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662 Uppsatser om 3 dimensional wood composite - Sida 34 av 45
Fiberföstärkning av Limträbalkar
Glulam is a product that was engineered to make use of timber in a more efficient way. Bychoosing timber of similar quality and discarding natural defects during production, thedevelopment of a stronger cross-section is achieved.Carbon fiber is a relatively new material with a high tension capacity. This feature is used toexamine how the bending capacity of the beams improve by adhering carbon fiber laminateson the lower edge of the beamsThe strength of the material is tested with three experiments: carbon fiber on the bottom of thebeam (a), carbon fiber attached to the lower sides of the beam (b) and carbon fiber in thebeam, covered with a layer of wood (c)The results show that the first case, where the carbon fiber is attached to the bottom of thebeam, gave the best result with an increase in capacity of 59 % compared to the nonreinforcedcontrol. The other two cases also show an improvement in capacity, beam-type 3had a capacity increase of 47% and beam-type 4 increased with 25 %Tests were also made with glulam beams reinforced with fiberglass, but these tests were notanalyzed in depth because the purpose was to compare the capacity to carbon fiber. Thisbeam improved its capacity by 40.3%.The tests show that carbon fiber as a reinforcement material for glulam is a good choice whenthere is a requirement for stronger cross-sections in both new production and renovation ofold buildings.
Den syd?stg?tska d?rromfattningen: en unders?kning av Kisa tingshus d?rromfattning
Kisa Courthouse in the south of ?sterg?tland is a house built in the early 19th century with a typical neoclassical style. With clearly regular symmetrical wooden facade scheme with a central main entrance. The main entrance is a wooden double door with richly decorated portico. the crown moulding above the door consists of a band of dentils with a cornice moulding at the top.
Design av utomhusträdgård i Dubai :
To plan and build a garden in Dubai has other conditions and challenges than what you experience in Sweden. The heat, wind and lack of water makes the need for durable plants, a good design and landscaping important if you want to have the opportunity to use your garden during most of the year. The soil is poor of nutrients, alkaline and sometimes saline, witch makes supplying the soil with organic material and various fertilizers necessary if you want to be able to plant a bigger range of plant material in your garden. Another important part is to provide your garden with a good irrigation system that should be put into the ground before planting so that the plants are given a more even irrigation.
It?s relatively green scenery you meet and to me it?s in a way surprising since the country with its climate is rather harsh for the purpose of supporting plant life.
De Paard - Visions of Playtopia
Playsam in Kalmar AB are world famous for their design of the toys they sell. Together with their CEO Carl Zedig the goal was to find a new product for the company. The process has far from been linear, I started off in one direction, got rejected, turned another way and we finally decided to create a rocking horse in a De Stijl style. At the same time taking consideration of the demands from Playsam and myself.Playsam?s products are archetypes of ordinary objects around us such as the car or the aeroplane. The company mainly produces its toys in wood and the stylized shape together with the blank painted surface has become a hallmark for them.De Stijl, the Dutch art movement containing artists, designers and architects such as Piet Mondrian, Theo van Doesburg and Gerrit Rietveld.
Flygburen laserskanning kopplat till skördarmätning för datainsamling till operativ planering :
The requirements for operative planning activities are increasing. The forest industry wants to gain better control over wood flow. A felling that is more market adjusted is desirable. However, this causes problems in the operative planning process because of the data collection methods used today. Data about timber assortments and data about the distribution of the tree diameter, etc., are often lacking.
Airborne laser scanning is used to a greater extent than before for estimation of forest variables and should perhaps be used to the same extent in operative planning activities as well.
Bakterietillväxt i strömedel till mjölkkor
The resting area is the most important place in the barn for the dairy cow, sometimes called the heart of the free stall system. Inadequate design of the lying area, and lack of or poor quality of bedding materials may reduce the hygiene of the stall. Poor management regarding the cleanliness of the resting area may lead to poor animal hygiene and increased bacterial growth. This in turn will lead to increased risk for environmental mastitis as well as impairing milk quality through contamination with spores.
In this literature study the most commonly used bedding materials; straw, sawdust, wood shavings, clean sand, recycled sand, peat and recycled manure solids, are compared to one another with regards to their ability to resist bacterial growth. Effects of adding hydrated lime to bedding materials have also been studied.
Most bacteria need humidity and prefer a quite high water activity to be able to grow.
Systemanalys av skogsbränsletransporter :
At the end of 70s and the beginning of 80s, 18 terminals was built and used for chipping wood residue from clear cuttings. Most of the terminals was terminated before the 2000s but with the high oil- and energy prices that we can see today there might be a place for these terminals again. The goal with the study was to analyze and compare economical differences between 5 different logistical systems, collected data was used with a set of formulas. The systems include long range transport of slash, chips and bundles. Three of the systems include transport by lorry to industry the last two includes a terminal with access to train transport.
Metoder för att undersöka effekterna av naturvårdshänsynen i skogsbruket efter den nya skogsvårdslagen
Detta arbete har undersökt skillnaderna mellan den nuvarande skogsvårdslagen och den föregående. Undersökningen har bestått av två delar, där ena delen är en litteraturstudie av lagarna och den andra är en fältstudie av metoder för att mäta naturhänsynsförändring. Som komplement till fältstudien har en litteraturstudie av undersökningsparametranas naturvårdsnytta. Litteraturstudien av lagarna gick till på följande sätt, inledningen av båda lagarna och hänsynsparagraferna har lästs och jämförts. Fältstudie har gjorts efter metoder som har arbetats fram och sedan testats i fält.
Stråkröjning och skogsbränsleuttag i unga granbestånd jämfört med konventionella metoder : Två fältstudier vid Asa försökspark
Den här uppsatsen grundar sig på två fältstudier i nyutlagda demonstrationsförsök på Asa försökspark som ska användas i utbildningssyfte. Studie 1 bestod av försöksytor i ett 13 år gammalt bestånd som röjts till samma röjningsförband men med tre skilda metoder; motormanuell selektiv röjning, maskinell stråkröjning och som en kombination av bägge metoderna. Syftet var att beskriva det nuvarande tillståndet, simulera fram prognoser för beståndsutvecklingen och beräkna dess ekonomiska konsekvenser fram till och med första gallring och jämföra de olika metoderna med varandra. Studie 2 bestod av försöksytor i ett 23 år gammalt eftersatt bestånd där fyra olika åtgärder testades; ingen röjning innan gallring, underröjning i samband med gallring, sen röjning och skogsbränsleuttag. Syftet var även här att jämföra de olika metoderna med varandra genom beskrivning av det nuvarande tillståndet, göra prognoser för beståndsutvecklingen och beräkna dess ekonomiska konsekvenser vid första gallring och i den här studien även fram till och med den andra gallringen.
Kommunägd skog i Sverige : en enkät- och intervjustudie av de tätortsnära skogarnas ekonomiska och sociala värde
This Masters thesis is performed at the request of the National Board of Forestry in order to investigate how the Swedish municipalities use their forests. The study is of general character with emphasis on the social values of the forests.
The municipalities? purposes with their forests have varied over time, but lately the social aspects have been recognised as interesting. The social values of the forests can be defined as the values from the forests that contribute to the wealth of humans. This has socio-economic importance for the municipalities.
The study was performed as a quantitative questionnaire survey, complemented with qualitative interviews.
Husväggar av massivträ: En kostnadsjämförelse
Trä är och har sedan länge varit en av Sveriges mest exporterade råvaror. Branschen sysselsätter idag omkring 100 000 människor i landet. I samband med de senaste årens miljödiskussioner bör husens uppbyggnad diskuteras. Syftet med detta examensarbete är att främja husbyggnation i massivträ som de senaste åren fått mer publicitet inte bara på den svenska marknaden men också i centraleuropeiska länder.Frågorna i detta arbete handlar om att identifiera de vanligast förekommande ytterväggskonstruktionerna och jämföra deras materialkostnader samt kostnader för arbete vid montering. För att ha kunnat göra en rättvis jämförelse har BBR?s energikrav varit den gemensamma nämnaren för ytterväggskonstruktionerna.Frågorna har besvarats genom intervjuer med tillverkare av prefabricerade massivträväggar, träregelväggar och betongväggar varpå energiberäkningar utförts i samband med framtagning av olika väggkonstruktioner för att få fram tre lika energieffektiva väggar.
Lättridningens påverkan på hästens rörelsemönster i trav :
The interest in horses and equestrian sport is constantly increasing, and so is the will in both riders and trainers to learn more about the effect the rider and its equipment have on the horse. The last twenty years, more and more studies have been performed were the horse and its kinematics have been in focus. The access to more advanced technology has made it possible to study areas, which earlier have been hard to reach. The knowledge about kinematics in the horse, and how riders and their equipment interact with the horse?s movement, is also of great interest to veterinarians in equine practice.
Markvärdets förändring efter askspridning till skogsmark i Götaland
Askåterföringen på fastmark syftar till att återställa den långsiktiga näringsbalansen och motverka markförsurningen. Den är ett led i ett kretsloppstänkande där allt som tas ifrån marken också ska återföras.Ett ökat behov av skogsbiobränslen leder till att grenar och toppar (GROT) i allt högre utsträckning flyttas från skogen därmed förflyttas en stor del av viktiga näringsämnen. Baskatjonerna som annars motverkar markförsurningen blir kvar i askan.Askan som blir kvar efter förbränning läggs vanligen på deponi, men med hjälp av införda deponiskatter är målsättningen att askan ska återföras till skogen för att sluta kretsloppet.För markvärdesberäkningarna användes värderingsprogrammet Plan33. 12 trädslagsrena fiktiva bestånd skapades, 6 fastmarksbestånd och 6 bestånd på dikad torvmark, med medianboniteter för Götaland.Tillväxteffekterna har visat sig vara måttliga på fastmark. Denna studie visar att endast granmarker ger positivt nuvärde vid askåterföring i Götaland.
Förbättring av U-värde i träkonstruktion för fönster med Aerogel
When constructing a building, a number of aspects must be harmonized in order for it to fulfill requirements ? a building must fulfill requirements such a load-bearing, conservation of energy and a good indoor environment by means of, among other things, moisture proofing .Moisture problems in buildings can affect health negatively. As we are increasingly staying in indoors, demands on a good indoor environment are higher.This work starts with examining moisture problems in slab-on-ground solutions, and then links the various scenarios to moisture problems in a concrete slab of a real building. The building with moisture problems is located in Årby by in Borlänge and moisture damage was found in the slab at an apartment adjoining wall.By reviewing literature written within the field of moisture problem, making hand calculations and modeling in the program Comsol Multiphysics, judgments are made to find explanations as to why the rise of moisture occurred in the building in Årby by.Generally, the following guidelines may be used to reduce the risk of moisture problems in slab-on-ground constructions:Drying of construction moisture before laying the floor material.Using draining layer beneath the slab, to prevent capillary suction.Using insulation under the slab, partly for comfort and to establish the temperature difference between the ground and the concrete slab.Avoid direct contact between the wood and concrete, due to degradation and fouling smells that normally occurs.If necessary, use additional vapor barrier.In addition to the above, there are various methods for moisture-proof and moisture-monitoring by design or by the method ByggaF suited for the entire construction process various events..
Aktiv förvaltning : en utvärdering under volatil tid
Over a long period of time, there has been a rich debate in the academic and financial world if active management can generate an excess return. Many experts say that the current active management strategies is nothing more than a money grab that produces large gains, for banks and investment firms, through high management fees while producing no excess value for the individuals buying their service. In short, an effective market makes it almost impossible for fund managers to produce value for their clients in the long run.No argument has only one side though, other experts say that active management has a role to play because not all investors are rational. This irrationality can lead to mispricing on financial assets in the marketplace and in turn lead to an ineffective market where active management can fill a much needed role. The purpose of this study is therefore to see if active management strategies can create a higher risk adjusted return, taking management fees into consideration, during times of high volatility when the uncertainty is at its peak.