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1010 Uppsatser om Random Forest - Sida 33 av 68

Röjningsbenägenheten bland privata skogsägare : en enkätundersökning bland medlemmar i SÖDRA

The intensity of cleaning declined dramatically in the early 1990?s in the Swedish forests. Recession, an economic depressed forestry and the new law of silviculture from 1993, where the duty of cleaning was removed have been considered as sources to the decline. This has led to a situation where huge areas of forests are untouched, which can lead to negative effects for those stands in the future. The purpose of this thesis was to find out how the individual landowner acts and feel when it concerns cleaning activities. Has the landowner noticed Södra?s campaigns about cleaning and what sort of measure should Södra implement to increase the members? cleaning activity? The thesis is based on a opinion poll made through a random draw among all Södra?s members.

Kan markfuktighetskartor användas för att hitta skogsmark med hög bonitet? : ett gis-baserat försök med dtw-index och laserskannad övre höjd

The depth-to-water-index (DTW-index) is derived from digital elevation models (DEM) to map soil wetness, in terms of distance from soil surface to the ground water table. The aim of this GIS based study was to investigate the existence of a relationship between DTW-index and forest site productivity (SP). The belief of such an assumed relationship was based on knowledge that the ground water level is related to site properties that can either promote or impede tree growth. Data primarily comprised rasters of the Krycklan catchment in northern Sweden and depicted DTW-index and a laser scanned vegetation height. The 100th height percentile of each pixel in the vegetation raster was assumed to mirror the top-height, letting it act as a relative measure of SP within a delineated area of equal stand age.

Däck-mark Interaktion hos skogsmaskiner

The most predominant method for forest harvesting in Sweden is the cut-to-length method based on two-machines, a harvester that fells trees and cut them in a predefined length, and a forwarder which transports logs to a landing area for further transport to a processing facility. New machine solutions have to be much gentler to the ground than today?s machines. To be able to develop a forestry machine that preserves the terrain requires a proper understanding of the interaction between tire and soil.The goal of the project is to contribute to the existing knowledge of forest machine tire-soil interaction and to develop a tire-soil model that enables dynamic simulations of forest machines operating in rough terrain. The modeling has especially been focused on the interaction between tires and soft ground.A comparison of theoretical data of different WES-based terrain interaction models and a comparison test data from a full scale field test is presented.

Att veta Gudarnas hemlighet : En sårbarhetsanalys av omständigheterna kring stormen Gudrun med pressure and release modellen

The concept of vulnerability is the capacity or the sensitivity to become damaged. Vulnerability are characterized by one or more of the following terms; a system´s sensitivity to exposure to shock, stress or interference, the state of the system in relations to a threshold of damages, and the system´s ability to adapt to the changing circumstances. Vulnerability in this study is referring to the sensitivity of the circumstances that lead to sustainable livelihood that can´t be maintain and that there is an inability to cope with and manage stress. The choice of making a study in this area is based on that action needs to be taken to moderate the vulnerable aspects of society, in this respect in relations to storms. Analyzes of the social vulnerability to climate change or natural events is needed for effective actions.

Vad orsakar skador på kvarstående träd vid mekaniserad gallring - en intervjustudie

This thesis includes a review of scientific studies of tree injuries following mechanized thinning. Interviews have been made with drivers of single grip harvesters and forwarders in forest thinning and a number of essential factors have been identified as the most important to take into account in order to minimize and/orprevent injuries to stems and roots of remaining trees..

Advantages and disadvantages of different observation methods on a troop of wild olive baboons at a river in Southern Kenya

Every observation method has its advantages and disadvantages and a well-adopted method gives more reliable results. Factors affecting the choice of the most appropriate methods for recording foraging behaviours include species, group size, environment, seasons and age. The focus for this study was to determine which method is most appropriate for studying the foraging behaviour of a troop of 89 olive baboons (Papio anubis) living in a riverine forest by the Southern Ewaso Ng'iro River by Lale'enok Resource Centre in Kenya. To determine this, a literature study was carried out to compare methods from monkeys and apes. I found instantaneous sampling was the most common method with intervals of 5 minutes in most cited studies.

Rörelsebaserad kommunikation i mobila ad hoc-nätverk

I många nätverk antas det att någon form av fix infrastruktur existerar och att nätverkets olika noder kan använda denna för att kommunicera med varandra. I ett ad hoc-nätverk antar man att det inte finns någon fix infrastruktur och att noderna måste använda varandra för att kunna kommunicera. Ett exempel på ett ad hoc-nätverk kan vara bärbara datorer sammankopplade med infraröda länkar under ett möte. När ad hoc-nätverket är mobilt innebär det att noderna rör sig.I detta arbete har de tre protokollen Epidemic, GeoMean och GeoMove tillsammans med de två rörelsemodellerna Waypoint och den utökade slumpmässiga vandringen implementerats i en nyskriven simulator för denna typ av nätverk.De två Geo-protokollen är nyutvecklade och syftar till att använda geografisk information för att underlätta kommunikationen i denna kategori av nätverk tillsammans med den nya utvidgade slumpmässiga vandringsmodellen..

Modellbaserad ekoföljning i vätskefyllda tankar

This thesis discusses model based tracking of radar echoes in tanks with liquid content. The errors in the measurements are not always random in these cases, and the interference that occurs when nearby echoes moves in relation to each other makes tracking difficult. The tracking problem can be broken down to four parts; track initiation, track destruction, association of the measured echoes to the tracks and to update the tracks with the associated echoes. The radar measurement is primarily made on the surface. However, additional echoes from the tank floor or other structures and double bounces are normally present.

Metoder för att undersöka effekterna av naturvårdshänsynen i skogsbruket, efter den senaste skogsvårdslagenMetoder för att undersöka effekterna av naturvårdshänsynen i skogsbruket, efter den senaste skogsvårdslagen.

In 1994 a new Forestry Act was accepted in Sweden. One of the aims of the law is to raise consideration forpreservation of biodiversity. Since the new law got accepted and some time has passed, there now lie someinterest in examining whether the law has been effective towards its purpose. Methods suitable for analysishave been examined during this study. The content of this pilot study is based around five parameters whichcan be used to validate the effects of the new law.

Jämställdhet åt skogen?! En studie som utreder anledningarna till att kvinnorna slutar som skogsinspektorer

The forest owner cooperative has observed difficulties with keeping women as forest advisers/ buyers. This is a problem because the organisation wish to have both men?s and women?s qualifications. The organisation?s purpose in their equality and multiplicity plan is to increase the knowledge and awareness of equality and multiplicity, increase the credibility to the members and customers, and to be well prepared for the future need of qualifications. The purpose of this paper is to identify if there are any conditions that may limit female employees at this particular service.

Evaluation of an ectomycorrhizal macrofungi as an indicator species of high conservation value pine-heath forests in northern Sweden

Since the 1950s, the development of modern rotation forestry in boreal Fennoscandia has resulted in a severe reduction of older forests, and a high degree of fragmentation among the small patches that remains of old forest. In Sweden, when performing conservation value assessments in order to identify and preserve the remaining forest habitats, the government authorities use to a significant extent a set of indicator species that indicate habitats of high biological conservation value. One species considered to indicate high conservation values in pine-heath forests is the red-listed ectomycorrhizal (EM) macrofungi Sarcodon scabrosus (Fr.) P. Karst. In the present study, the validity of using S.

Härliga hagar och skrämmande skogar : om våra känslor för landskapet och vad de beror på

Do our imaginations of real landscapes get affected by works of art such as paintings, myths and literature? They often give very colourful descriptions in words as well as pictures. Do they actually change our feelings for the landscapes we are in and carry around as images inside? Close your eyes and take a few deep breaths. Imagine that you are leaning against a wooden fence a mild summer evening.

Är bor nödvändigt vid skogsgödsling i Sverige?

This thesis has been made on behalf of SCA Skog AB to assess the need of boron in Swedishforest fertilization. Boron has been added to Swedish forest fertilizers since the beginning of the1980s. This makes the fertilizers more expensive and therefore has the necessity of boron inSwedish forest fertilization been raised.The Swedish bedrock generally contains small amounts of boron. The boron in the bedrock istightly bound to the mineral tourmaline and mostly unavailable for plants. This leads to that thecontribution of boron to the soil from weathering is very low besides soils with marinesediments.

Val av område och områdesskydd för Natura 2000 med skogshabitat : En jämförande studie av fyra län i Sverige

The Natura 2000 Network is one of the European Unions many tools concerning nature conservation, and is without comparison the premier contribution when it comes to halting the loss of biodiversity. This essay is a case study on how the regional work with the Natura 2000-network has been carried out in four different counties. These counties are Södermanland, Västernorrland, Jämtland and Örebro. They have been compared based on the theoretical concept of sustainable development. This essay describes how the officials in the County Administrations view the regional implementation of Natura 2000 when it comes to the selection of Natura 2000-sites with forest habitats and the creation of an additional protective measure.

Planering av väginvesteringar :

The problems around and the planning of wood flow is some of the most complex issues in the forest-sector. The experience and overview of the single employees is crucial for the possibility of correct tactical and economical decision-making. The increasing demand of savings and shorter reaction-times with greater flexibility in the wood-supply-chain, makes solutions and aids for improved effectiveness in the work and processes according to wood-flow urgent. Holmen Skog is starting to develop a new forest-road-management-system. The system will facilitate the work according to construction, improvements and updating the standard of roads.

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