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430 Uppsatser om Maximum velocity - Sida 6 av 29
Glacialgeologi i fjällranden : Undersökning för att spåra värdberget till ett zinkmineraliserat block
The valleys southwest of Storuman has been exploration targets for sulfide mineralizationslike the Laisvall Pb-Zn deposit since the late 1900 when several mineralized boulders wherefound. No previous glaciogeological survey has been made. This report focus on thedirections of local paleoiceflows and glacial transportation in the area of Skikkisjön, thelocation of the westernmost mineralized boulder, found in 2010. The aim of this study hasbeen to create a picture of the glaciogeological evolution of the area in order to determinatepossible hostrock areas. My results suggest that the geomorphology and transportationoccurred during a western icedivide located in the nearby mountainrange.
Beräkning av värmeförluster och energieffektivisering av elbussar
The ?civilized? world is in need of fossil fuel in order to function. Hybricon AB is a company in Umeå that is developing a technology that hopefully can reduce parts of this need. They are currently testing their two electrical busses (with Hybrid backup) in city traffic on the roads of Umeå in cooperation with the county of Umeå. The busses are originally diesel-busses, but the diesel motor has been replaced with two electrical hub-motors with a power of 145 kW each that are powered by batteries.The batteries are charged at the end station after each route. In case the batteries should run low on capacity during driving, they can be recharged by the so called genset.
Energieffektivisering av skolbyggnad från 60-talet : Studie av Hållsta skola i Eskilstuna
In June 2006 the Swedish government decided that the use of energy in buildings should be reduced by 20 percent until 2020, compared to the level of energy used in 1995. To contribute to this goal, the real estate company ?Eskilstuna Kommunfastigheter AB?, set up own goals for their buildings. In 2009, the goal for schools was to have a maximum energy use of 118 kWh/m2year for heating and hot water.The school ?Hållsta skola?, just south of Eskilstuna, exceeds the limit since it used 270 kWh in 2008.
Sensorfusion av GPS och IMU för en racingtillämpning
AIMS AB is a Swedish company that develops and sells inertial sensor systems. A new product is under research which basically is an aided inertial navigation system where unwanted drift is eliminated. This can be done by integrating a GPS reciever into the system and fuse measurement data from GPS and IMU. Such a product is useful in racing, where engineers always are searching for the optimal performance and the shortest lap times. Today the only feedback the engineers and mechanics get from their work is the driver?s comments and lap times.
Planseparerad spårtrafik i Göteborg
The City of Gothenburg has an urgent need to upgrade its public transport. The capacity of its light rail transit (LRT) has reached maximum capacity within the inner city limits years ago. The construction of an underground metro will be very expensive and time consuming due to the soft clay beneath the city. The apparent need of developing another type of mass rapid transit (MRT) is urgent. An elevated metro have turned out to be a success in Greater Vancouver, but is it possible for the system to operate well in Gothenburg with its narrow streets and current land use; will its route coexist with the current LRT or will the noise disturb people too much?.
Dynamiska egenskaper hos håldäcksbjälklag belastade med gångtrafik
Concrete floors have traditionally had no problems with annoying vibrations. However with the demand for larger spans the floors need to be made more slender with a higher degree of utilization and lower mass. Therefore new floors may have problems with vibration serviceability. This thesis studies the vibration characteristics of hollow core slabs. The analysis was made in the finite element program Ansys. The hollow core slab was subjected to a varying force simulating one person walking across the slab.
Optimering av sintrade kugghjul
Powder Metal (PM) gears are machine element components which operate under the same principle as conventional gears, but, due to their intrinsic material characteristic need to be designed slightly different, and its manufacturing process offers advantages previously unobtainable by conventional steel gear manufacturing methods. The use of PM in similar applications, such as synchronous hubs, makes them a suitable candidate for production in such material. The current master thesis work focuses on gear design using PM by utilizing finite element method (FEM) to reduce weight and inertia taking into account root bending strength and tooth deflection.First a topological optimization is used to determine feasible candidates for different web designs which have as objective to reduce volume, similar topologies were shown during different loading conditions; and hence, this topology was chosen as a suitable candidate. A shape optimization of the topological candidate was performed having as state variables root bending strength, independent for compressive and tensile side of the tooth loading; and tooth deflection, which in concept can be correlated to static transmission error (TE).Another aspect in this thesis analysed is the possibility to incorporate non-trochoid root geometry, a trochoid root is always present when machining with a hob, into the gear root and hence reduce the stress concentration here. Due to the use of PM, a non-symmetric optimized root can be achieved and hence be optimizing compression and tension.Results showed significantly lower inertia, for example certain results showed 40% reduced when compared to solid gear, with adverse effects as increase in tooth deformation and increase in maximum principal stress.
Lågoffsetkomparator
Detecting small signals with a comparator demands that the total voltage offset is lower than the actual signal. The total offset includes the voltage offset in the comparator and the voltage offset that is created by the offset currents that flows thru the load at the comparators input. The goal with this comparator that has been developed has been that it will have a total voltage offset at maximum 500 uV. The comparator does not need to be extremely fast or does not need to operate in a big frequency area. To have all the flexibility that is needed a full custom technique is used.
FPGA baserad PWM-styrning av BLDC-motorer
This thesis work contains a litterature study about electrical motors in general and how PWM-patterns for brushless DC-motors can be made. A suitable method has been implemented as a simulation model in VHDL. A simulation model of a brushless DC-motor which describes the phasecurrents, torque and angular velocity has also been made. The motor model made simulations easier for the complete PWM-system. The design was synthesised and tested with a prototypeboard including a SPARTAN II FPGA.
Optimal bredbandig vågform framtagen genom generaliserad osäkerhetsfunktion
The waveform of a radar signal affects the resolution in velocity and distance. The ambiguity function is used as an aid for analysing narrow band radar signals simultaneously in time and frequency. An analysing tool for wide band radar signals is missing.This thesis describes a generalised ambiguity function to be utilised for study of wide band signals. Waveforms are further synthesised with help of the developed analysing tool. The aim is to start with a certain ambiguity function and find a waveform that reproduces the same ambiguity function.Mathematical formulas are presented and implemented in Matlab to produce the wide band ambiguity function.
Effekter av spädningsvätska på motilitet och fertilitet hos hingstsperma : en jämförelse av subjektiv motilitetsbedömning och QualispermTM
At SLU, Divison of Reproduction, Dept of Clinical Science, there is an ongoing project on the development and evaluation of new methods for the assessment of stallion semen quality. This EEF-study, which is a part of that larger project, has focused on the effects on motility and fertility of stallion semen of two different extenders and selection. Both an objective method and a subjective method for analysis have been used and compared in the study.
The increase in the use of artificial insemination with cooled semen in Swedish horse breeding over the last decade is thought to play a part in declining foaling rates (Kareskoski et al, 2006, Kuisma et al, 2006). This calls for better evaluation methods of semen quality since cooling and transportation put higher demands on semen quality in order to maintain fertility (Aurich, 2005).
Undersökning av mätsystem och regulatorstrukturer för industriella tillämpningar
This thesis is divided in to two different parts. The first part includes examination of the measurementsystem of an industrial robot using a resolver sensor. The main focus is on methods for suppressing noise in the angularvelocity signal without increasing timedelay. Five different methods are investigated. Three of these are based on oversampling: burstsamplingmethod, meanvaluemethod and correlationmethod.
Akuta effekter av assisterade hopp på kvinnliga idrottares hoppförmåga
Vertical jumping ability is an essential skill in many sports. The aim of this study wasto investigate the acute effects of assisted jumps on subsequent countermovementjump (CMJ) performance by female athletes. Nine healthy, trained female subjectsvolunteered to participate in the study. In a randomized order, they performed oneregular warm up protocol before testing their CMJ baseline value, and one warm upprotocol with an addition of five assisted jumps at 30% body weight reduction beforeanother CMJ test. Elastic cords attached to an overhead pulley system and to aharness around the subjects' upper body were used to reduce the body weight.Significant improvements were noted in jump height, 2.3 cm (7%), positive forceimpulse, 4.7 Ns (2%), vertical take off velocity, 0.1 m/s (3%), countermovement time,0.1 s (12%) and breaking time, 0.1 s (14%), p.
Digital videoväxel
This thesis discusses the possibilities to distribute digital video in a military vehicle. Today, an analogue system is used, which has a maximum capacity of eighteen video sources and the same number of monitors. The purpose of this thesis is to increase the systems capabilities regarding secure distribution and additional functions. Both software and hardware tests are made to investigate the features of the digital video standard MPEG-2. Both the coding delay and the image quality are of great interest.
Utveckling av en metod och en utrustning för mätning av bränslesprayers rörelsemängd
A new type of device for measuring thev m& ?rate of fuel sprays from a diesel fuel injector has been developed and the various steps in the development are described. The device works by deflecting all of the sprays from the injector at the same time by using a bell shaped deflector. A load cell consisting of a machined steel part with strain gauges mounted on it measures the resulting force. The shape of the curvature in the deflector bell shape has been evaluated by photographing the flow in a 2D?version of the curve shape.