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Floquet spectrum and universal dynamics of a periodically driven two-atom system
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作者 谢文柱 周正强 +2 位作者 李轩 崔思淼 孙明远 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期436-443,共8页
We investigate the Floquet spectrum and excitation properties of a two-ultracold-atom system with periodically driven interaction in a three-dimensional harmonic trap.The interaction between the atoms is changed by va... We investigate the Floquet spectrum and excitation properties of a two-ultracold-atom system with periodically driven interaction in a three-dimensional harmonic trap.The interaction between the atoms is changed by varying the s-wave scattering length in two ways,the cosine and the square-wave modulations.It is found that as the driving frequency increases,the Floquet spectrum exhibits two main features for both modulations,the accumulating and the spreading of the quasienergy levels,which further lead to different dynamical behaviors.The accumulation is associated with collective excitations and the persistent growth of the energy,while the spread indicates that the energy is bounded at all times.The initial scattering length,the driving frequency and amplitude can all significantly change the Floquet spectrum as well as the dynamics.However,the corresponding relation between them is valid universally.Finally,we propose a mechanism for selectively exciting the system to one specific state by using the avoided crossing of two quasienergy levels,which could guide preparation of a desired state in experiments. 展开更多
关键词 Floquet spectrum universal dynamics two-atom system avoided crossing
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Teleportation of two-atom entangled state in resonant cavity quantum electrodynamics 被引量:9
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作者 杨贞标 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第2期329-334,共6页
An alternative scheme is presented for teleportation of a two-atom entangled state in cavity quantum electrodynamics (QED). It is based on the resonant atom-cavity field interaction. In the scheme, only one cavity i... An alternative scheme is presented for teleportation of a two-atom entangled state in cavity quantum electrodynamics (QED). It is based on the resonant atom-cavity field interaction. In the scheme, only one cavity is involved, and the number of the atoms needed to be detected is decreased compared with the previous scheme. Since the resonant atom-cavity field interaction greatly reduces the interaction time, the decoherence effect can be effectively suppressed during the teleportation process. The experimental feasibility of the scheme is discussed. The scheme can easily be generalized to the teleportation of N-atom Greeninger-Horne-Zeilinger (GHZ) entangled states. The number of atoms needed to be detected does not increase as the number of the atoms in the GHZ state increases. 展开更多
关键词 TELEPORTATION two-atom entangled state resonant cavity QED
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Probabilistic remote preparation of a two-atom entangled state 被引量:4
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作者 张英俏 金星日 张寿 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第9期1732-1735,共4页
A scheme for remotely preparing a two-atom entangled state via entanglement swapping in cavity quantum electronic dynamics (QED) with the help of separate measurements is proposed. And the effect of cavity decay is ... A scheme for remotely preparing a two-atom entangled state via entanglement swapping in cavity quantum electronic dynamics (QED) with the help of separate measurements is proposed. And the effect of cavity decay is eliminated in our scheme. 展开更多
关键词 remote state preparation entanglement swapping cavity QED two-atom entangled state
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Teleportation of a two-atom entangled state using a single EPR pair in cavity QED 被引量:2
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作者 计新 李克 张寿 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第3期478-481,共4页
We propose a scheme for teleporting a two-atom entangled state in cavity quantum electrodynamics (QED), In the scheme, we choose a single Einstein Podolsky Rosen (EPR) pair as the quantmn channel which is shared b... We propose a scheme for teleporting a two-atom entangled state in cavity quantum electrodynamics (QED), In the scheme, we choose a single Einstein Podolsky Rosen (EPR) pair as the quantmn channel which is shared by the sender and the receiver. By using the atom cavity-field interaction and introducing an additional atom, we can teleport the two-atom entangled state successfully with a probability of 1.0. Moreover, we show that the scheme is insensitive to cavity decay and thermal field. 展开更多
关键词 quantum teleportation two-atom entangled state cavity QED
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Scheme for realizing assisted cloning of an unknown two-atom entangled state via cavity QED 被引量:2
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作者 詹佑邦 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期411-414,共4页
This paper proposes a scheme where one can realize quantum cloning of an unknown two-atom entangled state with assistance of a state preparer in cavity QED. The first stage of the scheme requires usual teleportation. ... This paper proposes a scheme where one can realize quantum cloning of an unknown two-atom entangled state with assistance of a state preparer in cavity QED. The first stage of the scheme requires usual teleportation. In the second stage of the scheme, with the assistance of the preparer, the perfect copies of an unknown atomic entangled state can be produced. 展开更多
关键词 quantum cloning two-atom entangled state cavity QED
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Probabilistic Teleportation of an Arbitrary Two-Atom State in Cavity QED 被引量:2
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作者 LiU Jin-Ming 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3期446-450,共5页
We propose a scheme for the teleportation of an arbitrary two-atom state by using two pairs of two-atom nonmaximally entangled states as the quantum channel in cavity QED. It is Shown that no matter whether the arbitr... We propose a scheme for the teleportation of an arbitrary two-atom state by using two pairs of two-atom nonmaximally entangled states as the quantum channel in cavity QED. It is Shown that no matter whether the arbitrary two-atom pure state to be teleported is entangled or not, our teleportation scheme can always be probabilistically realized. The success prohability of teleportation is determined by the smaller coemcients of the two initially entangled atom pairs. 展开更多
关键词 quantum teleportation arbitrary two-atom state cavity QED
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Effects of spatial interference on intensity-intensity correlations in collective two-atom emission
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作者 谭华堂 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第1期311-317,共7页
In this paper, we investigate the effects of the spatial variation of driving-laser phase in a collective two-atom system on the intensity intensity correlations of the resonant fluorescence. It is shown that the inte... In this paper, we investigate the effects of the spatial variation of driving-laser phase in a collective two-atom system on the intensity intensity correlations of the resonant fluorescence. It is shown that the intensity-intensity correlations exhibit quite different characteristics for the different values of the spatial phase of the laser at the position of the two atoms in both cases of the weak and strong driving lasers. Our results suggest that the intensity intensity correlations can serve as a probe of the spatial interference effect arising from the spatial variation of the laser phase. 展开更多
关键词 spatial interference intensity-intensity correlations collective two-atomic system
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A Position-Dependent Two-Atom Entanglement in Real-Time Cavity QED System
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作者 GUO Yan-Qing CAO Hai-Jing SONG He-Shan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第1期59-62,共4页
We study a special two-atom entanglement case in assumed cavity QED experiment in which only one atom effectively exchanges a single photon with a cavity mode. We compute two-atom entanglement under position-dependent... We study a special two-atom entanglement case in assumed cavity QED experiment in which only one atom effectively exchanges a single photon with a cavity mode. We compute two-atom entanglement under position-dependent atomic resonant dipole-dipole interaction (RDDI) for large interatomic separation limit. We show that the RDDI, even t, hat which is much smaller than the maximal atomic Rabi frequency, can induce distinct diatom entanglement. The peak entanglement reaches a maximum when RDDI strength can compare with the Rabi frequency of an atom. 展开更多
关键词 two-atom entanglement cavity QED RDDI
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Alternative Scheme for Teleportation of Two-Atom Entangled State in Cavity QED
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作者 YANG Zhen-Biao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4X期623-626,共4页
We have proposed an alternative scheme for teleportation of two-atom entangled state in cavity QED. It is based on the degenerate Raman interaction of a single-mode cavity field with a A-type three-level atom. The pro... We have proposed an alternative scheme for teleportation of two-atom entangled state in cavity QED. It is based on the degenerate Raman interaction of a single-mode cavity field with a A-type three-level atom. The prominent feature of the scheme is that only one cavity is required, which is prior to the previous one. Moreover, the atoms need to be detected are reduced compared with the previous scheme. The experimental feasibility of the scheme is discussed. The scheme can easily be generalized for teleportation of N-atom GHZ entangled states. The number of the atoms needed to be detected does not increase as the number of the atoms in GHZ state increases. 展开更多
关键词 TELEPORTATION two-atom entangled state cavity QED
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The two-atom Jaynes-Cummings model's dynamic properties
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作者 QUJun GAOXiao-ming +3 位作者 LIANGJun PEIShi-xing HUANGWei ZHANGWei-jun 《原子与分子物理学报》 CAS CSCD 北大核心 2003年第2期202-206,210,共6页
The model of two two level atoms interact with a single mode cavity was investigated. The formulation of the time evolution operator for the two atom Jaynes Cummings model is pressented by the bare states approach. Be... The model of two two level atoms interact with a single mode cavity was investigated. The formulation of the time evolution operator for the two atom Jaynes Cummings model is pressented by the bare states approach. Besides, the time evolution of the two atom common population probabilities is studied, and some novel features are obtained. 展开更多
关键词 二能级原子模型 动力学 J-C模型 量子力学 相互作用
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Influence of selective atomic measurement on the entanglement properties of a two-atom outside cavity
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作者 卢道明 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第3期43-47,共5页
Considering three two-level atoms initially in the W or Greenberger-Horne-Zeilinger (GHZ) state, one of the three atoms is put into an initially coherent light cavity and made to resonantly interact with the cavity.... Considering three two-level atoms initially in the W or Greenberger-Horne-Zeilinger (GHZ) state, one of the three atoms is put into an initially coherent light cavity and made to resonantly interact with the cavity. The twoatom entanglement evolution outside the cavity is investigated. The influences of state-selective measurement of the atom inside the cavity and strength of the light field on the two-atom entanglement evolution outside the cavity are discussed. The results obtained from the numerical method show that the two-atom entanglement outside the cavity is strengthened through state-selective measurement of the atom inside the cavity. In addition, the strength of the light field also influences the two-atom entanglement properties. 展开更多
关键词 quantum optics two-level atom selective atomic measurement ENTANGLEMENT
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非线性相互作用引起的双模Dicke模型的新奇量子相变
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作者 赵秀琴 张文慧 王红梅 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第16期16-27,共12页
量子相变是量子光学和凝聚态物理领域的一个重要课题.本文在标准双模Dicke模型的基础上引入原子-光的非线性相互作用,研究其所引起的量子相变.利用自旋相干态变分法从理论上给出有两个参量的基态能量泛函.两模光场采用四种不同的比例关... 量子相变是量子光学和凝聚态物理领域的一个重要课题.本文在标准双模Dicke模型的基础上引入原子-光的非线性相互作用,研究其所引起的量子相变.利用自旋相干态变分法从理论上给出有两个参量的基态能量泛函.两模光场采用四种不同的比例关系进行研究,并且在实验参数下,通过可调的原子-光的非线性相互作用参量,给出了宏观多粒子量子态的丰富结构.本文主要呈现了在蓝失谐和红失谐下,双稳的正常相、共存的正常-超辐射相和原子数反转态等丰富的基态特性.原子-光的非线性相互作用在蓝失谐可以引起标准的双模Dicke模型的正常相到超辐射相的二级量子相变.在红失谐时引起新奇的基态特性,新奇的量子相变,即反转的超辐射相到反转的正常相的二级逆量子相变.原子-光的非线性相互作用和两模光场比例不同时,对量子相变的相边界和基态物理量的值有较大影响. 展开更多
关键词 双模Dicke模型 原子-光的非线性相互作用 量子相变 自旋相干态法
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Preparation of genuine Yeo-Chua entangled state and teleportation of two-atom state via cavity QED 被引量:3
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作者 ZHANG Wen LIU YiMin +1 位作者 ZUO XueQin ZHANG ZhanJun 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2010年第12期2232-2237,共6页
We first propose a scheme for preparing the genuine Yeo-Chua 4-qubit entangled state via cavity QED. Using the genuine Yeo-Chua atomic state, we further propose a cavity QED scheme for teleporting an arbitrary two-ato... We first propose a scheme for preparing the genuine Yeo-Chua 4-qubit entangled state via cavity QED. Using the genuine Yeo-Chua atomic state, we further propose a cavity QED scheme for teleporting an arbitrary two-atom state. In two schemes the large-detuning is chosen and the necessary time is designed to be much shorter than Rydberg-atom’s lifespan. Both schemes share the distinct advantage that cavity decay and atom decay can be neglected. As for the interaction manipulation, our preparation scheme is more feasible than a recent similar one. Compared with the Yeo and Chua’s scheme, our teleportation scheme has significantly reduced the measuring difficulty. 展开更多
关键词 cavity QED PREPARATION genuine Yeo-Chua atomic state teleportation arbitrary two-atom state
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Teleportation of an unknown two-atom state using simultaneous interaction of two two-level atoms with cavity field 被引量:2
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作者 向少华 宋克慧 《Chinese Optics Letters》 SCIE EI CAS CSCD 2003年第8期488-490,共3页
Proposal for the teleportation of two-atom state is presented. It is based on the simultaneous interaction of two two-level atoms with a single-mode cavity with a filed of n photons. In the proposed scheme, two pairs ... Proposal for the teleportation of two-atom state is presented. It is based on the simultaneous interaction of two two-level atoms with a single-mode cavity with a filed of n photons. In the proposed scheme, two pairs of EPR state are used as quantum channel to teleport an unknown two-atom state. The completed time is greatly reduced and cavity field is not required to be detected are shown to be the distinct features of the presented scheme. 展开更多
关键词 of on for be that into Teleportation of an unknown two-atom state using simultaneous interaction of two two-level atoms with cavity field with
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取向硅钢常化冷却段空气雾化喷嘴内流场数值模拟
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作者 刘向荣 刘婷 +5 位作者 郭小龙 骆新根 戴惠磊 郭悦 程朝阳 戴方钦 《科学技术与工程》 北大核心 2024年第28期12095-12104,共10页
为改善取向硅钢常化过程带钢的冷却效果,对空气雾化喷嘴内气液两相流动过程进行三维数值模拟研究,分析空气压力和水流量对喷嘴内流场速度和液相体积分数的影响。数值计算值与实验测试值吻合良好且最大误差小于10%。结果表明:当水流量一... 为改善取向硅钢常化过程带钢的冷却效果,对空气雾化喷嘴内气液两相流动过程进行三维数值模拟研究,分析空气压力和水流量对喷嘴内流场速度和液相体积分数的影响。数值计算值与实验测试值吻合良好且最大误差小于10%。结果表明:当水流量一定时,随着空气压力的逐渐增大,喷嘴内速度增大、液相体积分数减小,喷嘴出口处速度分布均匀性变差,液相体积分数分布更均匀;当空气压力一定时,随着水流量的逐渐增大,喷嘴内速度逐渐减小、液相体积分数增大,喷嘴出口处速度分布更均匀,液相体积分数分布均匀性变差;喷嘴气水压力比为1.1时冷却均匀性较好,冷却均匀性最佳的工况为空气压力0.2 MPa、水流量180 L/h。 展开更多
关键词 取向硅钢 常化冷却 空气雾化喷嘴 两相流动 数值模拟
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耦合系数与腔衰减率对单原子腔场的二阶相关度及原子布居概率的影响
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作者 刘钰梵 马春兰 曲秀荣 《哈尔滨师范大学自然科学学报》 CAS 2024年第3期29-33,共5页
采用单原子J-C模型研究单个二能级原子与单模量子光场的相互作用.主要研究强耦合与弱耦合情况下,二阶相关度及原子布居概率随标度时间的变化.同时,分别探讨了弱耦合下原子与腔场的耦合系数及强耦合下腔场衰减率对二阶相关度及原子布居... 采用单原子J-C模型研究单个二能级原子与单模量子光场的相互作用.主要研究强耦合与弱耦合情况下,二阶相关度及原子布居概率随标度时间的变化.同时,分别探讨了弱耦合下原子与腔场的耦合系数及强耦合下腔场衰减率对二阶相关度及原子布居概率的影响.发现弱耦合下腔场与原子的耦合系数对光场反聚束效应有削弱作用,强耦合下腔场衰减率值对光场反聚束效应有增强作用.另外弱耦合下耦合系数与强耦合下腔衰减率对原子处于上能级概率均有抑制作用. 展开更多
关键词 二能级原子 布居概率 二阶关联度
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基于二维磁光阱的增强型^(199)Hg冷原子团制备 被引量:1
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作者 余泽鑫 刘琪鑫 +1 位作者 孙剑芳 徐震 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第1期140-148,共9页
在精密测量领域中,高效地制备冷原子团具有重要的意义.在光晶格钟里,缩短冷原子团的制备时间可以降低Dick噪声,从而提高光晶格钟的稳定性.本文采用二维磁光阱加推送光的构型提高了三维磁光阱在超高真空环境中的装载率,并通过压缩磁光阱... 在精密测量领域中,高效地制备冷原子团具有重要的意义.在光晶格钟里,缩短冷原子团的制备时间可以降低Dick噪声,从而提高光晶格钟的稳定性.本文采用二维磁光阱加推送光的构型提高了三维磁光阱在超高真空环境中的装载率,并通过压缩磁光阱技术降低了原子团温度,实现了用于^(199)Hg光晶格钟的增强型冷原子团制备.实验上通过优化三维和二维磁光阱的失谐量和磁场梯度以及推送光的失谐量和功率等参数,将三维磁光阱的^(199)Hg冷原子装载率增强了51倍,提升至3.1×10^(5)s^(–1),然后使用压缩磁光阱技术将^(199)Hg冷原子团的温度降低至45μK,低于多普勒冷却理论温度.这种基于二维磁光阱的增强型冷原子团制备可在超真空环境下实现对三维磁光阱装载率的高增益,有效地缩短了冷原子团的制备时间,同时也降低了原子团的温度,有利于提高光晶格的转移效率,为其他冷原子实验中冷汞原子团制备提供了有效方案. 展开更多
关键词 汞原子 光晶格钟 激光冷却 二维磁光阱
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基于全球导航卫星系统应用的光频原子钟发展现状与可用性分析
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作者 宋冰冰 陈江 +1 位作者 廉吉庆 刘志栋 《真空与低温》 2024年第6期664-679,共16页
随着光频原子钟技术迅速发展,光频原子钟不确定度已超越微波原子钟性能4~5个数量级,达到了10^(−19)数量级,在可靠性和小型化方面也不断提升,使得未来全球导航卫星系统(Global Navigation Satellite System,GNSS)搭载光频原子钟成为可能... 随着光频原子钟技术迅速发展,光频原子钟不确定度已超越微波原子钟性能4~5个数量级,达到了10^(−19)数量级,在可靠性和小型化方面也不断提升,使得未来全球导航卫星系统(Global Navigation Satellite System,GNSS)搭载光频原子钟成为可能。介绍了几种GNSS光频原子钟的工作原理及国内外的研究进展,从稳定度、集成度及影响稳定度的因素等方面总结了几种光频原子钟的性能,并将四种光学时钟(离子光钟、光晶格钟、双光子跃迁光频原子钟、基于碘调制转移谱光频原子钟)与目前GNSS上搭载的四大导航系统进行比较,讨论了光频原子钟的应用潜力,并提出了各光频原子钟的发展建议。针对提升离子光钟和光晶格钟可靠性的需求,提出了通过提高激光器和超稳腔的稳定性、降低核心器件环境敏感性的建议。针对提升原子束光频原子钟稳定性的需求,提出了提高原子束利用率、进一步迭代实验等方案。针对提升双光子跃迁光频原子钟和调制转移谱光频原子钟的长期稳定性的需求,提出了结合真空技术及人工智能降低频率漂移率的解决方案。 展开更多
关键词 全球导航卫星系统 光频原子钟 原子束 双光子跃迁 调制转移谱
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阵元失效下稀疏阵列的二维DOA估计算法
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作者 司伟建 马万禹 +2 位作者 姚璐 曲明超 梁义鲁 《航空兵器》 CSCD 北大核心 2024年第2期114-122,共9页
本文针对二维稀疏阵列在阵元失效条件下,因数据缺失导致虚拟阵列连续性被破坏及自由度下降的问题,提出了一种二维DOA估计算法。首先基于二维差分共阵构建虚拟阵列,然后利用解耦原子范数最小化理论,以矩阵填充的形式恢复协方差矩阵数据,... 本文针对二维稀疏阵列在阵元失效条件下,因数据缺失导致虚拟阵列连续性被破坏及自由度下降的问题,提出了一种二维DOA估计算法。首先基于二维差分共阵构建虚拟阵列,然后利用解耦原子范数最小化理论,以矩阵填充的形式恢复协方差矩阵数据,实现对虚拟阵列中丢失虚拟阵元的内插,最后采用SS-MUSIC算法进行多信源的二维DOA估计。所提方法弥补了物理阵元失效所造成的影响,恢复了原始虚拟阵列的完整孔径特性,保持了虚拟阵列的自由度,从而确保了较高精度的二维DOA估计性能。仿真实验结果表明,在相同阵元数量及阵元失效情况下,本文提出的算法相比已有方法能有效地估计更多信源,并在小快拍数和低信噪比条件下表现出更高的稳健性,最大限度地保留并利用了稀疏阵列在二维DOA估计中的自由度优势。 展开更多
关键词 二维DOA估计 稀疏阵列 差分共阵 阵元失效 解耦原子范数最小化 矩阵填充
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基于水气两相流的海拔高程对某电站溢洪道泄洪雾化的影响分析
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作者 张艳玲 童富果 刘刚 《水电能源科学》 北大核心 2024年第1期120-124,共5页
海拔高程增加所引起的气象条件的改变会对泄洪水舌的运动产生影响,进而影响泄洪雾化风场及雨场的时空分布。为此,基于水气两相流理论,考虑不同海拔高度的环境压强、温度、粘滞性及空气密度等参数的变化,采用数值模拟的方法研究了海拔高... 海拔高程增加所引起的气象条件的改变会对泄洪水舌的运动产生影响,进而影响泄洪雾化风场及雨场的时空分布。为此,基于水气两相流理论,考虑不同海拔高度的环境压强、温度、粘滞性及空气密度等参数的变化,采用数值模拟的方法研究了海拔高程对泄洪雾化的影响。结果表明,相同泄洪条件下,泄洪稳定后的压强值随海拔升高无明显增加趋势,然而海拔越高,水舌空中运动所受空气阻力越小,相同条件下落水点压强增幅越大;温度降低带来的水的粘滞性增加对水雾运动影响较小,海拔高程越高,雾化风速到达最大值的时间越早,所能达到的最大值也越大;泄洪稳定时近地表雾化降雨强度随海拔高程的增加而增大,与海拔高程呈近似线性关系,此外强降雨范围随海拔的升高而逐渐扩大。 展开更多
关键词 泄洪雾化 水气两相流 数值模拟 高海拔
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