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Travelling Solitary Wave Solutions for Generalized Time-delayed Burgers-Fisher Equation

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Communications in Theoretical Physics 2009年第8期52卷 284-286页

作者： DENG xi-Jun HAN li-Bo li xi School of Information and Mathematics Yangtze University Jingzhou 434023 China College of Physical Science and Technology Yangtze University Jingzhou 434023 China Department of Mathematics University of Kansas Kansas 66045 USA

In this paper,travelling wave solutions for the generalized time-delayed Burgers-Fisher equation *** using the first-integral method,which is based on the ring theory of commutative algebra,we obtain aclass of travelling solitary wave solutions for the generalized time-delayed Burgers-Fisher equation.A minor error in theprevious article is clarified.

关键词： solitary wave first-integral method ring theory time-delayed Burgers-Fisher equation

Effects of the extrusion parameters on microstructure,texture and room temperature mechanical properties of extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 136-146页

作者： Chenjin Zhang Guangyu Yang Lei xiao Zhiyong Kan Jing Guo Qiang li Wanqi Jie State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China College of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China

Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed *** dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)*** the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical-rare-earth(RE)*** alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening *** results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.

关键词： Mg-rare earth alloys extrusion temperature extrusion ratio extrusion speed strengthening mechanisms

An extended numerical model of the first exothermic peak for three dimensional printed cement-based materials

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 80-88页

作者： Wei JIANG Wenqian li xi CHEN School of Materials Science and Engineering Tongji UniversityShanghai 200092China School of Civil Engineering Tongji UniversityShanghai 200092China

The first exothermic peak of cement-based material occurs a few minutes after mixing,and the properties of three dimensional(3D)printed concrete,such as setting time,are very sensitive to *** this background,based on the classical Park cement exothermic model of hydration,we propose and construct a numerical model of the first exothermic peak,taking into account the proportions of C_(3)S,C_(3)A and quicklime in *** calculated parameters are calibrated by means of relevant published exothermic test *** is found that this developed model offers a good simulation of the first exothermic peak of hydration for C_(3)S and C_(3)A proportions from 0 to 100% of cement clinker and reflects the effect of quicklime content at 8%-10%.The unique value of this research is provision of an important computational tool for applications that are sensitive to the first exothermic peak of hydration,such as 3D printing.

关键词： 3D printed cement-based materials cement hydration the first exothermic peak liquid quick-setting agent numerical model

A WOA-based algorithm for parameter optimization of support vector regression and its application to condition prognostics 36

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A WOA-based algorithm for parameter optimization of support ...

A new method to solve the Reynolds equation including mass-conserving cavitation by physics informed neural networks(PINNs)with both soft and hard constraints

第36届中国控制会议

作者： li sai FANG Huajing School of Automation Key Laboratory of Image Processing and Intelligent ControlMinistry of EducationHuazhong University of Science and Technology

ISBN: (纸本)9781538629185

Condition monitoring is very important for system safety and condition-based *** series prediction capabilities of machine learning like support vector regression(SVR) can be utilized for ***,choosing optimal parameters for SVR is an important step in SVR model design,which heavily affects the performance of ***,a whale optimization algorithm(WOA) based algorithm is proposed for SVR parameters *** proposed algorithm has been evaluated through some benchmark ***,the proposed method with moving window technology is used to condition prognostics of the Tennessee Eastman *** and engineering application show that the SVR-WOA method is effective,by noting that the computation time is shortened in some application scenarios.

关键词： Support vector regression Whale optimization algorithm Parameter optimization Condition prognostics

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Friction 2024年第6期12卷 1165-1175页

作者： Yinhu xi Jinhui DENG Yiling li School of Mechanical Engineering Anhui University of Science and TechnologyHuainan 232001China Ericsson AB Datalinjen 3Linköping 58330Sweden

In this work,a new method to solve the Reynolds equation including mass-conserving cavitation by using the physics informed neural networks(PINNs)is *** complementarity relationship between the pressure and the void fraction is *** are several difficulties in problem solving,and the solutions are ***,the difficulty for considering the pressure inequality constraint by PINNs is solved by transferring it into one equality constraint without introducing *** the void fraction inequality constraint is considered by using the hard constraint with the max-min ***,to avoid the fluctuation of the boundary value problems,the hard constraint method is also utilized to apply the boundary pressure values and the corresponding functions are ***,for avoiding the trivial solution the limitation for the mean value of the void fraction is *** results are validated against existing data,and both the incompressible and compressible lubricant are *** agreement can be found for both the domain and domain boundaries.

关键词： Reynolds equation mass-conserving cavitation physics informed neural networks hard constraints trivial solution

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Journal of Systems Engineering and Electronics 2020年第6期31卷 1167-1177页

作者： PENG Han CHENG Ting li xi School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

In target tracking applications,the Doppler measurement contains information of the target range rate,which has the potential capability to improve the tracking ***,the nonlinear degree between the measurement and the target state increases with the introduction of the Doppler ***,target tracking in the Doppler radar is a nonlinear filtering *** order to handle this problem,the Kalman filter form of best linear unbiased estimation(BLUE)with position measurements is proposed,which is combined with the sequential filtering algorithm to handle the Doppler measurement further,where the statistic characteristic of the converted measurement error is calculated based on the predicted information in the sequential ***,the algorithm is extended to the maneuvering target tracking case,where the interacting multiple model(IMM)algorithm is used as the basic framework and the model probabilities are updated according to the BLUE position filter and the sequential filter,and the final estimation is a weighted sum of the outputs from the sequential filters and the model *** results show that compared with existing approaches,the proposed algorithm can realize target tracking with preferable tracking precision and the extended method can achieve effective maneuvering target tracking.

关键词： Kalman filter best linear unbiased estimation(BLUE) measurement conversion sequential filter

Humidity-control assists high-efficient coal fly ash removal by PTFE membrane

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Chinese Journal of Chemical Engineering 2021年第12期34卷 88-95页

作者： Dongyan li xi Tang Shasha Feng Chemical Engineering Department Nanjing Polytechnic InstituteNanjing 210048China State Key Laboratory of Materials-Oriented Chemical Engineering National Engineering Research Center for Special Separation MembraneNanjing Tech UniversityNanjing 210009China

In the present study,the effects of relative humidity on filtrating coal-fired fly ash with hydrophobic poly tetra fluoroethylene(PTFE) membranes were *** intergranular force of particulate matter at different RH conditions was measured by analyzing the critical angle between *** of humidity(from 30% to 70%) on filtration pressure drop and membrane fouling conditions were *** was found the membrane showed optimal filtration resistance of 530 Pa at RH of 60% and the gas permeance can be maintained at 1440 m^(3)·m^(-2)·h^(-1)·kPa^(-1).Moreover,to optimize the operation parameters for this filtration system,effects of fly ash concentration,diameter,membrane pore size,and gas velocities were systematically investigated.

关键词： Relative humidity Collapse angle Pressure drop Poly tetra fluoroethylene(PTFE)membrane Fly ash

FATIGUE FRACTURE BEHAVIOR OF LOW CARBON MARTENSITE AND MARTENSITE/BAINITE DUPLEX STRUCTURE IN STEEL 20CrMnMo

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Acta Metallurgica Sinica(English Letters) 1992年第3期5卷 212-217页

作者： li Yongjun xi′an Jiaotong University,xi′an,China xi'an Jiaotong Univ Xi'an China

Fatigue crack propagation rate,da/dN,and threshold stress intensity range,ΔK_(th),of steel 20CrMnMo containing low carbon martensite or low carbon martensite/bainite(LCM/B) duplex structure,obtained by oil quenching and austempered at 360℃,have been measured using specimens under four-point *** was also made of the crack path and fracture morphology with relation to *** formation of LCM/B duplex structure,which caused by 20% lower bainite after short-time isothermal treatment,may re- markably increase ΔK_(th)and considerably decrease da/*** effect of microstructure on da/dN and ΔK_(th)was discussed with the emphasis on the crack propagation path.

关键词： low carbon martensite duplex structure fatigue crack propagation rate threshold stress intensity range crack path

Online adaptive dwell scheduling based on dynamic template for PAR

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Journal of Systems Engineering and Electronics 2021年第5期32卷 1119-1129页

作者： TAN Qianqian CHENG Ting li xi School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

An adaptive dwell scheduling algorithm for phased array radar(PAR)is proposed in this *** concept of online dynamic template is introduced,based on which a general pulse interleaving technique for PAR is put *** pulse interleaving condition of the novel pulse interleaving is more intuitive and *** traditional adaptive dwell scheduling algorithm combined with the general novel pulse interleaving technique results in the online adaptive dwell scheduling based on dynamic template for PAR is *** proposed algorithm is suitable for radar tasks with multiple pulse repetition intervals(PRIs),which can be utilized in the actual radar *** the purpose of further improving the scheduling efficiency,an efficient version is *** results demonstrate the effectiveness of the proposed algorithm and the efficient *** proposed efficient algorithm can improve the time utilization ratio(TUR)by 9%,the hit value ratio(HVR)by 3.5%,and reduce the task drop ratio(TDR)by 6%in comparison with existing dwell scheduling algorithms considering pulse interleaving in PAR and the proposed efficient one.

关键词： dynamic template dwell scheduling pulse interleaving