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A novel topology with controllable wideband baseband impedance for power amplifiers

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 308-315页

作者： Yao YAO Zhijiang DAI mingyu LI School of Intelligent Technology and Engineering Chongqing University of Science and TechnologyChongqing400065China School of Microelectronics and Communication Engineering Chongqing UniversityChongqing400065China

This paper presents a novel topology to control the baseband impedance of a power amplifier(PA)to avoid performance deterioration in concurrent dual-band *** topology can avoid pure resonance of capacitors and inductors LC,which leads to a high impedance at some frequency ***,it can be applied to transmitters that are excited by broadband *** particular,by adjusting the circuit parameters and increasing stages,the impedance of the key frequency bands can be flexibly controlled.A PA is designed to support this design *** saturated output power is around 46.7 dBm,and the drain efficiency is>68.2%(1.8-2.3 GHz).Under concurrent two-tone excitation,the drain efficiency reaches around 40%even under 5.5 dB back-off power with the tone spacing from 10 MHz to 500 *** results demonstrate that the proposed topology is capable of controlling wideband baseband impedance.

关键词： Baseband impedance Concurrent dual-band Power amplifier

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狮子山楚王陵出土碧玉棺片应为棺体内饰考

江汉考古 2018年第1期 80-88页

作者：葛明宇江苏徐州汉兵马俑博物馆江苏徐州221004

1995年发掘的江苏徐州狮子山西汉楚王陵墓,出土了一具精美的镶玉漆棺。镶玉漆棺出土时已完全残散,根据复原研究修复后为通体镶贴碧玉片版。笔者认为这样复原是不切实际的,本文通过对镶玉漆棺出土状况、构件以及与近年来发现的汉代同类... 详细信息

1995年发掘的江苏徐州狮子山西汉楚王陵墓,出土了一具精美的镶玉漆棺。镶玉漆棺出土时已完全残散,根据复原研究修复后为通体镶贴碧玉片版。笔者认为这样复原是不切实际的,本文通过对镶玉漆棺出土状况、构件以及与近年来发现的汉代同类葬具形制、构造、功能、性质等的分析和比较研究,认为楚王陵镶玉漆棺上的碧玉片应为棺体的内饰。

关键词：狮子山楚王陵镶玉漆棺碧玉片棺体内饰

X-ray Pulsar-based Navigation Method Verification By Insight-HXMT Satellite Data

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X-ray Pulsar-based Navigation Method Verification By Insight...

Mortality from cerebrovascular diseases in China:Exploration of recent and future trends

第十一届中国卫星导航年会

作者： Dapeng Zhang Yidi Wang Wei Zheng mingyu ge State Key Laboratory of Astronautic Dynamics College of aerospace science and engineering National University of Defense Technology Institute of high energy physics CAS

X-ray pulsar-based navigation is a novel spacecraft autonomous navigation method. At present, pulsar-based navigation technology has entered the stage of space experiment verification. In recent years

关键词： X-ray pulsar-based navigation experiment verification Insight-HXMT satellite autonomous navigation

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Chinese Medical Journal 2024年第5期137卷 588-595页

作者： Bin Lv ge Song Feng Jing mingyu Li Hua Zhou Wanjun Li Jiacai Lin Shengyuan Yu Jun Wang Xiangyu Cao Chenglin Tian Department of Neurology The First Medical CenterChinese PLA General HospitalBeijing 100853China Department of Neurology the 305 Hospital of Chinese PLABeijing 100017China Department of Internal Medicine Gucheng County Hospital of Traditional Chinese MedicineHengshuiHebei 253800China Department of Neurology Tangshan Hospital of Traditional Chinese MedicineTangshanHebei 063000China Department of Neurology Hainan Hospital of Chinese PLA General HospitalSanyaHainan 572013China

Background:Cerebrovascular disease(CVD)ranks among the foremost factors responsible for mortality on a global *** mortality patterns of CVDs and temporal trends in China need to be well-illustrated and ***:We collected mortality data on patients with CVD from Chinese Center for Disease Control and Prevention’s Disease Surveillance Points(CDC-DSP)*** mortality of CVD in 2020 was described by age,sex,residence,and *** temporal trend from 2013 to 2019 was evaluated using joinpoint regression,and estimated rates of decline were extrapolated until 2030 using time series ***:In 2019,the age-standardized mortality in China(ASMRC)per 100,000 individuals was *** ASMRC for males(137.7/10^(5))and rural areas(123.0/10^(5))were both higher when stratified by gender and urban/rural *** central region had the highest mortality(126.5/10^(5)),the western region had a slightly lower mortality(123.5/10^(5)),and the eastern region had the lowest mortality(97.3/10^(5)).The age-specific mortality showed an accelerated upward trend from aged 55-59 years,with maximum mortality observed in individuals over 85 years of *** age-standardized mortality of CVD decreased by 2.43%(95%confidence interval,1.02-3.81%)annually from 2013 to ***,the age-specific mortality of CVD increased from 2013 to 2019 for the age group of over 85 *** 2020,both the absolute number of CVD cases and the crude mortality of CVD have increased compared to their values in *** estimated total deaths due to CVD were estimated to reach 2.3 million in 2025 and 2.4 million in ***:The heightened focus on the burden of CVD among males,rural areas,the central and western of China,and individuals aged 75 years and above has emerged as a pivotal determinant in further decreasing mortalities,consequently presenting novel challenges to strategies for disease prevention and control.

关键词： Cerebrovascular diseases Mortality Epidemiology Global Burden of Disease China COVID-19 pandemic

Two-dimensional semiconductor heterostructures for photocatalytic CO_(2)conversion

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Science China Chemistry 2024年第8期67卷 2434-2447页

作者： Yang Wu mingyu Wu Yongfu Sun Yi Xie Hefei National Research Center for Physical Sciences at Microscale University of Science and Technology of ChinaHefei 230026China

The CO_(2)reduction into carbon-contained fuel via solar energy offers the powerful tools to realize the zero-emission carbon *** to the intriguing features of the two-dimensional(2D)heterostructures,it is susceptible to modulate the electronic structure as well as the surface geometry for optimizing the photocatalytic CO_(2)*** this perspective,we surveyed the fundamental insights of 2D semiconductor heterostructures,involving the fabrication strategies and classification of the 2D semiconductor ***,we have detailly discussed the overview of 2D semiconductor heterostructure for optimizing CO_(2)photocatalytic influenced factors,including the solar energy utilization,photogenerated carriers separation,and redox reaction ***,we showed the significant advantages of 2D heterostructures in elevating CO_(2)photoreduction performance,focusing on activity,selectivity and *** analyzing the limitations and developments,we ended by putting forward insights into the further researches about the CO_(2)photocatalysts and reactor design,even industrial applications.

关键词： two-dimensional semiconductor heterostructures photocatalysis CO_(2)conversion

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

Accelerated thermal ageing on performance of polypropylene-based semiconducting screen for high voltage direct current cable applications-Effect of antioxidants

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High Voltage 2024年第2期9卷 410-418页

作者： Haitian Wang Yi Luo mingyu Zhou Xintong Ren george Chen geIRI BerlinGermany The Tony Davies High Voltage Laboratory University of SouthamptonSouthamptonUK

The potential of using eco-friendly thermoplastic polypropylene(PP)-based insulation for high voltage direct current(HVDC)cable has been widely investigated but much less work on the PP-based semiconducting screen(SC).Considering a long service life(>30 years)under high temperature and high electrical stress is required for typical HVDC cables,and investigations on the effect of antioxidant(AO)concentration and thermal oxidative sta-bility,mechanical,and electrical properties of PP-based SCs have been *** has been demonstrated that an appropriate combination and amounts of AOs are critical for achieving high thermal stability and maintaining the mechanical properties of SC after ageing in a harsh environment(150°C,with Cu,in air,7 days).Although higher amounts of space charges have been observed in SC/PP/SC samples with higher AO concentrations,the impact on space charge behaviours is less after ageing,suggesting that ageing(or operating at high temperature)leads to microstructure evolution in SC and can potentially mitigate space accumulation in PP-based insulating materials.

关键词： microstructure thermal high

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