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Fault deformation anomaly and intermedi-ate and short-term prediction of the Jingtai Ms=5.9 earthquake

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Acta Seismologica Sinica(English Edition) 2001年第2期14卷 156-165页

作者： WANG shuang-xu The Second Crustal Deformation Monitoring Center China Seismological Bureau Xi’an China

The time-space distribution characteristics of fault deformation anomaly in the near-source region and its outlying zone in the seismogenic process of the Jingtai Ms=5.9 earthquake occurred on June 6, 2000 in Gansu Province is studied preliminary. The distribution scope of fault deformation anomaly before the earthquake is wide, the anomaly shape is complicated and the pattern anomalous zone of fault deformation (strain) information index is obvious. The shape and amplitude of fault deformation anomaly in different regions differ significantly, which is closely related with the tectonic location of anomaly. The fault deformation anomaly of α β, and γ phases along the western segment of Haiyuan fault zone shows the process from the quasi-linearity to non-linearity of fault movement in the near-source region, matches the high-value anomalous area of fault deformation (strain) information index, and reflects the high strain accumulation in the seismogenic region. However, the anomaly of abrupt jump and cusp with a large amplitude occurred in the areas far from the earthquake, such as Liupanshan fault zone which is the tectonic convergent section does not reflect the strain accumulation of its location, maybe it is a sign that the regional tectonic stress field is strengthened in the seismogenic process. Based on the above-mentioned facts and combined with the preliminary summary of experiences and lessons in the intermediate and short-term prediction of the Jingtai Ms=5.9 earthquake, we study and explore the application of fault deformation anomaly to earthquake judgment.

关键词： Anomaly characteristics Fault deformation Intermediate and short-term earthquake prediction Jingtai Ms=5.9 earthquake

The Shock Response and Spall Mechanism of Mg-Al-Zn Alloy:Molecular Dynamics Study

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Acta Mechanica Solida Sinica 2022年第3期35卷 495-503页

作者： Xiaoyue Yang shuang xu Lisheng Liu Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Shock responses of Mg-Al-Zn alloy are investigated by the molecular dynamics(MD)*** wave propagation,plastic deformation behavior and failure mechanism along the[0001]and[1010]orientations are *** both orientations,simulation results show that the shock wave has an obvious double-wave structure(plastic-elastic)under a piston velocity of 1200 m/s.A higher Hugoniot elastic limit(HEL)is observed for[0001]-oriented *** the shock pressure is along the[1010]direction,the distance between plastic and elastic waves is closer,and higher dislocation density and more twins are ***,the spall strength for[1010]-oriented shock is predicted to be *** addition,the wave interactions,HEL and spall strength predicted for Mg-Al-Zn alloy are compared with the experimental results and MD simulation results of Mg single crystal in the *** is concluded that the shock performance of Mg-Al-Zn is better than that of Mg single crystal.

关键词： Mg-Al-Zn Shock compression Molecular dynamics Hugoniot elastic limit Spall strength

IQABC-Based Hybrid Deployment Algorithm for Mobile Robotic Agents Providing Network Coverage

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Tsinghua Science and Technology 2024年第2期29卷 589-604页

作者： shuang xu Xiaojie Liu Dengao Li Jumin Zhao College of Computer Science and Technology(College of Data Science) Taiyuan University of TechnologyTaiyuan 030024China Pengcheng Laboratory Shenzhen 518055China College of Information and Computer Taiyuan University of TechnologyTaiyuan 030024China

Working as aerial base stations,mobile robotic agents can be formed as a wireless robotic network to provide network services for on-ground mobile devices in a target ***,a challenging issue is how to deploy these mobile robotic agents to provide network services with good quality for more users,while considering the mobility of on-ground *** this paper,to solve this issue,we decouple the coverage problem into the vertical dimension and the horizontal dimension without any loss of optimization and introduce the network coverage model with maximum coverage ***,we propose a hybrid deployment algorithm based on the improved quick artificial bee *** algorithm is composed of a centralized deployment algorithm and a distributed *** proposed deployment algorithm deploy a given number of mobile robotic agents to provide network services for the on-ground devices that are independent and identically *** results have demonstrated that the proposed algorithm deploys agents appropriately to cover more ground area and provide better coverage uniformity.

关键词： wireless robotic networks network coverage deployment algorithm improved quick artificial bee colony

Atomistic simulation of the structural evolution in magnesium single crystal under c-axis tension

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Acta Metallurgica Sinica(English Letters) 2011年第6期24卷 487-494页

作者： Honggang QI Yafang GUO Xiaozhi TANG shuang xu Institute of Engineering Mechanics Beijing Jiaotong University Beijing 100044 China

Molecalar dynamics simulation is applied to investigate the microstructure evolution of magnesium single crystals under c-axis extension at different temperatures. At low temperatures, both {1012} and {1011} twins are observed. At elevated temperatures, {1011} twining decreases quickly with increasing temperature, while the amount of {1012} twins increases. The （1012} twin is found to be the main deformation mechanism under the c-axis tension in the magnesium single crystal. Meanwhile, shear bands are also observed during deformation. When the temperature is beyond 500 K, the non-basal plane slip due to the thermal .activation is found. The stress-strain curves related with deformation behavior at atomistic scale are presented.

关键词： Magnesium single crystal Twinning Molecular dynamics simu-lation c-axis tension

Local-to-Global Causal Reasoning for Cross-Document Relation Extraction

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IEEE/CAA Journal of Automatica Sinica 2023年第7期10卷 1608-1621页

作者： Haoran Wu Xiuyi Chen Zefa Hu Jing Shi shuang xu Bo xu Institute of Automation Chinese Academy of SciencesBeijing 100190China. School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100190China

Cross-document relation extraction(RE),as an extension of information extraction,requires integrating information from multiple documents retrieved from open domains with a large number of irrelevant or confusing noisy *** studies focus on the attention mechanism to construct the connection between different text features through semantic ***,similarity-based methods cannot distinguish valid information from highly similar retrieved documents *** to design an effective algorithm to implement aggregated reasoning in confusing information with similar features still remains an open *** address this problem,we design a novel local-toglobal causal reasoning(LGCR)network for cross-document RE,which enables efficient distinguishing,filtering and global reasoning on complex information from a causal ***,we propose a local causal estimation algorithm to estimate the causal effect,which is the first trial to use the causal reasoning independent of feature similarity to distinguish between confusing and valid information in cross-document ***,based on the causal effect,we propose a causality guided global reasoning algorithm to filter the confusing information and achieve global *** results under the closed and the open settings of the large-scale dataset Cod RED demonstrate our LGCR network significantly outperforms the state-ofthe-art methods and validate the effectiveness of causal reasoning in confusing information processing.

关键词： Causal reasoning cross document graph reasoning relation extraction(RE)

A Knowledge-enhanced Two-stage Generative Framework for Medical Dialogue Information Extraction

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Machine Intelligence Research 2024年第1期21卷 153-168页

作者： Zefa Hu Ziyi Ni Jing Shi shuang xu Bo xu School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China Institute of Automation Chinese Academy of SciencesBeijing 100190China

This paper focuses on term-status pair extraction from medical dialogues(MD-TSPE),which is essential in diagnosis dia-logue systems and the automatic scribe of electronic medical records(EMRs).In the past few years,works on MD-TSPE have attracted increasing research attention,especially after the remarkable progress made by generative ***,these generative methods output a whole sequence consisting of term-status pairs in one stage and ignore integrating prior knowledge,which demands a deeper un-derstanding to model the relationship between terms and infer the status of each *** paper presents a knowledge-enhanced two-stage generative framework(KTGF)to address the above *** task-specific prompts,we employ a single model to com-plete the MD-TSPE through two phases in a unified generative form:We generate all terms the first and then generate the status of each generated *** this way,the relationship between terms can be learned more effectively from the sequence containing only terms in the first phase,and our designed knowledge-enhanced prompt in the second phase can leverage the category and status candidates of the generated term for status ***,our proposed special status"not mentioned"makes more terms available and en-riches the training data in the second phase,which is critical in the low-resource *** experiments on the Chunyu and CMDD datasets show that the proposed method achieves superior results compared to the state-of-the-art models in the full training and low-re-sourcesettings.

关键词： Medical dialogue understanding information extraction text generation knowledge-enhanced prompt low-resource setting dataaugmentation

Traveling through Time and Searching for Utopia： Utopian Imaginaries in Internet Time-Travel Fiction

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Frontiers of Literary Studies in China-Selected Publications from Chinese Universities 2016年第1期10卷 113-132页

作者： shuang xu U.F.R. Langues et Civilisations de l'Asie Orientale Universit4 Paris Diderot - Paris VII Casier 7009 16 rue Marguerite Duras 75205 Paris Cedex 13 France

The time-travel genre of Chinese Internet literature combines old mythological motifs with contemporary science fiction approaches to create a narrative line in which the protagonist travels through time, undergoes a series of trials, discovers new worlds, and realizes an idealized life. Borrowing Foucault＇s theory of utopian bodies and heterotopias and taking Tianxia Guiyuan＇s female-oriented Intemet novel Empress Fuyao as its exemplary case, this study analyzes how time-travel fiction uses time travel in order to image a ＂utopia＂ and what kind of ＂new world＂ is projected by this utopia, In the process, this paper will simultaneously examine the relationship between utopia and twenty-first century China＇s new media literature.

关键词： Internet literature time-travel fiction utopian body heterotopia,Tianxia Guiyuan Empress Fuyao

Designed synthesis of porous carbons for the separation of light hydrocarbons

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Chinese Journal of Chemical Engineering 2022年第2期35卷 130-150页

作者： shuang xu Ru-Shuai Liu Meng-Yao Zhang An-Hui Lu State Key Laboratory of Fine Chemicals Liaoning Key Laboratory for Catalytic Conversion of Carbon ResourcesSchool of Chemical EngineeringDalian University of TechnologyDalian 116024China

The separation of light hydrocarbon mixtures(C_(1)–C_(3))generated from petrochemical industry is vital and challenging process for obtaining valuable pure chemical *** comparison to the energy intensive conventional separation technologies(cryogenic distillation,absorption and hydrogenation),the adsorptive separation is considered as a low energy cost and high efficiency *** carbons have been demonstrated as excellent adsorbents for the separation of light hydrocarbons,owing to their designable structure and tailorable *** review summarizes the recent advances of using porous carbons as adsorbents for the separation of light hydrocarbons,including methane/nitrogen,methane/alkane,methane/carbon dioxide,ethylene/ethane and propylene/*** discuss the separation mechanisms and highlight the material features including pore structure,surface chemistry and target molecular properties that determine the separation ***,the challenges and development direction associated with carbonaceous adsorbents for light hydrocarbon separation are discussed,meanwhile the guidelines for the design of porous carbons are proposed.

关键词： Porous carbon Adsorption Separation Hydrocarbons

Evolution of Single-Phase Power Converter Topologies Underlining Power Decoupling

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Chinese Journal of Electrical Engineering 2016年第1期2卷 24-39页

作者： shuang xu Liuchen Chang Riming Shao Dept of Elec.&Comp.Eng.University of New BrunswickFrederictonNEE3B 5A3Canada

Single-phase power converters are widely used in electric distribution systems under 10 kilowatts,where the second-order power imbalance between the AC side and DC side is an inherent *** pulsating power is decoupled from the desired constant DC power,through an auxiliary circuit using energy storage *** paper provides a comprehensive overview of the evolution of single-phase converter topologies underlining power decoupling *** power decoupling techniques were commonly used in single-phase power converters before active power decoupling techniques were *** then,active power decoupling topologies have generally evolved based on three streams of concepts:1)current-reference active power decoupling;2)DC voltage-reference active power decoupling;and 3)AC voltage-reference active power *** benefits and drawbacks of each topology have been presented and compared with its predecessor,revealing underlying logic in the evolution of the *** addition,a general comparison has also been made in terms of decoupling capacitance/inductance,additional cost,efficiency and complexity of control,providing a benchmark for future power decoupling topologies.

关键词： Power decoupling second-order ripple power single-phase power converter singlephase inverter