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
This paper studies certain estimates for the lower bound of distance between unitary orbits of normal elements.We show that the distance between unitary orbits of normal elements of simple C^(*)-algebras of tracial ra...This paper studies certain estimates for the lower bound of distance between unitary orbits of normal elements.We show that the distance between unitary orbits of normal elements of simple C^(*)-algebras of tracial rank no more than k has a lower bound.Furthermore,if k≤1 and normal elements are commuting,then the lower bound will be better.Another result establishes a connection involving the spectrum distance operator Dc between a C^(*)-algebra of stable rank one C^(*)-algebra and its hereditary C^(*)-subalgebra.展开更多
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
A new quadrilateral edge element method is proposed and analyzed for Maxwell equations.This proposed method is based on Duan-Liang quadrilateral element(Math.Comp.73(2004),pp.1–18).When applied to the eigenvalue prob...A new quadrilateral edge element method is proposed and analyzed for Maxwell equations.This proposed method is based on Duan-Liang quadrilateral element(Math.Comp.73(2004),pp.1–18).When applied to the eigenvalue problem,the method is spectral-correct and spurious-free.Stability and error estimates are obtained,including the interpolation error estimates and the error estimates between the finite element solution and the exact solution.The method is suitable for singular solution as well as smooth solution,and consequently,the method is valid for nonconvex domains which may have a number of reentrant corners.Of course,the method is suitable for arbitrary quadrilaterals(under the usual shape-regular condition).展开更多
As an important resource in data link,time slots should be strategically allocated to enhance transmission efficiency and resist eavesdropping,especially considering the tremendous increase in the number of nodes and ...As an important resource in data link,time slots should be strategically allocated to enhance transmission efficiency and resist eavesdropping,especially considering the tremendous increase in the number of nodes and diverse communication needs.It is crucial to design control sequences with robust randomness and conflict-freeness to properly address differentiated access control in data link.In this paper,we propose a hierarchical access control scheme based on control sequences to achieve high utilization of time slots and differentiated access control.A theoretical bound of the hierarchical control sequence set is derived to characterize the constraints on the parameters of the sequence set.Moreover,two classes of optimal hierarchical control sequence sets satisfying the theoretical bound are constructed,both of which enable the scheme to achieve maximum utilization of time slots.Compared with the fixed time slot allocation scheme,our scheme reduces the symbol error rate by up to 9%,which indicates a significant improvement in anti-interference and eavesdropping capabilities.展开更多
In this article,we show the existence,uniqueness and stability of bounded solutions to the following quasilinear problems with mean curvature operator(φ'(x′(t)))′=f(t,x),t≥t_(0),lim_(t→∞)x(t)=ψ_(0),lim_(t→...In this article,we show the existence,uniqueness and stability of bounded solutions to the following quasilinear problems with mean curvature operator(φ'(x′(t)))′=f(t,x),t≥t_(0),lim_(t→∞)x(t)=ψ_(0),lim_(t→∞)x′(t)e^(t)=0,where t_(0) and ψ_(0) are real constants,φ(s)=s/√1−s^(2),s∈R with s∈(−1,1),f:[t_(0),∞)×R→R satisfies the Lipschitz or Osgood-type conditions.展开更多
The production of light(anti-)nuclei in high-energy collisions has long posed an apparent paradox:How can loosely bound systems such as the anti-deuteron with a binding energy of only 2.23 MeV be formed and survive in...The production of light(anti-)nuclei in high-energy collisions has long posed an apparent paradox:How can loosely bound systems such as the anti-deuteron with a binding energy of only 2.23 MeV be formed and survive in the extreme hot and dense hadronic environment emerging from proton–proton(pp)and heavy-ion collisions,where characteristic thermal energies exceed 100 MeV?A new femtoscopy analysis published on Nature[1]by the ALICE Collaboration at the Large Hadron Collider(LHC)delivers the clearest answer to date.展开更多
The present study investigates the quest for a fully distributed Nash equilibrium(NE) in networked non-cooperative games, with particular emphasis on actuator limitations. Existing distributed NE seeking approaches of...The present study investigates the quest for a fully distributed Nash equilibrium(NE) in networked non-cooperative games, with particular emphasis on actuator limitations. Existing distributed NE seeking approaches often overlook practical input constraints or rely on centralized information. To address these issues, a novel edge-based double-layer adaptive control framework is proposed. Specifically, adaptive scaling parameters are embedded into the edge weights of the communication graph, enabling a fully distributed scheme that avoids dependence on centralized or global knowledge. Every participant modifies its strategy by exclusively utilizing local information and communicating with its neighbors to iteratively approach the NE. By incorporating damping terms into the design of the adaptive parameters, the proposed approach effectively suppresses unbounded parameter growth and consequently guarantees the boundedness of the adaptive gains. In addition, to account for actuator saturation, the proposed distributed NE seeking approach incorporates a saturation function, which ensures that control inputs do not exceed allowable ranges. A rigorous Lyapunov-based analysis guarantees the convergence and boundedness of all system variables. Finally, the presentation of simulation results aims to validate the efficacy and theoretical soundness of the proposed approach.展开更多
Distributions of nuclear magnetic resonance(NMR)relaxation times provide detailed information about the water in wood.This study documents the water dynamics analysis of T_(2)and T_(1)distributions for saturated delig...Distributions of nuclear magnetic resonance(NMR)relaxation times provide detailed information about the water in wood.This study documents the water dynamics analysis of T_(2)and T_(1)distributions for saturated delignified sapwood(DSW),delignified heartwood(DHW)and lignocellulose(LC)samples at different temperatures.Results indicate that below the freezing point of bulk water,free water freezes,causing its signal to disappear from the distribution.Then,the low temperature distributions of the unfrozen bound water contain more information about its components,with DSW,DHW and LC containing two distinct states of bound water(OH bound water(B-water)and more freely bound water(C-water)).Furthermore,it was observed that within the temperature range of−3°C to−60°C,B-water in DSW,DHW and LC maintained a higher unfrozen water content(UWC)value than C-water,and the T_(1)/T_(2)ratios for B-water were consistently higher than that for C-water,indicating that B-water has a greater antifreeze capacity.T_(2)and T_(1)distributions offer different kinds of information about water components,and all peaks within the distribution have been assigned.展开更多
Electron–hole(e–h)recombination is a fundamental process that governs energy dissipation and device efficiency in semiconductors.In two-dimensional(2D)materials,the formation of tightly bound excitons makes exciton-...Electron–hole(e–h)recombination is a fundamental process that governs energy dissipation and device efficiency in semiconductors.In two-dimensional(2D)materials,the formation of tightly bound excitons makes exciton-mediated e–h recombination the dominant decay pathway.In this work,nonradiative e–h recombination within excitons in monolayer MoS_(2) is investigated using first-principles simulations that combine nonadiabatic molecular dynamics with GW and real-time Bethe–Salpeter equation(BSE)propagation.A two-step process is identified:rapid intervalley redistribution induced by exchange interaction,followed by slower phonon-assisted recombination facilitated by exciton binding.By selectively removing the screened Coulomb and exchange terms from the BSE Hamiltonian,their respective contributions are disentangled—exchange interaction is found to increase the number of accessible recombination pathways,while binding reduces the excitation energy and enhances nonradiative decay.A reduction in recombination lifetime by over an order of magnitude is observed due to the excitonic many-body effects.These findings provide microscopic insights for understanding and tuning exciton lifetimes in 2D transition-metal dichalcogenides.展开更多
A scheme is proposed based on a Mach-Zehnder interferometer with high phase sensitivity,utilizing a two-mode squeezed coherent state,generated by four-wave mixing,as input.The phase sensitivity of this scheme easily s...A scheme is proposed based on a Mach-Zehnder interferometer with high phase sensitivity,utilizing a two-mode squeezed coherent state,generated by four-wave mixing,as input.The phase sensitivity of this scheme easily surpasses the Heisenberg limit when intensity difference detection is applied.Under phase-matching conditions,the quantum Cramér-Rao bound significantly exceeds the Heisenberg limit.Additionally,the scheme exhibits robustness against photon loss.When compared with the modified SU(1,1)interferometer with two coherent state inputs,this approach demonstrates superior measurement sensitivity,evaluated through various detection methods and the quantum Cramér-Rao bound.This work holds potential applications in quantum metrology.展开更多
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
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
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
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
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
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.
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
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
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
基金Supported by the Open Research Fund of Key Laboratory of Nonlinear Analysis and Applications(Central China Normal University),Ministry of Education,P.R.China(Grant No.NAA2025ORG011)Science and Technology Plan Project of Jingmen(Grant No.2024YFZD076)+3 种基金Research Team Project of Jingchu University of Technology(Grant No.TD202006)Research Project of Jingchu University of Technology(Grant Nos.HX20240049HX20240200)the Teaching Reform Research Project of Hubei Province(Grant No.2024496)。
文摘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.
基金Supported by Zhejiang Provincial Natural Science Foundation of China(No.ZCLQN25A0103)。
文摘This paper studies certain estimates for the lower bound of distance between unitary orbits of normal elements.We show that the distance between unitary orbits of normal elements of simple C^(*)-algebras of tracial rank no more than k has a lower bound.Furthermore,if k≤1 and normal elements are commuting,then the lower bound will be better.Another result establishes a connection involving the spectrum distance operator Dc between a C^(*)-algebra of stable rank one C^(*)-algebra and its hereditary C^(*)-subalgebra.
文摘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.
基金supported by the National Natural Science Foundation of China(12401482)the second author was supported by the National Natural Science Foundation of China(12371371,12261160361,11971366)supported by the Open Research Fund of Hubei Key Laboratory of Computational Science,Wuhan University.
文摘A new quadrilateral edge element method is proposed and analyzed for Maxwell equations.This proposed method is based on Duan-Liang quadrilateral element(Math.Comp.73(2004),pp.1–18).When applied to the eigenvalue problem,the method is spectral-correct and spurious-free.Stability and error estimates are obtained,including the interpolation error estimates and the error estimates between the finite element solution and the exact solution.The method is suitable for singular solution as well as smooth solution,and consequently,the method is valid for nonconvex domains which may have a number of reentrant corners.Of course,the method is suitable for arbitrary quadrilaterals(under the usual shape-regular condition).
基金supported by the National Science Foundation of China(No.62171387)the Science and Technology Program of Sichuan Province(No.2024NSFSC0468)the China Postdoctoral Science Foundation(No.2019M663475).
文摘As an important resource in data link,time slots should be strategically allocated to enhance transmission efficiency and resist eavesdropping,especially considering the tremendous increase in the number of nodes and diverse communication needs.It is crucial to design control sequences with robust randomness and conflict-freeness to properly address differentiated access control in data link.In this paper,we propose a hierarchical access control scheme based on control sequences to achieve high utilization of time slots and differentiated access control.A theoretical bound of the hierarchical control sequence set is derived to characterize the constraints on the parameters of the sequence set.Moreover,two classes of optimal hierarchical control sequence sets satisfying the theoretical bound are constructed,both of which enable the scheme to achieve maximum utilization of time slots.Compared with the fixed time slot allocation scheme,our scheme reduces the symbol error rate by up to 9%,which indicates a significant improvement in anti-interference and eavesdropping capabilities.
基金Supported by the National Natural Science Foundation of China(Grant Nos.12361040,12061064)the National Science Foundation of Gansu Province(Grant No.22JR5RA264)State Scholarship Fund(Grant No.20230862021).
文摘In this article,we show the existence,uniqueness and stability of bounded solutions to the following quasilinear problems with mean curvature operator(φ'(x′(t)))′=f(t,x),t≥t_(0),lim_(t→∞)x(t)=ψ_(0),lim_(t→∞)x′(t)e^(t)=0,where t_(0) and ψ_(0) are real constants,φ(s)=s/√1−s^(2),s∈R with s∈(−1,1),f:[t_(0),∞)×R→R satisfies the Lipschitz or Osgood-type conditions.
基金supported in part by the National Key Research and Development Project of China(No.2024YFA1612500)the National Natural Science Foundation of China(Nos.12422509,12375121,12547102)。
文摘The production of light(anti-)nuclei in high-energy collisions has long posed an apparent paradox:How can loosely bound systems such as the anti-deuteron with a binding energy of only 2.23 MeV be formed and survive in the extreme hot and dense hadronic environment emerging from proton–proton(pp)and heavy-ion collisions,where characteristic thermal energies exceed 100 MeV?A new femtoscopy analysis published on Nature[1]by the ALICE Collaboration at the Large Hadron Collider(LHC)delivers the clearest answer to date.
基金supported by the National Natural Science Foundation of China (Grant No.62173009)the National Key Research and Development Program of China (Grant No.2021ZD0112302)。
文摘The present study investigates the quest for a fully distributed Nash equilibrium(NE) in networked non-cooperative games, with particular emphasis on actuator limitations. Existing distributed NE seeking approaches often overlook practical input constraints or rely on centralized information. To address these issues, a novel edge-based double-layer adaptive control framework is proposed. Specifically, adaptive scaling parameters are embedded into the edge weights of the communication graph, enabling a fully distributed scheme that avoids dependence on centralized or global knowledge. Every participant modifies its strategy by exclusively utilizing local information and communicating with its neighbors to iteratively approach the NE. By incorporating damping terms into the design of the adaptive parameters, the proposed approach effectively suppresses unbounded parameter growth and consequently guarantees the boundedness of the adaptive gains. In addition, to account for actuator saturation, the proposed distributed NE seeking approach incorporates a saturation function, which ensures that control inputs do not exceed allowable ranges. A rigorous Lyapunov-based analysis guarantees the convergence and boundedness of all system variables. Finally, the presentation of simulation results aims to validate the efficacy and theoretical soundness of the proposed approach.
基金supported by Natural Science Foundation of Inner Mongolia Autonomous Region of China (2023MS03027)the National Natural Science Foundation of China (31860185 and 31160141)
文摘Distributions of nuclear magnetic resonance(NMR)relaxation times provide detailed information about the water in wood.This study documents the water dynamics analysis of T_(2)and T_(1)distributions for saturated delignified sapwood(DSW),delignified heartwood(DHW)and lignocellulose(LC)samples at different temperatures.Results indicate that below the freezing point of bulk water,free water freezes,causing its signal to disappear from the distribution.Then,the low temperature distributions of the unfrozen bound water contain more information about its components,with DSW,DHW and LC containing two distinct states of bound water(OH bound water(B-water)and more freely bound water(C-water)).Furthermore,it was observed that within the temperature range of−3°C to−60°C,B-water in DSW,DHW and LC maintained a higher unfrozen water content(UWC)value than C-water,and the T_(1)/T_(2)ratios for B-water were consistently higher than that for C-water,indicating that B-water has a greater antifreeze capacity.T_(2)and T_(1)distributions offer different kinds of information about water components,and all peaks within the distribution have been assigned.
基金supported by the National Key Research and Development Program of China (Grant Nos.2024YFA1409800 for J.Z.and2024YFA1408603 for Q.Z.)the National Natural Science Foundation of China (Grant Nos.12125408,12334004for J.Z.,and 12174363 for Q.Z.)+1 种基金the Innovation Program for Quantum Science and Technology (Grant No.2021ZD0303306 for J.Z.)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB0450101 for J.Z.)。
文摘Electron–hole(e–h)recombination is a fundamental process that governs energy dissipation and device efficiency in semiconductors.In two-dimensional(2D)materials,the formation of tightly bound excitons makes exciton-mediated e–h recombination the dominant decay pathway.In this work,nonradiative e–h recombination within excitons in monolayer MoS_(2) is investigated using first-principles simulations that combine nonadiabatic molecular dynamics with GW and real-time Bethe–Salpeter equation(BSE)propagation.A two-step process is identified:rapid intervalley redistribution induced by exchange interaction,followed by slower phonon-assisted recombination facilitated by exciton binding.By selectively removing the screened Coulomb and exchange terms from the BSE Hamiltonian,their respective contributions are disentangled—exchange interaction is found to increase the number of accessible recombination pathways,while binding reduces the excitation energy and enhances nonradiative decay.A reduction in recombination lifetime by over an order of magnitude is observed due to the excitonic many-body effects.These findings provide microscopic insights for understanding and tuning exciton lifetimes in 2D transition-metal dichalcogenides.
基金supported by the National Natural Science Foundation of China(Grant Nos.12104190,12104189,12204312)the Natural Science Foundation of Jiangsu Province(Grant No.BK20210874)+2 种基金General project of Natural Science Research in Colleges And Universities of Jiangsu Province(Grant No.20KJB140008)the Jiangxi Provincial Natural Science Foundation(Grant Nos.20224BAB211014 and 20232BAB201042)Key Laboratory of Tian Qin Project(Sun Yat-sen University)。
文摘A scheme is proposed based on a Mach-Zehnder interferometer with high phase sensitivity,utilizing a two-mode squeezed coherent state,generated by four-wave mixing,as input.The phase sensitivity of this scheme easily surpasses the Heisenberg limit when intensity difference detection is applied.Under phase-matching conditions,the quantum Cramér-Rao bound significantly exceeds the Heisenberg limit.Additionally,the scheme exhibits robustness against photon loss.When compared with the modified SU(1,1)interferometer with two coherent state inputs,this approach demonstrates superior measurement sensitivity,evaluated through various detection methods and the quantum Cramér-Rao bound.This work holds potential applications in quantum metrology.
基金supported by the Fundamental Research Funds for the Central Universities (CDJXS 11 10 00 19)Mu Chunlai is supported by NSF of China(11071266)
文摘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.
基金supported by the National Natural Science Foundation of China(61471372)
文摘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.
基金supported by the National Natural Science Foundation of China(11301546).supported by the National Natural Science Foundation of China(11271147,11471136)
文摘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.
基金Acknowledgements This work was supported by National 13asie Research Program of China （2009CB320401）, National Natural Science Foundation of China （60972075, 61072055）, Key Scientific and Technologi- cal Project of China 2010ZX03003-003-01, and Fundamental Research Funds for the Central Universities （2009RC0116）.
文摘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.
文摘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.
文摘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.
基金Supported by the National Natural Science Foundation of China under Grant No. 11075015the Fundamental Research Funds for the Central Universities
文摘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.
基金Supported by the National Natural Science Foundation of China (61170324 and 61100105)
文摘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.
基金supported by a Research Grant of Andong National University NRF-2015R1A5A1009350 and NRF-2016R1D1A1B03930422。
文摘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.
