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Shock Raman spectra and structural transformation of powdered TKX-50 by the plate impact experiments combined with real-time Raman detection

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Defence technology 2024年第1期

作者： Xue Yang qijun Liu Yundan Gan Lei Yang Zhengtang Liu Fusheng Liu

来源：博看期刊评论

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应用电轴垂线法判定心电轴2.0份评价

安徽医药 2024年第9期28卷 1833-1836页

作者：高启军别芳芳陈亚锋荆门市中心医院、荆楚理工学院附属荆门市中心医院心内科湖北荆门448000

目的寻找一种更简单、快速地确定心电轴的方法。方法电轴的垂线将6个肢体导联分为两组。电轴方向180°范围内的所有导联均为正向,而电轴方向相反的180°范围内的所有导联均为负向,电轴垂线相邻的两个导联QRS波群主波方向相反,以此帮助... 详细信息

目的寻找一种更简单、快速地确定心电轴的方法。方法电轴的垂线将6个肢体导联分为两组。电轴方向180°范围内的所有导联均为正向,而电轴方向相反的180°范围内的所有导联均为负向,电轴垂线相邻的两个导联QRS波群主波方向相反,以此帮助确定电轴垂线。六个肢体导联在−30°~12.°分布如下:aVL(−30°),Ⅰ(0°),−avR(30°),Ⅱ(60°),aVF(90°)和Ⅲ(12.°)。先检查外侧导联(aVL或Ⅲ)是否为负向或正负相等,如果超过一个导联是负的,按顺序逐一查看,直到发现一个正向或上下相等的导联。2.19年7月荆门中心医院的2.0份心电图纳入分析,从电轴垂线法、电脑法和查表法得到心电轴,用Pearson法分析相关系数和Bland-Altman分析差异性。结果3种方法判定心电轴的均数和标准差相似,电轴垂线法与查表法的相关系数为0.976。两种方法之间的平均偏差及其95%CI为0.88(−12.37,14.14)。结论电轴垂线法简单,方便,能较准确地确定QRS电轴。

关键词：心电描记术平均心电轴电轴垂线 QRS波群

A novel multiscale simulation framework for low-dimensional memristors

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Science China(Physics,Mechanics & Astronomy) 2023年第7期66卷 79-87页

作者： Shurong Pan Li Liu qijun Huang Jin He Hao Wang Sheng Chang Key Laboratory of Artificial Micro-and Nano-Structures of Ministry of Education School of Physics and TechnologyWuhan UniversityWuhan 430072China School of Microelectronics Wuhan UniversityWuhan 430072China

In recent years,the memristor has been widely considered an emerging device,but it has rarely been *** obstacle is the change in the intrinsic atomic level when it *** the density functional theory(DFT),this atomic level change in structure cannot be *** molecular dynamics(MD),memristor electronic transport properties cannot be *** this study,we propose a novel multiscale simulation framework merging MD,DFT,and the nonequilibrium Green’s function method,which can reveal not only a memristor’s basic working mechanism but also its transport *** verify our framework’s availability in guiding innovative memristor design,a new type of memristor,a planar monolayer MoS_(2.-based memristor,is simulated for the first *** popped S atoms’effect on its carrier transport is revealed,which clarifies the working mechanism of the planar monolayer MoS_(2.-based memory *** hope that this framework can shed light on the analysis and design of low-dimensional memristors.

关键词： multiscale framework memristor planar monolayer transport properties MoS_(2.

Simulation Study of Cloud Properties Affected by Heterogeneous Nucleation Using the GRAPES＿SCM during the TWP-ICE Campaign

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Journal of Meteorological Research 2019年第4期33卷 734-746页

作者： Zhe LI qijun LIU Zhanshan MA Jiong CHEN Qingu JIANG National Meteorological Center China Meteorological AdministrationBeijing 100081 Numerical Weather Prediction Center of China Meteorological Administration Beijing 100081 College of Global Change and Earth System Science Beijing Normal UniversityBeijing 100875

This study used the Global/Regional Assimilation and PrEdiction System Single-Column Model(GRAPES_SCM)to simulate monsoon precipitation with deep convective cloud and associated cirrus during the Tropical Warm Pool International Cloud Experiment(TWP-ICE),especially during the active and suppressed monsoon *** cases with different heterogeneous nucleation parameterizations were simulated by using the ensemble *** simulations clearly separated the active and suppressed monsoon periods,and they reproduced the major characteristics of monsoonal cloud such as the total cloud hydrometeor mixing ratio distribution,and precipitation and radiation *** results showed that the number concentration production rate of different heterogeneous nucleation parameterizations varied substantially under the given temperature and water vapor mixing ***,ice formation and precipitation during the monsoon period were affected only slightly by the different heterogeneous nucleation *** study also captured clear competition between different ice formation processes.

关键词： Liuma microphysics scheme monsoon precipitation cloud microphysics heterogeneous nucleation GRAPES_SCM

Quantized robust H-two filtering for Markovian jump linear systems over networks with nonaccessible mode information

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控制理论与应用（英文版） 2011年第4期9卷 505-512页

作者： Tao LIU qijun CHEN Hao ZHANG Iko MIYAZAWA Department of Electronics and Information Engineering Tongji University Shanghai 201804 China Key Laboratory of Embedded System and Service Computing Tongji University Ministry of Education Shanghai 201804 China Department of Machine Control Technology Kanagawa Industrial Technology Center Kanagawa 243-0435 Japan

This paper is concerned with the problems of H-two filtering for discrete-time Markovian jump linear systems subject to logarithmic quantization. We assume that only the output of the system is available, and therefore the mode information is nonaccessible. In this paper, a mode-independent quantized H-two filter is designed such that filter error system is stochastically stable. To this end, sufficient conditions for the existence of an upper bound of H-two norm are presented in terms of linear matrix inequalities. Considering uncertainty of system matrices, a robust H-two filter is designed. The proposed method is also applicable to cover the case where the transition probability matrix is not exactly known but belongs to a given polytope. Finally, numerical examples are provided to demonstrate the effectiveness of the proposed approach.

关键词： Markovian jump linear systems Quantized robust H-two filter Mode independent Sector bound approach Linear matrix inequalities

Machine learning method for tight-binding Hamiltonian parameterization from ab-initio band structure

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npj Computational Materials 2021年第1期7卷 79-88页

作者： Zifeng Wang Shizhuo Ye Hao Wang Jin He qijun Huang Sheng Chang Key Laboratory of Artificial Micro-and Nano-Structures of Ministry of Education and School of Physics and Technology Wuhan University430072 WuhanHubeiPeople’s Republic of China

The tight-binding(TB)method is an ideal candidate for determining electronic and transport properties for a large-scale *** describes the system as real-space Hamiltonian matrices expressed on a manageable number of parameters,leading to substantially lower computational costs than the ab-initio *** the whole system is defined by the parameterization scheme,the choice of the TB parameters decides the reliability of the TB *** typical empirical TB method uses the TB parameters directly from the existing parameter sets,which hardly reproduces the desired electronic structures quantitatively without specific *** is thus not suitable for quantitative studies like the transport property *** ab-initio TB method derives the TB parameters from the ab-initio results through the transformation of basis functions,which achieves much higher numerical ***,it assumes prior knowledge of the basis and may encompass truncation ***,a machine learning method for TB Hamiltonian parameterization is proposed,within which a neural network(NN)is introduced with its neurons acting as the TB matrix *** method can construct the empirical TB model that reproduces the given ab-initio energy bands with predefined accuracy,which provides a fast and convenient way for TB model construction and gives insights into machine learning applications in physical problems.

关键词： Hamiltonian system assume

Robust Navier-Stokes method for predicting unsteady flowfield and aerodynamic characteristics of helicopter rotor

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Chinese Journal of Aeronautics 2018年第2期31卷 214-224页

作者： qijun ZHAO Guoqing ZHAO Bo WANG Qing WANG Yongjie SHI Guohua XU National Key Laboratory of Rotorcraft Aeromechanics Nanjing University of Aeronautics and Astronautics

A robust unsteady rotor flowfield solver CLORNS code is established to predict the complex unsteady aerodynamic characteristics of rotor flowfield. In order to handle the difficult problem about grid generation around rotor with complex aerodynamic shape in this CFD code,a parameterized grid generated method is established, and the moving-embedded grids are constructed by several proposed universal methods. In this work, the unsteady Reynolds-Averaged Navier-Stokes（RANS） equations with Spalart-Allmaras are selected as the governing equations to predict the unsteady flowfield of helicopter rotor. The discretization of convective fluxes is accomplished by employing the second-order central difference scheme, third-order MUSCL-Roe scheme, and fifth-order WENO-Roe scheme. Aimed at simulating the unsteady aerodynamic characteristics of helicopter rotor, the dual-time scheme with implicit LU-SGS scheme is employed to accomplish the temporal discretization. In order to improve the computational efficiency of holecells and donor elements searching of the moving-embedded grid technology, the ‘‘disturbance diffraction method＂ and ‘‘minimum distance scheme of donor elements method＂ are established in this work. To improve the computational efficiency, Message Passing Interface（MPI） parallel method based on subdivision of grid, local preconditioning method and Full Approximation Storage（FAS） multi-grid method are combined in this code. By comparison of the numerical results simulated by CLORNS code with test data, it is illustrated that the present code could simulate the aerodynamic loads and aerodynamic noise characteristics of helicopter rotor accurately.

关键词： Aerodynamic characteristicsHelicopter rotor Moving-embedded grid Navier-Stokes equations Upwind schemes

Precise methods for conducted EMI modeling,analysis,and prediction

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Science China(Technological Sciences) 2008年第6期51卷 641-655页

作者： MA WeiMing ZHAO ZhiHua MENG Jin PAN qijun ZHANG Lei National Key Laboratory for Ship Integrated Power System Technology Naval University of EngineeringWuhan 430033China

Focusing on the state-of-the-art conducted EMI prediction, this paper presents a noise source lumped circuit modeling and identification method, an EMI modeling method based on multiple slope approximation of switching transitions, and dou-ble Fourier integral method modeling PWM conversion units to achieve an accurate modeling of EMI noise source. Meanwhile, a new sensitivity analysis method, a general coupling model for steel ground loops, and a partial element equivalent circuit method are proposed to identify and characterize conducted EMI coupling paths. The EMI noise and propagation modeling provide an accurate prediction of conducted EMI in the entire frequency range (0―10 MHz) with good practicability and generality. Finally a new measurement approach is presented to identify the surface current of large dimensional metal shell. The proposed analytical modeling methodology is verified by experimental results.

关键词： EMC conducted EMI modeling and prediction sensitivity ground impedance

Multidiscipline Applications of Triboelectric Nanogenerators for the Intelligent Era of Internet of Things

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Nano-Micro Letters 2023年第1期15卷 252-292页

作者： Xiaole Cao Yao Xiong Jia Sun Xiaoyin Xie qijun Sun Zhong Lin Wang Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400People’s Republic of China School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049People’s Republic of China School of Physics and Electronics Central South UniversityChangsha 410083People’s Republic of China School of Chemistry and Chemical Engineering Hubei Polytechnic UniversityHuangshi 435003People’s Republic of China Shandong Zhongke Naneng Energy Technology Co. Ltd.Dongying 7061People’s Republic of China School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

In the era of 5G and the Internet of things(IoTs),vari-ous human-computer interaction systems based on the integration of triboelectric nanogenerators(TENGs)and IoTs technologies dem-onstrate the feasibility of sustainable and self-powered functional *** rapid development of intelligent applications of IoTs based on TENGs mainly relies on supplying the harvested mechanical energy from surroundings and implementing active sensing,which have greatly changed the way of human production and daily *** review mainly introduced the TENG applications in multidisci-pline scenarios of IoTs,including smart agriculture,smart industry,smart city,emergency monitoring,and machine learning-assisted artificial intelligence *** challenges and future research directions of TENG toward IoTs have also been *** exten-sive developments and applications of TENG will push forward the IoTs into an energy autonomy fashion.

关键词： Triboelectric nanogenerator Self-powered sensor Internet of things Artificial intelligence Machine learning