Sökresultat:
662 Uppsatser om 3 dimensional wood composite - Sida 1 av 45
Epoxidised linseed oil as hydrophobic substance for wood protection : technology of treatment and properties of modified wood
Public concern about the release of toxic compounds from wood-based products drives legislation towards enforcing industries to find and use more sustainable solutions for wood treatment. Plant oils are good alternatives to treat wood, minimizing or even neutralizing the impact on the environment. Wood modification with epoxidised linseed oil (ELO) and acetic acid as catalyst has proven a suitable method to impregnate and protect wood. However, the mixture presents a serious inconvenience because of the quick polymerization of the ingredients that limits its practical application. Therefore, this study was designed to evaluate an alternative method using a two-step process which bypassed the problem above.
Utredning om andra tillämpningar än byggstommar för profilpressade träkompositer av OSB-material.
Newbeam Sweden AB är ett ganska ungt företag som genom deras patent har börjat kunna pressa unika träkompositer i 3 dimensioner. Företaget ligger i startgroparna med sin första tillverkningslina som skall öppnas i Söderhamn, Hälsingland.De själva har satsat mycket mot byggnadsindustrin. Min uppgift i detta arbete har varit att undersöka andra marknader med deras profi lpressade träkompositer som grund. Inriktningen blev butiksinredningar som ett resultat av researcharbetet som gjordes.Intervjuer och undersökningar gav en bild av hur viktigt det är med användarvänlighet samt enkelhet och de två orden blev mitt motto arbetet igenom.Resultatet av detta kom att bli lite mer än bara butiksinredningar..
Trä och fukt ? Mätmetoder för fuktrelaterade dimensionsförändringar hos trä och deras användbarhet, med två fallstudier inom konservering
This thesis deals with different methods for measuring moisture-related dimensional changes ofwood. Typically relative humidity is measured to determine if the ambient climate around anobject is harmful to it or not. Values between 40 to 65% RH are recommended for hygroscopicmaterials. To know how a wooden object actually reacts to changes in the surroundingenvironment requires methods that involve the object itself. Because of the wood anisotropy,differences in wood structure, finishes and other restraints, it is not always possible to predict themovements.This paper addresses various measurement methods, primarily methods that have been testedin the field of conservation, with examples of their use.
Implementering av 1D-DCT
IDCT (Inverse Discrete Cosine Transform) is a common algorithm being used with image and sound decompression. The algorithm is a Fourier related transform which can occur in many different types like, one-dimensional, two-dimensional, three-dimensional and many more.The goal with this thesis is to create a fast and low effect version of two-dimensional IDCT algorithm, where techniques as multiple-constant multiplication and subexpression sharing plus bit-serial and bit-parallel arithmetic are used.The result is a hardware implementation with power consumption at 19,56 mW..
Tvådimensionella rum
We are always surrounded by space, not just only in a room with four walls, but also when we are outdoors.Constantly we move in a flow of space that changes whenever we move. Unaware we are affectedby this threedimensional surrounding of ours, and it reacts with our perception. Many times, we chooseto translate it into something two-dimensional, for example when we take a photo, recording a movie orframing a view with a window. It helps us to catch a moment, a piece of reality and restore it in our ownway. In this project I?ve chosen to explore this process, to interpret and create my own theories about thistranslation from space to a two-dimensional surface.
Dimensioner. Mellan 2D och 3D, en undersökning av yta och innehåll
A project exploring the boundaries between 2D and 3D. What is surface and what is substance? A countinuation of previous projects where I?ve examined the journey from two dimensional paper to three dimensonal objects. This project deals with the journey from three dimensonality back into a flat two dimensional surface, and the question if something can be both 2D and 3D at the same time. I decided not to center the project around a specific item, but rather let the project itself be in focus.
Förskollärare och barnskötare : yrkesroller i förändring
Syfte: Syftet med denna studie var att se hur och varför volatiliteten påverkades i DJIA, S&P 500 och NASDAQ Composite under IT-bubblan.Metod: Års- och månadsvolatiliteten för DJIA, S&P 500 och NASDAQ Composite har beräknats under 1995-2004 med hjälp av data från Yahoo Finance.Empiri: Resultatet visar att volatiliteten var väsentligt högre i NASDAQ Composite än vad den var i S&P 500 och DJIA som i sin tur höll en liknande volatilitet i förhållande till varandra.Analys: I analysen framträdde det att volatiliteten blev väsentligt högre i samband med att bubblan sprack under maj 2000 fram till dess att paniken lade sig kort efter maj 2002. Det fanns en hög överensstämmelse mellan denna rapport och övriga tidigare studier. Teorierna var mestadels väl applicerbara.Slutsats: Volatiliteten för DJIA, S&P 500 och NASDAQ Composite var som högst mellan 2000 och 2002 under undersökningsperioden 1995-2004. IT-bubblan uppstod samt sprack till följd av irrationellt investeringsbeteende bland investerarna på aktiemarknaden och paniken som uppstod efteråt gjorde att volatiliteten på aktiemarknaden höll sig förhållandevis hög fram tills den lade sig kort efter maj 2002. NASDAQ Composite hade högst volatilitet till följd av IT-bubblan medan DJIA och S&P 500 hade likvärdig volatilitet.
IT-bubblans inverkan på den amerikanska aktiemarknadens volatilitet
Syfte: Syftet med denna studie var att se hur och varför volatiliteten påverkades i DJIA, S&P 500 och NASDAQ Composite under IT-bubblan.Metod: Års- och månadsvolatiliteten för DJIA, S&P 500 och NASDAQ Composite har beräknats under 1995-2004 med hjälp av data från Yahoo Finance.Empiri: Resultatet visar att volatiliteten var väsentligt högre i NASDAQ Composite än vad den var i S&P 500 och DJIA som i sin tur höll en liknande volatilitet i förhållande till varandra.Analys: I analysen framträdde det att volatiliteten blev väsentligt högre i samband med att bubblan sprack under maj 2000 fram till dess att paniken lade sig kort efter maj 2002. Det fanns en hög överensstämmelse mellan denna rapport och övriga tidigare studier. Teorierna var mestadels väl applicerbara.Slutsats: Volatiliteten för DJIA, S&P 500 och NASDAQ Composite var som högst mellan 2000 och 2002 under undersökningsperioden 1995-2004. IT-bubblan uppstod samt sprack till följd av irrationellt investeringsbeteende bland investerarna på aktiemarknaden och paniken som uppstod efteråt gjorde att volatiliteten på aktiemarknaden höll sig förhållandevis hög fram tills den lade sig kort efter maj 2002. NASDAQ Composite hade högst volatilitet till följd av IT-bubblan medan DJIA och S&P 500 hade likvärdig volatilitet.
Celltal som mått på mjölkens kvalitet med avseende på mjölkens sammansättning
Mastitis, an inflammation of the udder mainly caused by a bacterial infection, induces an increase in the somatic cell count (SCC) in milk and is consequently one of several factors affecting SCC in milk. In this literature review it is investigated whether SCC; on udder quarter, cow composite or bulk tank milk level, can be used as a quality marker with focus on milk composition in terms of the content of fat, lactose, total protein, casein and whey protein. According to this literature review the relation between SCC and milk composition is not reliable either on udder quarter, cow composite or bulk tank milk level. SCC was related to lactose, casein and whey protein on udder quarter level; lactose and whey protein on cow composite level and lactose on bulk tank milk level.
Sequi : Tredimensionell sequencer
Music production software has a strong tradition of two-dimensional graphical user interface (GUI), in which the time line is represented as a flat composition either horizontally (from left to right) or vertically (from top to bottom). In my degree work titled Sequi, I approach music composition from a different angle. Instead of a two-dimensional time line with only two possibly ways of progression (forward or backward) I constructed a three-dimensional GUI with the maximum of four different ways of progression from any given point in a composition. The height axis is used to describe time-intervals (the time between downbeats) and the wide and depth axes are used to describe progression from one sound to another..
FE-modellering av hjullast på sandwichpanel
This bachelor thesis in mechanical engineering was performed during the spring2015 in collaboration with Composite Consulting Group in Laholm. TheComposites Consulting Group works mainly with design and details of differentcomposite projects, their main area is FE-calculations, 3D-modelling andmechanical tests with composite materials.The aim of this bachelor thesis was to simplify the calculation process of solidmechanics for sandwich panels by simulation with computer software. The goalwas to decrease the time for the design and calculation process of the constructionand the cost of the practical tests. Our task was to build a static three dimensionalmodel with the computer software Abaqus, where the result should correspondwith the practical pressure tests in laboratory.The project started with collection of material data from Composites ConsultingGroup and by learning the software Abaqus, simultaneously a specification wasdeveloped in corporation with the company. Later on, a static wheel pressuremodel in the software Abaqus was produced which simulated the behavior of thesandwich panel during static wheel-pressure by a pallet truck.
Effekt på värdeutfallet av sågad vara vid övergång från 30 till 60 cm moduler : - en fallstudie av Moelven
The purpose of this study is to explain how the value of sawn wood changes when sawn wood are cut in 30 respective 60 cm lengths. The raw material into the saw mill will mainly be bucked in 30cm and 60 cm modules. There will also be two alternatives where the timber will be bucked special lengths, 370, 490 and 550 cm but also in 490 and 550 cm.The method used for the study is to simulate both cutting and sawing the woods. For cutting the simulator Timan is used and for sawing the simulator Timberopt is used. When data is generatedfrom the simulators, calculations of some key figures is done and also how much the revenue need to be increased for the sawn wood in order to cover for the increased costs of changing sawn woodfrom 30 cm to 60 cm modulesThe conclusion is that the single biggest reason, impacting the value of the sawn wood is the cutting at the saw mill.When going from 30 to 60 cm modules, the impact will be that the customers to the saw mill must pay more to increase the revenue by at least 10% for the sawn wood in order to justifice the changein production.It is also possible to increase the value of the products further by bucking the timber in three lengths, 370, 490 and 550 cm, in order to get 12 % increase of the share of longer sawn wood (>= 480 cm)..
Skogsbrandens påverkan på död ved :
Fire is an important ecological factor, but its consumption of coarse woody debris, CWD, has hardly received any attention. In this study, I investigate the consumption in relation to the time of initial flame exposure and propensity for continued combustion of standing CWD of pine (Pinus sylvestris).
Two types of CWD were studied. Firstly, wood that had been dead for one to ten years. Secondly, wood that had been dead for several decades. In the burning experiments, logs of approx.
Trä som fasadmaterial ? behandling och beständighet
Since prehistoric time man has used wood to build their environment. The material?s availabilitycombined with its good mechanical properties has often made it the material of choice. Like allmaterials exposed to natures degradative processes the properties of wood decreases over time.Rot, UV radiation and attacks by insects and pests damage wood if not protected. Since we wantwhat we build to consist, optimizing our building materials durability is of great interest.Techniques and methods for increasing the endurance of wood have been developed in severaldifferent places and for a long time.
Visuell handelsortering av furu och gran
This essay concerns the visual trade grading of pine and spruce.In the 1800s developed rules for sorting of wood. The rules used to facilitate the export trade.The terms of the regulatory sorting systems developed in the 1900s. While it still used some of the older terms.The essay deals with how the grading rules affect the use of wood and how the rule work and how the terminology works.Some of the terms used for sorting are O/S, Kvinta, Utskott and A,B,C,D.You sorting by counting the numbers of knots, cracks and other characteristics of each piece of wood.The sawmills have much influence in how the rules developed.Today it is often already determined in the sawmills which uses each piece of wood most have..