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The Global ETD Search service is a free service for researchers
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Showing 21 to 23 of 23 (0.016 seconds)Spelling suggestions: "subject:"grind"" "subject:"frind""
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Digital Microwave Control of Superconducting Qubits / Digital Mikrovågskontroll av Supraledande KvantbitarDi Carlo, Giuseppe Ruggero January 2022 (has links)
We manipulate two superconducting qubits using digital microwave electronics. Starting fromtheir characterization, we develop a real-time reset scheme and implement the iSwap gate. Thequbits’ parameters are obtained using standard single-qubit characterization techniques, such asRabi and Ramsey oscillations and frequency sweep of the resonators. We also characterized theexperimental setup, including finding the working point of a Josephson Parametric Amplifierand the coupler between the two qubits. We solve the linear differential equations that modelthe resonator, in order to design a high-fidelity, single-shot qubit-measurement pulse shape,which actively empties the cavity. Using this pulse, we achieve a readout assignment fidelity of99.9%. The readout is formed in real-time using template matching. In addition, we implementa conditional reset of the qubit’s state in 1.4 μs, which resets the excited state population from5.4% to 0.5%. We simulate the cavity using QuTip to further optimize the readout pulse.Furthermore, we characterize the third energy level of the qubit to implement a qutrit readoutand observe a second excited state population of 0.3%, in accordance with theory. Finally,we implement the iSwap gate that, together with single-qubit gates, constitute a set of universalquantum gates, where we swap the 95.4% of the quantum state between the qubits in 690 ns. Allexperiments, including the pulse events and synchronization of the readout and feedback, wereperformed using a digital microwave platform based on a radio-frequency-on-a-chip system,and implemented using a Python interface. / Vi manipulerar två supraledande kvantbitar med digital mikrovågselektronik. Vi utgår frånderas karakterisering och utvecklar en realtidsåterställningsschema och implementerar iSwap-grinden. Kvantbitarnas parametrar erhålls med standardtekniker för karakterisering av enskildakvantbitar, såsom Rabi- och Ramsey-svängningar och frekvenssvep av resonatorerna. Vikaraketeriserar även den experimentella uppställningen, där vi finner arbetspunkten för enJosephson-parametrisk förstärkare, samt kopplaren mellan de två kvantbitarna. Vi löser delinjära differentialekvationerna som modellerar resonatorn, i syfte att designa en pulsformför en enkelmätning av en kvantbit med hög tillförlitlighet som aktivt tömmer kaviteten.Med denna puls uppnår vi en avläsningstillförlitlighet på 99,9 %. Avläsningspulsen bildas irealtid med hjälp av mallmatchning. Därtill implementerar vi en villkorlig återställning avkvantbitens tillstånd på 1,4 μs, vilket återställer den exciterade tillståndspopulationen från 5,4 %till 0,5 %. Vi simulerar kaviteten med QuTip för att ytterligare optimera avläsningspulsen.Dessutom karakteriserar vi den tredje energinivån på kvantbiten för att implementera enså-kallad qutrit-avläsning och observerar en andraexciterad tillståndspopulation på 0,3 %,i enlighet med teorin. Slutligen implementerar vi iSwap-grinden som, tillsammans medgrindarna för enskilda kvantbitar, utgör en uppsättning universella kvantgrindar, är vi byter95,4 % av kvanttillståndet mellan våra kvantbitarna på 0,6 μs. Alla experiment, såsompulshändelserna och synkroniseringen av avläsningspulsen och återkopplingspulsen, utfördesmed hjälp av en digital mikrovågsplattform, baserad på ett radiofrekvens-på-ett-chip-system,och implementerades med ett Python-gränssnitt.
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Glide Quality in Cross-Country Skiing : The Topographical and Frictional Impact of the Stone GrindJohansson, Martin January 2022 (has links)
The Swedish Winter Olympic team is one of the strongest Olympic teams in theworld, and the majority of the team’s success comes from ski-related sports. So howcan the Swedish team remain, and maybe even accelerate, its competitive advantage? The answer is science. In order to narrow down the broad field that is equipment development, this thesishad the purpose to examine the stone grind’s impact on friction between the ski andthe snow. To achieve this purpose, the project was designed to answer these threequestions: • How does the ski base impact the friction between the ski and the snow? • How do the stone grind’s parameters impact the ski base? • How do the stone grind’s parameters impact the friction between the ski andthe snow? To answer these questions, a total of three pilot tests were done before the finalfull-scale experiment. The method to strategically test the parameters of the stonegrind was to use a full two-level factorial design, with a total of three stone grindparameters being investigated. Those parameters were: Cutting Depth, Line Density,and Wheel Pressure. The skis were tested in Arctic Fall’s indoor facilities where theskis were tested with a winch set-up to get the skis up to a desired speed, and thedata collected from the test were speed data from each of the skis. This speed datawould then be used to calculate the coefficient of friction acting between the ski andthe snow. To understand the stone grinds parameters on the ski base, the ski basesurfaces were measured after the skis were grounded, to build a regression modelconsisting of stone grind parameters as independent variables, and surface parametersbeing the dependent variables. A model was created suggesting that in the conditions the tests were executed, thesurface parameters Sa should be minimized and Sm should be maximized to achievea minimized coefficient of friction. A more generalisable model to impact the surfaceparameters Sa and Sm was also generated. It suggests that to impact Sa and Sm, itis the stone grind parameter Cutting Depth and Line Density that should be adjustedto achieve a desirable ski base structure.
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Development of high-performance algorithms for a new generation of versatile molecular descriptors. The Pentacle softwareDurán Alcaide, Ángel 04 March 2010 (has links)
The work of this thesis was focused on the development of high-performance algorithms for a new generation of molecular descriptors, with many advantages with respect to its predecessors, suitable for diverse applications in the field of drug design, as well as its implementation in commercial grade scientific software (Pentacle). As a first step, we developed a new algorithm (AMANDA) for discretizing molecular interaction fields which allows extracting from them the most interesting regions in an efficient way. This algorithm was incorporated into a new generation of alignmentindependent molecular descriptors, named GRIND-2. The computing speed and efficiency of the new algorithm allow the application of these descriptors in virtual screening. In addition, we developed a new alignment-independent encoding algorithm (CLACC) producing quantitative structure-activity relationship models which have better predictive ability and are easier to interpret than those obtained with other methods. / El trabajo que se presenta en esta tesis se ha centrado en el desarrollo de algoritmos de altas prestaciones para la obtención de una nueva generación de descriptores moleculares, con numerosas ventajas con respecto a sus predecesores, adecuados para diversas aplicaciones en el área del diseño de fármacos, y en su implementación en un programa científico de calidad comercial (Pentacle). Inicialmente se desarrolló un nuevo algoritmo de discretización de campos de interacción molecular (AMANDA) que permite extraer eficientemente las regiones de máximo interés. Este algoritmo fue incorporado en una nueva generación de descriptores moleculares independientes del alineamiento, denominados GRIND-2. La rapidez y eficiencia del nuevo algoritmo permitieron aplicar estos descriptores en cribados virtuales. Por último, se puso a punto un nuevo algoritmo de codificación independiente de alineamiento (CLACC) que permite obtener modelos cuantitativos de relación estructura-actividad con mejor capacidad predictiva y mucho más fáciles de interpretar que los obtenidos con otros métodos.
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