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945 Uppsatser om Stability calculations - Sida 15 av 63

Elektrisk skorstenständare

Between 1965 and 1974, the Swedish Parliament decided to build one million dwellings, called Million Program. The million program buildings were erected with new, untried design solutions, in a short range of time, and at low cost. The residential buildings from that time are now greatly in need of renovation. The municipal housing company, Gavlega?rdarna, renovates and improves the energy efficiency at some of it?s apartment buildings in the district Sa?tra, Ga?vle.

Objektdetektering i SAR- och IR-bilder

This report treats detection in IR-pictures taken from airplanes over the ground. The detection is divided in two parts. First there is a detection with filterkernels with the task to point on targets and objects that look like targets. The second part is a discriminator that demands more calculations and has the task to sort out the false alarms from the discriminator. Both the detector and the discriminator contain thresholds thats been trained from trainingsets of data.

Vilometabolism hos barn och ungdomar med Cerebral Pares : En deskriptiv korrelationsstudie

Background: Cerebral Palsy is usually divided into three subgroups: ataxic, spastic and dyskinetic, where children and adolescents can, because of misestimation in nutrition and energy intake, suffer from weight problems.Aim: To compare calculations with equations with the individual's measured RMR in the subgroups, to see if any equation is more suitable. This could be used as a tool to calculate the resting metabolism at times when it is not possible to perform clinical measurements.Method: The RMR has been measured in 37 children and adolescents aged 3-15 years through indirect respiratory calorimetry. Those values have been compared with calculations from five equations. The results were then analyzed in order to find if any equation is better to apply for calculating resting metabolism for each subgroup.Results: The ataxic group was overestimated by 56.5% of the calculated values. WHO/FAO/UNU?s equation indicates a significantly strong correlation between the measured and calculated values (r=0.85, p<0.05).

ENERGI- OCH KOSTNADSEFFEKTIVAMATERIALVAL I VÄRMESYSTEM : En jämförelse av rörmaterial i vattenburna värmesystem

The thesis aims to compare differentpiping materials in heating systems interms of cost as well as to illustratethe impact of energy characteristics ofdifferent materials over its servicelife. The methods used for costcalculations regarding piping are alsoto be examined to highlight thedifferences between template basedcalculations and more carefully executedones. The work is delimited to discusspipes of steel, copper, plastics andcomposites. The aim is that the resultcan be compiled to illustrate the prosand cons of various materials whenevaluating investments.The main object of the survey is part ofa heating system in the office-block KVSommaren located in southern Stockholm.The configured piping system is designedwith the mentioned piping materials andis used to make up the data for flow andcost calculations. The differentmaterials are calculated in both aconventional manner with a supplementarycost for additional fittings and with amore accurate quantification of thecomponents.

Utveckling av nytt koncept för positioneringsslid

A manufacturing machine at the engineering company Sandvik Coromant has a positioning table which task is to move an item linearly. The positioning table has a linear motor capable of high velocity and acceleration. This makes it possible to achieve short cycle times and a more profitable production.The purpose of this thesis is to bring forward a new concept which is more adapted to the requirements of the positioning table. The reason is that the current positioning table provides an unnecessarily positioning accuracy of 0.01 mm, while the requirement for the positioning accuracy is just 0.1 mm. The goal is to reduce manufacturing and component costs.To develop a suitable solution an approach for the concept development process has been performed.

Utvärdering av magnetiska alternativ till optisk scanning

This thesis includes an energy survey of the Herrgården pre-school, which has a modern heating- and ventilation system, and a comparison with Östers pre-school which has an older system. An energy survey of Östers pre-school has already been done by a group of three students and all the calculations and values have been collected from that survey. As of today, both pre-schools are heated thru district heating. It will be much easier to make smart and feasible energy-saving-measures by first conducting the energy survey.Herrgården pre-school in Gävle houses 81 children, therteen teachers, one cleaner and one cook. It was finished in the middle of 2009 and the staff has been very pleased with the in-door climate.

Utvärdering av en ny typ av lagerinbyggnad för traktionsmotorer

The thesis evaluates a new kind of bearing arrangement in a traction motor that ABB hasdeveloped. Since the arrangement is designed in a new and innovative way it needs to beevaluated to see if it is safe to use. In today?s traction motors, bearings with a big internalclearance (C4-clearance) are used. The basic idea of the new arrangement is to reduce the fitsbetween the bearing and shaft/house.

Solenergi på Kvarnholmen

In recent years it has become more and more evident that man has contributed to much of the climate changes that have taken place during the last century. A major challenge today is to reduce emissions and energy usage at the same time as the global population is growing. To contribute to a better environment, Stockholms Stad has set at target of becoming fossil fuel free by the year of 2050. The construction of new districts is done with this goal in mind; energy efficiency and renewable energy sources are examples of methods to achieve this.Solar energy is considered to be a sustainable energy source and the most common techniques to harvest solar energy in Sweden are solar cells and solar collectors which produce electricity and heat respectively. This report aims to investigate whether an investment in any of these systems would prove to be economically beneficial at Kvarnholmen, a district under construction in eastern Nacka, Stockholm.Since the finished blueprints only cover a small portion of Kvarnholmen, the report examines the possibilities for a house where construction has already begun, Nya Kvarnen.

Automobike: en cykel med aktiv balans

During spring 2012, six students at the Royal Institute of Technology in Stockholm carried out agroup project in the field of mechatronics as part of the thesis for the bachelor degree. The resultwas a robot with active balancing and the purpose of this report is to describe the development,manufacturing and problems that arose during the project. The finished robot has two wheelsmounted in line with each other, like a bicycle. Measurement data from an accelerometer and agyroscope are used together in a complementary filter for determining the angle from the verticalplane. For balancing, a PID controller was used to control the rotation of a reaction wheel, whenaccelerating causes a straightening torque.

Underlag för bedömning av energibrunnar inom vattenskyddsområde

Denna rapport beskriver arbetet med utvecklingen av en ny modell för kaplanturbiner. Utvecklingen bygger på två kopplade differentialekvationer som under arbetets gång anpassats och implementerats i turbinmodellen.Modellen beskriver hur vattenflöde och turbinmoment påverkas av avvikelsen från den optimala kombineringskurvan för vinklarna på turbinens ledskena och löphjul, och är anpassad för ett referensaggregat med tillgängliga provdata. Även övriga enheter i vattenkraftaggregatet modelleras och sätts samman med frekvensregulator och elnät för att simulera aggregatets reglerstabilitet i önätsdrift.Verifieringen av turbinmodellen sker genom försök att återskapa de befintliga verkningsgradskurvorna med hjälp av modellen. Resultatet visar en god följning av de verkliga kurvformerna, dock med något lägre maximal verkningsgrad.Verifieringen av önätmodellen sker genom att prova stabiliteten i nätfrekvens och turbineffekt vid stegpålastningar. Resultatet ger en stabilare reglerstabilitet än i verkligheten, men uppfyller ändå förväntningarna på en fungerande modell.This report describes the development of a new kaplan turbine model.

Beslutsprocesser i fastighetsbolag vid energiinvesteringar

Municipal Real Estate Companies runs by a political boarder who makes decisions in large investments. In some cases the municipal counter have to take the decisions about big and expensive investments. A successful investment needs to be built on solid ground.Media has lately focused on energy topics as a part of the environmental discussion and the real estate companies tries to use the new technology that the market has provided. Energy investments in new buildings are not longer a small part of the energy saving program. Long-term investment demands needs large knowledge and awareness about the energy topics that have recently grown in the municipal real estate companies.

Dimensionering av industrilager för biobränsle :

The aim of this study was to develop a simple model for calculating stock costs for bio fuel at Billerud Karlsborg and subsequently recommending a suitable stock level of bio fuel. The stock components considered in the model are GROT (branches and tops), bark, dry wood chips, raw wood chips from barking and sawdust. The calculations are based on a probability distribution of historical deviations between ordered and delivered volumes. The model presents two different ways to manage the supply in case of irregular deliveries. The first way is to stock enough volume to cover the deviations and the second way is to compensate with a quick purchase from the spot market (at extra high purchase prices).

Representativa testnät försvenska eldistributionsnät

This project was started within the Market-Design programme of Elforsk, with the aim of developing representative test systems of Swedish distribution networks. Using such test systems as a basis for reliability and customer interruption cost calculations makes it feasible to analyse the network tariff regulation of Swedish power  istribution companies. In particular, it enables studies of the incentives for companies to invest in system reliability. Until now, the available test systems are either not representative of Swedish conditions, or too small in scale and limited in function.Within this project we have created two test systems. In order to represent the diversity of actual Swedish distribution networks, we have created one test system for urban environments and another for rural environments.

Risker i flera dimensioner : Om kopplingen mellan designmönstret MVC och projektrisker

The purpose of this project was to further develop and complete a quadcopter that had been built in an earlier course at KTH, so that it could be used for demonstration and education at the school. The quadcopter was at the beginning of the project completed when it came to hardware, and there was some software functionality implemented but no system for automatic stabilization. The main goal of the project was to implement such a system, and to combine it with the previous functionality to make the quadcopter operable and able to fly. To create a functioning and stable ground multiple basic software features has been implemented, and on top of that additional software to improve the safety, stability and functionality. The most important part is the control system that is responsible for converting sensor and control signals to suitable motor values.

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?.

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