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987 Uppsatser om Soil concrete - Sida 24 av 66

Reaktionskrafter i dragarmarna på en traktors trepunktslyft : Teori och praktik

Tractors of today come equipped with a CAN-system. A CAN-system sends information from sensors to electronic control units who process the signals. The sensors measure several interesting parameters such as force, pressure and speed for various components of the tractor. This thesis discuss a force sensor which is placed in the pivot of the tractors three point linkage, the sensor measure the horizontal reaction force from the load that the tractor is exposed to. Signals from this sensor can be used to measure the force from any implement that the tractor is exposed to during an operation.

Kvantifiering och kartering av föroreningstransport inom ett avrinningsområde

The aim with my master thesis is to develop and test the applicability of methods to quantify and map solute advective travel times and pollutant transport at the catchment scale. Such quantification and mapping can increase the understanding of catchment-scale pollutant transport in general and contribute to the identification of the main sources of water pollution and the most efficient measures to reduce such pollution. The study area is the catchment of Oxundaån, about 20 km north of Stockholm. For detailed GIS modeling of water flow and catchment-scale contaminant transport in water, I´ve used new high-resolution elevation maps, land cover maps and soil maps combined with other available relevant data..

En IT-baserad plattform för skolförbättring : En kvalitativ studie av lärares informations- och erfarenhetsutbyte

This thesis has created an image of the exchange of information among teachers in the Swedish upper secondary school. The study indicates that the exchange of information seems to be limited at all levels and the exchange that takes place outside the own teaching team occurs mainly through teachers personal networks. The study also shows barriers that may exist and the opportunities that an increased exchange may generate. From the picture that the empirical material provides and the theory that is presented a discussion is made around how IT can best support the organizational learning in schools. A concrete proposal is that at national level an IT platform should be created, which primarily focuses on materials that are created by its users and has an open architecture with a single login..

Järnets förekomst i grundvattnet i isälvsavlagringar i Dalarna : Bakgrundshalter och rörmaterialets inverkan vid grundvattenprovtagning

A study has been performed that investigates the variation of iron content in groundwater.The study was initiated by Midvatten AB, which noticed that the iron content in groundwater samples can vary greatly over small distances. The purpose of this study was to geochemically and geohydrologically determine the factors that influence the content of iron and manganese in groundwater from a selection of eskers in Dalarna, and determine how to best sample groundwater with the method used by Midvatten AB. An evaluation was made of how the vertical variation in soil material, water composition, pumping time and pipe material affects the content of iron in groundwater. Piper diagrams were used to study the relationship between the chemical composition of the groundwater and the content of iron and manganese in groundwater samples from the studied areas. The groundwater from the studied areas was then classified in the Piper diagrams, according to the content of the major ions.

Koldioxidutsläpp vid vägbyggnad - en fallstudie med jämförelse av alternativa byggnadssätt

Abstract This degree project examines how much carbon dioxide that emits during the construction phase of a road project. This is to make it possible to compare how the amount of carbon dioxide differentiates between traditional road construction and Swepave construction, which is PEAB?s alternative way to design roads. To make the comparison a calculation tool has been produced. To compare the amount of carbon dioxide emissions a reference project was needed.

Isolerande balkonginfästningar : Thermally-insulated balconies

In this work a study has been performed to show the different kinds of insulated balcony connections exists on the market. In the work there is also a short description of thermal bridges concerning balconies. A description of older solutions for balcony connections is given as well as a calculation of the difference in energy costs for a insulated balcony connection compared to the standard connection. The work includes a short description of the different products. After that there is a short information about their insulation properties, durability, acoustic performance, assembly, computer programme and a short analyses for each product..

Döden till mötes : kriterier för att lokalisera avrättningsplatser på Gotland

The aim of this thesis is to investigate which criteria that can be used to locate execution sites on the island of Gotland, Sweden. The execution sites, which are used to test the criteria against, range in date from early medieval period to 1876 when the last public execution in Sweden took place. Why these criteria can be used will be discussed along with attempts to explain why they have been used frequently or not so frequent. The results show that the execution sites are most commonly located in clear view, near roads, on heights and on unfertile soil. Other criteria that appears less frequent, but that still can be used in the process of locating execution sites, are graves, crossroads and boarders..

Opportunities for improved environmental sustainability of a wine producer in South Africa : natural resource management and climate change adaptation and mitigation

South Africa has been among the top ten wine producing countries for at least 20 years. Even though the land under grapevines is decreasing globally it is still increasing in Africa. The awareness of environment has strengthen the last years and South African producers experience a high demand of environmentally friendly produced wine, especially from the European market. This demand was the driving force behind the development of the world unique sustainability certification, Integrated Production of Wine (IPW), which is inscribed in the South African legislation. What makes this certification unique is that consumers can trace their product all the way back to the farming practices owing to the identity number specified on the IPW Integrity & Sustainability seal on certified products.

Lyftanordning för kraftuttag

This thesis has been developed inassociation with Strängbetong AB, Sweden.A few years backCementa AB introduced a new type of cement on the Swedish market: Byggcement,which is a Portland Limestone Cement. This type of cement is better for theenvironment and cheaper than Rapid Hardening Cement which is used today at SträngbetongAB.Strängbetong AB isvery interested in a change of cement in the factory and wants to know what ittakes to make a transition from Rapid Hardening Cement to Byggcement.This final projectaims at investigating how the workability and strength development are affectedby a transition from the existing cement to Byggcement and how we can change theproperties of the concrete by adding different types of superplasticizers. Laboratory and factoryexperiments were made, to investigate the transition..

Nitrogen flow in Scania : substance flow analysis on a regional level

In this thesis, the flows of reactive nitrogen (Nr) in Scania were investigated and quantified. The thesis was also intended to form a basis for comparison between the urban nitrogen flow and other flows of nitrogen within Scania. The management of nitrogen in society has disturbed the natural nitrogen cycle. This is linked to a series of environmental problems such as eutrophication, acidification, global warming and smog. The method used was Substance Flow Analysis (SFA) for Nr. For calculation and flow charts Scania was divided into three subsystems; air, water and society.

De talar av erfarenhet : uppfattningar om begreppen demokrati och diktatur hos vuxenelever med utländsk bakgrund

I have in this study examined, through qualitative interviews, how adults with foreign background that are pupils in adult education in Sweden, understand the concepts democracy and dictatorship. Their expressed understandings have been compared with their former life experiences as well as with the aim of the social studies to create a qualitative understanding of essential social concepts. My starting point is theories about the adult in leaning processes. It has been assumed that the adult interprets the world much through former life experiences. I have also relied on the idea that having a qualitative, more scientific, understanding of essential subjects is important for the adult as a member of society and participator in the on-going political debate.

Tidsstudier i kalvuppfödning :

Swedish agriculture stands in front of big changes the whole time. As a milking producer you have to adapt and develop the company to these changes and find the best solution. This potential is easy to find if you compare your company with other similar companies. Labour cost is the biggest cost in milking production after the cost for food. Today it is rather easy to measure how many hours per cow different system of cow houses needs, but we do not know so much about how many hours it takes to breed a calf. To learn more about the labour time with the calves during the first time after the calf was born, I made time studies on five different farms with calf hutches, automatic milk system, large calf boxes, and smaller calf boxes with teat buckets.

Trafikklasser för markplattor av natursten : förslag till klassificeringstabell

This report deals with hard surfaces and the factors which are behind the criteria for dimensioning, also dependent on the level, or volume, of traffic. A test was made on slabs of two kinds of natural stone. This was made to see if the values that were reached for breakload was transferable to the same tables that the concrete industry is using for surface dimensions of slabs and paving stones. The test showed very high values and the result, together with the written study, led to the author?s suggestion for a classification table where slabs of natural stone were divided in to different classes depending on traffic, thickness and durability..

Optimering av betong med Byggcement (CEM II) till håldäcksproduktion

This thesis has been developed inassociation with Strängbetong AB, Sweden.A few years backCementa AB introduced a new type of cement on the Swedish market: Byggcement,which is a Portland Limestone Cement. This type of cement is better for theenvironment and cheaper than Rapid Hardening Cement which is used today at SträngbetongAB.Strängbetong AB isvery interested in a change of cement in the factory and wants to know what ittakes to make a transition from Rapid Hardening Cement to Byggcement.This final projectaims at investigating how the workability and strength development are affectedby a transition from the existing cement to Byggcement and how we can change theproperties of the concrete by adding different types of superplasticizers. Laboratory and factoryexperiments were made, to investigate the transition..

Växter och jord i urban miljö : en fallstudie vid Västergatan i Eslöv

Detta arbete består av två delar. En litteraturstudie med stort fokus på jorden och en praktisk undersökning av trädraden vid Västergatan i Eslöv där vegetationen består av Acer platanoides och Stephanandra incisa 'Crispa'. Litteraturstudien omfattar: ? egenskaper man kan förvänta sig i en urban jord ? markpackningens betydelse för jordens vattenhållande förmåga samt för växterna ? vikten av lufttillgång för växternas rötter ? hur markporförekomsten påverkar dräneringsförhållandena i jorden ? kort om pH och näringsämnen ? hur vägsaltning påverkar marken och växterna ? vikten av etableringsskötsel, åtgärder vid slitage/sabotage ? kort om ohyra och rotskador vid anläggningsarbete Fallstudien omfattar: ? undersökning av träden genom ? omkretsmätning av samtliga träd på den aktuella sträckan ? årsringsmätning med hjälp av borrkärnsprover hos fem slumpmässigt valda träd ? okulär analys ? undersökning av marken genom ? enkla jordanalyser med hjälp av agronomkäpp ? att känna på marken med penetrometerkäpp ? analys av en 94 cm djup provgrop, med dess fyra horisonter ? bedömning av rotförekomst I min undersökning har träden varit svåra att analysera, eftersom de saknat bladmassa och grenverket sitter mycket högt. Jag tog borrkärnsprover ur veden för att bedöma årsringstillväxten, men dessa är för få för att jag ska kunna dra några pålitliga slutsatser ur dem och jag har enbart hittat borrkärnemätning på en lönn i litteraturen. Min slutsats är att marken är kompakterad till kraftigt kompakterad, beroende på djup.

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