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Electron Beam Curing of Advanced Composites

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Journal of Materials Science & Technology 2000年第6期16卷 627-630页

作者： Gang sui, Weihong ZHONG Dep. of Materials Sci. and Eng. Beijing Univ. of Aeron. and Astron. Beijing 100083 China

The fundamental concept of electron beam method and the application in cure of composites are elaborated in this paper. The components of electron beam curing system are introduced. The mechanisms of interaction between electron beam and polymer matrix composites are presented. Recent studies reported including work of authors themselves on electron beam curing of composites are also discussed. Moreover, the authors believe that it is necessary to do the basic research about understanding how electron beam affects cured network and the mechanical/physical properties of the composites, for establishing a quantitative or semi-quantitative formulation.

关键词： Electron Beam Curing of Advanced Composites EB

Error term concerning number of subgroups of group Z_(m)×Z_(n) with m^(2)+n^(2)≤x

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Frontiers of Mathematics in China 2022年第5期17卷 987-999页

作者： Yankun sui Dan LIU Department of Mathematics China University of Mining and TechnologyBeijing 100083China

Let Zm be the additive group of residue classes modulo *** s(m,n)denote the number of subgroups of the group Z_(m)×Z_(n),where m and n are arbitrary positive *** any x≥1,we consider the asymptotic behavior of D_(s)(... 详细信息

关键词： Number of subgroups asymptotic formula error term exponential sums

Review of Ampharete Malmgren, 1866 (Annelida, Ampharetidae) from China

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Journal of Oceanology and Limnology 2020年第5期38卷 1584-1589页

作者： sui Jixing LI Xinzheng Institute of Oceanology Chinese Academy of SciencesQingdao 266071China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Laboratory for Marine Biology and Biotechnology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China

In this paper,the material of the genus Ampharete Malmgren,1866 from China Seas(Annelida:Ampharetidae)deposited in the collections of the Marine Biological Museum of the Chinese Academy of Sciences(MBMCAS)is reviewed and previous identifi cations *** total,four species were found among all specimens *** previously attributed to ***(Grube,1860)and *** Malmgren,1866 had been misidentifi ed and is now confi rmed as belonging to *** Hessle,1917 and *** nmarchica(Sars,1865),respectively;the presence of *** Eliason,1955 is also confi rmed;***(Annenkova,1929)is recorded for the fi rst time from China.

关键词： Ampharete Polychaeta taxonomy China

Formation mechanism of hydride precipitation in commercially pure titanium

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Journal of Materials Science & Technology 2021年第22期81卷 108-116页

作者： Jingwei Li Xiaocui Li Manling sui Beijing Key Laboratory of Microstructure and Properties of Solids Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing100124China Department of Mechanical Engineering City University of Hong KongHong Kong999077China

Since titanium has high afﬁnity for hydrogen and reacts reversibly with hydrogen,the precipitation of titanium hydrides in titanium and its alloys cannot be *** most common hydride precipitates in α-Ti matrix areγ-hydride and δ-hydride,however their mechanisms for precipitation are still *** the present study,we find that both γ-hydride and δ-hydride phases with different specific orientations were randomly precipitated in the as-received hot forged commercially pure *** addition,a large amount of the titanium hydrides can be introduced into Ti matrix with selective precipitation by using electrochemical ***-corrected scanning transmission electron microscopy is used to study the precipitation mechanisms of the two *** is revealed that the γ-hydride and δ-hydride precipitations are both formed through slip+shuffle mechanisms involving a unit of two layers of titanium atoms,but the difference is that the γ-hydride is formed by prismatic slip corresponding to hydrogen occupying the octahedral sites of α-Ti,while the δ-hydride is formed by basal slip corresponding to hydrogen occupying the tetrahedral sites ofα-Ti.

关键词： Pure titanium Titanium hydride Precipitation mechanism Slip Shuffle

A fatigue damage-cumulative model in peridynamics

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Chinese Journal of Aeronautics 2021年第2期34卷 329-342页

作者： Binchao LIU Rui BAO Fucheng sui Institute of Solid Mechanics School of Aeronautic Science and EngineeingBeihang UniversityBeijing 100083China Shenyang Aircraft Design and Research Institute Shenyang 110801China

While the present structural integrity evaluation method is based on the philosophy of assumed similitude, Fatigue and Damage Tolerance(F&DT) evaluations for next generation of air-vehicles require high-fidelity physical models within cyberspace. To serve the needs of F&DT evaluation in digital twin paradigm, a fatigue damage-cumulative model within peridynamic framework is proposed in this paper. Based on the concept of fatigue element block and damage accumulation law in form of Coffin-Manson relationship, the proposed model applies to both fatigue crack initiation and fatigue crack growth;fatigue crack growth rates under constant-amplitude and simple variable-amplitude block loading cases can be well predicted for three common structural materials without inputs of Paris law parameters. Additionally, the proposed model can also be easily extended to a probabilistic version;for verification, multiple-site-damage problems are simulated and the statistic nature of fatigue process in experiments can be well captured. In the end, main features of the proposed model are summarized, and distinctions from the other models are discussed. There may be a potential for the peridynamic damage-cumulative model proposed in this work to numerically predict fatigue problems in digital twin paradigm for future generations of aerospace vehicles.

关键词： Fatigue crack growth rate Fatigue damage Fatigue element model Fatigue lifetime Multiple site damage Peridynamics

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时间反转短参考正交双倍速DCSK调制方案

沈阳理工大学学报 2025年第1期44卷 25-30,38页

作者：隋涛李宏达沈阳理工大学自动化与电气工程学院沈阳110159 沈阳理工大学信息科学与工程学院沈阳110159

为解决传统差分混沌移位键控(differential chaotic shift keying,DCSK)通信系统传输数据速率低以及安全性差的问题,提出一种时间反转短参考正交双倍速差分混沌移位键控通信系统(time-reversal short reference orthogonal double speed... 详细信息

为解决传统差分混沌移位键控(differential chaotic shift keying,DCSK)通信系统传输数据速率低以及安全性差的问题,提出一种时间反转短参考正交双倍速差分混沌移位键控通信系统(time-reversal short reference orthogonal double speed DCSK,TR-SR-ODBR-DCSK)。该方案利用Walsh函数产生两路正交的混沌信号调制两位数据信息,在同一个时隙内同时传输两个比特信息,信息传输速率提高了一倍,同时提高了通信系统的能量利用率;在此基础上将系统中传输的参考信号进行时间反转,消除同一时隙信号间的相关性,提高系统安全性及信号保密性。利用通用软件无线电外设(universal software radio peripheral,USRP)和LabVIEW仿真软件搭建半实物的仿真平台,仿真结果验证了混沌通信系统的可行性和有效性。

关键词：差分混沌移位键控时间反转传输速率通用软件无线电外设

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Study on the resolution of multi-aircraft flight conflicts based on an IDQN

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Chinese Journal of Aeronautics 2022年第2期35卷 195-213页

作者： Dong sui Weiping XU Kai ZHANG College of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing 211106China

With the rapid growth of flight flow,the workload of controllers is increasing daily,and handling flight conflicts is the main ***,it is necessary to provide more efficient conflict resolution decision-making support for *** to the limitations of existing methods,they have not been widely *** this paper,a Deep Reinforcement Learning(DRL)algorithm is proposed to resolve multi-aircraft flight conflict with high solving ***,the characteristics of multi-aircraft flight conflict problem are analyzed and the problem is modeled based on Markov decision ***,the Independent Deep Q Network(IDQN)algorithm is used to solve the ***,a’downward-compatible’framework that supports dynamic expansion of the number of conflicting aircraft is *** model ultimately shows convergence through adequate ***,the test conflict scenarios and indicators were used to verify the *** 700 scenarios,85.71%of conflicts were successfully resolved,and 71.51%of aircraft can reach destinations within 150 s around original arrival *** contrast,conflict resolution algorithm based on DRL has great advantages in solution *** method proposed offers the possibility of decision-making support for controllers and reduce workload of controllers in future high-density airspace environment.

关键词： Air traffic control Conflict resolution Multi-agent system Multi-aircraft flight conflict Reinforcement learning

Monotonic and nonmonotonic gentzen deduction systems for L_(3)-valued propositional logic

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Frontiers of Computer Science 2021年第3期15卷 123-135页

作者： Cungen CAO Lanxi HU Yuefei sui Key Laboratory of Intelligent Information Processing Institute of Computing TechnologyChinese Academy of SciencesBeijing 100190China School of Computer Science and Technology University of Chinese Academy of SciencesBeijing 100049China

A sequent is a pair(Г,△),which is true under an as-signment if either some formula inГis false,or some formula in △ is *** L3-valued propositional logic,a mulisequent is a triple △|Θ|Г,which is true under an assignment if either some formula in △ has truth-value t,or some formula in Θ has truth-value m,or some formula in Г has truth-value￡.Corre-spondingly there is a sound and complete Gentzen deduction system G for multisequents which is ***,a CO-multisequent is a triple △:Θ:Г,which is valid if there is an assignment v in which each formula in△has truth-value≠t,each formula in Θ has truth-value≠m,and each formula in Г has truth-value≠￡.Correspondingly there is a sound and com-plete Gentzen deduction system G-for co-multisequents which is nonmonotonic.

关键词： three-valued logic multisequent co-multise-quent monotonicity Gentzen deduction system

Review on research and application of mesoporous transitional metal oxides in water treatment

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Frontiers of Environmental Science & Engineering 2013年第6期7卷 795-802页

作者： Minghao sui Lei SHE State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and Engineering Tongji University Shanghai 200092 China

This paper reviews the application of meso- porous transitional metal oxides in water treatment on basis of the catalysis and adsorption. Mesoporous transitional metal oxides are characterized by their intrinsic features, such as a high surface area, a highly ordered array of unidimensional pores with a very narrow pore size distribution, and highly dispersed active sites. Finally, the suggestions of further study on application are proposed.

关键词： mesoporous materials transitional metal oxi-des catalysis adsorption water treatment