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A field experiment was carried out in 2006 to investigate the effects of deep rotary cultivation on sugarbeet growth. The background to the experiment was a 2005 study showing potentially higher yield, higher cleanness and higher sugar content when primary tillage was carried out to 35 cm depth with a rotary cultivator.
On four field sites in Skåne (L:a Isie, Ädelholm, Stävie and Vragerup), five different
treatments were compared: mouldboard ploughing in the autumn to 20 cm; mouldboard
ploughing in the autumn to 20 cm + rotary cultivation in the spring to 35 cm; rotary
cultivation in the autumn to 35 cm; rotary cultivation in the spring to 35 cm; and mouldboard ploughing in the spring to 20 cm.
The rotary cultivator used in the treatments is manufactured by a Dutch company, Imants. The implement cultivates the soil with spade tines fitted on arms that are mounted on a horizontal rotating PTO-driven axle.
Beet plants were inspected and yield determined in the experiment, and three soil parameters were examined: penetration resistance, water infiltration and infiltration of blue dye. Root shape was also examined.
The site at Stävie was not harvested due to poor beet establishment. At the other sites, the highest yield was found when the soil was rotary-cultivated in the autumn.
LCC-analys av FTX-system : En jämförelse av centralt- och lägenhetsplacerat
This report is the result of a thesis conducted at the consulting firm Bjerking AB andis the final part of the Bachelor Programme in Construction Engineering at Universityof Uppsala. The work aims to investigate the costs and how the choice of ventilationsystem affects building projects during a long-term period. This report covers costssuch as investment, maintenance and energy but also how they affect residents andbuilders. Building regulations for energy consumption are expected to be tougher;therefore a comparison of two different heat recovery ventilation systems(HRV-system) was made. One system is based on a centrally placed unit that coversthe whole buildings ventilation through vertical shafts.
Applikationsutveckling med nätverkstrafikfunktioner : En jämförelse av tre mobilplattformar avseende nätverkstrafikfunktioner
The objective of this study was to examine three common mobile phoneplatforms in relation to their network traffic features. The platforms to beexamined are Android, iOS 5 and Windows Phone. After the investigation wascompleted a prototype application was implemented in order to demonstratethese features in the most suitable platform. The application will function as atelephone call exchanger. In addition, the application must also send the userstatistic to a Web server, accept contacts from a Web server, as well as having aspecial administration part in which the userstatistc can be presented.
Infallsvinklar och angreppssa?tt fo?r en svensk livsmedelsstrategi : En utredning av angreppspunkter och betraktelsesa?tt hos livsmedelsstrategi-intressenter samt ha?llbarhetsaspekter av dessa.
Understensho?jden is Stockholm's largest eco-village which was built in the early 1990s with the vision of enabling ecological living for people. However the ecovillage is no longer considered as environmentally friendly because of its relatively high energy consumption, and non-updated energy system. The purpose of this study is therefore to investigate how Understensho?jden should reduce their energy consumption and upgrade its energy system by using Blower-Door, IR-camera and Design Builder.
Förrotation till omrörare
The primary function of a mixer is to keep a fluid in constant motion. All mixing applicationsrequire varying degrees of small-scale turbulence and bulk flow. The performance of asubmersible mixer is measured by the thrust that it produces, while the strength of the bulkflow is dependent on the total amount of installed thrust.In a mixer, the fluid quickly flows past the propeller, and as a result, the current is mainlyaxial. The fluid will also obtain a rotating velocity, or a swirl, though this is significantly lessthan that of the propeller. During the process, the total amount of energy increases in the formof static pressure and kinetic energy.
Innovativ utmatningsteknik : Mediumstor bulkförvaringslösning
This master thesis was done for a company called BRUKS which is active in woodprocessing,bio-energy and bulk material handling industry. The idea for the master thesis wasto develop a new reclaiming method for silos where wood chips are being stored. A mediumsegment of between 1000 ? 5000 m3was defined as the segment with the most sales potential.Two different concepts were produced, one for new constructions and one for rebuildingalready existing silos.In the beginning of the master thesis a lot of time was spent on visiting different BRUKSoffices and customers to get an overview of the industry and the product. This informationwas the basis when the idea generating phase began.
Understensho?jdens framtida utveckling : ett arbete om energieffektiviseringar i ekobyn samt uppgraderingar av dess energisystem utifra?n ett ha?llbart perspektiv
Understensho?jden is Stockholm's largest eco-village which was built in the early 1990s with the vision of enabling ecological living for people. However the ecovillage is no longer considered as environmentally friendly because of its relatively high energy consumption, and non-updated energy system. The purpose of this study is therefore to investigate how Understensho?jden should reduce their energy consumption and upgrade its energy system by using Blower-Door, IR-camera and Design Builder.
Livscykelanalys av flerbostadshus ? energieffektiviseringsåtgärder för minskade koldioxidutsläpp
The importance of energy- and environmental issues has increased, and the work towards reducing carbon dioxide emissions plays a major part. The European Union has set up goals for the membership countries to work towards this to happen. The carbon dioxide emissions in Sweden have been reduced the last few years, but there is still a lot to do. About 30 per cent of Sweden?s carbon dioxide emissions generate from energy usage related to housing, this is why the housing sector is of interest to examine.
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.
Utbrändhet bland svenska alpina tränare, finns det? : Vad ska kunna göras för att förbättra tränares arbetssituation?
Aim: The purpose with this study was to examine if there is burnout or symptoms of burnout among Swedish alpine coaches. The study would also investigate if the place of work have any meaning of developing burnout symptom or to become burnout. How the coaches think that their working situation could be any better is also going to be lightened.Method: The participants in this study were all full time paid alpine coaches in Sweden. Total amount of participator was 28. 13 of them worked on ski gymnasium, 4 worked on ski collage and 11 worked in SSF (Swedish Ski Federation).
Underlag för bedömning av energibrunnar inom vattenskyddsområde
Denna rapport beskriver arbetet med utvecklingen av en ny modell för kaplanturbiner. Utvecklingen bygger på två kopplade differentialekvationer som under arbetets gång anpassats och implementerats i turbinmodellen.Modellen beskriver hur vattenflöde och turbinmoment påverkas av avvikelsen från den optimala kombineringskurvan för vinklarna på turbinens ledskena och löphjul, och är anpassad för ett referensaggregat med tillgängliga provdata. Även övriga enheter i vattenkraftaggregatet modelleras och sätts samman med frekvensregulator och elnät för att simulera aggregatets reglerstabilitet i önätsdrift.Verifieringen av turbinmodellen sker genom försök att återskapa de befintliga verkningsgradskurvorna med hjälp av modellen. Resultatet visar en god följning av de verkliga kurvformerna, dock med något lägre maximal verkningsgrad.Verifieringen av önätmodellen sker genom att prova stabiliteten i nätfrekvens och turbineffekt vid stegpålastningar. Resultatet ger en stabilare reglerstabilitet än i verkligheten, men uppfyller ändå förväntningarna på en fungerande modell.This report describes the development of a new kaplan turbine model.
Smarta lokala energisystem, Vision-Teknik-Tillämpning
The energy sector is facing an impending paradigm shift. Today?s technology enables the end-user to generate their own energy locally at home. Furthermore, recently developed storage technologies make it possible to balance energy demand with stored energy and integrate district heating with the local power grid. This means that in the future heat and electric power will interact and energy flows is converted over energy boundaries.
Effektmätning i pump
The interest for power and energy measurement has greatly raised with todays increasing electricity prices and enviromental awareness. In the search for energy efficient solutions, the measurements are more complex due to increasing of non linear components. Harmonics and non sinusoidal voltages put high demands on sampling and filtering. Meanwhile, the price must be controlled so the customer still will find it interesting to invest in smaller plants. ITT W&WW asks for a robust, heat resistant power meter with compact dimensions to allow mounting inside the casing of a pump.
Utvärdering av energieffektiviseringsåtgärder på Bokelundskolan i Växjö
The purpose with this report is to examine how the implemented energy efficiency measures on Bokelundskolan in Växjö have had impact on the energy use. The measures which have been implemented are, new ventilation system, new heating system, optimized adjustment of the heating system, new windows with U-value 1.2 and lower window height, insulation under windows and in the crawl space. The school's energy use before and after rebuilding has been calculated with the calculation program, Vip-Energy 1.5.5.Calculations of energy use for the school with windows on U-value, 0.9 and 0.7 have also been done. The replacement of windows has been studied from a cost perspective. The conclusion is that the exchange of heat and ventilation system was the biggest contributor to reduced energy use on Bokelundskolan.
Solenergi på Kvarnholmen
In recent years it has become more and more evident that man has contributed to much of the climate changes that have taken place during the last century. A major challenge today is to reduce emissions and energy usage at the same time as the global population is growing. To contribute to a better environment, Stockholms Stad has set at target of becoming fossil fuel free by the year of 2050. The construction of new districts is done with this goal in mind; energy efficiency and renewable energy sources are examples of methods to achieve this.Solar energy is considered to be a sustainable energy source and the most common techniques to harvest solar energy in Sweden are solar cells and solar collectors which produce electricity and heat respectively. This report aims to investigate whether an investment in any of these systems would prove to be economically beneficial at Kvarnholmen, a district under construction in eastern Nacka, Stockholm.Since the finished blueprints only cover a small portion of Kvarnholmen, the report examines the possibilities for a house where construction has already begun, Nya Kvarnen.