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Chinese Physics Letters 2014年第9期31卷 48-51页

作者：庄伟张同刚陈景标 Institute of Quantum Electronics and State Key Laboratory of Advanced Optical Communication System and Network School of Electronics Engineering and Computer Science Peking University Beijing 100871

We propose a scheme for an active ion optical clock with a detailed description of the pumping method, lasing states, output power, linewidth and light shift. Considering 171 yb＋ ions in a Paul trap, we propose utilizing a Fabry-Perot resonator to realize the lasing of active optical frequency standards. The quantum-limited linewidth of an active 171 yb＋ ion optical clock is narrower than I mHz. Based on the mechanism and the advantages of an active optical clock at the ion optical clock transition frequency, this new laser light source as a stable local oscillator will be beneficial to the single-ion optical clock, which currently is one of the most accurate clocks.

关键词： ACTIVE medium FABRY-Perot resonators OPTICAL frequency conversion RESEARCH IONS QUANTUM mechanics

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Comprehensive-Forecast Multiobjective Genetic Programming for Neural Architecture Search

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IEEE Transactions on Evolutionary Computation 2025年

作者： Cao, Bin Luo, Xiao Liu, Xin Li, Yun Hebei University of Technology State Key Laboratory of Intelligent Power Distribution Equipment and System Tianjin 300401 China Hebei University of Technology School of Artificial Intelligence Tianjin 300401 China Hebei University of Technology School of Economics and Management Tianjin 300401 China University of Electronic Science and Technology of China Industrial Artificial Intelligence Centre Shenzhen Institute for Advanced Study Guangdong Shenzhen 518110 China

Neural Architecture Search (NAS) requires global topological exploration and is hence time consuming. To address this challenge, we propose the comprehensive-forecast multiobjective genetic programming for NAS, or CFMOGP-NAS for short. By integrating the strengths of various regression models and synthesizing the forecast of multiple candidates, the accuracy and robustness of architecture predictions are enhanced. The resultant algorithm this way incorporates a strategy of a mixture of complete and partial training, which balances cost and accuracy of evaluation. To also balance the population diversity, we develop a regularized tournament scheme for genetic programming. Experimental studies show that CFMOGP-NAS achieves a 50% reduction in search time without sacrificing accuracy, and verify that it substantially improves efficacy and efficiency compared with the state-of-the-art NAS methods. © 1997-2012 IEEE.

关键词： evaluation strategies Genetic programming multiobjective optimization neural architecture search

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Performance analysis of optical burst switching node with limited wavelength conversion capabilities

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Journal of Central South University 2009年第5期16卷 794-801页

作者：许毅史开源范戈 State Key Laboratory of Advanced Optical Communication System and Network Shanghai Jiao Tong University Weapon and Task System Research Office 92728 Army of the Chinese People's Liberation Army

The systematical and scalable frameworks were provided for estimating the blocking probabilities under asynchronous traffic in optical burst switching(OBS) nodes with limited wavelength conversion capability(LWCC) . The relevant system architectures of limited range and limited number of wavelength converters(WCs) deployed by a share-per-fiber(SPF) mode were developed,and the novel theoretical analysis of node blocking probability was derived by combining the calculation of discouraged arrival rate in a birth-death process and two-dimensional Markov chain model of SPF. The simulation results on single node performance verify the accuracy and effectiveness of the analysis models. Under most scenarios,it is difficult to distinguish the plots generated by the analysis and simulation. As the conversion degree increases,the accuracy of the analysis model worsens slightly. However,the utmost error on burst loss probability is far less than one order of magnitude and hence,still allows for an accurate estimate. Some results are of actual significance to the construction of next-generation commercial OBS backbones.

关键词： optical burst switching （OBS） limited range wavelength conversion （LRWC） wavelength converter burst contention burst loss probability

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Global evolution of an analyzer angle on the Faraday anomalous dispersion optical filter at 1529 nm

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Chinese Science Bulletin 2013年第36期58卷 4582-4587页

作者： TAO ZhiMing WANG YanFei HONG YeLong WANG DongYing ZHUANG Wei CHEN JingBiao State Key Laboratory of Advanced Optical Communication System and Network Institute of Quantum Electronics School of ElectronicsEngineering and Computer Science Peking University Department of Physics Bijie University

In order to realize laser frequency stabilization,the global evolution of an analyzer angle on the electrodeless-discharge-vaporlamp-based excited-state Faraday anomalous dispersion optical filter(LESFADOF)with a single transmission peak operating on the Rb1529 nm(5P3/2-4D5/2)is *** find that the transmission of the line center peak at 80°arrives at 14%in a 3 cm length lamp contained natural Rb mixed with 2 torr Xe buffer gas operating at 250°C with 176 MHz radio *** it is used to realize laser frequency stabilization,the LESFADOF at near 80°is *** a single transmission peak or double transmission peaks depend on the rf voltage when two polarizers are crossed.

关键词：法拉第反常色散光学滤波器演进激光稳频无电极放电无线电频率频率稳定激发态

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Electrical properties of zinc-oxide-based thin-film transistors using strontium-oxide-doped semiconductors

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Chinese Physics B 2015年第10期24卷 599-603页

作者：吴绍航张楠胡永生陈红蒋大鹏刘星元 State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanicsand PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory of Optical System Advanced Manufacturing Technology Chinese Academy of Sciences

Strontium-zinc-oxide（SrZnO） films forming the semiconductor layers of thin-film transistors（TFTs） are deposited by using ion-assisted electron beam evaporation. Using strontium-oxide-doped semiconductors, the off-state current can be dramatically reduced by three orders of magnitude. This dramatic improvement is attributed to the incorporation of strontium, which suppresses carrier generation, thereby improving the TFT. Additionally, the presence of strontium inhibits the formation of zinc oxide（ZnO） with the hexagonal wurtzite phase and permits the formation of an unusual phase of ZnO, thus significantly changing the surface morphology of ZnO and effectively reducing the trap density of the channel.

关键词： thin-film transistor ZnO electron beam evaporation

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Distribution of populations in excited states of electrodeless discharge lamp of Rb atoms

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Chinese Science Bulletin 2013年第16期58卷 1876-1881页

作者： TAO ZhiMing WANG YanFei HONG YeLong WANG DongYing ZHANG ShengNan ZHUANG Wei CHEN JingBiao State Key Laboratory of Advanced Optical Communication System and Network Institute of Quantum Electronics School of Electronics Engineering & Computer Science Peking University Department of Physics Bijie University

The intensity of fluorescence spectral lines of Rb atoms in the region of 350-1110nm is measured in eletrodeless discharge lamp. The population ratio between the excited states is calculated according to the spontaneous transition probabilities with rate equations. At the same time, the population density of energy level is also obtained. The results provide the potential applications of electrodeless discharge lamp in atomic filter and optical frequency reference at higher excited states without a pumping laser.

关键词：原子激发态无极灯铷原子种群分布人口密度无极放电灯原子滤光器概率计算

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Enhanced Privacy-Preserving WiFi Fingerprint Localization from CL Encryption

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Chinese Journal of Electronics 2024年第6期33卷 1435-1446页

作者： Zhiwei WANG Qiuchi ZHU Zhenqi ZHANG School of Computer Nanjing University of Posts and Telecommunications State Key Laboratory of Public Big Data Guizhou University Advanced Cryptography and System Security Key Laboratory of Sichuan Province Chengdu University of Information Engineering Key Laboratory of Computational Science and Application of Hainan Province Hainan Normal University

The WiFi fingerprint-based localization method is considered one of the most popular techniques for indoor localization. In INFOCOM'14, Li et al. proposed a wireless fidelity(WiFi) fingerprint localization system based on Paillier encryption, which is claimed to protect both client C 's location privacy and service provider S's database privacy. However, Yang et al. presented a practical data privacy attack in INFOCOM'18, which allows a polynomial time attacker to obtain S's database. We propose a novel WiFi fingerprint localization system based on CastagnosLaguillaumie(CL) encryption, which has a trustless setup and is efficient due to the excellent properties of CL encryption. To prevent Yang et al.'s attack, the system requires that S selects only the locations from its database that can receive the nonzero signals from all the available access points in C 's nonzero fingerprint in order to determine C's location. Security analysis shows that our scheme is secure under Li et al.'s threat model. Furthermore, to enhance the security level of privacy-preserving WiFi fingerprint localization scheme based on CL encryption, we propose a secure and efficient zero-knowledge proof protocol for the discrete logarithm relations in C's encrypted localization queries.

关键词： Location awareness Threat modeling Data privacy Protocols Databases Fingerprint recognition Trustless services Encryption Servers Wireless fidelity

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Thermal management for thermoset automated fiber placement based on infrared heater structure arrangement

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Chinese Journal of Aeronautics 2022年第1期35卷 173-183页

作者： Han WANG Weiwei WANG Haijin WANG Huiyue DONG Yinglin KE A State Key Laboratory of Fluid Power and Mechatronic System School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China Key Laboratory of Advanced Manufacturing Technology of Zhejiang Province School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China

Layup temperature is a vital factor that affects the production quality of automated fiber placement for thermoset *** high quality production,this paper proposes a new prediction model of layup temperature by considering the structure of infrared heater of automatic fiber placement *** model was first verified by comparing with the temperature results of layup *** a prediction on the effects of heater structure arrangement on layup temperature was conducted in the *** research shows that the length of infrared tube and the radian of reflective-film have significant influences,rather than other *** to this investigation,a heater structure-based heating strategy was presented in the paper to efficiently achieve constant temperature control in variable speed layup process.

关键词： Automated fiber placement Heating strategy optimization Infrared heater structure Thermal management Variable speed

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Quantum Phase Transition of the Bosonic Atoms near the Feshbach Resonance in an Optical Lattice

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Chinese Physics Letters 2010年第12期27卷 65-68页

作者：李犇陈景标 Institute of Quantum Electronics and State Key Laboratory of Advanced Optical Communication System ~z Network School of Electronics Engineering & Computer Science Peking University Beijing 100871

The quantum phase transition from the Mott insulator to the superfluid phases of the bosonic atoms trapped in an optical lattice, in which the on-site interaction carl be tuned by a Feshbach resonance, is investigated by a variational approach within mean-field theory. We derive an extended Bos^Hubbard model to describe this ultracold atomic system. By theoretical calculation and analysis, the phase diagram is shown clearly, and we find an exciting and novel phenomenon that is the appearance of the Mort insulator-sea （MI-sea）. Meanwhile, the experimental feasibility of observing the MI-sea is discussed by analyzing the published data related to the Fashbaeh resonance at present. Finally, the potential application of the MI-sea for quantum information processing and quantum computation is also discussed in detail

关键词： Atomic and molecular physics Quantum gases, liquids and solids Computational physics Statistical physics and nonlinear systems

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Mechanical and tribological performance of CoCrNiHf_(x)eutectic medium-entropy alloys

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Journal of Materials Science & Technology 2021年第31期90卷 194-204页

作者： Yin Du Xuhui Pei Zhaowu Tang Fan Zhang Qing Zhou Haifeng Wang Weimin Liu State Key Laboratory of Solidiﬁcation Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China State Key Laboratory of ASIC and System School of MicroelectronicsFudan UniversityShanghai 200433China

The excellent properties of the multi-principal element alloys(e.g.,the CoCrNi medium-entropy alloy)make them a perfect candidate for structure *** low strength and poor wear-resistance,however,limit considerably their *** this study,a lamellar eutectic microstructure was introduced by addition of Hf into CoCrNi alloy to produce a series of CoCrNiHf_(x)(x=0.1,0.2,0.3 and 0.4)eutectic medium-entropy alloys.A homogeneous eutectic microstructure with an alternate array of the soft FCC solid-solution phase and the hard Laves phase was identified for the as-cast CoCrNiHf_(0.3)*** an investigation of the microstructure,mechanical and tribological properties,it was found that the hardness(plasticity)increases(decreases)with the increasing volume fraction of the Laves phase and the CoCrNiHf_(0.3)eutectic alloy exhibits both good plasticity and high *** wear behavior is strongly dependent on the applied normal *** a low normal load,its tribological behavior follows the Archard's equation and a higher hardness due to Hf addition can resist plastic deformation and abrasive *** the normal load is high enough,the hypoeutectic or hypereutectic alloy,which possessing either high strength or good ductility but not at the same time,exhibit a poor wear *** comparison,the full eutectic CoCrNiHf_(0.3)alloy with a superior combination of strength and toughness shows the best wear performance,as it can significantly reduce fracture during wear.

关键词： Medium-entropy alloy Lamellar eutectics Hardness Plasticity Wear-resistance

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