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261 Uppsatser om Sliding stability - Sida 3 av 18

Hisskärna av skalväggar i höga byggnader : Ett alternativ till den platsgjutna kärnan

A common way to stabilize high rise buildings is to use an elevator core built of concrete. Today, we use to build these elevator cores of in-situ concrete. Precast concrete twin wall (double wall) is a semi-finished product that has become more common in recent years. This diploma work studies how the twin wall works out as structural elements in an elevator core. The work also shows some possible ways of designing twin walls and highlights some important parts of the design that will be vital to the stability of the building.    The result shows that it is important to think through where the element joints should be placed.

DESIGN AV ALUTON 38? FRAKTBÅT FÖR KUSTNÄRA TRANSPORTER

This master thesis is about designing and dimensioning a boat for transport of caravan, car, trailer or ATV. Buoyancy and stability are important properties as the pontoonboat should also be able to serve as a workboat. Many of the vessels on the market today that is being used for similar purpose are stable enough, but their hull is often similar with barges and thus too slow. This work has been to construct a boat that has good stability but also has a hull that enables it to move faster, is more maneuverable and having a more attracting design than today?s barges.

Förbättrad förbränningsstabilitet i EBK för turbofläktmotor RM12 genom förändrad motorreglering : Improved afterburner combustion stability for turbofan engine RM12 by modified engine control

The engine of JAS 39 Gripen, RM12, has recently been equipped with a new flameholder and a new engine inlet. This change has caused an increased noise level from the engine when the afterburner is in use. The noise level reaches its peak when the afterburner is partially used. The problem is thought to be unstable combustion in the regions around the flameholder. A solution to the problem has been proposed by Volvo Aero.

Inhysningssystem för tjurar : fallstudie

It´s important when you are about to build a new stable or just increasing your production that you choose the right housing system and that it fits your own farm. In this study I have put together facts about different housing system for fattening bulls in order to get a clearer picture of witch system is the most suitable for my own farm depending on the conditions I have. The background of this work is my own interest for breeding bulls and I will hopefully increase my own production. Due to this I wanted to learn more and increase my knowledge about different housing systems. Through a literature study I have found out the facts about the housing systems I find suitable for housing bulls.

Storage stability in a milk based UHT-beverage : effect of pH, carrageenan and storage time

The different characteristics of many food products, such as aroma and texture, changes during storage time and become undesirable. The reason is instabilities within the product which become prominent as the product ages. These changes in characteristics are quality losses caused by changes in the product?s intrinsic and extrinsic environment. The stability in UHT-milk and beverages similar to it have been studied in the past decades and a certain focus have been on age gelation which is a common defect in these type of products.

Ethnicity and Politics of Exclusion in Nigeria : Employing Rawls'Theory of Justice in Plural Societies

With an estimated 250 ethnic groups, Nigeria, no doubt, has been grappling with the problem of pluralism of ethnic nationalities. It is not news in Nigeria that extreme ethnic consciousness of its citizens has led to the victimization of one ethnic group by another. This victimization has come in the form of exclusions in the distribution of both wealth and power in the country.Amidst all the exclusions, the unity of the country has been ironically regarded as sacrosanct, and should not be negotiated. It is often said that fate brought all the ethnic nationalities in order to form one great country. I subscribe to this belief that fate brought us together for the above purpose, especially now that several countries around the world are merging in one way or the other to form a formidable force to reckon with both politically and economically.

Utvärdering av en ny selektionsmetod för hingstsperma : med avseende på membranintegriteten och membranstabiliteten

Today, equine breeding is based on performance and conformation, resulting in a vast variation in fertility among different horses, with noticeable economic losses as a consequence. The horse breeding industry is therefore in need of methods that diagnose the spermatozoa concerning their quality and provide the best sperm for AI. The commonly used selection methods for sperm today are: centrifugation, where extender is added, the sample is centrifuged and then resuspended; swim-up self-migration; adherence separation; and density gradient centrifugation. However, none of these methods are in used routinely in practice before inseminating mares with fresh or cooled semen. The aim of this study was to evaluate a new selection method, Single Layer Centrifugation (SLC), and its effect on sperm viability. The viability was analyzed with regard to membrane integrity and membrane stability of ejaculated spermatozoa.

EU:s grannskapspolitik i Medelhavsregionen : En säkerhetspolitisk analys av Medelhavssamarbetet

AbstractThe thesis investigates how the European Union promotes stability and security in the Mediterranean region. The aim is to analyse the European Union?s security ambitions with Euro-Mediterranean Partnership, the Barcelona Process. An analytical framework with five sectors (military, political, economic, environmental and societal), based on the Copenhagen School?s theories about security sectors and securitization, is used for the analysis.

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.

Aggregatstabilitet, jordbearbetning och fosforförluster i ett typområde på jordbruksmark :

Large amounts of phosphorus (P) are lost from the arable land due to water erosion. Both phosphorus attached to particles and dissolved phosphorus (mainly phosphate) are transported away with drainage-water and surface runoff. Good soil structure is important in minimizing these losses. In this study, soils from 50 fields were analysed with respect to aggregate stability as measured by dispersion of clay together with the content of total phosphorus (TotP), particulate phosphorus (PP) and phosphate phosphorus (PO4P) in the water phase. All soils were clay soils with clay content varying between 21 and 54%.

Självförsörjande elgenerering : Kan Orust bli självförsörjande på förnybar el?

Orust Kretsloppsakademi is a nonprofit organisation, with a goal of annually generate the same amount of electrical energy that is consumed. Orust is an island on the west coast of Sweden, north of Gothenburg. The population of 15 000 reaches 40 000 during summer, due to the large amount of vacationer. The total electricity demand is 174 GWh a year with a maximum power need of 32 MW. This report presents an analysis for the plausibility of their plan and from a power system stability perspective, the effects on the electrical grid.The conclusion is that the restraints for development of power generation from wind, solar and wave generation, are the power systems capability to transfer power, primarily in the transformers of the grid.

Frekvensreglering i det nordiska kraftsystemet

Svenska Kraftnät is (together with the other transmission system operators of the Nordic power system) responsible for keeping balance between the generated and demanded power in the Nordic power system. Spontaneous load variations and system disturbances, however, lead to power imbalance followed by frequency variations. The frequency deviations can be limited to an acceptable level by the spinning reserve, mainly by hydro power control. But there are also other system properties which have a great influence on the frequency and system stability. The frequency and voltage dependence of the loads have a direct influence on the power balance.

Towards a function for an Arabidopsis protein involved in sucrose dynamics

System based models of plants rely on descriptions and assigned functions of genes, and currently 50% of the genes in Arabidopsis thaliana has either no assigned function or a function based on homology only. Mitogen activated protein kinases (MAPK's) are key players in cell signalling and are conserved among eukaryotes, though their targets are highly diverse. A recent study has described a small Arabidopsis protein (80), without homology to any described protein, as a phosphorylation target of the MAPK's MPK3/6. Further work established ?-glucan phosphorylase (PHS) as interacting with 80 and described a delayed senescence phenotype for 80 knock-out plants.

Artificiella neurala nätverk som lösning på segmenteringsproblemet vid gestigenkänning

Ett av de stora problemen med gestigenkänning är det som kallas segmenteringsproblemet. Segmenteringsproblemet är problemet att hitta var en gest börjar och var den slutar, d v s att segmentera upp gester. I detta arbete testas en lösning till detta problem då gester består av figurer ritade i luften. Lösningen går ut på att använda två stycken artificiella neurala nätverk av strukturen FeedForward. Det ena nätverket tränas på att känna igen när handen accelererar från stillastående, vilket representerar starten av en gest, och det andra tränas på att känna igen när handen saktar ner till stillastående, vilket representerar slutet av en gest.

Konstruktion av turbinmodell för kaplanturbiner

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.

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