
Interpolating Spherical Harmonics for Computing Antenna Patterns
20110701
the specific radontransform algorithms of ISAR. 28 References [1] Arfken , George [1970] Mathematical Methods for Physicists, second edi tion...approximation methods . Section 2 sets out two antenna patterns to be tested in the spline algorithm. Section 3 reviews the spherical harmonic functions Y mn...number of samples on the sphere [12]. This compressed sensing result will not reduce the method of moment computations. All the current must be

Harmonic analysis of Doubly Fed Induction Generators
Lindholm, Morten; Rasmussen, Tonny Wederberg
20030101
This paper gives an overview of the frequency spectrum of the stator and rotor currents in a doubly fed induction generator (DFIG) used in wind power applications. The paper also presents a method to eliminate higher harmonics and interharmonics in the DFIG stator current. The method is implemented...... on a 40 kW laboratory model connected to the utilitygrid, where the DFIG is supplied by a backtoback 3level NPCconverter....

Curvature and bubble convergence of harmonic maps
Kokarev, Gerasim
20100101
We explore geometric aspects of bubble convergence for harmonic maps. More precisely, we show that the formation of bubbles is characterised by the local excess of curvature on the target manifold. We give a universal estimate for curvature concentration masses at each bubble point and show that there is no curvature loss in the necks. Our principal hypothesis is that the target manifold is Kaehler.

Rotating field transformers eliminate rectifier harmonics
Pastor, C.E. [Westinghouse Motor Co., Round Rock, TX (United States); Buckle, K.A. [Univ. of South Florida, Tampa, FL (United States); Luce, J.W. [Luce (John W.), Tampa, FL (United States)
19951001
The rotating field transformer is a static device that has the same magnetic field as a three phase motor. When used to feed diode rectifiers, it converts ac to dc with low ripple on the output voltage and remarkably low current distortion on the input. Filters are not needed. This is a timely development because it is an economical and very effective solution to the growing problem of power system harmonics.

Harmonic Resonances in Wind Power Plants
Fernandez, Francisco Daniel Freijedo; Chaudhary, Sanjay; Teodorescu, Remus
20150101
converters. Subsequently, pros and cons of frequency and time domain analysis methods are outlined. The next sections are devoted to mitigation methods implemented in the power electronics converters. From the wind turbine perspective, different techniques to enhance the robustness of the controller...... are analyzed. Subsequently, the suitability for active damping of harmonics using STATCOM devices is assessed, with focus both on control techniques and power converter technologies....

Fischer decomposition in symplectic harmonic analysis
Brackx, Fred; De Schepper, Hennie; Eelbode, David; Lávička, Roman; Soucek, Vladimir
20140101
In the framework of quaternionic Clifford analysis in Euclidean space , which constitutes a refinement of Euclidean and Hermitian Clifford analysis, the Fischer decomposition of the space of complex valued polynomials is obtained in terms of spaces of socalled (adjoint) symplectic spherical harmonics, which are irreducible modules for the symplectic group Sp. Its Howe dual partner is determined to be sl(2, C) circle plus sl(2, C) = so(4, C).

Unitary representations and harmonic analysis an introduction
Sugiura, M
19900101
The principal aim of this book is to give an introduction to harmonic analysis and the theory of unitary representations of Lie groups. The second edition has been brought up to date with a number of textual changes in each of the five chapters, a new appendix on Fatou''s theorem has been added in connection with the limits of discrete series, and the bibliography has been tripled in length.

Food legislation and its harmonization in Russia.
Shamtsyan, Mark
20140801
Bringing Russian legislation into compliance with international norms and standards is necessary after its accession to the World Trade Organization. Harmonization of food legislation and of sanitary and phytosanitary measures are among the problems that had to be solved first. Many Russian food and trade regulations had been changed or are still in the process of being reformed, largely owing to a policy of integration pursued by the Customs Union of Russia, Belarus and Kazakhstan. However, as a member of the Eurasian Economic Community, Russia is also engaged not only in harmonization throughout the Customs Union but also Kirgizstan and Tajikistan, and Armenia, Moldova and Ukraine as observer countries. Russia also continues to coordinate policy reforms closely with the European Union, its primary trade partner, ultimately bringing Russian food and sanitary norms closer to international standards (e.g. Codex). Today, all participants in the Russian food production chain, processing and sale of foods have to deal with growing numbers of security standards. Many organizations are certified under several schemes, which leads to unnecessary costs. Harmonization of standards has helped promote solutions in the domestic market as well as importexport of foods and raw materials for production. Priorities have included food safety for human health, consumer protection, removal of hazardous and/or adulterated products and increased competition within the domestic food market as well as mutual recognition of certification in bilateral and multilateral (inter)national agreements. © 2013 Society of Chemical Industry.

Harmonics of circadian gene transcription in mammals.
Michael E Hughes
20090401
Full Text Available The circadian clock is a molecular and cellular oscillator found in most mammalian tissues that regulates rhythmic physiology and behavior. Numerous investigations have addressed the contribution of circadian rhythmicity to cellular, organ, and organismal physiology. We recently developed a method to look at transcriptional oscillations with unprecedented precision and accuracy using highdensity time sampling. Here, we report a comparison of oscillating transcription from mouse liver, NIH3T3, and U2OS cells. Several surprising observations resulted from this study, including a 100fold difference in the number of cycling transcripts in autonomous cellular models of the oscillator versus tissues harvested from intact mice. Strikingly, we found two clusters of genes that cycle at the second and third harmonic of circadian rhythmicity in liver, but not cultured cells. Validation experiments show that 12hour oscillatory transcripts occur in several other peripheral tissues as well including heart, kidney, and lungs. These harmonics are lost ex vivo, as well as under restricted feeding conditions. Taken in sum, these studies illustrate the importance of time sampling with respect to multiple testing, suggest caution in use of autonomous cellular models to study clock output, and demonstrate the existence of harmonics of circadian gene expression in the mouse.

Harmonics of circadian gene transcription in mammals.
Hughes, Michael E; DiTacchio, Luciano; Hayes, Kevin R; Vollmers, Christopher; Pulivarthy, S; Baggs, Julie E; Panda, Satchidananda; Hogenesch, John B
20090401
The circadian clock is a molecular and cellular oscillator found in most mammalian tissues that regulates rhythmic physiology and behavior. Numerous investigations have addressed the contribution of circadian rhythmicity to cellular, organ, and organismal physiology. We recently developed a method to look at transcriptional oscillations with unprecedented precision and accuracy using highdensity time sampling. Here, we report a comparison of oscillating transcription from mouse liver, NIH3T3, and U2OS cells. Several surprising observations resulted from this study, including a 100fold difference in the number of cycling transcripts in autonomous cellular models of the oscillator versus tissues harvested from intact mice. Strikingly, we found two clusters of genes that cycle at the second and third harmonic of circadian rhythmicity in liver, but not cultured cells. Validation experiments show that 12hour oscillatory transcripts occur in several other peripheral tissues as well including heart, kidney, and lungs. These harmonics are lost ex vivo, as well as under restricted feeding conditions. Taken in sum, these studies illustrate the importance of time sampling with respect to multiple testing, suggest caution in use of autonomous cellular models to study clock output, and demonstrate the existence of harmonics of circadian gene expression in the mouse.

Means of Harmonization in Religious Discourse
Irina Ščukina
20121201
Full Text Available Means of harmonization of religious discourse are considered by studying communicational behaviour (verbal and nonverbal between the religion institution and believers. The following factors defining specificity of realization of harmonization in Orthodox and other religious texts are taken into account: the communication channel between the author and the reader, a defining speech genre, the command of language (communication code, and extralinguistic factors. It is shown that sharing the general social, historical and national experience, as well as a lexical overlapping of actors on both sides of the communication channel are the deciding elements of the harmonization process. The analysis also shows that usage of rational argumentation is more likely to lead to harmonisation in comparison to other rhetoric tools (i. e. affective ones or storytelling. Rational and unemotional sermonic discourse is perceived as a sign of respect (namely, for the listener's intelligence. Another successful and muchapplied way seems to be evoking a feeling of equality, unity and/or identity between clerics and their flocks.

Dynamical origin of near and belowthreshold harmonic generation of Cs in an intense midinfrared laser field
Li, PengCheng; Sheu, YaeLin; Laughlin, Cecil; Chu, ShihI.
20150501
Near and belowthreshold harmonic generation provides a potential approach to generate vacuumultraviolet frequency comb. However, the dynamical origin of in these lower harmonics is less understood and largely unexplored. Here we perform an ab initio quantum study of the near and belowthreshold harmonic generation of caesium (Cs) atoms in an intense 3,600nm midinfrared laser field. Combining with a synchrosqueezing transform of the quantum timefrequency spectrum and an extended semiclassical analysis, the roles of multiphoton and multiple rescattering trajectories on the near and belowthreshold harmonic generation processes are clarified. We find that the multiphotondominated trajectories only involve the electrons scattered off the higher part of the combined atomfield potential followed by the absorption of many photons in near and belowthreshold regime. Furthermore, only the nearresonant belowthreshold harmonic is exclusive to exhibit phase locked features. Our results shed light on the dynamic origin of the near and belowthreshold harmonic generation.

HVDCAC system interaction from AC harmonics. Volume 1. Harmonic impedance calculations. Final report
Breuer, G D; Chow, J H; Lindh, C B; Miller, N W; Numrich, F H; Price, W W; Turner, A E; Whitney, R R
19820901
Improved methods are needed to characterize ac system harmonic behavior for ac filter design for HVDC systems. The purpose of this General Electric Company RP1138 research is to evaluate the present filter design practice and to investigate methods for calculating system harmonic impedances. An overview of ac filter design for HVDC systems and a survey of literature related to filter design have been performed. Two methods for calculating system harmonic impedances have been investigated. In the measurement method, an instrumentation system for measuring system voltage and current has been assembled. Different schemes of using the measurements to calculate system harmonic impedances have been studied. In the analytical method, a procedure to include various operating conditions has been proposed. Computer programs for both methods have been prepared, and the results of the measurement and analytical methods analyzed. A conclusion of the project is that the measurement and analytical methods both provided reasonable results. There are correlations between the measured and analytical results for most harmonics, although there are discrepancies between the assumptions used in the two methods. A sensitivity approach has been proposed to further correlate the results. From the results of the analysis, it is recommended that both methods should be tested further. For the measurement method, more testing should be done to cover different system operating conditions. In the analytical method, more detailed models for representing system components should be studied. In addition, alternative statistical and sensitivity approaches should be attempted.

HVDCAC system interaction from AC harmonics. Volume 1. Harmonic impedance calculations. Final report
Breuer, G D; Chow, J H; Lindh, C B; Miller, N W; Numrich, F H; Price, W W; Turner, A E; Whitney, R R
19820901
Improved methods are needed to characterize ac system harmonic behavior for ac filter design for HVDC systems. The purpose of this General Electric Company RP1138 research is to evaluate the present filter design practice and to investigate methods for calculating system harmonic impedances. An overview of ac filter design for HVDC systems and a survey of literature related to filter design have been performed. Two methods for calculating system harmonic impedances have been investigated. In the measurement method, an instrumentation system for measuring system voltage and current has been assembled. Different schemes of using the measurements to calculate system harmonic impedances have been studied. In the analytical method, a procedure to include various operating conditions has been proposed. Computer programs for both methods have been prepared, and the results of the measurement and analytical methods analyzed. A conclusion of the project is that the measurement and analytical methods both provided reasonable results. There are correlations between the measured and analytical results for most harmonics, although there are discrepancies between the assumptions used in the two methods. A sensitivity approach has been proposed to further correlate the results. From the results of the analysis, it is recommended that both methods should be tested further. For the measurement method, more testing should be done to cover different system operating conditions. In the analytical method, more detailed models for representing system components should be studied. In addition, alternative statistical and sensitivity approaches should be attempted.

Harmonic balance approach to the periodic solutions of the (an)harmonic relativistic oscillator
Belendez, Augusto [Departamento de Fisica, Ingenieria de Sistemas y Teoria de la Senal, Universidad de Alicante, Apartado 99, E03080 Alicante (Spain)], Email: a.belendez@ua.es; Pascual, Carolina [Departamento de Fisica, Ingenieria de Sistemas y Teoria de la Senal, Universidad de Alicante, Apartado 99, E03080 Alicante (Spain)
20071119
The firstorder harmonic balance method via the first Fourier coefficient is used to construct two approximate frequencyamplitude relations for the relativistic oscillator for which the nonlinearity (anharmonicity) is a relativistic effect due to the time line dilation along the world line. Making a change of variable, a new nonlinear differential equation is obtained and two procedures are used to approximately solve this differential equation. In the first the differential equation is rewritten in a form that does not contain a squareroot expression, while in the second the differential equation is solved directly. The approximate frequency obtained using the second procedure is more accurate than the frequency obtained with the first due to the fact that, in the second procedure, application of the harmonic balance method produces an infinite set of harmonics, while in the first procedure only two harmonics are produced. Both approximate frequencies are valid for the complete range of oscillation amplitudes, and excellent agreement of the approximate frequencies with the exact one are demonstrated and discussed. The discrepancy between the firstorder approximate frequency obtained by means of the second procedure and the exact frequency never exceeds 1.6%. We also obtained the approximate frequency by applying the secondorder harmonic balance method and in this case the relative error is as low 0.31% for all the range of values of amplitude of oscillation A.

Imaging parameters on third harmonic transmit phasing for tissue harmonic generation.
Shen, CheChou; Wang, YuChun; Yeh, ChihKuang
20080601
In third harmonic (3f0) transmit phasing, transmit waveforms comprising fundamental (f0) signal and 3f0 signal are used to generate both frequencysum and frequencydifference components for manipulation of tissue harmonic amplitude. Nevertheless, the acoustic propagation of 3f0 transmit signal suffers from more severe attenuation and phase aberration than the f0 signal and hence degrades the performance of 3f0 transmit phasing. Besides, 3f0 transmit parameters such as aperture size and signal bandwidth are also influential in 3f0 transmit phasing. In this study, extensive simulations were performed to investigate the effects of these imaging parameters. Results indicate that the harmonic enhancement and suppression in 3f0 transmit phasing are compromised when the magnitude of frequencydifference component decreases in the presence of tissue attenuation and phase aberration. To compensate for the reduced frequencydifference component, a higher 3f0 transmit amplitude can be used. When the transmit parameters are concerned, a smaller 3f0 transmit aperture can provide more axially uniform harmonic enhancement and more effective suppression of harmonic amplitude. In addition, the spectral leakage signal also interferes with tissue harmonics and degrades the efficacy of 3f0 transmit phasing. Our results suggest that, in the method of 3f0 transmit phasing, the transmit amplitude, phase and aperture size of 3f0 signal should remain adjustable for optimization of clinical performance. Besides, multipulse sequences such as pulse inversion are also favorable for leakage removal in 3f0 transmit phasing.

Second Harmonic Generation in Scanning Probe Microscopy for Edge Localization
HU XiaoGen; LI YuHe; LIN HaoShan; WANG DongSheng; QI Xin
20110101
We present an approach of second harmonic generation for edge localization of nanoscale defects measurement,based on the impact of the oscillating tip on the sample that induces higher harmonics of the excitation frequency.The harmonic signals of tip motion are measured by the heterodyne interferornetry. The edge amplitude ratio for the edge characterization can be calculated by a mechanics model and the threshold of edge localization is experimentally determined by second harmonic profiles. This approach has been successfully utilized to measure the pitch of a standard sample. The results show that the second harmonic is sensitive to locating the edge of nanoscale defects with high accuracy.%@@ We present an approach of second harmonic generation for edge localization of nanoscale defects measurement,based on the impact of the oscillating tip on the sample that induces higher harmonics of the excitation frequency.The harmonic signals of tip motion are measured by the heterodyne interferometry.The edge amplitude ratio for the edge characterization can be calculated by a mechanics model and the threshold of edge localization is experimentally determined by second harmonic profiles.This approach has been successfully utilized to measure the pitch of a standard sample.The results show that the second harmonic is sensitive to locating the edge of nanoscale defects with high accuracy.

Influence of Harmonics in Laboratory due to Nonlinear Loads
Risnidar Chan
20120301
Full Text Available This research was focused on the customer’s side of the meter which is the effect of harmonics on a laboratory in Electrical System Engineering School at K.Wai Perlis. Harmonic currents in equipments can cause them to experience overheating and increased losses, while harmonic voltage produces magnetic fields rotating at a speed corresponding to the harmonic frequency. This also results in equipments heating, mechanical vibrations and noise, reduced efficiency, reduced life, and voltage stress on insulation of equipment windings. The loads in this research are computers, Compact Fluorescent Lamps CFLs, Air Conditions and printers,which all of the loads are harmonic significant The instrument to measure and monitoring is Fluke 435 Power Quality Analyzer. With the operation of varying nonlinear loads, the injected harmonic current magnitudes and phase angles vary in a random way. This research offers the advantage of providing the utility a wealth of information on the effects of harmonics in their equipments. This will subsequently make them aware of the causes of increased cost and reduced efficiency that may be experienced by using these equipments. This paper describes the investigation cost of harmonic effect as THD, and harmonic energy losses cost. Keywords: harmonics, nonlinear loads, Energy losses cost, THD.

The sheath effect on the floating harmonic method
Lee, Jaewon; Kim, KyungHyun; Chung, ChinWook, Email: joykang@hanyang.ac.kr [Department of Electrical Engineering, Hanyang University, 17 Haengdangdong, Seongdonggu, Seoul 133791 (Korea, Republic of)
20151215
The floating harmonic method biases sinusoidal voltage to a probe sheath, and as its response, harmonic currents can be obtained. These currents can be used to determine the plasma parameters. However, different shapes of probes have different shapes of sheaths that can affect the diagnostic results. However, no research has been done on the sheath effect on the floating harmonic method. Therefore, we investigate the effect of the sheath during floating harmonic diagnostics by comparing cylindrical and planar probes. While the sinusoidal voltages were applied to a probe, because the sheath oscillated, the time variant ion current and their harmonic currents were added to the electron harmonic currents. In the floating harmonic method, the harmonic currents are composed of only the electron harmonic currents. Therefore, the ion harmonic currents affect the diagnostic results. In particular, the electron temperature obtained by the small probe tip was higher than that of the large probe tip. This effect was exacerbated when the ratio of the probe tip radius to the sheath length was smaller.

Toward Rigorous Data Harmonization in Cancer Epidemiology Research: One Approach.
Rolland, Betsy; Reid, Suzanna; Stelling, Deanna; Warnick, Greg; Thornquist, Mark; Feng, Ziding; Potter, John D
20151215
Cancer epidemiologists have a long history of combining data sets in pooled analyses, often harmonizing heterogeneous data from multiple studies into 1 large data set. Although there are useful websites on data harmonization with recommendations and support, there is little research on best practices in data harmonization; each project conducts harmonization according to its own internal standards. The field would be greatly served by charting the process of data harmonization to enhance the quality of the harmonized data. Here, we describe the data harmonization process utilized at the Fred Hutchinson Cancer Research Center (Seattle, Washington) by the coordinating centers of several research projects. We describe a 6step harmonization process, including: 1) identification of questions the harmonized data set is required to answer; 2) identification of highlevel data concepts to answer those questions; 3) assessment of data availability for data concepts; 4) development of common data elements for each data concept; 5) mapping and transformation of individual data points to common data elements; and 6) qualitycontrol procedures. Our aim here is not to claim a "correct" way of doing data harmonization but to encourage others to describe their processes in order that we can begin to create rigorous approaches. We also propose a research agenda around this issue. © The Author 2015. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please email: journals.permissions@oup.com.