Heavy duty vehicles often have problems with traction during the winter periods. For vehicles that can lift tag axles it is possible to increase the normal force on the driven axle by lifting one or more tag axles, this will then increase the propulsive force of friction. This however increases wear on both road and vehicle. A possibility to reduce the wear while achieving nearly equivalent traction compared to lifted tag axles is to allow the vehicle to regulate the normal force by lowering the pressure in the air suspension associated with the tag axles or by the lifting of these axles. The vehicle would then by itself be able to set just the right amount of normal force on the drive wheels to avoid unnecessarily high normal forces while maintaining sufficient traction.The purpose of the report is to find out which parameters affect heavy duty vehicles when driving on slippery slopes and how traction can be improved.

Syftet med denna uppsats var att undersöka vilka faktorer som påverkar hur förvärvsarbetande människor i Gävle använder sig av bil och aktiv transport när de transporterar sig till destinationer inom staden. Tio personer, fem butiksbiträden och fem lärare, intervjuades angående deras transportvanor och resonemang kring valet av transportsätt.Resultatet visade att aktiv transport var det vanligaste transportsättet till arbete, träning och butiker i centrum medan bilen var det vanligaste transportsättet till mataffären och destinationer på längre avstånd från hemmet. Avståndet till destinationen, tiden det tar att transportera sig, transport av eventuella varor, bekvämlighet, intresse av motion och rekreation, årstid, väder samt synen på ekonomi och miljö var faktorer som påverkade om deltagarna valde att transportera sig med bil eller aktiv transport. Definitionen på de olika faktorerna varierade mellan deltagarna, vilket kan tyda på att det är den personliga uppfattningen om de olika faktorerna som avgör vilket transportsätt som väljs. Det framkom ingen märkbar skillnad i resvanor mellan deltagare med olika utbildning och arbete..

The student project Elba at KTH started in 2011 and is a project where a battery driven prototype car is developed. The vehicle competes in Eco Shell Marathon in Rotterdam, Holland. In this competition the vehicle that travels a certain distance including several starts and stops with the lowest energy consumption wins. To minimize the consumption is therefore very important, which requires knowledge of the vehicles energy losses.A vehicle's energy losses depends on several factors and can be divided into the powertrain efficiency and the driving resistance. The driving resistance can then be divided in to rolling and air resistance, if smaller losses like vibrations are ignored.

Msc in Logistics and Transport Management.

Today when new and harder demands on CO2 emissions are developed, vehicle manufacturers must work to develop new engine solutions to new kinds of fuels to replace fossil fuels. A fuel that could be applied is hydrogen. When hydrogen is combusted only water vapor occurs. Hydrogen is known to be explosive and flammable. These properties are both good and bad for combustion.

Swedish sawmills of today suffer from unsatisfying economy with high costs and low benefits. The economical result depends on how well the sawmill can use their raw material. Iggesund Timber AB, a sawmill in the Holmen group, produces a large amount is enduse orientated products for the woodworking industry. Therefore the aim of this student thesis was to investigate the possibility of automatic enduse orientated quality grading of Scots Pine (Pinus sylvestris) saw logs by using a gamma-ray log scanner. Iggesund Timber AB has the possibility to grade logs automatically with TINA, a two way gamma-ray log scanner. Grading and classification of Scots Pine logs in Sweden today are mainly manual but can in some rare cases be automatic.

Profit in first commercial thinnings of today is hard to achieve. This is because of prevailing pulpwood prices and because of high costs of logging and transport. To reduce these costs higher productivity is advocated. One way to increase the productivity is the use of multi-tree handling harvester heads. The aim of this study was to calculate logging and transport costs in first thinnings, where multi-tree handling has been used.

Restrictions in nature conservations are increasing the influence of forest management. Nobel broadleaved forests are more influenced than other forests, because they are considered to be more valuable than other forest types in Skåne. There has been a lack of knowledge about the amount that is set-aside for nature conservation and what types of forest that is concerned. These are the main questions to be answered in this thesis. Moreover has the timber quality been compared between set-aside and non-set-aside areas since it affect the financial conditions for the forestry in nobel broadleved forests. The last asked question deals with the financial consequences of set-aside.

In 1997, the Swedish parliament adopted a decision on Vision Zero (nollvision) in the road and transport system. Vision Zero means that no one should be killed or seriously injured in traffic accidents in the road transport system (Prop. 2003/04: 160). For the Transport Administration in Sweden (Trafikverket), this means increased demands on security and signage at road work sites around the country. This in turn means increased demands on the contractors that carry out road work for the Transport Administration.

High demands are set on all equipment used in emergency service work, where small margins can be the distinguishing factor between life and death during a rescue operation. It is important that tools such as ladders quickly and easily can be dismounted from a vehicle and still satisfy the regulatory requirements for securing loads during transport. The existing solution for getting ladders down from the roof of a fire engine requires a large manual effort from the user in an ergonomically unsound posture.In this degree project a new ladder holder is developed with focus on the user to solve the ergonomic problems and at the same time create a more compact design that can be adapted to several different types of ladders. After an initial pre-study with user-interviews and measurement of forces and distances a set of requirements was formulated that came to govern the project's direction. Creative methods were used to generate concepts that improved the function and through design solutions, calculations and testing in CAD a base for manufacturing of a new product was created.The result is a completely new type of ladder holder that minimizes the user's manual effort and simplifies the securing of ladders in the holder.

Due to the new demands put upon combat vehicles of today the development quickly strives for-ward. With developers and experts across the globe working to meet the needs of tomorrows armies. The question we ask ourselves is what will be the characteristics of these vehicles. In order to be able to categorize combat vehicle and analyze its characteristics we use the principles of war. Based on J.F.C Fullers theory from the early 19 hundreds that anything can be analysed using these principles, through a modern interpretation of the Swedish army, we can categorise the present and future abilities of combat vehicles.

Sweden have 419 000 km road in the country and about half of these roads is forestroads. The forest road net most important mission is to make it possible to deliver wood from the forest to the industries. With a raw material that is spread over a large area the road network is important. Each year has the forest road network been extended with about 1 700 km new roads. To decide if a new road is to be built different forest road cost estimation models has been used.

The purpose of the present study was to examine effects of driver, vehicle, and environment characteristics on Collision Warning System (CWS) design. One hypothesis was made that the capability of collision avoidance would not be same among a driver, vehicle, and environment group with different characteristics. Accident analysis and quantitative analysis was used to examine this hypothesis in terms of ?risk? and ?safety margin? respectively. Rear-end collision had a stronger focus in the present study.

Holmen Skog has in some places in their operation area access to timber trucks with centre mounted scrapers. They make transportation more flexible and reduce reliance on contractors for road maintenance. The trucks with centre mounted scrapers have a higher tare weight, making them less productive and therefore they receive compensation with a 0.75 % increase on transportation price. The purpose of this study was to investigate what actions a timber truck with centre mounted scraper can perform with acceptable quality in winter, and to examine if it is an economically profitable solution for the truck operator and charterer. The study was done in three stages; interviews, performance analysis of the transportations carried out and an economic analysis with the help of Sven Erik Gilles spreadsheet tool. The study included the districts Delsbo and Hudiksvall.

Under de senaste tio åren har antalet hästsportsevenemang ökat drastiskt, både internationellt och i Sverige. Det ökade antalet hästsportsevenemang visar på ett ökat intresse för hästsport och hästar vilket i sin tur föranlett en ökning i transport av häst. Vetenskaplig litteratur inom ämnet är knapp och det som finns berör vanligen fysiologiska mätningar för att uppmäta stress under transport. För att få en uppfattning om hur marktransporter av häst går till i Sverige och skapa en kunskapsbas för framtida studier utfördes en webbaserad enkätstudie. Enkäten låg ute i 6 dagar och 1013 personer svarade varav 906 stycken kunde analyseras.