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164 Uppsatser om Hydraulic cylinder - Sida 7 av 11
Simulering av mekaniska system med Lagranges metod
Mekaniska system har länge varit av intresse för vetenskapenoch vår förmåga att matematiskt beskriva dess dynamikär mycket god. Att effektivt kunna härleda de nödvändigaekvationerna är dock inte trivialt och uttryckensom bildas är ofta icke-linjära differentialekvationer som ejleder till explicita lägesbeskrivningar av de rörliga komponenterna.Idag finns kraftfulla matematiska metoder ochdatorverktyg som möjliggör simulering av relativt komplicerademekaniska system vilket denna rapport ägnats åtatt undersöka med hjälp av exempelsystem. Två utvaldamekaniska systems beteenden med varierande begynnelsevillkorhar undersökts med hjälp av datorsimuleringar. Detförsta systemet har bestått av två pendlar med en fjäderfastspänd mellan pendeländarna. Det andra systemet harbestått av en fritt rullande cylinder på horisontellt underlagmed två pendlar fastspända på änden.
Produktionsstyrning av cylinderbricka : För Atlas Copco, Tierp.
The component workshop at Atlas Copco inTierp intends to reduce the costs inorder to increase their competitiveness.This thesis examines how the productionmanagement around cylinder washersshould be managed in a way that meetsthe customer needs. The customer to thecylinder washer is Atlas Copcos assemblydepartment in Tierp.The purpose of this thesis is to providean alternative way of managing theproduction. A chapter of theory is addedto give the reader an insight ofdifferent types of production managementsystems as well as the underlyingknowledge needed to get a better readingexperience. An introduction of kanbancan in theory help Atlas Copco in thedirection they strive. It should beclear how the purpose of this thesisaffects the cost for the componentworkshop and also how it relates to thecurrent production.
ESC-analys och studering av knack på en "Diesel Dual Fuel"-motor
A one-cylinder research engine has been used for studies with a Diesel Dual Fuel concept (DDF). DDF is a concept that utilizes a pilot diesel injection to ignite a homogenous natural gas/air mixture. Emissions and engine efficiency have been analyzed in an emission cycle called European Stationary Cycle (ESC) and the knock/pre-ignition problems with this type of engine have been investigated.At low and mid torque levels, an early diesel injection around 60 crank angles degrees (CAD) before top dead center (TDC) was used. At these loads raw NOxemissions was below EURO 6 level (0.2 g/kWh). NOxwas at EURO 5 level over the complete ESC without after treatment and with SCR at high loads it should be possible to reach EURO 6.One issue with DDF is the high HC emission levels.
Gener som påverkar pälsens utseende och hälsan hos hästrasen American curly
American curly hästar har lockig päls och drabbas i vissa fall av hypotrikos vilket innebär håravfall. Många tappar förutom pälsen även manen och svansen när de fäller. Lockig päls förekommer även hos katt, hund, mus och tamråtta samt extremt lockigt eller ulligt hår hos människor. Flera av dessa är även drabbade av hypotrikos. Syftet med denna studie är att studera vilka gener som troligtvis styr utseendet och hälsan hos american curly.
Testikelmått och daglig spermieproduktion hos svenska halvblodshingstar :
Testicular measurements and daily sperm output (DSO) are important factors affecting reproductive capacity of stallions. In the present study testicular measurements of 10 Swedish half-blood stallions were determined (height, length, width and volume). Ejaculates were collected from each stallion once daily for 10 days to evaluate some important seminal characteristics: gel-free ejaculate volume, sperm concentration, percent progressively motile spermatozoa and total number of spermatozoa (TSN). The gel-free ejaculate volume was measured with a graduated cylinder, the sperm concentration was counted in a Bürker chamber, the sperm motility was estimated in a phase-contrast microscope and TSN was determined by multiplying the gel-free seminal volume by the sperm concentration. Testicular measurements were as follows (left and right testis): height 7,5 cm and 7,8 cm, length 10,6 cm and 10,8 cm, width 6,5 cm and 6,6 cm, volume 278,2 cm3 and 293,8 cm3, scrotal width 12,3 cm and total testicular volume 572,0 cm3 .
Glidytor och ytjämnhet med avseende på friktion och tätning
Gliding and sealing functions in Öhlins shock absorbing systems sets great demands onthe contacting surfaces. In this particular case, the bushings and the sealings on acylinder piston. The surface wanted is a surface with both low frictional forces and smallleakage. This study was done with the goals of investigating and determining existingsurfaces due to the frictional force and leakage. How can we in an easy mannerdescribe these?A number of ten front forks were part of a main study.
Odlingens och lagringens inverkan på utsädes grobarhet :
At seed-growing the aim is to produce a commodity with high germination capacity, good soundness
and purity, and also slight admixture of seeds from other species. The capacity of germination and the
vigour of the seeds may become impaired in consequence of mechanical damage, infection of diseases,
growth of mould, attacks of vermin, high drying temperature, secret germination, sprouting in the ears
etc. The germ belongs to the outer and most unprotected parts of the seed, and consequently this is
much exposed. Even quite sound seeds can instantaneously have low capability of germination. It can
be due to the fact that the seeds are in rest of germination, i.e.
Järnvägsväxlar som tål snö och is
De senaste åren har stora tågförseningar skett på vintern, ofta hänvisade till som växelfel. Dessa växelfel beror ofta på att snö och is fastnar i växeln och på så vis förhindrar växelns huvudfunktion. Snön hamnar i växeln dels genom snöfall, men även på grund av att snön skakas av från de passerande tågen. Förseningarna, som beror på snö och is i järnvägsväxlar, är ett stort problem som påverkar många människor. Syftet med detta projekt blev således att undersöka hur detta problem kan lösas.Idag finns redan flera varianter för att lösa detta problem.
Förbättring av tillgänglighet robotcell för diskmaskinsbehållare samt cylinder-behållarline tvättmaskinscylindrar och behållare
The ability to tackle NP-hard problems has been greatly extended by the introduction of Metaheuristics (see Blum & Roli (2003)) for a summary of most Metaheuristics, general problem-independent optimisation algorithms extending the hill-climbing local search approach to escape local minima. One of these algorithms is Iterated Local Search (ILS) (Lourenco et al., 2002; Stützle, 1999a, p. 25ff), a recent easy to implement but powerful algorithm with results comparable or superior to other state-of-the-art methods for many combinatorial optimisation problems, among them the Traveling Salesman (TSP) and Quadratic Assignment Problem (QAP). ILS iteratively samples local minima by modifying the current local minimum and restartinga local search porcedure on this modified solution. This thesis will show how ILS can be implemented for MSA.
Geotermisk fjärrvärme i Gunsta
Gunsta is situated about 10 km east of Uppsala. Today there are plans to establish 1000 new households in Gunsta before year 2030. The required energy for heating houses and water would be distributed via a district heating system, which also includes 200 existing residences. The annual required energy, according to this study, would be 16.2 GWh with a maximal peak effect of 6.9 MW.
To meet this need, the study suggests a system with heat pumps to upgrade the 31?C water from a 1.8 kilometre deep borehole.
Biochar as soil amendment in flow-through planters - for increased treatment of zinc roof runoff
In times of increased flooding, enhanced by climate change, polluted stormwater poses an increased threat to the environment through contaminated water entering waterways. Bioretention utilizes natural processes in soil and vegetation to treat pollutants and combat this threat. Biochar produced through pyrolysis, has a high cation exchange capacity (CEC) and could therefore increase treatment in bioretention systems. This research applies a literature review, interview, and a model to explore the benefits and disadvantages of biochar in order to specify a soil-mix through an understanding of the production process and preferred application rate. High purification through CEC, increased water holding capacity, and carbon sequestration being the benefits discussed.
Analys och utveckling av boggi till ramstyrd dumper
Volvo Construction Equipment is one of the worlds largest manufacturer of heavymachinery. In Braås, Sweden, they develop and manufacture articulated haulers inseveral sizes. The biggest, the A40, is capable of loading almost 40 metric tonnes.These haulers have a bogie to distribute the forces of the load evenly onto the two axlesand there wheels. The bogie is constructed using a rigid balance beam on each side ofthe frame connecting the axles or an independent solution using hydropneumatics.An analysis has been made in order to establish the forces created during corneringand through the theory, an estimation of the extensive tyre wear and extra fuelconsumption has been made. All due to the effects of the tyres not being inline with thecornering radius.
Utveckling av programvara till ett inbyggt styrsystem
This thesis considers the development of the software for an, newly developed, embedded real-time control system, based on a Periferal Interface Controller (PIC). The control system is developed to be used for several different applications. In this thesis work, software for two different applications are developed. The first task is a time controlled system, while the other task is implementation of aPI-/PID-controller. A user interface is also developed and implemented.The time controlled system is an automatic horse feeder, which is used for feeding horses at certain predefined points in time.
Minkvalpars beteende i större berikade burar vid olika gruppstorlek :
Farmed mink often perform stereotypic behaviours which is considered to be a sign of reduced welfare. Previous studies have shown that enriched cages can reduce the frequency of performed stereotypies. Most studies on mink in Sweden have been done on adults. The aim of this study was to investigate if larger enriched cages with two or four mink kits reduce stereotypies in mink kits during their growth period in comparison to traditional cages.
In the present study the behaviours of mink kits that were kept in four different treatments at a private mink farm were recorded. Traditional cages with two mink kits were used as a reference and the other treatments consisted of larger cages with shelves with two kits, larger cages with shelves and a plastic cylinder with two kits, and larger cages with shelves with four kits.
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?.