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1720 Uppsatser om Heat treated wood - Sida 18 av 115
Kirunametoden-Jämförelse emot en konventionell injusteringsmetod
AbstractWith increasing population and increasing demands for comfort and thus an increase in energy demand, it is necessary to examine various energy-efficiency measures. This work deals with the ability to control the flow through the heating system to achieve the desired comfort with as little energy as possibleA heating system contains of different parts, roughly speaking, you can divide it to three main components: Heat source, Distribution and Heat emitters. All components are working together to bring heat to the building. What is examined in this report are different ways of adjusting the flow and supply temperature and how it affects comfort and energy use in a building.At today ?s date the conventional method is to use a high flow through the heating system, which affects pressure drop and cooling of the fluid.
En flödesutjämnande driftstrategi för Uppsalas fjärrvärmesystem : En ändrad styrning av framtemperaturen
This thesis examines a possible control strategy to minimize flow fluctuations in Uppsala?s district heating system. High variations in flow rate may lead to complications caused by hydraulic constraints in the district heating system. These complications, such as inadequate pressure and temperature levels, increase the risk of heat delivery failures. It is therefore important to avoid such situations both for the producer and for the customers.Typically, the forward temperature is controlled by using a rough correlation with respect to the outdoor temperature.
En studie om ensamkommande barns situation
In this study the semi structured interview method was used to explore what kind of knowledge one In State Authority: The Migration Board, and three Non Governmental Organisations: Red Cross, Save the Children and ISS- International Social Service have about the situation for separated children. Another purpose in this study was to explore if people who are close to the children are working for the best of the children and if their cases were treated with legal security. The result shows that the children?s cases are not treated with legal security and some of the children suffer psychologically from separations from the families and other children need new families because they were maltreated. The result also shows that there are signs that separated children are discriminated compared to children with a Swedish background..
Skogspolitik i Sverige
For a long time the Swedish forests were used by the landowner?s mainly for providing wood to the household itself. The wood was not, to a greater extent, considered a product to be sold. During the 1800s the industrial era led to a demanding need for wood in the industry and thus the use of forest, forest production kicked off. The forest production was not regulated by law, which led to a differentiated forest production over the whole country without consideration of re-growth.
The French market and customers? perceptions of Nordic softwood offerings
The study of the French market for softwood has been done in collaboration with VIDA AB. The aim of the study was to investigate important product quality and service quality dimensions, the customers? perception of the offering and generally describe the French market and present actors.
The market for softwood around the world changes over time and new markets can mean opportunities for the sawmilling industry. The French market is the second biggest European market for softwood, has had presence of actors with sourcing of raw material from the Nordic countries for decades and there is a growing interest for building with wood.
Theory being used is about the different dimensions that make up the total quality of softwood, together with intangible dimensions making up the total offering that helps the sawmilling industry to create positive perceived value for the customers.
Methodological approach in the study was a case study research design, aimed at providing knowledge about one specific subject in one context. The general description was mostly carried out by literature studies and data from various statistics sources.
Mätramar för vederlagsmätning och timmersortering på sågverk
The measuring of logs is important in the sawmills process to the sawn products. The technology of automatic wood measurement is continuance developing. This study has the purpose to see how the different techniques and the routines works of measure frames for determining of wood value and sorting in sawmills. The study is performed as a literature study and a survey. The survey includes some of the Swedish sawmills that produce more than 10 000 cubic meters sawed products per year.
Termisk analys av kompakta jordvärmesystem - Sensitivitetsanalys och korrektions faktorer baserat på fältmätningar i referensanläggningar i Östergötland
Chapter 1 defines the aim of the project and gives a general orientation about ground heat extractors. In chapter 2 physical processes that could be expected to be involved in the heat transport around a ground heat exchanger are discussed. It is shown from a literature study what amount of moisture transport due to thermal gradients there could be expected in a ground heat exchanger. The conclusion is drawn that the moisture gradient (Sr) is of same magnitude as the driving temperature gradient (°C). At the expected amount of increased moisture around the pipes the moisture transport could be considered to have a little effect on the brine temperature.
Trähägn en tänkbar metod för viltskydd i Svenskt skogsbruk?
This survey was made to investigate the possibility of using an alternative method of fencing inSwedish forestry. The most common way of fencing in Sweden today is made by a two meter highmetal net that is attached to turned impregnated poles. The fencing methods that have beeninvestigated is a fencing system made completely out of wood so called ?German wood fence?.Browsing of game in forest regeneration areas is often a big problem and some kind of protection ofthe plants is often necessary. There is several ways of building fences and the most common way isto use metal nets and impregnated poles, this leads to a problem when the fence has profiled itspurpose.
Lagring av kyla med horisontella markvärmeväxlare för kylning av koncepthus i Mellanöstern
Norconsult AB has developed a solarhousing concept, a house designed for the warm climate in the Middle East andwith large quantities of solar panels installed. The cooling system for the house was designed in an earlier report, the purpose of this thesis is to investigate the possibility of short and long term storage of thermal energy via an underground energy storage volume.Two different designs of the storage and three different filling materials have been integrated into a model to simulate different cases. The first design consisted of pipes installed in the ground, without insulation. The second design consisted of an insulated concrete box installed to prevent thermal energy from the surrounding soil to flow towards the lower temperature regions within the storage. The three different filling materials were dry saudi sand, water saturated saudi sand and the filling material used by the client for energy storage in Sweden.The results from the simulations show that neither of the designs, regardless of the filling material, managed to extract enough thermal energy from the house to the ground to uphold the demands of indoor climate.
Uppvärmning med spannmål och trädbränslen :
This examination work brings up opportunities to invest in a construction for heating with grain
or pellets on farm level.
As example we have chosen Fröberga Gård which is a farm located in Östergötland outside of
Söderköping.
The farm`s residential buildings is to day heated with oil and electricity.
The result of our investigation shows that heating with grain is the best alternative, partly because
of economical issues but also because you can grow the grain on your own farm and by that you
can get better economy in your seed cultivation.
To grow 16 tonne of grain as is needed demand gives a insignificant increase of work.
Further an advantage is that no investment in machines is needed because all the machines witch
is needed already is in use on the farm.
In a situation where a new investment is needed as in the case we studied, is it often profitable to
invest in a integrated furnace. Because all the components are well adapted to each other, and
because that gives a high efficiency.
If you already own a well working furnace is it often most profitable to connect a burner to it.
It is important to know that heating with grain need more work than heating with pellets, because
the high contents of ash in grain.
Even if you choose pellets instead of grain the calculation shows good results.
Because peat is an excellent but fairly untested raw material for pelletsproduction we have
chosen to watch little more on its quality and conductions.
We discovered that peat has a high heating value which makes it possible to raise the heat value
in pellets through mix up peat and wood. Or you can make pellets with only peat and get a pellet
with high heating value. Even the calculation with peatheating shows good results..
Det är ett givande och tagande : Samverkan mellan socialtjänst och skola
The title of this essay is ?Collaboration between social services and schools?. Research shows that many children and youth who are badly treated are not noticed and do not receive the help that they need. This could be due to the lack of collaboration between different authorities and professionals. The purpose of this study is to describe and analyze how the social services and schools are collaborating in terms of children and youth who are badly treated or is at risk of being badly treated and to identify what factors make collaboration possible and hinder it.
Två presentationstekniker för grafer : deras styrkor respektive svagheter inom en bioinformatisk kontext
This degree project has been carried out in cooperation with Enertech AB in Ljungby and is pilot study to automating all current manual soldering. The soldering process accounts for a large part of the processing cost in the production of a heat pump. The process is also a quality risk and has a major impact on the lifetime of the final product.The Main task of this project has been to evaluate automation of the soldering process, to develop automation solutions and a principle layout, to draw the design changes required for the automation and to calculate the supposed solution.This pilot study has resulted in a suggested automation solution using laser as a heat source for soldering. Calculations of the solution show that a automating a laser soldering cell is very profitable..
Epixylic, forest-interior bryophytes in young stands : importance of local environmental variables, propagule sources, and distance to bordering woodland key habitats
The reduction of coarse, dead wood is considered to be the biggest threat to flora and faunain boreal forests. Extensive harvest of logging residues would increase this reduction evenmore. However, the role of dead wood created at final felling for boreal, epixylic species isstill largely unclear. It is therefore of interest to examine whether epixylic species inhabit thedead wood in young, boreal stands, especially species considered to be confined to forests inlate successional stages.The aim of this study was to investigate whether forest-interior species in fact can inhabitearly-successional forests arisen after logging. The study was conducted in young standsbordering dead wood rich woodland key habitats.
Vidareutveckling av PV/T-receiver för koncentrerat solljus
The rising demand for electricity and heat raises a big challange for the society and engineers. Many products have been introduced to the market to supply more energy to the energy systems. Absolicon AB is a Swedish company that develops and markets a combined heat and power generating product. The product, Absolicon X10, uses a parabolic trough to concentrate the radiation of the sun onto a receiver. The receiveris equipped with mono crystalline solar cells and is cooled by a circulating liquid media.
Traditionell skidtillverkning: ett kunskapskomplement till dokument?ren Skidmakaren i Gielas
Archaeological findings show that ski manufacturing goes back thousands of years in the Nordic region. There is a wealth of literature and film that deals with the subject, but it can be difficult to get an overall picture of how a specific type of traditional ski has been made. The starting point is the documentary "Skidmakaren i Gielas", where the viewer can follow Alfred Israelsson as he makes a pair of skis out of birch wood. However, the documentary lacks important information about how the skis are actually manufactured. Length, width and certain working steps are disclosed.