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Atmospheric and oceanic responses to Super Typhoon Mangkhut in the South China Sea:a coupled CROCO-WRF simulation

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Journal of Oceanology and limnology 2023年第4期41卷 1369-1388页

作者： mingyu li Yijun HE Guoqiang liU School of Marine Sciences Nanjing University of Information Science and TechnologyNanjing 210044China Marine Science and Engineering Guangdong Laboratory Zhuhai 519000China Department of Engineering Mathematics and Internetworking Dalhousie UniversityHalifax B3H 4R2Canada Bedford Institute of Oceanography Fisheries and Oceans CanadaDartmouth B2Y 4A2Canada

The South China Sea(SCS)is the largest marginal sea in the Northwest Pacific Ocean,and it encounters frequent *** atmosphere and ocean will create significant thermal and dynamic responses during the intense disturbance caused by ***,these responses have not been thoroughly investigated owing to the complicated marine *** to the satellite data,the SCS Basin was observed to have a strong sea surface temperature(SST)response to Typhoon Mangkhut,resulting in widespread SST cooling.A coupled model was used to investigate the atmospheric and oceanic responses to Typhoon ***-track data,satellite SST,and ARGO measurements show that the coupled WRF-CROCO simulation displays better track,intensity,SST,temperature,and salinity profiles than those of the WRF-only *** show that the typhoon induced rightward intensifications in wind speed,ocean current,and *** following are some remarkable atmosphere and ocean responses:(1)the SST below the inner-core region is cooled by 1℃,resulting in a 37%-44%decrease in wet enthalpy,and the central pressure is increased by~9 ***,the changes in SST below the innercore region of the SCS Basin have a significant impact on air-sea fluxes under high-wind conditions;(2)the ocean boundary layer analysis shows that near-inertial oscillations on the right side of the typhoon track and a strong inertial current up to~2.28 m/s in the upper ocean were observed,which resonated with the local wind and flow field on the right side and induced strong SST cooling;(3)a decrease in SST decreased the moist static energy of the typhoon boundary layer,thereby weakening the typhoon’s *** difference in equivalent potential temperature and sea surface pressure have a good correlation,indicating that the influence of moist static energy on typhoon intensity cannot be overlooked.

关键词： Super Typhoon Mangkhut coupled ocean-atmosphere model wet enthalpy inertial current

Design, fabrication and performance test of an integrated exploding foil initiator system

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Defence Technology（防务技术） 2024年第12期42卷 125-135页

作者： Zehao Wang Pengfei Xue Qingxuan Zeng mingyu li State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Institute of Chemical Materials China Academy of Engineering PhysicsMianyang621900China

The integration method of exploding foil initiator system(EFIs) used to be researched to broaden its application range in military and aerospace in the last few *** order to lower the firing voltage below 1 kV,an integrated EFIs with enhanced energy efficiency was *** exploding foil initiator chips were fabricated in batch via micro electromechanical systems technology by integrating a unified foil,a flyer layer and a barrel on a glass substrate successively,meanwhile its package of the whole system was proposed at a volume of 2.194 cm^(3).The structural parameters were determined by predicted performance including flyer velocity,impact behavior and conduction property via the proposed theoretical models and the static electric field *** expect,this integrated EFIs exhibited excellent functions,which could accelerate the flyer to a terminal velocity over 4 km/s and preeminently initiate HNS-IV pellet at a circuit of 0.24 μF/0.9 ***,the theoretical design,fabrication and performance test have been all included to validate the feasibility of this integrated EFIs that was beneficial for its commercial development in the future.

关键词： Exploding foil initiator system Integration Planar trigger switch Micro electromechanical systems Flyer velocity Shock initiation

Failure Modes of Lead Free Solder Bumps Formed by Induction Spontaneous Heating Reflow

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Journal of Materials Science & Technology 2007年第1期23卷 61-67页

作者： mingyu li Hongbo XU Jongmyung KIM Hongbae KIM Shenzhen Graduate School Harbin Institute of Technology Shenzhen 518055 China Jeonnam Provincial College Jeonnam 517-802 Korea

The shear failure modes and respective failure mechanism of Sn3.5Ag and Sn3.0Ag0.5Cu lead-free solder bumping on Au/Ni/Cu metallization formed by induction spontaneous heating reflow process have been investigated through the shear test after aging at 120℃ for 0, 1, 4, 9 and 16 d. Different typical shear failure behaviors have been found in the loading curves （shear force vs displacement）. From the results of interracial morphology analysis of the fracture surfaces and cross-sections, two main typical failure modes have been identified. The probabilities of the failure modes occurrence are inconsistent when the joints were aged for different times. The evolution of the brittle NiaSn4 and Cu-Ni-Au-Sn layers and the grains coarsening of the solder bulk are the basic reasons for the change of shear failure modes.

关键词： Induction spontaneous heating reflow Lead free solder Shear test Failure mode

Shear Deformation Behaviors of Sn3.5Ag Lead-free Solder Samples

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Journal of Materials Science & Technology 2013年第5期29卷 471-479页

作者： Jing Han Hongtao Chen mingyu li Chunqing Wang Department of Materials Science and Engineering Shenzhen Graduate SchoolHarbin Institute of Technology State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology

In this study, shear tests have been performed on the as-reflowed Sn3.5Ag solder bumps and joints to investigate the deformation behavior of Sn3.5Ag lead-free solder samples. Scanning electron microscopy （SEM） was employed to characterize the microstructures of the samples and orientation imaging microscopy （OIM） with electron backscattered diffraction （EBSD） in SEM was used to obtain crystallographic orientation of grains to provide a detailed characterization of the deformation behavior in Sn3.5Ag solder samples after shear tests. The deformation behavior in solder samples under shear stress was discussed. The experimental results suggest that the dynamic recrystallization could occur under shear stress at room temperature and recrystallized grains should evolve from subgrains by rotation. Compared with that of non-recrystallized and as-reflowed microstructures, the microhardness of the recrystallized microstructure decreased after shear tests.

关键词： Shear test Deformation behavior Lead-free solder Electron backscattered diffraction Dynamic recrystallization Microhardness

Influence of Thermal Cycling on the Microstructure and Shear Strength of Sn3.5Ag0.75Cu and Sn63Pb37 Solder Joints on Au/Ni Metallization

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Journal of Materials Science & Technology 2007年第1期23卷 68-72页

作者： Hongtao CHEN Chunqing WANG mingyu li Dewen TIAN Micro joining Lab. School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China Department of Materials Science and Engineering Jiamusi University Jiamusi 154007 China Harbin Institute of Technology Shenzhen Graduate School Shenzhen 518055 China

The influence of thermal cycling on the microstructure and joint strength of Sn3.5Ag0.75Cu （SAC） and Sn63Pb37 （SnPb） solder joints was investigated. SAC and SnPb solder balls were soldered on 0.1 and 0.9 μm Au finished metallization, respectively. After 1000 thermal cycles between -40℃ and 125℃, a very thin intermetallic compound （IMC） layer containing Au, Sn, Ni, and Cu formed at the interface between SAC solder joints and underneath metallization with 0.1 μm Au finish, and （Au, Ni, Cu）Sn4 and a very thin AuSn-Ni-Cu IMC layer formed between SAC solder joints and underneath metallization with 0.9 μm Au finish. For SnPb solder joints with 0.1 μm Au finish, a thin （Ni, Cu, Au）3Sn4 IMC layer and a Pb-rich layer formed below and above the （Au, Ni）Sn4 IMC, respectively. Cu diffused through Ni layer and was involved into the IMC formation process. Similar interfacial microstructure was also found for SnPb solder joints with 0.9μm Au finish. The results of shear test show that the shear strength of SAC solder joints is consistently higher than that of SnPb eutectic solder joints during thermal cycling.

关键词： Sn3.5Ag0.75Cu Solder joint Au finish Intermetallic compound

Simplified quantitative analysis method and its application in the insitu synthesized copper-based azide chips

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Defence Technology（防务技术） 2024年第2期32卷 309-316页

作者： Jie Ren Yunfeng li mingyu li Xingyu Wu Jiabao Wang Qingxuan Zeng State Key Laboratory of Explosion and Technology Beijing Institute of TechnologyBeijing 100081China

Copper-based azide(Cu(N_(3))2 or CuN_(3),CA)chips synthesized by in-situ azide reaction and utilized in miniaturized explosive systems has become a hot research topic in recent ***,the advantages of in-situ synthesis method,including small size and low dosage,bring about difficulties in quantitative analysis and differences in ignition capabilities of CA *** aim of present work is to develop a simplified quantitative analysis method for accurate and safe analysis of components in CA chips to evaluate and investigate the corresponding ignition *** this work,Cu(N_(3))2 and CuN_(3)components in CA chips were separated through dissolution and distillation by utilizing the difference in solubility and corresponding content was obtained by measuring N_(3)-concentration through *** spectrophotometry method was optimized by studying influencing factors and the recovery rate of different separation methods was studied,ensuring the accuracy and reproducibility of test *** optimized method is linear in range from 1.0-25.0 mg/L,with a correlation coefficient R^(2)=0.9998,which meets the requirements of CA chips with a milligram-level content *** with the existing ICP method,component analysis results of CA chips obtained by spectrophotometry are closer to real component content in samples and have satisfactory ***,as its application in miniaturized explosive systems,the ignition ability of CA chips with different component contents for direct ink writing CL-20 and the corresponding mechanism was *** study provided a basis and idea for the design and performance evaluation of CA chips in miniaturized explosive systems.

关键词： Copper-based azide chips Spectrophotometry Separation method Quantitative analysis Ignition ability

Study on theoretical model for electrical explosion resistivity of Al/Ni reactive multilayer foil

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Defence Technology（防务技术） 2024年第2期32卷 348-356页

作者： Zehao Wang Tao Wang Pengfei Xue mingyu li Qingxuan Zeng State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China China Ship Development and Design Center Wuhan 430064China

Al/Ni reactive multilayer foil(RMF)possesses excellent comprehensive properties as a promising substitute for traditional Cu bridge.A theoretical resistivity model of Al/Ni RMF was developed to guide the optimization of ***/Ni RMF with different bilayer thicknesses and bridge dimensions were prepared by MEMS technology and electrical explosion tests were carried *** to physical and chemical reactions in bridge,the electrical explosion process was divided into 5 stages:heating of condensed bridge,vaporization and diffusion of Al layers,intermetallic combination reaction,intrinsic explosion,ionization of metal gases,which are obviously shown in measured voltage *** of interface and grain boundary scattering on the resistivity of film metal were *** on variations of substance and state,the resistivity was developed as a function of temperature at each *** explosion curves were calculated by this model at different bilayer thicknesses,bridge dimensions and capacitor voltages,which showed an excellent agreement with experimental ones.

关键词： Al/Ni reactive multilayer foil Electrical explosion Resistivity model Phase transition Calculation

Prediction of Ground Vibration Induced by Rock Blasting Based on Optimized Support Vector Regression Models

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3147-3165页

作者： Yifan Huang Zikang Zhou mingyu li Xuedong Luo Faculty of Engineering China University of GeosciencesWuhan430074China Institute of Geological Survey China University of GeosciencesWuhan430074China

Accurately estimating blasting vibration during rock blasting is the foundation of blasting vibration *** this study,Tuna Swarm Optimization(TSO),Whale Optimization Algorithm(WOA),and Cuckoo Search(CS)were used to optimize two hyperparameters in support vector regression(SVR).Based on these methods,three hybrid models to predict peak particle velocity(PPV)for bench blasting were ***-eight samples were collected to establish the PPV database,eight initial blasting parameters were chosen as input parameters for the predictionmodel,and the PPV was the output *** predictive performance evaluation indicators,the coefficient of determination(R2),rootmean square error(RMSE),mean absolute error(MAE),and a10-index were *** normalizedmutual information value is then used to evaluate the impact of various input parameters on the PPV prediction *** to the research findings,TSO,WOA,and CS can all enhance the predictive performance of the SVR *** TSO-SVR model provides the most accurate *** performances of the optimized hybrid SVR models are superior to the unoptimized traditional prediction *** maximum charge per delay impacts the PPV prediction value the most.

关键词： Blasting vibration metaheuristic algorithms support vector regression peak particle velocity normalized mutual information

Broadband Dual-Input Doherty Power Amplifier Design Based on a Simple Adaptive Power Dividing Ratio Function

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China Communications 2024年第5期21卷 97-112页

作者： Dai Zhijiang Zhong Kang li mingyu Pang Jingzhou Jin Yi School of Microelectronics and Communication Engineering Chongqing UniversityChongqing 400044China Xi’an Branch of China Academy of Space Technology Xi’an 710100China

In this paper,a simple adaptive power dividing function for the design of a dual-input Doherty power amplifier(DPA)is *** the presented approaches,the signal separation function(SSF)at different frequency points can be characterized by a *** in the practical test,the coefficients of SSF can be determined by measuring a small number of data points of input *** as other dualinput DPAs,the proposed approach can also achieve high output power and back-off efficiency in a broadband operation band by adjusting the power distribution ratio ***,a 1.5-2.5 GHz highefficiency dual-input Doherty power amplifier is implemented according to this *** test results show that the peak power is 48.6-49.7d Bm,and the 6-d B back-off efficiency is 51.0-67.0%,and the saturation efficiency is 52.4-74.6%.The digital predistortion correction is carried out at the frequency points of 1.8/2.1GHz,and the adjacent channel power ratio is lower than-54.5d *** and experiment results can verify the effectiveness and correctness of the proposed method.

关键词： broadband doherty power amplifier dualinput efficiency enhancement load modulation