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On the Weyl’s Lemma for Triharmonic Functions
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作者 ZHENG Run-jie ZENG Jia-min FANG Yi 《Chinese Quarterly Journal of Mathematics》 2024年第3期288-294,共7页
In this paper,by choosing some appropriate test functions,we prove the Weyl’s lemma for triharmonic functions based on the new type of mean value formulas.
关键词 Weyl’s lemma harmonic functions Triharmonic functions Test functions Mean value formulas
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A Subclass of Harmonic Functions Associated with Wright’s Hypergeometric Functions 被引量:1
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作者 Gangadharan Murugusundaramoorthy Kalliyapan Vijaya 《Applied Mathematics》 2010年第2期87-93,共7页
We introduce a new class of complex valued harmonic functions associated with Wright hypergeometric functions which are orientation preserving and univalent in the open unit disc. Further we define, Wright generalized... We introduce a new class of complex valued harmonic functions associated with Wright hypergeometric functions which are orientation preserving and univalent in the open unit disc. Further we define, Wright generalized operator on harmonic function and investigate the coefficient bounds, distortion inequalities and extreme points for this generalized class of functions. 展开更多
关键词 harmonic UNIVALENT STARLIKE functionS harmonic Convex functionS Wright HYPERGEOMETRIC functionS Raina-Dziok Operator Distortion Bounds Extreme Points
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THE SCHUR HARMONIC CONVEXITY FOR A CLASS OF SYMMETRIC FUNCTIONS 被引量:13
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作者 褚玉明 孙天川 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1501-1506,共6页
In this article, we prove that the symmetric function Fn(x,r)=∑i1+i2+……in=r(x1(i1x2^i2……xn^in)1/r is Schur harmonic convex for x ∈ R+n and r ∈N -=(1, 2, 3,...} As its applications, some analytic inequa... In this article, we prove that the symmetric function Fn(x,r)=∑i1+i2+……in=r(x1(i1x2^i2……xn^in)1/r is Schur harmonic convex for x ∈ R+n and r ∈N -=(1, 2, 3,...} As its applications, some analytic inequalities are established. 展开更多
关键词 symmetric function Schur convex Schur harmonic convex
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A New Class of Harmonic Univalent Functions by the Generalized Salagean Operator 被引量:6
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作者 LI Shuhai LIU Peide 《Wuhan University Journal of Natural Sciences》 CAS 2007年第6期965-970,共6页
A complex-valued harmonic functions that are univalent and sense preserving in the unit disk U can be written in the form f = h + g^-, where h and g are analytic in U. We define and investigate a new class SHPλ(α... A complex-valued harmonic functions that are univalent and sense preserving in the unit disk U can be written in the form f = h + g^-, where h and g are analytic in U. We define and investigate a new class SHPλ(α,β)by generalized Salagean operator of harmonic univalent functions. We give sufficient coefficient conditions for normalized harmonic functions in the class SHPλ(α,β) These conditions are also shown to be necessary when the coefficients are negative. This leads to distortion bounds and extreme points. 展开更多
关键词 harmonic function Salagean operator extreme point distortion bounds
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HARMONIC FUNCTION WITH CORRELATED COEFFICIENTS 被引量:2
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作者 Jacek DZIOK 《Acta Mathematica Scientia》 SCIE CSCD 2019年第6期1661-1673,共13页
In the paper we introduce an idea of harmonic functions with correlated coefficients which generalize the ideas of harmonic functions with negative coefficients introduced by Silverman and harmonic functions with vary... In the paper we introduce an idea of harmonic functions with correlated coefficients which generalize the ideas of harmonic functions with negative coefficients introduced by Silverman and harmonic functions with varying coefficients defined by Jahangiri and Silverman. Next we define classes of harmonic functions with correlated coefficients in terms of generalized Dziok-Srivastava operator. By using extreme points theory, we obtain estimations of classical convex functionals on the defined classes of functions. Some applications of the main results are also considered. 展开更多
关键词 harmonic functionS subORDINATION STARLIKE functionS Dziok-Srivastava operator CORRELATED COEFFICIENTS
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ON THE LOWER BOUND FOR A CLASS OF HARMONIC FUNCTIONS IN THE HALF SPACE 被引量:4
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作者 张艳慧 邓冠铁 高洁欣 《Acta Mathematica Scientia》 SCIE CSCD 2012年第4期1487-1494,共8页
The main objective is to derive a lower bound from an upper one for harmonic functions in the half space, which extends a result of B. Y. Levin from dimension 2 to dimension n 〉 2. To this end, we first generalize th... The main objective is to derive a lower bound from an upper one for harmonic functions in the half space, which extends a result of B. Y. Levin from dimension 2 to dimension n 〉 2. To this end, we first generalize the Carleman's formula for harmonic functions in the half plane to higher dimensional half space, and then establish a Nevanlinna's representation for harmonic functions in the half sphere by using HSrmander's theorem. 展开更多
关键词 harmonic function Carleman's formula Nevanlinna's representation for halfsphere lower bound
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A New Class of Harmonic Univalent Functions 被引量:2
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作者 LI Shu-hai MA Li-na 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第2期286-292,共7页
A complex-valued harmonic function that is univalent and sense preserving in the unit disk U can be written in the form of f = h + g,where h and g are analytic in U.We define and investigate a new class LH_λ(α,β) b... A complex-valued harmonic function that is univalent and sense preserving in the unit disk U can be written in the form of f = h + g,where h and g are analytic in U.We define and investigate a new class LH_λ(α,β) by generalized Salagean operator of harmonic univalent functions.We give sufficient coefficient conditions for normalized harmonic functions in the class LH_λ(α,β).These conditions are also shown to be necessary when the coefficients are negative.This leads to distortion bounds and extreme points. 展开更多
关键词 harmonic function Salagean operator extreme points distortion bounds
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Abnormal transition of the electron energy distribution with excitation of the second harmonic in low-pressure radio-frequency capacitively coupled plasmas
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作者 余乐怡 陆文琪 张丽娜 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第8期58-63,共6页
The self-excited second harmonic in radio-frequency capacitively coupled plasma was significantly enhanced by adjusting the external variable capacitor.At a lower pressure of 3 Pa,the excitation of the second harmonic... The self-excited second harmonic in radio-frequency capacitively coupled plasma was significantly enhanced by adjusting the external variable capacitor.At a lower pressure of 3 Pa,the excitation of the second harmonic caused an abnormal transition of the electron energy probability function,resulting in abrupt changes in the electron density and temperature.Such changes in the electron energy probability function as well as the electron density and temperature were not observed at the higher pressure of 16 Pa under similar harmonic changes.The phenomena are related to the influence of the second harmonic on stochastic heating,which is determined by both amplitude and the relative phase of the harmonics.The results suggest that the self-excited high-order harmonics must be considered in practical applications of lowpressure radio-frequency capacitively coupled plasmas. 展开更多
关键词 RADIO-FREQUENCY capacitively coupled plasma harmonicS the electron energy probability function
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High-Order Radial Derivatives of Harmonic Function and Gravity Anomaly 被引量:8
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作者 Ziqing Wei 《Journal of Physical Science and Application》 2014年第7期454-467,共14页
The first through ninth radial derivatives of a harmonic function and gravity anomaly are derived in this paper. These derivatives can be used in the analytical continuation application. For the downward continuation ... The first through ninth radial derivatives of a harmonic function and gravity anomaly are derived in this paper. These derivatives can be used in the analytical continuation application. For the downward continuation of gravity anomaly, the Taylor series approach developed in the paper is equivalent theoretically to but more efficient and storage-saving computationally than the well-known gradient operator approach. Numerical simulation shows that Taylor series expansion constructed by the derived formulas for the radial derivatives of gravity disturbance is still convergent for height up to 4 km. 展开更多
关键词 harmonic function gravity anomaly gravity disturbance high-order radial derivative analytical continuation.
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Several Hermite-Hadamard Type Inequalities for Harmonically Convex Functions in the Second Sense with Applications 被引量:1
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作者 Wang Wen Yang Shi-guo Liu Xue-ying 《Communications in Mathematical Research》 CSCD 2016年第2期105-110,共6页
In this paper, we first introduce the concept "harmonically convex functions" in the second sense and establish several Hermite-Hadamard type inequalities for harmonically convex functions in the second sense. Final... In this paper, we first introduce the concept "harmonically convex functions" in the second sense and establish several Hermite-Hadamard type inequalities for harmonically convex functions in the second sense. Finally, some applications to special mean are shown. 展开更多
关键词 Hermite-Hadamard's inequality harmonically convex function mean inequality
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Modeling, Steady-State Analysis of a SEPIC dc-dc Converter Based on Switching Function and Harmonic Balance Technique 被引量:1
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作者 Ajayi Samuel Taiwo Joseph Yakubu Oricha 《Journal of Power and Energy Engineering》 2014年第4期704-711,共8页
The paper presents modeling approach of a Single Ended Primary Inductance Converter (SEPIC) system. The complete model derivation of the SEPIC converter system has been presented in different modes of operation. Stead... The paper presents modeling approach of a Single Ended Primary Inductance Converter (SEPIC) system. The complete model derivation of the SEPIC converter system has been presented in different modes of operation. Steady state and small signal analysis was carried out on the converter dynamic equations using the method of Harmonic balance Technique. The steady state variables and their respective ripple quantities obtained were plotted against duty ratio D. The results obtained for a supply input voltage of 60 volts to the converter at a duty ratio of D = 0.8 , compares well with simulation results. 展开更多
关键词 SEPIC CONVERTER SWITCHING function harmonic BALANCE TECHNIQUE
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Investigation on the relationship between overpressure and sub-harmonic response from encapsulated microbubbles 被引量:2
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作者 吴军 范庭波 +1 位作者 许迪 章东 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第10期268-274,共7页
Sub-harmonic component generated from microbubbles is proven to be potentially used in noninvasive blood pressure measurement. Both theoretical and experimental studies are performed in the present work to investigate... Sub-harmonic component generated from microbubbles is proven to be potentially used in noninvasive blood pressure measurement. Both theoretical and experimental studies are performed in the present work to investigate the dependence of the sub-harmonic generation on the overpressure with different excitation pressure amplitudes and pulse lengths. With 4-MHz ultrasound excitation at an applied acoustic pressure amplitude of 0.24 MPa, the measured sub-harmonic amplitude exhibits a decreasing change as overpressure increases; while non-monotonic change is observed for the applied acoustic pressures of 0.36 MPa and 0.48 MPa, and the peak position in the curve of the sub-harmonic response versus the overpres- sure shifts toward higher overpressure as the excitation pressure amplitude increases. Furthermore, the exciting pulse with long duration could lead to a better sensitivity of the sub-harmonic response to overpressure. The measured results are ex- plained by the numerical simulations based on the Marmottant model. The numerical simulations qualitatively accord with the measured results. This work might provide a preliminary proof for the optimization of the noninvasive blood pressure measurement through using sub-harmonic generation from microbubbles. 展开更多
关键词 MICROBUBBLE OVERPRESSURE sub-harmonic response blood pressure measurement
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Generalized Harmonic Numbers Hn,k,r (α,β) with Combinatorial Sequences 被引量:1
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作者 Rui Wang   Wuyungaowa 《Journal of Applied Mathematics and Physics》 2022年第5期1602-1618,共17页
In this paper, we observe the generalized Harmonic numbers H<sub>n,k,r</sub> (α,β). Using generating function, we investigate some new identities involving generalized Harmonic numbers H<sub>n,k,r&... In this paper, we observe the generalized Harmonic numbers H<sub>n,k,r</sub> (α,β). Using generating function, we investigate some new identities involving generalized Harmonic numbers H<sub>n,k,r</sub> (α,β) with Changhee sequences, Daehee sequences, Degenerate Changhee-Genoocchi sequences, Two kinds of degenerate Stirling numbers. Using Riordan arrays, we explore interesting relations between these polynomials, Apostol Bernoulli sequences, Apostol Euler sequences, Apostol Genoocchi sequences. 展开更多
关键词 Generating function Riordan Arrays Generalized harmonic Numbers Changhee Sequences Daehee Sequences Apostol Bernoulli Sequences Degenerate Changhee-Genoocchi Sequences
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A Broadband 630-720 GHz Schottky Based Sub-Harmonic Mixer Using Intrinsic Resonances of Hammer-Head Filter 被引量:1
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作者 Yue He Yaoling Tian +2 位作者 Li Miao Jun Jiang XianJin Deng 《China Communications》 SCIE CSCD 2019年第2期76-84,共9页
An room temperature low noise anti-parallel Schottky diode based 630-720 GHz sub-harmonic mixer(SHM) is designed, built and measured. Intrinsic resonances in lowpass hammer-head filter have been adopted to prevent the... An room temperature low noise anti-parallel Schottky diode based 630-720 GHz sub-harmonic mixer(SHM) is designed, built and measured. Intrinsic resonances in lowpass hammer-head filter have been adopted to prevent the LO and RF power leak from the IF channel, while greatly minimizing the transmission line size. The mixer consists of 15 um quartz terahertz circuit and 127 um Al2 O3 IF transformer circuit. An improved lumped element equivalent noise model of SBDs guarantees the accuracy of simulation. The measurement indicates that with local oscillating(LO)signal of 2-8 mW, the lowest double sideband(DSB) conversion loss is 8.2 dB at 645 GHz,and the best DSB noise temperature is 2800 K at 657 GHz. The 3 dB bandwidth of conversion loss is 75 GHz from 638 to 715 GHz. The work IF frequency band is above 20 GHz ranging from 1 to 20 GHz with-10 dB return loss. 展开更多
关键词 erahertz sub-harmonic MIXER hammer-head FILTER SCHOTTKY diode
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GRADIENT ESTIMATES FOR POSITIVE SMOOTH f-HARMONIC FUNCTIONS 被引量:3
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作者 陈立 陈文艺 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1614-1618,共5页
For Riemannian manifolds with a measure, we study the gradient estimates for positive smooth f-harmonic functions when the ∞-Bakry-Emery Ricci tensor and Ricci tensor are bounded from below, generalizing the classica... For Riemannian manifolds with a measure, we study the gradient estimates for positive smooth f-harmonic functions when the ∞-Bakry-Emery Ricci tensor and Ricci tensor are bounded from below, generalizing the classical ones of Yau (i.e., when : is constant). 展开更多
关键词 gradient estimate f-harmonic function Bakry-Emery Ricci tensor
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ON THE DIMENSIONS OF SPACES OF HARMONIC FUNCTIONS WITH POLYNOMIAL GROWTH
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作者 Xiantao HUANG 《Acta Mathematica Scientia》 SCIE CSCD 2019年第5期1219-1234,共16页
In this paper, we obtain an estimate for the lower bound for the dimensions of harmonic functions with polynomial growth and a Liouville type theorem on manifolds with nonnegative Ricci curvature whose tangent cone at... In this paper, we obtain an estimate for the lower bound for the dimensions of harmonic functions with polynomial growth and a Liouville type theorem on manifolds with nonnegative Ricci curvature whose tangent cone at infinity is a unique metric cone with a conic measure. 展开更多
关键词 RICCI CURVATURE harmonic function with POLYNOMIAL growth EIGENVALUE
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A SCHWARZ LEMMA FOR HARMONIC FUNCTIONS IN THE REAL UNIT BALL
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作者 Shaoyu DAI Huaihui CHEN 《Acta Mathematica Scientia》 SCIE CSCD 2019年第5期1339-1344,共6页
We establish a precise Schwarz lemma for real-valued and bounded harmonic functions in the real unit ball of dimension n. This extends Chen's Schwarz-Pick lemma for real-valued and bounded planar harmonic mapping.
关键词 harmonic functionS Schwarz-Pick LEMMA unit BALL
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CONSTRUCTION SPACE HARMONIC FUNCTIONS IN POLYN0MIAL FORM AND SPHERICAL FUNCTIONS BY COMPLEX-FUNCTIONAL
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作者 王其申 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第9期877-881,共5页
In this paper, applying the theory of complex-functional, not only the spaceharmonic functions in polynomial form. but aIso the spherical functions are obtained.
关键词 complex-functional harmonic functions spherical functions
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NUMERICAL COMPARISON OF TWO BOUNDARY ELEMENT METHODS FOR PLANE HARMONIC FUNCTIONS
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作者 何文军 丁皓江 胡海昌 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1993年第4期312-319,共8页
A direct boundary element method (BEM) has been studied in the paper based on a set of sufficient and necessary boundary integral equations (BIE) for the plane harmonic functions. The new sufficient and necessary BEM ... A direct boundary element method (BEM) has been studied in the paper based on a set of sufficient and necessary boundary integral equations (BIE) for the plane harmonic functions. The new sufficient and necessary BEM leads to accurate results while the conventional insufficient BEM will lead to inaccurate results when the conventional BIE has multiple solutions. Theoretical and numerical analyses show that it is beneficial to use the sufficient and necessary BEM, to avoid hidden dangers due to non-unique solution of the conventional BIE. 展开更多
关键词 boundary integral equation BEM plane harmonic functions
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Investigation of analytical harmonic frequency and potential energy function, vibrational levels for the X^2∑^+ and A^2Л states of CN radical
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作者 Wang Jian-Kun Wu Zhen-Sen 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第8期2919-2924,共6页
This paper calculates the equilibrium structure and the potential energy functions of the ground state (X^2∑^+) and the low lying excited electronic state (A^2Л) of CN radical are calculated by using CASSCF met... This paper calculates the equilibrium structure and the potential energy functions of the ground state (X^2∑^+) and the low lying excited electronic state (A^2Л) of CN radical are calculated by using CASSCF method. The potential energy curves are obtained by a least square fitting to the modified Murrell-Sorbie function. On the basis of physical theory of potential energy function, harmonic frequency (ωe) and other spectroscopic constants (ωeχe, βe and αe) are calculated by employing the Rydberg-Klei-Rees method. The theoretical calculation results are in excellent agreement with the experimental and other complicated theoretical calculation data. In addition, the eigenvalues of vibrational levels have been calculated by solving the radial one-dimensional SchrSdinger equation of nuclear motion using the algebraic method based on the analytical potential energy function. 展开更多
关键词 potential energy function harmonic frequency vibrational levels algebraic method
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