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1956 Uppsatser om Bark structure - Sida 2 av 131
Produktionsskillnader och virkesskador med olika typer av matarvalsar :
Earlier investigations showed that damages on timber from feeding rolls could be within the lower classes of damage according to VMRs classes. Knowledge about differences in productivity between kind types and aggressive types of feeding rolls is necessary because it should influence the question about damages on timber caused by different feeding rolls.
In this study the production and timber damage in a harvesting head were evaluated at three levels of pressure (8, 10 and 14 MPa) on the feeding rolls, and with three different types of rolls. One type, the rubber cushioned steel plate roller had 10 mm studs and rubber damping, one ?middle? type made of solid steel with 14 mm studs, and one aggressive type, also made of solid steel with 18 mm studs.
Epiphytic lichen flora in a boreal forest chronosequence
Epifytiska lavar utgör en viktig del av floran i den boreala zonen. Några miljövariabler är kända för att styra artrikedomen och artsammansättningen av epifytiska lavar på beståndsnivå, såsom träddiversitet, beståndsålder, fuktighet och trädens barkstruktur. Skogsbränder utgör den viktigaste störningen i boreala skogar men studier på brandeffekter på epifytiska lavar är mycket få. Detta arbete undersökte artrikedomen, diversiteten och artsammansättningen av epifytiska lavar på basala delar av björkar längs en gradient av 30 skogsbeklädda öar som skiljer sig i storlek och brandhistorik i den norra boreala zonen i Sverige. Målet med studien var att undersöka hur lavfloran påverkades av östorleken och miljövariablerna längs gradienten.
Biomass losses during short-term storage of bark and recovered wood
Storage of biomass is associated with problems like heat development, biomasslosses, and reduction of the fuel quality. Certain processes such as biological- andchemical degradation are responsible for these storage problems. This master?sthesis was carried out at Vattenfall Research and Development AB and is alignedtowards quantifying the biomass losses from short-term storage (1-2 months) ofbark and recovered wood. The biomass was stored in outdoor piles during differentseasons, campaign 1 (summer) and campaign 2 (autumn).
Vilken är den teoretiskt optimala toppdiametern på bokmassaved vid motormanuell avverkning?
The bioenergy market has been introduced relatively late in a perspective of the Swedish forestry. Nowadays branches and tops are used more frequently as bioenergy after harvesting. Therefore, it has developed a competitive situation between pulpwood and bioenergy. This situation has even established some questions. Two examples of these are:
? At what top diameter should the final piece of pulpwood be crosscut to get the best economically result?
? Should the top diameter, at the final piece of pulpwood, be crosscut at a thicker or smaller diameter than what is done today?
The purpose of this report is to answer these two questions when the harvesting is made motor manually in beech stands.
Rotpostvolym = stämplingslängd?
This work was conducted during spring and summer 2012 together with the company Uppsala Academy of Management as the principal. The two main objectives for the work are that:
? Make a comparison between the measured volume in the standing forest and the measured volume at the industry on Uppsala Academy of Managements actual stumpage sale volume to see how well it conforms.
? Examine if the buyers see any particular advantages or disadvantages of actual stumpage sale volume and what they think of Uppsala Academy of Managements actual stumpage sale volume and structure in general.
I chose to use actual stumpage sale volume from the tree years 2009, 2010 and 2011 in my work. I divided the actual stumpage sale volume following four categories which was pine, spruce, pine/spruce and seed trees. After that I picked out sixteen actual stumpage sale volumes from each category to be a part of the work.
Testing and optimization of Unicorn Fluid-Structure Interaction solver for simulating an industrial problem
In industry applications, such as power supply plants, the issue of interaction between fluid and structure is always presented. More precisely, the fluid flow affects the structure by applying force(s) on it and vice versa. As a result, the structure can move (vibrate) or deform. A good understanding of this problem can help to design the system in term of safety, stability and efficiency.This project aims to optimize and test the Unicorn FSI solver from the FEniCS project [1] to simulate the interaction of fluid and structure in an experiment, which was carried out at Vattenfall Research and Development. The target is to improve the Unicorn FSI solver to cope with a real industrial problem.
Utredning av barkhanteringen vid Billerud Karlsborg AB
Uppgiften bestod av att göra en undersökning av barkhanteringen vid Billerud Karlsborg AB med avseende på ekonomi och barkens torrhalt. Undersökningen omfattar allt från stock till förbränning och eventuell försäljning av barken. Tidigare så förbrukades all bark i barkpannan, där ånga produceras för torkning av pappret och elproduktion i ångturbinen. I dag har stora delar av pappersbruket byggts om och effektiviseras, vilket medfört att bruket producerar mer ånga än vad som behövs och vad turbinen klarar av att förbruka. Den bark som inte förbrukas av Billerud försöker man sälja och barken som blir över lagras i en stor barkstack.
Kapitalstruktur och Affärsrisk
During the past year it has been made possible to buy back a company?s outstanding stock. This is done in order to change the capital structure towards a situation with less equity. A change in capital structure means a change in the cost of capital for a company and by that a change in the value for the stockholder. This Master Thesis studies the relation between capital structure and business risk.
Swedish SME Financing - Evidence from the Game Industry
The objective of this thesis is to examine the capital structure of Swedish small and medium sized enterprises (SMEs). Accounting data from Swedish game developers, combined with the result from a survey, is used to examine their financial conditions and capital structure decisions. We find that non-debt tax shield, firm size, growth opportunities and age are, to various extents, the determinants of capital structure in the game industry, while effective tax rate and asset structure have marginal effects. Our study also implicates that most of the existing capital structure theories can explain SMEs leverage decisions to some extent; however, some adaptation is needed to fit these theories into the SME context. Additionally, we find the existence of a financial gap in the game industry which might need efforts from both demand side and supply side to eliminate..
Platt Hierarki : Metoder för omvandling av relationsdata till hierarkisk data
The relational database model was defined in the 1970?s and is the dominating database type today. The main difference between data from a relational database and a hierarchical data structure is that the relational database stores records in tables. The records have no particular order, but can include links in terms of relationships with other records. A hierarchical structure organizes data in the form of a tree structure and can for an example be found in organizational structures in which different levels involves different responsibilities. If the data stored in a relational database is to be presented in a hierarchically, a conversion of the data structure is required. The intention of this paper is to describe how such a conversion can be performed. To investigate the conversion methods, case studies has been conducted on the basis of a specific organization?s hierarchical structure.
The Incentives Behind Capital Structure Decision - A Survey of the Swedish Market -
The aim of this thesis is to investigate which the main determinants of capital structure in Swedish listed firms are and to identify which incentives lies behind managers choice of capital structure determinants. Further, the study investigates whether the Post Keynesian theory and theories which incorporate behavioral aspects can be used to explain the capital structure decisions or if the traditional Neoclassical theory give an better explanation. We have used a qualitative method to analyze the determinants of capital structure and the managers incentives behind capital structure decision. We conducted a survey which was sent to 83 Chief Financial Managers and financial executives in Swedish firms listed on Mid Cap or Large Cap. The questionnaire was on-line which enabled for the respondents to quickly and convenient respond.
Target Capital Structure and Adjustment Speed- a dynamic panel data analysis of Swedish firms
The purpose of this thesis is to test whether firms have target capital structure, and if so with what speed they adjust toward this target. Findings that support this purpose are also in line with the trade off theory. One of the key elements of this thesis is the method used, which successfully enables fulfilling the purpose. The panel data method captures the data characteristics of the cross sectional and time series dimension. By using this approach the dynamic effects of capital structure can be studied, thus if there actually is an adjustment towards a target the speed can be estimated.
Armeringsmatta och bark som markstabiliserande material på betesytor till mjölkkor - en utvärdering
Ett vanligt problem på mjölkgårdar är att trampskador uppkommer på betesytor som är kraftigt belastade av mjölkkor under betessäsongen. Den genomsnittliga besättningsstorleken i Sverige stiger och det leder till att problemet med trampskador ökar. Risken för trampskador tilltar vid stora mängder nederbörd. För att undvika trampskador på marken går det att dränera och ta bort matjorden och lägga dit ett markstabiliserande material. Bark som markstabiliserande material har i tidigare studier visat sig vara bra om barken är ordentligt packad.
Productivity of integrated harvesting of pulpwood and energy wood in first commercial thinnings
The aim of this study was to quantify the productivity and the costs of different harvesting systems (teams), containing harvesters equipped with accumulating harvester heads and forwarders, in first commercial thinnings were an integrated harvest of pulpwood and energy wood were performed. In the beginning the plan was to study and measure 20 sites before and after harvest. Due to storms during the summer of 2010, complete data could only be obtained from 8 of these 20 sites. Seven of these sites were privately owned and one was owned by UPM, all of the sites had been pre-commercially thinned. The mean stem density before harvest was 2578 stems per ha and the mean stem volume was 0.074 m3solid over bark.On average 1518 stems/ha was harvested.
Bark och armeringsmatta för att förebygga trampskador på betesytor hårt belastade av mjölkkor : en utvärdering
Ett vanligt problem på mjölkgårdar är att drivningsgator, grindhål, ytor kring vattentråg och andra högt belastade ytor blir söndertrampade under betessäsongen. Detta kan bidra till problem som sänkt djurhälsa, försämrad mjölkkvalité och dåligt fungerande kotrafik. De söndertrampade ytorna är även känsligare för jorderosion och näringsläckage. För att undvika denna typ av problem kan markstabiliserande material anläggas på dessa ytor. Detta examensarbete är en del av projektet Kamp mot tramp, ett projekt finansierat av Stiftelsen Lantbruksforskning.