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503 Uppsatser om Wood chip - Sida 10 av 34

Datering av röta i hålekar :

I have chosen in this work to examine which factors are affecting the artificially creation of a tree cavity containing decomposed wood. The purpose of the work is to find out which factors are affecting the most when a tree cavity is created, and to apply these results when you artificially try to create a tree cavity. The need to create tree cavities comes from the situation where many tree cavity living beetles finds themselves today. When existing trees are to pass out there will be no suitable inheritors yet. The work was initially to focus on cavities created from cut branches.

En marknadsundersökning om regelvirke : kvaliteter och kunduppfattningar

Today there is a widespread opinion that the woodmarket and the forest industry are dominated by a traditional way of thinking and not adapted to the customers of today; a lot of products are produced purely on routine. Also, there is a demand for improving the quality of sawn woodproducts. AB Karl Hedin wants to sort this out by increasingly adapt their products to the demands of the market, i.e. through introducing a short wallstud of standard length, "Hedinregeln". At tirst, the wallstud will be produced in lengths of 2,70 m and of guaranteed quality.

FE safety analysis of a high speed wood planer cutter. An alternative method to achieve the requirements of EN847 standard

In the last decades, high speed cutting has become an attractive technology in the wood industry. The possibility of reducing global costs in addiction with an increase in productivity, were the main reasons for the enlargement of the use of this technology. As usual, these advantages are accompanied by disadvantages that should be carefully analyzed. If on the one hand cutting forces are reduced with increasing cutting speeds, on the other hand, the centrifugal forces affecting the tool are higher. Exposed to such high loads, there is a considerable risk of tool failure that embeds hazards for both machine and workers.

Fuktskador i ytterväggar på grund av vattenintrång

Moisture damage in buildings is a serious issue that leads to problematic consequences and high economic costs. Despite the knowledge and awareness existing about moisture problems, extensive damager still occurs today. Studies of moisture in the exterior wall constructions shows that the issue if often caused by rain and water intrusion. These kinds of problem result in major costs usually because the companies have to replace the material and structural components and also in some cases tear down large parts of the buildings.The work includes moisture theory and descriptions of four different exterior wall constructions, wood stud wall with plastered facade, exterior wall with wood facade, exterior wall with concrete, and exterior wall with brick facade. Our thesis work describes how the constructions are affected and moisture damage due to water intrusion.

Modernisering av testutrustning

Rapporten beskriver arbetet med att modernisera en testutrustning för ett robotsystem. Den nya testutrustningen skulle moderniseras till att använda USB-gränssnitt istället för RS232-gränssnitt för kommunikation mellan dator och den övriga hårdvaran. Arbetet börjar med kravspecifikation och slutar med en fungerande produkt. I det innefattas en kortare förklaring av USB-gränssnittet och dess skillnader från RS232-gränssnittet, en utredning för att finna den bästa lösningen för att förverkliga USB-kommunikationen med utrustningen och konstruktion av elektronik för att styra signaler och spänningsmatningar till robotsystemet..

Modellering och styrning av flis till en sulfatkokare

At the Skoghall pappermill, sulphatepaper pulp is produced in a continuous digester originally from 1969. To be able to maintain a high level of production there is a need for a process with few disturbances. Variations in how well the wooden chips are packed in the digester is one form of disturbance. Today there are no available measurements on how well the chips are packed. Instead this is regarded as being constant.

Att utforska historisk slöjdkunskap genom klyvning och svepteknik. Ett exempel på forskning i hantverk

Uppsats för avläggande av filosofie masterexamen i kulturvård, 30 hp.

Hur påverkar naturvårdsåtgärder mängden av vedlevande insekter : Manuellt dödade träd vs självdöda

Today?s forest managers implement a large number of methods to increase the amount of dead wood in Swedish forests. They use everything from high cutting of trees to girdling trees and burning forests. However, implementation of these measures without proper knowledge of their consequences is a common problem. This study has been performed to increase knowledge about two of these measures, girdling and high cutting, and how these actions affect the number of wood-living insects living on dead trees.

Naturreservat : en bra naturvårdsåtgärd för att bevara enskilda arter och/eller bevara den biologiska mångfalden?

The examination of the adequate nature conservation methods in a natural reserve, to conserve a specific species and / or increase biological diversity is the subject of this study. This work is based on four species, that can be found during the Spring season, liverleaf, wood anemone, brimstone and woodpecker. The incidence and availability is studied and closely observed for these species in twenty forests, i.e. ten forests which are nature reserves and ten forests with the similar characteristics as the nature reserves habitat, but are not nature reserves in Gnesta mucipality, Södermanland. Measurements of the tree crown and the diameter of the tree trunks where noted to study how these factors could affect the outcome of the abundance and incidence of the four species.

Metodutveckling för analys av klorfenoler i jord samt analys av förorenad jord från ett sågverk

In this final thesis, an existing method for analysis of chlorophenols (CP) in bottom sediments has been updated and adjusted for analysis of chlorophenols in soil. The covalent bonds between the chlorophenols and the soil matrix were broken through basic hydrolysis and the chlorophenols were then separated from the water phase through addition of sulphuric acid followed by ether extraction. The chromatography was improved through extractive acetylation of the chlorophenols.The updated method was then applied on soil samples from a contaminated area (a former sawmill in Hyttsjö, Östergötland, Sweden).The analyse was preformed by GC/MS with respect to 2-MonoCP, 4-MonoCP, 2,4-DiCP, 2,6-DiCP, 2,4,6-TriCP, 2,3,4,6-TetraCP and pentachlorophenol (PCP).Contamination of chlorophenols in nature can be explained by the former use of wood preservative chemicals based on chlorophenols. In the 1960s and the 1970s these chemicals were used in Sweden, but due to their toxicity they were banned by the Swedish government in 1978.In Hyttsjö a pentachlorophenol-based product named Santobrite was used for several years. The concentration of PCP in the soil samples from Hyttsjö varied from 0.2->1.8 ng/mg dry substance.

Tillfällig partiell isolering av limfärgsbemålat trä vid behandling med fuktbaserade metoder - en jämförande studie av cyklododekan och mentol

Uppsats för avläggande av filosofie kandidatexamen iKulturvård, Konservatorsprogrammet15 hpInstitutionen för kulturvårdGöteborgs universitet2013:12.

Skötselförslag på utvalda nyckelbiotoper i Kalmar och Kronobergs län.

The objective of this study was to contribute with suggestions of nature preservation managements of selected forest objects of high nature values managed by the Swedish state-owned forest company Sveaskog. Many forests with high natural potential are relatively rare today due to modern forestry, where wood production is the main purpose. Sveaskog?s policy is to consider and to priority nature conservation on valuable objects. This assessment includes objects that in the future may develop into nature reserves.

Systemlösningar för plus- eller passivhus : En studie med syftet att lösa energibehovet för ett specifikt hus.

The purpose of the house which is the basis of this report is to be able present itself on the market as a relatively cheap and at the same time a climate friendly choice. The house is supposed to be able to be built anywhere in Sweden and the rest of Scandinavia in a short period of time. This puts demand on what kind of heating system the house can have, since not all places have the geographic advantage of being able to use geothermal or district heating. Therefore the heating system choices will only include those that are not limited by their geographic location. The house will be built in modules which only require the groundwork to be done before the house can be erected. In this report "System solutions for plus or passive-housing" a comprehensive literature search has been conducted as well as a number of calculations.

The impact of the EU Timber Regulation on the Bosnia and Herzegovinian export of processed wood

Illegal logging and its related trade is of great concern around the world. The European Union Timber Regulation (EUTR) is a regulatory approach by the EU to prevent illegal timber and timber products to be placed on the European Union inner market. This means the regulation affects both actors in the member countries as well as the actors exporting timber and timber products to the EU from non EU member countries. This study aims to study the implementation process of the EUTR in Bosnia and Herzegovina (B-H), and its preconditions. Institutional theory is used to understand and explain how the EUTR affects B-H organisations? business environment, and how the organisations choose to respond to the EUTR.

Hårdgörning av Asp

Hårdgörning av trä syftar till att göra materialet hårdare. Detta går att åstadkomma genom komprimering, det komprimerade materialet tenderar dock att återgå mot sin ursprungsform då materialet utsätts för fukt om ingen låsning sker. Låsningen kan ske mekaniskt i en treskiktskonstruktion som motverkar träets fuktrörelser. Dessa skivor har dock visat sig vara instabila och tidigare försök har uppvisat deformationer i form av kupning. Denna undersökning syftar till att utreda förutsättningarna för att använda komprimerad asp samt att ta fram underlag för framtagning av en kommersiell produkt.Praktiska tester har genomförts för att studera hårdhet, återfjädring och densitet hos det komprimerade virket.

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