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Science China(Information Sciences) 2014年第9期57卷 242-255页

作者： ZHANG WanHong zhou tong HUANG BoXue Department of Automation Tsinghua University Department of Chemical Machinery Qinghai University Tsinghua National Laboratory for Information Science and Technology Tsinghua University

StOMP algorithm is well suited to large-scale underdetermined applications in sparse vector *** can reduce computation complexity and has some attractive asymptotical statistical ***,the estimation speed is at the cost of accuracy *** paper suggests an improvement on the StOMP algorithm that is more efficient in finding a sparse solution to the large-scale underdetermined ***,compared with StOMP,this modified algorithm can not only more accurately estimate parameters for the distribution of matched filter coefficients,but also improve estimation accuracy for the sparse vector *** success boundary is provided based on a large-system limit for approximate recovery of sparse vector by modified algorithm,which validates that the modified algorithm is more efficient than *** computations with simulated data show that without significant increment in computation time,the proposed algorithm can greatly improve the estimation accuracy.

关键词： stagewise orthogonal matching pursuit sparse solution linear underdetermined equations systems biology outlier deletion

Interdecadal Variability in Large and Small Warm Pools in Western Pacific and Their Association with Rainfall Anomalies

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Atmospheric and Oceanic Science Letters 2014年第1期7卷 56-61页

作者： zhou Lian-tong Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of Sciences Key Laboratory of Global Change and Marine-Atmospheric Chemistry

This study investigated interdecadal variability of June–October(JJASO) the large and small warm pools in western Pacific and their association with rainfall anomalies using station and reanalysis data from 1958 to *** results indicated that the large and small warm pools in western Pacific showed an interdecadal shift around *** large warm pool years over western Pacific were found after 1986,whereas the small warm pool years were often seen throughout the periods before *** analysis results also showed that there were obvious interdecadal variability in JJASO rainfall in Southeast China and warm pool in western *** 1958–1985(small warm pool years),the decrease in rainfall was associated with tropospheric moisture divergence and sinking motion over Southeast China and warm pool in western ***,during 1986–2008(large warm pool years),the increase in rainfall was associated with tropospheric moisture convergence and ascending *** analysis showed that large warm pool contributed to the increase in surface latent heat fluxes over warm pool in the western ***,there was an increase in the amount of water vapor over Southeast China and warm pool in western Pacific,which contributed to increased rainfall in these regions.

关键词： large and small warm pools interdecadal variability surface latent heat flux

Research on a six-phase permanent magnet synchronous motor system at dual-redundant and fault tolerant modes in aviation application

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Chinese Journal of Aeronautics 2017年第4期30卷 1548-1560页

作者： Xiaolin KUANG Hong GUO Jinquan XU tong zhou School of Automation Science and Electrical Engineering Beihang University Beij'ing 100083 China

With the development of more/all electrical aircraft technology, an electro-mechanical actuator（EMA） is more and more used in an aircraft actuation system. The motor system, as the crucial part of an EMA, usually adopts the redundancy technology or fault tolerance technology to improve the reliability. To compare the performances of these two motor systems, a 10-pole/12-slot six-phase permanent magnet synchronous motor（PMSM） is designed with the concentrated single-layer winding, which is able to operate at dual-redundant and fault tolerant ***, the position servo performances of the six-phase PMSM at dual-redundant and fault tolerant modes are analyzed, including the normal and fault conditions. In addition, a variable structure proportional-integral-derivative（PID） control strategy is proposed to solve the performance degradation problem caused by phase current saturation. Simulation and experimental results show that the fault tolerant PMSM has a better position servo performance than the dual-redundant PMSM, and the variable structure PID control strategy is able to improve the performance due to phase current saturation.

关键词： Electro-mechanical actua tors Fault tolerant Permanent magnet syn chronous motor Redundancy Variable structure PID control

Robust Stability Analysis of Networked Dynamic Systems with Uncertain Communication Delays 36

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Robust Stability Analysis of Networked Dynamic Systems with ...

Interactions of Soliton Waves for a Generalized Discrete KdV Equation

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作者： ZhiKe Wang tong zhou Department of Automation and TNList Tsinghua University Department of Aviation Theory Air Force Aviation University

ISBN: (纸本)9781538629185

In this paper,we consider robust stability analysis of a networked system with uncertain communication *** subsystem of these systems can have different dynamics,and interconnections among the subsystems are *** is assumed that there exists an uncertain but constant delay in each communication *** on the integral quadratic constraint（IQC）framework,a sufficient robust stability condition is derived in the form of a linear matrix inequality,which depends only on parameters of each subsystem,the subsystem connection matrix（SCM） and the selected IQC *** characteristics lead to an evident computational complexity reduction which is illustrated by some numerical results.

关键词： time delay large scale networked system robust stability integral quadratic constraints

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Communications in Theoretical Physics 2017年第7期67卷 6-12页

作者： tong zhou Zuo-Nong Zhu School of Statistics and Information Shanghai University of International Business and Economics Shanghai 201620 China School of Mathematical Sciences Shanghai Jiao Tong University Shanghai 200240 China

It is well known that soliton interactions in discrete integrable systems often possess new properties which are different from the continuous integrable systems, e.g., we found that there are such discrete solitons in a semidiserete integrable system （the time variable is continuous and the space one is discrete） that the shorter solitary waves travel faster than the taller ones. Very recently, this kind of soliton was also observed in a full discrete generalized KdV system （the both of time and space variables are discrete） introduced by Kanki et al. In this paper, for the generalized discrete KdV （gdKdV） equation, we describe its richer structures of one-soliton solutions. The interactions of two-soliton waves to the gdKdV equation are studied. Some new features of the soliton interactions are proposed by rigorous theoretical analysis.

关键词： generalized discrete KdV equation soliton solution soliton interaction

Enzymes in Nanomedicine for Anti-tumor Therapy

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Chemical Research in Chinese Universities 2023年第1期39卷 72-82页

作者： zhou tong YUAN Shuaiqi QIAN Pinrong WU Yuzhou Hubei Engineering Research Center for Biomaterials and Medical Protective Materials Hubei Key Laboratory of Bioinorganic Chemistry&Materia MedicaKey Laboratory of Material Chemistry for Energy Conversion and StorageMinistry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074P.R.China College of Life Science and Technology Huazhong University of Science and TechnologyWuhan430074P.R.China

Natural enzymes are biological macromolecules catalyzing reactions in living organisms and regulating biological *** delivery of enzymes into tumor tissues for anti-tumor therapy through nanotechnology has attracted emerging interest in recent *** this paper,we systematically summarize the latest research progress on enzymes that used for anti-tumor therapy in nanomedicine with different action mechanisms,including anti-tumor principles,delivery modes,response modes,and synergistic therapeutic design of these ***,we discuss the challenges and future prospects of enzymes for anti-tumor nanomedicine.

关键词： Enzyme Nanomedicine Protein delivery Cancer therapy

Low-dimensional MXenes as noble metal-free co-catalyst for solar-to-fuel production:Progress and prospects

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Journal of Materials Science & Technology 2022年第19期114卷 143-164页

作者： Wanying Lei tong zhou Xin Pang Shixiang Xue Quanlong Xu College of Materials Science and Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Key laboratory of Carbon Materials of Zhejiang Province Wenzhou UniversityWenzhou 325027China

Direct conversion of solar energy into chemical fuels via semiconducting materials through photocatalytic technology is a sustainable way to tackle the global warming, environmental issue and energy crisis. Transition metal carbides and nitrides(MXenes), a newly emerging class of 2D layered materials, has gained tremendous attention as a noble metal-free co-catalyst for boosting photoreactivity due to its extraordinary characteristics like elemental abundance, excellent electrical conductivity, abundant surface functional groups, unique hydrophilic behavior and flexible modulation of chemical composition. The rational integration of low-dimensional MXenes in the form of 2D layered structures or 0D quantum dots with diverse semiconducting materials offer more versatile and robust heterostructured-photocatalysts that are applicable in solar fuel generation. Herein, we summarize the recent advances and achievements in the synthesis of low-dimensional MXenes and their application in hydrogen production from water splitting and CO_(2) photoreduction. A comprehensive discussion of the fundamentals for solar fuel production, synthesis strategies and theoretical calculations for MXenes-based photocatalysts are also given. Finally, the existing challenges and further perspectives of MXenes-based nanostructures for efficient solar fuel production are addressed.

关键词： MXenes Low-dimensional materials Co-catalyst Photocatalytic H_(2)evolution CO_(2)photoreduction

Thiourea crystal growth kinetics,mechanism and process optimization during cooling crystallization

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Chinese Journal of Chemical Engineering 2024年第9期73卷 62-69页

作者： Zhongxiang Ding Wei Song tong zhou Weihua Cui Changsong Wang State Key Laboratory of Materials-Oriented Chemical Engineering Nanjing Tech UniversityNanjing 211816China Yifeng New Material Co. Ltd.Binzhou 256600China

In the cooling crystallization process of thiourea,a significant issue is the excessively wide crystal size distribution(CSD)and the abundance of fine *** investigation delves into the growth kinetics and mechanisms governing thiourea crystals during the cooling crystallization *** fitting results indicate that the crystal growth rate coefficient,falls within the range of 10^(-7)to 10^(-8)m·s^(-1).Moreover,with decreasing crystallization temperature,the growth process undergoes a transition from diffusion-controlled to surface reaction-controlled,with temperature primarily influencing the surface reaction process and having a limited impact on the diffusion *** the crystal growth rate,and the diffusion-limited growth rate,at different temperatures,it is observed that the crystal growth process can be broadly divided into two *** temperatures above 25℃,1/qd(qd is diffusion control index)approaches 1,indicating the predominance of diffusion ***,at temperatures below 25℃,1/qd increases rapidly,signifying the dominance of surface reaction *** address these findings,process optimization was *** the high-temperature phase(35-25℃),agitation was increased to reduce the limitations posed by bulk-phase diffusion in the crystallization *** the low-temperature phase(25-15℃),agitation was reduced to minimize crystal *** optimized process resulted in a thiourea crystal product with a particle size distribution predominantly ranging from 0.7 to 0.9 mm,accounting for 84%of the *** study provides valuable insights into resolving the issue of excessive fine crystals in the thiourea crystallization process.

关键词： Thiourea Crystallization Growth kinetics Process optimization Diffusion Surface reaction

Bending mechanical properties of W/TiN/Ta composites with interfacial TiN coatings

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Rare Metals 2023年第5期42卷 1718-1723页

作者： Gao-Yong Xu tong zhou Ying Zhang Jin-Ping Suo State Key Laboratory of Mould Technology Institute of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Tungsten is one of best candidates for plasma facing materials(PFMs)in fusion *** its application in fusion areas is strongly restricted by the inherent brittleness and high ductile-brittle transition *** improve the toughness of W-based materials,W/TiN/Ta-laminated composites were fabricated by spark plasma ***-point bending test was performed to investigate the bending mechanical *** crack propagation is the main crack propagation mode in W/TiN/Ta *** dissipation by interfacial debonding and crack deflection at interfaces as well as crack bridging by Ta foils and plastic deformation of Ta can contribute to the toughening of W/TiN/Ta *** existence of interfacial TiN coatings can act as weak points and promote interfacial *** coatings with(111)preferred orientation are found to be conducive to the strengthening of W/TiN/Ta composites.

关键词： Multilayer structure Interfacial TiN coatings Bending test Toughness

Optimal design of a novel cylindrical sandwich panel with double arrow auxetic core under air blast loading

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Defence Technology（防务技术） 2020年第3期16卷 617-626页

作者： Xu-ke Lan Qi Huang tong zhou Shun-shan Feng State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

The increasing threat of explosions on the battle field and the terrorist action requires the development of more effective blast resistance materials and *** structure can support the external loads effectively by virtue of their spatial *** review of the excellent energy absorption property of auxetic structure,employing auxetic structure as core material in curved sandwich shows the potential to improve the protection *** this study,a novel cylindrical sandwich panel with double arrow auxetic(DAA) core was designed and the numerical model was built by *** to the complexity of the structure,systematic parameter study and optimal design are *** cases of optimal design were considered,case1 focuses on reducing the deflection and mass of the structure,while case2 focuses on reducing the deflection and increasing the energy absorption per unit *** study and optimal design were conducted based on Latin Hypercube Sampling(LHD)method,artificial neural networks(ANN) metamodel and the nondominated sorting genetic algorithm(NSGA-Ⅱ).The Pareto front was obtained and the cylindrical DAA structure performed much better than its equal solid panel in both blast resistance and energy absorption *** results can be used as a reference for different applications.

关键词： Auxetic structure Blast response Finite element analysis(FEA) Optimal design