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1207 Uppsatser om Plant composition - Sida 66 av 81
Drainfill
Ocean Thermal Energy Conversion, OTEC, a technology using the temperature difference between cold deep seawater and warm surface water, can extract the work in the form of electricity. OTEC gives also synergies of drinkable fresh water. The temperature difference has an impact on the efficiency of the technology, which means that the feasibility of OTEC is geographically limited. The project intends to explore the possibility of replacing the atoll Tarawa?s present electricity generation with an OTEC plant and to explore synergies. In the present situation all of Tarawa?s electricity is generated by fossil fuels.
- Industrial design engineering study of PCM power plant -
En studie av en mindre kraftstation har gjorts i samarbete med Exencotech som forskar inom energi-återvinning. Deras kraftstation behandlar återvinning av värme från uppvärmt vatten som annars inte hade använts utan ansetts som ren förlust.Den studie som genomförts har gjorts på ett 100kW system med en så stor möjlighet till modularitet som är möjligt för anpassning och flexibel installation. Studien har även innefattat en 5kW prototyp och en modulär version av 100kW systemet upp till 0,5MW. Applikationen har som krav att framför allt minska volymen och storleken på systemet. Studien innefattar även en ergonomisk och användarvänlig inriktning vilket har påverkat designen och konstruktionen hos systemet.För att finna lämpliga lösningar och koncept till projektet har flera konceptgenereringar gjorts, liksom utvärderingar av lösningar.
Modellering, identifikation och reglering av en quadcopter
SUMMARYInventory of raw materials holds an important role in companies within the manufacturingsector. The inventory works as a buffer that secure the supply of materials to the productionunit. The aim of the inventory is to ensure that the company is able to meet the customers?demands despite fluctuations and variations in the material flow. The size of the warehouseand the layout are physical limitations for the quantity of articles that can be stored.
Gudsbilder i svenska visor Fröding/Karlfeldt/Vreeswijk
Charles Hartshorne (1897-2000) was a religious philosopher. He adopted and developed the cosmologic thinking and concept of God from the philosopher Alfred North Whitehead, he was also influenced by Heidegger, Spinoza and other philosophers. According to Whiteheads religious philosophy Hartshorne claimed that there is a dualistic transcendence within the Godhead. A dualistic transcendence where one unity/transcendence of God is abstract, outside the creation and time and therefore is eternal. The other unity (or transcendence) is inside time and creation and closely in process to it .
Uppföljning av plantering på nedlagd åkermark i Skåne 1991-1996 :
The study was performed for the Swedish Regional Forestry Board in Södra Götaland. The study examines broadleaf plantations on former farmland that were planted between 1991 and 1996 with subsidy payments for conversion of farmland into forest. In particular, the study reviews forests planted in 1991-92 and 1994-96.
In the early 1990s, Swedish agriculture was deregulated and direct subsides to farmers ended. The Swedish state instead granted farmers financial support and offered incentives for conversion of farmland and investments in order to make their unproductive land productive.
The state supported conversion of farmland to broadleaf forest, forest for energy biomass production, or establishment of wetlands on former farmland. The County Administrative Boards and Regional Forestry Boards together monitored the planting of broadleaf forests.
Effekter av bearbetningsdjup i plöjningsfri odling
In Sweden, reduced tillage usually means non-inversion tillage, where primary tillage is carried out using chisel ploughs or disc implements. Primary tillage method is mainly determined by the desired soil loosening and the handling of soil residues.
The effect of tillage depth was studied in field experiments in Skåne, Väderstad, Uppsala, Örebro och Västerås in different crops; spring oilseed rape, spring wheat, winter wheat and spring barley.The experiments generally had a randomized block design with the treatments mouldboard ploughing, deep chisel ploughing and shallow chisel ploughing, in some cases also shallow discing and no-tillage. In the experiments the following parameters were determined: seedbed properties, saturated hydraulic conductivity, penetration resistance, number of emerged plants and crop yield (all parameters were not determined in all experiments. Root growth and draught requirement were determined in two separate studies.
There were no significant differences between tillage depths in non-inversion tillage in seedbed properties, plant emergence or root development.
Laserskärning i Sverige : ? tekniken, marknaden och hur de utvecklas
Laser for material processing possesses a number of advantages which mean that it has been and will be an important component for a wide range of industries' future development. Cutting materials processing is the dominant use of laser technology and has revolutionized the manufacturing industry. The aim of this thesis is to describe the principles of metal cutting by laser, how laser cutting is applied in practice and to identify how Swedish companies are using laser cutting. For the theoretical and technical description of laser cutting literature studies are the primary source of information. The empirical basis for the mapping of the Swedish industry for laser cutting is grounded on a survey; this includes Swedish companies that use laser cutting in their production.
Effektivisering av råvarulager för lagerhållning av ett bredare artikelsortiment
SUMMARYInventory of raw materials holds an important role in companies within the manufacturingsector. The inventory works as a buffer that secure the supply of materials to the productionunit. The aim of the inventory is to ensure that the company is able to meet the customers?demands despite fluctuations and variations in the material flow. The size of the warehouseand the layout are physical limitations for the quantity of articles that can be stored.
Trängselskatt En jämförelse av systemet i Göteborg och Stockholm
SUMMARYInventory of raw materials holds an important role in companies within the manufacturingsector. The inventory works as a buffer that secure the supply of materials to the productionunit. The aim of the inventory is to ensure that the company is able to meet the customers?demands despite fluctuations and variations in the material flow. The size of the warehouseand the layout are physical limitations for the quantity of articles that can be stored.
Reducering av produktionstryck i A-linan : Förflyttning av produkt
In the production of pulp, paper and cardboard, a large amount of water is used daily. The water has to be purified in the internal purifying plant before it reaches the receiving body of water. In the biological purifying stage at the Stora Enso Skoghall mill, an aerated basin is used where the microorganisms, using oxygen, oxidize the organic material to carbon dioxide. The air is pumped from the bottom of the basin and the oxygen can then be transported from the air bubbles to the water through diffusion. The problem with aeration of waste water from the forest industry is that wood residues, such as fatty acids, are making the transport of oxygen in water more difficult.
Den bäcknära zonen vid små skogliga vattendrag i Värmland : generell beskrivning, förekomst av traktorspår samt kvicksilverhalter i körpåverkat ytvatten
Forest streams and the associated riparian zones are sensitive to disturbances and changes that occur within these riparian areas. Particularly sensitive are small streams of low order, which will have large impacts down-stream. The disturbances that occur in the riparian zones are reflected quickly in the stream. Driving with forestry machines in the riparian zone will have detrimental effects to the soil and water. Driving the machines will lead to changes in the mineral soil composition, resulting in the reduction of porosity, less infiltration, compaction, and an increased bulk density.
Små skogliga vattendrag i Värmland - Generell beskrivning, förekomst av traktorspår samt spårens inverkan på bottenfaunan :
Modern forestry requires a high degree of machine traffic for clear felling and scarification operations. The machines most frequently used are big and the traffic often results in tracks on the forest ground. There are many small streams running through a forest, in connection to logging operations, machines might cross these frequently. These crossings could result in the erosion of fine particulate inorganic matter, which ends up in the stream. The aim of this thesis was to give a general description of small forest streams of order-one in the county of Värmland and to determine the frequency of machine tracks in small streams.
Produktion av Pyrolysolja från kvistrejekt
Fast pyrolysis is a method for converting biomass into three energy rich products: char, gas and bio-oil, where the latter is most interesting. Pyrolysis is an endothermic process where biomass is heated in an anaerobic environment and, with the right operating conditions, up to 80 %wt bio-oil can be extracted. Key parameters for fast pyrolysis are: stable reactor temperature (~500°C), short residue time for gas in the reactor (<2 s) and a very high heating rate for the biomass. Today there are several different process solutions for fast pyrolysis, where fluidized beds and rotating cones are most developed. Bio-oil has compared to fossil oil: lower heating value, low pH and also polymerizes with time. Because of this upgrading is desirable for increasing competitiveness.
Validering av metoder för analys av Cu, Fe och Na i processvatten med AAS-grafitugn
Södra Cell Mörrum is one of the five paper pulp plants that are included in Södra Cell, and the paper pulp that is produced here is not only sold to Swedish paper mills. Most of the paper pulp is exported to different countries in Europe. In the manufacturing process the plant needs different kind of process water and there are guideline values for how much copper, iron and sodium this water is allowed to contain. Analyzes of this water is in the current situation done with an atomic absorption spectrometric instrument (AAS-instrument) with a flame. Measurements done with flame-AAS of samples that have concentrations near the guideline values for copper, iron and sodium, are not reliable. The reason for not being reliable is that the quantitation limits of these metals are higher than the limit values.
Släntstabilitet för sluttäckningen av avfallsdeponin i Holkesmossen, Hagfors kommun: Stabilitetsberäkningar och rekommendationer för fortsatta arbeten
Återvinningsstation Holkesmossen ligger cirka två kilometer öster om Hagfors i Värmland. Deponiverksamhet påbörjades på platsen under 1960-talet, och fortsätter fortfarande.Tidigare forskningsprojekt vid Luleå tekniska universitet har, tillsammans med Hagfors kommun och Uddeholms AB, tagit fram en design för sluttäckningen av avfallsdeponin. I denna lösning används restprodukter ifrån det lokala stålverket tillsammans med konventionella jordar.Delar av deponin började sluttäckas år 2005. I dagsläget pågår sluttäckning av deponins norra slänt. Arbetet utförs etappvis och i takt med att de slaggmaterial som används till tätskiktet har producerats och finns tillgängliga.I denna rapport har släntstabiliteten för sluttäckningen utvärderats.