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293 Uppsatser om Crop rotation - Sida 14 av 20
Konstruktion av säkerhetslagerför svänghjul
This thesis is the result of the investigation and solution of a mechanicalproblem regarding flywheel malfunctions. A flywheel is, in short, a devicethat relies on a rotating object?s moment of inertia to store energy overshort time spans. This project is part of the development of a fourthflywheel prototype at the division for electricity at Uppsala university,which uses magnetic levitation to keep a hollow cylinder rotating at veryhigh speeds inside a vacuum chamber. Should the magnets fail however, orsome other error occur that leads to an uncontrolled state of rotation, thecylinder needs to be stabilized mechanically by a device usually referredto as ?back-up bearing?.
Igensättning av övre spalten i centrifugalpump
This report focuses on the upper slit. The upper slit is located between the impeller andthe drive unit. The slit design depends on pump type and application. However it isuncertain why the design varies, The purpose of this report is to clarify why the designvaries and to recommend an improved slit design.A research has been done; information was gathered from interviews, but also fromsearching of databases and studies of drawings, reports and documents. The originalpurpose of the slit was to prevent twining around the driveshaft, and prevent dirt fromentering the cooling system.
Kostnader för jordbearbetning och sådd :
Syftet med detta examensarbete är att sammanställa maskinkostnader för etableringsmetoderna plöjningsfritt och konventionellt. Vi vill även titta på hur stor kapacitet som behövs på maskinparken för den tänkta gården på 600 ha åker, detta för att hinna etablera grödan inom ett rimligt tidsspektra. Anledningen till att vi valt ett företag på 600 ha är att det är den areal tröskan klarar av att avverka inom rimlig tid. Det medför att vi måste ta en del hänsyn till lägligheten och hur mycket av tiden som är så kallat ?tjänligt väder?.
Flexible Snowboard System
The project, Flexible Snowboard System, has been carried out by the project group independently and is a module developed for snowboarders, ski rentals and ski schools. The problems of today?s solutions are that they cause the user an inconvenient standing position when riding the ski lift or skating the transportation slope, also mounting, adjustments and disassembling of the bindings are time consuming and brings undesired wear to the screws and screw holes. In addition any adjustments require that the user steps out of the bindings and have tools at hand. Flexible Snowboard System is a universal module which means that it can be assembled with all of today?s snowboards and bindings.
Visualisering av rotationer samt kvadratiska former i Linjär Algebra
Examensarbetet har genomförts på Campus Norrköping, Linköpings Universitet. Nätkursen och nätduggorna är ett samarbete mellan Linköpings Universitet (LiU), Kungliga Tekniska Högskolan (KTH) och portalen MATH.SE.Målet med samarbetet är att skapa och underhålla en webbsida (http://webcourses.itn.liu.se) i kursen Linjär algebra. Detta samarbete har skapats för att öka studenters intresse och öka deras inlärning i detta ämne. Anledningen till att dessa program behövs inom Linjär algebra är att det är svårt att förklara begrepp i tre dimensioner eller mer på en tvådimensionell tavla.Syfte med examensarbetet var att skapa en webbsida, som ökar förståelsen hos studenter som läser Linjär algebra. Med webbsidan skulle studenterna själva kunna interaktivt visualisera de moment i kursen som kan vara svåra att undervisa i ett klassrum.
Ruminants´production within agroforestry systems in rural Rwanda : production benefits and problems
Intercropping involving trees is called agroforestry and makes it possible to get higher production for every area unit. The trees can function as food, fodder, fuel, medicine; prevent mark erosion and much more. Agroforestry can also be combined with animal husbandry.
The aim of this study was to document the animal production systems used by rural small-scale farmers maintaining ruminants and using agroforestry in the northern province of Rwanda. The farmers using agroforestry is expected to have higher milk yield than average due to homegrown protein.
The method used during the study was semi-structural interviews with booth open and closed questions. In order to get in contact with farmers that matched the criteria; small-scaled rural farmers with ruminants and using agroforestry, the ?Vi Agroforestry Programme? (Vi-Life) in Kigali were contacted and the staff worked as supervisors, translators and contact with the farmers throughout the study.
During the study nine individual farmers, two cooperatives breeding sheep and one group interview were conducted.
The efficiency of the newly launched predatory mite Amblydromalus limonicus : biological control of thrips in cucumber
In this study, the efficiency of a newly launched predatory mite, Amblydromalus limonicus, has been
examined for its potential to use as a biological control agent in cucumber production. A. limonicus
can be used for biological control of two thrips species, Frankliniella occidentalis and Thrips tabaci.
Field trials were conducted in greenhouses of two conventional cucumber growers in Scania, the
southern part of Sweden. The basic control agent used against thrips was the predatory mite
Amblyseius swirskii. In selected areas, additional A.
Olika typer av täckning och samodling och dess påverkan på antalet skadegörare i en Pak choi odling :
The purpose of this report is to examine the possibilities to decrease the number of insects and other pathogens in a crop of pak choi (Brassica rapa), grown with different types of cover and living mulches. Included in the report is a study of literature where amongst others, a summary on the vegetable pak choi and theories of living mulches and different kind of covers are to be found. To examine the amount of predators in the field, traps were used.
During the autumn 2002 the tests were conducted in Alnarp. The pak choi and the living mulches were planted/sawn at the same time, the different covers were also applied at this time. The total experiment was divided into six different treatments (plus control) of which three were with covers and three were with living mulches.
Once a week the number of leaves, the height and damages were read on ten of the plants from each parcel.
Fallstudie av kostnader i tornsilo och plansilosystem på en mjölkgård :
I have through a case study looked on a milkingfarm in Dalarna and been counting on
what it would cost to increase the silagestorage. Today they have to little capacity on the
existing towersilo because they built a bigger farm with more cows. The reason is that
two families decided to start having the production on one farm together and moved all
animals from one of the farms to the other farm. So for that reason I have looked on the
costs to build a new towersilo or levelsilo.
The goal has been not only to look at the buildingcost but also which operatingcost that
is included with the different alternatives. I have taken tenders from two different
towersilocompany, Bjurenwall and Svenska Neuero and taken tenders from Abetong for
a levelsilo with roof and one without roof.
The overall feed requirements on the farm is on 240 tonnes dry extract and the old
towersilo hold 110 tonnes dry extract so the need for a new foundation is on 130 tonnes
dry extract.
I have through cost estimate been counting on the specific buildingcost for each
buildingaltenative.
Slutfasstyrning av missil med explicit prediktionsreglering
Arbetet har utförts på Saab Bofors Dynamics AB i Linköping och dess syfte är att undersöka möjligheten att applicera teorin för prediktionsreglering, Model Predictive Control (MPC), på guidance systemet i en missil av typen Medium Range Air-to-Air Missiles (MRAAM). Även implementering via Explicit MPC har undersökts. I tidigare studier har det visat sig att den moderna slutfasstyrningsalgoritmen Linear Quadratic Augmented Proportional Navigation (LQAPN), som återkopplar missilens acceleration och rotation, uppvisar en bättre prestanda än de mer klassiska styrlagarna. Det främsta intresset med denna studie är därför att undersöka hur tillvida en styrlag baserad på MPC kan mäata sig med dessa resultat. Fördelen med att använda MPC är framförallt att man kan ta hänsyn till styrsignalbegränsningar på ett direkt och intuitivt sätt.
Strängluftning av vallfoder : Inverkan på ensilagets torkningförlopp, spill och smörsyratillväxt
When harvesting ley you hope to get a fast drying and a faster harvest. If there is a
system with round bales, you need to have a dry matter close to 45 %. To make this as
fast as possible, there is made a machine which pick up the grass with an pick-up. It
turn the grass over and put it behind the machine (figure 2 and 4). There are few tests
to prove the efficiency of this machine.
Svängkranslagring för Kaldougn
Outokumpu Technology i Skellefteå fokuserar på teknik som härstammar från företag i Boliden-gruppen och deras gruv-, smältverks- och kemiska processer. Företaget erbjuder kunden ingenjörs tjänster i form av konsultverksamhet inom området från gruva till smältverk. Produkter för tillämpningar inom smältverk erbjuds också. En av dessa produkter är Kaldougnen som används för satsvis smältning och processbehandling av metaller såsom koppar, bly och ädelmetaller. För att lagra ugnens rotation används idag lagerrullar som vilar mot en löpring monterad på ugnskärlet.
Dödsgott med käk i kistan : En GCMS- och FTIR-analys av kermik från ett vikingatida gravfält i Alsike hage, Alsike sn, Uppland
This paper deals with the connection between food and burial habits during the late Iron Age in present-day Sweden. The archaeological material used in the study consists of 16 potsherds from a burial site at Alsike hage, Alsike parish, in the province of Uppland in east-central Sweden. On these potsherds have been conducted FTIR- and GCMS-analyses, in order to see what types of food have been deposited in the burials. Furthermore, the result of the GCMS-analyses has been compared to contemporary material from both burial sites and settlement sites, in order to establish whether differences between the compared materials exist. The analyses show that there are differences between the material from burial sites compared with the material from settlement sites, but not any particular differences between the material from different burial sites.
Avskogningen av Amazonas
Organic agriculture is financially promoted in Sweden by special environmental support and as consumers we are all encouraged to buy organic food. At the same time scholars at the Swedish University of Agricultural Sciences claim that organic farming does not provide any environmental benefits. The main criticism is that organic farming has lower yields than conventional, which means that more land is needed to produce the same amount of food as in conventional farming, leading to deforestation and loss of biodiversity. As for climate change, the critics claim that the significantly higher productivity in conventional crop production compared to organic, releases surplus land, which could be used for bio-fuel production and thereby replace the fossil fuels. The critics also claim that organic farming causes higher nutrient leaching than conventional.
Doseringsutrustningen SafeBond Electronic
This thesis for the Master of Science degree was performed at Oppunda Electronics AB. The assignment was to further develop an existing prototype of a dispensing equipment. The dispensing equipment doses a kind of glue, bonding which dentist use to mend teeth. The dispensing equipment is adjusted to dose 12 micro litres of bonding. With the dispensing equipment SafeBond Electronic the user can reduce the bonding consumption with approximately 50 percent.