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697 Uppsatser om Wood density - Sida 24 av 47

Inverkan av röjning och gödsling på mikrofibrillvinkeln i tallens (Pinus sylvestris L.) ungdomsved

Tall (Pinus sylvestris L.) är ett av Sveriges viktigaste trädslag. Med ökad efterfrågan på vedråvara samt ökade krav på naturavsättningar är det viktigt att öka produktionen i skogen. Röjning och tidig gödsling ger ökad volymproduktion men kan ge icke önskvärd påverkan på vedegenskaper som ökad mikrofibrillvinkel (MFV). MFV är vinkeln mellan mikrofibrillerna i cellväggens S2-lager och cellens längdaxel och påverkas av ståndort samt konkurrensen om ljus och näringsämnen. Höga MFV resulterar i sämre kvalitet på papper och sågade trävaror.

Automatisk detektering av akustiska resonansfrekvenser i trästockar

In order to measure the quality of the logs, one can with help of Fast Fourier Transform technique get the signals resonance peaks. With help of these peaks you can see whether the quality of a tree is good or bad. This report contains the work of a where a program has been developed to be able to process a vibration created by an automatic hammer hitting on a log of wood. From the processed signal the program should be able to show both the raw wavesignal and the processed measured data from the resonance peaks. Beyond the raw wavesignal and resonance peaks the program should also be able to control the automatic hammer.

Till synes orörd skog : naturvärden och kulturhistoria i Rekdalen under 400 år

Nature conservation has for a long time been founded on the assumption that high ecological values depend on low human impact. In Sweden this has led to forests with these characteristics being strictly protected from human influences. However, it is also known that historical land-use can enhance ecological values in forests. Mountainous forests in Sweden, which have not been affected by modern forestry, have for a long time been considered as untouched by people. However, forest history research has in recent years shown that even these areas have been used by people for a long period of time.

SILO 72 : Ombyggnad av Lantmännens silo i Östra Hamnen, Västerås

This project includes a small study of Västerås city's housing needs, and a proposal on theuse of the property 1:207, Lantmännens silo in the Eastern Harbour, Västerås.The project intends to produce a basic study of the useful systems for this rebuilding projectwith regards to sustainable development and energy saving light buildings.The end result, which consists of a detailed visualization of the proposal, intends to becomean iconic natural focus for the Eastern port of Västerås and an example of the use andadaptation of existing structures.The property must also link the eastern parts of Västerås with the center through anextension of Mälarleden.The work has been performed through literature studies, site visits, contacts with the City ofVästerås and by calculations.The proposal consists of architectural proposals drawings and visualizations.Furthermore, a suggestion is given of how the property can be used and fitted into theoverall plan for urban density development currently underway in the city of Västerås.Computer programs used have been Microsoft Office Excel, AutoCAD and ArchiCAD..

Supply Chain Configuration : Ens studie av förbättringsarbetet "Supply Chain  Configuration

In order to measure the quality of the logs, one can with help of Fast Fourier Transform technique get the signals resonance peaks. With help of these peaks you can see whether the quality of a tree is good or bad. This report contains the work of a where a program has been developed to be able to process a vibration created by an automatic hammer hitting on a log of wood. From the processed signal the program should be able to show both the raw wavesignal and the processed measured data from the resonance peaks. Beyond the raw wavesignal and resonance peaks the program should also be able to control the automatic hammer.

Att skriva ett kurskompendium för tätkontroll och läcksökning.

  SAMMANFATTNINGLackage fran en komponent i form av vatska eller gas ar ett ofta underskattat problem som kan geupphov till samre produktkvalitet, energiforluster och i slutandan ge ekonomiska konsekvenser omlackaget blir for stort. Det finns dessutom en miljo- och halsorisk om en produkt eller komponentlacker ut storre mangder kemikalier eller metaller. Kan lackaget minskas finns med andra ord storavinster att hamta.Nolek AB bygger instrument for att hitta lackage, lacksokning, och mata lackage, tatkontroll.Foretaget arrangerar utbildningar for sina kunder men har tidigare inte haft nagot uppdateratmaterial for detta andamal. Syftet med examensarbetet ar att producera delar till ett nyttutbildningspaket inom tatkontroll, lacksokning och provtryckning samt att undersoka teorier forskrivande av pedagogiska texter. Arbetets resultat utgors av ett kurskompendium samt enPowerPoint-presentation kopplad till kompendiet.

Skogsbränsleuttag vid förstagallring och dess påverkan på beståndsutveckling : simulering i Heureka med olika skötselprogram

Stands where pre commercial thinning has been ignored or inadequate often tend to have high stem density and low average diameter when they reach heights of thinning. In such stands, it can often be expensive to do a conventional pulpwood harvest as a first thinning. This study investigates the development of the stands and the economic outcome of forest fuel extraction, or a combined harvest as alternatives to the ordinary pulpwood harvest. Simulations in Heureka StandWise were performed for two thin and dense stands, which were constructed by data from the Swedish National Forest Inventory. The simulations show that the extraction of forest fuel in first thinning at an early stage can provide higher net revenue compared to conventional pulpwood harvest at the same time or later.

Automatisk plastlisthanterare

Today a lot of goods is transported on wood pallets because it?s practical and enabels a fast way to load cargo. The drawbacks with pallets are that they weight a lot, are big and are relatively expensive. Therefore IKEA has developed plastic lists that can replace the europallet in some applications. In this examwork an automatic handling equipment for plastic lists are design from a requirement specification to a finished machine.

Brännkammare för träpulver : Teoretisk analys och praktisk försök

The thesis describes a completely new biofuel system to generate particle-free heat from combustion of ash-containing biofuel particles at high temperatures.The suggested system gives opportunities to introduce biofuels in new areas.Main components in the suggested system is a heat radiating combustion chamber intended for pulverized wood, combined with regenerators to extract heat from flue gases and simultaneously preheating the combustion air.The thesis contains a description of the suggested system, theoretical considerations, calculations regarding the combustion, and includes results from tests performed.The results from calculations and tests performed concludes that the system is workable and possible to apply..

Skogsentreprenör 2007 : en kvantitativ studie av organiserade skogsentreprenörer i Sverige

SMF Skogsentreprenörerna is a nationwide organisation for Swedish forestry contractors. It has about 750 organised companies with somewhere around 1500 logging machines. These machines perform well over 50% of all yearly landed wood in Sweden. The members of SMF also performs more and more of other functions in Swedish professional forestry, such as soil scarification, planting and pre-commercial thinning of younger stands. In order to determine what major priorities SMF should focus on in the future a member survey was initialised and carried out by SMF together with Daniel Larsson-Snygg, student at the swedish university of agricultural sciences SLU. This report presents the result of this survey sent out to all members of SMF. It is intended to answer a number of questions about their entrepreneurship such as: What different kinds of work do these companies perform? How many machines and employees do they have? How old are the company owners and their employees? What are their thoughts about the future of their business? How well does SMF serve their members needs?.

Enkätundersökning hos markägare inom SCA Skog Ångermanlands Skogsförvaltning

This report is a joint venture with SCA Forest, Ångermanlands forest man-agement area. The purpose of the study is that SCA Forest wants to know what the landowners in Ångermanlands forest management area think about SCA Forest and who they deliver their timber to. SCA Forest is the largest private landowner in Europe, with an area of about 2.6 million hectares. Today, SCA offers lumber, wood products, tis-sue and packaging and has factories all over the world. SCA Forest has five forest management areas in the north of Sweden, with the headquarters in Sundsvall. A questionnaire was sent to 265 landowners, where they had to answer 15 questions with possibilities to give comments. The survey was sent out on 21 of February with a response requested by 3 of March 125 landowners responded to the survey, giving a response rate of 47%.

Rosengårdsstråket : tankar om förankring och identitet

This thesis is studying Stråk* in an urban contexts. Thiswill be achieved through a study of Rosengårdsstråket inMalmö based on the question "What is a Stråk?".Malmö has experienced a major change in the last 15years. From being an industrial city with economic problems,Malmö is now part of the dynamic Öresund Region,and a knowledge city with great optimism. New parts ofthe city is about to grow up that reinforces the image ofMalmö's new identity.The next step in Malmö's development is to make thecity even denser and interconnect the inner city and thesuburbs to create a more sustainable city.

Naturlig haptisk kraftåterkoppling från volymdata

As the volumes are entering the world of computer graphics the pure volume visualisation becomes a more important tool in for example research and medical applications. But the advance in haptics --- force feedback from the computer --- is behind. In volume haptics no equal to the proxy method so popular in surface haptics has yet emerged. Some implementations of volume haptics even use surfaces as intermediate representations so that surface haptics can be used.The intention of this work was to create natural feeling haptic feedback from volumetric density data using pure volume haptics. The haptic algorithm would be implemented in Reachin API for the Reachin Desktop Display, together with other parts to build up a usable volume visualisation environment.To achieve the feeling of stiffness and friction dependent on tissue type, a proxy based method was developed.

Predation av sandräka (Crangon crangon) på juvenil piggvar (Psetta maxima) och juvenol skrubbskädda (Platichtys flesus) : betydelse av yngelstorlek för överlevnad hos piggvar och skrubbskädda efter bottenfällning

Turbot (Psetta maxima) and flounder (Platichthys flesus) are two species of flatfish both having their nursery areas around the shores of Gotland in the Baltic Sea. The common brown shrimp (Crangon crangon) is a known predator on newly settled plaice (Pleuronectes platessa) in the North Sea area and is also found in the Baltic Sea. Experiments were carried out to see if the brown shrimp is predating on juvenile turbot and flounder, and if so on which sizes, and if the brown shrimp prefers any of the flatfish species, and also to see if there is a difference between day and night in density of the shrimp, i.e. when the fish might be subjected to predation. The results showed that predation decreased with size for both turbot and flounder.

Stenebergs sockerbruk: en fallstudie av en timmerstomme fr?n 1739

Stenebergs sockerbruk is a large log-timber construction, purpose built as a sugar refinery in 1739 and is one of Sweden's oldest industrial buildings constructed entirely out of wood. Despite receiving the status of a listed building (in Swedish: Byggnadsminne) in 1977, there exists today a surprisingly low amount of documentation of the building itself. In order to enhance the existing and lacking building documentation, this case study aims to shed light on the building's log-timber built frame, focusing on how it was constructed, how the long lengths of its walls were handled and what type of joinery and tools were used. A thorough investigation of the building is conducted on site, followed by gathering of information which is then presented through text and illustrations. The findings indicate the orientation of timbers, location of joints and scarfs as well as tool marks which together contribute to the forming of a basis of understanding of the building's construction..

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