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science china(Physics,Mechanics & Astronomy) 2016年第12期59卷 33-39页

作者： BaoQuan Ou Jie Zhang XinFang Zhang Yi Xie Ting Chen ChunWang Wu Wei Wu PingXing Chen Department of Physics Science College National University of Defense Technology Interdisciplinary center for Quantum information National University of Defense Technology

In this paper we report the optimal design and fabrication of a gold-on-silica linear segmented surface-electrode ion trap. By optimizing the thickness and width of the electrodes, we improved the trapping ability and trap scalability. By using some practical experimental operation methods, we successfully minimized the trap heating rate. Consequently, we could trap a string of up to 38 ions, and a zigzag structure with 24 ions, and transport two trapped ions to different zones. We also studied the influences of the ion chip surface on the ion lifetime. The excellent trapping ability and flexibility of operation of the planar ion trap shows that it has high feasibility for application in the development a practical quantum information processor or quantum simulator.

关键词： quantum information processor quantum simulator ion trap surface-electrode trap ion string ion transportation

Method of simulating hybrid STT-MTJ/CMOS circuits based on MATLAB/Simulink

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Chinese Physics B 2023年第7期32卷 591-597页

作者：冀敏慧张欣苗潘孟春杜青法胡悦国胡佳飞邱伟成彭俊平林珠李裴森 College of Intelligence science and technology National University of Defense TechnologyChangsha 410073China Beijing National Research center for information science and technology Tsinghua UniversityBeijing 100084China

The spin-transfer-torque(STT)magnetic tunneling junction(MTJ)device is one of the prominent candidates for spintronic logic circuit and neuromorphic ***,building a simulation framework of hybrid STT-MTJ/CMOS(complementary metal-oxide-semiconductor)circuits is of great value for designing a new kind of computing paradigm based on the spintronic *** this work,we develop a simulation framework of hybrid STT-MTJ/CMOS circuits based on MATLAB/Simulink,which is mainly composed of a physics-based STT-MTJ model,a controlled resistor,and a current *** the proposed framework,the STT-MTJ model,based on the Landau-Lifshitz-Gilbert-Slonczewsk(LLGS)equation,is implemented using the MATLAB *** proposed simulation framework is modularized design,with the advantage of simple-to-use and *** prove the effectiveness of the proposed framework,the STT-MTJ model is benchmarked with experimental ***,the pre-charge sense amplifier(PCSA)circuit consisting of two STT-MTJ devices is validated and the electrical coupling of two spin-torque oscillators is *** results demonstrate the effectiveness of our simulation framework.

关键词： magnetic tunneling junction(MTJ)model spin-transfer-torque(STT) circuit simulation MATLAB/Simulink

The impact of honesty and trickery on a Bayesian quantum prisoners’ dilemma game

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Chinese Physics B 2020年第7期29卷 221-227页

作者： Bo-Yang Liu Xin Zhao Hong-Yi Dai Ming Zhang Ying Liao Xiao-Feng Guo Wei Gao information Engineering University Zhengzhou 450001China College of Artificial Intelligence National University of Defense TechnologyChangsha 410073China Department of Physics College of ScienceNational University of Defense TechnologyChangsha 410073China Interdisciplinary center for Quantum information National University of Defense TechnologyChangsha 410073China

To explore the influence of quantum information on the common social problem of honesty and trickery,we propose a Bayesian model for the quantum prisoners’dilemma *** this model,the players’strategy formation is regarded as a negotiation of their move contract based on their types of decision policies,honesty or *** the implementation of quantum information cannot eliminate tricky players,players in our model can always end up with higher payoffs than in the classical *** a good proportion of a credibility parameter value,a rational player will take an honest action,which is in remarkable contrast to the observation that players tend to defect in the classical prisoners’dilemma *** research suggests that honesty will be promoted to enhance cooperation with the assistance of quantum information resources.

关键词： quantum game Bayesian game quantum contract

Optically pumped quantum M_x-M_R magnetometer with high oscillating magnetic field

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Chinese Physics B 2015年第8期24卷 291-295页

作者：丁志超袁杰汪之国杨开勇罗晖 College of Optoelectronic science and Engineering National University of Defense Technology Interdisciplinary center for Quantum information National University of Defense Technology

A dip of the transverse component of the magnetic moment as a function of resonance frequency-detuning will emerge when the intensity of oscillating magnetic field exceeds a specific value, which is demonstrated theoretically and experimentally. The linewidth of magnetic-resonance signal can be much smaller than when the Mx–MR magnetometer operates on condition that the intensity of oscillating magnetic field is smaller than this specific value, and the Mx–MR magnetometer can possess a much higher signal-to-noise ratio. The experimental result shows that the sensitivity of Mx–MR magnetometer can be improved by an order of magnitude under this condition.

关键词： magnetic moment linewidth Mx–MR magnetometer sensitivity

Enabling entity discovery in indoor commercial environments without pre-deployed infrastructure

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Frontiers of Computer science 2019年第3期13卷 618-636页

作者： Bo YUAN Xiaolei ZHOU Xiaoqiang TENG Deke GUO science and technology on information Systems Engineering Laboratory National University of Defense Technology Changsha 410073 China

Finding entities of interest in indoor commercial places, such as the merchandise in supermarkets and shopping malls, is an essential issue for customers, especially when they are unfamiliar with an ad hoc indoor environment. This type of location-based indoor service requires comprehensive knowledge of indoor entities, including locations as well as their semantic information. However, the existing indoor localization approaches fail to directly localize these general entities without dedicated devices. This paper first focuses on the problem of discovering large-scale general entities of interest in indoor commercial spaces without pre-deployed infrastructure. We present a unique entity localization approach that leverages the localization results from multiple independent users to accurately determine the location of corresponding entities. Our key idea is to exploit the short-distance estimation with dead reckoning to guarantee the accuracy of entity localization. We develop a prototype system based on the crowdsourcing method, iScan, and test it in one of the biggest supermarkets in Changsha, china, to validate the performance of our design. Extensive experimental results show that our approach can achieve meter-level accuracy in a single day with 70 participants. Moreover, in a monthly evaluation with 500 effective participants, iScan discovered more than 200 entities and localized approximately 75% of them within 2 m.

关键词： indoor localization entity discovery crowdsourcing system location-based service

Uncertain multicast under dynamic behaviors

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Frontiers of Computer science 2020年第1期14卷 130-145页

作者： Yudong QIN Deke GUO Zhiyao HU Bangbang REN science and technology on information System Engineering Laboratory National University of Defense TechnologyChangsha 410073China

Multicast transfer can efficiently save the bandwidth consumption and reduce the load on the source node than a series of independent unicast ***,many applications employ the content replica strategy to improve the robustness and efficiency;hence each file and its replicas are usually distributed among multiple *** such scenarios,the traditional deterministic multicast develops into the Uncertain multicast,which has more flexibility in the source *** this paper,we focus on building and maintaining a minimal cost forest(MCF)for any uncertain multicast,whose group members(source nodes and destination nodes)may join or leave after constructing a *** formulate this dynamic minimal cost forest(DMCF)problem as a mixed integer programming *** then design three dedicated methods to approximate the optimal *** them,our a-MCF aims to efficiently construct an MCF for any given uncertain multicast,without dynamic behaviors of multicast group *** d-MCF method motivates to slightly update the existing MCF via local modifications once appearing a dynamic *** can achieve the balance between the minimal cost and the minimal modifications to the existing *** last r-MCF is a supplement method to the d-MCF method,since many rounds of local modifications maymake the resultant forest far away from the optimal ***,our r-MCF method monitors the accumulated degradation and triggers the rearrangement process to reconstruct an new MCF when *** comprehensive evaluation results demonstrate that our methods can well tackle the proposed DMCF problem.

关键词： uncertain multicast dynamic behaviors routing forest approximation algorithm Steiner tree

Functionality evaluation of system of systems architecture based on extended influence diagrams

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Journal of Systems Engineering and Electronics 2018年第3期29卷 510-518页

作者： ZHANG Mengmeng CHEN Honghui ZHANG Xiaoxue LUO Aimin LIU Junxian science and technology on information Systems Engineering Laboratory National University of Defense TechnologyChangsha 410072China

System of systems architecture（SoSA） has received increasing emphasis by scholars since Zachman ignited its flame in 1987. Given its complexity and abstractness, it is critical to validate and evaluate SoSA to ensure requirements have been *** qualities are discussed in the literature of SoSA evaluation, while research on functionality is scarce. In order to assess SoSA functionality, an extended influence diagram（EID） is developed in this paper. Meanwhile, a simulation method is proposed to elicit the conditional probabilities in EID through designing and executing SoSA. An illustrative anti-missile architecture case is introduced for EID development, architecture design, and simulation.

关键词： system of systems architecture(SoSA) functionality evaluation extended influence diagram(EID) anti-missile architecture simulation

Guaranteeing the response deadline for general aggregation trees

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Frontiers of Computer science 2020年第6期14卷 97-110页

作者： Jiangfan LI Chendie YAO Junxu XIA Deke GUO science and technology on information Systems Engineering Laboratory National University of Defense TechnologyChangsha 410073China

It is essential to provide responses to queries within time deadlines,even if not exact and *** reduce the query latency,systems usually partition large-scale data computations as a series of tasks over many processes and aggregate them to reduce the response time by using aggregation *** obstacle is that the involved processes of a query usually differ in their speeds,thus not all processes can complete their tasks in *** would directly degrade the response quality(the number of outputs received by the root of an aggregation tree).In this paper,we propose a general aggregation tree model,Tarot,to maximize the response quality by systematically addressing the following challenging issues:(1)fine-grained partition of the query deadline along the multi-level aggregation tree;(2)learning the distribution of durations at each level in the aggregation tree to optimize the wait durations at aggregators;(3)adaptively reassigning tasks over processes according to their status;(4)performing periodic aggregation of received outputs from the low level to avoid missing the *** prior model does not consider the four aspects *** evaluations indicate that Tarot can adapt to multi-level trees and considerably improve the response quality compared to prior work while guaranteeing the query deadline.

关键词： aggregation query performance variations tasks reassignment

Decoupled Two-Phase Framework for Class-Incremental Few-Shot Named Entity Recognition

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Tsinghua science and technology 2023年第5期28卷 976-987页

作者： Yifan Chen Zhen Huang Minghao Hu Dongsheng Li Changjian Wang Feng Liu Xicheng Lu College of Computer National University of Defense TechnologyChangsha 410073China information Research center of Military science PLA Academy of Military ScienceBeijing 100091China

Class-Incremental Few-Shot Named Entity Recognition(CIFNER)aims to identify entity categories that have appeared with only a few newly added(novel)class ***,existing class-incremental methods typically introduce new parameters to adapt to new classes and treat all information equally,resulting in poor ***,few-shot methods necessitate samples for all observed classes,making them difficult to transfer into a class-incremental ***,a decoupled two-phase framework method for the CIFNER task is proposed to address the above *** whole task is converted to two separate tasks named Entity Span Detection(ESD)and Entity Class Discrimination(ECD)that leverage parameter-cloning and label-fusion to learn different levels of knowledge separately,such as class-generic knowledge and class-specific ***,different variants,such as the Conditional Random Field-based(CRF-based),word-pair-based methods in ESD module,and add-based,Natural Language Inference-based(NLI-based)and prompt-based methods in ECD module,are investigated to demonstrate the generalizability of the decoupled *** experiments on the three Named Entity Recognition(NER)datasets reveal that our method achieves the state-of-the-art performance in the CIFNER setting.

关键词： named entity recognition deep learning class-incremental learning few-shot learning

Spin dynamics of magnetic resonance with parametric modulation in a potassium vapor cell

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Chinese Physics B 2017年第3期26卷 285-290页

作者：张锐汪之国彭翔黎文浩李松健郭弘 College of science and Interdisciplinary Center for Quantum Information National University of Defense Technology Changsha 410073 China State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science and Center for Quantum Information Technology Peking University Beijing 100871 China College of Optoelectronic science and Engineering National University of Defense Technology Changsha 410073 China

A typical magnetic-resonance scheme employs a static bias magnetic field and an orthogonal driving magnetic field oscillating at the Larmor frequency, at which the atomic polarization precesses around the static magnetic field. Here we demonstrate both theoretically and experimentally the variations of the resonance condition and the spin precession dynamics resulting from the parametric modulation of the bias field. We show that the driving magnetic field with the frequency detuned by different harmonics of the parametric modulation frequency can lead to resonance as well. Also, a series of frequency sidebands centered at the driving frequency and spaced by the parametric modulation frequency can be observed in the precession of the atomic polarization. We further show that the resonant amplitudes of the sidebands can be controlled by varying the ratio between the amplitude and the frequency of the parametric modulation. These effects could be used in different atomic magnetometry applications.

关键词： atomic magnetometer magnetic resonance parametric modulation