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“整”从“桩”来 被引量:1
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作者 王潇 《中华武术》 2003年第8期34-34,共1页
何为“整”?就是铜浇铁铸,浑然一体。对于一个习武之人来说,“整”是一个最基本的要求,不要以为它是基础就不重视它,因为最基础的东西也是最高级的东西。尤其是内家拳的习练者,如果没有练“整”就进行更高级的训练,到最后是什么都练不... 何为“整”?就是铜浇铁铸,浑然一体。对于一个习武之人来说,“整”是一个最基本的要求,不要以为它是基础就不重视它,因为最基础的东西也是最高级的东西。尤其是内家拳的习练者,如果没有练“整”就进行更高级的训练,到最后是什么都练不出来的。感觉练得不错,可是一遇上高手,总是这样的人一败涂地,究其原因,就是因为不“整”,确切的说就是桩站得不够,或是站得不对,更有甚者是根本就没站过桩。 笔者经常去书店阅读武学典籍,购买武术刊物,也时常与各门派交流。 展开更多
关键词 内家拳 “整”力 站桩 呼吸方法 技击训练
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SURFACE CHARACTERISTICS OF 10Ni3MnCuAl STEEL BY SHOT PEENING 被引量:7
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作者 缪宏 左敦稳 +1 位作者 王红军 汪洪峰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第3期178-183,共6页
The surface of grinding 10Ni3MnCuAl steel is processed by the shot peening with different intensities. After shot peening, the metallographic structure of 10Ni3MnCuAl steel and the micro-structure on the surface layer... The surface of grinding 10Ni3MnCuAl steel is processed by the shot peening with different intensities. After shot peening, the metallographic structure of 10Ni3MnCuAl steel and the micro-structure on the surface layer are analyzed. The micro-hardness in the shot peening affected layer and the residual pressure stress are surveyed. The changes of surface quality, such as micro-hardness, metallographic structure and residual stress caused by shot peening are investigated. The result shows that shot peening can significantly improve surface quality and fatigue life of 10Ni3MnCuAl steel. The over peening effect is produced when the shot peening intensity is high, and it leads to the decrease of the fatigue life. When the optimal arc high value of shot peening is 0. 40 mm in experiments, the best surface quality is obtained and the depth of the residual stress in the precipitation-hardening layer reaches 450μm. 展开更多
关键词 shot peening surface properties residual stress over peening
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FREE VIBRATION ANALYSIS OF SHEAR WALLS WITH SHORT PIERS 被引量:1
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作者 黄东升 刘世美 +2 位作者 华新钰 刘俊龙 艾军 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第3期194-201,共8页
The equations of the lateral deflection curve of the short pier shear wall under a lateral concentrated load at any level are derived by employing a continuous approach. Lateral flexibility matrixes for the dynamic an... The equations of the lateral deflection curve of the short pier shear wall under a lateral concentrated load at any level are derived by employing a continuous approach. Lateral flexibility matrixes for the dynamic analysis are also obtained by repeatedly calculating the lateral unit load on the wall at each level where a lumped mass located. Dynamic analyses are implemented for short pier shear walls with different parameters, called the integrative coefficient and the pier strength coefficient related to the dimensions of walls. The influences of two coefficients on the dynamic performances of the structure are studied. Results indicate that with the increase of the integrative coefficient, the periods of top two modes apparently decrease but the other periods of higher frequency modes show little variation when the pier strength coefficient remains constant. Similarly, if the integrative coefficient is constant, the top two periods of the free vibration decrease with the increase of the integrative coefficient but the other periods of higher frequency modes show less variation. 展开更多
关键词 shear wall with short piers dynamic analysis integrative coefficient pier strength coefficient
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On the Lie Symmetries of the NonholonomicMechanical Systems 被引量:2
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作者 吴润衡 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1997年第3期229-235,共7页
The Lie symmetries of nonholonomic mechanical systems are corsidered. Some defmi tions and criteria on the Lie symmetries, and the conservation laws of the systems are given.And some examples to illustrate the applic... The Lie symmetries of nonholonomic mechanical systems are corsidered. Some defmi tions and criteria on the Lie symmetries, and the conservation laws of the systems are given.And some examples to illustrate the application of the results are provided. 展开更多
关键词 analytical mechanics nonholonomic system Lie symmetry conservation las
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Algebraic Structure of the Dynamical Equations of Holonomic Mechanical System in Relative Motion 被引量:2
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作者 张毅 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1998年第1期12-18,共7页
Aim To study an algebraic of the dynamical equations of holonomic mechanical systems in relative motion. Methods The equations of motion were presented in a contravariant algebraic form and an algebraic product was... Aim To study an algebraic of the dynamical equations of holonomic mechanical systems in relative motion. Methods The equations of motion were presented in a contravariant algebraic form and an algebraic product was determined. Results and Conclusion The equations a Lie algebraic structure if any nonpotential generalized force doesn't exist while while the equations possess a Lie-admissible algebraic structure if nonpotential generalized forces exist . 展开更多
关键词 analytical mechanics holonomic system relative motion Lie-admissible algebra
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Poisson's Theory of the Chaplygin's Equations 被引量:1
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作者 梅凤翔 史荣昌 张永发 《Journal of Beijing Institute of Technology》 EI CAS 1995年第2期129+123-129,共8页
Puts forward an algebraic structure of the Chaplygin's equations of nonholonomic systems, establish the Poisson's theory of the integration equations and gives an example for illustrating the application of th... Puts forward an algebraic structure of the Chaplygin's equations of nonholonomic systems, establish the Poisson's theory of the integration equations and gives an example for illustrating the application of the result. 展开更多
关键词 analytical mechanics algebra/nonholonomic system
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Study on the Feasibility of the Calculation Methods of Consolidating Rural Residential Land into Arable Land in China
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作者 何英彬 陈佑启 +2 位作者 姚艳敏 许新国 李志斌 《Journal of Landscape Research》 2009年第9期55-58,共4页
Since the increasing demand for arable land and low efficient and disordered use of rural residential land,land consolidation for rural settlement has become a hot issue in China.Many Chinese scientists studied the to... Since the increasing demand for arable land and low efficient and disordered use of rural residential land,land consolidation for rural settlement has become a hot issue in China.Many Chinese scientists studied the topic from different angles.However,there is no reference systematically summarizing and discussing feasibility of consolidating rural residential land into arable land.The authors listed and analyzed the calculation methods of consolidating rural residential land into arable land,and discussed the feasibility and reasonability of those methods.Moreover,this paper put forward the study orientation in this regard for providing references for relevant researches. 展开更多
关键词 Rural residential land Land consolidation METHODOLOGY POTENTIALITY FEASIBILITY
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Financial Strategy during Power System Restructuring
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作者 吴志勇 《Electricity》 2001年第2期9-10,共2页
Aiming at the problems of power structure irrationality, lagging of power network behind power source development and high proportion of overdone and small sized units existing currently in power system in China, fina... Aiming at the problems of power structure irrationality, lagging of power network behind power source development and high proportion of overdone and small sized units existing currently in power system in China, financial and running strategies are set forth corresponding to power system restructuring. 展开更多
关键词 financial strategy power system restructuring
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Perturbation and Adiabatic Invariants of Mei Symmetry for Nonholonomic Mechanical Systems 被引量:2
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作者 DING Ning FANG Jian-Hui WANG Peng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第4期594-596,共3页
Based on the concept of adiabatic invariant, the perturbation and adiabatic invariants of the Mei symmetry for nonholonomic mechanical systems are studied. The exact invariants of the Mei symmetry for the system witho... Based on the concept of adiabatic invariant, the perturbation and adiabatic invariants of the Mei symmetry for nonholonomic mechanical systems are studied. The exact invariants of the Mei symmetry for the system without perturbation are given. The perturbation to the Mei symmetry is discussed and the adiabatic invariants of the Mei symmetry for the perturbed system are obtained. 展开更多
关键词 Mei symmetry PERTURBATION adiabatic invariant nonholonomic mechanical system
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Kinetic Study on CO_2 Reforming of Methane 被引量:5
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作者 C.E.Quincoces M.G.González 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第2期190-195,共6页
The kinetics of CO2 reforming of methane has been studied at 976-1033K on a commercial NiO/CaO/Al2O3 catalyst in a packed-bed continuous reactor. The reaction was carried out at atmospheric pressure and CO2/CH4 ratio... The kinetics of CO2 reforming of methane has been studied at 976-1033K on a commercial NiO/CaO/Al2O3 catalyst in a packed-bed continuous reactor. The reaction was carried out at atmospheric pressure and CO2/CH4 ratio > 2. The Hougen-Watson rate models were fitted to experimental data assuming the disso ciative adsorption of methane as the rate-determining step. The reaction rate showed an effective reaction order of about unity for CH4. The apparent activity energy was found to be 104 kJ·mol-1. Therefore the kinetic reaction parameters were determined and a possible reaction mechanism was proposed. 展开更多
关键词 CH4 reforming Ni catalysts SYNGAS
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Perturbation to Symmetries and Adiabatic Invariants of Nonholonomic Dynamical System of Relative Motion 被引量:1
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作者 CHENXiang-Wei WANGMing-Quan WANGXin-Min 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4期577-581,共5页
Based on the theory of symmetries and conserved quantities, the exact invariants and adiabatic invariants of nonholonomic dynamical system of relative motion are studied. The perturbation to symmetries for the nonholo... Based on the theory of symmetries and conserved quantities, the exact invariants and adiabatic invariants of nonholonomic dynamical system of relative motion are studied. The perturbation to symmetries for the nonholonomic dynamical system of relative motion under small excitation is discussed. The concept of high-order adiabatic invariant is presented, and the form of exact invariants and adiabatic invariants as well as the conditions for their existence are given. Then the corresponding inverse problem is studied. 展开更多
关键词 nonholonomic dynamical system of relative motion PERTURBATION exactinvariant adiabatic invariant
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Integrating Factors and Conservation Theorems of Nonholonomic Dynamical System of Relative Motion 被引量:2
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作者 QIAO Yong-Fen ZHAO Shu-Hong LI Ren-Jie 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期217-220,共4页
The integrating factors and conservation theorems of nonholonomic dynamical system of relative motion are studied. First, the dynamical equations of relative motion of system are written. Next, the definition of integ... The integrating factors and conservation theorems of nonholonomic dynamical system of relative motion are studied. First, the dynamical equations of relative motion of system are written. Next, the definition of integrating factors is given, and the necessary conditions for the existence of the conserved quantities are studied in detail. Then, the conservation theorem and its inverse of system are established. Finally, an example is given to illustrate the application of the result. 展开更多
关键词 nonholonomic system relative motion integrating factor conservation theorem
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Perturbation to Noether-Mei Symmetry and Adiabatic Invariants for Nonholonomic Mechanical Systems in Phase Space 被引量:1
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作者 ZHANG Ming-Jiang FANG Jian-Hui LU Kai 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第4期600-604,共5页
Based on the concept of adiabatic invariant, the perturbation to Noether Mei symmetry and adiabatic invariants for nonholonomie mechanical systems in phase space are studied. The definition of the perturbation to Noet... Based on the concept of adiabatic invariant, the perturbation to Noether Mei symmetry and adiabatic invariants for nonholonomie mechanical systems in phase space are studied. The definition of the perturbation to Noether-Mei symmetry for the system is presented, and the criterion of the perturbation to Noether-Mei symmetry is given. Meanwhile, the Noether adiabatic invariants and the Mei adiabatic invariants for the perturbed system are obtained. 展开更多
关键词 Noether-Mei symmetry PERTURBATION adiabatic invariant nonholonomic mechanical system phase space
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Kinetic model on coke oven gas with steam reforming 被引量:1
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作者 张家元 周孑民 闫红杰 《Journal of Central South University of Technology》 EI 2008年第1期127-131,共5页
The effects of factors such as the molar ratio of H2O to CH4 (n(H2O)/n(CH4)), methane conversion temperature and time on methane conversion rate were investigated to build kinetic model for reforming of coke-oven gas ... The effects of factors such as the molar ratio of H2O to CH4 (n(H2O)/n(CH4)), methane conversion temperature and time on methane conversion rate were investigated to build kinetic model for reforming of coke-oven gas with steam. The results of experiments show that the optimal conditions for methane conversion are that the molar ratio of H2O to CH4 varies from 1.1 to 1.3 and the conversion temperature varies from 1 223 to 1 273 K. The methane conversion rate is more than 95% when the molar ratio of H2O to CH4 is 1.2, the conversion temperature is above 1 223 K and the conversion time is longer than 0.75 s. Kinetic model of methane conversion was proposed. All results demonstrate that the calculated values by the kinetic model accord with the experimental data well, and the error is less than 1.5%. 展开更多
关键词 coke oven gas steam reforming kinetic model conversion rate
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Analysis of an Epidemic Model with Age of Vaccination 被引量:2
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作者 GUO Shu-li DING Feng-xia 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第4期545-552,共8页
A simple SI epidemic model with age of vaccination is discussed in this paper.Both vexing birth rate, the mortality rate caused by disease and vaccine waning rate areconsidered in this model. We prove that the global ... A simple SI epidemic model with age of vaccination is discussed in this paper.Both vexing birth rate, the mortality rate caused by disease and vaccine waning rate areconsidered in this model. We prove that the global dynamics is completely determined bythe basic reproductive number R(ψ)(ψ denotes per capita vaccination rate). If R(0) 〈 1,the disease-free equilibrium is a global attractor; If R(ψ) 〈: 1, the disease-free equilibriumis locally asymptotically stable; If R(ψ) :〉 1, an unique endemic equilibrium exists and islocally asymptotically stable under certain condition. 展开更多
关键词 SI model VACCINATION EQUILIBRIUM STABILITY
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OBSERVATIONAL STUDY OF MESO-β WAVE IN LOW LATITUDES OF SOUTH CHINA SEA OVER THE SUMMER MONSOON 被引量:1
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作者 余欲晓 刘正奇 《Journal of Tropical Meteorology》 SCIE 2002年第1期104-112,共9页
The intensive observation data of the Nansha Islands are used to study and discuss the meso-and fine-scale systems existing with large-scale monsoon circulation during the onset of the southwesterly monsoon in the low... The intensive observation data of the Nansha Islands are used to study and discuss the meso-and fine-scale systems existing with large-scale monsoon circulation during the onset of the southwesterly monsoon in the low-latitude areas of the South China Sea. Effects of low-latitude tropical meso-scale gravity waves on weather have been disclosed. The generation and transportation of the local meso-scale gravity wave have been preliminarily studied from the viewpoint of dynamics. 展开更多
关键词 meso-β scale geostrophic adjustment gravity wave
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Some Physiological Responses of Chinese Iris to Salt Stress 被引量:7
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作者 BAI Wen-Bo LI Pin-Fang +2 位作者 LI Bao-Guo H. FUJIYAMA FAN Fen-Cheng 《Pedosphere》 SCIE CAS CSCD 2008年第4期454-463,共10页
Chinese iris (Iris lactea Pall. var. chinensis (Fisch) Koidz.), a robust iridaceous plant, is widespread in arid and semiarid regions with high salinity. However, the mechanism of its salt tolerance is not well un... Chinese iris (Iris lactea Pall. var. chinensis (Fisch) Koidz.), a robust iridaceous plant, is widespread in arid and semiarid regions with high salinity. However, the mechanism of its salt tolerance is not well understood. In this study, plant growth, water status, content and distribution of inorganic ions, cell membrane permeability, and proline content of I. laetea under salt stress were investigated using nutrient solutions with six NaCl concentrations ranging from 0 to 350 mmol L^-1. The results indicated that the biomass, height, fresh weight, K^+ content, and K^+/Na^+ and Ca^2+/Na^+ ratios decreased with increasing NaCl stress, whereas plant water deficit and contents of Na^+ and Cl- increased with increasing NaCl stress. In all salt treatments, water deficit of shoots was found to be higher than that of roots and had a positive correlation with salt concentration. When the NaCl concentration was less than 280 mmol L^-1, the ion absorption selectivity ratio and the transportation selectivity ratio sharply increased with increasing NaCl stress. Under medium salt stress, I. lactea exhibited a strong K^+ selective absorption and the transportation of K^+ from roots to shoots increased, whereas Na^+ was not transported and was mostly retained in roots. The plants were able to maintain osmotic adjustment through the accumulation of Na^+, Cl-, and proline. On the basis of its biomass production under salt stress, I. lactea could be considered as a facultative halophyte. 展开更多
关键词 inorganic ion Iris lactea Pall. var. chinensis (Fisch) Koidz. NaCl stress osmotic adjustment
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A risk-based methodology for the optimal placement of hazardous gas detectors 被引量:4
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作者 Kang Cen Ting Yao +1 位作者 Qingsheng Wang Shengyong Xiong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第5期1078-1086,共9页
Hazardous gas detection systems play an important role in preventing catastrophic gas-related accidents in process industries. Even though effective detection technology currently exists for hazardous gas releases and... Hazardous gas detection systems play an important role in preventing catastrophic gas-related accidents in process industries. Even though effective detection technology currently exists for hazardous gas releases and a majority of process installations have a large number of sensitive detectors in place, the actual operating performance of gas detection systems still does not meet the expected requirements. In this paper, a riskbased methodology is proposed to optimize the placement of hazardous gas detectors. The methodology includes three main steps, namely, the establishment of representative leak scenarios, computational fluid dynamics(CFD)-based gas dispersion modeling, and the establishment of an optimized solution. Based on the combination of gas leak probability and joint distribution probability of wind velocity and wind direction, a quantitative filtering approach is presented to select representative leak scenarios from all potential scenarios. The commercial code ANSYS-FLUENT is used to estimate the consequence of hazardous gas dispersions under various leak and environmental conditions. A stochastic mixed-integer linear programming formulation with the objective of minimizing the total leak risk across all representative leak scenarios is proposed, and the greedy dropping heuristic algorithm(GDHA) is used to solve the optimization model. Finally, a practical application of the methodology is performed to validate its effectiveness for the optimal design of a gas detector system in a high-sulfur natural gas purification plant in Chongqing, China. The results show that an appropriate number of gas detectors with optimal cost-effectiveness can be obtained, and the total leak risk across all potential scenarios can be substantially reduced. This methodology provides an effective approach to guide the optimal placement of pointtype gas detection systems involved with either single or mixed gas releases. 展开更多
关键词 Leak scenario Leak risk Gas detection Detector placement Mixed-integer linear programming
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Two New Types of Conserved Quantities Deduced from Noether Symmetry for Nonholonomic Mechanical System
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作者 ZHANG Xiao-Ni FANG Jian-Hui PANG Ting LIN Peng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第2期205-208,共4页
For a nonholonomic mechanical system, the generalized Mei conserved quantity and the new generalized Hojman conserved quantity deduced from Noether symmetry of the system are studied. The criterion equation of the Noe... For a nonholonomic mechanical system, the generalized Mei conserved quantity and the new generalized Hojman conserved quantity deduced from Noether symmetry of the system are studied. The criterion equation of the Noether symmetry for the system is got. The conditions under which the Noether symmetry can lead to the two new conserved quantities are presented and the forms of the conserved quantities are obtained. Finally, an example is given to illustrate the application of the results. 展开更多
关键词 Noether symmetry conserved quantity nonholonomic mechanical system
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Simulation and reliability analysis of shunt active power filter based on instantaneous reactive power theory 被引量:1
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作者 CUI Yu-long LIU Hong +1 位作者 WANG Jing-qin SUN Shu-guang 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第3期416-421,共6页
This paper first discusses the operating principle of instantaneous reactive power theory. Then, the theory is introduced into shunt active power filter and its control scheme is studied. Finally, Matlab/Simulink powe... This paper first discusses the operating principle of instantaneous reactive power theory. Then, the theory is introduced into shunt active power filter and its control scheme is studied. Finally, Matlab/Simulink power system toolbox is used to simulate the system. In the simulation model, as the most common harmonic source, 3-phase thyristor bridge rectifier circuit is constructed. The simulation results before and after the shunt active filter was switched to the system corresponding to different firing angles of the thyristors are presented and analyzed, which demonstrate the practicability and reliability of the proposed shunt active filter scheme. 展开更多
关键词 Shunt active filter Instantaneous reactive power theory HARMONIC 3-phase thyristor bridge rectifier Matlab/ Simulink
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