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Nonstandard Unitary Transformations of Quantum States
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作者 Gombojav O. Ariunbold 《Journal of Applied Mathematics and Physics》 2023年第9期2568-2575,共8页
In quantum optics, unitary transformations of arbitrary states are evaluated by using the Taylor series expansion. However, this traditional approach can become cumbersome for the transformations involving non-commuti... In quantum optics, unitary transformations of arbitrary states are evaluated by using the Taylor series expansion. However, this traditional approach can become cumbersome for the transformations involving non-commuting operators. Addressing this issue, a nonstandard unitary transformation technique is highlighted here with new perspective. In a spirit of “quantum” series expansions, the transition probabilities between initial and final states, such as displaced, squeezed and other nonlinearly transformed coherent states are obtained both numerically and analytically. This paper concludes that, although this technique is novel, its implementations for more extended systems are needed. 展开更多
关键词 Taylor Series Unitary transformation Temporal Evolution Displaced state Coherent state Squeezed state Two-Mode Squeezed state Holstein-Primakoff state
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STATE TRANSFORMATION PROCESSES FOR FREE-FLOATING THREE-LINK PLANAR ROBOTS 被引量:1
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作者 XuMingtao XuYangsheng JamesK.Mills 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第2期166-169,共4页
The transformation process of an m-DOF free-floating robot from one staticstate to a different static state has m degrees of freedom. The proposed approach of thesetransformations utilizes a series of single-DOF trans... The transformation process of an m-DOF free-floating robot from one staticstate to a different static state has m degrees of freedom. The proposed approach of thesetransformations utilizes a series of single-DOF transformation processes as an alternative to them-DOF transformation process. Two static state transformation processes are studied in detail.First, a single-DOF transformation process is established using a newly defined concept, referred toas transformation planning, and the definite integral of conservation of angular momentum. Second,the governing equation of the single-DOF transformation process is established using the dynamicequations of motion of the robot. This allows the joint torques to be computed to effect the statetransformation. Finally, an extension of the single-DOF transformation process is proposed to extendthe application of this proposed transformation methodology to create a transformation net whichallows the reconfiguration of a robot from one state to many other possible states. 展开更多
关键词 Planar robot Static state Single-DOF transformation process n-elementtransformation net
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基于CNN-Transformer的锂离子电池健康状态估计 被引量:1
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作者 陈国麟 姚行艳 《重庆工商大学学报(自然科学版)》 2024年第2期66-73,共8页
目的健康状态是评估锂离子电池状态的关键参数,对锂离子电池的安全使用有着十分重要的意义,为了获得准确可靠的健康状态估计结果,建立基于卷积神经网络和Transformer的锂离子电池健康状态估计方法,利用不同模型的数据挖掘特性,将健康指... 目的健康状态是评估锂离子电池状态的关键参数,对锂离子电池的安全使用有着十分重要的意义,为了获得准确可靠的健康状态估计结果,建立基于卷积神经网络和Transformer的锂离子电池健康状态估计方法,利用不同模型的数据挖掘特性,将健康指标的深层信息和随循环周期增加的时序信息并行提取。方法从锂离子电池放电过程中的部分电压和温度曲线中提取3个与健康状态相关性较强的健康指标作为模型输入,利用卷积神经网络强大的特征提取能力挖掘健康指标的局部特征,利用Transformer的顺序处理能力挖掘健康指标的时序特征,将健康指标的局部特征和时序特征进行特征融合,通过卷积和全局平均池化层输出健康状态估计值。结果本研究使用MIT数据集进行实验验证,并与卷积神经网络和长短时记忆神经网络进行对比分析,所提出的方法的均方根误差和平均绝对误差是最低的,为0.11和0.08,最小相对误差为0.61%。结论所提出的CNN-Transformer健康状态估计采用不同模型挖掘健康指标不同的特征信息,能够充分利用锂离子电池放电数据,且具有良好的估计效果。 展开更多
关键词 锂离子电池 健康状态 卷积神经网络 transformER
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Two mutually conjugated tripartite entangled states and their fractional Fourier transformation kernel 被引量:1
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作者 吕翠红 范洪义 姜年权 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期43-50,共8页
We newly construct two mutually-conjugate tripartite entangled state representations, based on which we propose the formulation of three-mode entangled fractional Fourier transformation (EFFT) and derive the transfo... We newly construct two mutually-conjugate tripartite entangled state representations, based on which we propose the formulation of three-mode entangled fractional Fourier transformation (EFFT) and derive the transformation kernel. The EFFT's additivity property is proved and the eigenmode of EFFT is derived. As an application, we calculate the EFFT of the three-mode squeezed vacuum state. 展开更多
关键词 tripartite entangled state three-mode entangled fractional Fourier transformation the technique of integral within an ordered product of operators
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Inverse Transformation of Elliptical Relative State Transition Matrix 被引量:1
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作者 Jianfeng Yin Yinrui Rao Chao Han 《International Journal of Astronomy and Astrophysics》 2014年第3期419-428,共10页
A new set of relative orbit elements (ROEs) is used to derive a new elliptical formation flying model in previous work. In-plane and out-of-plane relative motions can be completely decoupled, which benefits elliptical... A new set of relative orbit elements (ROEs) is used to derive a new elliptical formation flying model in previous work. In-plane and out-of-plane relative motions can be completely decoupled, which benefits elliptical formation design. In order to study the elliptical control strategy and perturbation effects, it is necessary to derive the inverse transformation of the relative state transition matrix based on relative orbit elements. Poisson bracket theory is used to obtain the linear transformations between the two representations: the relative orbit elements and the geocentric orbital frame. In this paper, the details of these transformations are presented. 展开更多
关键词 RELATIVE ORBIT Elements ELLIPTICAL Formation FLYING RELATIVE state Transition Matrix Inverse transformation POISSON BRACKET
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Effects of high-pressure heat treatment on the solid-state phase transformation and microstructures of Cu_(61.13)Zn_(33.94)Al_(4.93) alloys 被引量:7
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作者 王海燕 刘建华 +1 位作者 彭桂荣 王文魁 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期469-474,共6页
The phase transformation activation energy of the Cu61.13Zn33.94A14.93 alloys, which were treated at 4 GPa and 700 ℃ for 15 minutes, was calculated by means of differential scanning calorimetry curves obtained at var... The phase transformation activation energy of the Cu61.13Zn33.94A14.93 alloys, which were treated at 4 GPa and 700 ℃ for 15 minutes, was calculated by means of differential scanning calorimetry curves obtained at various heating and cooling rates. Then, the effects of high-pressure heat treatments on the solid-state phase transformation and the microstructures of Cu61.13Zn33.94A14.93 alloys were investigated. The results show that high-pressure heat treatments can refine the grains and can change the preferred orientation from (111) to (200) of α phase. Compared with the as-cast alloy, the sample with high-pressure heat treatment has finer grains, lower β'→β and/β→β' transformation temperature and activation energy. Furthermore, we found that high cooling rate favours the formation of fine needle-like α phase in the range of 5-20℃/min. 展开更多
关键词 Cu61.13Zn33.94A14.93 alloy high-pressure heat treatment solid-state phase transformation MICROSTRUCTURES
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High-sensitive state perception method for inverter-fed machine turn insulation based on FrFT-Mel
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作者 Ruitian Fan Xing Lei +3 位作者 Tao Jia Menglong Qin Hao Li Dawei Xiang 《Global Energy Interconnection》 EI CSCD 2024年第2期155-165,共11页
Amidst the swift advancement of new power systems and electric vehicles,inverter-fed machines have progressively materialized as a pivotal apparatus for efficient energy conversion.Stator winding turn insulation failu... Amidst the swift advancement of new power systems and electric vehicles,inverter-fed machines have progressively materialized as a pivotal apparatus for efficient energy conversion.Stator winding turn insulation failure is the root cause of inverter-fed machine breakdown.The online monitoring of turn insulation health can detect potential safety risks promptly,but faces the challenge of weak characteristics of turn insulation degradation.This study proposes an innovative method to evaluate the turn insulation state of inverter-fed machines by utilizing the fractional Fourier transform with a Mel filter(FrFT-Mel).First,the sensitivity of the high-frequency(HF)switching oscillation current to variations in turn insulation was analyzed within the fractional domain.Subsequently,an improved Mel filter is introduced,and its structure and parameters are specifically designed based on the features intrinsic to the common-mode impedance resonance point of the electrical machine.Finally,an evaluation index was proposed for the turn insulation state of inverter-fed machines.Experimental results on a 3kW permanent magnet synchronous machine(PMSM)demonstrate that the proposed FrFT-Mel method significantly enhances the sensitivity of turn insulation state perception by approximately five times,compared to the traditional Fourier transform method. 展开更多
关键词 state perception Turn insulation Switching oscillation Fractional Fourier transform Mel filter
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基于Transformer大规模MIMO的CSI反馈网络
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作者 王昱凯 张志晨 +2 位作者 王荣 李军 何波 《齐鲁工业大学学报》 CAS 2024年第2期1-7,共7页
针对频分双工大规模多输入多输出系统中信道状态信息反馈方法反馈精度低的问题,提出了一种名为CDTransformer的基于Transformer和卷积分解(convolutional decomposition,CD)的CSI反馈网络。CDTransformer将卷积分解融入改进的Transforme... 针对频分双工大规模多输入多输出系统中信道状态信息反馈方法反馈精度低的问题,提出了一种名为CDTransformer的基于Transformer和卷积分解(convolutional decomposition,CD)的CSI反馈网络。CDTransformer将卷积分解融入改进的Transformer结构网络中,在不增加计算复杂度的情况下提升网络性能,并通过对网络的全连接层进行二值化实现轻量级部署。针对用户端功率有限的情况,提出了一种MixedTransformer网络模型。其中编码器采用计算成本较低、结构简单的单层卷积神经网络,而解码器则采用与CDTransformer模型相同的结构。CDTransformer模型融合了Transformer结构和卷积分解,提高了CSI反馈精度并实现轻量级部署。此外,引入了MixedTransformer模型,结合了CDTransformer和卷积神经网络的优点,以在功率有限情况下提供更好的性能。结果显示,相比于CsiTransformer网络模型,CDTransformer网络模型在归一化均方误差和余弦相似度方面分别提高了37.7%和0.2%。 展开更多
关键词 频分双工 大规模MIMO transformER 信道状态信息 卷积神经网络
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Multiple steady state phenomenon in martensitic transformation
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作者 覃文 陈振华 +1 位作者 黄培云 庄应烘 《中国有色金属学会会刊:英文版》 CSCD 2001年第3期319-323,共5页
Based on the basic facts that the martensitic transformation is a physical phenomenon which occurs in non equilibrium conditions and there exists the feedback mechanism in the martensitic transformation, the dynamical... Based on the basic facts that the martensitic transformation is a physical phenomenon which occurs in non equilibrium conditions and there exists the feedback mechanism in the martensitic transformation, the dynamical processes of the isothermal and athermal martensitic transformations were analyzed by using nonlinear theory and a bifurcation theory model was established. It is shown that a multiple steady state phenomenon can take place as austenite is cooled, and the transitions of the steady state temperature between the branches of stable steady states can be considered the transformation from austenite to martensite. This model can estimate the starting temperature of the martensitic transformation and explain some experimental features of the martensitic transformation such as the effects of cooling rate, fluctuation and austenitic grain size on the martensitic transformation. [ 展开更多
关键词 martensitic transformation multiple steady states steady state transition
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Analyzing and Designing Business Processes Management System Based on Transformation of Instantiated Ontology’s State
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作者 YAO Qing WANG Haiyang 《Wuhan University Journal of Natural Sciences》 CAS 2006年第5期1126-1131,共6页
The paper discusses efforts of finding a simple and transparent method to analyze business processes and developing its management system architecture. By introducing ontology and its state, the approach tried to find... The paper discusses efforts of finding a simple and transparent method to analyze business processes and developing its management system architecture. By introducing ontology and its state, the approach tried to find a unified representation and a flexible choreography of business processes. The main idea of the paper is the transformation of ontology's states, which are the most important scenarios of enterprises. The business activity composition, that is, case composition based on an AI technique, Case Based Reason (CBR), which is to solve new problems by retrieving solutions to previous problems, and then store the modified solution. The main interest in CBR relies on that it allows a system to avoid past failures and exploit past successes. 展开更多
关键词 ontology business process management (BPM) case based reason(CBR) state transform
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Coherent State Projection Operator Representation of Symplectic Transformations as a Loyal Representation of Symplectic Group
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作者 FAN Hong-Yi CHEN Jun-Hua 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第8期147-150,共4页
We find that the coherent state projection operator representation of symplectic transformation constitutesa loyal group representation of symplectic group. The result of successively applying squeezing operators on n... We find that the coherent state projection operator representation of symplectic transformation constitutesa loyal group representation of symplectic group. The result of successively applying squeezing operators on numberstate can be easily derived. 展开更多
关键词 COHERENT state PROJECTION operator SYMPLECTIC transformation SQUEEZING OPERATOR
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A generalized Hadamard transformation from new entangled state
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作者 徐兴磊 徐世民 +2 位作者 张运海 李洪奇 王继锁 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期105-109,共5页
A new entangled state |η 0) is proposed by the technique of integral within an ordered product. A generalized Hadamaxd transformation is derived by virtue of η; θ), which plays a role of Hadamard transformation ... A new entangled state |η 0) is proposed by the technique of integral within an ordered product. A generalized Hadamaxd transformation is derived by virtue of η; θ), which plays a role of Hadamard transformation for (a1 sinθ - a2 cosθ) and (a1 cosθ + a2 sin θ). 展开更多
关键词 generalized Hadamard transformation entangled state technique of integral within an ordered product
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Coordinate-Dependent One- and Two-Mode Squeezing Transformation and the Corresponding Squeezed States
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作者 REN Gang SONG Tong-Qiang Department of Physics,Ningbo University,Ningbo 315211,China 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第12期1093-1098,共6页
We introduce the coordinate-dependent one-and two-mode squeezing transformations and discuss theproperties of the corresponding one-and two-mode squeezed states.We show that the coordinate-dependent one-and two-mode s... We introduce the coordinate-dependent one-and two-mode squeezing transformations and discuss theproperties of the corresponding one-and two-mode squeezed states.We show that the coordinate-dependent one-and two-mode squeezing transformations can be constructed by the combination of two transformations,a coordinate-dependentdisplacement followed by the standard squeezed transformation.Such a decomposition turns a nonlinear problem intoa linear one because all the calculations involving the nonlinear one- and two-mode squeezed transformation have beenshown to be able to reduce to those only concerning the standard one- and two-mode squeezed states. 展开更多
关键词 one-and two-mode squeezed states nonlinear Bogoliubov transformations
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SOLID-STATE PHASE TRANSFORMATION OF WELDED METAL IN CONTROL OF WELDING DISTORTION PROCESS
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作者 WangWenxian HuoLixing ZhangYufeng WangDongpo JingHongyang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第1期64-67,共4页
Based on the tests of a build-up welding at plate edge (BWPE) and amulti-layer build-up welding on plate (MBWP), the article studies on the solid-state phasetransformations which affect welding distortion process and ... Based on the tests of a build-up welding at plate edge (BWPE) and amulti-layer build-up welding on plate (MBWP), the article studies on the solid-state phasetransformations which affect welding distortion process and on the influence rule of transformationstarting temperature (TST) of welded metal to the welding residual distortion. The weldingdistortion can be decreased or controlled by the transformation volume expansion caused bysolid-state phase transformation of welded metal during the cooling. The test results of BWPE showthat when TST is at about 190 deg C, the bending distortion of welded specimen is the smallest, andits displacements at free end are decreased to 58 percent and 67 percent compared with those ofconventional welding electrodes A102 and E5015, which TST are less than room temperature and equalto 758 deg C respectively. The test results of MBWP show that when TST were at 100 approx 250 deg C.the welded specimen would appear reversible bending distortion compared with those of A102 andE5015. The maximum deflection value of reversible bending distortion in 8 mm thick plate is -2.94 mmat about 170 deg C of TST. The test results provide a valuable method to decrease or to controlwelding residual distortion. 展开更多
关键词 Solid-state phase transformation transformation starting temperature Weldedjoint Welding distortion
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基于卡尔曼滤波算法优化Transformer模型的锂离子电池健康状态预测方法
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作者 黄煜峰 梁焕超 许磊 《储能科学与技术》 CAS CSCD 北大核心 2024年第8期2791-2802,共12页
回顾了锂离子电池健康状态(state of health,SOH)的预测方法,本文提出了一种基于卡尔曼滤波器(Kalman filter)优化的Transformer网络,利用历史数据预测电池SOH。首先,通过添加高斯噪声、自动编码器重构对电池数据进行预处理,去除电池数... 回顾了锂离子电池健康状态(state of health,SOH)的预测方法,本文提出了一种基于卡尔曼滤波器(Kalman filter)优化的Transformer网络,利用历史数据预测电池SOH。首先,通过添加高斯噪声、自动编码器重构对电池数据进行预处理,去除电池数据中原始噪声并强化数据特征;其次,利用提出的KF-Transformer(Kalman filter-transformer)算法模型提取电池健康状态变化特征,使得Transformer网络能够更好地捕捉电池健康状态的非线性变化;最后,通过线性层完成电池健康状态变化特征到电池健康状态预测的映射,得到锂离子电池健康状态的预测结果。本文使用3个不同充放电策略、不同测试环境下的锂离子电池数据集[分别为美国国家航空航天局(NASA)数据集、马里兰大学CALCE CS2数据集和CALCE CX2数据集]来验证本文提出的锂离子电池健康状态预测算法的鲁棒性和准确性,且本文算法对于SOH不同状态、不同循环次数的预测均具有较好的结果。研究结果显示,本文方法的平均绝对百分比误差(mean absolute percentage error,MAPE)能控制在2%,决定系数(R-square,R2)为0.987,并与多层感知机(MLP,multilayer perceptron)、循环神经网络(RNN,recurrent neura network)、长短时记忆(LSTM,long short-term memory)、门控循环单元(GRU,gated recurrent unit)进行比较,证明了本文方法的优越性。 展开更多
关键词 锂离子电池 电池健康状态 自动编码器 transformer网络 卡尔曼滤波器
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A Generalized Hankel Transformation Derived by Parametrized Entangled State Representations
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作者 FAN Hong-Yi HU Li-Yun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期85-88,共4页
Using the parametrized entangled state representations we have found a generalized Hankel transformationwith the integral kernel being a combination of Bessel functions.This generalized Hankel transformation correspon... Using the parametrized entangled state representations we have found a generalized Hankel transformationwith the integral kernel being a combination of Bessel functions.This generalized Hankel transformation corresponds tothe appropriate quantum mechanical representation transformation. 展开更多
关键词 缠结状态 广义转换 数学 技术性能
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Study Hankel Transforms and Properties of Bessel Function via Entangled State Representation Transformation in Quantum Mechanics
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作者 FAN Hong-Yi WANG Yong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5期819-824,共6页
在 Phys。Lett。一 313 (2003 ) 343 我们发现了自我相互的 Hankeltransformation (HT ) 被在连续统变量的二个纠缠的州的代表之间的变换在量力学表达。在这个工作,我们在量力学经由纠缠的州的表示的转变学习 Hankel 变换和性质 ofBess... 在 Phys。Lett。一 313 (2003 ) 343 我们发现了自我相互的 Hankeltransformation (HT ) 被在连续统变量的二个纠缠的州的代表之间的变换在量力学表达。在这个工作,我们在量力学经由纠缠的州的表示的转变学习 Hankel 变换和性质 ofBessel 功能。 展开更多
关键词 纠缠态表征 HANKEL变换 BESSEL函数 理论物理
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Simple Procedure for Entanglement Transformation of Bipartite Pure States
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作者 WU Chun-Wang CHEN Ping-Xing LI Cheng-Zu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第3期652-654,共3页
<Abstract>An explicit procedure for transforming one bipartite entangled state into another via local operations and classical communication (LOCC) is presented.Our procedure is much simper than the previous one... <Abstract>An explicit procedure for transforming one bipartite entangled state into another via local operations and classical communication (LOCC) is presented.Our procedure is much simper than the previous ones in the sense that,it only involves two steps and the explicit expression of local general measurement used in the procedure can be obtained by solving a set of linear equations,Furthermore,this procedure is still applicable in high dimensional case. 展开更多
关键词 纠缠转换 纯状态 线性方程 通信系统
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Matrix Tensor Product Approach to the Equivalence of Multipartite States under Local Unitary Transformations
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作者 GAO Xiu-Hong S. Alberverio +1 位作者 FEI Shao-Ming WANG Zhi-Xi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2期267-270,共4页
混合的多国参加的量的等价在本地人下面声明单一的转变被学习。为在本地单一的转变下面的非退化的混合的多国参加的量状态的等价的一个标准被介绍。
关键词 矩阵张量 局部整体转化 多量子混合态 张量分解
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Coordinate-Dependent Two-Mode Squeezing Transformations and the Corresponding Squeezed States
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作者 SONG Tong-Qiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期325-329,共5页
我们介绍并列依赖者的二模式的压榨转变并且讨论相应二模式的挤压的状态的性质。
关键词 坐标相关双模叠加转换 叠加态 性质 Bogoliubov换算
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