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498 Uppsatser om Load cycles - Sida 10 av 34

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.

Är Sambandet Mellan Utdelningsandel och Framtida Vinsttillväxt Positivt

Common wisdom dictates that because payment of dividends decreases funds available for investment, a high payout ratio is to be associated with low earnings growth. This notion has been challenged in recent years by empirical research that has found a positive relationship between payout ratio and future earnings growth, both on the aggregated market level and the company level in different countries. This study investigated the aforementioned relationship on the Swedish market by statistically analyzing future earnings growth as a function of payout ratio on a large sample of publicly listed companies over the period 1980 to 2011. The results are in line with those found in previous research and indicate that companies with high dividend payout ratio tend to experience strong future earnings growth. The results are robust to the presence of mean reversion, the use of an alternative accounting measure of earnings, non-symmetrical earnings growth cycles and alternative practices for dealing with outliers..

Ur led är tiden: En studie av metoder att korta ledtider inom forskning och utveckling

Product development cycles become shorter and shorter. The time from idea to market has become an important competitive factor. Despite this, methods used for making the product development process faster are surrounded with uncertainty about their efficiency. The purpose of the thesis is to describe the pros and cons of ?best practice? methods for shortening lead times and how these methods effect the lead times in research and development.

Avspecialisering som framgångskoncept för jämnare arbetsfördelning?

The application of the LSS law and how the public organization (Municipality of Hudiksvall) later had to reform their organization to fit the new demands is the foundation to this master's thesis. An internal evaluation was performed due to this reorganisation process within the social care department (LSS unit). The aim was to investigate and evaluate if the reorganization resulted in a better working environment and if the work load (distribution of work) became more evenly divided between the different unit managing directors. The primary empirical information to this master's thesis is collected from that evaluation report. The main aim of this master?s thesis is to answer if the organisational choice between specialised or de-specialised working tasks has an effect (experienced and measured) on the level of stress among the unit managing directors.

Kylapotentialen i Drefviken för Vattenfall Heat AB

Vattenfall Heat AB is a district heat provider in Drefviken, but has yet to establish any cooling systems in this area. This thesis examines the potential client base within the area today and over the coming 20 years. The feasibility of the most common cooling technologies is evaluated and results show a total potential for an installed capacity of 30 MW providing 50 GWh of cooling per year. One of the examined areas shows good prospect for heat driven absorption chillers during the summer months when the heat load is limited..

Effekt på östralcykeln hos ston tillförda GnRH-analogen deslorelin (Ovuplant) :

This article starts with a review of the literature regarding the normal reproductive physiology of the mare, prolonged luteal phase and medical drugs used within reproduction of the horse, with emphasis on Ovuplant®. The purpose of this article was to measure the progesterone level in blood, of mares implanted with deslorelin acetate (Ovuplant®). The study was performed at the Department of Clinical Sciences, SLU, in Uppsala. There were seven mares included in the study. They were divided into two groups, one experimental group (four mares) and one control group (three mares).

Näringsretention i återskapad våtmark på betesmark : studier av en mad vid Bornsjön

It is important to construct or recreate different types of wetlands and study their retention of nutrients, since knowledge of their effectiveness in this matter is poor. In 2003 a wetland was constructed on an old meadow on the western shore of Lake Bornsjön in central Sweden. The main purpose of the wetland was to reduce the amount of phosphorus entering the lake, which is the back-up water supply for Stockholm when the city cannot obtain water from Lake Mälaren. Large areas around Lake Bornsjön consist of agricultural land and the nutrient concentrations in the inflows to the lake are usually relatively high (approx. 1 mg/l total nitrogen and 0.05-0.1 mg/l total phosphorus).

Elasticitetsmodulen i en kalkstabiliserad vägterrass : en fältstudie

Stabilization of subgrade is an internationally common technique to improve the characteristics of a soft soil. Improving the stiffness and bearing capacity of the subgrade enables the pavement to be designed with reduced depths of subbase and basecourse aggregates. This makes the stabilization technique both economically and environmentally interesting. Both natural and stabilized soils have high inherent property variability that should be considered when the characteristic value is derived. By analyzing the spatial variability in stabilized and natural subgrades it is possible get the parameters needed for reliability?based modeling of soil properties.

Optimering av indunstningsprocess

The wastewater treatment plant at GE Healthcare's facility in Uppsala deployed a three step vacuum evaporator in 2007. The purpose of this was to pre-treat wastewater containing amines. The purpose of this thesis was to optimize thisprocess by reducing the amount of concentrate without releasing more nitrogen tothe environment and to examine if density could be used as a measurement of whenthe process should be ended.To create a foundation for optimization six test cycles were conducted with samples taken from all three steps. Both concentrate and condensate were tested as well as the incoming solution. Furthermore, the thesis has been expanded with a benchmarking part examining two different evaporators.

Metodik för utmattningsberäkning av svets i vibrationsmiljö

In this work, a method was developed and evaluated for calculating the life of welds under the influence of fatigue loads from a vibration environment. Typically, a shaker table is used for testing a component against vibration loads. The shaker table creates a vibration environment that is defined in the frequency domain by a power spectrum.Similarly, a virtual vibration table can be used to calculate the same type of load environment, which can then be used to calculate the expected lifetime. The benefit of this method is that it can be used in design, as well as in simulation of tests before physical verification tests are carried out.Today there are methods for calculating fatigue life of non-welded base material, but since many components contain welded joints, there is a need to apply this method to those types as well. To achieve this, the thesis combines two different areas, which together provide a method for fatigue assessment of welds using a virtual shaker table.The methodology is carried out by modeling the component, and its welded joints, in a finite element program.

Sol, jord och vatten. : Barns tankar om den ekologiska processen

Studies show that the interest and knowledge about science among teenagers is decreasing. They also reveal the difficulties to explain the ecological processes and that the ideas about the nature are collected from everyday life and early school years.The intention of this investigation was to find out more about children?s ideas and knowledge about the ecological processes and to compare these results with the curriculum.The method was a questionnaire and interviews with children in school year 1 ? 6. The aim of the studies was also to find out if any progress connected to age could be found, concerning understanding of the ecological processes.The results showed difficulties in achieving the predestined goals for biology and chemistry concerning ecology cycles and they differed a lot between the children. Often the learning process showed very little progress.

Självgående fordon hos Sandvik do Brasil

At the plant of Sandvik do Brasil in São Paulo there is a need for improving the transport of inserts between the plant building and the stock building. The idea is to install a system with an Automated Guided Vehicle (AGV) to take care of this transportation. The purpose of this report is to present which demands there are on the system and to find the best solution according to the demands.To conclude this work a study was made of the plant and the AGV technology was examined. Several providers of AGV solutions were contacted to get information about prices and detailed solutions.The conclusion was that the most suitable system for this application is a small unit load vehicle using inductive wire as guiding system..

Lastfördelning och effektmätning med Arduino och PLC

Detta arbete var beställt av Sjöfartshögskolan i Kalmar. Skolan ville ha en enhet som kunde mäta aktiv-, reaktiv- och skenbar effekt, ström, spänning, frekvens och cos? på en generator och som kommunicerade vidare dessa värden till en PLC. Detta för att kunna lastfördela lasten mellan ett antal generatorer i kursen Tillämpad elteknik 15 hp där studenterna bygger en generatorinstallation med tre generatorer. Ett funktionsblock för lastfördelning skulle också programmeras.

Lågoffsetkomparator

Detecting small signals with a comparator demands that the total voltage offset is lower than the actual signal. The total offset includes the voltage offset in the comparator and the voltage offset that is created by the offset currents that flows thru the load at the comparators input. The goal with this comparator that has been developed has been that it will have a total voltage offset at maximum 500 uV. The comparator does not need to be extremely fast or does not need to operate in a big frequency area. To have all the flexibility that is needed a full custom technique is used.

GIS och statistik vid dräneringsområdesvis kväveläckagebeskrivning i Halland

The last decades have shown increased nitrogen leeching from soil to water recipients. This is inSweden mainly due to over-manuring of agriculture land, effectivization of drainage systems and thedeclining extent of wetlands. The accumulated amount of nitrogen in water doesn?t only make itunsuitable for use by humans and cattle, but also decreases the biological diversity as well as negativelyaffect tourism and fish industry. In the most severe cases shallow maritime grounds can be completelydepleted of oxygen due to decomposition of the increased amount algae and plankton growth.This study have the aim to describe and quantify the nitrogen leeching from the Genevad drainagebasin, located in southern Halland, Sweden.

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