Information-Theoretic Approach for Path Planning of a Moving Platform with Bearings-only Sensor

Using flying vehicles for reconnaissance and surveillance has always been interesting, especially in military applications. Unmanned aerial vehicles (UAVs) have been increasingly used in the last decades, but they have often been controlled by an operator on the ground. In an attempt towards higher level of autonomy, the UAV should be able to decide itself where to fly. This thesis examines a method for autonomous path planning based on the uncertainty of the target locations, a so called information-theoretic approach. A bearings-only sensor is attached to the UAV, such as a video or an infrared sensor, which makes observations of the relative angle to the object, reducing the uncertainty orthogonal to the observed target. The planned path is the solution to an optimization problem, such that the uncertainty is minimized which is equal to maximizing the information in the information-theoretic approach. When identifying a target, there is a potential benefit to make observations from different views. If the path could be planned, the better are the observations of the target, and the image based identification will be more reliable to target appearance variations and more robust against decoys

Outsourcing - Projektutvärdering över tiden

Syfte: Syftet med uppsatsen är att undersöka hur ansvariga personer för företagens outsourcingsprojekt utvärderar outsourcingen och om dess kriterier ändras under projekttiden. Metod: Abduktiv metod med främst kvalitativ datainsamling genom intervjuer. Slutsats: Det dominerande motivet bakom outsourcingen för de undersökta företagen är kostnadsbesparing. I början av projektet och vid leverantörsvalet undersöks också detta motiv. Under projektets gång utvärderas det som specificerades i avtalet mellan företaget och leverantören, vilket är mest mätbara kvalitetspunkter och fokus har därmed skiftat från det ursprungliga motivet

Comparative study: the effect of annealing conditions on the properties of P3HT:PCBM blends

This paper presents a detailed study on the role of various annealing treatments on organic poly(3-hexylthiophene) and [6]-phenyl-C61-butyric acid methyl ester blends under different experimental conditions. A combination of analytical tools is used to study the alteration of the phase separation, structure and photovoltaic properties of the P3HT:PCBM blend during the annealing process. Results showed that the thermal annealing yields PCBM ‘‘needle-like’’ crystals and that prolonged heat treatment leads to extensive phase separation, as demonstrated by the growth in the size and quantity of PCBM crystals. The substrate annealing method demonstrated an optimal morphology by eradicating and suppressing the formation of fullerene clusters across the film, resulting in longer P3HT fibrils with smaller diameter. Improved optical constants, PL quenching and a decrease in the P3HT optical bad-gap were demonstrated for the substrate annealed films due to the limited diffusion of the PCBM molecules. An effective strategy for determining an optimized morphology through substrate annealing treatment is therefore revealed for improved device efficiency.Web of Scienc

Morphology studies of thin films of polyfluorene: fullerene blends

The formation of thin films of polymer blends by spin-coating from solution is characterised by rapid solvent quenching, a process that results in non-equilibrium morphologies. Thin films of conjugated polymer blends are used as the active material in polymer solar cells, in which the morphology may have drastic effects on device performance. In this thesis results from morphology studies are presented for spin-coated thin films of polyfluorenes and co-polymers of polyfluorene blended with the fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester (PCBM). The surface morphology was investigated by atomic force microscopy (AFM) and was found to depend on the blend ratio as well as the chemical structure of the blend components. The spin speed, which determines the thickness of the spin-coated thin films, was also found to influence the morphology. Secondary ion mass spectrometry (SIMS) was used for depth profiling of the chemical composition in thin films of poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-5,5-(4´,7´-di-2-thienyl-2´,1´,3´-benzothiadiazole)] (LBPF5) blended with PCBM. The films were found to be vertically phase separated with a four-fold multilayered structure

Det omedvetnas inverkan på lärande i arbetslivet : tolkat utifrån Paul Moxnes teori om djuproller

Bakgrund: I arbetslivet påverkas vi av omedvetna krafter som förekommer oss emellan. I uppsatsen gestaltas dessa omedvetna krafter utifrån Paul Moxnes teori om djuproller. Teorin om djuproller bygger på Jungs tanke om det arketypiska som finns i allas vårt omedvetna. Djuprollerna innebär i korthet att vi omedvetet tillskriver varandra olika roller som vi omedvetet lever upp till. Min föreställning var att detta inverkar på vårt sätt att lära på arbetsplatsen. Syfte: Syftet med uppsatsen är att diskutera hur det omedvetna - djuprollerna - inverkar på lärande i arbetslivet. Metod: En litteraturstudie har genomförts. För att synliggöra det omedvetna har fallet AB Superglas får ny ledare använts som är en fiktiv berättelse om en organisation i förändring. Resultat: AB Superglas får ny ledare visade att medarbetarna inom en arbetsorganisation omedvetet tilldelar varandra olika roller, vilket inverkar på arbetsorganisationens lärande. I AB Superglas fall skapar djuprollerna ett lärande som snarare är av hämmande än utvecklingsinriktad art. De motkrafter som finns mot personlig utveckling finns ofta mellan oss själva. Vår självuppfattning grundas många gånger på hur andra ser på oss på ett mer eller mindre medvetet plan. Djuprollerna kan därför ge bättre förståelse för olika beteendemönster och omedvetna skeenden som förekommer på arbetsplatsen och kan därmed utgöra en förklarningsmodell till varför vi lär som vi gör. Nyckelord: Det omedvetna, djuproller, arketyper, omedvetet lärande

Thin films of polyfluorene:fullerene blends - Morphology and its role in solar cell performance

The sun provides us daily with large quantities of energy in the form of light. With the world’s increasing demand of electrical energy the prospect of converting this solar light into electricity is highly tempting. In the strive towards mass-production and low cost solar cells, new types of solar cells are being developed, e.g. solar cells completely based on organic molecules and polymers. These materials offer a promising potential of low cost and large scale manufacturing and have the additional advantage that they can be produced on flexible and light weight substrate which opens for new and innovating application areas, e.g. integration with paper or textiles, or as building materials. In polymer solar cells a combination of two materials are used, an electron donor and an electron acceptor. The three dimensional distribution of the donor and acceptor in the active layer of the device, i.e. the morphology, is known to have larger influence of the solar cell performance. For the optimal morphology there is a trade-off between sometimes conflicting criteria for the various steps of the energy conversion process. The dissociation of photogenerated excitons takes place at an interface between the donor and acceptor materials. Therefore an efficient generation of charges requires a large interface between the two components. However, for charge transport and collection at the electrodes, continuous pathways for the charges to the electrodes are required. In this thesis, results from morphology studies by atomic force microscopy (AFM) and dynamic secondary ion mass spectrometry (SIMS) of spin-coated blend and bilayer thin films of polyfluorene co-polymers, especially poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-5,5-(4´,7´-di-2-thienyl-2´,1´,3´-benzothiadiazole)] APFO-3, and the fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) are presented. It is shown that by varying the blend ratio, the spin.-coating solvent, and/or the substrate, different morphologies can be obtained, e.g. diffuse bilayer structures, spontaneously formed multilayer structures and homogeneous blends. The connection between these different morphologies and the performance of solar cells is also analysed. The results indicate that nano-scale engineering of the morphology in the active layer may be an important factor in the optimization of the performance of polymer solar cells

Thin films of polyfluorene:fullerene blends - Morphology and its role in solar cell performance

The sun provides us daily with large quantities of energy in the form of light. With the world’s increasing demand of electrical energy the prospect of converting this solar light into electricity is highly tempting. In the strive towards mass-production and low cost solar cells, new types of solar cells are being developed, e.g. solar cells completely based on organic molecules and polymers. These materials offer a promising potential of low cost and large scale manufacturing and have the additional advantage that they can be produced on flexible and light weight substrate which opens for new and innovating application areas, e.g. integration with paper or textiles, or as building materials. In polymer solar cells a combination of two materials are used, an electron donor and an electron acceptor. The three dimensional distribution of the donor and acceptor in the active layer of the device, i.e. the morphology, is known to have larger influence of the solar cell performance. For the optimal morphology there is a trade-off between sometimes conflicting criteria for the various steps of the energy conversion process. The dissociation of photogenerated excitons takes place at an interface between the donor and acceptor materials. Therefore an efficient generation of charges requires a large interface between the two components. However, for charge transport and collection at the electrodes, continuous pathways for the charges to the electrodes are required. In this thesis, results from morphology studies by atomic force microscopy (AFM) and dynamic secondary ion mass spectrometry (SIMS) of spin-coated blend and bilayer thin films of polyfluorene co-polymers, especially poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-5,5-(4´,7´-di-2-thienyl-2´,1´,3´-benzothiadiazole)] APFO-3, and the fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) are presented. It is shown that by varying the blend ratio, the spin.-coating solvent, and/or the substrate, different morphologies can be obtained, e.g. diffuse bilayer structures, spontaneously formed multilayer structures and homogeneous blends. The connection between these different morphologies and the performance of solar cells is also analysed. The results indicate that nano-scale engineering of the morphology in the active layer may be an important factor in the optimization of the performance of polymer solar cells

Polymer blends spin-cast into films with complementary elements for electronics and biotechnology

Versatility of solution-processing strategy based on the simultaneous rather than additive deposition of different functional molecules is discussed. It is shown that spin-cast polymer blends result in films with domains that could form elements with complementary functions of (i) solar cells, (ii) electronic circuitries, and (iii) test plates for protein micro-arrays: Alternating layers, rich in electron-donating polyfluorene and electron-accepting fullerene derivative, result in optimized solar power conversion. Surface patterns, made by soft lithography, align conductive paths of conjugated poly(3-alkylthiophene) in dielectric polystyrene. Proteins, preserving their biologically activity, are adsorbed to hydrophobic domains of polystyrene in hydrophilic matrix of poly(ethylene oxide). The authors report the research progress on structure formation in three polymer blend families, resulting in films with complementary elements for electronics and biotechnology. Blend film structures are determined with secondary ion mass spectrometry, atomic force microscopy, and fluorescence microscopy. In addition, the authors present recent results on (i) structure formation in fullerene derivative/poly(3-alkylthiophene) blends intended for solar cells, (ii) 3-dimensional SIMS imaging of conductive paths of poly(3-alkylthiophene) in dielectric polystyrene, (iii) test plates for multiprotein micro-arrays fabricated with blend films of hydrophobic polystyrene and thermoresponsive poly(N-isopropylacrylamide)