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1177 Uppsatser om Forest fuel - Sida 25 av 79
Bränsleövergångar : Miljölagstiftningarnas inverkan på fartygsdriften
Under vårt sista år var vi intresserade av att ta reda på de problem som vi kan stöta på i våra yrkesroller som fartygsingenjörer. Arbetet tar upp de tekniska problem som uppstår p.g.a. de allt strängare kraven på minskade svavelutsläpp från fartyg. De tekniska problemen härstammar från de olika bränslekvaliteternas vitt skilda egenskaper. Som svar på dessa problem har det utvecklats tekniska lösningar varav två stycken har tagits upp i detta arbete.För att ta reda på vilka tekniska problem som kan uppstå tog vi del av den berörda utrustningens tillverkares erfarenheter enligt empirisk modell.
Lost World : Home of the seven and a half legged tree
The main focus for this essay is to describe the relationship between human and nature through a material investigation that takes its shape through sculpture. With the help of a fairytale-like story the reader can share the creation of the sculpture and how my thoughts flow through the process that will result in an exam project. Rooted in earlier projects I discuss the crash between civilization and the wilderness as well as talking about the likeness of the creative process and child play. I also discuss the body's place in the forest and the loneliness that we humans created that has cut us off from the rest of the creatures and plants in the forest. My aim is that in the final piece I will create a fiction place where these can be joined together again.
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.
GROT-transport från norra till södra Sverige
The European Council agreed in 2008 on a climate and energy package to combat global warming. This package is valid for each EU member country and means that greenhouse gas emissions must fall by at least 20% and the EU's energy use to 20%, consisting of Renewable Energy in 2020. The Swedish Government has set stringent climate and energy with the intention to set an example for the rest of Europe. For example, renewable energy sources account for at least 50% of energy use and our climate emissions to fall by 40% by 2020. A combination of these goals and a steadily rising oil price has led to an increased demand for wood fuel in the form of such branches and tops.
Kvantifiering av osäkerheter i lyftkraftsmodellen
With today´s power uprates in BWR reactors the bundle lift force has become aproblem. The lift force is calculated using a best estimate approach and the resultfrom the calculation should pass the existing lift force margin. Lift force margin isdefined so that the lift force may not exceed 80 % of the fuel weight. The margin issupposed to cover all the uncertainties that exist in the lift force calculations.However, no uncertainty analysis has been conducted to quantify the uncertainties.In this report the uncertainties in the lift force model have been quantified. Each inputparameter to the lift force model which has been assumed to have an uncertainty isassigned a probability distribution.
Lönsamhet i att avverka virkesrik fastighet innan försäljning
The purpose of this study is to find out the viability in performing final felling in stands with high timber volume or if it´s more profitable to leave these stands to the next owner. Will he or she pay more for the standing stock then the industry? The prices of forest-land have increased significantly over the last couple of years in Sweden and some properties seem to go higher than others. Is this because of higher standing stock volume or can a certain volume/hectare bring a higher price? Maybe a combination of both? This study is based on the the sale-statistics for 2012 from real-estate agency Areal.
Markägare i Stockholms län och deras inställning till biodiversitet och skydd av mark :
This report investigates what attitude private forest owners in the County of Stockholm,
Sweden have towards biodiversity landconservation. Private landowners were asked to
answer a questionnaire containing questions about there property and there attitude towards biodiversity. The results show that private landowners attitude towards biodiversity is affected by, amongst other things, the size of their property; a larger property have a more negative owner than a smaller property. A landowner that lives on his property has a more negative attitude towards biodiversity than a landowner that?s not living on his property.
Detaljhänsyn efter slutavverkning : kvantitet och inverkan på framtida produktion hos SCA i Västerbotten
According to FSC (Forest Stewardship Council) shall at least a mean of 10 trees per hectare including riparian zones and other areas with high biological values be left in final felling. In addition large clear areas should not be created and all retained trees with high environmental value shall be spared. To leave trees in final felling means a lower cutting volume and hence a lower income from the cutting, but it also means that the production in the next generation becomes less because of competition. The aim of this study was to evaluate the effect retained trees have on the production in the new generation of forest, and to investigate if there is any way to lower this effect. The environmental care has also been estimated by the amount left in final felling.
Etanolmarknaden i Brasilien : etanol som fordonsbränsle
According to the EC fuel regulations 2 % bio fuel has to be blended in all fuel by the year 2005, and 5.75 % by the year 2010, which means ethanol for gasoline driven vehicles, so there will be a substantial demand for ethanol. Brazil already has an established industry for producing ethanol and is the leading producer and exporter of fuel ethanol. My purpose with this paper is to investigate why Brazil decided to develop ethanol production on a large-scale operation and to find out today?s situation. Focus will mainly be on ethanol production with sugarcane as a feedstock.
En jämförande studie av fluiddynamiken för olika fluidiseringsmedium i en kallmodell av en 100 kW-anläggning för kemcyklisk förbränning
To reduce emissions of carbon dioxide (CO2) Carbon Capture and Storage (CCS) technologieshave been developed. Chemical Looping Combustion (CLC) is a CO2 capture technologywith the CCS framework, and at Chalmers University of Technology in Gothenburg,Sweden, a 100 kW chemical looping combustor has been built.This project aimed to investigate to what degree air can replace helium as the uidizinggas for uid dynamical studies in a CLC cold ow model of the above mentioned 100 kWfacility. Experiments were performed using air and helium separately as uidizing gas andpressure data were obtained, which formed the basis for the comparison. The project alsoaimed to investigate uid dynamics in the uidized bed and study when the risk of sluggingoccuring was greatest. The results were presented in the form of figures and tables dividedinto pressure, concentration and standard deviation of the pressure.The results obtained showed that air as uidizing gas did not create the same uid dynamicsas helium over the entire fuel reactor.
Miljödifferentierad fastighetsskatt
It is essential to reuse- and recycles residues to decrease the amount of deposit materials and reach sustainable energy use. Two ways to work towards this is to recycle wood ashes to the forest as nutrient compensation and extract biogas from combustion of biomass.The aim with this study was to decide whether wood ashes that been used for biogas upgrading with accelerated carbonation also can be used as a nutrient compensation in the woods according to recommendations from the Swedish Forest Agency (Skogsstyrelsen).The ashes that were used in this study came from Johan Andersson who works at JTI in Uppsala, who also treated the ashes with biogas. The ashes have, in both untreated and treated condition, been analyzed in this study according to contents of elements, leaching properties, hardening properties and contents of crystalline phases, to evaluate what impact carbonation with biogas has on the ashes.The accelerated carbonation led to hardening of the ash, and decreased amount of CaO- and increased amount of CaCO3. The CO2-uptake also entails a dilution of the elements, and the content of nutrients and trace elements decreases. However the results show an indication of an uptake of S from the biogas to the ash, since the dilution had a smaller impact on S than the rest of the elements.
The major food trees of the Angola black-andwhitecolobus (Colobus angolensis palliatus)in Diani Forest, Kenya
The Angola black-and-white colobus (Colobus angolensis palliatus) is a subspecies of Colobus angolensis inhabiting fragmented forests in coastal Kenya and Tanzania. C. angolensis is regarded as Least Concern in the red list of IUCN because its populations are abundant. However, the populations of C. a.
Natur som kultur : och betydelsen av dess berättelser
Is there such a thing as unadulterated nature? All that surrounds us is culturally modified by man somewhere along our past. But culture is only a fictitious conception itself, created in an attempt to break the world into controllable objects.So in what do we find culture? In everything? In the objects or the stories they embrace? Who chooses what?s worth saving and how to save? Choosing what is culture is made from personal, ingrained dichotomies of what?s important and what is not. A selective eye creates a distorted truth, which could have unintentional long-term effects.This thesis will give a historical account of the archaeological discipline?s development in tending to our cultural heritage.
Mobilt internet för skogsbruket med CDMA2000 i450 MHz - bandet :
Improved wireless datacommunication with the forest machines might be the next big step in the logging process. The use for wireless communicationsystems within the forestry is among other things to report the production from the forest machines, to supply the machine opera-tors with the right information and for safety. CDMA2000/ 450 is a third generation mobilecommunicationsystem which could replace the old NMT- 450 and for comparatively low costs. The reason for the low costs is that you only have to use the old NMT- 450 masts and supply them with new equipment. In the test of CDMA2000/450, that has taken place in northern Uppland, two kind of files have been sent.
Volymsrapportering vid terrängtransport av virke
This report is a B.Sc. Forestry thesis work at the school for Forest Management, SLU.
The work was an assignment from the forest owners? association Mellanskog.
The aim of the work where to investigate the economical result of removing undergrowth trees before first thinning, and a follow-up of the contractors and their compliance with Mellanskog standards.
This thesis work was divided in three parts: The first was to find a relation between the net volume from the first thinning and the cost of cleaning undergrowth trees. Secondly there was a follow-up in the field, to investigate whether the contractors have done the undergrowth cleaning according to Mellanskog?s directives.