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1418 Uppsatser om Forest properties - Sida 63 av 95
Energieffektivisering av ventilationssystemet i konsthallen Sandgrund Lars Lerin
Uppsala County has ambitious environmental aims for the planned residential area inÖstra Sala backe. In this thesis different energy sources have been evaluated todetermine which system that would be most favorable given currently availableinformation about the project. Planned energy usage has been divided into tap waterheating, space heating and power. Three base case scenarios were made with districtheating, small scale bio fuel and heat pump. Solar power and solar heating were thensimulated and the production from the two could individually be deducted from theenergy need in the base cases, constituting 9 different scenarios.
Bevarande av hotade epifytiska lavar och vedsvampar i Norrbottens län : rödlistan som verktyg i praktisk naturvård
Många arter påverkas idag negativt av skogsbruket. Detta visar sig dels i ett växande antal arter på den svenska Rödlistan. I Norrbottens län är idag närmare 500 skogslevande arter rödlistade, och dessa är fördelade över flera olika organismgrupper. Det stora antalet rödlistade arter i skog innebär att det är svårt att direkt utifrån Rödlistan utforma effektiva naturvårdsåtgärder samt generell hänsyn inom skogsbruket. Genom att sammanställa och
strukturera information om de rödlistade arternas krav på livsmiljö och hotsituation kan Rödlistan som verktyg utvecklas.
Frekvensreglering i det nordiska kraftsystemet
Svenska Kraftnät is (together with the other transmission system operators of the Nordic power system) responsible for keeping balance between the generated and demanded power in the Nordic power system. Spontaneous load variations and system disturbances, however, lead to power imbalance followed by frequency variations. The frequency deviations can be limited to an acceptable level by the spinning reserve, mainly by hydro power control. But there are also other system properties which have a great influence on the frequency and system stability. The frequency and voltage dependence of the loads have a direct influence on the power balance.
Genernas påverkan på köttkvaliteten
Multiple factors are involved in control of beef sensory quality so great variation can be induced. The perception of meat quality can be affected anywhere in the product chain. Both the environment and the set of genes of the animals have an effect on the final output. A problem facing the beef industry today is the significant variations in meat quality between individual animals, which is reflected in the uneven quality of the meat that reaches the consumer. If the quality of meat in stores varies significantly over time, the consumers? trust may decrease.
Pelletering av tallspån : grundläggande studier
Wood pellets are an upgraded product of residuals from several wood processing industries, for example saw mills and pulp industries. The pellets are produced by pressing the milled and dried sawdust to cylindrical units with a higher density than the initial raw material. Pellets have great benefits compared to the raw material: high energy per volume, good transport and storage properties and homogeneity.
Several parameters collaborate in the whole process, which makes it complex. Wood is a heterogeneous material, chemically and structurally dependent on wood parts, habitat and storage procedures.
Patotyptest av potatiscystnematoden :
There are two species of potato cyst nematode (PCN), the yellow, Globodera rostochiensis, and the white, Globodera pallida. Each of them can appear in different pathotypes. These are separated by testing the nematode ability to multiply on a number of potato cultivars with different resistance properties. The aim of this project was to examine the virulence of Swedish and foreign PCN populations and to compare two test methods. Biotests are today the only available tests used to study virulence.
Möjlig kvittblivning och eftermarknad av ridbaneunderlag - topplager
The aim of this study is to find information about what to do when riding arena footings are worn-out. Especially, the surface layer of riding arena footings is very interesting because of its importance of giving grip in every step for the horse, as well as shock ab-sorption. Generally, surface layers are containing several different parts in order to achieve desirable properties. These different parts can consist of organic material or in-organic material (mostly gravel). Gravel and many other materials in the top-layer are environmental friendly, and therefore, easy to get rid of.
Cisterciensklostrens odlingar i Sverige under medeltiden
The aim of this paperisto find out which plants the Cistercian monks might have cultivated in Sweden during the Middle Ages and which types of plants it would have been practical to grow inside or outside of the Cistercian monastery precinct. Archaeologicaland archaeobotanical studies have been consulted to find out which plants were available in Sweden during the Middle Ages. Examples, mainly from Scandinavia, but also from the continent, are used to show that the monasteries were large institutionsthat had to feed a large number of people and that there would not have been enough space to cultivate everything needed within the monastery precinct.Secondary sources have in the main been used to gather this information, except in the case of the Swedish monastery of Nydala where F-Topo, a database developed by the County Museum of Jönköping,has been used to analyse the amount of land and the types of properties owned by the monastery.The conclusion is that for practical reasons the monks would have cultivated plants that needed to be close at hand, that were rare or delicate, that could not be stored for long periods and that were used in small quantities within the monastery precinct. This would include medicinal plants, herbs for cooking and some vegetables like lettuce, spinach,and similar,that do not keep well. Most other items, grains, cabbages, root vegetables, peas and beans could equally well be cultivated outside the walls.
Processchemaläggare för mångkärniga processorer ? Fördelning av minnesbelastning i NUMA-system
For systems with multicore processors contention for shared resources is a problem that occurs when several memory-intensive processes are executed in parallel within the same memory domain. This contention has a direct influence on the performance of the system and is a complex problem that has been recognized for a long time. An attractive and actively studied way to minimize this problem is by using a process scheduler adapted to allocate processor cores in a way such that contention for shared resources is minimized.With the introduction of multicore NUMA-systems (Non-Uniform Memory Access) the situation has become even more complex. In these systems the access time for processor cores to different memory domains vary depending on factors such as distance and load. Thus, the process scheduler also has to consider where the memory of each process is placed to minimize the distance and balance the load on each memory domain.This report presents a user-level process scheduler for a NUMA-system based on the multicore processor Tilera TILEPro64.
Scenerier i glas - ett projekt om mönstermoduler
The present project was initiated with the aim to create pattern modules for use in public environments. My intention was to let the properties, of the specific materials used, have a marked influence on the realisation of the final form. I also wanted to find a material, which is suitable from the perspective of sustainabilityand possibilities to create modules from it. The work was initiated with a study of some candidate materials and many sketches before I finally made my choice. My decision was clear after a visit to the company Glasfabriken inKalmar.
Sitkagranens potentiella merproduktion jämfört med vanlig gran i Hallands län
Sitka spruce (Picea sitchensis) is not considered to be a native species to Swedish forests. It´s origin is the pacific coast of Northern America, an area that is dominated by a coastal climate which makes it likely to believe that it would be well suited for growing in the south-west of Sweden.
This study aims to investigate the gain in production that can be reached by growing sitka spruce instead of Norway spruce (Picea abies) in the county of Halland. A regression model based on data from forest experiments was produced to explain the gain in production. This model was based on elevation and annual precipitation.
The model was then used to create a map layer in arcGIS that shows the gain of volume in comparison to Norway spruce in percent. An analysis was carried out to find what share of the forestland in Halland county that fell into four different classes of production gain.
Estimation of reindeer lichen biomass by image analysis
During consultation procedures between forest owners and the Sámi, data on, e.g., reindeer lichen biomass on the current site is needed. Hitherto, the existing methods of measuring lichen cover and biomass has been either objective methods such as the Point Intercept method, which is time consuming, or some sort of subjective visual estimation, which is faster but less accurate. However, both these methods are sensitive to different observers and/or to different inventories. This paper addresses the further development and evaluation of a photographical inventory method that uses colour distribution in images to estimate lichen biomass. During the autumn of 2011 six different locations, with different grazing pressure and lichen cover, in Norrbotten county were inventoried using both the Point Intercept method and the photographical method, complemented with collection of biomass samples.
Implementering av en PSS i Trängslets kraftstation
The purpose of this master thesis is to implement and validate a Power System Stabilizer (PSS) to a generator at Trängslet hydropower station in Dalarna, Sweden. Problems with local rotor oscillations can occur at the hydropower station when power is transferred on a new power line (130 kV) from Northern to Southern part of Dalarna. To ensure good operation properties on this power line Fortum Generation AB and Fortum Distribution AB wants to activate a PSS on a generator.There have been investigations in which situations and what equipment that contributes to rotor oscillations. When this is known the PSS is tuned to damp these oscillations by choosing a good set of parameters. The most important parameters for good performance are to choose amount of gain and phase compensation.
Val av liggplats och väderskydd hos dikor vid utedrift vintertid
If you keep cattle in a herd outside all year round on big varying grounds, their possibilityto perform their natural behaviour increases. This way of keeping cattle requires that youprovide them with their other needs, like shelter and a dry and clean resting place.According to the animal welfare authority´s regulations on livestock farming, only animalsthat are suited to stay outside during the cold season are allowed to be kept outside. Theyshould also have access to a shelter or another building that gives them protection from theweather and wind and provides a dry and clean resting place.Research has shown that as long as cattle do not get exposed to precipitation and wind theywill manage low temperature well. Some of the things that will affect how well the animalshandle different climates are the isolation ability of the fur, the animals´ body size and thefeed intake. A dry lying place that is both insulating and moisture absorbent is also of greatimportance.
Förskolebarns möten med biologiämnet i naturmiljö : En observationsstudie med fokus på barnens perspektiv
Syftet med denna studie var att ta reda på hur mycket biologi man kan få in i verksamheten genom att uppmärksamma när ämnet naturligt visar sig hos barnen under utomhusvistelse, i deras egna lekar, upptäckter och utforskande. Bakgrunden till min undersökning är att den svenska förskolan sägs befinna sig i en brytningstid, med större fokus på ämneskunskaper och att läroplanen samtidigt poängterar vikten av att ta tillvara barns perspektiv, frågor och idéer. För att få svar har jag gjort observationer på två olika förskolor/avdelningar. Även enkäter har skickats till de medverkande pedagogerna. Resultatet av mina observationer visar att barnen ofta uppmärksammar olika djur och växter och andra områden inom ämnet biologi när de vistas ute i naturen.