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93 Uppsatser om Mountainous terrain - Sida 2 av 7

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.

Samiskt skogsutnyttjande, dimensionsavverkningar och naturvärden : skogshistorisk analys i block 5, Pakko kronopark i Norrbotten

In order to understand the human impact on today?s remaining ?virgin? forest and to develop sensible management strategies for future reserves, it is necessary to know how these forests have developed. This knowledge can be gained by using forest history analysis. here are large areas of forests still untouched by modern forestry in the mountainous region in the county of Norrbotten. These forests are highly interesting study objects from an ecological and historical point of view.

Utvärdering och implementering av automatiska farthållare i fordonssimulator

Vehicle simulators are becoming more common in vehicle industries. Company earns lot of money on simulations instead of real tests. Real tests are necessary but not made so extensively as before.In this thesis the building of an vehice simulator will be described and a comparison between three different cruise controls. The three cruise controls are PI-regulator, a regulator who regulates after positions in the terrain and a MPC-regulator. The reason for choosing this three is to see the difference between simple regulation and more complex regulation with respect to fuel consumption, travel time and complexity.The vehicle simulator is made in Matlab/Simulink, Visual Studio and Open Scene Graph.

Utvärdering av metoder för framställning och kontroll av digitala terrängmodeller

Today there are many applications of digital terrain models (DTM) and the requirements of low uncertainty increases. Most of the DTM are produced with Global Navigation Satellite System (GNSS), terrestrial laser scanning (TLS), airborne laser scanning (ALS) and total stations. Guidelines for the preparation and verification of DTM are found in Swedish Standards Institute ? Technical Specifications (SIS-TS) 21144:2007 and SIS-TS 21145:2007. These were defined in collaboration between Swedish National Rail Administration, Banverket, and Swedish Road Administration, Vägverket, to satisfy the needs of requirement formulations in the production of DTM planning, design and construction. The purpose of this paper is to produce and control DTM over Åkermans kulle, located west of the University of Gävle, according to SIS TS 21144:2007 using GNSS with network-RTK, TLS and ALS.

Markberedning med traktorgrävare, prestation och kostnad

This study investigated the performance and cost of scarification with a tractormounted excavator. Due to variations in terrain conditions the performance variedbetween 0.08 and 0.11 ha/E15h and, with a machine cost of 366 SEK/h, the cost ofscarification varied between 3 330 and 4 750 SEK/ha..

Konceptstudie av drivmodul till bandskotare med hybriddrift

BAE Systems Hägglunds has a long history of producing high performance terrain tracked vehicles (mostly for military applications), and they are now aiming at developing a tracked forwarder with similar techniques.The forwarder will be of series hybrid type where a diesel engine via a generator will power the motors (one for each drive wheel). Thanks to individually controlled motors and the gentle rubber tracks, this forwarder is calculated to have a considerably higher average speed in the terrain and to be more gentle to the soil. The forwarder with a weight of 11 metric tons and a load capacity of 15 metric tons is specified to have an average working speed of 7-10 km/h, a top speed in terrain of 15 km/h and a top speed on roads of 40 km/h.This master?s thesis aims at developing a conceptual design of the forwarder?s drive module which includes electric motor, gear unit, brake and drive wheel.To investigate if the requirements can be fulfilled a study of the dimensioning loading scenarios has been carried out. The resulting needs regarding the torque has been considered in order to determine the required gear ratios for different motor options.

Utveckling av Trailplate - En skyddande innersula

The project aimed to develop a protective and stabilizing insole called Trailplate for soft andlight shoes. The demand came primarily from off-road runners in France, Switzerland, andAustria. The project was carried out at Icebug, a company that develops shoes mainly forrough terrain. The main focus has been on the trailplate which is designed to fit severaldifferent shoes.Torsional stiffness and bending resistance were the main objectives. To improve the existinginsole, a material with the right features was required.

Spatial TDMA in Ad Hoc Networks with Antenna Arrays

In modern military operations the requirements of transmitting large amounts of information have increased substantially during the last decade. This increases the demand for high-capacity radio networks. It is also very important that military decisions are made on recent and correct information and this implies that low and known delays are required. The existing military radio ommunications, within the Swedish army, do not meet the requirements for capacity and delay. We have investigated how the capacity and average delay can be improved in an Ad Hoc network with STDMA by using antenna arrays.

Brown bear (Ursus arctos) den site concealment in relation to human activity in Scandinavia

As a hibernating species, the brown bear spend most of the winter months in a den as astrategy to avoid unfavorable conditions. The denning period is a vulnerable time for bears,making them unable to flee disturbances without losing valuable amounts of energy. Brownbears' wariness of humans and avoidance of anthropogenic disturbance often steer denningbears away from human infrastructure, and bears thereby avoid possible disturbance and itsassociated energetic costs. This study was carried out to test the hypothesis that bearsdenning closer to infrastructure select more covered den sites to compensate for the closedistance. Dens from 32 individuals were visited and analyzed in terms of sighting distance(a measurement for den horizontal cover) and habitat ruggedness, in relation to distances toinfrastructure.

En fordonsförares upplevelse av accelerationer som grund för en effektiv simuleringsmodell

Saab Aerosystems has a long tradition and a lot of competence in the field of flight simulation. Their ambition to broaden the market horizon has led to a discussion about also selling vehicle simulation solutions, both for military and civilian use.The aim of this thesis is to investigate the driver?s experiences of the accelerations he or she is exposed to whilst driving in rough terrain. The results may be used as a basis for future decisions and can act as a platform for the construction of an effective simulation model.To investigate the driver?s exposure of acceleration, some kind of dynamic simulation is needed.

Stridsvagnar i urban miljö : Ställer användning av stridsvagnssystemet i urban miljö nya krav på systemet?

Den svenska Försvarsmakten (FM) har förändrats och gått ifrån invasionsförsvar till insatsförsvar, detta har lett till att FM fokuserar på insatser utomlands och hotet skiljer sig insatser emellan. De konflikter som är aktuella idag och där de svenska styrkorna bidrar med resurser utspelar sig i länder där urban miljö med lågteknologisk motståndare förekommer. Motståndaren har med tiden lärt sig att hantera strider i urban miljö och uppträder i alla dimensioner. Man anser att strid i denna typ av miljö kommer att öka i framtiden. Stora nationer har stridit i urban miljö med framgång.

Räddningstjänst : Definition, ansvar och samverkan

The purpose of this legal dogmatic Bachelor Thesis is to define the legal definition of ?a rescue service? and illustrate the division of responsibilities between national authorities and the municipalities with regards to the execution of emergency response operations.?A rescue service? means the emergency response actions that national and municipal authorities are legally obliged to provide to prevent or minimise injury to people and damage to property or the environment when emergencies occur or seem imminent. In the following cases a national authority is responsible for providing the requisite rescue service:1. Search and rescue (air) ? the Swedish Civil Aviation Authority is the responsible authority;2.

Bergsbrunna södra : analys och programförslag

This final project includes an analysis and a programme proposal for the area Bergsbrunna södra. The area is situated along the railway between Uppsala ? Stockholm, just south of Uppsala city. A new railway station is planned here, which make the area attractive as residential area. There are several values to take into consideration when developing an area. An extensive analysis and valuation may define and protect different characters and values, and also find the places most suitable to build upon. The area consists of three separate characters of landscape: the wide open cultivated fields, the hilly wooden ground and the more varying little valley. There are visual, cultural, social and ecological values to preserve. The south part of the area is woods with high natural values that borders to a national park in the natural forest of Lunsen.

Odefinierade rum i bebyggd miljö : en begreppsstudie

Syftet med studien är att presentera olika begrepp med definitioner för odefinierade rum i bebyggd miljö. Rum som blivit över eller bortglömda i stadsplanering, övergivna och förfallna områden eller rum som saknar en känsla av identitet. Olika författare med olika bakgrund presenterar olika begrepp och definitioner för dessa rum. Genom litteraturstudier undersöks nio relevanta begrepp från publicerad litteratur. De undersöks utifrån frågor som behandlar författarens ursprung, verkets publiceringsår, begreppets definition, exempel som ges på odefinierade rum, hur rummen uppkommit samt hur de enligt författaren bör behandlas i planering.

Till synes orörd skog : naturvärden och kulturhistoria i Rekdalen under 400 år

Nature conservation has for a long time been founded on the assumption that high ecological values depend on low human impact. In Sweden this has led to forests with these characteristics being strictly protected from human influences. However, it is also known that historical land-use can enhance ecological values in forests. Mountainous forests in Sweden, which have not been affected by modern forestry, have for a long time been considered as untouched by people. However, forest history research has in recent years shown that even these areas have been used by people for a long period of time.

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