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英语V+To+Infinitive与V+To+V-ing结构的对比分析
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作者 周芬 《韶关学院学报》 2012年第7期58-62,共5页
英语v+to+infinitive与v+to+v-ing结构极易发生混淆。在句法上,v+to+infinitive结构中的to+infinitive要么是CP,要么是TP,而v+to+v-ing结构中的to+v-ing是介词短语PP。从语义角度来说,我们可以用主动词提示的时间做参照,to+infinitive... 英语v+to+infinitive与v+to+v-ing结构极易发生混淆。在句法上,v+to+infinitive结构中的to+infinitive要么是CP,要么是TP,而v+to+v-ing结构中的to+v-ing是介词短语PP。从语义角度来说,我们可以用主动词提示的时间做参照,to+infinitive所蕴含事件的时间要么发生在主动词时间之后或是与之同时发生,而to v-ing所蕴含的事件可以发生在主动词时间之前,之后或同时发生。另外,与to+infinitive结构不同的是v-ing结构更加倾向强调所发生事件的内部组成成分,所持续的时间和展开的方式等。 展开更多
关键词 v+to+infinitive结构 v+to+v-ing结构 句法 语义
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A Syntactic Study on Bare Infinitive and Infinitival to
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作者 刘静 《海外英语》 2014年第10X期239-240,共2页
Infinitives which consist of bare infinitive and infinitival to are imperative in linguistic studies.And both of the two kinds of infinitives do not indicate person,tense and number.This research aims to analyze the p... Infinitives which consist of bare infinitive and infinitival to are imperative in linguistic studies.And both of the two kinds of infinitives do not indicate person,tense and number.This research aims to analyze the properties,similarities and differences between bare infinitive and infinitival to from the perspective of syntax.Thus,it enables us to attain a uniform characterization of the infinitival to and bare infinitive on the syntactic level and help us to understand these two kinds of infinitives better. 展开更多
关键词 BARE infinitive infinitival to SIMILARITIES differ
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State-Based Opacity Verification of Networked Discrete Event Systems Using Labeled Petri Nets
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作者 Yifan Dong Naiqi Wu Zhiwu Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第5期1274-1291,共18页
The opaque property plays an important role in the operation of a security-critical system,implying that pre-defined secret information of the system is not able to be inferred through partially observing its behavior... The opaque property plays an important role in the operation of a security-critical system,implying that pre-defined secret information of the system is not able to be inferred through partially observing its behavior.This paper addresses the verification of current-state,initial-state,infinite-step,and K-step opacity of networked discrete event systems modeled by labeled Petri nets,where communication losses and delays are considered.Based on the symbolic technique for the representation of states in Petri nets,an observer and an estimator are designed for the verification of current-state and initial-state opacity,respectively.Then,we propose a structure called an I-observer that is combined with secret states to verify whether a networked discrete event system is infinite-step opaque or K-step opaque.Due to the utilization of symbolic approaches for the state-based opacity verification,the computation of the reachability graphs of labeled Petri nets is avoided,which dramatically reduces the computational overheads stemming from networked discrete event systems. 展开更多
关键词 INFINITE SYSTEM SYMBOLIC
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Anomalous Quantum Dynamics in Lossy Nonlocal System
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作者 Liwei Qiao Wei Zhang Kaiye Shi 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第12期1-6,共6页
The non-Hermitian skin effect and edge burst reflect the vital role of spatial boundaries in non-Hermitian systems from both static and dynamic perspectives.In this study,we investigate a non-Hermitian dissipative lat... The non-Hermitian skin effect and edge burst reflect the vital role of spatial boundaries in non-Hermitian systems from both static and dynamic perspectives.In this study,we investigate a non-Hermitian dissipative lattice with nonlocal coupling and demonstrate many interesting static and dynamic phenomena.In the case of global coupling with all sites coupled with each other,we observe anomalous hopping resonance,where a quantum walker initially placed at a single site almost completely escapes from the boundary of the system regardless of its initial position.In the case of non-global coupling,which is infinite-range coupling,the interplay between nonlocal hopping and the non-Hermitian skin effect results in the emergence of local bulk modes exhibiting a multipartite density distribution.The presence of local bulk modes induces the nontrivial dynamics of a quantum walker,which features multiple peaks of lost probability in spatially separated domains.Our findings demonstrate unique properties induced by nonlocal coupling in non-Hermitian systems. 展开更多
关键词 COUPLING nontrivial INFINITE
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THE SCHUR TEST OF COMPACT OPERATORS
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作者 Qijian KANG Maofa WANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期2041-2050,共10页
Infinite matrix theory is an important branch of function analysis.Every linear operator on a complex separable infinite dimensional Hilbert space corresponds to an infinite matrix with respect a orthonormal base of t... Infinite matrix theory is an important branch of function analysis.Every linear operator on a complex separable infinite dimensional Hilbert space corresponds to an infinite matrix with respect a orthonormal base of the space,but not every infinite matrix corresponds to an operator.The classical Schur test provides an elegant and useful criterion for the boundedness of linear operators,which is considered a respectable mathematical accomplishment.In this paper,we prove the compact version of the Schur test.Moreover,we provide the Schur test for the Schatten class S_(2).It is worth noting that our main results can be applicable to the general matrix without limitation on non-negative numbers.We finally provide the Schur test for compact operators from l_(p) into l_(q). 展开更多
关键词 Schur test compact operator infinite matrix
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Determination of the critical rainfall of runoff-initiated debris flows by the perspective of physical mechanics and Shields stress
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作者 MA Chao ZHU Yongtai +3 位作者 LU Lu DU Cui LYU Liqun DONG Jie 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1160-1173,共14页
The critical rainfall of runoff-initiated debris flows is utmost importance for local early hazard forecasting.This paper presents research on the critical rainfall of runoff-initiated debris flows through comparisons... The critical rainfall of runoff-initiated debris flows is utmost importance for local early hazard forecasting.This paper presents research on the critical rainfall of runoff-initiated debris flows through comparisons between slope gradients and three key factors,including topographic contributing area,dimensionless discharge,and Shields stress.The rainfall amount was estimated by utilizing in-situ rainfall records and a slope-dependent Shields stress model was created.The created model can predict critical Shields stress more accurately than the other two models.Furthermore,a new dimensionless discharge equation was proposed based on the corresponding discharge-gradient datasets.The new equation,along with factors such as contributing area above bed failure sites,channel width,and mean diameter of debris flow deposits,predicts a smaller rainfall amount than the in-situ measured records.Although the slope-dependent Shields stress model performs well and the estimated rainfall amount is lower than the in-situ records,the sediment initiation in the experiments falls within sheet flow regime due to a large Shields stress.Therefore,further sediment initiation experiments at a steeper slope range are expected in the future to ensure that the sediment transport belongs to mass failure regime characterized by a low level of Shields stress.Finally,a more accurate hazard forecast on the runoff-initiated debris flow holds promise when the corresponding critical slope-dependent dimensionless discharge of no motion,fluvial sediment transport,mass flow regime,and sheet flow regime are considered. 展开更多
关键词 Infinite slope stability Shields stress Contributing area-slope gradient Rainfall back estimation
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Ultrasonic wind velocity measurement based on DSP 被引量:10
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作者 唐慧强 黄惟一 +1 位作者 李萍 吕清华 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期20-23,共4页
Ultrasonic transmitting, receiving and amplifying circuits are designed. Thereceived signals are sampled with the high speed ADC (analog-to-digital converter), and dealt withthe DSP (digital signal processing). A forw... Ultrasonic transmitting, receiving and amplifying circuits are designed. Thereceived signals are sampled with the high speed ADC (analog-to-digital converter), and dealt withthe DSP (digital signal processing). A forward-backward IIR (infinitive impulse response) filterwith no delay is designed to filter the sampled data, and series A and B are achieved by narrow andwide band filtering, respectively. In series A, the start point of the cycle first exceeding thethreshold is calculated accuratelyby interpolation, and the start cycle is detected by fittingcycles in series A and its inversion A' to cycles in B with variance analysis. Therefore, the startpoint of the start cycle is calculated precisely. By deriving the relationships between the traveltime in the opposite directions of three axes and the airflow velocities, the wind velocity anddirection are calculated. Experiments show that the reliability and the precision are improved, andthe circuits are simplified. 展开更多
关键词 ULTRASONICS IIR (infinitive impulse response) filter DSP (digital signalprocessing) wind velocity
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A Remark on the Affine Coordinates for KdV Tau-Functions
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作者 FU Zhi-peng 《Chinese Quarterly Journal of Mathematics》 2024年第3期324-330,共7页
We give a proof of an explicit formula for affine coodinates of points in the Sato’s infinite Grassmannian corresponding to tau-functions for the KdV hierarchy.
关键词 Sato’s infinite Grassmannian KdV hierarchy Affine coordinates
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New Raw Materials Ignite the Singularity of Cosmetic Innovation
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作者 Yi Yao Yang Xiaofeng 《China Detergent & Cosmetics》 CAS 2024年第3期6-8,共3页
As traced by the Big Bang theory,the starting point of the universe,is called the“Singularity”in Da Ci Hai,an unabridged,comprehensive dictionary.According to cosmological reasoning,the singularity has an infinite d... As traced by the Big Bang theory,the starting point of the universe,is called the“Singularity”in Da Ci Hai,an unabridged,comprehensive dictionary.According to cosmological reasoning,the singularity has an infinite density of matter,an infinite curvature of space and time,and it is invisible and infinite.These characteristics are analogous to the human imagination at the level of innovation.For the innovation of cosmetic raw materials,there is also the possibility of infinite evolution.For example,in recent years,the scientific research in cosmetic industry the for promoting upgrade in raw materials is quite proactive.From the raw material enterprises,down to the brand company,the investment in raw material innovation is also strengthened at a visible rate. 展开更多
关键词 INFINITE VISIBLE SINGULARITY
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Finite Words,Infinite Wisdom
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作者 DENG DI 《China Today》 2024年第5期70-72,共3页
As picture books gain popularity,they create a bridge between China and the rest of the world.
关键词 FINITE INFINITE BRIDGE
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Three Selenate New Organotin (IV) and Magnesium Chloride Adducts: Synthesis and Spectroscopic Study
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作者 Boucar Diouf Waly Diallo +3 位作者 Daouda Ndoye Bogou Ndiaye Mamadou Ba Mamadou Sidibé 《Journal of Environmental Science and Engineering(B)》 CAS 2024年第6期267-273,共7页
By allowing H2SeO4,Cy2NH,CyNH2 or Bz2NH to react respectively with SnPh3Cl(in methanol),SnPh2Cl2(in water+methanol)and MgCl2·6H2O(in methanol)in specific ratios,the studied complexes are obtained.The suggested st... By allowing H2SeO4,Cy2NH,CyNH2 or Bz2NH to react respectively with SnPh3Cl(in methanol),SnPh2Cl2(in water+methanol)and MgCl2·6H2O(in methanol)in specific ratios,the studied complexes are obtained.The suggested structures are discrete and polymer,the environment of the tin center being trans trigonal bipyramidal(compound 1),tetrahedral(compound 2)and octahedral(compound 3),the anions behaving as a bidentate selenate. 展开更多
关键词 BIDENTATE discrete structures SnPhCl3 SnPh2Cl2 or MgCl2·6H2O react SELENATE infinite chain hydrogen bonds monochelating monodentate trigonal bipyramidal or tetrahedral environments C2V symmetry magnesium.
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A New Proof for Congruent Number’s Problem via Pythagorician Divisors
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作者 Léopold Dèkpassi Keuméan François Emmanuel Tanoé 《Advances in Pure Mathematics》 2024年第4期283-302,共20页
Considering Pythagorician divisors theory which leads to a new parameterization, for Pythagorician triplets ( a,b,c )∈ ℕ 3∗ , we give a new proof of the well-known problem of these particular squareless numbers n∈ ℕ... Considering Pythagorician divisors theory which leads to a new parameterization, for Pythagorician triplets ( a,b,c )∈ ℕ 3∗ , we give a new proof of the well-known problem of these particular squareless numbers n∈ ℕ ∗ , called congruent numbers, characterized by the fact that there exists a right-angled triangle with rational sides: ( A α ) 2 + ( B β ) 2 = ( C γ ) 2 , such that its area Δ= 1 2 A α B β =n;or in an equivalent way, to that of the existence of numbers U 2 , V 2 , W 2 ∈ ℚ 2∗ that are in an arithmetic progression of reason n;Problem equivalent to the existence of: ( a,b,c )∈ ℕ 3∗ prime in pairs, and f∈ ℕ ∗ , such that: ( a−b 2f ) 2 , ( c 2f ) 2 , ( a+b 2f ) 2 are in an arithmetic progression of reason n;And this problem is also equivalent to that of the existence of a non-trivial primitive integer right-angled triangle: a 2 + b 2 = c 2 , such that its area Δ= 1 2 ab=n f 2 , where f∈ ℕ ∗ , and this last equation can be written as follows, when using Pythagorician divisors: (1) Δ= 1 2 ab= 2 S−1 d e ¯ ( d+ 2 S−1 e ¯ )( d+ 2 S e ¯ )=n f 2;Where ( d, e ¯ )∈ ( 2ℕ+1 ) 2 such that gcd( d, e ¯ )=1 and S∈ ℕ ∗ , where 2 S−1 , d, e ¯ , d+ 2 S−1 e ¯ , d+ 2 S e ¯ , are pairwise prime quantities (these parameters are coming from Pythagorician divisors). When n=1 , it is the case of the famous impossible problem of the integer right-angled triangle area to be a square, solved by Fermat at his time, by his famous method of infinite descent. We propose in this article a new direct proof for the numbers n=1 (resp. n=2 ) to be non-congruent numbers, based on an particular induction method of resolution of Equation (1) (note that this method is efficient too for general case of prime numbers n=p≡a ( ( mod8 ) , gcd( a,8 )=1 ). To prove it, we use a classical proof by induction on k , that shows the non-solvability property of any of the following systems ( t=0 , corresponding to case n=1 (resp. t=1 , corresponding to case n=2 )): ( Ξ t,k ){ X 2 + 2 t ( 2 k Y ) 2 = Z 2 X 2 + 2 t+1 ( 2 k Y ) 2 = T 2 , where k∈ℕ;and solutions ( X,Y,Z,T )=( D k , E k , f k , f ′ k )∈ ( 2ℕ+1 ) 4 , are given in pairwise prime numbers.2020-Mathematics Subject Classification 11A05-11A07-11A41-11A51-11D09-11D25-11D41-11D72-11D79-11E25 . 展开更多
关键词 Prime Numbers-Diophantine Equations of Degree 2 & 4 Factorization Greater Common Divisor Pythagoras Equation Pythagorician Triplets Congruent Numbers Inductive Demonstration Method Infinite Descent BSD Conjecture
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Infinitely Many Solutions and a Ground-State Solution for Klein-Gordon Equation Coupled with Born-Infeld Theory
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作者 Fangfang Huang Qiongfen Zhang 《Journal of Applied Mathematics and Physics》 2024年第4期1441-1458,共18页
In this paper, we intend to consider a kind of nonlinear Klein-Gordon equation coupled with Born-Infeld theory. By using critical point theory and the method of Nehari manifold, we obtain two existing results of infin... In this paper, we intend to consider a kind of nonlinear Klein-Gordon equation coupled with Born-Infeld theory. By using critical point theory and the method of Nehari manifold, we obtain two existing results of infinitely many high-energy radial solutions and a ground-state solution for this kind of system, which improve and generalize some related results in the literature. 展开更多
关键词 Klein-Gordon Equation Born-Infeld Theory Infinitely Many Solutions Ground-State Solution Critical Point Theory
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Explicit solution of diffusion master equation under the action of linear resonance force via the thermal entangled state representation 被引量:3
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作者 姚飞 王继锁 徐天牛 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期98-101,共4页
Using the well-behaved features of the thermal entangled state representation, we solve the diffusion master equation under the action of a linear resonance force, and then obtain the infinitive operator-sum represent... Using the well-behaved features of the thermal entangled state representation, we solve the diffusion master equation under the action of a linear resonance force, and then obtain the infinitive operator-sum representation of the density operator. This approach may also be effective for treating other master equations. Moreover, we find that the initial pure coherent state evolves into a mixed thermal state after passing through the diffusion process under the action of the linear resonance force. 展开更多
关键词 diffusion process linear resonance force thermal state representation infinitive operator-sum representation
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Analytical and numerical investigations of displaced thermal state evolutions in a laser process 被引量:2
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作者 杜传勋 孟祥国 +1 位作者 张冉 王继锁 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第12期102-108,共7页
We investigate how displaced thermal states (DTSs) evolve in a laser channel. Remarkably, the initial DTS, an example of a mixed state, still remains mixed and thermal. At long times, they finally decay to a highly ... We investigate how displaced thermal states (DTSs) evolve in a laser channel. Remarkably, the initial DTS, an example of a mixed state, still remains mixed and thermal. At long times, they finally decay to a highly classical thermal field only related to the laser parameters κ and g. The normal ordering product of density operator of the DTS in the laser channel leads to obtaining the analytical time-evolution expressions of the photon number, Wigner function, and von Neumann entropy. Also, some interesting results are presented via numerically investigating these explicit time-dependent expressions. 展开更多
关键词 displaced thermal state laser process infinitive operator-sum representation photon number Wigner function von Neumann entropy
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自适应滤波器在超宽带穿墙雷达中的应用研究
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作者 吴建斌 凌毓涛 +1 位作者 吴建平 王振亚 《计算机工程与应用》 CSCD 2014年第16期202-205,共4页
作为一种新型探测和定位墙后人体目标的方法,超宽带穿墙雷达在军事和民用多个领域得到了广泛的应用。由于目标信号经常被强背景噪声所淹没,为实现动目标检测,需寻求一种有效的背景相消方法以凸显动目标信号,提高动目标检测和定位的精度... 作为一种新型探测和定位墙后人体目标的方法,超宽带穿墙雷达在军事和民用多个领域得到了广泛的应用。由于目标信号经常被强背景噪声所淹没,为实现动目标检测,需寻求一种有效的背景相消方法以凸显动目标信号,提高动目标检测和定位的精度。在研究回波信号特点的基础上,考虑到无限冲击响应(IIR)滤波器和自适应滤波器的优点,提出采用基于IIR的自适应滤波器背景噪声相消的方法,抑制回波信号中的噪声。为验证方法的有效性,采用该方法对利用SIR20雷达收集的实测数据进行了相关处理。从结果看,该方法能有效抑制背景噪声,凸显目标信号,为目标的检测和定位奠定了良好的基础。 展开更多
关键词 超宽带穿墙雷达 自适应 无线冲击响应 INFINITE IMPULSE Response(IIR)
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浅谈巧学动词的非限定形式
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作者 陈桂娟 《科技信息》 2006年第S3期123-124,共2页
动词有一种不受主语限制的形式,叫做动词的非限定形式(Non- Finite Forms of the Verb)。这种形式不能独立作谓语.所以也叫非谓语动词.但可以和助动词或情态动词等构成谓语,还可以在句子中充当主语、宾语、定语、状语、表语等。其形... 动词有一种不受主语限制的形式,叫做动词的非限定形式(Non- Finite Forms of the Verb)。这种形式不能独立作谓语.所以也叫非谓语动词.但可以和助动词或情态动词等构成谓语,还可以在句子中充当主语、宾语、定语、状语、表语等。其形式有三种:动名词、分词、不定式。中学英语教材从初中到高中都涉及非谓语动词的教学内容。尽管教师采取了分散难点、各个攻破的方法教学该语法项目,但学生仍然搞不清三种非谓语动词的区别,在学习、理解及运用此知识点时感到困难。 展开更多
关键词 Non-Finite VERBS infinitive GERUND PRESENT Partici
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Research on Post-classical Narrative Focalization in The Love Wife
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作者 郭丽莉 《海外英语》 2013年第16期171-172,共2页
The Love Wife is considered to be a breakthrough of Gish Jen either in theme and narrative techniques. While, as the critical distinguished narrative technique from the perspective of Post-classical Narratology, the i... The Love Wife is considered to be a breakthrough of Gish Jen either in theme and narrative techniques. While, as the critical distinguished narrative technique from the perspective of Post-classical Narratology, the infinitive internal focalization will be analyzed in this paper so as to investigate the five protagonists'search for their own identity and eagerness to achieve the acknowledge both from their family and the whole society. Furthermore, the author's own view in breaking up the barrier and discrimination around the world is also well-illustrated. 展开更多
关键词 infinitive internal focalization IDENTITY
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WSP系统与辨识
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作者 陈亚陵 《厦门大学学报(自然科学版)》 CAS 1988年第1期1-7,共7页
本文把投影算子的加权和表示方法引入无穷维线性系统,产生投影加权和系统,即简称为WSP系统,为无穷维系统辨识问题提供一种方便的模型结构方式,文中讨论了WSP系统的产生过程以及其系统辨识问题.
关键词 WSP systems Infinite dimensional IDENTIFICATION
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New approach for deriving the exact time evolution of the density operator for a diffusive anharmonic oscillator and its Wigner distribution function
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作者 孟祥国 王继锁 梁宝龙 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期146-151,共6页
Using thermal entangled state representation,we solve the master equation of a diffusive anharmonic oscillator(AHO) to obtain the exact time evolution formula for the density operator in the infinitive operator-sum ... Using thermal entangled state representation,we solve the master equation of a diffusive anharmonic oscillator(AHO) to obtain the exact time evolution formula for the density operator in the infinitive operator-sum representation.We present a new evolution formula of the Wigner function(WF) for any initial state of the diffusive AHO by converting the WF calculation into an overlap between two pure states in an enlarged Fock space.It is found that this formula is very convenient in investigating the WF's evolution of any known initial state.As applications,this formula is used to obtain the evolution of the WF for a coherent state and the evolution of the photon-number distribution of diffusive AHOs. 展开更多
关键词 diffusive anharmonic oscillator thermal entangled state representation infinitive operator-sum representation Wigner function
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