
Sökresultat:
1779 Uppsatser om Mechanical engineering - structural dynamics - Sida 31 av 119
Föränderliga stadsrum : flexibilitet, dynamik & interaktivitet
The number of inhabitants of the towns and city centers have generelly increased, concurrent as the population in smaller towns has decreased. In Stockholm, the migration is very fast and here is also the most populous place, if one compares with other Sweden.
In order to respond to the increasing population and the pressure they put on city spaces has Stockholm's town a town building strategy that says "build inwards". It means that one stem seals the town with spaces and business activities in central locations.
The increased population in the towns and the densification of buildings leads however to an increased pressure on parks and public places.
Användbarhet på fass.se
Webbplatsen fass.se är idag anpassad för folk inom vården. Nu vill man göra en ny version av webbplatsen som är anpassad för allmänheten. Detta ställer stora krav på användbarhet. Så länge någonting fungerar som det ska och går precis som man tänkt så tänker man inte på det. Saker och ting kan vara enkla att lära sig och de kan vara effektiva att använda när man har lärt sig det.
Utvärdering av en Magnetic Harmonic Traction Drive
In this report a new gear concept is evaluated using the magnetic finite element method (FEM)software MagNet and Ansys as well as the mechanical FEM software Abaqus. The gear conceptis evaluated in terms of maximum torque capability, torsional stiffness, gear ratio and efficiency.ABB Corporate Research has proposed a new gear concept which should be less expensive thangearboxes used today. The new concept is called aMagnetic Harmonic Traction Drive and usesthe principles of a harmonic drive gear to achieve a high reduction ratio. The gear conceptreplaces the wave generator used in traditional harmonic drives with magnets and uses tractioninstead of gear teeth to transfer the torque. The main components in the gearbox are the magnets,the flexspline, the magnetic portion and the circular spline.
Omkonstruktion av en rollators bromssystem
This diploma work project is a product development project which purpose is to redesign a braking system for a walking frame. The system that was developed diverges the force from the user to braking power, and includes a service brake as well as a parking brake. The most important components of the system are a grip handle on where the user holds on to and a braking handle on which the user operates the brake from. The system also includes a power transmission component, braking package and other mechanical components. All of the components wasn?t developed in this project, several off them has been reused from the existing system.This product has been developed to meet the requirements and standards presented from the principal, Ahlberg Leber.
Möjligheter att minska kväveutlakningen genom att anpassa kvävegödslingen till variationer inom stråsädesfält
Due to excess precipitation that cause runoff, all soils in Sweden naturally leaches nitrogen.High leaching from arable land is an environmental problem when the runoff reacheswaters. In the international agreement, Baltic Sea Action Plan, the aim is to reduce therunoff of nutrients. Sweden has agreed to reduce its load of e.g. nitrogen to the Baltic Sea.One of the proposed measures is an increased use of site-specific N-fertilization, which hasbeen shown to increase nitrogen use efficiency and therefore also reduce the nitrogen runoff.Either yields are increased with the same total amount of nitrogen, or the total quantityof nitrogen is reduced with preserved yield levels, which is profitable for the farmers.The dynamics of nitrogen leaching differs between top dressing applications above orbelow the economical optimum. There is a consensus about a difference in the dynamics,but not about its magnitude.
Framtagande av kravspecifikation för standardsystem
There are several methods and models within the areas of software engineering on how to proceed during a software development process. For each of these methods and models there are benefits and drawbacks, depending on how you choose to look at them. A difference of principle between the different models is that they either advocate iterative development or not. In parts of software engineering one makes use of different methods depending on which is most fitting in a specific situation. There are several methods on how to recieve more qualitative data from the end-users during the requirement collection, but the reappearing pattern is still user centric participation, which means that the user participates more actively in part of or the entire development process.
Framgångsfaktorer i integrationen av elever med särskilda behov i den allmänna skolan
The purpose of this paper is to identify and analyze success factors in the integration of students with special needs in regular schools. This will be done through the case study of a nine year old autistic student in a small town public school ? a fairly representative case for the Swedish school system. The data collection methods used in the paper are; three participant observations of the student, and a qualitative interview with two of the student?s teachers.
Termomekanisk utmattning av Sanicro 25 : Materialmodellering med finita elementmetoden
The report aims to describe the austenitic stainless steel Sanicro 25 from a thermomechanical point of view. The thermal and mechanical properties of the material make it suitable for use in coal ? and thermal power plants. By the use of Sanicro 25 it would be possible to bring the efficiency of these plants up while bringing the carbon emissions down.A material model is created from material testing and validated through simulation in the finite element software Abaqus. The model that has been derived describes the material behavior during loading and stress relaxation for the first cycle in a thermomechanical fatigue test well.
Spelskapande men en komponentbaserad arbetsprocess
Syftet med detta kandidatarbete är att testa en arbetsmetod som skiljer sig
ifrån det en mindre grupp i vanliga fall använder sig av: en komponentbaserad
arbetsprocess för att utforska och sammanställa arbetserfarenheten med den
komponentbaserade arbetsmetoden, utvecklar vi därför ett digitalt spel..
Missilstyrning med Model Predictive Control
This thesis has been conducted at Saab Bofors Dynamics AB. The purpose was to investigate if a non-linear missile model could be stabilized when the optimal control signal is computed considering constraints on the control input. This is particularly interesting because the missile is controlled with rudders that have physical bounds. This strategy is called Model Predictive Control. Simulations are conducted to compare this strategy with others; firstly simulations with step responses and secondly simulations when the missile is supposed to hit a moving target.
Aktivt system för tidvattenreglering av Lysekilsprojektets vågkraftsteknik
This report investigates a possible solution to the problem with adapting wave powerplants to work in countries with tidal water. The wire connecting the buoy at the surface with the generator at the bottom needs to adjust to the varying water depth. Our solution to this problem is to attach the wire to a jack which is then placed inside the buoy. The jack is then powered by an electric engine. The report discuss what forces the buoy will be exposed to and then the structural integrity of the design is evaluated through simulations.
Design av motorstyrd lyfthjälp till toalettstol
The objective with this project was to design a new lifting aid connected to toilet chair.A questionnaire distributed at three homes for aged people indicated that there was an interest in a mechatronic lifting device.Since existing products have limited tilting functionality, the new design was chosen to introduce lifting by motorised tilting of the sitting platform. The mechanical construction was analyzed based on a maximum load caused by a person with weight 160 kg. Two linear actuators were used to control the tilting/lifting of the sit ?place, making standing-up easer.Finally, 28 persons tested the new lifting device and gave their impressions. Many appreciated the safe, stable lifting speed.
Utveckling av rullstolsunderrede för individsanpassade sittsystem
I denna rapport redovisas arbetsgången för produktutvecklingen av ett rullstolsunderrede med nya design- och konstruktionslösningar. Det slutliga konceptet är ett underrede med två centrala konstruktionslösningar; en hydraulcylinder som medger vertikal sitthöjdsjustering, samt en vaggfunktion i sittplattan som medger ökad balans vid vinkeljustering. Samtliga funktioner på underredet har anpassats för att erbjuda ett enklare och renare ramverk..
När ska dieselelektrisk framdrift av fartyg väljas?
Diesel electric propulsion is in many ways a good alternative to conventional shaft propulsion, both economically and environmentally. There are also many other good side effects which need to be considered, i.e. better manoeuvrability, more efficient use of space and less noise on board. However, there are applications where diesel electric propulsion is not profitable. Large ocean going ships? profitability is much depending on fuel costs and the diesel electric alternative cannot compete on long journeys with large low speed engines.This thesis will treat the aspects of choosing between a diesel electric system and a classic mechanical propulsion system.
Ska du verkligen komma in? : Missbrukare och deras relationer till majoritetssamhället
This essay will focus on drug addicts and their relations to the majority society in Sweden. The concepts of ?subculture? and ?stigmatization? applied to drug addicts are central in the analysis. The essay is based on interviews with two different groups of informants: one consisting of drug addicts and the other of non-addicts. The essay describes, analyses and interprets the informants? ways of relating to society and the observed tendencies of being a part of a subculture as well as obejcts of stigmatization, both individual and structural..