In this thesis, a block-based motion estimation algorithm suitable for Super-Resolution (SR) image reconstruction is introduced. The motion estimation problem is formulated as an energy minimization problem that consists of both a data and regularization term. To handle cases when motion estimation fails, a block-based validity method is introduced, and is shown to outperform all other validity methods in the literature in terms of hybrid de-interlacing. By combining the validity metric into the energy minimization framework, it is shown that 1) the motion vector error is made less sensitive to block size, 2) a more uniform distribution of motion-compensated blocks results, and 3) the overall motion vector error is reduced. The final motion estimation algorithm is shown to outperform several state-of-the-art motion estimation algorithms in terms of both endpoint error and interpolation error, and is one of the fastest algorithms in the Middlebury benchmark. With the new motion estimation algorithm and validity metric, it is shown that artifacts are virtually eliminated from the POCS-based reconstruction of the high-resolution image.

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På överhettartuber i värmepannor bildas beläggningar på grund av sot och partiklar från förbränningen. Beläggningarna isolerar överhettartuberna vilket försämrar värmepannans verkningsgrad. Sotning av tuberna sker under drift och ett system som automatiskt kan beräkna hur mycket beläggningar som finns på tuberna skulle kunna göra sotningen mer behovsstyrd.Resonansfrekvenser hos överhettartuberna påverkas av masspåslaget som blir när beläggningar bildas. En förändring i frekvens kan då översättas till en förändring i massa. Vibrationsmätningar har gjorts med töjningsgivare som är monterade på överhettartuber i en av Ryaverkets pannor och i SAKAB:s panna. I detta examensarbete har syftet varit att analysera olika metoder för att skatta resonansfrekvenser i genomförda mätningar. Algoritmerna MUSIC, ESPRIT och AR samt en heuristisk statistisk metod har testats på genererade signaler. MUSIC och ESPRIT har givit bäst skattningar och har därefter använts för att analysera mätningarna. Periodvis följer vissa skattningar av mätningar från Ryaverket trender mellan sotningarna vilket indikerar att det skulle kunna vara resonansfrekvenser. Annars innehåller skattningarna för mycket variationer. Skattningarna av mätningar från SAKAB:s panna är gjorda under en kortare tidsperiod men visar en tydligare trend som troliggör att det är resonansfrekvenser som detekterats.För att automatiskt hitta och följa resonansfrekvenser i skattningarna, även om dessa innehåller stora variationer, har en målföljningsalgoritm implementerats. Algoritmen hittar skattningar som följer en förväntad trend mellan sotningarna. Tester visar att algoritmen hittar troliga resonansfrekvenser i skattningarna men att det är svårt att kunna dra några slutsatser om skattningarna varierar för mycket. Bättre signaler skulle kunna minska variationerna hos skattningarna. Ett förslag presenteras hur MUSIC eller ESPRIT tillsammans med en målföljningsalgoritm skulle kunna användas för att beräkna masspåslag på överhettartuberna. / Combustion in thermal power plants emits particles which create coatings on the super heater tubes. The coatings insulate the tubes and impairs the efficiency of the heat transfer. Cleaning the tubes occurs while the power plant is running and a system that automatically calculates the amount of coatings could make the cleaning more needs-based. The resonance frequencies of the super heater tubes are affected by the added mass of the coatings. A change in frequency corresponds to a change in mass. Vibration measurements have been made with strain gauges on the super heater tubes in Ryaverket's power plant and in one of SAKAB's power plants. The purpose of this thesis work has been to analyse different methods to estimate resonance frequencies in the vibration measurements. ESPRIT, MUSIC, AR and a heuristic statistical method have been tested on generated signals. MUSIC and ESPRIT have given the best estimations and have thus been used to analyse the measurements. Periodically some estimations of measurements from Ryaverket are following trends which indicates that they could be resonance frequencies. The rest of the estimations contain too large variations. The estimations made of the measurements from SAKAB have been made during a shorter time period but shows clearer trends which make them probable resonance frequencies.To automatically trace resonance frequencies in the estimations, even though they contains large variations, a target tracking algorithm has been implemented. The algorithm finds estimations that follows expected trends between the cleaning periods. Tests shows that the target tracking algorithm finds probable resonance frequencies in the estimations but that it is hard to reach a conclusion if they contain large variations. Better measurements could give estimations with smaller variations.An idea is presented where MUSIC or ESPRIT together with a target tracking algorithm could be used to calculate the amount of coatings on the super heater tubes.

This Master Thesis has been conducted at the National Laboratory of Forensic Science (SKL) in Linköping. When images that are to be analyzed at SKL, presenting an interesting object, are of bad quality there may be a need to enhance them. If several images with the object are available, the total amount of information can be used in order to estimate one single enhanced image. A program to do this has been developed by studying methods for image registration and high resolution image estimation. Tests of important parts of the procedure have been conducted. The final results are satisfying and the key to a good high resolution image seems to be the precision of the image registration. Improvements of this part may lead to even better results. More suggestions for further improvementshave been proposed. / Detta examensarbete har utförts på uppdrag av Statens Kriminaltekniska Laboratorium (SKL) i Linköping. Då bilder av ett intressant objekt som ska analyseras på SKL ibland är av dålig kvalitet finns det behov av att förbättra dessa. Om ett flertal bilder på objektet finns tillgängliga kan den totala informationen fråndessa användas för att skatta en enda förbättrad bild. Ett program för att göra detta har utvecklats genom studier av metoder för bildregistrering och skapande av högupplöst bild. Tester av viktiga delar i proceduren har genomförts. De slutgiltiga resultaten är goda och nyckeln till en bra högupplöst bild verkar ligga i precisionen för bildregistreringen. Genom att förbättra denna del kan troligtvis ännu bättre resultat fås. Även andra förslag till förbättringar har lagts fram.

Background: Along with the rapid economic development in China, some associatingproblems emerged, such as inflation. Especially for the daily consuming fresh fruits andvegetables (FFV), the price goes up at very fast speed, which draws a lot of publicattention on it. Farmers are discouraged and hurt by the low vegetable prices. However,end consumers are complaining about the high vegetable prices. A consensus is reachedthat the problem behind this phenomenon exists in the "distribution links".Aim: How is the current status of FFV distribution system of supermarkets in China?What factors do influence the efficiency and cost of the system? How is theimplementation of ASD in China and what are the advantages and barriers? Should it beimplemented widely? If yes, what are our recommendations to improve it?Definition: Agricultural super-docking is a new method of supply and distribution offresh agricultural products from farmers to supermarkets directly, by signing anagreement of intent between farmers and merchants, in order to build an efficientplatform for quality agricultural products to enter the supermarkets. The essence of ASDis to dock the thousands of small farmers and the different supermarkets to build anintegrated production and marketing chain to gain benefit for merchants, farmers andconsumers at the same time.Completion and results: It is a complex task to improve the efficiency of FFVdistribution system of supermarkets in China and there is a long way to go to implementASD successfully and widely since this market is at the starting stage and immature. Toimplement ASD successfully and widely, professional FFV third-party distributioncenters should be constructed, as well as exchanging information norm.

The rapid air travel growth during the last three decades, has resulted in runway congestion at major airports. The current airports infrastructure will not be able to support the rapid growth trends expected in the next decade. Changes or upgrades in infrastructure alone would not be able to satisfy the growth requirements, and new airplane concepts such as the NASA proposed Super Short Takeo and Landing and Extremely Short Takeo and Landing (ESTOL) are being vigorously pursued. Aircraft noise pollution during Takeoff and Landing is another serious concern and efforts are aimed to reduce the airframe noise produced by Conventional High Lift Devices during Takeoff and Landing. Circulation control technology has the prospect of being a good alternative to resolve both the aforesaid issues. Circulation control airfoils are not only capable of producing very high values of lift (Cl values in excess of 8.0) at zero degree angle of attack, but also eliminate the noise generated by the conventional high lift devices and their associated weight penalty as well as their complex operation and storage. This will ensure not only satisfying the small takeoff and landing distances, but minimal acoustic signature in accordance with FAA requirements. The Circulation Control relies on the tendency of an emanating wall jet to independently control the circulation and lift on an airfoil. Unlike, conventional airfoil where rear stagnation point is located at the sharp trailing edge, circulation control airfoils possess a round trailing edge, therefore the rear stagnation point is free to move. The location of rear stagnation point is controlled by the blown jet momentum. This provides a secondary control in the form of jet momentum with which the lift generated can be controlled rather the only available control of incidence (angle of attack) in case of conventional airfoils. The use of Circulation control despite its promising potential has been limited only to research applications due to the lack of a simple prediction capability. This research effort was focused on the creation of a rapid prediction capability of Circulation Control Aerodynamic Characteristics which could help designers with rapid performance estimates for design space exploration. A morphological matrix was created with the available set of options which could be chosen to create this prediction capability starting with purely analytical physics based modeling to high fidelity CFD codes. Based on the available constraints, and desired accuracy metamodels has been created around the two dimensional circulation control performance results computed using Navier Stokes Equations (Computational Fluid Dynamics). DSS2, a two dimensional RANS code written by Professor Lakshmi Sankar was utilized for circulation control airfoil characteristics. The CFD code was first applied to the NCCR 1510-7607N airfoil to validate the model with available experimental results. It was then applied to compute the results of a fractional factorial design of experiments array. Metamodels were formulated using the neural networks to the results obtained from the Design of Experiments. Additional validation runs were performed to validate the model predictions. Metamodels are not only capable of rapid performance prediction, but also help generate the relation trends of response matrices with control variables and capture the complex interactions between control variables. Quantitative as well as qualitative assessments of results were performed by computation of aerodynamic forces and moments and flow field visualizations. Wing characteristics in three dimensions were obtained by integration over the whole wing using Prandtl's Wing Theory. The baseline Super STOL configuration was then analyzed with the application of circulation control technology. The desired values of lift and drag to achieve the target values of Takeoff and Landing performance were compared with the optimal configurations obtained by the model. The same optimal configurations were then subjected to Super STOL cruise conditions to perform a tradeoff analysis between Takeoff and Cruise Performance. Supercritical airfoils modified for circulation control were also thoroughly analyzed for Takeoff and Cruise performance and may constitute a viable option for Super STOL and STOL Designs. The prediction capability produced by this research effort can be integrated with the current conceptual aircraft modeling and simulation framework. The prediction tool is applicable within the selected ranges of each variable, but methodology and formulation scheme adopted can be applied to any other design space exploration.

In this thesis, we have reported the MBE growth, design, and fabrication of the InGaAs quantum dots (QDs) laser/semiconductor optical amplifier, broadband QDs structure, coupled double cavity structure for terahertz emission on GaAs substrate. The emission wavelengths of the strain-induced S-K growth mode QDs structures are adjusted through the composition of QDs and strain-compensated capping layer. Also, the technique of growing high quality InGaAs QDs with solid source molecular beam epitaxy has been established and characterized by double crystal X-ray diffraction, transmission electron microscopy, photoluminescence, electroluminescence measurements. For 1.3£gm QDs laser samples, ridge waveguide lasers of the Fabry-Perot (FP) type are fabricated by wet-etching process. From the QDs laser L-I curve, the e2-hh2 transition at £f =1160nm have larger optical gain than e1-hh1 transition at £f =1220nm. The FP laser with 0.6£gm cavity length shows a lasing peak of 1160nm at threshold. As the cavity length increase to 2£gm, the lasing peak red shift to 1220nm (closed to ground state emission wavelength). This energy band gap transition phenomenon is obvious especially in the QDs laser with quantum well (QW) structure. When the injection current increase, two lasing peaks at £f= 1160 and 1175nm are observed sequentially. This unique lasing behavior is shown to be consistent with carriers localized in noninteracting dots. For the application of 1.3£gm light source, we optimum the growth condition for different needs in optical coherent tomography (OCT) light source, tandem solar cell, terahertz emission light source, etc. For the super luminescence diode (SLED) in OCT, we design multi-stacked asymmetric QDs structure (AMQD), QDs in the well structure (DWell), Dwell with p-doping in well structure to investigate the carrier recombination condition and bandwidth. Comparing with 5 structures in this study, the Dwell with p-doping in well structure has a maximum EL bandwidth exceed 198nm. The large bandwidth is attributed to the QW which increases the carrier capture rate and the p-doping which provide the efficient holes in valance band. This structure provides an excellent SLED light source solution to replace the existing program. For the tandem solar cell, we use the multi-stack QDs to compose broadband absorption in 1eV range. In order to avoid the degradation in the open circuit voltage, we use InGaAs QW to reduce the QDs strain. We observed the doping effect on the built in field through the photo-reflectance measurements. For the better photocurrent collection, we use p-doping in the QW to increase the built-in field intensity to obtain higher efficiency. For the terahertz emission, the QDs embedded in coupled double-cavity structures with an AlAs/GaAs intermediate distributed Bragg reflector (DBR) are grown on GaAs substrates. Two emission peaks at 1180, 1206 nm from the QDs corresponding to the coupled double-cavity resonant modes are observed in the high reflection band. The frequency differences for the two resonant coupled modes are of 5.5 terahertz, and have been successfully controlled by changing the pair numbers for the intermediate DBR. In addition, we have grown the InGa(Al)As nanostructures on InP substrate. The lattice constant difference between InGaAs and InP is relatively smaller compare with GaAs substrate, and it will be more challenge in epitaxial growth. After we investigate the strain, surface morphologies, optical properties for the nanostructures, we find the group III elements play an important role in the morphologies. Wire formation is attributed by the enhanced adatom diffusion length in the stepped surface front along [0-11] direction for the presence of Ga both in the nanostructure and buffer layer. Finally, we established QDs, Qwires database for the valuable new possibilities for designing new and original structures.