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Stega, Alessandro Pio. "Sviluppo di un'applicazione per lo scheduling di processi periodici con vincoli temporali." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016.
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Ranaldo, Pierfrancesco. "Modelli ILP per la determinazione delle prestazioni conseguibili con il protocollo "Priority Inheritance" in applicazioni multitasking hard real-time." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13059/.
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Regole ed esempi pratici sulla costruzione di Modelli di Programmazione Lineare Intera per la rappresentazione di task periodici di Applicazioni Real-Time e delle loro interazioni bloccanti; utili per la determinazione del "massimo tempo di blocco" che i processi possono subire, nell'ipotesi: che siano schedulati con strategia "Rate Monotonic Priority Order"; che la politica di gestione degli accessi alle risorse condivise sia quella definita dal protocollo "Priority Inheritance".
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Jain, Nikhil. "Process Development for ICP Patterning of Through-wafer Periodic Micro-Pores in Silicon Wafers." University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1282328382.
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Nilchan, Sujinda. "The optimisation of periodic adsorption processes." Thesis, Imperial College London, 1997. http://hdl.handle.net/10044/1/64999.
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Periodic adsorption processes have been gaining increasing commercial acceptance as energy efficient alternatives to other separation processes. Such processes are distributed in nature, with properties exhibiting spatial as well as temporal variations. Therefore, they can be mathematically represented by systems of partial differential and algebraic equations (PDAEs).The periodic nature of periodic adsorption processes arises from an externally imposed cyclic variation of the flowrates and intensive properties (e.g. pressure, temperature or composition) of the process feed streams, and of the flowrates of the product streams. This variation leads the system to a "cyclic steady state" (CSS) at which the conditions in each bed at the start and end of each cycle are identical. The traditional approach to cyclic steady state determination has been to carry out a dynamic simulation of the system, starting from a given initial condition, over a large number of cycles. In this work, a novel method is proposed to directly determine a cyclic steady state of periodic adsorption processes by replacing the initial condition specification by a periodicity condition demanding that the system states at the end of each cycle be identical to those at its start. Additional constraints are introduced to characterise the interactions between multiple beds in the process. Detailed dynamic models taking account of the spatial variation of properties within the adsorption bed(s) are used. The resulting systems of partial differential and algebraic equations, and the corresponding boundary conditions, are reduced to sets of algebraic constraints by discretisation with respect to both spatial and temporal dimensions. The performance of periodic adsorption processes is intrinsically affected by various design and operating parameters. The appropriate selection of the values of these parameters may significantly enhances the entire profit of the processes. However, the number of interacting decisions and constraints is such that obtaining an optimal solution by carrying out several dynamic simulations is laborious, if not altogether impossible. A new approach to the optimisation of periodic adsorption processes using mathematical programming is presented. It is demonstrated that the optimal operating and/or design decisions can be determined by solving a single optimisation problem with constraints representing a single bed over a single cycle of operation, irrespective of the number of adsorption beds in the process. Examples of periodic adsorption processes involving different number of adsorption beds and operating cycles are presented to illustrate the approach.
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Noorzadeh, Saman. "Extraction de l'ECG du foetus et de ses caractéristiques grâce à la multi-modalité." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAT135/document.
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La surveillance de la santé foetale permet aux cliniciens d’évaluer le bien-être du foetus,de faire une détection précoce des anomalies cardiaques foetales et de fournir les traitementsappropriés. Les développements technologies actuels visent à permettre la mesurede l’électrocardiogramme (ECG) foetal de façon non-invasive afin d’extraire non seulementle rythme cardiaque mais également la forme d’onde du signal. Cet objectif est rendudifficile par le faible rapport signal sur bruit des signaux mesurés sur l’abdomen maternel.Cette mesure est donc toujours un challenge auquel se confrontent beaucoup d’études quiproposent des solutions de traitement de signal basées sur la seule modalité ECG.Le but de cette thèse est d’utiliser la modélisation des processus Gaussiens pour améliorerl’extraction des signaux cardiaques foetaux, dans une base multi-modale. L’ECG est utiliséconjointement avec le signal Phonocardiogramme (PCG) qui peut apporter une informationcomplémentaire à l’ECG. Une méthode générale pour la modélisation des signauxquasi-périodiques est présentée avec l’application au débruitage de l’ECG et à l’extractionde l’ECG du foetus. Différents aspects de la multi-modalité (synchronisation, · · · ) proposéesont étudiées afin de détecter avec plus de robustesse les battements cardiaques foetaux.La méthode considère l’application sur les signaux ECG et PCG à travers deux aspects:l’aspect du traitement du signal et l’expérimental. La modélisation des processus Gaussien,avec le signal PCG pris comme la référence, est utilisée pour extraire des modèles flexibleset des estimations non linéaires de l’information. La méthode cherche également à faciliterla mise en oeuvre pratique en utilisant un codage 1-bit des signaux de référence.Le modèle proposé est validé sur des signaux synthétiques et également sur des donnéespréliminaires réelles qui ont été enregistrées afin d’amorcer la constitution d’une base dedonnées multi-modale synchronisée. Les premiers résultats montrent que la méthode permettraà terme aux cliniciens d’étudier les battements cardiaques ainsi que la morphologiede l’ECG. Ce dernier aspect était jusqu’à présent limité à l’analyse d’enregistrements ECGinvasifs prélevés pendant l’accouchement par le biais d’électrodes posées sur le scalp dufoetusFetal health must be carefully monitored during pregnancy to detect early fetal cardiac diseases, and provide appropriate treatment. Technological development allows a monitoring during pregnancy using the non-invasive fetal electrocardiogram (ECG). Noninvasive fetal ECG is a method not only to detect fetal heart rate, but also to analyze the morphology of fetal ECG, which is now limited to analysis of the invasive ECG during delivery. However, the noninvasive fetal ECG recorded from the mother's abdomen is contaminated with several noise sources among which the maternal ECG is the most prominent.In the present study, the problem of noninvasive fetal ECG extraction is tackled using multi-modality. Beside ECG signal, this approach benefits from the Phonocardiogram (PCG) signal as another signal modality, which can provide complementary information about the fetal ECG.A general method for quasi-periodic signal analysis and modeling is first described and its application to ECG denoising and fetal ECG extraction is explained. Considering the difficulties caused by the synchronization of the two modalities, the event detection in the quasi-periodic signals is also studied which can be specified to the detection of the R-peaks in the ECG signal.The method considers both clinical and signal processing aspects of the application on ECG and PCG signals. These signals are introduced and their characteristics are explained. Then, using PCG signal as the reference, the Gaussian process modeling is employed to provide the possibility of flexible models as nonlinear estimations. The method also tries to facilitate the practical implementation of the device by using the less possible number of channels and also by using only 1-bit reference signal.The method is tested on synthetic data and also on real data that is recorded to provide a synchronous multi-modal data set.Since a standard agreement for the acquisition of these modalities is not yet taken into much consideration, the factors which influence the signals in recording procedure are introduced and their difficulties and effects are investigated.The results show that the multi-modal approach is efficient in the detection of R-peaks and so in the extraction of fetal heart rate, and it also provides the results about the morphology of fetal ECG
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Reis, Ricardo Luis dos. "Modelos autorregressivos periódicos para previsão e geração de séries de vazões médias mensais." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-13052013-111226/.
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Este trabalho aborda o problema de modelagem de séries de vazões médias mensais visando previsão e geração de séries sintéticas. Destaca-se que a importância da previsão de valores futuros das séries mensais de vazões assim como a geração de séries sintéticas são fundamentais para o planejamento da operação de sistemas hidroelétricos brasileiros. Estas séries possuem um comportamento periódico na média, na variância e na função de autocorrelação e, portanto, considera-se para a série padronizada os modelos autorregressivos periódicos PAR(pm). Em relação a previsão clássica, a análise do erro de previsão e feita em função do horizonte de previsão. Neste estudo, os erros de previsão são calculados, na escala original da série de vazão, em função dos parâmetros dos modelos ajustados e avaliados para horizontes de previsão h variando de 1 a 12 meses. Estes erros são comparados com as estimativas das variâncias das vazões para o mês que está sendo previsto. Em relação à previsão bayesiana, adota-se os modelos Normal, Log-Normal e t-Student nos processos de estimação e, após, é realizado um estudo da perfomance destes modelos usando o erro quadrático médio, erro absoluto médio e erro percentual absoluto médio. Em relação à geração de séries sintéticas de vazões, um modelo multivariado Log-Normal com três parâmetros e um modelo Log-Normal generalizado foram desenvolvidos. As séries geradas são comparadas com as séries históricas reais utilizando o critério de Kullback-Leibler. Como resultado, tem-se uma avaliação da capacidade de previsão, em meses, dos modelos ajustados para cada mês e a escolha do modelo Log-Normal nos procedimentos de análise bayesiana. Além disso, o modelo utilizado para a geração de séries sintéticas de vazões mensais forneceu evidências que o apontam como uma alternativa ao modelo amplamente adotado no setor elétrico brasileiro para geração de séries de vazõesThis work addresses the problem of forecasting and generation series monthly average streamflows. It is noteworthy that the importance of forecasting future values of the series of monthly streamflows as well as the generation of synthetic series are fundamental for planning the operation of Brazilian hydroelectric systems. These series have a periodic behavior on average, variance and autocorrelation function and therefore it is considered for standard series periodic autoregressive models PAR(pm). At the forecast classical analysis of the prediction error is made in function of the prediction horizon. In this study, the forecasting errors are calculated in the original scale of the series of streamflow, depending on the model parameters adjusted and evaluated for forecasting horizons h ranging from 1 to 12 months. These errors are compared with estimates of the variances of the streamflows for the month is provided. Regarding the bayesian prediction, we adopt the models Normal, Log-Normal and t-Student in estimation procedures and, then, is a study of the performance of these models using the mean square error, mean absolute error and mean absolute percentage error. In relation to generation, a Log-Normal multivariate model with three parameters and a Log-Normal generalized model were developed and analyzed using the Kullback-Leibler criterion. As a result there has been an assessment of the predictive power, in months, the adjusted models for each month, the choice of the Log-Normal model in the procedures for bayesian analysis and the model used to generate synthetic series of monthly streamflows provided evidence that point as an alternative model adopted in the Brazilian electric sector
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Lauwerier, Rémi. "Automation of periodic replenishment process for fashionable product." Thesis, KTH, Industriell produktion, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-201654.
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The thesis depicted in this report was the subject of my internship at Dior Haute Couture in Paris. I was a member of the supply chain team and I was working on the women shoes product. The aim was to develop the automation of the replenishment of the stores in the world. As a planner for Europe and the United States, I was in strong interaction with the buyers who were following specific stores and who have strong knowledge about the product. The product required a well understanding of the trend of the market and a significant reactivity to cope with the hazards of the of the fashion industry in the luxury world. The purpose to reach was double: first the automation model should reduce time of the planner job to replenish the stores and secondly the application should give more clarity on the goals decided on the market. Along the development, I have always kept in mind the guarantee of the replenishment quality and the simplification of the planner job.The first chapter of this thesis will refer to the start of my investigation to apply a relevant model to my study case: the definition of the project and a state of art of the different methods to supply a store found in the literature. In the second chapter I will explain the choices I did for the automation of replenishment system. The project was very specific to the company and depends a lot on the intrinsic characteristics of the product. As they were luxury products, the goal was to deliver appropriate grid sizes of women shoes to stores to make the best sales as possible with the less level of stock. The project takes also into account the quality issues to face and the approximations of the production planning.By building this model, it appears that the criteria taken on could be used for wider applications. As a consequence, in the last chapter, I will deal with a new way to calculate stock out rate indicators. The global aim was again to clarify the planner job and to enable him to warn the buyer about critical stocks in the stores.
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Vetukuri, Sree Rama Raju. "Advanced Optimization Strategies for Periodic Adsorption Processes." Research Showcase @ CMU, 2011. http://repository.cmu.edu/dissertations/30.
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Periodic Adsorption Processes (PAPs) have gained increasing commercial importance asan energy-efficient separation technique over the past two decades. Based on fluid-solidinteractions, these systems never reach steady state. Instead they operate at cyclic steadystate, where the bed conditions at the beginning of the cycle match with those at the endof the cycle. Nevertheless, optimization of these processes remains particularly challenging,because cyclic operation leads to dense Jacobians, whose computation dominatesthe overall cost of the optimization strategy. In order to efficiently handle these Jacobiansduring optimization and reduce the computation time, this work presents newcomposite step trust-region algorithms based on sequential quadratic programming andinterior point methods for the solution of minimization problems with both nonlinearequality and inequality constraints. Instead of forming and factoring the dense constraintJacobian, these algorithms approximate the Jacobian of equality constraints with a specializedquasi-Newton method. Hence, they are well suited to solve optimization problemsrelated to PAPs. In addition to allowing inexactness of the Jacobian and its null-spacerepresentation, the algorithm also provides exact second order information in the formof Hessian-vector products to improve the convergence rate. The resulting approachalso combines automatic differentiation and more sophisticated integration algorithms toevaluate the direct sensitivity and adjoint sensitivity equations. Numerical performance results on small scale PAP problems and CUTEr problems show significant reduction incomputation time.
Furthermore, we propose a systematic methodology to design PSA cycles using asuperstructure based approach. The superstructure is rich enough to predict a numberof different PSA operating steps, and their optimal sequence is obtained by solving anoptimal control problem. PSA is a potential technology for pre-combustion CO2 capturebecause of low operating costs and high performance. We utilize the superstructureapproach to synthesize PSA cycles for this purpose which can separate both H2 andCO2 at high purity and operate with a low power consumption of 86 kWh/tonne of CO2captured.
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Mohamed, Alkadour Abdulkahar [Verfasser]. "Periodic ARMA, Ornstein-Uhlenbeck and CARMA processes as periodic time series / Abdulkahar Mohamed Alkadour." Ulm : Universität Ulm, 2018. http://d-nb.info/1166756823/34.
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Akgun, Burcin. "Identification Of Periodic Autoregressive Moving Average Models." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1083682/index.pdf.
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In this thesis, identification of periodically varying orders of univariate
Periodic Autoregressive Moving-Average (PARMA) processes is mainly studied.
The identification of the varying orders of PARMA process is carried
out by generalizing the well-known Box-Jenkins techniques to a seasonwise
manner. The identification of pure periodic moving-average (PMA) and pure
periodic autoregressive (PAR) models are considered only. For PARMA model
identification, the Periodic Autocorrelation Function (PeACF) and Periodic Partial
Autocorrelation Function (PePACF), which play the same role as their ARMA
counterparts, are employed.
For parameter estimation, which is considered only to refine model
identification, the conditional least squares estimation (LSE) method is used
which is applicable to PAR models. Estimation becomes very complicated,
difficult and may give unsatisfactory results when a moving-average (MA)
component exists in the model. On account of overcoming this difficulty,
seasons following PMA processes are tried to be modeled as PAR processes
with reasonable orders in order to employ LSE. Diagnostic checking, through
residuals of the fitted model, is also performed stating its reasons and methods.
The last part of the study demonstrates application of identification
techniques through analysis of two seasonal hydrologic time series, which
consist of average monthly streamflows. For this purpose, computer programs
were developed specially for PARMA model identification.
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Ghassemi, Nooshin Haji. "Analytic Long Term Forecasting with Periodic Gaussian Processes." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5458.
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In many application domains such as weather forecasting, robotics and machine learning we need to model, predict and analyze the evolution of periodic systems. For instance, time series applications that follow periodic patterns appear in climatology where the CO2 emissions and temperature changes follow periodic or quasi-periodic patterns. Another example can be in robotics where the joint angle of a rotating robotic arm follows a periodic pattern. It is often very important to make long term prediction of the evolution of such systems. For modeling and prediction purposes, Gaussian processes are powerful methods, which can be adjusted based on the properties of the problem at hand. Gaussian processes belong to the class of probabilistic kernel methods, where the kernels encode the characteristics of the problems into the models. In case of the systems with periodic evolution, taking the periodicity into account can simplifies the problem considerably. The Gaussian process models can account for the periodicity by using a periodic kernel. Long term predictions need to deal with uncertain points, which can be expressed by a distribution rather than a deterministic point. Unlike the deterministic points, prediction at uncertain points is analytically intractable for the Gaussian processes. However, there are approximation methods that allow for dealing with uncertainty in an analytic closed form, such as moment matching. However, only some particular kernels allow for analytic moment matching. The standard periodic kernel does not allow for analytic moment matching when performing long term predictions. This work presents an analytic approximation method for long term forecasting in periodic systems. We present a different parametrization of the standard periodic kernel, which allows us to approximate moment matching in an analytic closed form. We evaluate our approximate method on different periodic systems. The results indicate that the proposed method is valuable for the long term forecasting of periodic processes.
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Powell, Keddon A. "Improving continuous crystallisation using process analytical technologies : design of a novel periodic flow process." Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/23982.
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In this thesis novel configurations and operating strategies in the mixed suspension mixed product removal (MSMPR) crystalliser are investigated, aided by integrated process analytical technologies (PAT) and crystallisation informatics system (CryPRINS) tools. The MSMPR is an idealised crystalliser model that assumes: steady-state operation; well mixed suspension with no product classification, such that all volume elements contain a mixture of particles (small and large) and crystal size distribution (CSD) that is independent of location in the crystalliser and is identical of the product withdrawn; and uniform supersaturation thought, leading to constant nucleation and growth rates. Single-stage MSMPR designs with continuous recycle/recirculation and modified heat exchanger were investigated and found to minimise fouling, encrustation and transfer line blockages. In particular, a modified MSMPR with baffled heat exchanger was found to significantly reduce the temperature between incoming feed hot feed solution and the cooled crystalliser, leading to a significant reduction in fouling, encrustation and blockages. In addition, the concept of the periodic mixed suspension mixed product removal (PMSMPR) crystallisation process is demonstrated for the first time viz single- and multi-stage cascaded operations. This method of operation involves the periodic transfer of slurry (addition and withdrawal) at high flow rates from either a single stirred vessel or between a number of stirred vessels arranged in series. The PMSMPR is therefore characterised by periodic withdrawals of product slurry. Similar to the MSMPR, the product withdrawn from a PMSMPR has exactly the same composition as the vessel at the time of removal. The rapid withdrawal of slurry at high flow rates in PMSMPR operation leads to the prevention of particle sedimentation and blockage of transfer lines. The transfer of slurry (to/from) the PMSMPR is followed by a holding (or pause) period when no addition or withdrawal of slurry takes place. The holding period extends the mean residence time of the PMSMPR relative to a typical MSMPR, thereby increasing the yield and productivity of crystallisation as more time is allowed for consumption of available supersaturation viz crystal growth and nucleation. A state of controlled operation (SCO) in the periodic flow process, defined as a state of the system that maintains itself despite regular, but controlled disruptions was characterised using the PAT tools and CryPRINS within an intelligent decision support (IDS) framework. The crystallisation of paracetamol (PCM) from isopropyl alcohol (IPA) using different configurations of a single-stage continuous MSMPR crystalliser that incorporated continuous recycle and recirculation loop, and a novel design with baffled heat exchanger was investigated. Crystallisations of PCM-IPA carried out in the MSMPR without heat exchanger suffered from severe fouling, encrustation and blockage problems due to the high level of supersaturation (S = 1.39) in the crystalliser, which was required for the initial burst of nucleation to generate enough particles for later growth, as well as the large temperature difference between the incoming feed (45 oC) and the crystalliser (10 oC). Using the modified MSMPR design with baffled heat exchanger, the challenges of fouling, encrustation and blockage were significantly reduced due to the rapid lowering of the feed stream temperature prior to entering the crystalliser. In addition, the closed loop system led to conservation of material, which is a great benefit since large amounts of materials would otherwise be required if the MSMPR was operated with continuous product removal. This design is great for research purposes, in particular, to investigate process design and optimisation. Continuous crystallisation of PCM in the presence of hydroxyl propyl methyl cellulose (HPMC) additive was investigated in the modified MSMPR design with heat exchanger. HPMC was found to improve the crystallisation performance, leading to complete avoidance of fouling, encrustation and blockages at a concentration of 0.05 wt%. However, the yield of crystallisation was significantly reduced (28.0 %) compared to a control experiment (98.8 %, biased due to fouling/encrustation) performed without additive addition. Regardless, the productivity of crystallisation was more than four times that achieved in batch linear cooling (LC) (0.62 0.86 g/L-min) and batch automated dynamic nucleation control (ADNC) (0.24 0.25 g/L-min) runs. Aspects of the periodic flow crystallisation of single- and multi-component (co-crystals) molecular systems have also been examined to demonstrate the concept of state of controlled operation . The single component systems studied were PCM and glycine (GLY), each representative of compounds with slow and fast growth kinetics, respectively. The co-crystal systems investigated were urea-barbituric acid (UBA) and p Toluenesulfonamide-Triphenylphosphine oxide (p-TSA-TPPO). UBA is a polymorphic co-crystal system with three known forms (I, II and III). Form I UBA was successfully isolated in a three-stage periodic flow PMSMPR crystalliser. This study demonstrates the capability of periodic flow crystallisation for isolation of a desired polymorph from a mixture. p-TSA-TPPO exists in two known stoichiometric co-crystal forms, 1:1 and 3:2 mole ratio p-TSA-TPPO, respectively. The two crystalline forms exhibit solution mediated transformation, which proves to be a difficulty for separation. For this study, the implementation of temperature cycles in batch and flow control in semi-batch and periodic PMSMPR crystallisers were investigated to isolate pure 1:1 and 3:2 p-TSA-TPPO, respectively. Different regions of the ternary diagram of p-TSA, TPPO and acetonitrile (MeCN) were investigated. The desired co-crystal form was isolated all crystallisation platforms investigated. However, greater consistency was observed in the semi-batch and PMSMPR operations respectively. Periodic flow crystallisation in PMSMPR is a promising alternative to conventional continuous MSMPR operation, affording greater degrees of freedom operation, slightly narrower RTD profiles, consistent product crystal quality (size, shape and distribution), longer mean residence times, higher yield and productivity and significant reduction in fouling, encrustation and transfer line blockages over prolonged operating periods. Furthermore, the PMSMPR is a versatile platform that can be used to investigate a range of different molecular systems. Relative to batch operation, the PMSMPR can operate close to equilibrium, however, this is dependent on the system kinetics. In addition, retrofitting of batch crystallisers to operate as PMSMPRS fairly simple and require only subtle changes to the existing design space. The integrated array of PAT sensors consisted of attenuated total reflectance ultra violet/visible spectroscopy (ATR-UV/vis), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), focused beam reflectance measurement (FBRM), particle vision microscopy (PVM) and Raman spectroscopy. The results from the studies reported here illustrate very well the use of PAT and information system tools together to determine when the continuous and periodic MSMPR operations reaches a steady-state or state of controlled operation (i.e. periodic steady-state). These tools provided a better understanding of the variables and operating procedures that influence the two types of operations.
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Schilling, Gordian Hansjoerg. "Algorithms for short-term and periodic process scheduling and rescheduling." Thesis, Imperial College London, 1998. http://hdl.handle.net/10044/1/7696.
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Celik, Mehmet Kemal. "Digital image segmentation using periodic codings." Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/80099.
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Digital image segmentation using periodic codings is explored with reference to two applications. First, the application of uniform periodic codings, to the problem of segmenting the in-focus regions in an image from the blurred parts, is discussed. The work presented in this part extends a previous investigation on this subject by considering the leakage effects. The method proposed consists of two stages. In each stage, filtering is done in the spatial frequency domain after uniform grating functions are applied to the images in the spatial domain. Then, algorithms for finding the period and phase of a physical grating are explored for a hybrid optical-digital application of the method.
Second, a model for textures as the linear superposition of periodic narrowband components, defined as tones, is proposed. A priori information about the number of the tones, their spatial frequencies, and coefficients is necessary to generate tone and texture indicators. Tone indicators are obtained by filtering the image with complex analytical functions defined by the spatial frequencies of the tones present in the image. A criterion for choosing the dimensions of the filter is also provided. Texture indicators are then generated for each texture in the image by applying the a priori information of the tonal coefficients to the filtered images. Several methods for texture segmentation which employ texture indicators are proposed. Finally, examples which illustrate the characteristics of the method are presented.Master of Science
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Abd-Elrady, Emad. "Nonlinear Approaches to Periodic Signal Modeling." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4644.
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Thirugnanasambandam, Mirunalini. "Signal processing techniques for periodic response of mechanical systems." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=110677.
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The importance of characterizing the steady state solution of the equation of motion of systems was well realized early in literature. A variety of analytical and numerical methods have been developed with the aim of obtaining a solution that is not only close to the exact solution but also computationally inexpensive. In the present work, one such numerical method of solution, the Galerkin method, has been used as a template for developing a method (double integration by parts - DIBP) in order to achieve approximate solutions for mechanical systems in general and for systems with non-smooth nonlinearities in particular. While staying in the Galerkin framework, a variety of functions from the Hilbert space of L2([0, T]) were chosen as the basis to describe the solution in a better way. In order to define the solution of systems with unilateral contact terms, a special set of mature mathematical tools from signal processing called wavelets have also been explored.L'intérêt de la caractérisation du régime permanent associé à l'équation du mouvement d'un système est connu depuis longtemps dans la littérature. De nombreuses méthodes numériques et analytiques ont été développées dans le but d'obtenir une solution proche de la solution exacte tout en minimisant les temps de calculs. En s'appuyant sur la méthode de résolution de Galerkin, ce mémoire présente une méthode dite de double intégration par parties (ou méthode DIBP de l'anglais double integration by parts) ayant pour but d'obtenir une approximation de la solution permanente de systèmes mécaniques en général et en particulier de ceux comportant des nonlinéarités discontinues. Dans le cadre du formalisme de Galerkin, plusieurs fonctions de l'espace de Hilbert L2([0, T]) ont été choisies pour former une base apte à la représentation de la solution recherchée. Afin de décrire la solution de systèmes comportant des discontinuités de type contact, des outils mathématiques fréquemment utilisés pour l'analyse de signal, les ondelettes, ont également été utilisés.
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Chapman, Erin L. "Periodic analysis of critical dimension measurements in the photolithography manufacturing process." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0023/MQ52290.pdf.
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Muratov, Askar. "Intra - Organizational Purchasing Synergy : Reengineering of Periodic Price Adjustment (PPA) Process." Thesis, Linnéuniversitetet, Institutionen för ekonomistyrning och logistik (ELO), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-77237.
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Purpose: The purpose is to investigate and analyse the impact of intra-organizational purchasing synergy on periodic price adjustment (PPA) process. Specifically, paper provides a view on how purchasing process synergy through an operational IT platform can increase process reengineering opportunities within PPA. Methodology: So, to fulfil the purpose of the research, the in-depth case study approach is chosen as a strategy that goes along with exploratory nature of the study, aimed at gaining rich insights in the context in which the phenomenon happens. Findings: The findings emphasize the importance of global process standardization and balanced governance among regional affiliates in successful implementation of PPA process synergy. We also identify a set of specific process reengineering needs in PPA such as company wide information sharing, standardization of part specifications and cost bases, and joint world-wide cost reduction activity within global buyer community (BGC). Then it is observed that all these process reengineering initiatives will not be possible without solid and flexible IT infrastructure to improve buyer productivity and support their further development. Research limitations/implications: Primarily, this study was conducted on single in-depth case study which makes it difficult to completely generalize the findings. Next, there are many factors impacting intra-organizational pricing processes besides global synergy projects. In fact, regional and organizational contexts are of high importance, which are addressed but not analysed in detail in the current study. Practical implications: Together, the findings contribute to our understanding of the step-by-step pricing activity from industrial customer perspective and how buyers can improve cost competitiveness through various tangible and commercial part cost reduction activities. Originality/value: Current study has addressed the pricing process from industrial customer perspective. It has two main theoretical contributions: (1) Detailed step-by-step description of PPA process between OEMs and their suppliers happening after SOP; and (2) groundwork for implementation guidance on intra-organizational price revision process synergy.
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Malhis, Luai Mohammed 1964. "Defect detection in periodic VLSI circuits using digital image processing." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/277265.
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A defect detection algorithm applicable for periodic VLSI circuitry is presented in this thesis. Even though the algorithm is based on the reference comparison approach, the periodicity of the circuit eliminates the need for the so called "golden wafer." The suggested algorithm has demonstrated the ability to detect defects of small area (0.023% of the image area). In addition, the algorithm was 93% successful in defect detection and has a false alarm rate of 0.067 per inspected frame, based on testing 20 frames.
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Ringh, Axel. "The Circulant Rational Covariance Extension Problem for a Skew Periodic Stochastic Process." Thesis, KTH, Optimeringslära och systemteori, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-142457.
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The Rational Covariance Extension Problem is a problemin applied mathematics where one tries to find a rational spectral density thatmatches a finite covariance sequence. Applications of this can be used in areaslike speech- and image-processing. This problem has been studied intensivelyover the last decades and recently a related problem, the Circulant RationalCovariance Extension Problem, was solved. This version of the problem dealswith periodic stochastic sequences, and was shown to be a natural way toapproximate the solution to the original problem. Here we look at the specialcase when the process in question is skew-periodic, and show that also in thiscase a unique solution to the problem exists. Moreover we develop numerical solversfor both the periodic and the skew-periodic problem, and use these algorithms toapproximate the spectrum from a speech signal.Det Rationella Kovariansutvidgningsproblemet är ett problem inom tillämpad matematik där man försöker hitta en rationell spektraltäthet som matchar en given sekvens av kovarianser. Tillämpningar av problemet finns inom områden som tal- och bildbehandling. Problemet har studerats intensivt under de senaste decennierna, och nyligen har ett relaterat problem lösts - nämligen det Cirkulära Rationella Kovariansutvidgningsproblemet. I detta problem arbetar man med periodiska stokastiska processer, och lösningen visade sig vara ett naturligt sätt att approximera lösningen till det första problemet. I denna uppsats tittar vi på specialfallet när processen är skev-periodisk, och visar att det även i detta fall finns en unik lösning. Dessutom utvecklas numeriska lösare för både det periodiska och skev-periodiska problemet, och dessa algoritmer används tillslut för att approximera spektrumet för en talsignal.
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Grimminger, Marsha Loth. "PERIODIC TRENDS IN STRUCTURE FUNCTION RELATIONSHIP OF ORGANIC HETEROACENES." UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_diss/850.
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Our group has previously shown that small changes to molecular structure result in large changes to device properties and stability in organic electronic applications. By functionalizing aromatic heteroacenes with group 14 and group 16 elements, it is possible to control morphology and improve stability for a variety of applications such as thin film transistors and solar cells. Functionalization within the heteroacene core led to changes in electronic structure as observed by electrochemistry and light absorption. By substituting down the periodic table, the carbon heteroatom bond length increased, leading to subtle changes in crystal packing. Absorption maxima were red-‐shifted and stability to light decreased. Substitution of group 14 elements to the solubilizing ethynyl groups attached to the heteroacene also had an effect on crystallization and stability. Substitution of silicon with carbon decreased solubility as well as stability to light. Substitution with germanium also decreased stability to light, but close contacts within the crystal structure and solubility in nonpolar organic solvents increased.
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Lu, Yi. "Periodicity and ruin probabilities for compound non-homogeneous Poisson processes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ59274.pdf.
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Al-Lawzi, Mahmod Jasim Mohammed. "The development of adaptive signal processing algorithms for the recovery of periodic signals." Thesis, Cranfield University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.484187.
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Ghaderi, Foad. "Signal processing techniques for extracting signals with periodic structure : applications to biomedical signals." Thesis, Cardiff University, 2010. http://orca.cf.ac.uk/55183/.
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In this dissertation some advanced methods for extracting sources from single and multichannel data are developed and utilized in biomedical applications. It is assumed that the sources of interest have periodic structure and therefore, the periodicity is exploited in various forms. The proposed methods can even be used for the cases where the signals have hidden periodicities, i.e., the periodic behaviour is not detectable from their time representation or even Fourier transform of the signal. For the case of single channel recordings a method based on singular spectrum anal ysis (SSA) of the signal is proposed. The proposed method is utilized in localizing heart sounds in respiratory signals, which is an essential pre-processing step in most of the heart sound cancellation methods. Artificially mixed and real respiratory signals are used for evaluating the method. It is shown that the performance of the proposed method is superior to those of the other methods in terms of false detection. More over, the execution time is significantly lower than that of the method ranked second in performance. For multichannel data, the problem is tackled using two approaches. First, it is assumed that the sources are periodic and the statistical characteristics of periodic sources are exploited in developing a method to effectively choose the appropriate delays in which the diagonalization takes place. In the second approach it is assumed that the sources of interest are cyclostationary. Necessary and sufficient conditions for extractability of the sources are mathematically proved and the extraction algorithms are proposed. Ballistocardiogram (BCG) artifact is considered as the sum of a number of independent cyclostationary components having the same cycle frequency. The proposed method, called cyclostationary source extraction (CSE), is able to extract these components without much destructive effect on the background electroencephalogram (EEG)
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Pathmanathan, Sureka. "A bandlimited step function for use in discrete periodic extension." Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/16281.
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Master of ScienceDepartment of Mathematics
Nathan Albin
A new methodology is introduced for use in discrete periodic extension of non-periodic functions. The methodology is based on a band-limited step function, and utilizes the computational efficiency of FC-Gram (Fourier Continuation based on orthonormal Gram polynomial basis on the extension stage) extension database. The discrete periodic extension is a technique for augmenting a set of uniformly-spaced samples of a smooth function with auxiliary values in an extension region. If a suitable extension is constructed, the interpolating trigonometric polynomial found via an FFT(Fast Fourier Transform) will accurately approximate the original function in its original interval. The discrete periodic extension is a key construction in the FC-Gram algorithm which is successfully implemented in several recent efficient and high-order PDEs solvers. This thesis focuses on a new flexible discrete periodic extension procedure that performs at least as well as the FC-Gram method, but with somewhat simpler implementation and significantly decreased setup time.
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Patel, Gayatri. "How 'universal' is the United Nations' universal periodic review process? : an examination from a cultural relativist perspective." Thesis, University of Leicester, 2016. http://hdl.handle.net/2381/37501.
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This thesis explores the United Nations’ human rights monitoring mechanism, the Universal Periodic Review (UPR) process. The aim of the UPR process is to peer review states’ human rights records through an interactive dialogue session. One of the core elements of the review process is its claim of universality, which is based on two grounds: first, the universal applicability of the process, and second, the normative claim of universalism that is embedded in the operation of the process. Focusing on the second claim of universalism, I challenge the normative claim of universality of the process using the theories of cultural relativism. I ask whether, and to what extent, member states adopt positions that affiliate with the cultural relativist perspective during the interactive dialogue stage in the UPR process. Guided by the theoretical framework of this investigation, I selected three women’s rights categories as the focus of this investigation: women’s rights to health, women’s rights under private and family law and violence against women. The findings of this investigation reveal that there was evidence of states introducing arguments from a form of cultural relativism to challenge universality of international women’s rights. The foundations of this investigation are laid down in the first three chapters of this thesis, which broadly provide details of the UPR process, define the theoretical framework and justify the research methods adopted for this study. Chapters 4, 5 and 6 of this thesis present, analyse and discuss the findings of this research project. Drawing upon the findings, this thesis provides two main conclusions. First, that the extent to which the universality of human rights is promoted is contingent on the states participating in the review and the human rights issue being discussed. Second, an unchecked challenge of universalism expressed by some states from a form of cultural relativism threatens not only the creditability of the UPR process, but could potentially question the very infrastructure of international human rights norms.
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Olsson, Sven. "Signal processing as a tool to enhance productivity in industry : measurement and cancelation of periodic signals /." Karlskrona : Blekinge Institute of Technology, 2006. http://www.bth.se/fou/Forskinfo.nsf/allfirst2/943903fa5c44972dc1257133002f9177?OpenDocument.
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Moon, Bill. "Employment of Crystallographic Image Processing Techniques to Scanning Probe Microscopy Images of Two-Dimensional Periodic Objects." PDXScholar, 2011. https://pdxscholar.library.pdx.edu/open_access_etds/699.
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Thin film arrays of molecules or supramolecules are active subjects of investigation because of their potential value in electronics, chemical sensing, catalysis, and other areas. Scanning probe microscopes (SPMs), including scanning tunneling microscopes (STMs) and atomic force microscopes (AFMs) are commonly used for the characterization and metrology of thin film arrays. As opposed to transmission electron microscopy (TEM), SPMs have the advantage that they can often make observations of thin films in air or liquid, while TEM requires highly specialized techniques if the sample is to be in anything but vacuum. SPM is a surface imaging technique, while TEM typically images a 2D projection of a thin 3D sample. Additionally, variants of SPM can make observations of more than just topography; for instance, magnetic force microscopy measures nanoscale magnetic properties. Thin film arrays are typically two-dimensionally periodic. A perfect, infinite two-dimensionally periodic array is mathematically constrained to belong to one of only 17 possible 2D plane symmetry groups. Any real image is both finite and imperfect. Crystallographic Image Processing (CIP) is an algorithm that Fourier transforms a real image into a 2D array of complex numbers, the Fourier coefficients of the image intensity, and then uses the relationship between those coefficients to first ascertain the 2D plane symmetry group that the imperfect, finite image is most likely to possess, and then adjust those coefficients that are symmetry-related so as to perfect the symmetry. A Fourier synthesis of the symmetrized coefficients leads to a perfectly symmetric image in direct space (when accumulated rounding and calculation errors are ignored). The technique is, thus, an averaging technique over the direct space experimental data that were selected from the thin film array. The image must have periodicity in two dimensions in order for this technique to be applicable. CIP has been developed over the past 40 years by the electron crystallography community, which works with 2D projections from 3D samples. Any periodic sample, whether it is 2D or 3D has an "ideal structure" which is the structure absent any crystal defects. The ideal structure can be considered one average unit cell, propagated by translation into the whole sample. The "real structure" is an actual sample containing vacancies, dislocations, and other defects. Typically the goal of electron and other types of microscopy is examination of the real structure, as the ideal structure of a crystal is already known from X-ray crystallography. High resolution transmission electron microscope image based electron crystallography, on the other hand, reveals the ideal crystal structure by crystallographic averaging. The ideal structure of a 2D thin film cannot be easily in a spatially selective fashion examined by grazing incidence X-ray or low energy electron diffraction based crystallography. SPMs straightforwardly observe thin films in direct space, but SPM accuracy is hampered by blunt or multiple tips and other unavoidable instrument errors. Especially since the film is often of a supramolecular system whose molecules are weakly bonded (via pi bonds, hydrogen bonds, etc.) both to the substrate and to each other, it is relatively easy for a molecule from the film to adhere to the scanning tip during the scan and become part of the tip during subsequent observation. If the thin film array has two-dimensional periodicity, CIP is a unique and effective tool both for image enhancement (determination of ideal structure) and for the quantification of overall instrument error. In addition, if a sample of known 2D periodicity is scanned, CIP can return information about the contribution of the instrument itself to the image. In this thesis we show how the technique is applied to images of two dimensionally periodic samples taken by SPMs. To the best of our knowledge, this has never been done before. Since 2D periodic thin film arrays have an ideal structure that is mathematically constrained to belong to one of the 17 plane symmetry groups, we can use CIP to determine that group and use it for a particularly effective averaging algorithm. We demonstrate that the use of this averaging algorithm removes noise and random error from images more effectively than translational averaging, also known as "lattice averaging" or "Fourier filtering". We also demonstrate the ability to correct systematic errors caused by hysteresis in the scanning process. These results have the effect of obtaining the ideal structure of the sample, averaging out the defects crystallographically, by providing an average unit cell which, when translated, represents the ideal structure. In addition, if one has recorded a scanning probe image of a 2D periodic sample of known symmetry, we demonstrate that it is possible to use the Fourier coefficients of the image transform to solve the inverse problem and calculate the point spread function (PSF) of the instrument. Any real scanning probe instrument departs from the ideal PSF of a Dirac delta function, and CIP allows us to quantify this departure as far as point symmetries are concerned. The result is a deconvolution of the "effective tip", which includes any blunt or multiple tip effects, as well as the effects caused by adhesion of a sample molecule to the scanning tip, or scanning irregularities unrelated to the physical tip. We also demonstrate that the PSF, once known, can be used on a second image taken by the same instrument under approximately the same experimental conditions to remove errors introduced during that second imaging process. The preponderance of two-dimensionally periodic samples as subjects of SPM observation makes the application of CIP to SPM images a valuable technique to extract a maximum amount of information from these images. The improved resolution of current SPMs creates images with more higher-order Fourier coefficients than earlier, "softer" images; these higher-order coefficients are especially amenable to CIP, which can then effectively magnify the resolution improvement created by better hardware. The improved resolution combined with the current interest in supramolecular structures (which although 3D usually start building on a 2D periodic surface) appears to provide an opportunity for CIP to significantly contribute to SPM image processing.
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Portugal, Denise Sodero Vinhas. "Modelagem e programação de sistemas a eventos discretos periodicos." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/261069.
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Orientador: Rafael Santos MendesTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
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Resumo: Uma metodologia para obter um escalonamento cíclico em Sistemas a Eventos Discretos é proposta neste trabalho. Esta metodologia parte de uma rede de Petri que modela minimamente um sistema a eventos discretos funcionando em regime periódico. O método identifica quais são as redes que podem ser tratadas por ele. As redes de Petri tratáveis serão decompostas em subredes identificadas por processos, que são classificados de acordo com suas topologias, o que permite a modelagemdo escalonamento cíclico do sistema através de uma modelagem em programação linear inteira mista. Este modelo em MILP será implementado no software GAMS. Alguns exemplos tirados da literatura serão usados para mostrar e testar a aplicação desta metodologia
Abstract: A methodology to obtain a cyclic scheduling in Discrete Events Systems is proposed in this work. This methodology initializes with a Petri netmodeling a discrete events system functioning with periodic processing. The method identifieswhich are the nets that can be treaties by him. The ¿tractable¿ Petri nets will be decomposed in subnets identified by process, which are classified according to its topologies, that permits us tomodel the cyclic scheduling of the systemby amixed integer linear programming model. This model in MILP will be implemented using software GAMS. Some examples from the literature will be used to show and to test the application of this methodology
Doutorado
Automação Industrial
Doutor em Engenharia Elétrica
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Gursoy, Secil. "Investigation Of The Significance Of Periodicity Information In Speaker Identification." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609468/index.pdf.
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In this thesisgeneral feature selection methods and especially the use of periodicity and aperiodicity information in speaker verification task is searched. A software system is constructed to obtain periodicity and aperiodicity information from speech. Periodicity and aperiodicity information is obtained by using a 16 channel filterbank and analyzing channel outputs frame by frame according to the pitch of that frame. Pitch value of a frame is also found by using periodicity algorithms. Parzen window (kernel density estimation) is used to represent each person&rsquo
s selected phoneme. Constructed method is tested for different phonemes in order to find out its usability in different phonemes. Periodicity features are also used with MFCC features to find out their contribution to speaker identification problem.
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Martins, Milena Ribeiro. "Quem conta um conto... aumenta, diminui, modifica : o processo de escrita do conto lobatiano." [s.n.], 1998. http://repositorio.unicamp.br/jspui/handle/REPOSIP/269090.
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Orientador: Enid Yatsuda FredericoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Estudos da Linguagem
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Resumo: Desenvolvemos, nesta dissertação, uma análise do processo de escrita dos contos de Monteiro Lobato, a partir de um corpus constituído pelos 29 contos publicados na Revista do Brasil entre 1916 e 1923. As diferenças entre a publicação em periódico e a edição em livro, além da distância temporal entre as diferentes edições de suas obras, foram algumas das principais motivações para a alteração destes contos. Depois de publicados, todos eles foram constantemente modificados, até que a edição definitiva, a das Obras Completas, pôs um ponto final no trabalho do escritor. A revista (assim como as edições anteriores às Obras Completas) servia, então, como uma prova tipográfica: modificando o texto impresso, Lobato multiplicaria o número de versões dos contos a cada nova edição. Registros desse processo de constante reescrita estão em sua correspondência, a' qual, no entanto, nem sempre pode ser tomada como expressão da verdade. É através das diferentes versões de cada conto, e também de informações contidas na correspondência, que buscamos a compreensão deste processo
Abstract: Not informed.
Mestrado
Teoria Literaria
Mestre em Letras
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Vengattaramane, Kameswaran. "Efficient Reconstruction of Two-Periodic Nonuniformly Sampled Signals Applicable to Time-Interleaved ADCs." Thesis, Linköping University, Department of Electrical Engineering, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-6253.
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Nonuniform sampling occurs in many practical applications either intentionally or unintentionally. This thesis deals with the reconstruction of two-periodic nonuniform signals which is of great importance in two-channel time-interleaved analog-to-digital converters. In a two-channel time-interleaved ADC, aperture delay mismatch between the channels gives rise to a two-periodic nonuniform sampling pattern, resulting in distortion and severely affecting the linearity of the converter. The problem is solved by digitally recovering a uniformly sampled sequence from a two-periodic nonuniformly sampled set. For this purpose, a time-varying FIR filter is employed. If the sampling pattern is known and fixed, this filter can be designed in an optimal way using least-squares or minimax design. When the sampling pattern changes now and then as during the normal operation of time-interleaved ADC, these filters have to be redesigned. This has implications on the implementation cost as general on-line design is cumbersome. To overcome this problem, a novel time-varying FIR filter with polynomial impulse response is developed and characterized in this thesis. The main advantage with these filters is that on-line design is no longer needed. It now suffices to perform only one design before implementation and in the implementation it is enough to adjust only one variable parameter when the sampling pattern changes. Thus the high implementation cost is decreased substantially.
Filter design and the associated performance metrics have been validated using MATLAB. The design space has been explored to limits imposed by machine precision on matrix inversions. Studies related to finite wordlength effects in practical filter realisations have also been carried out. These formulations can also be extended to the general M - periodic nonuniform sampling case.
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Baweja, Randeep Singh. "FPGA Implementation of a Pseudo-Random Aggregate Spectrum Generator for RF Hardware Test and Evaluation." Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/100325.
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Test and evaluation (TandE) is a critically important step before in-the-field deployment of radio-frequency (RF) hardware in order to assure that the hardware meets its design requirements and specifications. Typically, TandE is performed either in a lab setting utilizing a software simulation environment or through real-world field testing. While the former approach is typically limited by the accuracy of the simulation models (particularly of the anticipated hardware effects) and by non-real-time data rates, the latter can be extremely costly in terms of time, money, and manpower. To build upon the strengths of these approaches and to mitigate their weaknesses, this work presents the development of an FPGA-based TandE tool that allows for real-time pseudo-random aggregate signal generation for testing RF receiver hardware (such as communication receivers, spectrum sensors, etc.). In particular, a framework is developed for an FPGA-based implementation of a test signal emulator that generates randomized aggregate spectral environments containing signals with random parameters such as center frequencies, bandwidths, start times, and durations, as well as receiver and channel effects such as additive white Gaussian noise (AWGN). To test the accuracy of the developed spectrum generation framework, the randomization properties of the framework are analyzed to assure correct probability distributions and independence. Additionally, FPGA implementation decisions, such as bit precision versus accuracy of the generated signal and the impact on the FPGA's hardware footprint, are analyzed.This analysis allows the test signal engineer to make informed decisions while designing a hardware-based RF test system. This framework is easily extensible to other signal types and channel models, and can be used to test a variety of signal-based applications.Master of Science
Test and evaluation (TandE) is a critically important step before in-the-field deployment of radio-frequency signal hardware in order to assure that the hardware meets its design requirements and specifications. Typically, TandE is performed either in a lab setting utilizing a software simulation or through real-world field testing. While the former approach is typically limited by the accuracy of the simulation models and by slower data rates, the latter can be extremely costly in terms of time, money, and manpower. To address these issues, a hardware-based signal generation approach that takes the best of both methods mentioned above is developed in this thesis. This approach allows the user to accurately model a radio-frequency system without requiring expensive equipment. This work presents the development of a hardware-based TandE tool that allows for real-time random signal generation for testing radio-frequency receiver hardware (such as communication receivers). In particular, a framework is developed for an implementation of a test signal emulator that allows for user-defined randomization of test signal parameters such as frequencies, signal bandwidths, start times, and durations, as well as communications receiver effects. To test the accuracy of the developed emulation framework, the randomization properties of the framework are analyzed to assure correct probability distributions and independence. Additionally, hardware implementation decisions such as bit precision versus quality of the generated signal and the impact on the hardware footprint are analyzed. Ultimately, it is shown that this framework is easily extensible to other signal types and communication channel models.
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Pospíšil, Tomáš. "STOCHASTIC MODELING OF COMPOSITE MATERIALS." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-233889.
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Práce je věnována generování náhodných struktur dvousložkových vláknových kompozitních materiálů a statistickým metodám analýzy náhodnosti těchto struktur. Byly vyvinuty čtyři algoritmy a vygenerované struktury byly statisticky porovnány s reálnými daty.
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Klein-Hennig, Martin [Verfasser], Volker [Akademischer Betreuer] Hohmann, and Birger [Akademischer Betreuer] Kollmeier. "Binaural auditory processing and temporal periodicity: experiments and models / Martin Klein-Hennig. Betreuer: Volker Hohmann ; Birger Kollmeier." Oldenburg : BIS der Universität Oldenburg, 2014. http://d-nb.info/1067557539/34.
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Klein-Hennig, Martin Verfasser], Volker [Akademischer Betreuer] Hohmann, and Birger [Akademischer Betreuer] [Kollmeier. "Binaural auditory processing and temporal periodicity: experiments and models / Martin Klein-Hennig. Betreuer: Volker Hohmann ; Birger Kollmeier." Oldenburg : BIS der Universität Oldenburg, 2014. http://nbn-resolving.de/urn:nbn:de:gbv:715-oops-23293.
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Mai, Cuong. "Frequency Estimation Using Time-Frequency Based Methods." ScholarWorks@UNO, 2007. http://scholarworks.uno.edu/td/571.
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Any periodic signal can be decomposed into a sum of oscillating functions. Traditionally, cosine and sine segments have been used to represent a single period of the periodic signal (Fourier Series). In more general cases, each of these functions can be represented by a set of spectral parameters such as its amplitude, frequency, phase, and the variability of its instantaneous spectral components. The accuracy of these parameters depends on several processing variables such as resolution, noise level, and bias of the algorithm used. This thesis presents some background of existing frequency estimation techniques and proposes a new technique for estimating the instantaneous frequency of signals using short sinusoid-like basis functions. Furthermore, it also shows that the proposed algorithm can be implemented in a popular embedded DSPmicroprocessor for practical use. This algorithm can also be implemented using more complex features on more resourceful processing processors in order to improve estimation accuracy
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Vinberg, Karl, Jacob Holm, and Amer Basic. "Från periodisk inventering utan Pick By Voice till rullande inventering med Pick By Voice : En fallstudie på Företag X." Thesis, Linnéuniversitetet, Institutionen för ekonomistyrning och logistik (ELO), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-96750.
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Titel: Från periodisk inventering utan Pick By Voice till rullande inventering med Pick By Voice - En fallstudie på Företag X Bakgrund och problem: Företag X har valt att implementera plocktekniken Pick By Voice, samtidigt som företaget ser över möjligheten att implementera en rullande inventering i samband med detta. Frågor som uppstår är vad lagar och praxis säger för området samt hur en möjlig implementering av rullande inventering bör se ut. Syfte: Syftet med uppsatsen är att genom en kvalitativ studie undersöka behovet av en ny inventeringsmetod genom en förstudie och därefter utveckla en inventeringsprocess passande efter Företag X förutsättningar. Denna inventeringsprocess ska kunna användas i samspel med Pick By Voice. Vidare är också att uppmuntra andra företag inom likartad bransch att se över sin nuvarande inventeringsmetod och om de kan implementera en liknande förändring av rullande inventering med Pick By Voice. Metod: Denna studie är en kvalitativ fallstudie. Insamlingen av empiri har skett genom utförandet av semistrukturerade och ostrukturerade intervjuer med företag och revisionsbyråer. Slutsats: En nu 65 år gammal skattelag säger att företag måste inventera sina lager minst en gång om året. Som en otillräcklig beskrivning av hur detta ska göras, samtidigt som lagerhanteringssystemet får ny utveckling, har detta lagt större vikt vid nuvarande praxis. Detta är särskilt så när ett företag implementerar en rullande inventeringsmetod. Viktiga steg i implementeringsprocessen bekräftas vara avgörande för företag att uppfylla. Dels för att lyckas med implementeringen, men också för att säkerställa en tillfredsställande inventeringsprocess och undvika att både misstag i implementerings- och inventeringssprocessen uppstår. Att kombinera den rullande inventeringen med röstplocktekniken Pick By Voice anses även det vara betydande för att reducera ytterligare misstag som förekommer eller kan förekomma i inventeringsprocessen. Hur frekvent företag bör inventera grundar sig i; vilken typ av marknad företaget är verksamt på, andelen misstag som uppstår i inventeringsprocessen och om fler antal inventeringar kan bidra till fler besparingar för företaget.Title: From periodic inventory without Pick By Voice to continuous inventory with Pick By Voice - A case study at Company X Background and problem: Company X has chosen to implement the Pick By Voice picking technology, while at the same time considering the possibility of implementing a continuous inventory in connection with this. Questions that arise are what the laws and practices say for this area and what a possible implementation of continuous inventory should look like. Purpose: The purpose of this thesis is to investigate the need for a new inventory method through a pilot study and then develop an inventory process suitable for Company X conditions. This inventory process should be used in interaction with Pick By Voice. Furthermore, other companies in similar industries are also encouraged to review their current inventory method and whether they can implement a similar change of continuous inventory with Pick By Voice. Method: This study is a qualitative case study. The collection of empirical data has been carried out through the conduct of semi structured and unstructured interviews with companies and accounting firms. Conclusion: A now 65 years old tax law says that companies need to count their inventory at least once a year. As there is an insufficient description of how this should be done, while also warehouse management system get new development, this has placed greater emphasis on current practice. This so, especially when a company is implementing a continuous inventory method with Pick By Voice. Important steps in the implementation process have been confirmed to be crucial to fulfil by the company. Especially in order to achieve a successful implementation of the process, ensure that the process fulfil its required satisfaction level and to avoid occurrence of mistakes in the implementation process as well as in the inventory process. The combination of continuous inventory and Pick By Voice is considered to be significant in the reduction of further mistakes that occur or can occur in the inventory process. The determination of the inventory frequency is dependent on; type of market that the company operates in, number of occurring mistakes in the inventory process and if an increase in number of inventory occasions can contribute to an increase in the savings.
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Inam, Ul Haq Muhammad. "Texture analysis in the Logarithmic Image Processing (LIP) framework." Phd thesis, Université Jean Monnet - Saint-Etienne, 2013. http://tel.archives-ouvertes.fr/tel-00998492.
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This thesis looks at the evaluation of textures in two different perspectives using logarithmic image processing (LIP) framework. The first case after introducing the concept of textures and giving some classical approaches of textures evaluation, it gives an original approach of textures evaluation called covariogram which is derived from similarity metrics like distances or correlations etc. The classical covariogram which is derived from the classical similarity metrics and LIP covariogram are then applied over several images and the efficiency of the LIP one is clearly shown for darkened images. The last two chapters offer a new approach by considering the gray levels of an image as the phases of a medium. Each phase simulates like a percolation of a liquid in a medium defining the percolation trajectories. The propagation from one pixel to another is taken as easy or difficult determined by the difference of the gray level intensities. Finally different parameters like fractality from fractal dimensions, mean histogram etc associated to these trajectories are derived, based on which the primary experiment for the classification of random texture is carried out determining the relevance of this idea. Obviously, our study is only first approach and requires additional workout to obtain a reliable method of classification
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Guilak, Farzin G. "A Spline Framework for Optimal Representation of Semiperiodic Signals." Thesis, Portland State University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3722040.
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Semiperiodic signals possess an underlying periodicity, but their constituent spectral components include stochastic elements which make it impossible to analytically determine locations of the signal's critical points. Mathematically, a signal's critical points are those at which it is not differentiable or where its derivative is zero. In some domains they represent characteristic points, which are locations indicating important changes in the underlying process reflected by the signal.
For many applications in healthcare, knowledge of precise locations of these points provides key insight for analytic, diagnostic, and therapeutic purposes. For example, given an appropriate signal they might indicate the start or end of a breath, numerous electrophysiological states of the heart during the cardiac cycle, or the point in a stride at which the heel impacts the ground. The inherent variability of these signals, the presence of noise, and often, very low signal amplitudes, makes accurate estimation of these points challenging.
There has been much effort in automatically estimating characteristic point locations. Approaches include algorithms operating in the time domain, on various transformations of the data, and using different models of the signal. These methods apply a wide variety of techniques ranging from simple thresholds and search windows to sophisticated signal processing and pattern recognition algorithms. Existing approaches do not explicitly use prior knowledge of characteristic point locations in their estimation.
This dissertation first develops a framework for an efficient parametric representation of semiperiodic signals using splines. It then implements an instance of that framework to optimally estimate locations of characteristic points, incorporating prior knowledge from manual annotations on training data. Splines represent signals in a piecewise manner by applying an interpolant to constraint points on the signal known as knots. The framework allows choice of interpolant, objective function, knot initialization algorithm, and optimization algorithm. After initialization it iteratively modifies knot locations until the objective function is met.
For optimal estimation of characteristic points the framework relies on a Bayesian objective function, the a posteriori probability of knot locations given the observed signal. This objective function fuses prior knowledge, the observed signal, and its spline estimate. With a linear interpolant, knot locations after optimization serve as estimates of the signal's characteristic points.
This implementation was used to determine locations of 11 characteristic points on a prospective test set comprising 200 electrocardiograph (ECG) signals from 20 subjects. It achieved a mean error of -0.4 milliseconds, less than one quarter of a sample interval. A low bias is not sufficient, however, and the literature recognizes error variance to be the more important factor in assessing accuracy. Error variances are typically compared to the variance of manual annotations provided by reviewers. The algorithm was within two standard deviations for six of the characteristic points, and within one sample interval of this criterion for another four points.
The spline framework described here provides a complementary option to existing methods for parametric modeling of semiperiodic signals, and can be tailored to represent semiperiodic signals with high fidelity or to optimally estimate locations of their characteristic points.
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Jaron, Frédéric Felix Daniel [Verfasser]. "Physical processes behind the periodic radio and gamma-ray emission from the X-ray binary LS I +61°303 / Frédéric Felix Daniel Jaron." Bonn : Universitäts- und Landesbibliothek Bonn, 2016. http://d-nb.info/1113688394/34.
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Payan, Alexia Paule Marie-Renee. "Uncovering local magnetospheric processes governing the morphology and periodicity of Ganymede’s aurora using three-dimensional multifluid simulations of Ganymede’s magnetosphere." Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/51756.
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The electrodynamic interaction of Ganymede’s mini-magnetosphere with Jupiter’s corotating magnetospheric plasma has been shown to give rise to strong current systems closing through the moon and its ionosphere as well as through its magnetopause and magnetotail current sheet. This interaction is strongly evidenced by the presence of aurorae at Ganymede and of a bright Ganymede footprint on Jupiter’s ionosphere. This footprint is located equatorward of the main auroral emissions, at the magnetic longitude of the field line threading Ganymede. The brightness of Ganymede’s auroral footprint at Jupiter along with its latitudinal position have been shown to depend on the position of Ganymede relative to the center of the Jovian plasma sheet. Additionally, observations using the Hubble Space Telescope showed that Ganymede’s auroral footprint brightness is characterized by variations of three different timescales: 5 hours, 10-40 minutes, and ~100 seconds. The goal of the present study is to examine the relationship between the longest and the shortest timescale periodicities of Ganymede’s auroral footprint brightness and the local processes occurring at Ganymede. This is done by coupling a specifically developed brightness model to a three-dimensional multifluid model which tracks the energies and fluxes of the various sources of charged particles that precipitate into Ganymede’s ionosphere to generate the aurora. It is shown that the predicted auroral brightnesses and morphologies agree well with observations of Ganymede’s aurora from the Hubble Space Telescope. Our results also suggest the presence of short- and long-period variabilities in the auroral emissions at Ganymede due to magnetic reconnections on the magnetopause and in the magnetotail, and support the hypothesis of a correlation between the variability of Ganymede’s auroral footprint on Jupiter’s ionosphere and the variability in the brightness and morphology of the aurora at Ganymede. Finally, the modeled aurora at Ganymede reveals that the periodicities in the morphology and brightness of the auroral emissions are produced by two different dynamic reconnection mechanisms. The Jovian flow facing side aurora is generated by electrons sourced in the Jovian plasma and penetrating into Ganymede’s ionosphere through the cusps above the separatrix region. In this case, the reconnection processes responsible for the auroral emissions occur on Ganymede’s magnetopause between the Jovian magnetic field lines and the open magnetic field lines threading Ganymede’s Polar Regions. As for the magnetotail side aurora, it is generated by electrons originating from Ganymede’s magnetospheric flow. These electrons are accelerated along closed magnetic field lines created by magnetic reconnection in Ganymede’s magnetotail, and precipitate into Ganymede’s ionosphere at much lower latitudes, below the separatrix region.
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Yeung, Deryck. "Maximally smooth transition: the Gluskabi raccordation." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42756.
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The objective of this dissertation is to provide a framework for constructing a transitional behavior, connecting any two trajectories from a set with a particular characteristic, in such a way that the transition is as inconspicuous as possible. By this we mean that the connection is such that the characteristic behavior persists during the transition. These special classes include stationary solutions, limit cycles etc. We call this framework the Gluskabi raccordation. This problem is motivated from physical applications where it is often desired to steer a system from one stationary solution or periodic orbit to another in a ̒smooth̕ way. Examples include motion control in robotics, chemical process control and quasi-stationary processes in thermodynamics, etc. Before discussing the Gluskabi raccordations of periodic behaviors, we first study several periodic phenomena. Specifically, we study the self- propulsion of a number of legless, toy creatures based on differential friction under periodic excitations. This friction model is based on viscous friction which is predominant in a wet environment. We investigate the effects of periodic and optimal periodic control on locomotion. Subsequently, we consider a control problem of a stochastic system, under the basic constraint that the feedback control signal and the observations from the system cannot use the communication channel simultaneously. Hence, two modes of operation result: an observation mode and a control mode. We seek an optimal periodic regime in a statistical steady state by switching between the observation and the control mode. For this, the duty cycle and the optimal gains for the controller and observer in either mode are determined.
We then investigate the simplest special case of the Gluskabi raccordation, namely the quasi-stationary optimal control problem. This forces us to revisit the classical terminal controller. We analyze the performance index as the control horizon increases to infinity. This problem gives a good example where the limiting operation and integration do not commute. Such a misinterpretation can lead to an apparent paradox. We use symmetrical components (the parity operator) to shed light on the correct solution.
The main part of thesis is the Gluskabi raccordation problem. We first use several simple examples to introduce the general framework. We then consider the signal Gluskabi raccordation or the Gluskabi raccordation without a dynamical system. Specifically, we present the quasi-periodic raccordation where we seek the maximally ̒smooth̕ transitions between two periodic signals. We provide two methods, the direct and indirect method, to construct these transitions. Detailed algorithms for generating the raccordations based on the direct method are also provided. Next, we extend the signal Gluskabi raccordation to the dynamic case by considering the dynamical system as a hard constraint. The behavioral modeling of dynamical system pioneered by Willems provides the right language for this generalization. All algorithms of the signal Gluskabi raccordation are extended accordingly to produce these ̒smooth̕ transition behaviors.
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Tikarrouchine, El-Hadi. "Simulation multi-échelles par EF² de structures composites périodiques en régime viscoélastique-viscoplastique- endommageable avec couplage thermomécanique fort." Thesis, Paris, ENSAM, 2019. http://www.theses.fr/2019ENAM0032/document.
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Une approche de simulation numérique multi-échelles EF2 fondée sur la théorie de l'homogénéisation périodique a été développée pour prédire la réponse globale couplée mécanique et thermomécanique fortement non linéaire des structures composites 3D. La stratégie de calcul intègre les effets de la microstructure périodique en introduisant l'architecture des renforts et les lois constitutives locales. Les lois de comportement des constituants utilisées obéissent aux lois de matériaux standards généralisées et sont formulées dans un cadre de la thermodynamique des processus irréversibles (TPI). Les équations caractéristiques (équilibre et lois de la thermodynamique) sont formulées sous l'hypothèse des petites déformations et rotations, et résolues simultanément de façon incrémentale aux deux échelles (microscopique et macroscopique). Sur le plan numérique, une implémentation au moyen de routines UMAT imbriquées (Méta-UMAT) a été développée et combinée à une technique de parallélisation dans le code de calcul Abaqus/Standard. La stratégie de calcul multi-échelles est appliquée pour simuler la réponse globale de structures composites 3D soumises à des trajets de chargement thermomécaniques complexes. Les structures composites sont constituées d’une matrice polymère thermoplastique viscoélastique-viscoplastic avec endommagement ductile et renforcées par différents types de renforcements (fibres courtes ou tissus). L’endommagement anisotrope dans les torons de tissu est modélisé à travers une approche micromécanique permettant de suivre l’évolution de la densité de micro-fissures transverses. Cette stratégie de calcul peut être déployée sur les structures en matériaux composites ayant une microstructure périodique et dont les phases présentent différents types des lois de comportement non linéaires (rhéologie, mécanismes d'endommagement et couplage thermomécanique). Les capacités de l'approche multi-échelles sont démontrées en comparant les prédictions numériques aux résultats expérimentaux en termes de réponse globale et de champs de déformation macroscopiques et microscopiques. Les performances de l'approche sont également illustrées à travers l'accès aux répartitions spatio-temporelles des variables internes à l'échelle de la microstructure ainsi que la dissipation intrinsèque dans les phases constitutivesA multi-scale FE2 approach based on the periodic homogenization theory is developed to predict the overall response of nonlinear mechanical and fully coupled thermomechanical 3D composite structures. The computational strategy integrates the periodic microstructure effects by introducing the architecture of the reinforcement and the local constitutive laws.The considered constituents' constitutive laws obey generalized standard materials laws and are formulated within the framework of thermodynamics of irreversible processes. The characteristic equations (equilibrium and thermodynamics laws) are formulated under the assumption of small strains and rotations. They are solved simultaneously at both scales (microscopic and macroscopic) using an incremental scheme. For the numerical implementation, an advanced Meta-UMAT subroutine is developed and combined with a parallelization technique in the finite element commercial software Abaqus/Standard. The multi-scale computational strategy is applied to simulate the overall response of 3D composite structures under complex thermomechanical loading paths. The composite structures consist of thermoplastic polymer matrix with viscoelastic-viscoplastic behavior and ductile damage, reinforced by different types of reinforcements (short fibers or woven fabrics). The anisotropic damage within the yarns is modeled through a micromechanical approach to follow the transverse micro-cracks density evolution. This computational strategy is deployed on composite structures having periodic microstructure, whose phases exhibit different types of nonlinear behavior laws (rheology, damage mechanisms and thermomechanical coupling). The capabilities of the multi-scale approach are demonstrated (i) by comparing numerical predictions with experimental results in terms of global response, macroscopic and microscopic strain fields, and (ii) through the access to spatio-temporal distributions of internal variables at the microstructure scale as well as the intrinsic dissipation in the constitutive phases
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Gouyon, Fabien. "A computational approach to rhythm description - Audio features for the computation of rhythm periodicity functions and their use in tempo induction and music content processing." Doctoral thesis, Universitat Pompeu Fabra, 2005. http://hdl.handle.net/10803/7484.
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Aquesta dissertació tracta del ritme musical. Més exactamente, tracta de programes informàtics que extreuen automàticament descripcions rítmiques a partir de senyals musicals d'àudio.Presentem nous algorismes per a la inducció del tempo, la estimació del "tatum," la determinació del compàs, la estimació de "swing," transformacions de "swing" i la classificació d'estils de música de ball. Aquests algorismes processen directament gravacions digitalitzades de senyals acústiques de música. La base d'aquests algorismes son funcions de periodicitat rítmica: es a dir, funcions que mesuren la importància d'una pulsació rítmica en funció del període (o la freqüència) de la mateixa, calculades a partir d'atributs físics instantanis seleccionats per a posar en evidència aspectes rítmics del só. Aquests atributs es calculen amb una freqüència de mostreig constant sobre segments curts de la senyal d'àudio.
Els nostres algorismes determinen el tempo i el "tatum" de música de diferents estils musicals, amb tempo constant, amb una precisió de més del 80% si no insistim en trobar el nivell mètric específic. Indentifiquen el compàs amb una precisió del 90%, si es coneixen nivells mètrics més ràpits. Classifiquen música de ball en 8 categories amb una precisió del 80% tenint en compte únicament aspectes rítmics de la música. Finalment, afegeixen (o substreuen) el "swing" de senyals musicals d'àudio de manera automàtica, conservant una alta qualitat de só.
Des d'un punt de vista més general, aquesta dissertació contribueix de manera significativa al camp de la descripció computacional del ritme a) en proposar un entorn unificador d'analisi funcional; b) en revisar l'arquitectura de molts sistemes existent respecte els blocs funcionals d'aquest entorn; c) en organitzar la primera evaluació pública d'algorismes d'inducció de tempo; i d) en identificar direccions de recerca prometedores, particularment respecte a la selecció d'atributs instantanis més adients per al càlcul de funcions de periodicitat rítmica útils i l'estrategia per a combinar i processar multiples fonts d'informació rítmica.
Esta disertación trata del ritmo musical. Más precisamente, trata de programas informáticos que extraen automáticamente descripciones rítmicas a partir de señales musicales de audio.
Presentamos nuevos algoritmos para la inducción del tempo, la estimación del "tatum," la determinación del compás, la estimación del "swing," transformaciones de "swing" y la clasificación de estilos de música de baile. Estos algoritmos procesan directamente grabaciones digitalizadas de señales acústicas de música. La base de estos algoritmos son funciones de periodicidad rítmica: funciones que miden la importancia de una pulsación rítmica en función del periodo (o la frecuencia) de la misma, calculadas a partir de atributos físicos instantáneos seleccionados para poner en evidencia aspectos rítmicos del sonido. Estos atributos se calculan con una frecuencia de muestreo constante sobre segmentos cortos de la señal de audio.
Nuestros algoritmos determinan el tempo y el "tatum" de música de diferentes géneros, con tempo casi constante, con una precisión de más de 80% si no insistimos en encontrar un nivel métrico específico. Identifican el compás con una precisión de 90%, si se conocen niveles métricos más rápidos. Clasifican música de baile en 8 categorías con una precisión de 80% tomando en cuenta solamente aspectos rítmicos de la música. Finalmente, añaden (o sustraen) el "swing" de señales musicales de audio de manera automática, conservando una cualidad de sonido muy buena.
De un punto de vista más general, está disertación contribuye de manera significativa al campo de la descripción computacional del ritmo a) en proponer un entorno unificador de análisis funcional; b) en revisar la arquitectura de muchos sistemas existentes respecto a los bloques funcionales de este entorno; c) en organizar la primera evaluación pública de algoritmos de inducción del tempo; y d) en identificar direcciones de investigación prometedoras, particularmente respecto a la selección de los mejores atributos instantáneos para el cálculo de funciones de periodicidad rítmica útiles y la estrategia para combinar y procesar múltiples fuentes de información rítmica.
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Crestani, Jaison Luís. "Machado de Assis e o processo de criação literária : estudo comparativo das narrativas publicadas n'A Estação (1879- 1884), na Gazeta de Notícias (1881-1884) e nas coletâneas Papéis avulsos (1882) e Histórias sem data (1884)." Assis : [s.n.], 2011. http://hdl.handle.net/11449/103629.
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Orientador: Álvaro Santos Simões JuniorBanca: Sílvia Maria Azevedo
Banca: Daniela Mantarro Calippo
Banca: Valentim Aparecido Facioli
Banca: Regina Célia dos Santos Alves
Resumo: Esta tese apresenta um estudo crítico e comparativo dos contos de Machado de Assis publicados entre 1879 e 1884 em três diferentes contextos de produção: a revista A Estação (1879-1884), o jornal Gazeta de Notícias (1881-1884) e as coletâneas Papéis avulsos (1882) e Histórias sem data (1884). Paralelamente ao trabalho de retomada das fontes primárias e das condições de produção literária na imprensa periódica, esta pesquisa propõe um questionamento das duas correntes básicas da fortuna crítica machadiana, que sustentam as teses de que a trajetória criativa de Machado de Assis se define por uma "ruptura radical" ou por um "amadurecimento progressivo" entre as fases de produção. Partindo dessa problematização, pretende-se redefinir as perspectivas de análise de modo a tornar possível a percepção da complexidade do percurso do escritor e dos delineamentos criativos de sua ficção, que evidenciam um movimento alternado entre experimentação, aprimoramento, repetição, descontinuidade e legitimação de soluções temáticas, procedimentos formais e orientações estéticas. Com base na constituição versátil e multiforme assumida pela sua colaboração nesses dois periódicos, propõe-se averiguar a tese de que a criação machadiana se configura a partir das especificidades materiais e das demandas disponíveis em cada contexto (livro, revista e jornal), orientando-se por um transitar simultâneo do autor entre as esferas do passatempo e da artisticidade, do prosaísmo e da complexidade, da reiteração de fórmulas testadas e do esboço de proposições inovadoras
Abstract: This research suggests a critical and comparative study of Machado de Assis's tales published, between the years 1879 and 1884, under three different production contexts: the magazine A Estação (1879-1884), the newspaper Gazeta de Notícias (1881-1884) and the collections Papéis avulsos (1882) and Histórias sem data (1884). In parallel to the duty of searching of the primary sources and the literary production conditions in the periodic press, this research proposes a questioning of the two basical flows of machadiana critical fortune, which sustains the thesis that the creative trajectory of Machado de Assis defines itself by a "radical rupture" or by a "progressive maturing" between the production stages. Starting at this problematic, it's intended to redefine the analysis perspectives in a way to make possible the perception of the complexity of the writer's way and the creative boundaries of his fiction evidencing an alternate movement among the experimentation, enhancing, repetition, noncontinuing and legitimation of the tematic solutions, formal procedures and esthetical orientations. Based on the versatil and multiform constitution assumed by his cooperation in theses two periodics, it's proposed to certify that the machadiana thesis of creation configurates itself under the material especifities and available demandings in each context (book, magazine, newspaper), guiding itself in a simultaneous journey on the author among the espheres of passtime and arsticity, the prozaism and complexity, repetition of tested formulae and the draft of innovative propositions
Doutor
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Crestani, Jaison Luís [UNESP]. "Machado de Assis e o processo de criação literária: estudo comparativo das narrativas publicadas n’A Estação (1879- 1884), na Gazeta de Notícias (1881-1884) e nas coletâneas Papéis avulsos (1882) e Histórias sem data (1884)." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/103629.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Esta tese apresenta um estudo crítico e comparativo dos contos de Machado de Assis publicados entre 1879 e 1884 em três diferentes contextos de produção: a revista A Estação (1879-1884), o jornal Gazeta de Notícias (1881-1884) e as coletâneas Papéis avulsos (1882) e Histórias sem data (1884). Paralelamente ao trabalho de retomada das fontes primárias e das condições de produção literária na imprensa periódica, esta pesquisa propõe um questionamento das duas correntes básicas da fortuna crítica machadiana, que sustentam as teses de que a trajetória criativa de Machado de Assis se define por uma “ruptura radical” ou por um “amadurecimento progressivo” entre as fases de produção. Partindo dessa problematização, pretende-se redefinir as perspectivas de análise de modo a tornar possível a percepção da complexidade do percurso do escritor e dos delineamentos criativos de sua ficção, que evidenciam um movimento alternado entre experimentação, aprimoramento, repetição, descontinuidade e legitimação de soluções temáticas, procedimentos formais e orientações estéticas. Com base na constituição versátil e multiforme assumida pela sua colaboração nesses dois periódicos, propõe-se averiguar a tese de que a criação machadiana se configura a partir das especificidades materiais e das demandas disponíveis em cada contexto (livro, revista e jornal), orientando-se por um transitar simultâneo do autor entre as esferas do passatempo e da artisticidade, do prosaísmo e da complexidade, da reiteração de fórmulas testadas e do esboço de proposições inovadoras
This research suggests a critical and comparative study of Machado de Assis’s tales published, between the years 1879 and 1884, under three different production contexts: the magazine A Estação (1879-1884), the newspaper Gazeta de Notícias (1881-1884) and the collections Papéis avulsos (1882) and Histórias sem data (1884). In parallel to the duty of searching of the primary sources and the literary production conditions in the periodic press, this research proposes a questioning of the two basical flows of machadiana critical fortune, which sustains the thesis that the creative trajectory of Machado de Assis defines itself by a “radical rupture” or by a “progressive maturing” between the production stages. Starting at this problematic, it’s intended to redefine the analysis perspectives in a way to make possible the perception of the complexity of the writer’s way and the creative boundaries of his fiction evidencing an alternate movement among the experimentation, enhancing, repetition, noncontinuing and legitimation of the tematic solutions, formal procedures and esthetical orientations. Based on the versatil and multiform constitution assumed by his cooperation in theses two periodics, it’s proposed to certify that the machadiana thesis of creation configurates itself under the material especifities and available demandings in each context (book, magazine, newspaper), guiding itself in a simultaneous journey on the author among the espheres of passtime and arsticity, the prozaism and complexity, repetition of tested formulae and the draft of innovative propositions
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Huang, Shu. "Investigating multiphoton phenomena using nonlinear dynamics." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22558.
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Thesis (Ph. D.)--Physics, Georgia Institute of Technology, 2008.Committee Chair: Uzer, Turgay; Committee Member: Aral, Mustafa; Committee Member: Flannery, Raymond; Committee Member: Raman, Chandra; Committee Member: Schatz, Michael.
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Laborde-Zubieta, Patxi. "Combinatoire de l’ASEP, arbres non-ambigus et polyominos parallélogrammes périodiques." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0709/document.
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Cette thèse porte sur l’interprétation combinatoire des probabilitésde l’état stationnaire de l’ASEP par les tableaux escaliers, sur les arbresnon-ambigus et sur les polyominos parallélogrammes périodiques.Dans une première partie, nous étudions l’ansatz matriciel de Derrida,Evans, Hakim et Pasquier. Toute solution de ce système d’équation permet decalculer les probabilités stationnaires de l’ASEP. Nos travaux définissent denouvelles récurrences équivalentes à celles de l’ansatz matriciel. En définissantun algorithme d’insertion sur les tableaux escaliers, nous montrons combinatoirementet simplement qu’ils les satisfont. Nous faisons de même pour l’ASEPà deux particules. Enfin, nous énumérons les coins dans les tableaux associésà l’ASEP, nous permettant ainsi de donner le nombre moyen de transitionspossibles depuis un état de l’ASEP.Dans une deuxième partie, nous calculons de jolies formules pour les sériesgénératrices des arbres non-ambigus, desquelles nous déduisons des formulesd’énumérations. Puis, nous interprétons bijectivement certains de ces résultats.Enfin, nous généralisons les arbres non-ambigus à toutes les dimensions finies.Dans la dernière partie, nous construisons une structure arborescente surles polyominos parallélogrammes périodiques, inspirée des travaux de Boussicault,Rinaldi et Socci. Cela nous permet de calculer facilement leur sériegénératrice selon la hauteur et la largeur ainsi que deux nouvelles statistiques :la largeur intrinsèque et la hauteur de recollement intrinsèque. Enfin, nousétudions l’ultime périodicité de leur série génératrice selon l’aireThis thesis deals with a combinatorial interpretation of the stationnarydistribution of the ASEP given by staircase tableaux and studiestwo combinatorial objects : non-ambiguous trees and periodic parallelogrampolyominoes.In the first part, we study the matrix ansatz introduced by Derrida, Evans,Hakim and Pasquier. Any solution of this equation system can be used tocompute the stationnary probabilities of the ASEP. Our work defines newrecurrences equivalent to the matrix ansatz. By defining an insertion algorithmfor staircase tableaux, we prove combinatorially and easily that they satisfyour new recurrences. We do the same for the ASEP with two types of particles.Finally, we enumerate the corners of the tableaux related to the ASEP, whichgives the average number of transitions from a state of the ASEP.In the second part, we compute nice formulas for the generating functionsof non-ambiguous trees, from which we deduce enumeration formulas. Then, wegive a combinatorial interpretation of some of our results. Lastly, we generalisenon-ambiguous trees to every finite dimension.In the last part, we define a tree structure in periodic parallelogram polyominoes,motivated by the work of Boussicault, Rinaldi and Socci. It allowsus to compute easily the generating function with respect to the height andthe width as well as two new statistics : the intrinsic width and the intrinsicgluing height. Finally, we investigate the ultimate periodicity of the generatingfunction with respect to the area
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Li, Chen. "Ultrafast laser-induced nanostructuring of metals in regular patterns." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSES019/document.
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Les structures périodiques de surface induites par laser femtoseconde(fs-LIPSS) attirent l'attention scientifique et technique en raison de la possibilité de produire des nanostructures en dessous de la longueur d'onde optique. Ces éléments sont essentiels pour l'ingénierie de surface et les procédés, notamment en tribologie, mouillabilité, la mécanique, le marquage et la lutte contre la contrefaçon. Selon le régime d'interaction laser, en particulier la fluence du laser, le nombre d'impulsions et le type de matériaux, les impulsions ultracourtes peuvent induire des basses et des hautes fréquences spatiales-LIPSS (LSFL et HSFL), avec l'orientation perpendiculaire (┴E) ou parallèle (║E) à la polarisation du laser. Compte tenu de leur potentiel pour la nano-fabrication, ce travail se concentre sur les mécanismes potentiels de formation des LIPSS, en particulier la formation des HSFL sur les alliages métalliques. Afin d'étudier les indices optiques transitoires de matériaux excités dans la formation fs-LIPSS, nous avons d'abord développé de l’ellipsométrie résolue en temps afin de mesurer les indices optiques dynamiques des matériaux excités. Ainsi, nous avons obtenu un aperçu de la dynamique de la fonction diélectrique intrinsèquement liée à la configuration électronique et au réseau cristallin. Des simulations de premiers principes sont ensuite utilisées pour révéler la façon dont la configuration électronique change au cours de l'excitation, responsable d’indices optiques transitoires. Les effets des indices optiques transitoires sont pris en compte dans les mécanismes de formation de LIPSS. Sur la base d’expériences de formations des fs-LIPSS sur six matériaux différents, incluant du tungstène métallique, du silicium semiconducteur, de la silice fondue diélectrique, un superalliage monocristallin CMSX-4, un alliage amorphe de Zr-BMG et son alliage cristallin correspondant Zr-CA, nous étudions les mécanismes de formation des LIPSS dans le domaine électromagnétique par des simulations de différences finies dans le domaine temporel (FDTD), liées à la distribution d'énergie électromagnétique suivie par la dynamique de l'excitation optique et par l'évolution de la topologie avec le nombre d’impulsions et les matériaux. Nous nous concentrons sur l'origine électromagnétique de la formation des LIPSS et révélons un facteur principal potentiel de leur formation. Elle peut être expliquée par la modulation de l'énergie déposée sur la surface par des effets électromagnétiques. La modulation de l'énergie provient principalement de l'interférence entre le laser incident et les ondes de surface diffusées (pour LSFL ( ┴ E)), complétée par l'interférence entre les ondes de surface diffusées (pour HSFL (┴E)). Spécialement, pour HSFL (║E) sur Zr-CA, nous avons proposé que les scénarios de formation reposent sur des processus individuels d’exaltation anisotrope du champ. La topologie de surface, évoluant avec le nombre d'impulsions laser, induit une modulation d'énergie déposée sur la surface définie et amplifiée par la rétroactionFemtosecond laser-induced periodic surface structures (fs-LIPSS) attract the scientific and technical attention due to the ability to produce nanostructures below the optical wavelength. These are essential for surface engineering and treatment, notably in tribology, wettability, mechanics, marking and counterfeiting. Depending on the regime of laser interaction, particularly on the laser fluence, pulse number and material type, ultrashort pulses can induce the low- and high-spatial-frequency-LIPPS (LSFL and HSFL), with the orientation perpendicular (┴E) or parallel (║E) to the laser polarization. Considering their potential in the nano-manufacturing, this work focuses on potential mechanisms for LIPSS formation, especially HSFL formation on the metallic alloys. In order to investigate the transient optical indices of excited materials in fs-LIPSS formation, we first developed time-resolved ellipsometry to measure dynamic optical indices of excited materials. Thus we gain insights in the dynamics of the dielectric function where this is intrinsically related to the electronic configuration and lattice structure. First principle simulations are then used to reveal how the electronic configuration changes during the excitation, responsible for the transient optical indices. The effects of transient optical indices are considered in the LIPSS formation mechanisms. Based on the experiments of fs-LIPSS formations on six different materials, involving metal tungsten, semiconductor silicon, dielectric fused silica, single-crystal superalloy CMSX-4, amorphous alloy Zr-BMG and its corresponding crystal alloy Zr-CA, we investigate the LIPSS formation mechanisms in the electromagnetic domain by finite-difference time-domain (FDTD) simulations, related to the electromagnetic energy distribution followed by the dynamics of optical excitation, evolving topologies with pulse number and materials.We focus on the electromagnetic origin of LIPSS formation and reveal a potential primary factor for LIPSS formation. LIPSS formation can be explained by deposited energy modulation on surface via electromagnetic effects. The energy modulation mainly comes from the interference between incident laser and scattered surface wave (for LSFL(┴E)), being complemented by the interference between scattered surface waves (for HSFL(┴E)). Specially, for HSFL (║E) on Zr-CA, we proposed that the formation scenarios rely on individual anisotropic field-enhancement processes. The evolving surface topology with laser pulse number leads to a feedback-driven energy modulation deposited on surface