Dissertations / Theses: 'Interpolator'

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Bajramovic, Jasko. "FPGA Implementation of an Interpolator for PWM applications." Thesis, Linköping University, Department of Electrical Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-10406.

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In this thesis, a multirate realization of an interpolation operation is explored. As one of the requirements for proper functionality of the digital pulse-width modulator, a 16-bit digital input signal is to be upsampled 32 times. To obtain the required oversampling ratio, five separate interpolator stages were designed and implemented. Each interpolator stage performed uppsampling by a factor of two followed by an image-rejection lowpass FIR filter. Since, each individual interpolator stage upsamples the input signal by a factor of two, interpolation filters were realized as a half-band FIR filters. This kind of linear-phase FIR filters have a nice property of having every other filter coefficient equal to zero except for the middle one which equals 0.5. By utilizing the half-band FIR filters for the actual realization of the interpolation filters, the overall computational complexity was substantially reduced. In addition, several multirate techniques have been utilized for deriving more efficient interpolator structures. Hence, the impulse response of individual interpolator filters was rewritten into its corresponding polyphase form. This further simplifies the interpolator realization. To eliminate multiplication by 0.5 in one of two polyphase subfilters, the filter gain was deliberately increased by a factor of two. Thus, one polyphase path only contained delay elements. In addition, for the realization of filter multipliers, a multiple constant multiplication, (MCM), algorithm was utilized. The idea behind the MCM algorithm, was to perform multiplication operations as a number of addition operations and appropriate input signal shifts. As a result, less hardware was needed for the actual interpolation chain implementation. For the correct functionality of the interpolator chain, scaling coefficients were introduced into the each interpolation stage. This is done in order to reduce the possibility of overflow. For the scaling process, a safe scaling method was used. The actual quantization noise generated by the interpolator chain was also estimated and appropriate system adjustments were performed.

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Smith, Anthony Paul. "Improved axis synchronisation in a distributed machine control interpolator." Thesis, Nottingham Trent University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261374.

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Lu, Yao. "Development and implementation of parametric interpolator in motion control systems /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?ECED%202007%20LUY.

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Cheng, Ching-Chung. "Investigations into Green's function as inversion-free solution of the Kriging equation, with Geodetic applications." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1095792962.

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Thesis (Ph. D.)--Ohio State University, 2004.
Title from first page of PDF file. Document formatted into pages; contains ix, 125 p.; also includes graphics (some col.). Includes bibliographical references (p. 101-103).

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Liang, Hong. "Minimum error tool path generation method and an interpolator design technique for ultra-precision multiaxis CNC machining." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0021/NQ43585.pdf.

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Namachivayam, Abishek. "High speed Clock and Data Recovery Analysis." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587583678200267.

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Matoušek, Vojtěch. "Návrh a řízení CNC stroje." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-218945.

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My task was to build a smaller structure triaxial CNC milling. I designed electronics for motion control. The main part is the implementation of the control unit, which will provide control of the machine. The work includes the complete design, PCB design and program description for the uP ARM. The unit can work independently as well as hardware interpolator connected to the PC.

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Sievert, Sebastian [Verfasser], Helmut [Akademischer Betreuer] Gräb, Robert [Gutachter] Weigel, and Helmut [Gutachter] Gräb. "Development of Analytical Behavioral Models for Digitally Controlled Edge Interpolator (DCEI) based Digital-to-Time Converter (DTC) Circuits / Sebastian Sievert ; Gutachter: Robert Weigel, Helmut Gräb ; Betreuer: Helmut Gräb." München : Universitätsbibliothek der TU München, 2017. http://d-nb.info/1192441753/34.

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VenkataVikram, Dabbugottu. "FPGA Implementation of Flexible Interpolators and Decimators." Thesis, Linköpings universitet, Elektroniksystem, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-89761.

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The aim of this thesis is to implement flexible interpolators and decimators onField Programmable Gate Array (FPGA). Interpolators and decimators of differentwordlengths (WL) are implemented in VHDL. The Farrow structure is usedfor the realization of the polyphase components of the interpolation/decimationfilters. A fixed set of subfilters and adjustable fractional-delay multiplier valuesof the Farrow structure give different linear-phase finite-length impulse response(FIR) lowpass filters. An FIR filter is designed in such a way that it can be implementedfor different wordlengths (8-bit, 12-bit, 16-bit). Fixed-point representationis used for representing the fractional-delay multiplier values in the Farrow structure. To perform the fixed-point operations in VHDL, a package called fixed pointpackage [1] is used. A 8-bit, 12-bit, and 16-bit interpolator are implemented and their performancesare verified. The designs are compiled in Quartus-II CAD tool for timing analysisand for logical registers usage. The designs are synthesised by selecting Cyclone IVGX family and EP4X30CF23C6 device. The wordlength issues while implementingthe interpolators and decimators are discussed. Truncation of bits is required inorder to reduce the output wordlength of the interpolator and decimator.

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Suarez, Carlos Alberto Galeano. "Otimização da produção de etanol 2G a partir de hexoses e pentoses." Universidade Federal de São Carlos, 2014. https://repositorio.ufscar.br/handle/ufscar/3950.

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Made available in DSpace on 2016-06-02T19:55:39Z (GMT). No. of bitstreams: 1 5990.pdf: 3991723 bytes, checksum: 8f7428459353354f21c1db08bd391507 (MD5) Previous issue date: 2014-02-27
Universidade Federal de Sao Carlos
The industrial production of fuel ethanol and sugar generates the main byproduct of sugarcane bagasse, which is burned in boilers for power generation. However, as a lignocellulosic material (consisting basically of three polymers: cellulose, hemicellulose and lignin), bagasse can be reused for the production of second generation bioethanol (2G), which is a renewable and environmentally friendly biofuel. For industrial 2G bioethanol production becomes economically feasible, the use of all fermentable fractions present in the bagasse is required: C6 fraction (cellulose) and C5 fraction (hemicellulose). These fractions are subjected to hydrolysis processes that generate as main sugars glucose and xylose respectively. It is important, therefore, that the microorganism employed for the production of ethanol 2G is able to utilize all the sugars generated during the hydrolysis process. In this work we chose the yeast Saccharomyces cerevisiae to be the main microorganism used in the industrial production of ethanol, although unfortunately, this yeast is unable to ferment xylose. However, while S. cerevisiae does not use xylose, can ferment xylulose obtained by isomerization of xylose by the enzyme glucose isomerase. The objective of this study was to develop and evaluate technological alternatives for the production of ethanol 2G from hexoses and pentoses using wild S. cerevisiae. In relation to the C6 fraction, in this work two important aspects have been addressed: i) study of the operation regime of a fed-batch reactor enzymatic hydrolysis of the C6 fraction of bagasse from sugarcane, yielding values of final glucose concentration of 200 g.L-1, higher than 45 g.L-1 achieved in batch reactor; ii) kinetic modeling of complex systems (enzymatic hydrolysis of lignocellulosic substrates), in which an interpolator was developed using fuzzy logic as an important tool to represent the processes of enzymatic hydrolysis of lignocellulosic materials for rugged and reliable manner. Now, in relation to the C5 fraction initially applied simple techniques of Evolutionary Engineering, leading to the selection of a different strain of S. cerevisiae, adapted to assimilate xylulose in minimal medium and characterized by reduced formation of xylitol, which demonstrated a selectivity of ~7 getanol.gxilitol -1, significantly higher than the selectivity achieved by the wild strain of ~2 getanol.gxilitol -1. The selected strain was studied in batch cultures conducted in bench scale reactor under different conditions of oxygen limitation. It was found that the production of ethanol is favored over the formation of xylitol, keeping the flow of consumed xylulose above 0,5 mmol.gMS -1.h-1 for flow of oxygen consumption of 0.1 mmol.gMS -1.h-1, reaching in this condition selectivities around 4 getanol.gxilitol -1. For zero flow of oxygen (anaerobic culture) or above 0,3 mmol.gMS -1.h-1, ethanol production is drastically reduced , regardless of the flow xylulose assimilated by the cells.
A produção industrial de etanol combustível e de açúcar gera como principal subproduto o bagaço de cana de açúcar, que é queimado nas caldeiras para geração de energia. Entretanto, por ser um material lignocelulósico (constituído basicamente por três polímeros: celulose, hemicelulose e lignina), o bagaço pode ser reaproveitado para a produção de bioetanol de segunda geração (2G), que é um biocombustível renovável e ambientalmente amigável. Para que a produção industrial de etanol 2G se torne economicamente viável, é necessário o aproveitamento de todas as frações fermentescíveis presentes no bagaço de cana: fração C6 (celulose) e fração C5 (hemicelulose). Estas frações são submetidas a processos de hidrólise que geram como principais açúcares glicose e xilose respetivamente. É importante, portanto, que o microrganismo empregado para a produção de etanol 2G seja capaz de utilizar todos os açúcares gerados no processo de hidrólise. Neste trabalho foi escolhida a levedura Saccharomyces cerevisiae por ser o principal microrganismo utilizado na produção industrial de álcool combustível, embora, infelizmente, esta levedura seja incapaz de fermentar xilose. No entanto, embora S. cerevisiae não utilize xilose, pode fermentar a xilulose obtida pela isomerização de xilose pela enzima xilose isomerase conhecida industrialmente como glicose isomerase. Assim, o objetivo do presente trabalho foi desenvolver e avaliar alternativas tecnológicas para a produção de etanol 2G a partir de hexoses e pentoses, utilizando S. cerevisiae selvagem. Em relação à Fração C6, neste trabalho foram abordados dois aspectos importantes: i) estudo da operação em regime de batelada alimentada de um reator de hidrólise enzimática da fração C6 do bagaço de cana de açúcar, obtendo-se valores de concentração final de glicose de cerca de 200 g.L-1, superiores aos 45 g.L-1 alcançados em reator operado em bateladas simples; ii) modelagem cinética de sistemas complexos (hidrólise enzimática de substratos lignocelulósicos), no qual foi desenvolvido um interpolador utilizando a lógica fuzzy como uma ferramenta importante para representar os processos de hidrólise enzimática de materiais lignocelulósicos de forma robusta e confiável. Já em relação à Fração C5, inicialmente aplicou-se técnicas simples de Engenharia Evolutiva, levando à seleção de uma linhagem diferenciada de S. cerevisiae, adaptada à assimilação de xilulose em meio mínimo e caracterizada por reduzida formação de xilitol, a qual apresentou uma seletividade de ~7 getanol.gxilitol -1, valor significativamente superior à seletividade alcançada pela linhagem selvagem, de ~2 getanol.gxilitol -1. A linhagem selecionada foi então estudada em cultivos em batelada conduzidos em biorreator de bancada, sob diferentes condições de limitação por oxigênio. Verificou-se que a produção de etanol é favorecida, em detrimento da formação de xilitol, mantendo-se o fluxo de xilulose consumida acima de 0,5 mmol.gMS -1.h-1, para fluxo de oxigênio consumido de 0,1 mmol.gMS -1.h-1, alcançando-se nessa condição seletividades em torno de 4 getanol.gxilitol -1. Para fluxos de oxigênio nulo (cultivo anaeróbio) ou acima de 0,3 mmol.gMS -1.h-1, a produção de etanol é drasticamente reduzida, independentemente do fluxo de xilulose assimilado pelas células.

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Lima, Diana Carla de Oliveira Santana. "Análise espacial de populações naturais de Dipteryx alata Vogel. : Subsídio para coleta de sementes /." Ilha Solteira, 2016. http://hdl.handle.net/11449/144503.

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Orientador: Mario Luiz Teixeira de Moraes
Resumo: The spatial distribution pattern of tree species is one of the most important factors for the understanding of the ecological interrelationships occurring in a population or community forestry, it is vital to the understanding of how a certain species uses the resources available to establish and reproduce in a given space. Interpretation of the results of the spatial analysis of tree species provides significant subsidies for the understanding of these phenomena and indication of individuals for genetic conservation programs and forest promotion. In this context, the objective of the work was to study the spatial distribution of six natural populations of arborea specie baru (Dipteryx alata Vogel.) using the Moran index associated with a Geographic Information System and descriptive statistics of their silvicultural attributes. These populations are located in the municipalities of Paulo de Faria/SP, Campina Verde/MG, Ituiutaba/MG, Brasilândia/MS, Campo Grande/MS e Itarumã/GO. All populations had a growth over 45 cm in relation to the DAP (Diameter at Breast Height) attribute. Taking into account that the DAP attribute has a higher dendrochronological correlation, the estimated age of these natural populations would be in the range between 40 and 63 years. As regards the calculation of Moran index, populations of Ituiutaba and Itarumã presented random spatial distribution pattern, pointing high variability among its individuals, so the collection of seeds for ex situ conserv... (Resumo completo, clicar acesso eletrônico abaixo)
Mestre

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Puidokas, Vytenis. "Design and Research on Sigma-Delta Digital-to-Analog Converters for Audio Power Amplifiers." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20111220_133108-90590.

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The dissertation investigates the issues of analyzing a digital Sigma-Delta digital-to-analog converter (DAC) for audio power amplifiers. The main objects of research include a digital Sigma-Delta audio power DAC, improvement of its structure and an experimental research. The primary purpose of the dissertation is to suggest methods for improvement the structure of digital Sigma-Delta audio power DAC interpolator and the converter analysis.
Disertacijoje nagrinėjami Sigma-Delta skaitmeniniai-analoginiai (skaičiaus-analogo, SA) keitikliai garso galios stiprintuvams. Pagrindinis tyrimų objektas – skaitmeninis Sigma-Delta garso galios SA keitiklis, jo sandaros tobulinamas bei eksperimentinis tyrimas. Disertacijos tikslas – pasiūlyti skaitmeninio Sigma-Delta garso galios SA keitiklio interpoliatoriaus struktūros tobulinimo bei keitiklio tyrimo metodus.

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Jung, Seok Min, and Seok Min Jung. "Design and Implementation of Low Jitter Clock Generators in Communication and Aerospace System." Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/621292.

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The high demands on data processing and bandwidth in wireless/wireline communication and aerospace systems have been pushing forward circuit design techniques to their limitations to obtain maximum performances with respect to high operating frequency, low noise, small area, and low power consumption. Clock generators are essential components in numerous circuits, for instance, frequency synthesizers for high speed transceivers, clock sources for microprocessors, noise suppressed zero-delay buffers in system-on-chips (SOCs), and clock and data recovery (CDR) systems. Furthermore, clock generators are required to provide low jitter and high precision clocks in fully integrated image reject receivers and an ultra-wide tunability in time-interleaved applications. We explore several circuit design techniques and implementations of low jitter clock generator in this thesis. Firstly, a low jitter and wide range digital phase-locked loop (DPLL) operating 8 ~ 16 GHz is illustrated using a dual path digital loop filter (DLF). In order to mitigate the phase jitter in the phase detector (PD), we implement the separate loop filter and the output is not affected by the proportional path. For the stable operation, a 4 ~ 8 GHz linear phase interpolator (PI) is implemented in the proportional path. In addition, we design a low phase noise digitally controlled oscillator (DCO) using inductive tuning technique based on switched mutual coupling for wide operating range. The proposed DPLL implemented in 65 nm CMOS technology shows an outstanding figure-of-merit (FOM) over other state-of-art DPLLs in term of root mean square (RMS) and deterministic jitter (DJ). Secondly, we discuss a radiation-hardened-by-design (RHBD) PLL using a feedback voltage-controlled oscillator (FBVCO) in order to reduce DJ due to the radiation attack on the control voltage. Different from a conventional open loop VCO, the proposed FBVCO has a negative control loop and is composed of an open loop VCO, an integrator and a switched-capacitor resistor. Since the input to output of the FBVCO has a low-pass characteristic, any disturbance on the control voltage should be filtered and cannot affect the output phase. We are able to reduce the output frequency variation approximately 75% compared to the conventional PLL when the radiation pulse strikes on the control voltage. The proposed RHBD PLL is implemented in 130 nm and consumes 6.2 mW at 400 MHz operating frequency. Thirdly, a novel adaptive-bandwidth PLL is illustrated to optimize the jitter performance in a wide operating frequency range. We achieve a constant ratio of bandwidth and reference frequency with a closed loop VCO and an overdamping system with a charge pump (CP) current proportional to the VCO frequency for the adaptive-bandwidth technique. The proposed adaptive-bandwidth PLL presents 0.6% RMS jitter over the entire frequency range from 320 MHz to 2.56 GHz, which is 70% smaller than the conventional fixed-bandwidth PLL. Finally, we have developed a new feedback DCO to achieve a linear gain of DCO so that the DPLL can provide stability and a wide operating range in different process variations. Due to the negative feedback loop of the proposed DCO, the feedback DCO presents a linear gain from an input digital word to an output frequency. Moreover, we can control the bandwidth of the feedback DCO to optimize the total output phase noise in DPLL. In simulation, we can obtain 17 MHz/LSB of the peak-to-peak gain of the feedback DCO, which is reduced 96% over the conventional DCO.

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Van, der Walt Maria Dorothea. "Ternary interpolatory subdivision." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71652.

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Thesis (MSc)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: Subdivision is an important and e cient tool for rendering smooth curves and surfaces in computer graphics, by repeatedly applying a subdivision (re ning) scheme to a given set of points. In the literature, attention has been mostly restricted to developing binary subdivision schemes. The primary emphasis of this thesis is on ternary subdivision, and in particular on the interpolatory case. We will derive a symmetric ternary interpolatory subdivision scheme for the rendering of curves, satisfying analogous properties to the Dubuc-Deslauriers binary scheme. Explicit construction methods, as well as a corresponding convergence analysis, will be presented. Graphical illustrations of the results will also be provided.
AFRIKAANSE OPSOMMING: Subdivisie bied 'n belangrike en doeltre ende metode om gladde krommes en oppervlakke in rekenaargra ka te genereer. Hierdie metode behels dat 'n subdivisieskema (of verfyningskema) herhaaldelik toegepas word op 'n gegewe versameling punte. In die literatuur word daar hoofsaaklik gefokus op die ont- wikkeling van bin^ere subdivisieskemas. In hierdie tesis word die klem gel^e op tern^ere subdivisieskemas, en in die besonder op interpolerende skemas. Ons sal 'n simmetriese tern^ere interpolerende subdivisieskema, wat analo e eienskappe as di e van die Dubuc-Deslauriers bin^ere skema bevredig, ontwikkel, om krom- mes te lewer. Eksplisiete konstruksiemetodes en ooreenkomstige konvergensie- analise, asook gra ese illustrasies van die resultate, sal getoon word.

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Camurani, Andrea. "Metodi di calibrazione e sistema di misura di Timing Mismatch per un convertitore RFDAC realizzato con architettura a current steering in tecnologia FinFET." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20229/.

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Il presente lavoro di tesi, svolto presso Xilinx in Irlanda, è focalizzato alla calibrazione e misura delle non idealità dinamiche presenti nei convertitori digitali-analogici (Digital to Time Converter) a radio frequenza, con architettura a Current-Steering. Questa architettura, controllata da una logica combinata di bit termometrici (6 MSB) e bit binari (10 LSB), permette di avere alte prestazioni di velocità. Le non idealità consistono nel disallineamento temporale di questi bit, che aumentano tanto più la frequenza del dato in ingresso aumenta. La necessità di metodi di calibrazione per questi effetti è necessaria al fine di ottenere delle prestazioni del convertitore accettabili per il mercato. In questa tesi viene quindi data una visione riguardante la calibrazione di questi errori temporali, forniti da un modello scritto in Verilog A, di un convertitore RFDAC a 16 bit operante con una frequenza di clock di 6.4GHz. In realtà, su silicio, questi errori temporali devono essere misurati con precisione da un sistema di misura. Si è contribuito al progetto e alla caratterizzazione, utilizzando librerie FinFET TSMC (Taiwan Semiconductor Manufacturing Company) in Cadence Virtuoso, di un sistema di misura integrato che consente di misurare il disallineamento temporale di questi bit, con una precisione di 150fs.

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Rabut, Christophe. "B-splines polyharmoniques cardinales : interpolation, quasi-interpolation, filtrage." Toulouse 3, 1990. http://www.theses.fr/1990TOU30046.

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Les B-splines polynomiales sont couramment utilisées pour définir simplement une fonction spline qui passe "près" de points donnés. Dans le cas où les données sont régulièrement réparties, on apporte, par un traitement préalable des données (convolution avec certains vecteurs à support borné), plus de souplesse à cette opération : on peut alors obtenir une fonction qui passe très près des points -on parle alors de quasi-interpolation- ou au contraire qui filtre les bruits inhérents à ces données on parle alors de filtrage. On montre comment utiliser la méthode de validation croisée pour choisir de façon optimale la force d'un filtrage, qui peut être adaptative, et on propose une méthode de réduction de données, le taux de réduction étant lié à la bande passante du filtre. Ces notions sont ensuite généralisées en dimension quelconque par l'utilisation des B-splines polyharmoniques : après avoir defini les splines polyharmoniques pour des données qui peuvent être en nombre infini, on en donne une expression numériquement plus stable que celle généralement utilisée, et on montre un lien entre splines polyharmoniques d'ordre ou de dimension différents. On définit alors les B-splines polyharmoniques, et on présente leurs propriétés essentielles, très voisines de celles des B-splines polynomiales. On propose l'utilisation de ces B-splines d'une part pour quasi-interpoler ou filtrer des données régulièrement réparties, d'autre part pour déterminer rapidement, par une méthode de subdivision, la spline d'interpolation de ces données. On envisage enfin la généralisation de cette notion de B-spline à des noeuds quelconques et à toute famille de fonctions satisfaisant certaines équations différentielles.

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Ramesh, Gayatri. "FRACTAL INTERPOLATION." Master's thesis, University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3128.

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This thesis is devoted to a study about Fractals and Fractal Polynomial Interpolation. Fractal Interpolation is a great topic with many interesting applications, some of which are used in everyday lives such as television, camera, and radio. The thesis is comprised of eight chapters. Chapter one contains a brief introduction and a historical account of fractals. Chapter two is about polynomial interpolation processes such as Newton s, Hermite, and Lagrange. Chapter three focuses on iterated function systems. In this chapter I report results contained in Barnsley s paper, Fractal Functions and Interpolation. I also mention results on iterated function system for fractal polynomial interpolation. Chapters four and five cover fractal polynomial interpolation and fractal interpolation of functions studied by Navascués. Chapter five and six are the generalization of Hermite and Lagrange functions using fractal interpolation. As a concluding chapter we look at the current applications of fractals in various walks of life such as physics and finance and its prospects for the future.
M.S.
Department of Mathematics
Sciences
Mathematical Science MS

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Penot, David. "Cartographie des événements hydrologiques extrêmes et estimation SCHADEX en sites non jaugés." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENU022/document.

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Depuis 2006, à EDF, les études de crues extrêmes sont réalisées avec la méthode SCHADEX (Simulation Climato-Hydrologique pour l'Appréciation des Débits EXtrêmes). Elle s'appuie sur un modèle probabiliste MEWP (distribution saisonnière utilisant une classification par type de temps) pour décrire l'aléa pluie et sur une simulation stochastique croisant l'aléa pluie et l'aléa de saturation du bassin. Les approches par simulation, type SCHADEX, ont montré de bonnes performances pour estimer les distributions de crues extrêmes (projet ANR ExtraFlo , 2013). Cependant, l'utilisation de SCHADEX en l'absence de données (pluie, température, débit) sur le bassin à étudier reste problématique. Cette thèse propose une adaptation de la méthode en site non jaugé en essayant de conserver ses points forts, à savoir: - une structuration spatiale et probabiliste des précipitations conditionnée par les types de temps. - un croisement des aléas pluie et saturation du bassin par simulation stochastique. Ce travail s'est limité au pas de temps journalier afin d'aborder la problématique de régionalisation avec un maximum de données. La démarche s'est alors articulée autour de quatre grands axes: - proposer une méthode de régionalisation des précipitations journalières extrêmes ponctuelles et construire des cartes de pluies aux temps de retour remarquables. Évaluer l'intérêt d'une classification par type de temps pour la régionalisation des distributions de pluies extrêmes et qualifier l'interpolateur de pluie SPAZM pour l'estimation des pluies extrêmes. - s'intéresser à la construction de pluies de bassin (ou pluies spatiales) et en particulier à l'impact des choix de construction de cette pluie sur l'estimation des précipitations extrêmes concernant le bassin. - développer une méthode de simulation stochastique régionale permettant de proposer une distribution de débits journaliers issue d'un croisement des aléas pluies et saturation du bassin. - étudier le passage de la distribution des débits journaliers à la distribution des débits de pointe. Les principaux apports de cette thèse sont les suivants: - la prise en compte des types de temps permet d'améliorer la description des structures spatiales des précipitations extrêmes. - l'information apportée par les pluies SPAZM se révèle être précieuse pour l'estimation des pluies extrêmes en site non jaugé. - une étude de sensibilité du calcul de la pluie spatiale en fonction du nombre de postes utilisés (comparaison des pluies SPAZM et Thiessen) donne une indication sur le biais d'estimation. - le générateur de champs de pluie par bandes tournantes SAMPO permet d'étudier l'abattement sur les précipitations extrêmes et de mettre en place un modèle de correction pour les quantiles élevés des pluies spatiales SPAZM. - une nouvelle méthode de simulation stochastique peu paramétrée mais analogue à la méthode SCHADEX (croisement d'un aléa pluie et d'un aléa de saturation du bassin pour produire une distribution des débits journaliers) est proposée pour l'estimation en site non jaugé. - enfin, un travail préliminaire donne des premiers éléments sur le passage à la distribution des débits de pointe par un générateur d'hydrogrammes s'adaptant à la séquence des débits journaliers simulés. Tous ces développements et conclusions sont détaillés et justifiés dans le mémoire de thèse
Since 2006, at EDF, extreme flood estimations are computed with the SCHADEX method (Climatic-hydrological simulation of extreme floods). This method relies on a MEWP probabilistic model (seasonal rainfall distribution using a weather pattern concept) and on a stochastic simulation to cross rainy events hazard and catchment saturation states. Simulation approaches, as SCHADEX, have shown good performances to estimate extreme flood distributions. However, the use of SCHADEX method without data for a considered catchment (rain, temperature, runoff) remains a main issue. This thesis suggests an adaptation of the method in ungauged context, trying to keep the key points of the SCHADEX method: - spatial and probabilistic structure of rainfall conditioned by weather patterns. - a cross of rainfall and catchment saturation hazards by stochastic simulation. This work is limited to a daily step to address the issue of regionalization with a maximum of data. The approach is then structured around four main points: - regionalize punctual daily extreme precipitations and construct maps of return period rainfalls. Evaluate the contribution of a weather type classification for the regionalization of extreme rainfall distributions and qualify the SPAZM interpolator for the estimation of extreme rainfall. - wonder about the construction of an areal rainfall and in particular about the impact of its construction choices on the estimation of extreme precipitations. - develop a regional stochastic simulation method to estimate a distribution of daily runoffs which crosses rainy events and catchment saturation hazards. - study the transposition from a daily runoff distribution to a peak flow distribution. The main contributions of this thesis are: - taking into account the weather types improves the description of spatial patterns of extreme precipitations. - information provided by the SPAZM rainfall interpolator proves to be valuable for the estimation of extreme rainfall in ungauged site. - a sensitivity analysis of the calculation of the areal rainfall based on the number of stations used (comparison SPAZM and Thiessen areal rainfalls) gives an indication of the estimation bias. - the SAMPO rainfall generator used to study the areal reduction factor of extreme precipitation and implement a correction model for high quantiles of SPAZM areal rainfall. - a simplified method of stochastic simulation similar to SCHADEX method (cross between a rainfall hazard and a catchment saturation hazard) is developed to produce a distribution of daily flows in ungauged site. - finally, preliminary work provides a way for the transition to the peak flow distribution using a hydrograph generator adapted to the sequence of daily simulated runoffs. All these developments and conclusions are detailed and justified in the thesis.STAR

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Christ, Jürgen [Verfasser], and Andreas [Akademischer Betreuer] Podelski. "Interpolation modulo theories." Freiburg : Universität, 2015. http://d-nb.info/1119805767/34.

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Goggins, Dan. "Constraint-based interpolation /." Diss., CLICK HERE for online access, 2005. http://contentdm.lib.byu.edu/ETD/image/etd976.pdf.

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Yeung, R. Kacheong. "Stable rational interpolation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0021/NQ46952.pdf.

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Winebarger, Onnie Lynn. "k-Interpolated sequences." [Bloomington, Ind.] : Indiana University, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3229597.

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Thesis (Ph.D.)--Indiana University, Dept. of Mathematics, 2006.
"Title from dissertation home page (viewed July 11, 2007)." Source: Dissertation Abstracts International, Volume: 67-08, Section: B, page: 4466. Adviser: Daniel P. Maki.

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Merrell, Jacob Porter. "Generalized Constrained Interpolation." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2360.pdf.

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Goggins, Daniel David. "Constraint-Based Interpolation." BYU ScholarsArchive, 2005. https://scholarsarchive.byu.edu/etd/610.

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Image reconstruction is the process of converting a sampled image into a continuous one prior to transformation and resampling. This reconstruction can be more accurate if two things are known: the process by which the sampled image was obtained and the general characteristics of the original image. We present a new reconstruction algorithm known as Constraint-Based Interpolation, which estimates the sampling functions found in cameras and analyzes properties of real world images in order to produce quality real-world image magnifications. To accomplish this, Constraint-Based Interpolation uses a sensor model that pushes the pixels in an interpolation to more closely match the data in the sampled image. Real-world image properties are ensured with a level-set smoothing model that smooths "jaggies" and a sharpening model that alleviates blurring. This thesis describes the three models, their methods and constraints. The effects of the various models and constraints are also shown, as well as a human observer test. A variation of a previous interpolation technique, Quad-based Interpolation, and a new metric, gradient weighted contour curvature, is presented and analyzed.

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Fang, Quanlei. "Multivariable Interpolation Problems." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/28311.

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In this dissertation, we solve multivariable Nevanlinna-Pick type interpolation problems. Particularly, we consider the left tangential interpolation problems on the commutative or noncommutative unit ball. For the commutative setting, we discuss left-tangential operator-argument interpolation problems for Schur-class multipliers on the Drury-Arveson space and for the noncommutative setting, we discuss interpolation problems for Schur-class multipliers on Fock space. We apply the Krein-space geometry approach (also known as the Grassmannian Approach). To implement this approach J-versions of Beurling-Lax representers for shift-invariant subspaces are required. Here we obtain these J-Beurling-Lax theorems by the state-space method for both settings. We see that the Krein-space geometry method is particularly simple in solving the interpolation problems when the Beurling-Lax representer is bounded. The Potapov approach applies equally well whether the representer is bounded or not.
Ph. D.

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Hunter, Karin M. "Interpolatory refinable functions, subdivision and wavelets." Thesis, Stellenbosch : University of Stellenbosch, 2005. http://hdl.handle.net/10019.1/1156.

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Thesis (DSc (Mathematical Sciences))--University of Stellenbosch, 2005.
Subdivision is an important iterative technique for the efficient generation of curves and surfaces in geometric modelling. The convergence of a subdivision scheme is closely connected to the existence of a corresponding refinable function. In turn, such a refinable function can be used in the multi-resolutional construction method for wavelets, which are applied in many areas of signal analysis.

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Rabarison, Andrianarivo Fabien. "Interpolatory bivariate refinable functions and subdivision." Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/2095.

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Wyatt, Sarah Alice. "Inexact Solves in Interpolatory Model Reduction." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/33042.

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Dynamical systems are mathematical models characterized by a set of differential or difference equations. Due to the increasing demand for more accuracy, the number of equations involved may reach the order of thousands and even millions. With so many equations, it often becomes computationally cumbersome to work with these large-scale dynamical systems. Model reduction aims to replace the original system with a reduced system of significantly smaller dimension which will still describe the important dynamics of the large-scale model. Interpolation is one method used to obtain the reduced order model. This requires that the reduced order model interpolates the full order model at selected interpolation points. Reduced order models are obtained through the Krylov reduction process, which involves solving a sequence of linear systems. The Iterative Rational Krylov Algorithm (IRKA) iterates this Krylov reduction process to obtain an optimal $\mathcal{H}_2$ reduced model. Especially in the large-scale setting, these linear systems often require employing inexact solves. The aim of this thesis is to investigate the impact of inexact solves on interpolatory model reduction.

We considered preconditioning the linear systems, varying the stopping tolerances, employing GMRES and BiCG as the inexact solvers, and using different initial shift selections. For just one step of Krylov reduction, we verified theoretical properties of the interpolation error. Also, we found a linear improvement in the subspace angles between the inexact and exact subspaces provided that a good shift selection was used. For a poor shift selection, these angles often remained of the same order regardless of how accurately the linear systems were solved. These patterns were reflected in $\mathcal{H}_2$ and $\mathcal{H}_{\infty}$ errors between the inexact and exact subspaces, since these errors improved linearly with a good shift selection and were typically of the same order with a poor shift. We found that the shift selection also influenced the overall model reduction error between the full model and inexact model as these error norms were often several orders larger when a poor shift selection was used. For a given shift selection, the overall model reduction error typically remained of the same order for tolerances smaller than $1 \times 10^{-3}$, which suggests that larger tolerances for the inexact solver may be used without necessarily augmenting the model reduction error. With preconditioned linear systems as well as BiCG, we found smaller errors between the inexact and exact models while the order of the overall model reduction error remained the same. With IRKA, we observed similar patterns as with just one step of Krylov reduction. However, we also found additional benefits associated with using an initial guess in the inexact solve and by varying the tolerance of the inexact solve.
Master of Science

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Cheatham, Robert M. "A Geometry-Based Motion Planner for Direct Machining and Control." BYU ScholarsArchive, 2007. https://scholarsarchive.byu.edu/etd/1411.

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Direct Machining And Control (DMAC) is a new method of controlling machine tools directly from process planning software. A motion planning module is developed for the DMAC system that operates directly off path geometry without pre-tessellation. The motion planner is developed with the intent to process Bezier curves. The motion planning module includes a deterministic predictor-corrector-type curve interpolator, a dynamics limiting module, and a two-pass jerk-limited speed profiling algorithm. The methods are verified by machining an automotive surface in a clay medium and evaluating the resultant machine dynamics, feed rate, and chordal error throughout the machining process.

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Ameur, Yacin. "Interpolation of Hilbert spaces." Doctoral thesis, Uppsala universitet, Matematiska institutionen, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-1753.

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(i) We prove that intermediate Banach spaces A, B with respect to arbitrary Hilbert couples H, K are exact interpolation iff they are exact K-monotonic, i.e. the condition f0∊A and the inequality K(t,g0;K)≤K(t,f0;H), t>0 imply g0∊B and ||g0||B≤||f0||A (K is Peetre's K-functional). It is well-known that this property is implied by the following: for each ρ>1 there exists an operator T : H→K such that Tf0=g0, and K(t,Tf;K)≤ρK(t,f;H), f∊H0+H1, t>0.Verifying the latter property, it suffices to consider the "diagonal" case where H=K is finite-dimensional. In this case, we construct the relevant operators by a method which allows us to explicitly calculate them. In the strongest form of the theorem, it is shown that the statement remains valid when substituting ρ=1. (ii) A new proof is given to a theorem of W. F. Donoghue which characterizes certain classes of functions whose domain of definition are finite sets, and which are subject to certain matrix inequalities. The result generalizes the classical Löwner theorem on monotone matrix functions, and also yields some information with respect to the finer study of monotone functions of finite order. (iii) It is shown that with respect to a positive concave function ψ there exists a function h, positive and regular on ℝ+ and admitting of analytic continuation to the upper half-plane and having positive imaginary part there, such that h≤ψ≤ 2h. This fact is closely related to a theorem of Foiaş, Ong and Rosenthal, which states that regardless of the choice of a concave function ψ, and a weight λ, the weighted l2-space l2(ψ(λ)) is c-interpolation with respect to the couple (l2,l2(λ)), where we have c≤√2 for the best c. It turns out that c=√2 is best possible in this theorem; a fact which is implicit in the work of G. Sparr. (iv) We give a new proof and new interpretation (based on the work (ii) above) of Donoghue's interpolation theorem; for an intermediate Hilbert space H* to be exact interpolation with respect to a regular Hilbert couple H it is necessary and sufficient that the norm in H* be representable in the form ||f||*= (∫[0,∞] (1+t-1)K2(t,f;H)2dρ(t))1/2 with some positive Radon measure ρ on the compactified half-line [0,∞]. (v) The theorem of W. F. Donoghue (item (ii) above) is extended to interpolation of tensor products. Our result is related to A. Korányi's work on monotone matrix functions of several variables.

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Kristoffersen, Stian. "The Empirical Interpolation Method." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for matematiske fag, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-23378.

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In this thesis we look at the Empirical Interpolation Method (EIM) and how it can be used in different applications. We propose a new formulation of EIM to make it easier to perform analytical operations like differentiation and integration of the basis functions as well as to apply EIM to a variety of problems. The new formulation is used to develop quadrature rules for the circle and semicircle, as well as for arbitrary simple polygons. The new formulation is also used to solve partial differential equations using a collocation approach on various domains including the circle, semicircle and triangle. The framework is briefly applied to compression of 3D animation in addition to recognition of images and sound.Several of the methods show great potential, with exponential convergence for quadrature and collocation for regular problems. However, there are also serious issues that must be addressed if the methods are to be developed further. These issues are related to making the methods more robust and stable.

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Ameur, Yacin. "Interpolation of Hilbert spaces /." Uppsala : Matematiska institutionen, Univ. [distributör], 2001. http://publications.uu.se/theses/91-506-1531-9/.

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Du, Toit Wilna. "Radial basis function interpolation." Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/2002.

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Thesis (MSc (Applied Mathematics))--Stellenbosch University, 2008.
A popular method for interpolating multidimensional scattered data is using radial basis functions. In this thesis we present the basic theory of radial basis function interpolation and also regard the solvability and stability of the method. Solving the interpolant directly has a high computational cost for large datasets, hence using numerical methods to approximate the interpolant is necessary. We consider some recent numerical algorithms. Software to implement radial basis function interpolation and to display the 3D interpolants obtained, is developed. We present results obtained from using our implementation for radial basis functions on GIS and 3D face data as well as an image warping application.

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Goosen, Karin M. (Karin Michelle). "Subdivision, interpolation and splines." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51924.

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Thesis (MSc)--University of Stellenbosch, 2000.
ENGLISH ABSTRACT: In this thesis we study the underlying mathematical principles of stationary subdivision, which can be regarded as an iterative recursion scheme for the generation of smooth curves and surfaces in computer graphics. An important tool for our work is Fourier analysis, from which we state some standard results, and give the proof of one non-standard result. Next, since cardinal spline functions have strong links with subdivision, we devote a chapter to this subject, proving also that the cardinal B-splines are refinable, and that the corresponding Euler-Frobenius polynomial has a certain zero structure which has important implications in our eventual applications. The concepts of a stationary subdivision scheme and its convergence are then introduced, with as motivating example the de Rahm-Chaikin algorithm. Standard results on convergence and regularity for the case of positive masks are quoted and graphically illustrated. Next, we introduce the concept of interpolatory stationary subdivision, in which case the limit curve contains all the original control points. We prove a certain set of sufficient conditions on the mask for convergence, at the same time also proving the existence and other salient properties of the associated refinable function. Next, we show how the analysis of a certain Bezout identity leads to the characterisation of a class of symmetric masks which satisfy the abovementioned sufficient conditions. Finally, we show that specific special cases of the Bezout identity yield convergent interpolatory symmetric subdivision schemes which are identical to choosing the corresponding mask coefficients equal to certain point evaluations of, respectively, a fundamental Lagrange interpolation polynomial and a fundamental cardinal spline interpolant. The latter procedure, which is known as the Deslauriers-Dubuc subdivision scheme in the case of a polynomial interpolant, has received attention in recent work, and our approach provides a convergence result for such schemes in a more general framework. Throughout the thesis, numerical illustrations of our results are provided by means of graphs.
AFRIKAANSE OPSOMMING: In hierdie tesis ondersoek ons die onderliggende wiskundige beginsels van stasionêre onderverdeling, wat beskou kan word as 'n iteratiewe rekursiewe skema vir die generering van gladde krommes en oppervlakke in rekenaargrafika. 'n Belangrike stuk gereedskap vir ons werk is Fourieranalise, waaruit ons sekere standaardresuJtate formuleer, en die bewys gee van een nie-standaard resultaat. Daarna, aangesien kardinale latfunksies sterk bande het met onderverdeling, wy ons 'n hoofstuk aan hierdie onderwerp, waarin ons ook bewys dat die kardinale B-Iatfunksies verfynbaar is, en dat die ooreenkomstige Euler-Frobenius polinoom 'n sekere nulpuntstruktuur het wat belangrike implikasies het in ons uiteindelike toepassings. Die konsepte van 'n stasionêre onderverdelingskema en die konvergensie daarvan word dan bekendgestel, met as motiverende voorbeeld die de Rahm-Chaikin algoritme. Standaardresultate oor konvergensie en regulariteit vir die geval van positiewe maskers word aangehaal en grafies geïllustreer. Vervolgens stelons die konsep van interpolerende stasionêre onderverdeling bekend, in welke geval die limietkromme al die oorspronklike kontrolepunte bevat. Ons bewys 'n sekere versameling van voldoende voorwaardes op die masker vir konvergensie, en bewys terselfdertyd die bestaan en ander toepaslike eienskappe van die ge-assosieerde verfynbare funksie. Daarna wys ons hoedat die analise van 'n sekere Bezout identiteit lei tot die karakterisering van 'n klas simmetriese maskers wat die bovermelde voldoende voorwaardes bevredig. Laastens wys ons dat spesifieke spesiale gevalle van die Bezout identiteit konvergente interpolerende simmetriese onderverdelingskemas lewer wat identies is daaraan om die ooreenkomstige maskerkoëffisientegelyk aan sekere puntevaluasies van, onderskeidelik, 'n fundamentele Lagrange interpolasiepolinoom en 'n kardinale latfunksie-interpolant te kies. Laasgenoemde prosedure, wat bekend staan as die Deslauriers-Dubuc onderverdelingskema in die geval van 'n polinoominterpolant, het aandag ontvang in onlangse werk, en ons benadering verskaf 'n konvergensieresultaat vir sulke skemas in 'n meer algemene raamwerk. Deurgaans in die tesis word numeriese illustrasies van ons resultate met behulp van grafieke verskaf.

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35

Eastwood, Alan. "Interpolation à plusieurs variables." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37613442b.

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FERREIRA, CARLOS ROBERTO DA COSTA. "MODIFIED INTERPOLATION OF LSFNULLS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2006. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=9195@1.

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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
Os novos serviços de telecomunicações têm impulsionado o desenvolvimento de melhorias nos algoritmos de codificação de voz, devido à necessidade de se melhorar a qualidade da voz codificada, utilizando a menor taxa de transmissão possível. Esta dissertação analisa e propõem melhorias em um método para o ajuste de parâmetros LSFs de modo a torná- los mais precisos, minimizando as perdas no processo de interpolação de LSFs codificadas. Com isso, a percepção de qualidade da voz sintetizada na saída do decodificador é aumentada, sem que seja necessário aumento da taxa de transmissão. É apresentada de modo detalhado toda a dedução matemática do método citado. Para a avaliação de desempenho das melhorias propostas, o processo de ajuste é implementado em um codificador a taxas médias inferiores a 2 kb/s. Os resultados confirmam que é possível obter redução significativa nas medidas de distorção com a utilização do ajuste de LSFs.
The new telecommunications services have been pushing forward the development of improvements in speech coding, because of the need to improve coded speech quality, using the smallest transmission rate possible. This thesis analyzes and proposes improvements in a method to adjust LSF parameters so they get more accurate, minimizing the losses in the coded LSFs interpolation process. With this, the synthesized speech perceptual quality in the decoder exit is increased, without having to increase the transmission rate. The mathematical deduction of the method is presented in a detailed way. To evaluate the performance of the proposed improvements, the adjust process is implemented in a speech coder with mean rates less than 2 kb/s. The results confirmed that is possible to obtain significant reduction in distortion measures using the adjustment of LSFs.

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Jin, Shangzhu. "Backward fuzzy rule interpolation." Thesis, Aberystwyth University, 2015. http://hdl.handle.net/2160/e4e6acbd-914f-4c8a-b40c-91b13a017c69.

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Naik, Nitin. "Dynamic fuzzy rule interpolation." Thesis, Aberystwyth University, 2015. http://hdl.handle.net/2160/1caf8126-23c0-4c9c-9d8d-16c65f2f9878.

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Designers of effective and efficient fuzzy systems have long recognised the value of inferential hybridity in the implementation of sparse fuzzy rule based systems. Which is to say: such systems should have recourse to fuzzy rule interpolation (FRI) only when no rule matches a given observation; otherwise, when an observation partially or exactly matches at least one of the rules of the sparse rule base, a compositional rule of inference (CRI) should be used in order to avoid the computational overheads of interpolation. Sparse fuzzy rule bases are constructed by experts or derived from data and may support FRI reasoning in long run. However, two potential problems arise: (1) a system's requirements may change over time leading to rule redundancy; and (2) the system may cease in the long run to provide precise and pertinent results. The need to maintain the concurrency and accuracy of a sparse fuzzy rule base, in order that it generates the most precise and relevant results possible, motivates consideration of a dynamic (real-time) fuzzy rule base. This thesis therefore presents a framework of dynamic fuzzy rule interpolation (D-FRI), integrated with general fuzzy inference (CRI), which uses the FRI result set itself for the selection, combination and promotion of informative, frequentlyused intermediate rules into the existing rule base. Here two versions of the D-FRI approach are presented:k-means-based and GA-aided. Integration uses the concept of -cut overlapping between fuzzy sets to decide an exact or partial matching between rules and observation so that CRI can be utilised for reasoning. Otherwise, the best closest rules are selected for FRI by exploiting the centre of gravity (COG), Hausdorff distance (HD) and earth mover's distance (EMD) metrics. Testing seeks to show that dynamically-promoted rules generate results of greater accuracy and robustness than would be achievable through conventional FRI tout court, and to support the claim that the D-FRI approach results in a more effective interpolative reasoning system. To this end, an implementation of D-FRI is applied to the problem domain of intrusion detection systems (IDS), by integrating it with Snort in order to improve port-scanning detection and increase the level of accuracy of alert predictions.

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Calvi, Jean-Paul. "Interpolation et fonctionnelles analytiques." Toulouse 3, 1993. http://www.theses.fr/1993TOU30014.

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Nous etudions quelques problemes d'interpolation (essentiellement polynomiale). Dans le chapitre premier, nous etudions la reconstruction d'une fonction de plusieurs variables complexes au moyen de polynomes d'interpolation obtenus par la donnee de certaines fonctionnelles des derivees. Plusieurs methodes classiques d'interpolation se laissent mettre sous la forme etudiee. Le second chapitre traite d'un probleme de convergence du polynome d'interpolation de kergin. Etant donnes trois ensembles compacts e,f,g, nous disons que la propriete (e,f,g) est verifiee lorsque pour chaque tableau d'interpolation dans f, chaque fonction f analytique dans un voisinage de g, le polynome de kergin de f converge uniformement vers f sur e. Etant donnes deux de ces trois ensembles, il s'agit de construire le troisieme de telle sorte que (e,f,g) soit verifiee. Dans le dernier chapitre nous etudions le probleme de l'interpolation sous une forme plus abstraite. Nous donnons une condition necessaire et suffisante pour qu'une suite de formes lineaires continues sur un espace de frechet soit d'interpolation. En particulier nous proposons un critere pratique qui est applique a plusieurs problemes naturels de la theorie classique des fonctions

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Eastwood, Alan. "Interpolation à plusieurs variables." Nice, 1988. http://www.theses.fr/1988NICE4170.

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On caractérise les sous-schémas génériques localement rectilignes de dimension zéro rangés de l'espace projectif de dimension finie quelconque sur un corps algébriquement clos. On en tire quelques corollaires

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Iebesh, Abdulhamid. "Interpolation of Yield curves." Thesis, Mälardalens högskola, Akademin för utbildning, kultur och kommunikation, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-48968.

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In this thesis we survey several interpolation methods that are used to construct the yield curves. We also review the bootstrapping and show that the bootstrap is closely connected to the interpolation in the case of bootstrapping yield curve. The most effort is dedicated, in this thesis, on the monotone convex method and on investigation of the difficulties to get accurate yield curves.

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42

Baur, Ulrike, Christopher Beattie, Peter Benner, and Serkan Gugercin. "Interpolatory Projection Methods for Parameterized Model Reduction." Universitätsbibliothek Chemnitz, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-201000011.

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We provide a unifying projection-based framework for structure-preserving interpolatory model reduction of parameterized linear dynamical systems, i.e., systems having a structured dependence on parameters that we wish to retain in the reduced-order model. The parameter dependence may be linear or nonlinear and is retained in the reduced-order model. Moreover, we are able to give conditions under which the gradient and Hessian of the system response with respect to the system parameters is matched in the reduced-order model. We provide a systematic approach built on established interpolatory $\mathcal{H}_2$ optimal model reduction methods that will produce parameterized reduced-order models having high fidelity throughout a parameter range of interest. For single input/single output systems with parameters in the input/output maps, we provide reduced-order models that are \emph{optimal} with respect to an $\mathcal{H}_2\otimes\mathcal{L}_2$ joint error measure. The capabilities of these approaches are illustrated by several numerical examples from technical applications.

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43

Oloungha, Stephane B. "Convergence analysis of symmetric interpolatory subdivision schemes." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5268.

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44

Dudziak, William James. "PRESENTATION AND ANALYSIS OF A MULTI-DIMENSIONAL INTERPOLATION FUNCTION FOR NON-UNIFORM DATA: MICROSPHERE PROJECTION." University of Akron / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=akron1183403994.

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45

Miranda, Gerald N. "Interpolation weights of algebraic multigrid." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1997. http://handle.dtic.mil/100.2/ADA334079.

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46

Gandhi, Sonia. "ENO interpolation for image compression." Diss., Connect to online resource, 2005. http://wwwlib.umi.com/cr/colorado/fullcit?p1425778.

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47

Huang, Wei-Feng, and 黃偉峰. "Three Dimensional Circular Interpolator in CNC." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/28161191013350058017.

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碩士
國立中央大學
機械工程研究所
91
The control of CNC machine tools developed by G-Code and M-Code produce cutting route. According to the description of G-Code, three axes of a CNC machine tools can be moved within a desired small distance in each interpolation interrupt. In this thesis, the G-Code commands, like G01 (linear interpolation) and G02 (circular interpolation), are changed to 3D circular interpolation to reduce huge data amount and memory waste. Furthermore, the discontinuity between two G-Codes will be reduced and manufacturing time will be shortened. The purpose of the developed 3D circular interpolation compete NURBS interpolation in performance in manufacture industry. Besides, the 3D circular arcs approximation has been developed to combine 3D circular interpolation to fit curves and can promise G1 and near G2 continuity between two 3D circular arcs. All that we do is to approximate a curve by 3D circular arcs and simulate the CNC machine core, thus we can cut any curve or circular arc in any plane.

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48

Fan, Chin-Hon, and 范正宏. "An Interpolator for Optical Incremental Encoders." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/19137893674627824080.

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碩士
國立交通大學
電子工程系
87
Optical incremental encoders are used to gauge the displacement or the angle of tool machines etc. This thesis investigated the design and hardware implementation of higher interpolation circuits. By subdividing of encoder output signals the measured resolution can be upgraded twenty times and achieves to the range of 1 micrometer. Error analysis of possible methods is discussed in this thesis, and the experiment results will offer us an information for the implement of subdivided circuits.

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49

Cheng, Chien-Kang, and 程建綱. "Multi-precision Function Interpolator for Multimedia Applications." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/19404779468527262033.

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碩士
國立中山大學
資訊工程學系研究所
100
A multi-precision function interpolator, which is fitted in with the IEEE-754 single precision floating point standard, is proposed in this paper. It provides logarithms, exponentials, reciprocal and square root reciprocal operations. Each operation is able to dynamically select four different precision modes in demand. The hardware architecture is designed with fully pipeline in order to comply with hardware architectures of general digital signal processors (DSPs) and graphics processors (GPUs). When considering the usefulness of each precision mode, it is designed to minimize the error among various modes as far as possible in the beginning. According to the precision from high to low, function interpolator can provide 23, 18, 13 and 8-bit accuracy respectively in spite of the rounding effect. This function interpolator is designed based on the look-up table method. It can get the approximation value of target function through the calculation of quadratic polynomial. The coefficient of quadratic polynomial is obtained by piecewise minimax approximation. Before implementing the hardware, we use the Maple algebra software to generate the quadratic polynomial coefficients of aforementioned four operations, and estimate whether these coefficients can meet IEEE-754 single precision floating point standard. In addition, we take the exhaustive search to check the results generated by our implementation to make sure that it can meet the requirements for various operations and precision modes. When performing one of the above four operations, only the tables of the operation are used to obtain the quadratic polynomial coefficient. Therefore, we can take the advantage of the tri-state buffer as a switch to reduce dynamic power consumption of tables for the other three operations. In addition, when performing lower precision modes, we can turn off a part of hardwares, which are used to calculate the quadratic polynomial, to save the power consumption more effectively. By providing multi-precision hardware, we hope users or developers, those who use the battery device, can choose a lower precision mode within the permissible error range to extend the battery life.

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Lai, Shiuan-Hung, and 賴宣宏. "Design of Arc-Length Parameterized NURBS Curve Interpolator." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/73988884066689176552.

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碩士
國立交通大學
機械工程系所
97
Modern CNC systems are designed with the function of arbitrary parametric curves to save massive data communication between CAD/CAM and CNC systems and improve their machining quality. However, the computation loads of NURBS interpolator by numerical methods are relatively large. In this paper, a real-time NURBS motion command generator is presented; this method efficiently integrates the data processing of a NURBS path in a CNC controller, from pre-processing to real-time interpolation. The key point is to generate the arc-length parameterized NURBS curves, in the real-time NURBS path interpolation, the new setting path points can be calculated fast and directly using the arc-length parameterized NURBS curves without the need for any time-consuming computation of NURBS derivatives and iteration. The comparative results of different interpolation algorithms show that the mean-square feedrate deviation of the proposed method is the smallest among all algorithms. Furthermore, comparison of the average computing times of different algorithms show the excellent performance of the arc-length parameterized NURBS path interpolation method – using the same CPU clock, the proposed method is approximately five times faster. The proposed method is numerically stable and does not have the problems of error accumulation.

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Dissertations / Theses on the topic 'Interpolator'

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