Sök:

Sökresultat:

115 Uppsatser om Physics and Astronomy - Sida 6 av 8

Isaac Newton och den matematiska naturfilosofin

In several scientific and technical educations today we meet mathematical studies in differential- and integral calculus. The classic mechanics is a foundation for the physics and it has made it possible for today's technical developments that we in our everyday life meet and make use of. The intention for this essay is to give a picture of the person behind this discoveries that changed the science and the world. Besides the purpose to bring the reader on a journey through Isaac Newton's life the main intention is to give an understanding of the way he discovered the binomial theorem, the differential- and integral calculus, the numerical methods Newton-Raphson's and Newton's interpolation-polynomial, Newtons identities and his classification of third-degree curves and elliptic curves. A derivation of Kepler's first law is also included..

Konstruktion av upprätningssystem för CICLoPE

Today there is no way of measuring or simulating turbulent flow in high Reynolds numberenvironments. The computational power required to simulate these conditions is not expectedto be available for several decades so instead the CICLoPE project aims at solving thisshortage by the construction of a long carbon fiber wind tunnel in which real measurementscan be made. To do accurate measurements it is of importance that the wind tunnel, 0.9 metersin diameter and 110 meters long, is as straight as possible.This master thesis treat the design and construction of a device which may be used to align thetunnel along a reference laser beam. A design is presented which allows the pipe to be alignedwithin about a quarter of a millimeter along its entire length. Contents span over severalscience fields such as physics, mechanics, control theory and electronics.The result is a theoretically correct design.

Reciprok egoism, skeptisk empirism och modern fysikalism : Titelförslag på några principer och diskurs kring dessas korrelation

Denna essä är en ontologisk och epistemologisk undersökning av bland annat etiska och medvetandefilosofiska implikationer av en konsekvent fysikalistisk hållning. I detta kontrasteras mot en transcendentalistisk hållning, som den av T. M. Scanlon, den skeptiska empirismen av David Hume, reciprokt baserade moraliska system (e.g. J. L.

Förbränning av träpellets och pelleterad halm i en 40 kW rosterreaktor

The project focus on combustion of softwood pellets and pellets in a 40 kW grate fire reactor at TEC-Lab. Dept Applied Physics and Electronics at Umeå University. Experiments were performed at four primary airs to fuel ratios (0.7 to 1.3), where aspects such as temperature profile, levels of gases (CO and NO), sintering-/-slagging and unburned fraction of the ashes were studied. Four different fuel loads were used for wood pellets (10, 20 and 30 kW) and one fuel load for straw (10 kW). Combustion of straw proved very difficult to ignite, and also led to other combustion-related technical problem such as slag formation due to the relatively low melting temperature-/-slag temperature of the straw.

Astronomins intellektuella bas 1999 - 2013 : En författarcociteringsanalys av fältet astronomi

Kontext: I denna uppsats kartlades den intellektuella basen i forskningsfältet astronomi. Mål: Syftet med denna uppsats var att studera strukturella förändringar som skett i det vetenskapliga fältet astronomi mellan 1999 och 2013 och identifiera dess specialområden. Metod: Syftet uppfylldes med tre författarcociteringsanalyser, en för perioden 1999-2003, en för 2004-2008 och den sista för åren 2009-2013. Totalt hämtades 94642 artiklar för analys från de fem core-tidskrifterna Astrophysical Journal, Astronomical Journal, Montly Notices of the Royal Astronomical Society, Astronomy and Astrophysics och Publications of the Astronomical Society of the Pacific mellan åren 1999 och 2013. Resultat: De visade sig att de största specialområdena i astronomins intellektuella bas tillhörde kosmologin.

Computer Modelling of the Influence of Surface Topography on Water Repellency and a Study on Hydrophobic Paper Surfaces with Partly Controlled Roughness

A computer model based on minimization of the free energy, capable to predict contact angles and spreading transitions between Wenzel and Cassie mode for drops placed on surfaces with different topography were implemented in matlab. Simulations were compared with experiments documented in the literature. These showed that reported transitions between Cassie and Wenzel mode can be explained by minimization of the free energy. In this report, a study on the possibility of constructing water repellent paper surfaces with a combination of treatment with octadecyltrichlorosilane and topography changes, is included..

Tidsberoende kvantkemiska beräkningar av optisk absorption hos polymerer och molekyler med litet bandgap

The vertical electronic excitation energies for the narrow-bandgap polymers LBPF, EP37 and EP62 have been calculated using Density Functional Theory (DFT). Also the vertical excitation energies for the acceptor unit of LBPF have been calculated using the Hartree-Fock (HF), DFT and Coupled Cluster (CC) methods. The calculations cover the visible and infrared wave length region and two strong transitions are obtained, one corresponding to the pi to pi* transition and one corresponding to the pi to Acceptor transition. The excitation energies obtained from DFT are below the corresponding experimental results and attempts have therefore been made to perform bench-marking calculations using a hierarchy of CC methods..

Barns föreställningar om dag- och nattcykeln : Har eleverna uppnått målen för år 5?

Syftet med detta examensarbete är att ta reda på hur elevers uppfattningar om de rörelser som sker i vårt solsystem stämmer överens med de vetenskapliga fakta som finns. I våra vardagliga situationer refererar vi till det vi med ögats hjälp kan uppfatta i fråga om vad som rör sig eller ej. Hur påverkas eleverna av de dagliga uttryck som de får höra sedan de är mycket små, och har de en möjlighet att med skolans hjälp förändra dessa tankesätt?Undersökningen genomfördes med hjälp av kvalitativa intervjuer av elever i skolår 1 respektive 5. Detta för att se hur stor skillnaden är mellan de elever som inte har erhållit någon undervisning om solsystemet och de elever som ska ha uppnått de mål för fysik som skolverket har ställt upp.Eleverna som deltog i studien valdes slumpmässigt ur respektive klasser.

Sputtring av Ti-Si-C-Ag beläggningar från sammansatta sputterkällor

Idag används guld som kontaktmaterial på elektriska kontakter för lågströmstillämpningar. Guldhar emellertid låg nötningsbeständighet, är dyrt och miljömässigt påfrestande att utvinna. Ettalternativt kontaktmaterial till guld är nanokomposit Ti-Si-C-Ag belagt medlikströmsmagnetronsputtring. Nanokomposit Ti-Si-C-Ag har hittills belagts med sammansatt Ti-Si-C sputterkälla och separat silverkälla.I detta arbete har filmer belagts från tre olika sammansatta Ti-Si-C-Ag-källor med tre olikakolhalter. Filmerna har belagts i två olika beläggningssystem: Ett konventionellt batchladdat ochett sekventiellt med sluss.Filmernas fas- och ämnessammansättning har studerats med XRD och EDX.

En kvalitativ undersökning om mobbning : En studie om skillnader och likheter mellan organisationen Friends och skolans arbetsmetod att motverka mobbning

This qualitative study is about the differences and similarities between the organization Friends and schools? methods to prevent bullying. Aggression, bullying and discomfort in schools result in that many students do not dare to go to school because of their fear that they might get attacked and become systematically bullied. Bullying is a universal and persistent problem. In this study the reader will receive a better understanding and get an insight into the problems that teachers and students experience and struggle with every day in dealing with bullying in schools.

The Nature and Role of Experiment in Science Education

Experimentets art och roll i naturvetenskaplig undervisning är ett fundamentalt och omfattande ämne. I föreliggande litteraturstudie görs ett försök att sätta in frågan i ett historiskt, pedagogiskt och vetenskapligt sammanhang. Innan experimentets roll diskuteras, ställs dock frågan vad naturvetenskap är, varför och hur det skall undervisas, och vad som kännetecknar praktiskt arbete och experimentell verksamhet i skolan. Med denna bakgrund refereras några forskares och lärares erfarenheter och åsikter. Det visar sig, föga överraskande, att formerna för och avsikterna med experiment i undervisningen är skiftande.

En studie om vilkenundervisningsmetod som ger störst inlärningseffekt hos barn : En jämförelse av kunskapstest före respektive efter undervisning

The aim of this thesis is to study the teaching methods that provide the greatest learning effect for children in grades 6 in the subject of physics. One class was divided into three equal groups, each group was educated in a specific way. The three teaching methods that have been investigated are: film with reflection, laboratory work and traditional lecture- teaching. The research question of the study is: "Which method of three selected, causes the greatest understanding of the properties of air??.

Kampen om Piteå handelshamn 1950 - 1973 : från lokal stadshamn till nationell handelshamn

Survey's purpose is to illustrate why and how the process happened when Piteå relocated its commercial port away from Skuthamn to the new construction on Haraholmen 1950-1973. How decision-makers worked to achieve their goals, how the work changed and what incentives motivated them to act. The results showed that the decision was taken not to retain the existing commercial port in large part due to Skuthamns physics attributes, which made it impossible to ship large deep vessels from there. The reason that the decision about the port took such a long time was due to a local political conflict which was based on interest in the ownership of Haraholmen. The reason for the location of the trading port became Haraholmen had political backgrounds.

OLED : Evaluation and clarification of the new Organic Light Emitting Display technology

Organic Light Emitting Displays (OLEDs) are a new type of thin emissive displays predicted to possess superior properties to existing techniques e.g. Liquid Crystal Display (LCD). The main advantages are low power consumption and a thin display structure. This report contains an explanation of the emissive OLED technology, its functionality and the physics of the organic layer structure in an OLED. The technology is described with respect to the two classes of organic materials used in displays, small molecules and conjugated polymers.

Enkla kemiska processer inom förskolan : En kvalitativ intervjustudie om förskollärares uppfattningar och tankar om läroplansmålet enkla kemiska processer

The aim of this study was to investigate preschool teacher?s perceptions about the curriculum goal concerning simple chemical processes. The result was based on narratives received by a qualitative study and semi-structured interviews of six preschool teachers. The results of the study showed that preschool teachers perceive that they actually are working in a relatively small scale with simple chemical processes and they do not really know what simple chemical processes are, and do not feel very familiar with the subject. Water, dough, mud, paint and baking were the most common activities that were used when working towards the curricular goal. However, it was never explained to the children that it was simple chemical processes they were working with during the activities, neither was it discussed among colleagues because of the uncertainty about the concept.

<- Föregående sida 6 Nästa sida ->