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Charge self-consistent dynamical mean field theory calculations incombination with linear combination of numerical atomic orbitalsframework based density functional theory
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作者 Xin Qu Peng Xu +6 位作者 Zhiyong Liu Jintao Wang Fei Wang Wei Huang Zhongxin Li Weichang Xu Xinguo Ren 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期62-69,共8页
We present a formalism of charge self-consistent dynamical mean field theory(DMFT)in combination with densityfunctional theory(DFT)within the linear combination of numerical atomic orbitals(LCNAO)framework.We implemen... We present a formalism of charge self-consistent dynamical mean field theory(DMFT)in combination with densityfunctional theory(DFT)within the linear combination of numerical atomic orbitals(LCNAO)framework.We implementedthe charge self-consistent DFT+DMFT formalism by interfacing a full-potential all-electron DFT code with threehybridization expansion-based continuous-time quantum Monte Carlo impurity solvers.The benchmarks on several 3d,4fand 5f strongly correlated electron systems validated our formalism and implementation.Furthermore,within the LCANOframework,our formalism is general and the code architecture is extensible,so it can work as a bridge merging differentLCNAO DFT packages and impurity solvers to do charge self-consistent DFT+DMFT calculations. 展开更多
关键词 dynamical mean field theory density functional theory strongly correlated electrons
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On the Equality of Weighted BajratarevićMeans to Quasi-Arithmetic Means
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作者 Yaxun Yang 《Journal of Applied Mathematics and Physics》 2024年第4期1126-1133,共8页
In this paper, we considered the equality problem of weighted Bajraktarević means with weighted quasi-arithmetic means. Using the method of substituting for functions, we first transform the equality problem into solv... In this paper, we considered the equality problem of weighted Bajraktarević means with weighted quasi-arithmetic means. Using the method of substituting for functions, we first transform the equality problem into solving an equivalent functional equation. We obtain the necessary and sufficient conditions for the equality equation. 展开更多
关键词 Bajraktarević means Quasi-Arithmetic means Equality Problem functional Equation
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Half-metallic ferromagneticWeyl fermions related to dynamic correlations in the zinc-blende compound VAs
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作者 Xianyong Ding Haoran Wei +3 位作者 Ruixiang Zhu Xiaoliang Xiao Xiaozhi Wu Rui Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期528-533,共6页
The realization of 100%polarized topologicalWeyl fermions in half-metallic ferromagnets is of particular importance for fundamental research and spintronic applications.Here,we theoretically investigate the electronic... The realization of 100%polarized topologicalWeyl fermions in half-metallic ferromagnets is of particular importance for fundamental research and spintronic applications.Here,we theoretically investigate the electronic and topological properties of the zinc-blende compound VAs,which was deemed as a half-metallic ferromagnet related to dynamic correlations.Based on the combination of density functional theory and dynamical mean field theory,we uncover that the half-metallic ferromagnet VAs exhibits attractive Weyl semimetallic behaviors which are very close to the Fermi level in the DFT+U regime with effect U values ranging from 1.5 eV to 2.5 eV.Meanwhile,we also investigate the magnetization-dependent topological properties;the results show that the change of magnetization directions only slightly affects the positions of Weyl points,which is attributed to the weak spin–orbital coupling effects.The topological surface states of VAs projected on semi-infinite(001)and(111)surfaces are investigated.The Fermi arcs of all Weyl points are clearly visible on the projected Fermi surfaces.Our findings suggest that VAs is a fully spin-polarized Weyl semimetal with many-body correlated effects in the effective U values range from 1.5 eV to 2.5 eV. 展开更多
关键词 density functional theORY WEYL SEMIMETAL dynamical mean field theORY half metallic FERROMAGNET
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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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Influence of Inclusion Shape on Thermoelasto-Plastic Optimun Design of Ceramic Metal Functionally Graded Materials
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作者 王继辉 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2001年第1期19-24,29,共7页
A nonlinear finite element method is applied to observe how inclusion shape influence the thermal response of a ceramic-metal functionally graded material (FGM). The elastic and plastic behaviors of the layers which a... A nonlinear finite element method is applied to observe how inclusion shape influence the thermal response of a ceramic-metal functionally graded material (FGM). The elastic and plastic behaviors of the layers which are two-phase isotropic composites consisting of randomly oriented elastic spheroidal Inclusions and a ductile matrix are predicted by cc mean field method. The prediction results show that inclusion shape has remarkable influence on the overall behavior of the composite. The consequences of the thermal response analysis of the FGM are that the response is dependent on inclusion shape and its composition profile cooperatively and that the plastic behavior of each layer should be taken into account in optimum design of a ceramic-metal FGM. 展开更多
关键词 inclusion shape ceramic-metal functionally graded material mean field method elastoplastic behavior
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Application of Multiple Mean Generational Function Method to Typhoon Prediction over the Western North Pacific
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作者 Qing Chen Shuyun Yang +1 位作者 Yufang Liao Nengjin Chen 《Meteorological and Environmental Research》 CAS 2013年第4期26-28,共3页
[ Objective] The multiple mean generational function (MMGF) method was applied to forecast the annual number of typhoons (TYs) over the Western North Pacific (WNP). [Method]The method yields a number of predicto... [ Objective] The multiple mean generational function (MMGF) method was applied to forecast the annual number of typhoons (TYs) over the Western North Pacific (WNP). [Method]The method yields a number of predictors by mean generational function based on the rolling 50- year data of TYs frequency and sunspot number, and was repeated to generate forecasts year after year by optimal subset regression. [ Result] The results showed a reasonably high predictive ability dudng period 2000 -2010, with an average root mean square (RMSE) value of 1.92 and a mean absolute error (MAE) value of 1.64. [ Conclusion] Although the MMGF method needs further validation in the practical operation, it already has strong potential for the improvement of skill at forecasting annual frequency of TYs in the WNP. 展开更多
关键词 TYPHOONS Multiple mean generational function PREDICTION China
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Investigations into Some Simple Expressions of the Gamma Function in Wind Power Theoretical Estimate by the Weibull Distribution
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作者 Siaka Touré 《Journal of Applied Mathematics and Physics》 2019年第12期2990-3002,共13页
The Weibull distribution is a probability density function (PDF) which is widely used in the study of meteorological data. The statistical analysis of the wind speed v by using the Weibull distribution leads to the es... The Weibull distribution is a probability density function (PDF) which is widely used in the study of meteorological data. The statistical analysis of the wind speed v by using the Weibull distribution leads to the estimate of the mean wind speed , the variance of v around and the mean power density in the wind. The gamma function Γ is involved in those calculations, particularly Γ (1+1/k), Γ (1+2/k) and Γ (1+3/k). The paper reports the use of the Weibull PDF f(v) to estimate the gamma function. The study was performed by looking for the wind speeds related to the maximum values of f(v), v2 f(v) and v3 f(v). As a result, some approximate relationships were obtained for Γ (1+1/k), Γ (1+2/k) and Γ (1+3/k), that use some fitting polynomial functions. Very good agreements were found between the exact and the estimated values of Γ (1+n/k) that can be used for the estimation of the mean wind speed , the variance σ2 of the wind speed v;around the mean speed and the average wind power density. 展开更多
关键词 GAMMA function Weibull Distribution Beta function Mean WIND Speed AVERAGE WIND Power Density
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Invariance of Weighted Bajraktarevic Mean with Respect to the Beckenbach-Gini means
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作者 Qian Zhang 《Journal of Applied Mathematics and Physics》 2018年第12期2453-2460,共8页
Under some conditions on the functions and defined on I, the weighted Bajraktarevi&#263;?mean is given by where . In this paper, we study the invariance of the weighted Bajraktarevi&#263;?mean with respect to ... Under some conditions on the functions and defined on I, the weighted Bajraktarevi&#263;?mean is given by where . In this paper, we study the invariance of the weighted Bajraktarevi&#263;?mean with respect to Beckenbach-Gini means. 展开更多
关键词 Weighted Bajraktarevic Mean Beckenbach-Gini Mean Invariance Equation functional Equation
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Approach to Riemann Hypothesis by Combined Commensurable Step Function Approximation with Bonnet Method
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作者 Alfred Wünsche 《Advances in Pure Mathematics》 2020年第5期201-228,共28页
To the Riemann hypothesis, we investigate first the approximation by step-wise Omega functions Ω(u) with commensurable step lengths u0 concerning their zeros in corresponding Xi functions Ξ(z). They are periodically... To the Riemann hypothesis, we investigate first the approximation by step-wise Omega functions Ω(u) with commensurable step lengths u0 concerning their zeros in corresponding Xi functions Ξ(z). They are periodically on the y-axis with period proportional to inverse step length u0. It is found that they possess additional zeros off the imaginary y-axis and additionally on this axis and vanish in the limiting case u0 → 0 in complex infinity. There remain then only the “genuine” zeros for Xi functions to continuous Omega functions which we call “analytic zeros” and which lie on the imaginary axis. After a short repetition of the Second mean-value (or Bonnet) approach to the problem and the derivation of operational identities for Trigonometric functions we give in Section 8 a proof for the position of these genuine “analytic” zeros on the imaginary axis by construction of a contradiction for the case off the imaginary axis. In Section 10, we show by a few examples that monotonically decreasing of the Omega functions is only a sufficient condition for the mentioned property of the positions of zeros on the imaginary axis but not a necessary one. 展开更多
关键词 RIEMANN Zeta function RIEMANN Xi function Second Mean-Value APPROACH (Bonnet Method) Chebyshev Polynomials BESSEL functions
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A Number Theoretic Function and Its Mean Value Computation 被引量:1
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作者 李海龙 杨倩丽 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期53-56,共4页
Let p be a prime, n be any positiv e integer, α(n,p) denotes the power of p in the factorization of n! . In this paper, we give an exact computing formula of the mean value ∑ n<Nα(n,p).
关键词 number theoretic function mean value computing formula
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基于改进K-means的局部离群点检测方法
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作者 周玉 夏浩 +1 位作者 岳学震 王培崇 《工程科学与技术》 EI CAS CSCD 北大核心 2024年第4期66-77,共12页
离群点检测任务是指检测与正常数据在特征属性上存在显著差异的异常数据。大多数基于聚类的离群点检测方法主要从全局角度对数据集中的离群点进行检测,而对局部离群点的检测性能较弱。基于此,本文通过引入快速搜索和发现密度峰值方法改... 离群点检测任务是指检测与正常数据在特征属性上存在显著差异的异常数据。大多数基于聚类的离群点检测方法主要从全局角度对数据集中的离群点进行检测,而对局部离群点的检测性能较弱。基于此,本文通过引入快速搜索和发现密度峰值方法改进K-means聚类算法,提出了一种名为KLOD(local outlier detection based on improved K-means and least-squares methods)的局部离群点检测方法,以实现对局部离群点的精确检测。首先,利用快速搜索和发现密度峰值方法计算数据点的局部密度和相对距离,并将二者相乘得到γ值。其次,将γ值降序排序,利用肘部法则选择γ值最大的k个数据点作为K-means聚类算法的初始聚类中心。然后,通过K-means聚类算法将数据集聚类成k个簇,计算数据点在每个维度上的目标函数值并进行升序排列。接着,确定数据点的每个维度的离散程度并选择适当的拟合函数和拟合点,通过最小二乘法对升序排列的每个簇的每1维目标函数值进行函数拟合并求导,以获取变化率。最后,结合信息熵,将每个数据点的每个维度目标函数值乘以相应的变化率进行加权,得到最终的异常得分,并将异常值得分较高的top-n个数据点视为离群点。通过人工数据集和UCI数据集,对KLOD、LOF和KNN方法在准确度上进行仿真实验对比。结果表明KLOD方法相较于KNN和LOF方法具有更高的准确度。本文提出的KLOD方法能够有效改善K-means聚类算法的聚类效果,并且在局部离群点检测方面具有较好的精度和性能。 展开更多
关键词 离群点检测 K均值聚类 最小二乘法 密度峰值 目标函数值
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Legacy effects of historical woodland changes on contemporary plant functional composition 被引量:1
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作者 Ji-Zhong Wan Chun-Jing Wang 《Forest Ecosystems》 SCIE CSCD 2023年第5期569-578,共10页
Considering the legacy of plant functional composition can help assess ecosystem functions and ecosystem services across different spatial scales under land cover changes.Woody plants likely respond to natural and ant... Considering the legacy of plant functional composition can help assess ecosystem functions and ecosystem services across different spatial scales under land cover changes.Woody plants likely respond to natural and anthropogenic perturbations due to historical events(e.g.,agricultural development),thus contemporary plant functional composition may be explained by historical woodland change,a type of land cover change.We propose that historical woodland changes may have legacy effects on contemporary plant functional composition.Here,we used partial least squares regression and linear mixed model analyses to test this assumption by coupling data on community weighted means(CWM)and community weighted variance(CWV)of vegetation plots and calculating the time of woodland existence across different periods from AD 0 to 2017.We found that the legacy effects of historical land cover changes on CWM and CWV during the existence time of woodland,particularly from AD 0 to 900,were drivers of contemporary plant functional composition at large spatial scales.Furthermore,historical woodland changes can affect contemporary plant functional composition,depending on the biome type.Particularly,the CWM of plant height,seed mass,and seed length showed the strongest correlations with woodland changes from AD 1910 to 2010 in tropics with year-round rain,and the CWM of leaf traits correlated with woodland changes from AD 0 to 1700 in tropics with summer rain.Our study provides the effective evidence on the legacy of historical woodland changes and the effects on contemporary plant functional composition,which is crucial with respect to effective management of plant diversity and assessing ecosystem functions and services from local to global scales over time. 展开更多
关键词 BIOME Community weighted means Global scale Historical woodland Land cover Plant functional trait
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Generalization of the linguistic aggregation operator and its application in decision making 被引量:3
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作者 Jose M. Merigo Anna M. Gil-Lafuente +1 位作者 Ligang Zhou Huayou Chen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期593-603,共11页
A generalization of the linguistic aggregation functions (or operators) is presented by using generalized and quasiarithmetic means. Firstly, the linguistic weighted generalized mean (LWGM) and the linguistic gene... A generalization of the linguistic aggregation functions (or operators) is presented by using generalized and quasiarithmetic means. Firstly, the linguistic weighted generalized mean (LWGM) and the linguistic generalized ordered weighted averaging (LGOWA) operator are introduced. These aggregation functions use linguistic information and generalized means in the weighted average (WA) and in the ordered weighted averaging (OWA) function. They are very useful for uncertain situations where the available information cannot be assessed with numerical values but it is possible to use linguistic assessments. These aggregation operators generalize a wide range of aggregation operators that use linguistic information such as the linguistic generalized mean (LGM), the linguistic OWA (LOWA) operator and the linguistic or- dered weighted quadratic averaging (LOWQA) operator. We also introduce a further generalization by using quasi-arithmetic means instead of generalized means obtaining the quasi-LWA and the quasi-LOWA operator. Finally, we develop an application of the new approach where we analyze a decision making problem regarding the selection of strategies. 展开更多
关键词 linguistic aggregation function linguistic orderedweighted averaging (OWA) operator generalized mean linguis-tic decision making strategic decision making uncertainty.
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The construction and approximation of some neural networks operators 被引量:2
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作者 CHEN Zhi-xiang CAO Fei-long ZHAO Jian-wei 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2012年第1期69-77,共9页
In this paper, the technique of approximate partition of unity is used to construct a class of neural networks operators with sigmoidal functions. Using the modulus of continuity of function as a metric, the errors of... In this paper, the technique of approximate partition of unity is used to construct a class of neural networks operators with sigmoidal functions. Using the modulus of continuity of function as a metric, the errors of the operators approximating continuous functions defined on a compact interval are estimated. Furthmore, Bochner-Riesz means operators of double Fourier series are used to construct networks operators for approximating bivariate functions, and the errors of approximation by the operators are estimated. 展开更多
关键词 APPROXIMATION sigmoidal function neural network operator Bochner-Riesz mean.
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The Asymptotic Property of Generalized Taylor Remainder "Mean Value Point" 被引量:4
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作者 RENLi-shun ZHANGCai-yu 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第3期314-318,共5页
This paper discussed asymptotic property of Taylor remainder 'mean value point' in normed Linear space. The asymptotic progerty of 'mean value point' is solved when f(n+i)(x0)h(n+i) = 0(i = 1, 2,..., p... This paper discussed asymptotic property of Taylor remainder 'mean value point' in normed Linear space. The asymptotic progerty of 'mean value point' is solved when f(n+i)(x0)h(n+i) = 0(i = 1, 2,..., p - 1) and f(n+p)(x0)h(h+p) don't exist. Meanwhile, achieve more general asymptotic estimation formula. Make many former results are just because of special case of the pager. 展开更多
关键词 functionAL F-derivative Gα-derivative mean value point assymptotic property
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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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Evaluating the Brewer–Dobson circulation and its responses to ENSO,QBO,and the solar cycle in different reanalyses 被引量:7
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作者 Jian Rao YueYue Yu +3 位作者 Dong Guo ChunHua Shi Dan Chen DingZhu Hu 《Earth and Planetary Physics》 CSCD 2019年第2期166-181,共16页
This study compares the climatology and long-term trend of northern winter stratospheric residual mean meridional circulation(RMMC), as well as its responses to El Ni?o-Southern Oscillation(ENSO), stratospheric Quasi ... This study compares the climatology and long-term trend of northern winter stratospheric residual mean meridional circulation(RMMC), as well as its responses to El Ni?o-Southern Oscillation(ENSO), stratospheric Quasi Biennial Oscillation(QBO), and solar cycle in ten reanalyses and a stratosphere-resolving model, CESM1-WACCM. The RMMC is a large-scale meridional circulation cell in the stratosphere, usually referred to as the estimate of the Brewer Dobson circulation(BDC). The distribution of the BDC is generally consistent among multiple reanalyses except that the NOAA twentieth century reanalysis(20RC) largely underestimates it. Most reanalyses(except ERA40 and ERA-Interim) show a strengthening trend for the BDC during 1979–2010. All reanalyses and CESM1-WACCM consistently reveal that the deep branch of the BDC is significantly enhanced in El Ni?o winters as more waves from the troposphere dissipate in the stratospheric polar vortex region. A secondary circulation cell is coupled to the temperature anomalies below the QBO easterly center at 50 hPa with tropical upwelling/cooling and midlatitude downwelling/warming, and similar secondary circulation cells also appear between 50–10 hPa and above 10 hPa to balance the temperature anomalies. The direct BDC response to QBO in the upper stratosphere creates a barrier near 30°N to prevent waves from propagating to midlatitudes, contributing to the weakening of the polar vortex. The shallow branch of the BDC in the lower stratosphere is intensified during solar minima, and the downwelling warms the Arctic lower stratosphere. The stratospheric responses to QBO and solar cycle in most reanalyses are generally consistent except in the two 20 CRs. 展开更多
关键词 residual mean meridional stream function(RMMSF) Brewer-Dobson circulation(BDC) El Nino-Southern Oscillation(ENSO) Quasi-Biennial Oscillation(QBO)
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Hyperbolic Fibonacci and Lucas Functions, “Golden” Fibonacci Goniometry, Bodnar’s Geometry, and Hilbert’s Fourth Problem—Part II. A New Geometric Theory of Phyllotaxis (Bodnar’s Geometry) 被引量:2
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作者 Alexey Stakhov Samuil Aranson 《Applied Mathematics》 2011年第2期181-188,共8页
This article refers to the “Mathematics of Harmony” by Alexey Stakhov in 2009, a new interdisciplinary direction of modern science. The main goal of the article is to describe two modern scientific discoveries–New ... This article refers to the “Mathematics of Harmony” by Alexey Stakhov in 2009, a new interdisciplinary direction of modern science. The main goal of the article is to describe two modern scientific discoveries–New Geometric Theory of Phyllotaxis (Bodnar’s Geometry) and Hilbert’s Fourth Problem based on the Hyperbolic Fibonacci and Lucas Functions and “Golden” Fibonacci λ-Goniometry (λ > 0 is a given positive real number). Although these discoveries refer to different areas of science (mathematics and theoretical botany), however they are based on one and the same scientific ideas-the “golden mean,” which had been introduced by Euclid in his Elements, and its generalization—the “metallic means,” which have been studied recently by Argentinian mathematician Vera Spinadel. The article is a confirmation of interdisciplinary character of the “Mathematics of Harmony”, which originates from Euclid’s Elements. 展开更多
关键词 Euclid’s Fifth Postulate Lobachevski’s GEOMETRY HYPERBOLIC GEOMETRY PHYLLOTAXIS Bodnar’s GEOMETRY Hilbert’s Fourth Problem the “Golden” and “Metallic” means Binet Formukas HYPERBOLIC FIBONACCI and Lucas functions Gazale Formulas “Golden” FIBONACCI λ-Goniometry
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Some Hybrid Mean Values of a New Number Theoretic Function 被引量:1
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作者 REN Gang-lian 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期325-329,共5页
Let p and q be two distinct primes, epq(n) denotes the largest exponent of power pq which divides n. In this paper, we study the mean value properties of function epq(n), and give some hybrid mean value formulas f... Let p and q be two distinct primes, epq(n) denotes the largest exponent of power pq which divides n. In this paper, we study the mean value properties of function epq(n), and give some hybrid mean value formulas for epq(n) and Dirichlet divisor function d(n). Key words: largest exponent; asymptotic formula; hybrid mean value; Dirichlet divisor function d(n) 展开更多
关键词 largest exponent asymptotic formula hybrid mean value Dirichlet divisor function d(n)
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THE HADAMARD INEQUALITY FOR CONVEX FUNCTION VIA FRACTIONAL INTEGRALS 被引量:4
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作者 M.E.ZDEMR S.S.DRAGOMIR C.YILDIZ 《Acta Mathematica Scientia》 SCIE CSCD 2013年第5期1293-1299,共7页
In this paper, we establish several inequalities for some differantiable mappings that are connected with the Riemann-Liouville fractional integrals. The analysis used in the proofs is fairly elementary.
关键词 Hadamard's inequality convex functions power-mean inequality Riemann-Liouville fractional integration
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