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Enhancing the resolution of seismic data based on the generalized S-transform 被引量:3
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作者 Tian Jianhua Song Wei Yang Feizhou 《Petroleum Science》 SCIE CAS CSCD 2009年第2期153-157,共5页
In this paper, we analyze the seismic signal in the time-frequency domain using the generalized S-transform combined with spectrum modeling. Without assuming that the reflection coefficients are random white noise as ... In this paper, we analyze the seismic signal in the time-frequency domain using the generalized S-transform combined with spectrum modeling. Without assuming that the reflection coefficients are random white noise as in the conventional resolution-enhanced techniques, the wavelet which changes with time and frequency was simulated and eliminated. After using the inverse S-transform for the processed instantaneous spectrum, the signal in the time domain was obtained again with a more balanced spectrum and broader frequency band. The quality of seismic data was improved without additional noise. 展开更多
关键词 Time-frequency domain generalized s-transform spectrum modeling instantaneous spectrum balanced spectrum
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A Protection Method of VSC-HVDC Cables Based on Generalized S-Transform 被引量:3
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作者 Weishi Man Xiaoman Bei Zhiyu Zhang 《Energy and Power Engineering》 2021年第4期1-10,共10页
<div style="text-align:justify;"> Generalized S-transform is a time-frequency analysis method which has higher resolution than S-transform. It can precisely extract the time-amplitude characteristics o... <div style="text-align:justify;"> Generalized S-transform is a time-frequency analysis method which has higher resolution than S-transform. It can precisely extract the time-amplitude characteristics of different frequency components in the signal. In this paper, a novel protection method for VSC-HVDC (Voltage source converter based high voltage DC) based on Generalized S-transform is proposed. Firstly, extracting frequency component of fault current by Generalized S-transform and using mutation point of high frequency to determine the fault time. Secondly, using the zero-frequency component of fault current to eliminate disturbances. Finally, the polarity of sudden change currents in the two terminals is employed to discriminate the internal and external faults. Simulations in PSCAD/EMTDC and MATLAB show that the proposed method can distinguish faults accurately and effectively. </div> 展开更多
关键词 generalized s-transform VSC-HVDC Phase-Mode Transformation DC Cable Protection
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Detection and correction of level echo based on generalized S-transform and singular value decomposition 被引量:1
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作者 ZHU Tianliang WANG Xiaopeng WANG Qi 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2021年第4期442-448,共7页
The echo of the material level is non-stationary and contains many singularities.The echo contains false echoes and noise,which affects the detection of the material level signals,resulting in low accuracy of material... The echo of the material level is non-stationary and contains many singularities.The echo contains false echoes and noise,which affects the detection of the material level signals,resulting in low accuracy of material level measurement.A new method for detecting and correcting the material level signal is proposed,which is based on the generalized S-transform and singular value decomposition(GST-SVD).In this project,the change of material level is regarded as the low speed moving target.First,the generalized S-transform is performed on the echo signals.During the transformation process,the variation trend of window of the generalized S-transform is adjusted according to the frequency distribution characteristics of the material level echo signal,achieving the purpose of detecting the signal.Secondly,the SVD is used to reconstruct the time-frequency coefficient matrix.At last,the reconstructed time-frequency matrix performs an inverse transform.The experimental results show that the method can accurately detect the material level echo signal,and it can reserve the detailed characteristics of the signal while suppressing the noise,and reduce the false echo interference.Compared with other methods,the material level measurement error does not exceed 4.01%,and the material level measurement accuracy can reach 0.40%F.S. 展开更多
关键词 echo signal false echo generalized s-transform singular value decomposition(SVD) level measurement
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Functional generalized estimating equation model to detect glaucomatous visual field progression
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作者 Sanghun Jeong Hwayeong Kim +4 位作者 Sangwoo Moon EunAh Kim Hojin Yang Jiwoong Lee Kouros Nouri-Mahdavi 《International Journal of Ophthalmology(English edition)》 2026年第2期302-311,共10页
AIM:To build a functional generalized estimating equation(GEE)model to detect glaucomatous visual field progression and compare the performance of the proposed method with that of commonly employed algorithms.METHODS:... AIM:To build a functional generalized estimating equation(GEE)model to detect glaucomatous visual field progression and compare the performance of the proposed method with that of commonly employed algorithms.METHODS:Totally 716 eyes of 716 patients with primary open angle glaucoma(POAG)with at least 5 reliable 24-2 test results and 2y of follow-up were selected.The functional GEE model was used to detect perimetric progression in the training dataset(501 eyes).In the testing dataset(215 eyes),progression was evaluated the functional GEE model,mean deviation(MD)and visual field index(VFI)rates of change,Advanced Glaucoma Intervention Study(AGIS)and Collaborative Initial Glaucoma Treatment Study(CIGTS)scores,and pointwise linear regression(PLR).RESULTS:The proposed method showed the highest proportion of eyes detected as progression(54.4%),followed by the VFI rate(34.4%),PLR(23.3%),and MD rate(21.4%).The CIGTS and AGIS scores had a lower proportion of eyes detected as progression(7.9%and 5.1%,respectively).The time to detection of progression was significantly shorter for the proposed method than that of other algorithms(adjusted P≤0.019).The VFI rate displayed moderate pairwise agreement with the proposed method(k=0.47).CONCLUSION:The functional GEE model shows the highest proportion of eyes detected as perimetric progression and the shortest time to detect perimetric progression in patients with POAG. 展开更多
关键词 functional generalized estimating equation model primary open angle glaucoma perimetric progression
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Ramsey numbers of edge-critical graphs versus large generalized fans
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作者 Taiping Jiang Xinmin Hou 《中国科学技术大学学报》 北大核心 2025年第5期62-66,61,I0002,共7页
Given two graphs G and H,the Ramsey number R(G,H)is the smallest positive integer N such that every 2-coloring of the edges of K_(N)contains either a red G or a blue H.Let K_(N-1)■K_(1,k)be the graph obtained from K_... Given two graphs G and H,the Ramsey number R(G,H)is the smallest positive integer N such that every 2-coloring of the edges of K_(N)contains either a red G or a blue H.Let K_(N-1)■K_(1,k)be the graph obtained from K_(N-1)by adding anew vertexνconnecting k vertices of K_(N-1).A graph G withχ(G)=k+1 is called edge-critical if G contains an edge e such thatχ(G-e)=k.A considerable amount of research has been conducted by previous scholars on Ramsey numbers ofgraphs.In this study,we show that for an edge-critical graph G with x(G)=k+1,when k≥2,1≥2,and n is sufficiently large,R(G,K_(1)+nK_(t))=knt+1 and r,(G,K_(1)+nK_(t))=(k-1)nt+1. 展开更多
关键词 Ramsey number color critical graph generalized fan
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Generalized Quasidiagonal Extensions of C^(*)-algebras
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作者 GAN Yuntao YAO Hongliang CHEN Peixin 《数学进展》 北大核心 2025年第6期1327-1332,共6页
This paper introduced the concept of generalized quasidiagonal extension of C^(*)-algebras and gave some basic properties.We show that the extension algebra preserves quasidiagonality and finitary in generalized quasi... This paper introduced the concept of generalized quasidiagonal extension of C^(*)-algebras and gave some basic properties.We show that the extension algebra preserves quasidiagonality and finitary in generalized quasidiagonal extension.We give also an example of generalized quasidiagonal extension,which is not quasidiagonal extension. 展开更多
关键词 C^(*)-algebra quasidiagonality generalized quasidiagonal extension
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Dominating Induced Matching of Generalized Petersen Graphs
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作者 CHEN Ming ZANG Weiqi ZHOU Shan 《数学进展》 北大核心 2025年第6期1223-1232,共10页
A dominating induced matching(DIM)of G is an induced matching that dominates every edge of G.In this note,we completely determine the number of DIMs in the generalized Petersen graph P(n,k).We prove that if P(n,k)is a... A dominating induced matching(DIM)of G is an induced matching that dominates every edge of G.In this note,we completely determine the number of DIMs in the generalized Petersen graph P(n,k).We prove that if P(n,k)is a generalized Petersen graph with n=0(mod 5)and k=2,3(mod 5),then E(P(n,k))can be partitioned into five DIMs.Meanwhile,in the left cases k=0,1,4(mod 5),we build some counterexamples to show that there exist some P(n,k)'s which are DIM-free. 展开更多
关键词 dominating induced matching generalized Petersen graph
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Temperature control for liquid-cooled fuel cells based on fuzzy logic and variable-gain generalized supertwisting algorithm
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作者 CHEN Lin JIA Zhi-huan +1 位作者 DING Tian-wei GAO Jin-wu 《控制理论与应用》 北大核心 2025年第8期1596-1605,共10页
The liquid cooling system(LCS)of fuel cells is challenged by significant time delays,model uncertainties,pump and fan coupling,and frequent disturbances,leading to overshoot and control oscillations that degrade tempe... The liquid cooling system(LCS)of fuel cells is challenged by significant time delays,model uncertainties,pump and fan coupling,and frequent disturbances,leading to overshoot and control oscillations that degrade temperature regulation performance.To address these challenges,we propose a composite control scheme combining fuzzy logic and a variable-gain generalized supertwisting algorithm(VG-GSTA).Firstly,a one-dimensional(1D)fuzzy logic controler(FLC)for the pump ensures stable coolant flow,while a two-dimensional(2D)FLC for the fan regulates the stack temperature near the reference value.The VG-GSTA is then introduced to eliminate steady-state errors,offering resistance to disturbances and minimizing control oscillations.The equilibrium optimizer is used to fine-tune VG-GSTA parameters.Co-simulation verifies the effectiveness of our method,demonstrating its advantages in terms of disturbance immunity,overshoot suppression,tracking accuracy and response speed. 展开更多
关键词 liquid-cooled fuel cell temperature control generalized supertwisting algorithm fuzzy control equilibrium optimizer
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Compact Commutators of Bilinear Fractional Integral Operators on Generalized Morrey Spaces
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作者 KU Fuli 《Wuhan University Journal of Natural Sciences》 2025年第5期463-470,共8页
This paper considers compactness of the commutator[b,I_(α)]i(i=1,2),where I_(α)is a bilinear fractional integral operator,and b is a function in generalized Campanato spaces with variable growth condition.The author... This paper considers compactness of the commutator[b,I_(α)]i(i=1,2),where I_(α)is a bilinear fractional integral operator,and b is a function in generalized Campanato spaces with variable growth condition.The author gives sufficient conditions for the compactness of[b,I_(α)],(i=1,2)from the product of generalized Morrey spaces to generalized Morrey spaces. 展开更多
关键词 fractional integral COMMUTATORS COMPACTNESS generalized Campanato spaces generalized Morrey spaces
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Multiparameter generalized universal characters and multiparameter generalized B-type universal characters
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作者 Jingfan Wang Zhaowen Yan 《Chinese Physics B》 2025年第1期215-226,共12页
We construct the quantum fields presentation of the generalized universal character and the generalized B-type universal character,and by acting the quantum fields presentations to the constant 1,the generating functi... We construct the quantum fields presentation of the generalized universal character and the generalized B-type universal character,and by acting the quantum fields presentations to the constant 1,the generating functions are derived.Furthermore,we introduce two integrable systems known as the generalized UC(GUC)hierarchy and the generalized Btype UC(GBUC)hierarchy satisfied by the generalized universal character and the generalized B-type universal character,respectively.Based on infinite sequences of complex numbers,we further establish the multiparameter generalized universal character and the multiparameter generalized B-type universal character,which have been proved to be solutions of the GUC hierarchy and the GBUC hierarchy,respectively. 展开更多
关键词 symmetric functions quantum fields generating functions multiparameter generalized universal characters
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New insights on generalized heat conduction and thermoelastic coupling models
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作者 Yue HUANG Lei YAN +1 位作者 Hua WU Yajun YU 《Applied Mathematics and Mechanics(English Edition)》 2025年第8期1533-1550,共18页
With the miniaturization of devices and the development of modern heating technologies,the generalization of heat conduction and thermoelastic coupling has become crucial,effectively emulating the thermodynamic behavi... With the miniaturization of devices and the development of modern heating technologies,the generalization of heat conduction and thermoelastic coupling has become crucial,effectively emulating the thermodynamic behavior of materials in ultrashort time scales.Theoretically,generalized heat conductive models are considered in this work.By analogy with mechanical viscoelastic models,this paper further enriches the heat conduction models and gives their one-dimensional physical expression.Numerically,the transient thermoelastic response of the slim strip material under thermal shock is investigated by applying the proposed models.First,the analytical solution in the Laplace domain is obtained by the Laplace transform.Then,the numerical results of the transient responses are obtained by the numerical inverse Laplace transform.Finally,the transient responses of different models are analyzed and compared,and the effects of material parameters are discussed.This work not only opens up new research perspectives on generalized heat conductive and thermoelastic coupling theories,but also is expected to be beneficial for the deeper understanding of the heat wave theory. 展开更多
关键词 generalized heat conduction thermoelastic coupling transient response generalized Cattaneo-Vernotte(CV)model generalized Green-Naghdi(GN)model
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GÂTEAUX DIRECTIONAL DIFFERENTIABILITY OF THE GENERALIZED METRIC PROJECTION IN BANACH SPACES
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作者 Jinlu LI 《Acta Mathematica Scientia》 2025年第4期1597-1618,共22页
Let X be a real uniformly convex and uniformly smooth Banach space and C a nonempty closed and convex subset of X.Let Π_(C):X→C denote the generalized metric projection operator introduced by Alber in[1].In this pap... Let X be a real uniformly convex and uniformly smooth Banach space and C a nonempty closed and convex subset of X.Let Π_(C):X→C denote the generalized metric projection operator introduced by Alber in[1].In this paper,we define the Gâteaux directional differentiability of Π_(C).We investigate some properties of the Gâteaux directional differentiability of Π_(C).In particular,if C is a closed ball,or a closed and convex cone(including proper closed subspaces),or a closed and convex cylinder,then,we give the exact representations of the directional derivatives of Π_(C).By comparing the results in[12]and this paper,we see the significant difference between the directional derivatives of the generalized metric projection operator Π_(C) and the Gâteaux directional derivatives of the standard metric projection operator PC. 展开更多
关键词 uniformly convex and uniformly smooth Banach space the generalized metric projection directional differentiability of the generalized metric projection directional derivative of the generalized metric projection
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Application of Generalized Argumentation in the Context of Chinese Doctor-patient Communication—An Argument Recognition Mixed with Statistical Approach
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作者 Niu Ju Yanjin Chen 《逻辑学研究》 2025年第6期88-103,共16页
This study aims to reveal the prototypical argumentative patterns employed in situations where patient distrust arises in China.Based on the quantitative analysis of data from a general social survey,we focus on a dis... This study aims to reveal the prototypical argumentative patterns employed in situations where patient distrust arises in China.Based on the quantitative analysis of data from a general social survey,we focus on a distinctive phenomenon that while a majority of Chinese respondents trust the medical profession as a whole,significant distrust exists toward doctors'skills and ethics,particularly among older,urban,and higher income populations.Qualtatively,we employ Generalized Argumentation Theory to analyze Chinese clinical dialogues,identifying three kinds of prototypical argumentative patterns in situations of patient distrust.Methodologically,this article shows the value of combining statistical analysis with goal-oriented Generalized Argumentation research to reconcile the tricky trust phenomenon of Chinese doctor-patient communication. 展开更多
关键词 generalized argumentation general social surveywe argument recognition generalized argumentation theory quantitative analysis statistical approach patient distrust Chinese doctor patient communication
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Herglotz type Noether theorems of nonholonomic systems with generalized fractional derivatives
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作者 Yuan-Yuan Deng Yi Zhang 《Theoretical & Applied Mechanics Letters》 2025年第2期179-187,共9页
Fractional calculus is widely used to deal with nonconservative dynamics because of its memorability and non-local properties.In this paper,the Herglotz principle with generalized operators is discussed,and the Herglo... Fractional calculus is widely used to deal with nonconservative dynamics because of its memorability and non-local properties.In this paper,the Herglotz principle with generalized operators is discussed,and the Herglotz type equations for nonholonomic systems are established.Then,the Noether symmetries are studied,and the conserved quantities are obtained.The results are extended to nonholonomic canonical systems,and the Herglotz type canonical equations and the Noether theorems are obtained.Two examples are provided to demonstrate the validity of the methods and results. 展开更多
关键词 Nonholonomic system Herglotz principle Noether theorem generalized operators
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Generalized uncertainty principle from the regularized self-energy
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作者 Kimet Jusufi Ahmed Farag Ali 《Communications in Theoretical Physics》 2025年第1期92-100,共9页
We use the Schrödinger–Newton equation to calculate the regularized self-energy of a particle using a regular self-gravitational and electrostatic potential derived in string T-duality.The particle mass M is no ... We use the Schrödinger–Newton equation to calculate the regularized self-energy of a particle using a regular self-gravitational and electrostatic potential derived in string T-duality.The particle mass M is no longer concentrated into a point but is diluted and described by a quantum-corrected smeared energy density resulting in corrections to the energy of the particle,which is interpreted as a regularized self-energy.We extend our results and find corrections to the relativistic particles using the Klein–Gordon,Proca and Dirac equations.An important finding is that we extract a form of the generalized uncertainty principle(GUP)from the corrected energy.This form of the GUP is shown to depend on the nature of particles;namely,for bosons(spin 0 and spin 1)we obtain a quadratic form of the GUP,while for fermions(spin 1/2)we obtain a linear form.The correlation we find between spin and GUP may offer insights for investigating quantum gravity. 展开更多
关键词 generalized uncertainty principle T-DUALITY regularized self-energy
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A Nonlinear Analysis Approach to Asymptotic Behavior of Solutions of the Generalized Emden-Fowler Equation
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作者 Liangping QI Guowei ZONG 《Journal of Mathematical Research with Applications》 2025年第4期521-536,共16页
We introduce a new method to study the asymptotic behavior of solutions on the basis of the continuation theory for k-set contractions.We apply this technique to show the existence of nontrivial decaying solutions to ... We introduce a new method to study the asymptotic behavior of solutions on the basis of the continuation theory for k-set contractions.We apply this technique to show the existence of nontrivial decaying solutions to the sup-linear generalized Emden-Fowler equation and the existence of asymptotically linear solutions to the sub-linear one. 展开更多
关键词 generalized Emden-Fowler equation asymptotic behavior k-set contractions
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ON GENERALIZED KISSING NUMBERS OF CONVEX BODIES
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作者 Yiming LI Chuanming ZONG 《Acta Mathematica Scientia》 2025年第1期72-95,共24页
In 1694,Gregory and Newton proposed the problem to determine the kissing number of a rigid material ball.This problem and its higher dimensional generalization have been studied by many mathematicians,including Minkow... In 1694,Gregory and Newton proposed the problem to determine the kissing number of a rigid material ball.This problem and its higher dimensional generalization have been studied by many mathematicians,including Minkowski,van der Waerden,Hadwiger,Swinnerton-Dyer,Watson,Levenshtein,Odlyzko,Sloane and Musin.In this paper,we introduce and study a further generalization of the kissing numbers for convex bodies and obtain some exact results,in particular for balls in dimensions three,four and eight. 展开更多
关键词 convex body generalized kissing number Eg lattice
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MULTIPLE POSITIVE SOLUTIONS FOR THE GENERALIZED QUASILINEAR SCHRÖDINGER EQUATION IN R^(N)
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作者 Yongpeng CHEN Zhipeng YANG 《Acta Mathematica Scientia》 2025年第5期2010-2028,共19页
In this paper,we investigate the generalized quasilinear Schrödinger equation:-div(g2(u)▽u)+g(u)g'(u)|▽u|2+u=P(εx)|u|αp-2u,x∈R^(N),where N>3,g:R→R+is a C1 even function,g(0)=1,g'(s)≥0 for all s... In this paper,we investigate the generalized quasilinear Schrödinger equation:-div(g2(u)▽u)+g(u)g'(u)|▽u|2+u=P(εx)|u|αp-2u,x∈R^(N),where N>3,g:R→R+is a C1 even function,g(0)=1,g'(s)≥0 for all s≥0,g(s)=β|s|α-1+O(|s|γ-1)as s→∞for some constantsα∈[1,2],β>0,γ<αand(α-1)g(s)≥g'(s)s for all s≥0,ε>0 is a positive parameter,and p∈(2,2^(*)).We will study the impact of the nonlinearity’s coefficient P(x)on the quantity of positive solutions. 展开更多
关键词 variational methods generalized quasilinear equation
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Efficacy of electroacupuncture for cervical spondylosis-related pain in patients with generalized anxiety disorder
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作者 Zhe Li Yu Gao +1 位作者 Dong Yan Yi-Hui Feng 《World Journal of Psychiatry》 2025年第11期168-178,共11页
BACKGROUND Cervical spondylosis(CS)frequently co-occurs with generalized anxiety disorder(GAD),presenting a complex clinical challenge.Managing CS-related pain in patients with GAD is particularly challenging because ... BACKGROUND Cervical spondylosis(CS)frequently co-occurs with generalized anxiety disorder(GAD),presenting a complex clinical challenge.Managing CS-related pain in patients with GAD is particularly challenging because of the bidirectional relationship between pain and anxiety,necessitating integrated treatment strategies.AIM To evaluate the efficacy of electroacupuncture(EA)in treating CS-related pain and anxiety in patients with GAD.METHODS This retrospective cohort study analyzed data from 83 patients with CS-related pain and GAD who received EA treatment over 2-year period.Pain intensity was assessed using the visual analog scale,and anxiety symptoms were measured using the Hamilton Anxiety Rating Scale.Additionally,neuroinflammatory markers,including interleukin-6,tumor necrosis factor-alpha,and high-sensitivity C-reactive protein,were examined.Outcomes were evaluated at baseline,after 4 weeks,and after 8 weeks of treatment.RESULTS EA treatment significantly reduced CS-related pain(mean visual analog scale reduction:3.24±1.18;P<0.001)and improved anxiety symptoms(mean Hamilton Anxiety Rating Scale reduction:7.83±2.65;P<0.001)after 8 weeks of treatment.Neuroinflammatory markers also showed significant reductions,with interleukin-6 and tumor necrosis factor-alpha levels decreasing by 32.7%and 28.5%,respectively(P<0.01).Pain reduction was significantly correlated with improvements in anxiety symptoms(r=0.68;P<0.001)and a decrease in inflammatory markers(r=0.54;P<0.01).CONCLUSION EA demonstrates significant efficacy in reducing CS-related pain in patients with comorbid GAD,along with concurrent improvements in anxiety symptoms and neuroinflammatory profiles.These findings suggest that EA may offer a valuable integrative approach for managing this complex clinical presentation,potentially addressing both pain and anxiety through the modulation of neuroinflammatory pathways. 展开更多
关键词 ELECTROACUPUNCTURE Cervical spondylosis generalized anxiety disorder NEUROINFLAMMATION Pain management
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A Novel Property of Generalized Fibonacci Sequence in Grids
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作者 YANG Zi-xian BAI Jian-chao 《Chinese Quarterly Journal of Mathematics》 2025年第1期103-110,共8页
Fibonacci sequence,generated by summing the preceding two terms,is a classical sequence renowned for its elegant properties.In this paper,leveraging properties of generalized Fibonacci sequences and formulas for conse... Fibonacci sequence,generated by summing the preceding two terms,is a classical sequence renowned for its elegant properties.In this paper,leveraging properties of generalized Fibonacci sequences and formulas for consecutive sums of equidistant sub-sequences,we investigate the ratio of the sum of numbers along main-diagonal and sub-diagonal of odd-order grids containing generalized Fibonacci sequences.We show that this ratio is solely dependent on the order of the grid,providing a concise and splendid identity. 展开更多
关键词 generalized Fibonacci sequence Fibonacci identity Odd-order grid Geometric property
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