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2171 Uppsatser om Springback and density of the compressed wood. In addition - Sida 8 av 145
Mindre studie av en ny gallringsmetod i stamtät förstagallring av gran i södra Svergie
The main purpose of this study is to investigate how to reduce the high, and every decade raising, pre-clearance cost. The pre-clearance is today carried out with a brush saw and paid per labour hour. All small trees not suitable for pulpwood are removed to simplify the later work of the harvester.
The study compares the economic results from thinning of four parcels each treated differently regarding harsh or light pre-clearance and extraction of only pulpwood, or both pulpwood and fuel wood.
In this type of spruce stand the study indicates that a lighter pre-clearance, followed up with both pulpwood and a fuel wood extraction, has a much better economy than the traditional method of hard pre-clearance and only pulpwood extraction..
Omfattningen av icke avverkade områdeni samband med slutavverkning :
This final thesis is performed on commission of Torsby forestry administration, Stora Enso Skog. Stora Enso Skog is one of the major forestry companies of Sweden. The main business area is located in and around the region of Bergslagen.
During the last decade the practice of forest management has rapidly changed due to a new forest legislation. The new law has resulted in that the production goal is equal to the environmental goal within forestry.
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.
Blästring av trä : Ett materialbibliotek av blästrade och ytbehandladeträytor
In my thesis I have sand blasted different type of woods - ring-porous and diffuseporous deciduous tree species and conifers - to show different results depending on the species, the direction of the grain and the effects of surface treatment of a blasted surface.The results of my tests were sometimes unexpected, such as that the sand from blasting almost completely disappeared, that all wood surfaces after blasting exhibited a much lighter or paler surface than before and that the diffuse-porous tree species showed differences in hardness between the beginning and end of annual rings.By creating a library of different kinds of wood and sandblasted surface treatment, I have created a reference bank that I will be able to use me in the manufacturing of interiors, furniture and other objects..
Kv. Tvättstugan, ett flerbostadshus med massiv trästomme : Ett examensarbete om akustik- och brandkrav samt en jämförelse av energi- och fuktaspekter
Title: Kvarteret Tvättstugan, an apartment building with massive wood construction. A thesis about acoustic and fire requirements and a comparison of energy and moisture aspects. Earlier restrictions in the Swedish legislation have resulted that only a small percentage of the apartment buildings that have been built are designed with a massive wood construction. It has been allowed to build unrestricted with wood since 1994 as long as the function of requirements are fulfilled. This change in the rules together with the great environmental benefits of wood has led to that more companies choose to build apartment buildings with wood. One of these companies is Folkhem Production AB.
Sällskapet örtagårdens vänners trädgård i Vadstena : aktuellt växtinnehåll i historisk belysning och med sikt framåt.
Dead wood is important for many species. The amount of coarse dead wood (diameter >10 cm) is much lower in managed forest than in unmanaged forests. Stumps constitute the largest proportion of the volume of coarse dead wood in managed forests. Since stump harvest for biofuel may increase, the amount of dead wood will decrease even more, which may threaten biodiversity. The first aim of this study was to compare the amounts of fine woody debris (FWD, .
Wild boar paradise : What makes the Swedish wild boar reproduce more or less successfully?
Due to the growing wild boar (Sus scrofa L.) population in Sweden there has been an increase in wild boar related traffic accidents, damage on cropland, and conflicts regarding the management of the wild boar. Knowing what makes the wild boar reproduce and survive more or less successfully in different geographic areas is an important part of managing the population. According to previous studies the wild boars rate of increase varies from county
to county. The aim of this study was to test, on the county scale level, if landscape composition and diversity as well as people and hunter densities might be the reason for this
variation. The first hypothesis was that a big proportion of forests and cropland would increase the rate of increase.
Tidsberoende kvantkemiska beräkningar av optisk absorption hos polymerer och molekyler med litet bandgap
The vertical electronic excitation energies for the narrow-bandgap polymers LBPF, EP37 and EP62 have been calculated using Density Functional Theory (DFT). Also the vertical excitation energies for the acceptor unit of LBPF have been calculated using the Hartree-Fock (HF), DFT and Coupled Cluster (CC) methods. The calculations cover the visible and infrared wave length region and two strong transitions are obtained, one corresponding to the pi to pi* transition and one corresponding to the pi to Acceptor transition. The excitation energies obtained from DFT are below the corresponding experimental results and attempts have therefore been made to perform bench-marking calculations using a hierarchy of CC methods..
Introduktionen av addition och subtraktion i årskurs ett. : Med fokus på läroböcker och lärares förhållningssätt till dessa.
Syftet med detta examensarbete är att studera hur addition och subtraktion introduceras i årskurs ett. Fokuset kommer att ligga på läroböckerna. I studien kommer det att undersökas hur läroböcker väljer att introducera addition och subtraktion samt hur lärare väljer att förhålla sig till dessa läroböcker och hur de använder sig av dem i undervisningen av addition och subtraktion. De valda metoderna för att undersöka detta syfte är samtalsintervjuundersökningar och kvalitativ textanalys. Fyra stycken lärare har blivit intervjuade och utifrån dem har tre läroböcker valts ut till analys.
The effect of new raw materials on pellet prices
As demand for renewable energy is increasing rapidly, the market for biomass pellets
is expected to continue to grow in the near future. Most of the new raw materials that
are discussed for pellet production have one thing in common; the production costs
will increase compared to using traditional raw materials such as sawdust and planer
shavings. The aim of this thesis is to investigate to what degree increased use of new
raw materials for pellet production will affect the general pellet prices in Sweden and
to survey what plans Swedish pellet producers have concerning new raw materials.
To investigate the raw material situation of the Swedish pellet producers an industry
survey was performed. Literature studies were also made on previous research in the
subject field. Calculations of the production costs for pellets were done for the raw
materials sawdust, wet sawmill chips and energy wood respectively.
New raw materials are already used by the large-scale pellet producers in Sweden.
Är frågan färdigformulerad? : En referenskritisk undersökning av 118100 Svar På Allt och Fråga Bibliotekets e-posttjänst
This two years master?s thesis in Library and Information Sciences aims to investigate and put the services of 118100 Svar På Allt (SPA, an SMS mobile question and answer service) and Fråga biblioteket (FB, a library operated e-mail reference service) into the context of the reference encounter. Questions sent to SPA and their subsequent answers are analysed, and part of these questions are forwarded to FB for comparative studies. Both of the formats are compared to the reference encounter as a whole. The framing of the question originates in the assumption that there may be a need for further negotiation of the questions submitted to the aforementioned formats.
Ekonomiska konsekvenser av förändrad röttolerans vid Bravikens Pappersbruk :
The competition for Norway spruce pulp wood in Central Sweden increases, forcing the supply-structure of Holmen to face two important challenges. Firstly, it is of the outmost strategically importance to secure the long-term supply of Norway spruce pulp wood to the industries. Secondly, Holmen desires to increase the obtainable volume of Norway spruce pulp wood. This would enable the company to choose volumes in the lower price-segments and thereby decrease the dependency of costly marginal volumes.
As this work shows, one part in managing these challenges could be to lower the quality standards concerning root rot (Heterobasidium annosum).
Facts presented in the work shows that:
1. Technically, the TMP-industry of Braviken can handle a much more rotted pulp wood than that used today, although the cost of refinement increases.
Effekt av biotopvård på öringpopulationen i två vattendrag
I have done a follow up study of the restoration of two rivers, Röälven and Grundan, in order to evaluate the effects of the restoration on the endemic population of trout. Both rivers have been used for timber floating during many years throughout the 20th century, and because of this, had all obstacles such as rocks and wood parts removed. In 2004-2005 both rivers were restored, and rocks and wood were put back into the rivers. Spawning grounds were created and boulder dams were constructed to promote the streaming water. The result showed that the trout population of both rivers increased after the restoration, but also that the trout population of Röälven increased more than that of Grundan.
Om behovet av ett avrinningsområdesanpassat skogsbruk
The Swedish forest have about 100 000 km of watercourses and it?s an important structure in Swedish landscapes and catchments. In some of the watercourses lives spieces like the freshwater pearl mussel (Margaritifera margaritifera) and brown trout (Salmo trutta) which both are sensitive for inteference from the forestry. The new EU water framework directive has a goal that all surface water will have high or good ecological- and good chemical status at latest by the 22nd December of 2015.
The study has been made in the catchment of Håltjärnsbäcken and it is from a national perspective one of the most valuable streams in Sweden and which also have been included in a LIFE-project. The catchment is situated within the Eco-park of Malingsbo-Kloten and managed by Sveaskog AB.
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.