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402 Uppsatser om Descision Tree - Sida 6 av 27

The major food trees of the Angola black-andwhitecolobus (Colobus angolensis palliatus)in Diani Forest, Kenya

The Angola black-and-white colobus (Colobus angolensis palliatus) is a subspecies of Colobus angolensis inhabiting fragmented forests in coastal Kenya and Tanzania. C. angolensis is regarded as Least Concern in the red list of IUCN because its populations are abundant. However, the populations of C. a.

Höjdtillväxt, överlevnad och skador i praktiska etableringar av hybridaspbestånd i södra Norrland, anlagda 2004-2011

Hybrid aspen is a crossbreed between European and North American aspen. It is a fast growing tree species that has shown strong growth in the South of Sweden. The follow-ups that have been made on hybrid aspen stands, have mainly been done on plant material in the South of Sweden. In the North of Sweden, only occasional studies have been made, and the knowledge of Northern hybrid aspen stands is, thus, unsatisfactory.In the South of Norrland, land owners have planted hybrid aspen, but what kind of plants it is, and how well these stands have established, is not ascertained, since data has not been compiled on the subject.The objective of this study is to evaluate practical plantations of hybrid aspen in the South of Norrland regarding height growth, survival and damages. The ambition is to increase the knowledge about practical plantations regarding height growth, survival and damages, and from the conclusions thereof, give recommendations for future establishments of hybrid aspen in the area.For the study, eight hybrid aspen stands in the South of Norrland were localised.

Effekterna av urbanisering, barksprickedjup och solexponering på lavfloran i sydöstra Sverige

Studies have shown that air pollution, as well as bark fissure depth and sun exposure of a tree can have an effect on lichen growth as well as abundance of lichen species. The aim of this study was to find out the relative importance of these factors. 211 oaks in south eastern Sweden were surveyed for presence of 17 lichen species, as well as the total number of lichen species. Half of the trees were situated in urban areas and half in the countryside. For each tree the bark fissure depth was measured and the sun exposure of the trunk was estimated.

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.

Att täcka en obekant yta med Spanning Tree Covering, Topologisk Täckande Algoritm, Trilobite

Det har blivit mer och mer vanligt med ny, datoriserad teknik i hemmen. Fler människor har ett allt stressigare liv och inte längre samma tid att ta hand om det egna hemmet. Behovet av en hjälpande hand med hushållsarbete har blivit allt större. Tänk själv att komma hem från jobbet eller skolan och så har golvet blivit skinande rent utan att Ni knappt har behövt göra någonting! Det finns idag flera olika robotar på marknaden för detta ändamål. En av dessa är den autonoma dammsugaren, som är det vi inriktat vår uppsats på.

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.

Där jag aldrig varit

The sites I visit turned into routines a long time ago. Everywhere someone has decided what should be there and what will not fit. I retreat into my daydreams, away from everyday life. A longing for something different, something wonderful. I decided to go where I've never been, searching for something unknown.

Att täcka en obekant yta med Spanning Tree Covering, Topologisk Täckande Algoritm, Trilobite

Det har blivit mer och mer vanligt med ny, datoriserad teknik i hemmen. Fler människor har ett allt stressigare liv och inte längre samma tid att ta hand om det egna hemmet. Behovet av en hjälpande hand med hushållsarbete har blivit allt större. Tänk själv att komma hem från jobbet eller skolan och så har golvet blivit skinande rent utan att Ni knappt har behövt göra någonting! Det finns idag flera olika robotar på marknaden för detta ändamål. En av dessa är den autonoma dammsugaren, som är det vi inriktat vår uppsats på.

En jämförelse av sitkagranens (Picea sitchensis) och den vanliga granens (P. abies) produktion :

Sitka spruce (Picea sitchensis) is a tree species that have its natural distribution along the West Coast of North America, from Alaska in the north to northern California in the south. Sitka spruce is a typical coastal tree species that can reach heights up to 85 meters and occurs in single pure as well as in mixed stands. The main purposes of this study were to describe the Sitka spruce growing characteristics and the volume production in comparison to spruce (Picea abies). The possibility to predict future volume production by using prognosis tools designed to be used on spruce were also studied. The material that has been used in this study are permanent sitka trials established by the Faculty of Forestry fixed Sitka trials and also material gathered in this study. A literature study was also carried out in order to determine the Sitka spruce growing characteristics. Sitka spruce has a high adaptation and a high volume production on a broad scale of soil types. The tree species is a pioneer species that has a fast early growth and in combination with sharp needles it is less susceptible to animal browsing than spruce. The factor that is the single most limiting factor for where the Sitka spruce can be planted is frost. This factor can be limited by using plant material with a well-suited provenance. According to the literature, the Sitka spruce has an average total volume production that is between 20-40% higher than spruce.

Att bygga en stamdatabas för gotländsk tall

Today's Swedish large-scale forestry uses almost exclusively computer-aided bucking. It allows the harvester computer, using an optimisation price list (steering price list), to maximize the value of each tree. The optimisation price list can be adjusted so that the industry gets the raw material it demands from the forest. There are various simulation programs that can be used when constructing a optimisation price list. The simulation program merchandise a database of stem shapes using a given price list and mimics a harvester's work. To get the demanded raw material for the industry it is important to use a well-adjusted optimisation price list.

Shooting Target - Konstruktion : Product Development

The shooting sport is one of the most widespread sports in the world and it isbeing practice in most countries. Based on their own experiences, in competition -and hobby shooting, the client M4Solutions found a demand and need for ashooting target that is manufactured in Sweden.The purpose of the project has been to develop, with the help of Marcus Walldén,two shooting targets from idea to finished product. These two shooting targets,Plate Rack Target and Dueling Tree, would each be equipped with a mechanicalresetting system but will in the future have the ability to be provided with anelectronic resetting system.The project from the client was divided into two theses. One of these two, writtenby Marcus Walldén, focused on the tripod parts and the overall design work forboth Plate Rack Target and Dueling Tree. The thesis that is presented in thisreport have focused on resetting systems, the design of protective plates and otherperipherals for both shooting targets.This work has primarily been in CAD environment where design, constructionand development has been given free rein.

Skiktning och strukturell utveckling i unga naturlika skogsplanteringar: :

Multilayered woodland types are an important part of the urban forest. The knowledge how to establish and maintain such plantations are not as deep as other knowledge fields concerning forestry. Therefore this study has looked upon how to achieve multilayered structures in young nature-like woodland plantations. As a theoretical base for the study three different major knowledge culture have been studied that concerns the subject, ecology, forestry and landscape management/design. This three theoretical framework concludes that many natural processes strive in the opposite direction of multilayered structures in their youth.

Val av tidpunkt för markberedning vid naturlig föryngring under skärm av Pinus sylvestris i Svealand : Timing of scarification when using natural regeneration in seed tree stands of Pinus sylvestris in Central Sweden

This thesis is built on a field study that was carried out in two seed-tree stands near by Götbrunna in Uppland, Sweden. The aim was to examine if scarification carried out in spring time could generate a more dense seedling establishment when using natural generation, than scarification carried out in autumn. It was also investigated whether there were differences in mortality the first season between the two plot-types. Plots were established block-wise with 50 blocks (pairs) on each site. The spring scarification was made with a hoe during 22-23 of April.

Site preparation, planting position and planting stock effects on long-term survival, growth and stem form properties of Pinus contorta on southern Iceland

In order to evaluate different afforestation methods for exposed heath lands a field experiment was established in Mosfell on southern Iceland in 1989. The trial comprised six different site preparation methods (control, herbicide application, tree shelters, patch scarification, TTS trenching and mounding). In total 960 container seedlings (1+0) and 960 Nisula roll transplants (2+1) of lodgepole pine were planted. Various planting positions (furrow, hinge, no site preparation (control) and on top of mounds) were tested within the site preparation treatments. This study involves renewed measurements and analyses of the trial.After 19 years the overall survival was 51,7 %.

Lövsuccessioner i sluttningar längs nedre Umeälven :

Secondary deciduous forests, which have their origin in earlier pasture- and meadow-land in slopes along the lower reaches of the Ume river, are thought to contain high nature conservation values, in spite of a relatively low age. The aim of this study was to clarify how factors as historical use, exposition, disturbance dynamics and successional age influences the conservation values in these types of riparian forests and how this can be implicated in the practical work with conservation and management at Umeå municipality. Sample plots were placed in seven stands with a variation of their historical use, exposition, disturbance dynamics and age of succession. Conservation values as structure, tree-regeneration, abundance and composition of vascular plants, amount of dead wood and the abundance of signal-species were measured and registered. The species composition and especially the composition of tree species, differed between forests with different exposition and different historical use.

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