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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D Model Schrödinger Equation RMS KLEIN GORDON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow Attraction REPULSION Shell Theorem Ehrenfest VIRIAL Normalization Harmonic Oscillator
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Instantaneous Active and Reactive Power and Current Strategies for Current harmonics cancellation in 3-ph 4wire SHAF With both PI and Fuzzy Controllers 被引量:1
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作者 Suresh Mikkili Anup Kumar Panda 《Energy and Power Engineering》 2011年第3期285-298,共14页
Control strategies for extracting the three-phase reference currents for shunt active power filters are compared, evaluating their performance under different source conditions with PI and Fuzzy Controllers in MATLAB/... Control strategies for extracting the three-phase reference currents for shunt active power filters are compared, evaluating their performance under different source conditions with PI and Fuzzy Controllers in MATLAB/Simulink environment When the supply voltages are balanced and sinusoidal, the two control strategies are converge to the same compensation characteristics;However, the supply voltages are distorted and/or un-balanced sinusoidal, these control strategies result in different degrees of compensation in harmonics. The compensation capabilities are not equivalent, with p - q control strategy unable to yield an adequate solution when source voltages are not ideal. Extensive simulations are carried out with PI controller and also with Fuzzy controller for both p-q and Id-Iq control strategies under different main voltages. Extensive Simulations are carried out with PI as well as fuzzy controller for both p-q and Id - Iq control strategies by considering different voltage conditions and adequate results were presented. On owing Id - Iq method with fuzzy logic controller gives away an out-standing performance under any voltage conditions (balanced, un-balanced, balanced and non-sinusoidal). 展开更多
关键词 Harmonic Compensation Shunt ACTIVE Filter (SHAF) p-q CONTROL STRATEGY id-iq CONTROL STRATEGY PI CONTROLLER and Fuzzy CONTROLLER
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Fuzzy and PI Controller Based SHAF for Mitigation of Current Harmonics with P-Q Method Using Matlab and RTDS Hardware
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作者 Suresh Mikkili Anup Kumar Panda 《Energy and Power Engineering》 2011年第4期407-421,共15页
The main objective of this paper is to develop PI and Fuzzy logic controllers to analyse the performance of instantaneous real active and reactive power (p-q) control strategy for extracting reference currents of shun... The main objective of this paper is to develop PI and Fuzzy logic controllers to analyse the performance of instantaneous real active and reactive power (p-q) control strategy for extracting reference currents of shunt active filters under balanced, un-balanced and balanced non-sinusoidal conditions. When the supply voltages are balanced and sinusoidal, then all controllers converge to the same compensation characteristics. However, when the supply voltages are distorted and/or un-balanced sinusoidal, these control strategies result in different degrees of compensation in harmonics. The p-q control strategy with PI controller is unable to yield an adequate solution when source voltages are not ideal. Extensive simulations were carried out;simulations were performed with balance, unbalanced and non sinusoidal conditions. Simulation results validate the dynamic behaviour of Fuzzy logic controller over PI controller. The 3-ph 4-wire SHAF system is also implemented on a Real Time Digital Simulator (RTDS Hardware) to further verify its effectiveness. The detailed simulation and RTDS Hardware results are included. 展开更多
关键词 Harmonic Compensation Shunt Active Filter (SHAF) P-Q Control Strategy PI CONTROLLER FUZZY CONTROLLER RTDS HARDWARE
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Fibonacci Harmonics: A New Mathematical Model of Synchronicity
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作者 Robert G. Sacco 《Applied Mathematics》 2018年第6期702-718,共17页
This article aims to provide a brief overview of the relevance of new findings about the Fibonacci Life Chart Method (FLCM) for understanding synchronicity. The FLCM is reviewed first, including an exposition of the g... This article aims to provide a brief overview of the relevance of new findings about the Fibonacci Life Chart Method (FLCM) for understanding synchronicity. The FLCM is reviewed first, including an exposition of the golden section model, and elaboration of a new harmonic model. The two models are then compared to illuminate several strengths and weaknesses in connection with the following four major criteria regarding synchronicity: explanatory adequacy;predictability of future synchronicities;simplicity of the model;and generalizability to other branches of knowledge. The review indicates that both models appear capable of simulating nonlinear and fractal dynamics. Hybrid approaches that combine both models are feasible and necessary for projects that aim to experimentally address synchronicity. 展开更多
关键词 SYNCHRONICITY Dynamical Systems Brain Dynamics FIBONACCI Life CHART Method GOLDEN Section MODEL Harmonic MODEL
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Fuzzy Controller Based 3Phase 4Wire Shunt Active Filter for Mitigation of Current Harmonics with Combined p-q and Id-Iq Control Strategies 被引量:4
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作者 Mikkili Suresh Anup Kumar Panda Y. Suresh 《Energy and Power Engineering》 2011年第1期43-52,共10页
As more and more variable frequency drives (VFDs), electronic ballasts, battery chargers, and static Var compensators are installed in facilities, the problems related to harmonics are expected to get worse. As a resu... As more and more variable frequency drives (VFDs), electronic ballasts, battery chargers, and static Var compensators are installed in facilities, the problems related to harmonics are expected to get worse. As a result Active power filter (APF) gains much more attention due to excellent harmonic compensation. But still the performance of the active filter seems to be in contradictions with different control strategies. This paper presents detailed analysis to compare and elevate the performance of two control strategies for ex-tracting reference currents of shunt active filters under balanced, un-balanced and non-sinusoidal conditions by using Fuzzy controller. The well known methods, instantaneous real active and reactive power method (p-q) and active and reactive current method (id-iq) are two control methods which are extensively used in active filters. Extensive Simulations are carried out with fuzzy controller for both p-q and Id-Iq methods for different voltage conditions and adequate results were presented. Simulation results validate the superior per-formance of active and reactive current control strategy (id-iq) with fuzzy controller over active and reactive power control strategy (p-q) with fuzzy controller. 展开更多
关键词 HARMONIC Compensation SHUNT Active Power Filter p-q CONTROL STRATEGY id-iq CONTROL STRATEGY Fuzzy Controller
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Effects of Harmonics on Power Loss in XLPE Cables
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作者 W. Z. Gandhare K. D. Patil 《Energy and Power Engineering》 2013年第4期1235-1239,共5页
Harmonics in power systems is increasingly at high level. Also, there has been an incredible growth in the use of cross linked polyethylene (XLPE) cables in distribution systems. Harmonics cause additional power loss/... Harmonics in power systems is increasingly at high level. Also, there has been an incredible growth in the use of cross linked polyethylene (XLPE) cables in distribution systems. Harmonics cause additional power loss/temperature rise;causing premature failure of cables. Catastrophic failure of power cables leads to great inconvenience to consumers and loss of system reliability and money. To avoid the overheating of power cables;the additional power loss due to harmonics should be accurately calculated and properly accommodated by derating the cable. The present method of calculating the power loss in cables in harmonics rich environment is very arduous. The aim of this paper is to present the reasonably accurate method for evaluating effects of harmonics on the power loss in XLPE cables. Computational model is developed in MATLAB for power loss calculation using conventional method. Using this model, calculations are performed for aluminium and copper conductor XLPE cables of different size and type;for three different types of harmonics spectrums having total harmonics distortion (THD) of 30.68%, including all odd harmonics components up to 49th order. Using these results;a mathematical model in the form of simple empirical formula is developed by curve fitting technique. The results obtained by various models are presented and compared with error justification. 展开更多
关键词 Curve Fitting NON-SINUSOIDAL POWER LOSS Per Unit Harmonic Load QUADRATIC POLYNOMIAL Sinusoidal POWER LOSS
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Power System Harmonics Study for Unbalanced Microgrid System with PV Sources and Nonlinear Loads
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作者 Zhanhe Liu Xufeng Xu +1 位作者 Hany A. Abdelsalam Elham Makram 《Journal of Power and Energy Engineering》 2015年第5期43-55,共13页
Harmonics distortion is a crucial problem in microgrid. Harmonic sources can be categorized as two main factors: renewable energy integration and nonlinear loads. Both factors are investigated in this paper. For renew... Harmonics distortion is a crucial problem in microgrid. Harmonic sources can be categorized as two main factors: renewable energy integration and nonlinear loads. Both factors are investigated in this paper. For renewbale energy, photovoltaic (PV) power is one of the most effective solutions for energy crisis and it is showing great potential for serving customers in microgrid. A three- phase PV source model is establised and integrated at different locations in order to observe the impact of harmonics on a microgrid and power quality (PQ). A composite load is modeled using Crossed Frequency Admittance Matrix theory. A practicdal microgrid loacated at GA, USA is used as a study system. The microgrid, PV model and nonlinear load model are simulated in MATLAB/ Simulink environment. The results show the impact of installing PV sources at two types of locations considering linear and composite nonlinear loads. In addition, three PQ indices are discussed to show the numerical impacts with various perspectives. 展开更多
关键词 CROSSED Frequency ADMITTANCE Matrix Nonlinear LOAD harmonics DISTORTION PV Power Quality Indices
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Collinear Libration Points in the Photogravitational CR3BP with Zonal Harmonics and Potential from a Belt
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作者 Jagadish Singh Joel John Taura 《International Journal of Astronomy and Astrophysics》 2015年第3期155-165,共11页
We have studied a reformed type of the classic restricted three-body problem where the bigger primary is radiating and the smaller primary is oblate;and they are encompassed by a homogeneous circular cluster of materi... We have studied a reformed type of the classic restricted three-body problem where the bigger primary is radiating and the smaller primary is oblate;and they are encompassed by a homogeneous circular cluster of material points centered at the mass center of the system (belt). In this dynamical model, we have derived the equations that govern the motion of the infinitesimal mass under the effects of oblateness up to the zonal harmonics J4 of the smaller primary, radiation of the bigger primary and the gravitational potential generated by the belt. Numerically, we have found that, in addition to the three collinear libration points Li (i = 1, 2, 3) in the classic restricted three-body problem, there appear four more collinear points Lni (i = 1, 2, 3, 4). Ln1 and Ln2 result due to the potential from the belt, while Ln3 and Ln4 are consequences of the oblateness up to the zonal harmonics J4 of the smaller primary. Owing to the mutual effect of all the perturbations, L1 and L3 come nearer to the primaries while Ln3 advances away from the primaries;and L2 and Ln1 tend towards the smaller primary whereas Ln2 and Ln4 draw closer to the bigger primary. The collinear libration points Li (i = 1, 2, 3) and Ln2 are linearly unstable whereas the Ln1, Ln3 and Ln4 are linearly stable. A practical application of this model could be the study of motion of a dust particle near a radiating star and an oblate body surrounded by a belt. 展开更多
关键词 Circular RESTRICTED THREE-BODY Problem Photogravitational ZONAL Harmonic Effect POTENTIAL from the BELT
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i<sub>d</sub>-i<sub>q</sub>Control Strategy for Mitigation of Current Harmonics with Fuzzy Logic Controller Using Matlab/Simulation and RTDS Hardware
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作者 Suresh Mikkili Anup Kumar Panda 《Intelligent Control and Automation》 2011年第4期371-382,共12页
The main objective of this paper is to develop Fuzzy controller to analyse the performance of instantaneous real active and reactive current (id-iq) control strategy for extracting reference currents of shunt active f... The main objective of this paper is to develop Fuzzy controller to analyse the performance of instantaneous real active and reactive current (id-iq) control strategy for extracting reference currents of shunt active filters under balanced, un-balanced and balanced non-sinusoidal conditions. When the supply voltages are balanced and sinusoidal, the all control strategies are converge to the same compensation characteristics;However, the supply voltages are distorted and/or un-balanced sinusoidal, these control strategies result in different degrees of compensation in harmonics. The p-q control strategy unable to yield an adequate solution when source voltages are not ideal. Extensive simulations are carried out with Fuzzy controller for id-iq control strategy under different main voltages. The 3-ph 4-wire shunt active filter (SHAF) system is also implemented on a Real Time Digital Simulator (RTDS Hardware) to further verify its effectiveness. The detailed simulation and RTDS Hardware results are included. 展开更多
关键词 Harmonic Compensation SHAF id-iq Control Strategy Fuzzy Controller and RTDS HARDWARE
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Consonance of Complex Tones with Harmonics of Different Intensity 被引量:1
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作者 Antonio Bernini Federico Talamucci 《Open Journal of Acoustics》 2014年第2期78-89,共12页
The starting point of this study is the theory of tonal consonance by Plomp and Levelt. The major reference point is the theory of Critical Band and its use for evaluating consonance of simple tones. On the basis of s... The starting point of this study is the theory of tonal consonance by Plomp and Levelt. The major reference point is the theory of Critical Band and its use for evaluating consonance of simple tones. On the basis of such empirical criterion, our aim consists in providing a method of estimating the value of consonance of complex tones, by taking account not only of the number of harmonics, but also of the intensity of the partials which contribute to forming the tone. By introducing a specific algorithm, the level of consonance of a chord of complex tones is expressed in terms both of frequency differences and sound intensity of the partials. The results give rise to a series of considerations and applications, ranging from displaying the order of consonance of all intervals within the octave up to evaluating the hierarchy of chords in the frame of a musical scale. 展开更多
关键词 CONSONANCE Complex TONES Scale Critical BANDWIDTH INTENSITY of harmonics LOUDNESS
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Lock-in-Amplifier Model for Analyzing the Behavior of Signal Harmonics in Magnetic Particle Imaging 被引量:1
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作者 Kenya Murase Kazuki Shimada 《Open Journal of Applied Sciences》 2018年第5期170-183,共14页
The purpose of this study was to present a lock-in-amplifier model for analyzing the behavior of signal harmonics in magnetic particle imaging (MPI) and some simulation results based on this model. In the lock-in-ampl... The purpose of this study was to present a lock-in-amplifier model for analyzing the behavior of signal harmonics in magnetic particle imaging (MPI) and some simulation results based on this model. In the lock-in-amplifier model, the signal induced by magnetic nanoparticles (MNPs) in a receiving coil was multiplied with a reference signal, and was then fed through a low-pass filter to extract the DC component of the signal (output signal). The MPI signal was defined as the mean of the absolute value of the output signal. The magnetization and particle size distribution of MNPs were assumed to obey the Langevin theory of paramagnetism and a log-normal distribution, respectively, and the strength of the selection magnetic field (SMF) in MPI was assumed to be given by the product of the gradient strength of the SMF and the distance from the field-free region (x). In addition, Gaussian noise was added to the signal induced by MNPs using normally-distributed random numbers. The relationships between the MPI signal and x were calculated for the odd- and even-numbered harmonics and were investigated for various time constants of the low-pass filter used in the lock-in amplifier and particle sizes and their distributions of MNPs. We found that the behavior of the MPI signal largely depended on the time constant of the low-pass filter and the particle size of MNPs. This lock-in-amplifier model will be useful for better understanding, optimizing, and developing MPI, and for designing MNPs appropriate for MPI. 展开更多
关键词 MAGNETIC Particle IMAGING (MPI) Lock-in-Amplifier Model SIGNAL harmonics MAGNETIC Nanoparticles (MNPs)
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Prevalence of metabolic syndrome in type 2 diabetic patients: A comparative study using WHO, NCEP ATP III, IDF and Harmonized definitions
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作者 Mun Chieng Tan Ooi Chuan Ng +3 位作者 Teck Wee Wong Anthony Joseph Yoke Mun Chan Abdul Rahman Hejar 《Health》 2013年第10期1689-1696,共8页
To determine the prevalence of metabolic syndrome (MetS) in Malaysian type 2 diabetic patients using WHO, NCEP ATP III, IDF and the new Harmonized definitions, and the concordance between these definitions. This study... To determine the prevalence of metabolic syndrome (MetS) in Malaysian type 2 diabetic patients using WHO, NCEP ATP III, IDF and the new Harmonized definitions, and the concordance between these definitions. This study involved 313 patients diagnosed with type 2 diabetes mellitus (T2DM) at two Malaysian tertiary hospitals. Socio-demographic data were assessed using a pre-tested interviewer-administered structured questionnaire. Anthropometric measurements were carried out according to standard protocols. Clinical and laboratory characteristics were examined. Kappa (k) statistics were used for the agreement between the four MetS definitions. The overall prevalence rates of MetS (95% CI) were 95.8% (93.6-98.1), 96.1% (94.0-98.3), 84.8% (80.8-88.9) and 97.7% (96.1-99.4) according to the WHO, NCEP ATP III, IDF and the Harmonized definitions, respectively. The Kappa statistics demonstrated a slight to substantial agreement between the definitions (k = 0.179-0.875, p k = 0.875, p hest specificity (100%) in identifying MetS. In conclusion, the new Harmonized criteria established the highest prevalence of MetS among the four definitions applied. There was a very good concordance between the WHO and NCEP ATP III criteria. The extremely high prevalence of MetS observed in type 2 diabetic patients indicates an impending pandemic of CVD risk in Malaysia. Aggressive treatment of MetS components is required to reduce cardiovascular risk in T2DM. 展开更多
关键词 Metabolic Syndrome TYPE 2 DIABETES Mellitus (T2DM) World Health Organization (WHO) Third Report of the National CHOLESTEROL Education Expert Panel on Detection Evaluation Treatment of High Blood CHOLESTEROL in Adults (NCEP ATP III) International DIABETES Federation (IDF) Harmonized Definition
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Maximizing the endosonography: The role of contrast harmonics, elastography and confocal endomicroscopy 被引量:7
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作者 Andrada Seicean Ofelia Mosteanu Radu Seicean 《World Journal of Gastroenterology》 SCIE CAS 2017年第1期25-41,共17页
New technologies in endoscopic ultrasound(EUS) evaluation have been developed because of the need to improve the EUS and EUS-fine needle aspiration(EUS- FNA) diagnostic rate. This paper reviews the principle, indicati... New technologies in endoscopic ultrasound(EUS) evaluation have been developed because of the need to improve the EUS and EUS-fine needle aspiration(EUS- FNA) diagnostic rate. This paper reviews the principle, indications, main literature results, limitations and future expectations for each of the methods presented. Contrast-enhanced harmonic EUS uses a low mechanical index and highlights slowflow vascularization. This technique is useful for differentiating solid and cystic pancreatic lesions and assessing biliary neoplasms, submucosal neoplasms and lymph nodes. It is also useful for the discrimination of pancreatic masses based on their qualitative patterns; however, the quantitative assessment needs to be improved. The detection of small solid lesions is better, and the EUS-FNA guidance needs further research. The differentiation of cystic lesions of the pancreas and the identification of the associated malignancy features represent the main indications. Elastography is used to assess tissue hardness based on the measurement of elasticity. Despite its low negative predictive value, elastography might rule out the diagnosis of malignancy for pancreatic masses. Needle confocal laser endomicroscopy offers useful information about cystic lesions of the pancreas and is still under evaluation for use with solid pancreatic lesions of lymph nodes. 展开更多
关键词 ENDOSONOGRAPHY Endosonography-fine needle aspiration CONTRAST-ENHANCED harmonics ELASTOGRAPHY ENDOMICROSCOPY Pancreas Lymph nodes Cyst
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New-type Wound-rotor asynchronous motors Started by harmonics
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作者 Xu Shizhang Huazhong University of Science and Technology Jiang Huacheng 《Electricity》 1992年第2期53-56,共4页
Ⅰ. Preface Starting is one of the important topics of asynchronous mo-tors. Varied methods over a long period of time for improving thestarting characteristics of the asynchronous motors had beenadopted by domestic a... Ⅰ. Preface Starting is one of the important topics of asynchronous mo-tors. Varied methods over a long period of time for improving thestarting characteristics of the asynchronous motors had beenadopted by domestic and foreign electrical engineers. The methodswhich innovate on the internal structure of the electrical motors soas to improve the starting characteristics fall into two kinds. The firstone is to change the structure of the stator winding of the motors, forinstance, the "star-delta" starting, the "prolonged side triangle" 展开更多
关键词 asynchronous harmonics WINDING TRIANGLE STATOR STARTING rotor delta running connected
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An Improved Chirplet Transform and Its Application for Harmonics Detection 被引量:1
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作者 Guo-Sheng Hu Feng-Feng Zhu 《Circuits and Systems》 2011年第3期107-111,共5页
The chirplet transform is the generalization form of fast Fourier transform , short-time Fourier transform, and wavelet transform. It has the most flexible time frequency window and successfully used in practices. How... The chirplet transform is the generalization form of fast Fourier transform , short-time Fourier transform, and wavelet transform. It has the most flexible time frequency window and successfully used in practices. However, the chirplet transform has not inherent inverse transform, and can not overcome the signal reconstructing problem. In this paper, we proposed the improved chirplet transform (ICT) and constructed the inverse ICT. Finally, by simulating the harmonic voltages, The power of the improved chirplet transform are illustrated for harmonic detection. The contours clearly showed the harmonic occurrence time and harmonic duration. 展开更多
关键词 harmonics IMPROVED CHIRPLET Transform (ICT) S-TRANSFORM TIME-FREQUENCY Representation (TFR)
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NEW THREE PHASE VFVA SINE WAVE GENERATOR AND PWM HARMONICS ANALYSIS
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作者 林棋 《Journal of Electronics(China)》 1994年第1期79-87,共9页
The new three phase VFVA sine wave generator is presented in this paper. A new sampling holding three phase VFVA sine wave generator’s principle, circuit and experimentation waveform are introduced. The principle of ... The new three phase VFVA sine wave generator is presented in this paper. A new sampling holding three phase VFVA sine wave generator’s principle, circuit and experimentation waveform are introduced. The principle of this sampling holding circuit is simple and the realization of har’dware circuit is easy. Here we describe the three phase reference sine wave which is produced by this generator’s circuit and is required by PWM inverter is described in this paper, and also introduced the speed control and harmonir analysis of PWM inverter variable frequency. 展开更多
关键词 SINE WAVE GENERATOR harmonics analysis THREE phase VFVA
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Interference of harmonics emitted by different tunneling momentum channels in laser fields
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作者 Ling-Yu Zhang Zhuo-Xuan Xie +2 位作者 Can Wang Xin-Lei Ge Jing Guo 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期366-372,共7页
By numerically solving the semiconductor Bloch equation(SBEs),we theoretically study the high-harmonic generation of ZnO crystals driven by one-color and two-color intense laser pulses.The results show the enhancement... By numerically solving the semiconductor Bloch equation(SBEs),we theoretically study the high-harmonic generation of ZnO crystals driven by one-color and two-color intense laser pulses.The results show the enhancement of harmonics and the cut-off remains the same in the two-color field,which can be explained by the recollision trajectories and electron excitation from multi-channels.Based on the quantum path analysis,we investigate contribution of different ranges of the crystal momentum k of ZnO to the harmonic yield,and find that in two-color laser fields,the intensity of the harmonic yield of different ranges from the crystal momentum makes a big difference and the harmonic intensity is depressed from all k channels,which is related to the interferences between harmonics from symmetric k channels. 展开更多
关键词 high-order harmonic generation the semiconductor Bloch equation k-resolvedinter-bandhar-monic spectrum four-step semiclassical model
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Distorted Waveform Balancing Using an Artificial Bee Colony (ABC) Based Optimal Control for Mitigating Total Harmonics in Single Phase Inverter
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作者 N. M. Spencer Prathap Singh Kesavan Nair T. Ajith Bosco Raj 《Circuits and Systems》 2016年第9期2154-2167,共14页
The main objective of this paper is to reduce the total harmonics in a single phase voltage source inverter using Artificial Bee Colony (ABC) optimization technique for critical load applications. Single phase inverte... The main objective of this paper is to reduce the total harmonics in a single phase voltage source inverter using Artificial Bee Colony (ABC) optimization technique for critical load applications. Single phase inverter is a non-linear load using power electronic components causing distortions in the load voltage and current wave patterns from the sinusoidal waveforms due to harmonics. The mapping state space model for a full bridge voltage source inverter was developed using output load resistance. An optimal ABC technique has been designed and optimized values are estimated using a full bridge voltage controlled inverter using Proportional Integral Algorithm. The MATLAB/SIMULINK tool and Experimental setup were implemented and their THD values were estimated. Also this ABC scheme is compared with the previous results such as PI Algorithm, Fuzzy logic controller and Neuro-fuzzy controllers. From the simulation and experimental results using ABC algorithm, it is observed that the total harmonics are mitigated considerably compared to previous results with respect to the power quality standards such as IEEE-519 and IEC 61000. 展开更多
关键词 Voltage Source Inverter THD Proportional Integral Controller Artificial Bee Colony Voltage harmonics Current harmonics
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Selection of right-circular-polarized harmonics from p orbital of neon atom by two-color bicircular laser fields 被引量:1
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作者 Chang-Long Xia Yue-Yue Lan +1 位作者 Qian-Qian Li Xiang-Yang Miao 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期315-320,共6页
The polarization properties of high-order harmonic generation(HHG) in the two-color circularly polarized laser fields are investigated by numerically solving the two-dimensional time-dependent Schr?dinger equation. By... The polarization properties of high-order harmonic generation(HHG) in the two-color circularly polarized laser fields are investigated by numerically solving the two-dimensional time-dependent Schr?dinger equation. By adding a wavelength of 1600-nm right-circular-polarized field to an 800-nm left-circular-polarized field, HHG is simulated from a real model of neon atom with p orbital, but not from a hydrogen-like atom model with s orbital. The orders of 3n + 1 can be selected while the orders of 3n + 2 are suppressed by adjusting the intensities of the two pulses. The physical mechanism is analyzed by time-frequency analysis and semiclassical model. 展开更多
关键词 HIGH-ORDER harmonic generation CIRCULAR POLARIZATION field POLARIZATION SELECTION
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Phase Relation of Harmonics in Nonlinear Focused Ultrasound 被引量:3
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作者 彭哲凡 林伟军 +3 位作者 刘石磊 苏畅 张海澜 王秀明 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第8期54-58,共5页
The phase relation of harmonics in high-intensity focused ultrasound is investigated numerically and experimen- tally. The nonlinear Westervelt equation is solved to model nonlinear focused sound field by using the fi... The phase relation of harmonics in high-intensity focused ultrasound is investigated numerically and experimen- tally. The nonlinear Westervelt equation is solved to model nonlinear focused sound field by using the finite difference time domain method. Experimental waveforms are measured by a robust needle hydrophone. Then the relative phase quantity is introduced and obtained by using the zero-phase filter. The results show that the nth harmonic relative phase quantity is approximately (n - 1) π/3 at geometric center and increases along the axial direction. Moreover, the relative phase quantity decreases with the increase of source amplitude. This phase relation gives an explanation of some nonlinear phenomena such as the discrepancy of positive and negative pressure. 展开更多
关键词 of on AS Phase Relation of harmonics in Nonlinear Focused Ultrasound IS in
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