Operator Semigroups meet Complex Analysis, Harmonic Analysis and Mathematical Physics
Chill, Ralph; Tomilov, Yuri
2015-01-01
This proceedings volume originates from a conference held in Herrnhut in June 2013. It provides unique insights into the power of abstract methods and techniques in dealing successfully with numerous applications stemming from classical analysis and mathematical physics. The book features diverse topics in the area of operator semigroups, including partial differential equations, martingale and Hilbert transforms, Banach and von Neumann algebras, Schrödinger operators, maximal regularity and Fourier multipliers, interpolation, operator-theoretical problems (concerning generation, perturbation and dilation, for example), and various qualitative and quantitative Tauberian theorems with a focus on transfinite induction and magics of Cantor. The last fifteen years have seen the dawn of a new era for semigroup theory with the emphasis on applications of abstract results, often unexpected and far removed from traditional ones. The aim of the conference was to bring together prominent experts in the field of modern...
Helson, Henry
2010-01-01
This second edition has been enlarged and considerably rewritten. Among the new topics are infinite product spaces with applications to probability, disintegration of measures on product spaces, positive definite functions on the line, and additional information about Weyl's theorems on equidistribution. Topics that have continued from the first edition include Minkowski's theorem, measures with bounded powers, idempotent measures, spectral sets of bounded functions and a theorem of Szego, and the Wiener Tauberian theorem. Readers of the book should have studied the Lebesgue integral, the elementary theory of analytic and harmonic functions, and the basic theory of Banach spaces. The treatment is classical and as simple as possible. This is an instructional book, not a treatise. Mathematics students interested in analysis will find here what they need to know about Fourier analysis. Physicists and others can use the book as a reference for more advanced topics.
Wolff, Thomas H; Shubin, Carol
2003-01-01
This book demonstrates how harmonic analysis can provide penetrating insights into deep aspects of modern analysis. It is both an introduction to the subject as a whole and an overview of those branches of harmonic analysis that are relevant to the Kakeya conjecture. The usual background material is covered in the first few chapters: the Fourier transform, convolution, the inversion theorem, the uncertainty principle and the method of stationary phase. However, the choice of topics is highly selective, with emphasis on those frequently used in research inspired by the problems discussed in the later chapters. These include questions related to the restriction conjecture and the Kakeya conjecture, distance sets, and Fourier transforms of singular measures. These problems are diverse, but often interconnected; they all combine sophisticated Fourier analysis with intriguing links to other areas of mathematics and they continue to stimulate first-rate work. The book focuses on laying out a solid foundation for fu...
Harmonic and geometric analysis
Citti, Giovanna; Pérez, Carlos; Sarti, Alessandro; Zhong, Xiao
2015-01-01
This book presents an expanded version of four series of lectures delivered by the authors at the CRM. Harmonic analysis, understood in a broad sense, has a very wide interplay with partial differential equations and in particular with the theory of quasiconformal mappings and its applications. Some areas in which real analysis has been extremely influential are PDE's and geometric analysis. Their foundations and subsequent developments made extensive use of the Calderón–Zygmund theory, especially the Lp inequalities for Calderón–Zygmund operators (Beurling transform and Riesz transform, among others) and the theory of Muckenhoupt weights. The first chapter is an application of harmonic analysis and the Heisenberg group to understanding human vision, while the second and third chapters cover some of the main topics on linear and multilinear harmonic analysis. The last serves as a comprehensive introduction to a deep result from De Giorgi, Moser and Nash on the regularity of elliptic partial differen...
Symmetries in physics and harmonics
International Nuclear Information System (INIS)
Kolk, D.
2006-01-01
In this book the symmetries of elementary particles are described in relation to the rules of harmonics in music. The selection rules are described in connections with harmonic intervals. Also symmetry breaking is considered in this framework. (HSI)
Hyperspherical Harmonics and Their Physical Applications
DEFF Research Database (Denmark)
Avery, James Emil; Avery, John Scales
Hyperspherical harmonics are extremely useful in nuclear physics and reactive scattering theory. However, their use has been confined to specialists with very strong backgrounds in mathematics. This book aims to change the theory of hyperspherical harmonics from an esoteric field, mastered....... The book is accompanied by programs and exercises designed for teaching and practical use....
Classical and multilinear harmonic analysis
Muscalu, Camil
2013-01-01
This two-volume text in harmonic analysis introduces a wealth of analytical results and techniques. It is largely self-contained and useful to graduates and researchers in pure and applied analysis. Numerous exercises and problems make the text suitable for self-study and the classroom alike. The first volume starts with classical one-dimensional topics: Fourier series; harmonic functions; Hilbert transform. Then the higher-dimensional Calderón-Zygmund and Littlewood-Paley theories are developed. Probabilistic methods and their applications are discussed, as are applications of harmonic analysis to partial differential equations. The volume concludes with an introduction to the Weyl calculus. The second volume goes beyond the classical to the highly contemporary and focuses on multilinear aspects of harmonic analysis: the bilinear Hilbert transform; Coifman-Meyer theory; Carleson's resolution of the Lusin conjecture; Calderón's commutators and the Cauchy integral on Lipschitz curves. The material in this vo...
Introduction to abstract harmonic analysis
Loomis, Lynn H
2011-01-01
Written by a prominent figure in the field of harmonic analysis, this classic monograph is geared toward advanced undergraduates and graduate students and focuses on methods related to Gelfand's theory of Banach algebra. 1953 edition.
Elements of abstract harmonic analysis
Bachman, George
2013-01-01
Elements of Abstract Harmonic Analysis provides an introduction to the fundamental concepts and basic theorems of abstract harmonic analysis. In order to give a reasonably complete and self-contained introduction to the subject, most of the proofs have been presented in great detail thereby making the development understandable to a very wide audience. Exercises have been supplied at the end of each chapter. Some of these are meant to extend the theory slightly while others should serve to test the reader's understanding of the material presented. The first chapter and part of the second give
Hyperspherical Harmonics and Their Physical Applications
DEFF Research Database (Denmark)
Avery, James Emil; Avery, John Scales
Hyperspherical harmonics are extremely useful in nuclear physics and reactive scattering theory. However, their use has been confined to specialists with very strong backgrounds in mathematics. This book aims to change the theory of hyperspherical harmonics from an esoteric field, mastered...... by specialists, into an easily-used tool with a place in the working kit of all theoretical physicists, theoretical chemists and mathematicians. The theory presented here is accessible without the knowledge of Lie-groups and representation theory, and can be understood with an ordinary knowledge of calculus...
Representation Discovery using Harmonic Analysis
Mahadevan, Sridhar
2008-01-01
Representations are at the heart of artificial intelligence (AI). This book is devoted to the problem of representation discovery: how can an intelligent system construct representations from its experience? Representation discovery re-parameterizes the state space - prior to the application of information retrieval, machine learning, or optimization techniques - facilitating later inference processes by constructing new task-specific bases adapted to the state space geometry. This book presents a general approach to representation discovery using the framework of harmonic analysis, in particu
Complex harmonic modal analysis of rotor systems
International Nuclear Information System (INIS)
Han, Dong Ju
2015-01-01
Complex harmonic analysis for rotor systems has been proposed from the strict complex modal analysis based upon Floquet theory. In this process the harmonic balance method is adopted, effectively associated with conventional eigenvalue analysis. Also, the harmonic coefficients equivalent to dFRFs in harmonic mode has been derived in practice. The modes are classified from identifying the modal characteristics, and the adaptation of harmonic balance method has been proven by comparing the results of the stability analyses from Floque theory and the eigen analysis. The modal features of each critical speed are depicted in quantitatively and qualitatively by showing that the strengths of each component of the harmonic coefficients are estimated from the order of magnitude analysis according to their harmonic patterns. This effectiveness has been verified by comparing with the numerical solutions
Pairwise harmonics for shape analysis
Zheng, Youyi
2013-07-01
This paper introduces a simple yet effective shape analysis mechanism for geometry processing. Unlike traditional shape analysis techniques which compute descriptors per surface point up to certain neighborhoods, we introduce a shape analysis framework in which the descriptors are based on pairs of surface points. Such a pairwise analysis approach leads to a new class of shape descriptors that are more global, discriminative, and can effectively capture the variations in the underlying geometry. Specifically, we introduce new shape descriptors based on the isocurves of harmonic functions whose global maximum and minimum occur at the point pair. We show that these shape descriptors can infer shape structures and consistently lead to simpler and more efficient algorithms than the state-of-the-art methods for three applications: intrinsic reflectional symmetry axis computation, matching shape extremities, and simultaneous surface segmentation and skeletonization. © 2012 IEEE.
Harmonic and complex analysis in several variables
Krantz, Steven G
2017-01-01
Authored by a ranking authority in harmonic analysis of several complex variables, this book embodies a state-of-the-art entrée at the intersection of two important fields of research: complex analysis and harmonic analysis. Written with the graduate student in mind, it is assumed that the reader has familiarity with the basics of complex analysis of one and several complex variables as well as with real and functional analysis. The monograph is largely self-contained and develops the harmonic analysis of several complex variables from the first principles. The text includes copious examples, explanations, an exhaustive bibliography for further reading, and figures that illustrate the geometric nature of the subject. Each chapter ends with an exercise set. Additionally, each chapter begins with a prologue, introducing the reader to the subject matter that follows; capsules presented in each section give perspective and a spirited launch to the segment; preludes help put ideas into context. Mathematicians and...
Physics of tissue harmonic imaging by ultrasound
Jing, Yuan
Tissue Harmonic Imaging (THI) is an imaging modality that is currently deployed on diagnostic ultrasound scanners. In THI the amplitude of the ultrasonic pulse that is used to probe the tissue is large enough that the pulse undergoes nonlinear distortion as it propagates into the tissue. One result of the distortion is that as the pulse propagates energy is shifted from the fundamental frequency of the source pulse into its higher harmonics. These harmonics will scatter off objects in the tissue and images formed from the scattered higher harmonics are considered to have superior quality to the images formed from the fundamental frequency. Processes that have been suggested as possibly responsible for the improved imaging in THI include: (1) reduced sensitivity to reverberation, (2) reduced sensitivity to aberration, and (3) reduction in side lobes. By using a combination of controlled experiments and numerical simulations, these three reasons have been investigated. A single element transducer and a clinical ultrasound scanner with a phased array transducer were used to image a commercial tissue-mimicking phantom with calibrated targets. The higher image quality achieved with THI was quantified in terms of spatial resolution and "clutter" signals. A three-dimensional model of the forward propagation of nonlinear sound beams in media with arbitrary spatial properties (a generalized KZK equation) was developed. A time-domain code for solving the KZK equation was validated with measurements of the acoustic field generated by the single element transducer and the phased array transducer. The code was used to investigate the impact of aberration using tissue-like media with three-dimensional variations in all acoustic properties. The three-dimensional maps of tissue properties were derived from the datasets available through the Visible Female project. The experiments and simulations demonstrated that second harmonic imaging (1) suffers less clutter associated with
Harmonic analysis from Fourier to wavelets
Pereyra, Maria Cristina
2012-01-01
In the last 200 years, harmonic analysis has been one of the most influential bodies of mathematical ideas, having been exceptionally significant both in its theoretical implications and in its enormous range of applicability throughout mathematics, science, and engineering. In this book, the authors convey the remarkable beauty and applicability of the ideas that have grown from Fourier theory. They present for an advanced undergraduate and beginning graduate student audience the basics of harmonic analysis, from Fourier's study of the heat equation, and the decomposition of functions into sums of cosines and sines (frequency analysis), to dyadic harmonic analysis, and the decomposition of functions into a Haar basis (time localization). While concentrating on the Fourier and Haar cases, the book touches on aspects of the world that lies between these two different ways of decomposing functions: time-frequency analysis (wavelets). Both finite and continuous perspectives are presented, allowing for the introd...
Harmonic analysis on symmetric spaces
Terras, Audrey
This text explores the geometry and analysis of higher rank analogues of the symmetric spaces introduced in volume one. To illuminate both the parallels and differences of the higher rank theory, the space of positive matrices is treated in a manner mirroring that of the upper-half space in volume one. This concrete example furnishes motivation for the general theory of noncompact symmetric spaces, which is outlined in the final chapter. The book emphasizes motivation and comprehensibility, concrete examples and explicit computations (by pen and paper, and by computer), history, and, above all, applications in mathematics, statistics, physics, and engineering. The second edition includes new sections on Donald St. P. Richards’s central limit theorem for O(n)-invariant random variables on the symmetric space of GL(n, R), on random matrix theory, and on advances in the theory of automorphic forms on arithmetic groups.
Finite mode analysis through harmonic waveguides
Alieva, T.; Wolf, K.B.
2000-01-01
The mode analysis of signals in a multimodal shallow harmonic waveguide whose eigenfrequencies are equally spaced and finite can be performed by an optoelectronic device, of which the optical part uses the guide to sample the wave field at a number of sensors along its axis and the electronic part
Shedding new light on Gaussian harmonic analysis
Teuwen, J.J.B.
2016-01-01
This dissertation consists out of two rather disjoint parts. One part concerns some results on Gaussian harmonic analysis and the other on an optimization problem in optics. In the first part we study the Ornstein–Uhlenbeck process with respect to the Gaussian measure. We focus on two areas. One is
Data-Aware Retrodiction for Asynchronous Harmonic Measurement in a Cyber-Physical Energy System
Liu, Youda; Wang, Xue; Liu, Yanchi; Cui, Sujin
2016-01-01
Cyber-physical energy systems provide a networked solution for safety, reliability and efficiency problems in smart grids. On the demand side, the secure and trustworthy energy supply requires real-time supervising and online power quality assessing. Harmonics measurement is necessary in power quality evaluation. However, under the large-scale distributed metering architecture, harmonic measurement faces the out-of-sequence measurement (OOSM) problem, which is the result of latencies in sensing or the communication process and brings deviations in data fusion. This paper depicts a distributed measurement network for large-scale asynchronous harmonic analysis and exploits a nonlinear autoregressive model with exogenous inputs (NARX) network to reorder the out-of-sequence measuring data. The NARX network gets the characteristics of the electrical harmonics from practical data rather than the kinematic equations. Thus, the data-aware network approximates the behavior of the practical electrical parameter with real-time data and improves the retrodiction accuracy. Theoretical analysis demonstrates that the data-aware method maintains a reasonable consumption of computing resources. Experiments on a practical testbed of a cyber-physical system are implemented, and harmonic measurement and analysis accuracy are adopted to evaluate the measuring mechanism under a distributed metering network. Results demonstrate an improvement of the harmonics analysis precision and validate the asynchronous measuring method in cyber-physical energy systems. PMID:27548171
Harmonic analysis on triple spaces
DEFF Research Database (Denmark)
Danielsen, Thomas Hjortgaard
In this thesis we study examples of triple spaces, both their structure theory, their invariant differential operators as well as analysis on them. The first major results provide us with some examples of triple spaces which are strongly spherical, i.e. satisfy some conditions reminiscent...
Harmonic Analysis and Group Representation
Figa-Talamanca, Alessandro
2011-01-01
This title includes: Lectures - A. Auslander, R. Tolimeri - Nilpotent groups and abelian varieties, M Cowling - Unitary and uniformly bounded representations of some simple Lie groups, M. Duflo - Construction de representations unitaires d'un groupe de Lie, R. Howe - On a notion of rank for unitary representations of the classical groups, V.S. Varadarajan - Eigenfunction expansions of semisimple Lie groups, and R. Zimmer - Ergodic theory, group representations and rigidity; and, Seminars - A. Koranyi - Some applications of Gelfand pairs in classical analysis.
Three-Phase Harmonic Analysis Method for Unbalanced Distribution Systems
Directory of Open Access Journals (Sweden)
Jen-Hao Teng
2014-01-01
Full Text Available Due to the unbalanced features of distribution systems, a three-phase harmonic analysis method is essential to accurately analyze the harmonic impact on distribution systems. Moreover, harmonic analysis is the basic tool for harmonic filter design and harmonic resonance mitigation; therefore, the computational performance should also be efficient. An accurate and efficient three-phase harmonic analysis method for unbalanced distribution systems is proposed in this paper. The variations of bus voltages, bus current injections and branch currents affected by harmonic current injections can be analyzed by two relationship matrices developed from the topological characteristics of distribution systems. Some useful formulas are then derived to solve the three-phase harmonic propagation problem. After the harmonic propagation for each harmonic order is calculated, the total harmonic distortion (THD for bus voltages can be calculated accordingly. The proposed method has better computational performance, since the time-consuming full admittance matrix inverse employed by the commonly-used harmonic analysis methods is not necessary in the solution procedure. In addition, the proposed method can provide novel viewpoints in calculating the branch currents and bus voltages under harmonic pollution which are vital for harmonic filter design. Test results demonstrate the effectiveness and efficiency of the proposed method.
Harmonic analysis of the precipitation in Greece
Nastos, P. T.; Zerefos, C. S.
2009-04-01
Greece is a country with a big variety of climates due to its geographical position, to the many mountain ranges and also to the multifarious and long coastline. The mountainous volumes are of such orientation that influences the distribution of the precipitation, having as a result, Western Greece to present great differentiations from Central and Eastern Greece. The application of harmonic analysis to the annual variability of precipitation is the goal of this study, so that the components, which compose the annual variability, be elicited. For this purpose, the mean monthly precipitation data from 30 meteorological stations of National Meteorological Service were used for the time period 1950-2000. The initial target is to reduce the number of variables and to detect structure in the relationships between variables. The most commonly used technique for this purpose is the application of Factor Analysis to a table having as columns the meteorological stations-variables and rows the monthly mean precipitation, so that 2 main factors were calculated, which explain the 98% of total variability of precipitation in Greece. Factor 1, representing the so-called uniform field and interpreting the most of the total variance, refers in fact to the Mediterranean depressions, affecting mainly the West of Greece and also the East Aegean and the Asia Minor coasts. In the process, the Fourier Analysis was applied to the factor scores extracted from the Factor Analysis, so that 2 harmonic components are resulted, which explain above the 98% of the total variability of each main factor, and are due to different synoptic and thermodynamic processes associated with Greece's precipitation construction. Finally, the calculation of the time of occurrence of the maximum precipitation, for each harmonic component of each one of the two main factors, gives the spatial distribution of appearance of the maximum precipitation in the Hellenic region.
Directory of Open Access Journals (Sweden)
Halimatus Sa’diyah
2017-12-01
Full Text Available The purpose of this research is to analyze of students' difficulties on the material elasticity and harmonic oscillation in the inquiry-based physics learning. It has eight stages. They are the orientation, the problem formulation, the formulation of hypotheses, the data obtaining, the testing hypotheses, conclusions, the implementation of the conclusions and generalizations, and the reflection stage. This research determines the student's learning difficulties on the each stage. The subject of this research is all of the students in X IPA 4 SMA N Sambungmacan Sragen. The amount of this research subject is thirty students. The method used in this research is descriptive qualitative. The data acquired with the learning process observation, the student's response questionnaire, and the student's cognitive tests. The results show that the student has difficulty in analyzing the elasticity and the force of deviation, speed, and acceleration concept, illustrates hooke law, and the matter's modulus elasticity. The difficult stages of the inquiry-based physics learning are the problem formulation, the formulation of hypotheses, the data obtaining, the testing hypotheses, conclusions, the implementation of the conclusions and generalizations, and the reflection stage.
Input Harmonic Analysis on the Slim DC-Link Drive Using Harmonic State Space Model
DEFF Research Database (Denmark)
Yang, Feng; Kwon, Jun Bum; Wang, Xiongfei
2017-01-01
The harmonic performance of the slim dc-link adjustable speed drives has shown good performance in some studies but poor in some others. The contradiction indicates that a feasible theoretical analysis is still lacking to characterize the harmonic distortion for the slim dc-link drive. Considerin...... results of the slim dc-link drive, loaded up to 2.0 kW, are presented to validate the theoretical analysis....... variation according to the switching instant, the harmonics at the steady-state condition, as well as the coupling between the multiple harmonic impedances. By using this model, the impaction on the harmonics performance by the film capacitor and the grid inductance is derived. Simulation and experimental...
Harmonic Interaction Analysis in Grid Connected Converter using Harmonic State Space (HSS) Modeling
DEFF Research Database (Denmark)
Kwon, Jun Bum; Wang, Xiongfei; Bak, Claus Leth
2015-01-01
-model, are introduced to analyze these problems. However, it is found that Linear Time Invariant (LTI) base model analysis makes it difficult to analyze these phenomenon because of time varying system operation trajectories, varying output impedance seen by grid connected systems and neglected switching component......An increasing number of power electronics based Distributed Generation (DG) systems and loads generate coupled harmonic as well as non-characteristic harmonic with each other. Several methods like impedance based analysis, which is derived from conventional small signal- and average...... during the modeling process. This paper investigates grid connected converter by means of Harmonic State Space (HSS) small signal model, which is modeled from Linear Time varying Periodically (LTP) system. Further, a grid connected converter harmonic matrix is investigated to analyze the harmonic...
Harmonic Interaction Analysis in Grid-connected Converter using Harmonic State Space (HSS) Modeling
DEFF Research Database (Denmark)
Kwon, Jun Bum; Wang, Xiongfei; Blaabjerg, Frede
2017-01-01
research about the harmonic interaction. However, it is found that the Linear Time Invariant (LTI) based model analysis makes it difficult to analyze these phenomena because of the time-varying properties of the power electronic based systems. This paper investigates grid-connected converter by using......An increasing number of power electronic based Distributed Generation (DG) systems and loads generate not only characteristic harmonics but also unexpected harmonics. Several methods like impedance based analysis, which are derived from the conventional average model, are introduced to perform...
Harmonic analysis on exponential solvable Lie groups
Fujiwara, Hidenori
2015-01-01
This book is the first one that brings together recent results on the harmonic analysis of exponential solvable Lie groups. There still are many interesting open problems, and the book contributes to the future progress of this research field. As well, various related topics are presented to motivate young researchers. The orbit method invented by Kirillov is applied to study basic problems in the analysis on exponential solvable Lie groups. This method tells us that the unitary dual of these groups is realized as the space of their coadjoint orbits. This fact is established using the Mackey theory for induced representations, and that mechanism is explained first. One of the fundamental problems in the representation theory is the irreducible decomposition of induced or restricted representations. Therefore, these decompositions are studied in detail before proceeding to various related problems: the multiplicity formula, Plancherel formulas, intertwining operators, Frobenius reciprocity, and associated alge...
Harmonic currents circulation in electrical networks simulation and analysis
Energy Technology Data Exchange (ETDEWEB)
Em-Mamlouk, W.M. [MEP, Cairo (Egypt); El-Sharkawy, M.A. [Shams Univ., Cairo (Egypt). Dept. of Electrical Power and Machines; Mostafa, H.E. [Jazan Univ., Jazan (Saudi Arabia). Electrical Dept.
2009-07-01
A detailed harmonic flow analysis for a 13-bus balanced industrial distribution system was presented. The aim of the study was to determine the influence of harmonic sources in various branches of the system on voltage and current waveforms before disruptions to the utility supply system occurred. The current harmonic contents of an adjustable speed drive (ASD) were studied under various loading conditions. The test system was simulated using a standard study test system. Harmonic effects from multiple sources were investigated, and voltage distortion on the different buses was monitored. The study demonstrated that while the harmonic loads circulated harmonic currents in all system branches, no harmonic source was directly connected to the system buses. Many of the investigated cases exceeded allowable voltage total harmonic distortion and or current total harmonic distortion standards set by the Institute of Electrical and Electronic Engineers (IEEE). It was concluded that active harmonic filters should be used to prevent the effects of harmonic current circulation at different buses on neighbouring loads within a system. 8 refs., 11 tabs., 15 figs.
Harmonic analysis in integrated energy system based on compressed sensing
International Nuclear Information System (INIS)
Yang, Ting; Pen, Haibo; Wang, Dan; Wang, Zhaoxia
2016-01-01
Highlights: • We propose a harmonic/inter-harmonic analysis scheme with compressed sensing theory. • Property of sparseness of harmonic signal in electrical power system is proved. • The ratio formula of fundamental and harmonic components sparsity is presented. • Spectral Projected Gradient-Fundamental Filter reconstruction algorithm is proposed. • SPG-FF enhances the precision of harmonic detection and signal reconstruction. - Abstract: The advent of Integrated Energy Systems enabled various distributed energy to access the system through different power electronic devices. The development of this has made the harmonic environment more complex. It needs low complexity and high precision of harmonic detection and analysis methods to improve power quality. To solve the shortages of large data storage capacities and high complexity of compression in sampling under the Nyquist sampling framework, this research paper presents a harmonic analysis scheme based on compressed sensing theory. The proposed scheme enables the performance of the functions of compressive sampling, signal reconstruction and harmonic detection simultaneously. In the proposed scheme, the sparsity of the harmonic signals in the base of the Discrete Fourier Transform (DFT) is numerically calculated first. This is followed by providing a proof of the matching satisfaction of the necessary conditions for compressed sensing. The binary sparse measurement is then leveraged to reduce the storage space in the sampling unit in the proposed scheme. In the recovery process, the scheme proposed a novel reconstruction algorithm called the Spectral Projected Gradient with Fundamental Filter (SPG-FF) algorithm to enhance the reconstruction precision. One of the actual microgrid systems is used as simulation example. The results of the experiment shows that the proposed scheme effectively enhances the precision of harmonic and inter-harmonic detection with low computing complexity, and has good
Symmetries in physics and harmonics; Symmetrien in Physik und Harmonik
Energy Technology Data Exchange (ETDEWEB)
Kolk, D.
2006-07-01
In this book the symmetries of elementary particles are described in relation to the rules of harmonics in music. The selection rules are described in connections with harmonic intervals. Also symmetry breaking is considered in this framework. (HSI)
Harmonic Analysis and Active Filtering in Offshore Wind Power Plants
DEFF Research Database (Denmark)
Chaudhary, Sanjay Kumar; Freijedo Fernandez, Francisco Daniel; Guerrero, Josep M.
2015-01-01
Due to presence of long high voltage cable networks, and power transformers for the grid connection, the offshore wind power plants (OWPPs) are susceptible to harmonic distortion and resonances. The grid connection of OWPP should not cause the harmonic distortion beyond the permissible limits...... at the point of common coupling (PCC). The resonance conditions should be avoided in all cases. This paper describes the harmonic analysis techniques applied on an OWPP network model. A method is proposed to estimate the harmonic current compensation from a shunt-connected active power filter to mitigate...
Universal few-body physics in a harmonic trap
International Nuclear Information System (INIS)
Tolle, S.; Hammer, H.W.; Metsch, B.Ch.
2011-01-01
Few-body systems with resonant short-range interactions display universal properties that do not depend on the details of their structure or their interactions at short distances. In the three-body system, these properties include the existence of a geometric spectrum of three-body Efimov states and a discrete scaling symmetry. Similar universal properties appear in 4-body and possibly higher-body systems as well. We set up an effective theory for few-body systems in a harmonic trap and study the modification of universal physics for 3- and 4-particle systems in external confinement. In particular, we focus on systems where the Efimov effect can occur and investigate the dependence of the 4-body spectrum on the experimental tuning parameters. (authors)
The evolution of applied harmonic analysis models of the real world
Prestini, Elena
2016-01-01
A sweeping exploration of the development and far-reaching applications of harmonic analysis such as signal processing, digital music, optics, radio astronomy, crystallography, medical imaging, spectroscopy, and more. Featuring a wealth of illustrations, examples, and material not found in other harmonic analysis books, this unique monograph skillfully blends together historical narrative with scientific exposition to create a comprehensive yet accessible work. While only an understanding of calculus is required to appreciate it, there are more technical sections that will charm even specialists in harmonic analysis. From undergraduates to professional scientists, engineers, and mathematicians, there is something for everyone here. The second edition of The Evolution of Applied Harmonic Analysis contains a new chapter on atmospheric physics and climate change, making it more relevant for today’s audience. Praise for the first edition: "…can be thoroughly recommended to any reader who is curious about the ...
Harmonic analysis and suppression in hybrid wind & PV solar system
Gupta, Tripti; Namekar, Swapnil
2018-04-01
The growing demand of electricity has led to produce power through non-conventional source of energy such as solar energy, wind energy, hydro power, energy through biogas and biomass etc. Hybrid system is taken to complement the shortcoming of either sources of energy. The proposed system is grid connected hybrid wind and solar system. A 2.1 MW Doubly fed Induction Generator (DFIG) has been taken for analysis of wind farm whose rotor part is connected to two back-to-back converters. A 250 KW Photovoltaic (PV) array taken to analyze solar farm where inverter is required to convert power from DC to AC since electricity generated through solar PV is in the form of DC. Stability and reliability of the system is very important when the system is grid connected. Harmonics is the major Power quality issue which degrades the quality of power at load side. Harmonics in hybrid system arise through the use of power conversion unit. The other causes of harmonics are fluctuation in wind speed and solar irradiance. The power delivered to grid must be free from harmonics and within the limits specified by Indian grid codes. In proposed work, harmonic analysis of the hybrid system is performed in Electrical Transient Analysis program (ETAP) and single tuned harmonic filter is designed to maintain the utility grid harmonics within limits.
Gurgiolo, Chris; Vinas, Adolfo F.
2009-01-01
This paper presents a spherical harmonic analysis of the plasma velocity distribution function using high-angular, energy, and time resolution Cluster data obtained from the PEACE spectrometer instrument to demonstrate how this analysis models the particle distribution function and its moments and anisotropies. The results show that spherical harmonic analysis produced a robust physical representation model of the velocity distribution function, resolving the main features of the measured distributions. From the spherical harmonic analysis, a minimum set of nine spectral coefficients was obtained from which the moment (up to the heat flux), anisotropy, and asymmetry calculations of the velocity distribution function were obtained. The spherical harmonic method provides a potentially effective "compression" technique that can be easily carried out onboard a spacecraft to determine the moments and anisotropies of the particle velocity distribution function for any species. These calculations were implemented using three different approaches, namely, the standard traditional integration, the spherical harmonic (SPH) spectral coefficients integration, and the singular value decomposition (SVD) on the spherical harmonic methods. A comparison among the various methods shows that both SPH and SVD approaches provide remarkable agreement with the standard moment integration method.
Harmonic analysis of electrified railway based on improved HHT
Wang, Feng
2018-04-01
In this paper, the causes and harms of the current electric locomotive electrical system harmonics are firstly studied and analyzed. Based on the characteristics of the harmonics in the electrical system, the Hilbert-Huang transform method is introduced. Based on the in-depth analysis of the empirical mode decomposition method and the Hilbert transform method, the reasons and solutions to the endpoint effect and modal aliasing problem in the HHT method are explored. For the endpoint effect of HHT, this paper uses point-symmetric extension method to extend the collected data; In allusion to the modal aliasing problem, this paper uses the high frequency harmonic assistant method to preprocess the signal and gives the empirical formula of high frequency auxiliary harmonic. Finally, combining the suppression of HHT endpoint effect and modal aliasing problem, an improved HHT method is proposed and simulated by matlab. The simulation results show that the improved HHT is effective for the electric locomotive power supply system.
Gia, Quoc; Mayeli, Azita; Mhaskar, Hrushikesh; Zhou, Ding-Xuan
2017-01-01
The second of a two volume set on novel methods in harmonic analysis, this book draws on a number of original research and survey papers from well-known specialists detailing the latest innovations and recently discovered links between various fields. Along with many deep theoretical results, these volumes contain numerous applications to problems in signal processing, medical imaging, geodesy, statistics, and data science. The chapters within cover an impressive range of ideas from both traditional and modern harmonic analysis, such as: the Fourier transform, Shannon sampling, frames, wavelets, functions on Euclidean spaces, analysis on function spaces of Riemannian and sub-Riemannian manifolds, Fourier analysis on manifolds and Lie groups, analysis on combinatorial graphs, sheaves, co-sheaves, and persistent homologies on topological spaces. Volume II is organized around the theme of recent applications of harmonic analysis to function spaces, differential equations, and data science, covering topics such a...
Two dimensional kinetic analysis of electrostatic harmonic plasma waves
Energy Technology Data Exchange (ETDEWEB)
Fonseca-Pongutá, E. C.; Ziebell, L. F.; Gaelzer, R. [Instituto de Física, UFRGS, 91501-970 Porto Alegre, RS (Brazil); Yoon, P. H. [IPST, University of Maryland, College Park, Maryland 20742 (United States); SSR, Kyung Hee University, Yongin, Gyeonggi 446-701 (Korea, Republic of)
2016-06-15
Electrostatic harmonic Langmuir waves are virtual modes excited in weakly turbulent plasmas, first observed in early laboratory beam-plasma experiments as well as in rocket-borne active experiments in space. However, their unequivocal presence was confirmed through computer simulated experiments and subsequently theoretically explained. The peculiarity of harmonic Langmuir waves is that while their existence requires nonlinear response, their excitation mechanism and subsequent early time evolution are governed by essentially linear process. One of the unresolved theoretical issues regards the role of nonlinear wave-particle interaction process over longer evolution time period. Another outstanding issue is that existing theories for these modes are limited to one-dimensional space. The present paper carries out two dimensional theoretical analysis of fundamental and (first) harmonic Langmuir waves for the first time. The result shows that harmonic Langmuir wave is essentially governed by (quasi)linear process and that nonlinear wave-particle interaction plays no significant role in the time evolution of the wave spectrum. The numerical solutions of the two-dimensional wave spectra for fundamental and harmonic Langmuir waves are also found to be consistent with those obtained by direct particle-in-cell simulation method reported in the literature.
Harmonic analysis on local fields and adelic spaces. I
International Nuclear Information System (INIS)
Osipov, D V; Parshin, A N
2008-01-01
We develop harmonic analysis on the objects of a category C 2 of infinite-dimensional filtered vector spaces over a finite field. This category includes two-dimensional local fields and adelic spaces of algebraic surfaces defined over a finite field. As the main result, we construct the theory of the Fourier transform on these objects and obtain two-dimensional Poisson formulae
ANALYSIS OF HARMONIC INJECTION TO THE MODULATION OF ...
African Journals Online (AJOL)
2013-03-01
Mar 1, 2013 ... Abstract. This paper explores the analysis of third and ninth harmonic injection to the modulation of a multi- level diode clamped converter (DCC) at a varying modulation index. The spectral distributions of the various multi-level waveforms obtained under normal modulation index of 0.8 and over modulation ...
Harmonic Analysis Associated with the Generalized q-Bessel Operator
Directory of Open Access Journals (Sweden)
Ahmed Abouelaz
2016-01-01
Full Text Available In this article, we give a new harmonic analysis associated with the generalized q-Bessel operator. We introduce the generalized $q$-Bessel transform, the generalized q-Bessel translation and the generalized $q$-Bessel convolution product.
Harmonic Analysis of Offshore Wind Farms with Full Converter Wind Turbines
DEFF Research Database (Denmark)
Kocewiak, Lukasz Hubert; Hjerrild, Jesper; Bak, Claus Leth
2009-01-01
to a shore with a long HV cable. The way of propagation and effects of harmonics are presented for different study cases. Modeling strategies of harmonic sources for harmonic analysis are described and compared. Different results dependent on applied harmonic models are shown and discussed in this paper...
The influence of spring length on the physical parameters of simple harmonic motion
International Nuclear Information System (INIS)
Triana, C A; Fajardo, F
2012-01-01
The aim of this work is to analyse the influence of spring length on the simple harmonic motion of a spring-mass system. In particular, we study the effect of changing the spring length on the elastic constant k, the angular frequency ω and the damping factor γ of the oscillations. To characterize the behaviour of these variables we worked with a series of springs of seven different lengths, in which the elastic constant was found by means of the spring-elongation measurement and ω was obtained from the measurement of the oscillation period T of a suspended mass. The oscillatory movement was recorded using a force sensor and the γ value was determined by the fit of the envelope oscillations. Graphical analysis of the results shows that k, ω and γ decrease when the natural spring length increases. This experiment can be performed with equipment normally found in undergraduate physics laboratories. In addition, through graphical analysis students can deduce some relationships between variables that determine the simple harmonic motion behaviour. (paper)
Analysis on h-harmonics and Dunkl transforms
2015-01-01
As a unique case in this Advanced Courses book series, the authors have jointly written this introduction to h-harmonics and Dunkl transforms. These are extensions of the ordinary spherical harmonics and Fourier transforms, in which the usual Lebesgue measure is replaced by a reflection-invariant weighted measure. The theory, originally introduced by C. Dunkl, has been expanded on by many authors over the last 20 years. These notes provide an overview of what has been developed so far. The first chapter gives a brief recount of the basics of ordinary spherical harmonics and the Fourier transform. The Dunkl operators, the intertwining operators between partial derivatives and the Dunkl operators are introduced and discussed in the second chapter. The next three chapters are devoted to analysis on the sphere, and the final two chapters to the Dunkl transform. The authors’ focus is on the analysis side of both h-harmonics and Dunkl transforms. The need for background knowledge on reflection groups is kept to a...
DEFF Research Database (Denmark)
Kwon, Jun Bum; Wang, Xiongfei; Bak, Claus Leth
2015-01-01
The increasing number of renewable energy sources at the distribution grid is becoming a major issue for utility companies, since the grid connected converters are operating at different operating points due to the probabilistic characteristics of renewable energy. Besides, typically, the harmonics...... proposes a new model of a single phase grid connected renewable energy source using the Harmonic State Space modeling approach, which is able to identify such problems and the model can be extended to be applied in the multiple connected converter analysis. The modeling results show the different harmonic...... and impedance from other renewable energy sources are not taken carefully into account in the installation and design. However, this may bring an unknown harmonic instability into the multiple power sourced system and also make the analysis difficult due to the complexity of the grid network. This paper...
A note about Norbert Wiener and his contribution to Harmonic Analysis and Tauberian Theorems
Almira, J. M.; Romero, A. E.
2009-05-01
In this note we explain the main motivations Norbert Wiener had for the creation of his Generalized Harmonic Analysis [13] and his Tauberian Theorems [14]. Although these papers belong to the most pure mathematical tradition, they were deeply based on some Engineering and Physics Problems and Wiener was able to use them for such diverse areas as Optics, Brownian motion, Filter Theory, Prediction Theory and Cybernetics.
HARMONIC ANALYSIS OF SVPWM INVERTER USING MULTIPLE-PULSES METHOD
Directory of Open Access Journals (Sweden)
Mehmet YUMURTACI
2009-01-01
Full Text Available Space Vector Modulation (SVM technique is a popular and an important PWM technique for three phases voltage source inverter in the control of Induction Motor. In this study harmonic analysis of Space Vector PWM (SVPWM is investigated using multiple-pulses method. Multiple-Pulses method calculates the Fourier coefficients of individual positive and negative pulses of the output PWM waveform and adds them together using the principle of superposition to calculate the Fourier coefficients of the all PWM output signal. Harmonic magnitudes can be calculated directly by this method without linearization, using look-up tables or Bessel functions. In this study, the results obtained in the application of SVPWM for values of variable parameters are compared with the results obtained with the multiple-pulses method.
Modelling and Analysis of DFIG Wind Turbine Harmonics Generated in Grids
A.Chilambuchelvan; B.BabyPriya,
2010-01-01
In this paper an analytic technique for modelling harmonics is proposed for a DFIG wind turbine connected to the grid. An algorithm based on Hilbert transform for the analysis of harmonics in power systems isdeveloped. The simulation results prove the effectiveness of the Hilbert Transform (HT) for power harmonic analysis in DFIG wind turbine connected to a grid.
A Massively Parallel Solver for the Mechanical Harmonic Analysis of Accelerator Cavities
International Nuclear Information System (INIS)
2015-01-01
ACE3P is a 3D massively parallel simulation suite that developed at SLAC National Accelerator Laboratory that can perform coupled electromagnetic, thermal and mechanical study. Effectively utilizing supercomputer resources, ACE3P has become a key simulation tool for particle accelerator R and D. A new frequency domain solver to perform mechanical harmonic response analysis of accelerator components is developed within the existing parallel framework. This solver is designed to determine the frequency response of the mechanical system to external harmonic excitations for time-efficient accurate analysis of the large-scale problems. Coupled with the ACE3P electromagnetic modules, this capability complements a set of multi-physics tools for a comprehensive study of microphonics in superconducting accelerating cavities in order to understand the RF response and feedback requirements for the operational reliability of a particle accelerator. (auth)
Cabrelli, Carlos; Jaffard, Stephane; Molter, Ursula
2016-01-01
This volume is a selection of written notes corresponding to courses taught at the CIMPA School: "New Trends in Applied Harmonic Analysis: Sparse Representations, Compressed Sensing and Multifractal Analysis". New interactions between harmonic analysis and signal and image processing have seen striking development in the last 10 years, and several technological deadlocks have been solved through the resolution of deep theoretical problems in harmonic analysis. New Trends in Applied Harmonic Analysis focuses on two particularly active areas that are representative of such advances: multifractal analysis, and sparse representation and compressed sensing. The contributions are written by leaders in these areas, and covers both theoretical aspects and applications. This work should prove useful not only to PhD students and postdocs in mathematics and signal and image processing, but also to researchers working in related topics.
Harmonic Analysis Associated with the Generalized Weinstein Operator
Directory of Open Access Journals (Sweden)
Ahmed Abouelaz
2015-11-01
Full Text Available In this paper we consider a generalized Weinstein operator ∆d,α,n on Rd−1×]0,∞[, which generalizes the Weinstein operator ∆d,α, we define the generalized Weinstein intertwining operator Rα,n which turn out to be transmutation operator between ∆d,α,n and the Laplacian operator ∆d. We build the dual of the generalized Weinstein intertwining operatortRα,n, another hand we prove the formula related Rα,n andtRα,n . We exploit these transmutation operators to develop a new harmonic analysis corresponding to ∆d,α,n.
Using harmonical analysis for experimental verification of reactor dynamics
International Nuclear Information System (INIS)
Hrstka, V.
1974-01-01
The questions are discussed of the accuracy of the method of static programming when applied to digital harmonic analysis, with regard to the variation of the mean value of the analyzed signals, and to the use of symmetrical trapezoidal periodical signals. The evaluation is made of the suitability of the above-mentioned method in determining the frequency characteristic of the SR-OA reactor. The results obtained were applied to planning the start-up experiments of the KS-150 reactor at the A-1 nuclear power station. (author)
Analysis of Even Harmonics Generation in an Isolated Electric Power System
Kanao, Norikazu; Hayashi, Yasuhiro; Matsuki, Junya
Harmonics bred from loads are mainly odd order because the current waveform has half-wave symmetry. Since the even harmonics are negligibly small, those are not generally measured in electric power systems. However, even harmonics were measured at a 500/275/154kV substation in Hokuriku Electric Power Company after removal of a transmission line fault. The even harmonics caused malfunctions of protective digital relays because the relays used 4th harmonics at the input filter as automatic supervisory signal. This paper describes the mechanism of generation of the even harmonics by comparing measured waveforms with ATP-EMTP simulation results. As a result of analysis, it is cleared that even harmonics are generated by three causes. The first cause is a magnetizing current of transformers due to flux deviation by DC component of a fault current. The second one is due to harmonic conversion of a synchronous machine which generates even harmonics when direct current component or even harmonic current flow into the machine. The third one is that increase of harmonic impedance due to an isolated power system produces harmonic voltages. The design of the input filter of protective digital relays should consider even harmonics generation in an isolated power system.
International Nuclear Information System (INIS)
Yeh, Y.S.; Chang, T.H.; Wu, T.S.
2004-01-01
A comparative analysis between the fundamental and second cyclotron harmonics of gyrotron backward-wave oscillators (gyro-BWOs) is presented. The simulation results reveal that nonlinear field contraction is a common feature for both harmonic interactions. Besides, the electron transit angle, used to characterize the axial modes of the fundamental harmonic TE 11 mode at the start-oscillation conditions, is found to be applicable even for the second harmonic TE 21 mode. Each axial mode of either the fundamental harmonic TE 11 or the second harmonic TE 21 modes is maintained at a constant value of the electron transit angle while changing the operating parameters, such as magnetic field and beam voltage. Extensive numerical calculations are conducted for the start-oscillation currents and tuning properties. Moreover, single-mode operating regimes are suggested where the second harmonic TE 21 gyro-BWO could generate a considerable output power, comparing with the fundamental harmonic TE 11 gyro-BWO
One dimension harmonic oscillator
International Nuclear Information System (INIS)
Cohen-Tannoudji, Claude; Diu, Bernard; Laloe, Franck.
1977-01-01
The importance of harmonic oscillator in classical and quantum physics, eigenvalues and eigenstates of hamiltonian operator are discussed. In complement are presented: study of some physical examples of harmonic oscillators; study of stationnary states in the /x> representation; Hermite polynomials; resolution of eigenvalue equation of harmonic oscillator by polynomial method; isotope harmonic oscillator with three dimensions; charged harmonic oscillator in uniform electric field; quasi classical coherent states of harmonic oscillator; eigenmodes of vibration of two coupled harmonic oscillators; vibration modus of a continuous physical system (application to radiation: photons); vibration modus of indefinite linear chain of coupled harmonic oscillators (phonons); one-dimensional harmonic oscillator in thermodynamic equilibrium at temperature T [fr
Chirp analysis of high-order harmonics from atoms driven by intense femtosecond laser pulses
International Nuclear Information System (INIS)
Kim, Hyung Taek; Kim, I Jong; Hong, Kyung-Han; Lee, Dong Gun; Kim, Jung-Hoon; Nam, Chang Hee
2004-01-01
The spectral structure of harmonics was experimentally controlled by changing the chirp of femtosecond laser pulses, and the dependence of harmonic chirp on atomic species was analysed using harmonics from neon and helium. Experimental results and theoretical analysis based on the Wigner distribution function showed that the spectral structure varied sensitively to laser chirp and the harmonic chirp was determined by the competition between dynamically induced negative chirp and self-phase modulation induced positive chirp. The generation of sharp and bright harmonics was achieved with appropriately chirped laser pulses under given experimental conditions, especially negatively chirped pulses in the case of laser intensity above the saturation intensity for optical-field ionization
DEFF Research Database (Denmark)
Kwon, Jun Bum; Wang, Xiongfei; Blaabjerg, Frede
2014-01-01
This paper investigates the effect of grid impedance variation on harmonic resonant current controllers for gridconnected voltage source converters by means of impedance-based analysis. It reveals that the negative harmonic resistances tend to be derived from harmonic resonant controllers...... in the closed-loop output admittance of converter. Such negative resistances may interact with the grid impedance resulting in steady state error or unstable harmonic compensation. To deal with this problem, a design guideline for harmonic resonant controllers under a wide range of grid impedance is proposed...
Time-frequency analysis and harmonic Gaussian functions
International Nuclear Information System (INIS)
Ranaivoson, R.T.R; Raoelina Andriambololona; Hanitriarivo, R.
2013-01-01
A method for time-frequency analysis is given. The approach utilizes properties of Gaussian distribution, properties of Hermite polynomials and Fourier analysis. We begin by the definitions of a set of functions called Harmonic Gaussian Functions. Then these functions are used to define a set of transformations, noted Τ n , which associate to a function ψ, of the time variable t, a set of functions Ψ n which depend on time, frequency and frequency (or time) standard deviation. Some properties of the transformations Τ n and the functions Ψ n are given. It is proved in particular that the square of the modulus of each function Ψ n can be interpreted as a representation of the energy distribution of the signal, represented by the function ψ, in the time-frequency plane for a given value of the frequency (or time) standard deviation. It is also shown that the function ψ can be recovered from the functions Ψ n .
Harmonic Analysis on Torque Ripple of Brushless DC Motor Based on Advanced Commutation Control
Directory of Open Access Journals (Sweden)
Yanpeng Ji
2018-01-01
Full Text Available This paper investigates the relationship between current, back electromotive force (back-EMF, and torque for permanent-magnet brushless DC (PM BLDC motors under advanced commutation control from the perspective of harmonics. Considering that the phase current is the influencing factor of both torque and torque ripple, this paper firstly analyzes the effects of advanced commutation on phase current and current harmonics. And then, based on the harmonics of the phase current and back-EMF, the torque harmonic expressions are deduced. The expressions reveal the relationship of harmonic order between the torque, phase current, and back-EMF and highlight the different contribution of individual torque harmonic to the total torque ripple. Finally, the proposed harmonic analysis method is verified by the experiments with different speed and load conditions.
Research of second harmonic generation images based on texture analysis
Liu, Yao; Li, Yan; Gong, Haiming; Zhu, Xiaoqin; Huang, Zufang; Chen, Guannan
2014-09-01
Texture analysis plays a crucial role in identifying objects or regions of interest in an image. It has been applied to a variety of medical image processing, ranging from the detection of disease and the segmentation of specific anatomical structures, to differentiation between healthy and pathological tissues. Second harmonic generation (SHG) microscopy as a potential noninvasive tool for imaging biological tissues has been widely used in medicine, with reduced phototoxicity and photobleaching. In this paper, we clarified the principles of texture analysis including statistical, transform, structural and model-based methods and gave examples of its applications, reviewing studies of the technique. Moreover, we tried to apply texture analysis to the SHG images for the differentiation of human skin scar tissues. Texture analysis method based on local binary pattern (LBP) and wavelet transform was used to extract texture features of SHG images from collagen in normal and abnormal scars, and then the scar SHG images were classified into normal or abnormal ones. Compared with other texture analysis methods with respect to the receiver operating characteristic analysis, LBP combined with wavelet transform was demonstrated to achieve higher accuracy. It can provide a new way for clinical diagnosis of scar types. At last, future development of texture analysis in SHG images were discussed.
Non-homogeneous harmonic analysis: 16 years of development
Volberg, A. L.; Èiderman, V. Ya
2013-12-01
This survey contains results and methods in the theory of singular integrals, a theory which has been developing dramatically in the last 15-20 years. The central (although not the only) topic of the paper is the connection between the analytic properties of integrals and operators with Calderón-Zygmund kernels and the geometric properties of the measures. The history is traced of the classical Painlevé problem of describing removable singularities of bounded analytic functions, which has provided a strong incentive for the development of this branch of harmonic analysis. The progress of recent decades has largely been based on the creation of an apparatus for dealing with non-homogeneous measures, and much attention is devoted to this apparatus here. Several open questions are stated, first and foremost in the multidimensional case, where the method of curvature of a measure is not available. Bibliography: 128 titles.
International Nuclear Information System (INIS)
Gover, A.; Friedman, A.; Luccio, A.
1986-09-01
A full 3-D Analysis of super-radiant (bunched electron) free electron harmonic radiation is presented. A generalized form of the FEL pendulum equation was derived and numerically solved. Both spectral and phasor formulation were developed to treat the radiation in the time domain. In space the radiation field is expanded in terms of either a set of free space discrete modes or plane waves. The numerical solutions reveal some new distinctly 3-D effects to which we provide a physical explanation. 12 refs., 9 figs., 5 tabs
DEFF Research Database (Denmark)
Kwon, Jun Bum; Wang, Xiongfei; Bak, Claus Leth
2015-01-01
As the number of power electronics based systems are increasing, studies about overall stability and harmonic problems are rising. In order to analyze harmonics and stability, most research is using an analysis method, which is based on the Linear Time Invariant (LTI) approach. However, this can...... be difficult in terms of complex multi-parallel connected systems, especially in the case of renewable energy, where possibilities for intermittent operation due to the weather conditions exist. Hence, it can bring many different operating points to the power converter, and the impedance characteristics can...... can demonstrate other phenomenon, which can not be found in the conventional LTI approach. The theoretical modeling and analysis are verified by means of simulations and experiments....
Recent Developments in Real and Harmonic Analysis In Honor of Carlos Segovia
Cabrelli, Carlos A
2008-01-01
Featuring a collection of invited chapters dedicated to Carlos Segovia, this volume examines the developments in real and harmonic analysis. It includes topics such as: Vector-valued singular integral equations; Harmonic analysis related to Hermite expansions; Gas flow in porous media; and, Global well-posedness of the KPI Equation
The Harmonic Walk: An Interactive Physical Environment to Learn Tonal Melody Accompaniment
Directory of Open Access Journals (Sweden)
Marcella Mandanici
2016-01-01
Full Text Available The Harmonic Walk is an interactive physical environment designed for learning and practicing the accompaniment of a tonal melody. Employing a highly innovative multimedia system, the application offers to the user the possibility of getting in touch with some fundamental tonal music features in a very simple and readily available way. Notwithstanding tonal music is very common in our lives, unskilled people as well as music students and even professionals are scarcely conscious of what these features actually are. The Harmonic Walk, through the body movement in space, can provide all these users a live experience of tonal melody structure, chords progressions, melody accompaniment, and improvisation. Enactive knowledge and embodied cognition allow the user to build an inner map of these musical features, which can be acted by moving on the active surface with a simple step. Thorough assessment tests with musicians and nonmusicians high school students could prove the high communicative power and efficiency of the Harmonic Walk application both in improving musical knowledge and in accomplishing complex musical tasks.
Harmonic Coupling Analysis of a Multi-Drive System with Slim DC-link Drive
DEFF Research Database (Denmark)
Yang, Feng; Kwon, Jun Bum; Blaabjerg, Frede
2017-01-01
One of the problems with slim dc-link adjustable speed drive is the difficulties to analyze the harmonic coupling when it is integrated into a multi-drive system. The traditional methods analyze this harmonic issue by neglecting the harmonic coupling, and base on the linear time-invariant methods....... Its disadvantages include the time consumption and large computer memory. This paper proposes to do harmonic analysis by using the harmonic state-space modeling method by using the linear time-periodic theory. By using the proposed model, the harmonic couplings, between dc-link and point of common...... coupling in different drives, are all analyzed in the multi-drive system. In the meantime, the effects of the small film dc-link capacitance and the nonlinear characteristic of the diode rectifier are considered. The detailed modeling procedure, the simulations and the lab experiment on a two-drive system...
DEFF Research Database (Denmark)
Kwon, Jun Bum; Wang, Xiongfei; Bak, Claus Leth
2015-01-01
Understanding about harmonic propagation in wind turbine converter is fundamental to research the influence of these on a large network harmonic distortion. Therefore, the analysis of wind turbine converter harmonic spectrum as well as the influence of converter operating point into the network i...... connected into the large wind farm model to analyze the overall steady-state harmonic as well as harmonic stability. All theoretical modeling and analysis is verified by means of simulation and experimental results.......Understanding about harmonic propagation in wind turbine converter is fundamental to research the influence of these on a large network harmonic distortion. Therefore, the analysis of wind turbine converter harmonic spectrum as well as the influence of converter operating point into the network...... is urgently important issues in harmonic studies on wind farm. However, the conventional modeling procedure and simplified model for controller design are not enough to analyze such complicated systems. Besides, they have many limitations in terms of including a non-linear component, different operating...
Statistical Analysis and Comparison of Harmonics Measured in Offshore Wind Farms
DEFF Research Database (Denmark)
Kocewiak, Lukasz Hubert; Hjerrild, Jesper; Bak, Claus Leth
2011-01-01
The paper shows statistical analysis of harmonic components measured in different offshore wind farms. Harmonic analysis is a complex task and requires many aspects, such as measurements, data processing, modeling, validation, to be taken into consideration. The paper describes measurement process...... and shows sophisticated analysis on representative harmonic measurements from Avedøre Holme, Gunfleet Sands and Burbo Bank wind farms. The nature of generation and behavior of harmonic components in offshore wind farms clearly presented and explained based on probabilistic approach. Some issues regarding...... commonly applied standards are also put forward in the discussion. Based on measurements and data analysis it is shown that a general overview about wind farm harmonic behaviour cannot be fully observed only based on single-value measurements as suggested in the standards but using more descriptive...
Non-Harmonic Fourier Analysis for bladed wheels damage detection
Neri, P.; Peeters, B.
2015-11-01
The interaction between bladed wheels and the fluid distributed by the stator vanes results in cyclic loading of the rotating components. Compressors and turbines wheels are subject to vibration and fatigue issues, especially when resonance conditions are excited. Even if resonance conditions can be often predicted and avoided, high cycle fatigue failures can occur, causing safety issues and economic loss. Rigorous maintenance programs are then needed, forcing the system to expensive shut-down. Blade crack detection methods are beneficial for condition-based maintenance. While contact measurement systems are not always usable in exercise conditions (e.g. high temperature), non-contact methods can be more suitable. One (or more) stator-fixed sensor can measure all the blades as they pass by, in order to detect the damaged ones. The main drawback in this situation is the short acquisition time available for each blade, which is shortened by the high rotational speed of the components. A traditional Discrete Fourier Transform (DFT) analysis would result in a poor frequency resolution. A Non-Harmonic Fourier Analysis (NHFA) can be executed with an arbitrary frequency resolution instead, allowing to obtain frequency information even with short-time data samples. This paper shows an analytical investigation of the NHFA method. A data processing algorithm is then proposed to obtain frequency shift information from short time samples. The performances of this algorithm are then studied by experimental and numerical tests.
Comparative analysis of harmonized forest area stimates for European countries
DEFF Research Database (Denmark)
Seebach, Lucia Maria; Strobl, P.; Miguel-Ayanz, J. San
2011-01-01
Harmonized forest area information provides an important basis for environmental modelling and policy-making at both national and international levels. Traditionally, this information has been provided by national forest inventory statistics but is now increasingly complemented with remote sensing...
Harmonic Analysis of Electric Vehicle Loadings on Distribution System
Energy Technology Data Exchange (ETDEWEB)
Xu, Yijun A [University of Southern California, Department of Electrical Engineering; Xu, Yunshan [University of Southern California, Department of Electrical Engineering; Chen, Zimin [University of Southern California, Department of Electrical Engineering; Peng, Fei [University of Southern California, Department of Electrical Engineering; Beshir, Mohammed [University of Southern California, Department of Electrical Engineering
2014-12-01
With the increasing number of Electric Vehicles (EV) in this age, the power system is facing huge challenges of the high penetration rates of EVs charging stations. Therefore, a technical study of the impact of EVs charging on the distribution system is required. This paper is applied with PSCAD software and aimed to analyzing the Total Harmonic Distortion (THD) brought by Electric Vehicles charging stations in power systems. The paper starts with choosing IEEE34 node test feeder as the distribution system, building electric vehicle level two charging battery model and other four different testing scenarios: overhead transmission line and underground cable, industrial area, transformer and photovoltaic (PV) system. Then the statistic method is used to analyze different characteristics of THD in the plug-in transient, plug-out transient and steady-state charging conditions associated with these four scenarios are taken into the analysis. Finally, the factors influencing the THD in different scenarios are found. The analyzing results lead the conclusion of this paper to have constructive suggestions for both Electric Vehicle charging station construction and customers' charging habits.
Harmonic analysis of the stability of reverse routing in channels
Directory of Open Access Journals (Sweden)
2007-01-01
Full Text Available Normal downstream routing of a flood flow is a highly stable process for Froude numbers less than 1 and hence the results are reliable. In contrast, reverse routing in an upstream direction, which may be required for flow control, is potentially unstable. This paper reports the results of a study of the practical limits on channel lengths for reverse routing. Harmonic analysis is applied to the full non-linear solution of the St. Venant equations for three different wave patterns and two different wave periods, for a particular channel with a Froude number of 0.5. Reverse routing can be done for prismatic channels longer than 100 km. For long periods (>10 hours the shape of the upstream hydrograph is recovered well. However, when the wave period is short (<1 hour, the high frequency components of the upstream hydrograph and, thus, its shape, are not recovered. These limits are influenced by the channel morphology and shape of the wave. Further work is needed to determine how these factors interact.
Applied and computational harmonic analysis on graphs and networks
Irion, Jeff; Saito, Naoki
2015-09-01
In recent years, the advent of new sensor technologies and social network infrastructure has provided huge opportunities and challenges for analyzing data recorded on such networks. In the case of data on regular lattices, computational harmonic analysis tools such as the Fourier and wavelet transforms have well-developed theories and proven track records of success. It is therefore quite important to extend such tools from the classical setting of regular lattices to the more general setting of graphs and networks. In this article, we first review basics of graph Laplacian matrices, whose eigenpairs are often interpreted as the frequencies and the Fourier basis vectors on a given graph. We point out, however, that such an interpretation is misleading unless the underlying graph is either an unweighted path or cycle. We then discuss our recent effort of constructing multiscale basis dictionaries on a graph, including the Hierarchical Graph Laplacian Eigenbasis Dictionary and the Generalized Haar-Walsh Wavelet Packet Dictionary, which are viewed as generalizations of the classical hierarchical block DCTs and the Haar-Walsh wavelet packets, respectively, to the graph setting. Finally, we demonstrate the usefulness of our dictionaries by using them to simultaneously segment and denoise 1-D noisy signals sampled on regular lattices, a problem where classical tools have difficulty.
The analysis of harmonic generation coefficients in the ablative Rayleigh-Taylor instability
Lu, Yan; Fan, Zhengfeng; Lu, Xinpei; Ye, Wenhua; Zou, Changlin; Zhang, Ziyun; Zhang, Wen
2017-10-01
In this research, we use the numerical simulation method to investigate the generation coefficients of the first three harmonics and the zeroth harmonic in the Ablative Rayleigh-Taylor Instability. It is shown that the interface shifts to the low temperature side during the ablation process. In consideration of the third-order perturbation theory, the first three harmonic amplitudes of the weakly nonlinear regime are calculated and then the harmonic generation coefficients are obtained by curve fitting. The simulation results show that the harmonic generation coefficients changed with time and wavelength. Using the higher-order perturbation theory, we find that more and more harmonics are generated in the later weakly nonlinear stage, which is caused by the negative feedback of the later higher harmonics. Furthermore, extending the third-order theory to the fifth-order theory, we find that the second and the third harmonics coefficients linearly depend on the wavelength, while the feedback coefficients are almost constant. Further analysis also shows that when the fifth-order theory is considered, the normalized effective amplitudes of second and third harmonics can reach about 25%-40%, which are only 15%-25% in the frame of the previous third-order theory. Therefore, the third order perturbation theory is needed to be modified by the higher-order theory when ηL reaches about 20% of the perturbation wavelength.
Harmonic analysis a comprehensive course in analysis, part 3
Simon, Barry
2015-01-01
A Comprehensive Course in Analysis by Poincaré Prize winner Barry Simon is a five-volume set that can serve as a graduate-level analysis textbook with a lot of additional bonus information, including hundreds of problems and numerous notes that extend the text and provide important historical background. Depth and breadth of exposition make this set a valuable reference source for almost all areas of classical analysis. Part 3 returns to the themes of Part 1 by discussing pointwise limits (going beyond the usual focus on the Hardy-Littlewood maximal function by including ergodic theorems and m
Analysis of higher order harmonics with holographic reflection gratings
Mas-Abellan, P.; Madrigal, R.; Fimia, A.
2017-05-01
Silver halide emulsions have been considered one of the most energetic sensitive materials for holographic applications. Nonlinear recording effects on holographic reflection gratings recorded on silver halide emulsions have been studied by different authors obtaining excellent experimental results. In this communication specifically we focused our investigation on the effects of refractive index modulation, trying to get high levels of overmodulation that will produce high order harmonics. We studied the influence of the overmodulation and its effects on the transmission spectra for a wide exposure range by use of 9 μm thickness films of ultrafine grain emulsion BB640, exposed to single collimated beams using a red He-Ne laser (wavelength 632.8 nm) with Denisyuk configuration obtaining a spatial frequency of 4990 l/mm recorded on the emulsion. The experimental results show that high overmodulation levels of refractive index produce second order harmonics with high diffraction efficiency (higher than 75%) and a narrow grating bandwidth (12.5 nm). Results also show that overmodulation produce diffraction spectra deformation of the second order harmonic, transforming the spectrum from sinusoidal to approximation of square shape due to very high overmodulation. Increasing the levels of overmodulation of refractive index, we have obtained higher order harmonics, obtaining third order harmonic with diffraction efficiency (up to 23%) and narrowing grating bandwidth (5 nm). This study is the first step to develop a new easy technique to obtain narrow spectral filters based on the use of high index modulation reflection gratings.
Mei, Liang; Svanberg, Sune
2015-03-20
This work presents a detailed study of the theoretical aspects of the Fourier analysis method, which has been utilized for gas absorption harmonic detection in wavelength modulation spectroscopy (WMS). The lock-in detection of the harmonic signal is accomplished by studying the phase term of the inverse Fourier transform of the Fourier spectrum that corresponds to the harmonic signal. The mathematics and the corresponding simulation results are given for each procedure when applying the Fourier analysis method. The present work provides a detailed view of the WMS technique when applying the Fourier analysis method.
Eliminating the Influence of Harmonic Components in Operational Modal Analysis
DEFF Research Database (Denmark)
Jacobsen, Niels-Jørgen; Andersen, Palle; Brincker, Rune
2007-01-01
structures, in contrast, are subject inherently to deterministic forces due to the rotating parts in the machinery. These forces are seen as harmonic components in the responses, and their influence should be eliminated before extracting the modes in their vicinity. This paper describes a new method based...... on the well-known Enhanced Frequency Domain Decomposition (EFDD) technique for eliminating these harmonic components in the modal parameter extraction process. For assessing the quality of the method, various experiments were carried out where the results were compared with those obtained with pure stochastic...
International Conference on Geometric and Harmonic Analysis on Homogeneous Spaces and Applications
Nomura, Takaaki
2017-01-01
This book provides the latest competing research results on non-commutative harmonic analysis on homogeneous spaces with many applications. It also includes the most recent developments on other areas of mathematics including algebra and geometry. Lie group representation theory and harmonic analysis on Lie groups and on their homogeneous spaces form a significant and important area of mathematical research. These areas are interrelated with various other mathematical fields such as number theory, algebraic geometry, differential geometry, operator algebra, partial differential equations and mathematical physics. Keeping up with the fast development of this exciting area of research, Ali Baklouti (University of Sfax) and Takaaki Nomura (Kyushu University) launched a series of seminars on the topic, the first of which took place on November 2009 in Kerkennah Islands, the second in Sousse on December 2011, and the third in Hammamet& nbsp;on December 2013. The last seminar, which took place on Dece...
Harmonic Active Filtering and Impedance-based Stability Analysis in Offshore Wind Power Plants
DEFF Research Database (Denmark)
Dhua, Debasish; Yang, Guangya; Zhang, Zhe
2017-01-01
installation and provides effectively similar functionality as passive filters. This work is focused on harmonic propagation studies in wind power plants, power quality evaluation at the point of connection and harmonic mitigation by active filtering. Finally, an impedance-based stability analysis......Nowadays, to eliminate harmonics injected by the wind turbines in offshore wind power plants there is a need to install passive filters. Moreover, the passive filters are not adaptive to harmonic profile changes due to topology changes, grid loading etc. Therefore, active filters in wind turbines...... are proposed as a flexible harmonic mitigation measure. The motivation of this study is to explore the possibility of embedding active filtering in wind turbine grid-side converters without having to change the system electrical infrastructure. The active filtering method can prevent additional equipment...
Precise Model Analysis for 3-phase High Power Converter using the Harmonic State Space Modeling
DEFF Research Database (Denmark)
Kwon, Jun Bum; Wang, Xiongfei; Blaabjerg, Frede
2015-01-01
This paper presents about the generalized multi-frequency modeling and analysis methodology, which can be used in control loop design and stability analysis. In terms of the switching frequency of high power converter, there can be harmonics interruption if the voltage source converter has a low...... switching frequency ratio or multi-sampling frequency. The range of the control bandwidth can include the switching component. Thus, the systems become unstable. This paper applies the Harmonic State Space (HSS) Modeling method in order to find out the transfer function for each harmonics terms...
Harmonics and voltage stability analysis in power systems including
Indian Academy of Sciences (India)
In this study, non-sinusoidal quantities and voltage stability, both known as power quality criteria, are examined together in detail. The widespread use of power electronics elements cause the existence of signiﬁcant non-sinusoidal quantities in the system. These non-sinusoidal quantities can create serious harmonic ...
Harmonics and voltage stability analysis in power systems including ...
Indian Academy of Sciences (India)
R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22
two parameters affecting power quality – harmonics and voltage stability. ... is necessary to pay attention to energy system stability in the planning, management, and ... where k ∈ {m, m + 1,... ,n} and n is total number of the buses in the system.
Nonlinear analysis of a cross-coupled quadrature harmonic oscillator
DEFF Research Database (Denmark)
Djurhuus, Torsten; Krozer, Viktor; Vidkjær, Jens
2005-01-01
The dynamic equations governing the cross-coupled quadrature harmonic oscillator are derived assuming quasi-sinusoidal operation. This allows for an investigation of the previously reported tradeoff between close-to-carrier phase noise and quadrature precision. The results explain how nonlinearity...
Harmonics analysis of the photonic time stretch system.
Mei, Yuan; Xu, Boyu; Chi, Hao; Jin, Tao; Zheng, Shilie; Jin, Xiaofeng; Zhang, Xianmin
2016-09-10
Photonic time stretch (PTS) has been intensively investigated in recent decades due to its potential application to ultra-wideband analog-to-digital conversion. A high-speed analog signal can be captured by an electronic analog-to-digital converter (ADC) with the help of the PTS technique, which slows down the speed of signal in the photonic domain. Unfortunately, the process of the time stretch is not linear due to the nonlinear modulation of the electro-optic intensity modulator in the PTS system, which means the undesired harmonics distortion. In this paper, we present an exact analytical model to fully characterize the harmonics generation in the PTS systems for the first time, to the best of our knowledge. We obtain concise and closed-form expressions for all harmonics of the PTS system with either a single-arm Mach-Zehnder modulator (MZM) or a push-pull MZM. The presented model can largely simplify the PTS system design and the system parameters estimation, such as system bandwidth, harmonics power, time-bandwidth product, and dynamic range. The correctness of the mathematic model is verified by the numerical and experimental results.
Nanoantenna harmonic sensor: theoretical analysis of contactless detection of molecules with light
Farhat, Mohamed; Cheng, Mark M C; Le, Khai Q; Chen, Pai-Yen
2015-01-01
The nonlinear harmonic sensor is a popular wireless sensor and radiofrequency identification (RFID) technique, which allows high-performance sensing in a severe interference/clutter background by transmitting a radio wave and detecting its modulated higher-order harmonics. Here we introduce the concept and design of optical harmonic tags based on nonlinear nanoantennas that can contactlessly detect electronic (e.g. electron affinity) and optical (e.g. relative permittivity) characteristics of molecules. By using a dual-resonance gold-molecule–silver nanodipole antenna within the quantum mechanical realm, the spectral form of the second-harmonic scattering can sensitively reveal the physical properties of molecules, paving a new route towards optical molecular sensors and optical identification (OPID) of biological, genetic, and medical events for the 'Internet of Nano-Things'.
Nanoantenna harmonic sensor: theoretical analysis of contactless detection of molecules with light
Farhat, Mohamed
2015-09-25
The nonlinear harmonic sensor is a popular wireless sensor and radiofrequency identification (RFID) technique, which allows high-performance sensing in a severe interference/clutter background by transmitting a radio wave and detecting its modulated higher-order harmonics. Here we introduce the concept and design of optical harmonic tags based on nonlinear nanoantennas that can contactlessly detect electronic (e.g. electron affinity) and optical (e.g. relative permittivity) characteristics of molecules. By using a dual-resonance gold-molecule–silver nanodipole antenna within the quantum mechanical realm, the spectral form of the second-harmonic scattering can sensitively reveal the physical properties of molecules, paving a new route towards optical molecular sensors and optical identification (OPID) of biological, genetic, and medical events for the \\'Internet of Nano-Things\\'.
Nanoantenna harmonic sensor: theoretical analysis of contactless detection of molecules with light
International Nuclear Information System (INIS)
Farhat, Mohamed; Cheng, Mark M C; Chen, Pai-Yen; Le, Khai Q
2015-01-01
The nonlinear harmonic sensor is a popular wireless sensor and radiofrequency identification (RFID) technique, which allows high-performance sensing in a severe interference/clutter background by transmitting a radio wave and detecting its modulated higher-order harmonics. Here we introduce the concept and design of optical harmonic tags based on nonlinear nanoantennas that can contactlessly detect electronic (e.g. electron affinity) and optical (e.g. relative permittivity) characteristics of molecules. By using a dual-resonance gold-molecule–silver nanodipole antenna within the quantum mechanical realm, the spectral form of the second-harmonic scattering can sensitively reveal the physical properties of molecules, paving a new route towards optical molecular sensors and optical identification (OPID) of biological, genetic, and medical events for the ‘Internet of Nano-Things’. (paper)
Harmonic voltage excess problem test and analysis in UHV and EHV grid particular operation mode
Lv, Zhenhua; Shi, Mingming; Fei, Juntao
2018-02-01
The test and analysis of the power quality of some 1000kV UHV transmission lines and 500kV EHV transmission lines is carried out. It is found that there is harmonic voltage excess problems when the power supply of the UHV and EHV voltage line is single-ended or single-loop, the problem basically disappeared after the operation mode change, different operating conditions, the harmonic current has not been greatly affected, indicating that the harmonic voltage changes mainly caused by the system harmonic impedance. With the analysis of MATLAB Simulink system model, it can be seen that there are specific harmonic voltage excess in the system under the specific operating mode, which results in serious distortion of the specific harmonic voltage. Since such phenomena are found in 500kV and 1000kV systems, it is suggested that the test evaluation work should be done under the typical mode of operation in 500kV, 1000kV Planning and construction process to prevent the occurrence of serious distortion and the regional harmonic current monitoring and suppression work should be done.
International Nuclear Information System (INIS)
Oishi, Tetsutarou; Yoshinuma, Mikirou; Ida, Katsumi; Akiyama, Tsuyoshi; Minami, Takashi; Nagaoka, Kenichi; Shimizu, Akihiro; Okamura, Shoichi; Kado, Shinichiro
2008-01-01
The coherent MHD oscillation, which consists of the fundamental frequency of several kilohertz and its higher harmonics, (harmonic oscillation: HO) has been observed in Compact Helical System. HO consists of two pairs of harmonic series. One is located in the core region near the ι=0.5 rational surface (denoted as 'HO (core)'), the other is located in the edge region near the ι=1.0 rational surface (denoted as 'HO (edge)'). In the present study, bispectral analysis is applied to the fluctuation data, for which HO is measured by beam emission spectroscopy (BES) and using magnetic probes. The analysis has revealed that fundamental mode of HO in both the magnetic and core density fluctuations have phase correlation with the harmonics including fundamental oscillation, while HO in edge density fluctuation does not have such phase correlation. Mode numbers of HOs are identical for harmonic components having different frequencies, i.e., m/n=-2/1 for HO (core) and m/n=-1/1 for HO (edge). It suggests that the generation of harmonics cannot be interpreted simply as mode coupling because the summation rule for the wavenumber is not satisfied, even though the bicoherence value is significant. The bicoherence value and relative amplitude of higher harmonics correlate with each other, which suggests that bicoherence indicates the degree of distortion of the signals. (author)
Analysis of the superconducting wiggler magnets for the ATF Harmonic Generation FEL experiment
International Nuclear Information System (INIS)
Zhang, X.; Ben-Zvi, I.; Ingold, G.; Krinsky, S.; Yu, L.H.
1992-01-01
In this paper, we consider the superconducting wiggler magnet under construction for the High Gain Harmonic Generation experiment (HGHG) at the Accelerator Test Facility (ATF) at BNL. This wiggler consists of an energy modulation section, a dispersion magnet and a radiator section. We present an analysis of the dispersion magnet and the end effects in the other wiggler sections. The purpose of the dispersion magnet is to convert energy modulation of the electron beam into spatial bunching. For the dispersion magnet, we discuss the physical requirements, analyze the magnetic design, determine the focusing properties, and consider the effect of departures from ideal behavior on the FEL gain. In the modulator and radiator wigglers we analyze the effects due to the ends of the wiggler and discuss their correction. In addition, the localized field produced by a trim coil for horizontal beam steering is investigated
International Nuclear Information System (INIS)
Actis, Oxana; Brodski, Michael; Erdmann, Martin; Fischer, Robert; Hinzmann, Andreas; Mueller, Gero; Muenzer, Thomas; Plum, Matthias; Steggemann, Jan; Winchen, Tobias; Klimkovich, Tatsiana
2010-01-01
VISPA is a development environment for high energy physics analyses which enables physicists to combine graphical and textual work. A physics analysis cycle consists of prototyping, performing, and verifying the analysis. The main feature of VISPA is a multipurpose window for visual steering of analysis steps, creation of analysis templates, and browsing physics event data at different steps of an analysis. VISPA follows an experiment-independent approach and incorporates various tools for steering and controlling required in a typical analysis. Connection to different frameworks of high energy physics experiments is achieved by using different types of interfaces. We present the look-and-feel for an example physics analysis at the LHC and explain the underlying software concepts of VISPA.
Analysis of Harmonics Suppression by Active Damping Control on Multi Slim DC-link Drives
DEFF Research Database (Denmark)
Yang, Feng; Máthé, Lászlo; Lu, Kaiyuan
2016-01-01
Compared with conventional dc-link drive, slim dc-link drive is expected to achieve lower cost and longer life time. However, harmonics distortion problem may occur in such drive systems. This paper proposes to use an active damping control method to suppress the harmonic distortion...... with the benefit of low cost and also low loss. A new analysis method, based on the frequency domain impedance model, is presented to explore the mechanism of harmonics suppression. Also, a general method is presented to build the impedance model of a PMSM drive system using Field Oriented Control (FOC) method....... Some design issues, including power levels, current control bandwidth and harmonic interaction, are discussed when the drive system is fed by a weak grid. Case studies on a two-drive system composed by two slim dc-link drive units are provided to verify the proposed analysis method....
Bioimpedance harmonic analysis as a tool to simultaneously assess circulation and nervous control.
Mudraya, I S; Revenko, S V; Nesterov, A V; Gavrilov, I Yu; Kirpatovsky, V I
2011-07-01
Multicycle harmonic (Fourier) analysis of bioimpedance was employed to simultaneously assess circulation and neural activity in visceral (rat urinary bladder) and somatic (human finger) organs. The informative value of the first cardiac harmonic of the bladder impedance as an index of bladder circulation is demonstrated. The individual reactions of normal and obstructive bladders in response to infusion cystometry were recorded. The potency of multicycle harmonic analysis of bioimpedance to assess sympathetic and parasympathetic neural control in urinary bladder is discussed. In the human finger, bioimpedance harmonic analysis revealed three periodic components at the rate of the heart beat, respiration and Mayer wave (0.1 Hz), which were observed under normal conditions and during blood flow arrest in the hand. The revealed spectrum peaks were explained by the changes in systemic blood pressure and in regional vascular tone resulting from neural vasomotor control. During normal respiration and circulation, two side cardiac peaks were revealed in a bioimpedance amplitude spectrum, whose amplitude reflected the depth of amplitude respiratory modulation of the cardiac output. During normal breathing, the peaks corresponding to the second and third cardiac harmonics were split, reflecting frequency respiratory modulation of the heart rate. Multicycle harmonic analysis of bioimpedance is a novel potent tool to examine the interaction between the respiratory and cardiovascular system and to simultaneously assess regional circulation and neural influences in visceral and somatic organs.
Improved streaming analysis technique: spherical harmonics expansion of albedo data
International Nuclear Information System (INIS)
Albert, T.E.; Simmons, G.L.
1979-01-01
An improved albedo scattering technique was implemented with a three-dimensional Monte Carlo transport code for use in analyzing radiation streaming problems. The improvement was based on a shifted spherical Harmonics expansion of the doubly differential albedo data base. The result of the improvement was a factor of 3 to 10 reduction in data storage requirements and approximately a factor of 3 to 6 increase in computational speed. Comparisons of results obtained using the technique with measurements are shown for neutron streaming in one- and two-legged square concrete ducts
Allain, Rhett
2016-05-01
We currently live in a world filled with videos. There are videos on YouTube, feature movies and even videos recorded with our own cameras and smartphones. These videos present an excellent opportunity to not only explore physical concepts, but also inspire others to investigate physics ideas. With video analysis, we can explore the fantasy world in science-fiction films. We can also look at online videos to determine if they are genuine or fake. Video analysis can be used in the introductory physics lab and it can even be used to explore the make-believe physics embedded in video games. This book covers the basic ideas behind video analysis along with the fundamental physics principles used in video analysis. The book also includes several examples of the unique situations in which video analysis can be used.
Jin, Tao; Chen, Yiyang; Flesch, Rodolfo C. C.
2017-11-01
Harmonics pose a great threat to safe and economical operation of power grids. Therefore, it is critical to detect harmonic parameters accurately to design harmonic compensation equipment. The fast Fourier transform (FFT) is widely used for electrical popular power harmonics analysis. However, the barrier effect produced by the algorithm itself and spectrum leakage caused by asynchronous sampling often affects the harmonic analysis accuracy. This paper examines a new approach for harmonic analysis based on deducing the modifier formulas of frequency, phase angle, and amplitude, utilizing the Nuttall-Kaiser window double spectrum line interpolation method, which overcomes the shortcomings in traditional FFT harmonic calculations. The proposed approach is verified numerically and experimentally to be accurate and reliable.
Undulator physics and coherent harmonic generation at the MAX-lab electron storage ring
International Nuclear Information System (INIS)
Werin, Sverker.
1991-01-01
This work presents the undulator and harmonic generation project at the electron storage ring MAX-lab at University of Lund. The theory of undulator radiation, laser coherent harmonic generation, optical klystron amplifiers and FELs is treated in one uniform way, with complete solutions of the necessary equations. The permanent magnet undulator is described in some detail, along with the installation of the undulator in the storage ring. Details regarding the emitted radiation, the electron beam path in the undulator and other results are analysed. Finally harmonic generation using a Nd:YAG laser and the creation of coherent photons at the third harmonic (355 nm) is described. (author)
HARMONIC SPACE ANALYSIS OF PULSAR TIMING ARRAY REDSHIFT MAPS
Energy Technology Data Exchange (ETDEWEB)
Roebber, Elinore; Holder, Gilbert, E-mail: roebbere@physics.mcgill.ca [Department of Physics and McGill Space Institute, McGill University, 3600 rue University, Montréal, QC, H3A 2T8 (Canada)
2017-01-20
In this paper, we propose a new framework for treating the angular information in the pulsar timing array (PTA) response to a gravitational wave (GW) background based on standard cosmic microwave background techniques. We calculate the angular power spectrum of the all-sky gravitational redshift pattern induced at the Earth for both a single bright source of gravitational radiation and a statistically isotropic, unpolarized Gaussian random GW background. The angular power spectrum is the harmonic transform of the Hellings and Downs curve. We use the power spectrum to examine the expected variance in the Hellings and Downs curve in both cases. Finally, we discuss the extent to which PTAs are sensitive to the angular power spectrum and find that the power spectrum sensitivity is dominated by the quadrupole anisotropy of the gravitational redshift map.
Second harmonic generation imaging
2013-01-01
Second-harmonic generation (SHG) microscopy has shown great promise for imaging live cells and tissues, with applications in basic science, medical research, and tissue engineering. Second Harmonic Generation Imaging offers a complete guide to this optical modality, from basic principles, instrumentation, methods, and image analysis to biomedical applications. The book features contributions by experts in second-harmonic imaging, including many pioneering researchers in the field. Written for researchers at all levels, it takes an in-depth look at the current state of the art and possibilities of SHG microscopy. Organized into three sections, the book: Provides an introduction to the physics of the process, step-by-step instructions on how to build an SHG microscope, and comparisons with related imaging techniques Gives an overview of the capabilities of SHG microscopy for imaging tissues and cells—including cell membranes, muscle, collagen in tissues, and microtubules in live cells—by summarizing experi...
DEFF Research Database (Denmark)
Kwon, Jun Bum; Wang, Xiongfei; Bak, Claus Leth
2015-01-01
As the increasing of power electronics based systems, not only the component-based analysis but also a systematic interaction analysis with each other systems are being important. Especially studies about the stability and the harmonics interaction are critical in order to establish the required ...
Relationship between harmonic analysis on SU(2) and on SL(2,C)/SU(2)
International Nuclear Information System (INIS)
Healy, D.M. Jr.
1986-01-01
A topic of interest in harmonic analysis is the comparison of Fourier transforms on compact and noncompact spaces. The Poisson summation formula provides a classical example of this idea by providing an explicit relationship between harmonic analysis on the real line R and on the circle S 1 . This dissertation provides a new geometric proof of this formula, and then generalizes this approach to obtain a relationship between Fourier transforms on Upsilon, the space of positive matrices in SL(2,C), and Fourier transforms on SU(2)
Spatio-spectral analysis of ionization times in high-harmonic generation
Energy Technology Data Exchange (ETDEWEB)
Soifer, Hadas, E-mail: hadas.soifer@weizmann.ac.il [Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100 (Israel); Dagan, Michal; Shafir, Dror; Bruner, Barry D. [Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100 (Israel); Ivanov, Misha Yu. [Department of Physics, Imperial College London, South Kensington Campus, SW7 2AZ London (United Kingdom); Max-Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, Max-Born-Strasse 2A, D-12489 Berlin (Germany); Serbinenko, Valeria; Barth, Ingo; Smirnova, Olga [Max-Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, Max-Born-Strasse 2A, D-12489 Berlin (Germany); Dudovich, Nirit [Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100 (Israel)
2013-03-12
Graphical abstract: A spatio-spectral analysis of the two-color oscillation phase allows us to accurately separate short and long trajectories and reconstruct their ionization times. Highlights: ► We perform a complete spatio-spectral analysis of the high harmonic generation process. ► We analyze the ionization times across the entire spatio-spectral plane of the harmonics. ► We apply this analysis to reconstruct the ionization times of both short and long trajectories. - Abstract: Recollision experiments have been very successful in resolving attosecond scale dynamics. However, such schemes rely on the single atom response, neglecting the macroscopic properties of the interaction and the effects of using multi-cycle laser fields. In this paper we perform a complete spatio-spectral analysis of the high harmonic generation process and resolve the distribution of the subcycle dynamics of the recolliding electron. Specifically, we focus on the measurement of ionization times. Recently, we have demonstrated that the addition of a weak, crossed polarized second harmonic field allows us to resolve the moment of ionization (Shafir, 2012) [1]. In this paper we extend this measurement and perform a complete spatio-spectral analysis. We apply this analysis to reconstruct the ionization times of both short and long trajectories showing good agreement with the quantum path analysis.
State-space-based harmonic stability analysis for paralleled grid-connected inverters
DEFF Research Database (Denmark)
Wang, Yanbo; Wang, Xiongfei; Chen, Zhe
2016-01-01
This paper addresses a state-space-based harmonic stability analysis of paralleled grid-connected inverters system. A small signal model of individual inverter is developed, where LCL filter, the equivalent delay of control system, and current controller are modeled. Then, the overall small signal...... model of paralleled grid-connected inverters is built. Finally, the state space-based stability analysis approach is developed to explain the harmonic resonance phenomenon. The eigenvalue traces associated with time delay and coupled grid impedance are obtained, which accounts for how the unstable...... inverter produces the harmonic resonance and leads to the instability of whole paralleled system. The proposed approach reveals the contributions of the grid impedance as well as the coupled effect on other grid-connected inverters under different grid conditions. Simulation and experimental results...
Bus Participation Factor Analysis for Harmonic Instability in Power Electronics Based Power Systems
DEFF Research Database (Denmark)
Ebrahimzadeh, Esmaeil; Blaabjerg, Frede; Wang, Xiongfei
2018-01-01
Compared with the conventional power systems, large-scale power electronics based power systems present a more complex situation, where harmonic instability may be induced by the mutual interactions between the inner control loops of the converters. This paper presents an approach to locate which...... power converters and buses are more sensitive and have significant contribution to the harmonic instability. In the approach, a power electronics based system is introduced as a Multi-Input Multi-Output (MIMO) dynamic system by means of a dynamic admittance matrix. Bus Participation Factors (PFs......) are calculated by the oscillatory mode sensitivity analysis versus the elements of the MIMO transfer function matrix. The PF analysis detects which power electronic converters or buses have a higher participation in harmonic instability excitation than others or at which buses such instability problems have...
Huang, Jinbo; Yu, Yinghua; Wei, Changyuan; Qin, Qinghong; Mo, Qinguo; Yang, Weiping
2015-01-01
Despite the common use of conventional electrocautery in modified radical mastectomy for breast cancer, the harmonic scalpel is recently emerging as a dominant surgical instrument for dissection and haemostasis, which is thought to reduce the morbidity, such as seroma and blood loss. But the results of published trials are inconsistent. So we made the meta-analysis to assess the intraoperative and postoperative endpoints among women undergoing modified radical mastectomy with harmonic scalpel or electrocautery. A comprehensive literature search of case-control studies from PubMed, MEDLINE, EMBASE and Cochrane Library databases involving modified radical mastectomy with harmonic scalpel or electrocautery was performed. We carried out a meta-analysis of primary endpoints including postoperative drainage, seroma development, intraoperative blood loss and secondly endpoints including operative time and wound complications. We used odds ratios (ORs) with 95% confidence intervals (CIs) to evaluate the effect size for categorical outcomes and standardised mean differences (SMDs) for continuous outcomes. A total of 11 studies with 702 patients were included for this meta-analysis. There was significant difference in total postoperative drainage (SMD: -0.74 [95%CI: -1.31, -0.16]; Pelectrocautery in modified radical mastectomy for breast cancer. No difference was found as for operative time between harmonic scalpel dissection and standard electrocautery (SMD: 0.04 [95%CI: -0.41, 0.50]; P = 0.85). Compared to standard electrocautery, harmonic scalpel dissection presents significant advantages in decreasing postoperative drainage, seroma development, intraoperative blood loss and wound complications in modified radical mastectomy for breast cancer, without increasing operative time. Harmonic scalpel can be recommended as a preferential surgical instrument in modified radical mastectomy.
Limitations in Using Multiple Imputation to Harmonize Individual Participant Data for Meta-Analysis.
Siddique, Juned; de Chavez, Peter J; Howe, George; Cruden, Gracelyn; Brown, C Hendricks
2018-02-01
Individual participant data (IPD) meta-analysis is a meta-analysis in which the individual-level data for each study are obtained and used for synthesis. A common challenge in IPD meta-analysis is when variables of interest are measured differently in different studies. The term harmonization has been coined to describe the procedure of placing variables on the same scale in order to permit pooling of data from a large number of studies. Using data from an IPD meta-analysis of 19 adolescent depression trials, we describe a multiple imputation approach for harmonizing 10 depression measures across the 19 trials by treating those depression measures that were not used in a study as missing data. We then apply diagnostics to address the fit of our imputation model. Even after reducing the scale of our application, we were still unable to produce accurate imputations of the missing values. We describe those features of the data that made it difficult to harmonize the depression measures and provide some guidelines for using multiple imputation for harmonization in IPD meta-analysis.
Harmonic analysis of traction power supply system based on wavelet decomposition
Dun, Xiaohong
2018-05-01
With the rapid development of high-speed railway and heavy-haul transport, AC drive electric locomotive and EMU large-scale operation in the country on the ground, the electrified railway has become the main harmonic source of China's power grid. In response to this phenomenon, the need for timely monitoring of power quality problems of electrified railway, assessment and governance. Wavelet transform is developed on the basis of Fourier analysis, the basic idea comes from the harmonic analysis, with a rigorous theoretical model, which has inherited and developed the local thought of Garbor transformation, and has overcome the disadvantages such as window fixation and lack of discrete orthogonally, so as to become a more recently studied spectral analysis tool. The wavelet analysis takes the gradual and precise time domain step in the high frequency part so as to focus on any details of the signal being analyzed, thereby comprehensively analyzing the harmonics of the traction power supply system meanwhile use the pyramid algorithm to increase the speed of wavelet decomposition. The matlab simulation shows that the use of wavelet decomposition of the traction power supply system for harmonic spectrum analysis is effective.
DEFF Research Database (Denmark)
Jacobsen, Niels-Jørgen; Andersen, Palle; Brincker, Rune
2006-01-01
The presence of harmonic components in the measured responses is unavoidable in many applications of Operational Modal Analysis. This is especially true when measuring on mechanical structures containing rotating or reciprocating parts. This paper describes a new method based on the popular...... agreement is found and the method is proven to be an easy-to-use and robust tool for handling responses with deterministic and stochastic content....... Enhanced Frequency Domain Decomposition technique for eliminating the influence of these harmonic components in the modal parameter extraction process. For various experiments, the quality of the method is assessed and compared to the results obtained using broadband stochastic excitation forces. Good...
Comparative analysis of chosen transforms in the context of de-noising harmonic signals
Directory of Open Access Journals (Sweden)
Artur Zacniewski
2015-09-01
Full Text Available In the article, comparison of popular transforms used i.a. in denoising harmonical signals was presented. The division of signals submitted to mathematical analysis was shown and chosen transforms such as Short Time Fourier Transform, Wigner-Ville Distribution, Wavelet Transform and Discrete Cosine Transform were presented. Harmonic signal with white noise added was submitted for research. During research, the parameters of noise were changed to analyze the effects of using particular transform on noised signal. The importance of right choice for transform and its parameters (different for particular kind of transform was shown. Small changes in parameters or different functions used in transform can lead to considerably different results.[b]Keywords[/b]: denoising of harmonical signals, wavelet transform, discrete cosine transform, DCT
Harmonic Stability Analysis of Offshore Wind Farm with Component Connection Method
DEFF Research Database (Denmark)
Hou, Peng; Ebrahimzadeh, Esmaeil; Wang, Xiongfei
2017-01-01
In this paper, an eigenvalue-based harmonic stability analysis method for offshore wind farm is proposed. Considering the internal cable connection layout, a component connection method (CCM) is adopted to divide the system into individual blocks as current controller of converters, LCL filters...
Analysis of Harmonic Injection to the Modulation of Multi-Level ...
African Journals Online (AJOL)
This paper explores the analysis of third and ninth harmonic injection to the modulation of a multilevel diode clamped converter (DCC) at a varying modulation index. The spectral distributions of the various multi-level waveforms obtained under normal modulation index of 0.8 and over modulation index of 1.15 were ...
Virtanen, J.E.; Maten, ter E.J.W.; Beelen, T.G.J.; Honkala, M.; Hulkkonen, M.
2011-01-01
Poor initial conditions for Harmonic Balance (HB) analysis of freerunning oscillators may lead to divergence of the direct Newton-Raphson method or may prevent to find the solution within an optimization approach. We exploit time integration to obtain estimates for the oscillation frequency and for
Virtanen, J.E.; Maten, ter E.J.W.; Honkala, M.; Hulkkonen, M.; Günther, M.; Bartel, A.; Brunk, M.; Schoeps, S.; Striebel, M.
2012-01-01
Poor initial conditions for Harmonic Balance (HB) analysis of free-running oscillators may lead to divergence of the direct Newton-Raphson method or may prevent to find the solution within an optimization approach. We exploit time integration to obtain estimates for the oscillation frequency and for
Harmonic tidal analysis at a few stations using the least squares method
Digital Repository Service at National Institute of Oceanography (India)
Fernandes, A.A.; Das, V.K.; Bahulayan, N.
Using the least squares method, harmonic analysis has been performed on hourly water level records of 29 days at several stations depicting different types of non-tidal noise. For a tidal record at Mormugao, which was free from storm surges (low...
Magnetic saturation in semi-analytical harmonic modeling for electric machine analysis
Sprangers, R.L.J.; Paulides, J.J.H.; Gysen, B.L.J.; Lomonova, E.
2016-01-01
A semi-analytical method based on the harmonic modeling (HM) technique is presented for the analysis of the magneto-static field distribution in the slotted structure of rotating electric machines. In contrast to the existing literature, the proposed model does not require the assumption of infinite
Cherednichenko, A. V.; Cherednichenko, A. V.; Cherednichenko, V. S.
2018-01-01
It is shown that a significant connection exists between the most important harmonics, extracted in the process of harmonic analysis of time series of precipitation in the catchment area of rivers and the amount of runoff. This allowed us to predict the size of the flow for a period of up to 20 years, assuming that the main parameters of the harmonics are preserved at the predicted time interval. The results of such a forecast for three river basins of Kazakhstan are presented.
Frames and other bases in abstract and function spaces novel methods in harmonic analysis
Gia, Quoc; Mayeli, Azita; Mhaskar, Hrushikesh; Zhou, Ding-Xuan
2017-01-01
The first of a two volume set on novel methods in harmonic analysis, this book draws on a number of original research and survey papers from well-known specialists detailing the latest innovations and recently discovered links between various fields. Along with many deep theoretical results, these volumes contain numerous applications to problems in signal processing, medical imaging, geodesy, statistics, and data science. The chapters within cover an impressive range of ideas from both traditional and modern harmonic analysis, such as: the Fourier transform, Shannon sampling, frames, wavelets, functions on Euclidean spaces, analysis on function spaces of Riemannian and sub-Riemannian manifolds, Fourier analysis on manifolds and Lie groups, analysis on combinatorial graphs, sheaves, co-sheaves, and persistent homologies on topological spaces. Volume I is organized around the theme of frames and other bases in abstract and function spaces, covering topics such as: The advanced development of frames, including ...
Pack, Brian W; Montgomery, Laura L; Hetrick, Evan M
2015-10-01
Color measurements, including physical appearance, are important yet often misunderstood and underappreciated aspects of a control strategy for drug substances and drug products. From a patient safety perspective, color can be an important control point for detecting contamination, impurities, and degradation products, with human visual acuity often more sensitive for colored impurities than instrumental techniques such as HPLC. Physical appearance tests and solution color tests can also serve an important role in ensuring that appropriate steps are taken such that clinical trials do not become unblinded when the active material is compared with another product or a placebo. Despite the importance of color tests, compendial visual tests are not harmonized across the major pharmacopoeias, which results in ambiguous specifications of little value, difficult communication of true sample color, and significant extra work required for global registration. Some pharmacopoeias have not yet recognized or adopted technical advances in the instrumental measurement of color and appearance, whereas others begin to acknowledge the advantage of instrumental colorimetry, yet leave implementation of the technology ambiguous. This commentary will highlight the above-mentioned inconsistencies, provide an avenue toward harmonization and modernization, and outline a scientifically sound approach for implementing quantitative technologies for improved measurement, communication, and control of color and appearance for both solutions and solids. Importantly, this manuscript, for the first time, outlines a color method validation approach that is consistent with the International Conference on Harmonization's guidance on the topic of method validation. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.
Directory of Open Access Journals (Sweden)
Nicole M Armstrong
Full Text Available Common scales for physical functioning are not directly comparable without harmonization techniques, complicating attempts to pool data across studies. Our aim was to provide a standardized metric for physical functioning in adults based on basic and instrumental activities of daily living scaled to NIH PROMIS norms. We provide an item bank to compare the difficulty of various physical functioning activities. We used item response theory methods to place 232 basic and instrumental activities of daily living questions, administered across eight intervention studies of middle-aged and older adults (N = 2,556, on a common metric. We compared the scale's precision to an average z-score of items and evaluated criterion validity based on objective measures of physical functioning and Fried's frailty criteria. Model-estimated item thresholds were widely distributed across the range of physical functioning. From test information plots, the lowest precision in each dataset was 0.80. Using power calculations, the sample size needed to detect 25% physical functional decline with 80% power based on the physical functioning factor was less than half of what would be needed using an average z-score. The physical functioning factor correlated in expected directions with objective measurements from the Timed Up and Go task, tandem balance, gait speed, chair stands, grip strength, and frailty status. Item-level harmonization enables direct comparison of physical functioning measures across existing and potentially future studies and across levels of function using a nationally representative metric. We identified key thresholds of physical functioning items in an item bank to facilitate clinical and epidemiologic decision-making.
Limits in the application of harmonic analysis to pulsating stars
Pascual-Granado, J.; Garrido, R.; Suárez, J. C.
2015-09-01
Using ultra-precise data from space instrumentation, we found that the underlying functions of stellar light curves from some AF pulsating stars are non-analytic, and consequently their Fourier expansion is not guaranteed. This result demonstrates that periodograms do not provide a mathematically consistent estimator of the frequency content for this type of variable stars. More importantly, this constitutes the first counterexample against the current paradigm, which considers that any physical process is described by a continuous (band-limited) function that is infinitely differentiable.
Analysis, manifolds and physics
Choquet-Bruhat, Y
2000-01-01
Twelve problems have been added to the first edition; four of them are supplements to problems in the first edition. The others deal with issues that have become important, since the first edition of Volume II, in recent developments of various areas of physics. All the problems have their foundations in volume 1 of the 2-Volume set Analysis, Manifolds and Physics. It would have been prohibitively expensive to insert the new problems at their respective places. They are grouped together at the end of this volume, their logical place is indicated by a number of parenthesis following the title.
Structural relations between nested harmonic sums
International Nuclear Information System (INIS)
Bluemlein, J.
2008-07-01
We describe the structural relations between nested harmonic sums emerging in the description of physical single scale quantities up to the 3-loop level in renormalizable gauge field theories. These are weight w=6 harmonic sums. We identify universal basic functions which allow to describe a large class of physical quantities and derive their complex analysis. For the 3-loop QCD Wilson coefficients 35 basic functions are required, whereas a subset of 15 describes the 3-loop anomalous dimensions. (orig.)
Structural relations between nested harmonic sums
Energy Technology Data Exchange (ETDEWEB)
Bluemlein, J.
2008-07-15
We describe the structural relations between nested harmonic sums emerging in the description of physical single scale quantities up to the 3-loop level in renormalizable gauge field theories. These are weight w=6 harmonic sums. We identify universal basic functions which allow to describe a large class of physical quantities and derive their complex analysis. For the 3-loop QCD Wilson coefficients 35 basic functions are required, whereas a subset of 15 describes the 3-loop anomalous dimensions. (orig.)
Directory of Open Access Journals (Sweden)
Jinbo Huang
Full Text Available Despite the common use of conventional electrocautery in modified radical mastectomy for breast cancer, the harmonic scalpel is recently emerging as a dominant surgical instrument for dissection and haemostasis, which is thought to reduce the morbidity, such as seroma and blood loss. But the results of published trials are inconsistent. So we made the meta-analysis to assess the intraoperative and postoperative endpoints among women undergoing modified radical mastectomy with harmonic scalpel or electrocautery.A comprehensive literature search of case-control studies from PubMed, MEDLINE, EMBASE and Cochrane Library databases involving modified radical mastectomy with harmonic scalpel or electrocautery was performed. We carried out a meta-analysis of primary endpoints including postoperative drainage, seroma development, intraoperative blood loss and secondly endpoints including operative time and wound complications. We used odds ratios (ORs with 95% confidence intervals (CIs to evaluate the effect size for categorical outcomes and standardised mean differences (SMDs for continuous outcomes.A total of 11 studies with 702 patients were included for this meta-analysis. There was significant difference in total postoperative drainage (SMD: -0.74 [95%CI: -1.31, -0.16]; P< 0.01, seroma development[OR: 0.49 (0.34, 0.70; P < 0.01], intraoperative blood loss(SMD: -1.14 [95%CI: -1.81,-0.47]; P < 0.01 and wound complications [OR: 0.38 (0.24, 0.59; P < 0.01] between harmonic scalpel dissection and standard electrocautery in modified radical mastectomy for breast cancer. No difference was found as for operative time between harmonic scalpel dissection and standard electrocautery (SMD: 0.04 [95%CI: -0.41, 0.50]; P = 0.85.Compared to standard electrocautery, harmonic scalpel dissection presents significant advantages in decreasing postoperative drainage, seroma development, intraoperative blood loss and wound complications in modified radical mastectomy for
Richardson, Tim H.; Brittle, Stuart A.
2012-01-01
This paper describes a set of experiments aimed at overcoming some of the difficulties experienced by students learning about the topics of moments of inertia and simple harmonic motion, both of which are often perceived to be complex topics amongst students during their first-year university courses. By combining both subjects in a discussion…
Selected papers on harmonic analysis, groups, and invariants
Nomizu, Katsumi
1997-01-01
This volume contains papers that originally appeared in Japanese in the journal Sūgaku. Ordinarily the papers would appear in the AMS translation of that journal, but to expedite publication the Society has chosen to publish them as a volume of selected papers. The papers range over a variety of topics, including representation theory, differential geometry, invariant theory, and complex analysis.
Analysis of harmonic current interaction in an industrial plant
Cuk, V.; Cobben, J.F.G.; Kling, W.L.; Timens, R.B.
2011-01-01
An analysis of current transients caused by the operation of a nearby device in an industrial plant is presented in the paper. The source of current transients in the factory lighting system was traced to the operation of the nearby six-pulse AC/DC converter. To determine the nature of the
Singular spectrum analysis, Harmonic regression and El-Nino effect ...
Indian Academy of Sciences (India)
42
Keywords: Total ozone; Singular Spectrum Analysis; Spatial interpolation; Multivariate ENSO .... needed for a whole gamut of activities that contribute to the ultimate synthesis ..... −0.0009 3 + 0.0581 2 − 1.0123 + 7.3246, 2 = 0.53…
Application of harmonic analysis in quantitative heart scintigraphy
International Nuclear Information System (INIS)
Fischer, P.; Knopp, R.; Breuel, H.P.
1979-01-01
Quantitative scintigraphy of the heart after equilibrium distribution of a radioactive tracer permits the measurement of time activity curves in the left ventricle during a representative heart cycle with great statistical accuracy. By application of Fourier's analysis, criteria are to be attained in addition for evaluation of the volume curve as a whole. Thus the entire information contained in the volume curve is completely described in a Fourier spectrum. Resynthesis after Fourier transformation seems to be an ideal method of smoothing because of its convergence in the minimum quadratic error for the type of function concerned. (orig./MG) [de
DEFF Research Database (Denmark)
Kwon, JunBum; Wang, Xiongfei; Bak, Claus Leth
2014-01-01
This paper addresses the harmonic compensation error problem existing with parallel connected inverter in the same grid interface conditions by means of impedance-based analysis and modeling. Unlike the single grid connected inverter, it is found that multiple parallel connected inverters and grid...... impedance can make influence to each other if they each have a harmonic compensation function. The analysis method proposed in this paper is based on the relationship between the overall output impedance and input impedance of parallel connected inverter, where controller gain design method, which can...
Isogeometric analysis and harmonic stator-rotor coupling for simulating electric machines
Bontinck, Zeger; Corno, Jacopo; Schöps, Sebastian; De Gersem, Herbert
2018-06-01
This work proposes Isogeometric Analysis as an alternative to classical finite elements for simulating electric machines. Through the spline-based Isogeometric discretization it is possible to parametrize the circular arcs exactly, thereby avoiding any geometrical error in the representation of the air gap where a high accuracy is mandatory. To increase the generality of the method, and to allow rotation, the rotor and the stator computational domains are constructed independently as multipatch entities. The two subdomains are then coupled using harmonic basis functions at the interface which gives rise to a saddle-point problem. The properties of Isogeometric Analysis combined with harmonic stator-rotor coupling are presented. The results and performance of the new approach are compared to the ones for a classical finite element method using a permanent magnet synchronous machine as an example.
Investigations of Low and Moderate Harmonic Fast Wave Physics on CDX-U
International Nuclear Information System (INIS)
Spaleta, J.; Majeski, R.; Phillips, C.K.; Dumont, R.J.; Kaita, R.; Soukhanovskii, V.; Zakharov, L.
2003-01-01
Third harmonic hydrogen cyclotron fast wave heating studies are planned in the near term on CDX-U to investigate the potential for bulk ion heating. In preparation for these studies, the available radio-frequency power in CDX-U has been increased to 0.5 MW. The operating frequency of the CDX-U radio-frequency transmitter was lowered to operate in the range of 8-10 MHz, providing access to the ion harmonic range 2* ∼ 4* in hydrogen. A similar regime is accessible for the 30 MHz radio-frequency system on the National Spherical Torus Experiment (NSTX), at 0.6 Tesla in hydrogen. Preliminary computational studies over the plasma regimes of interest for NSTX and CDX-U indicate the possibility of strong localized absorption on bulk ion species
Directory of Open Access Journals (Sweden)
A.V. Getman
2013-12-01
Full Text Available Theoretical aspects of an experimental determination method for residual and inductive magnetic moments of a technical object are considered. As input data, the technical object magnetic induction signatures obtained under its linear movement near a pair of three-component sensors are used. A magnetic signature integration technique based on spatial harmonic analysis of the magnetic field represented by twenty-four multipole coefficients is introduced.
International Nuclear Information System (INIS)
Mukhtarova, M.I.
1988-01-01
Comparative analysis of approximations, used in the methods of Faddeev equations and hyperspherical harmonics (MHH) was conducted. The differences in solutions of these methods, related with introduction of approximation of sufficient partial states into the three-nucleon problem, is shown. MHH method is preferred. It is shown that MHH advantage can be manifested clearly when studying new classes of interactions: three-particle, Δ-isobar, nonlocal and other interactions
Andrei Razvan Crisan; Melinda Timea Fulop
2014-01-01
Considering the modern market requirements and the government in the last decade that require two information systems: accounting and statistic. In accordance with these requirements, we believe it is very important to analyze the harmonizing of the two systems between Government Finance Statistics (GFS), used in support of macroeconomic analysis and General Purpose Financial Reports (GPFR) according with International Public Sector Accounting Standards, used for making decisions and accounta...
Modeling and analysis of harmonic resonance in a power electronics based AC power system
DEFF Research Database (Denmark)
Wang, Xiongfei; Blaabjerg, Frede; Chen, Zhe
2013-01-01
The dynamic interactions among the interconnected power converters may bring in harmonic resonance in a power electronics based power system. This paper addresses this issue in a power system dominated by multiple current- and voltage-controlled inverters with LCL- and LC-filters. The impedance...... stability criterion. To validate the theoretical analysis, the time domain simulations and experimental tests on a three-inverter-based system are presented....
International Nuclear Information System (INIS)
Johnstad, H.
1989-06-01
The Physics Analysis Workstation (PAW) is a high-level program providing data presentation and statistical or mathematical analysis. PAW has been developed at CERN as an instrument to assist physicists in the analysis and presentation of their data. The program is interfaced to a high level graphics package, based on basic underlying graphics. 3-D graphics capabilities are being implemented. The major objects in PAW are 1 or 2 dimensional binned event data with fixed number of entries per event, vectors, functions, graphics pictures, and macros. Command input is handled by an integrated user interface package, which allows for a variety of choices for input, either with typed commands, or in a tree structure menu driven mode. 6 refs., 1 fig
Analyzing correlation functions with tesseral and Cartesian spherical harmonics
International Nuclear Information System (INIS)
Danielewicz, Pawel; Pratt, Scott
2007-01-01
The dependence of interparticle correlations on the orientation of particle relative momentum can yield unique information on the space-time features of emission in reactions with multiparticle final states. In the present paper, the benefits of a representation and analysis of the three-dimensional correlation information in terms of surface spherical harmonics is presented. The harmonics include the standard complex tesseral harmonics and the real Cartesian harmonics. Mathematical properties of the lesser known Cartesian harmonics are illuminated. The physical content of different angular harmonic components in a correlation is described. The resolving power of different final-state effects with regard to determining angular features of emission regions is investigated. The considered final-state effects include identity interference, strong interactions, and Coulomb interactions. The correlation analysis in terms of spherical harmonics is illustrated with the cases of Gaussian and blast-wave sources for proton-charged meson and baryon-baryon pairs
Blind Analysis in Particle Physics
International Nuclear Information System (INIS)
Roodman, A
2003-01-01
A review of the blind analysis technique, as used in particle physics measurements, is presented. The history of blind analyses in physics is briefly discussed. Next the dangers of and the advantages of a blind analysis are described. Three distinct kinds of blind analysis in particle physics are presented in detail. Finally, the BABAR collaboration's experience with the blind analysis technique is discussed
International Nuclear Information System (INIS)
Kunz, P.F.
1991-04-01
There are many tools used in analysis in High Energy Physics (HEP). They range from low level tools such as a programming language to high level such as a detector simulation package. This paper will discuss some aspects of these tools that are directly associated with the process of analyzing HEP data. Physics analysis tools cover the whole range from the simulation of the interactions of particles to the display and fitting of statistical data. For purposes of this paper, the stages of analysis is broken down to five main stages. The categories are also classified as areas of generation, reconstruction, and analysis. Different detector groups use different terms for these stages thus it is useful to define what is meant by them in this paper. The particle generation stage is a simulation of the initial interaction, the production of particles, and the decay of the short lived particles. The detector simulation stage simulates the behavior of an event in a detector. The track reconstruction stage does pattern recognition on the measured or simulated space points, calorimeter information, etc., and reconstructs track segments of the original event. The event reconstruction stage takes the reconstructed tracks, along with particle identification information and assigns masses to produce 4-vectors. Finally the display and fit stage displays statistical data accumulated in the preceding stages in the form of histograms, scatter plots, etc. The remainder of this paper will consider what analysis tools are available today, and what one might expect in the future. In each stage, the integration of the tools with other stages and the portability of the tool will be analyzed
Principal component analysis of the nonlinear coupling of harmonic modes in heavy-ion collisions
BoŻek, Piotr
2018-03-01
The principal component analysis of flow correlations in heavy-ion collisions is studied. The correlation matrix of harmonic flow is generalized to correlations involving several different flow vectors. The method can be applied to study the nonlinear coupling between different harmonic modes in a double differential way in transverse momentum or pseudorapidity. The procedure is illustrated with results from the hydrodynamic model applied to Pb + Pb collisions at √{sN N}=2760 GeV. Three examples of generalized correlations matrices in transverse momentum are constructed corresponding to the coupling of v22 and v4, of v2v3 and v5, or of v23,v33 , and v6. The principal component decomposition is applied to the correlation matrices and the dominant modes are calculated.
Directory of Open Access Journals (Sweden)
Huaiqing Zhang
2014-01-01
Full Text Available The spectral leakage has a harmful effect on the accuracy of harmonic analysis for asynchronous sampling. This paper proposed a time quasi-synchronous sampling algorithm which is based on radial basis function (RBF interpolation. Firstly, a fundamental period is evaluated by a zero-crossing technique with fourth-order Newton’s interpolation, and then, the sampling sequence is reproduced by the RBF interpolation. Finally, the harmonic parameters can be calculated by FFT on the synchronization of sampling data. Simulation results showed that the proposed algorithm has high accuracy in measuring distorted and noisy signals. Compared to the local approximation schemes as linear, quadric, and fourth-order Newton interpolations, the RBF is a global approximation method which can acquire more accurate results while the time-consuming is about the same as Newton’s.
International Nuclear Information System (INIS)
Mudraya, I S; Revenko, S V; Khodyreva, L A; Markosyan, T G; Dudareva, A A; Ibragimov, A R; Romich, V V; Kirpatovsky, V I
2013-01-01
The novel technique based on harmonic analysis of bioimpedance microvariations with original hard- and software complex incorporating a high-resolution impedance converter was used to assess the neural activity and circulation in human urinary bladder and penis in patients with pelvic pain, erectile dysfunction, and overactive bladder. The therapeutic effects of shock wave therapy and Botulinum toxin detrusor injections were evaluated quantitatively according to the spectral peaks at low 0.1 Hz frequency (M for Mayer wave), respiratory (R) and cardiac (C) rhythms with their harmonics. Enhanced baseline regional neural activity identified according to M and R peaks was found to be presumably sympathetic in pelvic pain patients, and parasympathetic – in patients with overactive bladder. Total pulsatile activity and pulsatile resonances found in the bladder as well as in the penile spectrum characterised regional circulation and vascular tone. The abnormal spectral parameters characteristic of the patients with genitourinary diseases shifted to the norm in the cases of efficient therapy. Bioimpedance harmonic analysis seems to be a potent tool to assess regional peculiarities of circulatory and autonomic nervous activity in the course of patient treatment.
Mudraya, I. S.; Revenko, S. V.; Khodyreva, L. A.; Markosyan, T. G.; Dudareva, A. A.; Ibragimov, A. R.; Romich, V. V.; Kirpatovsky, V. I.
2013-04-01
The novel technique based on harmonic analysis of bioimpedance microvariations with original hard- and software complex incorporating a high-resolution impedance converter was used to assess the neural activity and circulation in human urinary bladder and penis in patients with pelvic pain, erectile dysfunction, and overactive bladder. The therapeutic effects of shock wave therapy and Botulinum toxin detrusor injections were evaluated quantitatively according to the spectral peaks at low 0.1 Hz frequency (M for Mayer wave), respiratory (R) and cardiac (C) rhythms with their harmonics. Enhanced baseline regional neural activity identified according to M and R peaks was found to be presumably sympathetic in pelvic pain patients, and parasympathetic - in patients with overactive bladder. Total pulsatile activity and pulsatile resonances found in the bladder as well as in the penile spectrum characterised regional circulation and vascular tone. The abnormal spectral parameters characteristic of the patients with genitourinary diseases shifted to the norm in the cases of efficient therapy. Bioimpedance harmonic analysis seems to be a potent tool to assess regional peculiarities of circulatory and autonomic nervous activity in the course of patient treatment.
DEFF Research Database (Denmark)
Wang, Yanbo; Wang, Xiongfei; Blaabjerg, Frede
2017-01-01
parameters on the harmonic instability of the power system. Moreover, the harmonic-frequency oscillation modes are identified, where participation analysis is presented to evaluate the contributions of different states to these modes and to further reveal how the system gives rise to harmonic instability......This paper presents a harmonic instability analysis method using state-space modeling and participation analysis in the inverter-fed ac power systems. A full-order state-space model for the droop-controlled Distributed Generation (DG) inverter is built first, including the time delay of the digital...... control system, inner current and voltage control loops, and outer droop-based power control loop. Based on the DG inverter model, an overall state-space model of a two-inverter-fed system is established. The eigenvalue-based stability analysis is then presented to assess the influence of controller...
International Nuclear Information System (INIS)
Deng Ming-Xi; Xiang Yan-Xun
2010-01-01
Within the second-order perturbation approximation, this paper investigates the physical process of generation of the time-domain second harmonic by a primary Lamb wave waveform in an elastic plate. The present work is performed based on the preconditions that the phase velocity matching is satisfied and that the transfer of energy from the primary Lamb wave to the double frequency Lamb wave is not zero. It investigates the influences of the difference between the group velocities of the primary Lamb wave and the double frequency Lamb wave, the propagation distance and the duration of the primary Lamb wave waveform on the envelope shape of the time-domain second harmonic. It finds that the maximum magnitude of the envelope of the second-harmonic waveform can grow within some propagation distance even if the condition of group velocity matching is not satisfied. Our analyses also indicate that the maximum magnitude of the envelope of the second-harmonic waveform is kept constant beyond a specific propagation distance. Furthermore, it concludes that the integration amplitude of the time-domain second-harmonic waveform always grows with propagation distance within the second-order perturbation. The present research yields new physical insight not previously available into the effect of generation of the time-domain second harmonic by propagation of a primary Lamb wave waveform
Quantum efficiency harmonic analysis of exciton annihilation in organic light emitting diodes
Energy Technology Data Exchange (ETDEWEB)
Price, J. S.; Giebink, N. C., E-mail: ncg2@psu.edu [Department of Electrical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)
2015-06-29
Various exciton annihilation processes are known to impact the efficiency roll-off of organic light emitting diodes (OLEDs); however, isolating and quantifying their contribution in the presence of other factors such as changing charge balance continue to be a challenge for routine device characterization. Here, we analyze OLED electroluminescence resulting from a sinusoidal dither superimposed on the device bias and show that nonlinearity between recombination current and light output arising from annihilation mixes the quantum efficiency measured at different dither harmonics in a manner that depends uniquely on the type and magnitude of the annihilation process. We derive a series of analytical relations involving the DC and first harmonic external quantum efficiency that enable annihilation rates to be quantified through linear regression independent of changing charge balance and evaluate them for prototypical fluorescent and phosphorescent OLEDs based on the emitters 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran and platinum octaethylporphyrin, respectively. We go on to show that, in most cases, it is sufficient to calculate the needed quantum efficiency harmonics directly from derivatives of the DC light versus current curve, thus enabling this analysis to be conducted solely from standard light-current-voltage measurement data.
Cwikel, Michael
2017-01-01
This volume is dedicated to the memory of Björn Jawerth. It contains original research contributions and surveys in several of the areas of mathematics to which Björn made important contributions. Those areas include harmonic analysis, image processing, and functional analysis, which are of course interrelated in many significant and productive ways. Among the contributors are some of the world's leading experts in these areas. With its combination of research papers and surveys, this book may become an important reference and research tool. This book should be of interest to advanced graduate students and professional researchers in the areas of functional analysis, harmonic analysis, image processing, and approximation theory. It combines articles presenting new research with insightful surveys written by foremost experts.
DEFF Research Database (Denmark)
Wang, Xiongfei; Blaabjerg, Frede; Loh, Poh Chiang
2014-01-01
This paper addresses the interaction between harmonic resonant controllers and active damping of LCL resonance in voltage source converters. A virtual series R-C damper in parallel with the filter capacitor is proposed with the capacitor current feedback loop. The phase lag resulting from...... crossover frequency defined by the proportional gain of current controller. This is of particular interest for high-performance active harmonic filtering applications and low-pulse-ratio converters. Case studies in experiments validate the theoretical analysis....
Nimata, Masaomi; Okada, Hideki; Kurihara, Kei; Sugimoto, Tsukasa; Honjoh, Tsutomu; Kuroda, Kazuhiko; Yano, Takeo; Tachibana, Hirofumi; Shoji, Masahiro
2018-01-01
Food allergy is a serious health issue worldwide. Implementing allergen labeling regulations is extremely challenging for regulators, food manufacturers, and analytical kit manufacturers. Here we have developed an "amino acid sequence immunoassay" approach to ELISA. The new ELISA comprises of a monoclonal antibody generated via an analyte specific peptide antigen and sodium lauryl sulfate/sulfite solution. This combination enables the antibody to access the epitope site in unfolded analyte protein. The newly developed ELISA recovered 87.1%-106.4% ovalbumin from ovalbumin-incurred model processed foods, thereby demonstrating its applicability as practical egg allergen determination. Furthermore, the comparison of LC-MS/MS and the new ELISA, which targets the amino acid sequence conforming to the LC-MS/MS detection peptide, showed a good agreement. Consequently the harmonization of two methods was demonstrated. The complementary use of the new ELISA and LC-MS analysis can offer a wide range of practical benefits in terms of easiness, cost, accuracy, and efficiency in food allergen analysis. In addition, the new assay is attractive in respect to its easy antigen preparation and predetermined specificity. Graphical abstract The ELISA composing of the monoclonal antibody targeting the amino acid sequence conformed to LC-MS detection peptide, and the protein conformation unfolding reagent was developed. In ovalbumin determination, the developed ELISA showed a good agreement with LC-MS analysis. Consequently the harmonization of immunoassay with LC-MS analysis by using common target amino acid sequence was demonstrated.
Three-dimensional analysis of harmonic generation in high-gain free-electron lasers
International Nuclear Information System (INIS)
Huang, Zhirong; Kim, Kwang-Je
2000-01-01
In a high-gain free-electron laser (FEL) employing a planar undulator, strong bunching at the fundamental wavelength can drive substantial bunching and power levels at the harmonic frequencies. In this paper we investigate the three-dimensional evolution of harmonic radiation based on the coupled Maxwell-Klimontovich equations that take into account nonlinear harmonic interactions. Each harmonic field is a sum of a linear amplification term and a term driven by nonlinear harmonic interactions. After a certain stage of exponential growth, the dominant nonlinear term is determined by interactions of the lower nonlinear harmonics and the fundamental radiation. As a result, the gain length, transverse profile, and temporal structure of the first few harmonics are eventually governed by those of the fundamental. Transversely coherent third-harmonic radiation power is found to approach 1% of the fundamental power level for current high-gain FEL projects
Bladed wheels damage detection through Non-Harmonic Fourier Analysis improved algorithm
Neri, P.
2017-05-01
Recent papers introduced the Non-Harmonic Fourier Analysis for bladed wheels damage detection. This technique showed its potential in estimating the frequency of sinusoidal signals even when the acquisition time is short with respect to the vibration period, provided that some hypothesis are fulfilled. Anyway, previously proposed algorithms showed severe limitations in cracks detection at their early stage. The present paper proposes an improved algorithm which allows to detect a blade vibration frequency shift due to a crack whose size is really small compared to the blade width. Such a technique could be implemented for condition-based maintenance, allowing to use non-contact methods for vibration measurements. A stator-fixed laser sensor could monitor all the blades as they pass in front of the spot, giving precious information about the wheel health. This configuration determines an acquisition time for each blade which become shorter as the machine rotational speed increases. In this situation, traditional Discrete Fourier Transform analysis results in poor frequency resolution, being not suitable for small frequency shift detection. Non-Harmonic Fourier Analysis instead showed high reliability in vibration frequency estimation even with data samples collected in a short time range. A description of the improved algorithm is provided in the paper, along with a comparison with the previous one. Finally, a validation of the method is presented, based on finite element simulations results.
Stanescu, T; Jaffray, D
2018-05-25
Magnetic resonance imaging is expected to play a more important role in radiation therapy given the recent developments in MR-guided technologies. MR images need to consistently show high spatial accuracy to facilitate RT specific tasks such as treatment planning and in-room guidance. The present study investigates a new harmonic analysis method for the characterization of complex 3D fields derived from MR images affected by system-related distortions. An interior Dirichlet problem based on solving the Laplace equation with boundary conditions (BCs) was formulated for the case of a 3D distortion field. The second-order boundary value problem (BVP) was solved using a finite elements method (FEM) for several quadratic geometries - i.e., sphere, cylinder, cuboid, D-shaped, and ellipsoid. To stress-test the method and generalize it, the BVP was also solved for more complex surfaces such as a Reuleaux 9-gon and the MR imaging volume of a scanner featuring a high degree of surface irregularities. The BCs were formatted from reference experimental data collected with a linearity phantom featuring a volumetric grid structure. The method was validated by comparing the harmonic analysis results with the corresponding experimental reference fields. The harmonic fields were found to be in good agreement with the baseline experimental data for all geometries investigated. In the case of quadratic domains, the percentage of sampling points with residual values larger than 1 mm were 0.5% and 0.2% for the axial components and vector magnitude, respectively. For the general case of a domain defined by the available MR imaging field of view, the reference data showed a peak distortion of about 12 mm and 79% of the sampling points carried a distortion magnitude larger than 1 mm (tolerance intrinsic to the experimental data). The upper limits of the residual values after comparison with the harmonic fields showed max and mean of 1.4 mm and 0.25 mm, respectively, with only 1.5% of
DEFF Research Database (Denmark)
Bai, Haofeng; Wang, Xiongfei; Blaabjerg, Frede
2018-01-01
The output currents of high-power Voltage Source Inverters (VSIs) are distorted by the switching harmonics and the background harmonics in the grid voltage. This paper presents an active harmonic filtering scheme for high-power, low-frequency switching VSIs with an additional auxiliary VSI. In th...
Fractal Information by Means of Harmonic Mappings and Some Physical Implications
Directory of Open Access Journals (Sweden)
Maricel Agop
2016-04-01
Full Text Available Considering that the motions of the complex system structural units take place on continuous, but non-differentiable curves, in the frame of the extended scale relativity model (in its Schrödinger-type variant, it is proven that the imaginary part of a scalar potential of velocities can be correlated with the fractal information and, implicitly, with a tensor of “tensions”, which is fundamental in the construction of the constitutive laws of material. In this way, a specific differential geometry based on a Poincaré-type metric of the Lobachevsky plane (which is invariant to the homographic group of transformations and also a specific variational principle (whose field equations represent an harmonic map from the usual space into the Lobachevsky plane are generated. Moreover, fractal information (which is made explicit at any scale resolution is produced, so that the field variables define a gravitational field. This latter situation is specific to a variational principle in the sense of Matzner–Misner and to certain Ernst-type field equations, the fractal information being contained in the material structure and, thus, in its own space associated with it.
Scaling of mode shapes from operational modal analysis using harmonic forces
Brandt, A.; Berardengo, M.; Manzoni, S.; Cigada, A.
2017-10-01
This paper presents a new method for scaling mode shapes obtained by means of operational modal analysis. The method is capable of scaling mode shapes on any structure, also structures with closely coupled modes, and the method can be used in the presence of ambient vibration from traffic or wind loads, etc. Harmonic excitation can be relatively easily accomplished by using general-purpose actuators, also for force levels necessary for driving large structures such as bridges and highrise buildings. The signal processing necessary for mode shape scaling by the proposed method is simple and the method can easily be implemented in most measurement systems capable of generating a sine wave output. The tests necessary to scale the modes are short compared to typical operational modal analysis test time. The proposed method is thus easy to apply and inexpensive relative to some other methods for scaling mode shapes that are available in literature. Although it is not necessary per se, we propose to excite the structure at, or close to, the eigenfrequencies of the modes to be scaled, since this provides better signal-to-noise ratio in the response sensors, thus permitting the use of smaller actuators. An extensive experimental activity on a real structure was carried out and the results reported demonstrate the feasibility and accuracy of the proposed method. Since the method utilizes harmonic excitation for the mode shape scaling, we propose to call the method OMAH.
An approach for spherical harmonic analysis of non-smooth data
Wang, Hansheng; Wu, Patrick; Wang, Zhiyong
2006-12-01
A method is proposed to evaluate the spherical harmonic coefficients of a global or regional, non-smooth, observable dataset sampled on an equiangular grid. The method is based on an integration strategy using new recursion relations. Because a bilinear function is used to interpolate points within the grid cells, this method is suitable for non-smooth data; the slope of the data may be piecewise continuous, with extreme changes at the boundaries. In order to validate the method, the coefficients of an axisymmetric model are computed, and compared with the derived analytical expressions. Numerical results show that this method is indeed reasonable for non-smooth models, and that the maximum degree for spherical harmonic analysis should be empirically determined by several factors including the model resolution and the degree of non-smoothness in the dataset, and it can be several times larger than the total number of latitudinal grid points. It is also shown that this method is appropriate for the approximate analysis of a smooth dataset. Moreover, this paper provides the program flowchart and an internet address where the FORTRAN code with program specifications are made available.
International Nuclear Information System (INIS)
Fox, Ronald F.; Vela-Arevalo, Luz V.
2002-01-01
The problem of multiphoton processes for intense, long-wavelength irradiation of atomic and molecular electrons is presented. The recently developed method of quasiadiabatic time evolution is used to obtain a nonperturbative analysis. When applied to the standard vector potential coupling, an exact auxiliary equation is obtained that is in the electric dipole coupling form. This is achieved through application of the Goeppert-Mayer gauge. While the analysis to this point is general and aimed at microwave irradiation of Rydberg atoms, a Floquet analysis of the auxiliary equation is presented for the special case of the periodically driven harmonic oscillator. Closed form expressions for a complete set of Floquet states are obtained. These are used to demonstrate that for the oscillator case there are no multiphoton resonances
Electric power quality analysis methods. Application to voltage dips and harmonic disturbances
International Nuclear Information System (INIS)
Vanya, Ignatova
2006-10-01
The power quality concerns all the actors in the energy domains, that they are network administrators, suppliers, producers, or consumers of electricity. The research work presented in this PhD thesis is situated in the field of the power quality monitoring. Its objective is to introduce new techniques for analysis of power quality problems. There are different methods designed for the analysis of the power quality disturbances. This method reaches very good performances in the voltage dips analysis, as it allows segmenting, classifying and characterising these power quality disturbances. The periodic systems method allows the theoretical study of the generation and the propagation of harmonic disturbances in the network. Finally, the statistical matrix method has the objective to represent statistically electrical signals without loss of important information. (author)
Harmonics and energy management
International Nuclear Information System (INIS)
Andresen, M.
1993-01-01
To summarize what this paper has presented: Voltage and current non-sinusoidal wave shapes exist in our power system. These harmonics result from the prolific use of non-linear loads. The use of these types of loads is increasing dramatically, partly due to the push to implement energy management techniques involving harmonic generating equipment. Harmonic analysis can identify specific harmonics, their frequency, magnitude, and phase shift referenced to the fundamental. Harmonic distortion forces the use of true RMS multimeters for measurement accuracy. High levels of neutral current and N-G voltages are now possible. Transformers may overheat and fail even though they are below rated capacity. Low power factors due to harmonics cannot be corrected by the installation of capacitors, and knowledge of the fundamental VARs or the displacement power factor is needed to use capacitors alone for power factor correction. The harmonic related problems presented are by no means an exhaustive list. Many other concerns arise when harmonics are involved in the power system. The critical issue behind these problems is that many of the devices being recommended from an energy management point of view are contributing to the harmonic levels, and thus to the potential for harmonic problems. We can no longer live in the sinusoidal mentality if we are to be effective in saving energy and reducing costs
Multivariate analysis methods in physics
International Nuclear Information System (INIS)
Wolter, M.
2007-01-01
A review of multivariate methods based on statistical training is given. Several multivariate methods useful in high-energy physics analysis are discussed. Selected examples from current research in particle physics are discussed, both from the on-line trigger selection and from the off-line analysis. Also statistical training methods are presented and some new application are suggested [ru
New performance in harmonic analysis device generation used for magnetic fields measurements
International Nuclear Information System (INIS)
Evesque, C.; Tkatchenko, M.
1996-01-01
In particle accelerator, correcting high multipole components of magnets are of high importance for quality magnet: to get a pure quadrupole to within 10 -4 , we have to know the field quality to 10 -5 through the 30. order. Our laboratory needed such a very sharp device to find small harmonic components of magnetic field. For harmonic analysis of magnetic field, we adopted the standard method, i.e. a rotating coil connected to a flux integrator. Nowadays, coils measuring azimuthal component of magnetic field are used. In order to obtain correct and accurate measurements, we were guided by two imperatives: first, optimisation of construction constraints and second, comparison of azimuthal and radial component measurements. With this background, this article describes both new technological solutions adopted and new performance obtained. We also discuss the most suitable geometric structure for the coils. We obtained a noiseless signal, a repeatability of 10 -5 and a sensitivity up to 10 -8 Weber for both types of coils. Our device is able to find and measure main component, normal and skew multipole components up to the 32. order, when simulating local defects. The magnetic axis is located within 5 μm. The central gradient is also measured and magnetic length deduced. Complementary functions of two types of coils were noticed in detecting local defects of magnetic structure. (authors)
Harmonic analysis of electric locomotive and traction power system based on wavelet singular entropy
Dun, Xiaohong
2018-05-01
With the rapid development of high-speed railway and heavy-haul transport, the locomotive and traction power system has become the main harmonic source of China's power grid. In response to this phenomenon, the system's power quality issues need timely monitoring, assessment and governance. Wavelet singular entropy is an organic combination of wavelet transform, singular value decomposition and information entropy theory, which combines the unique advantages of the three in signal processing: the time-frequency local characteristics of wavelet transform, singular value decomposition explores the basic modal characteristics of data, and information entropy quantifies the feature data. Based on the theory of singular value decomposition, the wavelet coefficient matrix after wavelet transform is decomposed into a series of singular values that can reflect the basic characteristics of the original coefficient matrix. Then the statistical properties of information entropy are used to analyze the uncertainty of the singular value set, so as to give a definite measurement of the complexity of the original signal. It can be said that wavelet entropy has a good application prospect in fault detection, classification and protection. The mat lab simulation shows that the use of wavelet singular entropy on the locomotive and traction power system harmonic analysis is effective.
New performance in harmonic analysis device generation used for magnetic fields measurements
Energy Technology Data Exchange (ETDEWEB)
Evesque, C.; Tkatchenko, M.
1996-12-31
In particle accelerator, correcting high multipole components of magnets are of high importance for quality magnet: to get a pure quadrupole to within 10{sup -4}, we have to know the field quality to 10{sup -5} through the 30. order. Our laboratory needed such a very sharp device to find small harmonic components of magnetic field. For harmonic analysis of magnetic field, we adopted the standard method, i.e. a rotating coil connected to a flux integrator. Nowadays, coils measuring azimuthal component of magnetic field are used. In order to obtain correct and accurate measurements, we were guided by two imperatives: first, optimisation of construction constraints and second, comparison of azimuthal and radial component measurements. With this background, this article describes both new technological solutions adopted and new performance obtained. We also discuss the most suitable geometric structure for the coils. We obtained a noiseless signal, a repeatability of 10{sup -5} and a sensitivity up to 10{sup -8} Weber for both types of coils. Our device is able to find and measure main component, normal and skew multipole components up to the 32. order, when simulating local defects. The magnetic axis is located within 5 {mu}m. The central gradient is also measured and magnetic length deduced. Complementary functions of two types of coils were noticed in detecting local defects of magnetic structure. (authors).
General exact harmonic analysis of in-plane timoshenko beam structures
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C. A. N. Dias
Full Text Available The exact solution for the problem of damped, steady state response, of in-plane Timoshenko frames subjected to harmonically time varying external forces is here described. The solution is obtained by using the classical dynamic stiffness matrix (DSM, which is non-linear and transcendental in respect to the excitation frequency, and by performing the harmonic analysis using the Laplace transform. As an original contribution, the partial differential coupled governing equations, combining displacements and forces, are directly subjected to Laplace transforms, leading to the member DSM and to the equivalent load vector formulations. Additionally, the members may have rigid bodies attached at any of their ends where, optionally, internal forces can be released. The member matrices are then used to establish the global matrices that represent the dynamic equilibrium of the overall framed structure, preserving close similarity to the finite element method. Several application examples prove the certainty of the proposed method by comparing the model results with the ones available in the literature or with finite element analyses.
Fong Chao, B.
1983-12-01
The homogeneous set of 80-year-long (1900-1979) International Latitude Service (ILS) polar motion data is analyzed using the autoregressive method (Chao and Gilbert, 1980) which resolves and produces estimates for the complex frequency (or frequency and Q) and complex amplitude (or amplitude and phase) of each harmonic component in the data. Principal conclusion of this analysis are that (1) the ILS data support the multiple-component hypothesis of the Chandler wobble (it is found that the Chandler wobble can be adequately modeled as a linear combination of four (coherent) harmonic components, each of which represents a steady, nearly circular, prograte motion, a behavior that is inconsistent with the hypothesis of a single Chandler period excited in a temporally and/or spatially random fashion). (2) the four-component Chandler wobble model ``explains'' the apparent phase reversal during 1920-1940 and the pre-1950 empirical period-amplitude relation, (3) the annual wobble is shown to be rather stationary over the years both in amplitude and in phase and no evidence is found to support the large variations reported by earlier investigations. (4) the Markowitz wobble is found to support the large variations reported by earlier investigations. (4) the Markowitz wobble is found to be marginally retrograde and appears to have a complicated behavior which cannot be resolved because of the shortness of the data set.
Shan, Mao
2016-10-01
In this dissertation, the mathematical model of effect of manufacturing errors including microstructure relative height error and relative width error on diffraction efficiency for the harmonic diffractive optical elements (HDEs) is set up. According to the expression of the phase delay and diffraction efficiency of the HDEs, the expression of diffraction efficiency of refraction and diffractive optical element with the microstructure height and periodic width errors in fabrication process is presented in this paper. Furthermore, the effect of manufacturing errors on diffraction efficiency for the harmonic diffractive optical elements is studied, and diffraction efficiency change is analyzed as the relative microstructure height-error in the same and in the opposite sign as well as relative width-error in the same and in the opposite sign. Example including infrared wavelength with materials GE has been discussed in this paper. Two kinds of manufacturing errors applied in 3.7 4.3um middle infrared and 8.7-11.5um far infrared optical system which results in diffraction efficiency and PIDE of HDEs are studied. The analysis results can be used for manufacturing error control in micro-structure height and periodic width. Results can be used for HDEs processing.
Recent Developments in High-Harmonic Fast Wave Physics in NSTX
International Nuclear Information System (INIS)
LeBlanc, B.P.; Bell, R.E.; Bonoli, P.; Harvey, R.; Heidbrink, W.W.; Hosea, J.C.; Kaye, S.M.; Liu, D.; Maingi, R.; Medley, S.S.; Ono, M.; Podesta, M.; Phillips, C.K.; Ryan, P.M.; Roquemore, A.L.; Taylor, G.; Wilson, J.R.
2010-01-01
Understanding the interaction between ion cyclotron range of frequency (ICRF) fast waves and the fast-ions created by neutral beam injection (NBI) is critical for future devices such as ITER, which rely on a combination ICRF and NBI. Experiments in NSTX which use 30 MHz High-Harmonic Fast-Wave (HHFW) ICRF and NBI heating show a competition between electron heating via Landau damping and transit-time magnetic pumping, and radio-frequency wave acceleration of NBI generated fast ions. Understanding and mitigating some of the power loss mechanisms outside the last closed flux surface (LCFS) has resulted in improved HHFW heating inside the LCFS. Nevertheless a significant fraction of the HHFW power is diverted away from the enclosed plasma. Part of this power is observed locally on the divertor. Experimental observations point toward the radio-frequency (RF) excitation of surface waves, which disperse wave power outside the LCFS, as a leading loss mechanism. Lithium coatings lower the density at the antenna, thereby moving the critical density for perpendicular fast-wave propagation away from the antenna and surrounding material surfaces. Visible and infrared imaging reveal flows of RF power along open field lines into the divertor region. In L-mode -- low average NBI power -- conditions, the fast-ion D-alpha (FIDA) diagnostic measures a near doubling and broadening of the density profile of the upper energetic level of the fast ions concurrent with the presence of HHFW power launched with k// = -8m-1. We are able to heat NBI-induced H-mode plasmas with HHFW. The captured power is expected to be split between absorption by the electrons and absorption by the fast ions, based on TORIC calculation. In the case discussed here the Te increases over the whole profile when ∼2MW of HHFW power with antenna k// = 13m-1 is applied after the H-mode transition. But somewhat unexpectedly fast-ion diagnostics do not observe a change between the HHFW heated NBI discharge and the
Bessel harmonic analysis and approximation of functions on the half-line
International Nuclear Information System (INIS)
Platonov, Sergei S
2007-01-01
We study problems of approximation of functions on [0,+∞) in the metric of L p with power weight using generalized Bessel shifts. We prove analogues of direct Jackson theorems for the modulus of smoothness of arbitrary order defined in terms of generalized Bessel shifts. We establish the equivalence of the modulus of smoothness and the K-functional. We define function spaces of Nikol'skii-Besov type and describe them in terms of best approximations. As a tool for approximation, we use a certain class of entire functions of exponential type. In this class, we prove analogues of Bernstein's inequality and others for the Bessel differential operator and its fractional powers. The main tool we use to solve these problems is Bessel harmonic analysis
Non-homogeneous harmonic analysis: 16 years of development
International Nuclear Information System (INIS)
Volberg, A L; Èiderman, V Ya
2013-01-01
This survey contains results and methods in the theory of singular integrals, a theory which has been developing dramatically in the last 15-20 years. The central (although not the only) topic of the paper is the connection between the analytic properties of integrals and operators with Calderón-Zygmund kernels and the geometric properties of the measures. The history is traced of the classical Painlevé problem of describing removable singularities of bounded analytic functions, which has provided a strong incentive for the development of this branch of harmonic analysis. The progress of recent decades has largely been based on the creation of an apparatus for dealing with non-homogeneous measures, and much attention is devoted to this apparatus here. Several open questions are stated, first and foremost in the multidimensional case, where the method of curvature of a measure is not available. Bibliography: 128 titles
Symmetries and Laplacians introduction to harmonic analysis, group representations and applications
Gurarie, D
1992-01-01
Designed as an introduction to harmonic analysis and group representations,this book covers a wide range of topics rather than delving deeply into anyparticular one. In the words of H. Weyl ...it is primarily meant forthe humble, who want to learn as new the things set forth therein, rather thanfor the proud and learned who are already familiar with the subject and merelylook for quick and exact information.... The main objective is tointroduce the reader to concepts, ideas, results and techniques that evolvearound symmetry-groups, representations and Laplacians. Morespecifically, the main interest concerns geometrical objects and structures{X}, discrete or continuous, that possess sufficiently large symmetrygroup G, such as regular graphs (Platonic solids), lattices, andsymmetric Riemannian manifolds. All such objects have a natural Laplacian&Dgr;, a linear operator on functions over X, invariant underthe group action. There are many problems associated with Laplacians onX, such as continuous or discrete...
Numerical analysis of dynamic force spectroscopy using the torsional harmonic cantilever
International Nuclear Information System (INIS)
Solares, Santiago D; Hoelscher, Hendrik
2010-01-01
A spectral analysis method has been recently introduced by Stark et al (2002 Proc. Natl Acad. Sci. USA 99 8473-8) and implemented by Sahin et al (2007 Nat. Nanotechnol. 2 507-14) using a T-shaped cantilever design, the torsional harmonic cantilever (THC), which is capable of performing simultaneous tapping-mode atomic force microscopy imaging and force spectroscopy. Here we report on numerical simulations of the THC system using a simple dual-mass flexural-torsional model, which is applied in combination with Fourier data processing software to illustrate the spectroscopy process for quality factors corresponding to liquid, air and vacuum environments. We also illustrate the acquisition of enhanced topographical images and deformed surface contours under the application of uniform forces, and compare the results to those obtained with a previously reported linear dual-spring-mass model.
Directory of Open Access Journals (Sweden)
Pan Dan-guang
2015-01-01
Full Text Available For realizing the variation of structural dynamic characteristics due to neighbor structure in buildings group, the surface structure is idealized as an equivalent single degree of freedom system with rigid base whose site consists of a single homogeneous layer. Based on the model, a equivalent method on the equivalent seismic excitation is proposed. Then, the differences of seismic response and equivalent seismic input between soil - structure interaction (SSI system and structure -soil-structure interaction (SSSI system are investigated by harmonic analysis. The numerical results show that dynamic responses would be underestimated in SSSI system when the forcing frequencies are close to the Natural frequency if the effects of neighborhood structure were ignored. Neighborhood structure would make the translational displacement increase and rocking vibration decrease. When establishing an effective seismic input, it is necessary to consider the impact of inertia interaction.
Harmonizing electricity markets with physics : real time performance monitoring using grid-3PTM
International Nuclear Information System (INIS)
Budhraja, V.S.
2003-01-01
The Electric Power Group, LLC provides management and strategic consulting services for the electric power industry, with special emphasis on industry restructuring, competitive electricity markets, grid operations and reliability, power technologies, venture investments and start-ups. The Consortium for Electric Reliability Technology Solutions involves national laboratories, universities, and industry partners in researching, developing, and commercializing electric reliability technology solutions to protect and enhance the reliability of the American electric power system under the emerging competitive electricity market structure. Physics differentiate electric markets from other markets: there is real-time balancing, no storage, interconnected network, and power flows governed by physics. Some issues affecting both grid reliability and market issues are difficult to separate, such as security and congestion management, voltage management, reserves, frequency volatility, and others. The author examined the following investment challenges facing the electricity market: grid solutions, market solutions, and technology solutions. The real time performance monitoring and prediction platform, grid-3P was described and applications discussed, such as ACE-frequency monitoring, performance monitoring for automatic generation control (AGC) and frequency response, voltage/VAR monitoring, stability monitoring using phasor technology, and market monitoring. figs
de Souza, Russell J; Zulyniak, Michael A; Desai, Dipika; Shaikh, Mateen R; Campbell, Natalie C; Lefebvre, Diana L; Gupta, Milan; Wilson, Julie; Wahi, Gita; Atkinson, Stephanie A; Teo, Koon K; Subbarao, Padmaja; Becker, Allan B; Mandhane, Piushkumar J; Turvey, Stuart E; Sears, Malcolm R; Anand, Sonia S
2016-11-01
Canada is an ethnically diverse nation, which introduces challenges for health care providers tasked with providing evidence-based dietary advice. We aimed to harmonize food-frequency questionnaires (FFQs) across 4 birth cohorts of ethnically diverse pregnant women to derive robust dietary patterns to investigate maternal and newborn outcomes. The NutriGen Alliance comprises 4 prospective birth cohorts and includes 4880 Canadian mother-infant pairs of predominantly white European [CHILD (Canadian Healthy Infant Longitudinal Development) and FAMILY (Family Atherosclerosis Monitoring In earLY life)], South Asian [START (SouTh Asian birth cohoRT)-Canada], or Aboriginal [ABC (Aboriginal Birth Cohort)] origins. CHILD used a multiethnic FFQ based on a previously validated instrument designed by the Fred Hutchinson Cancer Research Center, whereas FAMILY, START, and ABC used questionnaires specifically designed for use in white European, South Asian, and Aboriginal people, respectively. The serving sizes and consumption frequencies of individual food items within the 4 FFQs were harmonized and aggregated into 36 common food groups. Principal components analysis was used to identify dietary patterns that were internally validated against self-reported vegetarian status and externally validated against a modified Alternative Healthy Eating Index (mAHEI). Three maternal dietary patterns were identified-"plant-based," "Western," and "health-conscious"-which collectively explained 29% of the total variability in eating habits observed in the NutriGen Alliance. These patterns were strongly associated with self-reported vegetarian status (OR: 3.85; 95% CI: 3.47, 4.29; r 2 = 0.30, P < 0.001; for a plant-based diet), and average adherence to the plant-based diet was higher in participants in the fourth quartile of the mAHEI than in the first quartile (mean difference: 46.1%; r 2 = 0.81, P < 0.001). Dietary data collected by using FFQs from ethnically diverse pregnant women can be
Serevina, V.; Muliyati, D.
2018-05-01
This research aims to develop students’ performance assessment instrument based on scientific approach is valid and reliable in assessing the performance of students on basic physics lab of Simple Harmonic Motion (SHM). This study uses the ADDIE consisting of stages: Analyze, Design, Development, Implementation, and Evaluation. The student performance assessment developed can be used to measure students’ skills in observing, asking, conducting experiments, associating and communicate experimental results that are the ‘5M’ stages in a scientific approach. Each grain of assessment in the instrument is validated by the instrument expert and the evaluation with the result of all points of assessment shall be eligible to be used with a 100% eligibility percentage. The instrument is then tested for the quality of construction, material, and language by panel (lecturer) with the result: 85% or very good instrument construction aspect, material aspect 87.5% or very good, and language aspect 83% or very good. For small group trial obtained instrument reliability level of 0.878 or is in the high category, where r-table is 0.707. For large group trial obtained instrument reliability level of 0.889 or is in the high category, where r-table is 0.320. Instruments declared valid and reliable for 5% significance level. Based on the result of this research, it can be concluded that the student performance appraisal instrument based on the developed scientific approach is declared valid and reliable to be used in assessing student skill in SHM experimental activity.
Physical analysis for tribology
International Nuclear Information System (INIS)
Quinn, F.J.
1991-01-01
This textbook by Dr. Quinn contains an interesting and useful combination of subject matter related to tribology and methods of surface analysis pertinent to wear problems. A brief introductory chapter includes a good overview of wear phenomena and mechanisms. Three chapters, comprising about one-third of the book, discuss surface and surface film diagnostic and analysis methods. These include optical, electrical and magnetic techniques as well as electron and x-ray diffraction methods. Considerable detail is provided on background related to crystallography and diffraction. Those not concerned with technique per se, will likely omit these sections. The last five chapters are core subject matter for students, engineers, and researchers interested in wear phenomena. Dr. Quinn draws considerable material from his own extensive background in the area, as well as a good selection of other examples from the research literature
DEFF Research Database (Denmark)
Gautam, Aditya R.; Fulwani, Deepak; Guerrero, Josep M.
2016-01-01
The paper presents a detailed analysis of second order harmonic ripple in a DC microgrid. A boost converter feeding PWM inverter load is considered and equivalent circuit is proposed. The effect of the size of input capacitor, output capacitor and inductor of boost converter, on this ripple has...
Kumar, Rajesh; Grønhaug, Kirsten M.; Romijn, Elisabeth I.; Drogset, Jon O.; Lilledahl, Magnus B.
2014-05-01
Osteoarthritis is one of the most prevalent joint diseases in the world. Although the cause of osteoarthritis is not exactly clear, the disease results in a degradation of the quality of the articular cartilage including collagen and other extracellular matrix components. We have investigated alterations in the structure of collagen fibers in the cartilage tissue of the human knee using mulitphoton microscopy. Due to inherent high nonlinear susceptibility, ordered collagen fibers present in the cartilage tissue matrix produces strong second harmonic generation (SHG) signals. Significant morphological differences are found in different Osteoarthritic grades of cartilage by SHG microscopy. Based on the polarization analysis of the SHG signal, we find that a few locations of hyaline cartilage (mainly type II collagen) is being replaced by fibrocartilage (mainly type I cartilage), in agreement with earlier literature. To locate the different types and quantify the alteration in the structure of collagen fiber, we employ polarization-SHG microscopic analysis, also referred to as _-tensor imaging. The image analysis of p-SHG image obtained by excitation polarization measurements would represent different tissue constituents with different numerical values at pixel level resolution.
Full-Band Quasi-Harmonic Analysis and Synthesis of Musical Instrument Sounds with Adaptive Sinusoids
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Marcelo Caetano
2016-05-01
Full Text Available Sinusoids are widely used to represent the oscillatory modes of musical instrument sounds in both analysis and synthesis. However, musical instrument sounds feature transients and instrumental noise that are poorly modeled with quasi-stationary sinusoids, requiring spectral decomposition and further dedicated modeling. In this work, we propose a full-band representation that fits sinusoids across the entire spectrum. We use the extended adaptive Quasi-Harmonic Model (eaQHM to iteratively estimate amplitude- and frequency-modulated (AM–FM sinusoids able to capture challenging features such as sharp attacks, transients, and instrumental noise. We use the signal-to-reconstruction-error ratio (SRER as the objective measure for the analysis and synthesis of 89 musical instrument sounds from different instrumental families. We compare against quasi-stationary sinusoids and exponentially damped sinusoids. First, we show that the SRER increases with adaptation in eaQHM. Then, we show that full-band modeling with eaQHM captures partials at the higher frequency end of the spectrum that are neglected by spectral decomposition. Finally, we demonstrate that a frame size equal to three periods of the fundamental frequency results in the highest SRER with AM–FM sinusoids from eaQHM. A listening test confirmed that the musical instrument sounds resynthesized from full-band analysis with eaQHM are virtually perceptually indistinguishable from the original recordings.
Bin, Che; Ruoying, Yu; Dongsheng, Dang; Xiangyan, Wang
2017-05-01
Distributed Generation (DG) integrating to the network would cause the harmonic pollution which would cause damages on electrical devices and affect the normal operation of power system. On the other hand, due to the randomness of the wind and solar irradiation, the output of DG is random, too, which leads to an uncertainty of the harmonic generated by the DG. Thus, probabilistic methods are needed to analyse the impacts of the DG integration. In this work we studied the harmonic voltage probabilistic distribution and the harmonic distortion in distributed network after the distributed photovoltaic (DPV) system integrating in different weather conditions, mainly the sunny day, cloudy day, rainy day and the snowy day. The probabilistic distribution function of the DPV output power in different typical weather conditions could be acquired via the parameter identification method of maximum likelihood estimation. The Monte-Carlo simulation method was adopted to calculate the probabilistic distribution of harmonic voltage content at different frequency orders as well as the harmonic distortion (THD) in typical weather conditions. The case study was based on the IEEE33 system and the results of harmonic voltage content probabilistic distribution as well as THD in typical weather conditions were compared.
Non-Characteristic Harmonics Analysis of the ITER Pulsed Power Supply
International Nuclear Information System (INIS)
Yang Wei; Xu Liuwei; Fu Peng; Lu Huawei; Sheng Zhicai
2009-01-01
The ITER pulsed power supply system will be operated in non-ideal conditions including an asymmetric firing angle, an unbalanced AC supply and an unbalanced AC side impedance of the transformer. In this study the switching functions approach is used to calculate non-characteristic harmonics in ITER, possibly caused by an AC-DC convertor in non-ideal conditions. A PSCAD simulation model is set up to study the non-characteristic harmonics in those non-ideal conditions. It is found that the non-characteristic harmonic does appear and the simulation result is in accordance with the calculating strategy. (fusion engineering)
Harmonic analysis for the characterization and correction of geometric distortion in MRI.
Tadic, Tony; Jaffray, David A; Stanescu, Teodor
2014-11-01
Magnetic resonance imaging (MRI) is gaining widespread use in radiation therapy planning, patient setup verification, and real-time guidance of radiation delivery. Successful implementation of these technologies relies on the development of simple and efficient methods to characterize and monitor the geometric distortions arising due to system imperfections and gradient nonlinearities. To this end, the authors present the theory and validation of a novel harmonic approach to the quantification of system-related distortions in MRI. The theory of spatial encoding in MRI is applied to demonstrate that the 3D distortion vector field (DVF) is given by the solution of a second-order boundary value problem (BVP). This BVP is comprised of Laplace's equation and a limited measurement of the distortion on the boundary of a specified region of interest (ROI). An analytical series expansion solving this BVP within a spherical ROI is obtained, and a statistical uncertainty analysis is performed to determine how random errors in the boundary measurements propagate to the ROI interior. This series expansion is then evaluated to obtain volumetric DVF mappings that are compared to reference data obtained on a 3 T full-body scanner. This validation is performed within two spheres of 20 cm diameter (one centered at the scanner origin and the other offset +3 cm along each of the transverse directions). Initially, a high-order mapping requiring measurements at 5810 boundary points is used. Then, after exploring the impact of the boundary sampling density and the effect of series truncation, a reduced-order mapping requiring measurements at 302 boundary points is evaluated. The volumetric DVF mappings obtained from the harmonic analysis are in good agreement with the reference data. Following distortion correction using the high-order mapping, the authors estimate a reduction in the mean distortion magnitude from 0.86 to 0.42 mm and from 0.93 to 0.39 mm within the central and offset
Harmonic analysis for the characterization and correction of geometric distortion in MRI
International Nuclear Information System (INIS)
Tadic, Tony; Stanescu, Teodor; Jaffray, David A.
2014-01-01
Purpose: Magnetic resonance imaging (MRI) is gaining widespread use in radiation therapy planning, patient setup verification, and real-time guidance of radiation delivery. Successful implementation of these technologies relies on the development of simple and efficient methods to characterize and monitor the geometric distortions arising due to system imperfections and gradient nonlinearities. To this end, the authors present the theory and validation of a novel harmonic approach to the quantification of system-related distortions in MRI. Methods: The theory of spatial encoding in MRI is applied to demonstrate that the 3D distortion vector field (DVF) is given by the solution of a second-order boundary value problem (BVP). This BVP is comprised of Laplace’s equation and a limited measurement of the distortion on the boundary of a specified region of interest (ROI). An analytical series expansion solving this BVP within a spherical ROI is obtained, and a statistical uncertainty analysis is performed to determine how random errors in the boundary measurements propagate to the ROI interior. This series expansion is then evaluated to obtain volumetric DVF mappings that are compared to reference data obtained on a 3 T full-body scanner. This validation is performed within two spheres of 20 cm diameter (one centered at the scanner origin and the other offset +3 cm along each of the transverse directions). Initially, a high-order mapping requiring measurements at 5810 boundary points is used. Then, after exploring the impact of the boundary sampling density and the effect of series truncation, a reduced-order mapping requiring measurements at 302 boundary points is evaluated. Results: The volumetric DVF mappings obtained from the harmonic analysis are in good agreement with the reference data. Following distortion correction using the high-order mapping, the authors estimate a reduction in the mean distortion magnitude from 0.86 to 0.42 mm and from 0.93 to 0.39 mm
Computational-Model-Based Analysis of Context Effects on Harmonic Expectancy.
Morimoto, Satoshi; Remijn, Gerard B; Nakajima, Yoshitaka
2016-01-01
Expectancy for an upcoming musical chord, harmonic expectancy, is supposedly based on automatic activation of tonal knowledge. Since previous studies implicitly relied on interpretations based on Western music theory, the underlying computational processes involved in harmonic expectancy and how it relates to tonality need further clarification. In particular, short chord sequences which cannot lead to unique keys are difficult to interpret in music theory. In this study, we examined effects of preceding chords on harmonic expectancy from a computational perspective, using stochastic modeling. We conducted a behavioral experiment, in which participants listened to short chord sequences and evaluated the subjective relatedness of the last chord to the preceding ones. Based on these judgments, we built stochastic models of the computational process underlying harmonic expectancy. Following this, we compared the explanatory power of the models. Our results imply that, even when listening to short chord sequences, internally constructed and updated tonal assumptions determine the expectancy of the upcoming chord.
Orthogonal Projection-Based Harmonic Signal Removal for Operational Modal Analysis
DEFF Research Database (Denmark)
Gres, Szymon; Andersen, Palle; Hoen, C.
2019-01-01
A presence of a high amplitude periodic signals in the output responses from operating structures often pose a challenge for output-only system identification and, in case of health monitoring, damage detection/localization methods. This paper introduces a pre-processing approach that removes...... the harmonic part from the output signals directly in the time domain. The new method uses orthogonal projections of the harmonic realization of the signal onto the raw time series within the stochastic subspace framework. Proposed algorithm is tested on two experimental examples. First, an aluminum plate...... excited with both random white and periodic excitations. Second, a full-scale industrial case of a ferry excited by a random environmental load with harmonic interference from a rotating machinery on-board. In both cases the proposed method removes the harmonics from the structural responses while leaving...
Multidimensional high harmonic spectroscopy
International Nuclear Information System (INIS)
Bruner, Barry D; Soifer, Hadas; Shafir, Dror; Dudovich, Nirit; Serbinenko, Valeria; Smirnova, Olga
2015-01-01
High harmonic generation (HHG) has opened up a new frontier in ultrafast science where attosecond time resolution and Angstrom spatial resolution are accessible in a single measurement. However, reconstructing the dynamics under study is limited by the multiple degrees of freedom involved in strong field interactions. In this paper we describe a new class of measurement schemes for resolving attosecond dynamics, integrating perturbative nonlinear optics with strong-field physics. These approaches serve as a basis for multidimensional high harmonic spectroscopy. Specifically, we show that multidimensional high harmonic spectroscopy can measure tunnel ionization dynamics with high precision, and resolves the interference between multiple ionization channels. In addition, we show how multidimensional HHG can function as a type of lock-in amplifier measurement. Similar to multi-dimensional approaches in nonlinear optical spectroscopy that have resolved correlated femtosecond dynamics, multi-dimensional high harmonic spectroscopy reveals the underlying complex dynamics behind attosecond scale phenomena. (paper)
HARMONICS ANALYSIS OF SYSTEM USING SHUNT ACTIVE POWER FILTER BY MATLAB SIMULATION
VAISHALI PARDHI; Dr.A K KORI
2017-01-01
The widely use of nonlinear loads, such as diode and thyristor, rectifiers, computers, consumer electronics, uninterruptible power supplies and adjustable speed drives results in the distorted current waveforms in the electrical distribution systems. Harmonics is a major problem in power systems that have become serious recently owing to the wide use of power electronics-related equipment. The input power factor of most of these equipments is poor. There is a great need to reduce these harmon...
Computational-Model-Based Analysis of Context Effects on Harmonic Expectancy
Morimoto, Satoshi; Remijn, Gerard B.; Nakajima, Yoshitaka
2016-01-01
Expectancy for an upcoming musical chord, harmonic expectancy, is supposedly based on automatic activation of tonal knowledge. Since previous studies implicitly relied on interpretations based on Western music theory, the underlying computational processes involved in harmonic expectancy and how it relates to tonality need further clarification. In particular, short chord sequences which cannot lead to unique keys are difficult to interpret in music theory. In this study, we examined effects ...
Energy Technology Data Exchange (ETDEWEB)
Eliazar, Iddo, E-mail: eliazar@post.tau.ac.il
2017-05-15
The exponential, the normal, and the Poisson statistical laws are of major importance due to their universality. Harmonic statistics are as universal as the three aforementioned laws, but yet they fall short in their ‘public relations’ for the following reason: the full scope of harmonic statistics cannot be described in terms of a statistical law. In this paper we describe harmonic statistics, in their full scope, via an object termed harmonic Poisson process: a Poisson process, over the positive half-line, with a harmonic intensity. The paper reviews the harmonic Poisson process, investigates its properties, and presents the connections of this object to an assortment of topics: uniform statistics, scale invariance, random multiplicative perturbations, Pareto and inverse-Pareto statistics, exponential growth and exponential decay, power-law renormalization, convergence and domains of attraction, the Langevin equation, diffusions, Benford’s law, and 1/f noise. - Highlights: • Harmonic statistics are described and reviewed in detail. • Connections to various statistical laws are established. • Connections to perturbation, renormalization and dynamics are established.
International Nuclear Information System (INIS)
Eliazar, Iddo
2017-01-01
The exponential, the normal, and the Poisson statistical laws are of major importance due to their universality. Harmonic statistics are as universal as the three aforementioned laws, but yet they fall short in their ‘public relations’ for the following reason: the full scope of harmonic statistics cannot be described in terms of a statistical law. In this paper we describe harmonic statistics, in their full scope, via an object termed harmonic Poisson process: a Poisson process, over the positive half-line, with a harmonic intensity. The paper reviews the harmonic Poisson process, investigates its properties, and presents the connections of this object to an assortment of topics: uniform statistics, scale invariance, random multiplicative perturbations, Pareto and inverse-Pareto statistics, exponential growth and exponential decay, power-law renormalization, convergence and domains of attraction, the Langevin equation, diffusions, Benford’s law, and 1/f noise. - Highlights: • Harmonic statistics are described and reviewed in detail. • Connections to various statistical laws are established. • Connections to perturbation, renormalization and dynamics are established.
Mapping the total electron content over Malaysia using Spherical Cap Harmonic Analysis
Bahari, S.; Abdullah, M.; Bouya, Z.; Musa, T. A.
2017-12-01
The ionosphere over Malaysia is unique because of her location which is in close proximity to the geomagnetic equator and is in the equatorial regions. In this region, the magnetic field is horizontally oriented from south to north and field aligned direction is in the meridional plane (ExB) which becomes the source of equatorial ionospheric anomaly occurrence such as plasma bubble, fountain effects and others. Until today, there is no model that has been developed over Malaysia to study the ionosphere. Due to that, the main objective of this paper is to develop a new technique for mapping the total electron content (TEC) from GPS measurements. Data by myRTKnet network of GPS receiver over Malaysia were used in this study. A new methodology, based on modified spherical cap harmonic analysis (SCHA), was developed to estimate diurnal vertical TEC over the region using GPS observations. The SCHA model is based on longitudinal expansion in Fourier series and fractional Legendre co-latitudinal functions over a spherical cap-like region. The TEC map with spatial resolution of 0.15 ° x 0.15 ° in latitude and longitude with the time resolution of 30 seconds are derived. TEC maps from the SCHA model were compared with the global ionospheric map and other regional models. Result shows that during low solar activity, SCHA model had a better mapping with the accuracy of less than 1 TECU compared to other regional models.
Harne, Ryan L.; Goodpaster, Benjamin A.
2018-01-01
Structural components susceptible to adverse, post-buckled dynamic behaviors have long challenged the success of applications requiring lightweight, slender curved structures, while researchers have begun to leverage such bistable systems in emerging applications for novel energy attenuation and shape-changing properties. To expedite development and deployment of these built-up platforms containing post-buckled constituents, efficient approaches are required to complement time-consuming full-field models in the prediction of the near- and far-from-equilibrium dynamics. This research meets the need by introducing a semi-analytical model framework to enable the characterization of steady-state responses in multi degree-of-freedom (DOF) and multistable structural systems subjected to harmonic excitation. In so doing, the pathway for assessing impedance measures is created here so as to identify how energy travels and returns within built-up multistable structures. Verified by simulations and qualitatively validated by experiments, the analysis is shown to accurately reproduce both near- and far-from-equilibrium responses including different classes of energetic snap-through dynamics that only exist in such multistable structures. A first look at the impedance measures of different dynamic regimes reveals a connection between damping in multistable structures and the sustainability of far-from-equilibrium oscillations.
International Nuclear Information System (INIS)
Viano, G.A.
1980-01-01
The harmonic analysis of the elastic scattering amplitude F(s,t) of two spinless particles, at fixed t<0, is here revisited using the non-euclidean Fourier analysis in the sense of Helgason, and the approach of Ehrenpresis to the special functions. With these techniques it is possible to derive the Fourier and Laplace transforms for the scattering amplitude. Indeed these transforms are obtained by projecting the amplitude on functions which play a role similar to that played by the exponentials on the real line; here we show how to construct these functions, using essentially geometrical tools. Since the harmonic analysis is a decomposition which separates the dynamics from the symmetry of the problem, we obtain an explicit geometrical characterization of those terms which reflect the symmetry
Directory of Open Access Journals (Sweden)
Wolf Tamir
2011-08-01
Full Text Available Abstract Background Monopolar cautery is the most commonly used surgical cutting and hemostatic tool for head and neck surgery. There are newer technologies that are being utilized with the goal of precise cutting, decreasing blood loss, reducing thermal damage, and allowing faster wound healing. Our study compares thermal damage caused by Harmonic scalpel and CO2 laser to cadaveric tongue. Methods Two fresh human cadaver heads were enrolled for the study. Oral tongue was exposed and incisions were made in the tongue akin to a tongue tumor resection using the harmonic scalpel and flexible C02 laser fiber at various settings recommended for surgery. The margins of resection were sampled, labeled, and sent for pathological analysis to assess depth of thermal damage calculated in millimeters. The pathologist was blinded to the surgical tool used. Control tongue tissue was also sent for comparison as a baseline for comparison. Results Three tongue samples were studied to assess depth of thermal damage by harmonic scalpel. The mean depth of thermal damage was 0.69 (range, 0.51 - 0.82. Five tongue samples were studied to assess depth of thermal damage by CO2 laser. The mean depth of thermal damage was 0.3 (range, 0.22 to 0.43. As expected, control samples showed 0 mm of thermal damage. There was a statistically significant difference between the depth of thermal injury to tongue resection margins by harmonic scalpel as compared to CO2 laser, (p = 0.003. Conclusion In a cadaveric model, flexible CO2 laser fiber causes less depth of thermal damage when compared with harmonic scalpel at settings utilized in our study. However, the relevance of this information in terms of wound healing, hemostasis, safety, cost-effectiveness, and surgical outcomes needs to be further studied in clinical settings.
Harmonic Stability and Resonance Analysis in Large PMSG-Based Wind Power Plants
DEFF Research Database (Denmark)
Ebrahimzadeh, Esmaeil; Blaabjerg, Frede; Wang, Xiongfei
2018-01-01
Compared to the conventional power systems, large Wind Power Plants (WPPs) present a more challenging system where the interactions between the passive elements and the wideband control systems of power converters may result in harmonic instability and new resonance frequencies. Most of researches...... system and the resonance frequencies are identified based on the element amplitudes of the MIMO matrix. An active damping controller is used to set the poles of the WPP in a desired location in order to mitigate the harmonic instability problems. Multiple case studies are provided to depict that Wind...
A Perturbation Analysis of Harmonics Generation from Saturated Elements in Power Systems
Kumano, Teruhisa
Nonlinear phenomena such as saturation in magnetic flux give considerable effects in power system analysis. It is reported that a failure in a real 500kV system triggered islanding operation, where resultant even harmonics caused malfunctions in protective relays. It is also reported that the major origin of this wave distortion is nothing but unidirectional magnetization of the transformer iron core. Time simulation is widely used today to analyze this type of phenomena, but it has basically two shortcomings. One is that the time simulation takes two much computing time in the vicinity of inflection points in the saturation characteristic curve because certain iterative procedure such as N-R (Newton-Raphson) should be used and such methods tend to be caught in an ill conditioned numerical hunting. The other is that such simulation methods sometimes do not help intuitive understanding of the studied phenomenon because the whole nonlinear equations are treated in a matrix form and not properly divided into understandable parts as done in linear systems. This paper proposes a new computation scheme which is based on so called perturbation method. Magnetic saturation in iron cores in a generator and a transformer are taken into account. The proposed method has a special feature against the first shortcoming of the N-R based time simulation method stated above. In the proposed method no iterative process is used to reduce the equation residue but uses perturbation series, which means free from the ill condition problem. Users have only to calculate each perturbation terms one by one until he reaches necessary accuracy. In a numerical example treated in the present paper the first order perturbation can make reasonably high accuracy, which means very fast computing. In numerical study three nonlinear elements are considered. Calculated results are almost identical to the conventional Newton-Raphson based time simulation, which shows the validity of the method. The
Energy Technology Data Exchange (ETDEWEB)
Cryns, Jackson W.; Hatchell, Brian K.; Santiago-Rojas, Emiliano; Silvers, Kurt L.
2013-07-01
Formal journal article Experimental analysis of a piezoelectric energy harvesting system for harmonic, random, and sine on random vibration Abstract: Harvesting power with a piezoelectric vibration powered generator using a full-wave rectifier conditioning circuit is experimentally compared for varying sinusoidal, random and sine on random (SOR) input vibration scenarios. Additionally, the implications of source vibration characteristics on harvester design are discussed. Studies in vibration harvesting have yielded numerous alternatives for harvesting electrical energy from vibrations but piezoceramics arose as the most compact, energy dense means of energy transduction. The rise in popularity of harvesting energy from ambient vibrations has made piezoelectric generators commercially available. Much of the available literature focuses on maximizing harvested power through nonlinear processing circuits that require accurate knowledge of generator internal mechanical and electrical characteristics and idealization of the input vibration source, which cannot be assumed in general application. In this manuscript, variations in source vibration and load resistance are explored for a commercially available piezoelectric generator. We characterize the source vibration by its acceleration response for repeatability and transcription to general application. The results agree with numerical and theoretical predictions for in previous literature that load optimal resistance varies with transducer natural frequency and source type, and the findings demonstrate that significant gains are seen with lower tuned transducer natural frequencies for similar source amplitudes. Going beyond idealized steady state sinusoidal and simplified random vibration input, SOR testing allows for more accurate representation of real world ambient vibration. It is shown that characteristic interactions from more complex vibrational sources significantly alter power generation and power processing
Tuvan Throat Singing and Harmonics
Ruiz, Michael J.; Wilken, David
2018-01-01
Tuvan throat singing, also called overtone singing, provides for an exotic demonstration of the physics of harmonics as well as introducing an Asian musical aesthetic. A low fundamental is sung and the singer skillfully alters the resonances of the vocal system to enhance an overtone (harmonic above the fundamental). The result is that the…
Data-adaptive harmonic analysis and prediction of sea level change in North Atlantic region
Kondrashov, D. A.; Chekroun, M.
2017-12-01
This study aims to characterize North Atlantic sea level variability across the temporal and spatial scales. We apply recently developed data-adaptive Harmonic Decomposition (DAH) and Multilayer Stuart-Landau Models (MSLM) stochastic modeling techniques [Chekroun and Kondrashov, 2017] to monthly 1993-2017 dataset of Combined TOPEX/Poseidon, Jason-1 and Jason-2/OSTM altimetry fields over North Atlantic region. The key numerical feature of the DAH relies on the eigendecomposition of a matrix constructed from time-lagged spatial cross-correlations. In particular, eigenmodes form an orthogonal set of oscillating data-adaptive harmonic modes (DAHMs) that come in pairs and in exact phase quadrature for a given temporal frequency. Furthermore, the pairs of data-adaptive harmonic coefficients (DAHCs), obtained by projecting the dataset onto associated DAHMs, can be very efficiently modeled by a universal parametric family of simple nonlinear stochastic models - coupled Stuart-Landau oscillators stacked per frequency, and synchronized across different frequencies by the stochastic forcing. Despite the short record of altimetry dataset, developed DAH-MSLM model provides for skillful prediction of key dynamical and statistical features of sea level variability. References M. D. Chekroun and D. Kondrashov, Data-adaptive harmonic spectra and multilayer Stuart-Landau models. HAL preprint, 2017, https://hal.archives-ouvertes.fr/hal-01537797
Analysis and Damping of Harmonic Propagation in DG-Penetrated Distribution Networks
DEFF Research Database (Denmark)
Lu, Jinghang; Savaghebi, Mehdi; Guerrero, Josep M.
2016-01-01
With the increasing penetration of nonlinear loads into distribution system, stable operation of power distribution system suffers challenge by harmonic voltage propagation and resonance amplification which is also known as whack-a-mole phenomenon. However, until now this phenomenon has not been...
International Nuclear Information System (INIS)
Fiske, David R
2006-01-01
Computing spherical harmonic decompositions is a ubiquitous technique that arises in a wide variety of disciplines and a large number of scientific codes. Because spherical harmonics are defined by integrals over spheres, however, one must perform some sort of interpolation in order to compute them when data are stored on a cubic lattice. Misner (2004 Class. Quantum Grav. 21 S243) presented a novel algorithm for computing the spherical harmonic components of data represented on a cubic grid, which has been found in real applications to be both efficient and robust to the presence of mesh refinement boundaries. At the same time, however, practical applications of the algorithm require knowledge of how the truncation errors of the algorithm depend on the various parameters in the algorithm. Based on analytic arguments and experience using the algorithm in real numerical simulations, I explore these dependences and provide a rule of thumb for choosing the parameters based on the truncation errors of the underlying data. I also demonstrate that symmetries in the spherical harmonics themselves allow for an even more efficient implementation of the algorithm than was suggested by Misner in his original paper
Physics Analysis Tools Workshop Report
Assamagan, K A
A Physics Analysis Tools (PAT) workshop was held at the University of Tokyo in Tokyo Japan on May 15-19, 2006. Unlike the previous ones, this workshop brought together the core PAT developers and ATLAS users. The workshop was attended by 69 people from various institutions: Australia 5 Canada 1 China 6 CERN 4 Europe 7 Japan 32 Taiwan 3 USA 11 The agenda consisted of a 2-day tutorial for users, a 0.5-day user feedback discussion session between users and developers, and a 2-day core PAT workshop devoted to issues in Physics Analysis Tools activities. The tutorial, attended by users and developers, covered the following grounds: Event Selection with the TAG Event Selection Using the Athena-Aware NTuple Event Display Interactive Analysis within ATHENA Distributed Analysis Monte Carlo Truth Tools Trigger-Aware Analysis Event View By many accounts, the tutorial was useful. This workshop was the first time that the ATLAS Asia-Pacific community (Taiwan, Japan, China and Australia) go...
Directory of Open Access Journals (Sweden)
Akhmad Yusuf
2017-12-01
Full Text Available Panggon Lunjak (trampoline is one of the famous amusement parks among the people that we can use as a recreation to enjoy a pleasant sensation. Without us knowing the amusement park that we often encounter is actually the result of the application of science and technology, especially in the field of physics, because it is amusement park for student of science is a real laboratory or the giant laboratory that we can use as a study of physics concepts and as research materials. Panggon Lunjak (trampoline motion is very close to the harmonic motion where the resulting graph of the sinus so that on the graph will be in the analysis of kinematics and energy phenomena, so that research on simple harmonic motion materials is not limited to research using pendulum motion and spring load motion which is often exemplified as research on harmonic motion. The purpose of this study is to analyze the physical aspects of Panggon Lunjak (trampoline motion based on the laws of physics on the concept of kinematics and analyze energy, Where the mechanical energy of addition between potential energy and kinetic energy (Conservation of energy. The analysis is done by using video tracking. Based on the analysis done using people as a mass, the result of the amplitude, the spring constant, angular frequency, and the law of conservation of energy on the Panggon Lunjak (trampoline is true. This analysis activity will be well used as a physics learning for students.
Physics Analysis Tools Workshop 2007
Elizabeth Gallas,
The ATLAS PAT (Physics Analysis Tools) group evaluates, develops and tests software tools for the analysis of physics data, consistent with the ATLAS analysis and event data models. Following on from earlier PAT workshops in London (2004), Tucson (2005) and Tokyo (2006), this year's workshop was hosted by the University of Bergen in Norway on April 23-28 with more than 60 participants. The workshop brought together PAT developers and users to discuss the available tools with an emphasis on preparing for data taking. At the start of the week, workshop participants, laptops and power converters in-hand, jumped headfirst into tutorials, learning how to become trigger-aware and how to use grid computing resources via the distributed analysis tools Panda and Ganga. The well organised tutorials were well attended and soon the network was humming, providing rapid results to the users and ample feedback to the developers. A mid-week break was provided by a relaxing and enjoyable cruise through the majestic Norwegia...
Zhao, Dan; Wang, Xiaoman; Cheng, Yuan; Liu, Shaogang; Wu, Yanhong; Chai, Liqin; Liu, Yang; Cheng, Qianju
2018-05-01
Piecewise-linear structure can effectively broaden the working frequency band of the piezoelectric energy harvester, and improvement of its research can promote the practical process of energy collection device to meet the requirements for powering microelectronic components. In this paper, the incremental harmonic balance (IHB) method is introduced for the complicated and difficult analysis process of the piezoelectric energy harvester to solve these problems. After obtaining the nonlinear dynamic equation of the single-degree-of-freedom piecewise-linear energy harvester by mathematical modeling and the equation is solved based on the IHB method, the theoretical amplitude-frequency curve of open-circuit voltage is achieved. Under 0.2 g harmonic excitation, a piecewise-linear energy harvester is experimentally tested by unidirectional frequency-increasing scanning. The results demonstrate that the theoretical and experimental amplitudes have the same trend, and the width of the working band with high voltage output are 4.9 Hz and 4.7 Hz, respectively, and the relative error is 4.08%. The open-output peak voltage are 21.53 V and 18.25 V, respectively, and the relative error is 15.23%. Since the theoretical value is consistent with the experimental results, the theoretical model and the incremental harmonic balance method used in this paper are suitable for solving single-degree-of-freedom piecewise-linear piezoelectric energy harvester and can be applied to further parameter optimized design.
Wen, Lianggong
Many diseases, e.g. ovarian cancer, breast cancer and pulmonary fibrosis, are commonly associated with drastic alterations in surrounding connective tissue, and changes in the extracellular matrix (ECM) are associated with the vast majority of cellular processes in disease progression and carcinogenesis: cell differentiation, proliferation, biosynthetic ability, polarity, and motility. We use second harmonic generation (SHG) microscopy for imaging the ECM because it is a non-invasive, non-linear laser scanning technique with high sensitivity and specificity for visualizing fibrillar collagen. In this thesis, we are interested in developing imaging techniques to understand how the ECM, especially the collagen architecture, is remodeled in diseases. To quantitate remodeling, we implement a 3D texture analysis to delineate the collagen fibrillar morphology observed in SHG microscopy images of human normal and high grade malignant ovarian tissues. In the learning stage, a dictionary of "textons"---frequently occurring texture features that are identified by measuring the image response to a filter bank of various shapes, sizes, and orientations---is created. By calculating a representative model based on the texton distribution for each tissue type using a training set of respective mages, we then perform classification between normal and high grade malignant ovarian tissues classification based on the area under receiver operating characteristic curves (true positives versus false positives). The local analysis algorithm is a more general method to probe rapidly changing fibrillar morphologies than global analyses such as FFT. It is also more versatile than other texture approaches as the filter bank can be highly tailored to specific applications (e.g., different disease states) by creating customized libraries based on common image features. Further, we describe the development of a multi-view 3D SHG imaging platform. Unlike fluorescence microscopy, SHG excites
International Nuclear Information System (INIS)
Galperin, A.; Ivanov, E.; Ogievetsky, V.; Sokatchev, E.
1985-01-01
This paper completes a descrption of the quantization procedure in the harmonic superspace approach. The Feynman rules for N=2 matter and Yang-Mills theories are derived and the various examples of harmonic supergraph calculations are given. Calculations appear to be not more difficult than those in the N=1 case. The integration over harmonic variables does not lead to any troubles, a non-locality in these disappears on-shell. The important property is that the quantum corrections are always writen as integrals over the full harmonic superspace even though the initial action is an integral over the analytic subspace. As a by-product our results imply a very simple proof of finiteness of a wide class of the N=4, d=2 non-linear Σ-models. The most general self-couplings of hypermultiplets including those with broken SU(2) are considered.The duality relations among the N=2 linear multiplet and both kinds of hypermultiplet are established
Analysis of the harmonic and intermodulation distortion in a multimode fiber optic link.
Gasulla, I; Capmany, J
2007-07-23
We present an analytical evaluation of the harmonic and the intermodulation distortion effects produced in the transmission of an analog signal composed of various RF tones through a multimode fiber link. It is based on the electric field propagation model previously published by the authors. Results show the possibility of implementing subcarrier multiplexing techniques (SCM) with Composite Second Order (CSO) values below -50 dBc over short and middle reach multimode fiber links.
Physics: A New Reactor Physics Analysis Toolkit
International Nuclear Information System (INIS)
Rabiti, C.; Wang, Y.; Palmiotti, G.; Hiruta, H.; Cogliati, J.; Alfonsi, A.
2011-01-01
In the last year INL has internally pursued the development of a new reactor analysis tool: PHISICS. The software is built in a modular approach to simplify the independent development of modules by different teams and future maintenance. Most of the modules at the time of this summary are still under development (time dependent transport driver, depletion, cross section I/O and interpolation, generalized perturbation theory), while the transport solver INSTANT (Intelligent Nodal and Semi-structured Treatment for Advanced Neutron Transport) has already been widely used1, 2, 3, 4. For this reason we will focus mainly on the presentation of the transport solver INSTANT
Experiment Design and Analysis Guide - Neutronics & Physics
Energy Technology Data Exchange (ETDEWEB)
Misti A Lillo
2014-06-01
The purpose of this guide is to provide a consistent, standardized approach to performing neutronics/physics analysis for experiments inserted into the Advanced Test Reactor (ATR). This document provides neutronics/physics analysis guidance to support experiment design and analysis needs for experiments irradiated in the ATR. This guide addresses neutronics/physics analysis in support of experiment design, experiment safety, and experiment program objectives and goals. The intent of this guide is to provide a standardized approach for performing typical neutronics/physics analyses. Deviation from this guide is allowed provided that neutronics/physics analysis details are properly documented in an analysis report.
Bennett, Charles L [Livermore, CA
2009-10-20
A high efficiency harmonic engine based on a resonantly reciprocating piston expander that extracts work from heat and pressurizes working fluid in a reciprocating piston compressor. The engine preferably includes harmonic oscillator valves capable of oscillating at a resonant frequency for controlling the flow of working fluid into and out of the expander, and also preferably includes a shunt line connecting an expansion chamber of the expander to a buffer chamber of the expander for minimizing pressure variations in the fluidic circuit of the engine. The engine is especially designed to operate with very high temperature input to the expander and very low temperature input to the compressor, to produce very high thermal conversion efficiency.
On Aggregation Requirements for Harmonic Stability Analysis in Wind Power Plants
DEFF Research Database (Denmark)
Dowlatabadi, Mohammadkazem Bakhshizadeh; Hjerrild, Jesper; Kocewiak, Łukasz
2017-01-01
In harmonic stability studies, stable operation of a power system must be ensured at any possible configuration. This leads to a large number of cases due to the high number of components in a power system. An aggregated model can be used to lower the complexity and to reduce the number...... of different cases. In other words, several similar converters (e.g. Wind Turbine Generators) can be replaced by a converter with larger ratings. In most cases, aggregated models work well for stability studies, however, in some cases the aggregation might result in a wrong evaluation of stability...
Partial Fourier analysis of time-harmonic Maxwell's equations in axisymmetric domains
International Nuclear Information System (INIS)
Nkemzi, Boniface
2003-01-01
We analyze the Fourier method for treating time-harmonic Maxwell's equations in three-dimensional axisymmetric domains with non-axisymmetric data. The Fourier method reduces the three-dimensional boundary value problem to a system of decoupled two-dimensional boundary value problems on the plane meridian domain of the axisymmetric domain. The reduction process is fully described and suitable weighted spaces are introduced on the meridian domain to characterize the two-dimensional solutions. In particular, existence and uniqueness of solutions of the two-dimensional problems is proved and a priori estimates for the solutions are given. (author)
Tuvan throat singing and harmonics
Ruiz, Michael J.; Wilken, David
2018-05-01
Tuvan throat singing, also called overtone singing, provides for an exotic demonstration of the physics of harmonics as well as introducing an Asian musical aesthetic. A low fundamental is sung and the singer skillfully alters the resonances of the vocal system to enhance an overtone (harmonic above the fundamental). The result is that the listener hears two pitches simultaneously. Harmonics such as H8, H9, H10, and H12 form part of a pentatonic scale and are commonly selected for melody tones by Tuvan singers. A real-time spectrogram is provided in a video (Ruiz M J 2018 Video: Tuvan Throat Singing and Harmonics http://mjtruiz.com/ped/tuva/) so that Tuvan harmonics can be visualized as they are heard.
Tides and tidal harmonics at Umbharat, Gujarat
Digital Repository Service at National Institute of Oceanography (India)
Suryanarayana, A.; Swamy, G.N.
A part of the data on tides recorded at Machiwada near Umbharat, Gulf of Cambay during April 1978 was subjected to harmonic analysis following the Admiralty procedure. The general tidal characteristics and the value of four major harmonic...
Spherical harmonics analysis of Fermi gamma-ray data and the Galactic dark matter halo
International Nuclear Information System (INIS)
Malyshev, Dmitry; Bovy, Jo; Cholis, Ilias
2011-01-01
We argue that the decomposition of gamma-ray maps in spherical harmonics is a sensitive tool to study dark matter (DM) annihilation or decay in the main Galactic halo of the Milky Way. Using the spherical harmonic decomposition in a window excluding the Galactic plane, we show for 1 yr of Fermi data that adding a spherical template (such as a line-of-sight DM annihilation profile) to an astrophysical background significantly reduces χ 2 of the fit to the data. In some energy bins the significance of this DM fraction is above three sigma. This can be viewed as a hint of a DM annihilation signal, although astrophysical sources cannot be ruled out at this moment. We use the derived DM fraction as a conservative upper limit on the DM annihilation signal. In the case of bb annihilation channel the limits are about a factor of 2 less constraining than the limits from dwarf galaxies. The uncertainty of our method is dominated by systematics related to modeling the astrophysical background. We show that with 1 yr of Fermi data the statistical sensitivity would be sufficient to detect DM annihilation with thermal freeze-out cross section for masses below 100 GeV.
Theoretical analysis of dynamic chemical imaging with lasers using high-order harmonic generation
International Nuclear Information System (INIS)
Van-Hoang Le; Anh-Thu Le; Xie Ruihua; Lin, C. D.
2007-01-01
We report theoretical investigations of the tomographic procedure suggested by Itatani et al. [Nature (London) 432, 867 (2004)] for reconstructing highest occupied molecular orbitals (HOMOs) using high-order harmonic generation (HHG). Due to the limited range of harmonics from the plateau region, we found that even under the most favorable assumptions, it is still very difficult to obtain accurate HOMO wave functions using the tomographic procedure, but the symmetry of the HOMOs and the internuclear separation between the atoms can be accurately extracted, especially when lasers of longer wavelengths are used to generate the HHG. Since the tomographic procedure relies on approximating the continuum wave functions in the recombination process by plane waves, the method can no longer be applied upon the improvement of the theory. For future chemical imaging with lasers, we suggest that one may want to focus on how to extract the positions of atoms in molecules instead, by developing an iterative method such that the theoretically calculated macroscopic HHG spectra can best fit the experimental HHG data
Gonoskov, I A; Tsatrafyllis, N; Kominis, I K; Tzallas, P
2016-09-07
We analytically describe the strong-field light-electron interaction using a quantized coherent laser state with arbitrary photon number. We obtain a light-electron wave function which is a closed-form solution of the time-dependent Schrödinger equation (TDSE). This wave function provides information about the quantum optical features of the interaction not accessible by semi-classical theories. With this approach we can reveal the quantum optical properties of high harmonic generation (HHG) process in gases by measuring the photon statistics of the transmitted infrared (IR) laser radiation. This work can lead to novel experiments in high-resolution spectroscopy in extreme-ultraviolet (XUV) and attosecond science without the need to measure the XUV light, while it can pave the way for the development of intense non-classical light sources.
Cheng, Hang; Clymer, Jeffrey W; Ferko, Nicole C; Patel, Leena; Soleas, Ireena M; Cameron, Chris G; Hinoul, Piet
2016-01-01
Mastectomy and breast-conserving surgery (BCS) are important treatment options for breast cancer patients. A previous meta-analysis demonstrated that the risk of certain complications can be reduced with the Harmonic technology compared with conventional methods in mastectomy. However, the meta-analysis did not include studies of BCS patients and focused on a subset of surgical complications. The objective of this study was to compare Harmonic technology and conventional techniques for a range of clinical outcomes and complications in both mastectomy and BCS patients, including axillary lymph node dissection. A comprehensive literature search was performed for randomized controlled trials comparing Harmonic technology and conventional methods in breast cancer surgery. Outcome measures included blood loss, drainage volume, total complications, seroma, necrosis, wound infections, ecchymosis, hematoma, hospital length of stay, and operating time. Risk of bias was analyzed for all studies. Meta-analysis was performed using random-effects models for mean differences of continuous variables and a fixed-effects model for risk ratios of dichotomous variables. Twelve studies met the inclusion criteria. Across surgery types, compared to conventional techniques, Harmonic technology reduced total complications by 52% (P=0.002), seroma by 46% (Pmastectomy patients with lymph node dissection, Harmonic technology showed significant reductions in complications in the BCS study subgroup. In this meta-analysis of both mastectomy and BCS procedures, the use of Harmonic technology reduced the risk of most complications by about half across breast cancer surgery patients. These benefits may be due to superior hemostatic capabilities of Harmonic technology and better dissection, particularly lymph node dissection. Reduction in complications and other resource outcomes may engender lower downstream health care costs.
Second Harmonic Generation Imaging Analysis of Collagen Arrangement in Human Cornea.
Park, Choul Yong; Lee, Jimmy K; Chuck, Roy S
2015-08-01
To describe the horizontal arrangement of human corneal collagen bundles by using second harmonic generation (SHG) imaging. Human corneas were imaged with an inverted two photon excitation fluorescence microscope. The excitation laser (Ti:Sapphire) was tuned to 850 nm. Backscatter signals of SHG were collected through a 425/30-nm bandpass emission filter. Multiple, consecutive, and overlapping image stacks (z-stacks) were acquired to generate three dimensional data sets. ImageJ software was used to analyze the arrangement pattern (irregularity) of collagen bundles at each image plane. Collagen bundles in the corneal lamellae demonstrated a complex layout merging and splitting within a single lamellar plane. The patterns were significantly different in the superficial and limbal cornea when compared with deep and central regions. Collagen bundles were smaller in the superficial layer and larger in deep lamellae. By using SHG imaging, the horizontal arrangement of corneal collagen bundles was elucidated at different depths and focal regions of the human cornea.
Harmonic analysis, partial differential equations and applications in honor of Richard L. Wheeden
Franchi, Bruno; Lu, Guozhen; Perez, Carlos; Sawyer, Eric
2017-01-01
This is a collection of contributed papers by many eminent Harmonic Analysts and specialists of Partial Differential equations. The papers focus on weighted norm equalities for singular integrals, focusing wave equations, degenerate elliptic equations, Navier-Stokes flow in two dimensions and Poincare-Sobolev inequalities in the setting of metric spaces equipped with measures among others. Many topics considered in this volume stem from the interests of Richard L. Wheeden whose contributions to Potential Theory, singular integral theory and degenerate elliptic PDE theory this volume honors. Luis Caffarelli, Sagun Chanillo, Bruno Franchi, Cristian Guttierez, Xiaojun Huang, Carlos Kenig, Ermanno Lanconelli, Eric Sawyer and Alexander Volberg, are some of the many contributors to this volume. .
Potential for protein surface shape analysis using spherical harmonics and 3D Zernike descriptors.
Venkatraman, Vishwesh; Sael, Lee; Kihara, Daisuke
2009-01-01
With structure databases expanding at a rapid rate, the task at hand is to provide reliable clues to their molecular function and to be able to do so on a large scale. This, however, requires suitable encodings of the molecular structure which are amenable to fast screening. To this end, moment-based representations provide a compact and nonredundant description of molecular shape and other associated properties. In this article, we present an overview of some commonly used representations with specific focus on two schemes namely spherical harmonics and their extension, the 3D Zernike descriptors. Key features and differences of the two are reviewed and selected applications are highlighted. We further discuss recent advances covering aspects of shape and property-based comparison at both global and local levels and demonstrate their applicability through some of our studies.
Eck, Simon; Wörz, Stefan; Müller-Ott, Katharina; Hahn, Matthias; Biesdorf, Andreas; Schotta, Gunnar; Rippe, Karsten; Rohr, Karl
2016-08-01
The genome is partitioned into regions of euchromatin and heterochromatin. The organization of heterochromatin is important for the regulation of cellular processes such as chromosome segregation and gene silencing, and their misregulation is linked to cancer and other diseases. We present a model-based approach for automatic 3D segmentation and 3D shape analysis of heterochromatin foci from 3D confocal light microscopy images. Our approach employs a novel 3D intensity model based on spherical harmonics, which analytically describes the shape and intensities of the foci. The model parameters are determined by fitting the model to the image intensities using least-squares minimization. To characterize the 3D shape of the foci, we exploit the computed spherical harmonics coefficients and determine a shape descriptor. We applied our approach to 3D synthetic image data as well as real 3D static and real 3D time-lapse microscopy images, and compared the performance with that of previous approaches. It turned out that our approach yields accurate 3D segmentation results and performs better than previous approaches. We also show that our approach can be used for quantifying 3D shape differences of heterochromatin foci. Copyright © 2016 Elsevier B.V. All rights reserved.
Sorokin, Sergey V
2011-03-01
Helical springs serve as vibration isolators in virtually any suspension system. Various exact and approximate methods may be employed to determine the eigenfrequencies of vibrations of these structural elements and their dynamic transfer functions. The method of boundary integral equations is a meaningful alternative to obtain exact solutions of problems of the time-harmonic dynamics of elastic springs in the framework of Bernoulli-Euler beam theory. In this paper, the derivations of the Green's matrix, of the Somigliana's identities, and of the boundary integral equations are presented. The vibrational power transmission in an infinitely long spring is analyzed by means of the Green's matrix. The eigenfrequencies and the dynamic transfer functions are found by solving the boundary integral equations. In the course of analysis, the essential features and advantages of the method of boundary integral equations are highlighted. The reported analytical results may be used to study the time-harmonic motion in any wave guide governed by a system of linear differential equations in a single spatial coordinate along its axis. © 2011 Acoustical Society of America
Physics analysis tools for beauty physics in ATLAS
International Nuclear Information System (INIS)
Anastopoulos, C; Bouhova-Thacker, E; Catmore, J; Mora, L de; Dallison, S; Derue, F; Epp, B; Jussel, P; Kaczmarska, A; Radziewski, H v; Stahl, T; Reznicek, P
2008-01-01
The Large Hadron Collider experiments will search for physics phenomena beyond the Standard Model. Highly sensitive tests of beauty hadrons will represent an alternative approach to this research. The analysis of complex decay chains of the beauty hadrons have to efficiently extract the detector tracks made by these reactions and reject other events in order to make sufficiently precise measurement. This places severe demands on the software used to analyze the B-physics data. The ATLAS B-physics group has written a series of tools and algorithms for performing these tasks, to be run within the ATLAS offline software framework Athena. This paper describes this analysis suite, paying particular attention to mechanisms for handling combinatorics, interfaces to secondary vertex fitting packages, B-flavor tagging tools and finally Monte Carlo true information association to pursue simulation data in process of the software validations which is an important part of the development of the physics analysis tools
An Analysis of Canadian Physical Education Curricula
Kilborn, Michelle; Lorusso, Jenna; Francis, Nancy
2016-01-01
There has been much international concern about the present and future status of school physical education. Recent research has employed surveys or case studies to examine the status of physical education but there is a dearth of in-depth physical education curriculum document analysis. The aim of this study is to contribute to the international…
Directory of Open Access Journals (Sweden)
Ying Zhu
2018-06-01
Full Text Available This paper presents a novel third harmonic voltage differential stator grounding protection (THV-DSGP method combining the adaptive coefficient and fixed coefficient. It can solve the protection sensitivity degradation problem when the insulation resistance of stator winding to ground is slowly declining. This protection method retains the advantages of the adaptive coefficient, which is to maintain high sensitivity in case of an instantaneous ground fault. Moreover, the fixed coefficient can remember the initial insulation state of the stator winding and prevent relay failure when the stator insulation is slowly declining. In addition, due to zero-sequence voltage disconnection (ZSVD often leading to malfunctioning of the THV stator ground protection, the existing criterion of the ZSVD was improved according to the electrical characteristics of the generator when ZSVD happens. THV-DSGP with both adaptive coefficient and fixed coefficient was simulated in the Matlab/Simulink. The simulation results show that the proposed protection can be applied to the slow ground fault of the stator winding. Furthermore, the improved criterion of ZSVD can effectively distinguish the stator metal earth fault and the secondary loop break of the zero-sequence voltage.
Li, Xiaoli; Li, Duan; Voss, Logan J; Sleigh, Jamie W
2009-11-15
Brain functions are related to neuronal networks of different sizes and distribution, and neuronal networks of different sizes oscillate at different frequencies. Thus the synchronization of neuronal networks is often reflected by cross-frequency interaction. The description of this cross-frequency interaction is therefore a crucial issue in understanding the modulation mechanisms between neuronal populations. A number of different kinds of interaction between frequencies have been reported. In this paper, we develop a general harmonic wavelet transform based bicoherence using a phase randomization method. This allows us to measure the comodulation of oscillations between different frequency bands in neuronal populations. The performance of the method is evaluated by a simulation study. The results show that the improved wavelet bicoherence method can detect a reliable phase coupling value, and also identify zero bicoherence for waves that are not phase-coupled. Spurious bicoherences can be effectively eliminated through the phase randomization method. Finally, this method is applied to electrocorticogram data recorded from rats during transitions between slow-wave sleep, rapid-eye movement sleep and waking. The phase coupling in rapid-eye movement sleep is statistically lower than that during slow-wave sleep, and slightly less than those in the wakeful state. The degree of phase coupling in rapid-eye movement sleep after slow-wave sleep is greater than in rapid-eye movement sleep prior to waking. This method could be applied to investigate the cross-frequency interactions in other physiological signals.
Directory of Open Access Journals (Sweden)
Xinwei Wang
2016-11-01
Full Text Available Sandwich structures are widely used in practice and thus various engineering theories adopting simplifying assumptions are available. However, most engineering theories of beams, plates and shells cannot recover all stresses accurately through their constitutive equations. Therefore, the soft-core is directly modeled by two-dimensional (2D elasticity theory without any pre-assumption on the displacement field. The top and bottom faces act like the elastic supports on the top and bottom edges of the core. The differential equations of the 2D core are then solved by the harmonic differential quadrature method (HDQM. To circumvent the difficulties in dealing with the locally distributed load by point discrete methods such as the HDQM, a general and rigorous way is proposed to treat the locally distributed load. Detailed formulations are provided. The static behavior of sandwich panels under different locally distributed loads is investigated. For verification, results are compared with data obtained by ABAQUS with very fine meshes. A high degree of accuracy on both displacement and stress has been observed.
Bogdan, V. M.; Bond, V. B.
1980-01-01
The deviation of the solution of the differential equation y' = f(t, y), y(O) = y sub O from the solution of the perturbed system z' = f(t, z) + g(t, z), z(O) = z sub O was investigated for the case where f and g are continuous functions on I x R sup n into R sup n, where I = (o, a) or I = (o, infinity). These functions are assumed to satisfy the Lipschitz condition in the variable z. The space Lip(I) of all such functions with suitable norms forms a Banach space. By introducing a suitable norm in the space of continuous functions C(I), introducing the problem can be reduced to an equivalent problem in terminology of operators in such spaces. A theorem on existence and uniqueness of the solution is presented by means of Banach space technique. Norm estimates on the rate of growth of such solutions are found. As a consequence, estimates of deviation of a solution due to perturbation are obtained. Continuity of the solution on the initial data and on the perturbation is established. A nonlinear perturbation of the harmonic oscillator is considered a perturbation of equations of the restricted three body problem linearized at libration point.
International Nuclear Information System (INIS)
Green, M.I.; Barale, P.J.; Hassenzahl, W.V.; Nelson, D.H.; O'Neill, J.W.; Schafer, R.V.; Taylor, C.E.
1987-09-01
A cryogenic search-coil array has been fabricated at LBL for harmonic error analysis of SSC model quadrupoles. It consists of three triplets of coils; the center-coil triplet is 10 cm long, and the end coil triplets are 70 cm long. Design objectives are a high bucking ratio for the dipole and quadrupole signals and utility at cryogenic operating currents (∼6 kA) with sufficient sensitivity for use at room-temperature currents (∼10 A). the design and fabrication are described. Individual coils are mechanically measured to +-5 μm, and their magnetic areas measured to 0.05%. A computer program has been developed to predict the quadrupole and dipole bucking ratios from the mechanical and magnetic measurements. The calibration procedure and accuracy of the array are specified. Results of measurements of SSC model quadrupoles are presented. 1 ref., 4 figs
Directory of Open Access Journals (Sweden)
Pakos Wojciech
2015-09-01
Full Text Available The paper presents numerical analysis of harmonically excited vibration of a cable-stayed footbridge caused by a load function simulating crouching (squats while changing the static tension in chosen cables. The intentional synchronized motion (e.g., squats of a single person or group of persons on the footbridge with a frequency close to the natural frequency of the structure may lead to the resonant vibrations with large amplitudes. The appropriate tension changes in some cables cause detuning of resonance on account of stiffness changes of structures and hence detuning in the natural frequency that is close to the excitation frequency. The research was carried out on a 3D computer model of a real structure - a cable-stayed steel footbridge in Leśnica, a quarter of Wrocław, Poland, with the help of standard computer software based on FEM COSMOS/M System.
Pakos, Wojciech
2015-09-01
The paper presents numerical analysis of harmonically excited vibration of a cable-stayed footbridge caused by a load function simulating crouching (squats) while changing the static tension in chosen cables. The intentional synchronized motion (e.g., squats) of a single person or group of persons on the footbridge with a frequency close to the natural frequency of the structure may lead to the resonant vibrations with large amplitudes. The appropriate tension changes in some cables cause detuning of resonance on account of stiffness changes of structures and hence detuning in the natural frequency that is close to the excitation frequency. The research was carried out on a 3D computer model of a real structure - a cable-stayed steel footbridge in Leśnica, a quarter of Wrocław, Poland, with the help of standard computer software based on FEM COSMOS/M System.
International Nuclear Information System (INIS)
Yue Xiao-Le; Xu Wei; Zhang Ying; Wang Liang
2015-01-01
The piezomagnetoelastic energy harvester system subjected to harmonic and Poisson white noise excitations is studied by using the generalized cell mapping method. The transient and stationary probability density functions (PDFs) of response based on the global viewpoint are obtained by the matrix analysis method. Monte Carlo simulation results verify the accuracy of this method. It can be observed that evolutionary direction of transient and stationary PDFs is in accordance with the unstable manifold for this system, and a stochastic P-bifurcation occurs as the intensity of Poisson white noise increases. This study presents an efficient numerical tool to solve the stochastic response of a three-dimensional dynamical system and provides a new idea to analyze the energy harvester system. (paper)
Harmonic scalpel in multinodular goiter surgery: impact on surgery and cost analysis.
Sebag, Frederic; Fortanier, Cécile; Ippolito, Guiseppe; Lagier, Aude; Auquier, Pascal; Henry, Jean-Francois
2009-04-01
The aim of this study was to evaluate the potential advantages and the general operative cost of the Harmonic Scalpel (HS) in surgery for multinodular goiter (MNG). Patients undergoing total thyroidectomy (TT) for MNG were prospectively allocated in a conventional tie-and-clip (TC) group (n = 50) and an HS group (n = 50). All pre- and postoperative data were recorded. The economic evaluation was based on a microcost measurement and aimed to consider all the resources consumed for each patient during the surgical procedure. To compare the results, we used the nonparametric unpaired two-tailed Mann-Whitney test. There were 81 women and 19 men (mean age, 55 +/- 15 years). Mean preoperative TSH level was 1.2 (SD, 1.1) (TC) and 1.3 (SD, 2) (HS) (P = NS). Mean body mass index was 24.72 (SD, 8) (TC) and 25.6 (SD, 8) (HS) (P = NS). Four patients experienced a transient hypocalcemia (2 in each group). One patient had a postoperative hematoma requiring surgical evacuation (HS). One patient experienced a transient recurrent nerve palsy (TC). Mean length of surgery was 104 (SD, 32) (TC) and 84 minutes (SD, 17) (HS) (P = .0001). Mean length of hospitalization was 2 days in both groups (SD, 1) (P = NS). Mean operative cost per patient was 990 euro (SD, 191) in the TC group and 1,024 euro (SD, 143) in the HS group (P = NS). Safety and efficiency of the HS is comparable to the tie-and-clip technique in thyroid surgery. The use of the HS in MNG surgery allows for a significant reduction in the length of the procedure with a comparable cost.
Masoumi, S.; Safari, A.; Sharifi, M.; Sam Khaniani, A.
2011-12-01
In order to investigate regular variations of the ionosphere, the least-squares harmonic estimation is applied to the time series of ionospheric electron densities in the region of Iran derived from about five years of Global Positioning System Radio Occultation (GPS RO) observations by FORMOSAT-3/COSMIC satellites. Although the obtained results are slightly different from the expected ones due to the low horizontal resolution of RO measurements, high vertical resolution of the observations enables us to detect not only the Total Electron Content (TEC) variations, but also periodic patterns of electron densities in different altitudes of the ionosphere. Dominant diurnal and annual signals, together with their Fourier series decompositions, and also periods close to 27 days are obtained, which is consistent with the previous analyses on TEC. In the equatorial anomaly band, the annual component is weaker than its Fourier decomposition periods. In particular, the semiannual period dominates the annual component, which is probably due to the effect of geomagnetic field. By the investigation of the frequencies at different local times, the semiannual signal is more significant than the annual one in the daytime, while the annual frequency is dominant at night. By the detection of the phases of the components, it is revealed that the annual signal has its maximum in summer at high altitudes, and in winter at lower altitudes. This suggests the effect of neutral compositions in the lower atmosphere. Further, the semiannual component peaks around equinox during the day, while its maximum mostly occurs in solstice at night. Since RO measurements can be used to derive TEC along the signal path between a GPS satellite and a receiver, study on the potentiality of using these observations for the prediction of electron densities and its application to the ionospheric correction of the single frequency receivers is suggested.
Spatial Harmonic Decomposition as a tool for unsteady flow phenomena analysis
International Nuclear Information System (INIS)
Duparchy, A; Guillozet, J; De Colombel, T; Bornard, L
2014-01-01
Hydropower is already the largest single renewable electricity source today but its further development will face new deployment constraints such as large-scale projects in emerging economies and the growth of intermittent renewable energy technologies. The potential role of hydropower as a grid stabilizer leads to operating hydro power plants in ''off-design'' zones. As a result, new methods of analyzing associated unsteady phenomena are needed to improve the design of hydraulic turbines. The key idea of the development is to compute a spatial description of a phenomenon by using a combination from several sensor signals. The spatial harmonic decomposition (SHD) extends the concept of so-called synchronous and asynchronous pulsations by projecting sensor signals on a linearly independent set of a modal scheme. This mathematical approach is very generic as it can be applied on any linear distribution of a scalar quantity defined on a closed curve. After a mathematical description of SHD, this paper will discuss the impact of instrumentation and provide tools to understand SHD signals. Then, as an example of a practical application, SHD is applied on a model test measurement in order to capture and describe dynamic pressure fields. Particularly, the spatial description of the phenomena provides new tools to separate the part of pressure fluctuations that contribute to output power instability or mechanical stresses. The study of the machine stability in partial load operating range in turbine mode or the comparison between the gap pressure field and radial thrust behavior during turbine brake operation are both relevant illustrations of SHD contribution
Miles, Scott A; Rosen, David S; Grzywacz, Norberto M
2017-01-01
Studies have shown that some musical pieces may preferentially activate reward centers in the brain. Less is known, however, about the structural aspects of music that are associated with this activation. Based on the music cognition literature, we propose two hypotheses for why some musical pieces are preferred over others. The first, the Absolute-Surprise Hypothesis, states that unexpected events in music directly lead to pleasure. The second, the Contrastive-Surprise Hypothesis, proposes that the juxtaposition of unexpected events and subsequent expected events leads to an overall rewarding response. We tested these hypotheses within the framework of information theory, using the measure of "surprise." This information-theoretic variable mathematically describes how improbable an event is given a known distribution. We performed a statistical investigation of surprise in the harmonic structure of songs within a representative corpus of Western popular music, namely, the McGill Billboard Project corpus. We found that chords of songs in the top quartile of the Billboard chart showed greater average surprise than those in the bottom quartile. We also found that the different sections within top-quartile songs varied more in their average surprise than the sections within bottom-quartile songs. The results of this study are consistent with both the Absolute- and Contrastive-Surprise Hypotheses. Although these hypotheses seem contradictory to one another, we cannot yet discard the possibility that both absolute and contrastive types of surprise play roles in the enjoyment of popular music. We call this possibility the Hybrid-Surprise Hypothesis. The results of this statistical investigation have implications for both music cognition and the human neural mechanisms of esthetic judgments.
Formal analysis of physical theories
International Nuclear Information System (INIS)
Dalla Chiara, M.L.; Toraldo di Francia, G.
1979-01-01
The rules of inference that are made use of in formalization are considered. It is maintained that a physical law represents the universal assertion of a probability, and not the assessment of the probability of a universal assertion. The precision of the apparatus used to collect the experimental evidence is introduced as an essential part of the theoretical structure of physics. This approach allows the author to define the concept of truth in a satisfactory way, abandoning the unacceptable notion of approximate truth. It is shown that a considerable amount of light can be shed on a number of much debated problems arising in the logic of quantum mechanics. It is stressed that the deductive structure of quantum theory seems to be essentially founded on a kind of mixture of different logics. Two different concepts of truth are distinguished within quantum theory, an empirical truth and quantum-logical truth. (Auth.)
Arfken, George
1984-01-01
University Physics provides an authoritative treatment of physics. This book discusses the linear motion with constant acceleration; addition and subtraction of vectors; uniform circular motion and simple harmonic motion; and electrostatic energy of a charged capacitor. The behavior of materials in a non-uniform magnetic field; application of Kirchhoff's junction rule; Lorentz transformations; and Bernoulli's equation are also deliberated. This text likewise covers the speed of electromagnetic waves; origins of quantum physics; neutron activation analysis; and interference of light. This publi
The Harmonization of Accounting
Directory of Open Access Journals (Sweden)
Hajnal Noémi
2017-11-01
Full Text Available The development and configuration of the regulatory framework of the accounting systems in Romania and Hungary took place in different ways. Among the reasons for the diversities in these countries’ accounting systems, the following can be certainly mentioned: different purposes of taxation, legal structure, the accountancy’s connection with the corporate law and family law, diversification on corporate financing policy, and cultural heterogeneity. Both countries quickly caught up with the international accounting harmonization standards. The adaptation of the international accounting standards has many advantages and disadvantages; these have been discussed in several previous researches. This paper aims at comparing the Romanian and Hungarian states’ accounting regulations from the early 1990s, which were implemented in order to harmonize the states’ accountancy regulations with the international standards, and their impact on the economy, based on secondary analysis.
Vesapogu, Joshi Manohar; Peddakotla, Sujatha; Kuppa, Seetha Rama Anjaneyulu
2013-01-01
With the advancements in semiconductor technology, high power medium voltage (MV) Drives are extensively used in numerous industrial applications. Challenging technical requirements of MV Drives is to control multilevel inverter (MLI) with less Total harmonic distortion (%THD) which satisfies IEEE standard 519-1992 harmonic guidelines and less switching losses. Among all modulation control strategies for MLI, Selective harmonic elimination (SHE) technique is one of the traditionally preferred modulation control technique at fundamental switching frequency with better harmonic profile. On the other hand, the equations which are formed by SHE technique are highly non-linear in nature, may exist multiple, single or even no solution at particular modulation index (MI). However, in some MV Drive applications, it is required to operate over a range of MI. Providing analytical solutions for SHE equations during the whole range of MI from 0 to 1, has been a challenging task for researchers. In this paper, an attempt is made to solve SHE equations by using deterministic and stochastic optimization methods and comparative harmonic analysis has been carried out. An effective algorithm which minimizes %THD with less computational effort among all optimization algorithms has been presented. To validate the effectiveness of proposed MPSO technique, an experiment is carried out on a low power proto type of three phase CHB 11- level Inverter using FPGA based Xilinx's Spartan -3A DSP Controller. The experimental results proved that MPSO technique has successfully solved SHE equations over all range of MI from 0 to 1, the %THD obtained over major range of MI also satisfies IEEE 519-1992 harmonic guidelines too.
Trends in physics data analysis algorithms
International Nuclear Information System (INIS)
Denby, B.
2004-01-01
The paper provides a new look at algorithmic trends in modern physics experiments. Based on recently presented material, it attempts to draw conclusions in order to form a coherent historical picture of the past, present, and possible future of the field of data analysis techniques in physics. The importance of cross disciplinary approaches is stressed
Advanced analysis methods in particle physics
Energy Technology Data Exchange (ETDEWEB)
Bhat, Pushpalatha C.; /Fermilab
2010-10-01
Each generation of high energy physics experiments is grander in scale than the previous - more powerful, more complex and more demanding in terms of data handling and analysis. The spectacular performance of the Tevatron and the beginning of operations of the Large Hadron Collider, have placed us at the threshold of a new era in particle physics. The discovery of the Higgs boson or another agent of electroweak symmetry breaking and evidence of new physics may be just around the corner. The greatest challenge in these pursuits is to extract the extremely rare signals, if any, from huge backgrounds arising from known physics processes. The use of advanced analysis techniques is crucial in achieving this goal. In this review, I discuss the concepts of optimal analysis, some important advanced analysis methods and a few examples. The judicious use of these advanced methods should enable new discoveries and produce results with better precision, robustness and clarity.
Directory of Open Access Journals (Sweden)
Cheng H
2016-07-01
Full Text Available Hang Cheng,1 Jeffrey W Clymer,1 Nicole C Ferko,2 Leena Patel,2 Ireena M Soleas,2 Chris G Cameron,2 Piet Hinoul1 1Ethicon Inc., Cincinnati, OH, USA; 2Cornerstone Research Group, Burlington, ON, Canada Background: Mastectomy and breast-conserving surgery (BCS are important treatment options for breast cancer patients. A previous meta-analysis demonstrated that the risk of certain complications can be reduced with the Harmonic technology compared with conventional methods in mastectomy. However, the meta-analysis did not include studies of BCS patients and focused on a subset of surgical complications. The objective of this study was to compare Harmonic technology and conventional techniques for a range of clinical outcomes and complications in both mastectomy and BCS patients, including axillary lymph node dissection.Methods: A comprehensive literature search was performed for randomized controlled trials comparing Harmonic technology and conventional methods in breast cancer surgery. Outcome measures included blood loss, drainage volume, total complications, seroma, necrosis, wound infections, ecchymosis, hematoma, hospital length of stay, and operating time. Risk of bias was analyzed for all studies. Meta-analysis was performed using random-effects models for mean differences of continuous variables and a fixed-effects model for risk ratios of dichotomous variables.Results: Twelve studies met the inclusion criteria. Across surgery types, compared to conventional techniques, Harmonic technology reduced total complications by 52% (P=0.002, seroma by 46% (P<0.0001, necrosis by 49% (P=0.04, postoperative chest wall drainage by 46% (P=0.0005, blood loss by 38% (P=0.0005, and length of stay by 22% (P=0.007. Although benefits generally appeared greatest in mastectomy patients with lymph node dissection, Harmonic technology showed significant reductions in complications in the BCS study subgroup.Conclusion: In this meta-analysis of both mastectomy and
Gesture analysis for physics education researchers
Directory of Open Access Journals (Sweden)
Rachel E. Scherr
2008-01-01
Full Text Available Systematic observations of student gestures can not only fill in gaps in students’ verbal expressions, but can also offer valuable information about student ideas, including their source, their novelty to the speaker, and their construction in real time. This paper provides a review of the research in gesture analysis that is most relevant to physics education researchers and illustrates gesture analysis for the purpose of better understanding student thinking about physics.
Directory of Open Access Journals (Sweden)
Piotr FOLĘGA
2014-03-01
Full Text Available The variety of types and sizes currently in production harmonic drive is a problem in their rational choice. Properly selected harmonic drive must meet certain requirements during operation, and achieve the anticipated service life. The paper discusses the problems associated with the selection of the harmonic drive. It also presents the algorithm correct choice of harmonic drive. The main objective of this study was to develop a computer program that allows the correct choice of harmonic drive by developed algorithm.
Tripathy, Manoj
2012-01-01
This paper describes a new approach for power transformer differential protection which is based on the wave-shape recognition technique. An algorithm based on neural network principal component analysis (NNPCA) with back-propagation learning is proposed for digital differential protection of power transformer. The principal component analysis is used to preprocess the data from power system in order to eliminate redundant information and enhance hidden pattern of differential current to disc...
Advanced Analysis Methods in High Energy Physics
Energy Technology Data Exchange (ETDEWEB)
Pushpalatha C. Bhat
2001-10-03
During the coming decade, high energy physics experiments at the Fermilab Tevatron and around the globe will use very sophisticated equipment to record unprecedented amounts of data in the hope of making major discoveries that may unravel some of Nature's deepest mysteries. The discovery of the Higgs boson and signals of new physics may be around the corner. The use of advanced analysis techniques will be crucial in achieving these goals. The author discusses some of the novel methods of analysis that could prove to be particularly valuable for finding evidence of any new physics, for improving precision measurements and for exploring parameter spaces of theoretical models.
Directory of Open Access Journals (Sweden)
Yang Wen-Huan
2014-11-01
Full Text Available Aiming at the problem that the distribution network voltage will fluctuate because of the inter-harmonic currents injected into the network by double PWM speed control system when regulating the speed of the asynchronous motor, we established the inter-harmonic current math model of double PWM speed control system according to switching function based on a real bridge crane. The distribution law of the inter-harmonic is got by calculating the grid-side currents and their spectrum while letting the motor run at different quadrants and frequencies. The result which is verified by simulation and experiment shows that the content of the inter harmonic currents is more than that of harmonic currents in double PWM speed control system, the frequency of the inter harmonics of the grid-side current mainly focus on the scope lower than the fundamental frequency, and when the motor runs at low frequencies, the THD of the grid-side current is high. The result has verified the reason why the voltage of a bridge crane distribution system of a deepwater port in Shanghai flickers.
Clash of Harmonics in Stravinsky's "The Rite of Spring"
Ruiz, Michael J.
2018-01-01
This paper describes a fascinating connection between the physics of music and the famous chord in the dissonant rhythmic section of Stravinsky's "The Rite of Spring" (1913). The analysis of Stravinsky's chord will draw from the physics of harmonics, musical intervals, mathematics, and cognitive psychology. This highly interdisciplinary…
The Application of Vector Fitting to Eigenvalue-based Harmonic Stability Analysis
DEFF Research Database (Denmark)
Dowlatabadi, Mohammadkazem Bakhshizadeh; Yoon, Changwoo; Hjerrild, Jesper
2017-01-01
Participation factor analysis is an interesting feature of the eigenvalue-based stability analysis in a power system, which enables the developers to identify the problematic elements in a multi-vendor project like in an offshore wind power plant. However, this method needs a full state space model...... of the elements that is not always possible to have in a competitive world due to confidentiality. In this paper, by using an identification method, the state space models for power converters are extracted from the provided data by the suppliers. Some uncertainties in the identification process are also...
Harmonic analysis of dense time series of landsat imagery for modeling change in forest conditions
Barry Tyler. Wilson
2015-01-01
This study examined the utility of dense time series of Landsat imagery for small area estimation and mapping of change in forest conditions over time. The study area was a region in north central Wisconsin for which Landsat 7 ETM+ imagery and field measurements from the Forest Inventory and Analysis program are available for the decade of 2003 to 2012. For the periods...
Spectral harmonic analysis and synthesis of Earth’s crust gravity field
Tenzer, R.; Novák, P.; Vajda, P.; Gladkikh, V.; Hamayun, K.
2011-01-01
We developed and applied a novel numerical scheme for a gravimetric forward modelling of the Earth’s crustal density structures based entirely on methods for a spherical analysis and synthesis of the gravitational field. This numerical scheme utilises expressions for the gravitational potentials and
Global analysis of crisis in twin-well Duffing system under harmonic excitation in presence of noise
International Nuclear Information System (INIS)
Xu Wei; He Qun; Fang Tong; Rong Haiwu
2005-01-01
Evolution of a crisis in a twin-well Duffing system under a harmonic excitation in presence of noise is explored in detail by the generalized cell mapping with digraph (GCMD in short) method. System parameters are chosen in the range that there co-exist chaotic attractors and/or chaotic saddles, together with their evolution. Due to noise effects, chaotic attractors and chaotic saddles here are all noisy (random or stochastic) ones, so is the crisis. Thus, noisy crisis happens whenever a noisy chaotic attractor collides with a noisy saddle, whether the latter is chaotic or not. A crisis, which results in sudden appear (or dismissal) of a chaotic attractor, together with its attractive basin, is called a catastrophic one. In addition, a crisis, which just results in sudden change of the size of a chaotic attractor and its attractive basin, is called an explosive one. Our study reveals that noisy catastrophic crisis and noisy explosive crisis often occur alternatively during the evolutionary long run of noisy crisis. Our study also reveals that the generalized cell mapping with digraph method is a powerful tool for global analysis of crisis, capable of providing clear and vivid scenarios of the mechanism of development, occurrence, and evolution of a noisy crisis
Investigating student understanding of simple harmonic motion
Somroob, S.; Wattanakasiwich, P.
2017-09-01
This study aimed to investigate students’ understanding and develop instructional material on a topic of simple harmonic motion. Participants were 60 students taking a course on vibrations and wave and 46 students taking a course on Physics 2 and 28 students taking a course on Fundamental Physics 2 on the 2nd semester of an academic year 2016. A 16-question conceptual test and tutorial activities had been developed from previous research findings and evaluated by three physics experts in teaching mechanics before using in a real classroom. Data collection included both qualitative and quantitative methods. Item analysis and whole-test analysis were determined from student responses in the conceptual test. As results, most students had misconceptions about restoring force and they had problems connecting mathematical solutions to real motions, especially phase angle. Moreover, they had problems with interpreting mechanical energy from graphs and diagrams of the motion. These results were used to develop effective instructional materials to enhance student abilities in understanding simple harmonic motion in term of multiple representations.
International Nuclear Information System (INIS)
Carassiti, F.; Cigna, R.; Goolamallee, R.; Gusmano, G.
1989-01-01
The analysis of the electrochemical noise, i.e. of the spontaneous fluctuations of potential of a freely corroding electrode, probably represent one of the most interesting novelty of the last years in the field of corrosion monitoring. Although this technique is still at an early stage, it could lead to interesting developments, especially for identifying localized forms of corrosion. The experiments which have been reported in the literature generally agree that in absence of active corrosion a slight variation of the potential is observed accompanied by non gaussian fluctuations; in presence of the onset of pitting a series of sharp variation is observed followed by relatively slow exponential recovery. In the domain of frequency the slope of the noise frequency curve is less than that noticed in the absence of active corrosion. In the domain of time generally the standard deviation of noise is proportional to the corrosion rate. Moreover it has been noticed that small variation in the experimental condition could cause modification in the shape of the spontaneous potential fluctuation and introduce some confusion in the analysis of data. Digital filtering of disturbs could allow a better reproducibility to be achieved. (author) 4 refs., 9 figs
Nonlinear processes in laser-produced dense plasma (observation of the fractional harmonics)
International Nuclear Information System (INIS)
Lyu, K.S.
1988-01-01
One of the main issues of laser plasma physics interactions is harmonic generation. The harmonic emission spectrum provides clues as to which non-linear processes take place in the plasma. Several effects contribute to a given line as judged from the complexity of the actual spectra. Unfolding of them has not been done satisfactorily yet. Harmonic lines with half integer or integer orders have been observed, but the physics are far from complete. In this dissertation research, we observed the usual second harmonic generation and a set of fractional harmonics which we believe have been observed for the first time in plasma physics. The plasma was produced by a high power laser and we have characterized its properties from the analysis of the radiation spectra, including the harmonic lines, as measured using the methods of transient spectroscopy. We produced the plasma with a Nd:glass laser which had a 65 nsec pulse width (FWHM) with a total energy of up to 6 Joules. The targets were steel alloys, copper, and aluminum. The harmonic generation from the plasma with a planar metal target was not strong. But, it became stronger when we made a dead hole (cavity) at the laser spot on the target surface. The second harmonic line appears first before the time of the peak of laser pulse. The fractional harmonics, which are related to the laser wavelength by rational number other than integers or half integers, appear near or after the time of the laser peak and weaker in UV wavelength range but stronger if some atomic emission line are near by. To understand the plasma evolution better, we developed computer simulation codes. The codes contain all relevant processes necessary to compute the plasma evolution
Chemical Applications of Second Harmonic Rayleigh Scattering ...
Indian Academy of Sciences (India)
Chemical Applications of Second Harmonic Rayleigh Scattering Puspendu Kumar Das Department of Inorganic and Physical Chemistry Indian Institute of Science Bangalore 560012, India pkdas@ipc.iisc.ernet.in.
Directory of Open Access Journals (Sweden)
Joanna Kurowska-Pysz
2017-12-01
Full Text Available Cross-border partnerships are a distinctive example of inter-organizational cooperation, embedded, in terms of territory, in the neighboring borderland regions of two or more countries. The aim of this paper is to identify factors that contribute to the sustainable cross-border cooperation and affect motivation to increase cooperation between cross-border partners. The objective implementation is connected with the verification of a hypothesis referring to the possible impact of the European Union funds on the trans-boundary cooperation transformations. Results of desk research and quantitative research involving IDI, CATI, CAWI and CATI and PAPI data collection methods, implemented in the Polish–Czech borderland in 2016 were used in this paper. Research on the Polish–Lithuanian borderland was also used in the paper to conduct comparative analysis, useful to identify and evaluate factors motivating sustainable cross-border cooperation in the Czech–Polish borderland. The sustainable, cross-border and inter-organizational cooperation in the borderlands results from the simultaneous interaction of three groups of factors: (1 people and institutions (the quality of interpersonal relationships; (2 cross-border planning, procedures and support mechanisms (e.g., the possibility of jointly planning the cross-border cooperation and obtaining EU funds for the development of the borderlands as well as the availability of other funds helpful in this kind of cooperation; and (3 environment (historical affinity and geographical proximity of neighboring border regions, system support at the regional and local level in neighboring countries.
Directory of Open Access Journals (Sweden)
T.E. Danova
2016-06-01
Full Text Available The results of the investigations of a transformed series of reconstructed air temperature data for the central part of Greenland with an increment of 30 years have been presented. Stationarization of a ~ 50,000-years’ series of the reconstructed air temperature in the central part of Greenland according to ice core data has been performed using mathematical expectation. To obtain mathematical expectation estimation, the smoothing procedure by the methods of moving average and wavelet analysis has been carried out. Fourier’s transformation has been applied repeatedly to the stationarized series with changing the averaging time in the process of smoothing. Three averaging time values have been selected for the investigations: ~ 400–500 years, ~ 2,000 years, and ~ 4,000 years. Stationarization of the reconstructed temperature series with the help of wavelet transformation showed the best results when applying the averaging time of ~ 400 and ~ 2000 years, the trends well characterize the initial temperature series, there-by revealing the main patterns of its dynamics. Using the period with the averaging time of ~ 4,000 years showed the worst result: significant events of the main temperature series were lost in the process of averaging. The obtained results well correspond to cycling known to be inherent to the climatic system of the planet; the detected modes of 1,470 ± 500 years are comparable to the Dansgaard–Oeschger and Bond oscillations.
Harmonic Function of Poincare Cone Condition In Solving Dirichlet ...
African Journals Online (AJOL)
Harmonic Function of Poincare Cone Condition In Solving Dirichlet Problem. ... Journal of the Nigerian Association of Mathematical Physics ... theorem, the dirichlet problem and maximum principle where we conclude that the application of sums , differences and scalar multiples of harmonic functions are again harmonic.
Next generation data harmonization
Armstrong, Chandler; Brown, Ryan M.; Chaves, Jillian; Czerniejewski, Adam; Del Vecchio, Justin; Perkins, Timothy K.; Rudnicki, Ron; Tauer, Greg
2015-05-01
Analysts are presented with a never ending stream of data sources. Often, subsets of data sources to solve problems are easily identified but the process to align data sets is time consuming. However, many semantic technologies do allow for fast harmonization of data to overcome these problems. These include ontologies that serve as alignment targets, visual tools and natural language processing that generate semantic graphs in terms of the ontologies, and analytics that leverage these graphs. This research reviews a developed prototype that employs all these approaches to perform analysis across disparate data sources documenting violent, extremist events.
Clymer, Jeffrey; Cheng,Hang; Ferko,Nicole; Patel,Leena; Soleas,Ireena M; Cameron,Chris G; Hinoul,Piet
2016-01-01
Hang Cheng,1 Jeffrey W Clymer,1 Nicole C Ferko,2 Leena Patel,2 Ireena M Soleas,2 Chris G Cameron,2 Piet Hinoul1 1Ethicon Inc., Cincinnati, OH, USA; 2Cornerstone Research Group, Burlington, ON, Canada Background: Mastectomy and breast-conserving surgery (BCS) are important treatment options for breast cancer patients. A previous meta-analysis demonstrated that the risk of certain complications can be reduced with the Harmonic technology compared with conventional methods in mastectomy. However...
Sánchez-Úbeda, Juan Pedro; Calvache, María Luisa; Duque, Carlos; López-Chicano, Manuel
2016-11-01
A new methodology has been developed to obtain tidal-filtered time series of groundwater levels in coastal aquifers. Two methods used for oceanography processing and forecasting of sea level data were adapted for this purpose and compared: HA (Harmonic Analysis) and CWT (Continuous Wavelet Transform). The filtering process is generally comprised of two main steps: the detection and fitting of the major tide constituents through the decomposition of the original signal and the subsequent extraction of the complete tidal oscillations. The abilities of the optional HA and CWT methods to decompose and extract the tidal oscillations were assessed by applying them to the data from two piezometers at different depths close to the shoreline of a Mediterranean coastal aquifer (Motril-Salobreña, SE Spain). These methods were applied to three time series of different lengths (one month, one year, and 3.7 years of hourly data) to determine the range of detected frequencies. The different lengths of time series were also used to determine the fit accuracies of the tidal constituents for both the sea level and groundwater heads measurements. The detected tidal constituents were better resolved with increasing depth in the aquifer. The application of these methods yielded a detailed resolution of the tidal components, which enabled the extraction of the major tidal constituents of the sea level measurements from the groundwater heads (e.g., semi-diurnal, diurnal, fortnightly, monthly, semi-annual and annual). In the two wells studied, the CWT method was shown to be a more effective method than HA for extracting the tidal constituents of highest and lowest frequencies from groundwater head measurements.
Sanchez, Braulio V.; Nishihama, Masahiro
1997-01-01
Half-daily global wind speeds in the east-west (u) and north-south (v) directions at the 10-meter height level were obtained from the European Centre for Medium Range Weather Forecasts (ECMWF) data set of global analyses. The data set covered the period 1985 January to 1995 January. A spherical harmonic expansion to degree and order 50 was used to perform harmonic analysis of the east-west (u) and north-south (v) velocity field components. The resulting wind field is displayed, as well as the residual of the fit, at a particular time. The contribution of particular coefficients is shown. The time variability of the coefficients up to degree and order 3 is presented. Corresponding power spectrum plots are given. Time series analyses were applied also to the power associated with degrees 0-10; the results are included.
Extended standard vector analysis for plasma physics
International Nuclear Information System (INIS)
Wimmel, H.K.
1982-02-01
Standard vector analysis in 3-dimensional space, as found in most tables and textbooks, is complemented by a number of basic formulas that seem to be largely unknown, but are important in themselves and for some plasma physics applications, as is shown by several examples. (orig.)
Automatic Functional Harmonic Analysis
de Haas, W.B.; Magalhães, J.P.; Wiering, F.; Veltkamp, R.C.
2013-01-01
Music scholars have been studying tonal harmony intensively for centuries, yielding numerous theories and models. Unfortunately, a large number of these theories are formulated in a rather informal fashion and lack mathematical precision. In this article we present HarmTrace, a functional model of
Clash of Harmonics in Stravinsky's The Rite of Spring
Ruiz, Michael J.
2018-04-01
This paper describes a fascinating connection between the physics of music and the famous chord in the dissonant rhythmic section of Stravinsky's The Rite of Spring (1913). The analysis of Stravinsky's chord will draw from the physics of harmonics, musical intervals, mathematics, and cognitive psychology. This highly interdisciplinary approach will especially appeal to students typically found in a physics course for non-majors. A video accompanies this paper so that readers and students can hear the construction of Stravinsky's dissonant chord as well as an orchestra performing an excerpt of The Rite of Spring.
Lanci, Luca; Kissel, Catherine; Leonhardt, Roman; Laj, Carlo
2008-08-01
Based on 5 published marine high-resolution sedimentary records of the Iceland Basin Excursion [IBE; Channell, J.E.T., Hodell, D.A., Lehman, B., 1997. Relative geomagnetic paleointensity and ∂ 18O at ODP Site 983/Gardar Drift, North Atlantic since 350 ka. Earth Planet. Sci. Lett. 153, 103-118; Laj, C., Kissel, C., Roberts, A., 2006. Geomagnetic field behavior during the Iceland Basin and Laschamp geomagnetic excursions: a simple transitional field geometry? Geochem. Geophys. Geosystems. 7, Q03004, doi:10.1029/2005GC001122] dated around 186-190 kyr, we present models of the excursional geomagnetic field at the Earth's surface using two different approaches. First a spherical harmonics analysis is performed after synchronization of the records using their paleointensity profiles. Second, we have used an iterative Bayesian inversion procedure, calibrated using the single volcanic data available so far. Both modeling approaches suffer from imperfections of the paleomagnetic signals and mostly from the still poor geographical distribution of detailed records, presently available only from the North Atlantic and the West Pacific. For these reasons, our modeling results should only be regarded as preliminary models of the geomagnetic field during the IBE, susceptible to improvements when including results from future paleomagnetic studies. Nevertheless, both approaches show distinct similarities and are stable against moderate variations of modeling parameters. The general picture is that of a dipole field undergoing a strong reduction, but remaining higher than the non-dipole field all through the excursional process, except for a very short interval of time corresponding to the dipole minimum at the center of the excursion. On the other hand, some differences exist between the results of the two models with each other and with the real data when the virtual geomagnetic pole (VGP) paths are considered. The non-dipole field does not appear to undergo very significant
Introduction to Classical and Quantum Harmonic Oscillators
International Nuclear Information System (INIS)
Latal, H
1997-01-01
As the title aptly states, this book deals with harmonic oscillators of various kinds, from classical mechanical and electrical oscillations up to quantum oscillations. It is written in a lively language, and occasional interspersed anecdotes make the reading of an otherwise mathematically oriented text quite a pleasure. Although the author claims to have written an 'elementary introduction', it is certainly necessary to have a good deal of previous knowledge in physics (mechanics, electrodynamics, quantum theory), electrical engineering and, of course, mathematics in order to follow the general line of his arguments. The book begins with a thorough treatment of classical oscillators (free, damped, forced) that is followed by an elaboration on Fourier analysis. Lagrange and Hamilton formalisms are then introduced before the problem of coupled oscillations is attacked. A chapter on statistical perspectives leads over to the final discussion of quantum oscillations. With the book comes a diskette containing a number of worksheets (Microsoft Excel) that can be used by the reader for instant visualization to get a better qualitative and quantitative understanding of the material. To the reviewer it seems difficult to pinpoint exactly the range of prospective readership of the book. It can certainly not be intended as a textbook for students, but rather as a reference book for teachers of physics or researchers, who want to look up one or other aspect of harmonic oscillations, for which purpose the diskette represents a very valuable tool. (book review)
Directory of Open Access Journals (Sweden)
H. R. Liu
2015-01-01
Full Text Available Considering a sort of elastic mass with asymmetric hysteresis characteristic which widespread existing in engineering field, a piecewise-nonlinear dynamical equation, which contains asymmetric hysteretic loop, is established. By using the method of Incremental Harmonic Balance (IHB, the analytic linearized algebraic equation of the system is obtained. On the basis of this algebraic equation, the coefficients of the algebraic expression are figured out by the incremental procedure and the iterative process of the regulated variable. Through the emulation, the amplitude frequency response curve and the relation between the value of the harmonic component and the external excitation are researched; the bistable regions of the bifurcation diagram of the system under the variation of the excitation amplitude are studied. The above results can be used to guide the research of the asymmetric hysteretic system with polynomial expression.
Directory of Open Access Journals (Sweden)
Aslan İNAN
2005-01-01
Full Text Available The losses in the power systems should be low as possible as. Saving energy instead of loses (kWh in power utilities can supply much more energy to the consumers. The lower losses the more energy is saved and thus the power system becomes more economical. In recent years, the increasing number of applications and power ratings of the devices which have nonlinear voltage-current characteristics cause voltage waveform distortion and additional losses. While evaluating losses considering harmonics will provide more contribution to obtain more accurate results. In this study, Artificial Neural Networks (ANN method has been presented to predict the harmonic losses in unbalanced power systems by using the data from balanced power system with nonlinear loads.
Fischer, P.; Jardani, A.; Cardiff, M.; Lecoq, N.; Jourde, H.
2018-04-01
In a karstic field, the flow paths are very complex as they globally follow the conduit network. The responses generated from an investigation in this type of aquifer can be spatially highly variable. Therefore, the aim of the investigation in this case is to define a degree of connectivity between points of the field, in order to understand these flow paths. Harmonic pumping tests represent a possible investigation method for characterizing the subsurface flow of groundwater. They have several advantages compared to a constant-rate pumping (more signal possibilities, ease of extracting the signal in the responses and possibility of closed loop investigation). We show in this work that interpreting the responses from a harmonic pumping test is very useful for delineating a degree of connectivity between measurement points. We have firstly studied the amplitude and phase offset of responses from a harmonic pumping test in a theoretical synthetic modeling case in order to define a qualitative interpretation method in the time and frequency domains. Three different type of responses have been separated: a conduit connectivity response, a matrix connectivity, and a dual connectivity (response of a point in the matrix, but close to a conduit). We have then applied this method to measured responses at a field research site. Our interpretation method permits a quick and easy reconstruction of the main flow paths, and the whole set of field responses appear to give a similar range of responses to those seen in the theoretical synthetic case.
Analysis and projections of physics in Chile
International Nuclear Information System (INIS)
Soto, Leopoldo; Zambra, Marcelo; Loewe, Marcelo; Gutierrez, Gonzalo; Molina, Mario; Barra, Felipe; Lund, Fernando; Saavedra, Carlos; Haberle, Patricio
2008-01-01
In the present work, an assessment of the Physics research capacity in Chile is presented. For this, the period between 2000 and June 2005 has been studied. In this period almost 200 physicists have contributed to scientific production in terms of ISI publications. Amongst these 200, ∼160 correspond to theoretical physicists and only ∼40 to experimental physicists; ∼178 are men and only ∼22 are women. A more detailed analysis shows that ∼160 physicists have at least one appearance in ISI publications per year considering the last 3 years. Ten years ago, a similar criteria (at least one appearance per year in ISI articles, considering mobile three-year periods), the number of active physicists in the Chilean community was estimated at 70. Therefore, the Chilean active physicists' community has doubled in 10 years. There exist 20 centres in which scientific research is developed: 18 university centres, a government institute and a private institute. As regards scientific productivity, both as related to disciplines or research areas, and well as in relation to research centres, it is found that, generally, scientific production, in a particular area in Physics or in a research centre, is directly related to the number of corresponding researchers; that is to say, the percentage of the national productivity in an area or research centre corresponds to its share in the total number of physicists in the country. A geographical analysis shows that 50% of the productivity corresponds to Santiago and 50% to the rest of the country. The impact of the different funds for research is assessed, also: FONDECYT, Presidential Chairs and large projects and centres of excellence. According to Physics researchers opinion, Fondo Nacional de Ciencia y TecnologIa (FONDECYT, National Fund fro Science and Technology) has become the best instrument to support researchi activities in Chile. However, the amount of projects awarded has practically not been increased, which is
Analysis and projections of physics in Chile
Soto, Leopoldo; Zambra, Marcelo; Loewe, Marcelo; Gutiérrez, Gonzalo; Molina, Mario; Barra, Felipe; Lund, Fernando; Saavedra, Carlos; Haberle, Patricio
2008-11-01
In the present work, an assessment of the Physics research capacity in Chile is presented. For this, the period between 2000 and June 2005 has been studied. In this period almost 200 physicists have contributed to scientific production in terms of ISI publications. Amongst these 200, ~160 correspond to theoretical physicists and only ~40 to experimental physicists; ~178 are men and only ~22 are women. A more detailed analysis shows that ~160 physicists have at least one appearance in ISI publications per year considering the last 3 years. Ten years ago, a similar criteria (at least one appearance per year in ISI articles, considering mobile three-year periods), the number of active physicists in the Chilean community was estimated at 70. Therefore, the Chilean active physicists' community has doubled in 10 years. There exist 20 centres in which scientific research is developed: 18 university centres, a government institute and a private institute. As regards scientific productivity, both as related to disciplines or research areas, and well as in relation to research centres, it is found that, generally, scientific production, in a particular area in Physics or in a research centre, is directly related to the number of corresponding researchers; that is to say, the percentage of the national productivity in an area or research centre corresponds to its share in the total number of physicists in the country. A geographical analysis shows that 50% of the productivity corresponds to Santiago and 50% to the rest of the country. The impact of the different funds for research is assessed, also: FONDECYT, Presidential Chairs and large projects and centres of excellence. According to Physics researchers opinion, Fondo Nacional de Ciencia y Tecnología (FONDECYT, National Fund fro Science and Technology) has become the best instrument to support researchi activities in Chile. However, the amount of projects awarded has practically not been increased, which is insufficient
Visual physics analysis-from desktop to physics analysis at your fingertips
International Nuclear Information System (INIS)
Bretz, H-P; Erdmann, M; Fischer, R; Hinzmann, A; Klingebiel, D; Komm, M; Lingemann, J; Rieger, M; Müller, G; Steggemann, J; Winchen, T
2012-01-01
Visual Physics Analysis (VISPA) is an analysis environment with applications in high energy and astroparticle physics. Based on a data-flow-driven paradigm, it allows users to combine graphical steering with self-written C++ and Python modules. This contribution presents new concepts integrated in VISPA: layers, convenient analysis execution, and web-based physics analysis. While the convenient execution offers full flexibility to vary settings for the execution phase of an analysis, layers allow to create different views of the analysis already during its design phase. Thus, one application of layers is to define different stages of an analysis (e.g. event selection and statistical analysis). However, there are other use cases such as to independently optimize settings for different types of input data in order to guide all data through the same analysis flow. The new execution feature makes job submission to local clusters as well as the LHC Computing Grid possible directly from VISPA. Web-based physics analysis is realized in the VISPA-Web project, which represents a whole new way to design and execute analyses via a standard web browser.
Gender and Physics: a Theoretical Analysis
Rolin, Kristina
This article argues that the objections raised by Koertge (1998), Gross and Levitt (1994), and Weinberg (1996) against feminist scholarship on gender and physics are unwarranted. The objections are that feminist science studies perpetuate gender stereotypes, are irrelevant to the content of physics, or promote epistemic relativism. In the first part of this article I argue that the concept of gender, as it has been developed in feminist theory, is a key to understanding why the first objection is misguided. Instead of reinforcing gender stereotypes, feminist science studies scholars can formulate empirically testable hypotheses regarding local and contested beliefs about gender. In the second part of this article I argue that a social analysis of scientific knowledge is a key to understanding why the second and the third objections are misguided. The concept of gender is relevant for understanding the social practice of physics, and the social practice of physics can be of epistemic importance. Instead of advancing epistemic relativism, feminist science studies scholars can make important contributions to a subfield of philosophy called social epistemology.
Second harmonic generation microscopy
DEFF Research Database (Denmark)
Brüggemann, Dagmar Adeline; Brewer, Jonathan R.; Risbo, Jens
2010-01-01
Myofibers and collagen show non-linear optical properties enabling imaging using second harmonic generation (SHG) microscopy. The technique is evaluated for use as a tool for real-time studies of thermally induced changes in thin samples of unfixed and unstained pork. The forward and the backward...... scattered SHG light reveal complementary features of the structures of myofibers and collagen fibers. Upon heating the myofibers show no structural changes before reaching a temperature of 53 °C. At this temperature the SHG signal becomes extinct. The extinction of the SHG at 53 °C coincides with a low......-temperature endotherm peak observable in the differential scanning calorimetry (DSC) thermograms. DSC analysis of epimysium, the connective tissue layer that enfold skeletal muscles, produces one large endotherm starting at 57 °C and peaking at 59.5 °C. SHG microscopy of collagen fibers reveals a variability of thermal...
High order harmonic generation in rare gases
Energy Technology Data Exchange (ETDEWEB)
Budil, Kimberly Susan [Univ. of California, Davis, CA (United States)
1994-05-01
The process of high order harmonic generation in atomic gases has shown great promise as a method of generating extremely short wavelength radiation, extending far into the extreme ultraviolet (XUV). The process is conceptually simple. A very intense laser pulse (I ~10^{13}-10^{14} W/cm^{2}) is focused into a dense (~10^{17} particles/cm^{3}) atomic medium, causing the atoms to become polarized. These atomic dipoles are then coherently driven by the laser field and begin to radiate at odd harmonics of the laser field. This dissertation is a study of both the physical mechanism of harmonic generation as well as its development as a source of coherent XUV radiation. Recently, a semiclassical theory has been proposed which provides a simple, intuitive description of harmonic generation. In this picture the process is treated in two steps. The atom ionizes via tunneling after which its classical motion in the laser field is studied. Electron trajectories which return to the vicinity of the nucleus may recombine and emit a harmonic photon, while those which do not return will ionize. An experiment was performed to test the validity of this model wherein the trajectory of the electron as it orbits the nucleus or ion core is perturbed by driving the process with elliptically, rather than linearly, polarized laser radiation. The semiclassical theory predicts a rapid turn-off of harmonic production as the ellipticity of the driving field is increased. This decrease in harmonic production is observed experimentally and a simple quantum mechanical theory is used to model the data. The second major focus of this work was on development of the harmonic "source". A series of experiments were performed examining the spatial profiles of the harmonics. The quality of the spatial profile is crucial if the harmonics are to be used as the source for experiments, particularly if they must be refocused.
Energy Technology Data Exchange (ETDEWEB)
Suarez, J.A.; Mauro, G.F. di; Dimenna, C.; Anaut, D.; Aguero, C. [Universidad Nacional Mar del Plata (Argentina). Fac. de Ingenieria. Grupo LAT], e-mail: lat@mdp.edu.ar
2009-07-01
This paper analyzes potential variables that affect the neutral current when connected receivers presents nonlinear characteristics. Were simulated scenarios in the Alternative Transients Program combining the type and number of units loads, fed on sinusoidal voltages, symmetrical, balanced, asymmetrical and unbalanced. Also has been studied the effect of voltage harmonics. As a result of simulations with asymmetric and unbalanced sources was found variations in the neutral current up to 5%. Analysis of diversity effects and attenuation reported significant variances: 10% and 20% respectively. The results achieved show that asymmetries and imbalances in power have a slight impact on the neutral current, while the more prominent were the diversity and attenuation effects.
Understanding fifth-harmonic generation in CLBO
Patankar, S.; Yang, S. T.; Moody, J. D.; Bayramian, A. J.; Swadling, G. F.; Barker, D.; Datte, P.; Mennerat, G.; Norton, M.; Carr, C. W.; Begishev, I. A.; Bromage, J.; Ross, J. S.
2018-02-01
We report on results of fifth harmonic generation in Cesium Lithium Borate (CLBO) using a three-crystal cascaded frequency conversion scheme designed to study the energy balance of the final sum frequency generation stage. The experimental setup independently combines the first and fourth harmonic of a Nd:Glass laser in a 5mm thick CLBO crystal. Energy balance between the incoming and output energy is close to unity when the CLBO is out of phase matching and approximately 80% when the crystal is in phase matching. A detailed analysis of the residual fundamental and fourth harmonic energy indicates 5th harmonic light is being generated but only 26% is unaccounted for. We attribute the missing light to linear transmission loss in the CLBO oven. The ratio of the output to input energy is unity when the missing 5th harmonic is incorporated into the calculations. Two-dimensional plane wave mixing simulations show agreement with the results at lower intensities.
Energy Technology Data Exchange (ETDEWEB)
Cogo, Joao Roberto [Escola Federal de Engenharia de Itajuba, MG (Brazil)
1994-12-31
The non linear electrical loads can give rise to a number of disturbances in electrical power networks. Among them, the high consumption of relative power is to be noted and so is the several harmonic components which may be injected in the industry system and very often in the utility system. So, by using appropriate technical considerations, as well as measurements in typical special electrical loads, such negative effects are analyzed and ways of minimizing them are suggested. (author) 3 refs., 11 figs., 6 tabs.
Energy Technology Data Exchange (ETDEWEB)
Becker, Guenter; Johanson, Gunnar; Lindberg, Sandra; Vaurio, Jussi
2009-03-15
The Regulatory Code SSMFS 2008:1 of Swedish Radiation Safety Authority (SSM) includes requirements regarding the performance of probabilistic safety assessments (PSA), as well as PSA activities in general. Therefore, the follow-up of these activities is part of the inspection tasks of SSM. According to the SSMFS 2008:1, the safety analyses shall be based on a systematic identification and evaluation of such events, event sequences and other conditions which may lead to a radiological accident. The research report Nordic/German Working Group on Common cause Failure analysis. Phase 2 project report: Development of Harmonized Approach and Applications for Common Cause Failure Quantification has been developed under a contract with the Nordic PSA Group (NPSAG) and its German counterpart VGB, with the aim to create a common experience base for defence and analysis of dependent failures i.e. Common Cause Failures CCF. Phase 2 in this project if a deepened data analyses of CCF events and a demonstration on how the so called impact vectors can be constructed and on how CCF parameters are estimated. The word Guidance in the report title is used in order to indicate a common methodological guidance accepted by the NPSAG, based on current state of the art concerning the analysis of dependent failures and adapted to conditions relevant for Nordic sites. This will make it possible for the utilities to perform cost effective improvements and analyses. The report presents a common attempt by the authorities and the utilities to create a methodology and experience base for defence and analysis of dependent failures. The performed benchmark application has shown how important the interpretation of base data is to obtain robust CCF data and data analyses results. Good features were found in all benchmark approaches. The obtained experiences and approaches should now be used in harmonised procedures. A next step could be to develop and agree on event and formula driven impact vector
International Nuclear Information System (INIS)
Becker, Guenter; Johanson, Gunnar; Lindberg, Sandra; Vaurio, Jussi
2009-03-01
The Regulatory Code SSMFS 2008:1 of Swedish Radiation Safety Authority (SSM) includes requirements regarding the performance of probabilistic safety assessments (PSA), as well as PSA activities in general. Therefore, the follow-up of these activities is part of the inspection tasks of SSM. According to the SSMFS 2008:1, the safety analyses shall be based on a systematic identification and evaluation of such events, event sequences and other conditions which may lead to a radiological accident. The research report Nordic/German Working Group on Common cause Failure analysis. Phase 2 project report: Development of Harmonized Approach and Applications for Common Cause Failure Quantification has been developed under a contract with the Nordic PSA Group (NPSAG) and its German counterpart VGB, with the aim to create a common experience base for defence and analysis of dependent failures i.e. Common Cause Failures CCF. Phase 2 in this project if a deepened data analyses of CCF events and a demonstration on how the so called impact vectors can be constructed and on how CCF parameters are estimated. The word Guidance in the report title is used in order to indicate a common methodological guidance accepted by the NPSAG, based on current state of the art concerning the analysis of dependent failures and adapted to conditions relevant for Nordic sites. This will make it possible for the utilities to perform cost effective improvements and analyses. The report presents a common attempt by the authorities and the utilities to create a methodology and experience base for defence and analysis of dependent failures. The performed benchmark application has shown how important the interpretation of base data is to obtain robust CCF data and data analyses results. Good features were found in all benchmark approaches. The obtained experiences and approaches should now be used in harmonised procedures. A next step could be to develop and agree on event and formula driven impact vector
Electromagnetic cyclotron harmonic waves
International Nuclear Information System (INIS)
Ohnuma, T.; Watanabe, T.; Hamamatsu, K.
1981-09-01
Electromagnetic electron cyclotron harmonic waves just below the electron cyclotron harmonics are investigated numerically and experimentally. Backward waves which are observed to propagate nearly perpendicular to the magnetic field just below the electron cyclotron frequency in a high density magnetoplasma are confirmed to be in accord with the theoretical electromagnetic cyclotron waves. (author)
Harmonic Damping in DG-Penetrated Distribution Network
DEFF Research Database (Denmark)
Lu, Jinghang; Savaghebi, Mehdi; Guerrero, Josep M.
2016-01-01
Grid background harmonics may be amplified, propagate through a long distribution feeder and even lead to power system instability. In this paper, harmonic propagation issue is investigated and mitigation of the harmonics is analyzed by using transmission line theory which has already been applied...... in power systems. It is demonstrated that a specific harmonic will not be amplified if the feeder’s length is less than one quarter of the harmonic wavelength meanwhile the terminal impedance is less than characteristic impedance. Besides, three scenarios will be considered in accordance...... with the relationship between the feeder’s length and harmonic wavelength. Harmonic suppression control strategies will be respectively designed considering 5th and 7th harmonics coexisting in the distribution line. Finally, a simulation study has been performed to verify the theoretical analysis and demonstrate...
Directory of Open Access Journals (Sweden)
Yong Wang
2008-01-01
Full Text Available Noise characteristics of second-harmonic generation (SHG in periodically poled lithium niobate (PPLN using the quasiphase matching (QPM technique are analyzed experimentally. In the experiment, a0.78 μm second-harmonic (SH wave was generated when a 1.56 μm fundamental wave passed through a PPLN crystal (bulk or waveguide. The time-domain and frequency-domain noise characteristics of the fundamental and SH waves were analyzed. By using the pump-probe method, the noise characteristics of SHG were further analyzed when a visible light (532 nm and an infrared light (1090 nm copropagated with the fundamental light, respectively. The noise characterizations were also investigated at different temperatures. It is found that for the bulk and waveguide PPLN crystals, the SH wave has a higher relative noise level than the corresponding fundamental wave. For the same fundamental wave, the SH wave has lower noise in a bulk crystal than in a waveguide, and in MgO-doped PPLN than in undoped PPLN. The 532 nm irradiation can lead to higher noise in PPLN than the 1090 nm irradiation. In addition, increasing temperature of device can alleviate the problem of noise in conjunction with the photorefractive effect incurred by the irradiation light. This is more significant in undoped PPLN than in MgO-doped one.
Operational reactor physics analysis codes (ORPAC)
International Nuclear Information System (INIS)
Kumar, Jainendra; Singh, K.P.; Singh, Kanchhi
2007-07-01
For efficient, smooth and safe operation of a nuclear research reactor, many reactor physics evaluations are regularly required. As part of reactor core management the important activities are maintaining core reactivity status, core power distribution, xenon estimations, safety evaluation of in-pile irradiation samples and experimental assemblies and assessment of nuclear safety in fuel handling/storage. In-pile irradiation of samples requires a prior estimation of the reactivity load due to the sample, the heating rate and the activity developed in it during irradiation. For the safety of personnel handling irradiated samples the dose rate at the surface of shielded flask housing the irradiated sample should be less than 200 mR/Hr.Therefore, a proper shielding and radioactive cooling of the irradiated sample are required to meet the said requirement. Knowledge of xenon load variation with time (Startup-curve) helps in estimating Xenon override time. Monitoring of power in individual fuel channels during reactor operation is essential to know any abnormal power distribution to avoid unsafe situations. Complexities in the estimation of above mentioned reactor parameters and their frequent requirement compel one to use computer codes to avoid possible human errors. For efficient and quick evaluation of parameters related to reactor operations such as xenon load, critical moderator height and nuclear heating and reactivity load of isotope samples/experimental assembly, a computer code ORPAC (Operational Reactor Physics Analysis Codes) has been developed. This code is being used for regular assessment of reactor physics parameters in Dhruva and Cirus. The code ORPAC written in Visual Basic 6.0 environment incorporates several important operational reactor physics aspects on a single platform with graphical user interfaces (GUI) to make it more user-friendly and presentable. (author)
Data analysis for physical scientists featuring Excel
Kirkup, Les
2012-01-01
The ability to summarise data, compare models and apply computer-based analysis tools are vital skills necessary for studying and working in the physical sciences. This textbook supports undergraduate students as they develop and enhance these skills. Introducing data analysis techniques, this textbook pays particular attention to the internationally recognised guidelines for calculating and expressing measurement uncertainty. This new edition has been revised to incorporate Excel® 2010. It also provides a practical approach to fitting models to data using non-linear least squares, a powerful technique which can be applied to many types of model. Worked examples using actual experimental data help students understand how the calculations apply to real situations. Over 200 in-text exercises and end-of-chapter problems give students the opportunity to use the techniques themselves and gain confidence in applying them. Answers to the exercises and problems are given at the end of the book.
Kawata, Masaaki; Sato, Chikara
2007-06-01
In determining the three-dimensional (3D) structure of macromolecular assemblies in single particle analysis, a large representative dataset of two-dimensional (2D) average images from huge number of raw images is a key for high resolution. Because alignments prior to averaging are computationally intensive, currently available multireference alignment (MRA) software does not survey every possible alignment. This leads to misaligned images, creating blurred averages and reducing the quality of the final 3D reconstruction. We present a new method, in which multireference alignment is harmonized with classification (multireference multiple alignment: MRMA). This method enables a statistical comparison of multiple alignment peaks, reflecting the similarities between each raw image and a set of reference images. Among the selected alignment candidates for each raw image, misaligned images are statistically excluded, based on the principle that aligned raw images of similar projections have a dense distribution around the correctly aligned coordinates in image space. This newly developed method was examined for accuracy and speed using model image sets with various signal-to-noise ratios, and with electron microscope images of the Transient Receptor Potential C3 and the sodium channel. In every data set, the newly developed method outperformed conventional methods in robustness against noise and in speed, creating 2D average images of higher quality. This statistically harmonized alignment-classification combination should greatly improve the quality of single particle analysis.
Energy Technology Data Exchange (ETDEWEB)
Chao, Ong Zhi; Cheet, Lim Hong; Yee, Khoo Shin [Mechanical Engineering Department, Faculty of EngineeringUniversity of Malaya, Kuala Lumpur (Malaysia); Rahman, Abdul Ghaffar Abdul [Faculty of Mechanical Engineering, University Malaysia Pahang, Pekan (Malaysia); Ismail, Zubaidah [Civil Engineering Department, Faculty of Engineering, University of Malaya, Kuala Lumpur (Malaysia)
2016-08-15
A novel method called Impact-synchronous modal analysis (ISMA) was proposed previously which allows modal testing to be performed during operation. This technique focuses on signal processing of the upstream data to provide cleaner Frequency response function (FRF) estimation prior to modal extraction. Two important parameters, i.e., windowing function and impact force level were identified and their effect on the effectiveness of this technique were experimentally investigated. When performing modal testing during running condition, the cyclic loads signals are dominant in the measured response for the entire time history. Exponential window is effectively in minimizing leakage and attenuating signals of non-synchronous running speed, its harmonics and noises to zero at the end of each time record window block. Besides, with the information of the calculated cyclic force, suitable amount of impact force to be applied on the system could be decided prior to performing ISMA. Maximum allowable impact force could be determined from nonlinearity test using coherence function. By applying higher impact forces than the cyclic loads along with an ideal decay rate in ISMA, harmonic reduction is significantly achieved in FRF estimation. Subsequently, the dynamic characteristics of the system are successfully extracted from a cleaner FRF and the results obtained are comparable with Experimental modal analysis (EMA)
Molina-Aguilera, A.; Mancilla, F. D. L.; Julià, J.; Morales, J.
2017-12-01
Joint inversion techniques of P-receiver functions and wave dispersion data implicitly assume an isotropic radial stratified earth. The conventional approach invert stacked radial component receiver functions from different back-azimuths to obtain a laterally homogeneous single-velocity model. However, in the presence of strong lateral heterogeneities as anisotropic layers and/or dipping interfaces, receiver functions are considerably perturbed and both the radial and transverse components exhibit back azimuthal dependences. Harmonic analysis methods exploit these azimuthal periodicities to separate the effects due to the isotropic flat-layered structure from those effects caused by lateral heterogeneities. We implement a harmonic analysis method based on radial and transverse receiver functions components and carry out a synthetic study to illuminate the capabilities of the method in isolating the isotropic flat-layered part of receiver functions and constrain the geometry and strength of lateral heterogeneities. The independent of the baz P receiver function are jointly inverted with phase and group dispersion curves using a linearized inversion procedure. We apply this approach to high dense seismic profiles ( 2 km inter-station distance, see figure) located in the central Betics (western Mediterranean region), a region which has experienced complex geodynamic processes and exhibit strong variations in Moho topography. The technique presented here is robust and can be applied systematically to construct a 3-D model of the crust and uppermost mantle across large networks.
International Nuclear Information System (INIS)
Chao, Ong Zhi; Cheet, Lim Hong; Yee, Khoo Shin; Rahman, Abdul Ghaffar Abdul; Ismail, Zubaidah
2016-01-01
A novel method called Impact-synchronous modal analysis (ISMA) was proposed previously which allows modal testing to be performed during operation. This technique focuses on signal processing of the upstream data to provide cleaner Frequency response function (FRF) estimation prior to modal extraction. Two important parameters, i.e., windowing function and impact force level were identified and their effect on the effectiveness of this technique were experimentally investigated. When performing modal testing during running condition, the cyclic loads signals are dominant in the measured response for the entire time history. Exponential window is effectively in minimizing leakage and attenuating signals of non-synchronous running speed, its harmonics and noises to zero at the end of each time record window block. Besides, with the information of the calculated cyclic force, suitable amount of impact force to be applied on the system could be decided prior to performing ISMA. Maximum allowable impact force could be determined from nonlinearity test using coherence function. By applying higher impact forces than the cyclic loads along with an ideal decay rate in ISMA, harmonic reduction is significantly achieved in FRF estimation. Subsequently, the dynamic characteristics of the system are successfully extracted from a cleaner FRF and the results obtained are comparable with Experimental modal analysis (EMA)
Transient regime in second harmonic generation
Szeftel, Jacob; Sandeau, Laure; Sandeau, Nicolas; Delezoide, Camille; Khater, Antoine
2013-09-01
The time growth of the electromagnetic field at the fundamental and double frequencies is studied from the very onset of the second harmonic generation (SHG) process for a set of dipoles lacking a symmetry centre and exhibiting a nonresonant coupling with a classical electromagnetic field. This approach consists first of solving the Schrödinger equation by applying a generalised Rabi rotation to the Hamiltonian describing the light-dipole interaction. This rotation has been devised for the resulting Hamiltonian to show up time-independent for both components of the electromagnetic field at the fundamental frequency and the second harmonic one. Then an energy conservation argument, derived from the Poynting theorem, is introduced to work out an additional relationship between the electromagnetic field and its associated electric polarisation. Finally this analysis yields the full time behaviour of all physical quantities of interest. The calculated results reproduce accurately both the observed spatial oscillations of the SHG intensity (Maker's fringes) and its power law dependence on the intensity of the incoming light at the fundamental frequency.
Challenges and Opportunities for Harmonizing Research Methodology
DEFF Research Database (Denmark)
van Hees, V. T.; Thaler-Kall, K.; Wolf, K. H.
2016-01-01
Objectives: Raw accelerometry is increasingly being used in physical activity research, but diversity in sensor design, attachment and signal processing challenges the comparability of research results. Therefore, efforts are needed to harmonize the methodology. In this article we reflect on how...... increased methodological harmonization may be achieved. Methods: The authors of this work convened for a two-day workshop (March 2014) themed on methodological harmonization of raw accelerometry. The discussions at the workshop were used as a basis for this review. Results: Key stakeholders were identified...... as manufacturers, method developers, method users (application), publishers, and funders. To facilitate methodological harmonization in raw accelerometry the following action points were proposed: i) Manufacturers are encouraged to provide a detailed specification of their sensors, ii) Each fundamental step...
Bayesian data analysis tools for atomic physics
Trassinelli, Martino
2017-10-01
We present an introduction to some concepts of Bayesian data analysis in the context of atomic physics. Starting from basic rules of probability, we present the Bayes' theorem and its applications. In particular we discuss about how to calculate simple and joint probability distributions and the Bayesian evidence, a model dependent quantity that allows to assign probabilities to different hypotheses from the analysis of a same data set. To give some practical examples, these methods are applied to two concrete cases. In the first example, the presence or not of a satellite line in an atomic spectrum is investigated. In the second example, we determine the most probable model among a set of possible profiles from the analysis of a statistically poor spectrum. We show also how to calculate the probability distribution of the main spectral component without having to determine uniquely the spectrum modeling. For these two studies, we implement the program Nested_fit to calculate the different probability distributions and other related quantities. Nested_fit is a Fortran90/Python code developed during the last years for analysis of atomic spectra. As indicated by the name, it is based on the nested algorithm, which is presented in details together with the program itself.
Analysis of new physics in B decays
Energy Technology Data Exchange (ETDEWEB)
Feger, Robert
2010-03-26
The inclusive semileptonic decay B{yields}X{sub c}l{nu} yields the best extracted value of vertical stroke V{sub cb} vertical stroke with an uncertainty of about 2%, which is due to its precise theoretical description by the heavy-quark expansion (HQE) and the large amount of data collected by the B factories Babar and Belle. Besides the precision determination of vertical stroke V{sub cb} vertical stroke and the HQE parameter it also enables us to test for new physics effects. Normal decays with a small standard model contribution are investigated on the quest for new physics, like flavour-changing neutral currents, which are suppressed in the standard model by the GIM mechanism. But as right-handed weak currents are absent in the standard model their appearance would be a smoking gun signal for new physics in the decay considered here. We perform such an analysis, which is known form the leptonic sector as ''Michel parameter analysis''. Contributions from possible new physics effects are derived with effective field theory methods, yielding an enhanced b {yields} c current, with not only a right-handed vector contribution, but also scalar and tensor couplings. We repeat the computations of the decay with the enhanced current up to O(1/m{sub b}{sup 2}) in the HQE and up to O({alpha}{sub s}) in the perturbative corrections. A moment analysis of the moments of the lepton energy spectrum and the hadronic invariant mass has become a reliable tool in both the theoretical evaluation and the experimental determination. This combines in a HQE fit, which has been improved frequently, yielding a precise determination of the HQE parameters and especially the best extracted value for vertical stroke V{sub cb} vertical stroke. The HQE fit may as well serve as a test for new physics effects in these moments. The theoretical analysis of the moments reveals a low sensitivity of the moments on the non-vector currents. Thus we perform the fit with only a
Double Harmonic Transmission (D.H.T.
Directory of Open Access Journals (Sweden)
Sava Ianici
2006-10-01
Full Text Available The paper presents the construction and functioning of a new type of harmonic drive named double harmonic transmission (D.H.T.. In the second part of this paper is presented the dynamic analysis of the double harmonic transmission, which is based on the results of the experimental researches on the D.H.T. This study of the stress status and the forces distribution is necessary for to determine the durability on the portant elements of the D.H.T.
Judd, Nicolas; Smith, Jason; Jain, Manu; Mukherjee, Sushmita; Icaza, Michael; Gallagher, Ryan; Szeligowski, Richard; Wu, Binlin
2018-02-01
A clear distinction between oncocytoma and chromophobe renal cell carcinoma (chRCC) is critically important for clinical management of patients. But it may often be difficult to distinguish the two entities based on hematoxylin and eosin (H and E) stained sections alone. In this study, second harmonic generation (SHG) signals which are very specific to collagen were used to image collagen fibril structure. We conduct a pilot study to develop a new diagnostic method based on the analysis of collagen associated with kidney tumors using convolutional neural networks (CNNs). CNNs comprise a type of machine learning process well-suited for drawing information out of images. This study examines a CNN model's ability to differentiate between oncocytoma (benign), and chRCC (malignant) kidney tumor images acquired with second harmonic generation (SHG), which is very specific for collagen matrix. To the best of our knowledge, this is the first study that attempts to distinguish the two entities based on their collagen structure. The model developed from this study demonstrated an overall classification accuracy of 68.7% with a specificity of 66.3% and sensitivity of 74.6%. While these results reflect an ability to classify the kidney tumors better than chance, further studies will be carried out to (a) better realize the tumor classification potential of this method with a larger sample size and (b) combining SHG with two-photon excited intrinsic fluorescence signal to achieve better classification.
International Nuclear Information System (INIS)
Lin, Qui-xun; Van Wechel, T.D.
1987-01-01
A single gap harmonic buncher has been constructed as a pretandem buncher. Over 85% of a proton dc beam has been bunched into pulses. The width (fwhm) of the pulses is 0.7 ns. The buncher is based on that built at Argonne. Changes were made to the buncher's configuration so that the buncher could be tuned to the desired four harmonic frequencies. A method of calibrating and setting the relative phases and amplitudes of the four harmonic frequencies has been used to obtain an optimum sawtooth-like bunching waveform
Harmonic supergraphs. Green functions
International Nuclear Information System (INIS)
Galperin, A.; Ivanov, E.; Gievetsky, V.; Sokatchev, E.
1985-01-01
The quantization procedure in the harmonic superspace approach is worked out. Harmonic distributions are introduced and are used to construct the analytic superspace delta-functions and the Green functions for the hypermultiplet and the N=2 Yang-Mills superfields. The gauge fixing is described and the relevant Faddeev-Popov ghosts are defined. The corresponding BRST transformations are found. The harmonic superspace quantization of the N=2 gauge theory turns out to be rather simple and has many parallels with that for the standard (N=0) Yang-Mills theory. In particular, no ghosts-forghosts are needed
Sequence Domain Harmonic Modeling of Type-IV Wind Turbines
DEFF Research Database (Denmark)
Guest, Emerson; Jensen, Kim Høj; Rasmussen, Tonny Wederberg
2017-01-01
-sampled pulsewidth modulation and an analysis of converter generated voltage harmonics due to compensated dead-time. The decoupling capabilities of the proposed the SD harmonic model are verified through a power quality (PQ) assessment of a 3MW Type-IV wind turbine. The assessment shows that the magnitude and phase...... of low-order odd converter generated voltage harmonics are dependent on the converter operating point and the phase of the fundamental component of converter current respectively. The SD harmonic model can be used to make PQ assessments of Type-IV wind turbines or incorporated into harmonic load flows...... for computation of PQ in wind power plants....
International Nuclear Information System (INIS)
Marhavilas, P.K.; Koulouriotis, D.E.; Spartalis, S.H.
2013-01-01
The development of an integrated risk analysis scheme, which will combine a well-considered selection of widespread techniques, would enable the companies to achieve efficient results on risk assessment. In this study, we develop a methodological framework (as a part of the quantified risk evaluation), by incorporating a new technique, that is implemented by the harmonic-analysis of time-series of occupational-accidents (called as HATS). Our objective is therefore, twofold: (i) the development of a new risk assessment framework (HATS technique) and the subsequent application of HATS on the worksites of electric power industry and construction sector, and (ii) the enrichment of the harmonic-analysis theoretical background, as far as the significance-level of spectral peaks is concerned, with fully-completed practical tables, that they have been produced by using the scientific literature. In fact, we apply HATS on occupational-accident time-series, which were (a) observed in the worksites of the Greek Public electric Power Corporation (PPC) and the Greek construction-companies (GCCs), and (b) recorded in great statistical-databases of PPC, and IKA (the Greek Social Insurance Institute/Ministry of Health), respectively. The results of HATS were tested statistically by using Shimshoni's significance-test. Moreover, the results of the comparative time/frequency-domain analysis of the accident time-series in PPC (for 1993–2009) and GCCs (for 1999–2007), prove that they are characterized by the existence of a periodic factor which (a) constitutes a permanent feature for the dynamic behavior of PPC's and GCCs' OHSS (occupational health and safety system), and (b) could be taken into account by risk managers in risk assessment, i.e., immediate suppressive measures must be taken place to abolish the danger source which is originated from the quasi-periodic appearance of the most important hazard sources
XML-based analysis interface for particle physics data analysis
International Nuclear Information System (INIS)
Hu Jifeng; Lu Xiaorui; Zhang Yangheng
2011-01-01
The letter emphasizes on an XML-based interface and its framework for particle physics data analysis. The interface uses a concise XML syntax to describe, in data analysis, the basic tasks: event-selection, kinematic fitting, particle identification, etc. and a basic processing logic: the next step goes on if and only if this step succeeds. The framework can perform an analysis without compiling by loading the XML-interface file, setting p in run-time and running dynamically. An analysis coding in XML instead of C++, easy-to-understood arid use, effectively reduces the work load, and enables users to carry out their analyses quickly. The framework has been developed on the BESⅢ offline software system (BOSS) with the object-oriented C++ programming. These functions, required by the regular tasks and the basic processing logic, are implemented with both standard modules or inherited from the modules in BOSS. The interface and its framework have been tested to perform physics analysis. (authors)
XUV pulse effect on signal modulations of harmonic spectra from H ...
Indian Academy of Sciences (India)
LIQIANG FENG
2018-03-24
Mar 24, 2018 ... 2Laboratory of Modern Physics, Liaoning University of Technology, ... Molecular high-order harmonic generation; amplitude modulation of harmonics; frequency .... Here, mp, R and z are the mass of H or T, the internu-.
International Nuclear Information System (INIS)
Caetano Neto, E.S.
1976-01-01
A stationary Green function is calculated for the Schroedinger Hamiltonian of the multidimensional isotropic harmonic oscillator and for physical systems, which may, somehow, have their Hamiltonian reduced to one in the form of a harmonic oscillator, for any dimension [pt
Superstrings and harmonic superspace
International Nuclear Information System (INIS)
Kallosh, R.E.; AN SSSR, Moscow. Fizicheskij Inst.)
1987-01-01
The paper on superstrings and harmonic superspace is a contribution to the book dedicated to E.S. Fradkin on his sixtieth birthday. The purpose of the paper is to propose a description of N = 2,3 superspace which could be used for the investigation of the effective d = 10 harmonic superspace corresponding to the heterotic superstring. A description is given of the structure of semi-simple Lie algebras in the Cartan-Weyl basis, as well as the general properties of the even, compact part of harmonic superspace. The main properties of the four-dimensional N = 2 SYM theory are discussed, along with the N = 3, d = 4 super Yang-Mills theory. Finally the relation between the harmonic superspace and the heterotic E 8 x E 8 superstring is examined. (U.K.)
Harmonic excitations in quasicrystals
International Nuclear Information System (INIS)
Luck, J.M.
1986-03-01
The harmonic excitations (phonons) of quasicrystals are studied in a simple one-dimensional model. The spectrum is a Cantor set, which exhibits selfsimilarity properties. The eigenstates are generically ''critical'', i.e. neither extended nor localized
Energy Technology Data Exchange (ETDEWEB)
Hohmann, Manuel [Physikalisches Institut, Universitaet Tartu (Estonia)
2016-07-01
Tensor harmonics are a useful mathematical tool for finding solutions to differential equations which transform under a particular representation of the rotation group SO(3). In order to make use of this tool also in the setting of Finsler geometry, where the objects of relevance are d-tensors instead of tensors, we construct a set of d-tensor harmonics for both SO(3) and SO(4) symmetries and show how these can be used for calculations in Finsler geometry and gravity.
Harmonic distortion in microwave photonic filters.
Rius, Manuel; Mora, José; Bolea, Mario; Capmany, José
2012-04-09
We present a theoretical and experimental analysis of nonlinear microwave photonic filters. Far from the conventional condition of low modulation index commonly used to neglect high-order terms, we have analyzed the harmonic distortion involved in microwave photonic structures with periodic and non-periodic frequency responses. We show that it is possible to design microwave photonic filters with reduced harmonic distortion and high linearity even under large signal operation.
The methodology of semantic analysis for extracting physical effects
Fomenkova, M. A.; Kamaev, V. A.; Korobkin, D. M.; Fomenkov, S. A.
2017-01-01
The paper represents new methodology of semantic analysis for physical effects extracting. This methodology is based on the Tuzov ontology that formally describes the Russian language. In this paper, semantic patterns were described to extract structural physical information in the form of physical effects. A new algorithm of text analysis was described.
Stability and nonlinear dynamics of gyrotrons at cyclotron harmonics
International Nuclear Information System (INIS)
Saraph, G.P.; Nusinovich, G.S.; Antonsen, T.M. Jr.; Levush, B.
1992-01-01
Gyrotrons operating at higher harmonics of the cyclotron frequency can overcome the frequency limitations caused by achievable strength of the magnetic field. However, the excitation of modes at the fundamental frequency exhibit a major problem for stable operation of harmonic gyrotron at high power with high efficiency. Therefore the issues of stability of gyrotron operation at the cyclotron harmonics and nonlinear dynamics of mode interaction are of great importance. The results of the authors stability analysis and multimode simulation are presented here. A detailed nonlinear theory of steady state single mode operation at cyclotron harmonics has been presented previously, taking into account beam-wave coupling and nonlinear gain function at cyclotron harmonics. A set of equations describing low gain regime interaction of modes resonant at different cyclotron harmonics was studied before. The multifrequency time-dependent nonlinear analysis presented here is based on previous gyrotron studies and beam-wave interaction at cyclotron harmonics. The authors have determined the parameter space for stable single mode operation at the second harmonic. The nonlinear dynamics of mode evolution and mode interaction for a harmonic gyrotron is presented. A new nonlinear effect in which the parasite at the fundamental harmonic helps excite the operating mode at the second harmonic has been demonstrated
Optical High Harmonic Generation in C60
Zhang, Guoping
2005-03-01
C60 et al. Physical Review Letters Physical Review B High harmonic generation (HHG) requires a strong laser field, but in a relatively weak laser field is sufficient. Numerical results presented here show while its low order harmonics result from the laser field, its high order ones are mainly from the multiple excitations. Since high order harmonics directly correlate electronic transitions, the HHG spectrum accurately measures transition energies. Therefore, is not only a promising material for HHG, but may also present an opportunity to develop HHG into an electronic structure probing tool. References: G. P. Zhang, 91, 176801 (2003); G. P. Zhang and T. F. George, 68, 165410 (2003); P. B. Corkum, 71, 1994 (1993); G. P. Zhang and Thomas F. George, 93, 147401 (2004); H. Niikura ,ature 417, 917 (2002); ibid. 421, 826 (2003); Y. Mairesse ,cience 302, 1540 (2003); A. Baltuska ,ature 421, 611 (2003).
Al-Shudeifat, Mohammad A.; Butcher, Eric A.
2011-01-01
The actual breathing mechanism of the transverse breathing crack in the cracked rotor system that appears due to the shaft weight is addressed here. As a result, the correct time-varying area moments of inertia for the cracked element cross-section during shaft rotation are also determined. Hence, two new breathing functions are identified to represent the actual breathing effect on the cracked element stiffness matrix. The new breathing functions are used in formulating the time-varying finite element stiffness matrix of the cracked element. The finite element equations of motion are then formulated for the cracked rotor system and solved via harmonic balance method for response, whirl orbits and the shift in the critical and subcritical speeds. The analytical results of this approach are compared with some previously published results obtained using approximate formulas for the breathing mechanism. The comparison shows that the previously used breathing function is a weak model for the breathing mechanism in the cracked rotor even for small crack depths. The new breathing functions give more accurate results for the dynamic behavior of the cracked rotor system for a wide range of the crack depths. The current approach is found to be efficient for crack detection since the critical and subcritical shaft speeds, the unique vibration signature in the neighborhood of the subcritical speeds and the sensitivity to the unbalance force direction all together can be utilized to detect the breathing crack before further damage occurs.
International Nuclear Information System (INIS)
Civalek, Oemer
2005-01-01
The nonlinear dynamic response of doubly curved shallow shells resting on Winkler-Pasternak elastic foundation has been studied for step and sinusoidal loadings. Dynamic analogues of Von Karman-Donnel type shell equations are used. Clamped immovable and simply supported immovable boundary conditions are considered. The governing nonlinear partial differential equations of the shell are discretized in space and time domains using the harmonic differential quadrature (HDQ) and finite differences (FD) methods, respectively. The accuracy of the proposed HDQ-FD coupled methodology is demonstrated by numerical examples. The shear parameter G of the Pasternak foundation and the stiffness parameter K of the Winkler foundation have been found to have a significant influence on the dynamic response of the shell. It is concluded from the present study that the HDQ-FD methodolgy is a simple, efficient, and accurate method for the nonlinear analysis of doubly curved shallow shells resting on two-parameter elastic foundation
Directory of Open Access Journals (Sweden)
Yulu Huang
2016-08-01
Full Text Available An ultrafast kicker system is being developed for the energy recovery linac (ERL based electron circulator cooler ring (CCR in the proposed Jefferson Lab Electron Ion Collider (JLEIC, previously named MEIC. In the CCR, the injected electron bunches can be recirculated while performing ion cooling for 10–30 turns before the extraction, thus reducing the recirculation beam current in the ERL to 1/10−1/30 (150 mA-50 mA of the cooling beam current (up to 1.5 A. Assuming a bunch repetition rate of 476.3 MHz and a recirculating factor of 10 in the CCR, the kicker is required to operate at a pulse repetition rate of 47.63 MHz with pulse width of around 2 ns, so that only every 10th bunch in the CCR will experience a transverse kick while the rest of the bunches will not be disturbed. Such a kicker pulse can be synthesized by ten harmonic modes of the 47.63 MHz kicker pulse repetition frequency, using up to four quarter wavelength resonator (QWR based deflecting cavities. In this paper, several methods to synthesize such a kicker waveform will be discussed and a comparison of their beam dynamics performance is made using ELEGANT. Four QWR cavities are envisaged with high transverse shunt impedance requiring less than 100 W of total rf power for a Flat-Top kick pulse. Multipole fields due to the asymmetry of this type of cavity are analyzed. The transverse emittance growth due to the sextupole component is simulated in ELEGANT. Off-axis injection and extraction issues and beam optics using a multicavity kick-drift scheme will also be discussed.
Energy Technology Data Exchange (ETDEWEB)
Song, Ting [State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Lanzhou University of Technology, Lanzhou 730050 (China); School of Mathematics and Physics, Lanzhou Jiaotong University, Lanzhou 730070 (China); Ma, Qin, E-mail: maqin_lut@yeah.net [State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Lanzhou University of Technology, Lanzhou 730050 (China); Sun, Xiao-Wei [School of Mathematics and Physics, Lanzhou Jiaotong University, Lanzhou 730070 (China); Liu, Zi-Jiang [School of Mathematics and Physics, Lanzhou Jiaotong University, Lanzhou 730070 (China); Department of Physics, Lanzhou City University, Lanzhou 730070 (China); Wei, Xiao-Ping [School of Mathematics and Physics, Lanzhou Jiaotong University, Lanzhou 730070 (China); Tian, Jun-Hong [School of Mathematics and Physics, Lanzhou Jiaotong University, Lanzhou 730070 (China); Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065 (China)
2017-02-15
First-principles calculations based on density functional theory and quasi-harmonic Debye model are used to investigate the high-pressure and high-temperature physical properties, including the lattice constant, magnetic moment, density of states, pressure-volume-temperature relationship, bulk modulus, thermal expansivity, heat capacity, and Grüneisen parameter for the new Mn-based full-Heusler alloy Mn{sub 2}RuSi in CuHg{sub 2}Ti-type structure. The optimized equilibrium lattice constant is consistent with experimental and other theoretical results. The calculated total spin magnetic moment remains an integral value of 2.0 μ{sub B} in the lattice constant range of 5.454–5.758 Å, and then decreases very slowly with the decrease of lattice constant to 5.333 Å. By the spin resolved density of states calculations, we have shown that Mn{sub 2}RuSi compound presents half-metallic ferrimagnetic properties under the equilibrium lattice constant. The effects of temperature and pressure on bulk modulus, thermal expansivity, heat capacity, and Grüneisen parameter are opposite, which are consistent with a compression rate of volume. Furthermore, the results show that the effect of temperature is larger than pressure for heat capacity and the effect of high temperature and pressure on thermal expansion coefficient is small. All the properties of Mn{sub 2}RuSi alloy are summarized in the pressure range of 0–100 GPa and the temperature up to 1200 K. - Highlights: • High-pressure and high-temperature physical properties of Mn2RuSi were investigated. • Ferrimagnetic ground state has been confirmed in Mn2RuSi alloy. • The first-principle calculations and quasi-harmonic Debye model were used. • The pressure up to 100 GPa and the temperature up to 1200 K.
Harmonic generation with multiple wiggler schemes
Energy Technology Data Exchange (ETDEWEB)
Bonifacio, R.; De Salvo, L.; Pierini, P. [Universita degli Studi, Milano (Italy)
1995-02-01
In this paper the authors give a simple theoretical description of the basic physics of the single pass high gain free electron laser (FEL), describing in some detail the FEL bunching properties and the harmonic generation technique with a multiple-wiggler scheme or a high gain optical klystron configuration.
Moreno, Jackeline; Vogeley, Michael S.; Richards, Gordon; O'Brien, John T.; Kasliwal, Vishal
2018-01-01
We present rigorous testing of survey cadences (K2, SDSS, CRTS, & Pan-STARRS) for quasar variability science using a magnetohydrodynamics synthetic lightcurve and the canonical lightcurve from Kepler, Zw 229.15. We explain where the state of the art is in regards to physical interpretations of stochastic models (CARMA) applied to AGN variability. Quasar variability offers a time domain approach of probing accretion physics at the SMBH scale. Evidence shows that the strongest amplitude changes in the brightness of AGN occur on long timescales ranging from months to hundreds of days. These global behaviors can be constrained by survey data despite low sampling resolution. CARMA processes provide a flexible family of models used to interpolate between data points, predict future observations and describe behaviors in a lightcurve. This is accomplished by decomposing a signal into rise and decay timescales, frequencies for cyclic behavior and shock amplitudes. Characteristic timescales may point to length-scales over which a physical process operates such as turbulent eddies, warping or hotspots due to local thermal instabilities. We present the distribution of SDSS Stripe 82 quasars in CARMA parameters space that pass our cadence tests and also explain how the Damped Harmonic Oscillator model, CARMA(2,1), reduces to the Damped Random Walk, CARMA(1,0), given the data in a specific region of the parameter space.
Fuller, Robert G., Ed.; And Others
This is part of a series of 42 Calculus Based Physics (CBP) modules totaling about 1,000 pages. The modules include study guides, practice tests, and mastery tests for a full-year individualized course in calculus-based physics based on the Personalized System of Instruction (PSI). The units are not intended to be used without outside materials;…
CSIR Research Space (South Africa)
Grobler, TL
2012-06-01
Full Text Available . The Fourier transform and maximum-likelihood parameter estimation are used to estimate the harmonic and noise parameters of the colored simple harmonic oscillator. Two case studies in South Africa show that reliable class differentiation can be obtained...
The Local Stellar Velocity Field via Vector Spherical Harmonics
Markarov, V. V.; Murphy, D. W.
2007-01-01
We analyze the local field of stellar tangential velocities for a sample of 42,339 nonbinary Hipparcos stars with accurate parallaxes, using a vector spherical harmonic formalism. We derive simple relations between the parameters of the classical linear model (Ogorodnikov-Milne) of the local systemic field and low-degree terms of the general vector harmonic decomposition. Taking advantage of these relationships, we determine the solar velocity with respect to the local stars of (V(sub X), V(sub Y), V(sub Z)) (10.5, 18.5, 7.3) +/- 0.1 km s(exp -1) not corrected for the asymmetric drift with respect to the local standard of rest. If only stars more distant than 100 pc are considered, the peculiar solar motion is (V(sub X), V(sub Y), V(sub Z)) (9.9, 15.6, 6.9) +/- 0.2 km s(exp -1). The adverse effects of harmonic leakage, which occurs between the reflex solar motion represented by the three electric vector harmonics in the velocity space and higher degree harmonics in the proper-motion space, are eliminated in our analysis by direct subtraction of the reflex solar velocity in its tangential components for each star. The Oort parameters determined by a straightforward least-squares adjustment in vector spherical harmonics are A=14.0 +/- 1.4, B=13.1 +/- 1.2, K=1.1 +/- 1.8, and C=2.9 +/- 1.4 km s(exp -1) kpc(exp -1). The physical meaning and the implications of these parameters are discussed in the framework of a general linear model of the velocity field. We find a few statistically significant higher degree harmonic terms that do not correspond to any parameters in the classical linear model. One of them, a third-degree electric harmonic, is tentatively explained as the response to a negative linear gradient of rotation velocity with distance from the Galactic plane, which we estimate at approximately -20 km s(exp -1) kpc(exp -1). A similar vertical gradient of rotation velocity has been detected for more distant stars representing the thick disk (z greater than 1 kpc
International Nuclear Information System (INIS)
Saraph, G.P.; Antonsen, T.M. Jr.; Nusinovich, G.S.; Levush, B.
1995-01-01
Mode competition can present a major hurdle in achieving stable, efficient operation of a gyrotron at the cyclotron harmonics. A type of mode interaction in which three modes at different cyclotron harmonics are parametrically coupled together is analyzed here. This coupling can lead to parametric excitation or suppression of a mode; cyclic mode hopping; or the coexistence of three modes. Simulation results are presented for the parametric instability involving modes at the fundamental, second harmonic, and third harmonic of the cyclotron frequency. It is shown that the parametric excitation can lead to stable, efficient operation of a high-power gyrotron at the third harmonic. Based on this phenomenon, two practical designs are presented here for the third harmonic operation at 94 and 210 GHz. copyright 1995 American Institute of Physics
Harmonization versus Mutual Recognition
DEFF Research Database (Denmark)
Jørgensen, Jan Guldager; Schröder, Philipp
The present paper examines trade liberalization driven by the coordination of product standards. For oligopolistic firms situated in separate markets that are initially sheltered by national standards, mutual recognition of standards implies entry and reduced profits at home paired with the oppor......The present paper examines trade liberalization driven by the coordination of product standards. For oligopolistic firms situated in separate markets that are initially sheltered by national standards, mutual recognition of standards implies entry and reduced profits at home paired...... countries and three firms, where firms first lobby for the policy coordination regime (harmonization versus mutual recognition), and subsequently, in case of harmonization, the global standard is auctioned among the firms. We discuss welfare effects and conclude with policy implications. In particular......, harmonized standards may fail to harvest the full pro-competitive effects from trade liberalization compared to mutual recognition; moreover, the issue is most pronounced in markets featuring price competition....
Bennett, Charles L.
2016-03-22
A reciprocating-piston uniflow engine includes a harmonic oscillator inlet valve capable of oscillating at a resonant frequency for controlling the flow of working fluid into the engine. In particular, the inlet valve includes an inlet valve head and a spring arranged together as a harmonic oscillator so that the inlet valve head is moveable from an unbiased equilibrium position to a biased closed position occluding an inlet. When released, the inlet valve head undergoes a single oscillation past the equilibrium position to a maximum open position and returns to a biased return position close to the closed position to choke the flow and produce a pressure drop across the inlet valve causing the inlet valve to close. In other embodiments, the harmonic oscillator arrangement of the inlet valve enables the uniflow engine to be reversibly operated as a uniflow compressor.
International Nuclear Information System (INIS)
Au, R.; Fowler, M.; Hanawa, H.; Riedel, J.; Qua, Z.G.
1984-01-01
In early 1983 it was decided to mount coils on arms separated by 120 degrees and buck them out so that the third harmonic dphi/dt component would be cancelled and thus the first and second field harmonics could be very accurately measured. The original intention was to do as others had done, namely, use fast ADC's to read the voltages, and computer process the result to get the Fourier components. However, because of the 100 to 1 dynamic range of the fast ADC's and the likelihood that noise would be a problem, the authors decided to do things differently. Using a fast Fourier transform analyzer was considered, but this instrument is very expensive, so they decided to use a completely electronic analog approach: The authors decided to use active bandpass filters to render the harmonic components
Frequency chirp of harmonic and attosecond pulses
International Nuclear Information System (INIS)
Varju, K.; Johansson, P; L'Huillier, A.L.; Mairesse, Y.; Salieres, P.
2005-01-01
Full text: We have explored in detail the first- and second-order variations of the atomic phase as a function of the laser intensity and harmonic order. This unravels the similitudes and differences existing between the chirp of individual harmonic pulses and the chirp of the attosecond pulses. We show that the two techniques XFROG and RABITT used to characterize the two chirps (respectively) converge to give the same information, namely the values of the mixed partial derivatives of the atomic phase. This underlines the common physical origin of all these phenomena and provides a unified frame for their description and understanding. Ref. 1 (author)
Harmonic arbitrary waveform generator
Roberts, Brock Franklin
2017-11-28
High frequency arbitrary waveforms have applications in radar, communications, medical imaging, therapy, electronic warfare, and charged particle acceleration and control. State of the art arbitrary waveform generators are limited in the frequency they can operate by the speed of the Digital to Analog converters that directly create their arbitrary waveforms. The architecture of the Harmonic Arbitrary Waveform Generator allows the phase and amplitude of the high frequency content of waveforms to be controlled without taxing the Digital to Analog converters that control them. The Harmonic Arbitrary Waveform Generator converts a high frequency input, into a precision, adjustable, high frequency arbitrary waveform.
General Criterion for Harmonicity
Proesmans, Karel; Vandebroek, Hans; Van den Broeck, Christian
2017-10-01
Inspired by Kubo-Anderson Markov processes, we introduce a new class of transfer matrices whose largest eigenvalue is determined by a simple explicit algebraic equation. Applications include the free energy calculation for various equilibrium systems and a general criterion for perfect harmonicity, i.e., a free energy that is exactly quadratic in the external field. As an illustration, we construct a "perfect spring," namely, a polymer with non-Gaussian, exponentially distributed subunits which, nevertheless, remains harmonic until it is fully stretched. This surprising discovery is confirmed by Monte Carlo and Langevin simulations.
Harmonic Analyzing of the Double PWM Converter in DFIG Based on Mathematical Model
Directory of Open Access Journals (Sweden)
Jing Liu
2017-12-01
Full Text Available Harmonic pollution of double fed induction generators (DFIGs has become a vital concern for its undesirable effects on power quality issues of wind generation systems and grid-connected system, and the double pulse width modulation (PWMconverter is one of the main harmonic sources in DFIGs. Thus the harmonic analysis of the converter in DFIGs is a necessary step to evaluate their harmonic pollution of DFIGs. This paper proposes a detailed harmonic modeling method to discuss the main harmonic components in a converter. In general the harmonic modeling could be divided into the low-order harmonic part (up to 30th order and the high-order harmonic part (greater than order 30 parts in general. The low-order harmonics are produced by the circuit topology and control algorithm, and the harmonic component will be different if the control strategy changes. The high-order harmonics are produced by the modulation of the switching function to the dc variable. In this paper, the low-order harmonic modeling is established according to the directions of power flow under the vector control (VC, and the high-order harmonic modeling is established by the switching function of space vector PWM and dc currents. Meanwhile, the simulations of harmonic a components in a converter are accomplished in a real time digital simulation system. The results indicate that the proposed modeling could effectively show the harmonics distribution of the converter in DFIGs.
Harmonic Maass forms and mock modular forms
Bringmann, Kathrin; Ono, Ken
2017-01-01
Modular forms and Jacobi forms play a central role in many areas of mathematics. Over the last 10-15 years, this theory has been extended to certain non-holomorphic functions, the so-called "harmonic Maass forms". The first glimpses of this theory appeared in Ramanujan's enigmatic last letter to G. H. Hardy written from his deathbed. Ramanujan discovered functions he called "mock theta functions" which over eighty years later were recognized as pieces of harmonic Maass forms. This book contains the essential features of the theory of harmonic Maass forms and mock modular forms, together with a wide variety of applications to algebraic number theory, combinatorics, elliptic curves, mathematical physics, quantum modular forms, and representation theory.
Cost and performance analysis of physical security systems
International Nuclear Information System (INIS)
Hicks, M.J.; Yates, D.; Jago, W.H.; Phillips, A.W.
1998-04-01
Analysis of cost and performance of physical security systems can be a complex, multi-dimensional problem. There are a number of point tools that address various aspects of cost and performance analysis. Increased interest in cost tradeoffs of physical security alternatives has motivated development of an architecture called Cost and Performance Analysis (CPA), which takes a top-down approach to aligning cost and performance metrics. CPA incorporates results generated by existing physical security system performance analysis tools, and utilizes an existing cost analysis tool. The objective of this architecture is to offer comprehensive visualization of complex data to security analysts and decision-makers
Omega-Harmonic Functions and Inverse Conductivity Problems on Networks
National Research Council Canada - National Science Library
Berenstein, Carlos A; Chung, Soon-Yeong
2003-01-01
.... To do this, they introduce an elliptic operator DELTA omega and an omega-harmonic function on the graph, with its physical interpretation being the diffusion equation on the graph, which models an electric network...
Harmonics in large offshore wind farms
DEFF Research Database (Denmark)
Kocewiak, Lukasz Hubert
and nature of various harmonic components. A comprehensive comparison of harmonic voltages and currents based on probability distribution estimation and appropriate statistics calculation (mean, variance, probability density function, etc.) is applied. Such approach gives a better overview and comparison...... and analysis, and ϐinally ending up on modelling and models application. Different aspects of validation in time domain, frequency domain, and by application of statistical methods are mentioned in relation to respective problems. Measurements constitute a core part in industry-oriented research. Due...... that it is of great importance to know the nature of generated harmonics in large offshore wind farms in order to apply the most suitable data processing technique. Time-frequency analysis based on multiresolution wavelet transform is used in order to perform time-frequency domain analysis helpful to distinguish...
Improving the voltage quality of an inverter via by-passing the harmonic current components
DEFF Research Database (Denmark)
Zhong, Qing-Chang; Blaabjerg, Frede; Guerrero, Josep M.
2012-01-01
In this paper, a control strategy is proposed to improve the total harmonic distortion (THD) of the output voltage of an inverter. The physical interpretation of the control strategy is to connect shunt resonant filters at harmonic frequencies to the output so that the harmonic current components...
Comparing Harmonic Similarity Measures
de Haas, W.B.; Robine, M.; Hanna, P.; Veltkamp, R.C.; Wiering, F.
2010-01-01
We present an overview of the most recent developments in polyphonic music retrieval and an experiment in which we compare two harmonic similarity measures. In contrast to earlier work, in this paper we specifically focus on the symbolic chord description as the primary musical representation and
DEFF Research Database (Denmark)
Nielsen, Jesper Kjær; Jensen, Tobias Lindstrøm; Jensen, Jesper Rindom
2017-01-01
-robust to noise, or very computationally inten- sive. In this paper, we propose a fast algorithm for the harmonic chirp summation method which has been demonstrated in the liter- ature to be accurate and robust to noise. The proposed algorithm is orders of magnitudes faster than previous algorithms which is also...
Harmonically excited orbital variations
International Nuclear Information System (INIS)
Morgan, T.
1985-01-01
Rephrasing the equations of motion for orbital maneuvers in terms of Lagrangian generalized coordinates instead of Newtonian rectangular cartesian coordinates can make certain harmonic terms in the orbital angular momentum vector more readily apparent. In this formulation the equations of motion adopt the form of a damped harmonic oscillator when torques are applied to the orbit in a variationally prescribed manner. The frequencies of the oscillator equation are in some ways unexpected but can nonetheless be exploited through resonant forcing functions to achieve large secular variations in the orbital elements. Two cases are discussed using a circular orbit as the control case: (1) large changes in orbital inclination achieved by harmonic excitation rather than one impulsive velocity change, and (2) periodic and secular changes to the longitude of the ascending node using both stable and unstable excitation strategies. The implications of these equations are also discussed for both artificial satellites and natural satellites. For the former, two utilitarian orbits are suggested, each exploiting a form of harmonic excitation. 5 refs
Pruitt, Kathryn Ringler
2012-01-01
This dissertation proposes a model of word stress in a derivational version of Optimality Theory (OT) called Harmonic Serialism (HS; Prince and Smolensky 1993/2004, McCarthy 2000, 2006, 2010a). In this model, the metrical structure of a word is derived through a series of optimizations in which the "best" metrical foot is chosen…
Gluck, P.; Krakower, Zeev
2010-01-01
We present a unit comprising theory, simulation and experiment for a body oscillating on a vertical spring, in which the simultaneous use of a force probe and an ultrasonic range finder enables one to explore quantitatively and understand many aspects of simple and damped harmonic motions. (Contains 14 figures.)
HTR core physics analysis at NRG
International Nuclear Information System (INIS)
Kuijper, J.C.; Haas, J.B.M. de; Oppe, J.
2002-01-01
Since a number of years NRG is developing the HTR reactor physics code system PANTHERMIX. In PANTHERMIX the 3-D steady-state and transient core physics code PANTHER has been interfaced with the HTR thermal hydraulics code THERMIX to enable core follow and transient analyses on both pebble bed and block type HTR systems. Recently the capabilities of PANTHERMIX have been extended with the possibility to simulate the flow of pebbles through the core cavity and the (re)loading of pebbles on top of the core.The PANTHERMIX code system is being applied for the benchmark exercises for the Chinese HTR-10 and Japanese HTTR first criticality, calculating the critical loading, control rod worth and the isothermal temperature coefficients at zero power conditions. Also core physics calculations have been performed on an early version the South African PBMR design. The reactor physics properties of the reactor at equilibrium core loading have been studied as well as a selected run-in scenario, starting form fresh fuel. The recently developed reload option of PANTHERMIX was used extensively in these analyses. The examples shown demonstrate the capabilities of PANTHERMIX for performing steady-state and transient HTR core physics analyses. However, additional validation, especially for transient analyses, remains desirable. (author)
The physics analysis tools project for the ATLAS experiment
International Nuclear Information System (INIS)
Lenzi, Bruno
2012-01-01
The Large Hadron Collider is expected to start colliding proton beams in 2009. The enormous amount of data produced by the ATLAS experiment (≅1 PB per year) will be used in searches for the Higgs boson and Physics beyond the standard model. In order to meet this challenge, a suite of common Physics Analysis Tools has been developed as part of the Physics Analysis software project. These tools run within the ATLAS software framework, ATHENA, covering a wide range of applications. There are tools responsible for event selection based on analysed data and detector quality information, tools responsible for specific physics analysis operations including data quality monitoring and physics validation, and complete analysis tool-kits (frameworks) with the goal to aid the physicist to perform his analysis hiding the details of the ATHENA framework. (authors)
An SQL-based approach to physics analysis
International Nuclear Information System (INIS)
Limper, Dr Maaike
2014-01-01
As part of the CERN openlab collaboration a study was made into the possibility of performing analysis of the data collected by the experiments at the Large Hadron Collider (LHC) through SQL-queries on data stored in a relational database. Currently LHC physics analysis is done using data stored in centrally produced 'ROOT-ntuple' files that are distributed through the LHC computing grid. The SQL-based approach to LHC physics analysis presented in this paper allows calculations in the analysis to be done at the database and can make use of the database's in-built parallelism features. Using this approach it was possible to reproduce results for several physics analysis benchmarks. The study shows the capability of the database to handle complex analysis tasks but also illustrates the limits of using row-based storage for storing physics analysis data, as performance was limited by the I/O read speed of the system.
Young children's harmonic perception.
Costa-Giomi, Eugenia
2003-11-01
Harmony and tonality are two of the most difficult elements for young children to perceive and manipulate and are seldom taught in the schools until the end of early childhood. Children's gradual harmonic and tonal development has been attributed to their cumulative exposure to Western tonal music and their increasing experiential knowledge of its rules and principles. Two questions that are relevant to this problem are: (1) Can focused and systematic teaching accelerate the learning of the harmonic/tonal principles that seem to occur in an implicit way throughout childhood? (2) Are there cognitive constraints that make it difficult for young children to perceive and/or manipulate certain harmonic and tonal principles? A series of studies specifically addressed the first question and suggested some possible answers to the second one. Results showed that harmonic instruction has limited effects on children's perception of harmony and indicated that the drastic improvement in the perception of implied harmony noted approximately at age 9 is due to development rather than instruction. I propose that young children's difficulty in perceiving implied harmony stems from their attention behaviors. Older children have less memory constraints and more strategies to direct their attention to the relevant cues of the stimulus. Younger children focus their attention on the melody, if present in the stimulus, and specifically on its concrete elements such as rhythm, pitch, and contour rather than its abstract elements such as harmony and key. The inference of the abstract harmonic organization of a melody required in the perception of implied harmony is thus an elusive task for the young child.
Gradient formula for the four-dimensional hyperspherical harmonics
International Nuclear Information System (INIS)
Santos, M.B.
1975-01-01
The gradient formula for the hyperspherical harmonics in 4 dimensions is derived, a result which is here obtainned in two distinct ways: either by differentiation of a closed expression for the hyperspherical harmonics or by making use of the Wigner-Eckart theorem for the R 4 group. The result is useful for physical applications in view of the significance of the R 4 group in several physical problems [pt
International Nuclear Information System (INIS)
Meilleurat, Michele
1973-07-01
The application of harmonic analysis to the brain spontaneous electrical activity has been studied theoretically and practically in 30 adult rabbits chronically implanted with electrodes. Theoretically, an accurate energetic study of the signal can only be achieved by the calculation of the autocorrelation function and its Fourier transform, the power density spectrum. Secondly, a comparative study has been made of the analogical methods using analogic or hybrid devices and the digital method with an analysis and computing program (the sampling rate, the delay, the period of integration and the problems raised by the amplification of the biological signals and sampling). Data handling is discussed, the method mainly retaining the study of variance, the calculation of the total energy carried by the signal and the energies carried along the frequency bandwidth ΔF, their percentage as related to the total energy, the relationships of these various values for various electroencephalographic states. Experimentally, the general aspect of the spontaneous electric activity of the dorsal hippocampus and the visual cortex during vigilance variations is accurately described by the calculation of the variance and the study of the position of the maximum values of the peaks of the power density spectra on the frequency axis as well as by the calculation of the energies carried in various frequency bands, 0-4, 4-8, 8-12 Hz. With the same theoretical bases, both the analogical and digital methods lead to similar results, the former being easier to operate, the latter more accurate. (author) [fr
Harmonic Patterns in Forex Trading
Nemček, Sebastian
2013-01-01
This diploma thesis is committed to examination of validity of Harmonic Patterns in Forex trading. Scott Carney described existing and introduced new Harmonic Patterns in 1999 in his book Harmonic Trader. These patterns use the Fibonacci principle to analyze price action and to provide both bullish and bearish trading signals. The goal of this thesis is to find out whether harmonic trading strategy on selected pairs is profitable in FX market, which patterns are the most profitable and what i...
TOTEM Physics program, analysis and results
CERN. Geneva
2013-01-01
The published results will be quickly reviewed. The current analyses of the data taken in the joint TOTEM-CMS runs will be discussed, including forward multiplicities, jets physics, soft diffractive processes, and related cross-sections. Progress in the study of low-t elastic scattering will be presented.
Physical Analysis of an Electric Resistor Heating
Perea Martins, J. E. M.
2018-01-01
This work describes a simple experiment to measure the resistor temperature as a function of the applied power and proves that it is an efficient way to introduce some important physical concepts in classroom, including the Joule's first law, hot-spot temperature, thermal resistance, thermal dissipation constant, time constant and the Newton's law…
Physical analysis of an electric resistor heating
Perea Martins, J. E. M.
2018-05-01
This work describes a simple experiment to measure the resistor temperature as a function of the applied power and proves that it is an efficient way to introduce some important physical concepts in classroom, including the Joule’s first law, hot-spot temperature, thermal resistance, thermal dissipation constant, time constant and the Newton’s law of cooling.
Coherent harmonic production using a two-section undulator FEL
Energy Technology Data Exchange (ETDEWEB)
Jaroszynski, D.A. [Commissariat a l`Energie, Bruyeres-le-Chatel (France); Prazeres, R.; Glotin, F. [Centre Universitaire Paris-Sud (France)] [and others
1995-12-31
We present measurements and a theoretical analysis of a new method of generating harmonic radiation in a free-electron laser oscillator with a two section undulator in a single optical cavity. To produce coherent harmonic radiation the undulator is arranged so that the downstream undulator section resonance frequency matches a harmonic of the upstream undulator. Both the fundamental and the harmonic optical fields evolve in the same optical cavity and are coupled out with different extraction fractions using a hole in one of the cavity mirrors. We present measurements that show that the optical power at the second and third harmonic can be enhanced by more than an order of magnitude in this fundamental/harmonic configuration. We compare the production of harmonic radiation of a two sectioned fundamental/harmonic undulator with that produced from a FEL operating at its highest efficiency with a step-tapered undulator, where the bunching at the end of the first section is very large. We examine, the dependence of the harmonic power on the intracavity power by adjusting the optical cavity desynchronism, {delta}L. We also examine the evolution of the fundamental and harmonic powers as a function of cavity roundtrip number to evaluate the importance of the small signal gain at the harmonic. We compare our measurements with predictions of a multi-electron numerical model that follows the evolution of fundamental and harmonic power to saturation. This fundamental/harmonic mode, of operation of the FEL may have useful applications in the production of coherent X-ray and VUV radiation, a spectral range where high reflectivity optical cavity mirrors are difficult or impossible to manufacture.
Atto second high harmonic sources
International Nuclear Information System (INIS)
Nam, Chang Hee
2008-01-01
High harmonic generation is a powerful method to produce attosecond pulses. The high harmonics, emitted from atoms driven by intense femtosecond laser pulses, can from an attosecond pulse train with equally spaced harmonic spectrum or an isolated single attosecond pulse with broad continuum spectrum. Using high power femtosecond laser technology developed at CXRC, we have investigated the spectral and temporal characteristics of high harmonics obtained from gaseous atoms. The spectral structure of harmonics could be manipulated by controlling laser chirp, and continuous tuning of harmonic wavelengths was achieved. For rigorous temporal characterization of attosecond harmonic pulses a cross correlation technique was applied to the photoionization process by harmonic and IR femtosecond pulses and achieved the complete temporal reconstruction of attosecond pulse trains, revealing the detailed temporal structure of the attosecond chirp by material dispersion. The duration of attosecond high harmonic pulses is usually much longer than that of transform limited pulses due to the inherent chirp originating from the harmonic generation process. The attosecond chirp compensation in the harmonic generation medium itself was demonstrated, thereby realizing the generation of near transform limited attosecond pulses. The interference of attosecond electron wave packets, generated from an atom by attosecond harmonic pulses, will be also presented
Second harmonic inversion for ultrasound contrast harmonic imaging
Energy Technology Data Exchange (ETDEWEB)
Pasovic, Mirza; Danilouchkine, Mike; Faez, Telli; Van Neer, Paul L M J; Van der Steen, Antonius F W; De Jong, Nico [THORAXCENTER, Department of Biomedical Engineering Ee2302, Erasmus MC, Rotterdam (Netherlands); Cachard, Christian; Basset, Olivier, E-mail: mirza.pasovic@creatis.insa-lyon.fr [CREATIS-LRMN, Universite de Lyon, INSA-Lyon, Universite Lyon 1, Inserm U630, CNRS UMR 5220 (France)
2011-06-07
Ultrasound contrast agents (UCAs) are small micro-bubbles that behave nonlinearly when exposed to an ultrasound wave. This nonlinear behavior can be observed through the generated higher harmonics in a back-scattered echo. In past years several techniques have been proposed to detect or image harmonics produced by UCAs. In these proposed works, the harmonics generated in the medium during the propagation of the ultrasound wave played an important role, since these harmonics compete with the harmonics generated by the micro-bubbles. We present a method for the reduction of the second harmonic generated during nonlinear-propagation-dubbed second harmonic inversion (SHI). A general expression for the suppression signals is also derived. The SHI technique uses two pulses, p' and p'', of the same frequency f{sub 0} and the same amplitude P{sub 0} to cancel out the second harmonic generated by nonlinearities of the medium. Simulations show that the second harmonic is reduced by 40 dB on a large axial range. Experimental SHI B-mode images, from a tissue-mimicking phantom and UCAs, show an improvement in the agent-to-tissue ratio (ATR) of 20 dB compared to standard second harmonic imaging and 13 dB of improvement in harmonic power Doppler.
Second harmonic inversion for ultrasound contrast harmonic imaging
International Nuclear Information System (INIS)
Pasovic, Mirza; Danilouchkine, Mike; Faez, Telli; Van Neer, Paul L M J; Van der Steen, Antonius F W; De Jong, Nico; Cachard, Christian; Basset, Olivier
2011-01-01
Ultrasound contrast agents (UCAs) are small micro-bubbles that behave nonlinearly when exposed to an ultrasound wave. This nonlinear behavior can be observed through the generated higher harmonics in a back-scattered echo. In past years several techniques have been proposed to detect or image harmonics produced by UCAs. In these proposed works, the harmonics generated in the medium during the propagation of the ultrasound wave played an important role, since these harmonics compete with the harmonics generated by the micro-bubbles. We present a method for the reduction of the second harmonic generated during nonlinear-propagation-dubbed second harmonic inversion (SHI). A general expression for the suppression signals is also derived. The SHI technique uses two pulses, p' and p'', of the same frequency f 0 and the same amplitude P 0 to cancel out the second harmonic generated by nonlinearities of the medium. Simulations show that the second harmonic is reduced by 40 dB on a large axial range. Experimental SHI B-mode images, from a tissue-mimicking phantom and UCAs, show an improvement in the agent-to-tissue ratio (ATR) of 20 dB compared to standard second harmonic imaging and 13 dB of improvement in harmonic power Doppler.
Nonlinear physical systems spectral analysis, stability and bifurcations
Kirillov, Oleg N
2013-01-01
Bringing together 18 chapters written by leading experts in dynamical systems, operator theory, partial differential equations, and solid and fluid mechanics, this book presents state-of-the-art approaches to a wide spectrum of new and challenging stability problems.Nonlinear Physical Systems: Spectral Analysis, Stability and Bifurcations focuses on problems of spectral analysis, stability and bifurcations arising in the nonlinear partial differential equations of modern physics. Bifurcations and stability of solitary waves, geometrical optics stability analysis in hydro- and magnetohydrodynam
Shah, Lisa; Hao, Jie; Rodriguez, Christian A.; Fallin, Rebekah; Linenberger-Cortes, Kimberly; Ray, Herman E.; Rushton, Gregory T.
2018-06-01
A generally agreed upon tenant of the physics teaching community is the centrality of subject-specific expertise in effective teaching. However, studies which assess the content knowledge of incoming K-12 physics teachers in the U.S. have not yet been reported. Similarly lacking are studies on if or how the demographic makeup of aspiring physics educators is different from previously reported analyses of the actual high school physics teaching workforce. Here we present findings about the demographics and subject knowledge of prospective high school physics teachers using data from Praxis physics subject assessments administered between 2006 and 2016. Our analysis reveals significant variations in exam participation and performance between men and women, as well as those with different undergraduate majors and academic performance over the past decade. Findings from this work inform understandings and decisions about the quality, recruitment, and preparation of the high school physics teaching workforce.
Physics and Analysis at a Hadron Collider - Searching for New Physics (2/3)
CERN. Geneva
2010-01-01
This is the second lecture of three which together discuss the physics of hadron colliders with an emphasis on experimental techniques used for data analysis. This second lecture discusses techniques important for analyses searching for new physics using the CDF B_s --> mu+ mu- search as a specific example. The lectures are aimed at graduate students.
McEvilly, Nollaig; Verheul, Martine; Atencio, Matthew; Jess, Mike
2014-01-01
This paper provides an analysis of the discourses associated with physical education in Scotland's "Curriculum for Excellence". We implement a poststructural perspective in order to identify the discourses that underpin the physical education sections of the "Curriculum for Excellence" "health and well-being"…
International Nuclear Information System (INIS)
Sarkar, P.; Bhattacharyya, S.P.
1995-01-01
The effects of quartic anharmonicity on the quantum dynamics of a linear oscillator with time-dependent force constant (K) or harmonic frequency (ω) are studied both perturbatively and numerically by the time-dependent Fourier grid Hamiltonian method. In the absence of anharmonicity, the ground-state population decreases and the population of an accessible excited state (k = 2.4, 6 ... ) increases with time. However, when anharmonicity is introduced, both the ground- and excited-state populations show typical oscillations. For weak coupling, the population of an accessible excited state at a certain instant of time (short) turns out to be a parabolic function of the anharmonic coupling constant (λ), when all other parameters of the system are kept fixed. This parabolic nature of the excited-state population vs. the λ profile is independent of the specific form of the time dependence of the force constant, K t . However, it depends upon the rate at which K t relaxes. For small anharmonic coupling strength and short time scales, the numerical results corroborate expectations based on the first-order time-dependent perturbative analysis, using a suitably repartitioned Hamiltonian that makes H 0 time-independent. Some of the possible experimental implications of our observations are analyzed, especially in relation to intensity oscillations observed in some charge-transfer spectra in systems in which the dephasing rates are comparable with the time scale of the electron transfer. 21 refs., 7 figs., 1 tab
Compatibility analysis of DUPIC fuel (part 3) - radiation physics analysis
International Nuclear Information System (INIS)
Kim, Chun Soo; Bae, Dae Seok; Kim, Kyung Su; Park, Byung Yun; Koh, Young Kown
2000-04-01
As a part of the compatibility analysis of DUPIC fuel in CANDU reactors, the radiation physics calculations have been performed for the CANDU primary shielding system, thermal shield, radiation damage, transportation cask and storage. At first, the primary shield system was assessed for the DUPIC fuel core, which has shown that the dose rates and heat deposition rates through the primary shield of the DUPIC fuel core are not much different from those of natural uranium core because the power levels on the core periphery are similar for both cores. Secondly, the radiation effects on the critical components and the themal shields were assessed when the DUPIC fuel is loaded in CANDU reactors. Compared with the displacement per atom (DPA) of the critical component for natural uranium core, that for the DUPIC fuel core was increased by -30% for the innermost groove and the weld points and by -10% for the corner of the calandria subshells and annular plates in the calandria, respectivdely. Finally, the feasibility study of the DUPIC fuel handling was performed, which has shown that all handling and inspection of the DUPIC fuel bundles be done remotely and behind a shielding wall. For the transportation of the DUPIC fuel, the preliminary study has shown that there shold be no technical problem th design a transportation cask for the fresh and spent DUPIC fuel bundles. For the storage of the fresh and spent DUPIC fuels, there is no the criticality safety problem unless the fuel bundle geometry is destroyed
Compatibility analysis of DUPIC fuel (part 3) - radiation physics analysis
Energy Technology Data Exchange (ETDEWEB)
Kim, Chun Soo; Bae, Dae Seok; Kim, Kyung Su; Park, Byung Yun; Koh, Young Kown
2000-04-01
As a part of the compatibility analysis of DUPIC fuel in CANDU reactors, the radiation physics calculations have been performed for the CANDU primary shielding system, thermal shield, radiation damage, transportation cask and storage. At first, the primary shield system was assessed for the DUPIC fuel core, which has shown that the dose rates and heat deposition rates through the primary shield of the DUPIC fuel core are not much different from those of natural uranium core because the power levels on the core periphery are similar for both cores. Secondly, the radiation effects on the critical components and the themal shields were assessed when the DUPIC fuel is loaded in CANDU reactors. Compared with the displacement per atom (DPA) of the critical component for natural uranium core, that for the DUPIC fuel core was increased by -30% for the innermost groove and the weld points and by -10% for the corner of the calandria subshells and annular plates in the calandria, respectivdely. Finally, the feasibility study of the DUPIC fuel handling was performed, which has shown that all handling and inspection of the DUPIC fuel bundles be done remotely and behind a shielding wall. For the transportation of the DUPIC fuel, the preliminary study has shown that there shold be no technical problem th design a transportation cask for the fresh and spent DUPIC fuel bundles. For the storage of the fresh and spent DUPIC fuels, there is no the criticality safety problem unless the fuel bundle geometry is destroyed.
More physics in the laundromat
Denny, Mark
2010-12-01
The physics of a washing machine spin cycle is extended to include the spin-up and spin-down phases. We show that, for realistic parameters, an adiabatic approximation applies, and thus the familiar forced, damped harmonic oscillator analysis can be applied to these phases.
Core physics calculation and analysis for SNRE
International Nuclear Information System (INIS)
Xie Jiachun; Zhao Shouzhi; Jia Baoshan
2010-01-01
Five different precise calculation models have been set up for Small Nuclear Rocket Engine (SNRE) core based on MCNP code, and then the effective multiplication constant, drum control worth and power distribution were calculated. The results from different models indicate that the model in which elements are homogeneous could be used in the reactivity calculation, but a detailed description of elements have to be used in the element internal power distribution calculation. The results of physics parameters show that the basic characteristics of SNRE are reasonable. The drum control worth is sufficient. The power distribution is symmetrical and reasonable. All of the parameters can satisfy the design requirement. (authors)
Gorlow, Stanislaw; Ramona, Mathieu; Pachet, François
2016-01-01
Jazz guitar solos are improvised melody lines played on one instrument on top of a chordal accompaniment (comping). As the improvisation happens spontaneously, a reference score is non-existent, only a lead sheet. There are situations, however, when one would like to have the original melody lines in the form of notated music, see the Real Book. The motivation is either for the purpose of practice and imitation or for musical analysis. In this work, an automatic transcriber for jazz guitar so...
[Harmonization of TSH Measurements.
Takeoka, Keiko; Hidaka, Yoh; Hishinuma, Akira; Ikeda, Katsuyoshi; Okubo, Shigeo; Tsuchiya, Tatsuyuki; Hashiguchi, Teruto; Furuta, Koh; Hotta, Taeko; Matsushita, Kazuyuki; Matsumoto, Hiroyuki; Murakami, Masami; Maekawa, Masato
2016-05-01
The measured concentration of thyroid stimulating hormone (TSH) differs depending on the reagents used. Harmonization of TSH is crucial because the decision limits are described in current clinical practice guide- lines as absolute values, e.g. 2.5 mIU/L in early pregnancy. In this study, we tried to harmonize the report- ed concentrations of TSH using the all-procedure trimmed mean. TSH was measured in 146 serum samples, with values ranging from 0.01 to 18.8 mIU/L, using 4 immunoassays. The concentration of TSH was highest with E test TOSOH and lowest with LUMIPULSE. The concentrations with each reagent were recalculated with the following formulas: E test TOSOH 0.855x-0.014; ECLusys 0.993x+0.079; ARCHITECT 1.041x- 0.010; and LUMIPULSE 1.096x-0.015. Recalculation eliminated the between-assay discrepancy. These formulas may be used until harmonization of TSH is achieved by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC).
Effect of Frequency and Spatial-Harmonics on Rotary and Linear Induction Motor Characteristics
1972-03-01
A computer analysis is made of the effect of current and MMF airgap harmonics on the output characteristics of rotary and linear induction motors. The current harmonics accompanying thyristor-control operation are evaluated by Fourier analyzing the p...
Physical activity and physical self-concept in youth: systematic review and meta-analysis.
Babic, Mark J; Morgan, Philip J; Plotnikoff, Ronald C; Lonsdale, Chris; White, Rhiannon L; Lubans, David R
2014-11-01
Evidence suggests that physical self-concept is associated with physical activity in children and adolescents, but no systematic review of this literature has been conducted. The primary aim of this systematic review and meta-analysis was to determine the strength of associations between physical activity and physical self-concept (general and sub-domains) in children and adolescents. The secondary aim was to examine potential moderators of the association between physical activity and physical self-concept. A systematic search of six electronic databases (MEDLINE, CINAHL, SPORTDiscus, ERIC, Web of Science and Scopus) with no date restrictions was conducted. Random effects meta-analyses with correction for measurement were employed. The associations between physical activity and general physical self-concept and sub-domains were explored. A risk of bias assessment was conducted by two reviewers. The search identified 64 studies to be included in the meta-analysis. Thirty-three studies addressed multiple outcomes of general physical self-concept: 28 studies examined general physical self-concept, 59 examined perceived competence, 25 examined perceived fitness, and 55 examined perceived appearance. Perceived competence was most strongly associated with physical activity (r = 0.30, 95% CI 0.24-0.35, p self-concept (r = 0.25, 95% CI 0.16-0.34, p self-concept (p self-concept and its various sub-domains in children and adolescents. Age and sex are key moderators of the association between physical activity and physical self-concept.
P. Sphicas
The CPT project came to an end in December 2006 and its original scope is now shared among three new areas, namely Computing, Offline and Physics. In the physics area the basic change with respect to the previous system (where the PRS groups were charged with detector and physics object reconstruction and physics analysis) was the split of the detector PRS groups (the old ECAL-egamma, HCAL-jetMET, Tracker-btau and Muons) into two groups each: a Detector Performance Group (DPG) and a Physics Object Group. The DPGs are now led by the Commissioning and Run Coordinator deputy (Darin Acosta) and will appear in the correspond¬ing column in CMS bulletins. On the physics side, the physics object groups are charged with the reconstruction of physics objects, the tuning of the simulation (in collaboration with the DPGs) to reproduce the data, the provision of code for the High-Level Trigger, the optimization of the algorithms involved for the different physics analyses (in collaboration with the analysis gr...
Physical Readiness Training: A Meta-Analysis
National Research Council Canada - National Science Library
Vickers, Jr, Ross R
2007-01-01
.... This meta-analysis of available PRT studies (k = 3) indicated that (a) Fitness gains in the PRT program were equal to the gains in traditional fitness programs, and (b) the injury rate (i.e., hazard ratio...
Variation of Rainfall in Three Nigerian Stations, Using harmonic ...
African Journals Online (AJOL)
This work is on the variation of rainfall using harmonic analysis for Portharcourt, Kano and Makurdi data, for the three stations the period of study covered 1977 to 2010, for which the time series plot, the amplitude, the first, second and third harmonics were generated. Portharcourt has a gently increasing trend with ...
D. Acosta
2010-01-01
A remarkable amount of progress has been made in Physics since the last CMS Week in June given the exponential growth in the delivered LHC luminosity. The first major milestone was the delivery of a variety of results to the ICHEP international conference held in Paris this July. For this conference, CMS prepared 15 Physics Analysis Summaries on physics objects and 22 Summaries on new and interesting physics measurements that exploited the luminosity recorded by the CMS detector. The challenge was incorporating the largest batch of luminosity that was delivered only days before the conference (300 nb-1 total). The physics covered from this initial running period spanned hadron production measurements, jet production and properties, electroweak vector boson production, and even glimpses of the top quark. Since then, the accumulated integrated luminosity has increased by a factor of more than 100, and all groups have been working tremendously hard on analysing this dataset. The September Physics Week was held ...
Music of the heavens Kepler's harmonic astronomy
Stephenson, Bruce
2014-01-01
Valued today for its development of the third law of planetary motion, Harmonice mundi (1619) was intended by Kepler to expand on ancient efforts to discern a Creator's plan for the planetary system--an arrangement thought to be based on harmonic relationships. Challenging critics who characterize Kepler's theories of harmonic astronomy as ""mystical,"" Bruce Stephenson offers the first thorough technical analysis of the music the astronomer thought the heavens made, and the logic that led him to find musical patterns in his data. In so doing, Stephenson illuminates crucial aspects of Kepler'
DIII-D physics analysis database
International Nuclear Information System (INIS)
Bramson, G.; Schissel, D.P.; DeBoo, J.C.; St John, H.
1990-10-01
Since June 1986 the DIII-D tokamak has had over 16000 discharges accumulating more than 250 Gigabytes of raw data (currently over 30 Mbytes per discharge). The centralized DIII-D databases and the associated support software described earlier provide the means to extract, analyze, store, and display reduced sets of data for specific physics issues. The confinement, stability, transition, and cleanliness databases consist of more than 7500 records of basic reduced diagnostic data datasets. Each database record corresponds to a specific snapshot in time for a selected discharge. Recently some profile datasets have been implemented. Diagnostic data are fit by a cubic spline or a parabola by the in-house ENERGY code to provide density, temperature, radiated power, effective charge (Z eff ), and rotation velocity profiles. These fits are stored in the profile datasets which are inputs for the ONETWO code which computes transport data. 3 refs., 4 figs
PHYSICAL ANALYSIS OF QUALITY WOOD Melia azedarach
Directory of Open Access Journals (Sweden)
T. J. da Silva
2016-07-01
Full Text Available Forest species, in general, present a slow growth, which results and profits can manifest themselves in the long run, it becomes necessary the study and discovery of new species that may provide raw materials and return on invested capital more immediate, being that the Melia azedarach wood is a potential option. In the absence of information about, the objective of this paper is to determine its physical properties: basic density and shrinkage of the Melia azedarach species in the Itapeva-SP region. The data obtained in this study allow to classify wood Melia azedarach as wood of average density and good dimensional stability. Feature that makes it ideal for its use in furniture industry. The low amount of research related to quality of this wood prevents the commercial use of it to achieve its full potential harnessing its effectively, and essential investments in this field.
Security analysis of cyber-physical system
Li, Bo; Zhang, Lichen
2017-05-01
In recent years, Cyber-Physical System (CPS) has become an important research direction of academic circles and scientific and technological circles at home and abroad, is considered to be following the third wave of world information technology after the computer, the Internet. PS is a multi-dimensional, heterogeneous, deep integration of open systems, Involving the computer, communication, control and other disciplines of knowledge. As the various disciplines in the research theory and methods are significantly different, so the application of CPS has brought great challenges. This paper introduces the definition and characteristics of CPS, analyzes the current situation of CPS, analyzes the security threats faced by CPS, and gives the security solution for security threats. It also discusses CPS-specific security technology, to promote the healthy development of CPS in information security.
Arjunan, V; Rani, T; Santhanam, R; Mohan, S
2012-10-01
The FT-IR and FT-Raman spectra of H bond inner conformer of 2,3-epoxypropanol have been recorded in the regions 3700-400 and 3700-100 cm(-1), respectively. The spectra were interpreted in terms of fundamentals modes, combination and overtone bands. The normal coordinate analysis was carried out to confirm the precision of the assignments. The structure of the conformers H bond inner and H bond outer1 were optimised and the structural characteristics were determined by density functional theory (DFT) using B3LYP and MP2 methods with 6-31G** and 6-311++G** basis sets. The vibrational frequencies were calculated in all these methods and were compared with the experimental frequencies which yield good agreement between observed and calculated frequencies. The electronic properties HOMO and LUMO energies were measured by time-dependent TD-DFT approach. Copyright © 2012 Elsevier B.V. All rights reserved.
The uncertainty in physical measurements an introduction to data analysis in the physics laboratory
Fornasini, Paolo
2008-01-01
All measurements of physical quantities are affected by uncertainty. Understanding the origin of uncertainty, evaluating its extent and suitably taking it into account in data analysis is essential for assessing the degree of accuracy of phenomenological relationships and physical laws in both scientific research and technological applications. The Uncertainty in Physical Measurements: An Introduction to Data Analysis in the Physics Laboratory presents an introduction to uncertainty and to some of the most common procedures of data analysis. This book will serve the reader well by filling the gap between tutorial textbooks and highly specialized monographs. The book is divided into three parts. The first part is a phenomenological introduction to measurement and uncertainty: properties of instruments, different causes and corresponding expressions of uncertainty, histograms and distributions, and unified expression of uncertainty. The second part contains an introduction to probability theory, random variable...
Audibility of harmonics in periodic "white noise"
Duifhuis, H.
1973-01-01
The finding that spectrally suppressed high harmonics (n>16) in a periodic pulse are perceptible has been related [H. Duifhuis, J. Acoust. Soc. Amer. 48, 888–893 (1970); 49, 1155–1163 (1971)] to the ear's limited resolving power in peripheral frequency analysis. The limited frequency resolution
Gesture Analysis for Physics Education Researchers
Scherr, Rachel E.
2008-01-01
Systematic observations of student gestures can not only fill in gaps in students' verbal expressions, but can also offer valuable information about student ideas, including their source, their novelty to the speaker, and their construction in real time. This paper provides a review of the research in gesture analysis that is most relevant to…
Accelerator physics analysis with interactive tools
International Nuclear Information System (INIS)
Holt, J.A.; Michelotti, L.
1993-05-01
Work is in progress on interactive tools for linear and nonlinear accelerator design, analysis, and simulation using X-based graphics. The BEAMLINE and MXYZPTLK class libraries, were used with an X Windows graphics library to build a program for interactively editing lattices and studying their properties
Chemical Applications of Second Harmonic Rayleigh Scattering ...
Indian Academy of Sciences (India)
Chemical Applications of Second Harmonic Rayleigh Scattering Puspendu Kumar Das Department of Inorganic and Physical Chemistry Indian Institute of Science Bangalore 560012, India pkdas@ipc.iisc.ernet.in · Slide 2 · Slide 3 · Slide 4 · Slide 5 · Slide 6 · Slide 7 · Slide 8 · Slide 9 · Slide 10 · Slide 11 · Slide 12 · Slide 13.
Computational and Physical Analysis of Catalytic Compounds
Wu, Richard; Sohn, Jung Jae; Kyung, Richard
2015-03-01
Nanoparticles exhibit unique physical and chemical properties depending on their geometrical properties. For this reason, synthesis of nanoparticles with controlled shape and size is important to use their unique properties. Catalyst supports are usually made of high-surface-area porous oxides or carbon nanomaterials. These support materials stabilize metal catalysts against sintering at high reaction temperatures. Many studies have demonstrated large enhancements of catalytic behavior due to the role of the oxide-metal interface. In this paper, the catalyzing ability of supported nano metal oxides, such as silicon oxide and titanium oxide compounds as catalysts have been analyzed using computational chemistry method. Computational programs such as Gamess and Chemcraft has been used in an effort to compute the efficiencies of catalytic compounds, and bonding energy changes during the optimization convergence. The result illustrates how the metal oxides stabilize and the steps that it takes. The graph of the energy computation step(N) versus energy(kcal/mol) curve shows that the energy of the titania converges faster at the 7th iteration calculation, whereas the silica converges at the 9th iteration calculation.
Analysis of graphical representation among freshmen in undergraduate physics laboratory
Adam, A. S.; Anggrayni, S.; Kholiq, A.; Putri, N. P.; Suprapto, N.
2018-03-01
Physics concept understanding is the importance of the physics laboratory among freshmen in the undergraduate program. These include the ability to interpret the meaning of the graph to make an appropriate conclusion. This particular study analyses the graphical representation among freshmen in an undergraduate physics laboratory. This study uses empirical study with quantitative approach. The graphical representation covers 3 physics topics: velocity of sound, simple pendulum and spring system. The result of this study shows most of the freshmen (90% of the sample) make a graph based on the data from physics laboratory. It means the transferring process of raw data which illustrated in the table to physics graph can be categorised. Most of the Freshmen use the proportional principle of the variable in graph analysis. However, Freshmen can't make the graph in an appropriate variable to gain more information and can't analyse the graph to obtain the useful information from the slope.
Analysis of pre-service physics teacher skills designing simple physics experiments based technology
Susilawati; Huda, C.; Kurniawan, W.; Masturi; Khoiri, N.
2018-03-01
Pre-service physics teacher skill in designing simple experiment set is very important in adding understanding of student concept and practicing scientific skill in laboratory. This study describes the skills of physics students in designing simple experiments based technologicall. The experimental design stages include simple tool design and sensor modification. The research method used is descriptive method with the number of research samples 25 students and 5 variations of simple physics experimental design. Based on the results of interviews and observations obtained the results of pre-service physics teacher skill analysis in designing simple experimental physics charged technology is good. Based on observation result, pre-service physics teacher skill in designing simple experiment is good while modification and sensor application are still not good. This suggests that pre-service physics teacher still need a lot of practice and do experiments in designing physics experiments using sensor modifications. Based on the interview result, it is found that students have high enough motivation to perform laboratory activities actively and students have high curiosity to be skilled at making simple practicum tool for physics experiment.
Accelerator physics analysis with an integrated toolkit
International Nuclear Information System (INIS)
Holt, J.A.; Michelotti, L.; Satogata, T.
1992-08-01
Work is in progress on an integrated software toolkit for linear and nonlinear accelerator design, analysis, and simulation. As a first application, ''beamline'' and ''MXYZPTLK'' (differential algebra) class libraries, were used with an X Windows graphics library to build an user-friendly, interactive phase space tracker which, additionally, finds periodic orbits. This program was used to analyse a theoretical lattice which contains octupoles and decapoles to find the 20th order, stable and unstable periodic orbits and to explore the local phase space structure
Analysis of physical characteristics of vegetable oils
Energy Technology Data Exchange (ETDEWEB)
Piamba Tulcan, Oscar Edwin [Universidade Nacional da Colombia (UNAL), Bogota (Colombia). Fac. de Ingenieria; Universidade Federal Fluminense (PGMEC/UFF), Niteroi, RJ (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica], E-mail: oepiambat@unal.edu.co; Andrade, Danielle Oliveira de; Andrade, Ednilton Tavares de [Universidade Federal Fluminense (TER/UFF), Niteroi, RJ (Brazil). Dept. de Engenharia Agricola e do Meio Ambiente; Pereira, Roberto Guimaraes [Universidade Federal Fluminense (TER/UFF), Niteroi, RJ (Brazil). Dept. de Engenharia Mecanica
2008-07-01
Different vegetable oils were characterized using standardized methods. The evaluated characteristics were density, viscosity, flow point, cloud point and corrosion. The obtained data was tabulated and compared with average composition values of oils in percentage of fatty acids and iodine number for each oil. In this analysis it is shown that viscosity decreases with the increase of the iodine number, and density decrease. The cloud and flow point have greater relation with the presence of saturated or highly unsaturated fatty acids, respectively. The index of corrosion is greater when oil saturation or its iodine number are increased. (author)
Submitted by
Physics Week: plenary meeting on physics groups plans for startup (14–15 May 2008) The Physics Objects (POG) and Physics Analysis (PAG) Groups presented their latest developments at the plenary meeting during the Physics Week. In the presentations particular attention was given to startup plans and readiness for data-taking. Many results based on the recent cosmic run were shown. A special Workshop on SUSY, described in a separate section, took place the day before the plenary. At the meeting, we had also two special DPG presentations on “Tracker and Muon alignment with CRAFT” (Ernesto Migliore) and “Calorimeter studies with CRAFT” (Chiara Rovelli). We had also a report from Offline (Andrea Rizzi) and Computing (Markus Klute) on the San Diego Workshop, described elsewhere in this bulletin. Tracking group (Boris Mangano). The level of sophistication of the tracking software increased significantly over the last few months: V0 (K0 and Λ) reconstr...
Coupled harmonic oscillators and their quantum entanglement
Makarov, Dmitry N.
2018-04-01
A system of two coupled quantum harmonic oscillators with the Hamiltonian H ̂=1/2 (1/m1p̂1 2+1/m2p̂2 2+A x12+B x22+C x1x2) can be found in many applications of quantum and nonlinear physics, molecular chemistry, and biophysics. The stationary wave function of such a system is known, but its use for the analysis of quantum entanglement is complicated because of the complexity of computing the Schmidt modes. Moreover, there is no exact analytical solution to the nonstationary Schrodinger equation H ̂Ψ =i ℏ ∂/Ψ ∂ t and Schmidt modes for such a dynamic system. In this paper we find a solution to the nonstationary Schrodinger equation; we also find in an analytical form a solution to the Schmidt mode for both stationary and dynamic problems. On the basis of the Schmidt modes, the quantum entanglement of the system under consideration is analyzed. It is shown that for certain parameters of the system, quantum entanglement can be very large.
International Nuclear Information System (INIS)
Menten, Fabio; Cheze, Benoit; Patouillard, Laure; Bouvart, Frederique
2013-01-01
This article presents the results of a literature review performs with a meta-regression analysis (MRA) that focuses on the estimates of advanced biofuel Greenhouse Gas (GHG) emissions assessed with a Life Cycle Assessment (LCA) approach. The mean GHG emissions of both second (G2) and third generation (G3) biofuels and the effects of factors influencing these estimates are identified and quantified by means of specific statistical methods. 47 LCA studies are included in the database, providing 593 estimates. Each study estimate of the database is characterized by i) technical data/characteristics, ii) author's methodological choices and iii) typology of the study under consideration. The database is composed of both the vector of these estimates - expressed in grams of CO 2 equivalent per MJ of biofuel (g CO 2 eq/MJ) - and a matrix containing vectors of predictor variables which can be continuous or dummy variables. The former is the dependent variable while the latter corresponds to the explanatory variables of the meta-regression model. Parameters are estimated by mean of econometrics methods. Our results clearly highlight a hierarchy between G3 and G2 biofuels: life cycle GHG emissions of G3 biofuels are statistically higher than those of Ethanol which, in turn, are superior to those of BtL. Moreover, this article finds empirical support for many of the hypotheses formulated in narrative literature surveys concerning potential factors which may explain estimates variations. Finally, the MRA results are used to address the harmonization issue in the field of advanced biofuels GHG emissions thanks to the technique of benefits transfer using meta-regression models. The range of values hence obtained appears to be lower than the fossil fuel reference (about 83.8 in g CO 2 eq/ MJ). However, only Ethanol and BtL do comply with the GHG emission reduction thresholds for biofuels defined in both the American and European directives. (authors)
Li, J.; Song, X.; Wang, P.; Zhu, L.
2017-12-01
The H-κ method (Zhu and Kanamori, 2000) has been widely used to estimate the crustal thickness and Vp/Vs ratio with receiver functions. However, in regions where the crustal structure is complicated, the method may produce uncertain or even unrealistic results, arising particularly from dipping Moho and/or crustal anisotropy. Here, we propose an improved H-κ method, which corrects for these effects first before stacking. The effect of dipping Moho and crustal anisotropy on Ps receiver function has been well studied, but not as much on crustal multiples (PpPs and PpSs+PsPs). Synthetic tests show that the effect of crustal anisotropy on the multiples are similar to Ps, while the effect of dipping Moho on the multiples is 5 times that on Ps (same cosine trend but 5 times in time shift). A Harmonic Analysis (HA) method for dipping/anisotropy was developed by Wang et al. (2017) for crustal Ps receiver functions to extract parameters of dipping Moho and crustal azimuthal anisotropy. In real data, the crustal multiples are much more complicated than the Ps. Therefore, we use the HA method (Wang et al., 2017), but apply separately to Ps and the multiples. It shows that although complicated, the trend of multiples can still be reasonably well represented by the HA. We then perform separate azimuthal corrections for Ps and the multiples and stack to obtain a combined receiver function. Lastly, the traditional H-κ procedure is applied to the stacked receiver function. We apply the improved H-κ method on 40 CNDSN (Chinese National Digital Seismic Network) stations distributed in a variety of geological setting across the Chinese continent. The results show apparent improvement compared to the traditional H-κ method, with clearer traces of multiples and stronger stacking energy in the grid search, as well as more reliable H-κ values.
Second-harmonic scanning optical microscopy of poled silica waveguides
DEFF Research Database (Denmark)
Pedersen, Kjeld; Bozhevolnyi, Sergey I.; Arentoft, Jesper
2000-01-01
Second-harmonic scanning optical microscopy (SHSOM) is performed on electric-field poled silica-based waveguides. Two operation modes of SHSOM are considered. Oblique transmission reflection and normal reflection modes are used to image the spatial distribution of nonlinear susceptibilities...... and limitations of the two operation modes when used for SHSOM studies of poled silica-based waveguides are discussed. The influence of surface defects on the resulting second-harmonic images is also considered. ©2000 American Institute of Physics....
The physics analysis environment of the ZEUS experiment
International Nuclear Information System (INIS)
Bauerdick, L.A.T.; Derugin, O.; Gilkinson, D.; Kasemann, M.; Manczak, O.
1995-12-01
The ZEUS Experiment has over the last three years developed its own model of the central computing environment for physics analysis. This model has been designed to provide ZEUS physicists with powerful and user friendly tools for data analysis as well as to be truly scalable and open. (orig.)
Tissue Harmonic Synthetic Aperture Imaging
DEFF Research Database (Denmark)
Rasmussen, Joachim
The main purpose of this PhD project is to develop an ultrasonic method for tissue harmonic synthetic aperture imaging. The motivation is to advance the field of synthetic aperture imaging in ultrasound, which has shown great potentials in the clinic. Suggestions for synthetic aperture tissue...... system complexity compared to conventional synthetic aperture techniques. In this project, SASB is sought combined with a pulse inversion technique for 2nd harmonic tissue harmonic imaging. The advantages in tissue harmonic imaging (THI) are expected to further improve the image quality of SASB...
Electron cyclotron harmonic wave acceleration
Karimabadi, H.; Menyuk, C. R.; Sprangle, P.; Vlahos, L.
1987-01-01
A nonlinear analysis of particle acceleration in a finite bandwidth, obliquely propagating electromagnetic cyclotron wave is presented. It has been suggested by Sprangle and Vlahos in 1983 that the narrow bandwidth cyclotron radiation emitted by the unstable electron distribution inside a flaring solar loop can accelerate electrons outside the loop by the interaction of a monochromatic wave propagating along the ambient magnetic field with the ambient electrons. It is shown here that electrons gyrating and streaming along a uniform, static magnetic field can be accelerated by interacting with the fundamental or second harmonic of a monochromatic, obliquely propagating cyclotron wave. It is also shown that the acceleration is virtually unchanged when a wave with finite bandwidth is considered. This acceleration mechanism can explain the observed high-energy electrons in type III bursts.
Electron cyclotron harmonic wave acceleration
International Nuclear Information System (INIS)
Karimabadi, H.; Menyuk, C.R.; Sprangle, P.; Vlahos, L.; Salonika Univ., Greece)
1987-01-01
A nonlinear analysis of particle acceleration in a finite bandwidth, obliquely propagating electromagnetic cyclotron wave is presented. It has been suggested by Sprangle and Vlahos in 1983 that the narrow bandwidth cyclotron radiation emitted by the unstable electron distribution inside a flaring solar loop can accelerate electrons outside the loop by the interaction of a monochromatic wave propagating along the ambient magnetic field with the ambient electrons. It is shown here that electrons gyrating and streaming along a uniform, static magnetic field can be accelerated by interacting with the fundamental or second harmonic of a monochromatic, obliquely propagating cyclotron wave. It is also shown that the acceleration is virtually unchanged when a wave with finite bandwidth is considered. This acceleration mechanism can explain the observed high-energy electrons in type III bursts. 31 references
Spinorial analysis and physical properties of fermions
International Nuclear Information System (INIS)
Krechet, V.G.
1987-01-01
The authors study the formalism of covariant differentiation of a spinor field in a space of affine connection with an invariant metric. They find the most general formula for the coefficients of spinorial connection Gamma/sub α/ consistent with the fundamental relationship between the space and spin (γ/sub α/γ/sup β/ + γ/sub β/γ/sub α/ = 2g/sub αβ/), and which is a generalization of the formula for the Fock-Ivanenko coefficients. The obtained formula contains additional terms describing the interaction between the spinor field and the scalar field, the vector field A/sub α/, and the pseudovector field A/sub α/ (presumably, the pseudotrace of the spacetime torsion). The existence of these interaction terms also follows from the analysis of spinor fields from the gauge-theoretical point of view. They show that the interaction between the spinor and pseudovector fields found in this paper substantially modifies the electrodynamics of spinor fields
Harmonic analysis and tidal prediction
Digital Repository Service at National Institute of Oceanography (India)
Fernandes, A.A.
stream_size 10 stream_content_type text/plain stream_name Trg_Calculat_Water_Depth_Chart_Datum_1991_12.pdf.txt stream_source_info Trg_Calculat_Water_Depth_Chart_Datum_1991_12.pdf.txt Content-Encoding ISO-8859-1 Content-Type text.../plain; charset=ISO-8859-1 ...
Pairwise harmonics for shape analysis
Zheng, Youyi; Tai, Chiewlan; Zhang, Eugene; Xu, Pengfei
2013-01-01
efficient algorithms than the state-of-the-art methods for three applications: intrinsic reflectional symmetry axis computation, matching shape extremities, and simultaneous surface segmentation and skeletonization. © 2012 IEEE.
Hecke algebras and harmonic analysis
Opdam, E.M.; Sanz-Solé, M.; Soria, J.; Varona, J.L.; Verdera, J.
2006-01-01
The International Congress of Mathematicians (ICM) is held every four years. It is a major scientific event, bringing together mathematicians from all over the world, and demonstrating the vital role that mathematics play in our society. In particular, the Fields Medals are awarded to recognize
M. Pavlovsky; A. Shimansky; Z. Fialkovsky
2004-01-01
The paper considers a power system model of a plant with one capacitor bank and with one current source of higher harmonics for higher power factor. The laboratory research results of this system and practical application of the proposed model are given in the paper.
Directory of Open Access Journals (Sweden)
M. Pavlovsky
2004-01-01
Full Text Available The paper considers a power system model of a plant with one capacitor bank and with one current source of higher harmonics for higher power factor. The laboratory research results of this system and practical application of the proposed model are given in the paper.
The International Politics of IFRS Harmonization
Ramanna, Karthik
2013-01-01
The globalization of accounting standards as seen through the proliferation of IFRS worldwide is one of the most important developments in corporate governance over the last decade. I offer an analysis of some international political dynamics of countries' IFRS harmonization decisions. The analysis is based on field studies in three jurisdictions: Canada, China, and India. Across these jurisdictions, I first describe unique elements of domestic political economies that are shaping IFRS polici...
Second-harmonic generation of practical Bessel beams
Huang, Jin H.; Ding, Desheng; Hsu, Yin-Sung
2009-11-01
A fast Gaussian expansion approach is used to investigate fundamental and second-harmonic generation in practical Bessel beams of finite aperture. The analysis is based on the integral solutions of the KZK equation under the quasilinear approximation. The influence of the medium's attenuation on the beam profile is considered. Analysis results show that the absorption parameter has a significant effect on the far-field beam profile of the second harmonic. Under certain circumstances, the second harmonic of a practical Bessel beam still has the main properties of an ideal Bessel beam of infinite aperture when it propagates within its depth of field.
Energy Technology Data Exchange (ETDEWEB)
Loganathan, Muthukumaran; Bristow, Douglas A., E-mail: dbristow@mst.edu [Department of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, Missouri 65401 (United States)
2014-04-15
This paper presents a method and cantilever design for improving the mechanical measurement sensitivity in the atomic force microscopy (AFM) tapping mode. The method uses two harmonics in the drive signal to generate a bi-harmonic tapping trajectory. Mathematical analysis demonstrates that the wide-valley bi-harmonic tapping trajectory is as much as 70% more sensitive to changes in the sample topography than the standard single-harmonic trajectory typically used. Although standard AFM cantilevers can be driven in the bi-harmonic tapping trajectory, they require large forcing at the second harmonic. A design is presented for a bi-harmonic cantilever that has a second resonant mode at twice its first resonant mode, thereby capable of generating bi-harmonic trajectories with small forcing signals. Bi-harmonic cantilevers are fabricated by milling a small cantilever on the interior of a standard cantilever probe using a focused ion beam. Bi-harmonic drive signals are derived for standard cantilevers and bi-harmonic cantilevers. Experimental results demonstrate better than 30% improvement in measurement sensitivity using the bi-harmonic cantilever. Images obtained through bi-harmonic tapping exhibit improved sharpness and surface tracking, especially at high scan speeds and low force fields.
Loganathan, Muthukumaran; Bristow, Douglas A
2014-04-01
This paper presents a method and cantilever design for improving the mechanical measurement sensitivity in the atomic force microscopy (AFM) tapping mode. The method uses two harmonics in the drive signal to generate a bi-harmonic tapping trajectory. Mathematical analysis demonstrates that the wide-valley bi-harmonic tapping trajectory is as much as 70% more sensitive to changes in the sample topography than the standard single-harmonic trajectory typically used. Although standard AFM cantilevers can be driven in the bi-harmonic tapping trajectory, they require large forcing at the second harmonic. A design is presented for a bi-harmonic cantilever that has a second resonant mode at twice its first resonant mode, thereby capable of generating bi-harmonic trajectories with small forcing signals. Bi-harmonic cantilevers are fabricated by milling a small cantilever on the interior of a standard cantilever probe using a focused ion beam. Bi-harmonic drive signals are derived for standard cantilevers and bi-harmonic cantilevers. Experimental results demonstrate better than 30% improvement in measurement sensitivity using the bi-harmonic cantilever. Images obtained through bi-harmonic tapping exhibit improved sharpness and surface tracking, especially at high scan speeds and low force fields.
Progress of the DUPIC fuel compatibility analysis (I) - reactor physics
Energy Technology Data Exchange (ETDEWEB)
Choi, Hang Bok; Jeong, Chang Joon; Roh, Gyu Hong; Rhee, Bo Wook; Park, Jee Won
2003-12-01
Since 1992, the direct use of spent pressurized water reactor fuel in CANada Deuterium Uranium (CANDU) reactors (DUPIC) has been studied as an alternative to the once-through fuel cycle. The DUPIC fuel cycle study is focused on the technical feasibility analysis, the fabrication of DUPIC fuels for irradiation tests and the demonstration of the DUPIC fuel performance. The feasibility analysis was conducted for the compatibility of the DUPIC fuel with existing CANDU-6 reactors from the viewpoints of reactor physics, reactor safety, fuel cycle economics, etc. This study has summarized the intermediate results of the DUPIC fuel compatibility analysis, which includes the CANDU reactor physics design requirements, DUPIC fuel core physics design method, performance of the DUPIC fuel core, regional overpower trip setpoint, and the CANDU primary shielding. The physics analysis showed that the CANDU-6 reactor can accommodate the DUPIC fuel without deteriorating the physics design requirements by adjusting the fuel management scheme if the fissile content of the DUPIC fuel is tightly controlled.
Investigation of Student Reasoning about Harmonic Motions
Tongnopparat, N.; Poonyawatpornkul, J.; Wattanakasiwich, P.
This study aimed to investigate student reasoning about harmonic oscillations. We conducted a semi-structured interview based on three situations of harmonic motions—(1) a mass attaching to spring and horizontally oscillating without damping, (2) the same situation but vertically oscillating and (3) a mass attaching to spring and oscillating in viscous liquid. Forty-five second-year students taking a vibrations and wave course at Chiang Mai University, Thailand participated in a fifteen-minute interview, which was video-recorded. The videos were transcribed and analyzed by three physics instructors. As results, we found that most students had misconceptions about angular frequency and energy mostly in the second and third situations.
Azimuthal anisotropy: The higher harmonics
International Nuclear Information System (INIS)
Poskanzer, Arthur M.; STAR Collaboration
2004-01-01
We report the first observations of the fourth harmonic (v 4 ) in the azimuthal distribution of particles at RHIC. The measurement was done taking advantage of the large elliptic flow generated at RHIC. The integrated v 4 is about a factor of 10 smaller than v 2 . For the sixth (v 6 ) and eighth (v 8 ) harmonics upper limits on the magnitudes are reported
Harmonic Series Meets Fibonacci Sequence
Chen, Hongwei; Kennedy, Chris
2012-01-01
The terms of a conditionally convergent series may be rearranged to converge to any prescribed real value. What if the harmonic series is grouped into Fibonacci length blocks? Or the harmonic series is arranged in alternating Fibonacci length blocks? Or rearranged and alternated into separate blocks of even and odd terms of Fibonacci length?
Stator Current Harmonic Control with Resonant Controller for Doubly Fed Induction Generator
DEFF Research Database (Denmark)
Liu, Changjin; Blaabjerg, Frede; Chen, Wenjie
2012-01-01
rotor current control loop for harmonic suppression. The overall control scheme is implemented in dq frame. Based on a mathematical model of the DFIG control system, the effects on system stability using the resonant controller, an analysis of the steady-state error, and the dynamic performance......, are discussed in this paper. Taking these effects into account, the parameters of the resonant controller can be designed and effectively damp the influence from the grid voltage harmonics. As a result, the impacts of the negative sequence fifth- and positive sequence seventh-order voltage harmonics...... harmonics, especially low-order harmonics. This paper proposes a stator current harmonic suppression method using a sixth-order resonant controller to eliminate negative sequence fifth- and positive sequence seventh-order current harmonics. A stator current harmonic control loop is added to the conventional...
Harmonics in transmission power systems
DEFF Research Database (Denmark)
Wiechowski, Wojciech Tomasz
. The comparison shows that results obtained used both types of the cores are the same, so it is concluded that both cores can be used for harmonic measurements. Low-inductance resistors are introduced in the secondary circuits, in series with the metering and protective relaying. On those resistors, the harmonic......Some time ago, Energinet.dk, the Transmission System Operator of the 150 kV and 400 kV transmission network in Denmark, had experienced operational malfunctions of some of the measuring and protection equipment. Also an overloading of a harmonic filter has been reported, and therefore, a need...... end only so the ground is not used as a return path. A way to reduce the capacitive coupling is to provide shielding. Harmonic currents are measured using the conventional inductive voltage transformers. Both protective and metering cores were compared if they could be used for harmonic measurements...
International Nuclear Information System (INIS)
Hillebrand, C.D.
1999-05-01
An analysis of the literature on Condensed Matter Physics, with particular emphasis on High Temperature Superconductors, was performed on the contents of the bibliographic database International Nuclear Information System (INIS). Quantitative data were obtained on various characteristics of the relevant INIS records such as subject categories, language and country of publication, publication types, etc. The analysis opens up the possibility for further studies, e.g. on international research co-operation and on publication patterns. (author)
J. Incandela
The all-plenary format of the CMS week in Cyprus gave the opportunity to the conveners of the physics groups to present the plans of each physics analysis group for tackling early physics analyses. The presentations were complete, so all are encouraged to browse through them on the Web. There is a wealth of information on what is going on, by whom and on what basis and priority. The CMS week was followed by two CMS “physics events”, the ICHEP08 days and the physics days in July. These were two weeks dedicated to either the approval of all the results that would be presented at ICHEP08, or to the review of all the other Monte-Carlo based analyses that were carried out in the context of our preparations for analysis with the early LHC data (the so-called “2008 analyses”). All this was planned in the context of the beginning of a ramp down of these Monte Carlo efforts, in anticipation of data. The ICHEP days are described below (agenda and talks at: http://indic...
Physics-based deformable organisms for medical image analysis
Hamarneh, Ghassan; McIntosh, Chris
2005-04-01
Previously, "Deformable organisms" were introduced as a novel paradigm for medical image analysis that uses artificial life modelling concepts. Deformable organisms were designed to complement the classical bottom-up deformable models methodologies (geometrical and physical layers), with top-down intelligent deformation control mechanisms (behavioral and cognitive layers). However, a true physical layer was absent and in order to complete medical image segmentation tasks, deformable organisms relied on pure geometry-based shape deformations guided by sensory data, prior structural knowledge, and expert-generated schedules of behaviors. In this paper we introduce the use of physics-based shape deformations within the deformable organisms framework yielding additional robustness by allowing intuitive real-time user guidance and interaction when necessary. We present the results of applying our physics-based deformable organisms, with an underlying dynamic spring-mass mesh model, to segmenting and labelling the corpus callosum in 2D midsagittal magnetic resonance images.
Analysis of lifestyle and physical culture and sports of students
Directory of Open Access Journals (Sweden)
Ol’ga P. Kokoulina
2016-01-01
Full Text Available The article reviewed the importance and necessity of sport and physical education at the present stage. The article describes the trend of health deterioration of young people as the consequence of a wrong lifestyle, alcohol, tobacco products, narcotic drugs‘use. The reasons of disregard for the healthy lifestyle and the consequences of misuse of the daily routine are presented.The reasons of the emergence and sport development and its history, the analysis of sport nature and physical education in the modern society were also considered in this article. It is shown the necessity and importance of sports and physical education at the present stage of the society development. Some factors that prevent globalization and widespread dissemination of sport and physical culture were introduced. Possible ways of solving these problems were put forward, motivational sphere for the formation of the active position in the field of healthy lifestyle was proposed in the research.
Physics Metacognition Inventory Part II: Confirmatory factor analysis and Rasch analysis
Taasoobshirazi, Gita; Bailey, MarLynn; Farley, John
2015-11-01
The Physics Metacognition Inventory was developed to measure physics students' metacognition for problem solving. In one of our earlier studies, an exploratory factor analysis provided evidence of preliminary construct validity, revealing six components of students' metacognition when solving physics problems including knowledge of cognition, planning, monitoring, evaluation, debugging, and information management. The college students' scores on the inventory were found to be reliable and related to students' physics motivation and physics grade. However, the results of the exploratory factor analysis indicated that the questionnaire could be revised to improve its construct validity. The goal of this study was to revise the questionnaire and establish its construct validity through a confirmatory factor analysis. In addition, a Rasch analysis was applied to the data to better understand the psychometric properties of the inventory and to further evaluate the construct validity. Results indicated that the final, revised inventory is a valid, reliable, and efficient tool for assessing student metacognition for physics problem solving.
Harmonics radiation of graphene surface plasmon polaritons in terahertz regime
Energy Technology Data Exchange (ETDEWEB)
Li, D., E-mail: dazhi_li@hotmail.com [Institute for Laser Technology, Suita, Osaka 565-0871 (Japan); Wang, Y. [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China); Nakajima, M. [Institute of Laser Engineering, Osaka University, Suita, Osaka 565-0871 (Japan); Hashida, M. [Advanced Research Center for Beam Science, ICR, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Wei, Y. [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China); Miyamoto, S. [Laboratory of Advanced Science and Technology for Industry, University of Hyogo, Ako, Hyogo 678-1205 (Japan)
2016-06-03
This letter presents an approach to extract terahertz radiation from surface plasmon polaritons excited in the surface of a uniform graphene structure by an electron beam. A sidewall configuration is proposed to lift the surface plasmon mode to be close to the light line, so that some of its harmonics have chances to go above the light line and become radiative. The harmonics are considered to be excited by a train of periodic electron bunches. The physical mechanism in this scheme is analyzed with three-dimensional theory, and the harmonics excitation and radiation are demonstrated through numerical calculations. The results show that this technique could be an alternative to transform the surface plasmon polaritons into radiation. - Highlights: • An approach to extract terahertz radiation from graphene surface plasmon polaritons is presented. • A sidewall configuration is proposed to lift the surface plasmon mode. • Harmonics of surface plasmon polaritons are possible to radiate.
TopView - ATLAS top physics analysis package
Shibata, A
2007-01-01
TopView is a common analysis package which is widely used in the ATLAS top physics working group. The package is fully based on the official ATLAS software Athena and EventView and playing a central role in the collaborative analysis model. It is a functional package which accounts for a broad range issues in implementing physics analysis. As well as being a modular framework suitable as a common workplace for collaborators, TopView implements numerous analysis tools including a complete top-antitop reconstruction and single top reconstruction. The package is currently used to produce common ntuple from Monte Carlo production and future use cases are under rapid development. In this paper, the design and ideas behind TopView and the performance of the analyses implemented in the package are presented with detailed documentation of the contents and instruction for using the package.
Research and analyze of physical health using multiple regression analysis
Directory of Open Access Journals (Sweden)
T. S. Kyi
2014-01-01
Full Text Available This paper represents the research which is trying to create a mathematical model of the "healthy people" using the method of regression analysis. The factors are the physical parameters of the person (such as heart rate, lung capacity, blood pressure, breath holding, weight height coefficient, flexibility of the spine, muscles of the shoulder belt, abdominal muscles, squatting, etc.., and the response variable is an indicator of physical working capacity. After performing multiple regression analysis, obtained useful multiple regression models that can predict the physical performance of boys the aged of fourteen to seventeen years. This paper represents the development of regression model for the sixteen year old boys and analyzed results.
Ma, Chen-xi; Ding, Guo-qing
2017-10-01
Simple harmonic waves and synthesized simple harmonic waves are widely used in the test of instruments. However, because of the errors caused by clearance of gear and time-delay error of FPGA, it is difficult to control servo electric cylinder in precise simple harmonic motion under high speed, high frequency and large load conditions. To solve the problem, a method of error compensation is proposed in this paper. In the method, a displacement sensor is fitted on the piston rod of the electric cylinder. By using the displacement sensor, the real-time displacement of the piston rod is obtained and fed back to the input of servo motor, then a closed loop control is realized. There is compensation of pulses in the next period of the synthetic waves. This paper uses FPGA as the processing core. The software mainly comprises a waveform generator, an Ethernet module, a memory module, a pulse generator, a pulse selector, a protection module, an error compensation module. A durability of shock absorbers is used as the testing platform. The durability mainly comprises a single electric cylinder, a servo motor for driving the electric cylinder, and the servo motor driver.
Application of econometric and ecology analysis methods in physics software
Han, Min Cheol; Hoff, Gabriela; Kim, Chan Hyeong; Kim, Sung Hun; Grazia Pia, Maria; Ronchieri, Elisabetta; Saracco, Paolo
2017-10-01
Some data analysis methods typically used in econometric studies and in ecology have been evaluated and applied in physics software environments. They concern the evolution of observables through objective identification of change points and trends, and measurements of inequality, diversity and evenness across a data set. Within each analysis area, various statistical tests and measures have been examined. This conference paper summarizes a brief overview of some of these methods.
Comprehensive physical analysis of bond wire interfaces in power modules
DEFF Research Database (Denmark)
Popok, Vladimir; Pedersen, Kristian Bonderup; Kristensen, Peter Kjær
2016-01-01
causing failures. In this paper we present a review on the set of our experimental and theoretical studies allowing comprehensive physical analysis of changes in materials under active power cycling with focus on bond wire interfaces and thin metallisation layers. The developed electro-thermal and thermo...
24 CFR 401.451 - PAE Physical Condition Analysis (PCA).
2010-04-01
... (PCA). 401.451 Section 401.451 Housing and Urban Development Regulations Relating to Housing and Urban... PROGRAM (MARK-TO-MARKET) Restructuring Plan § 401.451 PAE Physical Condition Analysis (PCA). (a) Review... of the project by means of a PCA. If the PAE finds any immediate threats to health and safety, the...
Methodology for reactor core physics analysis - part 2
International Nuclear Information System (INIS)
Ponzoni Filho, P.; Fernandes, V.B.; Lima Bezerra, J. de; Santos, T.I.C.
1992-12-01
The computer codes used for reactor core physics analysis are described. The modifications introduced in the public codes and the technical basis for the codes developed by the FURNAS utility are justified. An evaluation of the impact of these modifications on the parameter involved in qualifying the methodology is included. (F.E.). 5 ref, 7 figs, 5 tabs
Automatic computation and solution of generalized harmonic balance equations
Peyton Jones, J. C.; Yaser, K. S. A.; Stevenson, J.
2018-02-01
Generalized methods are presented for generating and solving the harmonic balance equations for a broad class of nonlinear differential or difference equations and for a general set of harmonics chosen by the user. In particular, a new algorithm for automatically generating the Jacobian of the balance equations enables efficient solution of these equations using continuation methods. Efficient numeric validation techniques are also presented, and the combined algorithm is applied to the analysis of dc, fundamental, second and third harmonic response of a nonlinear automotive damper.
Higher-order harmonics of general limited diffraction Bessel beams
International Nuclear Information System (INIS)
Ding De-Sheng; Huang Jin-Huang
2016-01-01
In this paper, we extensively study the higher-order harmonic generation of the general limited diffraction m -th-order Bessel beam. The analysis is based on successive approximations of the Khokhlov–Zabolotskaya–Kuznetsov (KZK) equation. Asymptotic expansions are presented for higher-order harmonic Bessel beams in near and far fields. The validity of asymptotic approximation is also analyzed. The higher-order harmonic of the Bessel beam with the lowest zero-order is taken as a special example. (special topic)
Higher-order harmonics of general limited diffraction Bessel beams
Ding, De-Sheng; Huang, Jin-Huang
2016-12-01
In this paper, we extensively study the higher-order harmonic generation of the general limited diffraction m-th-order Bessel beam. The analysis is based on successive approximations of the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation. Asymptotic expansions are presented for higher-order harmonic Bessel beams in near and far fields. The validity of asymptotic approximation is also analyzed. The higher-order harmonic of the Bessel beam with the lowest zero-order is taken as a special example. Project supported by the National Natural Science Foundation of China (Grant Nos. 11074038 and 11374051).
Harmonic operation of high gain harmonic generation free electron laser
International Nuclear Information System (INIS)
Deng Haixiao; Chinese Academy of Sciences, Beijing; Dai Zhimin
2008-01-01
In high gain harmonic generation (HGHG) free electron laser (FEL), with the right choice of parameters of the modulator undulator, the dispersive section and the seed laser, one may make the spatial bunching of the electron beam density distribution correspond to one of the harmonic frequencies of the radiator radiation, instead of the fundamental frequency of the radiator radiation in conventional HGHG, thus the radiator undulator is in harmonic operation (HO) mode. In this paper, we investigate HO of HGHG FEL. Theoretical analyses with universal method are derived and numerical simulations in ultraviolet and deep ultraviolet spectral regions are given. It shows that the power of the 3rd harmonic radiation in the HO of HGHG may be as high as 18.5% of the fundamental power level. Thus HO of HGHG FEL may obtain short wavelength by using lower beam energy. (authors)
Power system measurements in presence of harmonics. Misure nelle reti in presenza di armoniche
Energy Technology Data Exchange (ETDEWEB)
Pesavento, G. (Padua Univ. (Italy)); Rinaldi, M. (Bologna Univ. (Italy))
1993-03-01
The paper, after a short analysis of possible sources of harmonics and the range of frequencies of interest, deals with the problems related to the measurement of electrical quantities in the presence of distorted wave forms and non-linear loads. In general, the characteristics of available instrumentation are sufficient to provide a good accuracy; electronic apparatus, both analog and digital can easily reach bandwidths of several kHz. Among apparatus connected to power lines, voltage transformers appear to be critical from the point of view of bandwidth. Induction power meters are also affected by the presence of harmonics but, in normal cases, the resulting error is within a few percent margins. Problems arise with definitions related to specific quantities and with the associated physical meaning that might be lost when passing from sinusoidal to distorted conditions.
Prediction of Metastasis Using Second Harmonic Generation
2016-07-01
small but statistically significant difference in average F/B of treated US patients versus untreated Dutch patients. Fig. 1. Display of all...predictive ability of models incorporating F/B using a multivariate linear model, but this time applying the analysis to the entire ER+ and ER- cohort. As...AWARD NUMBER: W81XWH-15-1-0040 TITLE: Prediction of Metastasis Using Second Harmonic Generation PRINCIPAL INVESTIGATOR: Edward Brown
Analysis of foreign physical activity recommendations and guidelines for schools
Directory of Open Access Journals (Sweden)
Jan Pavelka
2014-06-01
Full Text Available Background:An adequate level of physical activity is an important part of children's lifestyle. The school environment plays a significant role in the area of interventions and strategies aiming to increase the level of physical activity in children. Objectives: The aim of this study is to analyse foreign recommendations leading to an increased level of physical activity in children and young people in Czech schools. Methods: A systematic search of studies published between 1988 and 2012 in the English language was completed in library databases Medline, Sport Discus, ProQuest, PsychInfo, ERIC, Wiley InterScience using the following keywords: physical activity, guidelines, recommendations, school and youth. The studies were then classified based on abstract and full-text analyses. Using a content analysis the expert team formulated the final recommendations to increase the level of physical activity for schools in the Czech Republic (CR. Results: Out of the total number of 91 identified foreign studies, 25 met the predetermined criteria and were used as a basis for formulating the recommendations. These foreign studies included 15 papers published in USA, two in Australia, two in Great Britain, two in Canada, one in the European Union, one in New Zealand and one international paper (an international consensus of experts from 34 countries. Based on the interpretation of the evidence, its justification and final consensus of the expert team, the basic areas for the recommendations to increase the level of physical activity in schools in the CR were identified. Conclusions: An analysis of foreign recommendations to increase the level of physical activity designed for schools and school facilities is one of the possible methods of formulating domestic recommendations. This recommendation could contribute to deeper understanding of the issue of the deteriorating lifestyle of school-aged children in the CR and reflects the efforts for improvement.
Power quality issues current harmonics
Mikkili, Suresh
2015-01-01
Power Quality Issues: Current Harmonics provides solutions for the mitigation of power quality problems related to harmonics. Focusing on active power filters (APFs) due to their excellent harmonic and reactive power compensation in two-wire (single phase), three-wire (three-phase without neutral), and four-wire (three-phase with neutral) AC power networks with nonlinear loads, the text:Introduces the APF technology, describing various APF configurations and offering guidelines for the selection of APFs for specific application considerationsCompares shunt active filter (SHAF) control strategi
Joe Incandela
There have been two plenary physics meetings since the December CMS week. The year started with two workshops, one on the measurements of the Standard Model necessary for “discovery physics” as well as one on the Physics Analysis Toolkit (PAT). Meanwhile the tail of the “2007 analyses” is going through the last steps of approval. It is expected that by the end of January all analyses will have converted to using the data from CSA07 – which include the effects of miscalibration and misalignment. January Physics Days The first Physics Days of 2008 took place on January 22-24. The first two days were devoted to comprehensive re¬ports from the Detector Performance Groups (DPG) and Physics Objects Groups (POG) on their planning and readiness for early data-taking followed by approvals of several recent studies. Highlights of POG presentations are included below while the activities of the DPGs are covered elsewhere in this bulletin. January 24th was devo...
Increasing physical activity with mobile devices: a meta-analysis.
Fanning, Jason; Mullen, Sean P; McAuley, Edward
2012-11-21
Regular physical activity has established physical and mental health benefits; however, merely one quarter of the U.S. adult population meets national physical activity recommendations. In an effort to engage individuals who do not meet these guidelines, researchers have utilized popular emerging technologies, including mobile devices (ie, personal digital assistants [PDAs], mobile phones). This study is the first to synthesize current research focused on the use of mobile devices for increasing physical activity. To conduct a meta-analysis of research utilizing mobile devices to influence physical activity behavior. The aims of this review were to: (1) examine the efficacy of mobile devices in the physical activity setting, (2) explore and discuss implementation of device features across studies, and (3) make recommendations for future intervention development. We searched electronic databases (PubMed, PsychINFO, SCOPUS) and identified publications through reference lists and requests to experts in the field of mobile health. Studies were included that provided original data and aimed to influence physical activity through dissemination or collection of intervention materials with a mobile device. Data were extracted to calculate effect sizes for individual studies, as were study descriptives. A random effects meta-analysis was conducted using the Comprehensive Meta-Analysis software suite. Study quality was assessed using the quality of execution portion of the Guide to Community Preventative Services data extraction form. Four studies were of "good" quality and seven of "fair" quality. In total, 1351 individuals participated in 11 unique studies from which 18 effects were extracted and synthesized, yielding an overall weight mean effect size of g = 0.54 (95% CI = 0.17 to 0.91, P = .01). Research utilizing mobile devices is gaining in popularity, and this study suggests that this platform is an effective means for influencing physical activity behavior. Our focus
Game theoretic analysis of physical protection system design
International Nuclear Information System (INIS)
Canion, B.; Schneider, E.; Bickel, E.; Hadlock, C.; Morton, D.
2013-01-01
The physical protection system (PPS) of a fictional small modular reactor (SMR) facility have been modeled as a platform for a game theoretic approach to security decision analysis. To demonstrate the game theoretic approach, a rational adversary with complete knowledge of the facility has been modeled attempting a sabotage attack. The adversary adjusts his decisions in response to investments made by the defender to enhance the security measures. This can lead to a conservative physical protection system design. Since defender upgrades were limited by a budget, cost benefit analysis may be conducted upon security upgrades. One approach to cost benefit analysis is the efficient frontier, which depicts the reduction in expected consequence per incremental increase in the security budget
Data management, archiving, visualization and analysis of space physics data
Russell, C. T.
1995-01-01
A series of programs for the visualization and analysis of space physics data has been developed at UCLA. In the course of those developments, a number of lessons have been learned regarding data management and data archiving, as well as data analysis. The issues now facing those wishing to develop such software, as well as the lessons learned, are reviewed. Modern media have eased many of the earlier problems of the physical volume required to store data, the speed of access, and the permanence of the records. However, the ultimate longevity of these media is still a question of debate. Finally, while software development has become easier, cost is still a limiting factor in developing visualization and analysis software.
Physics Structure Analysis of Parallel Waves Concept of Physics Teacher Candidate
International Nuclear Information System (INIS)
Sarwi, S; Linuwih, S; Supardi, K I
2017-01-01
The aim of this research was to find a parallel structure concept of wave physics and the factors that influence on the formation of parallel conceptions of physics teacher candidates. The method used qualitative research which types of cross-sectional design. These subjects were five of the third semester of basic physics and six of the fifth semester of wave course students. Data collection techniques used think aloud and written tests. Quantitative data were analysed with descriptive technique-percentage. The data analysis technique for belief and be aware of answers uses an explanatory analysis. Results of the research include: 1) the structure of the concept can be displayed through the illustration of a map containing the theoretical core, supplements the theory and phenomena that occur daily; 2) the trend of parallel conception of wave physics have been identified on the stationary waves, resonance of the sound and the propagation of transverse electromagnetic waves; 3) the influence on the parallel conception that reading textbooks less comprehensive and knowledge is partial understanding as forming the structure of the theory. (paper)
The Impact of Harmonics Calculation Methods on Power Quality Assessment in Wind Farms
DEFF Research Database (Denmark)
Kocewiak, Lukasz Hubert; Hjerrild, Jesper; Bak, Claus Leth
2010-01-01
Different methods of calculating harmonics in measurements obtained from offshore wind farms are shown in this paper. Appropriate data processing methods are suggested for harmonics with different origin and nature. Enhancements of discrete Fourier transform application in order to reduce...... measurement data processing errors are proposed and compared with classical methods. Comparison of signal processing methods for harmonic studies is presented and application dependent on harmonics origin and nature recommended. Certain aspects related to magnitude and phase calculation in stationary...... measurement data are analysed and described. Qualitative indices of measurement data harmonic analysis in order to assess the calculation accuracy are suggested and used....
Second-harmonic generation of Lamb modes in a solid layer supported by a semi-infinite substrate
International Nuclear Information System (INIS)
Deng Mingxi
2004-01-01
Using a second-order perturbation approximation and a modal expansion analysis approach, this study develops an effective technique for studying the generation of second harmonics of Lamb modes propagating in the composite structure consisting of a solid layer supported by a semi-infinite substrate. The nonlinearity in the elastic wave motion process can result in the generation of second harmonics of primary Lamb mode propagation in the composite structure, and this nonlinearity may be treated as a second-order perturbation of the elastic response of the primary waves. There are second-order bulk and surface/interface driving sources in the composite structure wherever the primary Lamb modes propagate. These driving sources can be thought of as the forcing functions of a finite series of double-frequency Lamb modes (DFLMs) in terms of the approach of modal expansion analysis for waveguide excitation. The fields of the second harmonics of the primary Lamb modes can be regarded as superpositions of the fields of a finite series of DFLMs. Although Lamb modes are dispersive, the field of one DFLM component can have a cumulative growth effect when its phase velocity exactly or approximately equals that of a primary Lamb mode. The formal solutions for the second harmonics of Lamb modes have been obtained. The numerical simulations clearly show the physical process of the generation of second harmonics of Lamb modes in the composite structure. The complicated problems of second-harmonic generation of Lamb modes have been exactly determined within the second-order perturbation approximation
West Coast Swing Dancing as a Driven Harmonic Oscillator Model
Ferrara, Davon; Holzer, Marie; Kyere, Shirley
The study of physics in sports not only provides valuable insight for improved athletic performance and injury prevention, but offers undergraduate students an opportunity to engage in both short- and long-term research efforts. In this project, conducted by two non-physics majors, we hypothesized that a driven harmonic oscillator model can be used to better understand the interaction between two west coast swing dancers since the stiffness of the physical connection between dance partners is a known factor in the dynamics of the dance. The hypothesis was tested by video analysis of two dancers performing a west coast swing basic, the sugar push, while changing the stiffness of the physical connection. The difference in stiffness of the connection from the ideal was estimated by the leader; the position with time data from the video was used to measure changes in the amplitude and phase difference between the leader and follower. While several aspects of our results agree with the proposed model, some key characteristics do not, possibly due to the follower relying on visual leads. Corresponding author and principal investigator.
D. Acosta
2010-01-01
The Physics Groups are actively engaged on analyses of the first data from the LHC at 7 TeV, targeting many results for the ICHEP conference taking place in Paris this summer. The first large batch of physics approvals is scheduled for this CMS Week, to be followed by four more weeks of approvals and analysis updates leading to the start of the conference in July. Several high priority analysis areas were organized into task forces to ensure sufficient coverage from the relevant detector, object, and analysis groups in the preparation of these analyses. Already some results on charged particle correlations and multiplicities in 7 TeV minimum bias collisions have been approved. Only one small detail remains before ICHEP: further integrated luminosity delivered by the LHC! Beyond the Standard Model measurements that can be done with these data, the focus changes to the search for new physics at the TeV scale and for the Higgs boson in the period after ICHEP. Particle Flow The PFT group is focusing on the ...
Explaining the harmonic sequence paradox.
Schmidt, Ulrich; Zimper, Alexander
2012-05-01
According to the harmonic sequence paradox, an expected utility decision maker's willingness to pay for a gamble whose expected payoffs evolve according to the harmonic series is finite if and only if his marginal utility of additional income becomes zero for rather low payoff levels. Since the assumption of zero marginal utility is implausible for finite payoff levels, expected utility theory - as well as its standard generalizations such as cumulative prospect theory - are apparently unable to explain a finite willingness to pay. This paper presents first an experimental study of the harmonic sequence paradox. Additionally, it demonstrates that the theoretical argument of the harmonic sequence paradox only applies to time-patient decision makers, whereas the paradox is easily avoided if time-impatience is introduced. ©2011 The British Psychological Society.
A Global Sensitivity Analysis Methodology for Multi-physics Applications
Energy Technology Data Exchange (ETDEWEB)
Tong, C H; Graziani, F R
2007-02-02
Experiments are conducted to draw inferences about an entire ensemble based on a selected number of observations. This applies to both physical experiments as well as computer experiments, the latter of which are performed by running the simulation models at different input configurations and analyzing the output responses. Computer experiments are instrumental in enabling model analyses such as uncertainty quantification and sensitivity analysis. This report focuses on a global sensitivity analysis methodology that relies on a divide-and-conquer strategy and uses intelligent computer experiments. The objective is to assess qualitatively and/or quantitatively how the variabilities of simulation output responses can be accounted for by input variabilities. We address global sensitivity analysis in three aspects: methodology, sampling/analysis strategies, and an implementation framework. The methodology consists of three major steps: (1) construct credible input ranges; (2) perform a parameter screening study; and (3) perform a quantitative sensitivity analysis on a reduced set of parameters. Once identified, research effort should be directed to the most sensitive parameters to reduce their uncertainty bounds. This process is repeated with tightened uncertainty bounds for the sensitive parameters until the output uncertainties become acceptable. To accommodate the needs of multi-physics application, this methodology should be recursively applied to individual physics modules. The methodology is also distinguished by an efficient technique for computing parameter interactions. Details for each step will be given using simple examples. Numerical results on large scale multi-physics applications will be available in another report. Computational techniques targeted for this methodology have been implemented in a software package called PSUADE.
Implementation of statistical analysis methods for medical physics data
International Nuclear Information System (INIS)
Teixeira, Marilia S.; Pinto, Nivia G.P.; Barroso, Regina C.; Oliveira, Luis F.
2009-01-01
The objective of biomedical research with different radiation natures is to contribute for the understanding of the basic physics and biochemistry of the biological systems, the disease diagnostic and the development of the therapeutic techniques. The main benefits are: the cure of tumors through the therapy, the anticipated detection of diseases through the diagnostic, the using as prophylactic mean for blood transfusion, etc. Therefore, for the better understanding of the biological interactions occurring after exposure to radiation, it is necessary for the optimization of therapeutic procedures and strategies for reduction of radioinduced effects. The group pf applied physics of the Physics Institute of UERJ have been working in the characterization of biological samples (human tissues, teeth, saliva, soil, plants, sediments, air, water, organic matrixes, ceramics, fossil material, among others) using X-rays diffraction and X-ray fluorescence. The application of these techniques for measurement, analysis and interpretation of the biological tissues characteristics are experimenting considerable interest in the Medical and Environmental Physics. All quantitative data analysis must be initiated with descriptive statistic calculation (means and standard deviations) in order to obtain a previous notion on what the analysis will reveal. It is well known que o high values of standard deviation found in experimental measurements of biologicals samples can be attributed to biological factors, due to the specific characteristics of each individual (age, gender, environment, alimentary habits, etc). This work has the main objective the development of a program for the use of specific statistic methods for the optimization of experimental data an analysis. The specialized programs for this analysis are proprietary, another objective of this work is the implementation of a code which is free and can be shared by the other research groups. As the program developed since the
Cohabiting with the harmonic pollution
International Nuclear Information System (INIS)
Garcia C, Antonio A
1999-01-01
The Norm IEEE 519 tries of the permissible limits of harmonic distortion in the point of common joining between the energy supplier company and the industry. However fulfilling these limits of distortion doesn't guarantee that the problem for the company has finished, on the contrary will have to counteract the effects created by the harmonic distortion toward the interior of its electric system and to cohabit with this distortion
The macroscopic harmonic oscillator and quantum measurements
International Nuclear Information System (INIS)
Hayward, R.W.
1982-01-01
A quantum mechanical description of a one-dimensional macroscopic harmonic oscillator interacting with its environment is given. Quasi-coherent states are introduced to serve as convenient basis states for application of a density matrix formalism to characterize the system. Attention is given to the pertinent quantum limits to the precision of measurement of physical observables that may provide some information on the nature of a weak classical force interacting with the oscillator. A number of ''quantum nondemolition'' schemes proposed by various authors are discussed. (Auth.)
A quantum harmonic oscillator and strong chaos
International Nuclear Information System (INIS)
Oprocha, Piotr
2006-01-01
It is known that many physical systems which do not exhibit deterministic chaos when treated classically may exhibit such behaviour if treated from the quantum mechanics point of view. In this paper, we will show that an annihilation operator of the unforced quantum harmonic oscillator exhibits distributional chaos as introduced in B Schweizer and J SmItal (1994 Trans. Am. Math. Soc. 344 737-54). Our approach strengthens previous results on chaos in this model and provides a very powerful tool to measure chaos in other (quantum or classical) models
HARMONIZATION OF CRITERIA AND TERMINOLOGY IN RABBIT MEAT RESEARCH
Blasco Mateu, Agustín; Ouhayoun, J.; Masoero, G.
1993-01-01
[EN] The harmonization of rabbit carcass criteria is a result of an international work. lts task was to specify the main traits to be considerad from the birth of the animal to carcass analysis, to define these traits with enough accuracy and to propose a common terminology. Work on harmonization has been initialized by the Mediterranean Rabbit Group Conference (BLASCO, OUHAYOUN and MASOERO, 1992), completad by several research teams and, finally, discussed during a round...
Real time physics analysis with the ATLAS tau trigger system
International Nuclear Information System (INIS)
Casado Lechuga, M. P.
2009-01-01
The scope of the ATLAS tau trigger system at the LHC is most ambitious. It aims at reconstructing in real time, a matter of seconds, a detailed picture of the high energy proton proton collisions at the LHC. Such system is mandatory in order to select efficiently data needed for discovery of new physics in a proton proton collision environment where the rates of jets observed in the detector are high and the tau identification is difficult. New physics scenarios targeted specifically by the the ATLAS tau trigger system are Standard Model or Supersymmetric Higgs production, and production of new exotic resonances. This contribution will detail how the analysis techniques developed offline for efficient data analysis have been implemented in the algorithms which run online at the trigger. In particular, the focus will be on how to satisfy the requirements imposed by the physics goals while addressing the limitations from the overall event rate and latency allowed. The prospects for early running during the first LHC collisions and trigger evolution from first collisions to stable running will be also summarized, following change of trigger goals from commissioning of detector to measurement of Standard Model physics and discoveries. (author)
Harmonic Resonances in Wind Power Plants
DEFF Research Database (Denmark)
Fernandez, Francisco Daniel Freijedo; Chaudhary, Sanjay; Teodorescu, Remus
2015-01-01
This work reviews the state-of-the-art in the field of harmonic resonance problems in Wind Power Plants (WPPs). Firstly, a generic WPP is modeled according to the equivalent circuits of its passive and active components. Main focus is put on modeling active components, i.e. the ones based on power...... 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....
Contrast-enhanced harmonic endoscopic ultrasound
DEFF Research Database (Denmark)
Săftoiu, A; Dietrich, C F; Vilmann, P
2012-01-01
Second-generation intravenous blood-pool ultrasound contrast agents are increasingly used in endoscopic ultrasound (EUS) for characterization of microvascularization, differential diagnosis of benign and malignant focal lesions, and improving staging and guidance of therapeutic procedures. Although...... initially used as Doppler signal enhancers, second-generation microbubble contrast agents are now used with specific contrast harmonic imaging techniques, which benefit from the highly nonlinear behavior of the microbubbles. Contrast-specific modes based on multi-pulse technology are used to perform...... contrast-enhanced harmonic EUS based on a very low mechanical index (0.08 - 0.12). Quantification techniques based on dynamic contrast-enhanced ultrasound have been recommended for perfusion imaging and monitoring of anti-angiogenic treatment, mainly based on time-intensity curve analysis. Most...
Spherical harmonics and integration in superspace
International Nuclear Information System (INIS)
Bie, H de; Sommen, F
2007-01-01
In this paper, the classical theory of spherical harmonics in R m is extended to superspace using techniques from Clifford analysis. After defining a super-Laplace operator and studying some basic properties of polynomial null-solutions of this operator, a new type of integration over the supersphere is introduced by exploiting the formal equivalence with an old result of Pizzetti. This integral is then used to prove orthogonality of spherical harmonics of different degree, Green-like theorems and also an extension of the important Funk-Hecke theorem to superspace. Finally, this integration over the supersphere is used to define an integral over the whole superspace, and it is proven that this is equivalent with the Berezin integral, thus providing a more sound definition of the Berezin integral
EUROPEAN HARMONIZATION OF CONSOLIDATED FINANCIAL STATEMENTS REGULATIONS?
Directory of Open Access Journals (Sweden)
Cirstea Andreea
2012-07-01
Full Text Available The purpose of this paper is to analyze the degree of formal accounting harmonization within the European Union with respect to the EC Regulation No. 1606/2002 adopted by the European Parliament and European Council on the 19th of July 2002, which regulates the application of IAS/IFRS regarding the financial reporting of listed European companies. The conclusions of the paper were drawn after the completion of a thorough analysis performed by using correlation and/ or association coefficients, namely: the JaccardÃ¢â‚¬â„¢s Correlation Coefficients, Rogers and Tanimoto Coefficient, Lance and Williams Coefficient and Binary Euclidian Distance Coefficient. The results lead us to conclude that although our first hypothesis is verified, the degree of harmonization between the accounting systems of EU Member States could be truly quantified only through an analysis of the material accounting harmonization, more precisely by analyzing the way the companies put into practice the requirements imposed through the EC Regulation No. 1606/2002.
Coherent harmonics generated by a super-short electron pulse
International Nuclear Information System (INIS)
Ding Wu
1996-01-01
A novel mechanism generating superradiance harmonics is found. In this superradiance harmonics, the temporal width of harmonics is extremely short, the ratio of high harmonic fundamental wave is much higher than the known superradiance harmonics
High-Speed Video Analysis in a Conceptual Physics Class
Desbien, Dwain M.
2011-09-01
The use of probe ware and computers has become quite common in introductory physics classrooms. Video analysis is also becoming more popular and is available to a wide range of students through commercially available and/or free software.2,3 Video analysis allows for the study of motions that cannot be easily measured in the traditional lab setting and also allows real-world situations to be analyzed. Many motions are too fast to easily be captured at the standard video frame rate of 30 frames per second (fps) employed by most video cameras. This paper will discuss using a consumer camera that can record high-frame-rate video in a college-level conceptual physics class. In particular this will involve the use of model rockets to determine the acceleration during the boost period right at launch and compare it to a simple model of the expected acceleration.
Topics in statistical data analysis for high-energy physics
International Nuclear Information System (INIS)
Cowan, G.
2011-01-01
These lectures concert two topics that are becoming increasingly important in the analysis of high-energy physics data: Bayesian statistics and multivariate methods. In the Bayesian approach, we extend the interpretation of probability not only to cover the frequency of repeatable outcomes but also to include a degree of belief. In this way we are able to associate probability with a hypothesis and thus to answer directly questions that cannot be addressed easily with traditional frequentist methods. In multivariate analysis, we try to exploit as much information as possible from the characteristics that we measure for each event to distinguish between event types. In particular we will look at a method that has gained popularity in high-energy physics in recent years: the boosted decision tree. Finally, we give a brief sketch of how multivariate methods may be applied in a search for a new signal process. (author)
Model-Based Dependability Analysis of Physical Systems with Modelica
Directory of Open Access Journals (Sweden)
Andrea Tundis
2017-01-01
Full Text Available Modelica is an innovative, equation-based, and acausal language that allows modeling complex physical systems, which are made of mechanical, electrical, and electrotechnical components, and evaluates their design through simulation techniques. Unfortunately, the increasing complexity and accuracy of such physical systems require new, more powerful, and flexible tools and techniques for evaluating important system properties and, in particular, the dependability ones such as reliability, safety, and maintainability. In this context, the paper describes some extensions of the Modelica language to support the modeling of system requirements and their relationships. Such extensions enable the requirement verification analysis through native constructs in the Modelica language. Furthermore, they allow exporting a Modelica-based system design as a Bayesian Network in order to analyze its dependability by employing a probabilistic approach. The proposal is exemplified through a case study concerning the dependability analysis of a Tank System.
General Lp-harmonic Blaschke bodies
Indian Academy of Sciences (India)
Abstract. Lutwak introduced the harmonic Blaschke combination and the harmonic. Blaschke body of a star body. Further, Feng and Wang introduced the concept of the L p- harmonic Blaschke body of a star body. In this paper, we define the notion of general. L p-harmonic Blaschke bodies and establish some of its ...
General Lp-harmonic Blaschke bodies
Indian Academy of Sciences (India)
Lutwak introduced the harmonic Blaschke combination and the harmonic Blaschke body of a star body. Further, Feng and Wang introduced the concept of the -harmonic Blaschke body of a star body. In this paper, we define the notion of general -harmonic Blaschke bodies and establish some of its properties.
Audibility of harmonics in 'periodic white noise'
Duifhuis, H.; Tomesen, H.H.
1970-01-01
In a previous article (Duifhuis, 1970) results' concerning the audibility of harmonics in a periodic pulse have been presented. Each of the lower harmonics could be perceived separately, whereas the high harmonics were heard together as one complex signal. High harmonics, however, appeared to be
Chris Hill
2012-01-01
The months that have passed since the last CMS Bulletin have been a very busy and exciting time for CMS physics. We have gone from observing the very first 8TeV collisions produced by the LHC to collecting a dataset of the collisions that already exceeds that recorded in all of 2011. All in just a few months! Meanwhile, the analysis of the 2011 dataset and publication of the subsequent results has continued. These results come from all the PAGs in CMS, including searches for the Higgs boson and other new phenomena, that have set the most stringent limits on an ever increasing number of models of physics beyond the Standard Model including dark matter, Supersymmetry, and TeV-scale gravity scenarios, top-quark physics where CMS has overtaken the Tevatron in the precision of some measurements, and bottom-quark physics where CMS made its first discovery of a new particle, the Ξ*0b baryon (candidate event pictured below). Image 2: A Ξ*0b candidate event At the same time POGs and PAGs...
IDAL: an interactive analysis language for high energy physics
International Nuclear Information System (INIS)
Burnett, T.H.
1990-01-01
The SLAC e + e - experiment SLD has adopted a unique off-line software environment, IDA. It provides a command processor shell for all code, from reconstruction and Monte Carlo production to user DST physics analysis. An essential component is an incrementally-compiled language, IDAL. IDAL allows symbolic access to SLD data structures, and supports special loop constructs to allow examination of all banks of a given type. IDAL also recognizes statements that simultaneously define histograms and generate code to fill them
Continuum methods of physical modeling continuum mechanics, dimensional analysis, turbulence
Hutter, Kolumban
2004-01-01
The book unifies classical continuum mechanics and turbulence modeling, i.e. the same fundamental concepts are used to derive model equations for material behaviour and turbulence closure and complements these with methods of dimensional analysis. The intention is to equip the reader with the ability to understand the complex nonlinear modeling in material behaviour and turbulence closure as well as to derive or invent his own models. Examples are mostly taken from environmental physics and geophysics.
Quantum Physics in high school: a bakhtinian analysis of Physics textbooks approved at PNLDEM 2015
Directory of Open Access Journals (Sweden)
Nathan Willig Lima
2017-08-01
Full Text Available In this work we present an analysis of Quantum Physics texts present in the fourteen books approved by the National Textbook Plan for High School in 2015. We used Bakhtin’s Philosophy of Language as a theoretical and methodological framework. Our aim was to evaluate which approaches are used by textbook authors to introduce Quantum Physics as well as which concepts and epistemological views are stated in these presentations. Our results show that all books present a historical approach, limited to the Old Quantum Physics. Concepts and presentation sequences are very similar to what can be found in Modern Physics undergraduate textbooks, containing even the same historiographic mistakes. This suggests that authors state what they have learned during undergraduate courses without any further critical review. All books present lexical choice that can be associated to positivist epistemology, and thirteen books present a compositional structure allied to the same view, which is considered epistemologically outdated. The reductionist textbook presentation indicates the necessity of breaking up with the hegemonic positivist perspective.
the PAG conveners
2011-01-01
The delivered LHC integrated luminosity of more than 1 inverse femtobarn by summer and more than 5 by the end of 2011 has been a gold mine for the physics groups. With 2011 data, we have submitted or published 14 papers, 7 others are in collaboration-wide review, and 75 Physics Analysis Summaries have been approved already. They add to the 73 papers already published based on the 2010 and 2009 datasets. Highlights from each physics analysis group are described below. Heavy ions Many important results have been obtained from the first lead-ion collision run in 2010. The published measurements include the first ever indications of Υ excited state suppression (PRL synopsis), long-range correlation in PbPb, and track multiplicity over a wide η range. Preliminary results include the first ever measurement of isolated photons (showing no modification), J/ψ suppression including the separation of the non-prompt component, further study of jet fragmentation, nuclear modification factor...
Preliminary Safety Analysis Report for the Tokamak Physics Experiment
International Nuclear Information System (INIS)
Motloch, C.G.; Bonney, R.F.; Levine, J.D.; Masson, L.S.; Commander, J.C.
1995-04-01
This Preliminary Safety Analysis Report (PSAR), includes an indication of the magnitude of facility hazards, complexity of facility operations, and the stage of the facility life-cycle. It presents the results of safety analyses, safety assurance programs, identified vulnerabilities, compensatory measures, and, in general, the rationale describing why the Tokamak Physics Experiment (TPX) can be safely operated. It discusses application of the graded approach to the TPX safety analysis, including the basis for using Department of Energy (DOE) Order 5480.23 and DOE-STD-3009-94 in the development of the PSAR
Meta-Analysis of Workplace Physical Activity Interventions
Conn, Vicki S.; Hafdahl, Adam R.; Cooper, Pamela S.; Brown, Lori M.; Lusk, Sally L.
2009-01-01
Context Most adults do not achieve adequate physical activity. Despite the potential benefits of worksite health promotion, no previous comprehensive meta-analysis has summarized health and physical activity behavior outcomes from these programs. This comprehensive meta-analysis integrated the extant wide range of worksite physical activity intervention research. Evidence acquisition Extensive searching located published and unpublished intervention studies reported from 1969 through 2007. Results were coded from primary studies. Random-effects meta-analytic procedures, including moderator analyses, were completed in 2008. Evidence synthesis Effects on most variables were substantially heterogeneous because diverse studies were included. Standardized mean difference (d) effect sizes were synthesized across approximately 38,231 subjects. Significantly positive effects were observed for physical activity behavior (0.21), fitness (0.57), lipids (0.13), anthropometric measures (0.08), work attendance (0.19), and job stress (0.33). The significant effect size for diabetes risk (0.98) is more tentative given small sample sizes. Significant heterogeneity documents intervention effects varied across studies. The mean effect size for fitness corresponds to a difference between treatment minus control subjects' means on V02max of 3.5 mL/kg/min; for lipids, −0.2 on total cholesterol:HDL; and for diabetes risk, −12.6 mg/dL on fasting glucose. Conclusions These findings document that some workplace physical activity interventions can improve both health and important worksite outcomes. Effects were variable for most outcomes, reflecting the diversity of primary studies. Future primary research should compare interventions to confirm causal relationships and further explore heterogeneity. PMID:19765506
Meta-analysis of workplace physical activity interventions.
Conn, Vicki S; Hafdahl, Adam R; Cooper, Pamela S; Brown, Lori M; Lusk, Sally L
2009-10-01
Most adults do not achieve adequate physical activity levels. Despite the potential benefits of worksite health promotion, no previous comprehensive meta-analysis has summarized health and physical activity behavior outcomes from such programs. This comprehensive meta-analysis integrated the extant wide range of worksite physical activity intervention research. Extensive searching located published and unpublished intervention studies reported from 1969 through 2007. Results were coded from primary studies. Random-effects meta-analytic procedures, including moderator analyses, were completed in 2008. Effects on most variables were substantially heterogeneous because diverse studies were included. Standardized mean difference (d) effect sizes were synthesized across approximately 38,231 subjects. Significantly positive effects were observed for physical activity behavior (0.21); fitness (0.57); lipids (0.13); anthropometric measures (0.08); work attendance (0.19); and job stress (0.33). The significant effect size for diabetes risk (0.98) is less robust given small sample sizes. The mean effect size for fitness corresponds to a difference between treatment minus control subjects' means on VO2max of 3.5 mL/kg/min; for lipids, -0.2 on the ratio of total cholesterol to high-density lipoprotein; and for diabetes risk, -12.6 mg/dL on fasting glucose. These findings document that some workplace physical activity interventions can improve both health and important worksite outcomes. Effects were variable for most outcomes, reflecting the diversity of primary studies. Future primary research should compare interventions to confirm causal relationships and further explore heterogeneity.
Physics analysis of the gang partial rod drive event
International Nuclear Information System (INIS)
Boman, C.; Frost, R.L.
1992-08-01
During the routine positioning of partial-length control rods in Gang 3 on the afternoon of Monday, July 27, 1992, the partial-length rods continued to drive into the reactor even after the operator released the controlling toggle switch. In response to this occurrence, the Safety Analysis and Engineering Services Group (SAEG) requested that the Applied Physics Group (APG) analyze the gang partial rod drive event. Although similar accident scenarios were considered in analysis for Chapter 15 of the Safety Analysis Report (SAR), APG and SAEG conferred and agreed that this particular type of gang partial-length rod motion event was not included in the SAR. This report details this analysis
Li, Abby A; Sheets, Larry P; Raffaele, Kathleen; Moser, Virginia; Hofstra, Angela; Hoberman, Alan; Makris, Susan L; Garman, Robert; Bolon, Brad; Kaufmann, Wolfgang; Auer, Roland; Lau, Edmund; Vidmar, Thomas; Bowers, Wayne J
2017-09-01
and analysis, and expectations in DNT data that are encountered by regulatory authorities. In addition, principles for harmonized evaluation of data were suggested using guideline DNT data as case studies. Copyright © 2017. Published by Elsevier Inc.
ARTIFICIAL INTELLIGENT SYSTEM FOR MEASUREMENT OF HARMONIC POWERS
Directory of Open Access Journals (Sweden)
Jovitha Jerome
2017-11-01
Full Text Available The importance of the electric power quality (PQ demands new methodologies and measurement tools in the power industry for the analysis and measurement of the basic electric magnitudes necessary. This paper presents a new measurement procedure based on neural networks for the estimation of harmonic amplitudes of current/voltage and respective harmonic powers. The measurement scheme is built with two neural network modules. The first module is an adaptive linear neuron (ADALINE that is the kernel part of estimation of complex harmonic coefficients of the current/voltage. The second module is feedforward neural network that obtains the harmonic active/reactive powers. In order to perform digital simulation the Feedforward and Adaline neural network tools were developed in LabVIEW. This measurement algorithm was tested for the practical cases and found to be robust, computationally fast and efficient.
A Kalman-filter estimate of the tidal harmonic constants
International Nuclear Information System (INIS)
Morsetti, R.
1983-01-01
A Kalman-filter estimate of the tidal harmonic constants is proposed in order to take into account their stochastic behaviour. The filter algorithm has been applied to a state-space model of a stochastic system in which the state is defined by the harmonic constants themselves. The results, analysing Trieste sea-level data, have demonstrated that this approach is very suitable for such a purpose, since good estimates and excellent resolution capabilities have been obtained. Furthermore, this method can be very useful also from a practical point of view because real-time computation of the harmonic constants can be developed where an opportune sea-level data acquisition system is available. In conclusion, this paper has emphasized that tidal harmonic constants have to be treated like random variables and, in consequence, new method of analysis can be used
Harmonic and power balance tools for tapping-mode atomic force microscope
International Nuclear Information System (INIS)
Sebastian, A.; Salapaka, M. V.; Chen, D. J.; Cleveland, J. P.
2001-01-01
The atomic force microscope (AFM) is a powerful tool for investigating surfaces at atomic scales. Harmonic balance and power balance techniques are introduced to analyze the tapping-mode dynamics of the atomic force microscope. The harmonic balance perspective explains observations hitherto unexplained in the AFM literature. A nonconservative model for the cantilever - sample interaction is developed. The energy dissipation in the sample is studied and the resulting power balance equations combined with the harmonic balance equations are used to estimate the model parameters. Experimental results confirm that the harmonic and power balance tools can be used effectively to predict the behavior of the tapping cantilever. [copyright] 2001 American Institute of Physics
Energy Technology Data Exchange (ETDEWEB)
Vanya, Ignatova
2006-10-15
The power quality concerns all the actors in the energy domains, that they are network administrators, suppliers, producers, or consumers of electricity. The research work presented in this PhD thesis is situated in the field of the power quality monitoring. Its objective is to introduce new techniques for analysis of power quality problems. There are different methods designed for the analysis of the power quality disturbances. This method reaches very good performances in the voltage dips analysis, as it allows segmenting, classifying and characterising these power quality disturbances. The periodic systems method allows the theoretical study of the generation and the propagation of harmonic disturbances in the network. Finally, the statistical matrix method has the objective to represent statistically electrical signals without loss of important information. (author)
Harmonic filter design consideration for a tire-rubber factory
Energy Technology Data Exchange (ETDEWEB)
Zebardast, A. [Azad Univ., Tehran (Iran, Islamic Republic of). Abhar Branch]|[Sharif Univ., Tehran (Iran, Islamic Republic of); Mokhtari, H. [Azad Univ., Tehran (Iran, Islamic Republic of)
2005-07-01
Nonlinear loads and arc furnace loads are the main sources of harmonic currents in power distribution systems. Harmonic currents can cause reductions in system efficiency, and shorten the lifespan of transformers and capacitor banks. This paper provided details of a filter designed to attenuate harmonic currents at a tire company in Iran. The tire company was supplied by 3 distribution transformers and an emergency transformer. Main supply was through a 132 kV/20 kV transformer, which was connected to 2 A and B stations. The AC/DC drivers generated harmonics. Harmonic measurements were performed to determine the type and size of the required filters. A summary of site harmonic measurements was provided. A passive filter was placed at a medium voltage location. A sensitivity analysis was then performed in order to assess loading effects on filter performance. The analysis was performed on all possible configurations in the plant, including load change, capacitor bank step change, and transformer energization. Resonance conditions were also examined. Results showed that attention must be paid to the filter component rating in addition to potential resonant conditions. It was concluded that resonant conditions alter when system operating conditions change. 5 refs., 7 figs.
High-brightness high-order harmonic generation at 13 nm with a long gas jet
International Nuclear Information System (INIS)
Kim, Hyung Taek; Kim, I Jong; Lee, Dong Gun; Park, Jong Ju; Hong, Kyung Han; Nam, Chang Hee
2002-01-01
The generation of high-order harmonics is well-known method producing coherent extreme-ultraviolet radiation with pulse duration in the femtosecond regime. High-order harmonics have attracted much attention due to their unique features such as coherence, ultrashort pulse duration, and table-top scale system. Due to these unique properties, high-order harmonics have many applications of atomic and molecular spectroscopy, plasma diagnostics and solid-state physics. Bright generation of high-order harmonics is important for actual applications. Especially, the generation of strong well-collimated harmonics at 13 nm can be useful for the metrology of EUV lithography optics because of the high reflectivity of Mo-Si mirrors at this wavelength. The generation of bright high-order harmonics is rather difficult in the wavelength region below 15nm. Though argon and xenon gases have large conversion efficiency, harmonic generation from these gases is restricted to wavelengths over 20 nm due to low ionization potential. Hence, we choose neon for the harmonic generation around 13 nm; it has larger conversion efficiency than helium and higher ionization potential than argon. In this experiment, we have observed enhanced harmonic generation efficiency and low beam divergence of high-order harmonics from a elongated neon gas jet by the enhancement of laser propagation in an elongated gas jet. A uniform plasma column was produced when the gas jet was exposed to converging laser pulses.
Means of Harmonization in Religious Discourse
Directory of Open Access Journals (Sweden)
Irina Ščukina
2012-12-01
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 extra-linguistic 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 story-telling. Rational and unemotional sermonic discourse is perceived as a sign of respect (namely, for the listener's intelligence. Another successful and much-applied way seems to be evoking a feeling of equality, unity and/or identity between clerics and their flocks.
Phase-dependent quantum interference between different pathways in bichromatic harmonic generation
International Nuclear Information System (INIS)
Jun, Cai; Li-Ming, Wang; Hao-Xue, Qiao
2009-01-01
This paper studies the harmonic generation of the hydrogen atom subjected to a collinear bichromatic laser field by numerically solving the time-dependent Schrödinger equation using the split-operator pseudo-spectral method. By adding a frequency variation to the additional field, the contributions of different pathways to particular order harmonic generation can be isolated. The quantum interference pattern between harmonic pathways, which influences the harmonic intensity, is found to be either constructive or destructive with respect to different relative phase of the two field components. Detailed description of up to the 35th-order harmonics and the harmonic pathways for a wide range of field parameters is presented. (atomic and molecular physics)
A simple mechanical model for the isotropic harmonic oscillator
International Nuclear Information System (INIS)
Nita, Gelu M
2010-01-01
A constrained elastic pendulum is proposed as a simple mechanical model for the isotropic harmonic oscillator. The conceptual and mathematical simplicity of this model recommends it as an effective pedagogical tool in teaching basic physics concepts at advanced high school and introductory undergraduate course levels.
Exact complex integrals in two dimensions for shifted harmonic ...
Indian Academy of Sciences (India)
We use rationalization method to study two-dimensional complex dynamical systems (shifted harmonic oscillator in complex plane) on the extended comples phase space (ECPS). The role and scope of the derived invatiants in the context of various physical problems are high-lighted.
Physical macroeconomics: a demarcation of accounting and analysis
Energy Technology Data Exchange (ETDEWEB)
Hahn, M. de [Statistics Netherlands, Voorburg (Netherlands)
2001-07-01
This paper provides a general discussion on physical flow accounting methodology. The discussion is limited to those methods primarily applied to the national economy level. Specific attention is given to the demarcation of accounting versus analysis. The primary goal of statistics and accounting is to provide an acceptable level of 'descriptiveness' and 'neutrality' in its representation of facts. On the other hand, modelling or analysis usually relies on assumptions of a much wider scale, for example in relation to human behaviour, or by the necessity of ceteris paribus clauses in partial analysis. While accounting usually provides answers on past events, analysis is often ex-ante oriented. A number of accounting methods are reviewed on the basis of their accounting scopes and indicator proposals. In general the accounting frameworks are rather complementary or at least not contradictory but inconsistencies emerge in some of the indicators that are derived from the accounts. The paper further elaborates on the significance of the national accounts in this field of research. National accounting concepts and definitions contributes to a sound demarcation of the (national) economy, which appears equally valid for physical representations of a national economy. This demarcation also supports the sound allocation of environmental burdens to specific national or regional economies. At the same time, the economic relevance of physical flows is to a large extent exposed by their connection to specific economic (production and consumption) processes and concomitant transactions. This linkage, as for example accommodated in a National Accounting Matrix including Environmental Accounts (NAMEA) provides in this respect a useful statistical framework that provides a consistent comparison of environmental burdens to economic benefits (or environmental benefits to economic costs)
Perkó, Z.
2015-01-01
This thesis presents novel adjoint and spectral methods for the sensitivity and uncertainty (S&U) analysis of multi-physics problems encountered in the field of reactor physics. The first part focuses on the steady state of reactors and extends the adjoint sensitivity analysis methods well
L. Demortier
Physics-wise, the CMS week in December was dominated by discussions of the analyses that will be carried out in the “next six months”, i.e. while waiting for the first LHC collisions. As presented in December, analysis approvals based on Monte Carlo simulation were re-opened, with the caveat that for this work to be helpful to the goals of CMS, it should be carried out using the new software (CMSSW_2_X) and associated samples. By the end of the week, the goal for the physics groups was set to be the porting of our physics commissioning methods and plans, as well as the early analyses (based an integrated luminosity in the range 10-100pb-1) into this new software. Since December, the large data samples from CMSSW_2_1 were completed. A big effort by the production group gave a significant number of events over the end-of-year break – but also gave out the first samples with the fast simulation. Meanwhile, as mentioned in December, the arrival of 2_2 meant that ...
(1 + 1) Newton-Hooke group for the simple and damped harmonic oscillator
Brzykcy, Przemysław
2018-03-01
It is demonstrated that, in the framework of the orbit method, a simple and damped harmonic oscillator is indistinguishable at the level of an abstract Lie algebra. This opens a possibility for treating the dissipative systems within the orbit method. An in-depth analysis of the coadjoint orbits of the (1 + 1) dimensional Newton-Hooke group is presented. Furthermore, it is argued that the physical interpretation is carried by a specific realisation of the Lie algebra of smooth functions on a phase space rather than by an abstract Lie algebra.
Multipole lenses with implicit poles and with harmonic distribution of current density in a coil
International Nuclear Information System (INIS)
Skachkov, V.S.
1984-01-01
General theory of the multipole lense with implicit poles is presented. The thickness of lense coil is finite. Current density distribution in the coil cross section is harmonic in the azimuth direction and arbitrary in the radial one. The calculation of yoke contribution in the lence field is given. Two particular lense variants differing from each other in the method of current density radial distribution are considered and necessary calculated relations for the lense with and without yoke ar presented. A comparative analysis of physical and technological peculiarities of these lenses is performed
Directory of Open Access Journals (Sweden)
Gbeminiyi Sobamowo
2017-04-01
Full Text Available The development of mathematical models for describing the dynamic behaviours of fluid conveying pipes, micro-pipes and nanotubes under the influence of some thermo-mechanical parameters results into nonlinear equations that are very difficult to solve analytically. In cases where the exact analytical solutions are presented either in implicit or explicit forms, high skills and rigorous mathematical analyses were employed. It is noted that such solutions do not provide general exact solutions. Inevitably, comparatively simple, flexible yet accurate and practicable solutions are required for the analyses of these structures. Therefore, in this study, approximate analytical solutions are provided to the nonlinear equations arising in flow-induced vibration of pipes, micro-pipes and nanotubes using Galerkin-Newton-Harmonic Method (GNHM. The developed approximate analytical solutions are shown to be valid for both small and large amplitude oscillations. The accuracies and explicitness of these solutions were examined in limiting cases to establish the suitability of the method.
Kitchen Physics: Lessons in Fluid Pressure and Error Analysis
Vieyra, Rebecca Elizabeth; Vieyra, Chrystian; Macchia, Stefano
2017-02-01
Although the advent and popularization of the "flipped classroom" tends to center around at-home video lectures, teachers are increasingly turning to at-home labs for enhanced student engagement. This paper describes two simple at-home experiments that can be accomplished in the kitchen. The first experiment analyzes the density of four liquids using a waterproof case and a smartphone barometer in a container, sink, or tub. The second experiment determines the relationship between pressure and temperature of an ideal gas in a constant volume container placed momentarily in a refrigerator freezer. These experiences provide a ripe opportunity both for learning fundamental physics concepts as well as to investigate a variety of error analysis techniques that are frequently overlooked in introductory physics courses.
Toward the automated analysis of plasma physics problems
International Nuclear Information System (INIS)
Mynick, H.E.
1989-04-01
A program (CALC) is described, which carries out nontrivial plasma physics calculations, in a manner intended to emulate the approach of a human theorist. This includes the initial process of gathering the relevant equations from a plasma knowledge base, and then determining how to solve them. Solution of the sets of equations governing physics problems, which in general have a nonuniform,irregular structure, not amenable to solution by standardized algorithmic procedures, is facilitated by an analysis of the structure of the equations and the relations among them. This often permits decompositions of the full problem into subproblems, and other simplifications in form, which renders the resultant subsystems soluble by more standardized tools. CALC's operation is illustrated by a detailed description of its treatment of a sample plasma calculation. 5 refs., 3 figs
Disability in physical education textbooks: an analysis of image content.
Táboas-Pais, María Inés; Rey-Cao, Ana
2012-10-01
The aim of this paper is to show how images of disability are portrayed in physical education textbooks for secondary schools in Spain. The sample was composed of 3,316 images published in 36 textbooks by 10 publishing houses. A content analysis was carried out using a coding scheme based on categories employed in other similar studies and adapted to the requirements of this study with additional categories. The variables were camera angle, gender, type of physical activity, field of practice, space, and level. Univariate and bivariate descriptive analyses were also carried out. The Pearson chi-square statistic was used to identify associations between the variables. Results showed a noticeable imbalance between people with disabilities and people without disabilities, and women with disabilities were less frequently represented than men with disabilities. People with disabilities were depicted as participating in a very limited variety of segregated, competitive, and elite sports activities.
Christopher Hill
2013-01-01
Since the last CMS Bulletin, the CMS Physics Analysis Groups have completed more than 70 new analyses, many of which are based on the complete Run 1 dataset. In parallel the Snowmass whitepaper on projected discovery potential of CMS for HL-LHC has been completed, while the ECFA HL-LHC future physics studies has been summarised in a report and nine published benchmark analyses. Run 1 summary studies on b-tag and jet identification, quark-gluon discrimination and boosted topologies have been documented in BTV-13-001 and JME-13-002/005/006, respectively. The new tracking alignment and performance papers are being prepared for submission as well. The Higgs analysis group produced several new results including the search for ttH with H decaying to ZZ, WW, ττ+bb (HIG-13-019/020) where an excess of ~2.5σ is observed in the like-sign di-muon channel, and new searches for high-mass Higgs bosons (HIG-13-022). Search for invisible Higgs decays have also been performed both using the associ...
C. Hill
2013-01-01
In the period since the last CMS Bulletin, the LHC – and CMS – have entered LS1. During this time, CMS Physics Analysis Groups have performed more than 40 new analyses, many of which are based on the complete 8 TeV dataset delivered by the LHC in 2012 (and in some cases on the full Run 1 dataset). These results were shown at, and well received by, several high-profile conferences in the spring of 2013, including the inaugural meeting of the Large Hadron Collider Physics Conference (LHCP) in Barcelona, and the 26th International Symposium on Lepton Photon Interactions at High Energies (LP) in San Francisco. In parallel, there have been significant developments in preparations for Run 2 of the LHC and on “future physics” studies for both Phase 1 and Phase 2 upgrades of the CMS detector. The Higgs analysis group produced five new results for LHCP including a new H-to-bb search in VBF production (HIG-13-011), ttH with H to γ&ga...
C. Hill
2013-01-01
The period since the last CMS bulletin has seen the end of proton collisions at a centre-of-mass energy 8 TeV, a successful proton-lead collision run at 5 TeV/nucleon, as well as a “reference” proton run at 2.76 TeV. With these final LHC Run 1 datasets in hand, CMS Physics Analysis Groups have been busy analysing these data in preparation for the winter conferences. Moreover, despite the fact that the pp run only concluded in mid-December (and there was consequently less time to complete data analyses), CMS again made a strong showing at the Rencontres de Moriond in La Thuile (EW and QCD) where nearly 40 new results were presented. The highlight of these preliminary results was the eagerly anticipated updated studies of the properties of the Higgs boson discovered in July of last year. Meanwhile, preparations for Run 2 and physics performance studies for Phase 1 and Phase 2 upgrade scenarios are ongoing. The Higgs analysis group produced updated analyses on the full Run 1 dataset (~25 f...
HARMONIZED EUROPE OR EUROPEAN HARMONY?
Directory of Open Access Journals (Sweden)
Cosmin Marinescu
2007-07-01
Full Text Available Recent evolutions in Europe raise questions on the viability of the present economic and social model that defines the European construction project. In this paper, the author will try to explain the viability of institutional European model that sticks between free market mechanisms and protectionism. The main challenge for the EU is about the possibility to bring together the institutional convergence and the welfare for all Europeans. This is the result of the view, still dominant, of European politics elite, according to which institutional harmonization is the solution of a more dynamic and prosper Europe. But, economic realities convince us that, more and more, a harmonized, standardized Europe is not necessarily identical with a Europe of harmony and social cooperation. If „development through integration” seems to be harmonization through „institutional transplant”, how could then be the European model one sufficiently wide open to market, which creates the prosperity so long waited for by new member countries?
Harmonic superspaces of extended supersymmetry
International Nuclear Information System (INIS)
Ivanov, E.; Kalitzin, S.; Nguyen Ai Viet; Ogievetsky, V.
1984-01-01
The main technical apparatus of the harmonic superspace approach to extended SUSY, the calculus of harmonic variables on homogeneous spaces of the SUSY automorphism groups, is presented in detail for N=2, 3, 4. The basic harmonics for the coset manifolds G/H with G=SU(2), H=U(1); G=SU(3), H=SU(2)xU(1) and H=U(1)xU(1); G=SU(4), H=SU(3)xU(1), H=SU(2)xSU(2)xU(1), H=SU(2)xU(1)xU(1) and H=U(1)xU(1)xU(1); G=USp(2), H=SU(2)xSU(2), H=SU(2)xU(1) and H=U(1)xU(1) are tabulated a number of useful relations among them
Physical explosion analysis in heat exchanger network design
Pasha, M.; Zaini, D.; Shariff, A. M.
2016-06-01
The failure of shell and tube heat exchangers is being extensively experienced by the chemical process industries. This failure can create a loss of production for long time duration. Moreover, loss of containment through heat exchanger could potentially lead to a credible event such as fire, explosion and toxic release. There is a need to analyse the possible worst case effect originated from the loss of containment of the heat exchanger at the early design stage. Physical explosion analysis during the heat exchanger network design is presented in this work. Baker and Prugh explosion models are deployed for assessing the explosion effect. Microsoft Excel integrated with process design simulator through object linking and embedded (OLE) automation for this analysis. Aspen HYSYS V (8.0) used as a simulation platform in this work. A typical heat exchanger network of steam reforming and shift conversion process was presented as a case study. It is investigated from this analysis that overpressure generated from the physical explosion of each heat exchanger can be estimated in a more precise manner by using Prugh model. The present work could potentially assist the design engineer to identify the critical heat exchanger in the network at the preliminary design stage.