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Continuous Variable Entanglement and Violation of Bell Inequality for Two Modes in a three-level Cascade Atomic System

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Chinese Physics Letters 2007年第3期24卷 609-612页

作者：平云霞成泽 Department of Physics Huazhong University of Science and Technology Wuhan 430074

Continuous variable entanglement and violation of Bell inequality for two modes are investigated in a three-level cascade atomic system. Entanglement of the system is demonstrated according to the entanglement criterion [Phys. Rev. Lett. 84 （2000）2722]. Violation of Bell inequality is studied within the framework of a quantum theory of multiwave mixing. It is shown that there are some states that are entangled but do not violate the Bell inequality.

关键词： Entanglement Inequality three-level

Impedance Modeling and Stability Analysis of a three-phase three-level NPC Inverter Connected to the Grid

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CSEE Journal of Power and Energy Systems 2020年第2期6卷 270-278页

作者： Bo Zhang Xiong Du Jingbo Zhao Jiapei Zhou Xiaoming Zou State Key Laboratory of Power Transmission Equipment&System Security and New Technology(Chongqing University) Shapingba DistrictChongqing 400044China Power System Technology Center Electric Power Research Institute of State GridJiangsu Electric Power Co.Ltd.Jiangsu 320115China HVDC Simulation Center Department of HVDC technologyGlobal Energy Interconnection Research InstituteBeijing 102209China

The interaction between grid-connected inverters and the grid may cause stability issues,and compromise the reliable operation of the inverters.This study investigates the stability of a three-level neutral point clamped(NPC)inverter connected to the grid using impedance-based methods.Because the impedance model of a three-phase three-level NPC inverter has not yet been reported,this study fills the literature gap by analyzing the influence of three-level DC-side neutral point control on the impedance characteristics.By fully considering the DC bus dynamics and DC voltage control loop,and the current loop and phase-locked loop(PLL),the admittance model of a three-phase three-level NPC inverter is established and verified by simulation.Additionally,in the stability analysis of a threelevel NPC inverter grid-connected system,the frequency coupling introduced by the PLL and DC bus dynamics is included with the help of an established admittance model.The stability of the grid-connected system under different grid short circuit ratios(SCR)and operating power levels is analyzed according to the Nyquist stability criterion.The experimental results revealed that the established impedance model of the three-phase three-level NPC inverter can properly represent the stability of this system.

关键词： Grid-connected inverter neutral point control stability three-level

A three-level authenticated conference key establishment protocol for UMTS networks

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第5期12卷 371-378页

作者： Chung-Fu LU Tzong-Chen WU Chien-Lung HSU Department of Information Management National Taiwan University of Science and Technology Department of Computer and Communication Engineering Taipei College of Maritime Technology Department of Information Management Chang Gung University

A conference key establishment protocol allows a group of conferees to agree on a secret key shared among them for secure group communication.This paper proposes a three-level conference key establishment protocol based on the Universal Mobile Telecommunications System (UMTS) framework to establish a group-level key,home location register (HLR) level keys,and visitor location register (VLR) level keys simultaneously for a group of conferees.The group-level key is used to secure the communications for all conferees,the HLR-level key is for those within the same HLR domain,and the VLR-level key is for those within the same VLR domain.The group-level key can be used for securing inter-domain group-oriented applications such as commercial remote conferencing systems.The HLRand VLR-level keys can be used for securing intra-domain subgroup applications (e.g.,location-based or context-aware services) and dynamic key updating.Since our proposed protocol exploits existing UMTS security functions and the exclusive-or operation,it is compatible with UMTS architecture.This means that it is fast and easy to implement on the existing UMTS architecture.Furthermore,the proposed protocol has low computational complexities and can provide cost effectiveness,load-amortization,scalability,user authentication,key establishment,key confirmation,key updating,and lawful interception.

关键词： Universal Mobile Telecommunications System (UMTS) three-level Conference key establishment Secure group communication Authentication

Teleporting N-qubit unknown atomic state by utilizing the V-type three-level atom

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Science China(Physics,Mechanics & Astronomy) 2009年第7期52卷 1034-1038页

作者： ZHANG XinHua YANG ZhiYong XU PeiPei School of Technical Physics Xidian UniversityXi’an 710071China School of Electronic Engineering Xidian UniversityXi’an 710071China

Realizing the teleportation of quantum state, especially the teleportation of N-qubit quantum state, is of great importance in quantum information. In this paper, Raman-interaction of the V-type degenerate three-level atom and single-mode cavity field is studied by utilizing complete quantum theory. Then a new scheme for teleporting N-qubit unknown atomic state via Raman-interaction of the V-type degenerate three-level atom with a single-mode cavity field is proposed, which is based upon the complete quantum theory mentioned above.

关键词： quantum optics quantum informatics raman-interaction quantum teleportation V-type degenerate three-level atom contrary state of coherent state quantum entanglement

Inversionless amplification of a monochromatic field in a nonresonant three-level ∧ medium

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Chinese Science Bulletin 1995年第1期40卷 84-86页

作者：龚尚庆徐至展 Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China

A three-level medium is the simplest and most suitable model for understanding the physical mechanisras of amplification without inversion (AWI). Various analyses were presented for all possible resonant three-level configurations. Recently, P. Mandel et al. have studied the AWI in three-level ∧ model for general nonresonant case and obtained the condition for establishing AWl. In our note the inversionless amplification of a monochromatic field in a nonresonant three-level ∧ medium will be investigated.

关键词： inversionless amplification three-level ^ medium nouresouance.

Entropy squeezing for three-level atom interacting with a single-mode field

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Chinese Physics B 2019年第6期28卷 81-86页

作者：刘非凡方卯发许雄 Synergetic Innovation Center for Quantum Effects and Application Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of EducationSchool of Physics and ElectronicsHunan Normal UniversityChangsha 410081China

The entropy squeezing for a three-level atom interacting with a single-model field is studied. A general definition of entropy squeezing for three-level atom is given according to entropic uncertainty relation of three-level system, and the calculation formalism of entropy is derived for a cascade three-level atom. By using numerical calculation, the entropy squeezing properties of a cascade three-level atom are examined. Our results show that, three-level atom can generate obvious entropy squeezing effect via choosing appropriate superposition state of three-level atom. Our results are meaningful for preparing three-level system information resources with ultra-low quantum noise.

关键词： variance squeezing entropy squeezing three-level atom

A Space Vector Modulation Based three-level PWM Rectifier under Simple Sliding Mode Control Strategy

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Energy and Power Engineering 2013年第3期5卷 28-35页

作者： Azeddine Draou Senior Mieee Department of Electrical Engineering University of Hail Hail Kingdom of Saudi Arabia

In this paper, a voltage oriented control strategy for three-level PWM rectifier based on Sliding Mode Control (SMC) is introduced in order to obtain fast and accurate response of dc-bus voltage. To verify the validity of the analysis and the feasibility of the proposed control method a set of simulation tests have been conducted using Matlab/Simulink. The simulation results show that compared to the conventional PI controller, the SMC can reduce drastically the three-level rectifier’s voltage fluctuation and improve the dynamic response of dc-bus significantly.

关键词： three-level PWM Rectifier Voltage Oriented Control Sliding Mode Control Unbalanced Input Voltage

Multilevel Modeling of Binary Outcomes with three-level Complex Health Survey Data

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Open Journal of Epidemiology 2017年第1期7卷 27-43页

作者： Shafquat Rozi Sadia Mahmud Gillian Lancaster Wilbur Hadden Gregory Pappas Department of Mathematics and Statistics Lancaster University Lancashire UK Department of Community Health Sciences Aga Khan University Karachi Pakistan Department of Medicine Visiting Faculty Aga Khan University Karachi Pakistan Department of Sociology University of Maryland College Park USA George Washington University District of Columbia Washington DC USA

Complex survey designs often involve unequal selection probabilities of clus-ters or units within clusters. When estimating models for complex survey data, scaled weights are incorporated into the likelihood, producing a pseudo likeli-hood. In a 3-level weighted analysis for a binary outcome, we implemented two methods for scaling the sampling weights in the National Health Survey of Pa-kistan (NHSP). For NHSP with health care utilization as a binary outcome we found age, gender, household (HH) goods, urban/rural status, community de-velopment index, province and marital status as significant predictors of health care utilization (p-value level, and 0.2726 (standard error 0.0995) for household level respectively. Both esti-mates are significantly different from zero (p-value three analyses, weighted (two scaling methods) and un-weighted, converged to almost identical results with few exceptions. This may have occurred because of the large num-ber of 3rd and 2nd level clusters and relatively small ICC. We performed a sim-ulation study to assess the effect of varying prevalence and intra-class correla-tion coefficients (ICCs) on bias of fixed effect parameters and variance components of a multilevel pseudo maximum likelihood (weighted) analysis. The simulation results showed that the performance of the scaled weighted estimators is satisfactory for both scaling methods. Incorporating simulation into the analysis of complex multilevel surveys allows the integrity of the results to be tested and is recommended as good practice.

关键词： Health Care Utilization Complex Health Survey with Sampling Weights Simulations for Complex Survey Pseudo Likelihood three-level Data

Resonant Fluorescence of a Λ-type Degenerate Quantum-beat three-level Atom

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Chinese Journal of Lasers 1998年第3期 94-97页

ＲｅｓｏｎａｎｔＦｌｕｏｒｅｓｃｅｎｃｅｏｆａΛｔｙｐｅＤｅｇｅｎｅｒａｔｅＱｕａｎｔｕｍｂｅａｔＴｈｒｅｌｅｖｅｌＡｔｏｍＣＡＯＺｈｕｏｌｉａｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＰｈｙｓｉｃｓ，ＡｎｈｕｉＵｎｉｖｅ... 详细信息

ＲｅｓｏｎａｎｔＦｌｕｏｒｅｓｃｅｎｃｅｏｆａΛｔｙｐｅＤｅｇｅｎｅｒａｔｅＱｕａｎｔｕｍｂｅａｔＴｈｒｅｌｅｖｅｌＡｔｏｍＣＡＯＺｈｕｏｌｉａｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＰｈｙｓｉｃｓ，ＡｎｈｕｉＵｎｉｖｅｒｓｉｔｙ，Ｈｅｆｅｉ２３００３９...

关键词： Atom three-level type Fluorescence Quantum-beat Resonant Degenerate