Array configuration of multiple-input multiple-output (MIMO) radar with non-uniform linear array (NLA) is proposed. Unlike a standard phased-array radar where NLA is used to generate thinner beam patterns, in MIMO...Array configuration of multiple-input multiple-output (MIMO) radar with non-uniform linear array (NLA) is proposed. Unlike a standard phased-array radar where NLA is used to generate thinner beam patterns, in MIMO radar the property of NLA is exploited to get more distinct virtual array elements so as to improve pa- rameter identifiability, which means the maximum number of targets that can be uniquely identified by the radar. A class of NLA called minimum redundancy linear array (MRLA) is employed and a new method to construct large MRLAs is descrihed. The numerical results verify that compared to uniform linear array (ULA) MIMO radars, NLA MIMO radars can retain the same parameter identifiability with fewer physical antennas and achieve larger aperture length and lower Cramer-Rao bound with the same number of the physical antennas.展开更多
In this paper, asymmetric Gaussian weighting functions are introduced for the identification of linear parameter varying systems by utilizing an input-output multi-model structure. It is not required to select operati...In this paper, asymmetric Gaussian weighting functions are introduced for the identification of linear parameter varying systems by utilizing an input-output multi-model structure. It is not required to select operating points with uniform spacing and more flexibility is achieved. To verify the effectiveness of the proposed approach, several weighting functions, including linear, Gaussian and asymmetric Gaussian weighting functions, are evaluated and compared. It is demonstrated through simulations with a continuous stirred tank reactor model that the oroposed aonroach nrovides more satisfactory aonroximation.展开更多
Taking the decoherence effect into account, the entanglement evolution of a two-qubit anisotropic Heisenberg XYZ chain in the presence of inhomogeneous magnetic field is investigated. The time evolution of concurrence...Taking the decoherence effect into account, the entanglement evolution of a two-qubit anisotropic Heisenberg XYZ chain in the presence of inhomogeneous magnetic field is investigated. The time evolution of concurrence is studied for the initial state cos θ|01) + sin θ|10) at zero temperature. The influences of inhomogeneous magnetic field, anisotropic parameter and decoherence on entanglement dynamic are addressed in detail, and a concurrence formula of the steady state is found. It is shown that the entanglement sudden death (ESD) and entanglement sudden birth (ESB) appear with the decoherence effect, and the stable concurrence depends on the uniform magnetic field B, anisotropic parameter △ and environment coupling strength γ, which is independent of different initial states and nonuniform magnetic field b.展开更多
Hydraulic performance of an inlet plenum in a printed-circuit heat exchanger has been analyzed using three-dimensional Reynolds-Averaged Navier-Stokes equations. The numerical model of the inlet plenum was constructed...Hydraulic performance of an inlet plenum in a printed-circuit heat exchanger has been analyzed using three-dimensional Reynolds-Averaged Navier-Stokes equations. The numerical model of the inlet plenum was constructed through grid dependency test, calculation domain tests, and turbulence model and numerical scheme selections. Shear stress transport turbulence model was used for analysis of turbulence. Non-uniformity of the flow in zigzag flow channels was evaluated for the reference case. Parametric studies have been performed with the angle of the inlet plenum wall, radius of curvature of the inlet plenum wall, and width of the inlet pipes. The effects of these parameters on the flow uniformity and friction performance were evaluated.展开更多
This paper discusses the influence of the anisotropy parameters on elliptical-polarization of the inhomogenously refracted P-wave induced at VTI-media interface.For this refracted P-wave,we have derived,the equations ...This paper discusses the influence of the anisotropy parameters on elliptical-polarization of the inhomogenously refracted P-wave induced at VTI-media interface.For this refracted P-wave,we have derived,the equations of the elliptical-polarization trajectory.Following the elliptical-polarization trajectory,we calculated the effects of the rock anisotropic-parameters on the polarization state,with a Poincare-sphere-like representation,for several varying media parameters.It is noted that the size,shape and initial phase angle of the elliptical-polarization trajectory are all depending the anisotropy media,as well as on the incident-angle.We expect that the findings from this paper would be applied to practical applications of seismic exploration.展开更多
基金Supported by the Aeronautic Science Foundation of China(2008ZC52026)the Innovation Foundation of Nanjing University of Aeronautics and Astronautics~~
文摘Array configuration of multiple-input multiple-output (MIMO) radar with non-uniform linear array (NLA) is proposed. Unlike a standard phased-array radar where NLA is used to generate thinner beam patterns, in MIMO radar the property of NLA is exploited to get more distinct virtual array elements so as to improve pa- rameter identifiability, which means the maximum number of targets that can be uniquely identified by the radar. A class of NLA called minimum redundancy linear array (MRLA) is employed and a new method to construct large MRLAs is descrihed. The numerical results verify that compared to uniform linear array (ULA) MIMO radars, NLA MIMO radars can retain the same parameter identifiability with fewer physical antennas and achieve larger aperture length and lower Cramer-Rao bound with the same number of the physical antennas.
基金Supported by the National Natural Science Foundation of China(21076179,61104008)National Basic Research Program of China(2012CB720500)
文摘In this paper, asymmetric Gaussian weighting functions are introduced for the identification of linear parameter varying systems by utilizing an input-output multi-model structure. It is not required to select operating points with uniform spacing and more flexibility is achieved. To verify the effectiveness of the proposed approach, several weighting functions, including linear, Gaussian and asymmetric Gaussian weighting functions, are evaluated and compared. It is demonstrated through simulations with a continuous stirred tank reactor model that the oroposed aonroach nrovides more satisfactory aonroximation.
基金Supported by National Natural Science Foundation of China under Grant No.10904033Natural Science Foundation of Hubei Province under Grant No.2009CDA145+1 种基金Educational Commission of Hubei Province under Grant No.D20092204Natural Science Foundation of Hubei Normal University under Grant No.2007D21
文摘Taking the decoherence effect into account, the entanglement evolution of a two-qubit anisotropic Heisenberg XYZ chain in the presence of inhomogeneous magnetic field is investigated. The time evolution of concurrence is studied for the initial state cos θ|01) + sin θ|10) at zero temperature. The influences of inhomogeneous magnetic field, anisotropic parameter and decoherence on entanglement dynamic are addressed in detail, and a concurrence formula of the steady state is found. It is shown that the entanglement sudden death (ESD) and entanglement sudden birth (ESB) appear with the decoherence effect, and the stable concurrence depends on the uniform magnetic field B, anisotropic parameter △ and environment coupling strength γ, which is independent of different initial states and nonuniform magnetic field b.
基金supported by the National Research Foundation of Korea (NRF), (Grant No. 2009-0083510)funded by the Korean government (MSIP) through the Multi-phenomena CFD Engineering Research Center
文摘Hydraulic performance of an inlet plenum in a printed-circuit heat exchanger has been analyzed using three-dimensional Reynolds-Averaged Navier-Stokes equations. The numerical model of the inlet plenum was constructed through grid dependency test, calculation domain tests, and turbulence model and numerical scheme selections. Shear stress transport turbulence model was used for analysis of turbulence. Non-uniformity of the flow in zigzag flow channels was evaluated for the reference case. Parametric studies have been performed with the angle of the inlet plenum wall, radius of curvature of the inlet plenum wall, and width of the inlet pipes. The effects of these parameters on the flow uniformity and friction performance were evaluated.
基金supported by Xi'an University of Posts and Telecommunications,and the Physical Sciences Division at The University of Chicago
文摘This paper discusses the influence of the anisotropy parameters on elliptical-polarization of the inhomogenously refracted P-wave induced at VTI-media interface.For this refracted P-wave,we have derived,the equations of the elliptical-polarization trajectory.Following the elliptical-polarization trajectory,we calculated the effects of the rock anisotropic-parameters on the polarization state,with a Poincare-sphere-like representation,for several varying media parameters.It is noted that the size,shape and initial phase angle of the elliptical-polarization trajectory are all depending the anisotropy media,as well as on the incident-angle.We expect that the findings from this paper would be applied to practical applications of seismic exploration.