Automatic trimmerhead is an examination project for making an automatic trimmerhead for grass trimmers with the user and functionality in focus. Our perception is that a happy user is a user who can pick up his or her trimmer, use it and put it back to its place when the job is done. It should not be necessary to interrupt work and perform maintenance on the machine just to make it work as promised.The project has been made in collaboration with the company Husqvarna, which is one of the biggest actors dealing with garden machinery on the market. Together we determined the project goal, ?To invent, construct and test a brand new concept for how an automatic trimmerhead can look and function?.At this day there are several different automatic trimmerheads on the market, both semi and fully automatic.

Rwanda is one of the poorest countries in the world and about 70-80 % of the population lives in rural areas. The land is strongly affected by land erosion which makes it difficult for the agriculture and food production. Agroforestry is a system where tree plantation is combined with livestock- and crop production. The system provides soil fertilization and binds the soil together. Some of the trees used in agroforestry systems are also used as fodder.

Hägglunds Drives in Mellansel, Sweden, manufacture radial piston hydraulic motors foremostwithin applications in the industry. These motors have several sliding contacts, one of these, isthe contact between piston ring and cylinder bore. The radial piston hydraulic motors advantageis to produce high torque in very low rotation velocity, this result in that the maximum slidingvelocity between piston ring and cylinder bore, during the whole stroke, is very low. Theconsequence of this low sliding velocity is that the contact between piston ring and cylinderbore, during the whole stroke, is bound to the boundary lubrication regime. This result in, thatthe piston ring is exposed to wear, thus affect the service life of the complete hydraulic motor.To minimize wear of piston ring, it is essential to determine the oil film thickness between thepiston ring and cylinder bore.

The project contains a force analysis of the vertical axis wind turbine Lucia's supporting arms and a measuring device to experimentally measure the forces is made. The forces between the supporting arms and the tower are calculated theoretically and then simulated by a computere. A measuring devise is then designed to measure the forces experimentally. The forces acting on the attachment between the supporting arms and the tower is primarily the centripetal force, gravitational force and the aerodynamic forces on the rotor wings. The maximum forces were theoretically calculated and is 13.38 kN along the x-axis, -0.25 kN along the y-axis and then 0.5 kN along the z-axis.

The ammonia emissions are an environmental issue since they contribute to eutrophication. By far the largest source of ammonia emissions is manure from agriculture and should therefore be reduced. Loss of ammonia is not only negative for the environment but also to the farmer who loses nitrogen that could have been used by the crop. The focus of this study has been emissions from spreading slurry where the loss can vary widely depending on slurry-, soil-, and weather conditions. There are mainly two different ways to reduce the emissions. One is to inject or mix the slurry into the ground to avoid air contact. The other way is to use acid to reduce the pH in the slurry to a level between 5 and 6 where the equilibrium is so strongly pushed to NH4+ that hardly any NH3 can be lost.

En framgångsfaktor vid internationell tjänst är att samspelet mellan samtliga enheter fungerar friktionsfritt. Detta underlättas om samtliga enheter känner varandra innan rotation till missionsområdet. I framtiden kommer hela förband som har kontraktsanställda soldater rotera ner, dock innehar inteförbanden samtliga funktioner för att lösa alla arbetsuppgifter i missionsområdet. Vid dessa fall lånar man in enheter från andra förband. Inlåningar kan skapa friktioner mellan enheterna.

This master's theses was carried out on assignment from Stockholm Vatten AB as a part of a project developing new waste water treatment techniques. The goal of the theisis has been to evaluate an anaerobic membrane bioreactor for treatment of waste water from Hammarby Sjöstad. The bioreactor has not been heated and the main interest has been to study the gas production, power consumption and the reduction of organic matter and nutrients.The system has been completed with a reverse osmosis unit and a total of four batch runs have been made with good results. The use of reverse osmosis allows nutrient in the waste water to be reintroduced into circulation as the reverse osmosis concentrate can be used as crop nutrient.The membrane unit is of VSEP ("Vibratory Shear Enhanced Processing") type and an extensive membrane test has been conducted. This so called L-test helped determine the most suitable type of membrane for the system to allow a higher ±ux and thus lower power consumption.

All arable land in Sweden need a proper drainage for an effectively agriculture to take place. Of all arable land in Sweden, about 50% is naturally drained and 50% need artificial drainge. More than half of the tile drained area is in need of new drainage or renewed drainage. A good drainage improves farming and crop growth and increases the opportunity to achieve a high and safe harvest level. Future climate change and agriculture size rationalization will increase the need for good drainage. In this paper, two trials with three drainage distances, performed at Lanna experimental station, were analyzed using a mixed linear model.

The purpose of this degree thesis is to investigate what the English teachers in an upper sec-ondary school, think about teaching students in ability grouped classrooms. The questions that I have set out to investigate include what the teachers think about ability grouping in English, the school?s current organisation of ability groups, the pros and cons of ability grouping in English, differentiation in teaching and if students get more individualized teaching with abil-ity groups, how the teachers cooperate and what would be the optimal teaching situation in an English learning classroom.I did a lot of theoretical research on the subject and studied old essays on similar subjects. I also did some classroom observations to use as background information for my interviews. I interviewed five teachers of different sex, age, and teaching experience.

Allanblackia is a tree genus native to humid forests in West, Central and East Africa. Its fruits contain large seeds from which edible high-quality fat can be extracted. In order to create a sustainable supply chain of Allanblackia seeds, a domestication program has been initiated with the purpose to enable smallholder farmers to grow the tree as an agroforestry component and cash crop. More knowledge is required to understand the tree?s biology and possible symbioses involving soil microorganisms with plant growth enhancing poten-tial.

AbstractThis thesis was conducted by Jenny Jansson and Maria Madsen, students at the Faculty ofTechnology and Science and the Innovation and Design Engineer programme at KarlstadUniversity, during the spring 2008. The thesis covers 22,5hp for each student. AnnaHolmquist and Chandra Ahlsell at the company FOLKFORM were the ones who requestedthe theis, their company are located at Stora Skuggan in Stockholm. Tutor for this thesis wasLennar Wihk and the examiner was Monika Jakobsson of Karlstad University.The given assignment came from FOLKFORM and the aim for the thesis was to create afurther development of two already existing lamps from an earlier collection at FOLKFORM,?Jaipur? and ?Modern Times?.

Gene technology has become more and more attractive in plant breeding during the last twenty years. This is probably because it can readily improve the existing commercial cultivars that have only one or a few drawbacks by modifying one or a few genes without changing the main genetic constitution. In this regard, gene technology is more effective than conventional breeding.The aim of this project was to analyze the fruit quality of the non-transgenic apple scion ?Jonagold? grafted on non-transgenic and rolB-transgenic apple rootstocks. The rootstocks used were M9-rolB1, M9-rolB2, M26-rolB and non-transgenic controls M9 and M26.

Background: The majority of the occupational accidents and work-related diseases at Swedish workplaces occur due to poor ergonomics during lifts and transportation of objects. The most common consequence of poor ergonomic conditions is low back pain (LBP) and the risk of developing LBP increases as the mechanical loading on the intervertebral disks grows. This study has investigated the biomechanical loading in the low back during two different types of patient lifts. The first lift (lift A) is developed by Modern Arbetsteknik (MA) and the second lift (lift B) is a common lifting technique among care workers. Objectives: The aim of the study was to identify any advantages or disadvantages with MA?s lift, regarding shear and compression forces in the L5/S1 disc.

Vi har intresserat oss för hur väl kursmålen i grundskolans fysik för femte skolåret uppnås. I samband med våra funderingar kring elevers kunskapsnivå inom naturvetenskap så har media presenterat en undersökning av elevers kunskap inom naturvetenskap i år 9. Denna undersökning visade att uppnåendemålen för år 9 inte nåtts. Detta tycker vi är alarmerande och vill därför undersöka om dessa brister förekommer även i de tidigare åren, eftersom det finns uppnåendemål som ska nås i slutet av år 5. Informationsunderlaget är inhämtat från aktuella rapporter, tidskrifter, litteratur, Internet, interjuver, observation och aktuella styrdokument.

The wild boar Sus scrofa population in Sweden has increased rapidly in the last decades which has led to conflicts among stakeholders, for example due to crop damages in agriculture. Thus, there is an urgent need of quantified goals and effective strategies for wild boar management. To develop such strategies, knowledge on population dynamics is fundamental. In this study a deterministic matrix model was used to estimate population growth, based on previously published data. The exponential growth rate for a wild boar population was calculated to 1.48.