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528 Uppsatser om Shelter wood - Sida 20 av 36

Limmade träförband

Utvecklingen av förbandsmetoder är viktigt för att utveckla konstruktionslösningar. Under det senaste decenniet har forskning på limmade förband utförts, främst på inlimning av stålstag och plattstål i limträ. Förhoppningen är att spänningen ska fördelas jämnare i förbandet och att brott ska kunna undvikas. Hypotetiskt sett skulle det kunna göra knutpunker utan synliga förband möjliga vilket även skulle gynna arkitekternas önskemål.Genom en sammanställning av tidigare forskning dras en jämförelse mellan testresultaten och en antagen knutpunkt som belastas av egentyngder och variabla laster. På så sätt kan limmets kapacitet konkretiseras.

Lämpliga främmande trädslag för Kalmar och Mönsterås kommuner

This report concerns the for Sweden foreign tree species hybrid larch, hybrid aspen and poplar, and focuses on the area Kalmar and Mönsterås municipalities. The report shows that there are not only advantages with these species. The larch, the most common of the alien tree species has the greatest problems due to that its timber is difficult to sell in the area but also the Larch´s poor pulp quality and is more likely to be damaged by wildlife than the spruce is. Hybrid Aspen is much easier to sell and is used like regular aspen for match wood and textile pulp. Its disadvantage is the high cost for plants and to prevent damage from wildlife.

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.

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.

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.

Inventering och riskanalys av skolskjutshållplatser : kvalitetsäkring med avseende på trafiksäkerhet

In Trollhättan municipality approximately 700 school bus stops are in service. To ensure high quality of the performance of school bus operations, with focus on traffic safety, it was decided to conduct a survey of bus stops including assessments of risks.This master thesis aims to identify the factors affecting road safety at bus stops and pedestrian connections, and to conduct an inventory and analysis of selected sites in Trollhättan municipality. The work also aims to show examples of how risk assessment should be performed in future studies. A risk analysis model provided by the Swedish Transport Administration is supplemented and used in a field study. The risk assessment is based on, inter alia, traffic flow, visibility distance, lighting, speed of traffic and the presence of bus shelter.

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%.

"De har ingen självklar plats någonstans" : - En studie om socialarbetares erfarenheter av multiproblematiken kring insatser och insatsbehov till våldsutsatta kvinnor med missbruksproblematik

Previous research shows that women who are victims of intimate partner violence and also have asubstance abuse have difficulties getting access to services to aid with their experience of violence.This study has examined social workers experiences of working with women with these problems,what types of services are provided and how their service needs are assessed. The study has ahermeneutical approach and the data consists of interviews with nine social workers in lines ofwork that come into contact with women in the previously described client group. The data hasbeen analyzed using content analysis. The result of the study indicates that women who are victimsof intimate partner violence and also have a substance abuse do not get their needs provided forthrough the current services in the field of social work. These women are described as havingcomplex problems and are therefore in need of more and other services than those currentlyprovided.

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..

"Anders Andersson hade eld i sin tjärdal" : en analys av Jonas Åströms dagböcker 1868-1891

"Anders Andersson had a fire in his tar-kiln ". Analysis of Jonas Åström 's peasant-diary 1868-1891 Peasant diaries are notes written by farmers, crofters and other people connected with small-scale agriculture. The notes give unique information about diverse aspects of rural life, for example, personal relationships and work, travel and regularity of church attendance. One such diary was written by Jonas Åström who lived in the county of Västerbotten, Sweden. The main aim of this study is to describe the work done by farmers in the 19th century, focusing on their use of forest resources, as recorded in his diary.

Retention of stumps on wet ground at stump-harvest and its effects on saproxylic insects

Low stumps represent on their own up to 80% of the dead wood remaining on clear cuts and therefore supply suitable habitat for saproxylic insects i.e. insects depending on dead wood for their survival. Recent stump harvesting activities threaten this substrate of ecological importance and increase the anthropogenic negative impacts on these species. Because of technical and environmental reasons (nutrient leakage, erosion) guidelines for stump harvesting recommend to retain stumps standing in wet parts of clear cuts. However, stumps in wet positions might not be a satisfactory substrate for saproxylic insects and therefore might not be as much used as stumps in dry positions.

Förbränning av träpellets och pelleterad halm i en 40 kW rosterreaktor

The project focus on combustion of softwood pellets and pellets in a 40 kW grate fire reactor at TEC-Lab. Dept Applied Physics and Electronics at Umeå University. Experiments were performed at four primary airs to fuel ratios (0.7 to 1.3), where aspects such as temperature profile, levels of gases (CO and NO), sintering-/-slagging and unburned fraction of the ashes were studied. Four different fuel loads were used for wood pellets (10, 20 and 30 kW) and one fuel load for straw (10 kW). Combustion of straw proved very difficult to ignite, and also led to other combustion-related technical problem such as slag formation due to the relatively low melting temperature-/-slag temperature of the straw.

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