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Shortcut-based quantum gates on superconducting qubits in circuit QED

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Chinese Physics B 2021年第8期30卷 535-542页

作者： zheng-Yin zhao Run-Ying Yan zhi-Bo Feng School of Science Xuchang UniversityXuchang 461000China

Construction of optimal gate operations is significant for quantum *** an efficient scheme is proposed for performing shortcut-based quantum gates on superconducting qubits in circuit quantum electrodynamics(QED).Two four-level artificial atoms of Cooper-pair box circuits,having sufficient level anharmonicity,are placed in a common quantized field of circuit QED and are driven by individual classical *** the effect of cross resonance,one-qubit NOT gate and phase gate in a decoupled atom can be implemented using the invariant-based shortcuts to *** the assistance of cavity bus,a one-step SWAP gate can be obtained within a composite qubit-photon-qubit system by inversely engineering the classical *** further consider the gate realizations by adjusting the microwave *** the accessible decoherence rates,the shortcut-based gates have high *** present strategy could offer a promising route towards fast and robust quantum computation with superconducting circuits experimentally.

关键词： superconducting qubit circuit QED quantum gate shortcuts to adiabaticity

Study on coexistence between DCS1800 and TDD-LTE systems in multi-mode terminals

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The Journal of China Universities of Posts and Telecommunications 2014年第6期21卷 24-29页

作者： zheng zhi-hui zhao Cheng-lin Li Bin TAO Hong-bo School of Telecommunication Engineering Beijing University of Posts and Telecommunications The State Radio Monitoring Center Testing Center

It＇s well known that the mobile stations will comprise a wide range of radio access technologies（RAT）, providing user with flexible and efficient access to multi-media service and high data rate communications. Although much work has been done for coexistence analysis between different systems base stations（BS）, most of them have not addressed the interference within multi-mode terminal. Hence, for filling the gap, The authors in the article present coexistence studyies of digital cellular system at 1 800 MHz（DCS1800） and time division duplex long term evolution（TDD-LTE） network in multi-mode terminal with multi-service provisioning. A new system model for coexistence was introduced and how deterministic analysis can be done within the terminal was explained. The interference evaluation model was given based on relations between reference sensitivity and signal-to-noise ratio（SNR）, which is also deduced. The system simulation methodology was provided and assumption used in simulation was given. Simulation results were shown with different system parameters. Numeric results indicate that multi-mode terminal is mainly affected by local interference. The minimum antenna isolation required for a health system operation was provided.

关键词： TDD-LTE systems coexistence analysis multi-mode terminal deterministic analysis sensitivity degradation

Researches of soft-sediment deformation structures and seismites in China—A brief review

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Journal of Palaeogeography 2016年第4期5卷 311-317页

作者： Zeng-zhao Feng zhi-Dong Bao Xiu-Juan zheng Yuan Wang China University of Petroleum(Beijing)

During the past 30 years （1987-2016）, a great progress has been made in researches of soft-sediment deformation structures （SSDS）, seismites and pataeoearthquakes in China. However, the research thought of this academic fietd is not open enough. It is atmost with one viewpoint or one voice, i.e., atmost art the papers pubtished in journals of China considered the layers with SSDS as seismites. On the other hand, the authors are very glad to learn that the professors and students of China University of Petroleum （East China） have proposed different academic viewpoints on the origin of SSDS in Lingshan Istand, Qingdao, Shandong Province, China. It is a very active academic atmosphere. The authors＇ ideas are as follows：（1） The SSDS are sedimentary structures with multi-origin. The term ＂SSDS＂ is a good sedimentary and geological term and shoutd be utilized continuat[y. （2） The term ＂seismites＂ is a term which is definitety assigned to the layers with SSDS induced by earthquakes. It is one type of the tayers with SSDS. It is not equal to SSDS. （3） Some geotogists suggested obsoleting the term ＂seismites＂. These suggestions are rational However, since the term ＂seismites＂ has been utilized for a long time in China and worldwide, to obsolete this term should be discussed and agreement should be acquired from numerous geologists in China and worldwide. It may be suitable that let the geological practice decide whether to obsolete it or not. （4） Hopefully, further progress will be made in the researches of SSDS.

关键词： Soft-sediment deformation structures (SSDS) Multi-origin Seismites Pataeoearthquake Ling-shan Island China

Effect of maize sowing area changes on agricultural water consumption from 2000 to 2010 in the West Liaohe Plain, China

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Journal of Integrative Agriculture 2016年第6期15卷 1407-1416页

作者： YANG Ling YANG Yan-zhao FENG zhi-ming zheng Ya-nan Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 P.R. China University of Chinese Academy of Sciences Beijing 100049 P.R. China

The West Liaohe Plain is located in the eastern Inner Mongolia, known as the golden maize belt in China, where maize acreage has continued to rise in recent years. Water is the main limiting factor for maize production in the region, therefore, this study calculated the effect of maize sowing area changes on agricultural water consumption in the West Liaohe Plain in 2000, 2005 and 2010, based on remote sensing and meteorological data. Maize remote sensing classification was con- structed based on moderate-resolution imaging spectroradiometer, normalized difference vegatation index （MODIS NDVI） data. Then the maize sown area and water requirement and irrigation water resources were investigated. Finally, the effect of the maize sowing area changes on agricultural water consumption in the West Liaohe Plain was systematically analyzed in 2000, 2005, and 2010. The results showed that maize sown areas rose from 2000 to 2010 and were concentrated in the center of the West Liaohe Plain. Average per unit maize water deficit amount also increased in an uneven distribution, increasing from the south, east and north to the center and west of the West Liaohe Plain. The per unit area maize water deficit increased from 2000 to 2010, and reached 266 mm in 2000, 272 mm in 2005 and 273 mm in 2010, respectively. and the study concluded that water deficit during the whole growth period of maize in the West Liaohe Plain was defined by a single peak curve. The maize water requirements increased with maize sowing area changes from 2000 to 2010, and the maize water requirements increased from 0.89 billion m3 in 2000 to 1.19 billion m3 in 2005, and 1.21 billion m3 in 2010.

关键词： maize maize water requirement irrigation water resources West Liaohe Plain

Effect of titanium microalloying on microstructure and mechanical properties of vanadium microalloyed steels for hot forging

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Journal of Iron and Steel Research International 2022年第2期29卷 295-306页

作者： Fan zhao Guo-ning He Ya-zheng Liu zhi-hao Zhang Jian-xin Xie Beijing Laboratory of Metallic Materials and Processing for Modern Transportation Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing100083China State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan430074HubeiChina School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China

Effect of titanium microalloying on the microstructure and mechanical properties of vanadium microalloyed steels for hot forging was *** microalloying improves the mechanical properties mainly through refining the austenite *** the heating temperature is in the range of 1050–1300℃,the austenite grain diameter is decreased from 77–133 to 26–68μm by titanium *** the decrease in austenite grain diameter,the final microstructure is refined significantly,and the high misorientation boundaries are *** the steel is heated at 1200℃(the common hot forging temperature)and cooled slowly,titanium microalloying decreases the yield strength from 548.4 to 519.4 MPa,and the tensile strength decreases from 842.7 to 808.7 ***,the elongation increases from 19.0%to 21.4%,and the impact energy increases from 9.8 to 38.2 J.V–Ti steel has a better combination of strength,plasticity and toughness than V *** addition,the nucleation of intragranular ferrite idiomorphs is promoted by titanium microalloying,which may have a beneficial effect on the property of steels with coarse microstructure caused by the critical deformation in hot die forging.

关键词： Titanium microalloying Microalloyed steel Microstructure Mechanical property Intragranular ferrite

Digital microstructure insights to phase evolution and thermal flow properties of hydrates by X-ray computed tomography

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Science China(Technological Sciences) 2021年第1期64卷 187-202页

作者： zhao zhi ZHOU XiaoPing School of Civil Engineering Chongqing UniversityChongqing 400045China

Natural gas-hydrates are valuable energy resource with rich deposits,and their thermal transport and thermal dynamic mechanical behaviors significantly affect the long-term production process and phase change-based thermal energy storage characteristics of these energy *** paper aims to propose novel relations to predict the thermophysical properties,to investigate the hydrate phase evolution in microstructures,and to study the thermal transport and thermal dynamic mechanical *** formation experiments in sandpack samples and ultrasonic wave tests are conducted with the aid of X-ray CT *** microstructures models and variables are defined to describe the hydrate phase evolution,and novel relations are proposed to accurately predict the thermophysical properties based on the microporosity and ultrasonic wave *** thermal transport and thermal dynamic mechanical properties in microstructures with hydrate,water,residuary pore and grain phases are *** show that the average errors of porosity,P-wave and S-wave velocities between the experimental data and computed results by the proposed relations are less than 5%,indicating the accuracy and reliability of the proposed *** temperature fraction decreases with increasing underground temperature and decreasing hydrate *** thermal stress and thermal displacement increase as temperature and hydrate saturation *** are strong anisotropy for the temperature fraction,thermal stress and thermal displacement during the thermal transport of hydrates.

关键词： X-ray computed tomography imaging hydrate phase evolution transport properties effective thermal conductivity thermal-mechanical properties

Personalized federated few-shot node classification

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Science China(Information Sciences) 2025年第1期 204-218页

作者： Yunfeng zhao Xintong HE Guoxian YU Jun WANG Yongqing zheng Carlotta DOMENICONI School of Software Shandong University Joint SDU-NTU Centre for Artificial Intelligence Research Shandong University Department of Mathematics National University of Singapore Department of Computer Science George Mason University

Personalized federated learning(PFL) aims to train customized models for individual clients in a decentralized setting, with the account of non-independent and identically distributed data across clients. However, most PFL methods adopt uniform classification layers for diverse clients and give rise to error-prone predictions, due to the task heterogeneity notably prominent in decentralized graph data scenarios. Although some PFL solutions setup client-specific classification layers for each client and optimize them only locally, they are corrupted with limited local training data. We propose an innovative solution called federated parameter decoupling and node augmentation(Fed PANo) to address these problems and to achieve personalized federated few-shot node classification, which is a prevalent and challenging but unexplored topic. Specifically, Fed PANo first separates the local model into the GNN and classifier to handle unique client-specific task variations. The GNN is trained through federated learning to capture shared knowledge of graph nodes across clients, while the classifier is custom-designed and trained individually for each client. Additionally, a generic classifier shared among clients is adopted to encourage the GNN's grasp of shared information. Then Fed PANo further proposes the node generator along with its local and collaborative training strategies to deal with the node scarcity of clients. Extensive experimental results on benchmark datasets confirm that Fed PANo outperforms eight competitive baselines across different settings.

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Multistable Spatiotemporal Dynamics in the Driven Frenkel-Kontorova Lattice

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Communications in Theoretical Physics 2001年第7期36卷 37-43页

作者： zheng zhi-Gang Department of Physics Beijing Normal University Beijing 100875 China

Spatiotemporal dynamics of the damped dc-driven Frenkel-Kontorova lattice is studied. Multistable topologies are shown. Intermittency of the dynamical contraction factor is found, and this behavior is a consequence of the collisions of kinks and antikinks. Fast kinks and antikinks are unstable. The transition from the localized kink to the whirling mode is found to be a temporal bifurcation cascade of generations of kink-antikink pairs and the collision-induced avalanche dynamics. Noise-induced topology transition is observed and discussed.

关键词： Frenkel-Kontorova model, kink-antikink pair, dynamical contraction factor

Rapid determination of radon monitor＇s calibration factors

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Nuclear Science and Techniques 2016年第5期27卷 188-192页

作者： zhi-Qiang Li De-Tao Xiao Gui-zhi zhao Xi-Jun Wu Jian Shan Qing-zhi Zhou zheng-Zhong He University of South China Hengyang 421001 China Hengyang Normal University Hengyang 421008 China

The monitors used to measure radon concentration must be calibrated,and the calibration factor of each measurement cycle should be ***,the determination time of calibration factors of NRL-Ⅱ radon monitors should be *** this study,a method is proposed to determine the calibration factors of radon monitors *** the proposed method,the calibration factor is initially determined in the 60-min measurement cycle;the calibration factor is then identified in the other measurement cycle on the basis of the principle that the calibration factor of the same radon monitor in different measurement cycles is inversely proportional to the number of a particles produced by ^(218)Po decay in this *** demonstrate that the calculated calibration factor of the different measurement cycles is consistent with the experimental calibration ***,this method is reliable and can be used to determine the calibration factor of radon monitors rapidly.

关键词：校准因子氡浓度监测仪快速测定测量周期监测器测定时间校正因子