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雷达资料循环同化对2021年“4·30”南通雷暴大风模拟的影响研究

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大气科学 2024年第4期48卷 1593-1607页

作者：汪卫国平凡周括李建阳南京信息工程大学遥感与测绘工程学院南京210044 中国科学院大气物理研究所云降水物理与强风暴重点实验室(LACS) 北京100029

基于多普勒天气雷达资料、ERA5再分析资料与地面自动站观测资料,利用WRF(Weather Research and Forecasting)模式、雷达径向风质控及三维变分同化系统(GSI)循环同化对2021年4月30日江苏南通的一次雷暴大风过程进行数值模拟研究,对比分... 详细信息

基于多普勒天气雷达资料、ERA5再分析资料与地面自动站观测资料,利用WRF(Weather Research and Forecasting)模式、雷达径向风质控及三维变分同化系统(GSI)循环同化对2021年4月30日江苏南通的一次雷暴大风过程进行数值模拟研究,对比分析不同试验方案模拟的雷达反射率、风场与热动力的时空演变和结构特征。结果表明:逐30 min循环同化的Exp3方案较未同化和非临近循环同化方案模拟效果有较好提升,表明循环同化和增加频次有效改善了初始场;UNRAVEL退模糊算法质控有效消除了速度模糊,退模糊处理雷达资料后循环同化方案(Exp4)对此次雷暴大风的雷达反射率和地面风场模拟结果有显著调整,其相应特征和演变趋势与观测基本一致,表明UNRAVEL退模糊质控后循环同化更好的改善了初始场;从热动力场结果来看,Exp4方案动热力结构改善较明显,上层辐散下层辐合,存在“冷—暖—冷”的热动力结构,伴随着强烈上升运动、北高南低的气压分布和强垂直风切变,有助于下沉气流将中高层的水平动量向近地面底层传递,从而激发此次雷暴大风。

关键词：雷暴大风数值模拟循环同化速度退模糊

Characteristic Verification and Parameter Optimization of Airbags Cushion System for Airborne Vehicle

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Chinese Journal of Mechanical Engineering 2014年第1期27卷 50-57页

作者： WANG Hongyan HONG Huangjie HAO Guixiang DENG Huaxia RUI Qiang li jianyang Department of Mechanical Engineering Academy of Armored Force Engineering School of Instrument Science and Opto-electronics Engineering Hefei University of Technology

Abstract： The major methods to investigate the airbags cushion system are experimental method, thermodynamic method and finite element method （FEM）. Airbags cushion systems are very complicated and very difficult to be investigated thoroughly by such methods For experimental method, it is nearly impossible to completely analyze and optimize the cushion characteristics of airbags of airborne vehicle because of charge issue, safety concern and time constraint. Thermodynamic method fails to take the non-linear effects of large airbag deformation and varied contact conditions into consideration. For finite element method, the FE model is usually complicated and the calculation takes tens of hours of CPU time. As a result, the optimization of the design based on a nonlinear model is very difficult by traditional iterative approach method. In this paper, a model based on FEM and control volume method is proposed to simulate landing cushion process of airborne vehicle with airbags cushion system in order to analyze and optimize the parameters in airbags cushion system. At first, the performance of airbags cushion system model is verified experimentally. In airdrop test, accelerometers are fixed in 4 test points distributed over engine mount, top, bottom and side armor plate of hull to obtain acceleration curves with time. The simulation results are obtained under the same conditions of the airdrop test and the simulation results agree very well with the experimental results, which indicate the established model is valid for further optimization. To optimize the parameters of airbags, equivalent response model based on Latin Hypercube DOE and radial basis function is employed instead of the complex finite element model. Then the optimal results based on equivalent response model are obtained using simulated annealing algorithm. After optimization, the maximal acceleration of airborne vehicle landing reduces 19.83%, while the energy absorption by airbags increases 7.85%. The

关键词： airborne vehicle airbag nonlinear finite element method verification equivalent response model

Active anticorrosion and self-healing coatings:A review with focus on multi-action smart coating strategies

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Journal of Materials Science & Technology 2022年第21期116卷 224-237页

作者： Inime Ime Udoh Hongwei Shi Enobong Felix Daniel jianyang li Songhua Gu Fuchun liu En-Hou Han CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Environmental and Chemical Engineering Shenyang Ligong UniversityShenyang 110159China University of Science and Technology of China Hefei 230026China

The development of smart coatings with potential for active anticorrosion and self-healing protection of metals is essential for long-term performance of metallic structures in aggressive chemical ***,emphasis has been placed on the development of advanced smart coatings for corrosion protection in different *** multifunctional coatings with fascinating stimuliresponsive functionalities are considered“smart”.The stimuli-responsive functionalities of these smart coatings when properly harnessed result in a class of coatings with inherent autonomous control of ***,when metals are exposed to aggressive environments,occurrences at the metalsolution interface cause environmental *** changes can be controlled when triggers from external environment set off active components of smart coating,thereby enhancing coating’s life and *** triggers include the availability of moisture,concentration of chloride ion,p H gradient,mechanical damage,impact,fatigue,light,redox activity and *** this review,recent technological trends in active anticorrosion and self-healing coatings as functional routes for metal protection are summarized,stimuli responsiveness and mechanisms of inhibition are discussed,and recent multi-action protective systems are particularly focused on.

关键词： Smart coating Active anticorrosion protection Self-healing Multi-action Protection mechanism

一例神经监测下耳后入路听神经瘤切除术围术期护理

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中国医学文摘（耳鼻咽喉科学） 2024年第3期39卷 201-203页

作者：柳笑榆郑兴媛李健洋杨秋花贺永超山东大学附属儿童医院山东济南250000 烟台毓璜顶医院山东烟台264000

目的总结神经监测下耳后入路听神经瘤切除术手术护理。方法报道一例神经监测下听神经瘤切除术患者的手术护理配合与治疗。结果通过耳后入路,显微解剖面神经三叉神经耳神经,准确定位,手术顺利切除听神经瘤,患者安返病房。结论充分运用了... 详细信息

目的总结神经监测下耳后入路听神经瘤切除术手术护理。方法报道一例神经监测下听神经瘤切除术患者的手术护理配合与治疗。结果通过耳后入路,显微解剖面神经三叉神经耳神经,准确定位,手术顺利切除听神经瘤,患者安返病房。结论充分运用了神经监测仪器,显微镜、耳钻等,将肿瘤切除彻底,手术切除是其主要治疗手段,因此神经监测可以更好地保护面神经和听神经的功能,提高肿瘤切除率,对保证手术顺利进行和提高手术效果具有积极的意义。

关键词：听神经瘤显微镜神经监测围术期护理耳后入路

The Effect of Notch Filter on RFI Suppression

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Wireless Sensor Network 2009年第3期1卷 196-205页

作者： Wenge CHANG jianyang li Xiangyang li 不详

Radio Frequency Interference (RFI) suppression is an important technique in the ultra-wideband synthetic aperture radar (UWB SAR). In this paper, we mainly analyze the performance of a notch filter for RFI sup-pression. The theoretical output from notch filter is presented based on RFI signal’s narrowband property. The research conclusion shows that the notch filter has significant effect on sidelobes of the system response, which might be considered to be false targets, however it has little effect on the resolution of the system re-sponse. The theoretical result is verified by simulation and experimental data processing both in one dimen-sion (range dimension) and in two dimensions (range and azimuth dimension).

关键词： RFI Supression Matched Filter Notch Filter SAR

Photoinduced generation of alkyl and phthalimide nitrogen radicals from N-hydroxyphthalimide esters for the synthesis of benzophenone-type bioisosteres

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Science China Chemistry 2024年第10期67卷 3389-3396页

作者： Fei li jianyang Dong Huijuan liao Jiayi Dang Xuechen Zhou Yuying Wang Chenya Wang Qin Jiang Gang li Dong Xue Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education and School of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi’an 710119China

N-Hydroxyphthalimide(NHPI)esters have emerged as powerful sources of alkyl radicals generated by single-electron transfer,but homolysis of NHPI ester to produce an alkyl radical and a phthalimide nitrogen radical is still in its *** this study,we developed a light-induced method for generation of alkyl and phthalimide nitrogen radicals from NHPI esters and subsequent reactions of the radicals with[1.1.1]propellane and aryl aldehydes for rapid generation of bicycle[1.1.1]pentane *** method does not require metals or photosensitizers,features a broad substrate scope(90 examples)and excellent functional group tolerance,and can be used for the functionalization of structurally complex natural products and *** investigations indicate that the reaction involves photoinduced homolytic cleavage of the Cs_(2)CO_(3)-NHPI ester complex to produce alkyl and phthalimide nitrogen radicals and subsequent hydrogen atom transfer between the phthalimide nitrogen radical and the aldehyde to generate an acyl radical.

关键词： phthalimide nitrogen radicals aryl aldehydes hydrogen atom transfer bicycle[1.1.1]pentane ketones bioisosteres

OKMC Simulation of the Evolution of Irradiation Defects in RPV Steel

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IMP & HIRFL Annual Report 2018年第1期 129-130页

作者： li jianyang Zhang Chonghong Ding Zhaonan 不详

Reactor Pressure Vessel(RPV)is a key structural component of nuclear *** has to endure high-dose neutron irradiation during *** irradiation produces defect clusters and solute segregation,causing hardening and embrittlement of the RPV steel.A pretty number of testing and characterization techniques of microstructure and mechanical properties utilizing miniaturized specimens have been developed[1−4].Current experimental studies show that the increase of nano-hardness and micro-hardness of materials is positively correlated with that of macroscopic yield stress and ductile-brittle transition temperature[5;6].Meanwhile,some physical models related to defects,solute cluster characteristics and hardness change of materials have been established[7;8],supposing that the hardness increment in irradiation material mainly comes from the large heterogeneous clusters.

关键词： microstructure ductile solute

5-3 Code Development for R&D of C-ADS Target Station

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IMP & HIRFL Annual Report 2015年第1期 224-225页

作者： Cai Hanjie Fu Fen li jianyang Yang Lei Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China University of Chinese Academy of Science Beijing 100049 China

For the R&D of the target station of C-ADS, especially for the conceptual design and feasibility verification of the initiative dense gravity-driven granular flow driven target, a special-purpose program which is accu... 详细信息

关键词： C-ADS Target Station

Channel estimation-based time-frequency neural network for post-equalization in underwater visible light communication

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Chinese Optics Letters 2024年第6期22卷 116-122页

作者： Haoyu Zhang li Yao Chaoxu Chen Yuan Wei Chao Shen jianyang Shi Junwen Zhang Ziwei li Nan Chi Key Laboratory for Information Science of Electromagnetic Waves(MoE) Department of Communication Science and EngineeringSchool of Information Science and TechnologyFudan UniversityShanghai 200433China Shanghai CIC of LEO Satellite Communication Technology Fudan UniversityShanghai 200433China Shanghai ERC of LEO Satellite Communication and Application Fudan UniversityShanghai 200433China

This Letter proposes a post-equalizer for underwater visible light communication(UVLC) systems that combines channel estimation and joint time-frequency analysis, named channel-estimation-based bandpass variable-order time-frequency network(CBV-TFNet). By utilizing a bandpass variable-order loss function with communication prior knowledge, CBVTFNet enhances communication performance and training stability. It enables lightweight implementation and faster convergence through a channel estimation-based mask. The superior performance of the proposed equalization method over Volterra and deep neural network(DNN)-based methods has been studied experimentally. Using bit-power loading discrete multitone (DMT) modulation, the proposed method achieves a transmission bitrate of 4.956 Gbps through a 1.2 m underwater channel utilizing only 38.15% of real multiplication calculations compared to the DNN equalizer and achieving a bitrate gain of440 Mbps and a significantly larger dynamic range over the LMS-Volterra equalizer. Results highlight CBV-TFNet's potential for future post-equalization in UVLC systems.

关键词： underwater visible light communication channel estimation post-equalizer neural network