Готові списки джерел за темами / Modulating functions method

Зміст

Статті в журналах
Дисертації
Книги
Частини книг
Тези доповідей конференцій
Звіти організацій

Добірка наукової літератури з теми "Modulating functions method"

Автор: Grafiati

Опубліковано: 18 січня 2024

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями

Оберіть тип джерела:

Ознайомтеся зі списками актуальних статей, книг, дисертацій, тез та інших наукових джерел на тему "Modulating functions method".

Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.

Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.

Статті в журналах з теми "Modulating functions method"

Stark, Oliver, Marius Eckert, Albertus Johannes Malan, and Sören Hohmann. "Fractional Systems’ Identification Based on Implicit Modulating Functions." Mathematics 10, no. 21 (November 3, 2022): 4106. http://dx.doi.org/10.3390/math10214106.

Повний текст джерела

Анотація:

This paper presents a new method for parameter identification based on the modulating function method for commensurable fractional-order models. The novelty of the method lies in the automatic determination of a specific modulating function by controlling a model-based auxiliary system, instead of applying and parameterizing a generic modulating function. The input signal of the model-based auxiliary system used to determine the modulating function is designed such that a separate identification of each individual parameter of the fractional-order model is enabled. This eliminates the shortcomings of the common modulating function method in which a modulating function must be adapted to the investigated system heuristically.

Стилі APA, Harvard, Vancouver, ISO та ін.

Liu, Da-Yan, and Taous-Meriem Laleg-Kirati. "Robust fractional order differentiators using generalized modulating functions method." Signal Processing 107 (February 2015): 395–406. http://dx.doi.org/10.1016/j.sigpro.2014.05.016.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Tarasenko, Anna. "Method of SAR sounding signals investigation and digital forming." ITM Web of Conferences 30 (2019): 15030. http://dx.doi.org/10.1051/itmconf/20193015030.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Fedele, Giuseppe, and Loredana Coluccio. "A recursive scheme for frequency estimation using the modulating functions method." Applied Mathematics and Computation 216, no. 5 (May 2010): 1393–400. http://dx.doi.org/10.1016/j.amc.2010.02.039.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Pumaricra Rojas, David, Matti Noack, Johann Reger, and Gustavo Pérez-Zúñiga. "State Estimation for Coupled Reaction-Diffusion PDE Systems Using Modulating Functions." Sensors 22, no. 13 (July 2, 2022): 5008. http://dx.doi.org/10.3390/s22135008.

Повний текст джерела

Анотація:

Many systems with distributed dynamics are described by partial differential equations (PDEs). Coupled reaction-diffusion equations are a particular type of these systems. The measurement of the state over the entire spatial domain is usually required for their control. However, it is often impossible to obtain full state information with physical sensors only. For this problem, observers are developed to estimate the state based on boundary measurements. The method presented applies the so-called modulating function method, relying on an orthonormal function basis representation. Auxiliary systems are generated from the original system by applying modulating functions and formulating annihilation conditions. It is extended by a decoupling matrix step. The calculated kernels are utilized for modulating the input and output signals over a receding time window to obtain the coefficients for the basis expansion for the desired state estimation. The developed algorithm and its real-time functionality are verified via simulation of an example system related to the dynamics of chemical tubular reactors and compared to the conventional backstepping observer. The method achieves a successful state reconstruction of the system while mitigating white noise induced by the sensor. Ultimately, the modulating function approach represents a solution for the distributed state estimation problem without solving a PDE online.

Стилі APA, Harvard, Vancouver, ISO та ін.

Preisig, H. A., and D. W. T. Rippin. "Theory and application of the modulating function method—II. algebraic representation of Maletinsky's spline-type modulating functions." Computers & Chemical Engineering 17, no. 1 (January 1993): 17–28. http://dx.doi.org/10.1016/0098-1354(93)80002-5.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

He, Shanghong. "PARAMETER ESTIMATION OF LINEAR CONTINUOUS-TIME DYNAMIC SYSTEM USING MODULATING FUNCTIONS METHOD." Chinese Journal of Mechanical Engineering 39, no. 12 (2003): 129. http://dx.doi.org/10.3901/jme.2003.12.129.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Fedele, G., C. Picardi, and D. Sgro. "A Power Electrical Signal Tracking Strategy Based on the Modulating Functions Method." IEEE Transactions on Industrial Electronics 56, no. 10 (October 2009): 4079–87. http://dx.doi.org/10.1109/tie.2009.2028352.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Preisig, H. A., and D. W. T. Rippin. "Theory and application of the modulating function method—I. Review and theory of the method and theory of the spline-type modulating functions." Computers & Chemical Engineering 17, no. 1 (January 1993): 1–16. http://dx.doi.org/10.1016/0098-1354(93)80001-4.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Co, Tomas B., and Sridhar Ungarala. "Batch scheme recursive parameter estimation of continuous-time systems using the modulating functions method." Automatica 33, no. 6 (June 1997): 1185–91. http://dx.doi.org/10.1016/s0005-1098(97)00020-4.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Більше джерел

Дисертації з теми "Modulating functions method"

Carlson, Steven D. "Investigation of an in-situ method for determining the modulation transfer function and its applications in a microlithographic wafer stepper /." Online version of thesis, 1990. http://hdl.handle.net/1850/11325.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Wang, Zhibo. "Estimations non-asymptotiques et robustes basées sur des fonctions modulatrices pour les systèmes d'ordre fractionnaire." Electronic Thesis or Diss., Bourges, INSA Centre Val de Loire, 2023. http://www.theses.fr/2023ISAB0003.

Повний текст джерела

Анотація:

Cette thèse développe la méthode des fonctions modulatrices pour des estimations non-asymptotiques et robustes pour des pseudo-états des systèmes nonlinéaires d'ordre fractionnaire, des systèmes linéaires d'ordre fractionnaire avec des accélérations en sortie, et des systèmes à retards d'ordre fractionnaire. Les estimateurs conçus sont fournis en termes de formules intégrales algébriques, ce qui assure une convergence non-asymptotique. Comme une caractéristique essentielle des algorithmes d'estimation conçus, les mesures de sorties bruitées ne sont impliquées que dans les termes intégraux, ce qui confère aux estimateurs une robustesse contre les bruits. Premièrement, pour les systèmes nonlinéaires d'ordre fractionnaire et partiellement inconnu, l'estimation de la dérivée fractionnaire du pseudo-état est abordée via la méthode des fonctions modulatrices. Grâce à la loi de l'indice additif des dérivées fractionnaires, l'estimation est décomposée en une estimation des dérivées fractionnaires de la sortie et une estimation des valeurs initiales fractionnaires. Pendant ce temps, la partie inconnue est estimée via une stratégie innovante de fenêtre glissante. Deuxièmement, pour les systèmes linéaires d'ordre fractionnaire avec des accélérations comme sortie, l'estimation de l'intégrale fractionnaire de l'accélération est d'abord considérée pour les systèmes mécaniques de vibration d'ordre fractionnaire, où seules des mesures d'accélération bruitées sont disponibles. Basée sur des approches numériques existantes qui traitent des intégrales fractionnaires, notre attention se limite principalement à l'estimation des valeurs initiales inconnues en utilisant la méthode des fonctions modulatrices. Sur cette base, le résultat est ensuite généralisé aux systèmes linéaires plus généraux d'ordre fractionnaire. En particulier, le comportement des dérivées fractionnaires à zéro est étudié pour des fonctions absolument continues, ce qui est assez différent de celui de l'ordre entier. Troisièment, pour les systèmes à retards d'ordre fractionnaire, l'estimation du pseudo-état est étudiée en concevant un système dynamique auxiliaire d'ordre fractionnaire, qui fournit un cadre plus général pour générer les fonctions modulatrices requises. Avec l'introduction de l'opérateur de retard et du changement de coordonnées généralisé bicausal, l'estimation du pseudo-état du système considéré peut être réduite à celle de la forme normale correspondante. Contrairement aux travaux précédents le schéma présenté permet une estimation directe du pseudo-état plutôt que d'estimer les dérivées fractionnaires de la sortie et un ensemble de valeurs initiales fractionnaires. De plus, l'efficacité et la robustesse des estimateurs proposés sont vérifiées par des simulations numériques dans cette thèse. Enfin, un résumé de ce travail et un aperçu des travaux futurs sont tirés
This thesis develops the modulating functions method for non-asymptotic and robust estimations for fractional-order nonlinear systems, fractional-order linear systems with accelerations as output, and fractional-order time-delay systems. The designed estimators are provided in terms of algebraic integral formulas, which ensure non-asymptotic convergence. As an essential feature of the designed estimation algorithms, noisy output measurements are only involved in integral terms, which endows the estimators with robustness against corrupting noises. First, for fractional-order nonlinear systems which are partially unknown, fractional derivative estimation of the pseudo-state is addressed via the modulating functions method. Thanks to the additive index law of fractional derivatives, the estimation is decomposed into the fractional derivatives estimation of the output and the fractional initial values estimation. Meanwhile, the unknown part is fitted via an innovative sliding window strategy. Second, for fractional-order linear systems with accelerations as output, fractional integral estimation of the acceleration is firstly considered for fractional-order mechanical vibration systems, where only noisy acceleration measurements are available. Based on the existing numerical approaches addressing the proper fractional integrals of accelerations, our attention is primarily restricted to estimating the unknown initial values using the modulating functions method. On this basis, the result is further generalized to more general fractional-order linear systems. In particular, the behaviour of fractional derivatives at zero is studied for absolutely continuous functions, which is quite different from that of integer order. Third, for fractional-order time-delay systems, pseudo-state estimation is studied by designing a fractional-order auxiliary modulating dynamical system, which provides a more general framework for generating the required modulating functions. With the introduction of the delay operator and the bicausal generalized change of coordinates, the pseudo-state estimation of the considered system can be reduced to that of the corresponding observer normal form. In contrast to the previous work, the presented scheme enables direct estimation for the pseudo-state rather than estimating the fractional derivatives of the output and a bunch of fractional initial values. In addition, the efficiency and robustness of the proposed estimators are verified by numerical simulations in this thesis. Finally, a summary of this work and an insight into future work were drawn

Стилі APA, Harvard, Vancouver, ISO та ін.

Harris, Lara. "Development of a modulation transfer function-based method for evaluating bass reproduction accuracy in professional monitoring loudspeakers." Thesis, University of Southampton, 2015. https://eprints.soton.ac.uk/397270/.

Повний текст джерела

Анотація:

This study develops a measure which allows visual and quantitative assessment of bass reproduction accuracy in professional studio monitors. This type of loudspeaker must present mix engineers in particular with a faithful impression of recordings; they can then create an optimum musical balance between instruments that will translate well to other reproduction systems. Inaccurate monitors can lead to expensive remixing or a degraded musical experience for the end consumers, especially if the fundamental rhythm section has been poorly adjusted. Existing work suggested that the Modulation Transfer Function (MTF) might be a more informative descriptor of bass reproduction accuracy than typical steady-state measures; it might therefore provide a grading system of performance that engineers could use when selecting suitable monitors for their work. The purpose of this project was to investigate the technique and i) develop an algorithm to summarise the critical aspects of monitor performance at low frequencies and ii) see whether it predicted the subjective impression of reproduction accuracy. An algorithm was developed, considering different calculation methods and parameters to optimise it for low-frequency application with musical signals. It was applied to groups of loudspeaker models, simulating the responses of real mix monitors; then listening tests were conducted with these models reproducing music. The subjective and objective results were compared to see whether the algorithm would be a useful measure of monitor performance. The algorithm successfully summarised behaviour of simulated and measured monitor responses; it described important factors such as extension and smoothness, and how the system responded to temporally-varying input signals. Based on ordinal data, the algorithm was found to predict all statistically significant judgements from listeners. These participants had demonstrated that they were accurate and consistent listeners, but found it difficult to reach consensus in some evaluations where the listening task required more skilled judgements of overall performance. It was concluded that the algorithm in its current form is effective and suitable for the intended application, but subjective evaluations of more complex alignments are needed from professional mix engineers; this might allow the numerical MTF scores to be graded against perceived bass reproduction accuracy, therefore enhancing the predictive power of the technique.

Стилі APA, Harvard, Vancouver, ISO та ін.

Tinaztepe, Ramazan. "Modulation spaces, BMO and the Zak transform, and minimizing IPH functions over the unit simplex." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34659.

Повний текст джерела

Анотація:

This thesis consists of two parts. In the first chapter, we give some results on modulation spaces. First the relationship between the classical spaces and the modulation spaces is established. It is proved that certain modulation spaces defined on R² lie in the BMO space. Another result is that the Zak transform, a discrete time-frequency transform, maps a modulation space into a higher dimensional modulation space. And by using these results, an uncertainty principle for Gabor frames via modulation spaces is obtained. In the second part, we deal with optimization of an increasing positively homogeneous functions on the unit simplex. The class of increasing positively homogeneous functions is one of the function classes obtained via min-type functions in the context of abstract convexity. The cutting angle method is used for the minimization of this type functions. The most important step of this method is the minimization of a function which is the maximum of a number of min-type functions on the unit simplex. We propose a numerical algorithm for the minimization of such functions on the unit simplex and we mathematically prove that this algorithm finds the exact solution of the minimization problem. Some experiments have been carried out and the results of the experiments have been presented.

Стилі APA, Harvard, Vancouver, ISO та ін.

Dhuness, Kahesh. "An offset modulation method used to control the PAPR of an OFDM transmission." Thesis, University of Pretoria, 2012. http://hdl.handle.net/2263/27258.

Повний текст джерела

Анотація:

Orthogonal frequency division multiplexing (OFDM) has become a very popular method for high-data-rate communication. However, it is well known that OFDM is plagued by a large peak-to-average power ratio (PAPR) problem. This high PAPR results in overdesigned power amplifiers, which amongst other things leads to inefficient amplifier usage, which is undesirable. Various methods have been recommended to reduce the PAPR of an OFDM transmission; however, all these methods result in a number of drawbacks. In this thesis, a novel method called offset modulation (OM-OFDM) is proposed to control the PAPR of an OFDM signal. The proposed OM-OFDM method does not result in a number of the drawbacks being experienced by current methods in the field. The theoretical bandwidth occupancy and theoretical bit error rate (BER) expression for an OM-OFDM transmission is derived. A newly applied power performance decision metric is also introduced, which can be utilised throughout the PAPR field, in order to compare various methods. The proposed OM-OFDM method appears to be similar to a well-known constant envelope OFDM (CE-OFDM) transmission. The modulation, structural and performance differences between an OM-OFDM and a CE-OFDM method are discussed. By applying the power performance decision metric, the OM-OFDM method is shown to offer significant performance gains when compared to CE-OFDM and traditional OFDM transmissions. In addition, the OM-OFDM method is able to accurately control the PAPR of a transmission for a targeted BER. By applying the power performance decision metric and complementary cumulative distribution function (CCDF), the proposed OM-OFDM method is shown to offer further performance gains when compared to existing PAPR methods, under frequency selective fading conditions. In this thesis, the OM-OFDM method has been combined with an existing active constellation extended (ACE) PAPR reduction method. To introduce a novel method called offset modulation with active constellation extension (OM-ACE), to control the PAPR of an OFDM signal. The theoretical BER expression for an OM-ACE transmission is presented and validated. Thereafter, by applying the decision metric and CCDF, the OM-ACE method is shown to offer performance improvements when compared to various PAPR methods. The use of OM-OFDM for cognitive radio applications is also investigated. Cognitive radio applications require transmissions that are easily detectable. The detection characteristics of an OM-OFDM and OFDM transmission are studied by using receiver operating characteristic curves. A derivation of a simplified theoretical closed-form expression, which relates the probability of a missed detection to the probability of a false alarm, for an unknown deterministic signal, at various signal-to-noise ratio (SNR) values is derived and validated. Previous expressions have been derived, which relate the probability of a missed detection to the probability of a false alarm. However, they have not been presented in such a generic closed-form expression that can be used for any unknown deterministic signal (for instance OFDM and OM-OFDM). Thereafter, an examination of the spectrum characteristics of an OM-OFDM transmission indicates its attractive detection characteristics. The proposed OM-OFDM method is further shown to operate at a significantly lower SNR value than an OFDM transmission, while still offering better detection characteristics than that of an OFDM transmission under Rician, Rayleigh and frequency selective fading channel conditions. In addition to its attractive PAPR properties, OM-OFDM also offers good detection characteristics for cognitive radio applications. These aspects make OM-OFDM a promising candidate for future deployment.
Thesis (PhD)--University of Pretoria, 2012.
Electrical, Electronic and Computer Engineering
unrestricted

Стилі APA, Harvard, Vancouver, ISO та ін.

Li, Tianya. "Electromechanical wave propagation phenomenon and its control implications in power systems." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/95962/1/Tianya_Li_Thesis.pdf.

Повний текст джерела

Анотація:

This thesis investigates advanced control methods and strategies to enhance the transient stability of a power system which is affected by the electromechanical wave propagation phenomenon. The characteristics of the travelling wave phenomenon and its impact on system separation during first swing are investigated in detail. This thesis identifies four innovative control implications for power system stability and proposes an improved method to enhance power system transient stability. By designing better control of existing equipment, this research achieves increased maximum power transfer under contingencies in a cost efficient and readily implemented way.

Стилі APA, Harvard, Vancouver, ISO та ін.

Almér, Stefan. "Control and Analysis of Pulse-Modulated Systems." Doctoral thesis, KTH, Optimeringslära och systemteori, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4713.

Повний текст джерела

Анотація:

The thesis consists of an introduction and four appended papers. In the introduction we give an overview of pulse-modulated systems and provide a few examples of such systems. Furthermore, we introduce the so-called dynamic phasor model which is used as a basis for analysis in two of the appended papers. We also introduce the harmonic transfer function and finally we provide a summary of the appended papers. The first paper considers stability analysis of a class of pulse-width modulated systems based on a discrete time model. The systems considered typically have periodic solutions. Stability of a periodic solution is equivalent to stability of a fixed point of a discrete time model of the system dynamics. Conditions for global and local exponential stability of the discrete time model are derived using quadratic and piecewise quadratic Lyapunov functions. A griding procedure is used to develop a systematic method to search for the Lyapunov functions. The second paper considers the dynamic phasor model as a tool for stability analysis of a general class of pulse-modulated systems. The analysis covers both linear time periodic systems and systems where the pulse modulation is controlled by feedback. The dynamic phasor model provides an $\textbf{L}_2$-equivalent description of the system dynamics in terms of an infinite dimensional dynamic system. The infinite dimensional phasor system is approximated via a skew truncation. The truncated system is used to derive a systematic method to compute time periodic quadratic Lyapunov functions. The third paper considers the dynamic phasor model as a tool for harmonic analysis of a class of pulse-width modulated systems. The analysis covers both linear time periodic systems and non-periodic systems where the switching is controlled by feedback. As in the second paper of the thesis, we represent the switching system using the L_2-equivalent infinite dimensional system provided by the phasor model. It is shown that there is a connection between the dynamic phasor model and the harmonic transfer function of a linear time periodic system and this connection is used to extend the notion of harmonic transfer function to describe periodic solutions of non-periodic systems. The infinite dimensional phasor system is approximated via a square truncation. We assume that the response of the truncated system to a periodic disturbance is also periodic and we consider the corresponding harmonic balance equations. An approximate solution of these equations is stated in terms of a harmonic transfer function which is analogous to the harmonic transfer function of a linear time periodic system. The aforementioned assumption is proved to hold for small disturbances by proving the existence of a solution to a fixed point equation. The proof implies that for small disturbances, the approximation is good. Finally, the fourth paper considers control synthesis for switched mode DC-DC converters. The synthesis is based on a sampled data model of the system dynamics. The sampled data model gives an exact description of the converter state at the switching instances, but also includes a lifted signal which represents the inter-sampling behavior. Within the sampled data framework we consider H-infinity control design to achieve robustness to disturbances and load variations. The suggested controller is applied to two benchmark examples; a step-down and a step-up converter. Performance is verified in both simulations and in experiments.
QC 20100628

Стилі APA, Harvard, Vancouver, ISO та ін.

Muševič, Sašo. "Non-stationary sinusoidal analysis." Doctoral thesis, Universitat Pompeu Fabra, 2013. http://hdl.handle.net/10803/123809.

Повний текст джерела

Анотація:

Muchos tipos de señales que encontramos a diario pertenecen a la categoría de sinusoides no estacionarias. Una gran parte de esas señales son sonidos que presentan una gran variedad de características: acústicos/electrónicos, sonidos instrumentales harmónicos/impulsivos, habla/canto, y la mezcla de todos ellos que podemos encontrar en la música. Durante décadas la comunidad científica ha estudiado y analizado ese tipo de señales. El motivo principal es la gran utilidad de los avances científicos en una gran variedad de áreas, desde aplicaciones médicas, financiera y ópticas, a procesado de radares o sonar, y también a análisis de sistemas. La estimación precisa de los parámetros de sinusoides no estacionarias es una de las tareas más comunes en procesado digital de señales, y por lo tanto un elemento fundamental e indispensable para una gran variedad de aplicaciones. Las transformaciones de tiempo y frecuencia clásicas son solamente apropiadas para señales con variación lenta de amplitud y frecuencia. Esta suposición no suele cumplirse en la práctica, lo que conlleva una degradación de calidad y la aparición de artefactos. Además, la resolución temporal y frecuencial no se puede incrementar arbitrariamente debido al conocido principio de incertidumbre de Heisenberg. \\ El principal objetivo de esta tesis es revisar y mejorar los métodos existentes para el análisis de sinusoides no estacionarias, y también proponer nuevas estrategias y aproximaciones. Esta disertación contribuye sustancialmente a los análisis sinusoidales existentes: a) realiza una evaluación crítica del estado del arte y describe con gran detalle los métodos de análisis existentes, b) aporta mejoras sustanciales a algunos de los métodos existentes más prometedores, c) propone varias aproximaciones nuevas para el análisis de los modelos sinusoidales existentes i d) propone un modelo sinusoidal muy general y flexible con un algoritmo de análisis directo y rápido.
Many types of everyday signals fall into the non-stationary sinusoids category. A large family of such signals represent audio, including acoustic/electronic, pitched/transient instrument sounds, human speech/singing voice, and a mixture of all: music. Analysis of such signals has been in the focus of the research community for decades. The main reason for such intense focus is the wide applicability of the research achievements to medical, financial and optical applications, as well as radar/sonar signal processing and system analysis. Accurate estimation of sinusoidal parameters is one of the most common digital signal processing tasks and thus represents an indispensable building block of a wide variety of applications. Classic time-frequency transformations are appropriate only for signals with slowly varying amplitude and frequency content - an assumption often violated in practice. In such cases, reduced readability and the presence of artefacts represent a significant problem. Time and frequency resolu

Стилі APA, Harvard, Vancouver, ISO та ін.

Asiri, Sharefa M. "Modulating Function-Based Method for Parameter and Source Estimation of Partial Differential Equations." Diss., 2017. http://hdl.handle.net/10754/625846.

Повний текст джерела

Анотація:

Partial Differential Equations (PDEs) are commonly used to model complex systems that arise for example in biology, engineering, chemistry, and elsewhere. The parameters (or coefficients) and the source of PDE models are often unknown and are estimated from available measurements. Despite its importance, solving the estimation problem is mathematically and numerically challenging and especially when the measurements are corrupted by noise, which is often the case. Various methods have been proposed to solve estimation problems in PDEs which can be classified into optimization methods and recursive methods. The optimization methods are usually heavy computationally, especially when the number of unknowns is large. In addition, they are sensitive to the initial guess and stop condition, and they suffer from the lack of robustness to noise. Recursive methods, such as observer-based approaches, are limited by their dependence on some structural properties such as observability and identifiability which might be lost when approximating the PDE numerically. Moreover, most of these methods provide asymptotic estimates which might not be useful for control applications for example. An alternative non-asymptotic approach with less computational burden has been proposed in engineering fields based on the so-called modulating functions. In this dissertation, we propose to mathematically and numerically analyze the modulating functions based approaches. We also propose to extend these approaches to different situations. The contributions of this thesis are as follows. (i) Provide a mathematical analysis of the modulating function-based method (MFBM) which includes: its well-posedness, statistical properties, and estimation errors. (ii) Provide a numerical analysis of the MFBM through some estimation problems, and study the sensitivity of the method to the modulating functions' parameters. (iii) Propose an effective algorithm for selecting the method's design parameters. (iv) Develop a two-dimensional MFBM to estimate space-time dependent unknowns which is illustrated in estimating the source term in the damped wave equation describing the physiological characterization of brain activity. (v) Introduce a moving horizon strategy in the MFBM for on-line estimation and examine its effectiveness on estimating the source term of a first order hyperbolic equation which describes the heat transfer in distributed solar collector systems.

Стилі APA, Harvard, Vancouver, ISO та ін.

Aldoghaither, Abeer. "Methods and Algorithms for Solving Inverse Problems for Fractional Advection-Dispersion Equations." Diss., 2015. http://hdl.handle.net/10754/582312.

Повний текст джерела

Анотація:

Fractional calculus has been introduced as an e cient tool for modeling physical phenomena, thanks to its memory and hereditary properties. For example, fractional models have been successfully used to describe anomalous di↵usion processes such as contaminant transport in soil, oil flow in porous media, and groundwater flow. These models capture important features of particle transport such as particles with velocity variations and long-rest periods. Mathematical modeling of physical phenomena requires the identification of pa- rameters and variables from available measurements. This is referred to as an inverse problem. In this work, we are interested in studying theoretically and numerically inverse problems for space Fractional Advection-Dispersion Equation (FADE), which is used to model solute transport in porous media. Identifying parameters for such an equa- tion is important to understand how chemical or biological contaminants are trans- ported throughout surface aquifer systems. For instance, an estimate of the di↵eren- tiation order in groundwater contaminant transport model can provide information about soil properties, such as the heterogeneity of the medium. Our main contribution is to propose a novel e cient algorithm based on modulat-ing functions to estimate the coe cients and the di↵erentiation order for space FADE, which can be extended to general fractional Partial Di↵erential Equation (PDE). We also show how the method can be applied to the source inverse problem. This work is divided into two parts: In part I, the proposed method is described and studied through an extensive numerical analysis. The local convergence of the proposed two-stage algorithm is proven for 1D space FADE. The properties of this method are studied along with its limitations. Then, the algorithm is generalized to the 2D FADE. In part II, we analyze direct and inverse source problems for a space FADE. The problem consists of recovering the source term using final observations. An analytic solution for the non-homogeneous case is derived and existence and uniqueness of the solution are established. In addition, the uniqueness and stability of the inverse problem is studied. Moreover, the modulating functions-based method is used to solve the problem and it is compared to a standard Tikhono-based optimization technique.

Стилі APA, Harvard, Vancouver, ISO та ін.

Більше джерел

Книги з теми "Modulating functions method"

International Commission on Radiation Units and Measurements., ed. Modulation transfer function of screen-film systems. Bethesda, Md., U.S.A: The Commission, 1986.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Q, Pan J., and United States. National Aeronautics and Space Administration., eds. Frequency analysis via the method of moment functionals. [Washington, D.C: National Aeronautics and Space Administration, 1990.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Hoeschen, D. Determination of the modulation transfer function of screen-film combinations in X-ray photography by the grating method. Luxembourg: Commission of the European Communities, 1987.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Veshkurtsev, Yury. THE FOUNDATIONS OF THE THEORY OF CONSTRUCTION OF NEW-GENERATION MODEMS. au: AUS PUBLISHERS, 2022. http://dx.doi.org/10.26526/monography_628a8925151ca0.71125494.

Повний текст джерела

Анотація:

The monography presents the fundamentals of the theory of construction new-generation modems. Modems are built on the principles of statistical communication theory, based on the use of a random signal (chaos) as a carrier of information. In such a signal, a characteristic function is modulated, which is a fundamental characteristic of a random process. The signal modulation and demodulation method is patented and allows you to create modems with efficiency and noise immunity indicators several orders of magnitude higher than those of the known devices of the same name. New-generation modems immediately improve the technical characteristics of digital IT equipment by several orders of magnitude, since they work without errors in wired and radio channels when receiving one hundred duodecillion of binary symbols. The book is recommended for scientists and specialists in the field of digital communication systems, statistical radio engineering and instrumentation, and may be useful for graduate students, masters and students of relevant specialties.

Стилі APA, Harvard, Vancouver, ISO та ін.

Montgomery, H. E. Sensor performance analysis. Washington, D.C: National Aeronautics and Space Administration, Office of Management, Scientific and Technical Information Division, 1990.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Montgomery, H. E. Sensor performance analysis. Washington, D.C: National Aeronautics and Space Administration, Office of Management, Scientific and Technical Information Division, 1990.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Montgomery, H. E. Sensor performance analysis. Greenbelt, Md: Goddard Space Flight Center, 1990.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Robertson, Ian H., and Redmond G. O'Connell. Rehabilitation of Attention Functions. Edited by Anna C. (Kia) Nobre and Sabine Kastner. Oxford University Press, 2014. http://dx.doi.org/10.1093/oxfordhb/9780199675111.013.021.

Повний текст джерела

Анотація:

The evidence for the effectiveness of rehabilitation of three types of attention—selectivity, sustained attention, and attentional switching—is reviewed. Limited but significant effects in all three domains are observed, though evidence for generalization to wider everyday life functions remains relatively sparse. In the case of sustained attention and also in the case of spatial selectivity, the modulating effects of arousal are shown to be important, and higher level executive deficits may at times be exacerbated or even caused by lowered levels of arousal. Conversely, methods of modulating arousal may be used to improve sustained attention and executive functions in a range of clinical conditions. Attentional functions are key to other cognitive domains such as attention and perception, and so the promising evidence for attentional rehabilitation may contribute to the rehabilitation of other cognitive domains also.

Стилі APA, Harvard, Vancouver, ISO та ін.

Chen, Robert, and john rothwell. Cortical Connectivity: Brain Stimulation for Assessing and Modulating Cortical Connectivity and Function. Springer London, Limited, 2012.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Chen, Robert, and john rothwell. Cortical Connectivity: Brain Stimulation for Assessing and Modulating Cortical Connectivity and Function. Springer, 2014.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Більше джерел

Частини книг з теми "Modulating functions method"

Jones, Huw D. "Gene silencing or gene editing: the pros and cons." In RNAi for plant improvement and protection, 47–53. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789248890.0006.

Повний текст джерела

Анотація:

Abstract Research into plant genetics often requires the suppression or complete knockout of gene expression to scientifically validate gene function. In addition, the phenotypes obtained from gene suppression can occasionally have commercial value for plant breeders. Until recently, the methodological choices to achieve these goals fell into two broad types: either some form of RNA-based gene silencing; or the screening of large numbers of natural or induced random genomic mutations. The more recent invention of gene editing as a tool for targeted mutation potentially gives researchers and plant breeders another route to block gene function. RNAi is widely used in animal and plant research and functions to silence gene expression by degrading the target gene transcript. Although RNAi offers unique advantages over genomic mutations, it often leads to the formation of a genetically modified organism (GMO), which for commercial activities has major regulatory and acceptance issues in some regions of the world. Traditional methods of generating genomic mutations are more laborious and uncertain to achieve the desired goals but possess a distinct advantage of not being governed by GMO regulations. Gene editing (GE) technologies have some of the advantages of both RNAi and classical mutation breeding in that they can be designed to give simple knockouts or to modulate gene expression more subtly. GE also has a more complex regulatory position, with some countries treating it as another conventional breeding method whilst the EU defines GE as a technique of genetic modification and applies the normal GMO authorization procedures. This chapter explores the pros and cons of RNAi alongside other methods of modulating gene function.

Стилі APA, Harvard, Vancouver, ISO та ін.

Jones, Huw D. "Gene silencing or gene editing: the pros and cons." In RNAi for plant improvement and protection, 47–53. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789248890.0047.

Повний текст джерела

Анотація:

Стилі APA, Harvard, Vancouver, ISO та ін.

Martínez, Claudio, José A. Souto, and Angel R. de Lera. "Ligand Design for Modulation of RXR Functions." In Methods in Molecular Biology, 51–72. New York, NY: Springer New York, 2019. http://dx.doi.org/10.1007/978-1-4939-9585-1_4.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Schellens, Renske, Erik de Vrieze, Ralph Slijkerman, Hannie Kremer, and Erwin van Wijk. "Generation of Humanized Zebrafish Models for the In Vivo Assessment of Antisense Oligonucleotide-Based Splice Modulation Therapies." In Methods in Molecular Biology, 281–99. New York, NY: Springer US, 2022. http://dx.doi.org/10.1007/978-1-0716-2010-6_19.

Повний текст джерела

Анотація:

AbstractAntisense oligonucleotide (AON)-based splice modulation is the most widely used therapeutic approach to redirect precursor messenger RNA (pre-mRNA) splicing. To study the functional effect of humanmutations affecting pre-mRNAsplicing for which AON-based splice redirection would be a potential therapeutic option, humanized knock-in animal models are pivotal. A major limitation of using humanized animal models for this purpose is the reported poor recognition of human splice sites by the splicing machineries of other species. To overcome this problem, we provide a detailed guideline for the generation of functional humanized knock-in zebrafish models to assess the effect of mutation-induced aberrant splicing and subsequent AON-based splice modulation therapy.

Стилі APA, Harvard, Vancouver, ISO та ін.

Veshkurtsev, Yury. "CHARACTERISTIC FUNCTION." In THE FOUNDATIONS OF THE THEORY OF CONSTRUCTION OF NEW-GENERATION MODEMS, 10–25. au: AUS PUBLISHERS, 2022. http://dx.doi.org/10.26526/chapter_628a8925276245.43662054.

Повний текст джерела

Анотація:

Стилі APA, Harvard, Vancouver, ISO та ін.

McCubbrey, Alexandra L., and William J. Janssen. "Modulation of Myeloid Cell Function Using Conditional and Inducible Transgenic Approaches." In Methods in Molecular Biology, 145–68. New York, NY: Springer New York, 2018. http://dx.doi.org/10.1007/978-1-4939-8570-8_13.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Biswal, Bharat B., and Sridhar S. Kannurpatti. "Resting-State Functional Connectivity in Animal Models: Modulations by Exsanguination." In Methods in Molecular Biology, 255–74. Totowa, NJ: Humana Press, 2009. http://dx.doi.org/10.1007/978-1-59745-543-5_12.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Stefanski, Adrianne L., Dorota S. Raclawska, and Christopher M. Evans. "Modulation of Lung Epithelial Cell Function Using Conditional and Inducible Transgenic Approaches." In Methods in Molecular Biology, 169–201. New York, NY: Springer New York, 2018. http://dx.doi.org/10.1007/978-1-4939-8570-8_14.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Sioud, Mouldy. "Modulation of Dendritic Cell Maturation and Function by siRNA-Bearing 5ʹ-Triphosphate." In Methods in Molecular Biology, 393–402. Totowa, NJ: Humana Press, 2010. http://dx.doi.org/10.1007/978-1-60761-657-3_26.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Hwang, Chi-Hung, Wei-Chung Wang, Yung-Hsiang Chen, Te-Heng Hung, and Jia-He Chen. "Indicating DIC Potential Correlation Errors with Optical Modulation Transfer Function." In Advancement of Optical Methods in Experimental Mechanics, Volume 3, 137–44. Cham: Springer International Publishing, 2013. http://dx.doi.org/10.1007/978-3-319-00768-7_16.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Тези доповідей конференцій з теми "Modulating functions method"

Da-Yan Liu, Taous-Meriem Laleg-Kirati, Olivier Gibaru, and Wilfrid Perruquetti. "Identification of fractional order systems using modulating functions method." In 2013 American Control Conference (ACC). IEEE, 2013. http://dx.doi.org/10.1109/acc.2013.6580077.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Coluccio, L., A. Eisinberg, G. Fedele, C. Picardi, and D. Sgro. "Modulating functions method plus SOGI scheme for signal tracking." In 2008 IEEE International Symposium on Industrial Electronics (ISIE 2008). IEEE, 2008. http://dx.doi.org/10.1109/isie.2008.4677143.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Aljehani, Fahad, and Taous-Meriem Laleg-Kirati. "Iterative Learning Based Modulating Functions Method for Distributed Solar Source Estimation." In 2021 American Control Conference (ACC). IEEE, 2021. http://dx.doi.org/10.23919/acc50511.2021.9482958.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Asiri, Sharefa, Da-Yan Liu, and Taous-Meriem Laleg-Kirati. "Modulating functions method for parameters estimation in the fifth order KdV equation." In 2017 25th Mediterranean Conference on Control and Automation (MED). IEEE, 2017. http://dx.doi.org/10.1109/med.2017.7984091.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Wang, Lei, Da-Yan Liu, and Olivier Gibaru. "A new modulating functions method for state estimation of integer order system." In 2022 41st Chinese Control Conference (CCC). IEEE, 2022. http://dx.doi.org/10.23919/ccc55666.2022.9902682.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Asiri, Sharefa. "Modulating functions method for coefficients estimation in the sixth order generalized Boussinesq equation." In The 5th Innovation and Analytics Conference & Exhibition (IACE 2021). AIP Publishing, 2022. http://dx.doi.org/10.1063/5.0092769.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Wei, Xing, Da-Yan Liu, and Driss Boutat. "Extension of modulating functions method to pseudo-state estimation for fractional order linear systems." In 2016 35th Chinese Control Conference (CCC). IEEE, 2016. http://dx.doi.org/10.1109/chicc.2016.7555015.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Liu, Chang, Dayan Liu, Driss Boutat, and Yong Wang. "State Estimation for a Class of Fractional-Order Linear Systems by the Generalized Modulating Functions Method." In 2022 10th International Conference on Systems and Control (ICSC). IEEE, 2022. http://dx.doi.org/10.1109/icsc57768.2022.9993949.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Wang, Zhi-Bo, Da-Yan Liu, Driss Boutat, Yang Tian, and Hao-Ran Liu. "Modulating Functions Based Fast and Robust Estimation for a Class of Fractional Order Vibration Systems." In ASME 2021 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/detc2021-67447.

Повний текст джерела

Анотація:

Abstract This paper aims to fast and robustly estimate the fractional integrals and derivatives of positions from noisy accelerations for a class of fractional order vibration systems defined by the Caputo fractional derivative. The main idea is to convert the original issue into the estimation of the fractional integrals of accelerations and the ones of the unknown initial conditions, on the basis of the additive index law. Being proper integrals, the fractional integrals of accelerations can be estimated via a numerical method. Consequently, solving the original problem boils down to estimating the unknown initial values. To this end, the modulating functions method is adopted. By constructing appropriate modulating functions, the unknown initial values are exactly given in terms of algebraic integral formulas in different situations. Finally, two illustrations are presented to verify the correctness and robustness of the proposed estimators.

Стилі APA, Harvard, Vancouver, ISO та ін.

Wang, Lei, Da-Yan Liu, and Olivier Gibaru. "Estimators for Fractional Derivative and Integral of the State of Linear Systems Based on Modulating Functions Method." In 2023 42nd Chinese Control Conference (CCC). IEEE, 2023. http://dx.doi.org/10.23919/ccc58697.2023.10240361.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Звіти організацій з теми "Modulating functions method"

Schwartz, Bertha, Vaclav Vetvicka, Ofer Danai, and Yitzhak Hadar. Increasing the value of mushrooms as functional foods: induction of alpha and beta glucan content via novel cultivation methods. United States Department of Agriculture, January 2015. http://dx.doi.org/10.32747/2015.7600033.bard.

Повний текст джерела

Анотація:

During the granting period, we performed the following projects: Firstly, we differentially measured glucan content in several pleurotus mushroom strains. Mushroom polysaccharides are edible polymers that have numerous reported biological functions; the most common effects are attributed to β-glucans. In recent years, it became apparent that the less abundant α-glucans also possess potent effects in various health conditions. In our first study, we explored several Pleurotus species for their total, β and α-glucan content. Pleurotuseryngii was found to have the highest total glucan concentrations and the highest α-glucans proportion. We also found that the stalks (stipe) of the fruit body contained higher glucan content then the caps (pileus). Since mushrooms respond markedly to changes in environmental and growth conditions, we developed cultivation methods aiming to increase the levels of α and β-glucans. Using olive mill solid waste (OMSW) from three-phase olive mills in the cultivation substrate. We were able to enrich the levels mainly of α-glucans. Maximal total glucan concentrations were enhanced up to twice when the growth substrate contained 80% of OMSW compared to no OMSW. Taking together this study demonstrate that Pleurotuseryngii can serve as a potential rich source of glucans for nutritional and medicinal applications and that glucan content in mushroom fruiting bodies can be further enriched by applying OMSW into the cultivation substrate. We then compared the immune-modulating activity of glucans extracted from P. ostreatus and P. eryngii on phagocytosis of peripheral blood neutrophils, and superoxide release from HL-60 cells. The results suggest that the anti-inflammatory properties of these glucans are partially mediated through modulation of neutrophileffector functions (P. eryngiiwas more effective). Additionally, both glucans dose-dependently competed for the anti-Dectin-1 and anti-CR3 antibody binding. We then tested the putative anti-inflammatory effects of the extracted glucans in inflammatory bowel disease (IBD) using the dextran sulfate sodium (DSS)–induced model in mice. The clinical symptoms of IBD were efficiently relieved by the treatment with two different doses of the glucan from both fungi. Glucan fractions, from either P. ostreatus or P. eryngii, markedly prevented TNF-α mediated inflammation in the DSS–induced inflamed intestine. These results suggest that there are variations in glucan preparations from different fungi in their anti-inflammatory ability. In our next study, we tested the effect of glucans on lipopolysaccharide (LPS)-induced production of TNF-α. We demonstrated that glucan extracts are more effective than mill mushroom preparations. Additionally, the effectiveness of stalk-derived glucans were slightly more pronounced than of caps. Cap and stalk glucans from mill or isolated glucan competed dose-dependently with anti-Dectin-and anti-CR-3 antibodies, indicating that they contain β-glucans recognized by these receptors. Using the dextran sulfate sodium (DSS)-inflammatory bowel disease mice model, intestinal inflammatory response to the mill preparations was measured and compared to extracted glucan fractions from caps and stalks. We found that mill and glucan extracts were very effective in downregulatingIFN-γ and MIP-2 levels and that stalk-derived preparations were more effective than from caps. The tested glucans were equally effective in regulating the number of CD14/CD16 monocytes and upregulating the levels of fecal-released IgA to almost normal levels. In conclusion, the most effective glucans in ameliorating some IBD-inflammatory associated symptoms induced by DSS treatment in mice were glucan extracts prepared from the stalk of P. eryngii. These spatial distinctions may be helpful in selecting more effective specific anti-inflammatory mushrooms-derived glucans. We additionally tested the effect of glucans on lipopolysaccharide-induced production of TNF-α, which demonstrated stalk-derived glucans were more effective than of caps-derived glucans. Isolated glucans competed with anti-Dectin-1 and anti-CR3 antibodies, indicating that they contain β-glucans recognized by these receptors. In conclusion, the most effective glucans in ameliorating IBD-associated symptoms induced by DSS treatment in mice were glucan extracts prepared from the stalk of P. eryngii grown at higher concentrations of OMSW. We conclude that these stress-induced growing conditions may be helpful in selecting more effective glucans derived from edible mushrooms. Based on the findings that we could enhance glucan content in Pleurotuseryngii following cultivation of the mushrooms on a substrate containing different concentrations of olive mill solid waste (OMSW) and that these changes are directly related to the content of OMSW in the growing substrate we tested the extracted glucans in several models. Using dextran sulfate sodium (DSS)–inflammatory bowel disease (IBD) mice model, we measured the colonic inflammatory response to the different glucan preparations. We found that the histology damaging score (HDS) resulting from DSS treatment reach a value of 11.8 ± 2.3 were efficiently downregulated by treatment with the fungal extracted glucans, glucans extracted from stalks cultivated at 20% OMSWdownregulated to a HDS value of 6.4 ± 0.5 and at 80% OMSW showed the strongest effects (5.5 ± 0.6). Similar downregulatory effects were obtained for expression of various intestinal cytokines. All tested glucans were equally effective in regulating the number of CD14/CD16 monocytes from 18.2 ± 2.7 % for DSS to 6.4 ± 2.0 for DSS +glucans extracted from stalks cultivated at 50% OMSW. We finally tested glucans extracted from Pleurotuseryngii grown on a substrate containing increasing concentrations of olive mill solid waste (OMSW) contain greater glucan concentrations as a function of OMSW content. Treatment of rat Intestinal epithelial cells (IEC-6) transiently transfected with Nf-κB fused to luciferase demonstrated that glucans extracted from P. eryngii stalks grown on 80% OMSWdownregulatedTNF-α activation. Glucans from mushrooms grown on 80% OMSW exerted the most significant reducing activity of nitric oxide production in lipopolysaccharide (LPS) treated J774A.1 murine macrophages. The isolated glucans were tested in vivo using the Dextran Sodium Sulfate (DSS) induced colitis in C57Bl/6 mice and found to reduce the histology damaging score resulting from DSS treatment. Expression of various intestinal cytokines were efficiently downregulated by treatment with the fungal extracted glucans. We conclude that the stress-induced growing conditions exerted by OMSW induces production of more effective anti-inflammatory glucans in P. eryngii stalks.

Стилі APA, Harvard, Vancouver, ISO та ін.

Ми пропонуємо знижки на всі преміум-плани для авторів, чиї праці увійшли до тематичних добірок літератури. Зв'яжіться з нами, щоб отримати унікальний промокод!