar. Established in the early 1600's, Umeå was known for its export of timber and import of cereals. The town has suffered from numerous fires, the fire in 1888 being the most devastating. Few written records of the town remain from before the 1900's. The latest war in Sweden's history is documented in historical sources and took place at Krutbrånet, Sävar where the Swedish troops suffered defeat against the russian forces in 1809.
Spolmaskangrepp är ett ökande problem hos värphöns
This literature review summarizes available data on infection with the parasitic roundworm, Ascaridia galli, as a cause of disease in poultry, including the consequences of a conversion to alternative production systems. Ascaridia galli has a direct life cycle with resistant eggs that survive and are easily spread in the environment, especially in systems with bedding materials where the faecal contact is high. The infection is usually subclinical but depending on the infection dose, the symptoms range from weight loss and diarrhea to mortality. Factors such as the feed composition and genetic variation among different hybrids clearly affect the establishment rate of the infection. Ascaridia galli will probably become an increasing problem, with a shift from the traditional battery cages to alternative systems where the risk of re-infection is high.
Arbete med utveckling av ett kartsökverktyg för nationell naturolycksdatabas
We have made a suggestion for a map based search tool used with a database containinginformation on natural disasters. The database is being developed by NCO (SwedishCentre for Lessons Learned from Incidents & Accidents).We examined both Swedish and international examples of databases on naturaldisasters. The examples that we found were often hard to get the hang of, due to poorcompilation. The problem, that is typical of the international examples, is that the processof data collection is not standardized, as it is performed by different organizations andcompanies with diverse demands on and needs for the database. Therefore, to keep itsymmetrical, there ought to be only one department with the overall responsibility for anational database on natural disasters in Sweden.The natural disaster we based our study on was the flooding in Arvika in the year 2000.We inspected the availability of data about the flooding, and found it to be satisfying.Through contact with the municipality of Arvika, by mail and telephone, and a visit at theArvika municipality office, we acquired reports on the flooding and the joint rescueoperation that followed, and also GIS Layers showing the extension of the flooding..
Utvärdering av kalkstens egenskaper med laboratorie- och fältmetoder.
A pavement construction designed to cope with the different type of traffic loads; it is exposed to and at the same time it can resist the effect of the climate. A road structure consists of sub- and superstructure which is divided by a boundary known as terrace. During the construction of unbound Layers (base course and sub-base course) in the superstructure, it is always ensured that the material meet the requirements for bearing capacity and the degree of compaction. These parameters are controlled by various laboratory tests and control methods. To obtain increased knowledge of the material and improve the quality of the compaction in the field, it is necessary to perform laboratory tests in order to determine material properties.A base course material 0/ 32 mm limestone from Gotland (Hejdeby) was investigated in this study.
Kartering av markföroreningar inom Skutskärs Bruk samt utvärdering av spridningsrisker enligt Naturvårdsverkets MIFO fas 2
With the prospect of future construction on the Skutskär Pulp Mill property, Stora Enso Fine Paper has initiated an investigation of soil contaminants and a risk assessment of these contaminants. A soil and groundwater investigation has therefore been conducted on an open area of about 16 000 square meters, situated between the current wood room and digester house. To be able to integrate this study into an investigation for the whole industrial property, the study has been carried out as a phase 2 study according to the Swedish Environmental Protection Agency?s Methods of Inventories of Contaminated sites (MIFO).The site investigation has involved soil and groundwater sampling, together with the analysis of heavy metals and organic contaminants. The degree of hazard posed by the contaminants, the level of contamination, the potential for migration of the contaminants, as well as the degree to which protection of human health and the environment is required in the area, have been weighed together for an overall risk assessment of the area with regard to human health and the environment.The investigated area was built up by filling in the coastal waters.
Ytterväggar : En jämförelse och livscykelskostnadsanalys
This report discusses the constructionof different types of exterior wallconstructions and analyses wall Layers.Standard wall constructions from theSwedish building contractors NCC andSkanska and also from the materialproducer Isover have been chosen for theresearch. Life cycle cost analysis hasbeen made to conclude the mostprofitable wall type, seen from asustainable and economic perspective.The calculations have been made for aperiod of 50 years.The report shows that building with wellinsulated walls is a more profitablesolution both economically and whatconcerns sustainability even though thehigher investment. However, when wallssimilar insulation properties are beingcompared, the study proves that lowerinvestment cost is more profitable.The report introduces requiredconstruction techniques of walls inorder that the reader should understandwall constructions with different Layersand properties. The essay shows theimportance of properly constructed wallsto avoid air leakage and moisturedamage.The essay has been implemented byliterature studies, contacts with NCCand Skanska and by energy calculationsmade by hand and using the software VIPEnergy..