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This paper deals with investigating the properties of pseudo-state matrices in multi-order dynamic systems which generate steady-state oscillations combined of some sinusoidal components with different frequencies (multi-frequency steady state oscillations). In this investigation, a Routh array based criterion is found which should be satisfied by the pseudo-state matrix of a multi-order multi-frequency oscillatory system. In design of multi-frequency oscillators, this criterion can be rewritten as a system of monomial equations whose variables are the tunable elements of the pseudo-state matrix of the oscillator. Furthermore, a class of transformations on the pseudo-state matrix of a multi-order multi-frequency oscillator is obtained which can guarantee the preservation of the multi-frequency feature in the dynamic structure constructed based on the transformed pseudo-state matrix. [ABSTRACT FROM AUTHOR]

This paper uses an improved switching table-based direct torque control space vector selection technique with a nine-level hysteresis band to reduce torque ripple in a PMBLDC drive. The commutation torque ripple is mitigated by different rates of correction of torque depending upon the error quantum. Multi-rates of correction are applied using three sets of lookup tables corresponding to low, medium and high torque errors. In general, the existing state of the art incorporates an observer-based controller that optimizes complex objective functions. This increases computational cost and complexity. The proposed method is based on modified switching tables. This decreases the computational cost and improves the dynamic response. Frequency-domain analysis of torque response establishes the minimization of high-frequency components. The experimental validation is obtained on 1 kw BLDC motor using DSPACE 1104 real-time controller. [ABSTRACT FROM AUTHOR]

In this paper, firstly, optimal sizing and placement of photovoltaic-based distributed generation units (PVDGUs) and passive harmonic filters (PFs) are proposed to improve both the PVDGU hosting capacity and bus voltage profile of the distorted radial distribution systems. The objective of the proposed approach (PA) is defined as minimizing the rms deviation and total harmonic distortion of the bus voltages while maximizing the hosting capacity. Its constraints are considered as bus voltage total and individual harmonic distortion limits placed in IEEE standard 519, permissible bus voltage rms intervals, and the numbers and total powers of the PVDGUs and PFs. Secondly, it is aimed to investigate the performance of the PA on the improvement of the hosting capacity and voltage profile. Thus, for the modified IEEE 33 bus test system containing nonlinear loads, it is comparatively evaluated with a traditional PF planning approach (TA) based on minimization of the total voltage harmonic distortion. Finally, the effects of the harmonic analysis algorithm and PVDGU harmonic model preferences on the solutions of both approaches are also analysed. One of the major conclusions obtained from the analysis is that PA achieves significantly higher PVDGU hosting capacity while providing total voltage harmonic distortion mitigation performance very close to TA. In addition, PA achieves almost the same hosting capacity for all considered harmonic models and harmonic analysis algorithms. However, this is not the case for TA. [ABSTRACT FROM AUTHOR]

The motivation to this paper stems from signal/image processing where it is desired to measure various attributes or physical quantities such as position, scale, direction and frequency of a signal or an image. These physical quantities are measured via a signal transform, for example, the short time Fourier transform measures the content of a signal at different times and frequencies. There are well known obstructions for completely accurate measurements formulated as 'uncertainty principles'. It has been shown recently that 'conventional' localization notions, based on variances associated with Lie-group generators and their corresponding uncertainty inequality might be misleading, if they are applied to transformation groups which differ from the Heisenberg group, the latter being prevailing in signal analysis and quantum mechanics. In this paper we describe a generic signal transform as a procedure of measuring the content of a signal at different values of a set of given physical quantities. This viewpoint sheds a light on the relationship between signal transforms and uncertainty principles. In particular we introduce the concepts of 'adjoint translations' and 'adjoint observables', respectively. We show that the fundamental issue of interest is the measurement of physical quantities via the appropriate localization operators termed 'adjoint observables'. It is shown how one can define, for each localization operator, a family of related 'adjoint translation' operators that translate the spectrum of that localization operator. The adjoint translations in the examples of this paper correspond to well-known transformations in signal processing such as the short time Fourier transform (STFT), the continuous wavelet transform (CWT) and the shearlet transform. We show how the means and variances of states transform appropriately under the translation action and compute associated minimizers and equalizers for the uncertainty criterion. Finally, the concept of adjoint observables is used to estimate concentration properties of ambiguity functions, the latter being an alternative localization concept frequently used in signal analysis. [ABSTRACT FROM AUTHOR]

In December 2015 I gave a series of six lectures at the Indian Institute of Science in which I sketched the thematic development of some of the main techniques and results of 20th-century harmonic analysis. The subjects of the lectures were, briefly, as follows: I emphasized interconnections, both the way in which the material in the first lecture provided the roots out of which most of the developments in the other lectures grew, and the ways in which those developments interacted with each other. I included sketches of as many proofs as the time would permit: some very brief, but some fairly complete, especially those whose methodology is an important part of the subject. Much was omitted, of course, and there was a natural bias toward the areas where I have spent periods of my own mathematical life. Many developments, particularly those of the final quarter-century, received at most a brief mention. This paper is a written account of these lectures with a few more details fleshed out, a few topics reorganized, and a few items added. I hope that others may find it an interesting narrative and a useful reference, and that it may lead some of them to share my enjoyment of exploring the original sources. I have tried to provide the references to those sources wherever possible, and for the more recent developments I also provide references to various expository works as the occasion arises. For the pre-1950 results discussed here and their proofs, however, there is one canonical reference, which I give here once and for all: Antoni Zygmund's treatise [96]. (The more fundamental ones can also be found in Folland [29].) [ABSTRACT FROM AUTHOR]

This paper studies certain aspects of harmonic analysis on nonabelian free groups. We focus on the concept of a positive definite function on the free group and our primary goal is to understand how such functions can be extended from balls of finite radius to the entire group. Previous work showed that such extensions always exist and we study the problem of simultaneous extension of multiple positive definite functions. More specifically, we define a concept of ‘relative energy’ which measures the proximity between a pair of positive definite functions, and show that a pair of positive definite functions on a finite ball can be extended to the entire group without increasing their relative energy. The proof is analytic, involving differentiation of noncommutative Szegö parameters. [ABSTRACT FROM AUTHOR]

This paper presents the effect of dead time on active power transfer of the dual active bridge (DAB) and a novel mitigation technique for the same. The whole power range is categorized into five zones based on the switching instant link current direction and the modified active power expressions with effect of dead time are derived for each zone. The novel compensation method for dead time improves the performance of any general optimized techniques for DAB with extended phase shift. Firstly, the link current values at different switching instants are estimated using the mathematical expressions obtained using a linear piece-wise method. Secondly, the values are used for compensation logic formulation in the whole power range. The compensation process is applied to two different configurations, open loop (circulating mode) and close loop (voltage control mode). The mid-power zone is compensated using a constant phase shift modification and the low power zone is compensated using a PI controller based phase shift modification. Finally, the effectiveness of the proposed compensation technique is verified through MATLAB Simulink model and 1.2 kW experimental prototype. [ABSTRACT FROM AUTHOR]

The paper presents the patterns of rainfall behavior brought out by the diagrams depicting the diurnal variation of SW monsoon rainfall at selected Indian stations. The stations in different geographical locations are found to exhibit different patterns of diurnal variation of rainfall. In general, coastal and island stations show enhanced rainfall from midnight to morning hours and below average rainfall during day time. Many inland stations show rainfall maximum towards afternoon / evening hours. Some hill stations show the same behavior as inland stations. However, at the heavy rainfall station of Cherrapunjee, the rainfall behavior is similar to that at the coastal stations. Possible physical mechanisms responsible for the diurnal variation of rainfall at stations under different categories, are briefly discussed. Harmonic analysis of hourly SW monsoon rainfall data of 33 stations show that for 19 stations, the first harmonic accounts for more than 50% of the variance of the rainfall series. These consist of (i) inland stations for which the maximum of the first harmonic, is reached between 16 hours IST and midnight, and (ii) coastal / island stations for which the maximum is seen between 03 and 07 hours IST. At most of the coastal and island stations, the first harmonic alone accounts for 75% or, more of the variance. For the heavy rainfall station of Cherrapunjee, the first harmonic which attains its maximum at 3.8 hours IST (∼4.4 hours LT), is able to account for 96% of the variance of the rainfall series. It is hoped that the information contained in this paper about the pattern of diurnal modulation of monsoon rainfall may serve as background material to monsoon precipitation climatology. [ABSTRACT FROM AUTHOR]

The voltage ripple and power loss in the DC-capacitor of a voltage source inverter depend on the harmonic currents flowing through the capacitor. This paper presents a double Fourier series based analysis of the harmonic contents of the DC capacitor current in a three-level neutral-point clamped (NPC) inverter, modulated with sine-triangle pulse-width modulation (SPWM) or conventional space vector pulse-width modulation (CSVPWM) schemes. The analytical results are validated experimentally on a 3-kVA three-level inverter prototype. The capacitor current in an NPC inverter has a periodicity of 120°at the fundamental or modulation frequency. Hence, this current contains third-harmonic and triplen-frequency components, apart from switching frequency components. The harmonic components vary with modulation index and power factor for both PWM schemes. The third harmonic current decreases with increase in modulation index and also decreases with increase in power factor in case of both PWM methods. In general, the third harmonic content is higher with SPWM than with CSVPWM at a given operating condition. Also, power loss and voltage ripple in the DC capacitor are estimated for both the schemes using the current harmonic spectrum and equivalent series resistance (ESR) of the capacitor. [ABSTRACT FROM AUTHOR]

The following collection of articles addresses one of the most basic problems in signal and image processing, namly the search for function systems (basis, frames, dictionaries) which allow efficient representations of certain classes of signals/images. Such representations are essential for decomposition and synthesis of signals, hence they are at the core of almost any application (coding, compression, pattern matching, feature extraction, classification, etc.) in this field. Accordingly, this is one of the best-studied topics in data analysis and a multitude of different concepts also addressing discretization/algorithmic issues has been investigated in this context. The starting point for reviving activities in this field was a recently rediscovered inconsistency in the concept of constructing optimally localized basis functions by minimizing uncertainty principles. In this short introductory note, we shortly sketch the basic dilemma, which was the starting point for this research approximately three years ago. However, the subsequent investigations presented in this collection of papers cover a much wider range of more general localization measures, discretization concepts as well as discussing algorithmic efficiency and stability. [ABSTRACT FROM AUTHOR]

In machining fixtures, minimizing workpiece deformation due to clamping and cutting forces is essential to maintain the machining accuracy. This can be achieved by selecting the optimal location of fixturing elements such as locators and clamps. Many researches in the past decades described more efficient algorithms for fixture layout optimization. In this paper, artificial neural networks (ANN)-based algorithm with design of experiments (DOE) is proposed to design an optimum fixture layout in order to reduce the maximum elastic deformation of the workpiece caused by the clamping and machining forces acting on the workpiece while machining. Finite element method (FEM) is used to find out the maximum deformation of the workpiece for various fixture layouts. ANN is used as an optimization tool to find the optimal location of the locators and clamps. To train the ANN, sufficient sets of input and output are fed to the ANN system. The input includes the position of the locators and clamps. The output includes the maximum deformation of the workpiece for the corresponding fixture layout under the machining condition. In the testing phase, the ANN results are compared with the FEM results. After the testing process, the trained ANN is used to predict the maximum deformation for the possible fixture layouts. DOE is introduced as another optimization tool to find the solution region for all design variables to minimum deformation of the work piece. The maximum deformations of all possible fixture layouts within the solution region are predicted by ANN. Finally, the layout which shows the minimum deformation is selected as optimal fixture layout. [ABSTRACT FROM AUTHOR]

The implementation of real-time corrosion-monitoring techniques can provide a reliable mechanism for detecting the overall effectiveness of chemical treatment programs and contribute to the selection and implementation of an adequate corrosion inhibitor system. Inadequate corrosion monitoring can result in an increase of both uniform and localized (pitting) corrosion activities which can lead to premature material failures. The present research was undertaken to ascertain whether linear polarization resistance (LPR), harmonic analysis (HA), and electrochemical noise (EN) in combination are suitable for the study of performance of corrosion inhibitors under a wide variety of conditions; for example, in the absence and the presence of hydrocarbons with or without the addition of corrosion inhibitors. The findings showed questionable results regarding the usefulness of the pitting factor derived from EN and HA data. In addition, statistical parameters were obtained, such as skew and kurtosis, and these results were compared with the pitting factor. [ABSTRACT FROM AUTHOR]

This paper presents a study on three types of finite element analyses of high power ultrasonic transducer by using the finite element commercial software called ANSYS. The transducer geometry was treated as a 2D axi- symmetric model, 3D quart and full 3D model. For all of the simulations the modeled transducer was used in modal analysis and harmonic solutions to understand its mechanical behavior and its natural frequency. A comparison was made between each type of modeling and experimental results. This comparison allows the parameters of FEM models to be iteratively adjusted and optimized and also leads to selection of the best modeling type. The achieved FEM results exhibited a remarkably high predictive potential of ANSYS in modeling and simulation and allowed control on the design and on the vibration behavior of the high power ultrasonic transducer. [ABSTRACT FROM AUTHOR]

In this paper, we obtain an analog of the Whittaker-Kotel’nikov-Shannon theorem on the basis of the harmonic Fourier-Bessel analysis. We construct a new interpolation formula for a class of entire functions of exponential type in which generalized Bessel translations are used instead of the usual translations. [ABSTRACT FROM AUTHOR]

Spectral leakage caused by synchronous error in a nonsynchronous sampling system is an important cause that reduces the accuracy of spectral analysis and harmonic measurement. This paper presents a software sampling frequency adaptive algorithm that can obtain the actual signal frequency more accurately, and then adjusts sampling interval base on the frequency calculated by software algorithm and modifies sampling frequency adaptively. It can reduce synchronous error and impact of spectral leakage; thereby improving the accuracy of spectral analysis and harmonic measurement for power system signal where frequency changes slowly. This algorithm has high precision just like the simulations show, and it can be a practical method in power system harmonic analysis since it can be implemented easily. [ABSTRACT FROM AUTHOR]

A novel hybrid control strategy for reducing torque ripple in permanent magnet brushless direct current motors has been developed by combining the deterministic nature of direct torque control and the adaptive nature of fuzzy logic control. Direct torque control using space vector pulse width modulation has been developed. This technique ensures the near-sinusoidal nature of the stator and rotor current. The impact of commutation ripple corresponding to the sinusoidal current is reduced compared to square wave current in conventional direct torque control. Further, the fuzzy logic controller provides adaptive modulation in space vector to mitigate the torque ripple. The response of the proposed method has been analyzed in the time domain as well as in the frequency domain. Experimental results establish a significant reduction in torque ripple and minimization of high-frequency components. A comparative study with conventional direct torque control methods has also been presented. [ABSTRACT FROM AUTHOR]

The harmonic response of a tuned wire/cylindrical monopole antenna has been determined in terms of its input impedance, VSWR, gain, and radiation patterns. The analysis on monopole antenna has been performed using two simulation tools; Numerical Electromagnetic Code (NEC) and CST microwave studios. The designed monopole antenna is mounted on an infinite ground plane using NEC creating an ideal scenario for simulation, whereas, more realistically, the monopole antenna is mounted on a finite ground plane using CST considering the practical requirements. A perfect conductor is used to design the monopole antenna as well as the ground plane. Simulated results using both the software are validated experimentally. The analysis establishes that the Electromagnetic Interference is efficiently radiated by monopole antenna at odd harmonics as the input impedance matching is good at these frequencies and also the gain is high. A mitigation technique without any additional circuitry has been proposed to suppress radiated off-band harmonics. The central idea behind the proposed mitigation technique is to create an input impedance mismatch at the interfering harmonic frequencies, which is achieved by increasing the diameter of the designed monopole antenna causing reduction in input impedance at higher harmonics. The increased diameter in terms of wavelength is still small at fundamental mode. Thus, the performance of the antenna at fundamental frequency remains largely unaffected, whereas, reflection co-efficient becomes very high at harmonics. [ABSTRACT FROM AUTHOR]

Simulation sensitivity analysis is an important problem for simulation practitioners analyzing complex systems. The significance of this problem has resulted in the development various gradient estimators that can be used to address this issue. Although higher derivative estimators have been discussed concurrently, less attention has been given assess the efficiency and feasibility of computing such estimators. In this paper, two second derivative estimators are presented. The first estimators, called the HFD estimators, combine harmonic gradient estimators with finite differences second derivative estimators. The resulting hybrid estimators require O(p) fewer simulation runs to implement compared the straightforward finite differences approach, where p is the number of input parameters in the simulation model. The second estimators, called the HA estimators, incorporate harmonic analysis directly, requiring one or two simulation runs to implement, depending whether a control variate simulation run is made. Expressions for the bias and the variance of the HFD and the HA estimators (with and without variance reduction techniques) are derived. Optimal mean squared error convergence rates are also discussed. particular, the convergence rates for both these estimators are shown to be the same, though the computational performance of the HFD estimators is better than that for the HA estimators on an M/M/l queue simulation model. Computational results for the HFD estimators on an (s, S) inventory system simulation model are also included. [ABSTRACT FROM AUTHOR]

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This paper considers regression tasks involving high-dimensional multivariate processes whose structure is dependent on some known graph topology. We put forth a new definition of time-vertex wide-sense stationarity, or joint stationarity for short, that goes beyond product graphs. Joint stationarity helps by reducing the estimation variance and recovery complexity. In particular, for any jointly stationary process (a) one reliably learns the covariance structure from as little as a single realization of the process and (b) solves MMSE recovery problems, such as interpolation and denoising, in computational time nearly linear on the number of edges and timesteps. Experiments with three datasets suggest that joint stationarity can yield accuracy improvements in the recovery of high-dimensional processes evolving over a graph, even when the latter is only approximately known, or the process is not strictly stationary. [ABSTRACT FROM AUTHOR]

Continual-clamp pulse width modulation (CCPWM) clamps each phase of a three-phase inverter to one of the two dc buses continually for 60∘ duration in each half of the fundamental cycle. Split-clamp pulse width modulation (SCPWM) divides the 60∘ clamping interval into two sub-intervals, which are not necessarily equal, and falling in two different quarter cycles. Whether continual clamp or split clamp, the positioning of the clamping interval in case of CCPWM, and the ratio of splitting the clamping interval in SCPWM - all influence the waveform quality of the inverter output. This paper derives analytically closed-form expressions for the total RMS harmonic distortion factor and torque ripple factor pertaining to CCPWM with any arbitrary position of the clamping interval (i.e., generalized CCPWM) and also corresponding to SCPWM with any arbitrary ratio of splitting of the clamping interval (i.e., generalized SCPWM). The analytical results are well supported by experimental results on 3-hp and 5-hp induction motor drives. [ABSTRACT FROM AUTHOR]

Heat transport through short and closed vegetation such as grass is modelled by a simple diffusion process. The grass is treated as a homogeneous 'sponge layer' with uniform thermal diffusivity and conductivity, placed on top of the soil. The temperature and heat-flux dynamics in both vegetation and soil are described using harmonic analysis. All thermal properties have been determined by optimization against observations from the Haarweg climatological station in The Netherlands. Our results indicate that both phase and amplitude of soil temperatures can be accurately reproduced from the vegetation surface temperature. The diffusion approach requires no specific tuning to, for example, the daily cycle, but instead responds to all frequencies present in the input data, including quick changes in cloud cover and day–night transitions. The newly determined heat flux at the atmosphere–vegetation interface is compared with the other components of the surface energy balance at this interface. The budget is well-closed, particularly in the most challenging cases with varying cloud cover and during transition periods. We conclude that the diffusion approach (either implemented analytically or numerically) is a physically consistent alternative to more ad hoc methods, like 'skin resistance' approaches for vegetation and bulk correction methods for upper soil heat storage. However, more work is needed to evaluate parameter variability and robustness under different climatological conditions. From a numerical perspective, the present representation of vegetation allows for both slow and rapid feedbacks between the atmosphere and the surface. As such, it would be interesting to couple the present surface parametrization to turbulence-resolving models, such as large-eddy simulations. [ABSTRACT FROM AUTHOR]

We define Hölder classes Λ α associated with a Markovian semigroup and prove that, when the semigroup satisfies the Γ 2 ≥ 0 condition, the Riesz transforms are bounded between the Hölder classes. As a consequence, this bound holds in manifolds with nonnegative Ricci curvature. We also show, without the need for extra assumptions on the semigroup, that a version of the Morrey inequalities is equivalent to the ultracontractivity property. This result extends the semigroup approach to the Sobolev inequalities laid by Varopoulos. After that, we study certain families of operators between the homogeneous Hölder classes. One of these families is given by analytic spectral multipliers and includes the imaginary powers of the generator, the other, by smooth multipliers analogous to those in the Marcienkiewicz theorem. Lastly, we explore the connection between the Hölder norm and Campanato's formula for semigroups. [ABSTRACT FROM AUTHOR]

We prove that with "high probability" a random Kostlan polynomial in n + 1 many variables and of degree d can be approximated by a polynomial of "low degree" without changing the topology of its zero set on the sphere S n . The dependence between the "low degree" of the approximation and the "high probability" is quantitative: for example, with overwhelming probability, the zero set of a Kostlan polynomial of degree d is isotopic to the zero set of a polynomial of degree O (d log d) . The proof is based on a probabilistic study of the size of C 1 -stable neighborhoods of Kostlan polynomials. As a corollary, we prove that certain topological types (e.g., curves with deep nests of ovals or hypersurfaces with rich topology) have exponentially small probability of appearing as zero sets of random Kostlan polynomials. [ABSTRACT FROM AUTHOR]

We show that integrability properties of integral transforms with kernel depending on the product of arguments (which include in particular, popular Laplace, Hankel, Mittag-Leffler transforms and various others) are better described in terms of Morrey spaces than in terms of Lebesgue spaces. Mapping properties of integral transforms of such a type in Lebesgue spaces, including weight setting, are known. We discover that local weighted Morrey and complementary Morrey spaces are very appropriate spaces for describing integrability properties of such transforms. More precisely, we show that under certain natural assumptions on the kernel, transforms under consideration act from local weighted Morrey space to a weighted complementary Morrey space and vice versa, where an interplay between behavior of functions and their transforms at the origin and infinity is transparent. In case of multidimensional integral transforms, for this goal we introduce and use anisotropic mixed norm Morrey and complementary Morrey spaces. MSC 2010: Primary 46E30, 42C20; Secondary 44A05, 44A10, 44A30 [ABSTRACT FROM AUTHOR]

Electrical power systems are becoming more susceptible to disturbances in the power grid such as harmonic distortions. The reason for this is the improvement of power in electronics, which allows for more efficient motor control and starting techniques through electronic converters. However, the use of these devices distorts the voltage and current waveform of the power system due to the harmonics injection. In the case of production platforms and drilling rigs, there are several motors that are fed by frequency converters. These facilities have a peculiarity that worsens the harmonics issues, which is the risk of resonance, consequently causing voltage peaks that can lead to equipment damage. The risk of resonance is due to the use of long submarine cables that in turn, because of the long distances, have considerable capacitance values that can resonate with the inductance from the inductive loads such as power transformers. The present work aims to evaluate a platform electrical system in terms of power quality considering the situation of resonance caused by a submarine power cable. Overviews of the electrical system and of the adopted submarine cable model will first be presented, and then, the results of the simulations are discussed. [ABSTRACT FROM AUTHOR]

The goal of the present study is to examine the applicability of non-destructive magnetic hysteresis loop technique and Hall effect sensor to characterize the strain induced α′-martensite in an austenitic stainless steel. For this purpose, eight different levels of tensile deformation, from 0.05 to 0.44 true stain values, were applied and corresponding induced martensite fractions were determined, using X-ray diffraction method. Finally, magnetic hysteresis loop and Hall effect methods were applied. Results show that major outputs of hysteresis loop (maximum flux density, retentivity and coercivity) and Hall effect (real part, imaginary part, modulus and phase angle for the 3rd harmonic) are significantly affected by variations in the induced martensite fraction. Besides, a new parameter, amplitude and shape of raw received signal, was used in this study. The established relationships with high correlation coefficients between electromagnetic outputs and martensite fraction indicate the potential of the proposed methods to be used for detecting the microstructural changes in AISI 304 stainless steel subjected to different strains. [ABSTRACT FROM AUTHOR]

In this study, we developed an aluminum-load-cell-based wireless Ringer's solution monitoring and alarm (WRMA) system. The Al load cell was designed with a rectangular shape, and the load was concentrated in the lower beam part of the load cell because of the anisotropic thickness. From the static analysis, we identified the appropriate location for a Wheatstone bridge circuit consisting of four strain gauges. In addition, the modal and harmonic analyses showed that the vibrational frequencies of the hospital environment do not seriously interfere with the output voltage of the Al load cell. However, random vibrations generated by the movement of the WRMA system on various surfaces severely increase the standard deviation of the measured solution weight by ± 10 g or more. Such vibrational error is too large because the average weight of Ringer's solution is 30–40 g at the time of replacing Ringer's solution. Thus, this error could be confusing for nurses and result in mistakes in the timely replacement of the Ringer's solution. However, the standard deviation of the measured weight was dramatically reduced to ± 3 g or less by using the vibration correction algorithm developed in the present study. [ABSTRACT FROM AUTHOR]

This work analyzes the behavior of surface-mounted permanent magnet synchronous motors (SPMSMs) operating under stator faults. The studied faults are resistive unbalance and winding inter-turn short circuits, which may lead to unbalanced conditions of the motor. Both faults may reduce motor efficiency and performance and produce premature ageing. This work develops an analytical model of the motor when operating under stator faults. By this way, the theoretical basis to understand the effects of resistive unbalance and stator winding inter-turn faults in SPMSMs is settled. This work also compares two methods for detecting and discriminating both faults. For this purpose, a method based on the analysis of the zero-sequence voltage component is presented, which is compared to the traditional method, i.e. the analysis of the stator currents harmonics. Both simulation and experimental results presented in this work show the potential of the zero-sequence voltage component method to provide helpful and reliable data to carry out a simultaneous diagnosis of resistive unbalance and stator winding inter-turn faults. [ABSTRACT FROM AUTHOR]

Asymptotic representations of power bounded operators and bounded semigroups of linear operators acting in Banach spaces are obtained under the assumptions that the spectrum of bounded operators on the unit circle and the spectrum of the semigroup generator on the imaginary axis are countable. The methods of abstract harmonic analysis and the spectral theory of operators were used. [ABSTRACT FROM AUTHOR]

We prove the complete monotonicity on $${(0, \infty)^{n}}$$ for suitable inverse powers of the spanning-tree polynomials of graphs and, more generally, of the basis generating polynomials of certain classes of matroids. This generalizes a result of Szegő and answers, among other things, a long-standing question of Lewy and Askey concerning the positivity of Taylor coefficients for certain rational functions. Our proofs are based on two ab-initio methods for proving that $${P^{-\beta}}$$ is completely monotone on a convex cone C: the determinantal method and the quadratic-form method. These methods are closely connected with harmonic analysis on Euclidean Jordan algebras (or equivalently on symmetric cones). We furthermore have a variety of constructions that, given such polynomials, can create other ones with the same property: among these are algebraic analogues of the matroid operations of deletion, contraction, direct sum, parallel connection, series connection and 2-sum. The complete monotonicity of $${P^{-\beta}}$$ for some $${\beta > 0}$$ can be viewed as a strong quantitative version of the half-plane property (Hurwitz stability) for P, and is also related to the Rayleigh property for matroids. [ABSTRACT FROM AUTHOR]

We consider the spaces A( $\mathbb{T}^m $) of functions f on the m-dimensional torus $\mathbb{T}^m $ such that the sequence of Fourier coefficients $\hat f = \{ \hat f(k),k \in \mathbb{Z}^m \} $ belongs to l(ℤ), 1 ≤ p < 2. The norm on A( $\mathbb{T}^m $) is defined by $\left\| f \right\|_{A_p (\mathbb{T}^m )} = \left\| {\hat f} \right\|_{l^p (\mathbb{Z}^m )} $. We study the rate of growth of the norms $\left\| {e^{i\lambda \phi } } \right\|_{A_p (\mathbb{T}^m )} $ as |λ| → ∞, λ ∈ ℝ, for C-smooth real functions φ on $\mathbb{T}^m $ (the one-dimensional case was investigated by the author earlier). The lower estimates that we obtain have direct analogs for the spaces A(ℝ). [ABSTRACT FROM AUTHOR]

We present a novel approach for the estimation of 3D-motion directly from two images using the Radon transform. The feasibility of any camera motion is computed by integrating over all feature pairs that satisfy the epipolar constraint. This integration is equivalent to taking the inner product of a similarity function on feature pairs with a Dirac function embedding the epipolar constraint. The maxima in this five dimensional motion space will correspond to compatible rigid motions. The main novelty is in the realization that the Radon transform is a filtering operator: If we assume that the similarity and Dirac functions are defined on spheres and the epipolar constraint is a group action of rotations on spheres, then the Radon transform is a correlation integral. We propose a new algorithm to compute this integral from the spherical Fourier transform of the similarity and Dirac functions. Generating the similarity function now becomes a preprocessing step which reduces the complexity of the Radon computation by a factor equal to the number of feature pairs processed. The strength of the algorithm is in avoiding a commitment to correspondences, thus being robust to erroneous feature detection, outliers, and multiple motions. [ABSTRACT FROM AUTHOR]