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239 Uppsatser om Stability - Sida 6 av 16
Alternativa dagvattenlösningar för nyexploateringsområden med avseende på substansflöden
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.
Deaktivering av metanisering katalysatorer
A titania-supported nickel catalyst was prepared and tested in methanation in order to evaluate its catalytic properties (activity, selectivity and specially, activity loss), and compare it with an alumina-supported nickel catalyst.The titania-supported catalyst did not only show higher Stability than alumina, but also presented a different cause of deactivation, carbon formation. In addition, a kinetic model was obtained for the titania-supported catalyst, and a study of the effect of different operating conditions (temperature, composition and partial pressures of synthesis gas and water) on the deactivation rate and carbon formation of this catalyst was performed.
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.
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.
Testing and optimization of Unicorn Fluid-Structure Interaction solver for simulating an industrial problem
In industry applications, such as power supply plants, the issue of interaction between fluid and structure is always presented. More precisely, the fluid flow affects the structure by applying force(s) on it and vice versa. As a result, the structure can move (vibrate) or deform. A good understanding of this problem can help to design the system in term of safety, Stability and efficiency.This project aims to optimize and test the Unicorn FSI solver from the FEniCS project [1] to simulate the interaction of fluid and structure in an experiment, which was carried out at Vattenfall Research and Development. The target is to improve the Unicorn FSI solver to cope with a real industrial problem.
Anknytningens förändring och stabilitet i vuxna parrelationer: en integrerad helhetssyn
Several theoretical models of change exist concerning attachment, but an integrated view and knowledge of the role separate factors of change play for the individual is lacking. This phenomenon is hereby studied by semi-structured interviews of 20 persons. Change and factors of change are examined statistically with affectregulation as measure of attachment. The results show that these individuals´ changes are small and mostly towards secure attachment. Metacognition is related to greater change towards secure attachment.
Biogaspotential vid samrötningav mikroalger och blandslam från Västerås kommunala reningsverk
Because of the increasing trends in energy consumption and increased environmental awareness, greater focus has been placed on improvement and development of renewable energy sources. An already proven and accepted method is biogas production from anaerobic digestion at municipal wastewater treatment plants.In the waste water treatment process solid material and dissolved pollutants are separated from the water, forming a sludge. The sludge is separated from the process and stabilized during anaerobic digestion or aerobic aeration. Most often, mesophilic anaerobic digestion is used. Because of degradation by microorganisms, biogas with a high content of methane is formed during the digestion.
Implementering av digitalt vågfilter av Richardstyp i FPGA
Ett digitalt vågfilter av Richardstyp har implementerats i en FPGA på ett utvecklingskort. Sampel kan skickas till filtret och mottas från filtret via serieporten på en dator. Metoden som användes är att en modell av filtret konstruerades i Simulink. Filtret har modifierats med avseende på skalning, brus och stabilitet. VHDL-koden till filtret genererades i Simulink genom att bygga modellen av Xilinx Blockset.
Chalmers University of Technology
The Division of Language and Communication at Chalmers uses a web-based language tool, named EngOnline, to teach English grammar. The language tool suffers from some shortcomings. These include Stability problems and an outdated interface but, above all, there is no documentation. Because of the lack of documentation and EngOnline?s need of maintenance, the Division of Language and Communication has decided to replace the language tool with a new and well documented one.The new language tool was developed using an agile work process; detailed documentation was replaced with more efficient communication.
Utveckling i Latinamerika, En teoriprövande studie med fokus på Costa Rica och Nicaragua
This essay deals with development in Latin America. We have picked out some factors that the theories in development theory emphasize on. The first section of the study consists of a statistical analysis, were the main purposes are to study the relationship between the independent variables and the dependent and to choose which two countries we should focus on in the next section. The countries we decided to study were Costa Rica and Nicaragua, because these countries have shown very different levels of development. From this study we have concluded that political Stability, economical investements and human investments are the most important factors when creating development..
Hållbarhetsredovisning : En branschkartläggning av samhällsansvar
The aim of this study is to look how the Social Service has handled custody issues. The study has a legal and social aspect with a purpose to investigate how the law affects the social administration as well as the family. During a period of one year a quantitative and qualitative study was performed within the social administration in a nearby community. The study focus is partly on the relationship between the law, family and society. The main questions have been: Which one of the parents, mother or father, did in fact get the custody and why? How has the children?s point of view been reported in the inquiry? A child needs a well organized everyday life in a preferably conflict free environment.
Ridningens pedagogik
The purpose of this study has been to look how pedagogic process interacts in horse riding lessons. In order to research this problem I have used an ethnographic approach and during a week I observed ten riding lessons in two separate Riding house in the south of Sweden. In my theoretical frame I have used Michel Foucault ?Discipline and punish? as a toll to make clear how dominance and submission is present and active in the horse riding education.
The conclusion shows how dominant power rules by its presence and creates submission, Stability and feeling of security. The discipline is used to create a feeling that will bring the riders to new experience and develop their talent.
Utveckling av reglersystem till quadrokopter
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.
Hur sker utvecklingen i Bosnien? : En studie om nationsbyggandet i Bosnien och Hercegovina ? utifra?n tre perspektiv.
Nation building is vital in post-war states to bring the people that have been at war together. To restore peace in a state, many different actors need to work together to bring Stability, safety, and advancement to a new nation. There are several methods of nation building, and this thesis evolves around three of them. This is a qualitative study where three theories on nation building are used to analyze the development of nation building, and the obstacles Bosnia and Herzegovina still has to reach a national identity. Several studies are used in this thesis to show how the development has evolved in Bosnia and Herzegovina.