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RDF(S)模型到关系数据库模式的转换 被引量:1
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作者 吕艳辉 《计算机工程》 CAS CSCD 北大核心 2011年第9期65-67,共3页
针对资源描述框架和资源描述框架模式(RDF(S))的数据管理问题,提出一种RDF(S)模型到关系数据库模式的转换方法。在对RDF(S)模型和关系数据库模式进行形式化定义的基础上,给出RDF(S)模型到关系数据库模式的转换规则和算法,设计并实现相... 针对资源描述框架和资源描述框架模式(RDF(S))的数据管理问题,提出一种RDF(S)模型到关系数据库模式的转换方法。在对RDF(S)模型和关系数据库模式进行形式化定义的基础上,给出RDF(S)模型到关系数据库模式的转换规则和算法,设计并实现相应的转换系统,通过实验验证该转换方法的可行性和有效性。 展开更多
关键词 语义WEB 资源描述框架 资源描述框架模式 关系数据库 RDF(s)模型
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随机过程理论在库存管理中的应用——对连续型和离散型(s,Q)模型的求解 被引量:1
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作者 郁宇卫 《物流科技》 2009年第12期26-29,共4页
基于随机过程理论对物流活动中的库存管理进行优化。在传统的市场需求固定的基础上对顾客需求是随机的情形进行分析,推导模型并进行求解。现代库存管理追求的是效益最大化(或成本最低化),以,s,Q,模型为例,分别对需求是连续的和离散的两... 基于随机过程理论对物流活动中的库存管理进行优化。在传统的市场需求固定的基础上对顾客需求是随机的情形进行分析,推导模型并进行求解。现代库存管理追求的是效益最大化(或成本最低化),以,s,Q,模型为例,分别对需求是连续的和离散的两种情况以成本最低为目标函数进行建模,最后通过算例分析得出库存最优方案。 展开更多
关键词 现代库存管理 随机过程理论 (s Q)模型
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基于服务水平的港口关键备件库存模型研究 被引量:1
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作者 王玖河 杨柳青 《企业经济》 北大核心 2015年第4期145-148,共4页
港口备件种类繁多、价值差异大、资金占用量高高。科学合理的备件库存管理,对提高港口的通过能力和改善其服务水平具有重要的现实意义。本文提出了基于港口备件的"供应定位模型",对港口的库存备件进行分类管理。经研究发现,... 港口备件种类繁多、价值差异大、资金占用量高高。科学合理的备件库存管理,对提高港口的通过能力和改善其服务水平具有重要的现实意义。本文提出了基于港口备件的"供应定位模型",对港口的库存备件进行分类管理。经研究发现,关键备件对港口的影响大、供应难度高且占用大量资金金,针对关键备件库存管理方法的研究,有助于实现港口备件库存管理的合理化以及库存成本最小化。本文通过建立基于服务水平的(r,S)模型,与排队论相结合,寻求港口关键备件的最优库存控制方案,为港口备件库存管理提供决策和参考依据。 展开更多
关键词 港口备件 供应定位模型 服务水平 (r s)模型
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FUZZY ROBUST H_∞ CONTROL OF UNCERTAIN NONLINEAR SYSTEM WITH TIME-DEALY 被引量:3
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作者 刘亚 胡寿松 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第2期123-126,共4页
This paper addresses the problem of the fuzzy H ∞state feedback control for a class of uncertain nonlinear systems with time delay. The Takagi Sugeno (T S) mo del with time delay and parameter uncertainties is ... This paper addresses the problem of the fuzzy H ∞state feedback control for a class of uncertain nonlinear systems with time delay. The Takagi Sugeno (T S) mo del with time delay and parameter uncertainties is adopted for modeling of nonlinear system. The systematic design procedure for the fuzzy robust controller based on linear matrix inequality (LMI) is given. Some sufficient conditions are derived for the existence of fuzzy H ∞ state feedback controllers such that the closed loop system is asymptotically stable and the effect of the disturbance input on controlled output is reduced to a prescribed level. An example is given to demonstrate the effectiveness of the proposed method. 展开更多
关键词 UNCERTAINTY time delay T s fuzzy model linear matrix inequality (LMI)
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Rock critical porosity inversion and S-wave velocity prediction 被引量:3
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作者 张佳佳 李宏兵 姚逢昌 《Applied Geophysics》 SCIE CSCD 2012年第1期57-64,116,共9页
A critical porosity model is often used to calculate the dry frame elastic modulus by the rock critical porosity value which is affected by many factors. In practice it is hard for us to obtain an accurate critical po... A critical porosity model is often used to calculate the dry frame elastic modulus by the rock critical porosity value which is affected by many factors. In practice it is hard for us to obtain an accurate critical porosity value and we can generally take only an empirical critical porosity value which often causes errors. In this paper, we propose a method to obtain the rock critical porosity value by inverting P-wave velocity and applying it to predict S-wave velocity. The applications of experiment and log data both show that the critical porosity inversion method can reduce the uncertainty resulting from using an empirical value in the past and provide the accurate critical porosity value for predicting S-wave velocity which significantly improves the prediction accuracy. 展开更多
关键词 Gassmann's equations dry frame critical porosity critical porosity model s-wave velocity prediction
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T-S-fuzzy-model-based quantized control for nonlinear networked control systems
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作者 褚红燕 费树岷 +1 位作者 陈海霞 翟军勇 《Journal of Southeast University(English Edition)》 EI CAS 2010年第1期137-141,共5页
In order to overcome data-quantization, networked-induced delay, network packet dropouts and wrong sequences in the nonlinear networked control system, a novel nonlinear networked control system model is built by the ... In order to overcome data-quantization, networked-induced delay, network packet dropouts and wrong sequences in the nonlinear networked control system, a novel nonlinear networked control system model is built by the T-S fuzzy method. Two time-varying quantizers are added in the model. The key analysis steps in the method are to construct an improved interval-delay-dependent Lyapunov functional and to introduce the free-weighting matrix. By making use of the parallel distributed compensation technology and the convexity of the matrix function, the improved criteria of the stabilization and stability are obtained. Simulation experiments show that the parameters of the controllers and quantizers satisfying a certain performance can be obtained by solving a set of LMIs. The application of the nonlinear mass-spring system is provided to show that the proposed method is effective. 展开更多
关键词 T-s fuzzy model linear matrix inequalities(LMIs quantizers
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GM(1,1)-星野法沉降预测模型研究与应用 被引量:5
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作者 朱婧 洪宝宁 +1 位作者 刘鑫 常二阳 《河北工程大学学报(自然科学版)》 CAS 2018年第1期62-65,共4页
围绕目前高速公路路基沉降预测精度不高,预测方法适用性不强等问题,基于组合预测理论,借助MATLAB计算软件,将基于灰色理论的GM(1,1)预测模型和星野法沉降预测模型线性组合,以组合预测误差的平方和最小为标准确定两种预测方法的权重系数... 围绕目前高速公路路基沉降预测精度不高,预测方法适用性不强等问题,基于组合预测理论,借助MATLAB计算软件,将基于灰色理论的GM(1,1)预测模型和星野法沉降预测模型线性组合,以组合预测误差的平方和最小为标准确定两种预测方法的权重系数,提出GM(1,1)-星野法组合预测模型。结合广东某高速公路施工期以及运营期路基实测沉降数据,GM(1,1)-星野法组合预测模型预测结果较两种方法单独预测结果具有更高的预测精度,工程适用性更强。 展开更多
关键词 GM(1 1)模型s星野法 MATLAB计算s组合模型 沉降预测
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Predicting the Rainfall-Triggered Landslides in a Forested Mountain Region Using TRIGRS Model 被引量:10
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作者 Dongyeob KIM Sangjun IM +2 位作者 Sang Ho LEE Youngjoo HONG Kyung-Sub CHA 《Journal of Mountain Science》 SCIE CSCD 2010年第1期83-91,共9页
Landslides are natural disasters which can pose a serious threat to human and property in many areas around the world. The Transient Rainfall Infiltration and Grid-based Regional Slope-stability (TRIGRS) model was use... Landslides are natural disasters which can pose a serious threat to human and property in many areas around the world. The Transient Rainfall Infiltration and Grid-based Regional Slope-stability (TRIGRS) model was used to investigate the rainfall-induced shallow landslides in a forested mountain region, Korea. Various input data for TRIGRS model include time-varying rainfall, topographic characteristics, soil depth, material strength, and hydraulic properties. A series of calculations were conducted in determining the slope stability over the Jangheung region in Korea during the storm occurred on August 6, 1998. The results show that TRIGRS model captured about 64.1% of landslides that were extracted from the IKONOS2 imageries. The model demonstrated how the factor of safety changed with time during a storm considering both the transient and spatial responses of pore water pressure in its slope stability calculation. 展开更多
关键词 TRIGRs LANDsLIDEs IKONOs2 safetyfactor slope stability Korea
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随机利率下定期寿险趸交纯保费模型
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作者 汤恒洲 刘洪 《辽宁科技大学学报》 CAS 2010年第3期279-284,共6页
定期寿险是人寿保险体系的重要组成部分,其合理的定价受到越来越多的关注。本文依据时间序列理论,基于利息力序列条件异方差的ARMA(p,q)-GARCH(r,s)模型,针对固定保险金额的定期寿险,建立了随机利率下的定期寿险趸交纯保费的数学模型,... 定期寿险是人寿保险体系的重要组成部分,其合理的定价受到越来越多的关注。本文依据时间序列理论,基于利息力序列条件异方差的ARMA(p,q)-GARCH(r,s)模型,针对固定保险金额的定期寿险,建立了随机利率下的定期寿险趸交纯保费的数学模型,并通过实例分析说明该模型的合理性。 展开更多
关键词 随机利率 趸交纯保费 ARMAARMA(p q)-GARCH(r s)模型 定期寿险
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Min-max fuzzy model predictive tracking control of boiler-turbine system for ultra-supercritical units 被引量:1
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作者 Chen Chen Pan Lei Kwang Y.Lee 《Journal of Southeast University(English Edition)》 EI CAS 2021年第1期42-51,共10页
To improve the control performance of nonlinear ultra-supercritical(USC)thermal power units,an improved min-max fuzzy model predictive tracking control(FMPTC)strategy is proposed.First,a T-S fuzzy model is established... To improve the control performance of nonlinear ultra-supercritical(USC)thermal power units,an improved min-max fuzzy model predictive tracking control(FMPTC)strategy is proposed.First,a T-S fuzzy model is established to approximate the dynamics of the nonlinear boiler-turbine system.Then,based on an extended fuzzy model containing state variables and output variables,a min-max FMPTC is derived for output regulation while ensuring the closed-loop system stability and the inputs in their given constraints.For greater controller design freedom,the developed controller adopts a new state-and output-based objective function.In addition,the observer estimation error is regarded as a bounded disturbance,ensuring the stability of the entire closed-loop control system.Simulation results on a 1000 MW USC boiler-turbine model illustrate the effectiveness of the proposed approach. 展开更多
关键词 ultra-supercritical boiler-turbine system T-s model min-max model predictive control output tracking linear matrix inequality
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The spring prediction barrier in ENSO hindcast experiments using the FGOALS-g model 被引量:2
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作者 严厉 俞永强 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第6期1093-1104,共12页
The Flexible Global Ocean-Atmosphere-Land System Model-gamil (FGOALS-g) was used to study the spring prediction barrier (SPB) in an ensemble system. This coupled model was developed and maintained at the State Key Lab... The Flexible Global Ocean-Atmosphere-Land System Model-gamil (FGOALS-g) was used to study the spring prediction barrier (SPB) in an ensemble system. This coupled model was developed and maintained at the State Key Laboratory of Atmospheric Sciences and Geophysical Fluid Dynamics (LASG). There are two steps in our hindcast experiments. The first is to integrate the coupled model continuously with sea surface temperature (SST) nudging, from 1971 to 2006. The second is to carry out a series of one-year hindcasts without SST nudging, by adopting initial values from the first step on January 1 st , April 1st , July 1st , and October 1st , from 1982 to 2005. We generate 10 ensemble members for a particular start date (1st ) by choosing different atmospheric and land conditions around the hindcast start date (1st through 10th ). To estimate the predicted SST, two methods are used: (1) Anomaly Correlation Coefficient and its rate of decrease; and (2) Talagrand distribution and its standard deviation. Results show that FGOALS-g offers a reliable ensemble system with realistic initial atmospheric and oceanic conditions, and high anomaly correlation (>0.5) within 6 month lead time. Further, the ensemble approach is effective, in that the anomaly correlation of ensemble mean is much higher than that of most individual ensemble members. The SPB exists in the FGOALS-g ensemble system, as shown by anomaly correlation and equal likelihood. Nevertheless, the role of the ensemble mean in reducing the SPB of ENSO prediction is significant. The rate of decrease of the ensemble mean is smaller than the largest deviations by 0.04-0.14. At the same time, the ensemble system "equal likelihood" declines during spring. An ensemble mean helps give a correct prediction direction, departing from largely-deviated ensemble members. 展开更多
关键词 spring prediction barrier ensemble ENsO hindcast experiments equal likelihood
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Guaranteed Cost Control for Uncertain Nonlinear Time-Delay Neutral Systems Based on T-S Fuzzy Model 被引量:1
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作者 GUO Xi-jin YAN Jun-rong WU Zhong-qiang 《Journal of China University of Mining and Technology》 EI 2005年第3期241-246,共6页
The problem of guaranteed cost fuzzy controller is studied for a class of nonlinear time-delay neutral sys-tems with norm-bounded uncertainty based on T-S model. The sufficient conditions are first derived for the exi... The problem of guaranteed cost fuzzy controller is studied for a class of nonlinear time-delay neutral sys-tems with norm-bounded uncertainty based on T-S model. The sufficient conditions are first derived for the existenceof guaranteed cost fuzzy controllers. These sufficient conditions are equivalent to a kind of linear matrix inequalities.Furthermore, a convex optimization problem with LMI constraints is formulated to design the optimal guaranteedcost controller. 展开更多
关键词 T-s model UNCERTAINTIEs neutral system guaranteed cost control linear matrix inequalities
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Rare Decay Process K→πv in Three-Site Higgsless Model
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作者 LIU Wei YUE Chong-Xing WANG Yong-Zhi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第2期305-309,共5页
Rare decay processes K→πvv^- and KL→π^0vv^- are considered in the framework of three-site Higgsless model. The contributions of this new physics model to these two decay processes come from the new heavy gauge bos... Rare decay processes K→πvv^- and KL→π^0vv^- are considered in the framework of three-site Higgsless model. The contributions of this new physics model to these two decay processes come from the new heavy gauge bosons and the correction terms for the couplings of the ordinary gauge bosons with fermions. Our numerical results show that the branching ratios of these two decay processes can be enhanced by 40% and 50% relative to those predicted by the standard model. 展开更多
关键词 the three-site Higgsless model rare decay branching ratio new physics
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Aspect-Level Opinion Mining of Online Customer Reviews
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作者 徐学可 程学旗 +2 位作者 谭松波 刘悦 沈华伟 《China Communications》 SCIE CSCD 2013年第3期25-41,共17页
This paper focuses on how to improve aspect-level opinion mining for online customer reviews. We first propose a novel generative topic model, the Joint Aspect/Sentiment (JAS) model, to jointly extract aspects and asp... This paper focuses on how to improve aspect-level opinion mining for online customer reviews. We first propose a novel generative topic model, the Joint Aspect/Sentiment (JAS) model, to jointly extract aspects and aspect-dependent sentiment lexicons from online customer reviews. An aspect-dependent sentiment lexicon refers to the aspect-specific opinion words along with their aspect-aware sentiment polarities with respect to a specific aspect. We then apply the extracted aspectdependent sentiment lexicons to a series of aspect-level opinion mining tasks, including implicit aspect identification, aspect-based extractive opinion summarization, and aspect-level sentiment classification. Experimental results demonstrate the effectiveness of the JAS model in learning aspectdependent sentiment lexicons and the practical values of the extracted lexicons when applied to these practical tasks. 展开更多
关键词 online customer reviews aspectlevel opinion mining aspect-dependent sentiment lexicon Joint Aspect/sentiment model
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Properties of Linear Entropy in k-Photon Jaynes-Cummings Model with Stark Shift and Kerr-Like Medium
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作者 廖庆洪 Muhammad Ashfaq Ahmad +1 位作者 王月媛 刘树田 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第5期931-936,共6页
The time evolution of the linear entropy of an taking into consideration Stark shift and Kerr-like medium. atom in k-photon daynes-Cummings model is investigated The effect of both the Stark shift and Kerr-like medium... The time evolution of the linear entropy of an taking into consideration Stark shift and Kerr-like medium. atom in k-photon daynes-Cummings model is investigated The effect of both the Stark shift and Kerr-like medium on the linear entropy is analyzed using a numerical technique for the field initially in coherent state and in even coherent state. The results show that the presence of the Kerr-like medium and Stark shift has an important effect on the properties of the entropy and entanglement. It is also shown that the setting of the initial state plays a significant role in the evolution of the linear entropy and entanglement. 展开更多
关键词 k-photon Jaynes Cummings model linear entropy stark shift Kerr-like medium
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Entropy and Entanglement in Master Equation of Effective Hamiltonian for Jaynes-Cummings Model
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作者 H.A.Hessian F.A.Mohammed A.-B.A.Mohamed 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第4期723-728,共6页
In this paper, we analytically solve the master equation for Jaynes-Cummings model in the dispersive regime including phase damping and the field is assumed to be initially in a superposition of coherent states. Using... In this paper, we analytically solve the master equation for Jaynes-Cummings model in the dispersive regime including phase damping and the field is assumed to be initially in a superposition of coherent states. Using an established entanglement measure based on the negativity of the eigenvalues of the partially transposed density matrix we find a very strong sensitivity of the maximally generated entanglement to the amount of phase damping. Qualitatively this behavior is also reflected in alternative entanglement measures, but the quantitative agreement between different measures depends on the chosen noise model The phase decoherence for this model results in monotonic increase in the total entropy while the atomic sub-entropy keeps its periodic behaviour without any effect. 展开更多
关键词 ENTANGLEMENT phase damping master equation superposition state
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Pseudo-invariant Eigen-Operator Method for Solving Field-Intensity-Dependent Jaynes-Cummings Model
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作者 俞挞汐 范洪义 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第2期257-260,共4页
By using Gumming (JC) model. energy-level gap of this the pseudo invariant eigen-operator method we The pseudo-invariant eigen-operator is found in JC Hamiltonian is derived. This approach seems analyze the field-in... By using Gumming (JC) model. energy-level gap of this the pseudo invariant eigen-operator method we The pseudo-invariant eigen-operator is found in JC Hamiltonian is derived. This approach seems analyze the field-intensity-dependent Jaynes terms of the supersymmetric generators. The concise. 展开更多
关键词 pseudo-invariant eigen-operator energy-level gap Jaymes-Cummings model
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Researches of DC-Problem Under the Model S in which the Numbers of Defective Coins are not Fixed
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作者 丁承杰 刘文安 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第4期106-110,共5页
In this paper,we research general Defective Cion Problem under the model S,i.e,the number d of Defective cions is not fixed. For d=O,1,or 2. we get some good results.
关键词 model s test set optimal test scheme
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Traffic Forecasting Model Based on Takagi-Sugeno Fuzzy Logical System
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作者 王维工 李征 程美玲 《Journal of Donghua University(English Edition)》 EI CAS 2005年第1期129-132,共4页
The local multiple regression fuzzy(LMRF)model based on Takagi-Sugeno fuzzy logical system and its application in traffic forecasting is proposed. Besides its prediction accuracy is testified and the model is proved m... The local multiple regression fuzzy(LMRF)model based on Takagi-Sugeno fuzzy logical system and its application in traffic forecasting is proposed. Besides its prediction accuracy is testified and the model is proved much better than conventional forecasting methods. According to the regional traffic system, the model perfectly states the complex non-linear relation of the traffic and the local social economy. The model also efficiently deals with the system lack of enough data. 展开更多
关键词 T-s model traffic forecasting LMRF model.
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Geometric Phase in a Time-Dependent A-Type Jaynes-Cummings Model
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作者 QIN Xian-Ming YU Zbao-Xian +1 位作者 JIAO Zhi-Yong XIE Bing-Hao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第3期407-410,共4页
By using the Lewis-Riesenfeld invariant theory, we have studied the dynamical and the geometric phases in a generalized time-dependent A-type Jaynes Cummings model. We lind that, compared with the dynamical phases, th... By using the Lewis-Riesenfeld invariant theory, we have studied the dynamical and the geometric phases in a generalized time-dependent A-type Jaynes Cummings model. We lind that, compared with the dynamical phases, the geometric phases in a cycle case are independent of the frequency of the photon field, the coupling coefficient between photons and atoms, and the atom transition frequency. It is pointed out that the geometric phases in a cycle ease can be measured under the case of a stronger time-dependent photon field and a stronger coupling photon-atom system. On the other hand, the geometric phases of the model may be measured in the composition of cold atoms. 展开更多
关键词 geometric phase generalized Jaynes-Cummings model
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