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Clinical Study on the Treatment of Diabetic Retinopathy(Qi-Yin Deficiency Type)with the Method of Soothing the Liver,Harmonizing the Spleen,and Opening the Orifices
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作者 Yu Jiang Ling Li Guang Han 《Journal of Clinical and Nursing Research》 2025年第8期14-20,共7页
Objective:To observe the clinical efficacy of the method of softening the liver,harmonizing the spleen,and unblocking the orifices in the treatment of Xiaoke Neizhang with Qi and Yin deficiency type.Methods:Seventy-tw... Objective:To observe the clinical efficacy of the method of softening the liver,harmonizing the spleen,and unblocking the orifices in the treatment of Xiaoke Neizhang with Qi and Yin deficiency type.Methods:Seventy-two patients with Xiaoke Neizhang of qi and yin deficiency type were selected from March 2024 to May 2025 and divided into a treatment group and a control group with 36 cases each according to the random number table method.The treatment group was treated with the method of softening the liver,harmonizing the spleen,and unblocking the orifices,which included oral administration of Softening the Liver and Harmonizing the Spleen Pills combined with iontophoresis of Xuesaitong Injection.The control group was treated with oral administration of calcium dobesilate capsules.Both groups were treated for 2 courses,and multiple indicators such as visual acuity,fundus condition,and TCM syndrome scores were compared between the two groups.Results:The total effective rate of the treatment group was higher than that of the control group.There were significant differences in visual acuity,fundus condition,and TCM syndrome scores between and within the groups(P<0.05).Conclusion:The method of softening the liver,harmonizing the spleen,and unblocking the orifices has a definite clinical effect in the treatment of Xiaoke Neizhang with Qi and Yin deficiency type.It has a direct effect,is painless,easy for patients to accept,and has high clinical application value. 展开更多
关键词 Softening the Liver and harmonizing the Spleen Pills Xuesaitong injection IONTOPHORESIS Xiaoke Neizhang Qi and Yin deficiency type
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Summary of professor GAO Yu-chun's experience of “harmonizing the spleen and stomach”acupuncture technique 被引量:6
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作者 刘威萍 李朋朋 +2 位作者 韩一栩 邢潇 王艳君 《World Journal of Acupuncture-Moxibustion》 CSCD 2017年第1期67-73,共7页
The spleen and stomach are the foundation of acquired constitution, and the source of qi and blood production. Therefore, harmonizing the spleen and stomach is of great importance in treatment of diseases. In this pap... The spleen and stomach are the foundation of acquired constitution, and the source of qi and blood production. Therefore, harmonizing the spleen and stomach is of great importance in treatment of diseases. In this paper, based on GAO's academic ideas of acupuncture and moxibustion, the different rules of harmonizing the spleen and stomach for internal miscellaneous diseases and carefully supplementing spleen and stomach for externally-contracted diseases were elaborated by starting with the acupoint selection prescriptions and harmonizing the spleen and stomach. In addition, time acupuncture and pattern differentiation moxibustion application and other treatment characteristics were put forward. The experience of professor GAO Yu-chun in acupuncture manipulation of "harmonizing the spleen and stomach" was summarized in detail from five aspects for learning and reference. 展开更多
关键词 GAO Yu-chun harmonize the spleen and stomach acupuncturemanipulation EXPERIENCE
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Professor Ruixia Pei's Clinical Experience in Treating Globus Hystericus with"Harmonizing Method" 被引量:1
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作者 Di Sun Ruixia Pei +1 位作者 Xingyu Chen Fen Zhang 《Journal of Clinical and Nursing Research》 2021年第5期51-53,共3页
To summarize professor Pei9s experience in treating globus hystericus.Methods:Learn from your teacher.Results:Professor Pei had been suffering from the disease for more than 30 years and had her unique views on the tr... To summarize professor Pei9s experience in treating globus hystericus.Methods:Learn from your teacher.Results:Professor Pei had been suffering from the disease for more than 30 years and had her unique views on the treatment of globus hystericus,which are mostly for emotional dysfunction,liver Qi is not comfortable,functioning of Qi is not adjusted,Yin and Yang imbalance.The basic principle of treatment is to grasp the core pathogenesis,take harmony as the method and balance as the duration,harmonize Qi,regulate Yin and Yang,use drugs to disperse the liver and rectify Qi,as well as auxiliary treatment with products to promote blood circulation,remove blood stasis,dryness and dampness,and clear heat. 展开更多
关键词 Professor Ruixia Pei harmonizing method Globus hystericus Case reports
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Clinical Experience of"'Harmonizing MethodM based on Usage of Minor Bupleurum Decoction
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作者 Shuanglong Ji Jiayong Zhang 《Journal of Clinical and Nursing Research》 2021年第5期47-50,共4页
Minor Bupleurum Decoction is a common TCM compound and a classic prescription that can best reflect the"harmonizing method',of TCM.But there are many differences on the usage and dosage of Minor Bupleurum Dec... Minor Bupleurum Decoction is a common TCM compound and a classic prescription that can best reflect the"harmonizing method',of TCM.But there are many differences on the usage and dosage of Minor Bupleurum Decoction.Combined with the clinical treatment experience,this paper summarizes the experience of Minor Bupleurum Decoction in the clinical treatment of diseases.It is hoped that relevant suggestions can be provided for clinicians to improve the clinical therapeutic effect of Minor Bupleurum Decoction. 展开更多
关键词 Minor Bupleurum Decoction harmonizing method Lesser Yang disease
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Petahertz communication:Harmonizing optical spectra for wireless communications 被引量:1
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作者 Zhengyuan Xu Weijie Liu +1 位作者 Zhaocheng Wang Lajos Hanzo 《Digital Communications and Networks》 SCIE CSCD 2021年第4期605-614,共10页
With the rapid deployment of Next-Generation Networks(NGN),the research community has initiated discussions on an entirely new suite of optical enabling techniques.To pave the way for the development of future wireles... With the rapid deployment of Next-Generation Networks(NGN),the research community has initiated discussions on an entirely new suite of optical enabling techniques.To pave the way for the development of future wireless networks,this article aims to unify the existing infrared,visible light,and ultraviolet subbands while also exploring the potential of the Petahertz(PHz)band to support extremely bandwidth-thirsfy telepresence style applications.Our focus is on the emerging Petahertz Communication(PetaCom)framework,scenario-dependent propagation channels,modulation schemes,system performance,multiple access techniques,and networking.We conclude with a range of PetaCom challenges and open research issues. 展开更多
关键词 Petahertz communication Petahertz spectrum harmonization Optical spectrum Optical wireless communication
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Nigeria's Efforts in Harmonizing Tax Laws for Greater Certainty
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作者 Chidi Barry Chukwu 《Belt and Road Initiative Tax Journal》 2024年第2期24-33,共10页
This paper highlights Nigeria's efforts in harmonizing tax laws in order to achieve greater certainty in its tax system.The research examines the current tax landscape in Nigeria,pointing out the complexities and ... This paper highlights Nigeria's efforts in harmonizing tax laws in order to achieve greater certainty in its tax system.The research examines the current tax landscape in Nigeria,pointing out the complexities and inconsistencies that have hindered tax administration and compliance.This article also emphasizes the initia-tives undertaken by the Nigerian government to harmonize tax laws,including the establishment of the National Tax Policy and the review of existing tax legislation.The impact of these efforts on tax certainty is highlighted,and areas for further improvement are identified.The research findings suggest that,while progress has been made,more needs to be done to achieve a cohesive and coherent tax system that promotes economic growth and development.This article recommends a com-prehensive approach to tax reform,involving stakeholder engagement,legislative simplification and the adoption of international best practices. 展开更多
关键词 Tax certainty Tax harmonization Transparency in tax administration Global standards Tax reform
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Sensitivity analysis of the lithospheric magnetic field at satellite altitude:the effects of the inducing field and the shape of the magnetic lithosphere 被引量:1
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作者 JinSong Du YuKun Li +5 位作者 HouPu Li ChangQing Yuan KangAn Zhao JiangSong Gui Pan Zhang ShaoFeng Bian 《Earth and Planetary Physics》 2025年第3期642-652,共11页
As a means of quantitative interpretation,forward calculations of the global lithospheric magnetic field in the Spherical Harmonic(SH)domain have been widely used to reveal geophysical,lithological,and geothermal vari... As a means of quantitative interpretation,forward calculations of the global lithospheric magnetic field in the Spherical Harmonic(SH)domain have been widely used to reveal geophysical,lithological,and geothermal variations in the lithosphere.Traditional approaches either do not consider the non-axial dipolar terms of the inducing field and its radial variation or do so by means of complicated formulae.Moreover,existing methods treat the magnetic lithosphere either as an infinitesimally thin layer or as a radially uniform spherical shell of constant thickness.Here,we present alternative forward formulae that account for an arbitrarily high maximum degree of the inducing field and for a magnetic lithosphere of variable thickness.Our simulations based on these formulae suggest that the satellite magnetic anomaly field is sensitive to the non-axial dipolar terms of the inducing field but not to its radial variation.Therefore,in forward and inverse calculations of satellite magnetic anomaly data,the non-axial dipolar terms of the inducing field should not be ignored.Furthermore,our results show that the satellite magnetic anomaly field is sensitive to variability in the lateral thickness of the magnetized shell.In particular,we show that for a given vertically integrated susceptibility distribution,underestimating the thickness of the magnetic layer overestimates the induced magnetic field.This discovery bridges the greatest part of the alleged gap between the susceptibility values measured from rock samples and the susceptibility values required to match the observed magnetic field signal.We expect the formulae and conclusions of this study to be a valuable tool for the quantitative interpretation of the Earth's global lithospheric magnetic field,through an inverse or forward modelling approach. 展开更多
关键词 lithospheric magnetic field forward calculation spherical harmonic analysis sensitivity analysis satellite magnetism
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A Review on Modeling Environmental Loading Effects and Their Contributions to Nonlinear Variations of Global Navigation Satellite System Coordinate Time Series 被引量:1
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作者 Zhao Li Weiping Jiang +3 位作者 Tonie van Dam Xiaowei Zou Qusen Chen Hua Chen 《Engineering》 2025年第4期26-37,共12页
Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including at... Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including atmospheric, hydrological, and nontidal ocean loading. Continuous improvements in the accuracy of surface mass loading products, performance of Earth models, and precise data-processing technologies have significantly advanced research on the effects of environmental loading on nonlinear variations in GNSS coordinate time series. However, owing to theoretical limitations, the lack of high spatiotemporal resolution surface mass observations, and the coupling of GNSS technology-related systematic errors, environmental loading and nonlinear GNSS reference station displacements remain inconsistent. The applicability and capability of these loading products across different regions also require further evaluation. This paper outlines methods for modeling environmental loading, surface mass loading products, and service organizations. In addition, it summarizes recent advances in applying environmental loading to address nonlinear variations in global and regional GNSS coordinate time series. Moreover, the scientific questions of existing studies are summarized, and insights into future research directions are provided. The complex nonlinear motion of reference stations is a major factor limiting the accuracy of the current terrestrial reference frame. Further refining the environmental load modeling method, establishing a surface mass distribution model with high spatiotemporal resolution and reliability, exploring other environmental load factors such as ice sheet and artificial mass-change effects, and developing an optimal data-processing model and strategy for reprocessing global reference station data consistently could contribute to the development of a millimeter-level nonlinear motion model for GNSS reference stations with actual physical significance and provide theoretical support for establishing a terrestrial reference frame with 1 mm accuracy by 2050. 展开更多
关键词 Environmental loading Global navigation satellite system Nonlinear variations Time series analysis Surface mass distribution Green’s function Spherical harmonic function
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A high-resolution lithospheric magnetic field model of China and surroundings by using CHAMP,Swarm,CSES-1,and MSS-1 satellite magnetic measurements and aeromagnetic anomaly data 被引量:1
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作者 Pan Zhang JinSong Du +5 位作者 Liang Yin Qing Yan JiaXuan Zhang HouPu Li Keke Zhang Chao Chen 《Earth and Planetary Physics》 2025年第3期686-696,共11页
The CUG_CLMFM3D series comprises high-resolution three-dimensional lithospheric magnetic field models for China and its surroundings.The first version,CUG_CLMFM3Dv1,is a spherical cap harmonic model integrating the WD... The CUG_CLMFM3D series comprises high-resolution three-dimensional lithospheric magnetic field models for China and its surroundings.The first version,CUG_CLMFM3Dv1,is a spherical cap harmonic model integrating the WDMAMv2(World Digital Magnetic Anomaly Map version 2)global magnetic anomaly grid and nearly a decade of CHAMP(Challenging Minisatellite Payload for Geophysical Research and Application)satellite vector data.It achieves a~5.7 km resolution but has limitations:the WDMAMv2 grid lacks high-resolution data in the southern Xinjiang and Tibet regions,which leads to missing small-to medium-scale anomalies,and unfiltered CHAMP data introduce low-frequency conflicts with global spherical harmonic models.Above the altitude of 150 km,correlations with global models drop below 0.9.The second version,CUG_CLMFM3Dv2,addresses these issues by incorporating 5-km-resolution aeromagnetic data and rigorously processed satellite data from CHAMP,Swarm,CSES-1(China Seismo-Electromagnetic Satellite 1),and MSS-1(Macao Science Satellite 1).The comparison analysis shows that the CUG_CLMFM3Dv2 captures finer high-frequency details and more stable long-wavelength signals,offering improved magnetic anomaly maps for further geological and geophysical studies. 展开更多
关键词 Macao Science Satellite 1 China Seismo-Electromagnetic Satellite 1 revised spherical cap harmonic analysis high resolution lithospheric magnetic field China and surroundings
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A Survey on the Existence of Harmonic Metrics on Vector Bundles
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作者 SHEN Zhenghan ZHANG Xi 《数学进展》 北大核心 2025年第2期390-404,共15页
In this paper,we give a survey on the existence of Hermitian-Einstein metrics and harmonic metrics.
关键词 Hermitian-Einstein metric harmonic metric holomorphic vector bundle non-Hermitian Yang-Mills bundle
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Optimizing the generation of second harmonic optical vortices from nonlinear photonic crystals
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作者 LIU Shiqiang ZHANG Xinyu +4 位作者 CHEN Yan LI Shifeng ZHAO Gang ZHU Shining HU Xiaopeng 《物理学进展》 北大核心 2025年第4期161-168,共8页
The generation of optical vortices from nonlinear photonic crystals(NPCs)with spatially modulated second-order nonlinearity offers a promising approach to extend the working wavelength and topological charge of vortex... The generation of optical vortices from nonlinear photonic crystals(NPCs)with spatially modulated second-order nonlinearity offers a promising approach to extend the working wavelength and topological charge of vortex beams for various applications.In this work,the second harmonic(SH)optical vortex beams generated from nonlinear fork gratings under Gaussian beam illumination are numerically investigated.The far-field intensity and phase distributions,as well as the orbital angular momentum(OAM)spectra of the SH beams,are analyzed for different structural topological charges and diffraction orders.Results reveal that higher-order diffraction and larger structural topological charges lead to angular interference patterns and non-uniform intensity distributions,deviating from the standard vortex profile.To optimize the SH vortex quality,the effects of the fundamental wave beam waist,crystal thickness,and grating duty cycle are explored.It is shown that increasing the beam waist can effectively suppress diffraction order interference and improve the beam’s quality.This study provides theoretical guidance for enhancing the performance of nonlinear optical devices based on NPCs. 展开更多
关键词 optical vortex nonlinear photonic crystal second harmonic generation orbital angular momentum
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A high output power 340 GHz balanced frequency doubler designed based on linear optimization method
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作者 LIU Zhi-Cheng ZHOU Jing-Tao +5 位作者 MENG Jin WEI Hao-Miao YANG Cheng-Yue SU Yong-Bo JIN Zhi JIA Rui 《红外与毫米波学报》 北大核心 2025年第2期184-191,共8页
In this paper,a linear optimization method(LOM)for the design of terahertz circuits is presented,aimed at enhancing the simulation efficacy and reducing the time of the circuit design workflow.This method enables the ... In this paper,a linear optimization method(LOM)for the design of terahertz circuits is presented,aimed at enhancing the simulation efficacy and reducing the time of the circuit design workflow.This method enables the rapid determination of optimal embedding impedance for diodes across a specific bandwidth to achieve maximum efficiency through harmonic balance simulations.By optimizing the linear matching circuit with the optimal embedding impedance,the method effectively segregates the simulation of the linear segments from the nonlinear segments in the frequency multiplier circuit,substantially improving the speed of simulations.The design of on-chip linear matching circuits adopts a modular circuit design strategy,incorporating fixed load resistors to simplify the matching challenge.Utilizing this approach,a 340 GHz frequency doubler was developed and measured.The results demonstrate that,across a bandwidth of 330 GHz to 342 GHz,the efficiency of the doubler remains above 10%,with an input power ranging from 98 mW to 141mW and an output power exceeding 13 mW.Notably,at an input power of 141 mW,a peak output power of 21.8 mW was achieved at 334 GHz,corresponding to an efficiency of 15.8%. 展开更多
关键词 linear optimization method(LOM) three-dimensional electromagnetic model(3D-EM) Harmonic impedance optimization Schottky planar diode Terahertz frequency doubler
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Nonlinear vibration and stability analysis of an aero-engine dual-rotor system subjected to high-frequency excitation
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作者 Rongzhou LIN Shuangxing REN +5 位作者 Lei HOU Zeyuan CHANG Zhonggang LI Yushu CHEN Nasser A.SAEED Mohamed S.MOHAMED 《Chinese Journal of Aeronautics》 2025年第7期227-247,共21页
This paper analyzes the nonlinear dynamic characteristics and stability of Aero-Engine Dual-Rotor(AEDR)systems under high-frequency excitation,based on the Adaptive Harmonic Balance with the Asymptotic Harmonic Select... This paper analyzes the nonlinear dynamic characteristics and stability of Aero-Engine Dual-Rotor(AEDR)systems under high-frequency excitation,based on the Adaptive Harmonic Balance with the Asymptotic Harmonic Selection(AHB-AHS)method.A finite element dynamic equation for the AEDR system is introduced,considering complex nonlinearities of the intershaft bearing,unbalanced excitations,and high-frequency excitation.A solving strategy combining the AHB-AHS method and improved arclength continuation method is proposed to solve highdimensional dynamic equations containing complex nonlinearities and to track periodic solutions with parameter variations.The Floquet theory is used to analyze the types of bifurcation points in the system and the stability of periodic motions.The results indicate that high-frequency excitation can couple high-order and low-order modes,especially when the system undergoes superharmonic resonance.High-frequency excitation leads to more combination frequency harmonics,among which N_(f)ω_(1)-2ω_(2)dominates.Furthermore,changing the parameters(amplitude and frequency)of high-frequency excitation widens or shifts the unstable regions of the system.These findings contribute to understanding the mechanism of high-frequency excitation on aero-engines and demonstrate that the proposed AHB-AHS method is a powerful tool for analyzing highdimensional complex nonlinear dynamic systems under multi-frequency excitation. 展开更多
关键词 AERO-ENGINE Nonlinear vibration High-dimensional rotor system INSTABILITY Harmonic balance method Adaptive harmonic balance method
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A novel harmonic resonance prevention measure for railway power conditioner-network-train interaction system
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作者 Shaofeng Xie Fan Zhong 《Railway Engineering Science》 2025年第2期290-310,共21页
The integration of a large number of power electronic converters,such as railway power conditioner(RPC),introduces a series of problems,including harmonic interaction,stability issues,and wideband resonance,into the r... The integration of a large number of power electronic converters,such as railway power conditioner(RPC),introduces a series of problems,including harmonic interaction,stability issues,and wideband resonance,into the railway power supply system.To address these challenges,this paper proposes a novel harmonic resonance prevention measure for RPC-network-train interaction system.Firstly,a harmonic model,a parallel resonance impedance model,a series resonance admittance model,and a control stability model are each established for the RPC-network-train interaction system.Secondly,a comprehensive resonance impact factor(CRIF)is proposed to efficiently and accurately identify the key components affecting resonance,and to provide the selection results of optimization parameters for resonance prevention.Next,the initially selected parameters are constrained by the requirements of ripple current,reactive power and stability.Subsequently,the impedance parameters(control parameters and filter parameters)of the RPC are optimized with the objective of reshaping the parallel resonance impedance and series resonance admittance of the RPC-network-train interaction system,ensuring the output current har-monics of RPC meet standards to achieve resonance prevention,while ensuring the stable operation of the RPC.Finally,the proposed resonance prevention measure is verified under both light load and heavy load conditions using a simulation platform and a hardware-in-the-loop experimental platform. 展开更多
关键词 Electrical railway Railway power conditioner(RPC) Harmonic interaction Series resonance Parallel resonance Harmonic resonance prevention
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An Improved FFT Algorithm for Spherical Harmonic Analysis and Synthesis
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作者 Su Yong Zhang Li-wei 《Applied Geophysics》 2025年第3期588-599,891,共13页
Spherical harmonic analysis(SHA)and synthesis(SHS)are widely used by researchers in various fields.Both numerical integration and least-squares methods can be employed for analysis and synthesis.However,these approach... Spherical harmonic analysis(SHA)and synthesis(SHS)are widely used by researchers in various fields.Both numerical integration and least-squares methods can be employed for analysis and synthesis.However,these approaches,when calculated via summation,are computationally intensive.Although the Fast Fourier Transform(FFT)algorithm is efficient,it is traditionally limited to processing global grid points starting from zero longitude.In this paper,we derive an improved FFT algorithm for spherical harmonic analysis and synthesis.The proposed algorithm eliminates the need for grid points to start at zero longitude,thereby expanding the applicability of FFT-based methods.Numerical experiments demonstrate that the new algorithm retains the computational efficiency of conventional FFT while achieving accuracy comparable to the summation method.Consequently,it enables direct harmonic coefficient calculation from global grid data without requiring interpolation to align with zero longitude.Additionally,the algrithm can generate grid points with equi-angular spacing using the improved FFT algorithm,starting from non-zero longitudes.To address the loss of orthogonality in latitude due to discrete spherical grids,a quadrature weight factor-dependent on grid type(e.g.,regular or Gauss grid)-is incorporated,as summarized in this study. 展开更多
关键词 Spherical harmonic analysis Spherical harmonic synthesis FFT Quadrature weight
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Simultaneous second and third harmonics generation in periodically poled lithium niobate:Coupling and competition
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作者 Junming Liu Liqiang Liu +1 位作者 Lihong Hong Zhiyuan Li 《Chinese Physics B》 2025年第8期591-599,共9页
Conventional approaches for obtaining the second and third harmonics typically employ several nonlinear crystals to generate them,which is restricted in application due to the complexity of the optical path and the bu... Conventional approaches for obtaining the second and third harmonics typically employ several nonlinear crystals to generate them,which is restricted in application due to the complexity of the optical path and the bulkiness of the device.In this work,we present a comprehensive theoretical and numerical investigation of the simultaneous generation and competition between the second harmonic waves(SHW)and the third harmonic waves(THW)in a single nonlinear crystal.Through analyzing both small-signal and large-signal regimes,we reveal the complex coupling mechanisms between SHW and THW generation processes.Using periodically poled lithium niobate as an example,we demonstrate that the relative conversion efficiencies between SHW and THW can be freely adjusted by controlling the input fundamental wave power.This work provides new insights for designing efficient frequency converters capable of generating both SHW and THW outputs with controllable intensity ratios. 展开更多
关键词 second harmonic generation third harmonic generation quasi-phase matching periodically poled lithium niobate
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Fast flutter and forced response analyses using a cubic-B-spline-based time collocation method
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作者 Hangkong WU Hongbin PU +1 位作者 Xiuquan HUANG Dingxi WANG 《Chinese Journal of Aeronautics》 2025年第3期96-108,共13页
Flutter and forced response, as two main branches of aeroelasticity, can lead to high-cycle fatigue failure of turbomachinery blades. Efficiently and accurately assessing aeroelastic performance of turbomachinery blad... Flutter and forced response, as two main branches of aeroelasticity, can lead to high-cycle fatigue failure of turbomachinery blades. Efficiently and accurately assessing aeroelastic performance of turbomachinery blades is essential in the routine design. In this work, the Time Collocation Method (TCM) which uses the cubic B-spline to approximate flow variables is first thoroughly studied and then combined with the moving grid technique to analyze aeroelastic flow fields. To showcase its advantage over the Harmonic Balance (HB) method which uses a truncated Fourier series to approximately represent flow variables, a matrix analysis of the one-dimensional advection equation is first performed. The results of stability analysis are verified by two test cases: the Durham linear oscillating turbine cascade and a two-blade-row transonic compressor. The vibration of the blade of the first case is driven by a motor while the excitation force of the second case comes from blade row interaction. The results show that the time collocation method has a faster convergence rate and is more stable than the harmonic balance method, especially for cases with a large maximum grid reduced frequency. More importantly, the time collocation method is capable of accurately predicting aeroelastic performance of turbomachinery blades. 展开更多
关键词 Time collocation Harmonic balance FLUTTER Forced response Turbomachineryi Aeroelasticity
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Harmonization of Heart Disease Dataset for Accurate Diagnosis:A Machine Learning Approach Enhanced by Feature Engineering
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作者 Ruhul Amin Md.Jamil Khan +2 位作者 Tonway Deb Nath Md.Shamim Reza Jungpil Shin 《Computers, Materials & Continua》 2025年第3期3907-3919,共13页
Heart disease includes a multiplicity of medical conditions that affect the structure,blood vessels,and general operation of the heart.Numerous researchers have made progress in correcting and predicting early heart d... Heart disease includes a multiplicity of medical conditions that affect the structure,blood vessels,and general operation of the heart.Numerous researchers have made progress in correcting and predicting early heart disease,but more remains to be accomplished.The diagnostic accuracy of many current studies is inadequate due to the attempt to predict patients with heart disease using traditional approaches.By using data fusion from several regions of the country,we intend to increase the accuracy of heart disease prediction.A statistical approach that promotes insights triggered by feature interactions to reveal the intricate pattern in the data,which cannot be adequately captured by a single feature.We processed the data using techniques including feature scaling,outlier detection and replacement,null and missing value imputation,and more to improve the data quality.Furthermore,the proposed feature engineering method uses the correlation test for numerical features and the chi-square test for categorical features to interact with the feature.To reduce the dimensionality,we subsequently used PCA with 95%variation.To identify patients with heart disease,hyperparameter-based machine learning algorithms like RF,XGBoost,Gradient Boosting,LightGBM,CatBoost,SVM,and MLP are utilized,along with ensemble models.The model’s overall prediction performance ranges from 88%to 92%.In order to attain cutting-edge results,we then used a 1D CNN model,which significantly enhanced the prediction with an accuracy score of 96.36%,precision of 96.45%,recall of 96.36%,specificity score of 99.51%and F1 score of 96.34%.The RF model produces the best results among all the classifiers in the evaluation matrix without feature interaction,with accuracy of 90.21%,precision of 90.40%,recall of 90.86%,specificity of 90.91%,and F1 score of 90.63%.Our proposed 1D CNN model is 7%superior to the one without feature engineering when compared to the suggested approach.This illustrates how interaction-focused feature analysis can produce precise and useful insights for heart disease diagnosis. 展开更多
关键词 Heart disease HARMONIZATION feature interaction PCA model hyper tuning machine learning
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Improvement of Torque and Loss Characteristics for an In-wheel Permanent Magnet Motor based on Dominant Airgap Harmonic
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作者 Jiawei Ren Xiaoyong Zhu +1 位作者 Li Quan Zixuan Xiang 《CES Transactions on Electrical Machines and Systems》 2025年第3期313-319,共7页
In this paper,a 12/14-pole permanent magnet in-wheel motor is studied for potential in-wheel application,and the torque and loss are improved simultaneously based on designing and optimizing the corresponding dominant... In this paper,a 12/14-pole permanent magnet in-wheel motor is studied for potential in-wheel application,and the torque and loss are improved simultaneously based on designing and optimizing the corresponding dominant harmonics.The key of this study is to evaluate the contributions of harmonics on torque and loss,and further determines the harmonics related to them.Based on this,the torque enhancement factor and loss suppression factor are defined based on the selected dominant harmonics.And,the two factors are set as the optimization objectives,aiming at improving the characteristics of torque and loss.At the same time,to achieve an efficient optimization,a layered optimization method is presented,which includes magnet source layer and permeance layer.Based on the optimization,the motor torque is improved effectively,while the rotor iron loss is also reduced significantly.Then,a prototype motor is manufactured for experimental test.Finally,the simulation analysis and test results verify the validation of the studied motor and the proposed optimization method based on dominant harmonics. 展开更多
关键词 In-wheel motor Flux modulation Harmonic analysis TORQUE Rotor loss
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Generation of Isolated Attosecond Pulses by the Harmonic Spectrum of MgO under a Three-Color Laser Pulse
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作者 Jiaqi Chen Wenli Jiang +2 位作者 Yue Qiao Yujun Yang Jigen Chen 《Chinese Physics Letters》 2025年第1期48-52,共5页
This study examines the high-order harmonic radiation behavior of MgO crystals driven by combined pulses based on the numerical solution of the semiconductor Bloch equation.We found that compared with the monochromati... This study examines the high-order harmonic radiation behavior of MgO crystals driven by combined pulses based on the numerical solution of the semiconductor Bloch equation.We found that compared with the monochromatic pulse,the MgO crystal can radiate a continuous harmonic spectrum with two platforms driven by the three-color combined pulse.The reason is that under the three-color combined pulse,the electron ionization and recombination can be effectively controlled within a half-optical cycle of the laser pulse.Using this continuous spectrum,we synthesized an isolated attosecond pulse with a duration of approximately 370 as.This study provides a new perspective on all-solid-state compact optical devices. 展开更多
关键词 PULSE optical HARMONIC
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