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1000 Uppsatser om Moisture; Solid wood; Vapour barrier - Sida 4 av 67

Stubbtransporter och bränslekvalitet hos stubbved :

Stump wood is a hot alternative when the heating plants demands more and more forest fuel. The aim with the study has bean to calculate the costs in four different systems for transportations of stump wood, examine if there are any differences in fuel quality for the stump wood in the different systems, analyse if the fuel quality in stump wood is affected with the time it lays by the road side and how much space the stump wood demands on the road side. To calculate the costs for the different systems a system analysis was carried out, where some of the costs were collected through field studies on Holmen Skog stump experiment and other costs were collected from literature and contacts. Data for the fuel quality study was collected from Eons heat plant in Norrköping. Data for the study of how much space stump wood takes along a roadside was collected from field studies.

Fältmätningar av limträbalkars elasticitetsmoduler : utvärdering av tre mätmetoder

This study investigates three different methods for evaluating MOE,Modulus of Elasticity, in field measurements. The purpose is toinvestigate the possibility to use dynamic measurement methods infield measurements that hitherto (2010) has been performed with staticmethods. The objects of investigation are 20 glulam beams. The firstfield measurement took place in november 2007 and applied a staticmethod based on the standard SS-EN 408. The second measurement,described in this study, took place during summer 2010, and appliedstatic as well as dynamic methods.The MOE of wood is affected by a range different factors.

Utformning av sidoområden med hänsyn till vägens livscykelkostnad

Single vehicle accidents are one of the most common types of accidents that occur on the Swedish road network. Depending on the design of the road, the presence of a crash barrier and embankment on the roadside, the outcome of a roadside collision can lead to serious injuries and even deaths.The aim of this project is to investigate the possibility of improving road safety by designing the optimal roadside area based on the results of a life cycle cost analysis (LCC).The questions that have been answered during the duration of this project are:1) Describe the current technical solutions for roadside area design and the various barrier types used in Sweden.2) Complete an existing mathematical model that has been developed by Hawzheen Karim, for calculating life-cycle costs for various roadside areas.3) Calculate and compare the life cycle costs for the side area with a barrier and without a barrier.By performing an analysis of the documentation on the current guidelines and rules for shaping the roadside, was it possible to describe the current technical solutions for the formation the roadside as well as the current roadside barriers in use today. A mathematical model for calculating the life cycle costs of different barrier types had already been developed by Hawzheen Karim. This model was supplemented so that it could calculate life-cycle costs of the roadside region with and without a barrier. After the model was completed, an analysis was performed to obtain life-cycle costs of a roadside with and without a barrier.The result showed that there is a clear relationship between the slope inclination, fill height, and the rate at which the costs rise.

Droppbevattningens inverkan på kvalitet och kvantitet hos Solanum tuberosum L i jämförelse med konventionell spridarebevattning :

A literature study and a field trial have been carried out in order to investigate the physiological response of potato plants to different soil moisture levels. Higher yield, quality and number of tubers can according to the literature be obtained if constant high soil moisture is kept during major parts of the growing season. A field trial was set up where drip irrigation was used as an alternative to conventional irrigation techniques to maintain high and constant soil moisture. The application of water in the drip irrigated area was monitored and adjusted on a daily basis so that the soil moisture stayed as close as possible to the recommended level. The sprinkle irrigated area was irrigated according to traditional practices with approximately 35 mm every 7th to 10th day depending on the whether.

Elementkoncentrationer i gran utmed en markfuktighetsgradient :

One key factor in silviculture today is sustainability. In order to achieve sustainability it may be important to restore lost nutrients to the forest after clearcutting. In order to calculate the removal, you need to know how much of different elements you will find in different tree compartments. The aim of this study was to investigate if the concentration of elements in different tree compartments of spruce (Picea abies (L.) Karst) were related to the moisture conditions of the site. Five plots at Risfallet (60º 21´ N, 16º 13´ E), was placed along a moisture gradient in a 40- year spruce stand.

Sveaskogs möjligheter att utveckla trädbränsleverksamheten i Västerbotten och södra Norrland :

This final thesis is initiated by the wood fuel department at the Swedish forest company Sveaskog as part of a project which also involves two other final thesises. The overall goal of the project is to investigate Sveaskog´s possibilities to produce and sell different wood fuel assortments in Västerbotten and the southern parts of Norrland. The aim of this thesis is to investigate how much wood fuel Sveaskog can produce in the area during the next five years and what that would cost. Furthermore the thesis will investigate the total possible supply of wood fuel from all other possible producers in the area. Treated assortments are forest residues from final fellings, whole trees from direct wood fuel thinnings, non industrial wood and industrial by-products from sawmills. The main effort to investigate Sveaskog´s production possibilities has been made to calculate the possible annual amount of forest residues and fuel from wood fuel thinnings that can be produced.

Qualities and supply of suitable dead wood for Ceruchus chrysomelinus and its dispersal pattern in a translocated population

The wood-living beetle Ceruchus chrysomelinus is a rare species connected to natural forests. In Sweden, it is red-listed as endangered (EN) and an action plan for its preservation has been done by the Swedish Environmental Protection Agency. In this work I have therefore investigated how a translocation of the species succeeded after 17 years. I aimed to study the species dispersal biology, its substrate preferences and the supply of suitable wood on this site. The study was performed during 2012 in Pansaruddens nature reserve close to Uppsala in Sweden, which is a spruce dominated forest.

Hör träbränslena hemma i växthusen? :

With the elevated oil prices of today it is necessary to look for other heating alternatives. If the oil price continues to develop in the same way it has done the last years it will soon be impossible for many producing garden companies to survive. The purpose of this diploma work is to compare three different fuel options in order to find the most economic one considering the conditions of Katrinebergs Handelsträdgård AB. In relation to oil it is profitable to change to any of the three alternatives: wood chips, wood pellets and grain. The most profitable option is to change to wood chips. This alternative has a payoff time less than three years and after that the annual saving compared to the oil is relatively high. The annual cost is 65 % of the cost of the oil alternative.

En jämförande studie av fem lastbilsmonterade flishuggar

The study was carried out as a time study of five wood chippers placed on trucks,so?called huggbilar. They are trucks with built?in wood chipper, chip bowl and crane pulling a chip trailer. The system is used for chipping wood fuel, transporting, and delivering the chips to heating plants.

Bokhögstubbar i Klåveröds strövområde : utbredning, egenskaper och betydelse för rödlistade vedlevande skalbaggar

Lack of dead wood is the main cause of decaying or loss of populations for many forest species. To increase the amount of dead wood is a prerequisite to maintain biodiversity in forests of northern Europe. In summer 2006 the recreation area Klåveröd, at Söderåsen in Skåne, Sweden, has been inventoried for high stumps (snags) of beech, (Fagus sylvatica). The result of the inventory has been compared with data of the real estate and forest management directories from the owner, region Skåne. The results have also been matched with the results from an inventory of saproxylic beetles in 2005, performed with windowtraps on selected snags both in the area and the adjacent national park Söderåsen. 594 snags were found on 747 ha.

Förbränning av pellets framställda av defibrerad granråvara :

Fuel pellets are in Sweden mainly produced from sawdust and cutter shavings. Before the pelletising process the raw material is dried to attain consistent moisture content and ground up in a hammer mill. In the densification process (pelletising) the ground material is forced through holes in a rotating die. This heats up the wood particles which cause them to soften and self bond. After the process the pellets are cooled, sieved and bagged. The milling process creates a wide range of particle sizes.

Isolera bakterien, inte patienten! En litteraturstudie om MRSA-bärarares upplevelser av isolerings- och barriärvård.

The purpose of the study is to investigate MRSA-positive individual´s perceptions of source isolation and barrier nursing, to find nursing inventions witch can provide these patients wellbeing. Eight scientific research reports have been examined, using the guiding principles of Polit et al (2001). The result of the study shows the patients experiences of mentally health/illness, information and communication, physical restrictions and barrier nursing..

Automatisering av spraytorkningsprocess

ABB Surge Arrestors in Ludvika have for a long time had a problem to keep the moisture at a steady state in the production of their ZnO-powder, that is used to produce varistors.Some black-box models of the spray drying process have been designed and evaluated to find a solution for the problem. After evaluating the collected data it has been found that variations in the supply voltage causes control difficulties for the operator. A cascade control system was designed, consisting of three PI control loops designed with lambda tuning. The disturbance in the supply voltagewas used as a feed forward in the control system.At the end of the project the control system was installed, and tests were made to verify the functionality of the regulator. It was shown that most of the variations in the moisture of the powder could be eliminated using small resources, through purchase of a process controller and four power meters.

Produktivitet och lönsamhet vid skörd av skogsbränsle i klen björkgallring :

The aim of the study was to compare productivity in first thinning of birch stands, when either energy- or pulpwood was harvested. The systems total profitability was also compared by including forwarding and chipping costs. A Gremo 950 HPVR harvester was used and the same driver was used under the entire study. During the pulpwood harvest a Logmax 4000b harvester head was used and a feller buncher head made by Silvatec was used during the energy wood harvest. Six study unit pairs were located in a birch dominated stand outside Ängelholm in Skåne.

Uppfattningar om tryckved bland träbearbetande företag i Sverige :

The primary purpose of this study has been to investigate the Swedish timber industry?s perception of compression wood. A secondary aim has been to describe particular areas within the production process where compression wood is likely to cause problems. This study has mainly been carried out as a questionnaire. In order to connect the findings to current research, additional information has also been collected by means of a literature review. The questionnaire has been intended for sawmills and wood-manufacturing companies from various production classes and owner categories, as well as from different parts of the country.

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