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1233 Uppsatser om Load-carrying capacity - Sida 18 av 83
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.
Förändringar i markanvändning över tid och dess påverkan på vattenkvalitet
The EU Water Framework Directive has led that management follows the boundaries of natural catchments.The Swedish waters suffer from a nutrient overload that originates mainly from diffuse sources such as agriculture and the subcatchment of Hackstabäcken in Vallentuna Kommun, just north of Stockholm, has been chosen for this study because of its high nutrient load and because it has undergone obvious changes in land use through the years.In this study, the land use in 1902 is compared with the land use in 2011 in order to investigate if it has influenced the ability of the landscape to produce ecosystem services related to nutrient removal. These services will continue to be produced as long as the system is stable and resilient, but when landuse changes and manure from horses increases it will lead to disturbances that can convert a system from one regime in to a completely different one. That will result in loss, or degradation, of ecosystem services such as denitrification, phosphor sedimentation and adsorption, vegetation uptake and infiltration.The results of this study are based upon area calculations of landuse from old maps from 1902 and 2011. Through these maps it becomes clear that the forests in Hackstabäcken, has increased with 170 ha together with an urbanization of 311 ha, at the same time as wetlands and arable land has diminished and lakes has suffered from reductions. Wetlands have been reduced with 76 ha and the ones remaining are of insufficient quality from a nutrient removal perspective.Data from 1902 and 2011 regarding number of horses and bovines indicated a decrease in bovines and an increase in horses.
Forestry supply chains : preparing for the unpredictable
Forestry supply chains are a significant part of the Swedish economy. These supply chains are highly susceptible to storms damage. In late 2013 Sweden was hit by multiple storms. This leads to the possibility to research how supply chains react to the shocks that storms cause. The aim of this thesis is to research the costs that storms increase, the actions that are taken within the forestry supply chain, as well as possible benefactors from storms.
This thesis bases on previous work on supply chain mapping and cost theories.
Optimering av påstorkning : Från behov till färdig konstruktion
This thesis describes the redesign ofequipment designed for drying bags thatis used in Fresenius Kabis´manufacturing of their nutritionmedicine in Uppsala. The need of thistask arise during the start of thedevelopment of a new packaging line werethis equipment were meant to be used. Anevaluation of the bagdryers capacity andcapability was necessary.The work started with gathering ofinformation from suppliers of the usedcomponents and from the responsibleengineers for this equipment. Aneducation to learn how the equipmentworked and how to operate it were taken.That was followed by the creation of astudy plan were the tests were plannedto test different parameters effect onthe drying result and to see if thebagdryer managed to handle the bags ofthe correct format in the pace that theequipment should be designed for.The test results detected a need ofdesigning a unit with a function thatholds the bags in place while passingthrough the dryer in order to attainhigh quality results. The results werelater used for optimization of thedesign.
Strötorvsanvändning i djurstallar : en litteraturgenomgång
Peat litter has been used in animal houses for a long time. Because of its good ability to absorb liquid and nutrients from the manure it can create a dry surface for animals and a valuable manure product. Through changes in agricultural practises the use of peat litter has diminished and is to a great extent replaced by straw, sawdust and cutter shavings although Sweden is rich in peat-findings.
The aim of this work was to summarize the presented knowledge about the used of peat
litter, techniques, advantages and disadvantages and to compare with other commonly
used litter materials. Articles on peat litter have been searched for in magazines, databases and books at SLU library. Visits to peat industries, interviews with peat producers and with peat researchers contributed to the material.
Peat is not a uniformly material.
Betong - Förvånansvärt lättflytande!
Concrete is a very common construction material. It´s characteristics are strength, durability and formablility. Superplasticizer is a common admixture, which changes the properties of concrete.
Today (spring 2007) there are no certian mathematical methods to calculate the required percentage of this admixture needed to give the necessary set slump flow in the overall concrete recipe.
Concrete batching companies must therefor experiment with different amount of superplasticizer in order to meet the specified slump and strength.
The purpose og this report is to investigate if any mathematical relation can be established between the amount of superplasticizer used and the slump flow achieved.
After carrying out some practical experiments using four different superplasticizers a direct relationship can be establish between the percentage of admixture used and the slump/flowability achieved. Unfortunatly at present due to the numerous variables, the calculation of mathematical formula can not be achieved..
Enkät för skattning av 8-åriga barns fysiska aktivitet : En valideringsstudie. Frågor ur SIH-enkäten jämförda med referensmetoden accelerometri
AimTo validate the STOPP-8-questionnaire (S8Q), containing items from the SIH-questionnaire, against the criterion method accelerometry to estimate its capacity to assess 8 year old Swedish children?s physical activity (PA). Can it assess children?s physical activity? Can it differentiate the active children from the sedentary? If the answer is yes, how well can it do so? MethodData was collected during fall and winter the school year of 2008 - 2009 via the project STOPP-8. Out of 676 children at 12 schools in Stockholm area, 155 (boys n=72, girls n=83) provided complete questionnaire data and wore an accelerometer (Actiwatch 4) during 7 consecutive days which provided data for mean and median activity, time spent sedentary, in moderate to vigorous PA and vigorous PA.
Att göra förändring: en studie av ledarskap och organisation vid förändringsarbete
The purpose of this essay is to analyse how the leadership and the structure of the organization affect the process of changes within a specific department in Lunds kommun socialdepartment, from the director of social work to the co-workers at Utredningsenheten för ungdom och familj. We aim to answer the following questions;How does the structure of organisation affect the process of change?What do the co-workers and the leaders believe is the best way to engage the co-workers in the change?How does the leaders view their own leadership in the process of change?How does the co-workers view the leadership in the process of change?How does the leadership affect the process of change?To develop an organisation and to make it a functional, change is a necessity. The leaders are they who create the change but the co-workers are they who make it happen. In the process of change, leadership and the leaders capacity to create motivation for the co-workers, is therefore a matter that is decisive to its success.This is a study based on a qualitative method, where the interview is the main source of empirical material.
Intranät - en kunskapskälla i arbetet?
The ambition with this study is to look into and create an understanding for
how an intranet can work as a support system in work processes in capacity as a
source of knowledge. We want to enhance the understanding for which kind of
knowledge that can be coded in and transmitted by an intranet, and which that
is lost in this process. We also want to clarify what it takes to get this
knowledge, in collaboration with the intranet, to support the work in an
organization.
It is a qualitative case study at a Swedish bank. It consisted of semi
standardized, half structured interviews with five people in one of the bank?s
local offices.
Stadsodling som begrepp i Sverige - bakgrund, nulägesbeskrivning och tänkbar utveckling
The structural rationalization of rural firms in Sweden has led to many new creative ways of developing companies. The agriculture sector is characterized by the need of capital in form of buildings, labor and inventory. The rationalization process has led to free capacity in rural firms when new technology make buildings and inventory not longer necessary for the production process. To get a better cost coverage this free capacity can be used to start-up new business areas that help the rural firm to growth.The study aims to identify factors that motives entrepreneurs in rural firms to develop new business areas. The purpose is also to analyze driving forces that lies behind development of rural firms and the forces that support or not support development in rural firms.The study is built upon five cases that all can be categorized as firms with different size and orientation.
Sveriges potential för elproduktion från takmonterade solceller : Teoretisk, teknisk och ekonomisk analys
The Swedish potential of electricity production from roof mounted solar panels has been determined in three steps: accessing the existing roof top areas, simulating the amount of electricity solar panels can produce on these areas and finally analyzing how large the necessary economical change is to make the solar cells profitable.The total existing amount of roof top areas are 319 square kilometers and the area distribution follows the distribution of people. This leads to an installed power of 47,9 GW which are expected to produce 49,0 TWh electricity per year. If the quality of the electricity is prioritized the highest the power is reduced to 3,7 GW, generating 3,8 TWh yearly, but if the hosting capacity is calculated from Sweden?s total electricity need, the capacity is 42 TWh per year.Today, solar panels are not profitable in Sweden for houses, even though there is a subsidy of 35 % of the investment costs, discounted in 25 years. The profitability is calculated with a cost of capital of 5 %, a price on electricity of 1 SEK/kWh and an investment cost of 20 SEK/Wp.
Ungdom, utanförskap och bostadsområdet som reservat. En samtidsorienterad studie av stadsdelen Hovsjö i Södertälje stad
This study is an investigation of a sub community within the community of Hovsjö. The local government has financed a project in Hovsjö which is intended to bring about positive development. The prior object of this paper is to describe the project, it?s planning, it?s methods, it?s carrying through, and it?s goals. This study presents the district of Hovsjö in Södertälje.
Den goda webbplatsen : ? en undersökning om användbarhet med fokus på liseberg.se
Usability is a way to study how good a website is which is what our research builds upon. On a mission from Liseberg our purpose is to find out if their website liseberg.se is good from a user?s perspective. Our way of carrying this out where grounded upon a qualitative study through observations and following interviews with a number of participants. By compositing tools of method we have started with the theories descriptions of usability tests and we have also used the theories to be able to reflect around and to understand the results from the tests.
Makt i klassrummet : En maktanalys av relationen mellan lärare och elev
This essay is about power in the classroom. It is about the power dimension of the student-teacher relationships that arise in that space. The overall aim has been to investigate which categories are fruitful in a power analysis of these relationships. My aim has therefore been to develop power categories and to use them to identify and to categorise cases of power interaction that take place between those particular actors in that particular setting.In order to gather material for my study I have both read literature that approaches the study of the student-teacher relationships from a power perspective and done a series of observations in a high school.My theoretical frame comprises a concept of power and a series of power categories. These categories include strength, authority, inducement, coercion, violence, resistance as well as to possess power, to have power, to exert power, the scope of power and the base of power.
Mineraliska material som reaktiva filter för avskiljning av tungmetaller från dagvatten
Highly polluted urban storm water from e.g. highways can contain large amounts of heavy metals that may cause harm if they are discharged into recipients. To remove the heavy metals a possible low-cost method that does not require much maintenance, could be the use of reactive filters with filter materials consisting of industrial residues or other cheap mineral based materials. Dissolved metal ions are removed by reactive filters through the processes of ions binding to active sites on the surface of the filter materials, or by formation of insoluble precipitates.The ability of CaO-treated granulated blast-furnace slag, iron oxide coated sand, olivine and nepheline to remove seven heavy metals (Cr, Cd, Cu, Ni, Zn, Pb and Hg) from urban storm water was studied. Initially batch experiments were performed where the effect of pH, dissolved organic carbon (DOC) and dissolved ions on the adsorption efficiency was studied.