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Novel Early-Warning Model for Customer Churn of Credit Card Based on GSAIBAS-Cat Boost
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作者 Yaling Xu Congjun Rao +1 位作者 Xinping Xiao Fuyan Hu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第12期2715-2742,共28页
As the banking industry gradually steps into the digital era of Bank 4.0,business competition is becoming increasingly fierce,and banks are also facing the problem of massive customer churn.To better maintain their cu... As the banking industry gradually steps into the digital era of Bank 4.0,business competition is becoming increasingly fierce,and banks are also facing the problem of massive customer churn.To better maintain their customer resources,it is crucial for banks to accurately predict customers with a tendency to churn.Aiming at the typical binary classification problem like customer churn,this paper establishes an early-warning model for credit card customer churn.That is a dual search algorithm named GSAIBAS by incorporating Golden Sine Algorithm(GSA)and an Improved Beetle Antennae Search(IBAS)is proposed to optimize the parameters of the CatBoost algorithm,which forms the GSAIBAS-CatBoost model.Especially,considering that the BAS algorithm has simple parameters and is easy to fall into local optimum,the Sigmoid nonlinear convergence factor and the lane flight equation are introduced to adjust the fixed step size of beetle.Then this improved BAS algorithm with variable step size is fused with the GSA to form a GSAIBAS algorithm which can achieve dual optimization.Moreover,an empirical analysis is made according to the data set of credit card customers from Analyttica official platform.The empirical results show that the values of Area Under Curve(AUC)and recall of the proposedmodel in this paper reach 96.15%and 95.56%,respectively,which are significantly better than the other 9 common machine learning models.Compared with several existing optimization algorithms,GSAIBAS algorithm has higher precision in the parameter optimization for CatBoost.Combined with two other customer churn data sets on Kaggle data platform,it is further verified that the model proposed in this paper is also valid and feasible. 展开更多
关键词 Customer churn early-warning model IBAS GSAIBAS-CatBoost
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China agricultural outlook for 2015–2024 based on China Agricultural Monitoring and Early-warning System(CAMES) 被引量:12
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作者 XU Shi-wei LI Gan-qiong LI Zhe-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第9期1889-1902,共14页
The primary goal of Chinese agricultural development is to guarantee national food security and supply of major agricultural products. Hence, the scientiifc work on agricultural monitoring and early warning as wel as ... The primary goal of Chinese agricultural development is to guarantee national food security and supply of major agricultural products. Hence, the scientiifc work on agricultural monitoring and early warning as wel as agricultural outlook must be strengthened. In this study, we develop the China Agricultural Monitoring and Early-warning System (CAMES) on the basis of a comparative study of domestic and international agricultural outlook models. The system is a dynamic and multi-market partial equilibrium model that integrates biological mechanisms with economic mechanisms. This system, which includes 11 categories of 953 kinds of agricultural products, could dynamical y project agricultural market supply and demand, assess food security, and conduct scenario analysis at different spatial levels, time scale levels, and macro-micro levels. Based on the CAMES, the production, consumption, and trade of the major agricultural products in China over the next decade are projected. The fol owing conclusions are drawn:i) The production of major agricultural products wil continue to grow steadily, mainly because of the increase in yield. i ) The growth of agricultural consumption wil be slightly higher than that of agricultural production. Meanwhile, a high self-sufifciency rate is expected for cereals such as rice, wheat, and maize, with the rate being stable at around 97%. i i) Agricultural trade wil continue to thrive. The growth of soybean and milk im-ports wil slow down, but the growth of traditional agricultural exports such as vegetables and fruits is expected to continue. 展开更多
关键词 agricultural outlook PROJECTION China Agricultural Monitoring and early-warning System(CAMES) agriculture of China
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Deformation early-warning index for heightened gravity dam during impoundment period 被引量:10
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作者 Bo Chen Zi-shen Huang +1 位作者 Teng-fei Bao Zheng Zhu 《Water Science and Engineering》 EI CAS CSCD 2021年第1期54-64,共11页
The mechanical parameters of materials in a dam body and dam foundation tend to change when dams are reinforced in aging processes.It is important to use an early-warning index to reflect the safety status of dams,par... The mechanical parameters of materials in a dam body and dam foundation tend to change when dams are reinforced in aging processes.It is important to use an early-warning index to reflect the safety status of dams,particularly of heightened projects in the impoundment period.Herein,a new method for monitoring the safety status of heightened dams is proposed based on the deformation monitoring data of a dam structure,a statistical model,and finite-element numerical simulation.First,a fast optimization inversion method for estimation of dam mechanical parameters was developed,which used the water pressure component extracted from a statistical model,an improved inversion objective function,and a genetic optimization iterative algorithm.Then,a finite element model of a heightened concrete gravity dam was established,and the deformation behavior of the dam with rising water levels in the impoundment period was simulated.Subsequently,mechanical parameters of aged dam parts were calculated using the fast optimization inversion method with simulated deformation and the water pressure deformation component obtained by the statistical model under the same conditions of water pressure change.Finally,a new earlywarning index of dam deformation was constructed by means of the forward-simulated deformation and other components of the statistical model.The early-warning index is useful for forecasting dam deformation under different water levels,especially high water levels. 展开更多
关键词 Concrete gravity dam Parameter inverse analysis Structural health monitoring early-warning index Finite element simulation
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A new early-warning prediction system for monitoring shear force of fault plane in the active fault 被引量:2
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作者 Manchao He Yu Wang Zhigang Tao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2010年第3期223-231,共9页
The most common method used to describe earthquake activity is based on the changes in physical parameters of the earth's surface such as displacement of active fault and seismic wave.However,such approach is not suc... The most common method used to describe earthquake activity is based on the changes in physical parameters of the earth's surface such as displacement of active fault and seismic wave.However,such approach is not successful in forecasting the movement behaviors of faults.In the present study,a new mechanical model of fault activity,considering the shear strength on the fault plane and the influence of the resistance force,is established based on the occurrence condition of earthquake.A remote real-time monitoring system is correspondingly developed to obtain the changes in mechanical components within fault.Taking into consideration the local geological conditions and the history of fault activity in Zhangjiakou of China,an active fault exposed in the region of Zhangjiakou is selected to be directly monitored by the real-time monitoring technique.A thorough investigation on local fault structures results in the selection of two suitable sites for monitoring potential active tectonic movements of Zhangjiakou fault.Two monitoring curves of shear strength,recorded during a monitoring period of 6 months,turn out to be steady,which indicates that the potential seismic activities hardly occur in the adjacent region in the near future.This monitoring technique can be used for early-warning prediction of the movement of active fault,and can help to further gain an insight into the interaction between fault activity and relevant mechanisms. 展开更多
关键词 active faults monitoring EARTHQUAKE early-warning system shear strength
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Risk Early-Warning Method for Natural Disasters Based on Integration of Entropy and DEA Model 被引量:4
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作者 Fengshan Wang Yan Cao Meng Liu 《Applied Mathematics》 2011年第1期23-32,共10页
Risk early-warning of natural disasters is a very intricate non-deterministic prediction, and it was difficult to resolve the conflicts and incompatibility of the risk structure. Risk early-warning factors of natural ... Risk early-warning of natural disasters is a very intricate non-deterministic prediction, and it was difficult to resolve the conflicts and incompatibility of the risk structure. Risk early-warning factors of natural disasters were differentiated into essential attributes and external characters, and its workflow mode was established on risk early-warning structure with integrated Entropy and DEA model, whose steps were put forward. On the basis of standard risk early-warning DEA model of natural disasters, weight coefficient of risk early-warning factors was determined with Information Entropy method, which improved standard risk early-warning DEA model with non-Archimedean infinitesimal, and established risk early-warning preference DEA model based on integrated entropy weight and DEA Model. Finally, model was applied into landslide risk early-warning case in earthquake-damaged emergency process on slope engineering, which exemplified the outcome could reflect more risk information than the method of standard DEA model, and reflected the rationality, feasibility, and impersonality, revealing its better ability on comprehensive safety and structure risk. 展开更多
关键词 ENTROPY Data Envelopment Analysis Comprehensive INTEGRATION ESSENTIAL ATTRIBUTE Risk early-warning Natural DISASTER
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The Innovation Research of Financial Early-Warning Index Measurement 被引量:3
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作者 Zhang You-tang Cheng Jun-ning Liang Wei-jun 《Wuhan University Journal of Natural Sciences》 CAS 2002年第3期281-284,共4页
The period economic fluctuation is vital for an enterprise to exist and further develop, it directly affect the enterprise financial health. So, it is significant to build up financial early-warning index and measure ... The period economic fluctuation is vital for an enterprise to exist and further develop, it directly affect the enterprise financial health. So, it is significant to build up financial early-warning index and measure the warning condition that the enterprise faces and take the effective measures to eliminate. We criticize Altman’sZ calculating model and build up some new indexes for enterprise financial early-warning condition measuring and making sound decision. 展开更多
关键词 financial early-warning index critical value cash earning value cash added value
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Early-warning signals for an outbreak of the influenza pandemic 被引量:2
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作者 任迪 高洁 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第12期461-464,共4页
Over the course of human history, influenza pandemics have been seen as major disasters, so studies on the influenza virus have become an important issue for many experts and scholars. Comprehensive research has been ... Over the course of human history, influenza pandemics have been seen as major disasters, so studies on the influenza virus have become an important issue for many experts and scholars. Comprehensive research has been performed over the years on the biological properties, chemical characteristics, external environmental factors and other aspects of the virus, and some results have been achieved. Based on the chaos game representation walk model, this paper uses the time series analysis method to study the DNA sequences of the influenza virus from 1913 to 2010, and works out the early-warning signals indicator value for the outbreak of an influenza pandemic. The variances in the CCR wall〈 sequences for the pandemic years (or + -1 to 2 years) are significantly higher than those for the adjacent years, while those in the non-pandemic years are usually smaller. In this way we can provide an influenza early-warning mechanism so that people can take precautions and be well prepared prior to a pandemic. 展开更多
关键词 influenza virus early-warning signals chaos game representation (CGR) walk model DNA sequence
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A study on the early-warning technique concerning debris flow disasters 被引量:1
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作者 ZHOU Jinxing, WANG Lixian, XIE Baoyuan, FEI Shimin, WANG Xilin (1. Inst. of Forestry Research, Chinese Academy of Forestry Science, Beijing 100091, China 2. College of Resource & Environment, Beijing Forestry University, Beijing 100083, China) 《Journal of Geographical Sciences》 SCIE CSCD 2002年第3期363-370,共8页
According to the principle of the eruption of debris flows, the new torrent classification techniques are brought forward. The torrent there can be divided into 4 types such as the debris flow torrent with high destru... According to the principle of the eruption of debris flows, the new torrent classification techniques are brought forward. The torrent there can be divided into 4 types such as the debris flow torrent with high destructive strength, the debris flow torrent, high sand-carrying capacity flush flood torrent and common flush flood by the techniques. In this paper, the classification indices system and the quantitative rating methods are presented. Based on torrent classification, debris flow torrent hazard zone mapping techniques by which the debris flow disaster early-warning object can be ascertained accurately are identified. The key techniques of building the debris flow disaster neural network (NN) real time forecasting model are given detailed explanations in this paper, including the determination of neural node at the input layer, the output layer and the implicit layer, the construction of knowledge source and the initial weight value and so on. With this technique, the debris flow disaster real-time forecasting neural network model is built according to the rainfall features of the historical debris flow disasters, which includes multiple rain factors such as rainfall of the disaster day, the rainfall of 15 days before the disaster day, the maximal rate of rainfall in one hour and ten minutes. It can forecast the probability, critical rainfall of eruption of the debris flows, through the real-time rainfall monitoring or weather forecasting. Based on the torrent classification and hazard zone mapping, combined with rainfall monitoring in the rainy season and real-time forecasting models, the debris flow disaster early-warning system is built. In this system, the GIS technique, the advanced international software and hardware are applied, which makes the system’s performance steady with good expansibility. The system is a visual information system that serves management and decision-making, which can facilitate timely inspect of the variation of the torrent type and hazardous zone, the torrent management, the early-warning of disasters and the disaster reduction and prevention. 展开更多
关键词 debris flows disaster early-warning technique torrent classification mapping of the hazard zones
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The Management Platform for Online Rate of Meteorological Early-warning Loudspeakers 被引量:1
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作者 Bing SHAO Baolei DONG Jifeng SONG 《Asian Agricultural Research》 2017年第2期57-58,共2页
The meteorological early-warning loudspeaker is a specific initiative for the meteorological departments to address the issues concerning issues concerning agriculture,countryside and farmers.Its significance is that ... The meteorological early-warning loudspeaker is a specific initiative for the meteorological departments to address the issues concerning issues concerning agriculture,countryside and farmers.Its significance is that it can promptly deliver the early-warning information concerning some meteorological disasters(such as torrential rains,typhoons,cold wave,hail)to the areas affected,so as to provide reference and protection for agricultural production and effectively reduce the loss of agricultural producers.Up to now,the meteorological early-warning loudspeakers in Benxi have covered the villages.However,due to irregular occurrence of meteorological disasters,the listeners will turn off the information receivers of meteorological early-warning loudspeakers when they fail to receive meteorological information for a long time,so that the users can not promptly know the early-warning information regarding some sudden meteorological disasters.In view of this,the meteorological departments have introduced a series of management measures,such as the daily use of loudspeakers to publish weather forecast information,aimed at improving the online rate and usage rate of meteorological loudspeakers.And the management platform for online rate of meteorological early-warning loudspeakers is an important part of the management system. 展开更多
关键词 Meteorological early-warning loudspeakers Weather LAN Storing process SMS
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Research on Technology Early-Warning System Based on Dynamic Information Monitoring
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作者 汪雪锋 朱东华 +1 位作者 刘嵩 刘佳 《Journal of Beijing Institute of Technology》 EI CAS 2009年第1期121-126,共6页
Relying on the advanced information technologies, such as information monitoring, data mining, natural language processing etc., the dynamic technology early-warning system is constructed. The system consists of techn... Relying on the advanced information technologies, such as information monitoring, data mining, natural language processing etc., the dynamic technology early-warning system is constructed. The system consists of technology information automatic retrieval, technology information monitoring, technology threat evaluation, and crisis response and management subsystem, which implements uninterrupted dynamic monitoring, trace and crisis early-warning to the specific technology. Empirical study testifies that the system improves the accuracy, timeliness and reliability of technology early-warning. 展开更多
关键词 technology early-warning system information monitoring dynamic retrieval technology threatevaluation crisis response and management
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Financial crisis early-warning model of listed companies based on predicted value
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作者 Liu Yanwen Zhao Chunyang(School of Management, Dalian University of Technology, Dalian 116024, China) 《Journal of Southeast University(English Edition)》 EI CAS 2008年第S1期160-163,共4页
To establish a financial early-warning model with high accuracy of discrimination and achieve the aim of long-term prediction, principal component analysis (PCA), Fisher discriminant, together with grey forecasting mo... To establish a financial early-warning model with high accuracy of discrimination and achieve the aim of long-term prediction, principal component analysis (PCA), Fisher discriminant, together with grey forecasting models are used at the same time. 110 A-share companies listed on the Shanghai and Shenzhen stock exchange are selected as research samples. And 10 extractive factors with 89.746% of all the original information are determined by applying PCA, which obtains the goal of dimension reduction without information loss. Based on the index system, the early-warning model is constructed according to the Fisher rules. And then the GM(1,1) is adopted to predict financial ratios in 2004, according to 40 testing samples from 2000 to 2003. Finally, two different methods, a self-validated and a forecasting-validated, are used to test the validity of the financial crisis warning model. The empirical results show that the model has better predictability and feasibility, and GM(1,1) contributes to the ability to make long-term predictions. 展开更多
关键词 financial crisis early-warning Fisher discriminant GM(1 1) model
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"Consumption and Enviromment" Early-warning Mechanism for Export of Autos Will Be Improved in China
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《China Standardization》 2006年第2期1-,共1页
关键词 Consumption and Enviromment early-warning Mechanism for Export of Autos Will Be Improved in China BE
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Studies on Early-warning System for Social Stability: Vital to China
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《Bulletin of the Chinese Academy of Sciences》 2000年第4期197-197,共1页
As a large country in the world, it is both necessary and possible to develop and operate a pre-warning system for social stability, says Prof. Niu Wenyuan, chief scientist for strate-
关键词 Studies on early-warning System for Social Stability Vital to China
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Key technologies of earthquake early warning system for China’s high-speed railway
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作者 Geming Zhang Lin Yang Wenxiang Jiang 《Railway Sciences》 2024年第2期239-262,共24页
Purpose–The purpose of this study is to introduce the top-level design ideas and the overall architecture of earthquake early-warning system for high speed railways in China,which is based on P-wave earthquake early-... Purpose–The purpose of this study is to introduce the top-level design ideas and the overall architecture of earthquake early-warning system for high speed railways in China,which is based on P-wave earthquake early-warning and multiple ways of rapid treatment.Design/methodology/approach–The paper describes the key technologies that are involved in the development of the system,such as P-wave identification and earthquake early-warning,multi-source seismic information fusion and earthquake emergency treatment technologies.The paper also presents the test results of the system,which show that it has complete functions and its major performance indicators meet the design requirements.Findings–The study demonstrates that the high speed railways earthquake early-warning system serves as an important technical tool for high speed railways to cope with the threat of earthquake to the operation safety.The key technical indicators of the system have excellent performance:The first report time of the P-wave is less than three seconds.From the first arrival of P-wave to the beginning of train braking,the total delay of onboard emergency treatment is 3.63 seconds under 95%probability.The average total delay for power failures triggered by substations is 3.3 seconds.Originality/value–The paper provides a valuable reference for the research and development of earthquake early-warning system for high speed railways in other countries and regions.It also contributes to the earthquake prevention and disaster reduction efforts. 展开更多
关键词 Earthquake early-warning High speed railway China earthquake networks center(CENC) Earthquake emergency treatment
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Realization of Toffoli gate operation using four-level atoms in cavity QED system 被引量:2
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作者 唐世清 张登玉 +2 位作者 谢利军 詹孝贵 高峰 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第1期56-61,共6页
This paper proposes a scheme for realization of a three-qubit Toffoli gate operation using three four-level atoms by a selective atom-field interaction in a cavity quantum electrodynamics system. In the proposed proto... This paper proposes a scheme for realization of a three-qubit Toffoli gate operation using three four-level atoms by a selective atom-field interaction in a cavity quantum electrodynamics system. In the proposed protocol, the quantum information is encoded on the stable ground states of atoms, and atomic spontaneous emission is negligible as the large atom-avity detuning effectively suppresses the spontaneous decay of the atoms. The influence of the dissipation on fidelity and success probability of the three-qubit Toffoli gate is also discussed. The scheme can also be applied to realize an N-qubit Toffoli gate and the interaction time required does not rise with increasing the number of qubits. 展开更多
关键词 Toffoli gate four-level atom cavity QED FIDELITY
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Influence of Doppler broadening and spontaneously generated coherence on propagation effect in a quasi lambda-type four-level system 被引量:1
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作者 刘中波 梁颖 +1 位作者 贾克宁 樊锡君 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第2期322-332,共11页
In this paper we study influences of Doppler broadening, spontaneously generated coherence, and other system parameters on propagation effect in a quasi lambda-type four-level atomic system. It is shown that when the ... In this paper we study influences of Doppler broadening, spontaneously generated coherence, and other system parameters on propagation effect in a quasi lambda-type four-level atomic system. It is shown that when the Doppler broadening is present, generally speaking, the values of gain and intensity of lasing without inversion (i.e. the probe field) in the co-propagating probe and driving fields case are much larger than those in the counter-propagating case; considerably larger gain and intensity of lasing without inversion than those without the Doppler broadening can be obtained by choosing appropriate values of the Doppler broadening width and spontaneously generated coherence strength. The gain and intensity of lasing without inversion increase with the increase of spontaneously generated coherence strength; when spontaneously generated coherence is present, much larger gain and intensity of lasing without inversion than those in the case without spontaneously generated coherence can be obtained. Choosing suitable values of the probe detuning, Rabi frequencies of the driving and pump fields at the entrance of the medium also can remarkably enhance the gain and intensity of lasing without inversion. 展开更多
关键词 four-level system propagation effect spontaneously generated coherence Doppler broadening lasing without inversion
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Phase grating in a doubly degenerate four-level system
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作者 刘云 王朴 彭双艳 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期287-291,共5页
In this paper, we suggest a doubly degenerate four-level system, in which the transition takes place between the hyperfine energy 52S1/2 F = 1 and 52P3/2 F = 2 in rubidium 87 D2 line, for studying atomic phase grating... In this paper, we suggest a doubly degenerate four-level system, in which the transition takes place between the hyperfine energy 52S1/2 F = 1 and 52P3/2 F = 2 in rubidium 87 D2 line, for studying atomic phase grating based on the cross-Kerr and phase conjugation effects. The phase grating with high efficiency can be obtained by tuning phase shift Ф between the coupling and probe field, when the coupling intensity is much stronger than the strength of probe field. Under different coupling intensities, a high diffraction efficiency can be maintained. A new and simple way of implementing phase grating is presented. However, in such an atomic system, two main limitations must be taken into account. First, the independence between steady state probe susceptibility and the coupling intensity, when the population decay rate is larger than the Rabi frequency of the coupling field, cannot result in diffraction grating; second, the sample to be prepared should not be too long. 展开更多
关键词 phase grating quantum interference four-level system STANDING-WAVE
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Fluorescence properties in a single driven four-level atomic system
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作者 姜向前 吕志伟 +1 位作者 张冰 孙秀冬 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第11期270-274,共5页
The spontaneous emission decay dynamics of a tripod configuration four-level atom driven by a single laser field is studied. Under different initial conditions, we discuss the effects of quantum interference and detun... The spontaneous emission decay dynamics of a tripod configuration four-level atom driven by a single laser field is studied. Under different initial conditions, we discuss the effects of quantum interference and detuning of external driving field on atomic spontaneous emission properties. For the larger detuning, the interesting phenomena of the spectral line narrowing are found which stem from the contribution of external driving field. 展开更多
关键词 spontaneous emission spectrum four-level atom driving field
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Lasing without inversion in a four-level diamond system
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作者 高强 宋同强 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第12期243-249,共7页
We study the lasing without inversion in a four-level diamond configuration in the case of incoherent pumping field within the framework of the bare-state basis. With the strong fields limit, we obtain the approximate... We study the lasing without inversion in a four-level diamond configuration in the case of incoherent pumping field within the framework of the bare-state basis. With the strong fields limit, we obtain the approximate steady-state solution, and discuss the dependence of population distribution and system gain on probe detuning and auxiliary field Rabi frequency. 展开更多
关键词 lasing without inversion four-level diamond system cyclic transition
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Four-level model of ion-ion laser-induced collisional energy transfer and numerical calculations for Ca^+-Sr^+ system
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作者 陈德应 张洪英 樊荣伟 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期233-240,共8页
The four-level model of laser-induced collisional energy transfer (LICET) for the ion-ion collision system is established based on the time-dependent SchrSdinger equation for the electron dynamics, through which the... The four-level model of laser-induced collisional energy transfer (LICET) for the ion-ion collision system is established based on the time-dependent SchrSdinger equation for the electron dynamics, through which the equations of motion of the probability amplitudes and cross section of the collision system are obtained. Numerical calculations are performed for the Ca+ Sr+ system, with the results showing that the peak of the LICET spectrum appears at a resonant frequency of the transfer laser. The magnitude of the obtained collision cross section is in the order of 10-16 cm2, and is comparable to that obtained in atomic systems, which indicates the validity of the established four-level model. 展开更多
关键词 laser-induced collisional energy transfer four-level model Ca+-Sr+ system
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