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双模索引辅助广义空间调制系统设计 被引量:1
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作者 王相相 冯兴乐 韩佳倩 《数据采集与处理》 CSCD 北大核心 2021年第6期1157-1166,共10页
广义空间调制(Generalized spatial modulation,GSM)技术通过选择部分发射天线来传输信息,该系统由于部分天线保持静默而造成系统传输速率低。为了提高系统的传输速率,将GSM系统的所有发射天线均激活,但该系统在接收端依旧很难恢复出发... 广义空间调制(Generalized spatial modulation,GSM)技术通过选择部分发射天线来传输信息,该系统由于部分天线保持静默而造成系统传输速率低。为了提高系统的传输速率,将GSM系统的所有发射天线均激活,但该系统在接收端依旧很难恢复出发射信号。为了达到传输速率与系统性能这两方面的平衡,本文提出双模广义空间调制系统,该系统将每时隙发送的信息比特分为索引比特和星座调制比特,利用索引比特将所有发射天线分为两组,将两种可分辨的星座调制符号分别放在两组天线上同时进行发送,在接收端采用最大似然算法(Maximum likelihood,ML)进行检测解调得到发送符号。通过分析与仿真表明,在误比特率为10-3时,双模广义空间调制系统与发射总功率且传输速率均相同的GSM系统和多输入多输出(Multiple input multiple output,MIMO)系统相比,前者采用低阶调制方式来最大化星座点间的欧氏距离,将获得约4 dB的增益,后者在接收端可通过功率索引来提升检测算法性能,将获得约2 dB的增益。 展开更多
关键词 双模广义空间调制 索引调制 星座模式 功率分配 传输速率
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双模相位算符及其本征态 被引量:1
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作者 李洪才 《量子光学学报》 CSCD 1997年第1期19-27,共9页
在双模空间,给出不同模式下厄米的cosiue和Sine算符。由于它们相互对易,就可构造出它们的共同本征态。并且讨论了这些相位算符和本征态矢的性质。最后还研究了在P-B相位表示下这些算符的期望值。
关键词 双模空间 相位算符 本征态矢 量子光学
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超对称谐振子的双模相位算符及其本征态
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作者 黄万霞 汪茂胜 王勤谋 《量子电子学报》 CAS CSCD 北大核心 2004年第6期802-806,共5页
在超对称谐振子的双摸相位空间里构造了二类独立的相位算符并相应地求出了其本征态。
关键词 量子光学 超对称谐振子 超对称湮没算符 双模空间 相位算符
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关于双模相位算符的讨论 被引量:1
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作者 李洪才 《福建师范大学学报(自然科学版)》 CAS CSCD 1997年第3期23-27,共5页
在双模空间,给出不同模式下厄米的cosine和sine算符.研究它们的对易性质,构造出它们共同本征态.并且讨论了这些相位算符和本征态矢的性质.最后还研究了在P-B相位表示下这些算符的期望值及几率特征.
关键词 双模空间 相位算符 厄米算符 本征态矢 量子力学
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双模Fock空间中若干新的算符恒等式
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作者 井思聪 范洪义 《科学通报》 EI CAS CSCD 北大核心 1993年第7期606-609,共4页
双模Fock空间是量子力学中研究许多物理系统与状态的粒子数表象的希尔伯特空间。本文将给出此空间中若干新的算符恒等式,这些关系对于证明双模Fock空间中的一类完备性关系十分有用。设a(a^+),b(b^+)代表双模谐振子消灭(产生)算符,满足... 双模Fock空间是量子力学中研究许多物理系统与状态的粒子数表象的希尔伯特空间。本文将给出此空间中若干新的算符恒等式,这些关系对于证明双模Fock空间中的一类完备性关系十分有用。设a(a^+),b(b^+)代表双模谐振子消灭(产生)算符,满足如下对易关系: [a,a^+]=[b,b^+]=1,[a,b]=[a,b^+]=0 (1)相应的粒子数算符是N_a=a^+a与N_b=b^+b。 展开更多
关键词 算符恒等式 双模Fock空间 量子力学
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Single-trial EEG-based emotion recognition using temporally regularized common spatial pattern
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作者 成敏敏 陆祖宏 王海贤 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期55-60,共6页
This study addresses the problem of classifying emotional words based on recorded electroencephalogram (EEG) signals by the single-trial EEG classification technique. Emotional two-character Chinese words are used a... This study addresses the problem of classifying emotional words based on recorded electroencephalogram (EEG) signals by the single-trial EEG classification technique. Emotional two-character Chinese words are used as experimental materials. Positive words versus neutral words and negative words versus neutral words are classified, respectively, using the induced EEG signals. The method of temporally regularized common spatial patterns (TRCSP) is chosen to extract features from the EEG trials, and then single-trial EEG classification is achieved by linear discriminant analysis. Classification accuracies are between 55% and 65%. The statistical significance of the classification accuracies is confirmed by permutation tests, which shows the successful identification of emotional words and neutral ones, and also the ability to identify emotional words. In addition, 10 out of 15 subjects obtain significant classification accuracy for negative words versus neutral words while only 4 are significant for positive words versus neutral words, which demonstrate that negative emotions are more easily identified. 展开更多
关键词 emotion recognition temporal regularization common spatial patterns(CSP) two-character Chinese words permutation test
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New Two-Mode Coherent-Intermediate-Entangled State and Its Squeezing Operator
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作者 XU Shi-Min XU Xing-Lei LI Hong-Qi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第11期808-812,共5页
The coherent-intermediate-entangled state |α, x)λ,v is proposed in the two-mode Fock Space, which exhibits both the properties of the coherent and entangled states. The |α, x)λ,v makes up a new quantum mechan... The coherent-intermediate-entangled state |α, x)λ,v is proposed in the two-mode Fock Space, which exhibits both the properties of the coherent and entangled states. The |α, x)λ,v makes up a new quantum mechanical representation, and the completeness relation of |α, x)λ,v is proved by virtue of the technique of integral within an ordered product of operators. The corresponding squeezing operators are derived. Furthermore, Generalized P-representation is constructed in the coherent-intermediate-entangled state |α, x)λ,v and the Schmidt decomposition of |α, x)λ,v is investigated. 展开更多
关键词 bipartite coherent-intermediate-entangled state IWOP technique classical transformation
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On a Quasilinear Hyperbolic System Relative to an Atmospheric Model on the Transition of Water Defined on the Whole Space
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作者 Steave C. Selvaduray 《Journal of Mathematics and System Science》 2014年第9期637-655,共19页
In this paper we study a quasi-linear hyperbolic system, with some integral operators, arising from an atmospheric model on the transition of water. By using the method of characteristics and a fixed point argument, w... In this paper we study a quasi-linear hyperbolic system, with some integral operators, arising from an atmospheric model on the transition of water. By using the method of characteristics and a fixed point argument, we prove a theorem of existence, uniqueness and continuous dependence on data, in Lipschitz class, of the solution to this problem. 展开更多
关键词 Cauchy problem method of characteristics functional quasilinear system phase transition
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Dynamic analysis on methanation reactor using a double-input–multi-output linearized model
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作者 李星星 李佳庚 +1 位作者 杨伯伦 张勇 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第2期389-397,共9页
A double-input–multi-output linearized system is developed using the state-space method for dynamic analysis of methanation process of coke oven gas.The stability of reactor alone and reactor with feed-effluent heat ... A double-input–multi-output linearized system is developed using the state-space method for dynamic analysis of methanation process of coke oven gas.The stability of reactor alone and reactor with feed-effluent heat exchanger is compared through the dominant poles of the system transfer functions.With single or double disturbance of temperature and CO concentration at the reactor inlet,typical dynamic behavior in the reactor,including fast concentration response,slow temperature response and inverse response,is revealed for further understanding of the counteraction and synergy effects caused by simultaneous variation of concentration and temperature.Analysis results show that the stability of the reactor loop is more sensitive than that of reactor alone due to the positive heat feedback.Remarkably,with the decrease of heat exchange efficiency,the reactor system may display limit cycle behavior for a pair of complex conjugate poles across the imaginary axis. 展开更多
关键词 Coke oven gas methanation Synthetic natural gas Double-input–multi-output linearized system Dynamic analysis Limit cycle behavior
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双模相位问题 被引量:1
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作者 李洪才 《物理学报》 SCIE EI CAS CSCD 北大核心 1997年第7期1259-1266,共8页
在双模空间,给出两种模式下厄密的cosine和sine算符.由于它们互相对易,就可构造出它们的共同本征态.讨论了这些相位算符和本征态矢的性质.
关键词 双模空间 本征态矢 相位算符
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THE REALIZATION OF MULTIPLIER HILBERT BIMODULE ON BIDUAL SPACE AND TIETZE EXTENSION THEOREM 被引量:1
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作者 FANG XIAOCHUN(Department of Mathematics, Tongji University, Shanghai 200092, China) E-mail: xfang@online.sh.cn 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2000年第3期375-380,共6页
The multiplier bimodule of Hilbert bimodule is introduced in a way similar to [1], and its realization on a quotient of bidual space and Tietze extension theorem are obtained similar to that in C-algebra case. As a re... The multiplier bimodule of Hilbert bimodule is introduced in a way similar to [1], and its realization on a quotient of bidual space and Tietze extension theorem are obtained similar to that in C-algebra case. As a result, the multiplier bimodule here is also a Hilbert bimodule. 展开更多
关键词 Realization on bidual space Multiplier Hilbert bimodule Tietze extension theorem
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Entanglement transfer from two-mode squeezed vacuum light to spatially separated mechanical oscillators via dissipative optomechanical coupling 被引量:3
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作者 YAN Yan GU WenJu LI GaoXiang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2015年第5期52-59,共8页
In this paper, we propose a scheme to generate an entangled state between two spatially separated movable mirrors by injecting the two-mode squeezed optical reservoir to the dissipative optomechanics, in which the mov... In this paper, we propose a scheme to generate an entangled state between two spatially separated movable mirrors by injecting the two-mode squeezed optical reservoir to the dissipative optomechanics, in which the movable mirrors can modulate the linewidth of the cavity modes. When the coupling between the mirrors and the corresponding cavity modes is weak, the two driven cavity fields can respectively behave as the squeezed-vacuum reservoir for the two movable mirrors by utilizing the effect of completely destructive interference of quantum noise. Thus the mechanical modes are prepared in a two-mode squeezed vacuum state. Moreover,when the coupling between the two mirrors and the cavities modes is strong, the entanglement between the two movable mirrors decreases because photonic excitation can preclude the completely destructive interference of quantum noise, but the movable mirrors are still entangled. 展开更多
关键词 EPR mechanical entanglement double dissipative optomechanics efficient transfer of quantum correlations
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On the algorithmic construction of classifying spaces and the isomorphism problem for biautomatic groups
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作者 BRIDSON Martin R. REEVES Lawrence 《Science China Mathematics》 SCIE 2011年第8期1533-1545,共13页
We show that the isomorphism problem is solvable in the class of central extensions of word-hyperbolic groups,and that the isomorphism problem for biautomatic groups reduces to that for biautomatic groups with finite ... We show that the isomorphism problem is solvable in the class of central extensions of word-hyperbolic groups,and that the isomorphism problem for biautomatic groups reduces to that for biautomatic groups with finite centre.We describe an algorithm that,given an arbitrary finite presentation of an automatic group Γ,will construct explicit finite models for the skeleta of K(Γ,1) and hence compute the integral homology and cohomology of Γ. 展开更多
关键词 geometric group theory automatic groups isomorphism problem
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