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491 Uppsatser om Slope calculation - Sida 22 av 33

Effects of biogas residues on respiration and denitrification in arable soil : evaluation of methods, microbial activity and agronomic implications

Agricultural soils constitute the base in human food production and soil content of organic matter and plant nutrients together with soil microbial activity are all important parameters for high crop yield of good quality. These parameters are dependant on proper fertilization.Anaerobic digestion of organic wastes for biogas production generates a liquid residue called biogas residue (BR). It contains organic material and plant nutrients which makes ita potential fertilizer for arable cropping. However, it also contains heavy metals and toxic organic compounds and it is therefore in need of evaluation before usage.Microbial tests were performed aiming to evaluate the agronomic traits of four different BR and to find a viable procedure for evaluating slurry fertilizers. Two experiments where soil respiration and soil potential denitrification activity (PDA) was measured at fertilizer addition were performed.

Byggnadsinvesteringsbedömning : En studie av 44 svenska kommuner 2011

Syfte: Syftet med studien är att undersöka och presentera vilka investeringskriterier som svenska kommuner använde år 2011 vid byggnadsinvesteringar, samt i vilken utsträckning extern hjälp vid investeringsbedömning och utförande av byggnadsinvesteringar användes.Frågeställning: Vilka samband fanns mellan investeringsandel per omsättning och i hur stor utsträckning beslutade byggnadsinvesteringar blev dyrare än beräknat?Vilka skillnader fanns mellan större och mindre kommuner med hänsyn till investeringsbedömningar i byggnader?I vilken utsträckning förekom samarbete mellan kommuner gällande byggnadsinvesteringar?I hur stor utsträckning anlitades extern hjälp med projektledning och kalkylering vid byggnadsprojekt?Metod: Studien är baserad på en webbenkätundersökning med 44 deltagande kommuner och en personlig intervju. Denna undersökning analyserades och jämfördes sedan med en referensram baserad på sekundära källor.Slutsats: Större kommuner behöver förbättra sina planeringar och kontrollera sina byggnadsinvesteringar i och med att investeringarna ofta är större och fler saker kan gå fel än för mindre kommuner.Fler kommuner borde samarbeta mer vid byggnadsinvesteringar för att på det viset kunna matcha byggföretagen vid upphandling.Kommunerna bör fortsätta kontrollera den externa hjälp de använder vid byggnadsinvesteringar och göra tydliga kontrakt..

Miljöpåverkansbedömning vid tillverkning av etanol från cellulosabaserade råvaror : ekologisk gård självförsörjande med drivmedel

Fuel produced from renewable resources is of big interest. In this project the difference between a few different renewable materials are compared on the matter of environmental load when ethanol is produced. The renewable materials that are compared are Salix, straw and reed canary-grass (rörflen). The cellulose in the material is cut down to small pieces and then hydrolysed so that the sugar from the cellulose can be fermented into ethanol. Tha amount of ethanols that is studied in this work is the smount of ethanol needed to cultivate 1000 ha. The functional unit in the report is 1000 ha.

Inventering av värmelager för kraftvärmesystem

When a combined heat and power plant produces heat and power it often faces a deficit of heat load during the summer or other periods of time. This heat is often unnecessarily cooled away or the power production has to be reduced or shut off. If it is possible to store heat from periods with low heat demand to periods with high heat demand one can get many benefits. Among these benefits are: increased power production, decreased operation with partial load, uniformly distributed load.To be able to store heat in situations like this long-term thermal heat storages are needed. In this thesis five different types of stores are presented: rock cavern storage, tank storage, pit water storage, borehole storage and aquifer storage.

Studie av introduktionen av NorFor Plan för foderstatsberäkning till mjölkkor i Sverige :

NorFor is a cooperative project between the consulting organisations owned by the farmers in the Nordic countries ? Sweden, Norway, Denmark and Iceland. The project started in 2001 and the outcome, the system for ration calculation NorFor Plan and the model for evaluating the ration NorFor Evaluation, was completed in 2006. Along with NorFor Plan economical optimization are available and according to literature, the optimization will generate a 2 öre lower feed cost per kg milk, and thereby improve the profit for the farmer. The use of NorFor Plan in Sweden for feed optimization during spring 2008 has been very small. In this study eight herds in the middle of Sweden fed half the herd according to the classical system used in Sweden and the other half according to NorFor Plan system.

En kombinerad Organisk Rankinecykel och värmepump integrerat med ett fjärrvärmesystem : Där värme- och elproduktion samt lönsamhet studeras och avfall är huvudbränslet

The demand for district heating is expected to decrease in the future, due to competition from heat pumps and energy efficiency measures in buildings. Development of existing district heating systems is therefore necessary for district heating companies to maintain market shares. This Master?s thesis describes and investigates the heat and electricity production and profitability of a combined Organic Rankine Cycle (ORC) and heat pump that is integrated with an existing district heating system. The studied district heating system is utilizing heat from waste incineration. In Sweden waste constitute 20 % of the fuel mix used in district heating systems, and this share is expected to increase in the future.

Konstruktion av infästning till dysa

The goal of this thesis is to design an attachment between a duct and a pod. A pod is what could be compared to an outboard engine for larger vessels. The pod is placed on the outside of the ship?s hull and can rotate 360 ?. A duct is a large steel ring that can be placed around the propeller on the pod to increasethe propulsion force of the ship in lower velocities.

Fysikalisk modellering av klimat i entreprenadmaskin

This masters thesis concerns a modeling project performed at Volvo Technology in Gothenburg, Sweden. The main purpose of the project has been to develop a physical model of the climate in construction vehicles that later on can be used in the development of an electronic climate controller. The focus of the work has been on one type of wheel loader and one type of excavator. The temperature inside the compartment has been set equal to the notion climate. With physical theories about air flow and heat transfer in respect, relations between the components in the climate unit and the compartment has been calculated.

Hantering av skadade styrstavar

The thesis was performed at Forsmarks Kraftgrupp AB in the department ofmechanical engineering, FTCM. Forsmark nuclear power plant has had problems with cracks in some of the controlrods which are placed in the reactor at Forsmark 3. To investigate the cause of this,material samples were taken from five of the damaged control rods. This sampling ofthe rods resulted too short rods to be transported in the shipping container to theinterim storage facility for used nuclear fuel in Oskarshamn. Control rods are crucial components in a nuclear reactor, regulating the reactoreffect by blocking or unblocking fuel rods. Control rods which have been in thereactor are always handled under water in order to protect against the radiation theyemit. The task was to design a control rod adapter that extends the control rod sotransport can be performed from Forsmark. The goal of the work was a complete setof blueprints so the control rod adapter can be manufactured and mounted on theshort control rods and then be transported to the interim storage facility. The work began with mapping of how control rods normally being handled from thereactor to the interim storage facility.

Drivkrafter bakom den totala faktorproduktivitetens utveckling på regional nivå : En fallstudie på de svenska FA-regionerna under perioden 1990 ? 2005

Production requires the input of capital and labour. Hence, economic growth can be assumed to follow from increased levels of these two factors. Policies aimed at increasing production may consequently successfully be focused on facilitating the accumulation of capital and labour. However, even when an economy has managed to reach the same quantities of input factors as a more prosperous neighbour, the level of the production might still differ. The explanation of this lies in what economists refers to as expression embracing the characteristics of the input factors and the conditions in which they operate.In this thesis a calculation of total factor productivity is carried out, using existing data on the Swedish FA-regions between 1990 and 2005 and the method the economist Robert Solow in the 1950?s.

Kostnader för jordbearbetning och sådd :

Syftet med detta examensarbete är att sammanställa maskinkostnader för etableringsmetoderna plöjningsfritt och konventionellt. Vi vill även titta på hur stor kapacitet som behövs på maskinparken för den tänkta gården på 600 ha åker, detta för att hinna etablera grödan inom ett rimligt tidsspektra. Anledningen till att vi valt ett företag på 600 ha är att det är den areal tröskan klarar av att avverka inom rimlig tid. Det medför att vi måste ta en del hänsyn till lägligheten och hur mycket av tiden som är så kallat ?tjänligt väder?.

Motiv och avkastningsvärde vid köp av skogsfastigheter : en intervjuundersökning

The purpose of this paper has been to find out what motives buyers of forest property has for there purchasse, what competence they have in economics and forestry, and what analysis they had done before the purchase. The study is based on interviews with nine different buyers from two geographical areas, five from Hälsingland and four from Småland/Skåne. A forest property is a property where the value to 100 % consist of forest. A part from the interviews every purhase has been analysed in comparison to an estimation of the yield value. The theoretical yield value was estimated with a computer programme.

Konstruktion av kostnadseffektiv fläkt till härdningsugnar

Scana-Booforge is a Swedish company which specialize in heat treatment of various metal. The treatments take place in quenching ovens, where fans are used to circulate the hot air. The fans used today do not have a satisfactory lifespan. This thesis aims to develop a new design of the fans for the quenching ovens, and the goal is that the new fans will bring cost savings for Scana-Booforge.The design development process started with mapping out the environment in which the fans operate, and with analysis of the existing fan structure and damages, in order to establish the cause of failure and of short durability. The performance of the fan were also established at this stage.

Vad ?r en funktion?

The concept of function represents a major part of mathematics and becomes more significant in school during high school. Throughout history, it has been a difficult concept to define and may create challenges for contemporary students. This literature study aims to identify students' difficulties with the concept of function, as well as to account for how the definition of a function has evolved historically. The literature study has been conducted through database searches in ERIC, Education Research Complete and MathSciNet via EBSCOhost, as well as through chain searching. The study results in identifying that students' difficulties with the concept of function primarily include the graphical and algebraic forms of representation.

Vilometabolism hos barn och ungdomar med Cerebral Pares : En deskriptiv korrelationsstudie

Background: Cerebral Palsy is usually divided into three subgroups: ataxic, spastic and dyskinetic, where children and adolescents can, because of misestimation in nutrition and energy intake, suffer from weight problems.Aim: To compare calculations with equations with the individual's measured RMR in the subgroups, to see if any equation is more suitable. This could be used as a tool to calculate the resting metabolism at times when it is not possible to perform clinical measurements.Method: The RMR has been measured in 37 children and adolescents aged 3-15 years through indirect respiratory calorimetry. Those values have been compared with calculations from five equations. The results were then analyzed in order to find if any equation is better to apply for calculating resting metabolism for each subgroup.Results: The ataxic group was overestimated by 56.5% of the calculated values. WHO/FAO/UNU?s equation indicates a significantly strong correlation between the measured and calculated values (r=0.85, p<0.05).

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