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410 Uppsatser om Timber damages - Sida 20 av 28

Ståndortsanpassning och produktionspotential för björk i Gävleborgs län

Large amounts of birch-timber are imported to Sweden, from particularly the Baltic States, since the domestic production can?t support the pulp industry. The goal of this study was to show the potential of birch and the area?s most suitable for birch production. The study was limited to Gävleborg County. Using site characteristics, site index (SI) for birch was estimated on all National Forest Inventory plots in Gävleborg County.

Antinutritionella substanser iåkerböna, ärter och blålupin vidutfodring till mjölkkor

There is a shortage of locally produced high quality protein concentrates in Europe andSweden. Local production would decrease the dependency on imported soybean and meet thedemand for organically grown feedstuff from ecological dairy farmers. Field bean (Viciafaba), peas (Pisum sativum) and sweet lupin (Lupinus angustifolius) are good alternatives tosoybean, but contain anti-nutritional substances (ANS) that could reduce their use as proteinconcentrates in dairy cow diets. The aim of this literature study was to review which ANSfield bean, peas and sweet lupin contain and whether they affect dairy cows negatively.Trypsin inhibitors and Chymotrypsin inhibitors (TI) were present in all three crops. TI couldbecome inactivated and degraded in the rumen, but due to the high passage speed of thedigesta, most TI left the rumen in an active state.

Utrustning för automatmontering av ackumulator

This report deals with an exam report written by Olle Hjalmarsson and Thomas Likar, students at Högskolan i Halmstad. The project was carried out for Haldex Traction AB in Landskrona whose business consist of manufacturing automatic all wheel drive systems (AWD-system). These systems consist of a plate clutch which activates all four wheels of a 4-wheel driven vehicle. An important component in these clutches is the accumulator which basically consists of a piston under the load of a spring which creates an oil pressure with the help of an electric motor used for actuating the clutch.At Haldex difficulties has been experienced regarding the assembly of the accumulator parts due to the small tolerances between the piston and the hole of the accumulator in the cast aluminium housing. Attempts have been made to assemble the parts in existing robot cells.

Användande av diffusionsspärr vid tilläggsisolering av äldre byggnader med trästomme

In the current situation a big part ofthe settlements that exist in Sweden isin need of renovation and energyefficiency in order to survive.Therefore, also many of the older houseswith a wooden structure are in a need ofenergy efficiency, which can be done ina variety of ways, including addinginsulation.This project deals with whether the useof a diffusion barrier or a vaporbarrier affects a wall structure byadding insulation to an older house witha timber frame. The insulation materialswhich are concidered in thisinvestigation are mineral wool and woodfiber insulation. Efforts are focused onthe effects of moisture on theseinsulation materials.To demonstrate the differences thatarise the moisture measurement programWUFI have been used to simulate avariety of wall designs. These designsare developed in consultation with theconstruction carers who are active inthe industry.Using WUFI graphs illustrating themoisture levels of the wall structureswere obtained and from these conclusionsvould be drawn. The work demonstratesthe differences that arise when using adiffusion barrier or vapor barrier inwall construction.

Short-term responses of the field layer vegetation in a south Swedish deciduous forest after establishment of wild boars (Sus scrofa)

Inside the south Swedish national park Dalby Söderskog, wild boars (Sus scrofa L.) have been visiting since 2010. The presence of wild boars has earlier been proven to impact both soil and vegetation characteristics, both positively and negatively. Still, there is a lack of knowledge regarding the rooting effect on the vegetation in deciduous forest within the native range. In this study, I have compared the field vegetation collected before and after the invasion of wild boars in 74 permanent experimental plots. More specifically, the study aimed to qualify the effect of wild boar rooting on cover ratio, species richness and species composition in a temperate deciduous forest.

Husväggar av massivträ: En kostnadsjämförelse

Trä är och har sedan länge varit en av Sveriges mest exporterade råvaror. Branschen sysselsätter idag omkring 100 000 människor i landet. I samband med de senaste årens miljödiskussioner bör husens uppbyggnad diskuteras. Syftet med detta examensarbete är att främja husbyggnation i massivträ som de senaste åren fått mer publicitet inte bara på den svenska marknaden men också i centraleuropeiska länder.Frågorna i detta arbete handlar om att identifiera de vanligast förekommande ytterväggskonstruktionerna och jämföra deras materialkostnader samt kostnader för arbete vid montering. För att ha kunnat göra en rättvis jämförelse har BBR?s energikrav varit den gemensamma nämnaren för ytterväggskonstruktionerna.Frågorna har besvarats genom intervjuer med tillverkare av prefabricerade massivträväggar, träregelväggar och betongväggar varpå energiberäkningar utförts i samband med framtagning av olika väggkonstruktioner för att få fram tre lika energieffektiva väggar.

Passivhus, detaljutformning och dess köldbryggor

Along with rising energy prices and increasing awareness of environmental issues, the criteria for buildings energy performance have been sharpened through the years. Today, ?passive house? and ?low energy house? are commonly used phrases in the construction industry and is expected to become increasingly common in the future.For houses with well-insulated building envelope the importance of well constructed details increases when minimizing the heat losses. Examples of these details are floor-wall junction and window openings in the wall. In such connections thermal bridges occur, which means that heat more easily is transported out of the building, compared to the rest of the building envelope.This report deals with detail solutions around windows and a comparison between a traditional slab and a foundation from Koljern consisting of foam glass.

Skogsentreprenad idag och i framtiden : en kvalitativ studie av skogsmaskinentreprenörersverksamhet och framtidsvisioner

The Department of Forest Products and Management, Swedish University of Agricultural Sciences has received means from Vinnova for a preliminary study of the organisation of logging work of today and how a better logging organisation should be brought about. This thesis reports results from qualitative interviews with nine forest machine contractors regarding the situation of their companies. The interviews have been analysed with respect to the genesis of the companies, which tasks they perform or that they could consider perform-ing, business relationships of the companies, relationships between the different partners of the companies, and the state of competition experienced by the contractors. The companies have developed either from the contractor previously being machine operator employee or from that the contractor in making has owned a machine and needed work. Their primary business is mechanised logging.

Virkesgripen, ett geometriskt verktyg :

The aim of this study was to investigate and describe conceptions that been used when people talks about grapples and to put together parameters that the customers sees as important when they chose a grapple from Hultdins. Every year Hultdins manufacturer and sells about 3500 grapples around the world. With so many users its difficult to oblige everyone. To get an apprehension of what kind of grapple the operators wanted a formula with 18 questions was made. For the interviews 20 forestmachineoperators were choicest who had experience from Hultdins grapples, a lot of them also had experience from other grappleproducers and constructions. The study showed that it is the durability the users give priority to.

Spawning site selection of brown trout in habitat restored streams

During the timber floating era, most of Sweden?s watercourses were altered. This decreased the amount of available spawning habitats for salmonids, and hence had a negative effect on the riverine brown trout (Salmo trutta) populations. Reconstruction of spawning grounds is today a common measure in restoration of altered streams in Sweden. However, very little evaluation of the effectiveness of these reconstructed spawning grounds exists.

Mätning av stamdiameter med markstående scanner :

Booth for operational planning of harvesting and for long term planning, data is today collected manually. Intensive objective field inventories are usually too expensive. To enhance optimisation of timber flow from forest to industry Moore efficient methods for measuring tree stems of standing trees are needed. The performance of terrestrial laser scanners have improved and these could possibly be used within forestry in the future. The objective of this study was to validate how a terrestrial laser scanner could be used to measure stem diameter, and to test how the errors depend on distance from the scanner and tree species. Two plots (one pine and one spruce) were used for this study.

Äganderätten eller allemansrätten : En studie av hur små och medelstora markägare i mellersta Sverige skyddas av rättssystemet vid markpåverkan orsakad av tredja man

The aim of this master?s thesis in administrative law has been to study the property owners' legal rights when a third party impacts on the property. The essay is based on several case studies of landowners in central Sweden which has the purpose of forming a background to the legal studies of this field. The framework for current studies builds therefore on landowners' experiences of impairment and damages on their property and has been added to highlight a current problem that exists in central Sweden. The purpose of the study is therefore to see whether a protection in law is imposed on landowners with such problems as the land ownership study shows.

Överlevnad och tillväxt för nyplantersade barrots- och täckrotsplantor : en studie av 42 bestånd i södra Sverige

The choice between bare-rooted and containerized seedlings in southern Sweden affects the investment costs as well as growth and survival. It is important to take these differences into account when choosing seedling type for reforestation. The most important differences between the two seedling-types is that bare-rooted seedlings has open root systems whereas the roots of containerized seedlings are grown in a container which may contain water and nutrients that are available for the seedling during the first period after planting. Moreover, bare-rooted seedlings are often older which results in thicker stembase and better resistance to attacks of pine-weevil (Hylobius abietis). In order to study differences in survival and growth between bare-rooted and containerized seedlings a survey study of newly planted clearcuts in south-western Sweden was made. In the study tree seedling types was included, one bare-rooted and two containerized with different ages. The population of pine weevils was probably low during the studied period which resulted in lower pine-weevil damage than normally found in this area.

Thuja plicata - etableringsförsök av jättetuja med fyra olika provenienser

Future climate changes may lead to an interest of alternative and foreign forest tree species in order to spread the risks in forestry. Douglas fir, Sitka spruce, Freemont cottonwood and hybrid aspen are examples of popular foreign tree species that along with western red cedar could have a future in the Swedish forests.Södra Skogsägarna and SLU have collaboration in establishment of foreign species in Swedish forests.The purpose of this study was to analyze and present the establishment of western red cedar, and to survey and illustrate injuries of freeze drying and other damages like deer browsing, vegetation and insect attacks. The study included four different provenances, and spruce as a reference, planted in two locations ? Asa and Släne.Western red cedar is despite its name a conifer of the cupressaceae family with defined secondary characteristic and gets along well with an overstory. Western red cedar grows often in mixed stands with similar conifers and its natural habitat is within and in the area near to British Columbia.The study included two series of field inventories, one made in the summer and one in the autumn 2013, three growing seasons after plantation.

Hög fyllnadsgrad i timmerlagret : en fallstudie av Holmen Timbers sågverk i Braviken

Holmen Timber har byggt ett nytt sågverk i Braviken, utanför Norrköping. Målsättningen är att såga 1 100 000 m3fub per år, i sågad form 550 000 m3SV (SV=sågad vara), till år 2013. För att utvärdera olika timmerplanslösningar har simuleringsverktyget Simsaw utvecklats. Med hjälp av programmet kan timmerflödet av ankommande timmer fram till sågen simuleras och dess effekter utvärderas.Syftet med studien är att analysera utfallet av olika timmerplanskonstruktioner, där vältors antal och längder förändras för att hitta en lösning som skapar en hög fyllnadsgrad av timmerlagret. Vilket i sin tur kan skapa ett bra underlag för sågen att såga långa sågserier med få ompostningar som positiv följd.

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