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1010 Uppsatser om Random Forest - Sida 11 av 68

Honeycomb & path generation : En struktur för en ständigt växande karta ochgenerell generation av slumpmässiga vägar

Ett spels karta är begränsande i det att när man valt en viss storlek kan man inte gå utanför den ramen utan att göra relativt resurskrävande operationer. Denna undersökning genomfördes för att se om en trädstruktur kan användas som lösning att hantera en honeycomb-struktur på ett lämpligt sätt för att ständigt kunna utöka ett spels karta. Resultatet visar att det är möjligt att använda trädstrukturen relativt bra till växande kartor men att det inte är att rekommendera till spel, eftersom strukturen i sig är en omväg. I samband med denna karta skapades en slumpmässig path-generator som skulle kunna användas till att generellt skapa slumpmässiga kartor i spel. För att se vad försvårigheter man stöter på när man utvecklar en slumpad map-generator, vilket visade sig vara svårt i och med att man hittade många specialfall..

Realisering av en modulär skogsmaskin - En skalmodell

Wood for commercial use is harvested from forests using forest machines like harvesters which folds, branches and cuts trees and forwarders which transports logs to a landing area for further transport to a processing facility. Future forest machines have to be much gentler to the machine operators and forest soil than today's machines. Hence new machine solutions must be developed and tested. A practical way is to develop a physical scale model which can be used as a test-bed to incorporate different types of solutions for suspensions, cabin damping, tires and tracks, crane and overall architecture. The aim of this project was to develop such a 1:5 scale model of a forest machine, named as ?Skogbil.A scaling strategy was employed to arrive at important scale dimensions and specifications ofSkogbil which would be comparable to the full scale model.

Generell hänsyn vid avverkning : påverkan av dispens från sexveckorsregeln samt skogsägares kunskap, tankar och åsikter

The forests in Sweden have, for a long time, been managed intensively. This has led to even-aged stands with few tree species and a lack of dead wood. Therefore, general conservation measures in connection with regeneration felling are important in order to promote biodiversity. Inventories carried out by the Swedish Forest Agency, however, show that about 25 % of the felled area does not reach the level of the Forestry Act, regarding general conservation measures. The aim of my study was to see whether exemptions from the six week notice of reporting regeneration fellings (the Forest Agency demands a report six weeks in advance of fellings), affect the results of the general conservation measures taken.

Grey-sided vole and bank vole abundance in old-growth forest patches of different size and connectivity

Vole populations in northern Scandinavia vary in cycles with peaks every third or fourth year as described by the National Environmental Monitoring Programme of small mammals (NEMP). Some vole species have declined in population numbers since the NEMP started in 1971, especially the grey-sided vole (Myodes rufocanus) which is nearly extinct in the forested region. Since small mammals are an important food source for several avian and mammalian predators, the decline in vole numbers is expected to have consequences for the whole food chain, especially if other vole species start to decline in numbers. This study tried to test the hypothesis that presence and abundance of M. rufocanus (a specialist species) and Myodes glareolus (a generalist species) can be predicted by patch size and connectivity of forest patches >60 years old with a minimum of 15% pine >100years old.

Skiljer sig riskuppfattning och riskhantering mellan kvinnliga och manliga privata skogsägare? : en enkätundersökning bland privata skogsägare i Sverige

As a forest owner you always have to consider hazards and uncertainty when planning your forestry actions. The aim with this report is to test my hypothesis that there is an overall difference between men and women when it comes to perception, estimation and management of hazards/risks in forestry. I will look into if there are differences in how men and women estimate risks in production forestry from an economical point of view. The aim is also to look into if there are differences between male and female private forest owners, in how they perceive and manage hazards in connection with a possible climate change. To fulfil this aim, an inquiry survey was undertaken in three different areas of Sweden, two areas in the south and one in the north. But in this report I have evaluated the three areas as a whole.

Skogstillståndet och dess förändring i naturreservatet Lindbergska ytan i Mariestads kommun :

The aim of the study is to describe the state of the forest and changes in the Lindberg nature reserve. The study area is a nature reserve with an old coniferous forest, which has not been touched since 1950. The pines in the area have a very big diameter and are 150 ? 200 years old. The spruces are up to 150 years old.

Trakthyggesfria skogsbrukssätt : kunskap, förutsättningar och attityder

Forestry has three main aspects to take into consideration today; economical, ecological and socio-cultural. In order to reach the broad policy goals for sustainable forest management, an increased variety of management approaches are requested. Today clear-cutting is the only method used in 96 % of the managed forests in Sweden. The Swedish National Board of Forestry has therefore initiated a project in order to investigate and develop Continuous Cover Forestry (CFF). This study is a part of this project.

Viktiga egenskaper hos framgångsrika svenska skolskogar :

A substantial part of the Swedish outdoor education is being practiced in so called ?school forests?. The concept school forest was first introduced in the 1980?s by the organization Skogen i Skolan. The definition of a school forest is an area that is being used for educational purposes, over which the school and the land owner has reached an agreement of how the school may utilize it.

Alla vill beta men ingen vill bränna : skogshistoria inom Särna-Idre besparingsskog i nordvästra Dalarna

In this work I have tried to reconstruct the forest history within Särna-Idre forest common in northern Dalarna from the 19th century until present time. The Särna-Idre region has been an extensively used landscape for a long time. Pollen which indicates grazing has been found in samples orginating from the 10th century. Early travellers from the 18th and 19th centuries seem to have been passing trough a "used" landscape. Burned forests on naked ground are described as common. Also large areas are mentioned as undisturbed with lots of large trees, snags and dead wood.

Felbegreppets tillämpning på skogsplantor

Uppsatsen behandlar felbegreppets tillämpning på skogsplantor. Lagstiftningen inom området skog och skogsplantor är relativt omfattande men skogsplantor är biologiska produkter varför lagstiftning inte helt kan förhindra att skador eller sjukdomar ändå uppstår. Det är helt enkelt inte möjligt att framställa skogplantor utan att en viss andel av dem är behäftade med fel. Då det är en mängd sammanverkande faktorer som kan bidra till skador eller plantors död kan det vara svårt att fastställa om orsaken till skadan/plantdöden var att hänföra till plantorna eller faktorer i uppväxtmiljön. Svårigheter att fastställa orsaken kommer därför bidra till svårigheter för skogsägarna i samband med reklamation.

Data och metodik för utbytesberäkning - en studie på Medelpads Skogsförvaltning

To manage the industry?s need of wood assortments in a optimal and cost effective way the forest companies need to have knowledge of the actual standing volume and the yield of the planned clear cuts. The mean volume of the trunk is also important since it is important for the contractors prices. Today the total volume are estimated either with Näslund (1940) or Brandels (1990) functions of volumes, and the yield is estimated with Rune Ollas (1980) function for trunks and stands. The purpose of this study has been to answer the following questions: How good is the yield forecast with data collected with currently used methods? How well can the yield forecasts became with data collected according to the instructions? How well can the yield forecast be with data collected according to the instruction and calculated with the program Aptan for theoretical bucking? The study has been initiated and financed by SCA Skog AB.The material consisted of a number of randomly selected objects ready for clear cut.

Gödslingsstrategins inverkan på Holmen Skog, Umeå distrikt

This thesis analyzes the effects of different fertilization strategies on forest management at Holmen Skog in Umeå district. Harvesting volumes, net present values and fertilization intensity are presented for each fertilization scenario. The planning reserve (percentage area older than minimum final felling age) was also analyzed in this study.The thesis covers the analysis of five different fertilization scenarios, varying in fertilization intensity, from no fertilization at all, to fertilization at every harvesting operation (thinning or final felling). A sub-study was also carried out so the reader in detail can see how the different fertilization scenarios affect individual forest stands of different nature. The analysis has been done with the planning tool PlanWise, which is an application of the Heureka analysis and planning system.

Slumpmässigt genererade nivåer

When a videogame is being played it is rarely a static experience. A videogame can consist of various systems that affect each other in an unpredictable manner which makes the player experience unique for every player.Throughout the years developers of games have used random chance in a games programming to affect the user experience. Sometimes it even goes so far as to having entire games based around the idea of the game itself randomly generating content for a player to experience.This paper will examine randomly generated content in videogames. It will take examples from existing ones and describe how they use it, and reason regarding the benefits and drawbacks of having random chance affect the user experience.The paper will step-by-step examine the purpose of various commonly occurring objects and features of a typical dungeon in an adventure videogame. It will reason around their purpose, and figure out ways to use them in a structured  manner so that we can guarantee that there will be no deadlocks that the player can't overcome.This will range from the environments in rooms, the shape of them, to the objects and creatures that inhabit them, such as locked doors, keys, and bosses.

Att restaurera forna tiders beståndsstruktur : ett exempel från Jämtgaveln

In Sweden today so-called "prescribed nature conservation burning" is performed due to the change in silvicultural law, certification and an increased knowledge regarding the field of fire in the forest landscape. The aim is to re-create structures and qualities made by the fire regimes of the past, though on a much smaller geographical scale. The structures and qualities to be re-created are for example broad leaf stands, trees with large diameter, heterogeneous stands regarding variables such as age and diameter. If we increase our knowledge of the constitution of forests characterized by fire, then we will be able to set goals for what achievements to reach both on landscape scale and stand scale. The aim of this paper is to try to describe how a stand from the past was composed regarding mainly the spatial arrangement and compare it with the stand of today in the same place. This to be done by using relict material, that is stumps and dead standing trees.

Vegetationsutveckling och brandhistorik i Tyresta under 9000 år : en pollenanalytisk studie av en skvattramtallmyr i Tyresta nationalpark, Södermanland

Analyses of pollen and charcoal in peat cores, together with age-structure data of Pinus sylvestris from a Ledum-Pinus-mire in the Tyresta National Park (south-east Sweden) show the regional vegetation succession and fire history over the last 9000 years. Five major stages of mire development are identified: 1. Lake (c 7000-6400 cal BC); 2. Wet fen (c 6400-6000 cal BC); 3. Deciduous fen (c 6000 cal BC to c cal AD 700); 4.

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