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430 Uppsatser om Maximum velocity - Sida 1 av 29
CFD simulering av kallras : Undersökning av temperatur- och luftbeteende intill höga glasfasader och i vistelsezon med golvvärme som en värmekälla
Glass has sophisticated front properties and are used as facades in high buildings. During cold periods, these glass facades could cause thermal discomfort, due to cold downdraught. Cold downdraught can be countered by placing heaters under glass surfaces. Nowadays technology offers highly insulating windows, which is why there is an interest to investigate the indoor climate with only underfloor heating. The research in this area is limited, and few empirical methods are available.
Hastighetsmätning av kolvrörelser i pneumatiska cylindrar
The purpose of this thesis was to investigate different methods do measure velocity of pistons in pneumatic cylinders at Bosch Rexroth Teknik AB. Through information of velocity the adjustment of a cylinders damping can be done easier.A future transducer will be used by salesmen, service personnel and customers. This requires a sensor that is easy to apply and use. It is also desirable that the sensor is cheap. A number of possible methods to measure velocity have been presented.
Bearbetning av GPS-data vid Flyg- och Systemprov
At Flight and Systems test Saab AB, a post-processing software is used to process GPS data. A new software by the name GrafNav has been purchased and the purpose of this master thesis therefore became, partly to make a judgment regarding GrafNav?s ability to estimate position, velocity and accuracy, partly to if needed improve the estimate and finally find one or several methods to estimate the position and velocity accuracy. The judgment of GrafNav was performed partly by a comparison to the former post-processing software (PNAV) and partly by a comparison to the airplane?s inertial navigation system (INS).
Vilken preferens har tjockskalig målarmussla (Unio crassus) för bottensubstrat och vattenhastighet i Storån, Östergötland?
The thick shelled river mussel (Unio crassus) has a fragmented distribution in southern Sweden. It is a threatened and protected species. In both the Swedish red list and the IUCN Red List of Threatened Species Unio crassus is classified as Endangered (EN). Causes for this classification are for instance differentiated bottom substrate and deterioration in water quality. In this study, habitat preferences of Unio crassus were investigated to assist in future restoration work.
Oljefilmens tjocklek mellan kolvring och cylinderlopp
Hägglunds Drives in Mellansel, Sweden, manufacture radial piston hydraulic motors foremostwithin applications in the industry. These motors have several sliding contacts, one of these, isthe contact between piston ring and cylinder bore. The radial piston hydraulic motors advantageis to produce high torque in very low rotation velocity, this result in that the maximum slidingvelocity between piston ring and cylinder bore, during the whole stroke, is very low. Theconsequence of this low sliding velocity is that the contact between piston ring and cylinderbore, during the whole stroke, is bound to the boundary lubrication regime. This result in, thatthe piston ring is exposed to wear, thus affect the service life of the complete hydraulic motor.To minimize wear of piston ring, it is essential to determine the oil film thickness between thepiston ring and cylinder bore.
Pre-spawning habitat selection of subarctic brown trout (Salmo trutta L.) in the river Vindelälven, Sweden
Habitat selection of migratory brown trout at the upper reaches of River Vindelälven, wasstudied in September during the pre-spawning period. The fish migrate from down- orupriver lakes for spawning in the river and data was collected by habitat mapping andradio-telemetry. Habitat selection of fish was analysed with preference curves andstatistical modelling, using the physical variables; depth, stream velocity and streambedsubstrate. Preference curves were derived by comparing fish habitat use with their nearbyavailable environment while the statistical modelling aimed to answer three main questions.1) Do the trout have a specific preference of depth, water velocity and streambed substrate?2) Is there any difference in habitat selection between sexes? 3) Is there a shift in habitatselection over time? The preference curves indicated that trout favored water depths of 1-2m, velocity compositions characterized as glides (c.
MPD-vågformer för helikopterradar
A helicopter based system equipped with a millimetre-wave fire control radar is studied for improvement of the detection probability for moving ground targets. The system is a pulse doppler radar that sends out the electromagnetic wave in repetitive pulses. The frequency in which radar sends this pulse is called Pulse Repetition Frequency (PRF). The velocity of the moving targets is measured by spectral analysis of the pulses received. With this sort of system some targets will not be possible to detect.
Elitbandyspelares rörelseprofiler i förhållande till olika spelarpositioner
Inledning: Bandy är en vinterlagsport som innehåller både fysiska och tekniska krav. Till författarnas kännedom finns begränsat med vetenskaplig forskning om bandyspelares fysiska krav under match. Syfte: Syftet med denna studie var att beskriva manliga elitbandyspelares rörelseprofiler utifrån total distans, maximal hastighet, medelhastighet, speltid, hastighetszoner och acceleration under matchsituation mellan olika spelarpositioner. Metod: Datainsamlingen utfördes med tio hertz GPS-enheter på ett elitserielag i bandy från mellersta Sverige under säsongen 2014/15. Sex till åtta manliga elitbandyspelare studerades under elva matchtillfällen.
Klimatsimulering av ett kontorsrum : Hur de termiska stigkrafterna påverkar ventilationseffektiviteten
AbstractIn urban societies people spend more and more time indoors, which put great demands on the indoor environment. If the ventilation is to manage the removal of unwanted substances in the indoor air, a good mixing of the air is required. The question arises that, whether the buoyancy forces will counteract a good mixing of the indoor air or not?This report aims to clear up the difficulties whether you need to consider the buoyancy forces or not, when adjusting a ventilation unit. For studying the indoor mixing of the air a two dimensional model is constructed in COMSOL Multiphysics.
Scintigrafisk undersökning av esofagusmotilitet hos häst :
Scintigraphic examination of the esophagus has for some time been the method of choice for the study of motility dysfunction in humans. The method has not yet been described for horses hence the lack of reference values for passage time for a bolus through the esophagus in healthy subjects. The purposes of this study were to measure passage velocity and time for a bolus to pass through the esophagus in healthy subjects, as well as to evaluate the reproducibility of the method. Eight warm-blooded trotters were used in the study. The horses were sedated with a low dose of Acepromazine prior to onset of the study.
Mjölkens ureahalt och mjölkkornas kväveeffektivitet :
Jordbruket står för en stor del (90 %) av ammoniakutsläppen I Sverige och nötkreaturen står för 71 % av dessa utsläpp. Ammoniak är en kväveförening som kan ge upphov till miljöproblem som övergödning och försurning. För att kunna förbättra kväveeffektiviteten och därmed minska ammoniakutsläppen behövs bra instrument för att se vilka åtgärder som behövs och var i produktionen de bör sättas in.
Det här arbetet har som mål att utröna om mjölkurea kan vara en indikator för mjölkkors kväveeffektivitet, samt att förse rådgivare med hjälpmedel i arbetet mot ett högre kväveutnyttjande i mjölkproduktionen. I studien deltar 19 besättningar. Utfodringen och dess kopplingar till mjölkurea studerades.
Sambandet mellan hästens huvud/halsposition och ryttarens rörelse i sadeln :
Dressage schooling is not a subject that rests on science, it is a matter of dependable experience. So far there hasn?t been so much research about it, but more and more is done. Especially the interaction between rider and horse is a nearly uninvestigated field. Riding skills is much about having the right position, and having the horses head and neck in different positions, but there are no research done that support or deny that this old ?knowledge? is for the best for the horse.
This study was performed to evaluate if the head and neck position of the horse, and the velocity, has any influence on the position of the rider.
Dimensionering av betongplatta på lös undergrund. En jämförelse mellan tre beräkningsprogram
Today more effective computer programs are in use, regarding design of geotechnicalconstructions. There is a risk that the theoretical background of the computerprograms, its limitations and the signification of the choice of soil parameter isforgotten when the computer programs become more user-friendly.This Master thesis deals with simulation and analysis regarding three computerprograms, FEM-design, with the addition Raft, Plaxis and BE-slab. Comparisons aremade for settlement and maximum moment in a concrete-plate. FEM-design is a threedimensional FEM-program, foremost created for design engineers. Plaxis is a twodimensional FEM-program, intended for geotechnical engineers while BE-Slab is aBoundary elements program in two dimensions that is mainly used by designengineers.
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.
Industriellt byggande – en nulägesrapport
Today more effective computer programs are in use, regarding design of geotechnicalconstructions. There is a risk that the theoretical background of the computerprograms, its limitations and the signification of the choice of soil parameter isforgotten when the computer programs become more user-friendly.This Master thesis deals with simulation and analysis regarding three computerprograms, FEM-design, with the addition Raft, Plaxis and BE-slab. Comparisons aremade for settlement and maximum moment in a concrete-plate. FEM-design is a threedimensional FEM-program, foremost created for design engineers. Plaxis is a twodimensional FEM-program, intended for geotechnical engineers while BE-Slab is aBoundary elements program in two dimensions that is mainly used by designengineers.