Sökresultat:
1020 Uppsatser om Soil parameters - Sida 53 av 68
Skilda världar ? Herrklubben kontra föredömet : En studie om rekryteringsprocessen till bolagsstyrelser i börsbolag och statligt helägda bolag
Background: Female representation on boards is an ongoing debate. The European Parliament voted in November 2013 in favour of a proposal that it should be at least 40 percent women on company boards by 2020. Jens Spendrup, president of the Confederation of Swedish Enterprise, was interviewed on Swedish Radio in February 2014 and stated that there are not enough qualified women to recruit to the company boards. The listed companies in Sweden only have 22 percent of women in their company boards and given Jens Spendrup?s statement should they have difficulty reaching up to 40 percent by 2020.
Förstudie till våtmark i Rimbo : Design för optimal hydrologi och kväverening
The euthropthication of the Baltic Sea is a threat that is beginning to be taken seriously by the governments concerned. In Sweden, regulations concerning the allowed nitrogen (N) concentration in the effluent water from wastewater treatment plants are being tightened up. The Rimbo wastewater treatment plant has been imposed to reduce the annual mean concentration of total N in the effluent water to levels below 15 mg l-1. A more and more common way to reduce the nitrogen level in wastewater is to let the water pass through a wetland. This study investigates the possibility to build this kind of wetland at the outlet of the Rimbo wastewater treatment plant.A prestudy of the topography, soil characteristics and groundwater flow indicates that the land area in question is well suited for the construction of a wetland.
Kaliumgödsling på torvmark - effekt på tillväxten hos planterade granar (Picea abies)
Peat lands are a great potential resource for increased forest growth in Sweden, there are approximately 6.5 million hectares of peat lands, whereof around 70% produce less wood than one m3sk/ha and year and are therefore classed as forest waste land. There are over 200 000 hectares of peat land that is already drained and wooded, and that may be suitable for fertilization. Forest production on peat soils usually requires drainage and fertilization. Dewatering requires ditching the area, so that the roots can have access to oxygen. Nitrogen is often abundant in the peat but other nutrients; especially potassium is in short supply. The purpose of this work was to examine the effects of potassium fertilization on the growth of spruces that were planted on drained peat land and how different amount of fertilizers affects the growth. Potassium deficiency is strongly growth inhibiting, since potassium is important for substance transport in the tree. Potassium is also important for the carbohydrate formation, and because increasing the sugar content of the cells constitutes a lower freezing temperature does potassium availability in the soil play a major role in the winter resistance of many species. Potassium is not found in any organic compounds in the tree, but is present in cell and tissue fluids. A fertilization trial was started in 1978 in Siljansfors Experimental Forest. The plots in the experiment were fertilized with different amounts of potassium and one plot was left without fertilization. All plots that were fertilized with potassium grew considerably better than the unfertilized plot. The difference in production between the unfertilized plot and the plot that received the most potassium was 7.2 m3sk/ha and year. The unfertilized plot can still be classified as waste land. The theoretical production capacity was estimated using a Swedish system for site quality estimation of wetlands after ditching (dikningsbonitering). The plot with most potassium produced after fertilizationaproximately in level with theoretical estimations. Key words: Peat land, Fertilization, Ditching, Growth, site quality..
Kombinerat system för ventilation och rumsuppvärmning : Parameterundersökning i simuleringsmodell för takvärmesystem
A large amount of our time is spent indoors in an artificial climate. To make the experience pleasant there are requirements on the ventilation and the heating system. At the present time the most common form of heating is a radiator system complemented with a ventilation system. A ceiling heating system with combined heating and ventilation can replace the two separated systems. The benefit with a ceiling heating solution is that it saves space since the radiator system is no longer needed.
Vattenvård vid slutavverkning : före och efter vattenvårdsutbildning på Stora Enso Skog, distrikt Siljan
In 2006, Stora Enso Skog implemented an education program in water management for
harvester operators, timber purchasers, cut block planners and supervisors. The focus of the
program was creating stream crossings with minimal harm to the stream and the surrounding
riparian area. This main purpose of this study was to determine the difference in work
procedures before and after participating in the program. The methodology consisted of field
studies and interviews with harvester operators and their supervisors.
The field study looked at how the streams had been crossed concerning the number of
crossings, visible damage to the stream and/or the riparian area made by the machines.
Biological parameters such as the width and dept of the stream and amount of large woody
debris in the stream were also measured.
The field result from 30 harvesting sites showed no significant difference between sites that
had been harvested before or after the education program. But the harvester operators and
their supervisors experienced an increased concern for watersheds after the educational
program.
Är korta spenar ett problem i samband med mjölkning? :
In some herds it has been observed that extremely short teats have become a problem; with a negative influence on the milking performance. The aim of this study was therefore to investigate to what degree the quality of the teats and the milk in cows with short teats is affected as compared with cows with normal teat length and furthermore if the milking performance could be improved by using a liner adapted to short teats.
This study was divided in two parts. In the first part, it was examined if there were any differences between short teats and teats with normal length with reference to the milking performance, udder emptying, teat treatment, milk quality, and udder health. 11 pairs of cows were used and in each pair of cows one cow had teats shorter than 40 mm while the other cow had teats longer than 50 mm.
Hårdhetsvariation i grundvatten längs Badelundaåsen mellan Leksand och Avesta
Water hardness indicates the concentration of calcium and magnesium ions in water. Water with high concentrations of these ions is described as hard water and water with low concentrations is described as soft water. Water that is too hard or too soft can lead to technical and economical problems. In collaboration with Midvatten AB, groundwater hardness in the Badelunda esker between Leksand and Avesta has been mapped, and an attempt has been made to explain the variations. For this purpose, different GIS programs, such as ArcView, ArcInfo, IDIRISI, and one geochemical modelling program, PHREEQC, has been used.
En intervju och enkätstudie av besökare i tre tätortsnära skogsområden i Stockholmstrakten :
This Masters thesis is made as the first of two visitor surveys of three urban forest
areas. These areas are; Skutan recreational area in Haninge, Ugglevikskällan on Norra
Djurgården in Stockholm and the Paradiset Reserve in Huddinge. The study is made
in cooperation with the managers of the three areas operating within the European
Union Life Project regarding Urban Woods for People.
The goal has been to collect data through studies of visitors and close by residents in
the three areas. The results are to be used as primary values for the follow-up as well
as a basis for managerial decisions. The interviews and surveys are also constructed in
a fashion so that they can be used for the follow-up study.
For the Skutan recreational area the mode of contact was by sending forms to the
nearby residential areas.
I vatten eller jord? : Nytolkning av depåfyndet från Eskelhem
In 1886 Hans Hildebrand received a Bronze Age hoard found in a field that belonged to Eskelhem´s rectory. A record was made where Hildebrand presented and documented the artifacts. The following year Oscar Montelius reviewed the artifacts, which he described as horse gears. He compared the horse gears with similar artifacts found in Europe that roughly had the same dating in order to trace the origin of the hoard. Montelius conclusion was that the hoard was created on Gotland around 500 BC.
Optimering av smidesgeometri för P-fläns på bakre turbinstativ (TEC)
This thesis work has been performed at Volvo Aero Corporation in Trollhättan, at the department of ?hot structures? involving aircraft engine GP7000. The purpose with the study was to investigate the possibility to reduce size of the forging of flanges on the rear turbine frame when purchasing. Thereto examine the parameters that affect the flanges motion during the manufacturing process. The goal was to provide Volvo Aero with foundation to later bring in slimmed forgings.
Det förbryllande sambandet mellan risk och avkastning : En studie av de nordiska finansiella marknaderna
Purpose: The purpose of the study is to in a comparative and causal way explore whether there is a relationship between risk and return and also how it is perceived on the Nordic financial markets.Theory: The theoretical frame of reference applied in the thesis is considered relevant inthe perspective of the study?s purpose and research questions. We have among other theories used The Capital Asset Pricing Model, The Efficient Market Hypothesis and various Behavioural finance theories.Method: The study has its starting point in a quantitative approach with a quantitative data analysis supported by secondary data extracted from Thomson Reuters.Empirics: The empirics contains regression analyses made from calculated secondary data of 240 randomly chosen companies from Nasdaq OMX Stockholm, NasdaqOMX Copenhagen, Nasdaq OMX Helsinki and Oslo Bors.Conclusion: The study conclusions show that there are both a negative and positive relationship between volatility and actual return on the investigated markets. Considering this prior statement we can conclude that the Capital Asset Pricing Model can?t correctly describe the actual relationship between the parameters investigated on the current sample.
Styrsystem : För en forskningsutrustning
The division of Engineering Materials at Linköping University, department of Management and Engineering, conducted a research project concerning Fatigue life of thermal barrier coatings during 2009. During this project equipment to provoke these fatigue failure by rapidly heating and cooling test subjects in cycles, was ordered.Design and manufacturing of the equipment was handled internally at LIU.The equipment was built using a furnace that is lowered and raised over the table where the test subject is placed. To keep the temperature of the furnace a lid slides in place to close the downward facing opening of the furnace when it is in the raised position. On this door there is nozzle that is used to cooling of the test subject by air.To make sure that the equipment can work independently you need an automation controller that can evaluate if movement can occur without danger of collisions. The control system also needs to monitor that all elements are performed according to plan.This degree project is based on a modular system from OPTO 22 and includes the configuration of a PLC that will be supplied with logic and a user interface.The degree project resulted in a graphic interface in which a user can set desired values for different parameters and get information about current values for them.
Analys av off-design prestanda för ett absorptionskylsystem
This master thesis project at KTH is performed in the Mechanical and Aerospace Engineeringdepartment at University of Florida (UF). The thesis is a small part of a gas turbine researchproject where a vapour absorption refrigeration system (VARS) and a high pressure regenerativeturbine engine (HPRTE) are integrated together. The main objective is to build a computermodel of the VARS. The computer model is supposed to be used to analyse the off-designperformance of the VARS and should also be easy to integrate as a subroutine in a more complexsystem model. To model the VARS some knowledge of the absorbent/refrigerant mixture had tobe well known, in this case a mixture of ammonia and water.
Effekt av brand och bete p? uppkomst av ?rtartade v?xter i restaurerade betesmarker. En j?mf?rande studie
Open ecosystems, such as grasslands and pastures, have naturally been shaped by disturbances like fire and grazing. These processes play a crucial role in creating habitats with high biological diversity, particularly favourable for a wide range of herbaceous plant species. In recent years, many of these disturbances have ceased, leading to encroachment, fragmentation and habitat loss. The aim of this study was to examine and compare the effects of fire, herbivory and a combination of fire and herbivory on the emergence of herbaceous plants. The study was conducted at the Ecopark at Nordens Ark.
Grafisk utvecklingsplattform för signalbehandling - Design och implementation
We have different kinds of signal processing everywhere around us in our everyday life, in our cellphones, when we are listening to music, watching TV etc. This makes signal processing a very interesting and important technical area, where the demand of skilled engineers sets the limit of what is possible.Working with signal processing requires in-depth knowledge in areas such as mathematics, physics, electronics, and other related areas. For this, it has traditionally been demanded by a talented developer to also master the advanced programming languages such as C / C + + and Assembler.This has begun to change; today there are several companies that offer graphical development environments for signal processing, environments where programming skills are not needed anymore, and the focus can be on signal processing instead.The goal with this project is to build a corresponding graphical development environment to reach an understanding of what is required of these systems, and also to grasp what opportunities that are available within graphic programming. Inspiration for the work has partly arise from some of the tools available on the market, and partly from previous theses that have been written about graphic programming.The challenge lies in creating a program that can execute signal diagrams in real time from given signal blocks, and be able to handle feedback loops in an efficient way and to do so at the lowest "cost" in terms of clock cycles as possible. This should also be compared against to code, compile and run a complete signal diagram directly.To increase the usability it should also be possibility to externally manage in real time the parameters of the signal diagram during execution.The interface is a separate program, which is to some extent similar to Matlab Simulink, where a signal diagram is drawn up graphically by connecting wires between different signal blocks.