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10397 Uppsatser om Wood-based beams - Sida 4 av 694

Förbättrat råvaruutnyttjande vid kvalitets-sortering av timmer : utvärdering av analysprogrammet Stockholmen för automatiserad timmersortering i dimensions- och kvalitetsklasser hos BARO WOOD AB

The aim of this thesis was to analyse BARO WOOD AB:s timber measuring and quality sorting and to evaluate the analyse program Stockholmen. The purpose was to get a better understanding for the quality sorting made at BARO WOOD AB today, analyse differences in center board quality from logs with a good quality and logs with a bad quality, suggest new sorting criterias developed from analyses made with Stockholmen and to evaluate the program Stockholmen. All analyses are based on data gathered in a test sawing made at BARO WOOD AB in June and July 2002. The test sawing was made on four different diameter classes and every diameter class consisted out of A or M-grade logs, with a better quality, and B-grade logs with a lesser quality. The logs where sorted out with BARO WOOD AB:s existing quality criterias.

"Underhållsfria fönster" : I vilken utsträckning är dagens "underhållsfria" fönster underhållsfria och hur ser man

AbstractThe aim of this examination paper is to get an overview on the ?no-maintenance? windowsthat exist on the Swedish market, like plastic and aluminium windows.By way of introduction the reader gets knowledge in the background and problemformulatethat this subject has. This introduction explains why it has become so popular to changeyour windows into plastic- and aluminium windows and there is an existing scepticismagainst PVC and aluminium as construction material for windows.The main part of this report is constructed by segments of interviews where bothproducers of windows and stakeholders gets to answer questions about their viewing onno-maintenance windows from a material and construction point of view and where theproduction is headed to in the future. This is followed by an evaluation of a questionnaireon how pleased the house owners that changed their old windows to no-maintenancewindows are, followed by an inspection of windows made up from wood and an aluminiumclothing, windows made from only aluminium and PVC-based windows. It ends with atheory part about the materials PVC and metal based upon facts included in literature.By reading this report you can draw the conclusion that no window can be entirely nonmaintenancebut that the materials PVC and aluminium still are good substitutes for woodto lessen the maintenance..

En jämförelse av skogsmarksprisets utveckling mellan Sverige, Danmark, Norge, Finland, Estland och Lettland

During the twenty-first century the price of forest land in Sweden has increased heavily. Buying forest land has become more common and the stakeholders have grown in number. The countries around Sweden have through the globalization become connected in the market of round wood and wood products. The price of forest land and round wood are also close connected. The goal with this report is to make a comparison of forest land prices between Sweden, Denmark, Norway, Finland, Estonia and Latvia and to see how the prices have developed in the period 2000-2011. The prime factor in the comparison, except the direct price difference between the countries, is the round wood prices. The round wood prices give information about the economic situation in the countries and play an important role in the return on the forest land. The prices of forest land shifts heavily between the countries.

Pelletskvalitet : Test av olika råvarumixer i pelletstillverkningen vid Rindi Västerdala AB:s bioenergikombinat i Vansbro

Fuel pellets are a refined bio fuel mostly consisting of residues from sawmills and wood industry. At Rindi Västerdala AB's combined bio energy plant in Vansbro fuel pellets are produced, while the waste heat from the process is used for district heating. The pellets are produced from sawdust, wood shavings and dry wood chips that is dried, milled and pressed into small cylindrical rods. The advantage of refining the wood material in this manner is that the energy value is greater per unit volume and unit weight, thereby the cost of transportation per energy unit is reduced. Also, less storage space is needed.Pellet manufacturing is a complex process since many parameters affects the final results.

Hur ofta bör småhus sotas? : En samhällsekonomisk analys av ändrade sotningsfrister

Sweden recently changed the national regulation of chimney sweeping. This study has two purposes. The first purpose is to evaluate the effect of this reform to see if the new regulation has led to an effect in terms of increased chimney fires in single-family houses and for the wood-burning and oil-burning stoves, respectively. The second purpose is an updating of a previous study (Mattsson 1994) of analysis of society´s benefits and costs of different alternative sweeping frequencies for wood-burning and oil-burning stoves. This study also has a secondary purpose to examine the extent to which the local sweeping rules vary with climate conditions.  Mattsson, based on his results, proposed that the sweeping requirements for oil-burning stoves should be reduced from twice a year to once every second year and for wood-burning stoves the sweeping should be reduced from four times to once each year.

Förstärkning av betongkonstruktioner med kolfiber med avseende på olika brottstyper

The purpose of this report is to simplify the process of designing carbon fiber strengthening for existing concrete constructions, specifically beams. The intention has been to establish a flow chart containing information on the necessary testing and calculations for the design, to as far degree it is possible satisfy the requirements stipulated by Swedish and by extension, European authorities.To do this the report will examine a parking garage situated underground by Akademiska Sjukhuset, Uppsala. The parking garage was built in the mid-seventies, and has in recent years been subjected to a greater load than designed for by the construction of a road on top of it. FEM-Design has been used to obtain the internalforces of the beams and thereby determine whether they are in need of strengthening or not and thereafter design the strengthening according to Täljsten (2006) with some corrections from Täljsten (2011) due to new regulations.The result of this report is that the flow chart used is viable to design carbon fiber strengthening, atleast with the conditions met in our reference project.The conclusion drawn after working with this report is that there is a need for a clear standard for carbon fiber strengthening , preferably a standard that can be used throughout Europe..

GROT-transport från norra till södra Sverige

The European Council agreed in 2008 on a climate and energy package to combat global warming. This package is valid for each EU member country and means that greenhouse gas emissions must fall by at least 20% and the EU's energy use to 20%, consisting of Renewable Energy in 2020. The Swedish Government has set stringent climate and energy with the intention to set an example for the rest of Europe. For example, renewable energy sources account for at least 50% of energy use and our climate emissions to fall by 40% by 2020. A combination of these goals and a steadily rising oil price has led to an increased demand for wood fuel in the form of such branches and tops.

Utvärdering av styvhetsegenskaper hos ett nyutvecklat träbjälklag

I samband med att intresset för att bygga högre trähus har ökat så krävs nya lösningar för att t.ex. kunna möta efterfrågan på stora öppna ytor och långa spännvidder. Träbjälklag med lång spännvidd har dock oftast svårigheter med att klara kraven på svikt och vibrationer. Ett nyutvecklat förslag på träbjälklag som förmodas klara dessa krav bättre än traditionella träbjälklag har varit utgångspunkten för detta examensarbete där syftet har varit att undersöka bjälklagets styvhet. Detta gjordes laborativt genom att bygga och testa en prototyp av det föreslagna bjälklaget och genom att en numerisk modell baserad på finita element metoden togs fram och användes för att studera hur olika parametrar påverkar bjälklagets styvhetsegenskaper.Bjälklagets design bygger på fackverksprincipen i primärriktningen och på balkverkan i sekundärriktningen.

Utveckling av gran, Douglasgran, bok och tall under skärm av hybridlärk :

?Development of Norway spruce, Douglas fir beech and Scots pine with a larch shelter wood? is a report written by Per-Olof Magnusson. The thesis is a compulsory part of forest engineer program at ?Skogsmästarskolan?, SLU, Skinnskatteberg, Sweden. The purpose of this report is to describe and evaluate an experiment with hybrid larch (Larix x eurolepis) as shelter wood, and different tree species growth and survival depending on the density of the shelter wood. The experiment is conducted by southern Swedish forest research centre, faculty of forestry, SLU in Alnarp. The hybrid larch ought to be an interesting alternative to birch (Betula sp.) as shelterwood on suitable sites in southern Sweden.

Energy efficient storage of biomass at Vattenfall heat and power plants

Storage of biomass is often associated with problems such as heat development, dry matter losses and reduction of fuel quality. The rise in temperature can potentially cause a risk of self-ignition in the fuel storage. Moreover, emissions from storage piles can cause health problems in the surrounding. The dry matter losses and reduction of fuel quality can have economical effects. The aim of this thesis project is to develop guidelines on how to store large amount of biomass at Vattenfalls heat and power plants in an optimal way.

Skillnader i mulmvolymer mellan fem trädslag i Östergötlands eklandskap

Old hollow trees of oak contain a large amount of wood mould. Unfortunately, these trees have in the last century been greatly reduced in numbers. It has resulted in that species that depend on these habitats, saproxylic species, have become at risk to decrease in numbers or die out regionally. Previous studies have shown that the volume of wood mould is an important factor for occurrence and population size of saproxylic organisms. The aim of the present study was to examine how the volume of wood mould varies among ash (Fraxinus excelsior), lime (Tilia sp.), maple (Acer platanoides), aspen (Populus tremula) and oak (Quercus robur).

Buddhismens krigare : Om buddhism, politik och våld

This graduation paper is based on my interest for wood and its different tonal quality?s.After some time of thinking I decided to write my paper on the tonal difference between two of the most common woods in guitars, East Indian Rosewood and European Maple. I had built two identical guitars before my graduation paper in which the difference was the wood the back and sides were made of. One was being made of East Indian Rosewood and the other being made of European Maple.I chose to speak with a number of people with different angle of approach to the two kinds of wood and its tonal difference and quality?s.

Identifiering av lek- och övervintringsområden för lax (Salmo salar) och öring (Salmo trutta) i Klarälven

Old hollow trees of oak contain a large amount of wood mould. Unfortunately, these trees have in the last century been greatly reduced in numbers. It has resulted in that species that depend on these habitats, saproxylic species, have become at risk to decrease in numbers or die out regionally. Previous studies have shown that the volume of wood mould is an important factor for occurrence and population size of saproxylic organisms. The aim of the present study was to examine how the volume of wood mould varies among ash (Fraxinus excelsior), lime (Tilia sp.), maple (Acer platanoides), aspen (Populus tremula) and oak (Quercus robur).

Hållbara uppvärmningsalternativ för Grinda Wärdshus : En studie om uppvärmning med pellets och flis

This report is a bachelor's thesis of two students from the Energy and Environment degree at KTH Stockholm. Grinda is an island situated Stockholm archipelago. Skärgårdsstiftelsen is landowners and manages the area. Grinda Wärdshus, a guest house located in the island, currently uses an oil-fired boiler as a heating system. The aim of this thesis is to investigate whether wood chips or pellets is, from a sustainability standpoint, a suitable heating method for the guest house.

Fuktkvotens inverkan på oljeupptag och pigmentinträngning i tall (Pinus sylvestris L.) och gran (Picea abies L. Karst) vid impregnering med Linotechmetoden :

Wood has always been an important material for people, and it is used for many applications. As for example, fuel for cooking and heating houses, construction materials and for constructing means of transport. Since wood also is a material that with time biologically degrades due to activity by micro organisms and wood fungi it is important to find ways to protect and further lengthen the life span of the material when in service. One method is to decrease the amount of water in the material by impregnation with an hydrophobic oil. The Linotech method which uses only pure linseed oil is one such possible method. The aim of this study was to investigate the possibility to at the same time impregnate and stain/colour wood samples of pine and spruce by using the Linotech method.

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