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Non-symmetric differentially subordinate martingales and sharp weak-type bounds for Fourier multipliers
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作者 Meryem Akboudj Yong Jiao Adam Osękowski 《Science China Mathematics》 SCIE CSCD 2024年第8期1807-1826,共20页
Let p>2 be a given exponent.In this paper,we prove,with the best constant,the weak-type(p,p)inequality■for a large class of non-symmetric Fourier multipliers T_(m) obtained via modulation of jumps of certain L... Let p>2 be a given exponent.In this paper,we prove,with the best constant,the weak-type(p,p)inequality■for a large class of non-symmetric Fourier multipliers T_(m) obtained via modulation of jumps of certain Lévy processes.In particular,the estimate holds for appropriate linear combinations of second-order Riesz transforms and skew versions of the Beurling-Ahlfors operator on the complex plane.The proof rests on a novel probabilistic bound for Hilbert-space-valued martingales satisfying a certain non-symmetric subordination principle.Further applications to harmonic functions and Riesz systems on Euclidean domains are indicated. 展开更多
关键词 weak-type bound Fourier multiplier MARTINGALE differential subordination laminate
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New Universal Bounds for Eigenvalues of the Markov Diffusion Operator L2
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作者 Yanli LI Feng DU 《Journal of Mathematical Research with Applications》 2025年第6期745-757,共13页
In this paper,we study the eigenvalue problem of the Markov diffusion operator L^(2),and give generalized inequalities for eigenvalues of the operator L^(2)on a Markov diffusion triple.By applying these inequalities,w... In this paper,we study the eigenvalue problem of the Markov diffusion operator L^(2),and give generalized inequalities for eigenvalues of the operator L^(2)on a Markov diffusion triple.By applying these inequalities,we then get some new universal bounds for eigenvalues of a special Markov diffusion operator L^(2)on bounded domains in an Euclidean space.Moreover,our results can reveal the relationship between the(k+1)-th eigenvalue and the first k eigenvalues in a relatively straightforward manner. 展开更多
关键词 Markov diffusion operator EIGENVALUES universal bounds Markov diffusion triple
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The Estimation for Lower Bounds of the Solutions of Fermat's Equation
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作者 乐茂华 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期52-55,共4页
Let p be a prime with p≡3(mod 4). In this paper,by using some results relate the representation of integers by primitive binary quadratic forms,we prove that if x,y,z are positive integers satisfying x^p+y^p=z^p, p|x... Let p be a prime with p≡3(mod 4). In this paper,by using some results relate the representation of integers by primitive binary quadratic forms,we prove that if x,y,z are positive integers satisfying x^p+y^p=z^p, p|xyz, x<y<z, then y>p^(6p-2)/2. 展开更多
关键词 Fermat's last theorem integer solution lower bound
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LOWER BOUNDS ESTIMATE FOR THE BLOW-UP TIME OF A NONLINEAR NONLOCAL POROUS MEDIUM EQUATION 被引量:20
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作者 刘灯明 穆春来 辛巧 《Acta Mathematica Scientia》 SCIE CSCD 2012年第3期1206-1212,共7页
The lower bounds for the blow-up time of blow-up solutions to the nonlinear nolocal porous equation ut=△u^m+u^p∫Ωu^qdxwith either null Dirichlet boundary condition or homogeneous Neumann boundary condi- tion is g... The lower bounds for the blow-up time of blow-up solutions to the nonlinear nolocal porous equation ut=△u^m+u^p∫Ωu^qdxwith either null Dirichlet boundary condition or homogeneous Neumann boundary condi- tion is given in this article by using a differential inequality technique. 展开更多
关键词 Lower bounds blow-up time Dirichlet boundary condition Neumann boundary condition
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LIMITING WEAK-TYPE BEHAVIORS FOR CERTAIN LITTLEWOOD-PALEY FUNCTIONS 被引量:2
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作者 Xianming HOU Huoxiong WU 《Acta Mathematica Scientia》 SCIE CSCD 2019年第1期11-25,共15页
In this paper, we establish the following limiting weak-type behaviors of Littlewood-Paley g-function g_φ: for nonnegative function f∈ L^1(R^n),■and ■where f_t(x) =t^(-n)f(t^(-1) x) for t > 0. Meanwhile, the co... In this paper, we establish the following limiting weak-type behaviors of Littlewood-Paley g-function g_φ: for nonnegative function f∈ L^1(R^n),■and ■where f_t(x) =t^(-n)f(t^(-1) x) for t > 0. Meanwhile, the corresponding results for Marcinkiewicz integral and its fractional version with kernels satisfying L_α~q-Dini condition are also given. 展开更多
关键词 LIMITING BEHAVIORS weak-type bounds LITTLEWOOD-PALEY g-functions Marcinkiewicz integrals L_α~q -Dini conditions
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Performance gain bounds of coherently combining multiple radars in a target-based calibration manner 被引量:4
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作者 LIU Xinghua XU Zhenhai XIAO Shunping 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第2期278-287,共10页
To achieve a high signal-to-noise ratio(SNR) while maintaining moderate radar antenna, a target-based calibration manner is available to coherently combine multiple radars. The key to this calibration manner is to est... To achieve a high signal-to-noise ratio(SNR) while maintaining moderate radar antenna, a target-based calibration manner is available to coherently combine multiple radars. The key to this calibration manner is to estimate coherence parameters(CPs), i.e., time and phase calibration values in transmission and reception estimation, by separating the target returns into monostatic and bistatic echoes. However, CPs estimations exist uncertainties, which will affect the performance gain after multiradar coherent combination. The principle of coherently combining multiple radars is elaborated and the signal probability model for CPs estimation is established. On this basis, CPs Cramer-Rao bound(CRB) is derived in the closed-form, according to which the non-tight and tight upper bounds for multiple radars coherent combination performance gain are derived in the closed-form and via Monte Carlo(MC) simulations, respectively. Simulations validate the correctness of the derived CRB and gain bounds. 展开更多
关键词 coherently COMBINING MULTIPLE radars Cramer-Rao bound (CRB) coherence gain
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NEW LOWER BOUNDS FOR LEE DISCREPANCY ON TWO AND THREE MIXED LEVELS FACTORIALS 被引量:3
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作者 宋硕 张琼慧 +1 位作者 邹娜 覃红 《Acta Mathematica Scientia》 SCIE CSCD 2016年第6期1832-1840,共9页
The objective of this paper is to study the issue of uniformity on asymmetrical designs with two and three mixed levels in terms of Lee discrepancy. Based on the known formulation, we present a new lower bound of Lee ... The objective of this paper is to study the issue of uniformity on asymmetrical designs with two and three mixed levels in terms of Lee discrepancy. Based on the known formulation, we present a new lower bound of Lee discrepancy of fractional factorial designs with two and three mixed levels. Our new lower bound is sharper and more valid than other existing lower bounds in literature, which is a useful complement to the lower bound theory of discrepancies. 展开更多
关键词 U-type design Lee discrepancy uniform design lower bound
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TWO-WEIGHT WEAK-TYPE MAXIMAL INEQUALITIES FOR MARTINGALES 被引量:4
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作者 任颜波 侯友良 《Acta Mathematica Scientia》 SCIE CSCD 2009年第2期402-408,共7页
In this article, some necessary and sufficient conditions are shown in order that the inequality of the form Ф1(λ)Pu(f^*〉λ)≤Ev (Ф2(C|f∞|)) holds with some constant C 〉 0 independent of martingale f... In this article, some necessary and sufficient conditions are shown in order that the inequality of the form Ф1(λ)Pu(f^*〉λ)≤Ev (Ф2(C|f∞|)) holds with some constant C 〉 0 independent of martingale f = (fn)n≥0 and λ 〉 0, where Фl and Ф2 are a pair of Young functions, f^*=sup n≥0|fn| adn f∞=lim n→∞ fn a.e. 展开更多
关键词 MARTINGALE WEIGHT weak-type inequality Young function
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LOWER BOUNDS OF BLOW UP TIME FOR A SYSTEM OF SEMI-LINEAR HYPERBOLIC PETROVSKY EQUATIONS 被引量:2
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作者 Amir PEYRAVI 《Acta Mathematica Scientia》 SCIE CSCD 2016年第3期683-688,共6页
Li et al. in [3] obtained blow-up results for a system of Petrovskey equations in some different cases. In this article we obtain lower bounds for the blow up time under some considerations on initial data.
关键词 lower bound blow up Petrovsky systems
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Some Estimates for Commutators of Fractional Integrals Associated to Operators with Gaussian Kernel Bounds on Weighted Morrey Spaces 被引量:3
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作者 Hua Wang 《Analysis in Theory and Applications》 2013年第1期72-85,共14页
Let L be the infinitesimal generator of an analytic semigroup on L^2 (R^n) with Gaussian kernel bound, and let L^-α/2 be the fractional integrals of L for 0 〈 α 〈 n. In this paper, we will obtain some boundedn... Let L be the infinitesimal generator of an analytic semigroup on L^2 (R^n) with Gaussian kernel bound, and let L^-α/2 be the fractional integrals of L for 0 〈 α 〈 n. In this paper, we will obtain some boundedness properties of commutators [b, L^-α/2] on weighted Morrey spaces L^p,k(w) when the symbol b belongs to BMO(Rn) or the homogeneous Lipschitz space. 展开更多
关键词 Gaussian upper bound fractional integral weighted Morrey space commutator.
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Best bounds on the distance between 3-direction quartic box spline surface and its control net 被引量:2
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作者 ZENG Xiao-ming ZHOU Guo-rong YANG Lian-qiang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2013年第2期147-157,共11页
We present the best bounds on the distance between 3-direction quartic box spline surface patch and its control net by means of analysis and computing for the basis functions of 3-direction quartic box spline surface.... We present the best bounds on the distance between 3-direction quartic box spline surface patch and its control net by means of analysis and computing for the basis functions of 3-direction quartic box spline surface.Both the local bounds and the global bounds are given by the maximum norm of the first differences or second differences or mixed differences of the control points of the surface patch. 展开更多
关键词 Box spline bound parametric surface basis function differences of control point.
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LOWER BOUNDS ON THE MAXIMUM GENUS OF LOOPLESS MULTIGRAPHS 被引量:1
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作者 LiDeming LiuYanpei 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2000年第4期359-368,共10页
The lower bounds on the maximum genus of loopless graphs are obtained according to the connectivity of these graphs. This not only answers a question of Chen, Archdeacon and Gross, but also generalizes the previous kn... The lower bounds on the maximum genus of loopless graphs are obtained according to the connectivity of these graphs. This not only answers a question of Chen, Archdeacon and Gross, but also generalizes the previous known results. Thus, a picture of the lower bounds on the maximum genus of loopless multigraphs is presented. 展开更多
关键词 Maximum genus lower bound multigraph.
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Sharp upper bounds for the adjacency and the signless Laplacian spectral radius of graphs 被引量:1
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作者 WU Xian-zhang LIU Jian-ping 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2019年第1期100-112,共13页
Let G be a simple graph with n vertices and m edges. In this paper, we present some new upper bounds for the adjacency and the signless Laplacian spectral radius of graphs in which every pair of adjacent vertices has ... Let G be a simple graph with n vertices and m edges. In this paper, we present some new upper bounds for the adjacency and the signless Laplacian spectral radius of graphs in which every pair of adjacent vertices has at least one common adjacent vertex. Our results improve some known upper bounds. The main tool we use here is the Lagrange identity. 展开更多
关键词 graph SPECTRAL RADIUS signless LAPLACIAN SPECTRAL RADIUS upper bound
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MIMO Capacity Bounds with Doubly Correlated Rician Channel in Geometrical Channel Model 被引量:2
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作者 Li Yonghua He Zhiqiang Lv Tiejun Lin Jiaru 《China Communications》 SCIE CSCD 2010年第5期9-13,共5页
MIMO system can provide higher capacity in independent conditions. When the spatial-temporal fading correlation exists, the capacity may decrease. In this paper, the geometrical MIMO channel model is presented with Ri... MIMO system can provide higher capacity in independent conditions. When the spatial-temporal fading correlation exists, the capacity may decrease. In this paper, the geometrical MIMO channel model is presented with Rician factor. Based on the MIMO ergodic capacity, the capacity bounds are derived with arbitrary finite number of antennas. The bounds are derived in the exact expressions in doubly correlated MIMO R/clan channel. Then a simple expression for the capacity bounds is attained for the high SNR. Finally, the tightness of derived bounds is verified by Monte Carlo simulation. 展开更多
关键词 MIMO RICIAN capacity bounds
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A NEW METHOD FOR ESTIMATING BOUNDS OF EIGENVALUES 被引量:1
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作者 Yang Xiaowei Chen Suhuan +1 位作者 Lian Huadong Yang Guang 《Acta Mechanica Solida Sinica》 SCIE EI 2001年第3期242-250,共9页
A new method for estimating the bounds of eigenvalues ispresented. In order to show that the method proposed is as effectiveas Qiu's an undamping spring-mass system with 5 nodes and 5 degrees ofreedom is given. To... A new method for estimating the bounds of eigenvalues ispresented. In order to show that the method proposed is as effectiveas Qiu's an undamping spring-mass system with 5 nodes and 5 degrees ofreedom is given. To illustrate that the present method can beapplied to structures which cannot be treated by non-negativedecomposition, a plane frame with 202 nodes and 357 beam elements isgiven. The results show that the present method is effective forestimating the bounds of eigenvalues and is more common than Qiu's. 展开更多
关键词 bounds of eigenvalues non-negative decomposition eigenvalue inclusiontheorem
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Lower bounds and modified LPT algorithm for k-partitioning problems with partition matroid constraint 被引量:1
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作者 WU Biao YAO En-yu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第1期1-8,共8页
In this paper, the k-partitioning problem with partition matroid constraint is considered. LPT algorithm is modified to fit the problem and its worst-ease performance is analyzed. The lower bounds of optimal solution ... In this paper, the k-partitioning problem with partition matroid constraint is considered. LPT algorithm is modified to fit the problem and its worst-ease performance is analyzed. The lower bounds of optimal solution for the min-max problem are given. 展开更多
关键词 partitioning constrained partition lower bound worst case ratio
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The Relationship between Energy Consumption and Economic Growth in the USA: A Non-Linear ARDL Bounds Test Approach 被引量:1
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作者 Arzu Tay Bayramoglu Ertugrul Yildirim 《Energy and Power Engineering》 2017年第3期170-186,共17页
We study the relationship between energy consumption and economic growth in the case of USA by using an asymmetric ARDL bounds test approach to achieve the actual model. The quarterly data set covers the period of 197... We study the relationship between energy consumption and economic growth in the case of USA by using an asymmetric ARDL bounds test approach to achieve the actual model. The quarterly data set covers the period of 1973:1- 2013:4. The findings indicate that the effect of energy consumption is asymmetric in the long term but not in the short term. In the long run, the effect of negative component of energy consumption on economic growth is small and statistically insignificant. The coefficient of the positive component of energy consumption is found about 0.9 and statistically significant at 1% level. We conclude that energy saving policies such as technological progress and organizational rearrangements may have the dimmer effect for the impact of a negative component of energy consumption and the booster effect for impact of the positive component of energy consumption. Thus, energy saving policy should be tightly followed by the goal of high economic growth. 展开更多
关键词 Energy CONSUMPTION Economic Growth NON-LINEAR ARDL bounds Test USA
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Bounds for the Zeros of a Polynomial with Restricted Coefficients 被引量:1
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作者 Abdul Aziz Bashir Ahmad Zargar 《Applied Mathematics》 2012年第1期30-33,共4页
In this paper we shall obtain some interesting extensions and generalizations of a well-known theorem due to Enestrom and Kakeya according to which all the zeros of a polynomial P(Z =αnZn+...+α1Z+α0satisfying the r... In this paper we shall obtain some interesting extensions and generalizations of a well-known theorem due to Enestrom and Kakeya according to which all the zeros of a polynomial P(Z =αnZn+...+α1Z+α0satisfying the restriction αn≥αn-1≥...≥α1≥α0≥0 lie in the closed unit disk. 展开更多
关键词 POLYNOMIAL bounds ZEROS
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ELEMENTARY DENSITY BOUNDS FOR SELF-SIMILAR SETS AND APPLICATION 被引量:1
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作者 Shaoyuan Xu Weiyi Su 《Analysis in Theory and Applications》 2007年第4期334-342,共9页
Falconer[1] used the relationship between upper convex density and upper spherical density to obtain elementary density bounds for s-sets at H S-almost all points of the sets. In this paper, following Falconer[1], we ... Falconer[1] used the relationship between upper convex density and upper spherical density to obtain elementary density bounds for s-sets at H S-almost all points of the sets. In this paper, following Falconer[1], we first provide a basic method to estimate the lower bounds of these two classes of set densities for the self-similar s-sets satisfying the open set condition (OSC), and then obtain elementary density bounds for such fractals at all of their points. In addition, we apply the main results to the famous classical fractals and get some new density bounds. 展开更多
关键词 self-similar s-set upper convex density upper spherical density Hausdorff measure elementary density bound
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Bounds of Efficiency at Maximum Power for Normal-, Sub- and Super-Dissipative Carnot-Like Heat Engines 被引量:2
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作者 王洋 涂展春 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第2期175-178,共4页
The Carnot-like heat engines are classified into three types (normal-, sub- and, super-dissipative) accord- ing to relations between the minimum irreversible entropy production in the "isothermal" processes and th... The Carnot-like heat engines are classified into three types (normal-, sub- and, super-dissipative) accord- ing to relations between the minimum irreversible entropy production in the "isothermal" processes and the time for completing those processes. The efficiencies at maximum power of normal-, sub- and super-dissipative Carnot-like heat engines are proved to be bounded between ηc/2 and ηc/ (2 - ηc ), ηc /2 and ηc, 0 and ηc/ (2 - ηc ), respectively. These bounds are also shared by linear, sub- and super-linear irreversible Carnot-like engines [Tu and Wang, Europhys. Left. 98 (2012) 40001] although the dissipative engines and the irreversible ones are inequivalent to each other. 展开更多
关键词 bound efficiency at maximum power heat engine
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