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Convolutional Neural Network (CNN) has undergone tremendous advancements in recent years, but visual reasoning tasks are still a huge undertaking, particularly in few-shot learning cases. Little is known, especially in solving the Same-Different (SD) task, which is a type of visual reasoning task that requires seeking pattern repetitions in a single image. In this thesis, we propose a patch-as-filter method focusing on solving the SD tasks with few-shot learning. Firstly, a patch in an individual image is detected. Then, transformations are learned to create sample-specific convolutional filters. After applying these filters on the original input images, we, lastly, acquire feature maps indicating the duplicate segments. We show experimentally that our approach achieves the state-of-the-art few-shot performance on the Synthetic Visual Reasoning Test (SVRT) SD tasks by accuracy going up above 30% on average, with only ten training samples. Besides that, to further evaluate the effectiveness of our approach, SVRT-like tasks are generated with more difficult visual reasoning concepts. The results suggest that the average accuracy is increased by approximately 10% compared to several popular few-shot algorithms. The method we suggest here has shed new light upon new CNN approaches in solving the SD tasks with few-shot learning.

In vivo or whole-cell solid-state NMR is an emerging field which faces tremendous challenges. In most cases, cell biochemistry does not allow the labelling of specific molecules and an in vivo study is thus hindered by the inherent difficulty of identifying, among a formidable number of resonances, those arising from a given molecule. In this work we examined the possibility of studying, by solid-state NMR, the model organism Chlamydomonas reinhardtii fully and non-specifically 13C labelled. The extension of NMR-based dynamic filtering from one-dimensional to two-dimensional experiments enabled an enhanced selectivity which facilitated the assignment of cell constituents. The number of resonances detected with these robust and broadly applicable experiments appears to be surprisingly sparse. Various constituents, notably galactolipids abundant in organelle membranes, carbohydrates from the cell wall, and starch from storage grains could be unambiguously assigned. Moreover, the dominant crystal form of starch could be determined in situ. This work illustrates the feasibility and caveats of using solid-state NMR to study intact non-specifically 13C labelled micro-organisms.

In this paper, a new type of trajectory, based on an exponential jerk, is presented along with filters for their online generation. The goal is to generalize constant jerk trajectories, widely used in industrial applications, in order to reduce vibrations of motion systems. As a matter of fact, constant jerk trajectories do not assure a complete vibration suppression when the damping of the resonant modes is not negligible. The values of the parameters (decay rate and duration) of the jerk impulses that allow residual vibration cancellation are derived in an analytical way as a function of the dynamic characteristics of the plant. Comparisons with the well-known input shaping techniques and with system-inversion-based filters show the advantages of the proposed method in terms of robustness with respect to modeling errors, smoothness of the resulting trajectory, and time duration of the motion under velocity and acceleration constraints.

This work proposes an extended study on real-time trajectory planners for mechatronic systems. Designed planners are based on the so-called path-velocity decomposition paradigm, i.e. trajectories are obtained by first designing the desired geometric path and, then, by associating a time-law to the movement along it. In particular, the first proposed real-time trajectory planner (named Trajectory Scaling System) acts in the configuration space and is able to scale down the longitudinal velocity in order to fulfill a given set of constraints associated to the mechatronic system. More precisely, it manages, in real-time, kinematic constraints on joint velocities, accelerations, and jerks as well as dynamic constraints on generalized joint forces and their derivatives. The same planning scheme has been successively applied to trajectories defined in the operational space. In this case, the planner handles in real-time kinematic bounds on joint velocities, accelerations and jerks. The scaling system has been validated through experimental tests performed on an actual 6 degrees of freedom manipulator by executing a set of different Cartesian paths passing close to singular points. The last considered planning problem concerns the real-time end-effector orientation modification made in order to maintain an exact tracking of the planned time-law. Even in this case, the planning scheme has been validated through experimental tests executed on an anthropomorphic manipulator by performing Cartesian paths passing close to, or even crossing, kinematic singularities. La tesi presenta uno studio estensivo sulla pianificazione di traiettorie in tempo reale per sistemi meccatronici. I pianificatori presentati sono basati sul paradigma di pianificazione denominato decomposizione velocità-percorso: la traiettoria è ottenuta come il risultato della composizione di un percorso geometrico e di una legge oraria che descrive la velocità del punto pianificato lungo il percorso. Il primo pianificatore in tempo reale presentato (denominato Trajectory Scaler System) descrive traiettorie nello spazio dei giunti ed è in grado di diminuire la velocità longitudinale per soddisfare i vincoli presenti nei sistemi meccatronici. Il pianificatore considera sia i vincoli cinematici di velocità, accelerazione e jerk di giunto sia i vincoli dinamici di forza generalizzata e di derivata di forza generalizzata agente sui giunti. Lo stesso schema di pianificazione è stato successivamente applicato per traiettorie definite nello spazio operativo. In questo caso sono stati considerati e gestiti in tempo reale i vincoli cinematici di velocità, accelerazione e jerk di giunto. Il sistema è stato validato attraverso dei test sperimentali eseguiti su un robot antropomorfo a 6 gradi di libertà eseguendo percorsi passanti nei pressi di singolarità cinematiche. Infine è stato studiato il problema della modifica in tempo reale dell'orientazione di una traiettoria per un robot antropomorfo mantenendo un esatto inseguimento della legge oraria pianificata. Il sistema è stato anch'esso validato mediante traiettorie eseguite su un robot antropomorfo compiendo traiettorie che transitano per punti di singolarità.

Ankara : The Materials Science and Nanotechnology Program of the Graduate School of Engineering and Science of Bilkent University, 2014. Thesis (Master's) -- Bilkent University, 2014. Includes bibliographical references leaves 54-57. In this study, we design and produce grating coupled surface plasmon surfaces which are switched by electrochemistry. Grating structures are fabricated using digital versatile discs (DVDs) which are commercially available. According to atomic force microscopy (AFM) results, we categorize the different grating structures in two groups, namely shallow and deep gratings. Plasmonic properties of the surfaces are investigated using numerical simulations. Gold and silver are used as plasmon supporting metallic layers on gratings. Refractive index sensitivity of the plasmon resonances are studied using deionized water, air and glycerol solutions as the dielectric media and results are compared with simulations. Experimental results are coherent with the simulations in terms of reflection spectra. Electrochemical switching of plasmonic properties may have applications in tunable and switchable filters, as well as enhanced colorimetric sensing. We deposit ultrathin films of copper on plasmonic surfaces and investigate reversible changes in the plasmonic properties. Copper sulfate is selected as the electrolyte. Cyclic voltammetry is performed on plasmonic surfaces while monitoring optical reflectance. Copper is observed to deposit in the form of nanoislands on silver and gold films rather than uniform thin films. The effect of copper deposition on the plasmonic properties of the grating structure is simulated by Lumerical software and is seen to be two fold. For small effective thickness of copper nanoislands, the plasmon resonance condition shifts, whereas for thicker copper deposition plasmonic resonances are eliminated. Finally, copper's oxidation and reduction reactions are controlled by changing applied voltage thus shifting the resonance wavelength. Resonances are switched reversibly multiple times not only for different molarities but also for different grating sructures and plasmon supporting metallic layers . In summary, we demonstrate that plasmonic properties of nanostructured metallic surfaces can be controlled by electrochemistry. Switchable resonance surfaces can be used as dynamic filters or may enhanced contrast in plasmon resonance imaging applications. Karayalçın, Nihat Serkan M.S.

Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-12-05T16:28:50Z No. of bitstreams: 1 SUZANA ARAÚJO BARBOSA – DISSERTAÇÃO (PPGFísica) 2013.pdf: 4287089 bytes, checksum: ea83819f66b68fa4cae01975c1122a18 (MD5) Made available in DSpace on 2018-12-05T16:28:50Z (GMT). No. of bitstreams: 1 SUZANA ARAÚJO BARBOSA – DISSERTAÇÃO (PPGFísica) 2013.pdf: 4287089 bytes, checksum: ea83819f66b68fa4cae01975c1122a18 (MD5) Previous issue date: 2013 Capes Sabe-se que para garantir um melhor resultado no tratamento dos pacientes em Radioterapia é conveniente uma constância de parâmetros físicos como também a verifi cação do sistema de planejamento trabalhado. O trabalho que segue apresenta um estudo das propriedades físicas dos filtros dinâmicos do acelerador linear 6eX, da Varian Medical Systems, por meio de veri cações experimentais, comparando-as com cálculos desenvolvidos pelo sistema de planejamento Eclipse, sob as mesmas condições. Foram determinados os fatores fi ltro para campos simétricos e assimétricos para o eixo central e fora dele, veri cando a influência dos colimadores X e Y em diferentes aberturas; veri ficou-se também a dependência do fator filtro com a profundidade, com o aumento dos campos e com o aumento do ângulo empregado nos fi ltros, além dos per s dos campos para profundidade específi cas. A interpretação dos resultados dos fatores fi ltro, possibilita os cálculos do planejamento do tratamento em Radioterapia para uma eventual falta ou conferência do sistema de planejamento. It is known that to ensure a better outcome in the treatment of patients in Radiotherapy, there should be a constancy of the physical parameters as well as a verification of the worked planning system. The following work presents a study of the physical properties of the dynamic lters of the linear accelerator 6ex, from Varian Medical Systems, using experimental veri cation by comparing them with calculations made by the planning system Eclipse under the same conditions. The lter factors were determined for symmetrical and asymmetrical elds to the central axis and off of it, by checking the influence of collimators X and Y in di erent openings, there is also the dependence of the lter factor with the depth, with the increase of the elds and angles used in the lters, and the eld pro les for specifi c depths. The interpretation of the results of the lter factors, enables calculations in radiotherapy treatment planning, for a possible lack of planning system.

In this work, several procedures for the fault detection and isolation (FDI) on general aviation aircraft sensors are presented. In order to provide a comprehensive wide-spectrum treatment, both linear and nonlinear, model-based and data-driven methodologies are considered. The main contributions of the paper are related to the development of both FDI polynomial method (PM) and FDI scheme based on the nonLinear geometric approach (NLGA). As to the PM, the obtained results highlight a good trade-off between solution complexity and resulting performances. Moreover, the proposed PM is especially useful when robust solutions are required for minimising the effects of modelling errors and noise, while maximising fault sensitivity. As to the NLGA, the proposed work is the first development and robust application of the NLGA to an aircraft model in flight conditions characterised by tight-coupled longitudinal and lateral dynamics. In order to verify the robustness of the residual generators related to the previous FDI techniques, the simulation results adopt a typical aircraft reference trajectory embedding several steady-state flight conditions, such as straight flight phases and coordinated turns. Moreover, the simulations are performed in the presence of both measurement and modelling errors. Finally, extensive simulations are used for assessing the overall capabilities of the developed FDI schemes and a comparison with neural networks (NN) and unknown input Kalman filter (UIKF) diagnosis methods is performed.

International audience; We discuss interval techniques for speeding up the exact evaluation of geometric predicates and describe a C++ implementation of interval arithmetic that is strongly influenced by the rounding modes of the widely used IEEE 754 standard. Using this approach we engineer an efficient floating point filter for the computation of geometric predicates. We validate our approach experimentally, comparing it with other static, dynamic and semi-static filters.