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Lower bound on BER performance for maximal ratio combining with weighting errors 被引量:1
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作者 盛彬 尤肖虎 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期379-384,共6页
The theoretical lower bounds on mean squared channel estimation errors for typical fading channels are presented by the infinite-length and non-causal Wiener filter and the exact closed-form expressions of the lower b... The theoretical lower bounds on mean squared channel estimation errors for typical fading channels are presented by the infinite-length and non-causal Wiener filter and the exact closed-form expressions of the lower bounds for different channel Doppler spectra are derived. Based on the obtained lower bounds on mean squared channel estimation errors, the limits on bit error rate (BER) for maximal ratio combining (MRC) with Gaussian distributed weighting errors on independent and identically distributed (i. i. d) fading channels are presented. Numerical results show that the BER performances of ideal MRC are the lower bounds on the BER performances of non-ideal MRC and deteriorate as the maximum Doppler frequency increases or the SNR of channel estimate decreases. 展开更多
关键词 lower bound bit error rate minimum mean-square error channel estimation maximal ratio combining
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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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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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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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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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State estimation with quantized innovations in wireless sensor networks: Gaussian mixture estimator and posterior Cramér–Rao lower bound 被引量:2
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作者 Zhang Zhi Li Jianxun +2 位作者 Liu Liu Liu Zhaolei Han Shan 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2015年第6期1735-1746,共12页
Since the features of low energy consumption and limited power supply are very impor- tant for wireless sensor networks (WSNs), the problems of distributed state estimation with quan- tized innovations are investiga... Since the features of low energy consumption and limited power supply are very impor- tant for wireless sensor networks (WSNs), the problems of distributed state estimation with quan- tized innovations are investigated in this paper. In the first place, the assumptions of prior and posterior probability density function (PDF) with quantized innovations in the previous papers are analyzed. After that, an innovative Gaussian mixture estimator is proposed. On this basis, this paper presents a Gaussian mixture state estimation algorithm based on quantized innovations for WSNs. In order to evaluate and compare the performance of this kind of state estimation algo- rithms for WSNs, the posterior Cram6r-Rao lower bound (CRLB) with quantized innovations is put forward. Performance analysis and simulations show that the proposed Gaussian mixture state estimation algorithm is efficient than the others under the same number of quantization levels and the performance of these algorithms can be benchmarked by the theoretical lower bound. 展开更多
关键词 Posterior Cramer-Rao lower bounds Quantiation State estimation Target tracking Wireless sensor network
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A LOWER BOUND APPROACH TO THE YIELD LOCI OF POROUS MATERIALS 被引量:2
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作者 Sun Yi Wang Duo(Department of Applied Mechanics,Harbin Institute of Technology) 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1989年第3期237-243,共7页
A lower bound approach is proposed for the first time to solve the macroscopic yield loci of porous materials.The results are then compared with Gurson's upper bound yield loci and those of the experiments.It is s... A lower bound approach is proposed for the first time to solve the macroscopic yield loci of porous materials.The results are then compared with Gurson's upper bound yield loci and those of the experiments.It is shown that the present analysis is much more in accordance with the experimen- tal results than the Gurson's. 展开更多
关键词 constitutive equations porous materials ductile damage lower bound analysis method
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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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LOWER BOUND LIMIT ANALYSIS OF THREE-DIMENSIONAL ELASTOPLASTIC STRUCTURES BY BOUNDARY ELEMENT METHOD 被引量:1
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作者 刘应华 张晓峰 岑章志 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第12期1466-1474,共9页
Based on the lower bound theorem of limit analysis, a solution procedure for limit analysis of three_dimensional elastoplastic structures was established using conventional boundary element method (BEM). The elastic s... Based on the lower bound theorem of limit analysis, a solution procedure for limit analysis of three_dimensional elastoplastic structures was established using conventional boundary element method (BEM). The elastic stress field for lower bound limit analysis was computed directly by three_dimensional boundary element method (3_D BEM). The self_equilibrium stress field was constructed by the linear combination of several self_equilibrium “basis vectors” which can be computed by elastic_plastic incremental iteration of 3_D BEM analysis. The lower bound limit analysis problem was finally reduced to a series of nonlinear programming sub_problems with relatively few optimal variables. The complex method was used to solve the nonlinear programming sub_problems. The numerical results show that the present solution procedure has good accuracy and high efficiency. 展开更多
关键词 BEM lower bound limit analysis self-equilibrium stress field nonlinear programming complex method
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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 ENERGY CONSERVATIONS AND LOWER BOUNDS FOR POSSIBLE SINGULAR SOLUTIONS TO THE 3D INCOMPRESSIBLE MHD EQUATIONS 被引量:1
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作者 Jae-Myoung KIM 《Acta Mathematica Scientia》 SCIE CSCD 2020年第1期237-244,共8页
In this note,we give a new proof to the energy conservation for the weak solutions of the incompressible 3D MHD equations.Moreover,we give the lower bounds for possible singular solutions to the incompressible 3D MHD ... In this note,we give a new proof to the energy conservation for the weak solutions of the incompressible 3D MHD equations.Moreover,we give the lower bounds for possible singular solutions to the incompressible 3D MHD equations. 展开更多
关键词 MHD EQUATION lower boundS INCOMPRESSIBLE
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Combined load bearing capacity of rigid piles embedded in a crossanisotropic clay deposit using 3D finite element lower bound 被引量:1
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作者 Ardavan Izadi Reza Jamshidi Chenari 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第3期717-737,共21页
In this study,an iterative-based three-dimensional finite element lower bound in association with the second-order cone programming method is adopted to evaluate the limit load of a single pile embedded in cross-aniso... In this study,an iterative-based three-dimensional finite element lower bound in association with the second-order cone programming method is adopted to evaluate the limit load of a single pile embedded in cross-anisotropic soils under general loading condition.The lower bound solutions of the pile embedded in an anisotropic soil deposit can be found by formulating the element equilibrium,equilibrium of shear and normal stresses along discontinuities,boundary conditions,yield function,and optimizing the objective function through the second-order cone programming method in conjunction with an iterative-based update procedure.A general loading condition is considered to profile the expansion of the safe load in the vertical-horizontal-moment(V-H-M)space.The results of this study are compared and validated against three different cases including an isotropic lateral loading,anisotropic end bearing capacity,and a pile embedded in an isotropic soil deposit under general loading condition.A parametric study is conducted to evaluate the impact of different influencing factors.It was found that the effect of anisotropy on the variation of lateral limit load of a single pile is more pronounced than the corresponding vertical and bending moment limit loads,whereas the interface properties have more significant effects on the vertical and bending moment limit loads in comparison to the lateral limit load. 展开更多
关键词 Rigid pile Cross-anisotropy CLAY Combined loading Three-dimensional finite element lower bound
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A Lower and Upper Bound Method for Complex System Reliability Evaluation 被引量:1
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作者 魏展明 周凡 陈耀武 《Journal of Donghua University(English Edition)》 EI CAS 2011年第5期445-450,共6页
It is hard for the existing methods to obtain the expression of the system reliability for most of the practical complex systems with a large number of components and possible stales. A new regression algorithm based ... It is hard for the existing methods to obtain the expression of the system reliability for most of the practical complex systems with a large number of components and possible stales. A new regression algorithm based on the lower and upper bounds is presented in this paper, which can obtain the system reliability analytically without concerning the structure of the complex system. The method has been applied to a real system and the reliability results are compared with those acquired by the classical method and the parametric method. The effectiveness and accuracy of the proposed method have been testified. 展开更多
关键词 RELIABILITY lower bound upper bound regression algorithm
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Lower Bound of Concurrence Based on Generalized Positive Maps 被引量:1
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作者 秦慧慧 费少明 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第12期663-666,共4页
We study the concurrence of arbitrary dimensional bipartite quantum systems. By using a positive but not completely positive map, we present an anaJytical lower bound of concurrence. Detailed examples are used to show... We study the concurrence of arbitrary dimensional bipartite quantum systems. By using a positive but not completely positive map, we present an anaJytical lower bound of concurrence. Detailed examples are used to show that our bound can detect entanglement better and can improve the well known existing lower bounds. 展开更多
关键词 lower bound of concurrence positive maps
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Lower Bounds of Blow Up Time for a Class of Slow Reaction Diffusion Equations with Inner Absorption Terms 被引量:1
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作者 XUE Yingzhen 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2023年第5期373-378,共6页
In this paper,a class of slow reaction-diffusion equations with nonlocal source and inner absorption terms are studied.By using the technique of improved differential inequality,the lower bounds of blow up time for th... In this paper,a class of slow reaction-diffusion equations with nonlocal source and inner absorption terms are studied.By using the technique of improved differential inequality,the lower bounds of blow up time for the system under either homogeneous Dirichlet or nonhomogeneous Neumann boundary conditions are obtained. 展开更多
关键词 slow reaction diffusion equations inner absorption terms lower bounds of blow up time
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AN ASYMPTOTIC-NUMERICAL ANALYSIS FOR THE LOWER BOUND DYNAMIC BUCKLING ESTIMATES
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作者 吴柏生 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1997年第2期165-170,共6页
A finite element asymptotic analysis for determining the lower bound dynamic buckling estimates of imperfection-sensitive structures under step load of infinite duration is presented. The lower bound dynamic buckling ... A finite element asymptotic analysis for determining the lower bound dynamic buckling estimates of imperfection-sensitive structures under step load of infinite duration is presented. The lower bound dynamic buckling loads and the corresponding displacements are sought in the form of asymptotic expansions based on the static stability criterion and they can be determined by solving numerically (FEM) several linear problems with a single nonsingular sub-stiffness matrix. 展开更多
关键词 dynamic buckling lower bound estimate FEM implementation
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Lower bound for the security of differential phase shift quantum key distribution against a one-pulse-attack
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作者 李宏伟 银振强 +3 位作者 王双 鲍皖苏 郭光灿 韩正甫 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第10期46-50,共5页
Quantum key distribution is the art of sharing secret keys between two distant parties, and has attracted a lot of attention due to its unconditional security. Compared with other quantum key distribution protocols, t... Quantum key distribution is the art of sharing secret keys between two distant parties, and has attracted a lot of attention due to its unconditional security. Compared with other quantum key distribution protocols, the differential phase shift quantum key distribution protocol has higher efficiency and simpler apparatus. Unfortunately, the uncondi- tional security of differential phase shift quantum key distribution has not been proved. Utilizing the sharp continuity of the von Neuman entropy and some basic inequalities, we estimate the upper bound for the eavesdropper Eve's infor- mation. We then prove the lower bound for the security of the differential phase shift quantum key distribution protocol against a one-pulse attack with Devatak-Winter's secret key rate formula. 展开更多
关键词 lower bound differential phase shift quantum key distribution
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Area-time associated test cost model for SoC and lower bound of test time
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作者 张金艺 翁寒一 +1 位作者 黄徐辉 蔡万林 《Journal of Shanghai University(English Edition)》 CAS 2011年第1期43-48,共6页
A novel test access mechanism (TAM) architecture with multi test-channel (TC) based on IEEE Standard 1500 is proposed instead of the traditional sub-TAM structure. The cost model of an area-time associated test an... A novel test access mechanism (TAM) architecture with multi test-channel (TC) based on IEEE Standard 1500 is proposed instead of the traditional sub-TAM structure. The cost model of an area-time associated test and the corresponding lower bound of system-on-chip (SoC) test time are established based on this TAM architecture. The model provides a more reliable method to control the SoC scheduling and reduces the complexity in related algorithm research. The result based on the area time associated test cost model has been validated using the ITC02 test benchmark. 展开更多
关键词 system-on-chip design for testability (SoC DriP) test cost test time lower bound
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Lower Bound Limit Analysis of Anisotropic Soils
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作者 Chunguang Li Cuihua Li +1 位作者 Cong Sun Hong Zheng 《Computers, Materials & Continua》 SCIE EI 2018年第1期21-41,共21页
Previous approaches can only tackle anisotropic problems with cohesion varying with direction.A novel linearization of the Mohr-Coulomb yield criterion associated with plane strain problem has been achieved by simulat... Previous approaches can only tackle anisotropic problems with cohesion varying with direction.A novel linearization of the Mohr-Coulomb yield criterion associated with plane strain problem has been achieved by simulating the Mohr’s circle with orientation lines inσ-τspace,which allows for lower bound solution of soils with cohesion and friction coefficient varying with direction.The finite element lower limit analysis formulation using the modified anisotropic yield criterion is then developed.Several examples are given to illustrate the capability and effectiveness of the proposed numerical procedure for computing rigorous lower bounds for anisotropic soils. 展开更多
关键词 Limit analysis lower bound finite element ANISOTROPY
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