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645 Uppsatser om Archaeological wood - Sida 36 av 43

Short-term responses of the field layer vegetation in a south Swedish deciduous forest after establishment of wild boars (Sus scrofa)

Inside the south Swedish national park Dalby Söderskog, wild boars (Sus scrofa L.) have been visiting since 2010. The presence of wild boars has earlier been proven to impact both soil and vegetation characteristics, both positively and negatively. Still, there is a lack of knowledge regarding the rooting effect on the vegetation in deciduous forest within the native range. In this study, I have compared the field vegetation collected before and after the invasion of wild boars in 74 permanent experimental plots. More specifically, the study aimed to qualify the effect of wild boar rooting on cover ratio, species richness and species composition in a temperate deciduous forest.

Bioenergi från röjningsgallringar : en jämförande studie av fyra flödeskedjor från avlägg till förbrukare

When the Swedish Forestry Act was changed in 1994, brushing of young stands became non mandatory. Since then the annual need for brushing in the country has increased by about 100 000 hectares per year. In later years the price for biomass energy has increased to the same level as pulp wood. The high price on biomass energy and the large areas of stands in the need of brushing has created a new market with its own technical, economical and environmental conditions. There is a development of various techniques to manage the forestry stands with late brushing.

Småskalig biobränsleeldad kraftvärmeproduktion : teknik och investeringsutrymme

To achieve the requirements to decrease emissions of greenhouse gases by 20 % by 2020, Swedenneeds to increase its use of bioenergy. In doing so it seems natural that those who already haveaccess to large amounts of biofuels in the form of by-products such as straw, wood chips anddigestible materials take advantage of these assets locally. By combining production of heat withpower production at the farm it may be possible to not only reduce the direct use of fossil fuel forheating but also reduce energy costs.The purpose was to simulate different cases of using a small scale biofueled combined heat andpower plant for farm-based systems. A MatLab-model was developed and used to draw conclusionsabout the costs for production of heat and electricity with different conversion technologies.The model uses climate data to simulate the variations in heat energy demand on a day-to-day basis.The given heat demand is the base of the simulation and from this the possible electric output iscalculated. This study has focused on the impact of the following properties: electric-, heat- andtotal efficiency, fuel, fuel price and specific fuel requirements.

BIM Building Information Model : Hinder & Drivkraft

The  construction  industry  is  a  costly  business  such  in  respect  of  capital  for  most construction defects which then require rework, tear down and rebuild again. This study is  meaningful  awareness  of  tools  that  can  reduce  this  best  through  communication  and information sharing between the parties.  The  construction  industry  is  known  as  temporary  projects  organizations,  where  the construction  project  consists  of  several  actors  who  have  to  communicate  and  share information  between  them  to  avoid  mistakes  later  in  the  build  time.  These  actors  are bounded together thus for the duration of the project, then broken when the project has reached its end. The challenge here is for these actors to apply a tool that can help and simplify communications, information sharing, and perhaps the most important aspect is to  create  a  routine  for  the  association  and  the  shattering  of  these  actors.  To  implement such  behavior  using  a  tool  such  as  BIM  in  the  industry  whose  size  perhaps  is indescribable may be a very hard task.  BIM (Building Information Model) could be seen as the solution to this problem because it  acts  as  a  portal  where  the  actors  involved  must  sign  in  and  communicate,  share information, and eventually create a behavior, a routine for this association and division of  the  actors  following  the  end  of  the  project.  The  technology  could  help  the  involved from  the  beginning  of  the  project,  already  in  the  model  stage,  break  down  and  prevent any construction barriers when the building has been placed in the works.

Torrefaction of biomass : a comparative and kinetic study of thermal decomposition for Norway spruce stump, poplar and fuel tree chips

Stump biomass is energy rich and stump harvesting for use as fuel become more and more interesting in Sweden. Swedish Forest Agency (2009) has estimated that stump harvesting in Sweden would respond to an annual energy supply of 57 TWh/year. However, stump has not been recognized as a bioenergy resource in Sweden. Suitable methods for pre-treatment of stump are probably of great importance to make it accepted as fuel. It is therefore rewarding to carry out an investigation in this area for stump. This report represents results from a diploma project, which was aimed to develop a fixed bed reactor for experimental study of biomass torrefaction, followed by TG analysis and kinetic modelling employing Ozawa method and different kinetic models including one-step and three-pseudo-component models.

Avsättningar i pappersmaskiner : Utbildning och förslag till processförbättringar

Deposits can be formed in the paper machine due to sticky materials from wood and recycled paper. These deposits get stuck on process equipment and cause the product quality to deteriorate and the efficiency of the paper machine is reduced. The purpose of this thesis is to increase the understanding about deposits among machine operators, and to suggest methods that can be used to reduce the amount of deposits formed in Bravikens paper machines.To fulfill the purpose of the thesis a pre-study, a literature review and interviews with machine operators and production staff, were carried out. These methods led to the planning and creation of an education about deposits for machine operators.The education about deposits for machine operators consisted of an interactive lecture to introduce the subject of deposits and a subsequent discussion. This approach was chosen to give the machine operators the opportunity to discuss their work situation on the paper machines related to their new knowledge about deposits.

Trädetaljer i exteriör arkitektur : En rapport om hur arkitekturen kan tillåtas framhäva trä som byggnadsmaterial i utvalda exteriöra detaljer för ett äldreboende med massiv trästomme

Arkitektfirman Kolman X Boye Architects har fått uppdraget att upprätta bygglovshandlingar för ett äldreboende. Det är ännu ej bestämt i detalj hur byggnaden skall uppföras men beställaren önskar att byggnaden uppförs i träbyggnadsteknik. Äldreboendet projekteras för 54 stycken lägenheter fördelat på sex stycken våningsplan och en total bruttoarea på strax under 6000m2. Ingen lika hög träbyggnad med denna verksamhetsklass avseende brand har tidigare uppförts i Sverige.Vår uppgift och utmaning i detta arbete har varit att reda ut problematiken kring projekteringen av exteriöra detaljer för höga hus i trä. Utifrån kända problem avseende brand, akustik och fukt har sedan ett antal detaljer som påverkar det estetiska uttrycket projekterats.

"En gång till!" : en kommunikationsetnografisk studie om andraspråksinlärares deltagande i förskolan

The aim of the thesis was to better understand how second language learners becomes lingual participants in a Swedish preschool. Using the following research questions: In what situations are SLLs lingual participants at the preschool? What does their emerging language look like? Are the participation any different considering children's time in the new L2 context? What kind of support does SLLs receive at the preschool?Two focal children at the same preschool was studied with ethnography of communication as method. The focal children chosen were one girl (Mandarin L1, 4.0 yrs) who arrived to Sweden and started the preschool two months ago at the time of the study, the other a boy (Serbian L1, 3.9 yrs) who started preschool and learning the L2 one year and two months before the study. Situations where the focal children interacted with other children or adults were analyzed. Results showed that the focal children in interaction with each other understands some of the others intentions before being able to speak about them in the L2.

Bruka utan att förbruka - när andra intressen än ekonomin får styra

To have a forest area close to the city is of great importance for the city population?s well being. Children develop their motor skills, concentration and imagina-tion and the adults have a place to shake of the stress from work. Forest areas are used to exercise at, play in and to find a moment of peace and silence. The urban forest and the old farming pastures at Markussonvallen and Per-Isakssonvallen already has natural assets worth to preserve and a great potential to create more. The goal is to develop a forest with a variation of tree species and ground vegetation that will appeal to the human senses and different animal species such as birds, insects etc.

Emissioner i slutna utrymmen Med speciell inriktning på emissioner av formaldehyd och organiska syror

This study aimed to evaluate the levels of formaldehyde and organic acids that can build up within enclosed spaces. Another goal was to compare two types of paints that can be used as coating barriers within showcases and in turn compare them to the modern, and by many highly recommended, material of Marveseal®. A low volatile waterborne alkyd/acrylate paint and a two component polyurethane paint was compared to Marveseal® in two series of experiments. One series measured the level of formaldehyde, and thus the effectiveness of the three chosen barriers, and the other series measured the level of volatile organic acids, both the acids emitted from the paint itself, and that of the wood. One box in each series were not treated at all and was used as a reference.The fact that different types of materials emit volatile organic compounds have long been known.

Träplastkompositer ? ett material för framtiden? : en kvalitativ studie om marknadens önskemål för att göra träplastkompositer till ett mer attraktivt material för framtiden

Minskad efterfrågan på traditionella produkter från skogsindustrin kombinerat med ökad efterfrågan på icke-fossila material medför att företag inom skogsbranschen alltmer intresserar sig för nya produktsegment. Holmen New Business Development, en forsknings- och utvecklingsavdelning inom företaget Holmen arbetar med att utveckla produkter där trä kan ersätta traditionella alternativ. En möjlig produkt för avdelningen är Wood Plastic Composite (WPC), ett material som består av en kombination av en plastmatris och ett träbaserat fyllnadsmaterial som kan ges olika egenskaper vilka skiljer sig från rena trä- och plastmaterial. Syftet med denna studie var att undersöka hur designers och produktutvecklare inom olika svenska branscher ser på användandet och utvecklingen av WPC inom sina produktområden, både idag och i framtiden. För att undersöka detta har 18 kvalitativa intervjuer genomförts med företag inom möbel-, köks-, fönster-, dörr-, staket- och trallindustrin. Studien visar att ett lågt pris, hög beständighet mot till exempel röta, fukt och mögel samt att materialet går att bearbeta på samma sätt som trä är de mest önskvärda attributen hos framtida WPC-material. Miljövänlighet hos produkten är ett attribut som respondenterna tror kommer få större betydelse i framtiden men som kunderna inte är beredda att betala för idag.

Stengrunder och gränser : en studie av kontinuitet från äldre järnålderns stengrundsbygd till nutid

This thesis studies settlement continuity on Gotland between approximately AD 200 and AD 1700. The method used is to calculate correlation between the geographical distribution of all known Iron Age stone-wall-houses (on Gotland known as "kämpagravar") and all farms included in the detailed taxation maps from approximately 1700. The number of remaining house foundations is between 1800 and 1900. A model to estimate the number of removed foundations is presented. It is based on the assumption that the settlement density was proportional to land use around 1700, and that the rate of removal is related to the current land use.

Kartläggning och analys av försörjningskedjor, Setra Group - två fallstudier :

This study concerns mapping and analysing two different Supply Chains at Setra Group. Setra Group is Sweden?s biggest producer of solid wood and is primarily owned by Sveaskog, Mellanskog and LRF. The Company consist of twelve sawmills, five planning mills and an organisation for distribution of building material. This study maps one chain for Swedish Glulam standard beam and one chain for solid pine flooring on export to Japan. The glulam chain is based on spruce as raw material and includes all actors between sawmill and the Swedish building material retailers.

Hjortpark, kronoskog och ladugård : En bebyggelseundersökning av Skyttsie Hage på Skanörs ljung

This essay is about a deserted medieval habitation called Skyttsie Hage which is located in the south of Sweden in the Scania province where it lies on a moor on the Falsterbopeninsula. Remains of five to six larger buildings have been found here with a surrounding earthwork, although it's not known for sure what kind of habitation they have been part of. Local folklore from the 17:th century states the area as a place where pirates lived, and that this was the reason for it's devastation. Another says that there once stood a breedingfarm belonging to the danish crown. Archaeologists have made several speculations which includes a deer park, a royal estate, an isolated farm or a smaller village.

Modellering av flisstack

Bioenergi är en stor industri i Sverige och står för en betydande del av energiomsättningen. Bioenergi i form av flis förvaras runt om i landet på hög i väntan på förbränning. Då högarna läggs upp startar olika processer som värmer upp stacken, ofta till temperaturer på 50°C under det första dygnet. En vanlig ansats i litteraturen är att denna temperaturstegring beror på aerob nedbrytning. Arbetet ämnar undersöka om denna uppvärmning endast beror av mikrobiella aktiviteter.

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