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2171 Uppsatser om Springback and density of the compressed wood. In addition - Sida 10 av 145
Automatisering av grundläggande additionskombinationer : En kvantitativ studie av ett interventionsprogram i årskurs 7
Att ha automatiserat grundläggande additionskombinationer i talområdet 0-20 kan underlätta elevers vidare matematikutveckling. I detta utvecklingsarbete undersöktes om ett interventionsprogram bestående av strategidiskussioner, kombinationsträning samt minuttest i årskurs 7 var effektivare än enbart minuttest. Vidare analyserades om ökad säkerhet med additionskombinationerna 0-20 ledde till en generalisering till addition inom talområdet 20-99 samt till subtraktionskombinationer inom talområdet 0-20.En mixed ANOVA med enkla kontraster genomfördes och resultatet visade att interventionsgruppen utvecklades något bättre än jämförelsegruppen under interventionsperioden fram till eftertestet i addition 0-20 men det fanns ingen statistiskt signifikant skillnad mellan grupperna för hela testperioden. Generalisering skedde till addition 20-99 för båda grupperna men interventionsgruppen utvecklades bättre än jämförelsegruppen i subtraktion 0-20. En slutsats är att det är en fördel för eleverna att bli säkrare på de grundläggande additionskombinationerna då de även blir säkrare på addition inom talområdet 20-99 och med träning även säkrare på subtraktion inom talområdet 0-20.
Planteringsförbandets inverkan på bestånd av contortatall (Pinus contorta var. latifolia) med avseende på volymtillväxt och virkesegenskaper
At the beginning of the 1970´s forestry feared an imbalance in the future wood supply. Because of this anticipated "timber slump" forest companies undertook a variety of measures to counter this. One of these measures was the introduction of exotic tree species. The choice finally ended up with lodgepole pines which were considered a fast growing tree species compared to our native tree species. Theambition for the new lodgepole pine stands were to run these with rotation periods of between 40-60 years, thus smoothing out the ?timber slump? that was anticipated.
Virkets formförändring och dess betydelse vid postning :
The purpose of this thesis was to create a saw pattern program for the sawmill industry. I have chosen to focus on the module that describes the shrinking on the wood. There are several theories about how the wood deforms by shrinking. Several hypotheses were simulated in the program and after testing them I decided to use only one of them (hypothesis C).
The program is written in Visual Basic .NET and I choused that program language because it
is easy to do changes in the layout. Another great advantage in Visual .Net is that you can mix different languages in the same program.
Vedrötor i stadsträd : biologi, detektionsmetoder och förebyggande åtgärder
Urban trees have very little in common with trees on natural sites, such as forests or pastures. Trees in urban environments are often planted in packed soil and in small volumes. This can lead to decreased availability of water and oxygen, as well as deteriorated ability for the soil to store nutritional elements. Also above ground the tree usually have limited space in cities. Regulations on free height over roads and cycle tracks demands high stems at an early stage of their development.
Tonala skillnader i Ostindisk jakaranda och Europeisk lönn
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.
Balis trädgårdar
The urbanization of the world is increasing. How it affects bird populations have been well studied during the last decade, and comparisons between urban and non-urban habitats have been carried out. A common method for measuring habitat quality is to calculate the population density. This method is easy to use, but have been criticized during the last couple of years. In this study, data of population densities was compared with data on reproduction success.
Skogsbränsledrivare i klen förstagallring med contorta
The aim for the study was to examine a harwarder´s (combined harvester-forwarder) productivity when harvesting forest fuel in first thinning stands that contains Lodgepole pine and calculate the economy of the harvesting work and estimate the quality of the thinning . The field study area where located near Arvån, about 15 kilometres south ?east from the city of Lycksele. The field studies were taken place in three different stands. All tree stands had the same tree age, but the tree species combination and the density varied.
En studie av begreppet uppfyllelseort i artikel 5 (1) b i Bryssel I-förordningen
The courts international juristiction within the European union is regulated by the Brussels I Regulation. Article 2.1 of the Brussels I Regulation contains the fundamental provision. According to this Article the plaintiff shall submit an action where the defandent is domiciled. The Regulation provides exemptions to the this provision in Article 2.1.The court of the international case can also be determined according to Article 5 (1) of the Brussels I Regulation. This Article contains an alternative to the general provision within Article 2.1.
Metoder för addition och subtraktion : En litteraturstudie av matematikböcker för tidiga skolår
Syftet med denna studie har varit att undersöka och jämföra vilka metoder inom addition och subtraktion som förekommer i två matematiklärobokserier. Vi har sökt svar på frågorna: vilka metoder för addition och subtraktion som läroböckerna ger, hur dessa behandlas och bygger vidare på varandra samt hur böckerna förhåller sig till gällande läro- och kursplaner.Den metod vi har använt oss av är en innehållslig idéanalys, eftersom vi tittat på dels vad, men också hur det tas upp. Materialet vi använt denna metod på är två matematiklärobokserier, som är reviderade till gällande läroplan, Lgr11. Som verktyg för att genomföra denna studie har vi utarbetat ett analysschema som har fokuserat på vilka metoder böckerna tar upp samt tre metaforer som beskriver hur det tas upp.Resultatet av denna studie har visat att det finns stora skillnader på hur böckerna arbetar med addition och subtraktion. Den ena boken tar upp metoderna flera gånger, börjar grundande och bygger vidare för att fördjupa och utveckla kunskaper.
Hur påverkar bävern skogens värden?
The activities of beavers in forested landscapes affect both ecological and economical values. The creation of the dynamic wetland mosaic associated to beaver activities can even improve the quality of water and have been documented as an important landscape engineer affecting the environment for many species. The local office of Sveaskog in Skinnskatteberg is responsible for the management of large areas of the forests in the County of Västmanland. In this area one of several company?s goals are to create ten new wetlands in their own forests as a part of cooperation with the Swedish bird society and Swedish wetland association.
The shift in forest and tree limits in Troms County - with a main focus on temperature and herbivores
To better understand how various factors affect the establishment of forest and trees around the tree line-ecotone, this study was conducted in Troms County, Norway. The altitude of different forest and tree limits together with the surrounding vegetation type were collected during August 2011. Comparisons of the collected data were made with previously collected data from the same sites conducted 1914 and 1915. On average the forest limit has expanded with 26 meters in altitude, however, an expansion is not statistically significant for the whole area. The tree limit has significantly expanded in altitude.
Bättre åtkomst till avverkningstrakter med anpassat marktryck från avverkningsmaskinerna
The global climate-change means increasing mean-temperature and higher precipitation in Sweden, which leads to shorter periods of frozen ground in the forest. At the same time the harvesting machines are getting bigger and more powerful. The forest industry aim at an even wood flow, and the ground damage has to be as low as possible. The two biggest causes for ground-damage is the bearing capacity of the forest ground and the ground-pressure of the harvesting machines. The aim of this study was to find out some rules for the machine choice considering ground pressure, when harvesting on ground with low bearing capacity.A field study, using a Valmet 890.3 forwarder, was carried out where different ground pressures and their effect on the ground were tested on two different types of ground.Additionally, an inventory of damaged harvesting grounds was made.
Environmental variables determining the occurrence of the red-listed Carbonicola anthracophila and C. myrmecina in boreal forests
The global biodiversity loss is mainly due to human activities such as an intensification of forestry. Boreal forest ecosystems in Fennoscandia are characterized by disturbances such as forest fires, storms and floods. However, industrial forestry practices suppress forest fires and change the landscape, leading to a loss of habitats and associated species. Particularly lichen species with slow adaptation abilities and a strong substrate specificity face an extinction debt in boreal forests since their substrates are long-lived but no longer created. In this study the species-substrate relationship of two red-listed forest-fire dependent lichen species Carbon-icola anthracophila and C.
Energieffektivisering genom förvärmning av flis till kokare med sekundärvärme
The Swedish pulp and paper industry meets higher demand for energy efficiencyi mprovements with increasing energy prices and changes in the Swedish renewable energy certificate system. One action of energy efficiency improvement is by using secondary heat, that otherwise would have been treated as waste heat, for use in a system with lower temperature demands. The aim of this Master´s thesis is to identify possible secondary heat sources in a typical Swedish pulp and paper mill and to investigate what economic benefits the secondary heat will provide when being used for pre heating of wood chips to a kraft digester.The Master´s thesis focuses on three secondary heat sources; dry warm air, warm water and moisture saturated warm air located inside the pulp or paper mill. Two types of kraft digesters are simulated within this study, a typical Scandinavian digester and a modern twin vessel steam phase digester.Due to quality aspects and low temperature level drying is the drying technology with dry warm air rejected. Using warm water in direct contact with wood chips increases the quantity of water to the evaporation plant and thus reduced pulp or paper production and is therefore also rejected.
Influence of prescribed burning and/or mechanical site preparation on stand stem density and growth of Scots pine stands above the Arctic Circle : results 9-19 years after stand establishment
Prescribed burning was commonly used for site preparation in Sweden to establish new forests until the 1960?s, when mechanical scarification was introduced. During recent decades the interest in prescribed burnings has increased again, mainly due to certifications of forestry stating that 5% of the regeneration areas should be burned on dry and mesic soils.
The objective of the study was to evaluate actual influence of prescribed burning compared to other site preparation on stand stem density, growth parameters and tree damages for Scots pine (Pinus sylvestris L.) after direct seeding and planting. The study also attempts to simulate growth until first thinning.